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Density functional study of gamma-aminopropyltriethoxysilane
NASA Astrophysics Data System (ADS)
Density functional theory calculations using Becke's three-parameter exchange functional in combination with the Lee-Young-Parr correlation functional (B3-LYP) and standard 6-311 + G(d,p) basis set were carried out to study the conformational stability and vibrational spectra of gamma-aminopropyltriethoxysilane. Calculations reveal the existence of two stable conformers trans and gauche. The calculated energy for the gauche conformation was found to be 608 cm-1 above the minimum energy of the trans conformation. Temperature dependence of Raman spectra of liquid APTES and DFT calculation enabled us to identify the vibrational bands characteristic for both conformers. It has been shown that there is an increase in the population of gauche conformer with increasing temperature.
Bistricic, L.; Volovsek, V.; Daani, V.; Leskovac, M.
Infrared analysis of the effect of composition of n-butyltriethoxysilane and gamma-aminopropyltriethoxysilane blends on tertiary amine-catalyzed anhydride-cured epoxy mixtures. Technical report
SciTech Connect
The enhancement in mechanical properties observed for silane-treated glass-reinforced epoxy materials is highly dependent on the structure of the coupling agent at the interphase. The effect of varying composition of nonhydrolyzed silane coupling agent blends of gamma aminopropyltriethoxysilane (APS) and butyltriethoxysilane (BTS) on the cure of benzyldimethylamine (BDMA)-catalyzed, nadic methyl anhydride (NMA)-cured diglycidyl ether of bisphenol-A epoxy (BDGE) was studied by Fourier transform infrared spectroscopy (FTIR). The silane blends perturbed the kinetics of the alternating anhydride-epoxy copolymerization reaction, with the perturbation being a nonlinear function of the relative amine concentration in the system.
Tidrick, S.L.; Ishida, H.; Koenig, J.L.
The Heparinization of Silicone Rubber Using Aminoorganosilane Coupling Agents.
National Technical Information Service (NTIS)
Further work concerning the heparinization of silicone rubber using gamma-aminopropyltriethoxysilane as a binding agent for the heparin moiety is described. Surfaces possessing greatly enhanced nonthrombogenic character were obtained. Aminopropyltriethoxy...
R. L. Merker L. J. Elyash S. H. Mayhew J. Y. C. Wang
Test of carcinogenicity in mouse skin: Methylenedianiline,. gamma. glycidyloxytrimethyloxysilane,. gamma. aminopropyltriethoxysilane and a mixture of m-phenylenediamine, methylenedianiline, and diglycidylether of bisphenol-A
Application of graded concentrations of four test substances in acetone to the skin of C3H mice five times a week resulted in the following: ..gamma..aminopropyltriethoxysilane at concentration of 100 and 50 wt/vol % was a severe and mild skin irritant in female C3Hf/Bd respectively and in males a mild skin irritant. Methylenedianiline at a concentration of 10 wt/vol % in methanol killed 4/9 females and 1/9 males. When acetone was the solvent 3/10 females and 3/10 males died within 2 weeks. No mortality or skin damage occurred with ..gamma..glycidyloxytrimethyloxysilane or the mixture of m-phenylenediamine, methylenedianiline and diglycidylether of bisphenol A (MDA). A study of the effects of a two-year, three times a week, topical application of the four test materials revealed no significant increase in skin tumors. The incidence of liver tumors appeared to be increased by exposure to methylenedianiline and with the mixture (MDA). Significant and dose-dependent increases in mortality were found in male mice with MDA and increased mortality at the highest dose (10.8 mg/week) in females. In the case of methylenedianiline excess mortality was found in both sexes. The precise cause of excess mortality from dermal absorption of the materials applied over a two-year period was not established. 5 refs., 12 figs., 12 tabs.
Holland, J.M.; Smith, L.H.; Frome, E.; Whitaker, M.J.; Gipson, L.C.; Fry, R.J.M.
Multifunctional nanoparticles as coupled contrast agents
PubMed Central
Engineering compact imaging probes with highly integrated modalities is a key focus in bionanotechnology and will have profound impact on molecular diagnostics, imaging, and therapeutics. However, combining multiple components on a nanometer scale to create new imaging modalities unavailable from individual components has proven challenging. Here, we demonstrate iron oxide and gold coupled core-shell nanoparticles with well defined structural characteristics (e.g., size, shell thickness, and core-shell separation) and physical properties (e.g., electronic, magnetic, optical, thermal, and acoustic). The resulting multifunctional nanoprobes not only offer contrast for electron microscopy, magnetic resonance imaging, and scattering-based imaging, but more importantly, enable a new imaging mode, magnetomotive photoacoustic (mmPA) imaging, with remarkable contrast enhancement compared to PA images using conventional nanoparticle contrast agents.
Jin, Yongdong; Jia, Congxian; Huang, Sheng-Wen; O'Donnell, Matthew; Gao, Xiaohu
Multifunctional nanoparticles as coupled contrast agents.
