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Numerical simulations of heavily polluted fine-grained sediment remobilization using 1D, 1D+, and 2D channel schematization.
Kaiglová, Jana; Langhammer, Jakub; Jiřinec, Petr; Janský, Bohumír; Chalupová, Dagmar
This article used various hydrodynamic and sediment transport models to analyze the potential and the limits of different channel schematizations. The main aim was to select and evaluate the most suitable simulation method for fine-grained sediment remobilization assessment. Three types of channel schematization were selected to study the flow potential for remobilizing fine-grained sediment in artificially modified channels. Schematization with a 1D cross-sectional horizontal plan, a 1D+ approach, splitting the riverbed into different functional zones, and full 2D mesh, adopted in MIKE by the DHI modeling suite, was applied to the study. For the case study, a 55-km stretch of the Bílina River, in the Czech Republic, Central Europe, which has been heavily polluted by the chemical and coal mining industry since the mid-twentieth century, was selected. Long-term exposure to direct emissions of toxic pollutants including heavy metals and persistent organic pollutants (POPs) resulted in deposits of pollutants in fine-grained sediments in the riverbed. Simulations, based on three hydrodynamic model schematizations, proved that for events not exceeding the extent of the riverbed profile, the 1D schematization can provide comparable results to a 2D model. The 1D+ schematization can improve accuracy while keeping the benefits of high-speed simulation and low requirements of input DEM data, but the method's suitability is limited by the channel properties. PMID:25687259
Simulation of Organic Solar Cells Using AMPS-1D Program
Directory of Open Access Journals (Sweden)
Samah G. Babiker
Full Text Available The analysis of microelectronic and photonic structure in one dimension program [AMPS-1D] program has been successfully used to study inorganic solar cells. In this work the program has been used to optimize the performance of the organic solar cells. The cells considered consist of poly(2-methoxy-5-(3,7- dimethyloctyloxy-1,4-phenylenevinylene [MDMO-PPV
1D engine simulation of a turbocharged SI engine with CFD computation on components
Renberg, Ulrica
Techniques that can increase the SI- engine efficiency while keeping the emissions very low is to reduce the engine displacement volume combined with a charging system. Advanced systems are needed for an effective boosting of the engine and today 1D engine simulation tools are often used for their optimization. This thesis concerns 1D engine simulation of a turbocharged SI engine and the introduction of CFD computations on components as a way to assess inaccuracies in the 1D model. 1D engine ...
Linking 1D Stellar Evolution to 3D Hydrodynamical Simulations
Cristini, Andrea; Georgy, Cyril; Meakin, Casey; Arnett, David; Viallet, Maxime
In this contribution we present initial results of a study on convective boundary mixing (CBM) in massive stellar models using the GENEVA stellar evolution code. Before undertaking costly 3D hydrodynamic simulations, it is important to study the general properties of convective boundaries, such as the: composition jump; pressure gradient; and `stiffness'. Models for a 15Mo star were computed. We found that for convective shells above the core, the lower (in radius or mass) boundaries are `stiffer' according to the bulk Richardson number than the relative upper (Schwarzschild) boundaries. Thus, we expect reduced CBM at the lower boundaries in comparison to the upper. This has implications on flame front propagation and the onset of novae.
Modeling blood flow circulation in intracranial arterial networks: a comparative 3D/1D simulation study.
Grinberg, L; Cheever, E; Anor, T; Madsen, J R; Karniadakis, G E
We compare results from numerical simulations of pulsatile blood flow in two patient-specific intracranial arterial networks using one-dimensional (1D) and three-dimensional (3D) models. Specifically, we focus on the pressure and flowrate distribution at different segments of the network computed by the two models. Results obtained with 1D and 3D models with rigid walls show good agreement in massflow distribution at tens of arterial junctions and also in pressure drop along the arteries. The 3D simulations with the rigid walls predict higher amplitude of the flowrate and pressure temporal oscillations than the 1D simulations with compliant walls at various segments even for small time-variations in the arterial cross-sectional areas. Sensitivity of the flow and pressure with respect to variation in the elasticity parameters is investigated with the 1D model. PMID:20661645
Simulation of Tunnel Junction in Cascade Solar Cell (GaAs/Ge) Using AMPS-1D
Benmoussa Dennai; H. Ben Slimane; Helmaoui, A.
The development of the tunnel junction interconnect was key the first two-terminal monolithic, multi-junction solar cell development. This paper describes simulation for the tunnel junction (GaAs) between top cell (GaAs) and bottom cell (Ge). This solar cell cascade was simulated when using one dimensional simulation program called analysis of microelectronic and photonic structures (AMPS-1D). In the simulation, the thickness of the tunnel junction layer was varied from 10 to 50 nm. By varyin...
Institute of Scientific and Technical Information of China (English)
ZHANG Xiao-xi; CHENG Yong-guang
Although the hydraulic transients in pipe systems are usually simulated by using a one-dimensional (l-D) approach,local three-dimensional (3-D) simulations are necessary because of obvious 3-D flow features in some local regions of the hydropower systems.This paper combines the 1-D method with a 3-D fluid flow model to simulate the Multi-Dimensional (MD) hydraulic transients in hydropower systems and proposes two methods for modeling the compressible watcr with the correct wave speed,and two strategies for efficiently coupling the 1-D and 3-D computational domains.The methods are validated by simulating the water hammer waves and the oscillations of the water level in a surge tank,and comparing the results with the 1 -D solution data.An MD study is conducted for the transient flows in a realistic water conveying system that consists of a draft tube,a tailrace surge tank and a tailrace tunnel.It is shown that the 1-D-3-D coupling approach is an efficient and promising way to simulate the hydraulic transients in the hydropower systems in which the interactions between 1-D hydraulic fluctuations of the pipeline systems and the local 3-D flow patterns should be considered.
Simulation of Tunnel Junction in Cascade Solar Cell (GaAs/Ge Using AMPS-1D
Directory of Open Access Journals (Sweden)
Benmoussa Dennai
Full Text Available The development of the tunnel junction interconnect was key the first two-terminal monolithic, multi-junction solar cell development. This paper describes simulation for the tunnel junction (GaAs between top cell (GaAs and bottom cell (Ge. This solar cell cascade was simulated when using one dimensional simulation program called analysis of microelectronic and photonic structures (AMPS-1D. In the simulation, the thickness of the tunnel junction layer was varied from 10 to 50 nm. By varying thickness of tunnel junction layer the simulated device performance was demonstrate in the form of current-voltage(I-V characteristics and quantum efficiency (QE.
Build up An Operational Flood Simulation from Existing 1D Channel Flow Works
Chang, Che-Hao; Hsu, Chih-Tsung; Wu, Shiang-Jen; Lien, Ho-Cheng; Shen, Jhih-Cyuan; Chung, Ming-Ko
Several 2D flood simulations will be developed for urban area in recent years in Taiwan. Original ideas focus on the static flood maps produced by the 2D flood simulation with respect to design events, which could be useful no matter for planning or disaster awareness. However, an extra bonus is expected to see if we can reuse the 2D flood simulation framework for operational use or not. Such a project goal inspire us to setup a standard operation procedure before any progress from existing 1D channel flow works. 3 key issues are taken into account in the SOP: 1. High Resolution Terrain: A 1m resolution digital terrain model (DTM) is considered as a reference. The Channels and structures should be setup in 1D channel flow works if we can identify under such high resolution. One should examine the existing 1D channel flow works consistent with the DTM or not. 2. Meteo Stations Referenced: Real time precipitation would be send to referenced location in RR models during an operational forecast. Existing 1D channels flow works are usually specifically for design events which are not necessarily equipped with such references. 3. Time Consuming: A full scale 2D flood simulation needs a lot of computation resources. A solution should be derived within practical time limits. Under the above consideration, some impacts and procedures will be analyzed and developed to setup the SOP for further model modification.
Numerical simulation of Ge solar cells using D-AMPS-1D code
Energy Technology Data Exchange (ETDEWEB)
Barrera, Marcela, E-mail: firstname.lastname@example.com [Comision Nacional de Energia Atomica, Avenida General Paz 1499, San Martin 1650, Buenos Aires (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) (Argentina); Rubinelli, Francisco [Instituto de Desarrollo Tecnologico para la Industria Quimica (INTEC)-CONICET, Gueemes 3450, Santa Fe 3000 (Argentina); Rey-Stolle, Ignacio [Instituto de Energia Solar, Universidad Politecnica de Madrid, Avenida Complutense 30, Madrid 28040 (Spain); Pla, Juan [Comision Nacional de Energia Atomica, Avenida General Paz 1499, San Martin 1650, Buenos Aires (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) (Argentina)
A solar cell is a solid state device that converts the energy of sunlight directly into electricity by the photovoltaic effect. When light with photon energies greater than the band gap is absorbed by a semiconductor material, free electrons and free holes are generated by optical excitation in the material. The main characteristic of a photovoltaic device is the presence of internal electric field able to separate the free electrons and holes so they can pass out of the material to the external circuit before they recombine. Numerical simulation of photovoltaic devices plays a crucial role in their design, performance prediction, and comprehension of the fundamental phenomena ruling their operation. The electrical transport and the optical behavior of the solar cells discussed in this work were studied with the simulation code D-AMPS-1D. This software is an updated version of the one-dimensional (1D) simulation program Analysis of Microelectronic and Photonic Devices (AMPS) that was initially developed at The Penn State University, USA. Structures such as homojunctions, heterojunctions, multijunctions, etc., resulting from stacking layers of different materials can be studied by appropriately selecting characteristic parameters. In this work, examples of cells simulation made with D-AMPS-1D are shown. Particularly, results of Ge photovoltaic devices are presented. The role of the InGaP buffer on the device was studied. Moreover, a comparison of the simulated electrical parameters with experimental results was performed.
INFIL1D: a quasi-analytical model for simulating one-dimensional, constant flux infiltration
International Nuclear Information System (INIS)
The program INFIL1D is designed to calculate approximate wetting-front advance into an unsaturated, uniformly moist, homogeneous soil profile, under constant surface-flux conditions. The code is based on a quasi-analytical method, which utilizes an assumed invariant functional relationship between reduced (normalized) flux and water content. The code uses general hydraulic property data in tabular form to simulate constant surface-flux infiltration. 10 references, 4 figures
Simulation of CIGS Thin Film Solar Cells Using AMPS-1D
Directory of Open Access Journals (Sweden)
J.R. Ray
Full Text Available The solar cell structure based on copper indium gallium diselenide (CIGS as the absorber layer, cadmium sulfide (CdS as a buffer layer un-doped (i and Aluminium (Al doped zinc oxide (ZnO as a window layer was simulated using the one dimensional simulation program called analysis of microelectronic and photonic structures (AMPS-1D. In the simulation, the thickness of CIGS layer was varied from 300 to 3000 nm. The rest of layer's thicknesses were kept constant, viz. 60 nm for CdS, and 80 nm and 500 nm for i- and Al-ZnO, respectively. By varying thickness of CIGS layer the simulated device performance was demonstrate in the form of current-voltage (I-V characteristics and quantum efficiency (QE.
Reciprocating Compressor 1D Thermofluid Dynamic Simulation: Problems and Comparison with Experimental Data
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A. Gimelli
Full Text Available The authors here extend a 0D-1D thermofluid dynamic simulation approach to describe the phenomena internal to the volumetric machines, reproducing pressure waves' propagation in the ducts. This paper reports the first analysis of these phenomena in a reciprocating compressor. The first part presents a detailed experimental analysis of an open-type reciprocating compressor equipped with internal sensors. The second part describes a 0D-1D thermofluid dynamic simulation of the compressor. Comparison of computed and measured values of discharge mass flow rate shows a good agreement between results for compression ratio <5. Then, to improve the model fitting at higher pressures, a new scheme has been developed to predict the blow-by through the ring pack volumes. This model is based on a series of volumes and links which simulate the rings' motions inside the grooves, while the ring dynamics are imposed using data from the literature about blow-by in internal combustion engines. The validation is obtained comparing experimental and computing data of the two cylinder engine blowby. After the validation, a new comparison of mass flow rate on the compressor shows a better fitting of the curves at higher compression ratio.
Simulation of hetero-junction silicon solar cells with AMPS-1D
Energy Technology Data Exchange (ETDEWEB)
Hernandez-Como, Norberto; Morales-Acevedo, Arturo [Centro de Investigacion y de Estudios Avanzados del IPN, Electrical Engineering Department, Avenida IPN No. 2508, 07360 Mexico, D. F. (Mexico)
Mono- and poly-crystalline silicon solar cell modules currently represent between 80% and 90% of the PV world market. The reasons are the stability, robustness and reliability of this kind of solar cells as compared to those of emerging technologies. Then, in the mid-term, silicon solar cells will continue playing an important role for their massive terrestrial application. One important approach is the development of silicon solar cells processed at low temperatures (less than 300 C) by depositing amorphous silicon layers with the purpose of passivating the silicon surface, and avoiding the degradation suffered by silicon when processed at temperatures above 800 C. This kind of solar cells is known as HIT cells (hetero-junction with an intrinsic thin amorphous layer) and are already produced commercially (Sanyo Ltd.), reaching efficiencies above 20%. In this work, HIT solar cells are simulated by means of AMPS-1D, which is a program developed at Pennsylvania State University. We shall discuss the modifications required by AMPS-1D for simulating this kind of structures since this program explicitly does not take into account interfaces with high interfacial density of states as occurs at amorphous-crystalline silicon hetero-junctions. (author)
Computing 1-D atomic densities in macromolecular simulations: the Density Profile Tool for VMD
Giorgino, Toni
Molecular dynamics simulations have a prominent role in biophysics and drug discovery due to the atomistic information they provide on the structure, energetics and dynamics of biomolecules. Specialized software packages are required to analyze simulated trajectories, either interactively or via scripts, to derive quantities of interest and provide insight for further experiments. This paper presents the Density Profile Tool, a package that enhances the Visual Molecular Dynamics environment with the ability to interactively compute and visualize 1-D projections of various density functions of molecular models. We describe how the plugin is used to perform computations both via a graphical interface and programmatically. Results are presented for realistic examples, all-atom bilayer models, showing how mass and electron densities readily provide measurements such as membrane thickness, location of structural elements, and how they compare to X-ray diffraction experiments.
Transient 1D transport equation simulated by a mixed Green element formulation
Taigbenu, Akpofure Efemena; Onyejekwe, Okey Oseloka
New discrete element equations or coefficients are derived for the transient 1D diffusion-advection or transport equation based on the Green element replication of the differential equation using linear elements. The Green element method (GEM), which solves the singular boundary integral theory (a Fredholm integral equation of the second kind) on a typical element, gives rise to a banded global coefficient matrix which is amenable to efficient matrix solvers. It is herein derived for the transient 1D transport equation with uniform and non-uniform ambient flow conditions and in which first-order decay of the containment is allowed to take place. Because the GEM implements the singular boundary integral theory within each element at a time, the integrations are carried out in exact fashion, thereby making the application of the boundary integral theory more utilitarian. This system of discrete equations, presented herein for the first time, using linear interpolating functions in the spatial dimensions shows promising stable characteristics for advection-dominant transport. Three numerical examples are used to demonstrate the capabilities of the method. The second-order-correct Crank-Nicolson scheme and the modified fully implicit scheme with a difference weighting value of two give superior solutions in all simulated examples.
Computer Simulation Study of Thermal Conduction in 1D Chains of Anharmonic Oscillators
Institute of Scientific and Technical Information of China (English)
Tejal N.Shah; P.N.Gajjar
In this work thermal conduction in one-dimensional (1D) chains of anharmonic oscillators are studied using computer simulation.The temperature profile,heat flux and thermal conductivity are investigated for chain length N =100,200,400,800 and 1600.In the computer simulation anharmonicity is introduced due to Fermi-Pasta-Ulam-β (FPU-β) model For substrate interaction,an onsite potential due to Frenkel-Kontorova (FK) model has been used.Numerical simulations demonstrate that temperature gradient scales behave as N-1 linearly with the relation J =0.1765/N.For the thermal conductivity K,KN to N obey the linear relation of the type KN =0.8805N.It is shown that thermal transport is dependent on phonon-phonon interaction as well as phonon-lattice interaction.The thermal conductivity increaseslinearly with increase inanharmonicity and predicts relation κ =0.133 + 0.804β.It is also concluded that for higher value of the strength of the onsite potential system tends to a thermal insulator.
Specifications of ZnO growth for heterostructure solar cell and PC1D based simulations
Directory of Open Access Journals (Sweden)
Babar Hussain
Full Text Available This data article is related to our recently published article (Hussain et al., in press [1] where we have proposed a new solar cell model based on n-ZnO as front layer and p-Si as rear region. The ZnO layer will act as an active n-layer as well as antireflection (AR coating saving considerable processing cost. There are several reports presenting use of ZnO as window/antireflection coating in solar cells (Mansoor et al., 2015; Haq et al., 2014; Hussain et al., 2014; Matsui et al., 2014; Ding et al., 2014 [2–6] but, here, we provide data specifically related to simultaneous use of ZnO as n-layer and AR coating. Apart from the information we already published, we provide additional data related to growth of ZnO (with and without Ga incorporation layers using MOCVD. The data related to PC1D based simulation of internal and external quantum efficiencies with and without antireflection effects of ZnO as well as the effects of doping level in p-Si on current–voltage characteristics have been provided.
The FLO Diffusive 1D-2D Model for Simulation of River Flooding
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Costanza Aricò
Full Text Available An integrated 1D-2D model for the solution of the diffusive approximation of the shallow water equations, named FLO, is proposed in the present paper. Governing equations are solved using the MArching in Space and Time (MAST approach. The 2D floodplain domain is discretized using a triangular mesh, and standard river sections are used for modeling 1D flow inside the section width occurring with low or standard discharges. 1D elements, inside the 1D domain, are quadrilaterals bounded by the trace of two consecutive sections and by the sides connecting their extreme points. The water level is assumed to vary linearly inside each quadrilateral along the flow direction, but to remain constant along the direction normal to the flow. The computational cell can share zero, one or two nodes with triangles of the 2D domain when lateral coupling occurs and more than two nodes in the case of frontal coupling, if the corresponding section is at one end of the 1D channel. No boundary condition at the transition between the 1D-2D domain has to be solved, and no additional variable has to be introduced. Discontinuities arising between 1D and 2D domains at 1D sections with a top width smaller than the trace of the section are properly solved without any special restriction on the time step.
Simulation of the load rejection transient process of a francis turbine by using a 1-D-3-D coupling approach
Institute of Scientific and Technical Information of China (English)
张晓曦; 程永光; 杨建东; 夏林生; 赖旭
This paper presents the simulation and the analysis of the transient process of a Francis turbine during the load rejection by employing a one-dimensional and three-dimensional (1-D-3-D) coupling approach. The coupling is realized by partly overlapping the 1-D and 3-D parts, the water hammer wave is modeled by defining the pressure dependent density, and the guide vane closure is treated by a dynamic mesh method. To verify the results of the coupling approach, the transient parameters for both typical models and a real power station are compared with the data obtained by the 1-D approach, and good agreements are found. To investigate the differences between the transient and steady states at the corresponding operating parameters, the flow characteristics inside a turbine of the real power station are simulated by both transient and steady methods, and the results are analyzed in details. Our analysis suggests that there are just a little differences in the turbine outer characteristics, thus the traditional 1-D method is in general acceptable. However, the flow patterns in the spiral casing, the draft tube, and the runner passages are quite different: the transient situation has obvious water hammer waves, the water inertia, and some other effects. These may be crucial for the draft tube pul- sation and need further studies.
NASA One-Dimensional Combustor Simulation--User Manual for S1D_ML
Stueber, Thomas J.; Paxson, Daniel E.
The work presented in this paper is to promote research leading to a closed-loop control system to actively suppress thermo-acoustic instabilities. To serve as a model for such a closed-loop control system, a one-dimensional combustor simulation composed using MATLAB software tools has been written. This MATLAB based process is similar to a precursor one-dimensional combustor simulation that was formatted as FORTRAN 77 source code. The previous simulation process requires modification to the FORTRAN 77 source code, compiling, and linking when creating a new combustor simulation executable file. The MATLAB based simulation does not require making changes to the source code, recompiling, or linking. Furthermore, the MATLAB based simulation can be run from script files within the MATLAB environment or with a compiled copy of the executable file running in the Command Prompt window without requiring a licensed copy of MATLAB. This report presents a general simulation overview. Details regarding how to setup and initiate a simulation are also presented. Finally, the post-processing section describes the two types of files created while running the simulation and it also includes simulation results for a default simulation included with the source code.
A PIC simulation study on the evolution of the real and imaginary frequencies of 1D plasma waves
Grismayer, Thomas; Fahlen, Jay; Winjum, Benjamin; Tsung, Frank; Morales, George; Mori, Warren
We use electrostatic PIC simulations to study the evolution of both the real and complex frequency of 1D plasma waves. We are considering especially the linear regime where the asymptotic damping rate is much bigger than the bounce frequency. In this regime the waves are typically very small and below the thermal noise. These waves can be studied using a subtraction technique where two simulations where identical random number generation seeds are carried out. In the first, a small amplitude wave is excited. In the second simulation no wave is excited. The results from each simulation are subtracted providing a clean linear wave that can be studied. As previously predicted, the damping is divided in two stages, an initial transient and an asymptotic decay (Landau's formula). The time-dependent resonant width measured in the simulations is compared with the theoretical prediction. In typical ICF plasmas nld^3 damping.
Understanding the Rayleigh-Taylor instability through 1D and 3D simulations
Mikhaeil, Mark; Denissen, Nicholas; Ranjan, Devesh
A series of Rayleigh-Taylor instability numerical simulations were completed using the Arbitrary Lagrangian-Eulerian hydrocode FLAG developed at Los Alamos National Laboratory. One-dimensional simulations employed a Reynolds-averaged Navier-Stokes approach with turbulence closure models selected from the Besnard-Harlow-Rauenzahn family of models. Growth rate parameters and turbulence statistics are derived from these simulations and compared between closure models. Variations from experimental results are explored and used to validate the models. The effect of density ratio on the bubble-spike growth rate asymmetry is also investigated. High resolution three-dimensional large eddy simulations (LES) are also completed and presented. LES were initialized using a multi-modal perturbation prescribed from experimental data collected at the Georgia Institute of Technology multi-layer Gas Tunnel facility. Turbulence statistics are gathered by averaging many simulations started with different initial conditions. Late time development is compared to Gas Tunnel experimental results and previous LES.
1D Monte-Carlo simulation of charge accumulation process inside Teflon film
Watanabe, Rikio; Ota, Masahiro; Tanaka, Yasuhiro; Tomita, Nobuyuki; 渡辺 力夫; 大田 真広; 田中 康寛; 冨田 信之
The charge accumulation processes inside a Teflon film are investigated with one-dimensional Monte-Carlo simulation. Elastic and inelastic scattering processes are considered in the collisions between electrons and atoms consisting of Teflon (CF4). Electron-phonon interaction and trapping effect are also included in the estimation of total cross section. A case of 20 keV electron irradiation is tested and charge accumulation process is successfully simulated. The electric field is also calcul...
Numerical Simulation of 1-D and 2-D Continuous Geo-electrical Magnetotelluric Forward
Directory of Open Access Journals (Sweden)
Cao Chuang Hua
Full Text Available Finite element technology in one-dimensional layered media of the continuous electro-media and the two-dimensional continuous electrical is displayed in ways of the special matrix equations in the variation formula and split technical conditions. To achieve a one-dimensional layered continuous electrical finite element numerical simulation of the media, the introduction of the secondary triangulation rectangular subdivision has been used to the two-dimensional numerical simulation, and using the rectangular center to set up the virtual point method to reduce the computational workload in calculation. Then design a meaningful manner electric model, the base power model analysis of electromagnetic waves in the rock, they all provide the guidance for the actual production.
Analog Quantum Simulation of (1+1)D Lattice QED with Trapped Ions
Yang, Dayou; Johanning, Michael; Wunderlich, Christof; Zoller, Peter; Hauke, Philipp
The prospect of quantum simulating lattice gauge theories opens exciting possibilities for understanding fundamental forms of matter. Here, we show that trapped ions represent a promising platform in this context when simultaneously exploiting internal pseudo-spins and external phonon vibrations. We illustrate our ideas with two complementary proposals for simulating lattice-regularized quantum electrodynamics (QED) in (1+1) space-time dimensions. The first scheme replaces the gauge fields by local vibrations with a high occupation number. By numerical finite-size scaling, we demonstrate that this model recovers Wilson's lattice gauge theory in a controlled way. Its implementation can be scaled up to tens of ions in an array of micro-traps. The second scheme represents the gauge fields by spins 1/2, and thus simulates a quantum link model. As we show, this allows the fermionic matter to be replaced by bosonic degrees of freedom, permitting small-scale implementations in a linear Paul trap. Both schemes work o...
Colliding Two Shocks: 1-D full Particle-in-Cell Simulation
Nakanotani, Masaru; Hada, T.; Matsukiyo, Shuichi; Mazelle, Christian
Shock-shock interactions occur on various places in space and the interaction can produce high energy particles. A coronal mass ejection driven shock can collide with the Earth's bow shock [Hietala et al., 2011]. This study reported that ions are accelerated by the first Fermi acceleration between the two shocks before the collision. An electron acceleration through an interplanetary shock-Earth's bow shock interaction was also reported [Terasawa et al., 1997]. Shock-shock interactions can occur in astrophysical phenomena as well as in the heliosphere. For example, a young supernova shock can collide with the wind termination shock of a massive star if they are close to each other [Bykov et al., 2013]. Although hybrid simulations (ions and electrons treated as super-particles and mass-less fluid, respectively) were carried out to understand the kinetic nature of a shock-shock interaction [Cargill et al., 1986], hybrid simulations cannot resolve electron dynamics and non-thermal electrons. We, therefore, use one-dimensional full particle-in-cell (PIC) simulations to investigate a shock-shock interaction in which two shocks collide head-on. In a case of quasi-perpendicular shocks, electrons are accelerated by the mirror reflection between the two shocks before the collision (Fermi acceleration). On the other hand, because ions cannot go back upstream, the electron acceleration mechanism does not occur for ions. In a case of quasi-parallel shocks, ions can go back upstream and are accelerated at the shocks. The accelerated ions have great effect on the shock structure.
Quantum simulation of the cooperative Jahn-Teller transition in 1D ion crystals.
Porras, Diego; Ivanov, Peter A; Schmidt-Kaler, Ferdinand
The Jahn-Teller effect explains distortions and nondegenerate energy levels in molecular and solid-state physics via a coupling of effective spins to collective bosons. Here we propose and theoretically analyze the quantum simulation of a many-body Jahn-Teller model with linear ion crystals subjected to magnetic field gradients. We show that the system undergoes a quantum magnetic structural phase transition which leads to a reordering of particle positions and the formation of a spin-phonon quasicondensate in mesoscopic ion chains. PMID:23003971
Simulating the focusing of light onto 1D nanostructures with a B-spline modal method
Bouchon, P.; Chevalier, P.; Héron, S.; Pardo, F.; Pelouard, J.-L.; Haïdar, R.
Focusing the light onto nanostructures thanks to spherical lenses is a first step to enhance the field, and is widely used in applications, in particular for enhancing non-linear effects like the second harmonic generation. Nonetheless, the electromagnetic response of such nanostructures, which have subwavelength patterns, to a focused beam can not be described by the simple ray tracing formalism. Here, we present a method to compute the response to a focused beam, based on the B-spline modal method. The simulation of a gaussian focused beam is obtained thanks to a truncated decomposition on plane waves computed on a single period, which limits the computation burden.
A well-balanced finite volume scheme for 1D hemodynamic simulations
Delestre, Olivier
We are interested in simulating blood flow in arteries with variable elasticity with a one dimensional model. We present a well-balanced finite volume scheme based on the recent developments in shallow water equations context. We thus get a mass conservative scheme which also preserves equilibria of Q=0. This numerical method is tested on analytical tests. Nous nous int\\'eressons \\`a la simulation d'\\'ecoulements sanguins dans des art\\`eres dont les parois sont \\`a \\'elasticit\\'e variable. Ceci est mod\\'elis\\'e \\`a l'aide d'un mod\\`ele unidimensionnel. Nous pr\\'esentons un sch\\'ema "volume fini \\'equilibr\\'e" bas\\'e sur les d\\'eveloppements r\\'ecents effectu\\'es pour la r\\'esolution du syst\\`eme de Saint-Venant. Ainsi, nous obtenons un sch\\'ema qui pr\\'eserve le volume de fluide ainsi que les \\'equilibres au repos: Q=0. Le sch\\'ema introduit est test\\'e sur des solutions analytiques.
A Coupled Model of the 1D River Network and 3D Estuary Based on Hydrodynamics and Suspended Sediment Simulation
Directory of Open Access Journals (Sweden)
Wei Zhang
Full Text Available River networks and estuaries are very common in coastal areas. Runoff from the upper stream interacts with tidal current from open sea in these two systems, leading to a complex hydrodynamics process. Therefore, it is necessary to consider the two systems as a whole to study the flow and suspended sediment transport. Firstly, a 1D model is established in the Pearl River network and a 3D model is applied in its estuary. As sufficient mass exchanges between the river network and its estuary, a strict mathematical relationship of water level at the interfaces can be adopted to couple the 1D model with the 3D model. By doing so, the coupled model does not need to have common nested grids. The river network exchanges the suspended sediment with its estuary by adding the continuity conditions at the interfaces. The coupled model is, respectively, calibrated in the dry season and the wet season. The results demonstrate that the coupled model works excellently in simulating water level and discharge. Although there are more errors in simulating suspended sediment concentration due to some reasons, the coupled model is still good enough to evaluate the suspended sediment transport in river network and estuary systems.
Development of 1D and 2D coupled model to simulate urban inundation: An application to Beijing Olympic Village
Institute of Scientific and Technical Information of China (English)
LI WeiFeng; CHEN QiuWen; MAO JingQiao
Urban inundation due to anomalous storms is a serious problem for many cities worldwide. Therefore, it is important to accurately simulate urban hydrological processes and efficiently predict the potential risks of urban floods for the improvement of drainage designs and implementation of emergency ac-tions. However, the complexity of urban landforma and the diversity of hydraulic infrastructure pose particular challenges for the simulation and risk assessment of urban drainage processes. This study developed a methodology to comprehensively simulate inundation processes by dynamically coupling 1D and 2D hydrodynamic models. By allowing the simultaneous solution of the processes of rainfall and runoff, urban drainage, and flooding, this method can be used to estimate the potential inundation risks of any designed drainage system. Furthermore, a Geographical Information System (GIS) based platform was fully integrated with the model engine to effectively illustrate the context of the problem. The developed model was then demonstrated on the Beijing 2008 Olympic Village under the conditions of the 5-year and 50-year design storms. The sewer discharge, channel discharge, and flood propaga-tion (inundation initiation, extent, depths, and duration) were numerically validated and analyzed. The results identified the potential inundation risks. From the study, it is found that the coupled GIS and 1D and 2D hydrodynamic models have the potential to simulate urban inundation processes, and hence efficiently predict flood risks and support cost-effective drainage design and management. It also im-plies promising prospects about the wide availability of high quality digital data, GIS techniques, and well-developed monitoring infrastructure to develop online urban inundation forecasts.
Non-linear simulations of combustion instabilities with a quasi-1D Navier-Stokes code
Haugen, Nils Erland L; Sannan, Sigurd
As lean premixed combustion systems are more susceptible to combustion instabilities than non-premixed systems, there is an increasing demand for improved numerical design tools that can predict the occurrence of combustion instabilities with high accuracy. The inherent non-linearities in combustion instabilities can be of crucial importance, and we here propose an approach in which the one-dimensional Navier-Stokes and scalar transport equations are solved for geometries of variable cross-section. The focus is on attached flames, and for this purpose a new phenomenological model for the unsteady heat release from a flame front is introduced. In the attached flame method (AFM) the heat release occurs over the full length of the flame. The non-linear code with the use of the AFM approach is validated against results from an experimental study of thermoacoustic instabilities in oxy-fuel flames by Ditaranto and Hals [Combustion and Flame, 146, 493-512 (2006)]. The numerical simulations are in accordance with the...
Simulation of the Efficiency of CdS/CIGS Tandem Multi-Junction Solar Cells Using AMPS-1D
Mirkamali, Ashrafalsadat S
In this paper we conduct numerical simulation of CdS/CIGS solar cells by use of the AMPS-1D software aiming to formulate the optimal design of the new multi-junction tandem solar cell providing its most efficient operation. We start with the numerical simulation of single-junction CdS/CIGS solar cells, which shows that its highest efficiency of 17.3% could be achieved by the thickness of CIGS p-layer of 200 nm. This result is in a good agreement with experimental data where the highest efficiency was 17.1% with the solar cell thickness of 1 micron. By use of the results of the numerical simulation of the single-junction solar cells we developed the design and conducted optimization of the new multi-junction tandem CdS/CIGS solar cell structure. Numerical simulation shows that the maximum efficiency of this solar cell is equal to 48.3%, which could be obtained with the thickness of the CIGS p-layer of 600 nm at a standard illumination of AM 1.5.
Fast electron propagation in high-density plasmas created by 1D shock wave compression: Experiments and simulations
Energy Technology Data Exchange (ETDEWEB)
Santos, J J; Dorchies, F; Dubrouil, A; Fourment, C; Hulin, S; D' Humieres, E; Nicolai, P H; Tikhonchuk, V [Universite Bordeaux 1, CELIA, Talence (France); Batani, D; Carpeggiani, P; Veltcheva, M [Dipartimento di Fisica ' G. Occhialini' , University degli Studi di Milano-Bicocca, Milan (Italy); McKenna, P; Quinn, M N [SUPA, Department of Physics, University of Strathclyde, Glasgow (United Kingdom); Baton, S D; Brambrink, E [LULI, Ecole Poly technique - CNRS - CEA, Palaiseau (France); Gremillet, L [CEA-DPTA, Bruyeres-le-Chatel (France); Debayle, A; Honrubia, J J, E-mail: email@example.com [GIFI, Universidad Politecnica, Madrid (Spain)
We present results from an experimental characterization of fast electron transport in high density plasmas created by 1D shock wave compression. The K{alpha} fluorescence from a Cu layer embedded in Al or CH foil targets is measured. We use long laser pulses (LP) with 180 J, 1.5 ns, 0.53{mu}m to compress the foils by shock wave propagation to 2-3 times their solid density and heat them to {approx} 4eV (close to the Fermi temperature). A counter-propagating high-intensity short laser pulse (SP), with 40 J, 1 ps, 57x10{sup 19} Wcm{sup -2}, generates intense currents of fast electrons which propagate through the deep regions of the target just before shock breakthrough. The results are compared to the uncompressed, solid density case (without the LP beam). The complete set of measurements is compared to numerical results, including a 2D hydrodynamic description of the compression and pre-pulse effects, 2D PIC simulations of the SP beam interaction and both hybrid and PIC simulations of the electron transport in the target depth and sheaths. In the case of the non-compressed targets we need to take fast electron refluxing into account to reproduce the experimental results. By exploring the domain of warm temperatures, we identify a regime for the incident fast electron current density, 10{sup 10} < jh < 10{sup 12} Acm{sup -2}, for which the collective mechanisms of electron transport differs appreciably between solid density and compressed matter.
A 1D-ecosystem model for pelagic waters in the southern Baltic Sea. Numerical simulations (future decades)
Dzierzbicka-Glowacka, L.; Maciejewska, A.; Osiński, R.; Jakacki, J.; Jędrasik, J.
This paper presents a one-dimensional Ecosystem Model. Mathematically, the pelagic variables in the model are described by a second-order partial differential equation of the diffusion type with biogeochemical sources and sinks. The temporal changes in the phytoplankton biomass are caused by primary production, respiration, mortality, grazing by zooplankton and sinking. The zooplankton biomass is affected by ingestion, excretion, respiration, fecal production, mortality, and carnivorous grazing. The changes in the pelagic detritus concentration are determined by input of: dead phytoplankton and zooplankton, natural mortality of predators, fecal pellets, and sinks: sedimentation, zooplankton grazing and decomposition. The nutrient concentration is caused by nutrient release, zooplankton excretion, predator excretion, detritus decomposition and benthic regeneration as sources and by nutrient uptake by phytoplankton as sinks. However, the benthic detritus is described by phytoplankton sedimentation, detritus sedimentation and remineralisation. The particulate organic carbon concentration is determined as the sum of phytoplankton, zooplankton and dead organic matter (detritus) concentrations. The 1D ecosystem model was used to simulate the seasonal dynamics of pelagic variables (phytoplankton, zooplankton, pelagic detritus and POC) in the southern Baltic Sea (Gdańsk Deep, Bornholm Deep and Gotland Deep). The calculations were made assuming: 1) increase in the water temperature in the upper layer - 0.008oC per year, 2) increase in the available light - 0.2% per year. Based on this trend, daily, monthly and seasonal and annual variability of phytoplankton, zooplankton, pelagic detritus and particulate organic carbon in different areas of the southern Baltic Sea (Gdańsk Deep, Borrnholm Deep and Gotland Deep) in the euphotic layer was calculated for the years: 2000, 2010, 2020, 2030, 2040 and 2050.
利用COMSOL软件对1D-BPM电极影响的仿真及分析%Simulation Based on COMSOL for Effect of Electrode Configuration on 1D-BPM
Institute of Scientific and Technical Information of China (English)
高文宏; 马树元
One-dimensional dimension binary-code phase modulator (1D-BPM) for speckle reduction in laser display system is designed based on Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT) and microelectromechnical system (MEMS) microfabrication technology.Mathematical model of 1D-BPM is built up,and the relationship between phase shift and electrical field applied by electrodes is deduced.Electrode configuration is investigated by simulation with finite element analysis.We find that the phase distribution across the gap between two electrodes depends not only on the electric field applied by electrodes,but also on the electrodes' configuration when their dimensions are on the submicron order.Electrodes corner effect is the significant factors for device design and optimization.%基于微机电系统(MEMS)微加工技术和Pb( Mg1/3 Nb2/3) O3-PbTiO3 (PMN-PT)电光材料设计的一维二进制码相位调制器(1D-BPM)可用于激光显示技术中的散斑消除.建立了1D-BPM数学模型,推导出电极在PMN-PT片内产生的电场和PMN-PT折射率变化导致通过的光束相位变化的关系.采用有限元分析方法仿真了电极几何尺寸对相位的影响,发现当电极尺寸在亚微米级时,两电极间相位分布不仅依赖于电极产生的电场大小,而且受到电极几何尺寸的影响.电极角效应是器件设计及优化时需考虑的重要因素.
Simulation of unsteady state performance of a secondary air system by the 1D-3D-Structure coupled method
Wu, Hong; Li, Peng; Li, Yulong
This paper describes the calculation method for unsteady state conditions in the secondary air systems in gas turbines. The 1D-3D-Structure coupled method was applied. A 1D code was used to model the standard components that have typical geometric characteristics. Their flow and heat transfer were described by empirical correlations based on experimental data or CFD calculations. A 3D code was used to model the non-standard components that cannot be described by typical geometric languages, while a finite element analysis was carried out to compute the structural deformation and heat conduction at certain important positions. These codes were coupled through their interfaces. Thus, the changes in heat transfer and structure and their interactions caused by exterior disturbances can be reflected. The results of the coupling method in an unsteady state showed an apparent deviation from the existing data, while the results in the steady state were highly consistent with the existing data. The difference in the results in the unsteady state was caused primarily by structural deformation that cannot be predicted by the 1D method. Thus, in order to obtain the unsteady state performance of a secondary air system more accurately and efficiently, the 1D-3D-Structure coupled method should be used.
Seismic Wave Amplification in 3D Alluvial Basins: 3D/1D Amplification Ratios from Fast Multipole BEM Simulations
Fajardo, Kristel C Meza; Chaillat, Stéphanie; Lenti, Luca
In this work, we study seismic wave amplification in alluvial basins having 3D standard geometries through the Fast Multipole Boundary Element Method in the frequency domain. We investigate how much 3D amplification differs from the 1D (horizontal layering) case. Considering incident fields of plane harmonic waves, we examine the relationships between the amplification level and the most relevant physical parameters of the problem (impedance contrast, 3D aspect ratio, vertical and oblique incidence of plane waves). The FMBEM results show that the most important parameters for wave amplification are the impedance contrast and the so-called equivalent shape ratio. Using these two parameters, we derive simple rules to compute the fundamental frequency for various 3D basin shapes and the corresponding 3D/1D amplification factor for 5% damping. Effects on amplification due to 3D basin asymmetry are also studied and incorporated in the derived rules.
Simulation of Hetero-junction (GaInP/GaAs Solar Cell Using AMPS-1D
Directory of Open Access Journals (Sweden)
Dennai Benmoussa
Full Text Available Photovoltaic conversion is the direct conversion of electromagnetic energy into electrical energy continuously. This electromagnetic energy is the most solar radiation. In this work we performed a computer modelling using AMPS 1D optimization of hetero-junction solar cells GaInP / GaAs configuration for p/n. We studied the influence of the thickness the base layer in the cell offers on the open circuit voltage, the short circuit current and efficiency.
Simulation of Hetero-junction (GaInP/GaAs) Solar Cell Using AMPS-1D
Dennai Benmoussa; M. Boukais; H. Benslimane
Photovoltaic conversion is the direct conversion of electromagnetic energy into electrical energy continuously. This electromagnetic energy is the most solar radiation. In this work we performed a computer modelling using AMPS 1D optimization of hetero-junction solar cells GaInP / GaAs configuration for p/n. We studied the influence of the thickness the base layer in the cell offers on the open circuit voltage, the short circuit current and efficiency.
Quantum simulation of 2d topological physics using orbital-angular-momentum-carrying photons in a 1d array of cavities
Luo, Xi-Wang; Li, Chuan-Feng; Xu, Jin-Shi; Guo, Guang-Can; Zhou, Zheng-Wei
Orbital angular momentum (OAM) of light is a fundamental optical degree of freedom that has recently motivated much exciting research in diverse fields ranging from optical communication to quantum information. We show for the first time that it is also a unique and valuable resource for quantum simulation, by demonstrating theoretically how \\emph{2d} topological physics can be simulated in a \\emph{1d} array of optical cavities using OAM-carrying photons. Remarkably, this newly discovered application of OAM states not only reduces required physical resources but also increases feasible scale of simulation. By showing how important topics such as edge-state transport and topological phase transition can be studied in a small simulator with just a few cavities ready for immediate experimental exploration, we demonstrate the prospect of photonic OAM for quantum simulation which can have a significant impact on the research of topological physics.
Comparison between a coupled 1D-2D model and a fully 2D model for supercritical flow simulation in crossroads
Ghostine, Rabih
In open channel networks, flow is usually approximated by the one-dimensional (1D) Saint-Venant equations coupled with an empirical junction model. In this work, a comparison in terms of accuracy and computational cost between a coupled 1D-2D shallow water model and a fully two-dimensional (2D) model is presented. The paper explores the ability of a coupled model to simulate the flow processes during supercritical flows in crossroads. This combination leads to a significant reduction in the computational time, as a 1D approach is used in branches and a 2D approach is employed in selected areas only where detailed flow information is essential. Overall, the numerical results suggest that the coupled model is able to accurately simulate the main flow processes. In particular, hydraulic jumps, recirculation zones, and discharge distribution are reasonably well reproduced and clearly identified. Overall, the proposed model leads to a 30% reduction in run times. © 2014 International Association for Hydro-Environment Engineering and Research.
Simulation Study on the Open-Circuit Voltage of Amorphous Silicon p-i-n Solar Cells Using AMPS-1D
Directory of Open Access Journals (Sweden)
B.M. Omer
Full Text Available AMPS-1D (Analysis of Microelectronic and Photonic Structure simulation program was used to simulate Amorphous Silicon p-i-n Solar Cell. The simulated result of illuminated current density-voltage characteristics was in a good agreement with experimental values. The dependence of the open-circuit voltage on the characteristics of the a-Si:H intrinsic layer was investigated. The simulation result shows that the open-circuit voltage does not depend on the thickness of the intrinsic layer. The open-circuit voltage decreases when the front contact barrier height is small or the energy gap of the intrinsic layer is small. The open-circuit voltage increases when the distribution of the tail states is sharp or the capture cross sections of these states are small.
Development of a coupled 1D-3D thermal-hydraulic code for nuclear power plant simulation and its application to a pressurized thermal shock scenario in PWR
International Nuclear Information System (INIS)
Thermal-hydraulic (TH) system codes are developed for the evaluation and improvement of the design and safety of nuclear facilities. Since the numerical modeling of the thermal-hydraulic processes is 1D in nature, these programs have only limited capabilities to predict in detail 3D flows and coolant mixing processes. In contrast, computational fluid dynamics (CFD) software tools are used for 3D flow calculations with high spatial resolution. In order to realistically and efficiently simulate the thermal-hydraulic phenomena in a nuclear power plant (NPP), GRS has developed a methodology for the coupling of the TH system code ATHLET with the 3D CFD software ANSYS CFX. Within the European project NURISP validation activities for the 1D-3D code ATHLET - ANSYS CFX based on a Pressurized Thermal Shock (PTS) related experiment are performed. (author)
Simulation of Marine Boundary Layer characteristics using a 1-D PBL model over the Bay of Bengal during BOBMEX-99
Indian Academy of Sciences (India)
N V Sam; U C Mohanty; A N V Satyanarayana
The characteristic features of the marine boundary layer (MBL) over the Bay of Bengal during the southwest monsoon and the factors influencing it are investigated. The Bay of Bengal and Monsoon Experiment (BOBMEX) carried out during July-August 1999 is the first observational experiment under the Indian Climate Research Programme (ICRP). A very high-resolution data in the vertical was obtained during this experiment, which was used to study the MBL characteristics off the east coast of India in the north and south Bay of Bengal. Spells of active and suppressed convection over the Bay were observed, of which, three representative convective episodes were considered for the study. For this purpose a one-dimensional multi-level PBL model with a TKE- closure scheme was used. The soundings, viz., the vertical profiles of temperature, humidity, zonal and meridional component of wind, obtained onboard ORV Sagar Kanya and from coastal stations along the east coast are used for the study. The temporal evolution of turbulent kinetic energy, marine boundary layer height (MBLH), sensible and latent heat fluxes and drag coefficient of momentum are simulated for different epochs of monsoon and monsoon depressions during BOBMEX-99.The model also generates the vertical profiles of potential temperature, specific humidity, zonal and meridional wind. These simulated values compared reasonably well with the observations available from BOBMEX.
Simulation of decay heat removal by natural convection in a pool type fast reactor model-ramona-with coupled 1D/2D thermal hydraulic code system
Energy Technology Data Exchange (ETDEWEB)
Kasinathan, N.; Rajakumar, A.; Vaidyanathan, G.; Chetal, S.C. [Indira Gandhi Centre for Atomic Research, Kalpakkam (India)
Post shutdown decay heat removal is an important safety requirement in any nuclear system. In order to improve the reliability of this function, Liquid metal (sodium) cooled fast breeder reactors (LMFBR) are equipped with redundant hot pool dipped immersion coolers connected to natural draught air cooled heat exchangers through intermediate sodium circuits. During decay heat removal, flow through the core, immersion cooler primary side and in the intermediate sodium circuits are also through natural convection. In order to establish the viability and validate computer codes used in making predictions, a 1:20 scale experimental model called RAMONA with water as coolant has been built and experimental simulation of decay heat removal situation has been performed at KfK Karlsruhe. Results of two such experiments have been compiled and published as benchmarks. This paper brings out the results of the numerical simulation of one of the benchmark case through a 1D/2D coupled code system, DHDYN-1D/THYC-2D and the salient features of the comparisons. Brief description of the formulations of the codes are also included.
The influence of negative ions in helium-oxygen barrier discharges: II. 1D fluid simulation and adaption to the experiment
Nemschokmichal, Sebastian; Tschiersch, Robert; Meichsner, Jürgen
A 1D fluid simulation was developed to investigate the influence of negative ions in a helium-oxygen barrier discharge between two glass plates at a distance of 3~\\text{mm} . The paper describes setting up the simulation for a pressure of 500~\\text{mbar} and an admixture of 400~\\text{ppm} oxygen to helium. In order to enable the comparison with laser photodetachment experiments, the simulation is adapted to the experimentally observed discharge current and gap voltage by varying gas temperature, flux of thermally desorpted electrons and secondary electron emission coefficients. The discharge is characterized by evaluation of the most important elementary collision processes as well as the kinetics of the charged species. Besides, the influence of long-living species on the discharge behavior is taken into account by long-time simulations. The negative ions are characterized by their spatio-temporal distribution in the gap and their production and loss processes. The comparison between simulations without and with consideration of negative ions reveals the importance of negative ions on the discharge development.
Extension of the simulation capabilities of the 1D system code ATHLET by coupling with the 3D CFD software package ANSYS CFX
International Nuclear Information System (INIS)
The thermal-hydraulic system code ATHLET (Analysis of THermal-hydraulics of LEaks and Transients) is developed at Gesellschaft fuer Anlagen- und Reaktorsicherheit (GRS) for the analysis of anticipated and abnormal plant transients, small and intermediate leaks as well as large breaks in light water reactors. The aim of the code development is to cover the whole spectrum of design basis and beyond design basis accidents (without core degradation) for PWRs and BWRs. In order to extend the simulation capabilities of the 1D system code ATHLET, different approaches are applied at GRS to enable multidimensional thermal-hydraulic representation of relevant primary circuit geometries. One of the current major strategies at the technical safety organization is the coupling of ATHLET with the commercial 3D Computational Fluid Dynamics (CFD) software package ANSYS CFX. This code is a general purpose CFD software program that combines an advanced solver with powerful pre- and post-processing capabilities. It is an efficient tool for simulating the behavior of systems involving fluid flow, heat transfer, and other related physical processes. In the frame of the German CFD Network on Nuclear Reactor Safety, GRS and ANSYS Germany developed a general computer interface for the coupling of both codes. This paper focuses on the methodology and the challenges related to the coupling process. A great number of simulations including test cases with closed loop configurations have been carried out to evaluate and improve the performance of the coupled code system. Selected results of the 1D-3D thermal-hydraulic calculations are presented and analyzed. Preliminary comparative calculations with CFX-ATHLET and ATHLET stand alone showed very good agreement. Nevertheless, an extensive validation of the developed coupled code is planned. Finally, the optimization potential of the coupling methodology is discussed. (author)
A 1-D simulation analysis of the development and maintenance of the 2001 red tide of the ichthyotoxic dinoflagellate Karenia brevis on the West Florida shelf
Lenes, J. M.; Darrow, B. P.; Walsh, J. J.; Jolliff, J. K.; Chen, F. R.; Weisberg, R. H.; Zheng, L.
A one-dimensional (1-D) ecological model, HABSIM, examined the initiation and maintenance of the 2001 red tide on the West Florida shelf (WFS). Phytoplankton competition among toxic dinoflagellates (Karenia brevis), nitrogen fixing cyanophytes (Trichodesmium erythraeum), large siliceous phytoplankton (diatoms), and small non-siliceous phytoplankton (microflagellates) explored the sequence of events required to support the observed red tide from August to December 2001. The ecological model contained 24 state variables within five submodels: circulation, atmospheric (iron deposition), bio-optics, pelagic (phytoplankton, nutrients, bacteria, zooplankton, and fish), and benthic (nutrient regeneration). The 2001 model results reaffirmed that diazotrophs are the basis for initiation of red tides of K. brevis on the WFS. A combination of selective grazing pressure, iron fertilization, low molar nitrogen to phosphorus ratios, and eventual silica limitation of fast-growing diatoms set the stage for dominance of nitrogen fixers. "New" nitrogen was made available for subsequent blooms of K. brevis through the release of ammonium and urea during nitrogen fixation, as well as during cell lysis, by the Trichodesmium population. Once K. brevis biomass reached ichthyotoxic levels, rapid decay of subsequent fish kills supplied additional organic nutrients for utilization by these opportunistic toxic algae. Both nutrient vectors represented organic non-siliceous sources of nitrogen and phosphorus, further exacerbating silica limitation of the diatom population. The model reproduced this spring transition from a simple estuarine-driven, diatom-based food chain to a complex summer-fall system of Trichodesmium and toxic dinoflagellates. While the model was able to replicate the initiation and maintenance of the 2001 red tide, bloom termination was not captured by this 1-D form on the WFS. Here, horizontal advection and perhaps cell lysis loss terms might play a significant role, to be
Experimental development, 1D CFD simulation and energetic analysis of a 15 kw micro-CHP unit based on reciprocating internal combustion engine
International Nuclear Information System (INIS)
Cogeneration is commonly recognized as one of the most effective solutions to achieve the increasingly stringent reduction in primary energy consumption and greenhouse emissions. This characteristic led to the adoption of specific directives promoting this technique. In addition, a strategic role in power reliability is recognized to distributed generation. The study and prototyping of cogeneration plants, therefore, has involved many research centres. This paper deals with energetic aspects of CHP referring to the study of a 15 kW micro-CHP plant based on a LPG reciprocating engine designed, built and grid connected. The plant consists of a heat recovery system characterized by a single water circuit recovering heat from exhaust gases, from engine coolant and from the energy radiated by the engine within the shell hosting the plant. Some tests were carried out at whole open throttle and the experimental data were collected. However it was needed to perform a 1D thermo-fluid dynamics simulation of the engine to completely characterize the micro-CHP. As the heat actually recovered depends on the user's thermal load, particularly from the required temperature's level, a comparison of the results for six types of users were performed: residential, hospital, office, commercial, sports, hotel. Both Italian legislative indexes IRE and LT were evaluated, as defined by A.E.E.G resolution n. 42/02 and subsequent updates, as well as the plant's total Primary Energy Saving. - Highlights: • This paper deals with energetic aspects of CHP referring to the study of a 15 kW micro-CHP plant. • The 15 kW micro-CHP plant is based on a GPL reciprocating engine designed, built and grid connected. • Some tests were carried out at whole open throttle and the experimental data were collected. • It was needed to perform a 1D thermo-fluid dynamics simulation of the engine to completely characterize the micro-CHP. • The analysed solution is particularly suited for
On the potential for CO2 mineral storage in continental flood basalts – PHREEQC batch- and 1D diffusion–reaction simulations
Directory of Open Access Journals (Sweden)
Van Pham Thi
Full Text Available Abstract Continental flood basalts (CFB are considered as potential CO2 storage sites because of their high reactivity and abundant divalent metal ions that can potentially trap carbon for geological timescales. Moreover, laterally extensive CFB are found in many place in the world within reasonable distances from major CO2 point emission sources. Based on the mineral and glass composition of the Columbia River Basalt (CRB we estimated the potential of CFB to store CO2 in secondary carbonates. We simulated the system using kinetic dependent dissolution of primary basalt-minerals (pyroxene, feldspar and glass and the local equilibrium assumption for secondary phases (weathering products. The simulations were divided into closed-system batch simulations at a constant CO2 pressure of 100 bar with sensitivity studies of temperature and reactive surface area, an evaluation of the reactivity of H2O in scCO2, and finally 1D reactive diffusion simulations giving reactivity at CO2 pressures varying from 0 to 100 bar. Although the uncertainty in reactive surface area and corresponding reaction rates are large, we have estimated the potential for CO2 mineral storage and identified factors that control the maximum extent of carbonation. The simulations showed that formation of carbonates from basalt at 40 C may be limited to the formation of siderite and possibly FeMg carbonates. Calcium was largely consumed by zeolite and oxide instead of forming carbonates. At higher temperatures (60 – 100 C, magnesite is suggested to form together with siderite and ankerite. The maximum potential of CO2 stored as solid carbonates, if CO2 is supplied to the reactions unlimited, is shown to depend on the availability of pore space as the hydration and carbonation reactions increase the solid volume and clog the pore space. For systems such as in the scCO2 phase with limited amount of water, the total carbonation potential is limited by the amount of water present
The 5-HT1D/1B receptor agonist sumatriptan enhances fear of simulated speaking and reduces plasma levels of prolactin.
de Rezende, Marcos Gonçalves; Garcia-Leal, Cybele; Graeff, Frederico Guilherme; Del-Ben, Cristina Marta
This study measured the effects of the preferential 5-HT1D/1B receptor agonist sumatriptan in healthy volunteers who performed the Simulated Public Speaking Test (SPST), which recruits the neural network involved in panic disorder and social anxiety disorder. In a double-blind, randomised experiment, 36 males received placebo (12), 50 mg (12) or 100 mg (12) of sumatriptan 2 h before the SPST. Subjective, physiological and hormonal measures were taken before, during and after the test. The dose of 100 mg of sumatriptan increased speech-induced fear more than either a 50mg dose of the drug or placebo. The largest dose of sumatriptan also enhanced vigilance more than placebo, without any change in blood pressure, heart rate or electrical skin conductance. Sumatriptan decreased plasma levels of prolactin. A significant but moderate increase in plasma cortisol after SPST occurred, independent of treatment. Because sumatriptan decreases 5-HT release into the extracellular space, the potentiation of SPST-induced fear caused by the drug supports the hypothesis that 5-HT attenuates this emotional state. As acute administration of antidepressants has also been shown to enhance speaking fear and increase plasma prolactin, in contrast to sumatriptan, the 5-HT regulation of stress-hormone release is likely to be different from that of emotion. PMID:23325368
The 5-HT1D/1B receptor agonist sumatriptan enhances fear of simulated speaking and reduces plasma levels of prolactin.
de Rezende, Marcos Gonçalves; Garcia-Leal, Cybele; Graeff, Frederico Guilherme; Del-Ben, Cristina Marta
This study measured the effects of the preferential 5-HT1D/1B receptor agonist sumatriptan in healthy volunteers who performed the Simulated Public Speaking Test (SPST), which recruits the neural network involved in panic disorder and social anxiety disorder. In a double-blind, randomised experiment, 36 males received placebo (12), 50 mg (12) or 100 mg (12) of sumatriptan 2 h before the SPST. Subjective, physiological and hormonal measures were taken before, during and after the test. The dose of 100 mg of sumatriptan increased speech-induced fear more than either a 50mg dose of the drug or placebo. The largest dose of sumatriptan also enhanced vigilance more than placebo, without any change in blood pressure, heart rate or electrical skin conductance. Sumatriptan decreased plasma levels of prolactin. A significant but moderate increase in plasma cortisol after SPST occurred, independent of treatment. Because sumatriptan decreases 5-HT release into the extracellular space, the potentiation of SPST-induced fear caused by the drug supports the hypothesis that 5-HT attenuates this emotional state. As acute administration of antidepressants has also been shown to enhance speaking fear and increase plasma prolactin, in contrast to sumatriptan, the 5-HT regulation of stress-hormone release is likely to be different from that of emotion.
Dynamics of ozone and nitrogen oxides at Summit, Greenland. II. Simulating snowpack chemistry during a spring high ozone event with a 1-D process-scale model
Murray, K.A.; Kramer, L.J.; Doskey, P.V.; Ganzeveld, L.N.; Seok, B.; Dam, van B.; Helmig, D.
Observed depth profiles of nitric oxide (NO), nitrogen dioxide (NO2), and ozone (O3) in snowpack interstitial air at Summit, Greenland were best replicated by a 1-D process-scale model, which included (1) geometrical representation of snow grains as spheres, (2) aqueous-phase chemistry confined to a
Pulse wave propagation in a model human arterial network: Assessment of 1-D visco-elastic simulations against in vitro measurements
Alastruey, Jordi; Khir, Ashraf W.; Matthys, Koen S.; Segers, Patrick; Sherwin, Spencer J.; Verdonck, Pascal R.; Parker, Kim H.; Peiro, Joaquim
The accuracy of the nonlinear one-dimensional (1-D) equations of pressure and flow wave propagation in Voigt-type visco-elastic arteries was tested against measurements in a well-defined experimental 1:1 replica of the 37 largest conduit arteries in the human systemic circulation. The parameters required by the numerical algorithm were directly measured in the in vitro setup and no data fitting was involved. The inclusion of wall visco-elasticity in the numerical model reduced the underdamped...
Near-infrared spectro-interferometry of Mira variables and comparisons to 1D dynamic model atmospheres and 3D convection simulations
Wittkowski, M; Freytag, B; Scholz, M; Hoefner, S; Karovicova, I; Whitelock, P A
We obtained a total of 20 near-infrared K-band spectro-interferometric snapshot observations of the Mira variables o Cet, R Leo, R Aqr, X Hya, W Vel, and R Cnc with a spectral resolution of about 1500. We compared observed flux and visibility spectra with predictions by CODEX 1D dynamic model atmospheres and with azimuthally averaged intensities based on CO5BOLD 3D dynamic model atmospheres including convection. Our visibility data confirm the presence of spatially extended molecular atmospheres located above the continuum radii with large-scale inhomogeneities or clumps that contribute a few percent of the total flux. The detailed structure of the inhomogeneities or clumps show a variability on time scales of 3 months and above. Both modeling attempts provided satisfactory fits to our data. In particular, they are both consistent with the observed decrease in the visibility function at molecular bands of water vapor and CO, indicating a spatially extended molecular atmosphere. Observational variability phase...
Part i: Lie-Backlund Theory and Linearization of Differential Equations. Part II: Monte Carlo Simulations of 1-D Quantum Spin Models.
Cullen, John J.
Part I begins with an account of groups of Lie -Back-lund (L-B) tangent transformations; it is then shown that L-B symmetry operators depending on integrals (nonlocal variables), such as discussed by Konopelchenko and Mokhnachev (1979), are related by change of variables to the L-B operators which involve no more than derivatives. A general method is set down for transforming a given L-B operator into a new one, by any invertible transformation depending on (. . ., D(,x)('-1) u, u, u(,x), . . .). It is shown that once a given differential equation admits a L-B operator, there is in general a very large number of related ("secondary") equations which admit the same operator. The L-B Theory involving nonlocal variables is used to characterize group theoretically the linearization both of the Burgers equation, u(,t) + uu(,x) - u(,xx) = 0, and of the o.d.e. u(,xx) + (omega)('2)(x)u + Ku('-3) = 0. Secondary equations are found to play an important role in understanding the group theoretical background to the linearization of differential equations. Part II deals with Monte Carlo simulations of the l-d quantum Heisenberg and XY-models, using an approach suggested by Suzuki (1976). The simulation is actually carried out on a 2-d, m x N, Isinglike system, equivalent to the original N-spin quantum system when m (--->) (INFIN). The results for m (LESSTHEQ) 10 and kT/(VBAR)J(VBAR) (GREATERTHEQ) .0125 are good enough to show that the method is generally applicable to quantum spin models; however some difficulties caused by singular bonding in the classical lattice (Wiesler 1982) and by the generation of unwanted states have to be taken into account in practice. The finite-size scaling method of Fisher and Ferdinard is adapted for use near T = 0 in the ferromagnetic Heisenberg model; applied to the simulation data it shows that the low temperature susceptibiltiy behaves at T('-(gamma)), where (gamma) = 1.32 (+OR-) 10%. Also, simple and potentially useful finite-size scaling
Air-snowpack exchange of bromine, ozone and mercury in the springtime Arctic simulated by the 1-D model PHANTAS - Part 2: Mercury and its speciation
Toyota, K.; Dastoor, A. P.; Ryzhkov, A.
Atmospheric mercury depletion events (AMDEs) refer to a recurring depletion of mercury occurring in the springtime Arctic (and Antarctic) boundary layer, in general, concurrently with ozone depletion events (ODEs). To close some of the knowledge gaps in the physical and chemical mechanisms of AMDEs and ODEs, we have developed a one-dimensional model that simulates multiphase chemistry and transport of trace constituents throughout porous snowpack and in the overlying atmospheric boundary layer (ABL). This paper constitutes Part 2 of the study, describing the mercury component of the model and its application to the simulation of AMDEs. Building on model components reported in Part 1 ("In-snow bromine activation and its impact on ozone"), we have developed a chemical mechanism for the redox reactions of mercury in the gas and aqueous phases with temperature dependent reaction rates and equilibrium constants accounted for wherever possible. Thus the model allows us to study the chemical and physical processes taking place during ODEs and AMDEs within a single framework where two-way interactions between the snowpack and the atmosphere are simulated in a detailed, process-oriented manner. Model runs are conducted for meteorological and chemical conditions that represent the springtime Arctic ABL characterized by the presence of "haze" (sulfate aerosols) and the saline snowpack on sea ice. The oxidation of gaseous elemental mercury (GEM) is initiated via reaction with Br-atom to form HgBr, followed by competitions between its thermal decomposition and further reactions to give thermally stable Hg(II) products. To shed light on uncertain kinetics and mechanisms of this multi-step oxidation process, we have tested different combinations of their rate constants based on published laboratory and quantum mechanical studies. For some combinations of the rate constants, the model simulates roughly linear relationships between the gaseous mercury and ozone concentrations as
Air-snowpack exchange of bromine, ozone and mercury in the springtime Arctic simulated by the 1-D model PHANTAS – Part 2: Mercury and its speciation
Directory of Open Access Journals (Sweden)
K. Toyota
Full Text Available Atmospheric mercury depletion events (AMDEs refer to a recurring depletion of mercury in the springtime Arctic (and Antarctic boundary layer, occurring, in general, concurrently with ozone depletion events (ODEs. To close some of the knowledge gaps in the physical and chemical mechanisms of AMDEs and ODEs, we have developed a one-dimensional model that simulates multiphase chemistry and transport of trace constituents throughout porous snowpack and in the overlying atmospheric boundary layer (ABL. Building on the model reported in a companion paper (Part 1: In-snow bromine activation and its impact on ozone, we have expanded the chemical mechanism to include the reactions of mercury in the gas- and aqueous-phases with temperature dependence of rate and equilibrium constants accounted for wherever possible. Thus the model allows us to study the chemical and physical processes taking place during ODEs and AMDEs within a single framework where two-way interactions between the snowpack and the atmosphere are simulated in a detailed, process-oriented manner. Model runs are conducted for meteorological and chemical conditions representing the springtime Arctic ABL loaded with "haze" sulfate aerosols and the underlying saline snowpack laid on sea ice. Using recent updates for the Hg + Br ⇄ HgBr reaction kinetics, we show that the rate and magnitude of photochemical loss of gaseous elemental mercury (GEM during AMDEs exhibit a strong dependence on the choice of reaction(s of HgBr subsequent to its formation. At 253 K, the temperature that is presumably low enough for bromine radical chemistry to cause prominent AMDEs as indicated from field observations, the parallel occurrence of AMDEs and ODEs is simulated if the reaction HgBr + BrO is assumed to produce a thermally stable intermediate, Hg(OBrBr, at the same rate constant as the reaction HgBr + Br. On the contrary, the simulated depletion of atmospheric mercury is notably diminished by
International Nuclear Information System (INIS)
We witnessed an initial hyped period and enthusiasm on carbon nano tubes in the 1990s later went through a significant expansion into nano tubes of other materials (metal di chalcogenides, boron nitride, etc.) as well as various nano wires and nano rods. While much of the hype might have gone, the research on one-dimensional (1D) nano materials has matured as one of the most active research areas within the nano science and nano technology community, flourishing with ample, exciting, and new research opportunities. Just like any other research frontier, researchers working in the 1D nano materials field are constantly striving to develop new fundamental science as well as potential applications. It remains a common belief that versatility and tunability of 1D nano materials would challenge many new rising tasks coming from our resource and energy demanding modern society. The traditional semiconductor industry has produced so many devices and systems from transistors, sensors, lasers, and LEDs to more sophisticated solar panels, which are now part of our daily lives. By down sizing the core components or parts to 1D form, one might wonder how fundamentally the dimensionality and morphology would impact the device performance, this is, as always, requiring us to fully understand the structure-property relationship in 1D nano materials. It may be equally crucial in connecting discovery-driven fundamental science to market-driven technology industry concerning potentially relevant findings derived from these novel materials. The importance of a platform that allows active researchers in this field to present their new development in a timely and efficient manner is therefore self-evident. Following the success of two early special issues devoted to 1D nano materials, this is the third one in a row organized by the same group of guest editors, attesting that such a platform has been well received by the readers
Energy Technology Data Exchange (ETDEWEB)
KALYANAPU, ALFRED [Los Alamos National Laboratory; MCPHERSON, TIMOTHY N. [Los Alamos National Laboratory; BURIAN, STEVEN J. [NON LANL
This paper presents a GIS-based 1-d distributed overland flow model and summarizes an application to simulate a flood event. The model estimates infiltration using the Green-Ampt approach and routes excess rainfall using the 1-d diffusive wave approximation. The model was designed to use readily available topographic, soils, and land use/land cover data and rainfall predictions from a meteorological model. An assessment of model performance was performed for a small catchment and a large watershed, both in urban environments. Simulated runoff hydrographs were compared to observations for a selected set of validation events. Results confirmed the model provides reasonable predictions in a short period of time.
One-Dimensional (1-D) Nanoscale Heterostructures
Institute of Scientific and Technical Information of China (English)
Guozhen SHEN; Di CHEN; Yoshio BANDO; Dmitri GOLBERG
One-dimensional (1-D) nanostructures have been attracted much attention as a result of their exceptional properties, which are different from bulk materials. Among 1-D nanostructures, 1-D heterostructures with modulated compositions and interfaces have recently become of particular interest with respect to potential applications in nanoscale building blocks of future optoelectronic devices and systems. Many kinds of methods have been developed for the synthesis of 1-D nanoscale heterostructures. This article reviews the most recent development, with an emphasize on our own recent efforts, on 1-D nanoscale heterostructures, especially those synthesized from the vapor deposition methods, in which all the reactive precursors are mixed together in the reaction chamber. Three types of 1-D nanoscale heterostructures, defined from their morphologies characteristics, are discussed in detail, which include 1-D co-axial core-shell heterostructures, 1-D segmented heterostructures and hierarchical heterostructures. This article begins with a brief survey of various methods that have been developed for synthesizing 1-D nanoscale heterostructures and then mainly focuses on the synthesis, structures and properties of the above three types of nanoscale heterostructures. Finally, this review concludes with personal views towards the topic of 1-D nanoscale heterostructures.
Benchmarking of a 1D Scrape-off layer code SOLF1D with SOLPS and its use in modelling long-legged divertors
Havlickova, E; Subba, F; Coster, D; Wischmeier, M; Fishpool, G
A 1D code modelling SOL transport parallel to the magnetic field (SOLF1D) is benchmarked with 2D simulations of MAST-U SOL performed via the SOLPS code for two different collisionalities. Based on this comparison, SOLF1D is then used to model the effects of divertor leg stretching in 1D, in support of the planned Super-X divertor on MAST. The aim is to separate magnetic flux expansion from volumetric power losses due to recycling neutrals by stretching the divertor leg either vertically or radially.
A 1D wavelet filtering for ultrasound images despeckling
Dahdouh, Sonia; Dubois, Mathieu; Frenoux, Emmanuelle; Osorio, Angel
Ultrasound images appearance is characterized by speckle, shadows, signal dropout and low contrast which make them really difficult to process and leads to a very poor signal to noise ratio. Therefore, for main imaging applications, a denoising step is necessary to apply successfully medical imaging algorithms on such images. However, due to speckle statistics, denoising and enhancing edges on these images without inducing additional blurring is a real challenging problem on which usual filters often fail. To deal with such problems, a large number of papers are working on B-mode images considering that the noise is purely multiplicative. Making such an assertion could be misleading, because of internal pre-processing such as log compression which are done in the ultrasound device. To address those questions, we designed a novel filtering method based on 1D Radiofrequency signal. Indeed, since B-mode images are initially composed of 1D signals and since the log compression made by ultrasound devices modifies noise statistics, we decided to filter directly the 1D Radiofrequency signal envelope before log compression and image reconstitution, in order to conserve as much information as possible. A bi-orthogonal wavelet transform is applied to the log transform of each signal and an adaptive 1D split and merge like algorithm is used to denoise wavelet coefficients. Experiments were carried out on synthetic data sets simulated with Field II simulator and results show that our filter outperforms classical speckle filtering methods like Lee, non-linear means or SRAD filters.
Optical properties of LEDs with patterned 1D photonic crystal
Hronec, P.; Kuzma, A.; Å kriniarová, J.; Kováč, J.; Benčurová, A.; Haščík, Å.; Nemec, P.
In this paper we focus on the application of the one-dimensional photonic crystal (1D PhC) structures on the top of Al0.295Ga0.705As/GaAs multi-quantum well light emitting diode (MQW LED). 1D PhC structures with periods of 600 nm, 700 nm, 800 nm, and 900 nm were fabricated by the E-Beam Direct Write (EBDW) Lithography. Effect of 1D PhC period on the light extraction enhancement was studied. 1D PhC LED radiation profiles were obtained from Near Surface Light Emission Images (NSLEI). Measurements showed the strongest light extraction enhancement using 800 nm period of PhC. Investigation of PhC LED radiation profiles showed strong light decoupling when light reaches PhC structure. Achieved LEE was from 22.6% for 600 nm PhC LED to 47.0% for 800 nm PhC LED. LED with PhC structure at its surface was simulated by FDTD simulation method under excitation of appropriate launch field.
Air-snowpack exchange of bromine, ozone and mercury in the springtime Arctic simulated by the 1-D model PHANTAS – Part 1: In-snow bromine activation and its impact on ozone
Directory of Open Access Journals (Sweden)
K. Toyota
Full Text Available To provide a theoretical framework towards better understanding of ozone depletion events (ODEs and atmospheric mercury depletion events (AMDEs in the polar boundary layer, we have developed a one-dimensional model that simulates multiphase chemistry and transport of trace constituents from porous snowpack and through the atmospheric boundary layer (ABL as a unified system. In this paper, we describe a general configuration of the model and the results of simulations related to reactive bromine release from the snowpack and ODEs during the Arctic spring. The model employs a chemical mechanism adapted from the one previously used for the simulation of multiphase halogen chemistry involving deliquesced sea-salt aerosols in the marine boundary layer. A common set of aqueous-phase reactions describe chemistry both in the liquid-like (or brine layer on the grain surface of the snowpack and in "haze" aerosols mainly composed of sulfate in the atmosphere. The process of highly soluble/reactive trace gases, whether entering the snowpack from the atmosphere or formed via gas-phase chemistry in the snowpack interstitial air (SIA, is simulated by the uptake on brine-covered snow grains and subsequent reactions in the aqueous phase while being traveled vertically within the SIA. A "bromine explosion", by which, in a conventional definition, HOBr formed in the ambient air is deposited and then converted heterogeneously to Br2, is a dominant process of reactive bromine formation in the top 1 mm (or less layer of the snowpack. Deeper in the snowpack, HOBr formed within the SIA leads to an in-snow bromine explosion, but a significant fraction of Br2 is also produced via aqueous radical chemistry in the brine on the surface of the snow grains. These top- and deeper-layer productions of Br2 both contribute to the Br2 release into the atmosphere, but the deeper-layer production is found to be more important for the net outflux of reactive bromine. Although ozone
Air-snowpack exchange of bromine, ozone and mercury in the springtime Arctic simulated by the 1-D model PHANTAS - Part 1: In-snow bromine activation and its impact on ozone
Toyota, K.; McConnell, J. C.; Staebler, R. M.; Dastoor, A. P.
To provide a theoretical framework towards a better understanding of ozone depletion events (ODEs) and atmospheric mercury depletion events (AMDEs) in the polar boundary layer, we have developed a one-dimensional model that simulates multiphase chemistry and transport of trace constituents from porous snowpack and through the atmospheric boundary layer (ABL) as a unified system. This paper constitutes Part 1 of the study, describing a general configuration of the model and the results of simulations related to reactive bromine release from the snowpack and ODEs during the Arctic spring. A common set of aqueous-phase reactions describes chemistry both within the liquid-like layer (LLL) on the grain surface of the snowpack and within deliquesced "haze" aerosols mainly composed of sulfate in the atmosphere. Gas-phase reactions are also represented by the same mechanism in the atmosphere and in the snowpack interstitial air (SIA). Consequently, the model attains the capacity of simulating interactions between chemistry and mass transfer that become particularly intricate near the interface between the atmosphere and the snowpack. In the SIA, reactive uptake on LLL-coated snow grains and vertical mass transfer act simultaneously on gaseous HOBr, a fraction of which enters from the atmosphere while another fraction is formed via gas-phase chemistry in the SIA itself. A "bromine explosion", by which HOBr formed in the ambient air is deposited and then converted heterogeneously to Br2, is found to be a dominant process of reactive bromine formation in the top 1 mm layer of the snowpack. Deeper in the snowpack, HOBr formed within the SIA leads to an in-snow bromine explosion, but a significant fraction of Br2 is also produced via aqueous radical chemistry in the LLL on the surface of the snow grains. These top- and deeper-layer productions of Br2 both contribute to the release of Br2 to the atmosphere, but the deeper-layer production is found to be more important for the
First Observation of Upsilon(1D) States
Csorna, S E; Bonvicini, G; Cinabro, D; Dubrovin, M; McGee, S; Bornheim, A; Lipeles, E; Pappas, S P; Shapiro, A; Sun, W M; Weinstein, A J; Mahapatra, R; Briere, R A; Chen, G P; Ferguson, T; Tatishvili, G T; Vogel, H; Adam, N E; Alexander, J P; Berkelman, K; Boisvert, V; Cassel, David G; Drell, P S; Duboscq, J E; Ecklund, K M; Ehrlich, R; Galik, R S; Gibbons, L; Gittelman, B; Gray, S W; Hartill, D L; Heltsley, B K; Hsu, L; Jones, C D; Kandaswamy, J; Kreinick, D L; Magerkurth, A; Mahlke-Krüger, H; Meyer, T O; Mistry, N B; Nordberg, E; Patterson, J R; Peterson, D; Pivarski, J; Riley, D; Sadoff, A J; Schwarthoff, H; Shepherd, M R; Thayer, J G; Urner, D; Viehhauser, G; Warburton, A; Weinberger, M; Athar, S B; Avery, P; Breva-Newell, L; Potlia, V; Stöck, H; Yelton, J; Brandenburg, G; Kim, D Y J; Wilson, R; Benslama, K; Eisenstein, B I; Ernst, J; Gollin, G D; Hans, R M; Karliner, I; Lowrey, N; Plager, C; Sedlack, C; Selen, M; Thaler, J J; Williams, J; Edwards, K W; Ammar, R; Besson, D; Zhao, X; Anderson, S; Frolov, V V; Kubota, Y; Lee, S J; Li, S Z; Poling, R A; Smith, A; Stepaniak, C J; Urheim, J; Metreveli, Z V; Seth, K K; Tomaradze, A G; Zweber, P; Ahmed, S; Alam, M S; Jian, L; Saleem, M; Wappler, F; Eckhart, E; Gan, K K; Gwon, C; Hart, T; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Pedlar, T K; Thayer, J B; Von Törne, E; Wilksen, T; Zoeller, M M; Muramatsu, H; Richichi, S J; Severini, H; Skubic, P L; Dytman, S A; Müller, J A; Nam, S; Savinov, V; Chen, S; Hinson, J W; Lee, J; Miller, D H; Pavlunin, V; Shibata, E I; Shipsey, I P J; Cronin-Hennessy, D; Lyon, A L; Park, C S; Park, W; Thorndike, E H; Coan, T E; Gao, Y S; Liu, F; Maravin, Y; Stroynowski, R; Artuso, M; Boulahouache, C; Bukin, K; Dambasuren, E; Khroustalev, K; Mountain, R; Nandakumar, R; Skwarnicki, T; Stone, S; Wang, J C; Mahmood, A H
The CLEO III experiment has recently accumulated a large statistics sample of 4.73 x 10^6 Upsilon(3S) decays. We present the first evidence for the production of the triplet Upsilon(1D) states in the four-photon cascade, Upslion(3S) -> gamma chi_b(2P), chi_b(2P) -> gamma Upsilon(1D), Upsilon(1D) -> gamma chi_b(1P), chi_b(1P) -> gamma Upsilon(1S), followed by the Upsilon(1S) annihilation to e+ e- or mu+ mu-. The signal has a significance of 9.7 standard deviations. The measured product branching ratio for these five decays, (3.3 +- 0.6 +- 0.5) x 10^{-5}, is consistent with the theoretical estimates. We see a 6.8 standard deviation signal for a state with a mass of 10162.2 +- 1.6 MeV/c^2, consistent with the Upsilon(1D_2) assignment. We also present improved measurements of the Upsilon(3S) -> pi0 pi0 Upsilon(1S) branching ratio and the associated di-pion mass distribution.
YORP torques with 1D thermal model
Breiter, Slawomir; Czekaj, Maria
A numerical model of the Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) effect for objects defined in terms of a triangular mesh is described. The algorithm requires that each surface triangle can be handled independently, which implies the use of a 1D thermal model. Insolation of each triangle is determined by an optimized ray-triangle intersection search. Surface temperature is modeled with a spectral approach; imposing a quasi-periodic solution we replace heat conduction equation by the Helmholtz equation. Nonlinear boundary conditions are handled by an iterative, FFT based solver. The results resolve the question of the YORP effect in rotation rate independence on conductivity within the nonlinear 1D thermal model regardless of the accuracy issues and homogeneity assumptions. A seasonal YORP effect in attitude is revealed for objects moving on elliptic orbits when a nonlinear thermal model is used.
1D ferrimagnetism in homometallic chains
Coronado Miralles, Eugenio; Gómez García, Carlos José; Borrás Almenar, Juan José
The magnetic properties of the cobalt zigzag chain Co(bpy)(NCS)2 (bpy=2,2′‐bipyridine) are discussed on the basis of an Ising‐chain model that takes into account alternating Landé factors. It is emphasized, for the first time, that a homometallic chain containing only one type of site can give rise to a 1D ferrimagneticlike behavior. ,
Slug modeling with 1D two-fluid model
International Nuclear Information System (INIS)
Simulations of condensation-induced water hammer with one-dimensional two-fluid model requires explicit modeling of slug formation, slug propagation, and in some cases slug decay. Stratified flow correlations that are more or less well known in 1D two-fluid models, are crucial for accurate description of the initial phase of the slug formation and slug propagation. Slug formation means transition to other flow regime that requires different set of correlations. To use such two-fluid model for condensation induced water hammer simulations, a single slug must be explicitly recognized and captured. In the present work two cases of condensation-induced water hammer simulations performed with WAHA code, are described and discussed: injection of cold liquid into horizontal pipe filled with steam and injection of hot steam into horizontal pipe partially filled with cold liquid. (author)
Modeling atrazine transport in soil columns with HYDRUS-1D
Directory of Open Access Journals (Sweden)
John Leju CELESTINO LADU
Full Text Available Both physical and chemical processes affect the fate and transport of herbicides. It is useful to simulate these processes with computer programs to predict solute movement. Simulations were run with HYDRUS-1D to identify the sorption and degradation parameters of atrazine through calibration from the breakthrough curves (BTCs. Data from undisturbed and disturbed soil column experiments were compared and analyzed using the dual-porosity model. The study results show that the values of dispersivity are slightly lower in disturbed columns, suggesting that the more heterogeneous the structure is, the higher the dispersivity. Sorption parameters also show slight variability, which is attributed to the differences in soil properties, experimental conditions and methods, or other ecological factors. For both of the columns, the degradation rates were similar. Potassium bromide was used as a conservative non-reactive tracer to characterize the water movement in columns. Atrazine BTCs exhibited significant tailing and asymmetry, indicating non-equilibrium sorption during solute transport. The dual-porosity model was verified to best fit the BTCs of the column experiments. Greater or lesser concentration of atrazine spreading to the bottom of the columns indicated risk of groundwater contamination. Overall, HYDRUS-1D successfully simulated the atrazine transport in soil columns.
Homogenization of 1D and 2D magnetoelastic lattices
Directory of Open Access Journals (Sweden)
Schaeffer Marshall
Full Text Available This paper investigates the equivalent in-plane mechanical properties of one dimensional (1D and two dimensional (2D, periodic magneto-elastic lattices. A lumped parameter model describes the lattices using magnetic dipole moments in combination with axial and torsional springs. The homogenization procedure is applied to systems linearized about stable configurations, which are identified by minimizing potential energy. Simple algebraic expressions are derived for the properties of 1D structures. Results for 1D lattices show that a variety of stiffness changes are possible through reconfiguration, and that magnetization can either stiffen or soften a structure. Results for 2D hexagonal and re-entrant lattices show that both reconfigurations and magnetization have drastic effects on the mechanical properties of lattice structures. Lattices can be stiffened or softened and the Poisson's ratio can be tuned. Furthermore for certain hexagonal lattices the sign of Poisson's ratio can change by varying the lattice magnetization. In some cases presented, analytical and numerically estimated equivalent properties are validated through numerical simulations that also illustrate the unique characteristics of the investigated configurations.
Energy Technology Data Exchange (ETDEWEB)
We present a new hybrid Monte Carlo method for 1-D equilibrium diffusion problems in which the radiation field coexists with matter in local thermodynamic equilibrium. This method, the Equilibrium Discrete Diffusion Monte Carlo (EqDDMC) method, combines Monte Carlo particles with spatially discrete diffusion solutions. We verify the EqDDMC method with computational results from three slab problems. The EqDDMC method represents an incremental step toward applying this hybrid methodology to non-equilibrium diffusion, where it could be simultaneously coupled to Monte Carlo transport.
The Cosmological Mass Function with 1D Gravity
Monaco, P; Monaco, Pierluigi; Murante, Giuseppe
The cosmological mass function problem is analyzed in full detail in the case of 1D gravity, with analytical, semi-analytical and numerical techniques. The extended Press & Schechter theory is improved by detailing the relation between smoothing radius and mass of the objects. This is done by introducing in the formalism the concept of a growth curve for the objects. The predictions of the extended Press & Schechter theory are compared to large N-body simulations of flat expanding 1D universes with scale-free power spectra of primordial perturbations. The collapsed objects in the simulations are located with a clump-finding algorithm designed to find regions that have undergone orbit crossing or that are in the multi-stream regime (these are different as an effect of the finite size of the multi-stream regions). It is found that the semi-analytical mass function theory, which has no free parameters, is able to recover the properties of collapsed objects both statistically and object by object. In part...
Diamond-based 1-D imaging arrays
Energy Technology Data Exchange (ETDEWEB)
Lansley, S.P.; Williams, O.A.; Ye, H. [Electronic and Electrical Engineering, University College London, Torrington Place, London WC1E 7JE (United Kingdom); Rizvi, N.; Whitfield, M.D.; Jackman, R.B. [Exitech Limited, Hanborough Park, Long Hanborough, Oxford OX8 8LH (United Kingdom); McKeag, R.D. [Centronic Ltd., Centronic House, King Henry' s Drive, New Addington, Croydon CR9 OBG (United Kingdom)
Diamond has shown great promise for the fabrication of high sensitivity, low dark current, fast and visible-blind deep UV photodetectors. In addition to careful choice of substrate material, defect passivation treatments applied to the diamond after growth have been found to considerably enhance the detector characteristics achieved. In this paper we report on the first purposefully designed 1-D CVD diamond imaging array for the detection of nanosecond 193 nm excimer laser pulses using this approach. It is shown to perform extremely well, giving less than 2% pixel-to-pixel variation in signal response, and is fast enough to avoid any sign of charge build up during prolonged operation. (Abstract Copyright [2002], Wiley Periodicals, Inc.)
User's manual of the REFLA-1D/MODE4 reflood thermo-hydrodynamic analysis code
International Nuclear Information System (INIS)
REFLA-1D/MODE4 code has been developed by incorporating local power effect model and fuel temperature profile effect model into REFLA-1D/MODE3 code. This code can calculate the temperature transient of local rod by considering radial power profile effect in core and simulate the thermal characteristics of the nuclear fuel rod. This manual describes the outline of incorporated models, modification of the code with incorporating models and provides application information required to utilize the code. (author)
Morphodynamics and sediment tracers in 1-D (MAST-1D): 1-D sediment transport that includes exchange with an off-channel sediment reservoir
Lauer, J. Wesley; Viparelli, Enrica; Piégay, Hervé
Bed material transported in geomorphically active gravel bed rivers often has a local source at nearby eroding banks and ends up sequestered in bars not far downstream. However, most 1-D numerical models for gravel transport assume that gravel originates from and deposits on the channel bed. In this paper, we present a 1-D framework for simulating morphodynamic evolution of bed elevation and size distribution in a gravel-bed river that actively exchanges sediment with its floodplain, which is represented as an off-channel sediment reservoir. The model is based on the idea that sediment enters the channel at eroding banks whose elevation depends on total floodplain sediment storage and on the average elevation of the floodplain relative to the channel bed. Lateral erosion of these banks occurs at a specified rate that can represent either net channel migration or channel widening. Transfer of material out of the channel depends on a typical bar thickness and a specified lateral exchange rate due either to net channel migration or narrowing. The model is implemented using an object oriented framework that allows users to explore relationships between bank supply, bed structure, and lateral change rates. It is applied to a ∼50-km reach of the Ain River, France, that experienced significant reduction in sediment supply due to dam construction during the 20th century. Results are strongly sensitive to lateral exchange rates, showing that in this reach, the supply of sand and gravel at eroding banks and the sequestration of gravel in point bars can have strong influence on overall reach-scale sediment budgets.
Fleury, Leesa M
If the axion exists and if the initial axion field value is uncorrelated at causally disconnected points, then it should be possible to predict the efficiency of cosmological axion production, relating the axionic dark matter density to the axion mass. The main obstacle to making this prediction is correctly treating the axion string cores. We develop a new algorithm for treating the axionic string cores correctly in 2+1 dimensions. When the axionic string cores are given their full physical string tension, axion production is about twice as efficient as in previous simulations. We argue that the string network in 2+1 dimensions should behave very differently than in 3+1 dimensions, so this result cannot be simply carried over to the physical case. We outline how to extend our method to 3+1D axion string dynamics.
Analysis list: Nr1d2 [Chip-atlas[Archive
Lifescience Database Archive (English)
Full Text Available Nr1d2 Liver + mm9 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Nr1d2.1.tsv... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Nr1d2.5.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/target/Nr1d2....10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Nr1d2.Liver.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/colo/Liver.gml ...
This technical report describes the new one-dimensional (1D) hydrodynamic and sediment transport model EFDC1D. This model that can be applied to stream networks. The model code and two sample data sets are included on the distribution CD. EFDC1D can simulate bi-directional unstea...
Phase structure of (2+1)d strongly coupled lattice gauge theories
Strouthos, C G
We study the chiral phase transition in (2+1)d strongly coupled U(N) lattice gauge theories with staggered fermions. We show with high precision simulations performed directly in the chiral limit that these models undergo a Berezinski-Kosterlitz-Thouless (BKT) transition. We also show that this universality class is unaffected even in the large N limit.
Quantized 1D- and 2D optical molasses: Laser cooling and spectrum of resonance fluorescene
International Nuclear Information System (INIS)
We present results for laser cooling of optical molasses and the spectrum of resonance fluorescene based on a fully quantum mechanical treatment of the atomic center-of-mass motion for 1D and 2D laser configurations. Our calculations based on recently developed wave function simulations of the quantum master equation for laser cooling
Development of a new 1D urban canopy model: coherences between surface parameterizations
BLOND, Nadège; Mauree, Dasaraden; Kohler, Manon; Clappier, Alain
A 1-D Canopy Interface Model (CIM) was developed in order to better simulate the effect of urban obstacles on the atmosphere in the boundary layer. The model solves the Navier-Stokes equations on a high-resolved gridded vertical column. The effect of the surface is simulated testing a set of theories and urban parameterizations. The final proposition guarantees its coherence with past theories in any atmospheric stability and terrain configuration. Obstacle characteristics are computed using...
Opto-digital image encryption by using Baker mapping and 1-D fractional Fourier transform
Liu, Zhengjun; Li, She; Liu, Wei; Liu, Shutian
We present an optical encryption method based on the Baker mapping in one-dimensional fractional Fourier transform (1D FrFT) domains. A thin cylinder lens is controlled by computer for implementing 1D FrFT at horizontal direction or vertical direction. The Baker mapping is introduced to scramble the amplitude distribution of complex function. The amplitude and phase of the output of encryption system are regarded as encrypted image and key. Numerical simulation has been performed for testing the validity of this encryption scheme.
Numerical Methods and Comparisons for 1D and Quasi 2D Streamer Propagation Models
Huang, Mengmin; Guan, Huizhe; Zeng, Rong
In this work, we propose four different strategies to simulate the one-dimensional (1D) and quasi two-dimensional (2D) model for streamer propagation. Each strategy involves of one numerical method for solving Poisson's equation and another method for solving continuity equations in the models, and a total variation diminishing three-stage Runge-Kutta method in temporal discretization. The numerical methods for Poisson's equation include finite volume method, discontinuous Galerkin methods, mixed finite element method and least-squared finite element method. The numerical method for continuity equations is chosen from the family of discontinuous Galerkin methods. The accuracy tests and comparisons show that all of these four strategies are suitable and competitive in streamer simulations from the aspects of accuracy and efficiency. By applying any strategy in real simulations, we can study the dynamics of streamer propagations and influences due to the change of parameters in both of 1D and quasi 2D models. T...
Institute of Scientific and Technical Information of China (English)
XU Zu-xin; YIN Hai-long
Some coupled 1D-2D hydrodynamic and water quality models depicting tidal water bodies with complex topography were presented. For the coupled models, finite element method was used to solve the governing equations so as to study tidal rivers with complex topography. Since the 1D and 2D models were coupled, the principle of model coupling was proposed to account appropriately for the factors of water level, flow and pollutant flux and the related dynamical behavior was simulated. Specifically the models were used to probe quantitative pollution contribution of receiving water from neighboring Jiangsu and Zhejiang Provinces to the pollution in the Huangpu River passing through Shanghai City. Numerical examples indicated that the developed coupled 1D-2D models are applicable in tidal river network region of Shanghai.
Interaction of environmental contaminants with zebrafish organic anion transporting polypeptide, Oatp1d1 (Slco1d1)
International Nuclear Information System (INIS)
Polyspecific transporters from the organic anion transporting polypeptide (OATP/Oatp) superfamily mediate the uptake of a wide range of compounds. In zebrafish, Oatp1d1 transports conjugated steroid hormones and cortisol. It is predominantly expressed in the liver, brain and testes. In this study we have characterized the transport of xenobiotics by the zebrafish Oatp1d1 transporter. We developed a novel assay for assessing Oatp1d1 interactors using the fluorescent probe Lucifer yellow and transient transfection in HEK293 cells. Our data showed that numerous environmental contaminants interact with zebrafish Oatp1d1. Oatp1d1 mediated the transport of diclofenac with very high affinity, followed by high affinity towards perfluorooctanesulfonic acid (PFOS), nonylphenol, gemfibrozil and 17α-ethinylestradiol; moderate affinity towards carbaryl, diazinon and caffeine; and low affinity towards metolachlor. Importantly, many environmental chemicals acted as strong inhibitors of Oatp1d1. A strong inhibition of Oatp1d1 transport activity was found by perfluorooctanoic acid (PFOA), chlorpyrifos-methyl, estrone (E1) and 17β-estradiol (E2), followed by moderate to low inhibition by diethyl phthalate, bisphenol A, 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4 tetrahydronapthalene and clofibrate. In this study we identified Oatp1d1 as a first Solute Carrier (SLC) transporter involved in the transport of a wide range of xenobiotics in fish. Considering that Oatps in zebrafish have not been characterized before, our work on zebrafish Oatp1d1 offers important new insights on the understanding of uptake processes of environmental contaminants, and contributes to the better characterization of zebrafish as a model species. - Highlights: • We optimized a novel assay for determination of Oatp1d1 interactors • Oatp1d1 is the first SLC characterized fish xenobiotic transporter • PFOS, nonylphenol, diclofenac, EE2, caffeine are high affinity Oatp1d1substrates • PFOA, chlorpyrifos
Interaction of environmental contaminants with zebrafish organic anion transporting polypeptide, Oatp1d1 (Slco1d1)
Energy Technology Data Exchange (ETDEWEB)
Popovic, Marta; Zaja, Roko [Laboratory for Molecular Ecotoxicology, Division for Marine and Environmental Research, Rudjer Boskovic Institute, Bijenicka 54, 10 000 Zagreb (Croatia); Fent, Karl [University of Applied Sciences Northwestern Switzerland, School of Life Sciences, Gründenstrasse 40, CH-4132 Muttenz (Switzerland); Swiss Federal Institute of Technology (ETH Zürich), Department of Environmental System Sciences, Institute of Biogeochemistry and Pollution Dynamics, CH-8092 Zürich (Switzerland); Smital, Tvrtko, E-mail: firstname.lastname@example.com [Laboratory for Molecular Ecotoxicology, Division for Marine and Environmental Research, Rudjer Boskovic Institute, Bijenicka 54, 10 000 Zagreb (Croatia)
Polyspecific transporters from the organic anion transporting polypeptide (OATP/Oatp) superfamily mediate the uptake of a wide range of compounds. In zebrafish, Oatp1d1 transports conjugated steroid hormones and cortisol. It is predominantly expressed in the liver, brain and testes. In this study we have characterized the transport of xenobiotics by the zebrafish Oatp1d1 transporter. We developed a novel assay for assessing Oatp1d1 interactors using the fluorescent probe Lucifer yellow and transient transfection in HEK293 cells. Our data showed that numerous environmental contaminants interact with zebrafish Oatp1d1. Oatp1d1 mediated the transport of diclofenac with very high affinity, followed by high affinity towards perfluorooctanesulfonic acid (PFOS), nonylphenol, gemfibrozil and 17α-ethinylestradiol; moderate affinity towards carbaryl, diazinon and caffeine; and low affinity towards metolachlor. Importantly, many environmental chemicals acted as strong inhibitors of Oatp1d1. A strong inhibition of Oatp1d1 transport activity was found by perfluorooctanoic acid (PFOA), chlorpyrifos-methyl, estrone (E1) and 17β-estradiol (E2), followed by moderate to low inhibition by diethyl phthalate, bisphenol A, 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4 tetrahydronapthalene and clofibrate. In this study we identified Oatp1d1 as a first Solute Carrier (SLC) transporter involved in the transport of a wide range of xenobiotics in fish. Considering that Oatps in zebrafish have not been characterized before, our work on zebrafish Oatp1d1 offers important new insights on the understanding of uptake processes of environmental contaminants, and contributes to the better characterization of zebrafish as a model species. - Highlights: • We optimized a novel assay for determination of Oatp1d1 interactors • Oatp1d1 is the first SLC characterized fish xenobiotic transporter • PFOS, nonylphenol, diclofenac, EE2, caffeine are high affinity Oatp1d1substrates • PFOA, chlorpyrifos
First Observation of a Upsilon(1D) State
Bonvicini, G; Dubrovin, M; Bornheim, A; Lipeles, E; Pappas, S P; Shapiro, A; Weinstein, A J; Briere, R A; Chen, G P; Ferguson, T; Tatishvili, G T; Vogel, H; Watkins, M E; Adam, N E; Alexander, J P; Berkelman, K; Boisvert, V; Cassel, D G; Duboscq, J E; Ecklund, K M; Ehrlich, R; Galik, R S; Gibbons, L; Gittelman, B; Gray, S W; Hartill, D L; Heltsley, B K; Hsu, L; Jones, C D; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Magerkurth, A; Mahlke-Krüger, H; Meyer, T O; Patterson, J R; Pedlar, T K; Peterson, D; Pivarski, J; Riley, D; Rosner, J L; Sadoff, A J; Schwarthoff, H; Shepherd, M R; Sun, W M; Thayer, J G; Urner, D; Wilksen, T; Weinberger, M; Athar, S B; Avery, P; Breva-Newell, L; Potlia, V; Stöck, H; Yelton, J; Eisenstein, B I; Gollin, G D; Karliner, I; Lowrey, N; Naik, P; Sedlack, C; Selen, M; Thaler, J J; Williams, J; Edwards, K W; Besson, D; Gao, K Y; Gong, D T; Kubota, Y; Li, S Z; Poling, R A; Scott, A W; Smith, A; Stepaniak, C J; Urheim, J; Metreveli, Z V; Seth, K K; Tomaradze, A G; Zweber, P; Ernst, J; Arms, K; Eckhart, E; Gan, K K; Gwon, C; Severini, H; Skubic, P L; Asner, D M; Dytman, S A; Mehrabyan, S S; Müller, J A; Nam, S; Savinov, V; Huang, G S; Miller, D H; Pavlunin, V; Sanghi, B; Shibata, E I; Shipsey, I P J; Adams, G S; Chasse, M; Cummings, J P; Danko, I; Napolitano, J; Cronin-Hennessy, D; Park, C S; Park, W; Thayer, J B; Thorndike, E H; Coan, T E; Gao, Y S; Liu, F; Stroynowski, R; Artuso, M; Boulahouache, C; Blusk, S; Butt, J; Dambasuren, E; Dorjkhaidav, O; Haynes, J; Menaa, N; Mountain, R; Muramatsu, H; Nandakumar, R; Redjimi, R; Sia, R; Skwarnicki, T; Stone, S; Wang, J C; Zhang, Kevin; Mahmood, A H; Csorna, S E
We present the first evidence for the production of Upsilon(1D) states in the four-photon cascade, Upsilon(3S)-->gamma chib(2P), chib(2P)-->gamma Upsilon(1D), Upsilon(1D)-->gamma chib(1P), chib(1P)-->gamma Upsilon(1S), followed by the Upsilon(1S) annihilation into e+e- or mu+mu-. The signal has a significance of 10.2 standard deviations. The measured product branching ratio for these five decays, (2.5+-0.5+-0.5)x10^(-5), is consistent with the theoretical estimates. The data are dominated by the production of one Upsilon(1D) state consistent with the J=2 assignment. Its mass is determined to be (10161.1+-0.6+-1.6) MeV, which is consistent with the predictions from potential models and lattice QCD calculations. We also searched for Upsilon(3S)-->gammachib(2P), chib(2P)-->gammaUpsilon(1D), followed by either Upsilon(1D)-->eta Upsilon(1S) or Upsilon(1D)-->pi+pi- Upsilon(1S). We find no evidence for such decays and set upper limits on the product branching ratios.
The Gain Properties of 1-D Active Photonic Crystal
Institute of Scientific and Technical Information of China (English)
The terminology 'ID frequency'(w ID) is proposed after analyzing the 1D active photonic crystal based on the transfer matrix method. The relationship between wID and the structure parameters of the photonic crystal is investigated.
Severe Hypertriglyceridemia in Glut1D on Ketogenic Diet.
Klepper, Joerg; Leiendecker, Baerbel; Heussinger, Nicole; Lausch, Ekkehart; Bosch, Friedrich
High-fat ketogenic diets are the only treatment available for Glut1 deficiency (Glut1D). Here, we describe an 8-year-old girl with classical Glut1D responsive to a 3:1 ketogenic diet and ethosuximide. After 3 years on the diet a gradual increase of blood lipids was followed by rapid, severe asymptomatic hypertriglyceridemia (1,910 mg/dL). Serum lipid apheresis was required to determine liver, renal, and pancreatic function. A combination of medium chain triglyceride-oil and a reduction of the ketogenic diet to 1:1 ratio normalized triglyceride levels within days but triggered severe myoclonic seizures requiring comedication with sultiam. Severe hypertriglyceridemia in children with Glut1D on ketogenic diets may be underdiagnosed and harmful. In contrast to congenital hypertriglyceridemias, children with Glut1D may be treated effectively by dietary adjustments alone. PMID:26902182
TBC1D24 genotype–phenotype correlation
Balestrini, Simona; Milh, Mathieu; Castiglioni, Claudia; Lüthy, Kevin; Finelli, Mattea J.; Verstreken, Patrik; Cardon, Aaron; Stražišar, Barbara Gnidovec; Holder, J. Lloyd; Lesca, Gaetan; Mancardi, Maria M.; Poulat, Anne L.; Repetto, Gabriela M.; Banka, Siddharth; Bilo, Leonilda; Birkeland, Laura E.; Bosch, Friedrich; Brockmann, Knut; Cross, J. Helen; Doummar, Diane; Félix, Temis M.; Giuliano, Fabienne; Hori, Mutsuki; Hüning, Irina; Kayserili, Hulia; Kini, Usha; Lees, Melissa M.; Meenakshi, Girish; Mewasingh, Leena; Pagnamenta, Alistair T.; Peluso, Silvio; Mey, Antje; Rice, Gregory M.; Rosenfeld, Jill A.; Taylor, Jenny C.; Troester, Matthew M.; Stanley, Christine M.; Ville, Dorothee; Walkiewicz, Magdalena; Falace, Antonio; Fassio, Anna; Lemke, Johannes R.; Biskup, Saskia; Tardif, Jessica; Ajeawung, Norbert F.; Tolun, Aslihan; Corbett, Mark; Gecz, Jozef; Afawi, Zaid; Howell, Katherine B.; Oliver, Karen L.; Berkovic, Samuel F.; Scheffer, Ingrid E.; de Falco, Fabrizio A.; Oliver, Peter L.; Striano, Pasquale; Zara, Federico
Objective: To evaluate the phenotypic spectrum associated with mutations in TBC1D24. Methods: We acquired new clinical, EEG, and neuroimaging data of 11 previously unreported and 37 published patients. TBC1D24 mutations, identified through various sequencing methods, can be found online (http://lovd.nl/TBC1D24). Results: Forty-eight patients were included (28 men, 20 women, average age 21 years) from 30 independent families. Eighteen patients (38%) had myoclonic epilepsies. The other patients carried diagnoses of focal (25%), multifocal (2%), generalized (4%), and unclassified epilepsy (6%), and early-onset epileptic encephalopathy (25%). Most patients had drug-resistant epilepsy. We detail EEG, neuroimaging, developmental, and cognitive features, treatment responsiveness, and physical examination. In silico evaluation revealed 7 different highly conserved motifs, with the most common pathogenic mutation located in the first. Neuronal outgrowth assays showed that some TBC1D24 mutations, associated with the most severe TBC1D24-associated disorders, are not necessarily the most disruptive to this gene function. Conclusions: TBC1D24-related epilepsy syndromes show marked phenotypic pleiotropy, with multisystem involvement and severity spectrum ranging from isolated deafness (not studied here), benign myoclonic epilepsy restricted to childhood with complete seizure control and normal intellect, to early-onset epileptic encephalopathy with severe developmental delay and early death. There is no distinct correlation with mutation type or location yet, but patterns are emerging. Given the phenotypic breadth observed, TBC1D24 mutation screening is indicated in a wide variety of epilepsies. A TBC1D24 consortium was formed to develop further research on this gene and its associated phenotypes. PMID:27281533
L(d1, d2,..., dt)-Number λ(Cn; d1, d2,...,dt) of Cycles
Institute of Scientific and Technical Information of China (English)
GAO Zhen Bin; ZHANG Xiao Dong
An L(d1,d2,...,dt)-labeling of a graph G is a function f from its vertex set V(G) to the set {0, 1,..., k} for some positive integer k such that {f(x) - f(y)| ≥ di, if the distance between vertices x and y in G is equal to i for i = 1,2,...,t. The L(d1,d2,...,dt)-number λ(G;d1,d2,... ,dt) of G is the smallest integer number k such that G has an L(d1,d2,... ,dt)labeling with max{f(x)|x ∈ V(G)} = k. In this paper, we obtain the exact values for λ(Cn; 2, 2,1) and λ(Cn; 3, 2, 1), and present lower and upper bounds for λ(Cn; 2,..., 2,1,..., 1)
Characterisation and improvement of j(O1D) filter radiometers
Bohn, Birger; Heard, Dwayne E.; Mihalopoulos, Nikolaos; Plass-Dülmer, Christian; Schmitt, Rainer; Whalley, Lisa K.
Atmospheric O3 → O(1D) photolysis frequencies j(O1D) are crucial parameters for atmospheric photochemistry because of their importance for primary OH formation. Filter radiometers have been used for many years for in situ field measurements of j(O1D). Typically the relationship between the output of the instruments and j(O1D) is non-linear because of changes in the shape of the solar spectrum dependent on solar zenith angles and total ozone columns. These non-linearities can be compensated for by a correction method based on laboratory measurements of the spectral sensitivity of the filter radiometer and simulated solar actinic flux density spectra. Although this correction is routinely applied, the results of a previous field comparison study of several filter radiometers revealed that some corrections were inadequate. In this work the spectral characterisations of seven instruments were revised, and the correction procedures were updated and harmonised considering recent recommendations of absorption cross sections and quantum yields of the photolysis process O3 → O(1D). Previous inconsistencies were largely removed using these procedures. In addition, optical interference filters were replaced to improve the spectral properties of the instruments. Successive determinations of spectral sensitivities and field comparisons of the modified instruments with a spectroradiometer reference confirmed the improved performance. Overall, filter radiometers remain a low-maintenance alternative of spectroradiometers for accurate measurements of j(O1D) provided their spectral properties are known and potential drifts in sensitivities are monitored by regular calibrations with standard lamps or reference instruments.
Complex Langevin Dynamics in 1+1d QCD at Non-Zero Densities
Schmalzbauer, Sebastian
We present our results obtained from gauge cooled complex Langevin simulations in 1+1d QCD at non-zero densities in the strong coupling regime with unrooted staggered fermions. For small quark masses there are regions of the chemical potential where this method fails to reproduce correct results. In these parameter ranges we studied the effect of different gauge cooling schemes on the distributions of the fermion determinant as well as of observables.
Prediction of car cabin environment by means of 1D and 3D cabin model
Jícha M.; Pokorný J.; Fišer J.
Thermal comfort and also reduction of energy requirements of air-conditioning system in vehicle cabins are currently very intensively investigated and up-to-date issues. The article deals with two approaches of modelling of car cabin environment; the first model was created in simulation language Modelica (typical 1D approach without cabin geometry) and the second one was created in specialized software Theseus-FE (3D approach with cabin geometry). Performance and capabilities of this t...
1D-3D Hybrid Modelling - From Multi-Compartment Models to Full Resolution Models in Space and Time
Directory of Open Access Journals (Sweden)
Stephan eGrein
Full Text Available Investigation of cellular and network dynamics in the brain by means of modeling & simulation has evolved into a highly interdisciplinary field, that uses sophisticated modeling & simulation approaches to understand distinct areas of brain function. Depending on the underlying complexity, these models vary in level of detail to cope with the attached computational cost. Hence for large network simulations, single neurons are typically reduced to time-dependent signal processors, dismissing spatial aspects of the cells. For single cell or small-world networks, general purpose simulators allow for space and time-dependent simulations of electrical signal processing, based on the cable equation theory. An emerging field in Computational Neuroscience encompasses a new level of detail by incorporating the 3D morphology of cells and organelles into 3D space and time-dependent simulations. Every approach has its advantages and limitations, such as computational cost, integrated and methods-spanning simulation approaches, depending on the network size could establish new ways to investigate the brain. We present a hybrid simulation approach, that makes use of reduced 1D-models using e.g. the NEURON which couples to fully resolved models for simulating cellular and sub-cellular dynamics, including the detailed 3D-morphology of neurons and organelles. To couple 1D- & 3D-simulations, we present a geometry and membrane potential mapping framework, with which graph-based morphologies, e.g. in swc-/hoc-format, are mapped to full surface and volume representations of the neuron; membrane potential data from 1D-simulations are used as boundary conditions for full 3D simulations. Thus, established models and data, based on general purpose 1D-simulators, can be directly coupled to the emerging field of fully resolved highly detailed 3D-modeling approaches. The new framework is applied to investigate electrically active neurons and their intracellular spatio
1D nanocrystals with precisely controlled dimensions, compositions, and architectures
Pang, Xinchang; He, Yanjie; Jung, Jaehan; Lin, Zhiqun
The ability to synthesize a diverse spectrum of one-dimensional (1D) nanocrystals presents an enticing prospect for exploring nanoscale size- and shape-dependent properties. Here we report a general strategy to craft a variety of plain nanorods, core-shell nanorods, and nanotubes with precisely controlled dimensions and compositions by capitalizing on functional bottlebrush-like block copolymers with well-defined structures and narrow molecular weight distributions as nanoreactors. These cylindrical unimolecular nanoreactors enable a high degree of control over the size, shape, architecture, surface chemistry, and properties of 1D nanocrystals. We demonstrate the synthesis of metallic, ferroelectric, upconversion, semiconducting, and thermoelectric 1D nanocrystals, among others, as well as combinations thereof.
Iris Feature Extraction Method Based on 1D Gabor Filter
Institute of Scientific and Technical Information of China (English)
XU Guang-zhu; MA Yi-de; ZHANG Zai-feng
The normalized iris image was divided into eight sub-bands, and every column of each sub-band was averaged by rows to generate eight 1D iris signals. Then the even symmetry item of 1D Gabor filter was used to describe local characteristic blocks in 1D iris signals, and the results were quantified by their polarities to generate iris codes. In order to estimate the performance of the presented method, an iris recognition platform was produced and the Hamming distance between two iris codes was computed to measure the dissimilarity of them. The experimental results in CASIA v1 0 and Bath iris image databases show that the proposed iris feature extraction algorithm has a promising potential in iris recognition.
Prediction of car cabin environment by means of 1D and 3D cabin model
Fišer, J.; Pokorný, J.; Jícha, M.
Thermal comfort and also reduction of energy requirements of air-conditioning system in vehicle cabins are currently very intensively investigated and up-to-date issues. The article deals with two approaches of modelling of car cabin environment; the first model was created in simulation language Modelica (typical 1D approach without cabin geometry) and the second one was created in specialized software Theseus-FE (3D approach with cabin geometry). Performance and capabilities of this tools are demonstrated on the example of the car cabin and the results from simulations are compared with the results from the real car cabin climate chamber measurements.
Prediction of car cabin environment by means of 1D and 3D cabin model
Directory of Open Access Journals (Sweden)
Jícha M.
Full Text Available Thermal comfort and also reduction of energy requirements of air-conditioning system in vehicle cabins are currently very intensively investigated and up-to-date issues. The article deals with two approaches of modelling of car cabin environment; the first model was created in simulation language Modelica (typical 1D approach without cabin geometry and the second one was created in specialized software Theseus-FE (3D approach with cabin geometry. Performance and capabilities of this tools are demonstrated on the example of the car cabin and the results from simulations are compared with the results from the real car cabin climate chamber measurements.
Ngada, N M
The complexity and cost of building and running high-power electrical systems make the use of simulations unavoidable. The simulations available today provide great understanding about how systems really operate. This paper helps the reader to gain an insight into simulation in the field of power converters for particle accelerators. Starting with the definition and basic principles of simulation, two simulation types, as well as their leading tools, are presented: analog and numerical simulations. Some practical applications of each simulation type are also considered. The final conclusion then summarizes the main important items to keep in mind before opting for a simulation tool or before performing a simulation.
Nonreciprocity of edge modes in 1D magnonic crystal
International Nuclear Information System (INIS)
Spin waves propagation in 1D magnonic crystals is investigated theoretically. Mathematical model based on plane wave expansion method is applied to different types of magnonic crystals, namely bi-component magnonic crystal with symmetric/asymmetric boundaries and ferromagnetic film with periodically corrugated top surface. It is shown that edge modes in magnonic crystals may exhibit nonreciprocal behaviour at much lower frequencies than in homogeneous films. - Highlights: • Magnetostatic surface spin waves in 1D magnonic crystals were studied theoretically. • Mathematical model is based on plane wave method. • Mathematical model was applied to different types of magnonic crystals. • Stop band formation and nonreciprocity were obtained
Quantum electrodynamics with 1D arti cial atoms
DEFF Research Database (Denmark)
Javadi, Alisa
A 1D atom, a single quantum emitter coupled to a single optical mode, exhibits rich quantum electrodynamic (QED) e_ects and is thought to be the key ingredient for many applications in quantuminformation processing. Single quantum dots (QD) in photonic-crystal waveguides (PCW) constitute a robust...... as expected from the theory. The value of g(2)(0) is around 1.08. The results con_rm the observation of an on-chip giant optical nonlinearity and the 1D atom behavior. Another direction in this thesis has been to investigate the e_ect of Anderson localization on the electrodynamics of QDs in PCWs. A large...
1D antiferromagnetism in spin‐alternating bimetallic chains
Coronado Miralles, Eugenio; Sapiña Navarro, Fernando; Drillon, M.; De Jongh, L.J.
The magnetic and thermal properties of the ordered bimetallic chain CoNi(EDTA)⋅6H2O in the very low‐temperature range are reported. The magnetic behavior does not exhibit the characteristic features of 1D ferrimagnets, but a continuous decrease of χmT towards zero at absolute zero. This 1D antiferromagnetic behavior results from an accidental compensation between the moments located at the two sublattices. This behavior, as well as the specific‐heat results, are modeled on the basis of an Isi...
Nanoscale stabilization of zintl compounds: 1D ionic Li-P double helix confined inside a carbon nanotube.
Ivanov, Alexander S; Kar, Tapas; Boldyrev, Alexander I
One-dimensional (1D) ionic nanowires are extremely rare materials due to the difficulty in stabilizing 1D chains of ions under ambient conditions. We demonstrate here a theoretical prediction of a novel hybrid material, a nanotube encapsulated 1D ionic lithium monophosphide (LiP) chain, featuring a unique double-helix structure, which is very unusual in inorganic chemistry. This nanocomposite has been investigated with density functional theory, including molecular dynamics simulations and electronic structure calculations. We find that the formation of the LiP double-helical nanowire is facilitated by strong interactions between LiP and CNTs resulting in a charge transfer. This work suggests that nanostructured confinement may be used to stabilize other polyphosphide 1D chains, thus opening new ways to study the chemistry of zintl compounds at the nanoscale.
Institute of Scientific and Technical Information of China (English)
ZHOU Yi-lin; TANG Hong-wu; LIU Xiao-hua
An efficient and accurate solution algorithm was proposed for 1-D unsteady flow problems widely existing in hydraulic engineering. Based on the split-characteristic finite element method, the numerical model with the Saint-Venant equations of 1-D unsteady flows was established. The assembled finite element equations were solved with the tri-diagonal matrix algorithm. In the semi-implicit and explicit scheme, the critical time step of the method was dependent on the space step and flow velocity, not on the wave celerity. The method was used to eliminate the restriction due to the wave celerity for the computational analysis of unsteady open-channel flows. The model was verified by the experimental data and theoretical solution and also applied to the simulation of the flow in practical river networks. It shows that the numerical method has high efficiency and accuracy and can be used to simulate 1-D steady flows, and unsteady flows with shock waves or flood waves. Compared with other numerical methods, the algorithm of this method is simpler with higher accuracy, less dissipation, higher computation efficiency and less computer storage.
Modelling activities of experimental facilities related to advanced reactors. Considerations on 1D/3D issues
International Nuclear Information System (INIS)
The state of art of modelling activities related to integral experimental facilities of advanced passive reactors show to date important open items. The main advantage of using 1D plant codes is the capability of simulating the full interaction between components traditionally correctly modelled (condensers, heat exchangers, pipes and vessels) and other components for which codes are not 100% suitable (pools and containments). Polytechnical University of Catalonia (UPC) and Polytechnical University of Valencia (UPV) cooperated with other European research organizations in the 'Technology Enhancement for Passive Safety Systems' (TEPSS) project, within the European Fourth Framework Programme. It was a task of both Universities to supply analytical support of PANDA tests. The paper deals with the 1D/3D discussion in the framework of modelling activities related to integral passive facilities like PANDA. It starts choosing reference tests among those corresponding to our participation in TEPSS project. The discrepancies observed in a 1D simulation of the selected tests will be shown and analyzed. An evaluation of how the 3D version can lead to a better agreement with data will be included. Disadvantages of 3D codes will be shown too. Combining the use of different codes, and considering analyst criteria, will make possible to establish suitable recommendations from both engineering and scientific point of view. (author)
Nonclassical Particle Transport in the 1-D Diffusive Limit
Vasques, Richard; Krycki, Kai
This paper provides numerical results that demonstrate the validity of the nonclassical diffusion approximation to the nonclassical transport equation in certain 1-D diffusive systems. This result provides a more solid foundation in which to improve this theory for relevant nuclear applications.
Scattering approach to classical quasi-1D transport
Kogan, Eugene
General dynamical transport of classical particles in disordered quasi-1D samples is viewed in the framework of scattering approach. Simple equation for the transfer-matrix is obtained within this unified picture. In the case of diffusive transport the solution of this equation exactly coincides with the solution of diffusion equation.
Lifescience Database Archive (English)
Full Text Available 1D8U イネ Rice Oryza sativa L. Non-Symbiotic Hemoglobin 1 Name=Hb1; Synonyms=Glb1a; O...ryza Sativa Molecule: Non-Symbiotic Hemoglobin; Chain: A, B; Engineered: Yes Oxygen Storage/Transport M.Harg
Bessel Series in the Space H1(D)%H1(D)空间的Bessel级数
Institute of Scientific and Technical Information of China (English)
An identity concerning the partial sums of Bessel series and power series for H1(D) functions is given.Based on it,many of precise extimates about the deviation of the partial sums of Bessel series can be obtained.%本文给出关于H1(D)空间中函数的Bessel级数的部分和用幂级数的部分和表示的一个恒等式.基于它,可以得到Bessel级数部分和偏差的诸多精确估计.
A 1D model for the description of mixing-controlled reacting diesel sprays
Energy Technology Data Exchange (ETDEWEB)
Desantesa, J.M.; Pastor, J.V.; Garcia-Oliver, J.M.; Pastor, J.M. [CMT - Motores Termicos, Universidad Politecnica de Valencia, Camino de Vera s/n, 46022, Valencia (Spain)
The paper reports an investigation on the transient evolution of diesel flames in terms of fuel-air mixing, spray penetration and combustion rate. A one-dimensional (1D) spray model, which was previously validated for inert diesel sprays, is extended to reacting conditions. The main assumptions of the model are the mixing-controlled hypothesis and the validity of self-similarity for conservative properties. Validation is achieved by comparing model predictions with both CFD gas jet simulations and experimental diesel spray measurements. The 1D model provides valuable insight into the evolution of the flow within the spray (momentum and mass fluxes, tip penetration, etc.) when shifting from inert to reacting conditions. Results show that the transient diesel flame evolution is mainly governed by two combustion-induced effects, namely the reduction in local density and the increase in flame radial width. (author)
1D-3D hybrid modeling-from multi-compartment models to full resolution models in space and time.
Grein, Stephan; Stepniewski, Martin; Reiter, Sebastian; Knodel, Markus M; Queisser, Gillian
Investigation of cellular and network dynamics in the brain by means of modeling and simulation has evolved into a highly interdisciplinary field, that uses sophisticated modeling and simulation approaches to understand distinct areas of brain function. Depending on the underlying complexity, these models vary in their level of detail, in order to cope with the attached computational cost. Hence for large network simulations, single neurons are typically reduced to time-dependent signal processors, dismissing the spatial aspect of each cell. For single cell or networks with relatively small numbers of neurons, general purpose simulators allow for space and time-dependent simulations of electrical signal processing, based on the cable equation theory. An emerging field in Computational Neuroscience encompasses a new level of detail by incorporating the full three-dimensional morphology of cells and organelles into three-dimensional, space and time-dependent, simulations. While every approach has its advantages and limitations, such as computational cost, integrated and methods-spanning simulation approaches, depending on the network size could establish new ways to investigate the brain. In this paper we present a hybrid simulation approach, that makes use of reduced 1D-models using e.g., the NEURON simulator-which couples to fully resolved models for simulating cellular and sub-cellular dynamics, including the detailed three-dimensional morphology of neurons and organelles. In order to couple 1D- and 3D-simulations, we present a geometry-, membrane potential- and intracellular concentration mapping framework, with which graph- based morphologies, e.g., in the swc- or hoc-format, are mapped to full surface and volume representations of the neuron and computational data from 1D-simulations can be used as boundary conditions for full 3D simulations and vice versa. Thus, established models and data, based on general purpose 1D-simulators, can be directly coupled to the
Developing 1D nanostructure arrays for future nanophotonics
Directory of Open Access Journals (Sweden)
Cooke DG
Full Text Available AbstractThere is intense and growing interest in one-dimensional (1-D nanostructures from the perspective of their synthesis and unique properties, especially with respect to their excellent optical response and an ability to form heterostructures. This review discusses alternative approaches to preparation and organization of such structures, and their potential properties. In particular, molecular-scale printing is highlighted as a method for creating organized pre-cursor structure for locating nanowires, as well as vapor–liquid–solid (VLS templated growth using nano-channel alumina (NCA, and deposition of 1-D structures with glancing angle deposition (GLAD. As regards novel optical properties, we discuss as an example, finite size photonic crystal cavity structures formed from such nanostructure arrays possessing highQand small mode volume, and being ideal for developing future nanolasers.
1D Josephson quantum interference grids: diffraction patterns and dynamics
Lucci, M.; Badoni, D.; Corato, V.; Merlo, V.; Ottaviani, I.; Salina, G.; Cirillo, M.; Ustinov, A. V.; Winkler, D.
We investigate the magnetic response of transmission lines with embedded Josephson junctions and thus generating a 1D underdamped array. The measured multi-junction interference patterns are compared with the theoretical predictions for Josephson supercurrent modulations when an external magnetic field couples both to the inter-junction loops and to the junctions themselves. The results provide a striking example of the analogy between Josephson phase modulation and 1D optical diffraction grid. The Fiske resonances in the current-voltage characteristics with voltage spacing {Φ0}≤ft(\\frac{{\\bar{c}}}{2L}\\right) , where L is the total physical length of the array, {Φ0} the magnetic flux quantum and \\bar{c} the speed of light in the transmission line, demonstrate that the discrete line supports stable dynamic patterns generated by the ac Josephson effect interacting with the cavity modes of the line.
Phase diagram of a bulk 1d lattice Coulomb gas
Démery, V.; Monsarrat, R.; Dean, D. S.; Podgornik, R.
The exact solution, via transfer matrix, of the simple one-dimensional lattice Coulomb gas (1d LCG) model can reproduce peculiar features of ionic liquid capacitors, such as overscreening, layering, and camel- and bell-shaped capacitance curves. Using the same transfer matrix method, we now compute the bulk properties of the 1d LCG in the constant voltage ensemble. We unveil a phase diagram with rich structure exhibiting low-density disordered and high-density ordered phases, separated by a first-order phase transition at low temperature; the solid state at full packing can be ordered or not, depending on the temperature. This phase diagram, which is strikingly similar to its three-dimensional counterpart, also sheds light on the behaviour of the confined system.
New D1-D5-P geometries from string amplitudes
Giusto, Stefano; Turton, David
We derive the long range supergravity fields sourced by a D1-D5-P bound state from disk amplitudes for massless closed string emission. We suggest that since the parameter controlling the string perturbation expansion for this calculation decreases with distance from the bound state, the resulting asymptotic fields are valid even in the regime of parameters in which there is a classical black hole solution with the same charges. The supergravity fields differ from the black hole solution by multipole moments and are more general than those contained within known classes of solutions in the literature, whilst still preserving four supersymmetries. Our results support the conjecture that the black hole solution should be interpreted as a coarse-grained description rather than an exact description of the gravitational field sourced by D1-D5-P bound states in this regime of parameters.
D1-D5-P microstates at the cap
Giusto, Stefano; Mathur, Samir D; Turton, David
The geometries describing D1-D5-P bound states in string theory have three regions: flat asymptotics, an anti-de Sitter throat, and a 'cap' region at the bottom of the throat. We identify the CFT description of a known class of supersymmetric D1-D5-P microstate geometries which describe degrees of freedom in the cap region. The class includes both regular solutions and solutions with conical defects, and generalizes configurations with known CFT descriptions: a parameter related to spectral flow in the CFT is generalized from integer to fractional values. We provide strong evidence for this identification by comparing the massless scalar excitation spectrum between gravity and CFT and finding exact agreement.
Quantitative 1D saturation profiles on chalk by NMR
DEFF Research Database (Denmark)
Olsen, Dan; Topp, Simon; Stensgaard, Anders;
Quantitative one-dimensional saturation profiles showing the distribution of water and oil in chalk core samples are calculated from NMR measurements utilizing a 1D CSI spectroscopy pulse sequence. Saturation profiles may be acquired under conditions of fluid flow through the sample. Results reveal...... that strong saturation gradients exist in chalk core samples after core floods, due to capillary effects. The method is useful in analysis of corefloods, e.g., for determination of capillary pressure functions...
Blind Detection of Severely Blurred 1D Barcode
Dridi, Noura; Delignon, Yves; Sawaya, Wadih; Septier, François
In this paper, we present a joint blind channel estimation and symbol detection for decoding a blurred and noisy 1D barcode captured image. From an information transmission point of view, we show that the channel impulse response, the noise power and the symbols can be efficiently estimated by taking into account the signal structure such as the cyclostationary property of the hidden Markov process to estimate. Based on the Expectation-Maximisation method, we show that the new algorithm offer...
A study of slow light in 1D photonic crystals
Yudistira, D.; Hoekstra, H.J.W.M.; Hammer, M; Marpaung, D.A.I.
Slow light (SL) states corresponding to wavelength regions near the bandgap edge of grating structure are known to show strong field enhancement. Such states may be excited efficiently by well-optimised adiabatic transitions in such structures, e.g., by slowly turning on the modulation depth. To study adiabatic excitations, a detailed research in 1D is performed to obtain insight into the relation between the device parameters and properties like enhancement and modal reflection. The results ...
Theory of slow light excitation in 1D photonic crystals
Yudistira, D.; Marpaung, D.A.I.; Handoyo, H.P.; Hoekstra, H.J.W.M.; Hammer, M; Tjia, M.O.; Iskandar, A.A.
Slow light (SL) states corresponding to wavelength regions near the bandgap edge of grated structures are known to show strong eld enhancement. Such states may be excited efciently by well-optimised adiabatic transitions in grating structures, e.g., by slowly turning on the modulation depth. To study adiabatic excitations, a detailed investigation in 1D is performed to obtain insight into the relation between the device parameters and properties like eld enhancement and modal reection. The re...
Polaron in a quasi 1D cylindrical quantum wire
Directory of Open Access Journals (Sweden)
Full Text Available Polaron states in a quasi 1D cylindrical quantum wire with a parabolic confinement potential are investigated applying the Feynman variational principle. The effect of the wire radius on the polaron ground state energy level, the mass and the Fröhlich electron-phonon-coupling constant are obtained for the case of a quasi 1D cylindrical quantum wire. The effect of anisotropy of the structure on the polaron ground state energy level and the mass are also investigated. It is observed that as the wire radius tends to zero, the polaron mass and energy diverge logarithmically. The polaron mass and energy differ from the canonical strong-coupling behavior by the Fröhlich electron-phonon coupling constant and the radius of the quasi 1D cylindrical quantum wire that are expressed through a logarithmic function. Moreover, it is observed that the polaron energy and mass for strong coupling for the case of the quasi 1D cylindrical quantum wire are greater than those for bulk crystals. It is also observed that the anisotropy of the structure considerably affects both the polaron ground state energy level and the mass. It is found that as the radius of the cylindrical wire reduces, the regimes of the weak and intermediate coupling polaron shorten while the region of the strong coupling polaron broadens and extends into those of the weak and intermediate ones. Analytic expressions for the polaron ground state energy level and mass are derived for the case of strong coupling polarons.
Constructing 3D interaction maps from 1D epigenomes.
Zhu, Yun; Chen, Zhao; Zhang, Kai; Wang, Mengchi; Medovoy, David; Whitaker, John W; Ding, Bo; Li, Nan; Zheng, Lina; Wang, Wei
The human genome is tightly packaged into chromatin whose functional output depends on both one-dimensional (1D) local chromatin states and three-dimensional (3D) genome organization. Currently, chromatin modifications and 3D genome organization are measured by distinct assays. An emerging question is whether it is possible to deduce 3D interactions by integrative analysis of 1D epigenomic data and associate 3D contacts to functionality of the interacting loci. Here we present EpiTensor, an algorithm to identify 3D spatial associations within topologically associating domains (TADs) from 1D maps of histone modifications, chromatin accessibility and RNA-seq. We demonstrate that active promoter-promoter, promoter-enhancer and enhancer-enhancer associations identified by EpiTensor are highly concordant with those detected by Hi-C, ChIA-PET and eQTL analyses at 200 bp resolution. Moreover, EpiTensor has identified a set of interaction hotspots, characterized by higher chromatin and transcriptional activity as well as enriched TF and ncRNA binding across diverse cell types, which may be critical for stabilizing the local 3D interactions. PMID:26960733
Domain walls and instantons in N=1, d=4 supergravity
Huebscher, M; Ortin, T
We study the supersymmetric sources of (multi-) domain-wall and (multi-) instanton solutions of generic N=1, d=4 supergravities, that is: the worldvolume effective actions for said supersymmetric topological defects. The domain-wall solutions naturally couple to the two 3-forms recently found as part of the N=1, d=4 tensor hierarchy (i.e. they have two charges in general) and their tension is the absolute value of the superpotential section L. The introduction of sources (we study sources with finite and vanishing thickness) is equivalent to the introduction of local coupling constants and results in dramatic changes of the solutions. Our results call for a democratic reformulation of N=1,d=4 supergravity in which coupling constants are, off-shell, scalar fields. The effective actions for the instantons are always proportional to the coordinate orthogonal to the twist-free embedding of the null-geodesic (in the Wick-rotated scalar manifold) describing the instanton. We show their supersymmetry and find the as...
Development of 1D Liner Compression Code for IDL
Shimazu, Akihisa; Slough, John; Pancotti, Anthony
A 1D liner compression code is developed to model liner implosion dynamics in the Inductively Driven Liner Experiment (IDL) where FRC plasmoid is compressed via inductively-driven metal liners. The driver circuit, magnetic field, joule heating, and liner dynamics calculations are performed at each time step in sequence to couple these effects in the code. To obtain more realistic magnetic field results for a given drive coil geometry, 2D and 3D effects are incorporated into the 1D field calculation through use of correction factor table lookup approach. Commercial low-frequency electromagnetic fields solver, ANSYS Maxwell 3D, is used to solve the magnetic field profile for static liner condition at various liner radius in order to derive correction factors for the 1D field calculation in the code. The liner dynamics results from the code is verified to be in good agreement with the results from commercial explicit dynamics solver, ANSYS Explicit Dynamics, and previous liner experiment. The developed code is used to optimize the capacitor bank and driver coil design for better energy transfer and coupling. FRC gain calculations are also performed using the liner compression data from the code for the conceptual design of the reactor sized system for fusion energy gains.
Coupling of Nod1D and HOTCHANNEL: static case
International Nuclear Information System (INIS)
In this work the joining of the programs Nod1D and HOTCHANNEL, developed in the National Polytechnic Institute (IPN) and in the Electrical Research Institute (IIE) respectively is described. The first one allows to study the neutronic of a nuclear reactor and the second one allows to carry out the analysis of hot channel of a Boiling Water Reactor (BWR). Nod1 D is a program that it solves by nodal methods type finite element those diffusion equations in multigroup, and it is the static part of Nod Kin that it solves the diffusion equation in their time dependent part. For another side HOTCHANNEL is based on a mathematical model constituted by four conservation equations (two of mass conservation, one of motion quantity and one of energy), which are solved applying one discretization in implicit finite differences. Both programs have been verified in independent form using diverse test problems. In this work the modifications that were necessary to carry out to both for obtaining a coupled program that it provides the axial distribution of the neutron flux, the power, the burnup and the void fraction, among others parameters as much as neutronic as thermal hydraulics are described. Those are also mentioned limitations, advantages and disadvantages of the final product to which has been designated Nod1 D-HotChn. Diverse results for the Cycle 1 of the Laguna Verde Unit 1 reactor of the Nucleo electric central comparing them with those obtained directly with the CoreMasterPresto code are provided. (Author)
MARG1D: One dimensional outer region matching data code
International Nuclear Information System (INIS)
A code MARG1D has been developed which computes outer region matching data of the one dimensional Newcomb equation. Matching data play an important role in the resistive (and non ideal) Magneto-hydrodynamic (MHD) stability analysis in a tokamak plasma. The MARG1D code computes matching data by using the boundary value method or by the eigenvalue method. Variational principles are derived for the problems to be solved and a finite element method is applied. Except for the case of marginal stability, the eigenvalue method is equivalent to the boundary value method. However, the eigenvalue method has the several advantages: it is a new method of ideal MHD stability analysis for which the marginally stable state can be identified, and it guarantees numerical stability in computing matching data close to marginal stability. We perform detailed numerical experiments for a model equation with analytical solutions and for the Newcomb equation in the m=1 mode theory. Numerical experiments show that MARG1D code gives the matching data with numerical stability and high accuracy. (author)
Examining Prebiotic Chemistry Using O(^1D) Insertion Reactions
Hays, Brian M.; Laas, Jacob C.; Weaver, Susanna L. Widicus
Aminomethanol, methanediol, and methoxymethanol are all prebiotic molecules expected to form via photo-driven grain surface chemistry in the interstellar medium (ISM). These molecules are expected to be precursors for larger, biologically-relevant molecules in the ISM such as sugars and amino acids. These three molecules have not yet been detected in the ISM because of the lack of available rotational spectra. A high resolution (sub)millimeter spectrometer coupled to a molecular source is being used to study these molecules using O(^1D) insertion reactions. The O(^1D) chemistry is initiated using an excimer laser, and the products of the insertion reactions are adiabatically cooled using a supersonic expansion. Experimental parameters are being optimized by examination of methanol formed from O(^1D) insertion into methane. Theoretical studies of the structure and reaction energies for aminomethanol, methanediol, and methoxymethanol have been conducted to guide the laboratory studies once the methanol experiment has been optimized. The results of the calculations and initial experimental results will be presented.
Molecular characterization of zebrafish Oatp1d1 (Slco1d1), a novel organic anion-transporting polypeptide.
Popovic, Marta; Zaja, Roko; Fent, Karl; Smital, Tvrtko
The organic anion-transporting polypeptide (OATP/Oatp) superfamily includes a group of polyspecific transporters that mediate transport of large amphipathic, mostly anionic molecules across cell membranes of eukaryotes. OATPs/Oatps are involved in the disposition and elimination of numerous physiological and foreign compounds. However, in non-mammalian species, the functional properties of Oatps remain unknown. We aimed to elucidate the role of Oatp1d1 in zebrafish to gain insights into the functional and structural evolution of the OATP1/Oatp1 superfamily. We show that diversification of the OATP1/Oatp1 family occurs after the emergence of jawed fish and that the OATP1A/Oatp1a and OATP1B/Oatp1b subfamilies appeared at the root of tetrapods. The Oatp1d subfamily emerged in teleosts and is absent in tetrapods. The zebrafish Oatp1d1 is similar to mammalian OATP1A/Oatp1a and OATP1B/Oatp1b members, with the main physiological role in transport and balance of steroid hormones. Oatp1d1 activity is dependent upon pH gradient, which could indicate bicarbonate exchange as a mode of transport. Our analysis of evolutionary conservation and structural properties revealed that (i) His-79 in intracellular loop 3 is conserved within OATP1/Oatp1 family and is crucial for the transport activity; (ii) N-glycosylation impacts membrane targeting and is conserved within the OATP1/Oatp1 family with Asn-122, Asn-133, Asn-499, and Asn-512 residues involved; (iii) the evolutionarily conserved cholesterol recognition interaction amino acid consensus motif is important for membrane localization; and (iv) Oatp1d1 is present in dimeric and possibly oligomeric form in the cell membrane. In conclusion, we describe the first detailed characterization of a new Oatp transporter in zebrafish, offering important insights into the functional evolution of the OATP1/Oatp1 family and the physiological role of Oatp1d1.
Neutronic analysis of the 1D and 1E banks reflux detection system
Energy Technology Data Exchange (ETDEWEB)
Blanchard, A.
Two H Canyon neutron monitoring systems for early detection of postulated abnormal reflux conditions in the Second Uranium Cycle 1E and 1D Mixer-Settle Banks have been designed and built. Monte Carlo neutron transport simulations using the general purpose, general geometry, n-particle MCNP code have been performed to model expected response of the monitoring systems to varying conditions.The confirmatory studies documented herein conclude that the 1E and 1D neutron monitoring systems are able to achieve adequate neutron count rates for various neutron source and detector configurations, thereby eliminating excessive integration count time. Neutron count rate sensitivity studies are also performed. Conversely, the transport studies concluded that the neutron count rates are statistically insensitive to nitric acid content in the aqueous region and to the transition region length. These studies conclude that the 1E and 1D neutron monitoring systems are able to predict the postulated reflux conditions for all examined perturbations in the neutron source and detector configurations. In the cases examined, the relative change in the neutron count rates due to postulated transitions from normal {sup 235}U concentration levels to reflux levels remain satisfactory detectable.
Optimizing the Emitter Layer for Higher Efficiency Solar Cell Based SiGe Using AMPS1D
Boukais Meriem; B. Dennai; A. Ould-Abbas
The thin-film SiGe is considered as promising candidate to meet the outstanding need for photovoltaic applications with enhanced adsorption characteristics and improved conversion efficiency [1-6]. In this paper, we simulated a solar cell type SiGe using AMPS1D (Analysis of Microelectronic and photonic structure) developed at Pennsylvania State University, to analyze emitter layer (thickness, doping) and we studied their influence on the photovoltaic solar cell. The simulation result shows th...
Analysis on characteristics of 1-D apodized and chirped photonic crystals containing negative refractive materials
Institute of Scientific and Technical Information of China (English)
TONG Kai; CUI Wei-wei; XU Xiao-hui; LI Zhi-quan
Using transfer matrix method, the optical transmission properties of 1-D photonic crystals composed partially of negativerefraction media are analyzed. The transmission spectra of periodic photonic crystal, chirped photonic crystal and apodizedphotonic crystal are numerically simulated respectively. By contrast with optical transmission properties of ordinary photo-nic crystals made of positive refraction media, the transmission spectra of apodized photonic crystal become unregular, theBragg flat-headed area recurs but the peak of transmission does not change significantly. Futhermore, the band gap rangeof chirped photonic crystal diminishes gradually.
Superfluid behavior of quasi-1D p-H$_2$ inside carbon nanotube
Rossi, Maurizio; Ancilotto, Francesco
We perform ab-initio Quantum Monte Carlo simulations of para-hydrogen (pH$_2$) at $T=0$ K confined in carbon nanotubes (CNT) of different radii. The radial density profiles show a strong layering of the pH$_2$ molecules which grow, with increasing number of molecules, in solid concentric cylindrical shells and eventually a central column. The central column can be considered an effective one-dimensional (1D) fluid whose properties are well captured by the Tomonaga-Luttinger liquid theory. The...
Coupling of Nod1D and HOTCHANNEL: static case; Acoplamiento de Nod1D y HOTCHANNEL: caso estatico
Energy Technology Data Exchange (ETDEWEB)
Gomez T, A.M. [IPN-ESFM, 07738 Mexico D.F. (Mexico); Ovando C, R. [IIE-Gcia. de Energia Nuclear, Cuernavaca, Morelos (Mexico)]. e-mail: email@example.com
In this work the joining of the programs Nod1D and HOTCHANNEL, developed in the National Polytechnic Institute (IPN) and in the Electrical Research Institute (IIE) respectively is described. The first one allows to study the neutronic of a nuclear reactor and the second one allows to carry out the analysis of hot channel of a Boiling Water Reactor (BWR). Nod1 D is a program that it solves by nodal methods type finite element those diffusion equations in multigroup, and it is the static part of Nod Kin that it solves the diffusion equation in their time dependent part. For another side HOTCHANNEL is based on a mathematical model constituted by four conservation equations (two of mass conservation, one of motion quantity and one of energy), which are solved applying one discretization in implicit finite differences. Both programs have been verified in independent form using diverse test problems. In this work the modifications that were necessary to carry out to both for obtaining a coupled program that it provides the axial distribution of the neutron flux, the power, the burnup and the void fraction, among others parameters as much as neutronic as thermal hydraulics are described. Those are also mentioned limitations, advantages and disadvantages of the final product to which has been designated Nod1 D-HotChn. Diverse results for the Cycle 1 of the Laguna Verde Unit 1 reactor of the Nucleo electric central comparing them with those obtained directly with the CoreMasterPresto code are provided. (Author)
Extended-Range Ultrarefractive 1D Photonic Crystal Prisms
Ting, David Z.
A proposal has been made to exploit the special wavelength-dispersive characteristics of devices of the type described in One-Dimensional Photonic Crystal Superprisms (NPO-30232) NASA Tech Briefs, Vol. 29, No. 4 (April 2005), page 10a. A photonic crystal is an optical component that has a periodic structure comprising two dielectric materials with high dielectric contrast (e.g., a semiconductor and air), with geometrical feature sizes comparable to or smaller than light wavelengths of interest. Experimental superprisms have been realized as photonic crystals having three-dimensional (3D) structures comprising regions of amorphous Si alternating with regions of SiO2, fabricated in a complex process that included sputtering. A photonic crystal of the type to be exploited according to the present proposal is said to be one-dimensional (1D) because its contrasting dielectric materials would be stacked in parallel planar layers; in other words, there would be spatial periodicity in one dimension only. The processes of designing and fabricating 1D photonic crystal superprisms would be simpler and, hence, would cost less than do those for 3D photonic crystal superprisms. As in 3D structures, 1D photonic crystals may be used in applications such as wavelength-division multiplexing. In the extended-range configuration, it is also suitable for spectrometry applications. As an engineered structure or artificially engineered material, a photonic crystal can exhibit optical properties not commonly found in natural substances. Prior research had revealed several classes of photonic crystal structures for which the propagation of electromagnetic radiation is forbidden in certain frequency ranges, denoted photonic bandgaps. It had also been found that in narrow frequency bands just outside the photonic bandgaps, the angular wavelength dispersion of electromagnetic waves propagating in photonic crystal superprisms is much stronger than is the angular wavelength dispersion obtained
Coherent thermal conductance of 1-D photonic crystals
Tschikin, Maria; Ben-Abdallah, Philippe; Biehs, Svend-Age
We present an exact calculation of coherent thermal conductance in 1-D multilayer photonic crystals using the S-matrix method. In particular, we study the thermal conductance in a bilayer structure of Si/vacuum or Al2O3/vacuum slabs by means of the exact radiative heat flux expression. Based on the results obtained for the Al2O3/vacuum structure we show by comparison with previous works that the material losses and (localized) surface modes supported by the inner layers play a fundamental role and cannot be omitted in the definition of thermal conductance. Our results could have significant implications in the conception of efficient thermal barriers.
Spatial coherence of polaritons in a 1D channel
Energy Technology Data Exchange (ETDEWEB)
Savenko, I. G., E-mail: email@example.com [Russian Academy of Sciences, Academic University, Research and Education Center of Nanotechnologies (Russian Federation); Iorsh, I. V. [National Research University of Information Technologies, Mechanics and Optics (Russian Federation); Kaliteevski, M. A. [Russian Academy of Sciences, Academic University, Research and Education Center of Nanotechnologies (Russian Federation); Shelykh, I. A. [University of Iceland, Science Institute (Iceland)
We analyze time evolution of spatial coherence of a polariton ensemble in a quantum wire (1D channel) under constant uniform resonant pumping. Using the theoretical approach based on the Lindblad equation for a one-particle density matrix, which takes into account the polariton-phonon and excitonexciton interactions, we study the behavior of the first-order coherence function g{sup 1} for various pump intensities and temperatures in the range of 1-20 K. Bistability and hysteresis in the dependence of the first-order coherence function on the pump intensity is demonstrated.
Phthalocyanine based 1D nanowires for device applications
Saini, Rajan; Mahajan, Aman; Bedi, R. K.
1D nanowires (NWs) of Cu (II) 1,4,8,11,15,18,22,25-octabutoxy-29H,31H-Phthalocyanine (CuPc(OBu)8) molecule have been grown on different substrates by cost effective solution processing technique. The density of NWs is found to be strongly dependent on the concentration of solution. The possible formation mechanism of these structures is π-π interaction between phthalocyanine molecules. The improved conductivity of these NWs as compared to spin coated film indicates their potential for molecular device applications.
Restrained Dark $U(1)_d$ at Low Energies
Correia, F C
We investigate a spontaneously broken $U(1)_d$ gauge symmetry with a muon-specific dark Higgs. Our first goal is to verify how the presence of a new dark Higgs, $\\phi$, and a dark gauge boson, $V$, can simultaneously face the anomalies from the muon magnetic moment and the proton charge radius. Secondly, by assuming that $V$ must decay to an electron-positron pair, we explore the corresponding parameter space determined with the low energy constraints coming from $ K \\to \\mu X$, electron $(g-2)_e$, $K \\to \\mu \
Breakdown of 1D water wires inside Charged Carbon Nanotubes
Pant, Shashank
Using Molecular Dynamics approach we investigated the structure, dynamics of water confined inside pristine and charged 6,6 carbon nanotubes (CNTs). This study reports the breakdown of 1D water wires and the emergence of triangular faced water on incorporating charges in 6,6 CNTs. Incorporation of charges results in high potential barriers to the flipping of water molecules due to the formation of a large number of hydrogen bonds. The PMF analyses show the presence of ~2 kcal/mol barrier for the movement of water inside pristine CNT and almost negligible barrier in charged CNTs.
A Godunov method for Lagrangian hydrodynamics in 1D
Energy Technology Data Exchange (ETDEWEB)
Crowley, W.P.
For transient problems involving strong shocks, the artificial viscosity method has been the standard in numerical hydrodynamics for many years. An alternative approach was suggested by Godunov and it is gaining acceptance. We consider a Godunov method for 1D Lagrangian calculations and show that in the case of a strong shock moving through a nonuniform mesh the Godunov solution is superior to the artificial viscosity solution. For uniform mesh shock problems in spherical geometry the two methods give comparable results. 4 refs., 9 figs.
Study of 1D Strange Charmed Meson Family Using HQET
Directory of Open Access Journals (Sweden)
Pallavi Gupta
Full Text Available Recently LHCb predicted spin 1 and spin 3 states Ds1⁎(2860 and Ds3⁎(2860 which are studied through their strong decays and are assigned to fit the 13D1 and 13D3 states in the charm spectroscopy. In this paper, using the heavy quark effective theory, we state that assigning Ds1⁎(2860 as the mixing of 13D1-23S1 states is rather a better justification to its observed experimental values than a pure state. We study its decay modes variation with hadronic coupling constant gxh and the mixing angle θ. We appoint spin 3 state Ds3⁎(2860 as the missing 1D 3-JP state and also study its decay channel behavior with coupling constant gyh. To appreciate the above results, we check the variation of decay modes for their spin partners states, that is, 1D2 and 1D2′, with their masses and strong coupling constant, that is, gxh and gyh. Our calculation using HQET approach gives mixing angle of the 13D1-23S1 state for Ds1⁎(2860 to lie in the range (-1.6 radians ≤θ≤-1.2 radians. Our calculation for coupling constant values gives gxh to lie within value range of 0.17–0.20 and gyh to be 0.40. We expect from experiments to observe this mixing angle to verify our results.
A Framework for Low-Communication 1-D FFT
Directory of Open Access Journals (Sweden)
Ping Tak Peter Tang
Full Text Available In high-performance computing on distributed-memory systems, communication often represents a significant part of the overall execution time. The relative cost of communication will certainly continue to rise as compute-density growth follows the current technology and industry trends. Design of lower-communication alternatives to fundamental computational algorithms has become an important field of research. For distributed 1-D FFT, communication cost has hitherto remained high as all industry-standard implementations perform three all-to-all internode data exchanges (also called global transposes. These communication steps indeed dominate execution time. In this paper, we present a mathematical framework from which many single-all-to-all and easy-to-implement 1-D FFT algorithms can be derived. For large-scale problems, our implementation can be twice as fast as leading FFT libraries on state-of-the-art computer clusters. Moreover, our framework allows tradeoff between accuracy and performance, further boosting performance if reduced accuracy is acceptable.
A simple quasi-1D model of Fibonacci anyons
Aasen, David; Mong, Roger; Clarke, David; Alicea, Jason; Fendley, Paul
There exists various ways of understanding the topological properties of Ising anyons--from simple free-fermion toy models to formal topological quantum field theory. For other types of anyons simple toy models rarely exist; their properties have to be obtained using formal self-consistency relations. We explore a family of gapped 1D local bosonic models that in a certain limit become trivial to solve and provide an intuitive picture for Fibonacci anyons. One can interpret this model as a quasi-1D wire that forms the building block of a 2D topological phase with Fibonacci anyons. With this interpretation all topological properties of the Fibonacci anyons become manifest including ground state degeneracy and braid relations. We conjecture that the structure of the model is protected by an emergent symmetry analogous to fermion parity. 1) NSF Grant DMR-1341822 2) Institute for Quantum Information and Matter, an NSF physics frontier center with support from the Moore Foundation. 3) NSERC-PGSD.
Hamming Distance and Data Compression of 1-D CA
Directory of Open Access Journals (Sweden)
Raied Salman
Full Text Available In this paper an application of von Neumann correct ion technique to the output string of some chaotic rules of 1-D Cellular Automata that are uns uitable for cryptographic pseudo random number generation due to their non uniform distribu tion of the binary elements is presented. The one dimensional (1-D Cellular Automata (CA Ru le space will be classified by the time run of Hamming Distance (HD. This has the advantage of determining the rules that have short cycle lengths and therefore deemed to be unsuitable for cryptographic pseudo random number generation. The data collected from evolution of ch aotic rules that have long cycles are subjected to the original von Neumann density corre ction scheme as well as a new generalized scheme presented in this paper and tested for stati stical testing fitness using Diehard battery of tests. Results show that significant improvement in the statistical tests are obtained when the output of a balanced chaotic rule are mutually excl usive ORed with the output of unbalanced chaotic rule that have undergone von Neumann densit y correction.
Transformation of 1-D Chiral-chained Titanium Phosphate to 2-D Layer Structure Through a 1-D Zigzag Chain
Institute of Scientific and Technical Information of China (English)
CHEN Chao; YANG Yu-lin; LI Wei-sheng; LIU Yun-ling; YI Zhuo; GUO Yang-hong; PANG Wen-qin
The transformation of titanium phosphate from 1-D chiral- chain(JTP-A) to 2-D layer(TP-J1) has been carefully investigated. Through a hydrolysis-condensation self-assembly pathway, the crystals of TP-J1 can be obtained from the JTP-A phase under hydrothermal conditions. An intermediate material with zigzag chain during the transformation was observed by XRD characterization. A hypothesis of the transformation mechanism is also described in this article. It is noteworthy that ethylenediamine plays an important role in the transformation.
Statistical investigation and thermal properties for a 1-D impact system with dissipation
Díaz I., Gabriel; Livorati, André L. P.; Leonel, Edson D.
The behavior of the average velocity, its deviation and average squared velocity are characterized using three techniques for a 1-D dissipative impact system. The system - a particle, or an ensemble of non-interacting particles, moving in a constant gravitation field and colliding with a varying platform - is described by a nonlinear mapping. The average squared velocity allows to describe the temperature for an ensemble of particles as a function of the parameters using: (i) straightforward numerical simulations; (ii) analytically from the dynamical equations; (iii) using the probability distribution function. Comparing analytical and numerical results for the three techniques, one can check the robustness of the developed formalism, where we are able to estimate numerical values for the statistical variables, without doing extensive numerical simulations. Also, extension to other dynamical systems is immediate, including time dependent billiards.
Simplified 1D modelling of the HGA test
International Nuclear Information System (INIS)
Document available in extended abstract form only. The HGA test is located in the Mont Terri Rock Laboratory (Switzerland). It consists of a horizontal borehole of 1.00 m of diameter and 13.00 m of length excavated in the ultra-low permeable Opalinus clay. During the tunnel drilling, the Opalinus clay near the tunnel wall was damaged, giving rise to an EDZ (Excavation Damaged Zone) around the tunnel. A steel liner was placed along the 6.00 m close to the tunnel mouth in order to guarantee the stability. The last 4.00 m at the tunnel end were backfilled with gravel. Along the remaining 3.00 m, an inflatable rubber packer of 1.00 m in diameter, was installed and inflated, thereby compressing the EDZ that was created during the tunnel excavation. The test section was filled with de-aired water and care was taken in order to eliminate the air from this tunnel section. Subsequently, a series of water and gas injection tests were carried out with varying mega-packer pressure, whereby water or gas was injected into the test section and, due to the very low permeability of the intact Opalinus clay, forced to flow back along the EDZ. In order to model the water and gas flow through the EDZ, we have followed a two-track approach. On the one hand, a 2D axisymmetric numerical model using code-bright has been made. On the other hand, a 1D analytical-numerical model has been developed and implemented in an Excel spreadsheet, whereby the field equations defined on a 1D geometrical domain are numerically solved using the finite element method. The 1D model has been used in order to calibrate the 2D axisymmetric model. Both the Opalinus clay and the EDZ will be considered to be porous media, with an incompressible solid phase (clay), an incompressible liquid phase (water and air) and a gas phase (water and air). The properties of the liquid phase will be assumed to be independent of the concentration of dissolved air and the gas phase will be assumed to be a mixture of dry air and
Data of evolutionary structure change: 1D6QA-2G4QA [Confc[Archive
Lifescience Database Archive (English)
Full Text Available 1D6QA-2G4QA 1D6Q 2G4Q A A KVFERCELARTLKRLGMDGYRGISLANWMCLAKWESGYN...GRCELAAAMKRHGLDNYRGYSLGNWVCAAKFESNFNTQATNRNTD-GSTDYGILQINSRWWCNDGRTPGSRNLCNIPCSALLSSDITASVNCAKKIVSDGNGMNAWVAWRNRCKGTDVQA...bID> A 2G4QA NRNTD-GS...> 1D6Q A 1D6QA
DEFF Research Database (Denmark)
Gould, Derek A; Chalmers, Nicholas; Johnson, Sheena J;
Recognition of the many limitations of traditional apprenticeship training is driving new approaches to learning medical procedural skills. Among simulation technologies and methods available today, computer-based systems are topical and bring the benefits of automated, repeatable, and reliable...... performance assessments. Human factors research is central to simulator model development that is relevant to real-world imaging-guided interventional tasks and to the credentialing programs in which it would be used....
Identification of a T1D Susceptibility Gene
Directory of Open Access Journals (Sweden)
Grant Morahan
Full Text Available It is not known what causes type 1 diabetes (T1D, which affects over 1 million people in the U.S. alone. Each year, 30,000 young people in the U.S. develop this disease and depend on insulin injections thereafter. Because of the huge cost to the individual, the family, and to society in increased health care costs, it is important to find what makes these people susceptible. The disease process itself is clear: the individual's immune system — T lymphocytes in particular — attack and destroy the body's insulin-producing cells. But how and why this autoimmune process starts or proceeds unregulated is still not known.
Effective theory of Black Holes in the 1/D expansion
Emparan, Roberto; Suzuki, Ryotaku; Tanabe, Kentaro; Tanaka, Takahiro
The gravitational field of a black hole is strongly localized near its horizon when the number of dimensions D is very large. In this limit, we can effectively replace the black hole with a surface in a background geometry (eg Minkowski or Anti-deSitter space). The Einstein equations determine the effective equations that this 'black hole surface' (or membrane) must satisfy. We obtain them up to next-to-leading order in 1/D for static black holes of the Einstein-(A)dS theory. To leading order, and also to next order in Minkowski backgrounds, the equations of the effective theory are the same as soap-film equations, possibly up to a redshift factor. In particular, the Schwarzschild black hole is recovered as a spherical soap bubble. Less trivially, we find solutions for 'black droplets', ie black holes localized at the boundary of AdS, and for non-uniform black strings.
Microlens Masses from 1-D Parallaxes and Heliocentric Proper Motions
Gould, Andrew
One-dimensional (1-D) microlens parallaxes can be combined with heliocentric lens-source relative proper motion measurements to derive the lens mass and distance, as suggested by Ghosh et al. (2004). Here I present the first mathematical anlysis of this procedure, which I show can be represented as a quadratic equation. Hence, it is formally subject to a two-fold degeneracy. I show that this degeneracy can be broken in many cases using the relatively crude 2-D parallax information that is often available for microlensing events. I also develop an explicit formula for the region of parameter space where it is more difficult to break this degeneracy. Although no mass/distance measurements have yet been made using this technique, it is likely to become quite common over the next decade.
Phenomenological predictions of 3+1d anisotropic hydrodynamics
Nopoush, Mohammad; Ryblewski, Radoslaw
We make phenomenological predictions for particle spectra and elliptic flow in heavy-ion collisions using 3+1d anisotropic hydrodynamics (aHydro) including the effects of both shear and bulk viscosities. The dynamical equations necessary are derived by taking moments of the Boltzmann equation allowing for three distinct (diagonal) momentum-space anisotropy parameters. The formulation is based on relaxation-time approximation for the collisional kernel and a lattice-QCD-based equation of state. Evolving the system to late times, we calculate particle production using THERMINATOR 2, modified to account for an ellipsoidal distribution function. We obtain particle spectra for different particle species such as pions, kaons, and protons, and elliptic flow $v_2$ as a function of centrality, transverse momentum, and rapidity. In our model, we have four free parameters, i.e. freeze-out temperature, initial central energy density, initial momentum-space anisotropies, and shear viscosity to entropy density ratio. Using...
Programming for seismogram 1-D generation, considering the attenuation and dispersing effects; Programa para gerar sismograma 1-D, considerando os efeitos da atenuacao e dispersao
Energy Technology Data Exchange (ETDEWEB)
Rodrigues, Bruno de O.; Oliveira, Sergio A.M. de [Universidade Estadual do Norte Fluminense (UENF), Macae, RJ (Brazil). Lab. de Engenharia e Exploracao do Petroleo (LENEP)
For a processing and an interpretation of correct seismic data, it is necessary to recognize and to know as the factors act that influence in the propagation of the seismic waves, as the attenuation and the dispersion, constituting in the biggest practical impediment for the use of seismic for targets the big depths, limiting the resolution of the method. However these phenomena little are taken in consideration in the analysis of the data, thus the necessity of its bigger agreement, because if attenuation and dispersion they confuse the application of the seismic, if convenient understood and measures, can be valuable sources of information about the constitution of the rocks. Therefore, in this work the effect of the attenuation and dispersion in the data of reflection seismic had been simulated on a program, in Mat-Lab. Being able to generate 1-D seismograms, in the domain of the time, considering the normal incidence of plain wave in a package of plain, horizontal and isotropic layers, taking in account the physical attributes of the way, being able to simulate the effects of ghost and of multiples of free surface, if considering the source in the water. (author)
Computational Study and Analysis of Structural Imperfections in 1D and 2D Photonic Crystals
Energy Technology Data Exchange (ETDEWEB)
Maskaly, Karlene Rosera [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
increasing RMS roughness. Again, the homogenization approximation is able to predict these results. The problem of surface scratches on 1D photonic crystals is also addressed. Although the reflectivity decreases are lower in this study, up to a 15% change in reflectivity is observed in certain scratched photonic crystal structures. However, this reflectivity change can be significantly decreased by adding a low index protective coating to the surface of the photonic crystal. Again, application of homogenization theory to these structures confirms its predictive power for this type of imperfection as well. Additionally, the problem of a circular pores in 2D photonic crystals is investigated, showing that almost a 50% change in reflectivity can occur for some structures. Furthermore, this study reveals trends that are consistent with the 1D simulations: parameter changes that increase the absolute reflectivity of the photonic crystal will also increase its tolerance to structural imperfections. Finally, experimental reflectance spectra from roughened 1D photonic crystals are compared to the results predicted computationally in this thesis. Both the computed and experimental spectra correlate favorably, validating the findings presented herein.
Nested 1D-2D approach for urban surface flood modeling
Murla, Damian; Willems, Patrick
Floods in urban areas as a consequence of sewer capacity exceedance receive increased attention because of trends in urbanization (increased population density and impermeability of the surface) and climate change. Despite the strong recent developments in numerical modeling of water systems, urban surface flood modeling is still a major challenge. Whereas very advanced and accurate flood modeling systems are in place and operation by many river authorities in support of flood management along rivers, this is not yet the case in urban water management. Reasons include the small scale of the urban inundation processes, the need to have very high resolution topographical information available, and the huge computational demands. Urban drainage related inundation modeling requires a 1D full hydrodynamic model of the sewer network to be coupled with a 2D surface flood model. To reduce the computational times, 0D (flood cones), 1D/quasi-2D surface flood modeling approaches have been developed and applied in some case studies. In this research, a nested 1D/2D hydraulic model has been developed for an urban catchment at the city of Gent (Belgium), linking the underground sewer (minor system) with the overland surface (major system). For the overland surface flood modelling, comparison was made of 0D, 1D/quasi-2D and full 2D approaches. The approaches are advanced by considering nested 1D-2D approaches, including infiltration in the green city areas, and allowing the effects of surface storm water storage to be simulated. An optimal nested combination of three different mesh resolutions was identified; based on a compromise between precision and simulation time for further real-time flood forecasting, warning and control applications. Main streets as mesh zones together with buildings as void regions constitute one of these mesh resolution (3.75m2 - 15m2); they have been included since they channel most of the flood water from the manholes and they improve the accuracy of
Extended 1D Method for Coherent Synchrotron Radiation including Shielding
Sagan, David; Mayes, Christopher; Sae-Ueng, Udom
Coherent Synchrotron Radiation can severely limit the performance of accelerators designed for high brightness and short bunch length. Examples include light sources based on ERLs or FELs, and bunch compressors for linear colliders. In order to better simulate Coherent Synchrotron Radiation, the established 1-dimensional formalism is extended to work at lower energies, at shorter bunch lengths, and for an arbitrary configuration of multiple bends. Wide vacuum chambers are simulated by means of vertical image charges. This formalism has been implemented in the general beam dynamics code "Bmad" and its results are here compared to analytical approximations, to numerical solutions of the Maxwell equations, and to the simulation code "elegant".
Development of the CELVA-1D code to evaluate the safety of an air-ventilation system during postulated fire and explosion in the reprocessing plant. Contract research
Energy Technology Data Exchange (ETDEWEB)
Nishio, Gunji; Watanabe, Kouji [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Kouno, Kouji; Yamazaki, Noboru; Mukaide, Shigeo; Yoshioka, Itsuo
The CELVA-1D computer code was developed to evaluate the confinement of radioactive materials during postulated fire and explosion in a cell of nuclear fuel reprocessing plants. The CELVA-1D code calculates a response of temperature, pressure, flow velocity of fluid in an air-ventilation system of the plants by one-dimensional thermofluid analysis and calculates an ability to confine radioactive aerosol particles by transport, deposition, and HEPA filtration. The mathematical models in CELVA-1D were verified by comparison of the calculation with the result of JAERI`s demonstration tests simulating hypothetical fire and explosion accidents in the cell. (author)
Ross, Sheldon
Ross's Simulation, Fourth Edition introduces aspiring and practicing actuaries, engineers, computer scientists and others to the practical aspects of constructing computerized simulation studies to analyze and interpret real phenomena. Readers learn to apply results of these analyses to problems in a wide variety of fields to obtain effective, accurate solutions and make predictions about future outcomes. This text explains how a computer can be used to generate random numbers, and how to use these random numbers to generate the behavior of a stochastic model over time. It presents the statist
Improving 1D Stellar Models with 3D Atmospheres
Mosumgaard, Jakob Rørsted; Weiss, Achim; Christensen-Dalsgaard, Jørgen; Trampedach, Regner
Stellar evolution codes play a major role in present-day astrophysics, yet they share common issues. In this work we seek to remedy some of those by the use of results from realistic and highly detailed 3D hydrodynamical simulations of stellar atmospheres. We have implemented a new temperature stratification extracted directly from the 3D simulations into the Garching Stellar Evolution Code to replace the simplified atmosphere normally used. Secondly, we have implemented the use of a variable mixing-length parameter, which changes as a function of the stellar surface gravity and temperature -- also derived from the 3D simulations. Furthermore, to make our models consistent, we have calculated new opacity tables to match the atmospheric simulations. Here, we present the modified code and initial results on stellar evolution using it.
Modelling hydrology of a single bioretention system with HYDRUS-1D.
Meng, Yingying; Wang, Huixiao; Chen, Jiangang; Zhang, Shuhan
A study was carried out on the effectiveness of bioretention systems to abate stormwater using computer simulation. The hydrologic performance was simulated for two bioretention cells using HYDRUS-1D, and the simulation results were verified by field data of nearly four years. Using the validated model, the optimization of design parameters of rainfall return period, filter media depth and type, and surface area was discussed. And the annual hydrologic performance of bioretention systems was further analyzed under the optimized parameters. The study reveals that bioretention systems with underdrains and impervious boundaries do have some detention capability, while their total water retention capability is extremely limited. Better detention capability is noted for smaller rainfall events, deeper filter media, and design storms with a return period smaller than 2 years, and a cost-effective filter media depth is recommended in bioretention design. Better hydrologic effectiveness is achieved with a higher hydraulic conductivity and ratio of the bioretention surface area to the catchment area, and filter media whose conductivity is between the conductivity of loamy sand and sandy loam, and a surface area of 10% of the catchment area is recommended. In the long-term simulation, both infiltration volume and evapotranspiration are critical for the total rainfall treatment in bioretention systems.
Nonclassical Particle Transport in 1-D Random Periodic Media
Vasques, Richard; Slaybaugh, Rachel N
We investigate the accuracy of the recently proposed nonclassical transport equation. This equation contains an extra independent variable compared to the classical transport equation (the path-length $s$), and models particle transport taking place in homogenized random media in which a particle's distance-to-collision is not exponentially distributed. To solve the nonclassical equation one needs to know the $s$-dependent ensemble-averaged total cross section, $\\Sigma_t(\\mu,s)$, or its corresponding path-length distribution function, $p(\\mu,s)$. We consider a 1-D spatially periodic system consisting of alternating solid and void layers, randomly placed in the $x$-axis. We obtain an analytical expression for $p(\\mu,s)$ and use this result to compute the corresponding $\\Sigma_t(\\mu,s)$. Then, we proceed to numerically solve the nonclassical equation for different test problems in rod geometry; that is, particles can move only in the directions $\\mu=\\pm 1$. To assess the accuracy of these solutions, we produce ...
Dynamics of fermionization for strongly interacting photons in 1D
Muth, Dominik; Schmidt, Bernd; Fleischhauer, Michael
When slow-light photons are confined to one spatial dimension with strong repulsive two-photon scattering they will fermionize, i.e. they will form the analog of a Lieb-Liniger gas in the Tonks limit [1]. We here analyze the dynamics of this process both for repulsive and attractive elastic two-photon scattering using exact numerical methods. We observe that the local two-body correlation attains a steady-state value after a short time, which is however substantially above the ground-state value of the Lieb-Liniger gas but is very close to the value in a high temperature state. This can be explained as a local thermalization to a temperature corresponding to the energy input by the sudden onset of interactions. Non-local two-particle correlations approach the steady-state on a longer time scale. In the case of attractive interactions, the non local correlations indicate a relaxation to a metastable steady-state, the super Tonks-Girardeau gas, recently seen for bosons in the experiment by Haller et al. [2]. [1] D. E. Chang, V. Gritsev, G. Morigi, V. Vuletic, M. D. Lukin, and E. A. Demler, Nature Physics 4, 884 (2008) [2] E. Haller, M. Gustavsson, M. J. Mark, J. G. Danzl, R. Hart, G. Pupillo, and H. C. Naegerl, Science 325, 1224 (2009)
Single molecule magnet behavior observed in a 1-D dysprosium chain with quasi-D5h symmetry.
Huang, Xing-Cai; Zhang, Ming; Wu, Dayu; Shao, Dong; Zhao, Xin-Hua; Huang, Wei; Wang, Xin-Yi
Two one-dimensional (1-D) chain complexes with pentagonal bipyramidal Dy(III) centers have been synthesized and magnetically characterized. Field-induced single molecule magnet behavior has been revealed in both compounds, which is still rarely reported in a lanthanide compound with a pentagonal bipyramidal coordination geometry. Their crystal field parameters and orientations of the magnetic easy axes were obtained from the simulation of the magnetic data and the electrostatic model calculation. PMID:26593051
Numerical Simulation of Oxygen-rich CNG Engine Based on 1D/3D Coupled Model%基于一维/三维模型耦合的富氧燃烧天然气发动机数值模拟
Institute of Scientific and Technical Information of China (English)
姜伟; 张玉银; 李世琰; 张勇; 张伟
以某1.0 L3缸汽油机为基础,利用 GT-Power与Converge建立了天然气发动机耦合仿真模型,并利用原机试验数据对模型进行了验证,研究了进气富氧与 EGR 对天然气发动机性能的影响特性,对利用进气富氧与EGR 改善天然气发动机的性能进行了探讨。结果表明,随进气氧气体积分数提高,天然气发动机平均有效压力显著提高,最大可提高22.8%(氧体积分数为28%时);同时缸内温度和 NOx 排放升高,排气与传热的能量损失增加,燃气消耗率略有升高。加入 EGR 可以降低富氧燃烧下天然气发动机燃气消耗率,随着 EGR 率增加,燃气消耗率主要呈先减小后增加趋势;且随进气氧浓度提高,各浓度下最低燃气消耗率对应的 EGR 率逐渐提高;NOx 排放随EGR 率增加而逐渐降低,在进气氧体积分数为23%,25%,27%,29%时,EGR 率分别为10%,15%,20%,25%即可将 NOx 排放降到原机水平;利用进气富氧与 EGR 可以有效地改善天然气发动机动力不足与 NOx 排放高的状况。%The coupled simulation model of CNG engine was built with GT-Power and Converge software based on a 1.0 L gasoline engine and was calibrated with test data of original engine.Then the influences of oxygen-rich intake and EGR on CNG engine perform-ance were researched and the performance improvements thereof were discussed.The results show that BMEP for CNG engine increases obviously with the increase of oxygen volume fraction and increases by 22.8% at most in 28% oxygen content.Moreover,the in-cylin-der temperature,NOx emission,the energy loss of exhaust and heat transfer all increase and BSFC slightly increases.The specific CNG consumption under the conditions of rich oxygen decreases by introducing EGR and shows the trend of first decrease and following in-crease with the increase of EGR rate.The corresponding EGR rate of the lowest CNG consumption
Synthesis of 1-D ZnO nanorods and polypyrrole/1-D ZnO nanocomposites for photocatalysis and gas sensor applications
Indian Academy of Sciences (India)
1-D ZnO nanorods and PPy/1-D ZnO nanocomposites were prepared by the surfactant-assisted precipitation and in situ polymerization method, respectively. The synthesized nanorods and nanocomposites were characterized by UV–Vis spectrophotometer, Fourier transform-infrared spectroscopy (FTIR), X-ray diffraction (XRD) and field emission scanning electron microscope (FE-SEM), which gave the evidence of 1-D ZnO nanorods, polymerization of pyrrole monomer and strong interaction between PPy and 1-D ZnO nanorods, respectively. Photocatalytic activity of 1-D ZnO nanorods was conducted by $3^3$ level full-factorial design to evaluate the effect of three independent process variables viz., dye concentration (crystal violet), catalyst concentration (1-D ZnO nanorods) and the reaction time on the preferred response: photodegradation efficiency (%). The PPy/1-D ZnO nanocompositeswere used for the sensing of NH$_3$, LPG, CO$_2$ and H$_2$S gases, respectively, at room temperature. It was observed that PPy/1-D ZnO nanocomposites with different 1-D ZnO nanorod weight ratios (15 and 25%) had better selectivity and sensitivity towards NH3 at room temperature.
A comparative study of 1D and 3D hemodynamics in patient-specific hepatic portal vein networks
Directory of Open Access Journals (Sweden)
Jonášová A.
Full Text Available The development of software for use in clinical practice is often associated with many requirements and restrictions set not only by the medical doctors, but also by the hospital's budget. To meet the requirement of reliable software, which is able to provide results within a short time period and with minimal computational demand, a certain measure of modelling simplification is usually inevitable. In case of blood flow simulations carried out in large vascular networks such as the one created by the hepatic portal vein, simplifications are made by necessity. The most often employed simplification includes the approach in the form of dimensional reduction, when the 3D model of a large vascular network is substituted with its 1D counterpart. In this context, a question naturally arises, how this reduction can affect the simulation accuracy and its outcome. In this paper, we try to answer this question by performing a quantitative comparison of 3D and 1D flow models in two patient-specific hepatic portal vein networks. The numerical simulations are carried out under average flow conditions and with the application of the three-element Windkessel model, which is able to approximate the downstream flow resistance of real hepatic tissue. The obtained results show that, although the 1D model can never truly substitute the 3D model, its easy implementation, time-saving model preparation and almost no demands on computer technology dominate as advantages over obvious but moderate modelling errors arising from the performed dimensional reduction.
Fluid friction and wall viscosity of the 1D blood flow model.
Wang, Xiao-Fei; Nishi, Shohei; Matsukawa, Mami; Ghigo, Arthur; Lagrée, Pierre-Yves; Fullana, Jose-Maria
We study the behavior of the pulse waves of water into a flexible tube for application to blood flow simulations. In pulse waves both fluid friction and wall viscosity are damping factors, and difficult to evaluate separately. In this paper, the coefficients of fluid friction and wall viscosity are estimated by fitting a nonlinear 1D flow model to experimental data. In the experimental setup, a distensible tube is connected to a piston pump at one end and closed at another end. The pressure and wall displacements are measured simultaneously. A good agreement between model predictions and experiments was achieved. For amplitude decrease, the effect of wall viscosity on the pulse wave has been shown as important as that of fluid viscosity. PMID:26862041
Initial Stage of the Microwave Ionization Wave Within a 1D Model
Semenov, V. E.; Rakova, E. I.; Glyavin, M. Yu.; Nusinovich, G. S.
The dynamics of the microwave breakdown in a gas is simulated numerically within a simple 1D model which takes into account such processes as the impact ionization of gas molecules, the attachment of electrons to neutral molecules, and plasma diffusion. Calculations are carried out for different spatial distributions of seed electrons with account for reflection of the incident electromagnetic wave from the plasma. The results reveal considerable dependence of the ionization wave evolution on the relation between the field frequency and gas pressure, as well as on the existence of extended rarefied halo of seed electrons. At relatively low gas pressures (or high field frequencies), the breakdown process is accompanied by the stationary ionization wave moving towards the incident electromagnetic wave. In the case of a high gas pressure (or a relatively low field frequency), the peculiarities of the breakdown are associated with the formation of repetitive jumps of the ionization front.
Fluid friction and wall viscosity of the 1D blood flow model
Wang, Xiao-Fei; Matsukawa, Mami; Ghigo, Arthur; Lagrée, Pierre-Yves; Fullana, Jose-Maria
We study the behavior of the pulse waves of water into a flexible tube for application to blood flow simulations. In pulse waves both fluid friction and wall viscosity are damping factors, and difficult to evaluate separately. In this paper, the coefficients of fluid friction and wall viscosity are estimated by fitting a nonlinear 1D flow model to experimental data. In the experimental setup, a distensible tube is connected to a piston pump at one end and closed at another end. The pressure and wall displacements are measured simultaneously. A good agreement between model predictions and experiments was achieved. For amplitude decrease, the effect of wall viscosity on the pulse wave has been shown as important as that of fluid viscosity.
Wavelength modulated SERS hot spot distribution in 1D nanostructures on metal film
Wang, Lili; Zeng, Xiping; Liu, Ting; Zhang, Xuemei; Wei, Hua; Huang, Yingzhou; Liu, Anping; Wang, Shuxia; Wen, Weijia
Surface plasmons confining strong electromagnetic fields near metal surfaces, well-known as hot spots, provide an extremely efficient platform for surface-enhanced Raman scattering (SERS). In this work, SERS spectra of probing molecules in a silver particle-wire 1D nanostructure on a thin gold film are investigated. The Raman features of SERS spectra collected at the particle-wire joints exhibit an obvious wavelength dependence phenomenon. This result is confirmed electromagnetic field simulation, revealing that hot spot distribution is sensitively influenced by the wavelength of incident light at the joints. Further studies indicate this wavelength dependence of hot spot distribution is immune to influence from the geometric shape of the particle or the angle between wire and particle, which improves fabrication tolerance. This technology may have promising applications in surface plasmon related fields, such as ultrasensors, solar energy and selective surface catalysis.
Survey of Multi-Material Closure Models in 1D Lagrangian Hydrodynamics
Energy Technology Data Exchange (ETDEWEB)
Maeng, Jungyeoul Brad [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hyde, David Andrew Bulloch [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Accurately treating the coupled sub-cell thermodynamics of computational cells containing multiple materials is an inevitable problem in hydrodynamics simulations, whether due to initial configurations or evolutions of the materials and computational mesh. When solving the hydrodynamics equations within a multi-material cell, we make the assumption of a single velocity field for the entire computational domain, which necessitates the addition of a closure model to attempt to resolve the behavior of the multi-material cells' constituents. In conjunction with a 1D Lagrangian hydrodynamics code, we present a variety of both the popular as well as more recently proposed multi-material closure models and survey their performances across a spectrum of examples. We consider standard verification tests as well as practical examples using combinations of fluid, solid, and composite constituents within multi-material mixtures. Our survey provides insights into the advantages and disadvantages of various multi-material closure models in different problem configurations.
Data of evolutionary structure change: 1D1SB-1QLJA [Confc[Archive
Lifescience Database Archive (English)
Full Text Available 1D1SB-1QLJA 1D1S 1QLJ B A GTAGKVIKCKAAVLWEQKQPFSIEEIEVAPPKTKEVRIK...EMTGNNVGYTFEVIGHLETMIDALASCHMNYGTSVVVGVPPSAKMLTYDPMLLFTGRTWKGCVFGGLKSRDDVPKLVTEFLAKKFDLDQL...ne>GLY CA 380 VAL CA 377 1QL...J A 1QLJA LKNDLSMPRGT
Data of evolutionary structure change: 1D3AB-1LLDA [Confc[Archive
Lifescience Database Archive (English)
Full Text Available 1D3AB-1LLDA 1D3A 1LLD B A -TKVSVVGAAGTVGAAAGYNIALRDIADEVVFVDIPDKE...PNAIYMLITNPVDIATHVAQKLTGLPENQIFGSGTNLDSARLRFLIAQQTGVNVKNVHAYIAGEHGDSEVPLWESATIGGVPMSDWTPLPGHDPLDADKREEIHQEVK... 1LLD A 1LLDA...> 1 1LLD A 1LLDA
Method of coupling 1-D unsaturated flow with 3-D saturated flow on large scale
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Yan ZHU
Full Text Available A coupled unsaturated-saturated water flow numerical model was developed. The water flow in the unsaturated zone is considered the one-dimensional vertical flow, which changes in the horizontal direction according to the groundwater table and the atmospheric boundary conditions. The groundwater flow is treated as the three-dimensional water flow. The recharge flux to groundwater from soil water is considered the bottom flux for the numerical simulation in the unsaturated zone, and the upper flux for the groundwater simulation. It connects and unites the two separated water flow systems. The soil water equation is solved based on the assumed groundwater table and the subsequent predicted recharge flux. Then, the groundwater equation is solved with the predicted recharge flux as the upper boundary condition. Iteration continues until the discrepancy between the assumed and calculated groundwater nodal heads have a certain accuracy. Illustrative examples with different water flow scenarios regarding the Dirichlet boundary condition, the Neumann boundary condition, the atmospheric boundary condition, and the source or sink term were calculated by the coupled model. The results are compared with those of other models, including Hydrus-1D, SWMS-2D, and FEFLOW, which demonstrate that the coupled model is effective and accurate and can significantly reduce the computational time for the large number of nodes in saturated-unsaturated water flow simulation.
Data of evolutionary structure change: 1D0GD-2RJLA [Confc[Archive
Lifescience Database Archive (English)
Full Text Available 1D0GD-2RJLA 1D0G 2RJL D A PQRVAAHITGTRGEKALGRKINSWESSRSGHSFLS-NLH...LRNGELVIHEKGFYYIYSQTYFRFQEEIKENTKNDKQMVQYIYKYTS-YPDPILLMKSARNSCWSKDAEYGLYSIYQGGIFELKENDRIFVSVTNEHLIDM-DHEASFFGAFLVG GD...KPRAHLTVVRQTPTQFPALHWEHEL--GLAFTKNRMNYTNKFLLIPESGDYFIYSQVTFRG--------MKPDSITVVITKVTDS...YPEPTQLLMGTKSVS-EVG-SNWFQPIYLGAMFSLQEGDKLMVNVSDISLVDYTKEDKTFFGAFLL- ...D0G D 1D0GD HSFLS-NLHLR
From nonfinite to finite 1D arrays of origami tiles.
Wu, Tsai Chin; Rahman, Masudur; Norton, Michael L
average solution structures for blocks is more readily achieved using computer models than using direct imaging methods. The development of scalable 1D-origami arrays composed of uniquely addressable components is a logical, if not necessary, step in the evolution of higher order fully addressable structures. Our research into the fabrication of arrays has led us to generate a listing of several important areas of future endeavor. Of high importance is the re-enforcement of the mechanical properties of the building blocks and the organization of multiple arrays on a surface of technological importance. While addressing this short list of barriers to progress will prove challenging, coherent development along each of these lines of inquiry will accelerate the appearance of commercial scale molecular manufacturing. PMID:24803094
Biot-JKD model: simulation of 1D transient poroelastic waves with fractional derivatives
Blanc, Emilie; Lombard, Bruno
A time-domain numerical modeling of Biot poroelastic waves is presented. The viscous dissipation occurring in the pores is described using the dynamic permeability model developed by Johnson-Koplik-Dashen (JKD). Some of the coefficients in the Biot-JKD model are proportional to the square root of the frequency: in the time-domain, these coefficients introduce order 1/2 shifted fractional derivatives involving a convolution product. Based on a diffusive representation, the convolution kernel is replaced by a finite number of memory variables that satisfy local-in-time ordinary differential equations. Thanks to the dispersion relation, the coefficients in the diffusive representation are obtained by performing an optimization procedure in the frequency range of interest. A splitting strategy is then applied numerically: the propagative part of Biot-JKD equations is discretized using a fourth-order ADER scheme on a Cartesian grid, whereas the diffusive part is solved exactly. Comparisons with analytical solution...
Linking 1D Evolutionary to 3D Hydrodynamical Simulations of Massive Stars
Cristini, Andréa; Hirschi, Raphael; Arnett, David; Georgy, Cyril; Viallet, Maxime
Stellar evolution models of massive stars are important for many areas of astrophysics, for example nucleosynthesis yields, supernova progenitor models and understanding physics under extreme conditions. Turbulence occurs in stars primarily due to nuclear burning at different mass coordinates within the star. The understanding and correct treatment of turbulence and turbulent mixing at convective boundaries in stellar models has been studied for decades but still lacks a definitive solution. This paper presents initial results of a study on convective boundary mixing (CBM) in massive stars. The 'stiffness' of a convective boundary can be quantified using the bulk Richardson number ($\\textrm{Ri}_B$), the ratio of the potential energy for restoration of the boundary to the kinetic energy of turbulent eddies. A 'stiff' boundary ($\\textrm{Ri}_B \\sim 10^4$) will suppress CBM, whereas in the opposite case a 'soft' boundary ($\\textrm{Ri}_B \\sim 10$) will be more susceptible to CBM. One of the key results obtained so...
1D Simulations for Microbial Enhanced Oil Recovery with Metabolite Partitioning
DEFF Research Database (Denmark)
Nielsen, Sidsel Marie; Shapiro, Alexander; Michelsen, Michael Locht;
We have developed a mathematical model describing the process of microbial enhanced oil recovery (MEOR). The one-dimensional isothermal model comprises displacement of oil bywater containing bacteria and substrate for their feeding. The bacterial products are both bacteria andmetabolites. In the ......We have developed a mathematical model describing the process of microbial enhanced oil recovery (MEOR). The one-dimensional isothermal model comprises displacement of oil bywater containing bacteria and substrate for their feeding. The bacterial products are both bacteria andmetabolites....... The characteristics for the water phase saturation profiles and the oil recovery curves are elucidated. However, the effect from the surfactant is not necessarily restricted to influence only interfacial tension, but it can also be an approach for changing, e.g., wettability. The distribution coefficient determines...... the time lag, until residual oil mobilization is initialized. It has also been found that the final recovery depends on the distance from the inlet before the surfactant effect takes place. The surfactant effect position is sensitive to changes in maximum growth rate, and injection concentrations...
Generation of 1D interference patterns of Bloch surface waves
Kadomina, E. A.; Bezus, E. A.; Doskolovich, L. L.
Interference patterns of Bloch surface waves with a period that is significantly less than the wavelength of incident radiation are formed using dielectric diffraction gratings located on the surface of photonic crystal. The simulation based on electromagnetic diffraction theory is used to demonstrate the possibility of high-quality interference patterns due to resonant enhancement of higher evanescent diffraction orders related to the excitation of the Bloch surface waves. The contrast of the interference patterns is close to unity, and the period is less than the period of the diffraction structure by an order of magnitude.
Topological defect formation in 1D and 2D spin chains realized by network of optical parametric oscillators
Hamerly, Ryan; Inagaki, Takahiro; Takesue, Hiroki; Yamamoto, Yoshihisa; Mabuchi, Hideo
A network of optical parametric oscillators is used to simulate classical Ising and XY spin chains. The collective nonlinear dynamics of this network, driven by quantum noise rather than thermal fluctuations, seeks out the Ising / XY ground state as the system transitions from below to above the lasing threshold. We study the behavior of this "Ising machine" for three canonical problems: a 1D ferromagnetic spin chain, a 2D square lattice, and problems where next-nearest-neighbor couplings give rise to frustration. If the pump turn-on time is finite, topological defects form (domain walls for the Ising model, winding number and vortices for XY) and their density can be predicted from a numerical model involving a linear "growth stage" and a nonlinear "saturation stage". These predictions are compared against recent data for a 10,000-spin 1D Ising machine.
Topological defect formation in 1D and 2D spin chains realized by network of optical parametric oscillators
Hamerly, Ryan; Inaba, Kensuke; Inagaki, Takahiro; Takesue, Hiroki; Yamamoto, Yoshihisa; Mabuchi, Hideo
A network of optical parametric oscillators (OPOs) is used to simulate classical Ising and XY spin chains. The collective nonlinear dynamics of this network, driven by quantum noise rather than thermal fluctuations, seeks out the Ising/XY ground state as the system transitions from below to above the lasing threshold. We study the behavior of this "Ising machine" for three canonical problems: a 1D ferromagnetic spin chain, a 2D square lattice and problems where next-nearest-neighbor couplings give rise to frustration. If the pump turn-on time is finite, topological defects form (domain walls for the Ising model, winding number and vortices for XY) and their density can be predicted from a numerical model involving a linear "growth stage" and a nonlinear "saturation stage". These predictions are compared against recent data for a 10,000-spin 1D Ising machine.
Comparison of 1D and 2D modelling with soil erosion model SMODERP
Kavka, Petr; Weyskrabova, Lenka; Zajicek, Jan
The contribution presents a comparison of a runoff simulated by profile method (1D) and spatially distributed method (2D). Simulation model SMODERP is used for calculation and prediction of soil erosion and surface runoff from agricultural land. SMODERP is physically based model that includes the processes of infiltration (Phillips equation), surface runoff (kinematic wave based equation), surface retention, surface roughness and vegetation impact on runoff. 1D model was developed in past, new 2D model was developed in last two years. The model is being developed at the Department of Irrigation, Drainage and Landscape Engineering, Civil Engineering Faculty, CTU in Prague. 2D model was developed as a tool for widespread GIS software ArcGIS. The physical relations were implemented through Python script. This script uses ArcGIS system tools for raster and vectors treatment of the inputs. Flow direction is calculated by Steepest Descent algorithm in the preliminary version of 2D model. More advanced multiple flow algorithm is planned in the next version. Spatially distributed models enable to estimate not only surface runoff but also flow in the rills. Surface runoff is described in the model by kinematic wave equation. Equation uses Manning roughness coefficient for surface runoff. Parameters for five different soil textures were calibrated on the set of forty measurements performed on the laboratory rainfall simulator. For modelling of the rills a specific sub model was created. This sub model uses Manning formula for flow estimation. Numerical stability of the model is solved by Courant criterion. Spatial scale is fixed. Time step is dynamically changed depending on how flow is generated and developed. SMODERP is meant to be used not only for the research purposes, but mainly for the engineering practice. We also present how the input data can be obtained based on available resources (soil maps and data, land use, terrain models, field research, etc.) and how can
Assessing the impact of different sources of topographic data on 1-D hydraulic modelling of floods
Ali, A. Md; Solomatine, D. P.; Di Baldassarre, G.
Topographic data, such as digital elevation models (DEMs), are essential input in flood inundation modelling. DEMs can be derived from several sources either through remote sensing techniques (spaceborne or airborne imagery) or from traditional methods (ground survey). The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), the Shuttle Radar Topography Mission (SRTM), the light detection and ranging (lidar), and topographic contour maps are some of the most commonly used sources of data for DEMs. These DEMs are characterized by different precision and accuracy. On the one hand, the spatial resolution of low-cost DEMs from satellite imagery, such as ASTER and SRTM, is rather coarse (around 30 to 90 m). On the other hand, the lidar technique is able to produce high-resolution DEMs (at around 1 m), but at a much higher cost. Lastly, contour mapping based on ground survey is time consuming, particularly for higher scales, and may not be possible for some remote areas. The use of these different sources of DEM obviously affects the results of flood inundation models. This paper shows and compares a number of 1-D hydraulic models developed using HEC-RAS as model code and the aforementioned sources of DEM as geometric input. To test model selection, the outcomes of the 1-D models were also compared, in terms of flood water levels, to the results of 2-D models (LISFLOOD-FP). The study was carried out on a reach of the Johor River, in Malaysia. The effect of the different sources of DEMs (and different resolutions) was investigated by considering the performance of the hydraulic models in simulating flood water levels as well as inundation maps. The outcomes of our study show that the use of different DEMs has serious implications to the results of hydraulic models. The outcomes also indicate that the loss of model accuracy due to re-sampling the highest resolution DEM (i.e. lidar 1 m) to lower resolution is much less than the loss of model accuracy due
Estimation of future groundwater recharge using climatic analogues and Hydrus-1D
Directory of Open Access Journals (Sweden)
B. Leterme
Full Text Available The impact of climate change on groundwater recharge is simulated using climatic analogue stations, i.e. stations presently under climatic conditions corresponding to a given climate state. The study was conducted in the context of a safety assessment of a future near-surface disposal facility for low and intermediate level short-lived radioactive waste in Belgium; this includes estimating groundwater recharge for the next millennia. Groundwater recharge was simulated using the Richard's based soil water balance model Hydrus-1D and meteorological time series from analogue stations. Water balance calculations showed that transition from a temperate oceanic to a warmer subtropical climate without rainfall seasonality is expected to yield a decrease in groundwater recharge (−12% for the chosen representative analogue station of Gijon, Northern Spain. Based on a time series of 24 yr of daily climate data, the long-term average annual recharge decreased from 314 to 276 mm, although total rainfall was higher (947 mm in the warmer climate compared to the current temperate climate (899 mm. This is due to a higher soil evaporation (233 mm versus 206 mm and higher plant transpiration (350 versus 285 mm under the warmer climate.
Sensitivity of groundwater recharge using climatic analogues and HYDRUS-1D
Directory of Open Access Journals (Sweden)
B. Leterme
Full Text Available The sensitivity of groundwater recharge to different climate conditions was simulated using the approach of climatic analogue stations, i.e. stations presently experiencing climatic conditions corresponding to a possible future climate state. The study was conducted in the context of a safety assessment of a future near-surface disposal facility for low and intermediate level short-lived radioactive waste in Belgium; this includes estimation of groundwater recharge for the next millennia. Groundwater recharge was simulated using the Richards based soil water balance model HYDRUS-1D and meteorological time series from analogue stations. This study used four analogue stations for a warmer subtropical climate with changes of average annual precipitation and potential evapotranspiration from −42% to +5% and from +8% to +82%, respectively, compared to the present-day climate. Resulting water balance calculations yielded a change in groundwater recharge ranging from a decrease of 72% to an increase of 3% for the four different analogue stations. The Gijon analogue station (Northern Spain, considered as the most representative for the near future climate state in the study area, shows an increase of 3% of groundwater recharge for a 5% increase of annual precipitation. Calculations for a colder (tundra climate showed a change in groundwater recharge ranging from a decrease of 97% to an increase of 32% for four different analogue stations, with an annual precipitation change from −69% to −14% compared to the present-day climate.
Application of particle trajectory model in 1D planar ejection
Institute of Scientific and Technical Information of China (English)
刘坤; 柏劲松; 李平
A simple one-dimensional planar model for ejection was set up based on experiments.And numerical simulation was performed on this model with particle trajectory model method.An Eulerian finite volume method was conducted to resolve gas field.And Lagrangian method was imposed to track each particle.The interaction between gas and particles was responded as source terms in governing equations which were induced by forces.The effects of total spraying mass,particle size and other factors on the mixture of particles and gas were investigated.The spatial distributions of particle mass and velocity at different time were presented.The result shows that the numerical results are qualitatively consistent to those of experiments.
Endogenous N-terminal Domain Cleavage Modulates α1D-Adrenergic Receptor Pharmacodynamics.
Kountz, Timothy S; Lee, Kyung-Soon; Aggarwal-Howarth, Stacey; Curran, Elizabeth; Park, Ji-Min; Harris, Dorathy-Ann; Stewart, Aaron; Hendrickson, Joseph; Camp, Nathan D; Wolf-Yadlin, Alejandro; Wang, Edith H; Scott, John D; Hague, Chris
The α1D-adrenergic receptor (ADRA1D) is a key regulator of cardiovascular, prostate, and central nervous system functions. This clinically relevant G protein-coupled receptor has proven difficult to study, as it must form an obligate modular homodimer containing the PDZ proteins scribble and syntrophin or become retained in the endoplasmic reticulum as non-functional protein. We previously determined that targeted removal of the N-terminal (NT) 79 amino acids facilitates ADRA1D plasma membrane expression and agonist-stimulated functional responses. However, whether such an event occurs in physiological contexts was unknown. Herein, we report the ADRA1D is subjected to innate NT processing in cultured human cells. SNAP near-infrared imaging and tandem-affinity purification revealed the ADRA1D is expressed as both full-length and NT truncated forms in multiple human cell lines. Serial truncation mapping identified the cleavage site as Leu(90)/Val(91) in the 95-amino acid ADRA1D NT domain, suggesting human cells express a Δ1-91 ADRA1D species. Tandem-affinity purification MS/MS and co-immunoprecipitation analysis indicate NT processing of ADRA1D is not required to form scribble-syntrophin macromolecular complexes. Yet, label-free dynamic mass redistribution signaling assays demonstrate that Δ1-91 ADRA1D agonist responses were greater than WT ADRA1D. Mutagenesis of the cleavage site nullified the processing event, resulting in ADRA1D agonist responses less than the WT receptor. Thus, we propose that processing of the ADRA1D NT domain is a physiological mechanism employed by cells to generate a functional ADRA1D isoform with optimal pharmacodynamic properties. PMID:27382054
Acute exercise and physiological insulin induce distinct phosphorylation signatures on TBC1D1 and TBC1D4 in human skeletal muscle
DEFF Research Database (Denmark)
Treebak, Jonas Thue; Pehmøller, Christian; Kristensen, Jonas Møller;
We investigated the phosphorylation signatures of two Rab GTPase activating proteins TBC1D1 and TBC1D4 in human skeletal muscle in response to physical exercise and physiological insulin levels induced by a carbohydrate rich meal using a paired experimental design. Eight healthy male volunteers...... in response to physiological stimuli in human skeletal muscle and support the idea that Akt and AMPK are upstream kinases. TBC1D1 phosphorylation signatures were comparable between in vitro contracted mouse skeletal muscle and exercised human muscle, and we show that AMPK was regulating phosphorylation...... of these sites in mouse muscle. Contraction and exercise elicited a different phosphorylation pattern of TBC1D4 in mouse compared with human muscle, and although different circumstances in our experimental setup may contribute to this difference, the observation exemplifies that transferring findings between...
COLUMN, 1-D Migration for Various Physical Chemical Processes
International Nuclear Information System (INIS)
1 - Description of problem or function: COLUMN2 is designed for studies of the effects various physicochemical processes on migration in one dimension. It solves the transport equation and can take into account dispersion, sorption, ion exchange, first and second order homogeneous chemical reactions. Spatial variations of input pulses and retention factors are possible. 2 - Method of solution: The Method of solution is based on a finite difference discretion followed by the application of the method of characteristics and two separate grid systems. 3 - Restrictions on the complexity of the problem: For computational reasons the number of components has been limited to 5 and the maximum number of second order reactions is 10. However, a re-dimensioning of all relevant arrays will allow for any number of components and reactions desired. Arrays should never be dimensioned larger than needed in order to save computation time. Five components and 10 second order reactions may seem a small number. However, larger simulations are often divided into smaller sub-problems for clarification purposes. The maximum number of grid points, default value 801, may be enlarged to re-dimensioning all relevant arrays
A realistic 3+1D Viscous Hydro Algorithm
Energy Technology Data Exchange (ETDEWEB)
Romatschke, Paul [Univ. of Colorado, Boulder, CO (United States)
DoE funds were used as bridge funds for the faculty position for the PI at the University of Colorado. The total funds for the Years 3-5 of the JET Topical Collaboration amounted to about 50 percent of the academic year salary of the PI.The PI contributed to the JET Topical Collaboration by developing, testing and applying algorithms for a realistic simulation of the bulk medium created in relativistic ion collisions.Specifically, two approaches were studied, one based on a new Lattice-Boltzmann (LB) framework, and one on a more traditional viscous hydro-dynamics framework. Both approaches were found to be viable in principle, with the LB approach being more elegant but needing still more time to develop.The traditional approach led to the super-hybrid model of ion collisions dubbed 'superSONIC', and has been successfully used for phenomenology of relativistic heavy-ion and light-on-heavy-ion collisions.In the time-frame of the JET Topical Collaboration, the Colorado group has published 15 articles in peer-reviewed journals, three of which were published in Physical Review Letters. The group graduated one Master student during this time-frame and two more PhD students are expected to graduate in the next few years. The PI has given more than 28 talks and presentations during this period.
关于图的L(d1,d2)-标号问题%The L(d1, d2)-Labeling Problem on Graphs
Institute of Scientific and Technical Information of China (English)
邵振东; 刘家壮
The L(2, 1)-labeling is formulated from the frequency assignment problem. We study the L(d1, d2)- labeling which is a generalization of the L(2, 1)-labeling. Vertex 2-coloring, 2-chromatic number and other related concepts are firstly defined, and the upper bound for 2-chromatic number is given; a very general relationship between λd1 ,d2 (G) and minimum degree δ(G) and maximum degree △(G) is then derived; finally, the upper bounds of L(d1, d2)-labelings of general and planar graphs are given.%图的L(2,1)-标号问题是由频率分配问题归结而来,本文研究作为L(2,1)-标号问题的推广的L(d1,d2)-标号问题.首先定义了顶点2-着色,2-色数及其它有关概念,给出了2-色数的上界.然后得出了λd1,d2(G)与δ(G)和△(G)的一般关系.最后得出了一般图与平面图的λd1,d2(G)的上界.
Expression of CD1d protein in human testis showing normal and abnormal spermatogenesis.
Adly, Mohamed A; Abdelwahed Hussein, Mahmoud-Rezk
CD1d is a member of CD1 family of transmembrane glycoproteins, which represent antigen-presenting molecules. Immunofluorescent staining methods were utilized to examine expression pattern of CD1d in human testicular specimens. In testis showing normal spermatogenesis, a strong CD1d cytoplasmic expression was seen the Sertoli cells, spermatogonia, and Leydig cells. A moderate expression was observed in the spermatocytes. In testes showing maturation arrest, CD1d expression was strong in the Sertoli cells and weak in spermatogonia and spermatocytes compared to testis with normal spermatogenesis. In Sertoli cell only syndrome, CD1d expression was strong in the Sertoli and Leydig cells. This preliminary study displayed testicular infertility-related changes in CD1d expression. The ultrastructural changes associated with with normal and abnormal spermatogenesis are open for further investigations.
Technical Note: Sensitivity of 1-D smoke plume rise models to the inclusion of environmental wind drag
Directory of Open Access Journals (Sweden)
S. R. Freitas
Full Text Available Vegetation fires emit hot gases and particles which are rapidly transported upward by the positive buoyancy generated by the combustion process. In general, the final vertical height that the smoke plumes reach is controlled by the thermodynamic stability of the atmospheric environment and the surface heat flux released by the fire. However, the presence of a strong horizontal wind can enhance the lateral entrainment and induce additional drag, particularly for small fires, impacting the smoke injection height. In this paper, we revisit the parameterization of the vertical transport of hot gases and particles emitted from vegetation fires, described in Freitas et al. (2007, to include the effects of environmental wind on transport and dilution of the smoke plume at its scale. This process is quantitatively represented by introducing an additional entrainment term to account for organized inflow of a mass of cooler and drier ambient air into the plume and its drag by momentum transfer. An extended set of equations including the horizontal motion of the plume and the additional increase of the plume radius is solved to simulate the time evolution of the plume rise and the smoke injection height. One-dimensional (1-D model results are presented for two deforestation fires in the Amazon basin with sizes of 10 and 50 ha under calm and windy atmospheric environments. The results are compared to corresponding simulations generated by the complex non-hydrostatic three-dimensional (3-D Active Tracer High resolution Atmospheric Model (ATHAM. We show that the 1-D model results compare well with the full 3-D simulations. The 1-D model may thus be used in field situations where extensive computing facilities are not available, especially under conditions for which several optional cases must be studied.
Energy exchange between (3+1)D colliding spatiotemporal optical solitons in dispersive media with cubic-quintic nonlinearity
Institute of Scientific and Technical Information of China (English)
Yang Hong; Tang Yi
We investigate the energy exchange between (3+1)D colliding spatiotemporal solitons (STSs) in dispersive media with cubic-quintic (CQ) nonlinearity by numerical simulations. Energy exchange between two (3+l)D head on colliding STSs caused by their phase difference is observed, just as occurring in other optical media. Moreover, energy exchange between two head-on colliding STSs with different speeds is firstly shown in the CQ and saturable media.This phenomenon, we believe, may arouse some interest in the future studies of soliton collision in optical media.
Development of a 1D-2D coupled hydrodynamic model for the Øyeren Delta in southern Norway
In this study a coupled 1D-2D hydrodynamic model, MIKE FLOOD was used to simulate flood inundation extent, water levels and water velocities in the delta region of Lake Øyeren in southern Norway. The objective was to evaluate the improvement gained using a more complex framework. In addition, the credibility of existing flood zone maps made for Lillestrøm by Norges Vassdrag- og Energidirektorat (NVE) in 2005 was assessed. They were based on the assumption that the water levels predicted for F...
Partitioning of evaporation into transpiration, soil evaporation and interception: a comparison between isotope measurements and a HYDRUS-1D model
Directory of Open Access Journals (Sweden)
S. J. Sutanto
Full Text Available Knowledge of the water fluxes within the soil-vegetation-atmosphere system is crucial to improve water use efficiency in irrigated land. Many studies have tried to quantify these fluxes, but they encountered difficulties in quantifying the relative contribution of evaporation and transpiration. In this study, we compared three different methods to estimate evaporation fluxes during simulated summer conditions in a grass-covered lysimeter in the laboratory. Only two of these methods can be used to partition total evaporation into transpiration, soil evaporation and interception. A water balance calculation (whereby rainfall, soil moisture and percolation were measured was used for comparison as a benchmark. A HYDRUS-1D model and isotope measurements were used for the partitioning of total evaporation. The isotope mass balance method partitions total evaporation of 3.4 mm d−1 into 0.4 mm d−1 for soil evaporation, 0.3 mm d−1 for interception and 2.6 mm d−1 for transpiration, while the HYDRUS-1D partitions total evaporation of 3.7 mm d−1 into 1 mm d−1 for soil evaporation, 0.3 mm d−1 for interception and 2.3 mm d−1 for transpiration. From the comparison, we concluded that the isotope mass balance is better for low temporal resolution analysis than the HYDRUS-1D. On the other hand, HYDRUS-1D is better for high temporal resolution analysis than the isotope mass balance.
Potent neutralizing anti-CD1d antibody reduces lung cytokine release in primate asthma model.
Nambiar, Jonathan; Clarke, Adam W; Shim, Doris; Mabon, David; Tian, Chen; Windloch, Karolina; Buhmann, Chris; Corazon, Beau; Lindgren, Matilda; Pollard, Matthew; Domagala, Teresa; Poulton, Lynn; Doyle, Anthony G
CD1d is a receptor on antigen-presenting cells involved in triggering cell populations, particularly natural killer T (NKT) cells, to release high levels of cytokines. NKT cells are implicated in asthma pathology and blockade of the CD1d/NKT cell pathway may have therapeutic potential. We developed a potent anti-human CD1d antibody (NIB.2) that possesses high affinity for human and cynomolgus macaque CD1d (KD ∼100 pM) and strong neutralizing activity in human primary cell-based assays (IC50 typically <100 pM). By epitope mapping experiments, we showed that NIB.2 binds to CD1d in close proximity to the interface of CD1d and the Type 1 NKT cell receptor β-chain. Together with data showing that NIB.2 inhibited stimulation via CD1d loaded with different glycolipids, this supports a mechanism whereby NIB.2 inhibits NKT cell activation by inhibiting Type 1 NKT cell receptor β-chain interactions with CD1d, independent of the lipid antigen in the CD1d antigen-binding cleft. The strong in vitro potency of NIB.2 was reflected in vivo in an Ascaris suum cynomolgus macaque asthma model. Compared with vehicle control, NIB.2 treatment significantly reduced bronchoalveolar lavage (BAL) levels of Ascaris-induced cytokines IL-5, IL-8 and IL-1 receptor antagonist, and significantly reduced baseline levels of GM-CSF, IL-6, IL-15, IL-12/23p40, MIP-1α, MIP-1β, and VEGF. At a cellular population level NIB.2 also reduced numbers of BAL lymphocytes and macrophages, and blood eosinophils and basophils. We demonstrate that anti-CD1d antibody blockade of the CD1d/NKT pathway modulates inflammatory parameters in vivo in a primate inflammation model, with therapeutic potential for diseases where the local cytokine milieu is critical.
Potent neutralizing anti-CD1d antibody reduces lung cytokine release in primate asthma model
Nambiar, Jonathan; Clarke, Adam W; Shim, Doris; Mabon, David; Tian, Chen; Windloch, Karolina; Buhmann, Chris; Corazon, Beau; Lindgren, Matilda; Pollard, Matthew; Domagala, Teresa; Poulton, Lynn; Doyle, Anthony G
CD1d is a receptor on antigen-presenting cells involved in triggering cell populations, particularly natural killer T (NKT) cells, to release high levels of cytokines. NKT cells are implicated in asthma pathology and blockade of the CD1d/NKT cell pathway may have therapeutic potential. We developed a potent anti-human CD1d antibody (NIB.2) that possesses high affinity for human and cynomolgus macaque CD1d (KD ∼100 pM) and strong neutralizing activity in human primary cell-based assays (IC50 typically <100 pM). By epitope mapping experiments, we showed that NIB.2 binds to CD1d in close proximity to the interface of CD1d and the Type 1 NKT cell receptor β-chain. Together with data showing that NIB.2 inhibited stimulation via CD1d loaded with different glycolipids, this supports a mechanism whereby NIB.2 inhibits NKT cell activation by inhibiting Type 1 NKT cell receptor β-chain interactions with CD1d, independent of the lipid antigen in the CD1d antigen-binding cleft. The strong in vitro potency of NIB.2 was reflected in vivo in an Ascaris suum cynomolgus macaque asthma model. Compared with vehicle control, NIB.2 treatment significantly reduced bronchoalveolar lavage (BAL) levels of Ascaris-induced cytokines IL-5, IL-8 and IL-1 receptor antagonist, and significantly reduced baseline levels of GM-CSF, IL-6, IL-15, IL-12/23p40, MIP-1α, MIP-1β, and VEGF. At a cellular population level NIB.2 also reduced numbers of BAL lymphocytes and macrophages, and blood eosinophils and basophils. We demonstrate that anti-CD1d antibody blockade of the CD1d/NKT pathway modulates inflammatory parameters in vivo in a primate inflammation model, with therapeutic potential for diseases where the local cytokine milieu is critical. PMID:25751125
Mapping of the serotonin 5-HT{sub 1D{alpha}} autoreceptor gene (HTR1D) on chromosome 1 using a silent polymorphism in the coding region
Energy Technology Data Exchange (ETDEWEB)
Ozaki, N.; Lappalainen, J.; Linnoila, M. [National Institute on Alcohol Abuse and Alcoholism, Rockville, MD (United States)] [and others
Serotonin (5-HT){sub ID} receptors are 5-HT release-regulating autoreceptors in the human brain. Abnormalities in brain 5-HT function have been hypothesized in the pathophysiology of various psychiatric disorders, including obsessive-compulsive disorder, autism, mood disorders, eating disorders, impulsive violent behavior, and alcoholism. Thus, mutations occurring in 5-HT autoreceptors may cause or increase the vulnerability to any of these conditions. 5-HT{sub 1D{alpha}} and 5-HT{sub 1D{Beta}} subtypes have been previously localized to chromosomes 1p36.3-p34.3 and 6q13, respectively, using rodent-human hybrids and in situ localization. In this communication, we report the detection of a 5-HT{sub 1D{alpha}} receptor gene polymorphism by single strand conformation polymorphism (SSCP) analysis of the coding sequence. The polymorphism was used for fine scale linkage mapping of 5-HT{sub 1D{alpha}} on chromosome 1. This polymorphism should also be useful for linkage studies in populations and in families. Our analysis also demonstrates that functionally significant coding sequence variants of the 5-HT{sub 1D{alpha}} are probably not abundant either among alcoholics or in the general population. 14 refs., 1 fig., 1 tab.
Approach for computing 1D fracture density: application to fracture corridor characterization
Viseur, Sophie; Chatelée, Sebastien; Akriche, Clement; Lamarche, Juliette
Fracture density is an important parameter for characterizing fractured reservoirs. Many stochastic simulation algorithms that generate fracture networks indeed rely on the determination of a fracture density on volumes (P30) to populate the reservoir zones with individual fracture surfaces. However, only 1D fracture density (P10) are available from subsurface data and it is then important to be able to accurately estimate this entity. In this paper, a novel approach is proposed to estimate fracture density from scan-line or well data. This method relies on regression, hypothesis testing and clustering techniques. The objective of the proposed approach is to highlight zones where fracture density are statistically very different or similar. This technique has been applied on both synthetic and real case studies. These studies concern fracture corridors, which are particular tectonic features that are generally difficult to characterize from subsurface data. These tectonic features are still not well known and studies must be conducted to better understand their internal spatial organization and variability. The presented synthetic cases aim at showing the ability of the approach to extract known features. The real case study illustrates how this approach allows the internal spatial organization of fracture corridors to be characterized.
A grid of 1D low-mass star formation collapse models
Vaytet, Neil
The current study was developed to provide a database of relatively simple numerical simulations of protostellar collapse, as a template library for observations of cores and very young protostars, and for researchers who wish to test their chemical modeling under dynamic astrophysical conditions. It was also designed to identify statistical trends that may appear when running many models of the formation of low-mass stars by varying the initial conditions. A large set of 143 calculations of the gravitational collapse of an isolated sphere of gas with uniform temperature and a Bonnor-Ebert like density profile was undertaken using a 1D fully implicit Lagrangian radiation hydrodynamics code. The parameter space covered initial masses from 0.2 to 8 Msun, temperatures of 5-30 K and radii between 3000 and 30,000 AU. A spread in the thermal evolutionary tracks of the runs was found, due to differing initial conditions and optical depths. Within less than an order of magnitude, all first and second Larson cores had...
Application of HYDRUS 1D model for assessment of phenol-soil adsorption dynamics.
Pal, Supriya; Mukherjee, Somnath; Ghosh, Sudipta
Laboratory-scale batch, vertical, and horizontal column experiments were conducted to investigate the attenuative capacity of a fine-grained clayey soil of local origin in the surrounding of a steel plant wastewater discharge site in West Bengal, India, for removal of phenol. Linear, Langmuir, and Freundlich isotherm plots from batch experimental data revealed that Freundlich isotherm model was reasonably fitted (R (2) = 0.94). The breakthrough column experiments were also carried out with different soil bed heights (5, 10, and 15 cm) under uniform flow to study the hydraulic movements of phenol by evaluating time concentration flow behavior using bromide as a tracer. The horizontal migration test was also conducted in the laboratory using adsorptive phenol and nonreactive bromide tracer to explore the movement of solute in a horizontal distance. The hydrodynamic dispersion coefficients (D) in the vertical and horizontal directions in the soil were estimated using nonlinear least-square parameter optimization method in CXTFIT model. In addition, the equilibrium convection dispersion model in HYDRUS 1D was also examined to simulate the fate and transport of phenol in vertical and horizontal directions using Freundlich isotherm constants and estimated hydrodynamic parameters as input in the model. The model efficacy and validation were examined through statistical parameters such as the coefficient of determination (R (2)), root mean square error and design of index (d). PMID:24407784
A New 2D-Transport, 1D-Diffusion Approximation of the Boltzmann Transport equation
Energy Technology Data Exchange (ETDEWEB)
Larsen, Edward
The work performed in this project consisted of the derivation, implementation, and testing of a new, computationally advantageous approximation to the 3D Boltz- mann transport equation. The solution of the Boltzmann equation is the neutron flux in nuclear reactor cores and shields, but solving this equation is difficult and costly. The new "2D/1D" approximation takes advantage of a special geometric feature of typical 3D reactors to approximate the neutron transport physics in a specific (ax- ial) direction, but not in the other two (radial) directions. The resulting equation is much less expensive to solve computationally, and its solutions are expected to be sufficiently accurate for many practical problems. In this project we formulated the new equation, discretized it using standard methods, developed a stable itera- tion scheme for solving the equation, implemented the new numerical scheme in the MPACT code, and tested the method on several realistic problems. All the hoped- for features of this new approximation were seen. For large, difficult problems, the resulting 2D/1D solution is highly accurate, and is calculated about 100 times faster than a 3D discrete ordinates simulation.
Reprint of : Connection between wave transport through disordered 1D waveguides and energy density inside the sample: A maximum-entropy approach
Mello, Pier A.; Shi, Zhou; Genack, Azriel Z.
We study the average energy - or particle - density of waves inside disordered 1D multiply-scattering media. We extend the transfer-matrix technique that was used in the past for the calculation of the intensity beyond the sample to study the intensity in the interior of the sample by considering the transfer matrices of the two segments that form the entire waveguide. The statistical properties of the two disordered segments are found using a maximum-entropy ansatz subject to appropriate constraints. The theoretical expressions are shown to be in excellent agreement with 1D transfer-matrix simulations.
1D Grating structures designed by the time domain topology optimization
DEFF Research Database (Denmark)
Yang, Lirong; Lavrinenko, Andrei; Sigmund, Ole;
We report on the time domain application of topology optimization to 1D photonic devices. The method is confirmed to converge to the global minimum when optimizing a Bragg grating structure.......We report on the time domain application of topology optimization to 1D photonic devices. The method is confirmed to converge to the global minimum when optimizing a Bragg grating structure....
Data of evolutionary structure change: 1B99C-2AZ1D [Confc[Archive
Lifescience Database Archive (English)
Full Text Available GSDS--VESAN >E --HHHHH> ATOM 316...>D 2AZ1D HGSDHEDEGANE >E HHH...pdbID>1B99 C 1B99C EELLT-EVKPN ...> - > ATOM 3319 CA GLU C 141 17.330 5.755...DChain>2AZ1D DELVDWDRDAS re>GG EEGGHcture
Data of evolutionary structure change: 1D5NC-1UNFX [Confc[Archive
Lifescience Database Archive (English)
Full Text Available msd> 1.0891029834747314 EVID> 1 1UNF...1D5NC-1UNFX 1D5N 1UNF C X ----SYTLPSLPYAYDALEPHFDKQTMEIHHTKHHQTYV...NNANAALESL----PEFANLPVEELITKLDQLPADKKTVL---------RNNAGGHANHSLFWKGLKKGT--TLQGDLKAAIERDFGSVDNFKAEFEKAAASRFGSGW...HH EVID> 0 TRP CA 380 1UNF X 1UNF
Data of evolutionary structure change: 1D5ND-1UNFX [Confc[Archive
Lifescience Database Archive (English)
Full Text Available 1.0915240049362183 EVID> 1 1UNF...1D5ND-1UNFX 1D5N 1UNF D X ----SYTLPSLPYAYDALEPHFDKQTMEIHHTKHHQTYV...NNANAALESL----PEFANLPVEELITKLDQLPADKKTVL---------RNNAGGHANHSLFWKGLKKGTT--LQGDLKAAIERDFGSVDNFKAEFEKAAASRFGSGW...H EVID> 0 TRP CA 379 1UNF X 1UNF
Comparison of the 1D flux theory with a 2D hydrodynamic secondary settling tank model.
Ekama, G A; Marais, P
The applicability of the 1D idealized flux theory (1DFT) for design of secondary settling tanks (SSTs) is evaluated by comparing its predicted maximum surface overflow (SOR) and solids loading (SLR) rates with that calculated from the 2D hydrodynamic model SettlerCAD using as a basis 35 full scale SST stress tests conducted on different SSTs with diameters from 30 to 45m and 2.25 to 4.1 m side water depth, with and without Stamford baffles. From the simulations, a relatively consistent pattern appeared, i.e. that the 1DFT can be used for design but its predicted maximum SLR needs to be reduced by an appropriate flux rating, the magnitude of which depends mainly on SST depth and hydraulic loading rate (HLR). Simulations of the sloping bottom shallow (1.5-2.5 m SWD) Dutch SSTs tested by STOWa and the Watts et al. SST, all with doubled SWDs, and the Darvill new (4.1 m) and old (2.5 m) SSTs with interchanged depths, were run to confirm the sensitivity of the flux rating to depth and HLR. Simulations with and without a Stamford baffle were also done. While the design of the internal features of the SST, such as baffling, have a marked influence on the effluent SS concentration for underloaded SSTs, these features appeared to have only a small influence on the flux rating, i.e. capacity, of the SST, In the meantime until more information is obtained, it would appear that from the simulations so far that the flux rating of 0.80 of the 1DFT maximum SLR recommended by Ekama and Marais remains a reasonable value to apply in the design of full scale SSTs--for deep SSTs (4 m SWD) the flux rating could be increased to 0.85 and for shallow SSTs (2.5 m SWD) decreased to 0.75. It is recommended that (i) while the apparent interrelationship between SST flux rating and depth suggests some optimization of the volume of the SST, that this be avoided and that (ii) the depth of the SST be designed independently of the surface area as is usually the practice and once selected, the
Identification of RAPD Marker for Chromosome 1D of Common Wheat
Directory of Open Access Journals (Sweden)
Imtiaz Ahmad Khan
Full Text Available Development of genetically compensating nullisomic-tetrasomic and ditelosomic lines of commonwheat (Triticum aestivum L. have been widely used to construct high density genetic maps of homoeologouswheat chromosomes. During present research, easier, cheaper and quicker procedure of Polymerase ChainReaction (PCR was used to map Randomly Amplified Polymorphic DNA primers on chromosome 1D ofcommon wheat. Genomic DNA was isolated from two genetic stocks of wheat cultivar Chinese Spring viz;NT-1D1B and NT-2A2B. PCR were conducted using RAPD primers GLC-07 and GLC-11. RAPD primerGLC-11 amplified a polymorphic allele of approximately 500 bp, which was present in NT-2A2B (used aspositive control but was absent in NT-1D1B indicating that the locus is present on chromosome 1D of commonwheat. Hence this marker (GLC-11 can reliably be used to keep track of chromosome 1D of hexaploid wheat.
Alternative spliced CD1d transcripts in human bronchial epithelial cells.
Directory of Open Access Journals (Sweden)
Kambez Hajipouran Benam
Full Text Available CD1d is a MHC I like molecule which presents glycolipid to natural killer T (NKT cells, a group of cells with diverse but critical immune regulatory functions in the immune system. These cells are required for optimal defence against bacterial, viral, protozoan, and fungal infections, and control of immune-pathology and autoimmune diseases. CD1d is expressed on antigen presenting cells but also found on some non-haematopoietic cells. However, it has not been observed on bronchial epithelium, a site of active host defence in the lungs. Here, we identify for the first time, CD1D mRNA variants and CD1d protein expression on human bronchial epithelial cells, describe six alternatively spliced transcripts of this gene in these cells; and show that these variants are specific to epithelial cells. These findings provide the basis for investigations into a role for CD1d in lung mucosal immunity.
Significance of flow clustering and sequencing on sediment transport: 1D sediment transport modelling
Hassan, Kazi; Allen, Deonie; Haynes, Heather
This paper considers 1D hydraulic model data on the effect of high flow clusters and sequencing on sediment transport. Using observed flow gauge data from the River Caldew, England, a novel stochastic modelling approach was developed in order to create alternative 50 year flow sequences. Whilst the observed probability density of gauge data was preserved in all sequences, the order in which those flows occurred was varied using the output from a Hidden Markov Model (HMM) with generalised Pareto distribution (GP). In total, one hundred 50 year synthetic flow series were generated and used as the inflow boundary conditions for individual flow series model runs using the 1D sediment transport model HEC-RAS. The model routed graded sediment through the case study river reach to define the long-term morphological changes. Comparison of individual simulations provided a detailed understanding of the sensitivity of channel capacity to flow sequence. Specifically, each 50 year synthetic flow sequence was analysed using a 3-month, 6-month or 12-month rolling window approach and classified for clusters in peak discharge. As a cluster is described as a temporal grouping of flow events above a specified threshold, the threshold condition used herein is considered as a morphologically active channel forming discharge event. Thus, clusters were identified for peak discharges in excess of 10%, 20%, 50%, 100% and 150% of the 1 year Return Period (RP) event. The window of above-peak flows also required cluster definition and was tested for timeframes 1, 2, 10 and 30 days. Subsequently, clusters could be described in terms of the number of events, maximum peak flow discharge, cumulative flow discharge and skewness (i.e. a description of the flow sequence). The model output for each cluster was analysed for the cumulative flow volume and cumulative sediment transport (mass). This was then compared to the total sediment transport of a single flow event of equivalent flow volume
Optical bullets in (2+1)D photonic structures and their interaction with localized defects
Dohnal, Tomas
This dissertation studies light propagation in Kerr-nonlinear two dimensional waveguides with a Bragg resonant, periodic structure in the propagation direction. The model describing evolution of the electric field envelopes is the system of 2D Nonlinear Coupled Mode Equations (2D CME). The periodic structure induces a range of frequencies (frequency gap) in which linear waves do not propagate. It is shown that, similarly to the ID case of a fiber grating, the 2D nonlinear system supports localized solitary wave solutions, referred to as 2D gap solitons, which have frequencies inside the linear gap and can travel at, any speed smaller than or equal to the speed of light in the corresponding homogeneous medium. Such solutions are constructed numerically via Newton's iteration. Convergence is obtained only near the upper edge of the gap. Gap solitons with a nonzero velocity are constructed by numerically following a bifurcation curve parameterized by the velocity v. It is shown that gap solitons are saddle points of the corresponding Hamiltonian functional and that no (constrained) local minima of the Hamiltonian exist. The linear stability problem is formulated and reasons for the failure of the standard Hamiltonian PDE approach for determining linear stability are discussed. In the second part of the dissertation interaction of 2D gap solitons with localized defects is studied and trapping of slow enough 2D gap solitons is demonstrated. This study builds on [JOSA B 19, 1635 (2002)], where such trapping of 1D gap solitons is considered. Analogously to this 1D problem trapping in the 2D model is explained as a resonant energy transfer into one or more defect modes existent for the particular defect. For special localized defects exact linear modes are found explicitly via the separation of variables. Numerical computation of linear defect modes is used for more general defects. Corresponding nonlinear modes are then constructed via Newton's iteration by following a
Dependence of cross-relaxation on temperature and concentration from the {sup 1}D{sub 2} level of Pr{sup 3+} in YPO{sub 4}
Energy Technology Data Exchange (ETDEWEB)
Collins, John, E-mail: email@example.com [Department of Physics and Astronomy,Wheaton College, Norton, MA 02766 (United States); Geen, Megan [Department of Physics and Astronomy,Wheaton College, Norton, MA 02766 (United States); Bettinelli, M. [Dipartmento di Biotechnologie, Universita Delgi Studi di Verona, Verona (Italy); Di Bartolo, B. [Department of Physics, Boston College, Chestnut Hill, MA 02467 (United States)
We report on the role of cross-relaxation in the decay of the {sup 1}D{sub 2} level of trivalent Pr in YPO{sub 4} in crystals with Pr concentrations of 0.1%, 1%, 2%, and 5%. We have found that the {sup 1}D{sub 2} level decay is purely radiative in the low-doped system. As the Pr concentration is increased, the {sup 1}D{sub 2} luminescence is quenched due to a cross-relaxation energy transfer between two Pr ions. The temporal behavior of the {sup 1}D{sub 2} luminescence following pulsed excitation has been monitored in each sample at temperatures between 30 K and 300 K, and all decay curves were fit to the Yokota-Tanimoto model. The decay times decrease as temperature increases, due to an increase in both the radiative rate and the energy transfer rate with temperature. There is little evidence of diffusion at any temperature, even in the more concentrated samples. We have also fit the decay curves using the LumiTrans computer simulation. A comparison of the fits to the decay curves of the two methods is presented. - Highlights: Black-Right-Pointing-Pointer We present data on the decay of the {sup 1}D{sub 2} level of Pr in YPO{sub 4} from 30-300 K. Black-Right-Pointing-Pointer We determine the {sup 1}D{sub 2} cross-relaxation rate throughout that temperature range. Black-Right-Pointing-Pointer Fits to the data indicate diffusion among the Pr ions is negligible. Black-Right-Pointing-Pointer Radiative efficiencies of the {sup 1}D{sub 2} level are determined.
Visible light dynamical diffraction in a 1-D photonic crystal-based interferometer with an extremely thin spacer layer
Prudnikov, I. R.
Properties of light diffraction in a Fabry-Pérot-like interferometer composed of two 1-D photonic crystals and a nanometer-thick spacer layer are analytically investigated. It is shown that the resonant enhancement of light wave intensity in such a layer is possible because of light dynamical diffraction from the photonic crystals of the interferometer. Numerical simulations of (i) light reflectivity and transmittance curves of the interferometer having an ultra-thin spacer layer (its thickness changes from less than 1 nm to about 10 nm) and (ii) the resonant distribution of the light wave intensity in the vicinity of the layer are performed. Based on the numerical simulations, potentialities for the determination of the structural parameters (e.g., thicknesses and refraction indexes) of ultra-thin spacer films are discussed. A difference is found to appear in resonant intensity enhancements inside the ultra-thin spacer layers between s- and p-polarized light waves.
Optimizing the Emitter Layer for Higher Efficiency Solar Cell Based SiGe Using AMPS1D
Directory of Open Access Journals (Sweden)
Boukais Meriem
Full Text Available The thin-film SiGe is considered as promising candidate to meet the outstanding need for photovoltaic applications with enhanced adsorption characteristics and improved conversion efficiency [1-6]. In this paper, we simulated a solar cell type SiGe using AMPS1D (Analysis of Microelectronic and photonic structure developed at Pennsylvania State University, to analyze emitter layer (thickness, doping and we studied their influence on the photovoltaic solar cell. The simulation result shows that the maximum efficiency of 16.181 % has been achieved, with short circuit current density of 32.657 mA/cm2, open circuit voltage of 0.61 V and fill factor of 0.809. The obtained results show that the proposed design can be considered as a potential candidate for high performance photovoltaic applications.
Institute of Scientific and Technical Information of China (English)
HAN Dong; FANG Hong-wei; BAI Jing; HE Guo-jian
A coupled one-dimensional(1-D)and two-dimensional(2-D)channel network mathematical model is proposed for flow calculations at nodes in a channel network system in this article.For the 1-D model,the finite difference method is used to discretize the Saint-Venant equations in all channels of a looped network.The Alternating Direction Implicit(ADI)method is adopted for the 2-D model at the nodes.In the coupled model,the 1-D model provides a good approximation with small computational effort,while the 2-D model is applied for complex topography to achieve a high accuracy.An Artificial Neural Network(ANN)method is used for the data exchange and the connectivity between the 1-D and 2-D models.The coupled model is applied to the Jingjiang-Dongting Lake region,to simulate the tremendous looped channel network system,and the results are compared with field data.The good agreement shows that the coupled hydraulic model is more effective than the conventional 1-D model.
Use of optimized 1D TOCSY NMR for improved quantitation and metabolomic analysis of biofluids
Energy Technology Data Exchange (ETDEWEB)
Sandusky, Peter [Eckerd College, Department of Chemistry (United States); Appiah-Amponsah, Emmanuel; Raftery, Daniel, E-mail: firstname.lastname@example.com [Purdue University, Department of Chemistry (United States)
One dimensional selective TOCSY experiments have been shown to be advantageous in providing improved data inputs for principle component analysis (PCA) (Sandusky and Raftery 2005a, b). Better subpopulation cluster resolution in the observed scores plots results from the ability to isolate metabolite signals of interest via the TOCSY based filtering approach. This report reexamines the quantitative aspects of this approach, first by optimizing the 1D TOCSY experiment as it relates to the measurement of biofluid constituent concentrations, and second by comparing the integration of 1D TOCSY read peaks to the bucket integration of 1D proton NMR spectra in terms of precision and accuracy. This comparison indicates that, because of the extensive peak overlap that occurs in the 1D proton NMR spectra of biofluid samples, bucket integrals are often far less accurate as measures of individual constituent concentrations than 1D TOCSY read peaks. Even spectral fitting approaches have proven difficult in the analysis of significantly overlapped spectral regions. Measurements of endogenous taurine made over a sample population of human urine demonstrates that, due to background signals from other constituents, bucket integrals of 1D proton spectra routinely overestimate the taurine concentrations and distort its variation over the sample population. As a result, PCA calculations performed using data matrices incorporating 1D TOCSY determined taurine concentrations produce better scores plot subpopulation cluster resolution.
TBC1D14 regulates autophagy via the TRAPP complex and ATG9 traffic.
Lamb, Christopher A; Nühlen, Stefanie; Judith, Delphine; Frith, David; Snijders, Ambrosius P; Behrends, Christian; Tooze, Sharon A
Macroautophagy requires membrane trafficking and remodelling to form the autophagosome and deliver its contents to lysosomes for degradation. We have previously identified the TBC domain-containing protein, TBC1D14, as a negative regulator of autophagy that controls delivery of membranes from RAB11-positive recycling endosomes to forming autophagosomes. In this study, we identify the TRAPP complex, a multi-subunit tethering complex and GEF for RAB1, as an interactor of TBC1D14. TBC1D14 binds to the TRAPP complex via an N-terminal 103 amino acid region, and overexpression of this region inhibits both autophagy and secretory traffic. TRAPPC8, the mammalian orthologue of a yeast autophagy-specific TRAPP subunit, forms part of a mammalian TRAPPIII-like complex and both this complex and TBC1D14 are needed for RAB1 activation. TRAPPC8 modulates autophagy and secretory trafficking and is required for TBC1D14 to bind TRAPPIII. Importantly, TBC1D14 and TRAPPIII regulate ATG9 trafficking independently of ULK1. We propose a model whereby TBC1D14 and TRAPPIII regulate a constitutive trafficking step from peripheral recycling endosomes to the early Golgi, maintaining the cycling pool of ATG9 required for initiation of autophagy. PMID:26711178
Estimation of exhaust gas aerodynamic force on the variable geometry turbocharger actuator: 1D flow model approach
International Nuclear Information System (INIS)
Highlights: • Estimation of aerodynamic force on variable turbine geometry vanes and actuator. • Method based on exhaust gas flow modeling. • Simulation tool for integration of aerodynamic force in automotive simulation software. - Abstract: This paper provides a reliable tool for simulating the effects of exhaust gas flow through the variable turbine geometry section of a variable geometry turbocharger (VGT), on flow control mechanism. The main objective is to estimate the resistive aerodynamic force exerted by the flow upon the variable geometry vanes and the controlling actuator, in order to improve the control of vane angles. To achieve this, a 1D model of the exhaust flow is developed using Navier–Stokes equations. As the flow characteristics depend upon the volute geometry, impeller blade force and the existing viscous friction, the related source terms (losses) are also included in the model. In order to guarantee stability, an implicit numerical solver has been developed for the resolution of the Navier–Stokes problem. The resulting simulation tool has been validated through comparison with experimentally obtained values of turbine inlet pressure and the aerodynamic force as measured at the actuator shaft. The simulator shows good compliance with experimental results
On the Current Drive Capability of Low Dimensional Semiconductors: 1D versus 2D.
Zhu, Y; Appenzeller, J
Low-dimensional electronic systems are at the heart of many scaling approaches currently pursuit for electronic applications. Here, we present a comparative study between an array of one-dimensional (1D) channels and its two-dimensional (2D) counterpart in terms of current drive capability. Our findings from analytical expressions derived in this article reveal that under certain conditions an array of 1D channels can outperform a 2D field-effect transistor because of the added degree of freedom to adjust the threshold voltage in an array of 1D devices.
Development of a 1D neutron transport code employing the method of characteristics
International Nuclear Information System (INIS)
To investigate the 2D/1D fusion core analysis method, a 1D neutron transport problem solver, PEACH-ID, is developed. It is a code of method of characteristics (MOC), both the usual fiat-source step characteristics (SC) scheme and linear source (LS) approximation scheme are adopted for tracking calculation along the neutron flying trajectory. Exponential function interpolation table and fission source extrapolation are adopted as two major methods to accelerate the computational process. Numerical results demonstrate that PEACH-1D is accurate and efficient, and the proposed LS scheme is able to handle quite larger mesh division and deserves much more application in the MOC codes. (authors)
TCTEX1D2 mutations underlie Jeune asphyxiating thoracic dystrophy with impaired retrograde intraflagellar transport
Schmidts, Miriam; Hou, Yuqing; Cortés, Claudio R.; Mans, Dorus A.; Huber, Celine; Boldt, Karsten; Patel, Mitali; van Reeuwijk, Jeroen; Plaza, Jean-Marc; van Beersum, Sylvia E. C.; Yap, Zhi Min; Letteboer, Stef J. F.; Taylor, S. Paige; Herridge, Warren; Johnson, Colin A.; Scambler, Peter J.; Ueffing, Marius; Kayserili, Hulya; Krakow, Deborah; King, Stephen M.; Beales, Philip L.; Al-Gazali, Lihadh; Wicking, Carol; Cormier-Daire, Valerie; Roepman, Ronald; Mitchison, Hannah M.; Witman, George B.; Al-Turki, Saeed; Anderson, Carl; Anney, Richard; Antony, Dinu; Asimit, Jennifer; Ayub, Mohammad; Barrett, Jeff; Barroso, Inês; Bentham, Jamie; Bhattacharya, Shoumo; Blackwood, Douglas; Bobrow, Martin; Bochukova, Elena; Bolton, Patrick; Boustred, Chris; Breen, Gerome; Brion, Marie-Jo; Brown, Andrew; Calissano, Mattia; Carss, Keren; Chatterjee, Krishna; Chen, Lu; Cirak, Sebhattin; Clapham, Peter; Clement, Gail; Coates, Guy; Collier, David; Cosgrove, Catherine; Cox, Tony; Craddock, Nick; Crooks, Lucy; Curran, Sarah; Daly, Allan; Danecek, Petr; Smith, George Davey; Day-Williams, Aaron; Day, Ian; Durbin, Richard; Edkins, Sarah; Ellis, Peter; Evans, David; Farooqi, I. Sadaf; Fatemifar, Ghazaleh; Fitzpatrick, David; Flicek, Paul; Floyd, Jamie; Foley, A. Reghan; Franklin, Chris; Futema, Marta; Gallagher, Louise; Gaunt, Tom; Geschwind, Daniel; Greenwood, Celia; Grozeva, Detelina; Guo, Xiaosen; Gurling, Hugh; Hart, Deborah; Hendricks, Audrey; Holmans, Peter; Huang, Jie; Humphries, Steve E.; Hurles, Matt; Hysi, Pirro; Jackson, David; Jamshidi, Yalda; Jewell, David; Chris, Joyce; Kaye, Jane; Keane, Thomas; Kemp, John; Kennedy, Karen; Kent, Alastair; Kolb-Kokocinski, Anja; Lachance, Genevieve; Langford, Cordelia; Lee, Irene; Li, Rui; Li, Yingrui; Ryan, Liu; Lönnqvist, Jouko; Lopes, Margarida; MacArthur, Daniel G.; Massimo, Mangino; Marchini, Jonathan; Maslen, John; McCarthy, Shane; McGuffin, Peter; McIntosh, Andrew; McKechanie, Andrew; McQuillin, Andrew; Memari, Yasin; Metrustry, Sarah; Min, Josine; Moayyeri, Alireza; Morris, James; Muddyman, Dawn; Muntoni, Francesco; Northstone, Kate; O'Donovan, Michael; O'Rahilly, Stephen; Onoufriadis, Alexandros; Oualkacha, Karim; Owen, Michael; Palotie, Aarno; Panoutsopoulou, Kalliope; Parker, Victoria; Parr, Jeremy; Paternoster, Lavinia; Paunio, Tiina; Payne, Felicity; Perry, John; Pietilainen, Olli; Plagnol, Vincent; Quail, Michael A.; Quaye, Lydia; Raymond, Lucy; Rehnström, Karola; Brent Richards, J.; Ring, Sue; Ritchie, Graham R S; Savage, David B.; Schoenmakers, Nadia; Semple, Robert K.; Serra, Eva; Shihab, Hashem; Shin, So-Youn; Skuse, David; Small, Kerrin; Smee, Carol; Soler, Artigas María; Soranzo, Nicole; Southam, Lorraine; Spector, Tim; St Pourcain, Beate; St. Clair, David; Stalker, Jim; Surdulescu, Gabriela; Suvisaari, Jaana; Tachmazidou, Ioanna; Tian, Jing; Timpson, Nic; Tobin, Martin; Valdes, Ana; van Kogelenberg, Margriet; Vijayarangakannan, Parthiban; Wain, Louise; Walter, Klaudia; Wang, Jun; Ward, Kirsten; Wheeler, Ellie; Whittall, Ros; Williams, Hywel; Williamson, Kathy; Wilson, Scott G.; Wong, Kim; Whyte, Tamieka; ChangJiang, Xu; Zeggini, Eleftheria; Zhang, Feng; Zheng, Hou-Feng
The analysis of individuals with ciliary chondrodysplasias can shed light on sensitive mechanisms controlling ciliogenesis and cell signalling that are essential to embryonic development and survival. Here we identify TCTEX1D2 mutations causing Jeune asphyxiating thoracic dystrophy with partially penetrant inheritance. Loss of TCTEX1D2 impairs retrograde intraflagellar transport (IFT) in humans and the protist Chlamydomonas, accompanied by destabilization of the retrograde IFT dynein motor. We thus define TCTEX1D2 as an integral component of the evolutionarily conserved retrograde IFT machinery. In complex with several IFT dynein light chains, it is required for correct vertebrate skeletal formation but may be functionally redundant under certain conditions. PMID:26044572
CD1d and invariant NKT cells at the human maternal–fetal interface
Boyson, Jonathan E.; Rybalov, Basya; Koopman, Louise A.; Exley, Mark; Balk, Steven P.; Racke, Frederick K.; Schatz, Frederick; Masch, Rachel; Wilson, S. Brian; Strominger, Jack L.
Invariant CD1d-restricted natural killer T (iNKT) cells comprise a small, but significant, immunoregulatory T cell subset. Here, the presence of these cells and their CD1d ligand at the human maternal–fetal interface was investigated. Immunohistochemical staining of human decidua revealed the expression of CD1d on both villous and extravillous trophoblasts, the fetal cells that invade the maternal decidua. Decidual iNKT cells comprised 0.48% of the decidual CD3+ T cell population, a frequency...
Correlation between inter-spin interaction and molecular dynamics of organic radicals in organic 1D nanochannels
Energy Technology Data Exchange (ETDEWEB)
Kobayashi, Hirokazu [Department of Chemistry, College of Humanities and Sciences, Nihon University 3-25-40, Sakura-jo-sui, Setagaya-ku, Tokyo, 156-8550 (Japan)
One-dimensional (1D) molecular chains of 4-substituted-2,2,6,6-tetramethyl-1-piperidinyloxyl (4-X-TEMPO) radicals were constructed in the crystalline 1D nanochannels of 2,4,6-tris(4-chlorophenoxy)-1,3,5-triazine (CLPOT) used as a template. The ESR spectra of CLPOT inclusion compounds (ICs) using 4-X-TEMPO were examined on the basis of spectral simulation using EasySpin program package for simulating and fitting ESR spectra. The ESR spectra of [(CLPOT){sub 2}-(TEMPO){sub 1.0}] IC were isotropic in the total range of temperatures. The peak-to-peak line width (ΔB{sub pp}) became monotonically narrower from 2.8 to 1.3 mT with increase in temperature in the range of 4.2–298 K. The effect of the rotational diffusion motion of TEMPO radicals in the CLPOT nanochannels for the inter-spin interaction of the [(CLPOT){sub 2}-(TEMPO){sub 1.0}] IC was found to be smaller than the case of [(TPP){sub 2}−(TEMPO){sub 1.0}] IC (TPP = tris(o-phenylenedioxy)cyclotriphosphazene) reported in our previous study. The ΔB{sub pp} of the [(CLPOT){sub 2}-(TEMPO){sub 1.0}] IC in the whole range of temperatures was much narrower than the estimation to be based on the Van Vleck's formula for the second moment of the rigid lattice model where the electron spin can be considered as fixed; 11 mT of Gaussian line-width component. This suggests the possibility of exchange narrowing in the 1D organic-radical chains of the [(CLPOT){sub 2}-(TEMPO){sub 1.0}] IC. On the other hand, the ESR spectra of [(CLPOT){sub 2}-(MeO-TEMPO){sub 0.41}] IC (MeO-TEMPO = 4-methoxy-TEMPO) were reproduced by a superposition of major broad isotropic adsorption line and minor temperature-dependent modulated triplet component. This suggests that the IC has the part of 1D organic-radical chains and MeO-TEMPO molecules isolated in the CLPOT nanochannels.
Correlation between inter-spin interaction and molecular dynamics of organic radicals in organic 1D nanochannels
Kobayashi, Hirokazu
One-dimensional (1D) molecular chains of 4-substituted-2,2,6,6-tetramethyl-1-piperidinyloxyl (4-X-TEMPO) radicals were constructed in the crystalline 1D nanochannels of 2,4,6-tris(4-chlorophenoxy)-1,3,5-triazine (CLPOT) used as a template. The ESR spectra of CLPOT inclusion compounds (ICs) using 4-X-TEMPO were examined on the basis of spectral simulation using EasySpin program package for simulating and fitting ESR spectra. The ESR spectra of [(CLPOT)2-(TEMPO)1.0] IC were isotropic in the total range of temperatures. The peak-to-peak line width (ΔBpp) became monotonically narrower from 2.8 to 1.3 mT with increase in temperature in the range of 4.2-298 K. The effect of the rotational diffusion motion of TEMPO radicals in the CLPOT nanochannels for the inter-spin interaction of the [(CLPOT)2-(TEMPO)1.0] IC was found to be smaller than the case of [(TPP)2-(TEMPO)1.0] IC (TPP = tris(o-phenylenedioxy)cyclotriphosphazene) reported in our previous study. The ΔBpp of the [(CLPOT)2-(TEMPO)1.0] IC in the whole range of temperatures was much narrower than the estimation to be based on the Van Vleck's formula for the second moment of the rigid lattice model where the electron spin can be considered as fixed; 11 mT of Gaussian line-width component. This suggests the possibility of exchange narrowing in the 1D organic-radical chains of the [(CLPOT)2-(TEMPO)1.0] IC. On the other hand, the ESR spectra of [(CLPOT)2-(MeO-TEMPO)0.41] IC (MeO-TEMPO = 4-methoxy-TEMPO) were reproduced by a superposition of major broad isotropic adsorption line and minor temperature-dependent modulated triplet component. This suggests that the IC has the part of 1D organic-radical chains and MeO-TEMPO molecules isolated in the CLPOT nanochannels.
Ubiquitination and degradation of the hominoid-specific oncoprotein TBC1D3 is regulated by protein palmitoylation
Energy Technology Data Exchange (ETDEWEB)
Kong, Chen; Lange, Jeffrey J.; Samovski, Dmitri [Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110 (United States); Su, Xiong [Department of Internal Medicine, Center for Human Nutrition Washington University School of Medicine, St. Louis, MO 63110 (United States); Liu, Jialiu [Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110 (United States); Sundaresan, Sinju [Department of Internal Medicine, Center for Human Nutrition Washington University School of Medicine, St. Louis, MO 63110 (United States); Stahl, Philip D., E-mail: firstname.lastname@example.com [Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110 (United States)
Highlights: •Hominoid-specific oncogene TBC1D3 is targeted to plasma membrane by palmitoylation. •TBC1D3 is palmitoylated on two cysteine residues: 318 and 325. •TBC1D3 palmitoylation governs growth factors-induced TBC1D3 degradation. •Post-translational modifications may regulate oncogenic properties of TBC1D3. -- Abstract: Expression of the hominoid-specific oncoprotein TBC1D3 promotes enhanced cell growth and proliferation by increased activation of signal transduction through several growth factors. Recently we documented the role of CUL7 E3 ligase in growth factors-induced ubiquitination and degradation of TBC1D3. Here we expanded our study to discover additional molecular mechanisms that control TBC1D3 protein turnover. We report that TBC1D3 is palmitoylated on two cysteine residues: 318 and 325. The expression of double palmitoylation mutant TBC1D3:C318/325S resulted in protein mislocalization and enhanced growth factors-induced TBC1D3 degradation. Moreover, ubiquitination of TBC1D3 via CUL7 E3 ligase complex was increased by mutating the palmitoylation sites, suggesting that depalmitoylation of TBC1D3 makes the protein more available for ubiquitination and degradation. The results reported here provide novel insights into the molecular mechanisms that govern TBC1D3 protein degradation. Dysregulation of these mechanisms in vivo could potentially result in aberrant TBC1D3 expression and promote oncogenesis.
Nonconstant Positive Steady States and Pattern Formation of 1D Prey-Taxis Systems
Wang, Qi; Song, Yang; Shao, Lingjie
Prey-taxis is the process that predators move preferentially toward patches with highest density of prey. It is well known to have an important role in biological control and the maintenance of biodiversity. To model the coexistence and spatial distributions of predator and prey species, this paper concerns nonconstant positive steady states of a wide class of prey-taxis systems with general functional responses over 1D domain. Linearized stability of the positive equilibrium is analyzed to show that prey-taxis destabilizes prey-predator homogeneity when prey repulsion (e.g., due to volume-filling effect in predator species or group defense in prey species) is present, and prey-taxis stabilizes the homogeneity otherwise. Then, we investigate the existence and stability of nonconstant positive steady states to the system through rigorous bifurcation analysis. Moreover, we provide detailed and thorough calculations to determine properties such as pitchfork and turning direction of the local branches. Our stability results also provide a stable wave mode selection mechanism for thee reaction-advection-diffusion systems including prey-taxis models considered in this paper. Finally, we provide numerical studies of prey-taxis systems with Holling-Tanner kinetics to illustrate and support our theoretical findings. Our numerical simulations demonstrate that the 2× 2 prey-taxis system is able to model the formation and evolution of various striking patterns, such as spikes, periodic oscillations, and coarsening even when the domain is one-dimensional. These dynamics can model the coexistence and spatial distributions of interacting prey and predator species. We also give some insights on how system parameters influence pattern formation in these models.
Influence of lipid rafts on CD1d presentation by dendritic cells
DEFF Research Database (Denmark)
Peng, Wei; Martaresche, Cecile; Escande-Beillard, Nathalie;
information on lipid rafts in plasma membranes and allows a dynamics follow-up of lipid rafts partitioning. Using this method, we showed that CD1d plasma membrane expression was sensitive to low concentrations of detergent. This may suggest either that CD1d is associated with lipid rafts mainly...... in intracellular membranes or that its association with the lipid rafts in the plasma membrane is weak....... corresponding to lipid rafts and we describe that alpha-GalCer enhanced CD1d amount in the low density detergent insoluble fraction. We conclude that the membrane environment of CD1d can influence antigen presentation mainly when the endocytic pathway is required. Flow cytometry analysis can provide additional...
TCTEX1D2 mutations underlie Jeune asphyxiating thoracic dystrophy with impaired retrograde intraflagellar transport
Kayserili Karabey, Hülya; Schmidts, Miriam; Hou, Yuqing; Cortes, Claudio R.; Mans, Dorus A.; Huber, Celine; Boldt, Karsten; Patel, Mitali; van Reeuwijk, Jeroen; Plaza, Jean-Marc; van Beersum, Sylvia E. C.; Yap, Zhi Min; Letteboer, Stef J. F.; Taylor, S. Paige; Herridge, Warren; Johnson, Colin A.; Scambler, Peter J.; Ueffing, Marius; Krakow, Deborah; King, Stephen M.; Beales, Philip L.; Al-Gazali, Lihadh; Wicking, Carol; Cormier-Daire, Valerie; Roepman, Ronald; Mitchison, Hannah M.; Witman, George B.
The analysis of individuals with ciliary chondrodysplasias can shed light on sensitive mechanisms controlling ciliogenesis and cell signalling that are essential to embryonic development and survival. Here we identify TCTEX1D2 mutations causing Jeune asphyxiating thoracic dystrophy with partially penetrant inheritance. Loss of TCTEX1D2 impairs retrograde intraflagellar transport (IFT) in humans and the protist Chlamydomonas, accompanied by destabilization of the retrograde IFT dynein motor. W...
Protective mucosal immunity mediated by epithelial CD1d and IL-10.
Olszak, Torsten; Neves, Joana F; Dowds, C Marie; Baker, Kristi; Glickman, Jonathan; Davidson, Nicholas O; Lin, Chyuan-Sheng; Jobin, Christian; Brand, Stephan; Sotlar, Karl; Wada, Koichiro; Katayama, Kazufumi; Nakajima, Atsushi; Mizuguchi, Hiroyuki; Kawasaki, Kunito; Nagata, Kazuhiro; Müller, Werner; Snapper, Scott B; Schreiber, Stefan; Kaser, Arthur; Zeissig, Sebastian; Blumberg, Richard S
The mechanisms by which mucosal homeostasis is maintained are of central importance to inflammatory bowel disease. Critical to these processes is the intestinal epithelial cell (IEC), which regulates immune responses at the interface between the commensal microbiota and the host. CD1d presents self and microbial lipid antigens to natural killer T (NKT) cells, which are involved in the pathogenesis of colitis in animal models and human inflammatory bowel disease. As CD1d crosslinking on model IECs results in the production of the important regulatory cytokine interleukin (IL)-10 (ref. 9), decreased epithelial CD1d expression--as observed in inflammatory bowel disease--may contribute substantially to intestinal inflammation. Here we show in mice that whereas bone-marrow-derived CD1d signals contribute to NKT-cell-mediated intestinal inflammation, engagement of epithelial CD1d elicits protective effects through the activation of STAT3 and STAT3-dependent transcription of IL-10, heat shock protein 110 (HSP110; also known as HSP105), and CD1d itself. All of these epithelial elements are critically involved in controlling CD1d-mediated intestinal inflammation. This is demonstrated by severe NKT-cell-mediated colitis upon IEC-specific deletion of IL-10, CD1d, and its critical regulator microsomal triglyceride transfer protein (MTP), as well as deletion of HSP110 in the radioresistant compartment. Our studies thus uncover a novel pathway of IEC-dependent regulation of mucosal homeostasis and highlight a critical role of IL-10 in the intestinal epithelium, with broad implications for diseases such as inflammatory bowel disease. PMID:24717441
Protective mucosal immunity mediated by epithelial CD1d and IL-10
Olszak, Torsten; Neves, Joana F.; Dowds, C. Marie; Baker, Kristi; Glickman, Jonathan; Davidson, Nicholas O; Lin, Chyuan-Sheng; Jobin, Christian; Brand, Stephan; Sotlar, Karl; Wada, Koichiro; Katayama, Kazufumi; Nakajima, Atsushi; Mizuguchi, Hiroyuki; Kawasaki, Kunito
The mechanisms by which mucosal homeostasis is maintained are of central importance to inflammatory bowel disease. Critical to these processes is the intestinal epithelial cell (IEC), which regulates immune responses at the interface between the commensal microbiota and the host1,2. CD1d presents self and microbial lipid antigens to natural killer T (NKT) cells, which are involved in the pathogenesis of colitis in animal models and human inflammatory bowel disease3–8. As CD1d crosslinking on ...
Optimization of a cyclic peptide inhibitor of Ser/Thr phosphatase PPM1D (Wip1).
Hayashi, Ryo; Tanoue, Kan; Durell, Stewart R; Chatterjee, Deb K; Jenkins, Lisa M Miller; Appella, Daniel H; Appella, Ettore
PPM1D (PP2Cδ or Wip1) was identified as a wild-type p53-induced Ser/Thr phosphatase that accumulates after DNA damage and classified into the PP2C family. It dephosphorylates and inactivates several proteins critical for cellular stress responses, including p38 MAPK, p53, and ATM. Furthermore, PPM1D is amplified and/or overexpressed in a number of human cancers. Thus, inhibition of its activity could constitute an important new strategy for therapeutic intervention to halt the progression of several different cancers. Previously, we reported the development of a cyclic thioether peptide with low micromolar inhibitory activity toward PPM1D. Here, we describe important improvements in the inhibitory activity of this class of cyclic peptides and also present a binding model based upon the results. We found that specific interaction of an aromatic ring at the X1 position and negative charge at the X5 and X6 positions significantly increased the inhibitory activity of the cyclic peptide, with the optimized molecule having a K(i) of 110 nM. To the best of our knowledge, this represents the highest inhibitory activity reported for an inhibitor of PPM1D. We further developed an inhibitor selective for PPM1D over PPM1A with a K(i) of 2.9 μM. Optimization of the cyclic peptide and mutagenesis experiments suggest that a highly basic loop unique to PPM1D is related to substrate specificity. We propose a new model for the catalytic site of PPM1D and inhibition by the cyclic peptides that will be useful both for the subsequent design of PPM1D inhibitors and for identification of new substrates. PMID:21528848
One-Dimensional (1D) ZnS Nanomaterials and Nanostructures
Institute of Scientific and Technical Information of China (English)
Xiaosheng FANG; Lide ZHANG
One-dimensional (1D) nanomaterials and nanostructures have received much attention due to their potential interest for understanding fundamental physical concepts and for applications in constructing nanoscale electric and optoelectronic devices. Zinc sulfide (ZnS) is an important semiconductor compound of Ⅱ-Ⅵ group,and the synthesis of 1D ZnS nanomaterials and nanostructures has been of growing interest owing to their promising application in nanoscale optoelectronic devices. This paper reviews the recent progress on 1D ZnS nanomaterials and nanostructures, including nanowires, nanowire arrays, nanorods, nanobelts or nanoribbons,nanocables, and hierarchical nanostructures etc. This article begins with a survey of various methods that have been developed for generating 1D nanomaterials and nanostructures, and then mainly focuses on structures,synthesis, characterization, formation mechanisms and optical property tuning, and luminescence mechanisms of 1D ZnS nanomaterials and nanostructures. Finally, this review concludes with personal views towards future research on 1D ZnS nanomaterials and nanostructures.
HERMES Precision Results on g1p, g1d and g1n and the First Measurement of the Tensor Structure Function b1d
Riedl, C; Akopov, Z; Amarian, M; Ammosov, V V; Andrus, A; Aschenauer, E C; Augustyniak, W; Avakian, R; Avetisian, A; Avetissian, E; Bailey, P; Baturin, V; Baumgarten, C; Beckmann, M; Belostotskii, S; Bernreuther, S; Bianchi, N; Blok, H P; Böttcher, Helmut B; Borisov, A; Bouwhuis, M; Brack, J; Brüll, A; Bryzgalov, V V; Capitani, G P; Chiang, H C; Ciullo, G; Contalbrigo, M; Dalpiaz, P F; De Leo, R; De Nardo, L; De Sanctis, E; Devitsin, E G; Di Nezza, P; Düren, M; Ehrenfried, M; Elalaoui-Moulay, A; Elbakian, G M; Ellinghaus, F; Elschenbroich, U; Ely, J; Fabbri, R; Fantoni, A; Feshchenko, A; Felawka, L; Fox, B; Franz, J; Frullani, S; Gärber, Y; Gapienko, G; Gapienko, V; Garibaldi, F; Garrow, K; Garutti, E; Gaskell, D; Gavrilov, G E; Karibian, V; Graw, G; Grebenyuk, O; Greeniaus, L G; Hafidi, K; Hartig, M; Hasch, D; Heesbeen, D; Henoch, M; Hertenberger, R; Hesselink, W H A; Hillenbrand, A; Hoek, M; Holler, Y; Hommez, B; Iarygin, G; Ivanilov, A; Izotov, A; Jackson, H E; Jgoun, A; Kaiser, R; Kinney, E; Kiselev, A; Königsmann, K C; Kopytin, M; Korotkov, V A; Kozlov, V; Krauss, B; Krivokhizhin, V G; Lagamba, L; Lapikas, L; Laziev, A; Lenisa, P; Liebing, P; Lindemann, T; Lipka, K; Lorenzon, W; Lü, J; Maiheu, B; Makins, N C R; Marianski, B; Marukyan, H O; Masoli, F; Mexner, V; Meyners, N; Miklukho, O; Miller, C A; Miyachi, Y; Muccifora, V; Nagaitsev, A; Nappi, E; Naryshkin, Yu; Nass, A; Negodaev, M A; Nowak, Wolf-Dieter; Oganessyan, K; Ohsuga, H; Orlandi, G; Pickert, N; Potashov, S Yu; Potterveld, D H; Raithel, M; Reggiani, D; Reimer, P E; Reischl, A; Reolon, A R; Rith, K; Airapetian, A; Rosner, G; Rostomyan, A; Rubacek, L; Ryckbosch, D; Salomatin, Yu I; Sanjiev, I; Savin, I; Scarlett, C; Schäfer, A; Schill, C; Schnell, G; Schüler, K P; Schwind, A; Seele, J; Seidl, R; Seitz, B; Shanidze, R G; Shearer, C; Shibata, T A; Shutov, V B; Simani, M C; Sinram, K; Stancari, M D; Statera, M; Steffens, E; Steijger, J J M; Stewart, J; Stösslein, U; Tait, P; Tanaka, H; Taroian, S P; Tchuiko, B; Terkulov, A R; Tkabladze, A V; Trzcinski, A; Tytgat, M; Vandenbroucke, A; Van der Nat, P B; van der Steenhoven, G; Vetterli, Martin C; Vikhrov, V; Vincter, M G; Visser, J; Vogel, C; Vogt, M; Volmer, J; Weiskopf, C; Wendland, J; Wilbert, J; Ybeles-Smit, G V; Yen, S; Zihlmann, B; Zohrabyan, H G; Zupranski, P; Riedl, Caroline
Final HERMES results on the proton, deuteron and neutron structure function g1 are presented in the kinematic range 0.0021
Stable Interacting $(2 + 1)d$ Conformal Field Theories at the Boundary of a class of $(3 + 1)d$ Symmetry Protected Topological Phases
Bi, Zhen; BenTov, Yoni; Xu, Cenke
Motivated by recent studies of symmetry protected topological (SPT) phases, we explore the possible gapless quantum disordered phases in the $(2+1)d$ nonlinear sigma model defined on the Grassmannian manifold $\\frac{U(N)}{U(n)\\times U(N - n)}$ with a Wess-Zumino-Witten (WZW) term at level $k$, which is the effective low energy field theory of the boundary of certain $(3+1)d$ SPT states. With $k = 0$, this model has a well-controlled large-$N$ limit, $i.e.$ its renormalization group equations can be computed exactly with large-$N$. However, with the WZW term, the large-$N$ and large-$k$ limit alone is not sufficient for a reliable study of the nature of the quantum disordered phase. We demonstrate that at least for $n = 1$, through a combined large-$N$, large-$k$ and $3-\\epsilon$ generalization, a stable fixed point in the quantum disordered phase can be reliably located, which corresponds to a $(2+1)d$ strongly interacting conformal field theory. Extension of our method to $n > 1$ will also be discussed.
A 1-D Size Specific Numerical Model for Gravel Transport That Includes Sediment Exchange with a Floodplain
Lauer, Wesley; Viparelli, Enrica; Piegay, Herve
Sedimentary deposits adjacent to rivers can represent important sources and sinks for bed material sediment, particularly on decadal and longer timescales. The Morphodynamics and Sediment Tracers in 1-D model (MAST-1D) is a size-specific sediment transport model that allows for active exchange between channel and floodplain sediment on river reaches of tens to hundreds of kilometers in length. The model is intended to provide a mechanism for performing a first-order assessment of the likely importance of off-channel sediment exchange in controlling decadal-scale geomorphic trends, thereby helping plan and/or prioritize field data collection and higher resolution modeling work. The model develops a sediment budget for short segments of an alluvial valley. Each segment encompasses several active river bends. In each segment, a sediment transport capacity computation is performed to determine the downstream flux of bed material sediment, following the approach of most other 1-D sediment transport models. However, the model differs from most other bed evolution models in that sediment can be exchanged with the floodplain in each segment, and mass conservation is applied to both the active layer and floodplain sediment storage reservoirs. The potential for net imbalances in overall exchange as well as the size specific nature of the computations allows the model to simulate reach-scale aggradation/degradation and/or changes in bed texture. The inclusion of fine sediment in the model allows it to track geochemical tracer material and also provides a mechanism to simulate, to first order, the effects of changes in the supply of silt and clay on overall channel hydraulic capacity. The model is applied to a ~40 km reach of the Ain River, a tributary of the Rhône River in eastern France that has experienced a significant sediment deficit as a result of the construction of several dams between 1920 and 1970. MAST-1D simulations result in both incision and the formation of a
Benchmarks and models for 1-D radiation transport in stochastic participating media
Energy Technology Data Exchange (ETDEWEB)
Miller, D S
Benchmark calculations for radiation transport coupled to a material temperature equation in a 1-D slab and 1-D spherical geometry binary random media are presented. The mixing statistics are taken to be homogeneous Markov statistics in the 1-D slab but only approximately Markov statistics in the 1-D sphere. The material chunk sizes are described by Poisson distribution functions. The material opacities are first taken to be constant and then allowed to vary as a strong function of material temperature. Benchmark values and variances for time evolution of the ensemble average of material temperature energy density and radiation transmission are computed via a Monte Carlo type method. These benchmarks are used as a basis for comparison with three other approximate methods of solution. One of these approximate methods is simple atomic mix. The second approximate model is an adaptation of what is commonly called the Levermore-Pomraning model and which is referred to here as the standard model. It is shown that recasting the temperature coupling as a type of effective scattering can be useful in formulating the third approximate model, an adaptation of a model due to Su and Pomraning which attempts to account for the effects of scattering in a stochastic context. This last adaptation shows consistent improvement over both the atomic mix and standard models when used in the 1-D slab geometry but shows limited improvement in the 1-D spherical geometry. Benchmark values are also computed for radiation transmission from the 1-D sphere without material heating present. This is to evaluate the performance of the standard model on this geometry--something which has never been done before. All of the various tests demonstrate the importance of stochastic structure on the solution. Also demonstrated are the range of usefulness and limitations of a simple atomic mix formulation.
Using 1D theory to understand 3D stagnation of a wire-array Z pinch in the absence of radiation
Yu, Edmund
Many high-energy-density systems implode towards the axis of symmetry, where it collides on itself, forming a hot plasma. However, experiments show these imploding plasmas develop three-dimensional (3D) structures. As a result, the plasma cannot completely dissipate its kinetic energy at stagnation, instead retaining significant 3D flow. A useful tool for understanding the effects of this residual flow is 3D simulation, but the amount and complexity of information can be daunting. To address this problem, we explore the connection between 3D simulation and one-dimensional (1D) theory. Such a connection, if it exists, is mutually beneficial: 1D theory can provide a clear picture of the underlying dynamics of 3D stagnation. On the other hand, deviations between theory and simulation suggest how 1D theory must be modified to account for 3D effects. In this work, we focus on a 3D, magnetohydrodynamic simulation of a compact wire-array Z pinch. To provide a simpler background against which to test our ideas, we artificially turn off radiation during the stagnation phase. Examination of the initial accumulation of mass on axis reveals oblique collision between jets, shock accretion, and vortex formation. Despite evidence for shock-dominated stagnation, a 1D shockless stagnation solution is more appropriate for describing the global dynamics, in that it reproduces the increase of on-axis density with time. However, the 1D solution must be modified to account for 3D effects: the flows suggest enhanced thermal transport as well as centrifugal force. Upon reaching peak compression, the stagnation transitions to a second phase, in which the high-pressure core on axis expands outward into the remaining imploding plasma. During this phase, a 1D shock solution describes the growth of the shock accretion region, as well as the decrease of on-axis density with time. However, the effect of 3D flows is still present: the on-axis temperature does not cool during expansion, which
1D and 2D Numerical Modeling for Solving Dam-Break Flow Problems Using Finite Volume Method
Directory of Open Access Journals (Sweden)
Szu-Hsien Peng
Full Text Available The purpose of this study is to model the flow movement in an idealized dam-break configuration. One-dimensional and two-dimensional motion of a shallow flow over a rigid inclined bed is considered. The resulting shallow water equations are solved by finite volumes using the Roe and HLL schemes. At first, the one-dimensional model is considered in the development process. With conservative finite volume method, splitting is applied to manage the combination of hyperbolic term and source term of the shallow water equation and then to promote 1D to 2D. The simulations are validated by the comparison with flume experiments. Unsteady dam-break flow movement is found to be reasonably well captured by the model. The proposed concept could be further developed to the numerical calculation of non-Newtonian fluid or multilayers fluid flow.
Giant fluctuations of local magnetoresistance of organic spin valves and the non-Hermitian 1D Anderson model.
Roundy, R C; Nemirovsky, D; Kagalovsky, V; Raikh, M E
Motivated by recent experiments, where the tunnel magnetoresitance (TMR) of a spin valve was measured locally, we theoretically study the distribution of TMR along the surface of magnetized electrodes. We show that, even in the absence of interfacial effects (like hybridization due to donor and acceptor molecules), this distribution is very broad, and the portion of area with negative TMR is appreciable even if on average the TMR is positive. The origin of the local sign reversal is quantum interference of subsequent spin-rotation amplitudes in the course of incoherent transport of carriers between the source and the drain. We find the distribution of local TMR exactly by drawing upon formal similarity between evolution of spinors in time and of the reflection coefficient along a 1D chain in the Anderson model. The results obtained are confirmed by the numerical simulations. PMID:24949781
A Mathematical Model of T1D Acceleration and Delay by Viral Infection.
Moore, James R; Adler, Fred
Type 1 diabetes (T1D) is often triggered by a viral infection, but the T1D prevalence is rising among populations that have a lower exposure to viral infection. In an animal model of T1D, the NOD mouse, viral infection at different ages may either accelerate or delay disease depending on the age of infection and the type of virus. Viral infection may affect the progression of T1D via multiple mechanisms: triggering inflammation, bystander activation of self-reactive T-cells, inducing a competitive immune response, or inducing a regulatory immune response. In this paper, we create mathematical models of the interaction of viral infection with T1D progression, incorporating each of these four mechanisms. Our goal is to understand how each viral mechanism interacts with the age of infection. The model predicts that each viral mechanism has a unique pattern of interaction with disease progression. Viral inflammation always accelerates disease, but the effect decreases with age of infection. Bystander activation has little effect at younger ages and actually decreases incidence at later ages while accelerating disease in mice that do get the disease. A competitive immune response to infection can decrease incidence at young ages and increase it at older ages, with the effect decreasing over time. Finally, an induced Treg response decreases incidence at any age of infection, but the effect decreases with age. Some of these patterns resemble those seen experimentally. PMID:27030351
Deconvolution of Complex 1D NMR Spectra Using Objective Model Selection.
Directory of Open Access Journals (Sweden)
Travis S Hughes
Full Text Available Fluorine (19F NMR has emerged as a useful tool for characterization of slow dynamics in 19F-labeled proteins. One-dimensional (1D 19F NMR spectra of proteins can be broad, irregular and complex, due to exchange of probe nuclei between distinct electrostatic environments; and therefore cannot be deconvoluted and analyzed in an objective way using currently available software. We have developed a Python-based deconvolution program, decon1d, which uses Bayesian information criteria (BIC to objectively determine which model (number of peaks would most likely produce the experimentally obtained data. The method also allows for fitting of intermediate exchange spectra, which is not supported by current software in the absence of a specific kinetic model. In current methods, determination of the deconvolution model best supported by the data is done manually through comparison of residual error values, which can be time consuming and requires model selection by the user. In contrast, the BIC method used by decond1d provides a quantitative method for model comparison that penalizes for model complexity helping to prevent over-fitting of the data and allows identification of the most parsimonious model. The decon1d program is freely available as a downloadable Python script at the project website (https://github.com/hughests/decon1d/.
Possible Dimensional Crossover to 1D of ^3He Fluid in Nanochannels Observed in Susceptibilities
Matsushita, Taku; Kurebayashi, Katsuya; Shibatsuji, Ryosuke; Hieda, Mitsunori; Wada, Nobuo
Dimensional crossover to the one-dimensional (1D) state from higher dimensions has been studied for dilute ^3He fluid adsorbed in 2.4 nm ^4He-preplated nanochannels, by susceptibility measurements down to 70 mK using 4.29 MHz nuclear magnetic resonance. In nanochannels, since energy states of ^3He motion perpendicular to the channel axis are discrete, a genuine 1D ^3He fluid is expected when the Fermi energy is less than the first excitation Δ _{01} for azimuthal motion. The susceptibilities χ above 0.3 K show the Curie-law susceptibilities independent of the ^3He density, which are characteristic of nondegenerate fluid in higher dimensions. With decreasing the temperature, a significant reduction of χ T was observed from about 0.3 K for all ^3He densities. It is considered to be due to the dimensional crossover below Δ _{01}˜ 0.5 K to the 1D ^3He state in the semi-degenerate regime above the Fermi temperature. In the 1D state at lower temperatures, T-independent χ were observed for ^3He of 0.019 layers below 0.1 K. It suggests that the 1D ^3He fluid enters the quantum degenerate regime.
An energy- and charge-conserving, nonlinearly implicit, electromagnetic 1D-3V Vlasov-Darwin particle-in-cell algorithm
Chen, Guangye
A recent proof-of-principle study proposes a nonlinear electrostatic implicit particle-in-cell (PIC) algorithm in one dimension (Chen, Chacon, Barnes, J. Comput. Phys. 230 (2011) 7018). The algorithm employs a kinetically enslaved Jacobian-free Newton-Krylov (JFNK) method, and conserves energy and charge to numerical round-off. In this study, we generalize the method to electromagnetic simulations in 1D using the Darwin approximation of Maxwell's equations, which avoids radiative aliasing noise issues by ordering out the light wave. An implicit, orbit-averaged time-space-centered finite difference scheme is applied to both the 1D Darwin field equations (in potential form) and the 1D-3V particle orbit equations to produce a discrete system that remains exactly charge- and energy-conserving. Furthermore, enabled by the implicit Darwin equations, exact conservation of the canonical momentum per particle in any ignorable direction is enforced via a suitable scattering rule for the magnetic field. Several 1D numer...
Sensitivity studies of the recent new data on O(1D quantum yields in O3 Hartley band photolysis in the stratosphere
Directory of Open Access Journals (Sweden)
N. Taniguchi
Full Text Available The production yields of excited oxygen O(1D atoms from the near ultraviolet O3 photolysis are essential quantities for atmospheric chemistry calculations because of its importance as major sources of hydroxyl (OH radicals and nitric oxide (NO. Recently, new O(1D quantum yields from O3 photolysis between 230 and 305 nm in the Hartley band region were reported, which are almost independent of the photolysis wavelength (0.88-0.93 and smaller than NASA/JPL-2000 recommendations (0.95 between 240 and 300 nm. In order to assess consequences of the new data of O(1D quantum yields on the stratospheric chemistry, the changes in stratospheric chemical partitioning and O3 concentration are examined using a one-dimensional atmospheric model. Our steady state model simulations for 40° N in March indicate that the smaller O(1D quantum yields result in increases of stratospheric O3 (up to ~2% in the upper stratosphere, which are attributed to the changes in HOx, NOx, and ClOx abundance and their catalyzed O3 loss rates.
Transparent Conducting Electrodes based on 1D and 2D Ag Nanogratings for Organic Photovoltaics
Zeng, Beibei; Bartoli, Filbert J
The optical and electrical properties of optically-thin one-dimensional (1D) Ag nanogratings and two-dimensional (2D) Ag nanogrids are studied, and their use as transparent electrodes in organic photovoltaics are explored. A large broadband and polarization-insensitive optical absorption enhancement in the organic light-harvesting layers is theoretically and numerically demonstrated using either single-layer 2D Ag nanogrids or two perpendicular 1D Ag nanogratings, and is attributed to the excitation of surface plasmon resonances and plasmonic cavity modes. Total photon absorption enhancements of 150% and 200% are achieved for the optimized single-layer 2D Ag nanogrids and double (top and bottom) perpendicular 1D Ag nanogratings, respectively.
Institute of Scientific and Technical Information of China (English)
MU Jin-bin; ZHANG Xiao-feng
A real-time forecasting method coupled with the 1-D unsteady flow model with the recursive least-square method was developed. The 1-D unsteady flow model was modified by using the time-variant parameter and revising it dynamically through introducing a variable weighted forgetting factor, such that the output of the model could be adjusted for the real time forecasting of floods. The application of the new real time forecasting model in the reach from Yichang to Luoshan of the Yangtze River was demonstrated. Computational result shows that the forecasting accuracy of the new model is much higher than that of the original 1-D unsteady flow model. The method developed is effective for flood forecasting, and can be used for practical operation in the flood forecasting.
3+1D Massless Weyl Spinors from Bosonic Scalar-Tensor Duality
Directory of Open Access Journals (Sweden)
Andrea Amoretti
Full Text Available We consider the fermionization of a bosonic-free theory characterized by the 3+1D scalar-tensor duality. This duality can be interpreted as the dimensional reduction, via a planar boundary, of the 4+1D topological BF theory. In this model, adopting the Sommerfield tomographic representation of quantized bosonic fields, we explicitly build a fermionic operator and its associated Klein factor such that it satisfies the correct anticommutation relations. Interestingly, we demonstrate that this operator satisfies the massless Dirac equation and that it can be identified with a 3+1D Weyl spinor. Finally, as an explicit example, we write the integrated charge density in terms of the tomographic transformed bosonic degrees of freedom.
Periodic Properties of 1D FE Discrete Models in High Frequency Dynamics
Directory of Open Access Journals (Sweden)
A. Żak
Full Text Available Finite element discrete models of various engineering 1D structures may be considered as structures of certain periodic characteristics. The source of this periodicity comes from the discontinuity of stress/strain field between the elements. This behaviour remains unnoticeable, when low frequency dynamics of these structures is investigated. At high frequency regimes, however, its influence may be strong enough to dominate calculated structural responses distorting or even falsifying them completely. In this paper, certain computational aspects of structural periodicity of 1D FE discrete models are discussed by the authors. In this discussion, the authors focus their attention on an exemplary problem of 1D rod modelled according to the elementary theory.
PC-1D installation manual and user's guide
Energy Technology Data Exchange (ETDEWEB)
Basore, P.A.
PC-1D is a software package for personal computers that uses finite-element analysis to solve the fully-coupled two-carrier semiconductor transport equations in one dimension. This program is particularly useful for analyzing the performance of optoelectronic devices such as solar cells, but can be applied to any bipolar device whose carrier flows are primarily one-dimensional. This User's Guide provides the information necessary to install PC-1D, define a problem for solution, solve the problem, and examine the results. Example problems are presented which illustrate these steps. The physical models and numerical methods utilized are presented in detail. This document supports version 3.1 of PC-1D, which incorporates faster numerical algorithms with better convergence properties than previous versions of the program. 51 refs., 17 figs., 5 tabs.
1-D Compression Behaviour of Acid Sulphate Soils Treated with Alkali-Activated Slag
Directory of Open Access Journals (Sweden)
Shahidul Islam
Full Text Available Improvements of soft soils by mechanically mixing cementitious additives have been widely practised for construction of infrastructure. Mixing of additives improves strength and compressibility properties of soils through the development of soil structure. This study investigates the 1-D compression behaviour of alkali-activated slag treated acid sulphate soils (ASS cured up to 365 days. The void ratio-logarithm of pressure (e-logσ′ behaviour of treated ASS, including the destructuration behaviour, with additive contents and curing time have been analysed. X-ray diffraction (XRD and scanning electron microscopy (SEM analyses have been undertaken to explain the observed variations of the 1-D compression behaviour. This paper presents the results of these analyses in view of obtaining an insight into the 1-D compression behaviour of treated ASS with the help of mineralogical analysis.
Solution to 1-D consolidation of non-homogeneous soft clay
Institute of Scientific and Technical Information of China (English)
XIE Kang-he; WEN Jie-bang; XIA Jian-zhong
In this work, semi-analytical methods were used to solve the problem of 1-D consolidation of non-homogeneous soft clay with spatially varying coefficients of permeability and compressibility. The semi-analytical solution was programmed and then verified by comparison with the obtained analytical solution of a special case. Based on the results of some computations and comparisons with the 1-D homogeneous consolidation (by Terzaghi) and the 1-D non-linear consolidation theory (by Davis et al.)of soft clay, some diagrams were prepared and the relevant consolidation behavior of non-homogeneous soils is discussed. It was shown that the result obtained differs greatly from Terzaghi's theory and that of the non-linear consolidation theory when the coefficients of permeability and compressibility vary greatly.
Regional airflow and particle distribution in the lung with a 3D-1D coupled subject-specific boundary condition
Choi, Jiwoong; Yin, Youbing; Hoffman, Eric; Tawhai, Merryn; Lin, Ching-Long
Correct prediction of regional distribution of inhaled aerosol particles is vital to improve pulmonary medicine. Physiologically consistent regional ventilations of airflow and aerosol particles are simulated with a 3D-1D coupled subject-specific boundary condition (BC). In 3D CT-resolved 7-generation airways, large eddy simulations are performed to capture detailed airflow characteristics and Lagrangian particle simulations are carried to track the particle transport and deposition. Results are compared with two traditional outlet BCs: uniform velocity and uniform pressure. Proposed BC is eligible for physiologically consistent airflow distribution in the lung, while the others are not. The regional ventilation and deposition of particles reflect the regional ventilation of airflow. In this study, two traditional BCs yield up to 98% (334%) over-prediction in lobar particle ventilation (deposition) fraction. Upper to lower particle ventilation ratios of both left and right lungs read ˜0.4 with the proposed BC, while those for the other two BCs vary with the error up to 73%.
1D Runoff-runon stochastic model in the light of queueing theory : heterogeneity and connectivity
Harel, M.-A.; Mouche, E.; Ledoux, E.
Runoff production on a hillslope during a rainfall event may be simplified as follows. Given a soil of constant infiltrability I, which is the maximum amount of water that the soil can infiltrate, and a constant rainfall intensity R, runoff is observed where R is greater than I. The infiltration rate equals the infiltrability when runoff is produced, R otherwise. When ponding time, topography, and overall spatial and temporal variations of physical parameters, such as R and I, are neglected, the runoff equation remains simple. In this study, we consider soils of spatially variable infiltrability. As runoff can re-infiltrate on down-slope areas of higher infiltrabilities (runon), the resulting process is highly non-linear. The stationary runoff equation is: Qn+1 = max(Qn + (R - In)*Δx , 0) where Qn is the runoff arriving on pixel n of size Δx [L2/T], R and In the rainfall intensity and infiltrability on that same pixel [L/T]. The non-linearity is due to the dependence of infiltration on R and Qn, that is runon. This re-infiltration process generates patterns of runoff along the slope, patterns that organise and connect to each other differently depending on the rainfall intensity and the nature of the soil heterogeneity. The runoff connectivity, assessed using the connectivity function of Allard (1993), affects greatly the dynamics of the runoff hillslope. Our aim is to assess, in a stochastic framework, the runoff organization on 1D slopes with random infiltrabilities (log-normal, exponential, bimodal and uniform distributions) by means of theoretical developments and numerical simulations. This means linking the nature of soil heterogeneity with the resulting runoff organisation. In term of connectivity, we investigate the relations between structural (infiltrability) and functional (runoff) connectivity. A theoretical framework based on the queueing theory is developed. We implement the idea of Jones et al. (2009), who remarked that the above formulation is
Modelling turbulent vertical mixing sensitivity using a 1-D version of NEMO
Directory of Open Access Journals (Sweden)
G. Reffray
Full Text Available Through two numerical experiments, a 1-D vertical model called NEMO1D was used to investigate physical and numerical turbulent-mixing behaviour. The results show that all the turbulent closures tested (k + l from Blanke and Delecluse, 1993 and two equation models: Generic Lengh Scale closures from Umlauf and Burchard, 2003 are able to correctly reproduce the classical test of Kato and Phillips (1969 under favourable numerical conditions while some solutions may diverge depending on the degradation of the spatial and time discretization. The performances of turbulence models were then compared with data measured over a one-year period (mid-2010 to mid-2011 at the PAPA station, located in the North Pacific Ocean. The modelled temperature and salinity were in good agreement with the observations, with a maximum temperature error between −2 and 2 °C during the stratified period (June to October. However the results also depend on the numerical conditions. The vertical RMSE varied, for different turbulent closures, from 0.1 to 0.3 °C during the stratified period and from 0.03 to 0.15 °C during the homogeneous period. This 1-D configuration at the PAPA station (called PAPA1D is now available in NEMO as a reference configuration including the input files and atmospheric forcing set described in this paper. Thus, all the results described can be recovered by downloading and launching PAPA1D. The configuration is described on the NEMO site (http://www.nemo-ocean.eu/Using-NEMO/Configurations/C1D_PAPA. This package is a good starting point for further investigation of vertical processes.
Carboxyl terminus-truncated α1D-adrenoceptors inhibit the ERK pathway.
Alfonzo-Méndez, Marco A; Castillo-Badillo, Jean A; Romero-Ávila, M Teresa; Rivera, Richard; Chun, Jerold; García-Sáinz, J Adolfo
Human α1D-adrenoceptors are G protein-coupled receptors that mediate adrenaline/noradrenaline actions. There is a growing interest in identifying regulatory domains in these receptors and determining how they function. In this work, we show that the absence of the human α1D-adrenoceptor carboxyl tail results in altered ERK (extracellular signal-regulated kinase) and p38 phosphorylation states. Amino terminus-truncated and both amino and carboxyl termini-truncated α1D-adrenoceptors were transfected into Rat-1, HEK293, and B103 cells, and changes in the phosphorylation state of extracellular signal-regulated kinase was assessed using biochemical and biophysical approaches. The phosphorylation state of other protein kinases (p38, MEK1, and Raf-1) was also studied. Noradrenaline-induced ERK phosphorylation in Rat-1 fibroblasts expressing amino termini-truncated α1D-adrenoceptors. However, in cells expressing receptors with both amino and carboxyl termini truncations, noradrenaline-induced activation was abrogated. Interestingly, ERK phosphorylation that normally occurs through activation of endogenous G protein-coupled receptors, EGF receptors, and protein kinase C, was also decreased, suggesting that downstream steps in the mitogen-activated protein kinase pathway were affected. A similar effect was observed in B103 cells but not in HEK 293 cells. Phosphorylation of Raf-1 and MEK1 was also diminished in Rat-1 fibroblasts expressing amino- and carboxyl-truncated α1D-adrenoceptors. Our data indicate that expression of carboxyl terminus-truncated α1D-adrenoceptors alters ERK and p38 phosphorylation state. PMID:27146292
Massive quantum vortex excitations in a pure gauge abelian theory in 2+1D
Marino, E C
We introduce and study a pure gauge abelian theory in 2+1D in which massive quantum vortex states do exist in the spectrum of excitations. This theory can be mapped in a three dimensional gas of point particles with a logarithmic interaction, in the grand-canonical ensemble. We claim that this theory is the 2+1D analog of the Sine-Gordon, the massive vortices being the counterparts of Sine-Gordon solitons. We show that a symmetry breaking, order parameter, similar to the vacuum expectation value of a Higgs field does exist.
Column Testing and 1D Reactive Transport Modeling to Evaluate Uranium Plume Persistence Processes
Energy Technology Data Exchange (ETDEWEB)
Johnson, Raymond H. [Navarro Research and Engineering, Inc.; Morrison, Stan [Navarro Research and Engineering, Inc.; Morris, Sarah [Navarro Research and Engineering, Inc.; Tigar, Aaron [Navarro Research and Engineering, Inc.; Dam, William [U.S. Department of Energy, Office of Legacy Management; Dayvault, Jalena [U.S. Department of Energy, Office of Legacy Management
Motivation for Study: Natural flushing of contaminants at various U.S. Department of Energy Office of Legacy Management sites is not proceeding as quickly as predicted (plume persistence) Objectives: Help determine natural flushing rates using column tests. Use 1D reactive transport modeling to better understand the major processes that are creating plume persistence Approach: Core samples from under a former mill tailings area Tailings have been removed. Column leaching using lab-prepared water similar to nearby Gunnison River water. 1D reactive transport modeling to evaluate processes
Refractive index sensor based on a 1D photonic crystal in a microfluidic channel
DEFF Research Database (Denmark)
Rodrigues de Sousa Nunes, Pedro André; Mortensen, Asger; Kutter, Jörg Peter;
A refractive index sensor has been fabricated in silicon oxynitride by standard UV lithography and dry etching processes. The refractive index sensor consists of a 1D photonic crystal (PhC) embedded in a microfluidic channel addressed by fiber-terminated planar waveguides. Experimental demonstrat......A refractive index sensor has been fabricated in silicon oxynitride by standard UV lithography and dry etching processes. The refractive index sensor consists of a 1D photonic crystal (PhC) embedded in a microfluidic channel addressed by fiber-terminated planar waveguides. Experimental...
Statistics of Eigenfunctions in 1D Tight Binding Model: Distribution of Riccati Variable
Institute of Scientific and Technical Information of China (English)
WANG Wen-Ge
For energy eigenfunctions in 1D tight binding model, the distribution of ratios of the nearest components (Riccati variable), denoted by f(p), gives information on their fluctuation properties. The shape of f(p) is studied numerically for three versions of the 1D tight binding model. It is shown that when perturbation is strong the shape of f(p) is usually quite close to that of the Lorentzian distribution and in the case of weak perturbation the shape of the central part of f(p) is model-dependent while the shape of tails are still close to the Lorentzian form.``
Characterization of 5-HT1D receptor binding sites in post-mortem human brain cortex.
Martial, J; de Montigny, C; Cecyre, D; Quirion, R
The present study provides further evidence for the presence of serotonin1D (5-HT1D) receptors in post-mortem human brain. Receptor binding parameters in temporal cortex homogenates were assessed using [3H]5-HT in the presence of 100 nM 8-OH-DPAT, 1 microM propranolol and 1 microM mesulergine to prevent labelling of the 5-HT1A, 5-HT1B and 5-HT1C sites, respectively. Under these conditions, [3H]5-HT apparently bound to a class of high affinity (Kd = 5.0 +/- 1.0 nM) low capacity (Bmax = 96 +/- ...
CD1d-restricted peripheral T cell lymphoma in mice and humans.
Bachy, Emmanuel; Urb, Mirjam; Chandra, Shilpi; Robinot, Rémy; Bricard, Gabriel; de Bernard, Simon; Traverse-Glehen, Alexandra; Gazzo, Sophie; Blond, Olivier; Khurana, Archana; Baseggio, Lucile; Heavican, Tayla; Ffrench, Martine; Crispatzu, Giuliano; Mondière, Paul; Schrader, Alexandra; Taillardet, Morgan; Thaunat, Olivier; Martin, Nadine; Dalle, Stéphane; Le Garff-Tavernier, Magali; Salles, Gilles; Lachuer, Joel; Hermine, Olivier; Asnafi, Vahid; Roussel, Mikael; Lamy, Thierry; Herling, Marco; Iqbal, Javeed; Buffat, Laurent; Marche, Patrice N; Gaulard, Philippe; Kronenberg, Mitchell; Defrance, Thierry; Genestier, Laurent
Peripheral T cell lymphomas (PTCLs) are a heterogeneous entity of neoplasms with poor prognosis, lack of effective therapies, and a largely unknown pathophysiology. Identifying the mechanism of lymphomagenesis and cell-of-origin from which PTCLs arise is crucial for the development of efficient treatment strategies. In addition to the well-described thymic lymphomas, we found that p53-deficient mice also developed mature PTCLs that did not originate from conventional T cells but from CD1d-restricted NKT cells. PTCLs showed phenotypic features of activated NKT cells, such as PD-1 up-regulation and loss of NK1.1 expression. Injections of heat-killed Streptococcus pneumonia, known to express glycolipid antigens activating NKT cells, increased the incidence of these PTCLs, whereas Escherichia coli injection did not. Gene expression profile analyses indicated a significant down-regulation of genes in the TCR signaling pathway in PTCL, a common feature of chronically activated T cells. Targeting TCR signaling pathway in lymphoma cells, either with cyclosporine A or anti-CD1d blocking antibody, prolonged mice survival. Importantly, we identified human CD1d-restricted lymphoma cells within Vδ1 TCR-expressing PTCL. These results define a new subtype of PTCL and pave the way for the development of blocking anti-CD1d antibody for therapeutic purposes in humans. PMID:27069116
Fresnel Lenses fabricated by femtosecond laser micromachining on Polymer 1D Photonic Crystal
Directory of Open Access Journals (Sweden)
Guduru Surya S.K.
Full Text Available We report the fabrication of micro Fresnel lenses by femtosecond laser surface ablation on polymer 1D photonic crystals. This device is designed to focus the transmitted wavelength of the photonic crystal and filter the wavelengths corresponding to the photonic band gap region. Integration of such devices in a wavelength selective light harvesting and filtering microchip can be achieved.
Glucose sensor using periodic nanostructured hybrid 1D Au/ZnO arrays
Energy Technology Data Exchange (ETDEWEB)
Huh, Pil Ho, E-mail: email@example.com [Samsung Electronics Co., Ltd. Nongseo-Dong, Giheung-Gu, Yongin-City, Gyeonggi-Do 446-711 (Korea, Republic of); Kim, Myunghwan [Samsung Electronics Co., Ltd. Nongseo-Dong, Giheung-Gu, Yongin-City, Gyeonggi-Do 446-711 (Korea, Republic of); Kim, Seong-Cheol, E-mail: firstname.lastname@example.com [School of Textiles, Yeungnam University, Gyeungsan Gyeungbuk 712-749 (Korea, Republic of)
Hybrid 1D nanostructured Au/ZnO arrays were created by heat treatment of a spin-coated zinc acetate-PVA-Au(III) layer on surface relief grating and functioned as an electrochemical and optical D(+)-glucose sensor due to electrochemical oxidation between hybrid nanostructures and D(+)-glucose. The morphology and chemical composition of 1D Au/ZnO hybrid arrays were characterized by means of AFM, SEM, EDAX, and XPS. Electrochemical and optical sensitivities by the addition of D(+)-glucoses on 1D Au/ZnO arrays were investigated using Cyclic voltammetry and UV-vis-NIR spectra in the medical concentration ranges of 0.5, 2.0, and 8.0 mM. - Highlights: Black-Right-Pointing-Pointer Zinc acetate-PVA-Au(III) composites were prepared by simply mixing zinc acetate-PVA and gold(III) chloride trihydrate. Black-Right-Pointing-Pointer Hybrid 1D nanostructured Au/ZnO arrays were easily fabricated using surface relief gratings without additional process steps. Black-Right-Pointing-Pointer Redox and optical sensor to detect D(+)-glucoses.
(3+1)D Anomalous Twisted Gauge Theories with Global Symmetry
Ye, Peng
In (3+1)D twisted gauge theories, global symmetry may be imposed on topological currents $\\star\\frac{1}{2\\pi}db^I$ in a hydrodynamical way ($I=1,2,\\cdots$, $\\{b^I\\}$ is a set of Kalb-Ramond gauge fields). This methodology has been applied before in the Chern-Simons theory of fractional quantum Hall liquids. We find that, in some twisted gauge theories (with discrete Abelian gauge group $G_g$), implementing a global symmetry (denoted by $G_s$) is always inconsistent. There are two consequences. First, the symmetry-enriched topological order (SET) of the ground state is anomalous, which cannot exist in (3+1)D system alone. It can exist as a boundary of 4+1D topological phases. Second, if $G_s$ is fully gauged, the resulting new gauge theory has gauge anomaly. A (4+1)D topological phase is required to cancel this anomaly. We elaborate this phenomenon via a concrete example.
Plasma as a tool for growth of 1D and 2D nanomaterials and their conversions
Cvelbar, Uros
The growth of 1D and 2D nanostructures in low pressure oxygen plasma is presented with the special stress on metal-oxide nanowires and their deterministic growth mechanisms. Since the resulting nanostructures not always have required properties for applications their modifications are required. Therefore their conversions into different oxides or sulphites/nitrides are required with either molecules, atoms, electrons or photons.
Institute of Scientific and Technical Information of China (English)
黎勇; 陈丽
In this paper, we study the asymptotic behavior of global smooth solution to the initial boundary problem for the 1-D energy transport model in semiconductor science. We prove that the smooth solution of the problem converges to a stationary solution exponentially fast as t - ∞ when the initial data is a small perturbation of the stationary solution.
1D Cahn-Hilliard equation: Ostwald ripening and application to modulated phase systems
Villain-Guillot, Simon
Using an approximate analytical solution of the Cahn-Hilliard equation describing the coalescence during a first order phase transition, we compute the characteristic time for one step of period doubling in Langer's self similar scenario for Ostwald ripening. As an application, we compute the thermodynamically stable period of a 1D modulated phase pattern.
The Missing Heritability in T1D and Potential New Targets for Prevention
Directory of Open Access Journals (Sweden)
Brian G. Pierce
Full Text Available Type 1 diabetes (T1D is a T cell-mediated disease. It is strongly associated with susceptibility haplotypes within the major histocompatibility complex, but this association accounts for an estimated 50% of susceptibility. Other studies have identified as many as 50 additional susceptibility loci, but the effect of most is very modest (odds ratio (OR 5 and that deletion of Vβ13+ T cells prevents diabetes. A role for the TCR is also suspected in NOD mice, but TCR regions have not been associated with human T1D. To investigate this disparity, we tested the hypothesis in silico that previous studies of human T1D genetics were underpowered to detect MHC-contingent TCR susceptibility. We show that stratifying by MHC markedly increases statistical power to detect potential TCR susceptibility alleles. We suggest that the TCR regions are viable candidates for T1D susceptibility genes, could account for "missing heritability," and could be targets for prevention.
On the self-assembly of TiOx into 1D NP network nanostructures
International Nuclear Information System (INIS)
Here, we report for the first time a 'ligand free' method of designing 1D TiOx supramolecular network materials, which starts from Ti bare metal powder. Each TiOx oxidation step has been carefully investigated with different analytical techniques, including high resolution transmission electron microscopy/high resolution scanning electron microscopy (HRTEM/HRSEM), x-ray photoelectron spectroscopy (XPS), Raman spectroscopy and superconducting quantum interference device (SQUID) measurements. The self-assembly of TiOx nanoparticles (NPs) into 1D supramolecular nanoparticle networks is induced by the formation of mixed valent TiII,III species. The synthesis starts with etching a bare Ti surface, followed by a continuous oxidation of TiOx clusters and NPs, and it finally ends with the self-assembly into rigid 1D NPs chains. Today, such self-assembled 1D NP TiOx network materials are bridging the gap between the nanoscale and the macroscopic material world and will further provide interesting research opportunities. (fast track communication)
Data of evolutionary structure change: 1BU1D-1QLYA [Confc[Archive
Lifescience Database Archive (English)
Full Text Available 1BU1D-1QLYA 1BU1 1QLY D A -IIVVALYDYEAIHHEDLSFQKGDQMVVLEESG-EWWKA...RSLATRKEGYIPSNYVARV- LKKVVALYDYMPMNANDLQLRKGDEYFILEESNLPWWRARDK-NGQEGYIPSNYVTEAE -...A 277 TRP CA 316 LYS CA 330 ALA CA 359 1QL...Y A 1QLYA LEESNLPWW...21347046 2.311821937561035 1 1QL
Thermodynamics of 1D N-Component Bariev Model Under Open Boundary Conditions
Institute of Scientific and Technical Information of China (English)
WANG Chun; KE San-Min; YUE Rui-Hong
The thermodynamic Bethe ansatz equations and free energy for 1D N-component Bariev model under open boundary conditions are derived based on the string hypothesis for both, a repulsive and an attractive interaction.These equations are discussed in some limiting cases, such as the ground state, weak and strong couplings.
Exponentially long Equilibration times in a 1-D Collisional Model of a classical gas
DEFF Research Database (Denmark)
Hjorth, Poul; Benettin, G.
separation between the time scale for the vibration and the time scale associated with a typical binary collision in the gas. We consider here a simple 1-D model, and show how, when these time scales are well separated, the collisional dynamics is constrained by a many-particle adiabatic invariant...
Experimental Conditions: SE19_S2_M1_D1 [Metabolonote[Archive
Lifescience Database Archive (English)
Full Text Available SE19_S2_M1_D1 SE19 Grobal triacylglycerol analysis in mouse liver and white adipose... tissue (WAT) by high resolution LC/ESI-QTOF MS/MS SE19_S2 Mouse white adipose tissue (WAT) SE19_S2_M1 20 ug
Data of evolutionary structure change: 1D5IH-3FZUH [Confc[Archive
Lifescience Database Archive (English)
Full Text Available ntryIDChain> CKATG--YTFSS >EEEE -- GGG> 3FZU H 3FZUH CAASGFRFTFNN ...>EEEE GGGure> ATOM 1790 CA CYS H 22 34.95...SW >EEEE ---- > ATOM 2413 CA ALA...pdbChain> 1D5IH ARGHSYYFYDGDYW >EE
Solvent-free porous framework resulted from 3D entanglement of 1D zigzag coordination polymer
Kole, Goutam Kumar Umar
A solvent-free porous metal organic framework is constructed by the 3D entanglement of 1D zigzag coordination polymeric chains. The role of solvents and the effect of reaction conditions on such unique entanglement are addressed. © 2010 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.
On time-reversal anomaly of 2+1d topological phases
Tachikawa, Yuji
We describe a method to find the anomaly of the time-reversal symmetry of 2+1d topological quantum field theories, by computing the fractional anomalous momentum on the cross-cap background. This allows us, for example, to identify the parameter $\
Millimeter and Submillimeter Studies of O(^1D) Insertion Reactions to Form Molecules of Astrophysical Interest
Hays, Brian; Wehres, Nadine; Deprince, Bridget Alligood; Roy, Althea A. M.; Laas, Jacob; Widicus Weaver, Susanna L.
While both the number of detected interstellar molecules and their chemical complexity continue to increase, understanding of the processes leading to their formation is lacking. Our research group combines laboratory spectroscopy, observational astronomy, and astrochemical modeling for an interdisciplinary examination of the chemistry of star and planet formation. This talk will focus on our laboratory studies of O(^1D) insertion reactions with organic molecules to produce molecules of astrophysical interest. By employing these reactions in a supersonic expansion, we are able to produce interstellar organic reaction intermediates that are unstable under terrestrial conditions; we then probe the products using millimeter and submillimeter spectroscopy. We benchmarked this setup using the well-studied O(^1D) + methane reaction to form methanol. After optimizing methanol production, we moved on to study the O(^1D) + ethylene reaction to form vinyl alcohol (CH_2CHOH), and the O(^1D) + methyl amine reaction to form aminomethanol (NH_2CH_2OH). Vinyl alcohol measurements have now been extended up to 450 GHz, and the associated spectral analysis is complete. A possible detection of aminomethanol has also been made, and continued spectral studies and analysis are underway. We will present the results from these experiments and discuss future applications of these molecular and spectroscopic techniques.
Glucose sensor using periodic nanostructured hybrid 1D Au/ZnO arrays
International Nuclear Information System (INIS)
Hybrid 1D nanostructured Au/ZnO arrays were created by heat treatment of a spin-coated zinc acetate-PVA-Au(III) layer on surface relief grating and functioned as an electrochemical and optical D(+)-glucose sensor due to electrochemical oxidation between hybrid nanostructures and D(+)-glucose. The morphology and chemical composition of 1D Au/ZnO hybrid arrays were characterized by means of AFM, SEM, EDAX, and XPS. Electrochemical and optical sensitivities by the addition of D(+)-glucoses on 1D Au/ZnO arrays were investigated using Cyclic voltammetry and UV–vis-NIR spectra in the medical concentration ranges of 0.5, 2.0, and 8.0 mM. - Highlights: ► Zinc acetate-PVA-Au(III) composites were prepared by simply mixing zinc acetate-PVA and gold(III) chloride trihydrate. ► Hybrid 1D nanostructured Au/ZnO arrays were easily fabricated using surface relief gratings without additional process steps. ► Redox and optical sensor to detect D(+)-glucoses.
Analytical 1-D dual-porosity equivalent solutions to 3-D discrete single-continuum models. Application to karstic spring hydrograph modelling
Cornaton, F
One dimensional analytical porosity-weighted solutions of the dual-porosity model are derived, providing insights on how to relate exchange and storage coefficients to the volumetric density of the high-permeability medium. It is shown that porosity-weighted storage and exchange coefficients are needed when handling highly heterogeneous systems - such as karstic aquifers - using equivalent dual-porosity models. The sensitivity of these coefficients is illustrated by means of numerical experiments with theoretical karst systems. The presented 1-D dual-porosity analytical model is used to reproduce the hydraulic responses of reference 3-D karst aquifers, modelled by a discrete single-continuum approach. Under various stress conditions, simulation results show the relations between the dual-porosity model coefficients and the structural features of the discrete single-continuum model. The calibration of the equivalent 1-D analytical dual-porosity model on reference hydraulic responses confirms the dependence of ...
Assessment of phenol infiltration resilience in soil media by HYDRUS-1D transport model for a waste discharge site.
Adhikari, K; Pal, S; Chakraborty, B; Mukherjee, S N; Gangopadhyay, A
The movement of contaminants through soil imparts a variety of geo-environmental problem inclusive of lithospheric pollution. Near-surface aquifers are often vulnerable to contamination from surface source if overlying soil possesses poor resilience or contaminant attenuation capacity. The prediction of contaminant transport through soil is urged to protect groundwater from sources of pollutants. Using field simulation through column experiments and mathematical modeling like HYDRUS-1D, assessment of soil resilience and movement of contaminants through the subsurface to reach aquifers can be predicted. An outfall site of effluents of a coke oven plant comprising of alarming concentration of phenol (4-12.2 mg/L) have been considered for studying groundwater condition and quality, in situ soil characterization, and effluent characterization. Hydrogeological feature suggests the presence of near-surface aquifers at the effluent discharge site. Analysis of groundwater of nearby locality reveals the phenol concentration (0.11-0.75 mg/L) exceeded the prescribed limit of WHO specification (0.002 mg/L). The in situ soil, used in column experiment, possess higher saturated hydraulic conductivity (KS = 5.25 × 10(-4) cm/s). The soil containing 47 % silt, 11 % clay, and 1.54% organic carbon content was found to be a poor absorber of phenol (24 mg/kg). The linear phenol adsorption isotherm model showed the best fit (R(2) = 0.977, RMSE = 1.057) to the test results. Column experiments revealed that the phenol removal percent and the length of the mass transfer zone increased with increasing bed heights. The overall phenol adsorption efficiency was found to be 42-49%. Breakthrough curves (BTCs) predicted by HYDRUS-1D model appears to be close fitting with the BTCs derived from the column experiments. The phenol BTC predicted by the HYDRUS-1D model for 1.2 m depth subsurface soil, i.e., up to the depth of groundwater in the study area, showed that the exhaustion
1D Ladder-like Chain and 1D Channeled 3D Supramolecular Architectures Based on Benzophenone-2,4'-dicarboxylic Acid
Institute of Scientific and Technical Information of China (English)
YANG Xiao-Gang; LI Dong-Sheng; FU Feng; WU Ya-Pan; WANG Ji-Jiang; WANG Yao-Yu
The hydrothermal reactions of AgNO3, 2,2'-bipyridyl, and benzophenone-2,4'-dicarboxylic acid gave rise to two benzophenone-2,4'-dicarboxylic acid). The two compounds are extended by hydrogen bonds in two different apbonding between H2L ligands and water molecules, then extended to a 3D supramolecular architecture. Compound 2 possesses 3D supramolecular architecture containing 1D open channels, which are driven due to the strong H-bonding interactions occurring between the HL anions and water molecules; interestingly, [Ag(bpy)2]+ cations vestigated, the emission maxima for 2 exhibits red-shift compared with that of free ligand and 1 due to chelating effect of the 2,2'-bipyridine ligand to the silver ion and the presence of aromatic π-packing.
Generation and characterization of CD1d-specific single-domain antibodies with distinct functional features.
Lameris, Roeland; de Bruin, Renée C G; van Bergen En Henegouwen, Paul M P; Verheul, Henk M; Zweegman, Sonja; de Gruijl, Tanja D; van der Vliet, Hans J
Ligation of the CD1d antigen-presenting molecule by monoclonal antibodies (mAbs) can trigger important biological functions. For therapeutic purposes camelid-derived variable domain of heavy-chain-only antibodies (VHH) have multiple advantages over mAbs because they are small, stable and have low immunogenicity. Here, we generated 21 human CD1d-specific VHH by immunizing Lama glama and subsequent phage display. Two clones induced maturation of dendritic cells, one clone induced early apoptosis in CD1d-expressing B lymphoblasts and multiple myeloma cells, and another clone blocked recognition of glycolipid-loaded CD1d by CD1d-restricted invariant natural killer T (iNKT) cells. In contrast to reported CD1d-specific mAbs, these CD1d-specific VHH have the unique characteristic that they induce specific and well-defined biological effects. This feature, combined with the above-indicated general advantages of VHH, make the CD1d-specific VHH generated here unique and useful tools to exploit both CD1d ligation as well as disruption of CD1d-iNKT interactions in the treatment of cancer or inflammatory disorders. PMID:27312006
Targeting PPM1D by lentivirus-mediated RNA interference inhibits the tumorigenicity of bladder cancer cells
International Nuclear Information System (INIS)
Protein phosphatase magnesium/manganese-dependent 1D (PPM1D) is a p53-induced phosphatase that functions as a negative regulator of stress response pathways and has oncogenic properties. However, the functional role of PPM1D in bladder cancer (BC) remains largely unknown. In the present study, lentivirus vectors carrying small hairpin RNA (shRNA) targeting PPM1D were used to explore the effects of PPM1D knockdown on BC cell proliferation and tumorigenesis. shRNA-mediated knockdown of PPM1D significantly inhibited cell growth and colony forming ability in the BC cell lines 5637 and T24. Flow cytometric analysis showed that PPM1D silencing increased the proportion of cells in the G0/G1 phase. Downregulation of PPM1D also inhibited 5637 cell tumorigenicity in nude mice. The results of the present study suggest that PPM1D plays a potentially important role in BC tumorigenicity, and lentivirus-mediated delivery of shRNA against PPM1D might be a promising therapeutic strategy for the treatment of BC
Targeting PPM1D by lentivirus-mediated RNA interference inhibits the tumorigenicity of bladder cancer cells
Energy Technology Data Exchange (ETDEWEB)
Wang, W. [Institute of Urology, Huashan Hospital, Fudan University, Shanghai (China); Department of the Intensive Care Unit, Huashan Hospital, Fudan University, Shanghai (China); Zhu, H. [Department of the Intensive Care Unit, Huashan Hospital, Fudan University, Shanghai (China); Zhang, H.; Zhang, L. [Department of Urology, Huashan Hospital, Fudan University, Shanghai (China); Ding, Q.; Jiang, H. [Institute of Urology, Huashan Hospital, Fudan University, Shanghai (China); Department of Urology, Huashan Hospital, Fudan University, Shanghai (China)
Protein phosphatase magnesium/manganese-dependent 1D (PPM1D) is a p53-induced phosphatase that functions as a negative regulator of stress response pathways and has oncogenic properties. However, the functional role of PPM1D in bladder cancer (BC) remains largely unknown. In the present study, lentivirus vectors carrying small hairpin RNA (shRNA) targeting PPM1D were used to explore the effects of PPM1D knockdown on BC cell proliferation and tumorigenesis. shRNA-mediated knockdown of PPM1D significantly inhibited cell growth and colony forming ability in the BC cell lines 5637 and T24. Flow cytometric analysis showed that PPM1D silencing increased the proportion of cells in the G0/G1 phase. Downregulation of PPM1D also inhibited 5637 cell tumorigenicity in nude mice. The results of the present study suggest that PPM1D plays a potentially important role in BC tumorigenicity, and lentivirus-mediated delivery of shRNA against PPM1D might be a promising therapeutic strategy for the treatment of BC.
Advanced Nodal P3/SP3 Axial Transport Solvers for the MPACT 2D/1D Scheme
Energy Technology Data Exchange (ETDEWEB)
Stimpson, Shane G [ORNL; Collins, Benjamin S [ORNL
As part of its initiative to provide multiphysics simulations of nuclear reactor cores, the Consortium for Advanced Simulation of Light Water Reactors (CASL) is developing the Virtual Environment for Reactor Applications Core Simulator (VERA-CS). The MPACT code, which is the primary neutron transport solver of VERA-CS, employs the two-dimensional/one-dimensional (2D/1D) method to solve 3-dimensional neutron transport problems and provide sub-pin-level resolution of the power distribution. While 2D method of characteristics is used to solve for the transport effects within each plane, 1D-nodal methods are used axially. There have been extensive studies of the 2D/1D method with a variety nodal methods, and the P3/SP3 solver has proved to be an effective method of providing higher-fidelity solutions while maintaining a low computational burden.The current implementation in MPACT wraps a one-node nodal expansion method (NEM) kernel for each moment, iterating between them and performing multiple sweeps to resolve flux distributions. However, it has been observed that this approach is more sensitive to convergence problems. This paper documents the theory and application two new nodal P3/SP3 approaches to be used within the 2D/1D method in MPACT. These two approaches aim to provide enhanced stability compared with the pre-existing one-node approach. Results from the HY-NEM-SP3 solver show that the accuracy is consistent with the one-node formulations and provides improved convergence for some problems; but the solver has issues with cases in thin planes. Although the 2N-SENM-SP3 solver is still under development, it is intended to resolve the issues with HY-NEM-SP3 but it will incur some additional computational burden by necessitating an additional 1D-CMFD-P3 solver to generate the second moment cell-averaged scalar flux.
1D and 2D urban dam-break flood modelling in Istanbul, Turkey
Ozdemir, Hasan; Neal, Jeffrey; Bates, Paul; Döker, Fatih
Urban flood events are increasing in frequency and severity as a consequence of several factors such as reduced infiltration capacities due to continued watershed development, increased construction in flood prone areas due to population growth, the possible amplification of rainfall intensity due to climate change, sea level rise which threatens coastal development, and poorly engineered flood control infrastructure (Gallegos et al., 2009). These factors will contribute to increased urban flood risk in the future, and as a result improved modelling of urban flooding according to different causative factor has been identified as a research priority (Gallegos et al., 2009; Ozdemir et al. 2013). The flooding disaster caused by dam failures is always a threat against lives and properties especially in urban environments. Therefore, the prediction of dynamics of dam-break flows plays a vital role in the forecast and evaluation of flooding disasters, and is of long-standing interest for researchers. Flooding occurred on the Ayamama River (Istanbul-Turkey) due to high intensity rainfall and dam-breaching of Ata Pond in 9th September 2009. The settlements, industrial areas and transportation system on the floodplain of the Ayamama River were inundated. Therefore, 32 people were dead and millions of Euros economic loses were occurred. The aim of this study is 1 and 2-Dimensional flood modelling of the Ata Pond breaching using HEC-RAS and LISFLOOD-Roe models and comparison of the model results using the real flood extent. The HEC-RAS model solves the full 1-D Saint Venant equations for unsteady open channel flow whereas LISFLOOD-Roe is the 2-D shallow water model which calculates the flow according to the complete Saint Venant formulation (Villanueva and Wright, 2006; Neal et al., 2011). The model consists a shock capturing Godunov-type scheme based on the Roe Riemann solver (Roe, 1981). 3 m high resolution Digital Surface Model (DSM), natural characteristics of the pond
Bifurcations of families of 1D-tori in 4D symplectic maps
Onken, Franziska; Lange, Steffen; Ketzmerick, Roland; Bäcker, Arnd
The regular structures of a generic 4d symplectic map with a mixed phase space are organized by one-parameter families of elliptic 1d-tori. Such families show prominent bends, gaps, and new branches. We explain these features in terms of bifurcations of the families when crossing a resonance. For these bifurcations, no external parameter has to be varied. Instead, the longitudinal frequency, which varies along the family, plays the role of the bifurcation parameter. As an example, we study two coupled standard maps by visualizing the elliptic and hyperbolic 1d-tori in a 3d phase-space slice, local 2d projections, and frequency space. The observed bifurcations are consistent with the analytical predictions previously obtained for quasi-periodically forced oscillators. Moreover, the new families emerging from such a bifurcation form the skeleton of the corresponding resonance channel.
Analytical investigations of the magnetotelluric directionality estimation in 1-D anisotropic layered media
Okazaki, T.; Oshiman, N.; Yoshimura, R.
Inferring geoelectric dimensionality (1D, 2D or 3D) and directionality (strike directions) from the impedance tensor is a basic procedure in magnetotelluric data processing. Given that electrical anisotropy is increasingly recognized in observations, it is valuable to understand the imprint of anisotropy in these analyses. In this paper, we analytically investigate the estimation of strike directions based on rotational invariants in 1D anisotropic layered media. We first show that if anisotropy axes are identical in all anisotropic layers, the estimated strike coincides with that direction. We then derive an analytical formula of the strike angle at long periods for general anisotropic layers with an isotropic basement. This formula shows a clear physical interpretation that the strike angle points where the conductance integrated along depth takes a maximum value.
Bifurcations of families of 1D-tori in 4D symplectic maps.
Onken, Franziska; Lange, Steffen; Ketzmerick, Roland; Bäcker, Arnd
The regular structures of a generic 4d symplectic map with a mixed phase space are organized by one-parameter families of elliptic 1d-tori. Such families show prominent bends, gaps, and new branches. We explain these features in terms of bifurcations of the families when crossing a resonance. For these bifurcations, no external parameter has to be varied. Instead, the longitudinal frequency, which varies along the family, plays the role of the bifurcation parameter. As an example, we study two coupled standard maps by visualizing the elliptic and hyperbolic 1d-tori in a 3d phase-space slice, local 2d projections, and frequency space. The observed bifurcations are consistent with the analytical predictions previously obtained for quasi-periodically forced oscillators. Moreover, the new families emerging from such a bifurcation form the skeleton of the corresponding resonance channel.
1-D seismic velocity model and hypocenter relocation using double difference method around West Papua region
International Nuclear Information System (INIS)
West Papua region has fairly high of seismicity activities due to tectonic setting and many inland faults. In addition, the region has a unique and complex tectonic conditions and this situation lead to high potency of seismic hazard in the region. The precise earthquake hypocenter location is very important, which could provide high quality of earthquake parameter information and the subsurface structure in this region to the society. We conducted 1-D P-wave velocity using earthquake data catalog from BMKG for April, 2009 up to March, 2014 around West Papua region. The obtained 1-D seismic velocity then was used as input for improving hypocenter location using double-difference method. The relocated hypocenter location shows fairly clearly the pattern of intraslab earthquake beneath New Guinea Trench (NGT). The relocated hypocenters related to the inland fault are also observed more focus in location around the fault
Localized self-heating in large arrays of 1D nanostructures
Monereo, O.; Illera, S.; Varea, A.; Schmidt, M.; Sauerwald, T.; Schütze, A.; Cirera, A.; Prades, J. D.
One dimensional (1D) nanostructures offer a promising path towards highly efficient heating and temperature control in integrated microsystems. The so called self-heating effect can be used to modulate the response of solid state gas sensor devices. In this work, efficient self-heating was found to occur at random networks of nanostructured systems with similar power requirements to highly ordered systems (e.g. individual nanowires, where their thermal efficiency was attributed to the small dimensions of the objects). Infrared thermography and Raman spectroscopy were used to map the temperature profiles of films based on random arrangements of carbon nanofibers during self-heating. Both the techniques demonstrate consistently that heating concentrates in small regions, the here-called ``hot-spots''. On correlating dynamic temperature mapping with electrical measurements, we also observed that these minute hot-spots rule the resistance values observed macroscopically. A physical model of a random network of 1D resistors helped us to explain this observation. The model shows that, for a given random arrangement of 1D nanowires, current spreading through the network ends up defining a set of spots that dominate both the electrical resistance and power dissipation. Such highly localized heating explains the high power savings observed in larger nanostructured systems. This understanding opens a path to design highly efficient self-heating systems, based on random or pseudo-random distributions of 1D nanostructures.One dimensional (1D) nanostructures offer a promising path towards highly efficient heating and temperature control in integrated microsystems. The so called self-heating effect can be used to modulate the response of solid state gas sensor devices. In this work, efficient self-heating was found to occur at random networks of nanostructured systems with similar power requirements to highly ordered systems (e.g. individual nanowires, where their thermal
Static sign language recognition using 1D descriptors and neural networks
Solís, José F.; Toxqui, Carina; Padilla, Alfonso; Santiago, César
A frame work for static sign language recognition using descriptors which represents 2D images in 1D data and artificial neural networks is presented in this work. The 1D descriptors were computed by two methods, first one consists in a correlation rotational operator.1 and second is based on contour analysis of hand shape. One of the main problems in sign language recognition is segmentation; most of papers report a special color in gloves or background for hand shape analysis. In order to avoid the use of gloves or special clothing, a thermal imaging camera was used to capture images. Static signs were picked up from 1 to 9 digits of American Sign Language, a multilayer perceptron reached 100% recognition with cross-validation.
Positron-sensitive vacancy-type centres in the nitrides: 1D-ACAR data
Arutyunov, N. Yu.; Emtsev, V. V.; Mikhailin, A. V.; Humphreys, C. J.
The measurements of one-dimensional angular correlation of the annihilation radiation (1D-ACAR) have been carried out for BN, AlN, and GaN as well as for some related materials that have been used as the reference samples for the analysis of results. The electron-positron ion radii reconstructed by 1D-ACAR for the cation and anion sublattices of the nitrides as well as the estimated average electron density around the positron suggest that: (a) the positron annihilates in the vacancy complexes NGaVN in GaN and NAlVN in AlN, and (b) the cation nearest neighbours are, probably, shifted inward to the VN vacancy where the electron density is sufficiently lower in comparison with that estimated for the bulk.
Positron-sensitive vacancy-type centres in the nitrides: 1D-ACAR data
International Nuclear Information System (INIS)
The measurements of one-dimensional angular correlation of the annihilation radiation (1D-ACAR) have been carried out for BN, AlN, and GaN as well as for some related materials that have been used as the reference samples for the analysis of results. The electron-positron ion radii reconstructed by 1D-ACAR for the cation and anion sublattices of the nitrides as well as the estimated average electron density around the positron suggest that: (a) the positron annihilates in the vacancy complexes NGaVN in GaN and NAlVN in AlN, and (b) the cation nearest neighbours are, probably, shifted inward to the VN vacancy where the electron density is sufficiently lower in comparison with that estimated for the bulk
Quantitative Multiscale Analysis using Different Wavelets in 1D Voice Signal and 2D Image
Shakhakarmi, Niraj
Mutiscale analysis represents multiresolution scrutiny of a signal to improve its signal quality. Multiresolution analysis of 1D voice signal and 2D image is conducted using DCT, FFT and different wavelets such as Haar, Deubachies, Morlet, Cauchy, Shannon, Biorthogonal, Symmlet and Coiflet deploying the cascaded filter banks based decomposition and reconstruction. The outstanding quantitative analysis of the specified wavelets is done to investigate the signal quality, mean square error, entropy and peak-to-peak SNR at multiscale stage-4 for both 1D voice signal and 2D image. In addition, the 2D image compression performance is significantly found 93.00% in DB-4, 93.68% in bior-4.4, 93.18% in Sym-4 and 92.20% in Coif-2 during the multiscale analysis.
Structurally unstable regular dynamics in 1D piecewise smooth maps, and circle maps
International Nuclear Information System (INIS)
Highlights: ► A discontinuous 1D map with two discontinuity points is considered. ► Dynamic behaviors are either periodic or quasiperiodic. ► Dynamics are always structurally unstable. ► Any small perturbation in one of the parameters leads to different dynamics. - Abstract: In this work we consider a simple system of piecewise linear discontinuous 1D map with two discontinuity points: X′ = aX if ∣X∣ z, where a and b can take any real value, and may have several applications. We show that its dynamic behaviors are those of a linear rotation: either periodic or quasiperiodic, and always structurally unstable. A generalization to piecewise monotone functions X′ = F(X) if ∣X∣ z is also given, proving the conditions leading to a homeomorphism of the circle.
Rotating condensed-boson gases in a 1D lattice at finite temperature
Energy Technology Data Exchange (ETDEWEB)
Hassan, Ahmed S.; Soliman, Shemi S.M., E-mail: firstname.lastname@example.com
In this paper, we study the thermodynamic properties of a rotating boson gases in a one-dimensional (1D) optical lattice at finite temperature. Our system is formed by loading three-dimensional boson-clouds into 1D optical lattice and subjected to rotate with angular velocity Ω about the z-axis (rotating condensate in a quasi-two-dimensional trap). We employ the semiclassical approximation to calculate the condensate fraction, critical temperature and the heat capacity of the system. The calculated results show that the rotating condensates in a quasi-two-dimensional have interesting properties which are absent in both three or pure two-dimensional systems. Our results can be extended to investigate the current experiments of rotating Bose–Einstein condensation produced or transferred in one-dimensional optical lattices.
Controlling Interface States in 1D Photonic Crystals by tuning Bulk Geometric Phases
Gao, Wensheng; Chen, Baojie; Pun, Edwin Y B; Chan, C T; Tam, Wing Yim
Interface states in photonic crystals usually require defects or surface/interface decorations. We show here that one can control interface states in 1D photonic crystals through the engineering of geometrical phase such that interface states can be guaranteed in even or odd, or in all photonic bandgaps. We verify experimentally the designed interface states in 1D multilayered photonic crystals fabricated by electron beam vapor deposition. We also obtain the geometrical phases by measuring the reflection phases at the bandgaps of the PCs and achieve good agreement with the theory. Our approach could provide a platform for the design of using interface states in photonic crystals for nonlinear optic, sensing, and lasing applications
Effect of the deformation operator in the D1D5 CFT
Carson, Zaq; Mathur, Samir D; Turton, David
The D1D5 CFT gives a holographic dual description of a near-extremal black hole in string theory. The interaction in this theory is given by a marginal deformation operator, which is composed of supercharges acting on a twist operator. The twist operator links together different copies of a free CFT. We study the effect of this deformation operator when it links together CFT copies with winding numbers M and N to produce a copy with winding M+N, populated with excitations of a particular form. We compute the effect of the deformation operator in the full supersymmetric theory, firstly on a Ramond-Ramond ground state and secondly on states with an initial bosonic or fermionic excitation. Our results generalize recent work which studied only the bosonic sector of the CFT. Our findings are a step towards understanding thermalization in the D1D5 CFT, which is related to black hole formation and evaporation in the bulk.
Effect of the twist operator in the D1D5 CFT
Carson, Zaq; Mathur, Samir D; Turton, David
The D1D5 CFT has been very useful in the study of black holes. The interaction in this theory involves a twist operator, which links together different copies of a free CFT. For the bosonic fields, we examine the action of this twist when it links together CFT copies with winding numbers M and N to produce a copy with winding M+N. Starting with the vacuum state generates a squeezed state, which we compute. Starting with an initial excitation on one of the copies gives a linear combination of excitations on the final state, which we also compute. These results generalize earlier computations where these quantities were computed for the special case M=N=1. Our results should help in understanding the thermalization process in the D1D5 CFT, which gives the dual of black hole formation in the bulk.
FPGA Implementation of Efficient VLSI Architecture for Fixed Point 1-D DWT Using Lifting Scheme
Directory of Open Access Journals (Sweden)
Durga Sowjanya
Full Text Available In this paper, a scheme for the design of area efficient and high speed pipeline VLSI architecture for the computation of fixed point 1-d discrete wavelet transform using lifting scheme is proposed. The main focus of the scheme is to reduce the number and period of clock cycles and efficient area with little or no overhead on hardware resources. The fixed point representation requires less hardware resources compared with floating point representation. The pipelining architecture speeds up the clock rate of DWT and reduced bit precision reduces the area required for implementation. The architecture has been coded in verilog HDL on Xilinx platform and the target FPGA device used is Virtex-II Pro family, XC2VP7-7board. The proposed scheme requires the least computing time for fixed point 1-D DWT and achieves theless area for implementation, compared with other architectures. So this architecture is realizable for real time processing of DWT computation applications.
Magnetic Anticrossing of 1D Subbands in Coupled Ballistic Double Quantum Wires
International Nuclear Information System (INIS)
We study the low-temperature in-plane magnetoconductance of vertically coupled double quantum wires. Using a novel flip-chip technique, the wires are defined by two pairs of mutually aligned split gates on opposite sides of a s 1 micron thick AlGaAs/GaAs double quantum well heterostructure. We observe quantized conductance steps due to each quantum well and demonstrate independent control of each ID wire. A broad dip in the magnetoconductance at -6 T is observed when a magnetic field is applied perpendicular to both the current and growth directions. This conductance dip is observed only when 1D subbands are populated in both the top and bottom constrictions. This data is consistent with a counting model whereby the number of subbands crossing the Fermi level changes with field due to the formation of an anticrossing in each pair of 1D subbands
1D to 3D Crossover of a Spin-Imbalanced Fermi Gas
Revelle, Melissa C; Olsen, Ben A; Hulet, Randall G
We have characterized the one-dimensional (1D) to three-dimensional (3D) crossover of a two-component spin-imbalanced Fermi gas of 6-lithium atoms in a 2D optical lattice by varying the lattice tunneling and the interactions. The gas phase separates, and we detect the phase boundaries using in situ imaging of the inhomogeneous density profiles. The locations of the phases are inverted in 1D as compared to 3D, thus providing a clear signature of the crossover. By scaling the tunneling rate with respect to the pair binding energy, we observe a collapse of the data to a universal crossover point at a scaled tunneling value of 0.016(1).
Membranes having aligned 1-D nanoparticles in a matrix layer for improved fluid separation
Revanur, Ravindra; Lulevich, Valentin; Roh, Il Juhn; Klare, Jennifer E.; Kim, Sangil; Noy, Aleksandr; Bakajin, Olgica
Membranes for fluid separation are disclosed. These membranes have a matrix layer sandwiched between an active layer and a porous support layer. The matrix layer includes 1-D nanoparticles that are vertically aligned in a porous polymer matrix, and which substantially extend through the matrix layer. The active layer provides species-specific transport, while the support layer provides mechanical support. A matrix layer of this type has favorable surface morphology for forming the active layer. Furthermore, the pores that form in the matrix layer tend to be smaller and more evenly distributed as a result of the presence of aligned 1-D nanoparticles. Improved performance of separation membranes of this type is attributed to these effects.
Multi-centered D1-D5 solutions at finite B-moduli
International Nuclear Information System (INIS)
We study the fate of two-centered D1-D5 systems on T4 away from the singular supergravity point in the moduli space. We do this by considering a background D1-D5 black hole with a self-dual B-field moduli turned on and treating the second center in the probe limit in this background. We find that in general marginal bound states at zero moduli become metastable at finite B-moduli, demonstrating a breaking of supersymmetry. However, we also find evidence that when the charges of both centers are comparable, the effects of supersymmetry breaking become negligible. We show that this effect is independent of string coupling and thus it should be possible to reproduce this in the CFT at weak coupling. We comment on the implications for the fuzzball proposal
Iterative 2-D/1-D methods for the 3-D neutron diffusion calculation
International Nuclear Information System (INIS)
To remedy the problems arising from assembly homogenization and de-homogenization, several efforts have been made to solve directly the heterogeneous problem with a fine mesh and to reduce the computational burden by coupling 2-D planar with 1-D axial solutions using a Transverse Leakage (TL) coupling. However, the potential for a numerical instability at a small axial mesh size has been observed. Lee et al. showed that one of the two existing methods, method A, is mathematically unstable at a small mesh size while the other, method B, is always stable. They also proposed a new method for a 2-D/1-D coupling, method C, and they showed that it is always stable and it provides the best performance in terms of the convergence rate. In this paper another algorithm, method D, is proposed and its stability is also investigated
1-D seismic velocity model and hypocenter relocation using double difference method around West Papua region
Energy Technology Data Exchange (ETDEWEB)
Sabtaji, Agung, E-mail: email@example.com, E-mail: email@example.com [Study Program of Earth Sciences, Faculty of Earth Sciencies and Technology, Institute of Technology Bandung, Bandung 40132 (Indonesia); Indonesia's Agency for Meteorological, Climatological and Geophysics Region V, Jayapura 1572 (Indonesia); Nugraha, Andri Dian, E-mail: firstname.lastname@example.com [Global Geophysics Research Group, Faculty of Mining and Petroleum Engineering, Institute of Technology Bandung, Bandung 40132 (Indonesia)
West Papua region has fairly high of seismicity activities due to tectonic setting and many inland faults. In addition, the region has a unique and complex tectonic conditions and this situation lead to high potency of seismic hazard in the region. The precise earthquake hypocenter location is very important, which could provide high quality of earthquake parameter information and the subsurface structure in this region to the society. We conducted 1-D P-wave velocity using earthquake data catalog from BMKG for April, 2009 up to March, 2014 around West Papua region. The obtained 1-D seismic velocity then was used as input for improving hypocenter location using double-difference method. The relocated hypocenter location shows fairly clearly the pattern of intraslab earthquake beneath New Guinea Trench (NGT). The relocated hypocenters related to the inland fault are also observed more focus in location around the fault.
Design, implementation and analysis of fully digital 1-D controllable multiscroll chaos
Mansingka, Abhinav S.
This paper introduces the fully digital implementation of a 1-D multiscroll chaos generator based on a staircase nonlinearity in the 3rd-order jerk system using the Euler approximation. For the first time, digital design is exploited to provide real-time controllability of (i) number of scrolls, (ii) position in 1-D space, (iii) Euler step size and (iv) system parameter. The effect of variations in these fields on the maximum Lyapunov exponent (MLE) is analyzed. The system is implemented using Verilog HDL and synthesized on an Xilinx Virtex 4 FPGA, exhibiting area utilization less than 3.5% and high performance with experimentally verified throughput up to 3.33 Gbits/s. This fully digital system enables applications in modulation schemes and chaos-based cryptosystems without analog to digital conversion. © 2011 IEEE.
ZnO 1-D nanostructures: Low temperature synthesis and characterizations
Indian Academy of Sciences (India)
Apurba Dev; S Chaudhuri; B N Dev
ZnO is one of the most important semiconductors having a wide variety of applications in photonic, field emission and sensing devices. In addition, it exhibits a wide variety of morphologies in the nano regime that can be grown by tuning the growth habit of the ZnO crystal. Among various nanostructures, oriented 1-D nanoforms are particularly important for applications such as UV laser, sensors, UV LED, field emission displays, piezoelectric nanogenerator etc. We have developed a soft chemical approach to fabricate well-aligned arrays of various 1-D nanoforms like nanonails, nanowires and nanorods. The microstructural and photoluminescence properties of all the structures were investigated and tuned by varying the synthesis parameters. Field emission study from the aligned nanorod arrays exhibited high current density and a low turn-on field. These arrays also exhibited very strong UV emission and week defect emission. These structures can be utilized to fabricate efficient UV LEDs.
Mentor Graphics在京发布1D-3D CFD解决方案
Institute of Scientific and Technical Information of China (English)
7月10日,Mentor Graphics1D-3D CFD解决方案战略发布会在北京举行。作为领先的电子设计自动化技术和MCAE技术的领导厂商,Mentor Graphics Mechanical Analysis部门总经理Erich Buergel分享了最新的产品解决方案。
1D Cahn-Hilliard dynamics: Ostwald ripening and application to modulated phase systems
International Nuclear Information System (INIS)
We use a family of stationary solution of the Cahn-Hilliard dynamics in order to describe the coalescence during a first order phase transition. With this analytical ansatz, we compute the characteristic time for one step of period doubling in Langer's self similar scenario for Ostwald ripening. As an application, the same ansatz is also used to compute the thermodynamically stable period of a 1D modulated phase pattern, described by a Cahn-Hilliard dynamics with long range interaction terms
Piezo-semiconductive quasi-1D nanodevices with or without anti-symmetry.
Araneo, Rodolfo; Lovat, Giampiero; Burghignoli, Paolo; Falconi, Christian
The piezopotential in floating, homogeneous, quasi-1D piezo-semiconductive nanostructures under axial stress is an anti-symmetric (i.e., odd) function of force. Here, after introducing piezo-nano-devices with floating electrodes for maximum piezo-potential, we show that breaking the anti-symmetric nature of the piezopotential-force relation, for instance by using conical nanowires, can lead to better nanogenerators, piezotronic and piezophototronic devices.
Zero finite-temperature charge stiffness within the half-filled 1D Hubbard model
Energy Technology Data Exchange (ETDEWEB)
Carmelo, J.M.P., E-mail: firstname.lastname@example.com [Center and Department of Physics, University of Minho, Campus Gualtar, P-4710-057 Braga (Portugal); Beijing Computational Science Research Center, Beijing 100084 (China); Institut für Theoretische Physik III, Universität Stuttgart, D-70550 Stuttgart (Germany); Gu, Shi-Jian [Beijing Computational Science Research Center, Beijing 100084 (China); Department of Physics and ITP, Chinese University of Hong Kong, Hong Kong (China); Sacramento, P.D. [CFIF, Instituto Superior Técnico, Universidade Técnica de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa (Portugal); Beijing Computational Science Research Center, Beijing 100084 (China)
Even though the one-dimensional (1D) Hubbard model is solvable by the Bethe ansatz, at half-filling its finite-temperature T>0 transport properties remain poorly understood. In this paper we combine that solution with symmetry to show that within that prominent T=0 1D insulator the charge stiffness D(T) vanishes for T>0 and finite values of the on-site repulsion U in the thermodynamic limit. This result is exact and clarifies a long-standing open problem. It rules out that at half-filling the model is an ideal conductor in the thermodynamic limit. Whether at finite T and U>0 it is an ideal insulator or a normal resistor remains an open question. That at half-filling the charge stiffness is finite at U=0 and vanishes for U>0 is found to result from a general transition from a conductor to an insulator or resistor occurring at U=U{sub c}=0 for all finite temperatures T>0. (At T=0 such a transition is the quantum metal to Mott–Hubbard-insulator transition.) The interplay of the η-spin SU(2) symmetry with the hidden U(1) symmetry beyond SO(4) is found to play a central role in the unusual finite-temperature charge transport properties of the 1D half-filled Hubbard model. -- Highlights: •The charge stiffness of the half-filled 1D Hubbard model is evaluated. •Its value is controlled by the model symmetry operator algebras. •We find that there is no charge ballistic transport at finite temperatures T>0. •The hidden U(1) symmetry controls the U=0 phase transition for T>0.
Development of a hybrid deterministic/stochastic method for 1D nuclear reactor kinetics
Terlizzi, Stefano; Rahnema, Farzad; Zhang, Dingkang; Dulla, Sandra; Ravetto, Piero
A new method has been implemented for solving the time-dependent neutron transport equation efficiently and accurately. This is accomplished by coupling the hybrid stochastic-deterministic steady-state coarse-mesh radiation transport (COMET) method [1,2] with the new predictor-corrector quasi-static method (PCQM) developed at Politecnico di Torino [3]. In this paper, the coupled method is implemented and tested in 1D slab geometry.
Uranium(VI) coordination polymers with pyromellitate ligand: Unique 1D channel structures and diverse fluorescence
Energy Technology Data Exchange (ETDEWEB)
Zhang, Yingjie, E-mail: email@example.com [Australian Nuclear Science and Technology Organization, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia); Bhadbhade, Mohan [Mark Wainwright Analytical Centre, University of New South Wales, Kensington, NSW 2052 (Australia); Karatchevtseva, Inna [Australian Nuclear Science and Technology Organization, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia); Price, Jason R. [Australian Synchrotron, 800 Blackburn Road, Clayton, VIC 3168 (Australia); Liu, Hao [Centre for Clean Energy Technology, School of Chemistry and Forensic Science, University of Technology Sydney, PO Box 123, Broadway, Sydney, NSW 2007 (Australia); Zhang, Zhaoming; Kong, Linggen [Australian Nuclear Science and Technology Organization, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia); Čejka, Jiří [Department of Mineralogy, National Museum, Václavské náměstí, 68, Prague 1, 115 79-CZ (Czech Republic); Lu, Kim; Lumpkin, Gregory R. [Australian Nuclear Science and Technology Organization, Locked Bag 2001, Kirrawee DC, NSW 2232 (Australia)
Three new coordination polymers of uranium(VI) with pyromellitic acid (H{sub 4}btca) have been synthesized and structurally characterized. (ED)[(UO{sub 2})(btca)]·(DMSO)·3H{sub 2}O (1) (ED=ethylenediammonium; DMSO=dimethylsulfoxide) has a lamellar structure with intercalation of ED and DMSO. (NH{sub 4}){sub 2}[(UO{sub 2}){sub 6}O{sub 2}(OH){sub 6}(btca)]·~6H{sub 2}O (2) has a 3D framework built from 7-fold coordinated uranyl trinuclear units and btca ligands with 1D diamond-shaped channels (~8.5 Å×~8.6 Å). [(UO{sub 2}){sub 2}(H{sub 2}O)(btca)]·4H{sub 2}O (3) has a 3D network constructed by two types of 7-fold coordinated uranium polyhedron. The unique μ{sub 5}-coordination mode of btca in 3 enables the formation of 1D olive-shaped large channels (~4.5 Å×~19 Å). Vibrational modes, thermal stabilities and fluorescence properties have been investigated. - Graphical abstract: Table of content: three new uranium(VI) coordination polymers with pyromellitic acid (H{sub 4}btca) have been synthesized via room temperature and hydrothermal synthesis methods, and structurally characterized. Two to three dimensional (3D) frameworks are revealed. All 3D frameworks have unique 1D large channels. Their vibrational modes, thermal stabilities and photoluminescence properties have been investigated. - Highlights: • Three new coordination polymers of U(VI) with pyromellitic acid (H{sub 4}btca). • Structures from a 2D layer to 3D frameworks with unique 1D channels. • Unusual µ{sub 5}-(η{sub 1}:η{sub 2}:η{sub 1}:η{sub 2:}η{sub 1}) coordination mode of btca ligand. • Vibrational modes, thermal stabilities and luminescent properties reported.
Generation of nonclassical microwave states using an artificial atom in 1D open space
Hoi I.-C.; Palomaki T.; Lindkvist J.; Johansson G.; Delsing P.; Wilson C.M.
We have embedded an artificial atom, a superconducting transmon qubit, in a 1D open space and investigated the scattering properties of an incident microwave coherent state. By studying the statistics of the reflected and transmitted fields, we demonstrate that the scattered states can be nonclassical. In particular, by measuring the second-order correlation function, $g^{(2)}$, we show photon antibunching in the reflected field and superbunching in the transmitted field. We also compare the ...
A Fulling-Kuchment theorem for the 1D harmonic oscillator
Guillemin, Victor
We prove that there exists a pair of "non-isospectral" 1D semiclassical Schr\\"odinger operators whose spectra agree modulo h^\\infty. In particular, all their semiclassical trace invariants are the same. Our proof is based on an idea of Fulling-Kuchment and Hadamard's variational formula applied to suitable perturbations of the harmonic oscillator. Keywords: Inverse spectral problems, semiclassical Schr\\"odinger operators, trace invariants, Hadamard's variational formula, harmonic oscillator, Penrose mushroom, Sturm-Liouville theory.
Application of the ''generalized Riemann problem'' method to 1-D compressible flows with material interfaces
International Nuclear Information System (INIS)
The ''Generalized Riemann Problem'' (GRP) method is applied to 1-D compressible flows with material interfaces and variable cross section. The resulting scheme is second-order and used a ''mixed-type'' grid, where cell boundaries can be either Lagrangian or Eulerian. In fact, using the analytic resolution of discontinuities at cell boundaries, provided by the GRP solution, one can extend the scheme presented here to include any adaptive mesh
Exact electron states in 1D (quasi-) periodic arrays of delta-potentials
Kramer, Peter; Kramer, Tobias
Exact one-electron eigenstates in finite parts of 1D periodic and Fibonacci chains of attractive and repulsive delta potentials are computed and analyzed. Bloch and bound state boundary conditions are related in terms of transfer matrices. Scenarios of positive and negative energy are distinguished. The dependence on the potential strength parameter is analyzed. The scattering matrix is computed. Implications for the interpretation of band germs in quasiperiodic chains are discussed.
Transfer Matrix Approach to 1d Random Band Matrices: Density of States
Shcherbina, Mariya; Shcherbina, Tatyana
We study the special case of n× n 1D Gaussian Hermitian random band matrices, when the covariance of the elements is determined by the matrix J=(-W^2triangle +1)^{-1}. Assuming that n≥ CW log W≫ 1, we prove that the averaged density of states coincides with the Wigner semicircle law up to the correction of order W^{-1}.
Implementation of 1D Ground Response Analysis in Probabilistic Assessments of Ground Shaking Potential
Stewart, Jonathan P.; Goulet, Christine A.; Bazzurro, Paolo; Claassen, Rebecca
Results of 1D ground response analyses are typically not incorporated into probabilistic seismic hazard analyses (PSHA) in a statistically robust way. Often ground response is incorporated into PSHA using deterministic amplification factors. This simplistic method generates results that are intrinsically arbitrary and often unconservative. The main problem in probabilistically linking PSHA and ground response lies in quantifying the dispersion that is appropriate for use with ground respon...
A positron 1D-ACAR spectrometer for the study of 60Co containing materials
International Nuclear Information System (INIS)
In order to study some micro-structural changes in irradiated nuclear reactor-pressure vessel steels using a positron annihilation technique, a new three-detector set-up, suitable for a positron 1-dimensional angular correlation of annihilation radiation (1D-ACAR) study of 60Co-containing materials, was developed. The design of the equipment as well as results from test measurements are described. (orig.)
Periodic Solutions of the 1D Vlasov-Maxwell System with Boundary Conditions
Bostan, Mihai
We study the 1D Vlasov-Maxwell system with time periodic boundary conditions in its classical and relativistic form. For small data we prove existence of weak periodic solutions. It is necessary to impose non vanishing conditions for the incoming velocities in order to control the life-time of particles in the domain. In order to preserve the periodicity, another condition of vanishing the time average of the incoming current is imposed.
Scattering coefficients and gray-body factor for 1D BEC acoustic black holes: exact results
Fabbri, Alessandro; Anderson, Paul R
A complete set of exact analytic solutions to the mode equation are found in the region exterior to the acoustic horizon for a class of 1D Bose-Einstein condensate (BEC) acoustic black holes. From these, analytic expressions for the scattering coefficients and gray-body factor are obtained. The results are used to verify previous predictions regarding the behaviors of the scattering coefficients and gray-body factor in the low frequency limit.
Ultracold Bose Gases in 1D Disorder: From Lifshits Glass to Bose-Einstein Condensate
Lugan, Pierre; Clément, David; Bouyer, Philippe; Aspect, Alain; Lewenstein, Maciej; Sanchez-Palencia, Laurent
We study an ultracold Bose gas in the presence of 1D disorder for repulsive inter-atomic interactions varying from zero to the Thomas-Fermi regime. We show that for weak interactions the Bose gas populates a finite number of localized single-particle Lifshits states, while for strong interactions a delocalized disordered Bose-Einstein condensate is formed. We discuss the schematic quantum-state diagram and derive the equations of state for various regimes.
High-Resolution Radiation Hybrid Map of Wheat Chromosome 1D
Kalavacharla, Venu; Hossain, Khwaja; Gu, Yong; Riera-Lizarazu, Oscar; Vales, M. Isabel; Bhamidimarri, Suresh; Gonzalez-Hernandez, Jose L.; Maan, Shivcharan S; Kianian, Shahryar F
Physical mapping methods that do not rely on meiotic recombination are necessary for complex polyploid genomes such as wheat (Triticum aestivum L.). This need is due to the uneven distribution of recombination and significant variation in genetic to physical distance ratios. One method that has proven valuable in a number of nonplant and plant systems is radiation hybrid (RH) mapping. This work presents, for the first time, a high-resolution radiation hybrid map of wheat chromosome 1D (D geno...
Two Qubits Entanglement Dynamics in 1D Heisenberg Chain with Intrinsic Decoherence
Institute of Scientific and Technical Information of China (English)
SHAO Bin; ZHANG Li-li; ZOU Jian
To reveal how the decoherence modifies the time evolution of the entanglement of quantum system,the intrinsic decoherence approach and the entanglement of formation are used, and the time evolution of entanglement for two-qubit 1D quantum Heisenberg model in an external uniform magnetic field is derived. It is shown that the external magnetic field can strengthen the effects of the intrinsic decoherence on the entanglement of the system.
Energy Technology Data Exchange (ETDEWEB)
B. D. Ganapol; D. W. Nigg
In the mid 80's, a four-group/two-region, entirely analytical 1D nodal benchmark appeared. It was readily acknowledged that this special case was as far as one could go in terms of group number and still achieve an analytical solution. In this work, we show that by decomposing the solution to the multigroup diffusion equation into homogeneous and particular solutions, extension to any number of groups is a relatively straightforward exercise using the mathematics of linear algebra.
Finite difference approximation of control via the potential in a 1-D Schrodinger equation
Directory of Open Access Journals (Sweden)
K. Kime
Full Text Available We consider the problem of steering given initial data to given terminal data via a time-dependent potential, the control, in a 1-D Schrodinger equation. We determine a condition for existence of a transferring potential within our approximation. Using Maple, we give equations for the control and also examples in which the potential is restricted to be centralized and to be a step potential.
Insulin stimulation regulates AS160 and TBC1D1 phosphorylation sites in human skeletal muscle
DEFF Research Database (Denmark)
Middelbeek, R J W; Chambers, M A; Tantiwong, P;
Individuals with obesity and type 2 diabetes (T2D) are typically insulin resistant, exhibiting impaired skeletal muscle glucose uptake. Animal and cell culture experiments have shown that site-specific phosphorylation of the Rab-GTPase-activating proteins AS160 and TBC1D1 is critical for GLUT4 tr...... translocation facilitating glucose uptake, but their regulation in human skeletal muscle is not well understood....
Fragmentation and the Bose-glass phase transition of the disordered 1D Bose gas
Fontanesi, Luca; Wouters, Michiel; Savona, Vincenzo
We investigate the superfluid-insulator quantum phase transition in a disordered 1D Bose gas in the mean field limit, by studying the probability distribution of the density. The superfluid phase is characterized by a vanishing probability to have zero density, whereas a nonzero probability marks the insulator phase. This relation is derived analytically, and confirmed by a numerical study. This fragmentation criterion is particularly suited for detecting the phase transition in experiments. ...
Universality for SU(2) Yang-Mills theory in (2+1)D
Hamer, C J; Weihong, Z; Schütte, D R; Weihong, Zheng
The Green's Function Monte Carlo method of Chin et al is applied to SU(2) Yang-Mills theory in (2+1)D. Accurate measurements are obtained for the ground-state energy and mean plaquette value, and for various Wilson loops. The results are compared with series expansions and coupled cluster estimates, and with the Euclidean Monte Carlo results of Teper. A striking demonstration of universality between the Hamiltonian and Euclidean formulations is obtained.
Controlled Growth and Field-emission Application of 1D ZnS Nanostructures
Institute of Scientific and Technical Information of China (English)
X.S.Fang; Y.Bando; D.Golberg
1 Results One-dimensional (1D) nanostructures have recently stimulated great interest due to their potential value for understanding fundamental physical concepts and for applications in constructing nanoscale electric and optoelectronic devices since the discovery of carbon nanotubes[1]. ZnS is one of the first semiconductors discovered and probably one of the most important materials in the electronics industry with a wide range of applications[2]. Controllable growth of nanostructures is a crucial is...
Surface defect inspection of TFT-LCD panels based on 1D Fourier method
Zhang, Teng-da; Lu, Rong-sheng
Flat panel displays have been used in a wide range of electronic devices. The defects on their surfaces are an important factor affecting the product quality. Automated optical inspection (AOI) method is an important and effective means to perform the surface defection inspection. In this paper, a kind of defect extraction algorithm based on one dimensional (1D) Fourier theory for the surface defect extraction with periodic texture background is introduced. In the algorithm, the scanned surface images are firstly transformed from time domain to frequency domain by 1D Fourier transform. The periodic texture background on the surface is then removed by using filtering methods in the frequency domain. Then, a dual-threshold statistical control method is applied to separate the defects from the surface background. Traditional 1D Fourier transform scheme for detecting ordinary defects is very effective; however, the method is not where the defect direction is close to horizontal in periodic texture background. In order to tackle the problem, a mean threshold method based on faultless image is put forward. It firstly calculates the upper and lower control limits of the every reconstructed line scanned image with faultless and then computes the averages of the upper and lower limits. The averages then act as the constant double thresholds to extract the defects. The experimental results of different defects show that the method developed in the paper is very effective for TFT-LCD panel surface defect inspection even in the circumstance that the defect directions are close to horizontal.
Numerical Modeling of Imploding Plasma liners Using the 1D Radiation-Hydrodynamics Code HELIOS
Davis, J. S.; Hanna, D. S.; Awe, T. J.; Hsu, S. C.; Stanic, M.; Cassibry, J. T.; Macfarlane, J. J.
The Plasma Liner Experiment (PLX) is attempting to form imploding plasma liners to reach 0.1 Mbar upon stagnation, via 30--60 spherically convergent plasma jets. PLX is partly motivated by the desire to develop a standoff driver for magneto-inertial fusion. The liner density, atomic makeup, and implosion velocity will help determine the maximum pressure that can be achieved. This work focuses on exploring the effects of atomic physics and radiation on the 1D liner implosion and stagnation dynamics. For this reason, we are using Prism Computational Science's 1D Lagrangian rad-hydro code HELIOS, which has both equation of state (EOS) table-lookup and detailed configuration accounting (DCA) atomic physics modeling. By comparing a series of PLX-relevant cases proceeding from ideal gas, to EOS tables, to DCA treatments, we aim to identify how and when atomic physics effects are important for determining the peak achievable stagnation pressures. In addition, we present verification test results as well as brief comparisons to results obtained with RAVEN (1D radiation-MHD) and SPHC (smoothed particle hydrodynamics).
A two-layer $\\alpha\\omega$ dynamo model, and its implications for 1-D dynamos
Roald, C B
I will discuss an attempt at representing an interface dynamo in a simplified, essentially 1D framework. The operation of the dynamo is broken up into two 1D layers, one containing the $\\alpha$ effect and the other containing the $\\omega$ effect, and these two layers are allowed to communicate with each other by the simplest possible representation of diffusion, an analogue of Newton's law of cooling. Dynamical back-reaction of the magnetic field on them with diagrams I computed for a comparable purely 1D model. The bifurcation structure shows remarkable similarity, but a couple of subtle changes imply dramatically different physical behaviour for the model. In particular, the solar-like dynamo mode found in the 1-layer model is not stable in the 2-layer version; instead there is an (apparent) homoclinic bifurcation and a sequence of periodic, quasiperiodic, and chaotic modes. I argue that the fragility of these models makes them effectively useless as predictors or interpreters of more complex dynamos.
Quantitative 3D electromagnetic field determination of 1D nanostructures from single projection.
Phatak, C; de Knoop, L; Houdellier, F; Gatel, C; Hÿtch, M J; Masseboeuf, A
One-dimensional (1D) nanostructures have been regarded as the most promising building blocks for nanoelectronics and nanocomposite material systems as well as for alternative energy applications. Although they result in confinement of a material, their properties and interactions with other nanostructures are still very much three-dimensional (3D) in nature. In this work, we present a novel method for quantitative determination of the 3D electromagnetic fields in and around 1D nanostructures using a single electron wave phase image, thereby eliminating the cumbersome acquisition of tomographic data. Using symmetry arguments, we have reconstructed the 3D magnetic field of a nickel nanowire as well as the 3D electric field around a carbon nanotube field emitter, from one single projection. The accuracy of quantitative values determined here is shown to be a better fit to the physics at play than the value obtained by conventional analysis. Moreover the 3D reconstructions can then directly be visualized and used in the design of functional 3D architectures built using 1D nanostructures. PMID:26998702
Study of 1D stranged-charm meson family using HQET
Gupta, Pallavi
Recently LHCb predicted spin 1 and spin 3 states D* s1(2860) and D* s3(2860) which are studied through their strong decays, and are assigned to fit the 13D1and 13D3 states in the charm spectroscopy. In this paper,using the heavy quark effective theory, we state that assigning D*s1(2860) as the mixing of 13D1 - 23S1 states, is rather a better justification to its observed experimental values than a pure state. We study its decay modes variation with hadronic coupling constant gxh and the mixing angle . We appoint spin 3 state D* s3(2860) as the missing 1D 3- JP state, and also study its decay channel behavior with coupling constant gyh. To appreciate the above results, we check the variation of decay modes for their spin partners states i.e. 1D2 and 1D'2 with their masses and strong coupling constant i.e. gxh and gyh. Our calculation using HQET approach give mixing angle between the 13D1 - 23S1 state for D* s1(2860) to lie in the range (-1.6 radians < theta < -1.2 radians). Our calculation for coupling c...
Quantitative 3D electromagnetic field determination of 1D nanostructures from single projection
Energy Technology Data Exchange (ETDEWEB)
Phatak, C.; Knoop, L. de; Houdellier, F.; Gatel, C.; Hÿtch, M. J.; Masseboeuf, A.
One-dimensional (1D) nanostructures have been regarded as the most promising building blocks for nanoelectronics and nanocomposite material systems as well as for alternative energy applications. Although they result in confinement of a material, their properties and interactions with other nanostructures are still very much three-dimensional (3D) in nature. In this work, we present a novel method for quantitative determination of the 3D electromagnetic fields in and around 1D nanostructures using a single electron wave phase image, thereby eliminating the cumbersome acquisition of tomographic data. Using symmetry arguments, we have reconstructed the 3D magnetic field of a nickel nanowire as well as the 3D electric field around a carbon nanotube field emitter, from one single projection. The accuracy of quantitative values determined here is shown to be a better fit to the physics at play than the value obtained by conventional analysis. Moreover the 3D reconstructions can then directly be visualized and used in the design of functional 3D architectures built using 1D nanostructures.
Determination of cellular lipids bound to human CD1d molecules.
Directory of Open Access Journals (Sweden)
Daryl Cox
Full Text Available CD1 molecules are glycoproteins that present lipid antigens at the cell surface for immunological recognition by specialized populations of T lymphocytes. Prior experimental data suggest a wide variety of lipid species can bind to CD1 molecules, but little is known about the characteristics of cellular ligands that are selected for presentation. Here we have molecularly characterized lipids bound to the human CD1d isoform. Ligands were eluted from secreted CD1d molecules and separated by normal phase HPLC, then characterized by mass spectroscopy. A total of 177 lipid species were molecularly identified, comprising glycerophospholipids and sphingolipids. The glycerophospholipids included common diacylglycerol species, reduced forms known as plasmalogens, lyso-phospholipids (monoacyl species, and cardiolipins (tetraacyl species. The sphingolipids included sphingomyelins and glycosylated forms, such as the ganglioside GM3. These results demonstrate that human CD1d molecules bind a surprising diversity of lipid structures within the secretory pathway, including compounds that have been reported to play roles in cancer, autoimmune diseases, lipid signaling, and cell death.
Avidity-dependent programming of autoreactive T cells in T1D.
Directory of Open Access Journals (Sweden)
Ivana Durinovic-Belló
Full Text Available Fate determination for autoreactive T cells relies on a series of avidity-dependent interactions during T cell selection, represented by two general types of signals, one based on antigen expression and density during T cell development, and one based on genes that interpret the avidity of TCR interaction to guide developmental outcome. We used proinsulin-specific HLA class II tetramers to purify and determine transcriptional signatures for autoreactive T cells under differential selection in type 1 diabetes (T1D, in which insulin (INS genotypes consist of protective and susceptible alleles that regulate the level of proinsulin expression in the thymus. Upregulation of steroid nuclear receptor family 4A (NR4A and early growth response family genes in proinsulin-specific T cells was observed in individuals with susceptible INS-VNTR genotypes, suggesting a mechanism for avidity-dependent fate determination of the T cell repertoire in T1D. The NR4A genes act as translators of TCR signal strength that guide central and peripheral T cell fate decisions through transcriptional modification. We propose that maintenance of an NR4A-guided program in low avidity autoreactive T cells in T1D reflects their prior developmental experience influenced by proinsulin expression, identifying a pathway permissive for autoimmunity.
Tuning the 1D-self-assembly of dicyano-functionalized helicene building-blocks
International Nuclear Information System (INIS)
Full text: Effective control of chirality in supramolecular systems is an important challenge towards the assembly of well-defined nano-architectures from the bottom-up. The chirality transfer from single molecules onto 3D- and 2D-crystals is well known, however chirality in case of the 1D-objects (wires) is largely unexplored. Here we present a study based on Scanning Tunnelling Microscopy (STM) and X-Ray Photoelectron Spectroscopy (XPS) measurements and Density Functional Theory (DFT) calculations to understand the formation of 1D conglomerates from enantiopure dicyano functionalized heptahelicene molecules of both chiralities at different, well defined single-crystal surfaces. We show that the main bonding motif can be switched by temperature, substrate or adatom stimuli. We discuss the key driving forces for the formation of well-ordered long-range arrays and the chirality transfer on the single molecule scale as well as onto the 1D conglomerate as a whole. In comparison of experiment and theory, we deepen the insight into the chirality transfer in competition between molecule-molecule and surface-molecule interactions. (author)
Can oriented-attachment be an efficient growth mechanism for the synthesis of 1D nanocrystals via atomic layer deposition?
Wen, Kechun; He, Weidong
One-dimensional (1D) nanocrystals, such as nanorods and nanowires, have received extensive attention in the nanomaterials field due to their large surface areas and 1D confined transport properties. Oriented attachment (OA) is now recognized as a major growth mechanism for efficiently synthesizing 1D nanocrystals. Recently, atomic layer deposition (ALD) has been modified to be a powerful vapor-phase technique with which to synthesize 1D OA nanorods/nanowires with high efficiency and quality by increasing the temperature and purging time. In this invited mini-review, we look into the advantages of OA and high-temperature ALD, and investigate the potential of employing the OA growth mechanism for the synthesis of 1D nanocrystals via modified ALD, aiming to provide guidance to researchers in the fields of both OA and ALD for efficient synthesis of 1D nanocrystals.
Altered Expression Profile of Renal α1D-Adrenergic Receptor in Diabetes and Its Modulation by PPAR Agonists
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Xueying Zhao
Full Text Available Alpha1D-adrenergic receptor (α1D-AR plays important roles in regulating physiological and pathological responses mediated by catecholamines, particularly in the cardiovascular and urinary systems. The present study was designed to investigate the expression profile of α1D-AR in the diabetic kidneys and its modulation by activation of peroxisome proliferator-activated receptors (PPARs. 12-week-old Zucker lean (ZL and Zucker diabetic fatty (ZD rats were treated with fenofibrate or rosiglitazone for 8–10 weeks. Gene microarray, real-time PCR, and confocal immunofluorescence microscopy were performed to assess mRNA and protein expression of α1D-AR in rat kidney tissue. Using microarray, we found that α1D-AR gene was dramatically upregulated in 22-week-old ZD rats compared to ZL controls. Quantitative PCR analysis verified a 16-fold increase in α1D-AR mRNA in renal cortex from ZD animals compared to normal controls. Chronic treatment with fenofibrate or rosiglitazone reduced renal cortical α1D-AR gene. Immunofluorescence staining confirmed that α1D-AR protein was induced in the glomeruli and tubules of diabetic rats. Moreover, dual immunostaining for α1D-AR and kidney injury molecule-1 indicated that α1D-AR was expressed in dedifferentiated proximal tubules of diabetic Zucker rats. Taken together, our results show that α1D-AR expression is upregulated in the diabetic kidneys. PPAR activation suppressed renal expression of α1D-AR in diabetic nephropathy.
Hydrothermally processed 1D hydroxyapatite: Mechanism of formation and biocompatibility studies.
Stojanović, Zoran S; Ignjatović, Nenad; Wu, Victoria; Žunič, Vojka; Veselinović, Ljiljana; Škapin, Srečo; Miljković, Miroslav; Uskoković, Vuk; Uskoković, Dragan
Recent developments in bone tissue engineering have led to an increased interest in one-dimensional (1D) hydroxyapatite (HA) nano- and micro-structures such as wires, ribbons and tubes. They have been proposed for use as cell substrates, reinforcing phases in composites and carriers for biologically active substances. Here we demonstrate the synthesis of 1D HA structures using an optimized, urea-assisted, high-yield hydrothermal batch process. The one-pot process, yielding HA structures composed of bundles of ribbons and wires, was typified by the simultaneous occurrence of a multitude of intermediate reactions, failing to meet the uniformity criteria over particle morphology and size. To overcome these issues, the preparation procedure was divided to two stages: dicalcium phosphate platelets synthesized in the first step were used as a precursor for the synthesis of 1D HA in the second stage. Despite the elongated particle morphologies, both the precursor and the final product exhibited excellent biocompatibility and caused no reduction of viability when tested against osteoblastic MC3T3-E1 cells in 2D culture up to the concentration of 2.6mg/cm(2). X-ray powder diffraction combined with a range of electron microscopies and laser diffraction analyses was used to elucidate the formation mechanism and the microstructure of the final particles. The two-step synthesis involved a more direct transformation of DCP to 1D HA with the average diameter of 37nm and the aspect ratio exceeding 100:1. The comparison of crystalline domain sizes along different crystallographic directions showed no signs of significant anisotropy, while indicating that individual nanowires are ordered in bundles in the b crystallographic direction of the P63/m space group of HA. Intermediate processes, e.g., dehydration of dicalcium phosphate, are critical for the formation of 1D HA alongside other key aspects of this phase transformation, it must be investigated in more detail in the continuous
Position error in profiles retrieved from MIPAS observations with a 1-D algorithm
Directory of Open Access Journals (Sweden)
M. Carlotti
Full Text Available The information load (IL analysis, first introduced for the two-dimensional approach (Carlotti and Magnani, 2009, is applied to the inversion of MIPAS observations operated with a 1-dimensional (1-D retrieval algorithm. The IL distribution of MIPAS spectra is shown to be often asymmetrical with respect to the tangent points of the observations and permits to identify the preferential latitude where the profiles retrieved with a 1-D algorithm should be geo-located. Therefore a position error is made when the tangent points of the observations are used to assign the geo-location of the retrieved profile. We assess the amplitude of the position error for some of the MIPAS main targets and we show that the IL analysis can also be used as a tool for the selection of observations that, when analyzed, minimize the position error of the retrieved profile. When the temperature (T profiles are used for the retrieval of volume mixing ratio (VMR of atmospheric constituents, the T position error (of the order of 1.5 degrees of latitude induces a VMR error that is directly connected with the horizontal T gradients. Temperature profiles can be externally-provided or determined in a previous step of the retrieval process. In the first case, the IL analysis shows that a meaningful fraction (often exceeding 50% of the VMR error deriving from the 1-D approximation is to be attributed to the mismatch between the position assigned to the external T profile and the positions where T is required by the analyzed observations. In the second case the retrieved T values suffer by an error of 1.5–2 K due to neglecting the horizontal variability of T; however the error induced on VMRs is of minor entity because of the generally small mismatch between the IL distribution of the observations analyzed to retrieve T and those analyzed to retrieve the VMR target. An estimate of the contribution of the
Hydrothermally processed 1D hydroxyapatite: Mechanism of formation and biocompatibility studies.
Stojanović, Zoran S; Ignjatović, Nenad; Wu, Victoria; Žunič, Vojka; Veselinović, Ljiljana; Škapin, Srečo; Miljković, Miroslav; Uskoković, Vuk; Uskoković, Dragan
Recent developments in bone tissue engineering have led to an increased interest in one-dimensional (1D) hydroxyapatite (HA) nano- and micro-structures such as wires, ribbons and tubes. They have been proposed for use as cell substrates, reinforcing phases in composites and carriers for biologically active substances. Here we demonstrate the synthesis of 1D HA structures using an optimized, urea-assisted, high-yield hydrothermal batch process. The one-pot process, yielding HA structures composed of bundles of ribbons and wires, was typified by the simultaneous occurrence of a multitude of intermediate reactions, failing to meet the uniformity criteria over particle morphology and size. To overcome these issues, the preparation procedure was divided to two stages: dicalcium phosphate platelets synthesized in the first step were used as a precursor for the synthesis of 1D HA in the second stage. Despite the elongated particle morphologies, both the precursor and the final product exhibited excellent biocompatibility and caused no reduction of viability when tested against osteoblastic MC3T3-E1 cells in 2D culture up to the concentration of 2.6mg/cm(2). X-ray powder diffraction combined with a range of electron microscopies and laser diffraction analyses was used to elucidate the formation mechanism and the microstructure of the final particles. The two-step synthesis involved a more direct transformation of DCP to 1D HA with the average diameter of 37nm and the aspect ratio exceeding 100:1. The comparison of crystalline domain sizes along different crystallographic directions showed no signs of significant anisotropy, while indicating that individual nanowires are ordered in bundles in the b crystallographic direction of the P63/m space group of HA. Intermediate processes, e.g., dehydration of dicalcium phosphate, are critical for the formation of 1D HA alongside other key aspects of this phase transformation, it must be investigated in more detail in the continuous
HLA class II susceptibility pattern for type 1 diabetes (T1D) in an Iranian population.
Kiani, J; Hajilooi, M; Furst, D; Rezaei, H; Shahryari-Hesami, S; Kowsarifard, S; Zamani, A; Solgi, G
This study aimed to determine the HLA-DRB1/HLA-DQB1 susceptibility and protection pattern for type 1 diabetes (T1D) in a population from Hamadan, north-west of Iran. A total of 133 patients with T1D were tested for HLA-DRB1 and HLA-DQB1 alleles using PCR-SSP compared to 100 ethnic-matched healthy controls. Alleles and haplotypes frequencies were compared between both groups. The most susceptible alleles for disease were HLA-DRB1*03:01, DRB1*04:02, DQB1*02:01 and DQB1*03:02, and protective alleles were HLA-DRB1*07:01, *11:01, *13:01, *14:01 and DRB1*15 and HLA-DQB1*06:01, *06:02 and *06:03. Haplotype analysis revealed that patients with T1D had higher frequencies of DRB1*03:01-DQB1*02:01 (OR = 4.86, P < 10(-7) ) and DRB1*04:02-DQB1*03:02 (OR = 9.93, P < 10(-7) ) and lower frequencies of DRB1*07:01-DQB1*02:01 (P = 0.0005), DRB1*11:01-DQB1*03:01 (P = 0.001), DRB1*13:01-DQB1*06:03 (P = 0.002) and DRB1*15-DQB1*06:01 (P = 0.001) haplotypes compared to healthy controls. Heterozygote combination of both susceptible haplotypes (DR3/DR4) confers the highest risk for T1D (RR = 18.80, P = 4 × 10(-5) ). Additionally, patients with homozygote diplotype, DR3/DR3 and DR4/DR4, showed a similar risk with less extent to heterozygote combination (P = 0.0004 and P = 0.01, respectively). Our findings not only confirm earlier reports from Iranians but also are in line with Caucasians and partly with Asians and some African patients with T1D. Remarkable differences were the identification of DRB1*04:01-DQB1*03:02, DRB1*07:01-DQB1*03:03 and DRB1*16-DQB1*05:02 as neutral and DRB1*13:01-DQB1*06:03 as the most protective haplotypes in this study.
No Shock Across Part of a Radio Relic?
Ogrean, Georgiana; Van Weeren, Reinout J.; Brüggen, Marcus; Simionescu, Aurora; Jones, Christine; Bonafede, Annalisa; Forman, William R.; Kraft, Ralph P.
Radio relics are Mpc-scale, steep-spectrum synchrotron sources in the periphery of merging galaxy clusters, which are produced by particle acceleration at low-Mach number (Mwaves. As expected, signatures of shocks have been found across the full length of all the relics studied to date. However, archival Chandra and XMM observations have revealed a possible exception in the merging galaxy cluster ZwCl 2341.1+0000. The cluster, at z=0.27, hosts two radio relics and a central, faint, filamentary radio structure. In the archival X-ray data, the density discontinuity near the SE relic appears to span an arc shorter than the arc spanned by the relic. This startling result is in apparent contradiction with our current understanding of the origin of radio relics.We present results from recently-completed deep Chandra and VLA observations of the cluster. These observations reveal several merging subclusters, and allow a detailed study of the connection between the radio relics and the shocks in ZwCl 2341.1+0000. We discuss the complex merger scenario that triggered the shock waves, and the implications that the physical properties of the shocks have on our understanding of particle acceleration in merging clusters.
What causes the large extensions of red-supergiant atmospheres? Comparisons of interferometric observations with 1-D hydrostatic, 3-D convection, and 1-D pulsating model atmospheres
Arroyo-Torres, B; Chiavassa, A; Scholz, M; Freytag, B; Marcaide, J M; Hauschildt, P H; Wood, P R; Abellan, F J
We present the atmospheric structure and the fundamental parameters of three red supergiants, increasing the sample of RSGs observed by near-infrared spectro-interferometry. Additionally, we test possible mechanisms that may explain the large observed atmospheric extensions of RSGs. We carried out spectro-interferometric observations of 3 RSGs in the near-infrared K-band with the VLTI/AMBER instrument at medium spectral resolution. To comprehend the extended atmospheres, we compared our observational results to predictions by available hydrostatic PHOENIX, available 3-D convection, and new 1-D self-excited pulsation models of RSGs. Our near-infrared flux spectra are well reproduced by the PHOENIX model atmospheres. The continuum visibility values are consistent with a limb-darkened disk as predicted by the PHOENIX models, allowing us to determine the angular diameter and the fundamental parameters of our sources. Nonetheless, in the case of V602 Car and HD 95686, the PHOENIX model visibilities do not predict ...
A sixth-order finite volume method for the 1D biharmonic operator: Application to intramedullary nail simulation
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Costa Ricardo
Full Text Available A new very high-order finite volume method to solve problems with harmonic and biharmonic operators for onedimensional geometries is proposed. The main ingredient is polynomial reconstruction based on local interpolations of mean values providing accurate approximations of the solution up to the sixth-order accuracy. First developed with the harmonic operator, an extension for the biharmonic operator is obtained, which allows designing a very high-order finite volume scheme where the solution is obtained by solving a matrix-free problem. An application in elasticity coupling the two operators is presented. We consider a beam subject to a combination of tensile and bending loads, where the main goal is the stress critical point determination for an intramedullary nail.
The similarity of interactions between (3+1)D spatiotemporal optical solitons in both the dispersive medium with cubic-quintic nonlinearity and the saturable medium
Institute of Scientific and Technical Information of China (English)
Peng Jin-Zhang; Yang Hong; Tang Yi
By making use of the split-step Fourier method, this paper numerically simulates dynamical behaviors, including repulsion, fusion, scattering and spiraling of colliding (3+1)D spatiotemporal solitons in both the dispersive medium with cubic-quintic and the saturable medium. Careful comparison of the colliding behaviors in these two media is presented. Although the origin of the nonlinearities is different in these two media, the obtained results show that the dynamical behaviors are very similar. This presents additional evidence to support the supposition of universality of interactions between solitons.
Transition from ultrafast laser photo-electron emission to space-charge-limited current in a 1D gap
International Nuclear Information System (INIS)
A one-dimensional (1D) model has been constructed to study the transition of the time-dependent ultrafast laser photo-electron emission from a flat metallic surface to the space-charge-limited (SCL) current, including the effect of non-equilibrium laser heating on metals at the ultrafast time scale. At high laser field, it is found that the space charge (SC) effect cannot be ignored and the SCL current emission is reached at a lower value predicted by a short-pulse SCL current model that has assumed a time-independent emission process. The threshold of the laser field to reach the SCL regime is determined over a wide range of operating parameters. The calculated results agree well with particle-in-cell simulation results. It is found that the SC effect is more important for materials with lower work function like tungsten (4.4 eV) as compared with gold (5.4 eV). However, for a flat surface, both materials will reach the SC limited regime at sufficient high laser field such as >5 GV m−1 with a laser pulse length of 10 s to 100 fs. (paper)
Photochemistry of O(1D) and O(1S) lines in the coma of 67P/Churyumov-Gerasimenko
Cessateur, Gaël; De Keyser, Johan; Maggiolo, Romain; Gibbons, Andrew; Gronoff, Guillaume; Gunell, Herbert; Dhooghe, Frederik; Loreau, Jérôme; Vaeck, Nathalie; Altwegg, Kathrin; Bieler, Andre; Briois, Christelle; Calmonte, Ursina; Combi, Michael; Fuselier, Stephen; Gombosi, Tamas; Haessig, Myrtha; Le Roy, Lena; Neefs, Eddy; Rubin, Martin
We present here a chemistry-emission coupled model to study the production and loss mechanisms of the O(1D) and O(1S) states, for comet 67P/Churyumov-Gerasimenko. The recent discovery of O2 in significant abundance relative to water (3.80% +/- 0.85%, Bieler et al. 2015) within the coma of 67P has been taken into consideration for the first time in such models. We evaluate the effect of the presence of O2 on the green to red-doublet emission intensity ratio, which is traditionally used to assess the CO2 abundance within cometary atmospheres. Model simulations, solving the continuity equation with transport, show that not taking O2 into account leads to an underestimation of the CO2 abundance within 67P. This strongly suggests that the green to red-doublet emission intensity ratio alone is not a proper tool for determining the CO2 abundance, as previously suggested. O2 might indeed be a rather common and abundant parent species, following the re-analysis of the comet 1P/Halley data (Rubin et al. 2015). Therefore, it is likely that earlier determinations of the CO2 abundance in cometary atmospheres have to be revisited.
Mapping temporal extent of Chiang Mai floods using coupled 1-D and quasi 2-D floodplain inundation models
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Kowit Boonrawd
Full Text Available A coupling of a 1-D flood routing model and quasi 2-D floodplain inundation model is applied for mapping spacetime flood extent. The routing model is formulated based on a non-linear storage-discharge relationship which is converted from an observed and synthetic rating curve. To draw the rating curve, required parameters for each reaches are estimated from hydraulic properties, floodplain geometry and vegetation and building cover of compound channels. The shape of the floodplain is defined by using fitting exercise based on the reverse approach between past and simulated inundation flood extent, to solve the current problem of inadequate topographic input data for floodplain. Mapping of daily flood can be generated relying on flat water levels. The quasi 2-D raster model is tested and applied to generate more realistic water surface and is used to estimate flood extent. The model is applied to the floodplains of Chiang Mai, north of Thailand and used to estimate a time series of hourly flood maps. Extending from daily to hourly flood extent, mapping development provides more details of flood inundation extent and depth.
A Dual EnKF for Estimating Water Level, Bottom Roughness, and Bathymetry in a 1-D Hydrodynamic Model
Hooshyar, Milad; Wang, Dingbao; Hagen, Scott C
Data assimilation has been applied to coastal hydrodynamic models to better estimate system states or parameters by incorporating observed data into the model. Kalman Filter (KF) is one of the most studied data assimilation methods whose application is limited to linear systems. For nonlinear systems such as hydrodynamic models a variation of the KF called Ensemble Kalman Filter (EnKF) is applied to update the system state in the context of Monte Carlo simulation. In this research, a dual EnKF approach is used to simultaneously estimate state (water surface elevation) and parameters (bottom roughness and bathymetry) of the shallow water models. The sensitivity of the filter to 1) the quantity and precision of the observations, and 2) the initial estimation of parameters is investigated in a 1-D shallow water problem located in the Gulf of Mexico. Results show that starting from an initial estimate of bottom roughness and bathymetry within a logical range and utilizing observations available at a limited numbe...
Membranes from nanoporous 1D and 2D materials: A review of opportunities, developments, and challenges
Kim, Wun-gwi
Membranes utilizing nanoporous one-dimensional (1D) and two-dimensional (2D) materials are emerging as attractive candidates for applications in molecular separations and related areas. Such nanotubular and nanolayered materials include carbon nanotubes, metal oxide nanotubes, layered zeolites, porous layered oxides, layered aluminophosphates, and porous graphenes. By virtue of their unique shape, size, and structure, they possess transport properties that are advantageous for membrane and thin film applications. These materials also have very different chemistry from more conventional porous 3D materials, due to the existence of a large, chemically active, external surface area. This feature also necessitates the development of innovative strategies to process these materials into membranes and thin films with high performance. This work provides the first comprehensive review of this emerging area. We first discuss approaches for the synthesis and structural characterization of nanoporous 1D and 2D materials. Thereafter, we elucidate different approaches for fabrication of membranes and thin films from these materials, either as multiphase (composite/hybrid) or single-phase membranes. The influence of surface chemistry and processing techniques on the membrane morphology is highlighted. We then discuss the applications of such membranes in areas relating to molecular transport and separation, e.g. gas and liquid-phase separations, water purification, and ion-conducting membranes. The review concludes with a discussion of the present outlook and some of the key scientific challenges to be addressed on the path to industrially applicable membranes containing nanoporous 1D and 2D materials. © 2013 Elsevier Ltd.
Universal low-energy physics in 1D strongly repulsive multi-component Fermi gases
Jiang, Yuzhu; He, Peng; Guan, Xi-Wen
It has been shown (Yang and You 2011 Chin. Phys. Lett. 28 020503) that at zero temperature the ground state of the one-dimensional (1D) w-component Fermi gas coincides with that of the spinless Bose gas in the limit ω \\to ∞ . This behavior was experimentally evidenced through quasi-1D tightly trapping ultracold 173Yb atoms in a recent paper (Pagano et al 2014 Nat. Phys. 10 198). However, understanding of low-temperature behavior of Fermi gases with a repulsive interaction requires spin-charge separated conformal field theories of an effective Tomonaga-Luttinger liquid and an antiferromagnetic SU(w) Heisenberg spin chain. Here we analytically derive universal thermodynamics of 1D strongly repulsive fermionic gases with SU(w) symmetry via the Yang-Yang thermodynamic Bethe ansatz method. The analytical free energy and magnetic properties of the systems at low temperature in a weak magnetic field are obtained through the Wiener-Hopf method. In particular, the free energy essentially manifests the spin-charge separated conformal field theories for high-symmetry systems with arbitrary repulsive interaction strength. We also find that the sound velocity of the Fermi gases in the large w limit coincides with that for the spinless Bose gas, whereas the spin velocity vanishes quickly as w becomes large. This indicates strong suppression of the Fermi exclusion statistics by the commutativity feature among the w-component fermions with different spin states in the Tomonaga-Luttinger liquid phase. Moreover, the equations of state and critical behavior of physical quantities at finite temperature are analytically derived in terms of the polylogarithm functions in the quantum critical region.
O(1D) Reaction with Methane Studied by State Resolved Scattering Distribution Measurements of Methyl Radicals
Suzuki, Toshinori
The scattering distributions of state-selected methyl radicals are measured for the O(^1D_2) reaction with methane using a crossed molecular beam ion imaging method at collision energies of 0.9 - 6.8 kcal/mol. The results are compared with the reaction with deuterated methane to examine the isotope effects. The scattering distributions exhibit contributions from both the insertion and abstraction pathways respectively on the ground and excited-state potential energy surfaces. Insertion is the main pathway, and it provides a strongly forward-enhanced angular distribution of methyl radicals. Abstraction is a minor pathway, causing backward scattering of methyl radicals with a discrete speed distribution. From the collision energy dependence of the abstraction/insertion ratio, the barrier height for the abstraction pathway is estimated for O(^1D_2) with CH_4 and CD_4, respectively. The insertion pathway of the O(^1D_2) reaction with CH_4 has a narrower angular width in the forward scattering and a larger insertion/abstraction ratio than the reaction with CD_4, which indicate that the insertion reaction with CH_4 has a larger cross section and a shorter reaction time than the reaction with CD_4. Additionally, while the insertion reaction with CD_4 exhibits strong angular dependence of the CD_3 speed distribution, CH_3 exhibits considerably smaller dependence. The result suggests that, although intramolecular vibrational redistribution (IVR) within the lifetime of the methanol intermediate is restrictive in both isotopomers, relatively more extensive IVR occurs in CD_3OD than CH_3OH, presumably due to the higher vibrational state density.
Institute of Scientific and Technical Information of China (English)
10月20日佳能(中国)有限公司发布面向职业新闻和体育摄影师的专业数码单反相机EOS-1D Mark IV和支持有线/无线网络及USB控制功能EOS 5D Mark II无线文件传输器WFT-E4 II C为专业影像市场注入了全新的技术动力。
Investigation of 1-D crustal velocity structure beneath Izmir Gulf and surroundings by using local earthquakes
Polat, Orhan; Özer, Ćaglar
In this study; we examined one dimensional crustal velocity structure of Izmir gulf and surroundings. We used nearly one thousand high quality (A and B class) earthquake data which recorded by Disaster and Emergency Management Presidency (AFAD) [1], Bogazici University (BU-KOERI) [2] and National Observatory of Athens (NOA) [3,4]. We tried several synthetic tests to understand power of new velocity structure, and examined phase residuals, RMS values and shifting tests. After evaluating these tests; we decided one dimensional velocity structure and minimum 1-D P wave velocities, hypocentral parameter and earthquake locations from VELEST algorithm. Distribution of earthquakes was visibly improved by using new minimum velocity structure.
Silva. EDF two-phase 1D annular model of a CFB boiler furnace
Energy Technology Data Exchange (ETDEWEB)
Montat, D.; Fauquet, Ph. [Electricite de France (EDF), 78 - Chatou (France). Researckh and Development Div.; Lafanechere, L.; Bursi, J.M. [Electricite de France (EDF) (France). Construction Div.
SILVA computer code is used for the modelling of the thermal-hydraulics and of the combustion of a coal-fired CFBC solid loop. In a first step, only the furnace is considered. The model is based on a 1D annular two phases description of the hydrodynamics. The model is based on particle mass balances and pressure drop calculations. A basic combustion model is incorporated into this model. The coal combustion is divided in two phases, the combustion of volatile matter and the heterogeneous combustion. The model has been developed within LEGO software and can be included into the global model of the solid loop developed by EDF. (author) 26 refs.
Towards 1D nanolines on a monolayered supramolecular network adsorbed on a silicon surface
Makoudi, Younes; Beyer, Matthieu; Lamare, Simon; Jeannoutot, Judicael; Palmino, Frank; Chérioux, Frédéric
The growth of 3D extended periodic networks made up of π-conjugated molecules on semi-conductor surfaces is of interest for the integration of nano-components in the future generations of smart devices. In the work presented in this article, we successfully achieved the formation of bilayered networks on a silicon surface including 1D-isolated nanolines in the second layer. Firstly, we observed the formation of a 2D large-scale supramolecular network in the plane of a silicon surface through the deposition of tailored molecules. Then using the same molecules, a second-layer, based on 1D nanolines, grew above the first layer, thanks to a template effect. Mono- or bi-layered networks were found to be stable from 100 K up to room temperature. These networks were investigated by scanning tunnel microscopy imaging under an ultra-high vacuum (UHV-STM).The growth of 3D extended periodic networks made up of π-conjugated molecules on semi-conductor surfaces is of interest for the integration of nano-components in the future generations of smart devices. In the work presented in this article, we successfully achieved the formation of bilayered networks on a silicon surface including 1D-isolated nanolines in the second layer. Firstly, we observed the formation of a 2D large-scale supramolecular network in the plane of a silicon surface through the deposition of tailored molecules. Then using the same molecules, a second-layer, based on 1D nanolines, grew above the first layer, thanks to a template effect. Mono- or bi-layered networks were found to be stable from 100 K up to room temperature. These networks were investigated by scanning tunnel microscopy imaging under an ultra-high vacuum (UHV-STM). Electronic supplementary information (ESI) available: Additional STM images showing submolecular details of the adsorption of molecules on the surface. See DOI: 10.1039/c6nr01826b
B Cells Promote Th1- Skewed NKT Cell Response by CD1d-TCR Interaction
Shin, Jung Hoon; Park, Se-Ho
CD1d expressing dendritic cells (DCs) are good glyco-lipid antigen presenting cells for NKT cells. However, resting B cells are very weak stimulators for NKT cells. Although α-galactosylceramide (α-GalCer) loaded B cells can activate NKT cells, it is not well defined whether B cells interfere NKT cell stimulating activity of DCs. Unexpectedly, we found in this study that B cells can promote Th1-skewed NKT cell response, which means a increased level of IFN-γ by NKT cells, concomitant with a d...
Numerical modeling of 1-D transient poroelastic waves in the low-frequency range
Chiavassa, Guillaume; Piraux, Joël
Propagation of transient mechanical waves in porous media is numerically investigated in 1D. The framework is the linear Biot's model with frequency-independant coefficients. The coexistence of a propagating fast wave and a diffusive slow wave makes numerical modeling tricky. A method combining three numerical tools is proposed: a fourth-order ADER scheme with time-splitting to deal with the time-marching, a space-time mesh refinement to account for the small-scale evolution of the slow wave, and an interface method to incorporate the jump conditions at interfaces. Comparisons with analytical solutions confirm the validity of this approach.
D1/D5 system and Wilson Loops in (Non-)commutative Gauge Theories
Takahashi, Hidenori; Nakajima, Tadahito; Suzuki, Kenji
We study the behavior of the Wilson loop in the (5+1)-dimensional supersymmetric Yang-Mills theory with the presence of the solitonic object. Using the dual string description of the Yang-Mills theory that is given by the D1/D5 system, we estimate the Wilson loops both in the temporal and spatial cases. For the case of the temporal loop, we obtain the velocity dependent potential. For the spatial loop, we find that the area law is emerged due to the effect of the D1-branes. Further, we consid...
Design for manufacturability from 1D to 4D for 90-22 nm technology nodes
Balasinski, Artur
This book explains integrated circuit design for manufacturability (DfM) at the product level (packaging, applications) and applies engineering DfM principles to the latest standards of product development at 22 nm technology nodes. It is a valuable guide for layout designers, packaging engineers and quality engineers, covering DfM development from 1D to 4D, involving IC design flow setup, best practices, links to manufacturing and product definition, for process technologies down to 22 nm node, and product families including memories, logic, system-on-chip and system-in-package.
GE SBWR stability analysis using TRAC-BF1 1-D kinetics model
International Nuclear Information System (INIS)
GE's simplified boiling water reactor, with its unique feature of using natural circulation to remove the heat from the reactor core, is a complicated dynamic system. Previous work by authors using the TRAC-BF1 code and a point kinetics model predicted that an SBWR may experience large amplitude power oscillation under certain low pressure and high power operating conditions. To further confirm the existence of this power oscillation and explore the dynamic spatial reactor power distribution, the TRAC-BF1 1-D kinetics model was used. The results show that an instability exists and the power oscillation starting time and maximum peak power are different from the point kinetics results
Variational Formulation of 1-D Unsteady Compressible Flow in a Deforming Tube
Institute of Scientific and Technical Information of China (English)
Gaolian Liu; Yi Tao; Yingxue Liu
The variational principles for 1-D unsteady compressible flow in a deforming tube derived in a previous paper are improved essentially by reconstructing the initial/final-integral terms according to a new method suggested in a recent paper. As a result, the inherent shortcoming of variational principles of being unable to admit physically rational initial/final-value conditions in initial/boundary-value problems is successfully eliminated. Thus, a new theoretical basis for the time-space finite-element analysis is provided.
Monochromatic Neutron Tomography Using 1-D PSD Detector at Low Flux Research Reactor
Ashari, N. Abidin; Saleh, J. Mohamad; Abdullah, M. Zaid; Mohamed, A. Aziz; Azman, A.; Jamro, R.
This paper describes the monochromatic neutron tomography experiment using the 1-D Position Sensitive Neutron Detector (PSD) located at Nuclear Malaysia TRIGA MARK II Research reactor. Experimental work was performed using monochromatic neutron source from beryllium filter and HOPG crystal monochromator. The principal main aim of this experiment was to test the detector efficiency, image reconstruction algorithm and the usage of 0.5 nm monochromatic neutrons for the neutron tomography setup. Other objective includes gathering important parameters and features to characterize the system.
Analytical solution to the Riemann problem of 1D elastodynamics with general constitutive laws
Berjamin, H; Chiavassa, G; Favrie, N
Under the hypothesis of small deformations, the equations of 1D elastodynamics write as a 2 x 2 hyperbolic system of conservation laws. Here, we study the Riemann problem for convex and nonconvex constitutive laws. In the convex case, the solution can include shock waves or rarefaction waves. In the nonconvex case, compound waves must also be considered. In both convex and nonconvex cases, a new existence criterion for the initial velocity jump is obtained. Also, admissibility regions are determined. Lastly, analytical solutions are completely detailed for various constitutive laws (hyperbola, tanh and polynomial), and reference test cases are proposed.
Electronic and Transport Properties of Quasi-1D Wires of Biological Molecules
Oetzel, Björn; Matthes, Lars; Tandetzky, Falk; Ortmann, Frank; Bechstedt, Friedhelm; Hannewald, Karsten
In the search for organic materials with good charge-transport properties, artificial stacks of biological molecules are considered attractive candidates [1,2]. In this spirit, we present ab-initio DFT calculations of the structural, electronic, and quantum-transport properties of quasi-1D wires based on guanine and eumelanin molecules [3]. Hereby, a special focus is put on the results for the electronic bandwidths and the consequences for potential applications. [4pt] [1] R. di Felice et al., Phys. Rev. B 65, 045104 (2001) [0pt] [2] P. Meredith et al., Pigment Cell Res. 19, 572 (2006) [0pt] [3] B. Oetzel et al. (unpublished)
Injectable composites via functionalization of 1D nanoclays and biodegradable coupling with a polysaccharide hydrogel.
Del Buffa, Stefano; Rinaldi, Elia; Carretti, Emiliano; Ridi, Francesca; Bonini, Massimo; Baglioni, Piero
The use of injectable materials in minimally invasive surgical procedures could help in facing the bone diseases connected to the ageing of world population. To this aim, materials integrating the rheological properties of biocompatible polymers with the mechanical properties of 1D inorganic nanostructures represent promising scaffolds. Here we describe the preparation of hydrogel composites made of carboxymethyl cellulose (CMC) and halloysite nanotubes (HNT) as injectable materials for the local treatment of bone defects. The rheology and injectability of the materials reflects their structural properties, showing the possibility of successfully injecting the prepared composites over a large range of operative conditions. PMID:27281242
Synthesis, Characterization, and Application of 1-D Cerium Oxide Nanomaterials: A Review
Directory of Open Access Journals (Sweden)
Kuen-Song Lin
Full Text Available The present work provides a comprehensive overview of the recent progress of research work toward developing new one dimensional (1-D ceria (CeO2 nanomaterials. The review has been classified into three parts: the preparation procedures with identification of the existing different dimensional ceria nanomaterials, the formation mechanisms, and an analysis of their applications. From literature survey, it is inaugurated that the fundamental structures of the ceria nanomaterials constructively dominate their properties and applications. In addition, this work will also provide a perspective on the future technical trends for the development of different dimensional CeO2 nanomaterials.
Cold beam of isotopically pure Yb atoms by deflection using 1D-optical molasses
Rathod, KD; Singh, PK; Natarajan, Vasant
We demonstrate the generation of an isotopically pure beam of laser-cooled Yb atoms by deflection using 1D-optical molasses. Atoms in a collimated thermal beam are first slowed using a Zeeman slower. They are then subjected to a pair of molasses beams inclined at 45(a similar to) with respect to the slowed atomic beam. The slowed atoms are deflected and probed at a distance of 160 mm. We demonstrate the selective deflection of the bosonic isotope Yb-174 and the fermionic isotope Yb-171. Using...
Cold beam of isotopically pure Yb atoms by deflection using 1D-optical molasses
Rathod, K. D.; Singh, P. K.; Natarajan, Vasant
We demonstrate generation of an isotopically pure beam of laser-cooled Yb atoms by deflection using 1D-optical molasses. Atoms in a collimated thermal beam are first slowed using a Zeeman Slower. They are then subjected to a pair of molasses beams inclined at $45^\\circ$ with respect to the slowed atomic beam. The slowed atoms are deflected and probed at a distance of 160 mm. We demonstrate selective deflection of the bosonic isotope $^{174}$Yb, and the fermionic isotope $^{171}$Yb. Using a transient measurement after the molasses beams are turned on, we find a longitudinal temperature of 41 mK.
Cold beam of isotopically pure Yb atoms by deflection using 1D-optical molasses
Rathod, K D; Natarajan, Vasant
We demonstrate generation of an isotopically pure beam of laser-cooled Yb atoms by deflection using 1D-optical molasses. Atoms in a collimated thermal beam are first slowed using a Zeeman Slower. They are then subjected to a pair of molasses beams inclined at $45^\\circ$ with respect to the slowed atomic beam. The slowed atoms are deflected and probed at a distance of 160 mm. We demonstrate selective deflection of the bosonic isotope $^{174}$Yb, and the fermionic isotope $^{171}$Yb. Using a transient measurement after the molasses beams are turned on, we find a longitudinal temperature of 41 mK.
Quadratic gravity in (2+1)D with a topological Chern-Simons term
International Nuclear Information System (INIS)
Three-dimensional quadratic gravity, unlike general relativity in (2+1)D, is dynamically nontrivial and has a well behaved nonrelativistic potential. Here we analyse the changes that occur when a topological Chern-Simons term is added to this theory. It is found that the harmless massive scalar mode of the latter gives rise to a troublesome massive spin-0 ghost, while the massive spin-2 ghost is replaced by two massive physical particles both of spin 2. We also found that light deflection does not have the 'wrong sign' such as in the framework of three-dimensional quadratic gravity. (author)
Hair on non-extremal D1-D5 bound states
Roy, Pratik; Virmani, Amitabh
We consider a truncation of type IIB supergravity on four-torus where in addition to the Ramond-Ramond 2-form field, the Ramond-Ramond axion (w) and the NS-NS 2-form field (B) are also retained. In the (w, B) sector we construct a linearised perturbation carrying only left moving momentum on two-charge non-extremal D1-D5 geometries of Jejjala, Madden, Ross and Titchener. The perturbation is found to be smooth everywhere and normalizable. It is constructed by matching to leading order solutions of the perturbation equations in the inner and outer regions of the geometry.
Momentum-carrying waves on D1-D5 microstate geometries
Energy Technology Data Exchange (ETDEWEB)
Mathur, Samir D., E-mail: firstname.lastname@example.com [Department of Physics, Ohio State University, Columbus, OH 43210 (United States); Turton, David, E-mail: email@example.com [Department of Physics, Ohio State University, Columbus, OH 43210 (United States)
If one attempts to add momentum-carrying waves to a black string then the solution develops a singularity at the horizon; this is a manifestation of the 'no hair theorem' for black objects. However individual microstates of a black string do not have a horizon, and so the above theorem does not apply. We construct a perturbation that adds momentum to a family of microstates of the extremal D1-D5 string. This perturbation is analogous to the 'singleton' mode localized at the boundary of AdS; to leading order it is pure gauge in the AdS interior of the geometry.
Momentum-carrying waves on D1-D5 microstate geometries
Mathur, Samir D
If one attempts to add momentum-carrying waves to a black string then the solution develops a singularity at the horizon; this is a manifestation of the 'no hair theorem' for black objects. However individual microstates of a black string do not have a horizon, and so the above theorem does not apply. We construct a perturbation that adds momentum to a family of microstates of the extremal D1-D5 string. This perturbation is analogous to the 'singleton' mode localized at the boundary of AdS; to leading order it is pure gauge in the AdS interior of the geometry.
Multi-particle processes in $\\kappa$-Poincar\\'e inspired by 2+1D gravity
Kowalski-Glikman, Jerzy
Inspired by a Chern-Simons description of 2+1D gravity coupled to point particles we propose a new Lagrangian of a multiparticle system living in $\\kappa$-Minkowski/$\\kappa$-Poincar\\'e spacetime. We derive the dynamics of interacting particles with $\\kappa$-momentum space, alternative to the one proposed in the "principle of relative locality" literature. In this construction the locality of particle processes is naturally implemented, even for distant observers. In particular each particle process is characterized by a local deformed energy-momentum conservation law. On the other hand, the relation between non-causally-connected events still reflects the effects of deformed kinematics and relativity of locality.
Hair on non-extremal D1-D5 bound states
Roy, Pratik; Srivastava, Yogesh K.; Virmani, Amitabh
We consider a truncation of type IIB supergravity on four-torus where in addition to the Ramond-Ramond 2-form field, the Ramond-Ramond axion ( w) and the NS-NS 2-form field ( B) are also retained. In the ( w, B) sector we construct a linearised perturbation carrying only left moving momentum on two-charge non-extremal D1-D5 geometries of Jejjala, Madden, Ross and Titchener. The perturbation is found to be smooth everywhere and normalisable. It is constructed by matching to leading order solutions of the perturbation equations in the inner and outer regions of the geometry.
Maximizing 1D "like" implosion performance for inertial confinement fusion science
Energy Technology Data Exchange (ETDEWEB)
Kline, John L. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
While the march towards achieving indirectly driven inertial confinement fusion at the NIF has made great progress, the experiments show that multi-dimensional effects still dominate the implosion performance. Low mode implosion symmetry and hydrodynamic instabilities seed by capsule mounting features appear to be two key limiting factors for implosion performance. One reason these factors have a large impact on the performance of ICF implosions is the high convergence required to achieve high fusion gains. To tackle these problems, a predictable implosion platform is needed meaning experiments must trade-off high gain for performance. To this end, LANL has adopted three main approaches to develop a 1D implosion platform where 1D means high yield over 1D clean calculations. Taking advantage of the properties of beryllium capsules, a high adiabat, low convergence platform is being developed. The higher drive efficiency for beryllium enables larger case-to-capsule ratios to improve symmetry at the expense of drive. Smaller capsules with a high adiabat drive are expected to reduce the convergence and thus increase predictability. The second approach is liquid fuel layers using wetted foam targets. With liquid fuel layers, the initial mass in the hot spot can be controlled via the target fielding temperature which changes the liquid vapor pressure. Varying the initial hot spot mass via the vapor pressure controls the implosion convergence and minimizes the need to vaporize the dense fuel layer during the implosion to achieve ignition relevant hot spot densities. The last method is double shell targets. Unlike hot spot ignition, double shells ignite volumetrically. The inner shell houses the DT fuel and the convergence of this cavity is relatively small compared to hot spot ignition. Radiation trapping and the longer confinement times relax the conditions required to ignite the fuel. Key challenges for double shell targets are coupling the momentum of the outer shell to
Editing of CD1d-Bound Lipid Antigens by Endosomal Lipid Transfer Proteins
Zhou, Dapeng; Cantu, Carlos; Sagiv, Yuval; Schrantz, Nicolas; Kulkarni, Ashok B.; Qi, Xiaoyang; Mahuran, Don J.; Carlos R Morales; Grabowski, Gregory A.; Benlagha, Kamel; Savage, Paul; Bendelac, Albert; Teyton, Luc
It is now established that CD1 molecules present lipid antigens to T cells, although it is not clear how the exchange of lipids between membrane compartments and the CD1 binding groove is assisted. We report that mice deficient in prosaposin, the precursor to a family of endosomal lipid transfer proteins (LTP), exhibit specific defects in CD1d-mediated antigen presentation and lack Vα14 NKT cells. In vitro, saposins extracted monomeric lipids from membranes and from CD1, thereby promoting the...
TCTEX1D2 mutations underlie Jeune asphyxiating thoracic dystrophy with impaired retrograde intraflagellar transport
Schmidts, M.; Hou, Y; Cortes, C.R.; Mans, D. A.; Huber, C.; Boldt, K.; M. Patel; Van Reeuwijk, J; Plaza, J.M.; Beersum, S.E.C; Yap, Z.M.; Letteboer, S.J.F.; Taylor, S. P.; Herridge, W; Johnson, C A
ARTICLE Received 1 Oct 2014 | Accepted 31 Mar 2015 | Published 5 June 2015 TCTEX1D2 mutations underlie Jeune asphyxiating thoracic dystrophy with impaired retrograde intraflagellar transport Miriam Schmidts1,2,3,4,*, Yuqing Hou5,*, Claudio R. Corte´s6, Dorus A. Mans2,3, Celine Huber7, Karsten Boldt8, Mitali Patel1, Jeroen van Reeuwijk2,3, Jean-Marc Plaza9, Sylvia E.C. van Beersum2,3, Zhi Min Yap1, Stef J.F. Letteboer2,3, S Paige Taylor10, Warren Herridge11, Colin A. Johns...
Statistical properties of 1D spin glasses from first principles of classical mechanics
Gevorkyan, A. S.; Sahakyan, V. V.
We study the classical 1D Heisenberg spin glasses. Based on the Hamilton equations we obtained the system of recurrence equations which allows to perform node-by-node calculations of a spin-chain. It is shown that calculations from first principles of classical mechanics lead to NP hard problem, that however in the limit of the statistical equilibrium can be calculated by P algorithm. For the partition function of the ensemble a new representation is offered in the form of one-dimensional int...
Exact spin dynamics of inhomogeneous 1-d systems at high temperature
Danieli, E. P.; Pastawski, H. M.; Levstein, P. R.
The evaluation of spin excitation dynamics in finite 1-d systems of spins {1}/{2} with XY exchange interaction J acquired new interest because NMR experiments at high temperature ( kBT≫ J) confirmed the predicted spin wave behavior of mesoscopic echoes. In this work, we use the Jordan-Wigner transformation to obtain the exact dynamics of inhomogeneous chains and rings where the evolution is reduced to one-body dynamics. For higher dimensions, the spin excitations manifest many-body effects that can be interpreted as a simple dynamics of non-interacting fermions plus a decoherent process.
Thermal impedance at the interface of contacting bodies: 1-D examples solved by semi-derivatives
Directory of Open Access Journals (Sweden)
Hristov Jordan
Full Text Available Simple 1-D semi-infinite heat conduction problems enable to demonstrate the potential of the fractional calculus in determination of transient thermal impedances of two bodies with different initial temperatures contacting at the interface ( x = 0 at t = 0 . The approach is purely analytic and uses only semi-derivatives (half-time and semi-integrals in the Riemann-Liouville sense. The example solved clearly reveals that the fractional calculus is more effective in calculation the thermal resistances than the entire domain solutions.
Analysis of Flash Flood Routing by Means of 1D - Hydraulic Modelling
Tesfay Abraha, Zerisenay
This study was conducted at the mountainous catchment part of Batinah Region of the Sultanate of Oman called Al-Awabi watershed which is about 260km2 in area with about 40 Km long Wadi main channel. The study paper presents a proposed modeling approach and possible scenario analysis which uses 1D - hydraulic modeling for flood routing analysis; and the main tasks of this study work are (1) Model setup for Al-Awabi watershed area, (2) Sensitivity Analysis, and (3) Scenario Analysis on impacts ...
Cold beam of isotopically pure Yb atoms by deflection using 1D-optical molasses
Indian Academy of Sciences (India)
K D Rathod; P K Singh; Vasant Natarajan
We demonstrate the generation of an isotopically pure beam of laser-cooled Yb atoms by deflection using 1D-optical molasses. Atoms in a collimated thermal beam are first slowed using a Zeeman slower. They are then subjected to a pair of molasses beams inclined at 45° with respect to the slowed atomic beam. The slowed atoms are deflected and probed at a distance of 160 mm. We demonstrate the selective deflection of the bosonic isotope 174Yb and the fermionic isotope 171Yb. Using a transient measurement after the molasses beams are turned on, we find a longitudinal temperature of 41 mK.
Severe hypoglycemia and diabetic ketoacidosis among youth with type 1 diabetes in the T1D Exchange clinic registry
Severe hypoglycemia (SH) and diabetic ketoacidosis (DKA) are common serious acute complications of type 1 diabetes (T1D). The aim of this study was to determine the frequency of SH and DKA and identify factors related to their occurrence in the T1D Exchange pediatric and young adult cohort. The anal...
REFLA-1D/MODE3: a computer code for reflood thermo-hydrodynamic analysis during PWR-LOCA
International Nuclear Information System (INIS)
This manual describes the REFLA-1D/MODE3 reflood system analysis code. This code can solve the core thermo-hydrodynamics under forced flooding conditions and gravity feed conditions in a system similar to FLECHT-SET Phase A. This manual describes the REFLA-1D/MODE3 models and provides application information required to utilize the code. (author)
Identification of regions critical for the integrity of the TSC1-TSC2-TBC1D7 complex.
Directory of Open Access Journals (Sweden)
Arthur Jorge Santiago Lima
Full Text Available The TSC1-TSC2-TBC1D7 complex is an important negative regulator of the mechanistic target of rapamycin complex 1 that controls cell growth in response to environmental cues. Inactivating TSC1 and TSC2 mutations cause tuberous sclerosis complex (TSC, an autosomal dominant disorder characterised by the occurrence of benign tumours in various organs and tissues, notably the brain, skin and kidneys. TBC1D7 mutations have not been reported in TSC patients but homozygous inactivation of TBC1D7 causes megaencephaly and intellectual disability. Here, using an exon-specific deletion strategy, we demonstrate that some regions of TSC1 are not necessary for the core function of the TSC1-TSC2 complex. Furthermore, we show that the TBC1D7 binding site is encoded by TSC1 exon 22 and identify amino acid residues involved in the TSC1-TBC1D7 interaction.
Interfaces Supporting Surface Gap Soliton Ground States in the 1D Nonlinear Schroedinger Equation
Dohnal, Tomas; Plum, Michael; Reichel, Wolfgang
We consider the problem of verifying the existence of $H^1$ ground states of the 1D nonlinear Schr\\"odinger equation for an interface of two periodic structures: $$-u" +V(x)u -\\lambda u = \\Gamma(x) |u|^{p-1}u \\ {on} \\R$$ with $V(x) = V_1(x), \\Gamma(x)=\\Gamma_1(x)$ for $x\\geq 0$ and $V(x) = V_2(x), \\Gamma(x)=\\Gamma_2(x)$ for $x1$. The article [T. Dohnal, M. Plum and W. Reichel, "Surface Gap Soliton Ground States for the Nonlinear Schr\\"odinger Equation," \\textit{Comm. Math. Phys.} \\textbf{308}, 511-542 (2011)] provides in the 1D case an existence criterion in the form of an integral inequality involving the linear potentials $V_{1},V_2$ and the Bloch waves of the operators $-\\tfrac{d^2}{dx^2}+V_{1,2}-\\lambda$. We choose here the classes of piecewise constant and piecewise linear potentials $V_{1,2}$ and check this criterion for a set of parameter values. In the piecewise constant case the Bloch waves are calculated explicitly and in the piecewise linear case verified enclosures of the Bloch waves are computed ...
CD1d expression and invariant NKT cell responses in herpesvirus infections
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Rusung eTan
Full Text Available Invariant natural killer T (iNKT cells are a highly conserved subset of unconventional T lymphocytes that express a canonical, semi-invariant T cell receptor (TCR and surface markers shared with the natural killer cell lineage. iNKT cells recognize exogenous and endogenous glycolipid antigens restricted by non-polymorphic CD1d molecules, and are highly responsive to the prototypical agonist, α-galactosylceramide. Upon activation, iNKT cells rapidly coordinate signaling between innate and adaptive immune cells through the secretion of proinflammatory cytokines, leading to the maturation of antigen-presenting cells and expansion of antigen-specific CD4+ and CD8+ T cells. Because of their potent immunoregulatory properties, iNKT cells have been extensively studied and are known to play a pivotal role in mediating immune responses against microbial pathogens including viruses. Here, we review evidence that herpesviruses manipulate CD1d expression to escape iNKT cell surveillance and establish lifelong latency in humans. Collectively, published findings suggest that iNKT cells play critical roles in anti-herpesvirus immune responses and could be harnessed therapeutically to limit viral infection and viral-associated disease.
Unveiling the Role of CNTs on the Phase Formation of 1D Ferroelectrics
Mahajan, Amit
Carbon nanotubes (CNTs) have the potential to act as templates or bottom electrodes for three dimension (3D) capacitor arrays, which utilise one dimension (1D) ferroelectric nanostructures to increase memory size and density. However, growing a ferroelectric on the surface of CNTs is non-trivial. Here, we demonstrate that multi-walled (MW) CNTs decrease the time and temperature for formation of lead zirconium titanate Pb(Zr1-xTix)O3 (PZT) by ~100 ºC commensurate with a decrease in activation energy from 68±15 kJ/mol to 27±2 kJ/mol. As a consequence, monophasic PZT was obtained at 575 ºC for MWCNTs/PZT whereas for pure PZT traces of pyrochlore were still present at 650 ºC, where PZT phase formed due to homogeneous nucleation. The piezoelectric nature of MWCNT/PZT synthesised at 500 ºC for 1 h was proved. Although further work is required to prove the concept of 3D capacitor arrays, our result suggests that it is feasible to utilise MWCNTs as templates/electrodes for the formation of 1D PZT nano ferroelectrics.
1D self-assembly of chemisorbed thymine on Cu(110) driven by dispersion forces.
Temprano, I; Thomas, G; Haq, S; Dyer, M S; Latter, E G; Darling, G R; Uvdal, P; Raval, R
Adsorption of thymine on a defined Cu(110) surface was studied using reflection-absorption infrared spectroscopy (RAIRS), temperature programmed desorption (TPD), and scanning tunnelling microscopy (STM). In addition, density functional theory (DFT) calculations were undertaken in order to further understand the energetics of adsorption and self-assembly. The combination of RAIRS, TPD, and DFT results indicates that an upright, three-point-bonded adsorption configuration is adopted by the deprotonated thymine at room temperature. DFT calculations show that the upright configuration adopted by individual molecules arises as a direct result of strong O-Cu and N-Cu bonds between the molecule and the surface. STM data reveal that this upright thymine motif self-assembles into 1D chains, which are surprisingly oriented along the open-packed [001] direction of the metal surface and orthogonal to the alignment of the functional groups that are normally implicated in H-bonding interactions. DFT modelling of this system reveals that the molecular organisation is actually driven by dispersion interactions, which cause a slight tilt of the molecule and provide the major driving force for assembly into dimers and 1D chains. The relative orientations and distances of neighbouring molecules are amenable for π-π stacking, suggesting that this is an important contributor in the self-assembly process. PMID:25770505
A Review of Swarm-Based 1D/2D Signal Processing
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Horia Mihail Teodorescu
Full Text Available While swarming behavior, widely encountered in nature, has recently sparked numerous models and interest in domains as optimization, data clustering, and control, their application to signal processing remains sporadic. In this paper I provide a unitary treatment and a review of former results obtained in signal filtering and enhancement using swarms. General equations are presented for these procedures and stability issues are considered, with examples. The paper overviews several swarming model I introduced in previous papers and provides new evidence of the applicability of these models in signal processing. In all the models for 1D signal processing, the key idea is that the swarm hunts a prey that impersonates the filtered signal. In the 2D models, the signal (image represents the "landscape" over which the swarm moves at a distance, while the swarm interacts with the signal (landscape. I provide and discuss details of the underlying theory of the models for processing time-domain signals and images. While this paper partly follows and summarizes previous papers, it nevertheless includes supplementary theoretical and algorithmic considerations and new results for both 1D and 2D signal processing. Although following either biological models or physical models in swarm algorithms is not generally accepted for technical applications, we prefer to emphasize the analogies established by our biomimetic approach with these two groups of models.
Structure, electrochemical properties and capacitance performance of polypyrrole electrodeposited onto 1-D crystals of iridium complex
Wysocka-Żołopa, Monika; Winkler, Krzysztof
Composites of polypyrrole and one-dimensional iridium complex crystals [(C2H5)4N]0.55[IrCl2(CO)2] were prepared by in situ two-step electrodeposition. Initially, iridium complex crystals were formed during [IrCl2(CO)2]- complex oxidation. Next, pyrrole was electropolymerized on the surface of the iridium needles. The morphology of the composite was investigated by scanning and transmission electron microscopy. At positive potentials, the iridium complex crystals and the polypyrrole were oxidized. In aprotic solvents, oxidation of the iridium complex crystals resulted in their dissolution. In water containing tetra(n-butyl)ammonium chlorides, the 1-D iridium complex crystals were reversibly oxidized. The product of the iridium complex oxidation remained on the electrode surface in crystalline form. The iridium complex needles significantly influenced the redox properties of the polymer. The polypyrrole involved electrode processes become more reversible in presence of crystals of iridium complex. The current of polypyrrole oxidation was higher compared to that of pure polypyrrole and the capacitance properties of the polymer were significantly enhanced. A specific capacitance as high as 590 F g-1 was obtained for a composite of polypyrrole and 1-D crystals of the iridium complex in water containing tetra(n-butyl)ammonium chloride. This value is approximately twice as high as the capacitance of the pure polymer deposited onto the electrode surface.
Ident 1D - a novel software tool for an easy identification of material constitutive parameters
International Nuclear Information System (INIS)
Non-linear finite element computations make use of very sophisticated constitutive equations for description of materials behaviour. The first difficulty encountered by potential users is the gap existing between raw material characterisation on uniaxial specimens and the knowledge of the required equation's parameters. There are very few software for this particular task. IDENT 1D is a special software developed under Matlab language in our laboratory, which is able to provide a complete optimised parameters set for implemented models. The originality of IDENT 1D is that no initial estimation of the material parameters is requested of the user. Two main examples are described in this article: the Lemaitre and Chaboche creep law coupled with damage and a non unified cyclic law proposed by Contesti and Cailletaud with a separation of plastic and viscous strain terms which is called DDI model. For both laws, the identification method is completely described. Each method is then applied to a set of experimental data. In both cases, the results of the parameters identification show a very good agreement with experimental data. (authors)
Superdescendants of the D1D5 CFT and their dual 3-charge geometries
Energy Technology Data Exchange (ETDEWEB)
Giusto, Stefano [Dipartimento di Fisica ed Astronomia "Galileo Galilei", Università di Padova,Via Marzolo 8, 35131 Padova (Italy); I.N.F.N. Sezione di Padova,Via Marzolo 8, 35131 Padova (Italy); Russo, Rodolfo [Centre for Research in String Theory, School of Physics and Astronomy,Queen Mary University of London, Mile End Road, London, E1 4NS (United Kingdom); Laboratoire de Physique Théorique de L'Ecole Normale Supérieure,24 rue Lhomond, 75231 Paris cedex (France)
We describe how to obtain the gravity duals of semiclassical states in the D1-D5 CFT that are superdescendants of a class of RR ground states. On the gravity side, the configurations we construct are regular and asymptotically reproduce the 3-charge D1-D5-P black hole compactified on S{sup 1}×T{sup 4}. The geometries depend trivially on the T{sup 4} directions but non-trivially on the remaining 6D space. In the decoupling limit, they reduce to asymptotically AdS{sub 3}×S{sup 3}×T{sup 4} spaces that are dual to CFT states obtained by acting with (exponentials of) the operators of the superconformal algebra. As explicit examples, we generalise the solution first constructed in arXiv:1306.1745 and discuss another class of states that have a more complicated dual geometry. By using the free orbifold description of the CFT we calculate the average values for momentum and the angular momenta of these configurations. Finally we compare the CFT results with those obtained in the bulk from the asymptotically M{sup 1,4}×S{sup 1}×T{sup 4} region.
Performance studies on high pressure 1-D position sensitive neutron detectors
Indian Academy of Sciences (India)
S S Desai; A M Shaikh
The powder diffractometer and Hi-Q diffractometer at Dhruva reactor make use of five identical 1-D position sensitive detectors (PSDs) to scan scattering angles in the range 3° to 140°. In order to improve the overall throughput of these spectrometers, it is planned to install a bank of 15 high-efficiency and high-resolution PSDs arranged in three layers with five PSDs in each layer. With each high pressure PSD (3He 10 bar + Kr 2 bar) showing the efficiency gain of 1.8 at 1.2 Å, detector bank is expected to show overall gain of 5.5 times the present detection efficiency and reduction in data collection time by equivalent factor. The 1-D PSDs are developed in batches of five, and are characterized so that all PSDs operate at uniform parameters such as position resolution, uniformity of efficiency and linearity of response. Position spectrum indicates the differential position resolution to be ∼ 1 mm and integral position resolution to be 3–4 mm. Broadening of position spectrum at the extreme end of sensitive length of PSD is analysed using fine shift of the beam. Dependence of position resolution and dynamic range of output pulse on the input impedance of pre-amplifier is also presented.
1-D Air-snowpack modeling of atmospheric nitrous acid at South Pole during ANTCI 2003
Directory of Open Access Journals (Sweden)
W. Liao
Full Text Available A 1-D air-snowpack model of HONO has been developed and constrained by observed chemistry and meteorology data. The 1-D model includes molecular diffusion and mechanical dispersion, windpumping in snow, gas phase to quasi-liquid layer phase HONO transfer and quasi-liquid layer nitrate and interstitial air HONO photolysis. Photolysis of nitrate is important as a dominant HONO source inside the snowpack, however, the observed HONO emission from the snowpack was triggered mainly by the equilibrium between quasi liquid layer nitrite and firn air HONO deep down the snow surface (i.e. 30 cm below snow surface. The high concentration of HONO in the firn air is subsequently transported above the snowpack by diffusion and windpumping. The model uncertainties come mainly from lack of measurements and the interpretation of the QLL properties based on the bulk snow measurements. One critical factor is the ionic strength of QLL nitrite, which is estimated here by the bulk snow pH, nitrite concentration, and QLL to bulk snow volume ratio.
Bogoliubov coefficients for the twist operator in the D1D5 CFT
Energy Technology Data Exchange (ETDEWEB)
Carson, Zaq, E-mail: firstname.lastname@example.com; Mathur, Samir D., E-mail: email@example.com; Turton, David, E-mail: firstname.lastname@example.com
The D1D5 CFT is a holographic dual of a near-extremal black hole in string theory. The interaction in this theory involves a twist operator which joins together different copies of a free CFT. Given a large number of D1 and D5 branes, the effective length of the circle on which the CFT lives is very large. We develop a technique to study the effect of the twist operator in the limit where the wavelengths of excitations are short compared to this effective length, which we call the 'continuum limit'. The method uses Bogoliubov coefficients to compute the effect of the twist operator in this limit. For bosonic fields, we use the method to reproduce recent results describing the effect of the twist operator when it links together CFT copies with windings M and N, producing a copy of winding M+N. We also comment on possible generalizations of our results. The methods developed here may help in understanding the twist interaction at higher orders. This in turn should provide insight into the thermalization process in the D1D5 CFT, which gives a holographic description of black hole formation.
Thermodynamics of Large N Gauge Theories with Chemical Potentials in a 1/D Expansion
Morita, Takeshi
In order to understand thermodynamical properties of N D-branes with chemical potentials associated with R-symmetry charges, we study a one dimensional large N gauge theory (bosonic BFSS type model) as a first step. This model is obtained through a dimensional reduction of a 1+D dimensional SU(N) Yang-Mills theory and we use a 1/D expansion to investigate the phase structure. We find three phases in the \\mu-T plane. We also show that all the adjoint scalars condense at large D and obtain a mass dynamically. This dynamical mass protects our model from the usual perturbative instability of massless scalars in a non-zero chemical potential. We find that the system is at least meta-stable for arbitrary large values of the chemical potentials in D \\to \\infty limit. We also explore the existence of similar condensation in higher dimensional gauge theories in a high temperature limit. In 2 and 3 dimensions, the condensation always happens as in one dimensional case. On the other hand, if the dimension is higher than...
Thermodynamics of large N gauge theories with chemical potentials in a 1/ D expansion
Morita, Takeshi
In order to understand thermodynamical properties of N D-branes with chemical potentials associated with R-symmetry charges, we study a one dimensional large N gauge theory (bosonic BFSS type model) as a first step. This model is obtained through a dimensional reduction of a 1 + D dimensional SU( N) Yang-Mills theory and we use a 1 /D expansion to investigate the phase structure. We find three phases in the μ - T plane. We also show that all the adjoint scalars condense at large D and obtain a mass dynamically. This dynamical mass protects our model from the usual perturbative instability of massless scalars in a non-zero chemical potential. We find that the system is at least meta-stable for arbitrary large values of the chemical potentials in D → ∞ limit. We also explore the existence of similar condensation in higher dimensional gauge theories in a high temperature limit. In 2 and 3 dimensions, the condensation always happens as in one dimensional case. On the other hand, if the dimension is higher than 4, there is a critical chemical potential and the condensation happens only if the chemical potentials are below it.
Dynamical compactification of D-dimensional gravity coupled to antisymmetric tensors in a 1/D expansion
International Nuclear Information System (INIS)
The effective potential of components of the curl of an antisymmetric tensor coupled to gravity in D dimensions is evaluated in a 1/D expansion. For large D, only highest-rank propagators contribute to leading order, while multiloop diagrams are suppressed by phase-space factors. Divergences are regulated by a cut-off LAMBDA, that we interpret as the mass-breaking scale of a larger theory that is finite. As an application we consider the bosonic sector of D=11, N=1 supergravity. If the full theory is finite, then LAMBDA is msub(SUSY): the scale below which the fermion sector decouples. For m9sub(SUSY)>1/akappa2, (kappa2: the D=11 Newton's coupling, a approx.= O(1)) the 11-dimensional symmetric vacuum is unstable under compactification. For m9sub(SUSY)2, it is metastable. To leading order in 1/D, all gauge dependence cancels identically, while ghosts as well as the graviton decouple. (author)
A world-line framework for 1D Topological Conformal sigma-models
Baulieu, L; Toppan, F
We use world-line methods for pseudo-supersymmetry to construct $sl(2|1)$-invariant actions for the $(2,2,0)$ chiral and ($1,2,1)$ real supermultiplets of the twisted $D$-module representations of the $sl(2|1)$ superalgebra. The derived one-dimensional topological conformal $\\sigma$-models are invariant under nilpotent operators. The actions are constructed for both parabolic and hyperbolic/trigonometric realizations (with extra potential terms in the latter case). The scaling dimension $\\lambda$ of the supermultiplets defines a coupling constant, $2\\lambda+1$, the free theories being recovered at $\\lambda=-\\frac{1}{2}$. We also present, generalizing previous works, the $D$-module representations of one-dimensional superconformal algebras induced by ${\\cal N}=(p,q)$ pseudo-supersymmetry acting on $(k,n,n-k)$ supermultiplets. Besides $sl(2|1)$, we obtain the superalgebras $A(1,1)$, $D(2,1;\\alpha)$, $D(3,1)$, $D(4,1)$, $A(2,1)$ from $(p,q)= (1,1), (2,2), (3,3), (4,4), (5,1)$, at given $k,n$ and critical values ...
A world-line framework for 1D topological conformal σ-models
Baulieu, L.; Holanda, N. L.; Toppan, F.
We use world-line methods for pseudo-supersymmetry to construct sl(2|1)-invariant actions for the (2, 2, 0) chiral and (1, 2, 1) real supermultiplets of the twisted D-module representations of the sl(2|1) superalgebra. The derived one-dimensional topological conformal σ-models are invariant under nilpotent operators. The actions are constructed for both parabolic and hyperbolic/trigonometric realizations (with extra potential terms in the latter case). The scaling dimension λ of the supermultiplets defines a coupling constant, 2λ + 1, the free theories being recovered at λ = - /1 2 . We also present, generalizing previous works, the D-module representations of one-dimensional superconformal algebras induced by N = ( p , q ) pseudo-supersymmetry acting on (k, n, n - k) supermultiplets. Besides sl(2|1), we obtain the superalgebras A(1, 1), D(2, 1; α), D(3, 1), D(4, 1), A(2, 1) from (p, q) = (1, 1), (2, 2), (3, 3), (4, 4), (5, 1), at given k, n and critical values of λ.
Quasi-1D physics in metal-organic frameworks: MIL-47(V from first principles
Directory of Open Access Journals (Sweden)
Danny E. P. Vanpoucke
Full Text Available The geometric and electronic structure of the MIL-47(V metal-organic framework (MOF is investigated by using ab initio density functional theory (DFT calculations. Special focus is placed on the relation between the spin configuration and the properties of the MOF. The ground state is found to be antiferromagnetic, with an equilibrium volume of 1554.70 Å3. The transition pressure of the pressure-induced large-pore-to-narrow-pore phase transition is calculated to be 82 MPa and 124 MPa for systems with ferromagnetic and antiferromagnetic chains, respectively. For a mixed system, the transition pressure is found to be a weighted average of the ferromagnetic and antiferromagnetic transition pressures. Mapping DFT energies onto a simple-spin Hamiltonian shows both the intra- and inter-chain coupling to be antiferromagnetic, with the latter coupling constant being two orders of magnitude smaller than the former, suggesting the MIL-47(V to present quasi-1D behavior. The electronic structure of the different spin configurations is investigated and it shows that the band gap position varies strongly with the spin configuration. The valence and conduction bands show a clear V d-character. In addition, these bands are flat in directions orthogonal to VO6 chains, while showing dispersion along the the direction of the VO6 chains, similar as for other quasi-1D materials.
The LAPS Project : A live 1D Radiative-Convective Model to explore the possible climates of terrestrial planets and exoplanets.
Turbet, Martin; Forget, Francois; Schott, Cédric
The LAPS (Live Atmospheres-of-Planets Simulator) is a live 1D version of the LMD Global Climate Model that provides an accelerated and interactive simulation of the climate of terrestrial planets and exoplanets.This tool was designed for students to explore the «Classical Habitable Zone», defined as the range of orbital distances within which a planet can maintain liquid water on its surface. The model faithfully reproduces both the inner edge and the outer edge limits of the Habitable Zone, and their dependencies to the type of star and the gas composition.Furthermore, it provides a "hands on" experiment by showing how the surface and atmospheric temperatures as well as the profile of water vapor evolve through time when the external forcing (insolation, star spectrum, ...) or the planet (quantity of CO2, initial amount of water reservoir, ...) is modified.The tool is available at http://laps.lmd.jussieu.fr/ .
Adipocyte-specific CD1d-deficiency mitigates diet-induced obesity and insulin resistance in mice.
Satoh, Masashi; Hoshino, Miyuki; Fujita, Koki; Iizuka, Misao; Fujii, Satoshi; Clingan, Christopher S; Van Kaer, Luc; Iwabuchi, Kazuya
It has been shown that CD1d expression and glycolipid-reactive, CD1d-restricted NKT cells exacerbate the development of obesity and insulin resistance in mice. However, the relevant CD1d-expressing cells that influence the effects of NKT cells on the progression of obesity remain incompletely defined. In this study, we have demonstrated that 3T3-L1 adipocytes can present endogenous ligands to NKT cells, leading to IFN-γ production, which in turn, stimulated 3T3-L1 adipocytes to enhance expression of CD1d and CCL2, and decrease expression of adiponectin. Furthermore, adipocyte-specific CD1d deletion decreased the size of the visceral adipose tissue mass and enhanced insulin sensitivity in mice fed a high-fat diet (HFD). Accordingly, NKT cells were less activated, IFN-γ production was significantly reduced, and levels of adiponectin were increased in these animals as compared with control mice on HFD. Importantly, macrophage recruitment into the adipose tissue of adipocyte-specific CD1d-deficient mice was significantly blunted. These findings indicate that interactions between NKT cells and CD1d-expressing adipocytes producing endogenous NKT cell ligands play a critical role in the induction of inflammation and functional modulation of adipose tissue that leads to obesity. PMID:27329323
Retinoic acid regulates CD1d gene expression at the transcriptional level in human and rodent monocytic cells.
Chen, Qiuyan; Ross, A Catharine
CD1d belongs to a group of nonclassical antigen-presenting molecules that present glycolipid antigens and thereby activate natural killer T (NKT) cells, a subset of bifunctional T cells. Little is known so far regarding the expression and physiologic regulation of CD1d. Here we show that all-trans-retinoic acid (RA), the active metabolite of vitamin A, rapidly (1 hr after treatment) increases CD1d mRNA in human and rodent monocytic cells at a physiologic dose (10 nM). The induction is RA specific and RA receptor (RAR) dependent-RA and an RARalpha agonist, Am580, both had a pronounced positive effect, whereas the addition of RARalpha antagonist partially blocked the increase in CD1d mRNA induced by RA and Am580. The induction was also completely blocked by the presence of actinomycin D. A putative RA-response element was identified in the distal 5' flanking region of the CD1d gene, which binds nuclear retinoid receptors and was responsive to RA in both gel mobility shift assay and transient transfection assay in THP-1 cells. These results further confirmed the transcriptional regulation of RA in CD1d gene expression. Moreover, RA significantly increased alpha-galactosylceramide-induced spleen cell proliferation. These studies together provide evidence for a previously unknown mechanism of CD1d gene expression regulation by RA and suggest that RA is a significant modulator of NKT cell activation.
Lysophospholipid presentation by CD1d and recognition by a human Natural Killer T-cell receptor
Energy Technology Data Exchange (ETDEWEB)
López-Sagaseta, Jacinto; Sibener, Leah V.; Kung, Jennifer E.; Gumperz, Jenny; Adams, Erin J. (UC); (UW-MED)
Invariant Natural Killer T (iNKT) cells use highly restricted {alpha}{beta} T cell receptors (TCRs) to probe the repertoire of lipids presented by CD1d molecules. Here, we describe our studies of lysophosphatidylcholine (LPC) presentation by human CD1d and its recognition by a native, LPC-specific iNKT TCR. Human CD1d presenting LPC adopts an altered conformation from that of CD1d presenting glycolipid antigens, with a shifted {alpha}1 helix resulting in an open A pocket. Binding of the iNKT TCR requires a 7-{angstrom} displacement of the LPC headgroup but stabilizes the CD1d-LPC complex in a closed conformation. The iNKT TCR CDR loop footprint on CD1d-LPC is anchored by the conserved positioning of the CDR3{alpha} loop, whereas the remaining CDR loops are shifted, due in part to amino-acid differences in the CDR3{beta} and J{beta} segment used by this iNKT TCR. These findings provide insight into how lysophospholipids are presented by human CD1d molecules and how this complex is recognized by some, but not all, human iNKT cells.
Dynamics of the gas-liquid interfacial reaction of O(1D) with a liquid hydrocarbon.
Waring, Carla; King, Kerry L; Costen, Matthew L; McKendrick, Kenneth G
The dynamics of the gas-liquid interfacial reaction of the first electronically excited state of the oxygen atom, O((1)D), with the surface of a liquid hydrocarbon, squalane (C(30)H(62); 2,6,10,15,19,23-hexamethyltetracosane) has been studied experimentally. Translationally hot O((1)D) atoms were generated by 193 nm photolysis of a low pressure (nominally 1 mTorr) of N(2)O a short distance (mean = 6 mm) above a continually refreshed liquid squalane surface. Nascent OH (X(2)Π, v' = 0) reaction products were detected by laser-induced fluorescence (LIF) on the OH A(2)Σ(+)-X(2)Π (1,0) band at the same distance above the surface. The speed distribution of the recoiling OH was characterized by measuring the appearance profiles as a function of photolysis-probe delay for selected rotational levels, N'. The rotational (and, partially, fine-structure) state distributions were also measured by recording LIF excitation spectra at selected photolysis-probe delays. The OH v' = 0 rotational distribution is bimodal and can be empirically decomposed into near thermal (~300 K) and much hotter (~6000 K) Boltzmann-temperature components. There is a strong positive correlation between rotational excitation and translation energy. However, the colder rotational component still represents a significant fraction (~30%) of the fastest products, which have substantially superthermal speeds. We estimate an approximate upper limit of 3% for the quantum yield of OH per O((1)D) atom that collides with the surface. By comparison with established mechanisms for the corresponding reactions in the gas phase, we conclude that the rotationally and translationally hot products are formed via a nonstatistical insertion mechanism. The rotationally cold but translationally hot component is most likely produced by direct abstraction. Secondary collisions at the liquid surface of products of either of the previous two mechanisms are most likely responsible for the rotationally and translationally cold
Structural and population-based evaluations of TBC1D1 p.Arg125Trp.
Directory of Open Access Journals (Sweden)
Tom G Richardson
Full Text Available Obesity is now a leading cause of preventable death in the industrialised world. Understanding its genetic influences can enhance insight into molecular pathogenesis and potential therapeutic targets. A non-synonymous polymorphism (rs35859249, p.Arg125Trp in the N-terminal TBC1D1 phosphotyrosine-binding (PTB domain has shown a replicated association with familial obesity in women. We investigated these findings in the Avon Longitudinal Study of Parents and Children (ALSPAC, a large European birth cohort of mothers and offspring, and by generating a predicted model of the structure of this domain. Structural prediction involved the use of three separate algorithms; Robetta, HHpred/MODELLER and I-TASSER. We used the transmission disequilibrium test (TDT to investigate familial association in the ALSPAC study cohort (N = 2,292 mother-offspring pairs. Linear regression models were used to examine the association of genotype with mean measurements of adiposity (Body Mass Index (BMI, waist circumference and Dual-energy X-ray absorptiometry (DXA assessed fat mass, and logistic regression was used to examine the association with odds of obesity. Modelling showed that the R125W mutation occurs in a location of the TBC1D1 PTB domain that is predicted to have a function in a putative protein:protein interaction. We did not detect an association between R125W and BMI (mean per allele difference 0.27 kg/m(2 (95% Confidence Interval: 0.00, 0.53 P = 0.05 or obesity (odds ratio 1.01 (95% Confidence Interval: 0.77, 1.31, P = 0.96 in offspring after adjusting for multiple comparisons. Furthermore, there was no evidence to suggest that there was familial association between R125W and obesity (χ(2 = 0.06, P = 0.80. Our analysis suggests that R125W in TBC1D1 plays a role in the binding of an effector protein, but we find no evidence that the R125W variant is related to mean BMI or odds of obesity in a general population sample.
Higher-order local and non-local correlations for 1D strongly interacting Bose gas
Nandani, EJKP; Römer, Rudolf A.; Tan, Shina; Guan, Xi-Wen
The correlation function is an important quantity in the physics of ultracold quantum gases because it provides information about the quantum many-body wave function beyond the simple density profile. In this paper we first study the M-body local correlation functions, g M , of the one-dimensional (1D) strongly repulsive Bose gas within the Lieb-Liniger model using the analytical method proposed by Gangardt and Shlyapnikov (2003 Phys. Rev. Lett. 90 010401; 2003 New J. Phys. 5 79). In the strong repulsion regime the 1D Bose gas at low temperatures is equivalent to a gas of ideal particles obeying the non-mutual generalized exclusion statistics with a statistical parameter α =1-2/γ , i.e. the quasimomenta of N strongly interacting bosons map to the momenta of N free fermions via {k}i≈ α {k}iF with i=1,\\ldots ,N. Here γ is the dimensionless interaction strength within the Lieb-Liniger model. We rigorously prove that such a statistical parameter α solely determines the sub-leading order contribution to the M-body local correlation function of the gas at strong but finite interaction strengths. We explicitly calculate the correlation functions g M in terms of γ and α at zero, low, and intermediate temperatures. For M = 2 and 3 our results reproduce the known expressions for g 2 and g 3 with sub-leading terms (see for instance (Vadim et al 2006 Phys. Rev. A 73 051604(R); Kormos et al 2009 Phys. Rev. Lett. 103 210404; Wang et al 2013 Phys. Rev. A 87 043634). We also express the leading order of the short distance non-local correlation functions x}1)\\cdots {{{\\Psi }}}\\dagger ({x}M){{\\Psi }}({y}M)\\cdots {{\\Psi }}({y}1)> of the strongly repulsive Bose gas in terms of the wave function of M bosons at zero collision energy and zero total momentum. Here {{\\Psi }}(x) is the boson annihilation operator. These general formulas of the higher-order local and non-local correlation functions of the 1D Bose gas provide new insights into the many-body physics.
Full Waveform 3D Synthetic Seismic Algorithm for 1D Layered Anelastic Models
Schwaiger, H. F.; Aldridge, D. F.; Haney, M. M.
Numerical calculation of synthetic seismograms for 1D layered earth models remains a significant aspect of amplitude-offset investigations, surface wave studies, microseismic event location approaches, and reflection interpretation or inversion processes. Compared to 3D finite-difference algorithms, memory demand and execution time are greatly reduced, enabling rapid generation of seismic data within workstation or laptop computational environments. We have developed a frequency-wavenumber forward modeling algorithm adapted to realistic 1D geologic media, for the purpose of calculating seismograms accurately and efficiently. The earth model consists of N layers bounded by two halfspaces. Each layer/halfspace is a homogeneous and isotropic anelastic (attenuative and dispersive) solid, characterized by a rectangular relaxation spectrum of absorption mechanisms. Compressional and shear phase speeds and quality factors are specified at a particular reference frequency. Solution methodology involves 3D Fourier transforming the three coupled, second- order, integro-differential equations for particle displacements to the frequency-horizontal wavenumber domain. An analytic solution of the resulting ordinary differential system is obtained. Imposition of welded interface conditions (continuity of displacement and stress) at all interfaces, as well as radiation conditions in the two halfspaces, yields a system of 6(N+1) linear algebraic equations for the coefficients in the ODE solution. An optimized inverse 2D Fourier transform to the space domain gives the seismic wavefield on a horizontal plane. Finally, three-component seismograms are obtained by accumulating frequency spectra at designated receiver positions on this plane, followed by a 1D inverse FFT from angular frequency ω to time. Stress-free conditions may be applied at the top or bottom interfaces, and seismic waves are initiated by force or moment density sources. Examples reveal that including attenuation
Institute of Scientific and Technical Information of China (English)
一个月前佳能刚刚发布了APS-C规格旗舰单反EOS 7D,一个月后,佳能再次为我们带来了惊喜,全球同步发布采用APS-H规格的高端数码单反——EOS-1D Mark Ⅳ。作为2007年5月发布的EOS-1D Mark Ⅲ的继任机型,新推出的EOS-1D Mark Ⅳ采用全新的CMOS感光元件。
Institute of Scientific and Technical Information of China (English)
日前,佳能(中国)有限公司发布面向专业摄影师的数码单反相机EOS-1D Mark IV。EOS-1D Mark IV为EOS-1D/1Ds系列的第八款产品,是在新闻报道和体育摄影领域广受专业摄影师好评的EOS-1D Mark Ⅲ后继机型。
Synthesis and Crystal Structure of a 1-D Copper(Ⅱ) Polymer with 1-Hexylimidazole and Oxalate
Institute of Scientific and Technical Information of China (English)
A novel Cu(Ⅱ) complex has been prepared by means of self-assembly of CuCl2, 1-hexylimidazole L and oxalic acid (H2OX) in the presence of triethylamine, and structurally characterized by X-ray diffraction analysis. In complex 1, 1-D polymer chains are formed through pentacoordinated Cu(Ⅱ), oxalate and bridging chlorine atoms. In the crystal packing of 1, the imidazole ring head-to-tailπ-πstacking interactions exist between 1-D polymer chains and extend the 1-D polymer chains into 2-D supramolecular layers. The fluorescence emission spectra of L and 1 were described.
Quantum Diffusion on Molecular Tubes: Universal Scaling of the 1D to 2D Transition
Chuang, Chern; Lee, Chee Kong; Moix, Jeremy M.; Knoester, Jasper; Cao, Jianshu
The transport properties of disordered systems are known to depend critically on dimensionality. We study the diffusion coefficient of a quantum particle confined to a lattice on the surface of a tube, where it scales between the 1D and 2D limits. It is found that the scaling relation is universal and independent of the temperature, disorder, and noise parameters, and the essential order parameter is the ratio between the localization length in 2D and the circumference of the tube. Phenomenological and quantitative expressions for transport properties as functions of disorder and noise are obtained and applied to real systems: In the natural chlorosomes found in light-harvesting bacteria the exciton transfer dynamics is predicted to be in the 2D limit, whereas a family of synthetic molecular aggregates is found to be in the homogeneous limit and is independent of dimensionality.
Staggered grid leap-frog scheme for the (2+1)D Dirac equation
Hammer, René
A numerical scheme utilizing a grid which is staggered in both space and time is proposed for the numerical solution of the (2+1)D Dirac equation in presence of an external electromagnetic potential. It preserves the linear dispersion relation of the free Weyl equation for wave vectors aligned with the grid and facilitates the implementation of open (absorbing) boundary conditions via an imaginary potential term. This explicit scheme has second order accuracy in space and time. A functional for the norm is derived and shown to be conserved. Stability conditions are derived. Several numerical examples, ranging from generic to specific to textured topological insulator surfaces, demonstrate the properties of the scheme which can handle general electromagnetic potential landscapes.
Hamiltonian formalism for N=1, D=10 Yang--Mills coupled supergravity
International Nuclear Information System (INIS)
The canonical convariant formalism for N=1 D=10 matter-coupled supergravity is constructed and applied in both cases, when the Lagrangian density contains linear terms in the Riemann curvature, or the quadratic one. When in this coupled system the canonical formalism for higher curvature supergravities is considered, it is possible to show that the propagation torsion mechanism takes place. Starting from the first-order formalism with the Hamiltonian that contains a finite number of terms including higher curvature ones, the nonpolynomial structure of the second-order formalism of the supersymmetric transformation rules, as well as of the rheonomic equation, can be shown. This fact allows us to relate the higher curvature Hamiltonian formalism with the massless sector of effective superstring theories. copyright 1989 Academic Press, Inc
Analytical solution for 1D consolidation of unsaturated soil with mixed boundary condition
Institute of Scientific and Technical Information of China (English)
Zhen-dong SHAN; Dao-sheng LING; Hao-jiang DING
Based on consolidation equations proposed for unsaturated soil,an analytical solution for 1D consolidation of an unsaturated single-layer soil with nonhomogeneous mixed boundary condition is developed.The mixed boundary condition can be used for special applications,such as tests occur in laboratory.The analytical solution is obtained by assuming all material parameters remain constant during consolidation.In the derivation of the analytical solution,the nonhomogeneous boundary condition is first transformed into a homogeneous boundary condition.Then,the eigenfunction and eigenvalue are derived according to the consolidation equations and the new boundary condition.Finally,using the method of undetermined coefficients and the orthogonal relation of the eigenfunction,the analytical solution for the new boundary condition is obtained.The present method is applicable to various types of boundary conditions.Several numerical examples are provided to investigate the consolidation behavior of an unsaturated single-layer soil with mixed boundary condition.
MOL1D: a general purpose subroutine package for the numerical solution of partial differential equations
International Nuclear Information System (INIS)
MOL1D is a FORTRAN subroutine package for the method of lines solution for systems of initial-boundary-value partial differential equations in one space dimension. Using the package, a programer with limited experience in numerical analysis can accurately solve linear and nonlinear hyperbolic equations with or without discontinuities, linear and nonlinear parabolic equations (including those arising in reaction-diffusion equations), and elliptic boundary-value problems when posed as the stable time-independent solution of a parabolic equation. Systems are handled as easily as single equations, and a wide variety of boundary conditions can be accommodated, including most that arise in applications. The major advantage of the package is that initial-value problems can be solved accurately with a minimum of programing effort and with moderate computer cost. 4 figures, 1 table
Directed electromagnetic wave propagation in 1D metamaterial: Projecting operators method
Ampilogov, Dmitrii; Leble, Sergey
We consider a boundary problem for 1D electrodynamics modeling of a pulse propagation in a metamaterial medium. We build and apply projecting operators to a Maxwell system in time domain that allows to split the linear propagation problem to directed waves for a material relations with general dispersion. Matrix elements of the projectors act as convolution integral operators. For a weak nonlinearity we generalize the linear results still for arbitrary dispersion and derive the system of interacting right/left waves with combined (hybrid) amplitudes. The result is specified for the popular metamaterial model with Drude formula for both permittivity and permeability coefficients. We also discuss and investigate stationary solutions of the system related to some boundary regimes.
A 1-D evolutionary model for icy satellites, applied to Enceladus
Prialnik, Uri Malamud Dina
We develop a long-term 1-D evolution model for icy satellites that couples multiple processes: water migration and differentiation, geochemical reactions and silicate phase transitions, compaction by self-gravity, and ablation. The model further considers the following energy sources and sinks: tidal heating, radiogenic heating, geochemical energy released by serpentinization or absorbed by mineral dehydration, gravitational energy and insolation, and heat transport by conduction, convection, and advection. We apply the model to Enceladus, by guessing the initial conditions that would render a structure compatible with present-day observations, assuming the initial structure to have been homogeneous. Assuming the satellite has been losing water continually along its evolution, we postulate that it was formed as a more massive, more icy and more porous satellite, and gradually transformed into its present day state due to sustained long-term tidal heating. We consider several initial compositions and evolution...
Fep1d: a script for the analysis of reaction coordinates.
Banushkina, Polina V; Krivov, Sergei V
The dynamics of complex systems with many degrees of freedom can be analyzed by projecting it onto one or few coordinates (collective variables). The dynamics is often described then as diffusion on a free energy landscape associated with the coordinates. Fep1d is a script for the analysis of such one-dimensional coordinates. The script allows one to construct conventional and cut-based free energy profiles, to assess the optimality of a reaction coordinate, to inspect whether the dynamics projected on the coordinate is diffusive, to transform (rescale) the reaction coordinate to more convenient ones, and to compute such quantities as the mean first passage time, the transition path times, the coordinate dependent diffusion coefficient, and so forth. Here, we describe the implemented functionality together with the underlying theoretical framework.
Facile hydrothermal route to the controlled synthesis of -Fe2O3 1-D nanostructures
Indian Academy of Sciences (India)
Lixia Yang; Ying Liang; Hou Chen; Lingyan Kong; Wei Jiang
Single-crystalline -Fe2O3 1-D nanostructures can be obtained via a facile one-step hydrothermal synthetic route. It was found that the introduction of SnCl4 played a key role in determining the composition and morphology of -Fe2O3. The addition of SnCl4 favours the formation of Fe2O3 rather than FeOOH, and the morphology can be tuned from nanorod to double-shuttle as the increase of SnCl4 concentration. The products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and selectedarea electron diffraction (SAED). This simple method does not need any seed, catalyst, or template, thus is promising for large-scale and low-cost production.
Explicit analytical wave solutions of unsteady 1D ideal gas flow with friction and heat transfer
Institute of Scientific and Technical Information of China (English)
Several families of algebraically explicit analytical wavesolutions are derived for the unsteady 1D ideal gas flow with friction and heat-transfer, which include one family of travelling wave solutions, three families of standing wave solutions and one standing wave solution. \\{Among\\} them, the former four solution families contain arbitrary functions, so actually there are infinite analytical wave solutions having been derived. Besides their very important theoretical meaning, such analytical wave solutions can guide the development of some new equipment, and can be the benchmark solutions to promote the development of computational fluid dynamics. For example, we can use them to check the accuracy, convergence and effectiveness of various numerical computational methods and to improve the numerical computation skills such as differential schemes, grid generation ways and so on.
Exact solutions for correlation functions in some 1+1 D field theories with boundary
Freed, D E
We consider 1+1 D theories which are free everywhere except for cosine and magnetic interactions on the boundary. These theories arise in dissipative quantum systems, open string theory, and, in special cases, tunneling in quantum Hall systems. These boundary systems satisfy an approximate SL(2,Z) symmetry as a function of flux per unit cell and dissipation. At special multicritical points, they also satisfy a set of reparametrization Ward identities and have homogeneous, piecewise-linear correlation functions in momentum space. In this paper, we use these symmetries to find exact solutions for some of the correlation functions. We also comment on the form of the correlation functions in general, and verify that the SL(2,Z) duality transformation between different critical points is satisfied exactly in all cases where the full solution is known.
A 1-D modelling of streaming potential dependence on water content during drainage experiment in sand
Allègre, Vincent; Ackerer, Philippe; Jouniaux, Laurence; Sailhac, Pascal; 10.1111/j.1365-246X.2012.05371.x
The understanding of electrokinetics for unsaturated conditions is crucial for numerous of geophysical data interpretation. Nevertheless, the behaviour of the streaming potential coefficient C as a function of the water saturation Sw is still discussed. We propose here to model both the Richards' equation for hydrodynamics and the Poisson's equation for electrical potential for unsaturated conditions using 1-D finite element method. The equations are first presented and the numerical scheme is then detailed for the Poisson's equation. Then, computed streaming potentials (SPs) are compared to recently published SP measurements carried out during drainage experiment in a sand column. We show that the apparent measurement of DV / DP for the dipoles can provide the SP coefficient in these conditions. Two tests have been performed using existing models for the SP coefficient and a third one using a new relation. The results show that existing models of unsaturated SP coefficients C(Sw) provide poor results in term...
Statistics of scattered photons from a driven three-level emitter in 1D open space
Energy Technology Data Exchange (ETDEWEB)
Roy, Dibyendu [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Div. and Center for Nonlinear Studies; Bondyopadhaya, Nilanjan [Visva-Bharati University, Santiniketan (India). Integrated Science Education and Research Centre
We derive the statistics of scattered photons from a Λ- or ladder-type three-level emitter (3LE) embedded in a 1D open waveguide. The weak probe photons in the waveguide are coupled to one of the two allowed transitions of the 3LE, and the other transition is driven by a control beam. This system shows electromagnetically induced transparency (EIT) which is accompanied with the Autler-Townes splitting (ATS) at a strong driving by the control beam, and some of these effects have been observed recently. We show that the nature of second-order coherence of the transmitted probe photons near two-photon resonance changes from bunching to antibunching to constant as strength of the control beam is ramped up from zero to a higher value where the ATS appears.
Experimental investigations of heat transport dynamics in a 1D porous medium column
Pastore, Nicola; Cherubini, Claudia; Giasi, Concetta I.; Allegretti, Nicoletta Maria
A laboratory physical model has been set up to analyse the forced convective flow and the related heat transport dynamics through a 1d porous medium column. In particular, the experiments regard the observation of thermal breakthrough curves obtained through a continuous flow injection in correspondence of eight thermocouple positioned uniformly along a thermally isolated column of porous medium. The experiment has been conducted for different flow rates in order to investigate the critical issues regarding heat transport phenomena such as the influence of non-linear flow regime, the relationship between the thermal dispersion with the flow velocity and the validity of the local thermal equilibrium assumption between the fluid and solid phase. The results emphasize the magnitude of the errors of the commonly used assumptions in the numerical modelling of heat transport.
Experimental demonstration of an efficient number diagnostic for long 1D ion chains
Kamsap, Marius Romuald; Pedregosa-Gutierrez, J; Houssin, Marie; Knoop, Martina
Very long, one-dimensional (1D) ion chains are the basis for many applications, in particular in quantum information processing and reliable diagnostics are needed to quantify them. To that purpose, we have experimentally validated Dubin's model for very long ion chains [Phys. Rev. Lett. 71, 2753 (1993)]. This diagnostic allows to precisely determine the number of trapped ion with an accuracy of almost 1\\% without counting them, by measuring the ion-ion distance of the innermost particles, as well as the trapping potential along the ion chain direction. In our experiment, based on a 155 ion chain, the central 30 ions are measured to be equidistant to better than 2\\%, and we can determine the total number of trapped ions with a 4.5\\% uncertainty, completely dominated by a conservative estimation of the experimental characterisation of the trap.
Optical properties in 1D photonic crystal structure using Si/C{sub 60} multilayers
Energy Technology Data Exchange (ETDEWEB)
Chen Jing; Tang Jiyu; Chen Junfang [College of Physics and Telecommunication Engineering, South China Normal University, Guangzhou 510006 (China); Han Peide, E-mail: email@example.com, E-mail: email@example.com [College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024 (China)
The feasibility of using Si/C{sub 60} multilayer films as one-dimensional (1D) photonic band gap crystals was investigated by theoretical calculations using a transfer matrix method (TMM). The response has been studied both within and out of the periodic plane of Si/C{sub 60} multilayers. It is found that Si/C{sub 60} multilayer films show incomplete photonic band gap (PBG) behavior in the visible frequency range. The fabricated Si/C{sub 60} multilayers with two pairs of 70 nm C{sub 60} and 30 nm Si layers exhibit a PBG at central wavelength of about 600 nm, and the highest reflectivity can reach 99%. As a consequence, this photonic crystal may be important for fabricating a photonic crystal with an incomplete band gap in the visible frequency range.
Mechanisms and Kinetics of Radical Reaction of O(1D,3P) + HCN System
Institute of Scientific and Technical Information of China (English)
HUANG Yu-Cheng; DU Jin-Yan; JU Xue-Hai; YE Shi-Yong; ZHOU Tao
The reaction of HCN with O(1D, 3P) radical has been investigated by density functional theory (DFT) and ab initio methods. The stationary points on the reaction paths(reactants, intermediates and products) were optimized at the (U)B3LYP/aug-cc-pVTZ level.Single-point calculations were performed at the (U)QCISD(T)/aug-cc-pVTZ level for the optimized structures and all the total energies were corrected by zero-point energy. It is shown that there exist three competing mechanisms of oxygen attacking nitrogen O→N, oxygen attacking carbon O→C and oxygen attacking hydrogen O→H. The rate constants were obtained via Eyring transition-state theory in the temperature range of 600~2000 K. The linear relationship between lnk and 1/T was presented. The results show that path 1 is the main reaction channel and the product of NCO + H is predominant.
Smooth non-extremal D1-D5-P solutions as charged gravitational instantons
Chakrabarty, Bidisha; Virmani, Amitabh
We present an alternative and more direct construction of the non-supersymmetric D1-D5-P supergravity solutions found by Jejjala, Madden, Ross and Titchener. We show that these solutions --- with all three charges and both rotations turned on --- can be viewed as a charged version of the Myers-Perry instanton. We present an inverse scattering construction of the Myers-Perry instanton metric in Euclidean five-dimensional gravity. The angular momentum bounds in this construction turn out to be precisely the ones necessary for the smooth microstate geometries. We add charges on the Myers-Perry instanton using appropriate SO(4,4) hidden symmetry transformations. The full construction can be viewed as an extension and simplification of a previous work by Katsimpouri, Kleinschmidt and Virmani.
Dynamical Diffraction of Light from 1D Photonic Crystals with Sinusoidal Profile of Permittivity
International Nuclear Information System (INIS)
Bragg reflection and transmission spectra of the 1D photonic crystals characterized by a spatially sinusoidal profile of permittivity are studied as a function of the crystal-plate thickness. Applicability of the dynamical theory of diffraction in describing such spectra is considered. In the framework of the dynamical theory, we (i) calculated and analysed the reflection and transmission spectra for oblique incidence of polarized light, (ii) computed the spectra making use of the transfer matrix technique, and (iii) compared quantitatively the results of the two approaches. As a result, the analytical dynamical theory of diffraction is found to be correct in calculating the Bragg spectra in the vicinity of single photonic band-gap when the plate thickness is equal to the integer number of the spatial periods, or the permittivity is symmetric about the middle plane of the structure
Surface-modified Wannier-Stark states in a 1D optical lattice
Maury, A; Gorza, M -P; Lambrecht, A; Guérout, R
We study the energy spectrum of atoms trapped in a vertical 1D optical lattice in close proximity to a reflective surface. We propose an effective model to describe the interaction between the atoms and the surface at any distance. Our model includes the long-range Casimir-Polder potential together with a short-range Lennard-Jones potential, which are considered non-perturbatively with respect to the optical lattice potential. We find an intricate energy spectrum which contains a pair of loosely-bound states localized close to the surface in addition to a surface-modified Wannier-Stark ladder at long distances. Atomic interferometry involving those loosely-bound atom-surface states is proposed to probe the adsorption dynamics of atoms on mirrors.
Magnetodielectric and Metalomagnetic 1D Photonic Crystals Homogenization: ε-μ Local Behavior
Directory of Open Access Journals (Sweden)
J. I. Rodríguez Mora
Full Text Available A theory for calculating the effective optic response of photonic crystals with metallic and magnetic inclusions is reported, for the case when the wavelength of the electromagnetic fields is much larger than the lattice constant. The theory is valid for any type of Bravais lattice and arbitrary form of inclusions in the unitary cell. An equations system is obtained for macroscopic magnetic field and magnetic induction components expanding microscopic electromagnetic fields in Bloch waves. Permittivity and permeability effective tensors are obtained comparing the equations system with an anisotropic nonlocal homogenous medium. In comparison with other homogenization theories, this work uses only two tensors: nonlocal permeability and permittivity. The proposal showed here is based on the use of permeability equations, which are exact and very simple. We present the explicit form of these tensors in the case of binary 1D photonic crystals.
DC voltage profile of a 1D pumped wire with two dynamical and one static impurities
International Nuclear Information System (INIS)
In this work we study the behavior of the voltage profile of a 1D quantum wire with an impurity when transport is induced by two ac voltages that oscillating with a phase lag define a quantum pump. The voltage profile sensed along the wire by the voltage probe, that we assume weakly coupled to the system, exhibits a Friedel's oscillations structure inside the region delimited by the position of the two ac voltages that induce transport. On the other hand, outside this region the oscillations are suppressed. Using perturbation theory in the coupling constant of the voltage probe we derived analytical expressions for the DC current valid for the adiabatic regime. We also compare our analytical results with the exact numerical calculations using Keldysh non-equilibrium Green's functions formalism.
Pressure Sensor via Optical Detection Based on a 1D Spin Transition Coordination Polymer
Directory of Open Access Journals (Sweden)
Cătălin M. Jureschi
Full Text Available We have investigated the suitability of using the 1D spin crossover coordination polymer [Fe(4-(2'-hydroxyethyl-1,2,4-triazole3]I2∙H2O, known to crossover around room temperature, as a pressure sensor via optical detection using various contact pressures up to 250 MPa. A dramatic persistent colour change is observed. The experimental data, obtained by calorimetric and Mössbauer measurements, have been used for a theoretical analysis, in the framework of the Ising-like model, of the thermal and pressure induced spin state switching. The pressure (P-temperature (T phase diagram calculated for this compound has been used to obtain the P-T bistability region.
Quantum propagation and confinement in 1D systems using the transfer-matrix method
International Nuclear Information System (INIS)
The aim of this article is to provide some Matlab scripts to the teaching community in quantum physics. The scripts are based on the transfer-matrix formalism and offer a very efficient and versatile tool to solve problems of a physical object (electron, proton, neutron, etc) with one-dimensional (1D) stationary potential energy. Resonant tunnelling through a multiple-barrier or confinement in wells of various shapes is particularly analysed. The results are quantitatively discussed with semiconductor heterostructures, harmonic and anharmonic molecular vibrations, or neutrons in a gravity field. Scripts and other examples (hydrogen-like ions and transmission by a smooth variation of potential energy) are available freely at http://www-loa.univ-lille1.fr/~pujol in three languages: English, French and Spanish. (paper)
Analysis of silicon solar cell degradation in space using PC-1D
Energy Technology Data Exchange (ETDEWEB)
Moreno, E.G. (IMEC, Leuven (Belgium) DEE (UPC), Barcelona (Spain)); Demesmaeker, E.; Ghannam, M.; Nijs, J. (DEE (UPC), Barcelona (Spain))
This work presents a computation method to evaluate the life expectance of cells in space. The effects of the radiation environment are taken into account as a reduction of carrier lifetime. This reduction is calculated for each particle type as a function of the incident energy and the traveled depth inside the cell. Afterwards the calculated lifetimes are supplied to the PC-1D in order to obtain the electrical characteristics of the cell. The method allows one to calculate the equivalent damage relative to 1 MeV electrons of the different particles in the space environment. But its main feature lies in the direct calculation of the cell degradation by adding the contribution to lifetime reduction of each particle type. Results on efficiency degradation versus time in a circular orbit of 4630 km and 90deg inclination are shown for different cover glass thicknesses. (orig.).
Classification of phases of 1D spin chains with commuting Hamiltonians
Beigi, Salman
We consider the class of spin Hamiltonians on a 1D chain with periodic boundary conditions that are (i) translational invariant, (ii) commuting and (iii) scale invariant, where by the latter we mean that the ground state degeneracy is independent of the system size. We show that the ground state degeneracy is the only parameter that determines the phases of these Hamiltonians. We then characterize the low energy excitations by first making the assumption that there is no excitation of unit energy, and consequently show that all elementary excitations (of energy 2) come from the action of some string-type operator on the ground state which creates two quasi-particle excitations at the endpoints of the string. Our main tool in this paper is the idea of Bravyi and Vyalyi (2003) in using the representation theory of finite dimensional C*-algebras to study commuting Hamiltonians.
Quantum propagation and confinement in 1D systems using the transfer-matrix method
Pujol, Olivier; Carles, Robert; Pérez, José-Philippe
The aim of this article is to provide some Matlab scripts to the teaching community in quantum physics. The scripts are based on the transfer-matrix formalism and offer a very efficient and versatile tool to solve problems of a physical object (electron, proton, neutron, etc) with one-dimensional (1D) stationary potential energy. Resonant tunnelling through a multiple-barrier or confinement in wells of various shapes is particularly analysed. The results are quantitatively discussed with semiconductor heterostructures, harmonic and anharmonic molecular vibrations, or neutrons in a gravity field. Scripts and other examples (hydrogen-like ions and transmission by a smooth variation of potential energy) are available freely at http://www-loa.univ-lille1.fr/˜pujol in three languages: English, French and Spanish.
Holographic description of non-supersymmetric orbifolded D1-D5-P solutions
Chakrabarty, Bidisha; Virmani, Amitabh
Non-supersymmetric black hole microstates are of great interest in the context of the black hole information paradox. We identify the holographic description of the general class of non-supersymmetric orbifolded D1-D5-P supergravity solutions found by Jejjala, Madden, Ross and Titchener. This class includes both completely smooth solutions and solutions with conical defects, and in the near-decoupling limit these solutions describe degrees of freedom in the cap region. The CFT description involves a general class of states obtained by fractional spectral flow in both left-moving and right-moving sectors, generalizing previous work which studied special cases in this class. We compute the massless scalar emission spectrum and emission rates in both gravity and CFT and find perfect agreement, thereby providing strong evidence for our proposed identification. We also investigate the physics of ergoregion emission as pair creation for these orbifolded solutions. Our results represent the largest class of non-supe...
Recursive Estimation of Gauss-Markov Random Fields Indexed over 1-D Space
Vats, Divyanshu
This paper presents optimal recursive estimators for vector valued Gauss-Markov random \\emph{fields} taking values in $\\R^M$ and indexed by (intervals of) $\\R$ or $\\Z$. These 1-D fields are often called reciprocal processes. They correspond to two point boundary value fields, i.e., they have boundary conditions given at the end points of the indexing interval. To obtain the recursive estimators, we derive two classes of recursive representations for reciprocal processes. The first class transforms the Gaussian reciprocal process into a Gauss-Markov \\emph{process}, from which we derive forward and backwards recursive representations. The second representation folds the index set and transforms the original \\emph{field} taking values in $\\R^M$ into a Markov \\emph{process} taking values in $\\R^{2M}$. The folding corresponds to recursing the reciprocal process from the boundary points and telescoping inwards. From these recursive representations, Kalman filters and recursive smoothers are promptly derived.
Optimal modeling of 1D azimuth correlations in the context of Bayesian inference
De Kock, Michiel B; Trainor, Thomas A
Analysis and interpretation of spectrum and correlation data from high-energy nuclear collisions is currently controversial because two opposing physics narratives derive contradictory implications from the same data-one narrative claiming collision dynamics is dominated by dijet production and projectile-nucleon fragmentation, the other claiming collision dynamics is dominated by a dense, flowing QCD medium. Opposing interpretations seem to be supported by alternative data models, and current model-comparison schemes are unable to distinguish between them. There is clearly need for a convincing new methodology to break the deadlock. In this study we introduce Bayesian Inference (BI) methods applied to angular correlation data as a basis to evaluate competing data models. For simplicity the data considered are projections of 2D angular correlations onto 1D azimuth from three centrality classes of 200 GeV Au-Au collisions. We consider several data models typical of current model choices, including Fourier seri...
A Stochastic Wavelet Finite Element Method for 1D and 2D Structures Analysis
Directory of Open Access Journals (Sweden)
Xingwu Zhang
Full Text Available A stochastic finite element method based on B-spline wavelet on the interval (BSWI-SFEM is presented for static analysis of 1D and 2D structures in this paper. Instead of conventional polynomial interpolation, the scaling functions of BSWI are employed to construct the displacement field. By means of virtual work principle and BSWI, the wavelet finite elements of beam, plate, and plane rigid frame are obtained. Combining the Monte Carlo method and the constructed BSWI elements together, the BSWI-SFEM is formulated. The constructed BSWI-SFEM can deal with the problems of structural response uncertainty caused by the variability of the material properties, static load amplitudes, and so on. Taking the widely used Timoshenko beam, the Mindlin plate, and the plane rigid frame as examples, numerical results have demonstrated that the proposed method can give a higher accuracy and a better constringency than the conventional stochastic finite element methods.
Evolution of Matter Wave Interference of Bose-Condensed Gas in a 1D Optical Lattice
Institute of Scientific and Technical Information of China (English)
XU Zhi-Jun; ZHANG Dong-Mei
For a Bose-condensed gas in a combined potential consisting of an axially-symmetric harmonic magnetic trap and one-dimensional (1D) optical lattice, using the mean-field Gross-Pitaevskii (G-P) equation and the propagator method, we obtain the analytical result of the order parameter for matter wave interference at any time. The evolution of the interference pattern under a variation of the relative phase △φ between successive subcondensates trapped on an optical lattices is also studied. For △φ = π, the interference pattern is symmetric with two sharp peaks, which are symmetrically located on a straight line on both sides of a vacant central peak and moving apart from each other. This work is in agreement with available experimental results.
General equation for directed Electromagnetic Pulse Propagation in 1D metamaterial: Projecting Operators Method
Ampilogov, Dmitrii
We consider a boundary problem for 1D electrodynamics modeling of a pulse propagation in a metamaterial medium. We build and apply projecting operators to a Maxwell system in time domain that allows to split the linear propagation problem to directed waves for a material relations with general dispersion. Matrix elements of the projectors act as convolution integral operators. For a weak nonlinearity we generalize the linear results still for arbitrary dispersion and derive the system of interacting right/left waves with combined (hybrid) amplitudes. The result is specified for the popular metamaterial model with Drude formula for both permittivity and permeability coefficients. We also discuss and investigate stationary solutions of the system related to some boundary regimes.
Light transport behaviours in quasi-1D disordered waveguides composed of random photonic lattices
Xu, Yuchen; Lin, Yujun; Zhu, Heyuan
We present a numerical study on the light transport properties which are modulated by the disorder strength in quasi-one-dimensional disordered waveguide which consists of periodically arranged scatterers with random dielectric constant. The transport mean free path is found to stay inversely proportional to the square of the relative fluctuation of the dielectric constant as in the 1D and 2D cases but with . The transport properties of light through a sample with a fixed size can be modulated from ballistic to localized regime as well, and a generalized scaling function is defined to determine the light transport status in such a sample. The calculation of the diffusion coefficient and the energy density profile of the most transmitted eigenchannel clearly exhibits the transition of transport behaviour from diffusion to localization.
Institute of Scientific and Technical Information of China (English)
The model of 1D unsteady channel flow combined with the Kalmanfilter for real-time channel flood forecasting was attempted in this study. The suitable upstream and downstream boundary conditions were suggested. The system equation was given by the linearization of the finitedifference equations of the mass conservation and momentum equations as well as the boundary conditions. In the Kalman filter updating model, because the number of measurement variable is less then that of state-space variables, the measurement error covariance matrix could be estimated in real time through the innovation sequence, and the system error covariance matrix needs to be estimated preliminarily. A real example of flood forecasting in the Huaihe River was given to explain how the method works. The results show that the model is reasonable and effective.
Mt Response of a 1d Earth Model Employing the Born Approximation with Variable Background Conductivities
Tejero, A.; Chavez, R. E.
The Born approximation method has been commonly employed to study the electromagnetic field response. Other interpretative techniques have benn employed based upon the Born Approximation, like the extended Born approximation (EBA). This method employs the total field, instead of the primary field. Also, the Quasi Linear Approximation method (QLA) is an extension of EVA. In the present work, we propose an alternative technique, which employs the Born Approximation using variable background conductivities (BAVBC). The Green function is represented as a Born perturbation of zero order. Such that, the reference medium conductivity is a parameter selected according the working frequency. A similar procedure has been reported for stratified 1D-earth seismic models. This technique (BAVBC) has been applied to model computational models with reasonable results, as compared with available computational packages in the market. This method permits variations in the conductivity contrast of up to 80%, which provides solutions with 30% error, with respect of the analytical solution.
Quantum phase transition of light in a 1-D photon-hopping-controllable resonator array
Wu, Chun-Wang; Deng, Zhi-Jiao; Dai, Hong-Yi; Chen, Ping-Xing; Li, Cheng-Zu
We give a concrete experimental scheme for engineering the insulator-superfluid transition of light in a one-dimensional (1-D) array of coupled superconducting stripline resonators. In our proposed architecture, the on-site interaction and the photon hopping rate can be tuned independently by adjusting the transition frequencies of the charge qubits inside the resonators and at the resonator junctions, respectively, which permits us to systematically study the quantum phase transition of light in a complete parameter space. By combining the techniques of photon-number-dependent qubit transition and fast read-out of the qubit state using a separate low-Q resonator mode, the statistical property of the excitations in each resonator can be obtained with a high efficiency. An analysis of the various decoherence sources and disorders shows that our scheme can serve as a guide to coming experiments involving a small number of coupled resonators.
Forward Compton scattering by /sup 2//sub 1/D and /sup 4//sub 2/He nuclei
Energy Technology Data Exchange (ETDEWEB)
Avakyan, V.S.; Aleksanyan, A.S.; Gasparyan, A.O.; Gevorkyan, S.R.; Pikhtelev, R.N.
Experimental values of differential cross sections for forward Compton scattering by /sup 2//sub 1/D and /sup 4//sub 2/He nuclei are given. They are obtained from analysis of data on Compton scattering by nucleons and nuclei. Taking into account the Glauber corrections, estimates for Ref /sub 1//sup 0/ and the ratio Vertical Barf /sup 0//sub 2/Vertical Bar/sup 2//Vertical Barf /sub 1//sup 0/Vertical Bar/sup 2/ are obtained from experimental data in the energy range k = 2--6 GeV. Within the experimental errors the values for Ref/sup 0//sub 1/ coincide with theoretical values obtained by means of dispersion relations. Contribution from the spin-flip amplitude in the energy range considered is < or =5%.
Canonical quantization of nonlocal theories related to bosonization in 2 + 1D
International Nuclear Information System (INIS)
We present a canonical formulation for theories whose actions contain non-integer powers of the d'Alembertian operator and which were recently shown to play a central role in 2 + 1D bosonization. We show that these theories possess an infinite number of constraints and use the Dirac method in order to obtain the classical brackets. The casual and classical Green functions are obtained and their meaning in terms of field expectation values is discussed. The Wightman functions are introduced and shown to lead to the microcausality principle. A mode expansion for the field is obtained. This permits the reobtention of the Wightman functions as vacuum expectation values of products of the basic fields. Creation and annihilation operators are naturally introduced but, as shown, they are not related to definite mass particle states. This is also confirmed by the spectral decomposition of the Wightman functions. (author). 16 refs, 1 fig
System for Digital 1D-Image Processing with 1024 Pixel CCD Sensor
Directory of Open Access Journals (Sweden)
J. Misun
Full Text Available The conception of system for digital 1D-images processing with digital CCD camera is presented. The system is created from these three basic parts: the digital CCD camera with linear image sensor CCD L133C, 8-bit interface and a personal computer. The scanning digital CCD camera generated a video signals, which are processed in the analog signal processor. The output signal is continually converted to 8-bit data words in A/D converter. This data words maybe transfer over a bus driver to the operation memory of personal computer, by setting one of the three work regimes of digital CCD camera. Some application possibilities and basic technical parameters of this system are given.
A new subgenotype 2.1d isolates of classical swine fever virus in China, 2014.
Zhang, Hongliang; Leng, Chaoliang; Feng, Liping; Zhai, Hongyue; Chen, Jiazeng; Liu, Chunxiao; Bai, Yun; Ye, Chao; Peng, Jinmei; An, Tongqing; Kan, Yunchao; Cai, Xuehui; Tian, Zhijun; Tong, Guangzhi
The lapinized attenuated vaccine against classical swine fever (CSF) has been used in China for over half a century and has generally prevented large-scale outbreaks in recent years. However, since late 2014, a large number of new cases of CSF were detected in many immunized pig farms in China. Several of these CSV viruses were isolated and characterized. Phylogenetic and genomic sequence analyses indicate that these new isolates, as well as some reference isolates, form a new subgenotype named 2.1d, and share several consistent molecular characteristics. Since these new isolates emerged in disparate geographic regions within 5 months, this suggests that these isolates may be widespread. Given that current vaccines do not appear to provide effective protection against this new subgenotype, further investigation of these strains is urgently needed. PMID:26031602
1-D and 2-D Probabilistic Inversions of Fault Zone Guided Waves
Gulley, A.; Eccles, J. D.; Kaipio, J. P.; Malin, P. E.
Fault Zone Guided Waves (FZGWs) are seismic coda that are trapped by the low velocity damage zone of faults. Inversions of these phases can be carried out using their measured dispersion and a Bayesian probability approach. This method utilises a Markov chain Monte Carlo which allows uncertainties and trade-offs to be quantified. Accordingly we have developed a scheme that estimates the dispersion curve and amplitude response variability from a FZGW record. This method allows the computation of both the point estimates and the covariance of the dispersion curve. The subsequent estimation of fault zone parameters is then based on a Gaussian model for the dispersion curve. We then show that inversions using FZGW dispersion data can only resolve fault zone velocity contrast and fault zone width - it leaves densities, absolute country rock velocities and the earthquake location unresolved. We show that they do however significantly affect the estimated fault zone velocities and widths. As these parameters cannot be resolved, we allow for their effects on the estimates of fault zone width and velocity contrast by using the Bayesian approximation error method. We show that using this method reduces computational time from days to minutes and the associated loss of accuracy is insignificant compared to carrying out the inversion on all parameters. We have extended our scheme to 2-D using 1-D slices. The Bayesian approximation error methodology is further employed to provide a 'correction term' with uncertainty for the 1-D slice approximation. We investigate these features with both synthetic data and FZGW data from the Alpine Fault of New Zealand.
Analytical solutions for some defect problems in 1D hexagonal and 2D octagonal quasicrystals
Indian Academy of Sciences (India)
X Wang; E Pan
We study some typical defect problems in one-dimensional (1D) hexagonal and two-dimensional (2D) octagonal quasicrystals. The first part of this investigation addresses in detail a uniformly moving screw dislocation in a 1D hexagonal piezoelectric quasicrystal with point group 6. A general solution is derived in terms of two functions 1, 2, which satisfy wave equations, and another harmonic function 3. Elementary expressions for the phonon and phason displacements, strains, stresses, electric potential, electric fields and electric displacements induced by the moving screw dislocation are then arrived at by employing the obtained general solution. The derived solution is verified by comparison with existing solutions. Also obtained in this part of the investigation is the total energy of the moving screw dislocation. The second part of this investigation is devoted to the study of the interaction of a straight dislocation with a semi-infinite crack in an octagonal quasicrystal. Here the crack penetrates through the solid along the period direction and the dislocation line is parallel to the period direction. We first derive a general solution in terms of four analytic functions for plane strain problem in octagonal quasicrystals by means of differential operator theory and the complex variable method. All the phonon and phason displacements and stresses can be expressed in terms of the four analytic functions. Then we derive the exact solution for a straight dislocation near a semi-infinite crack in an octagonal quasicrystal, and also present the phonon and phason stress intensity factors induced by the straight dislocation and remote loads.
Cocaine inhibits dopamine D2 receptor signaling via sigma-1-D2 receptor heteromers.
Directory of Open Access Journals (Sweden)
Gemma Navarro
Full Text Available Under normal conditions the brain maintains a delicate balance between inputs of reward seeking controlled by neurons containing the D1-like family of dopamine receptors and inputs of aversion coming from neurons containing the D2-like family of dopamine receptors. Cocaine is able to subvert these balanced inputs by altering the cell signaling of these two pathways such that D1 reward seeking pathway dominates. Here, we provide an explanation at the cellular and biochemical level how cocaine may achieve this. Exploring the effect of cocaine on dopamine D2 receptors function, we present evidence of σ1 receptor molecular and functional interaction with dopamine D2 receptors. Using biophysical, biochemical, and cell biology approaches, we discovered that D2 receptors (the long isoform of the D2 receptor can complex with σ1 receptors, a result that is specific to D2 receptors, as D3 and D4 receptors did not form heteromers. We demonstrate that the σ1-D2 receptor heteromers consist of higher order oligomers, are found in mouse striatum and that cocaine, by binding to σ1 -D2 receptor heteromers, inhibits downstream signaling in both cultured cells and in mouse striatum. In contrast, in striatum from σ1 knockout animals these complexes are not found and this inhibition is not seen. Taken together, these data illuminate the mechanism by which the initial exposure to cocaine can inhibit signaling via D2 receptor containing neurons, destabilizing the delicate signaling balance influencing drug seeking that emanates from the D1 and D2 receptor containing neurons in the brain.
Evaluation of the Transport of Natural Radioactive Materials in Large Lysimeters Using Hydrus-1D
Pontedeiro, E.; Cipriani, M.; van Genuchten, M.; Simunek, J.
The mining industry in Brazil often uses raw materials that contain relatively high concentrations of naturally occurring radioactive materials (referred to as NORM). Ores of relatively low grade typically are used to produce refined metals of high purity (e.g., Nb, Ta, Sn, and Au) using pyrometallurgic processes. The final waste is a slag rich in natural radioactive contaminants (the U and Th decay series), which are then usually deposited in industrial landfills. To study the long-term fate and transport of radionuclides leached from the NORM wastes, several large (3 m deep) lysimeters were constructed at the Pocos de Caldas Laboratory of the Brazilian Nuclear Energy Commision (CNEN). The lysimeters were packed with surface soils and slags from one of the mining sites in South East Brazil. Main purpose of our lysimeter experiments was to follow the dissolution and transport of radionuclides from the slags under natural climatic conditions. Leaching rates and radionuclide concentrations of the effluent were observed during a three-year time period. A variety of physical and chemical properties of the soils and slags (including laboratory batch equilibrium sorption values) were also determined. The data were analyzed using several computer software packages, including the STANMOD code for analytical modeling of decay chain transport during steady flow, the HYDRUS-1D code for variably-saturated flow and the transport of multiple solutes, and the HP1 code for a more comprehensive analysis of the geochemistry involved. In this presentation we describe the experimental setup and provide preliminary results of the theoretical analyses, especially those using HYDRUS-1D.
FORest Canopy Atmosphere Transfer (FORCAsT) 1.0: a 1-D model of biosphere-atmosphere chemical exchange
Ashworth, K.; Chung, S. H.; Griffin, R. J.; Chen, J.; Forkel, R.; Bryan, A. M.; Steiner, A. L.
Biosphere-atmosphere interactions play a critical role in governing atmospheric composition, mediating the concentrations of key species such as ozone and aerosol, thereby influencing air quality and climate. The exchange of reactive trace gases and their oxidation products (both gas and particle phase) is of particular importance in this process. The FORCAsT (FORest Canopy Atmosphere Transfer) 1-D model is developed to study the emission, deposition, chemistry and transport of volatile organic compounds (VOCs) and their oxidation products in the atmosphere within and above the forest canopy. We include an equilibrium partitioning scheme, making FORCAsT one of the few canopy models currently capable of simulating the formation of secondary organic aerosols (SOAs) from VOC oxidation in a forest environment. We evaluate the capability of FORCAsT to reproduce observed concentrations of key gas-phase species and report modeled SOA concentrations within and above a mixed forest at the University of Michigan Biological Station (UMBS) during the Community Atmosphere-Biosphere Interactions Experiment (CABINEX) field campaign in the summer of 2009. We examine the impact of two different gas-phase chemical mechanisms on modelled concentrations of short-lived primary emissions, such as isoprene and monoterpenes, and their oxidation products. While the two chemistry schemes perform similarly under high-NOx conditions, they diverge at the low levels of NOx at UMBS. We identify peroxy radical and alkyl nitrate chemistry as the key causes of the differences, highlighting the importance of this chemistry in understanding the fate of biogenic VOCs (bVOCs) for both the modelling and measurement communities.
Effects of GWAS-associated genetic variants on lncRNAs within IBD and T1D candidate loci
DEFF Research Database (Denmark)
Mirza, Aashiq H; Kaur, Simranjeet; Brorsson, Caroline A;
Long non-coding RNAs are a new class of non-coding RNAs that are at the crosshairs in many human diseases such as cancers, cardiovascular disorders, inflammatory and autoimmune disease like Inflammatory Bowel Disease (IBD) and Type 1 Diabetes (T1D). Nearly 90% of the phenotype-associated single......, we systemically identified all annotated IBD and T1D loci-associated lncRNAs, and mapped nominally significant GWAS/ImmunoChip SNPs for IBD and T1D within these lncRNAs. Additionally, we identified tissue-specific cis-eQTLs, and strong linkage disequilibrium (LD) signals associated with these SNPs....... We explored sequence and structure based attributes of these lncRNAs, and also predicted the structural effects of mapped SNPs within them. We also identified lncRNAs in IBD and T1D that are under recent positive selection. Our analysis identified putative lncRNA secondary structure-disruptive SNPs...
Institute of Scientific and Technical Information of China (English)
FloEFD与Flowmaster结合起来可以作为一个1D-3D CFD应用的最佳组合,帮助设计工程师更加快速地实现更完美的产品设计开发。除了FloEFD,其他3D CFD工具也可通过MCPPI接口转移到Flowmaster进行1D CFD分析。
Identification of T1D susceptibility genes within the MHC region by combining protein interaction networks and SNP genotyping data
DEFF Research Database (Denmark)
Brorsson, C.; Hansen, Niclas Tue; Hansen, Kasper Lage;
genes. We have developed a novel method that combines single nucleotide polymorphism (SNP) genotyping data with protein-protein interaction (ppi) networks to identify disease-associated network modules enriched for proteins encoded from the MHC region. Approximately 2500 SNPs located in the 4 Mb MHC...... of additional risk genes for T1D. Combining genetic data with knowledge about functional pathways provides new insight into mechanisms underlying T1D....
Development of a 1D thermal-hydraulic analysis code for once-through steam generator in SMRs using straight tubes
Energy Technology Data Exchange (ETDEWEB)
Park, Youngjae; Kim, Iljin; Kim, Hyungdae [Kyung Hee University, Yongin (Korea, Republic of)
Diverse integral/small-modular reactors (SMRs) have been developed. Once-through steam generator (OTSG) which generates superheated steam without steam separator and dryer was used in the SMRs to reduce volume of steam generator. It would be possible to design a new steam generator with best estimate thermal-hydraulic codes such as RELAP and MARS. However, it is not convenience to use the general purpose thermal-hydraulic analysis code to design a specific component of nuclear power plants. A widely used simulation tool for thermal-hydraulic analysis of drum-type steam generators is ATHOS, which allows 3D analysis. On the other hand, a simple 1D thermal-hydraulic analysis code might be accurate enough for the conceptual design of OTSG. In this study, thermal-hydraulic analysis code for conceptual design of OTSG was developed using 1D homogeneous equilibrium model (HEM). A benchmark calculation was also conducted to verify and validate the prediction accuracy of the developed code by comparing with the analysis results with MARS. Finally, conceptual design of OTSG was conducted by the developed code. A simple 1D thermal-hydraulic analysis code was developed for the purpose of conceptual design OTSG for SMRs. A set of benchmark calculations was conducted to verify and validate the analysis accuracy of the developed code by comparing results obtained with a best-estimated thermal-hydraulic analysis code, MARS. Finally, analysis of two different OTSG design concepts with superheating and recirculation was demonstrated using the developed code.
1维石墨烯光子晶体的电磁吸收特性%Electromagnetic absorption characteristics of 1-D graphene photonic crystals
Institute of Scientific and Technical Information of China (English)
宁仁霞; 刘少斌; 章海锋; 孔祥鲲; 卞博锐
为了研究1维石墨烯光子晶体在可见光波段的吸收特性,采用传输矩阵的方法进行了理论分析和数值仿真,得到了1维石墨烯吸收特性与石墨烯层数、缺陷层介质厚度、电磁波模式有关的结果。结果表明,增加石墨烯层数时,对波长为556 nm左右的绿光的吸收作用明显增强;缺陷层介质厚度增加时会引起吸收峰的增加;在TE模式下,入射角对石墨烯光子晶体吸收特性影响较小。该研究结果为1维石墨烯光子晶体吸收器的设计提供了理论依据。%In order to study the absorption characterisctics of 1-D graphene photonic crystal in the visible band, theoretical analysis and numerical simulation were conducted by using transfer matrix method. The dependance of absorption characterisctics of 1-D graphene on graphene layers, dielectric thickness of defect layers, and electromagnetic mode were obtained.The results show that the absorption with green light of wavelength of about 556nm is enhanced significantly with the increasing of the layers of graphene.The absorption peak will increase with the increasing of dielectric thickness of defect layer.In the TE mode, the angle of incidence has a little effect on the absorption characterisctics of graphene photonic crystal.The results provide the theoretical basis for the study of 1-D graphene photonic crystal absorbers.
Light-directing chiral liquid crystal nanostructures: from 1D to 3D.
Bisoyi, Hari Krishna; Li, Quan
Endowing external, remote, and dynamic control to self-organized superstructures with desired functionalities is a principal driving force in the bottom-up nanofabrication of molecular devices. Light-driven chiral molecular switches or motors in liquid crystal (LC) media capable of self-organizing into optically tunable one-dimensional (1D) and three-dimensional (3D) superstructures represent such an elegant system. As a consequence, photoresponsive cholesteric LCs (CLCs), i.e., self-organized 1D helical superstructures, and LC blue phases (BPs), i.e., self-organized 3D periodic cubic lattices, are emerging as a new generation of multifunctional supramolecular 1D and 3D photonic materials in their own right because of their fundamental academic interest and technological significance. These smart stimuli-responsive materials can be facilely fabricated from achiral LC hosts by the addition of a small amount of a light-driven chiral molecular switch or motor. The photoresponsiveness of these materials is a result of both molecular interaction and geometry changes in the chiral molecular switch upon light irradiation. The doped photoresponsive CLCs undergo light-driven pitch modulation and/or helix inversion, which has many applications in color filters, polarizers, all-optical displays, optical lasers, sensors, energy-saving smart devices, and so on. Recently, we have conceptualized and rationally synthesized different light-driven chiral molecular switches that have very high helical twisting powers (HTPs) and exhibit large changes in HTP in different states, thereby enabling wide phototunability of the systems by the addition of very small amounts of the molecular switches into commercially available achiral LCs. The light-driven chiral molecular switches are based on well-recognized azobenzene, dithienylcyclopentene, and spirooxazine derivatives. We have demonstrated high-resolution and lightweight photoaddressable displays without patterned electronics on
Development of a 1 D hydrodynamic habitat model for the Hippopotamus amphibious as basis for sustainable exploitation of hydroelectric power
Manful, D. Y.; Kaule, G.; Wieprecht, S.; Rees, J.; Hu, W.
Hydroelectric Power (HEP) is proving to be a good alternative to carbon based energy. In the past hydropower especially large scale hydro attracted significant criticism as a result of its impact on the environment. A new breed of hydroelectric dam is in the offing. The aim is to have as little a footprint as possible on the environment in both pre and post construction phases and thus minimize impact on biodiversity whilst producing clean renewable energy. The Bui dam is 400 MW scheme currently under development on the Black Volta River in the Bui national park in Ghana. The reservoir created by the Bui barrage is expected to impact (through inundation) the habitat of two species of hippos know to exist in the park, the Hippopotamus amphibius and the Choeropsis liberiensis. Computer-based models present a unique opportunity to assess quantitatively the impact of the new reservoir on the habitat of the target species in this case the H. amphibious. Until this undertaking, there were very few studies documenting the habitat of the H. amphibious let alone model it. The work and subsequent presentation will show the development of a habitat model for the Hippopotamus amphibius. The Habitat Information retrieval Program based on Streamflow Analysis, in short HIPStrA, is a one dimensional (1D) in-stream, spatially explicit hybrid construct that combines physico-chemical evidence and expert knowledge to forecast river habitat suitability (Hs) for the Hippopotamus amphibius. The version of the model presented is specifically developed to assess the impact of a reservoir created by a hydroelectric dam on potential dwelling areas in the Bui gorge for hippos. Accordingly, this version of HIPStrA simulates a special reservoir suitability index (Rsi), a metric that captures the"hippo friendliness" of any lake or reservoir. The impact of measured and simulated flood events as well as low flows, representing extreme events is also assessed. Recommendations are made for the
Recent Advances in the Modeling of the Transport of Two-Plasmon-Decay Electrons in the 1-D Hydrodynamic Code LILAC
Delettrez, J. A.; Myatt, J. F.; Yaakobi, B.
The modeling of the fast-electron transport in the 1-D hydrodynamic code LILAC was modified because of the addition of cross-beam-energy-transfer (CBET) in implosion simulations. Using the old fast-electron with source model CBET results in a shift of the peak of the hard x-ray (HXR) production from the end of the laser pulse, as observed in experiments, to earlier in the pulse. This is caused by a drop in the laser intensity of the quarter-critical surface from CBET interaction at lower densities. Data from simulations with the laser plasma simulation environment (LPSE) code will be used to modify the source algorithm in LILAC. In addition, the transport model in LILAC has been modified to include deviations from the straight-line algorithm and non-specular reflection at the sheath to take into account the scattering from collisions and magnetic fields in the corona. Simulation results will be compared with HXR emissions from both room-temperature plastic and cryogenic target experiments. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.
Analytic 1D pn junction diode photocurrent solutions following ionizing radiation and including time-dependent changes in the carrier lifetime.
Energy Technology Data Exchange (ETDEWEB)
Axness, Carl L.; Keiter, Eric Richard; Kerr, Bert (New Mexico Tech, Socorro, NM)
Circuit simulation tools (e.g., SPICE) have become invaluable in the development and design of electronic circuits in radiation environments. These codes are often employed to study the effect of many thousands of devices under transient current conditions. Device-scale simulation tools (e.g., MEDICI) are commonly used in the design of individual semiconductor components, but require computing resources that make their incorporation into a circuit code impossible for large-scale circuits. Analytic solutions to the ambipolar diffusion equation, an approximation to the carrier transport equations, may be used to characterize the transient currents at nodes within a circuit simulator. We present new transient 1D excess carrier density and photocurrent density solutions to the ambipolar diffusion equation for low-level radiation pulses that take into account a finite device geometry, ohmic fields outside the depleted region, and an arbitrary change in the carrier lifetime due to neutron irradiation or other effects. The solutions are specifically evaluated for the case of an abrupt change in the carrier lifetime during or after, a step, square, or piecewise linear radiation pulse. Noting slow convergence of the raw Fourier series for certain parameter sets, we use closed-form formulas for some of the infinite sums to produce 'partial closed-form' solutions for the above three cases. These 'partial closed-form' solutions converge with only a few tens of terms, which enables efficient large-scale circuit simulations.
Assessing the habitability of planets with Earth-like atmospheres with 1D and 3D climate modeling
Godolt, M.; Grenfell, J. L.; Kitzmann, D.; Kunze, M.; Langematz, U.; Patzer, A. B. C.; Rauer, H.; Stracke, B.
Context. The habitable zone (HZ) describes the range of orbital distances around a star where the existence of liquid water on the surface of an Earth-like planet is in principle possible. The applicability of one-dimensional (1D) climate models for the estimation of the HZ boundaries has been questioned by recent three-dimensional (3D) climate studies. While 3D studies can calculate the water vapor, ice albedo, and cloud feedback self-consistently and therefore allow for a deeper understanding and the identification of relevant climate processes, 1D model studies rely on fewer model assumptions and can be more easily applied to the large parameter space possible for extrasolar planets. Aims: We evaluate the applicability of 1D climate models to estimate the potential habitability of Earth-like extrasolar planets by comparing our 1D model results to those of 3D climate studies in the literature. We vary the two important planetary properties, surface albedo and relative humidity, in the 1D model. These depend on climate feedbacks that are not treated self-consistently in most 1D models. Methods: We applied a cloud-free 1D radiative-convective climate model to calculate the climate of Earth-like planets around different types of main-sequence stars with varying surface albedo and relative humidity profile. We compared the results to those of 3D model calculations available in the literature and investigated to what extent the 1D model can approximate the surface temperatures calculated by the 3D models. Results: The 1D parameter study results in a large range of climates possible for an Earth-sized planet with an Earth-like atmosphere and water reservoir at a certain stellar insolation. At some stellar insolations the full spectrum of climate states could be realized, i.e., uninhabitable conditions due to surface temperatures that are too high or too low as well as habitable surface conditions, depending only on the relative humidity and surface albedo assumed. When
Communication: Studies of the Lennard-Jones fluid in 2, 3, and 4 dimensions highlight the need for a liquid-state 1/d expansion.
Costigliola, Lorenzo; Schrøder, Thomas B; Dyre, Jeppe C
The recent theoretical prediction by Maimbourg and Kurchan [e-print arXiv:1603.05023 (2016)] that for regular pair-potential systems the virial potential-energy correlation coefficient increases towards unity as the dimension d goes to infinity is investigated for the standard 12-6 Lennard-Jones fluid. This is done by computer simulations for d = 2, 3, 4 going from the critical point along the critical isotherm/isochore to higher density/temperature. In both cases the virial potential-energy correlation coefficient increases significantly. For a given density and temperature relative to the critical point, with increasing number of dimension the Lennard-Jones system conforms better to the hidden-scale-invariance property characterized by high virial potential-energy correlations (a property that leads to the existence of isomorphs in the thermodynamic phase diagram, implying that it becomes effectively one-dimensional in regard to structure and dynamics). The present paper also gives the first numerical demonstration of isomorph invariance of structure and dynamics in four dimensions. Our findings emphasize the need for a universally applicable 1/d expansion in liquid-state theory; we conjecture that the systems known to obey hidden scale invariance in three dimensions are those for which the yet-to-be-developed 1/d expansion converges rapidly. PMID:27334147
Communication: Studies of the Lennard-Jones fluid in 2, 3, and 4 dimensions highlight the need for a liquid-state 1/d expansion
Costigliola, Lorenzo; Schrøder, Thomas B.; Dyre, Jeppe C.
The recent theoretical prediction by Maimbourg and Kurchan [e-print arXiv:1603.05023 (2016)] that for regular pair-potential systems the virial potential-energy correlation coefficient increases towards unity as the dimension d goes to infinity is investigated for the standard 12-6 Lennard-Jones fluid. This is done by computer simulations for d = 2, 3, 4 going from the critical point along the critical isotherm/isochore to higher density/temperature. In both cases the virial potential-energy correlation coefficient increases significantly. For a given density and temperature relative to the critical point, with increasing number of dimension the Lennard-Jones system conforms better to the hidden-scale-invariance property characterized by high virial potential-energy correlations (a property that leads to the existence of isomorphs in the thermodynamic phase diagram, implying that it becomes effectively one-dimensional in regard to structure and dynamics). The present paper also gives the first numerical demonstration of isomorph invariance of structure and dynamics in four dimensions. Our findings emphasize the need for a universally applicable 1/d expansion in liquid-state theory; we conjecture that the systems known to obey hidden scale invariance in three dimensions are those for which the yet-to-be-developed 1/d expansion converges rapidly.
Swift observations of the 2006 outburst of the recurrent nova RS Ophiuchi: II. 1D hydrodynamical models of wind driven shocks
Vaytet, N M H; Bode, M F
Following the early Swift X-ray observations of the latest outburst of the recurrent nova RS Ophiuchi in February 2006 (Paper I), we present new 1D hydrodynamical models of the system which take into account all three phases of the remnant evolution. The models suggest a novel way of modelling the system by treating the outburst as a sudden increase then decrease in wind mass-loss rate and velocity. The differences between this wind model and previous Primakoff-type simulations are described. A more complex structure, even in 1D, is revealed through the presence of both forward and reverse shocks, with a separating contact discontinuity. The effects of radiative cooling are investigated and key outburst parameters such as mass-loss rate, ejecta velocity and mass are varied. The shock velocities as a function of time are compared to the ones derived in Paper I. We show how the manner in which the matter is ejected controls the evolution of the shock and that for a well-cooled remnant, the shock deceleration ra...
Hyperbranched quasi-1D nanostructures for solid-state dye-sensitized solar cells.
Passoni, Luca; Ghods, Farbod; Docampo, Pablo; Abrusci, Agnese; Martí-Rujas, Javier; Ghidelli, Matteo; Divitini, Giorgio; Ducati, Caterina; Binda, Maddalena; Guarnera, Simone; Li Bassi, Andrea; Casari, Carlo Spartaco; Snaith, Henry J; Petrozza, Annamaria; Di Fonzo, Fabio
In this work we demonstrate hyperbranched nanostructures, grown by pulsed laser deposition, composed of one-dimensional anatase single crystals assembled in arrays of high aspect ratio hierarchical mesostructures. The proposed growth mechanism relies on a two-step process: self-assembly from the gas phase of amorphous TiO2 clusters in a forest of tree-shaped hierarchical mesostructures with high aspect ratio; oriented crystallization of the branches upon thermal treatment. Structural and morphological characteristics can be optimized to achieve both high specific surface area for optimal dye uptake and broadband light scattering thanks to the microscopic feature size. Solid-state dye sensitized solar cells fabricated with arrays of hyperbranched TiO2 nanostructures on FTO-glass sensitized with D102 dye showed a significant 66% increase in efficiency with respect to a reference mesoporous photoanode and reached a maximum efficiency of 3.96% (among the highest reported for this system). This result was achieved mainly thanks to an increase in photogenerated current directly resulting from improved light harvesting efficiency of the hierarchical photoanode. The proposed photoanode overcomes typical limitations of 1D TiO2 nanostructures applied to ss-DSC and emerges as a promising foundation for next-generation high-efficiency solid-state devices comprosed of dyes, polymers, or quantum dots as sensitizers.
Intra-chain superexchange couplings in quasi-1D 3d transition-metal magnetic compounds
Xiang, Hongping; Tang, Yingying; Zhang, Suyun; He, Zhangzhen
The electronic structure and magnetic properties of the quasi-1D transition-metal borates PbMBO4 (M = Ti, V, Cr, Mn, Fe, Co) have been investigated by density functional theory, including electronic correlation. The results evidence PbCrBO4 and PbFeBO4 as antiferromagnetic (AFM) semiconductors (intra-chain AFM and inter-chain FM) and PbMnBO4 as a ferromagnetic (FM) semiconductor (both intra- and inter-chain FM) in accordance with experimental observations. For non-synthesized PbTiBO4, PbVBO4, and PbCoBO4, the ground-state magnetic structures are paramagnetic, FM, and paramagnetic, respectively. In this series of compounds, there are two kinds of superexchange couplings dominating their magnetic properties, i.e. the direction M–M delocalization superexchange and indirect M–O–M correlation superexchange. For PbMBO4 with M 3+ d n , n ⩽ 3 (M = V and Cr), the main intra-chain spin coupling is the M–M t 2g–t 2g direct delocalization superexchange, while for PbMBO4 with M 3+ d n , n > 3 (M = Mn and Fe), the main intra-chain spin coupling is the near 90° M–O–M e g–p–e g indirect correlation superexchange.
Symmetric discontinuous Galerkin methods for 1-D waves Fourier analysis, propagation, observability and applications
Marica, Aurora
This work describes the propagation properties of the so-called symmetric interior penalty discontinuous Galerkin (SIPG) approximations of the 1-d wave equation. This is done by means of linear approximations on uniform meshes. First, a careful Fourier analysis is constructed, highlighting the coexistence of two Fourier spectral branches or spectral diagrams (physical and spurious) related to the two components of the numerical solution (averages and jumps). Efficient filtering mechanisms are also developed by means of techniques previously proved to be appropriate for classical schemes like finite differences or P1-classical finite elements. In particular, the work presents a proof that the uniform observability property is recovered uniformly by considering initial data with null jumps and averages given by a bi-grid filtering algorithm. Finally, the book explains how these results can be extended to other more sophisticated conforming and non-conforming finite element methods, in particular to quad...
Self-assembling morphologies in a 1D model of two-inclusion-containing lipid membranes
Zhou, Ling; Cheng, Mingfei; Fang, Jinghuai; Peng, Ju
The self-assembling morphologies in a 1D model of two-inclusion-containing lipid membranes are investigated by using self-consistent field theory. It is found that the shape and overall volume fraction of lipids, the hydrophobic strength and the distance of inclusions play important roles in the morphology of lipid membrane. The membrane consisting of cylindrical lipids with a symmetrical head and tail only forms the well-known normal morphology. However, for the membrane consisting of cone-like lipids with a relatively big head, the increase of the hydrophobic strength of inclusions can realize the membrane transition from the normal morphology to the pore morphologies. With increasing distance between two inclusions, two pores, three pores and four pores appear in turn. Conversely, the increase of the overall volume fraction of lipids can make the membrane undergo a reentrant transition from pore morphologies to normal morphologies. The results may be helpful in our understanding of the pore-forming mechanism.
The optimization of high resolution topographic data for 1D hydrodynamic models
Ales, Ronovsky; Michal, Podhoranyi
The main focus of our research presented in this paper is to optimize and use high resolution topographical data (HRTD) for hydrological modelling. Optimization of HRTD is done by generating adaptive mesh by measuring distance of coarse mesh and the surface of the dataset and adapting the mesh from the perspective of keeping the geometry as close to initial resolution as possible. Technique described in this paper enables computation of very accurate 1-D hydrodynamic models. In the paper, we use HEC-RAS software as a solver. For comparison, we have chosen the amount of generated cells/grid elements (in whole discretization domain and selected cross sections) with respect to preservation of the accuracy of the computational domain. Generation of the mesh for hydrodynamic modelling is strongly reliant on domain size and domain resolution. Topographical dataset used in this paper was created using LiDAR method and it captures 5.9km long section of a catchment of the river Olše. We studied crucial changes in topography for generated mesh. Assessment was done by commonly used statistical and visualization methods.
Label-free optical detection of bacteria on a 1-D photonic crystal of porous silicon
Wu, Chia-Chen; Alvarez, Sara D.; Rang, Camilla U.; Chao, Lin; Sailor, Michael J.
The construction of a specific, label-free, bacteria biosensor using porous silicon 1-D photonic crystals will be described. Bacteria resident on the surface of porous silicon act as scattering centers for light resonant with the photonic crystal; the diffusely scattered light possesses the optical spectrum of the underlying photonic crystal. Using a spectrometer fitted to a light microscope, the bacteria are imaged without using exogenous dyes or labels and are quantified by measuring the intensity of scattered light. In order to selectively bind and identify bacteria using porous Si, we use surface modifications to reduce nonspecific binding to the surface and to engineer bacteria specificity onto the surface. Bovine serum albumin (BSA) was adsorbed to the porous Si surface to reduce nonspecific binding of bacteria. The coatings were then chemically activated to immobilize polyclonal antibodies specific to Escherichia coli. Two E. coli strains were used in our study, E. coli DH5α and non-pathogenic enterohemorrhagic Escherichia coli (EHEC) strain. The nonpathogenic Vibrio cholerae O1 strain was used to test for antibody specificity. Successful attachment of antibodies was measured using fluorescence microscopy and the scattering method was used to test for bacteria binding specificity.
Rapid Formation of 1D Titanate Nanotubes Using Alkaline Hydrothermal Treatment and Its Photocatalytic Performance
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Chin Wei Lai
Full Text Available One-dimensional (1D titanate nanotubes (TNT were successfully synthesized using alkaline hydrothermal treatment of commercial TiO2 nanopowders in a Teflon lined stainless steel autoclave at 150°C. The minimum time required for the formation of the titanate nanotubes was 9 h significantly. After the hydrothermal processing, the layered titanate was washed with acid and water in order to control the amount of Na+ ions remaining in the sample solutions. In this study, the effect of different reaction durations in a range of 3 h to 24 h on the formation of nanotubes was carried out. As the reaction duration is extended, the changes in structure from particle to tubular shapes of alkaline treated TiO2 were obtained via scanning electron microscope (SEM. Also, the significant impact on the phase transformation and crystal structure of TNT was characterized through XRD and Raman analysis. Indeed, the photocatalytic activity of TNT was investigated through the degradation of methyl orange aqueous solution under the ultraviolet light irradiation. As a result, TNT with reaction duration at 6 h has a better photocatalytic performance than other samples which was correlated to the higher crystallinity of the samples as shown in XRD patterns.
An enriched 1D finite element for the buckling analysis of sandwich beam-columns
Sad Saoud, Kahina; Le Grognec, Philippe
Sandwich constructions have been widely used during the last few decades in various practical applications, especially thanks to the attractive compromise between a lightweight and high mechanical properties. Nevertheless, despite the advances achieved to date, buckling still remains a major failure mode for sandwich materials which often fatally leads to collapse. Recently, one of the authors derived closed-form analytical solutions for the buckling analysis of sandwich beam-columns under compression or pure bending. These solutions are based on a specific hybrid formulation where the faces are represented by Euler-Bernoulli beams and the core layer is described as a 2D continuous medium. When considering more complex loadings or non-trivial boundary conditions, closed-form solutions are no more available and one must resort to numerical models. Instead of using a 2D computationally expensive model, the present paper aims at developing an original enriched beam finite element. It is based on the previous analytical formulation, insofar as the skin layers are modeled by Timoshenko beams whereas the displacement fields in the core layer are described by means of hyperbolic functions, in accordance with the modal displacement fields obtained analytically. By using this 1D finite element, linearized buckling analyses are performed for various loading cases, whose results are confronted to either analytical or numerical reference solutions, for validation purposes.
Monitoring heat-induced changes in soft tissues with 1D transient elastography
Energy Technology Data Exchange (ETDEWEB)
Benech, Nicolas; Negreira, Carlos A [Laboratorio de Acustica Ultrasonora, Facultad de Ciencias, Igua 4225, 11400, Montevideo (Uruguay)
In this paper 1D transient elastography was employed in fresh bovine skeletal muscle samples to assess the shear elastic modulus {mu} while the tissue was locally heated by means of an electrical resistance. The investigation is based on the study of the time shift of the shear wave propagation produced by the local temperature variation. The experiments show that the thermal expansion contribution to the time shift is negligible when compared with the shear wave speed variation. In such a case, the quantification of {mu} as a function of temperature becomes possible. Repeated experiments in different samples lead to a reproducible behavior of {mu} as a function of temperature. Irreversible elasticity changes are produced when the temperature exceeds a certain critical value T{sub c}. The proposed method allows estimating this value as well as the spatial extension of the resulting thermal lesion. This point is important when considering applications in monitoring focused ultrasound surgery (FUS) because the surrounding normal tissue should remain unaffected.
One-Loop Transition Amplitudes in the D1D5 CFT
Carson, Zaq; Mathur, Samir D
We consider the issue of thermalization in the D1D5 CFT. Thermalization is expected to correspond to the formation of a black hole in the dual gravity theory. We start from the orbifold point, where the theory is essentially free, and does not thermalize. In earlier work it was noted that there was no clear thermalization effect when the theory was deformed off the orbifold point to first order in the relevant twist perturbation. In this paper we consider the deformation to second order in the twist, where we do find effects that can cause thermalization of an initial perturbation. We consider a 1-loop process where two untwisted copies of the CFT are twisted to one copy and then again untwisted to two copies. We start with a single oscillator excitation on the initial CFT, and compute the effect of the two twists on this state. We find simple approximate expressions for the Bogoliubov coefficients and the behavior of the single oscillator excitation in the continuum limit, where the mode numbers involved are...