Engineering compact imaging probes with highly integrated modalities is a key focus in bionanotechnology and will have profound impact on molecular diagnostics, imaging and therapeutics. However, combining multiple components on a nanometre scale to create new imaging modalities unavailable from individual components has proven to be challenging. In this paper, we demonstrate iron oxide and gold-coupled core-shell nanoparticles (NPs) with well-defined structural characteristics (for example, size, shell thickness and core-shell separation) and physical properties (for example, electronic, magnetic, optical, thermal and acoustic). The resulting multifunctional nanoprobes not only offer contrast for electron microscopy, magnetic resonance imaging and scattering-based imaging but, more importantly, enable a new imaging mode, magnetomotive photoacoustic imaging, with remarkable contrast enhancement compared with photoacoustic images using conventional NP contrast agents. PMID:20975706
Potential of Titanate Coupling Agents in Solid Rocket Fuel Systems.
Titanate Coupling Agents are unique in that their reaction with the free protons at the inorganic interface results in the formation of hydrophobic-organophilic monomolecular layers on the inorganic surface creating novel surface energy modifications on p...
S. J. Monte G. Sugerman
Chemical modification of henequ�n fibers with an organosilane coupling agent
Microsoft Academic Search
Short henequ�n fibers were modified with a silane coupling agent in order to find out its deposition mechanism on the fiber surface and the influence of this chemical treatment on the mechanical properties of the composite. It was shown that the partial removal of lignin and other alkali soluble compounds from the fiber surface increases the adsorption of the silane
A Valadez-Gonzalez; R Olayo; P. J Herrera-Franco
Grafting of cellulose by fluorine-bearing silane coupling agents
The surface of model cellulose fibres, Avicell (AV), as well as that of Whatman paper (WP) was chemically modified with two fluorine-bearing alkoxysilane coupling agents, namely: 3,3,3-trifluoropropyl trimethoxysilane (TFPS) and 1H,1H,2H,2H,perfluorooctyl trimethoxysilane (PFOS). The occurrence of the grafting of soxhlet extracted modified cellulose was confirmed by the presence of silicon and fluorine atoms detected by elemental analysis, X-ray photoelectron spectroscopy
B. Ly; M. N. Belgacem; J. Bras; M. C. Brochier Salon
Coherent Pattern Prediction in Swarms of Delay-Coupled Agents
We consider a general swarm model of self-propelling agents interacting through a pairwise potential in the presence of noise and communication time delay. Previous work has shown that a communication time delay in the swarm induces a pattern bifurcation that depends on the size of the coupling amplitude. We extend these results by completely unfolding the bifurcation structure of the mean field approximation. Our analysis reveals a direct correspondence between the different dynamical behaviors found in different regions of the coupling-time delay plane with the different classes of simulated coherent swarm patterns. We derive the spatiotemporal scales of the swarm structures, as well as demonstrate how the complicated interplay of coupling strength, time delay, noise intensity, and choice of initial conditions can affect the swarm. In particular, our studies show that for sufficiently large values of the coupling strength and/or the time delay, there is a noise intensity threshold that forces a transition of the swarm from a misaligned state into an aligned state. We show that this alignment transition exhibits hysteresis when the noise intensity is taken to be time dependent.
Mier-y-Teran-Romero, Luis; Forgoston, Eric; Schwartz, Ira B.
Studies on the Effect of Coupling Agent on Glass Fiber Filled Polypropylene
Blends of polypropylene reinforced with glass fiber and chemical coupling agent were prepared by melt blending techniques. Maximum improvement in the mechanical and thermal properties was observed with one percent coupling agent, and these properties were further enhanced with increasing concentration of glass fiber, except impact strength and elongation at break, which decreased with an increased percentage of glass fiber.
A. P. Gupta; U. K. Saroop; G. S. Jha; Minakshi Verma
Effects of coupling agents on the mechanical properties improvement of the TiO 2 reinforced epoxy system
A study was carried out to investigate the effects of different coupling agents on the mechanical properties of the TiO2 particulate filled epoxy composite. Composites prepared by dispersing TiO2 coated with a silane coupling agent were compared with titanate coupling agent coated TiO2 dispersed composites. Young's modulus and flexural strength of titanate coupling agent treated composites were significantly improved compared
Manwar Hussain; Atsushi Nakahira; Shigehiro Nishijima; Koichi Niihara
Crosslinkable coupling agents: Synthesis and use for modification of interfaces in polymer blends
A novel coupling agent containing 2-oxazoline and 2-oxazinone as well as hydrosilane moieties has been prepared by hydrosilylation of the corresponding allyl ether containing precursor with a methylhydrosiloxane�dimethylsiloxane copolymer. This hydrosiloxane containing coupling agent, termed as SCA, was characterized by 1H NMR and its crosslinkability was proven by DSC. SCA was used for the modification of the interfaces in heterogeneous
J�rgen Pionteck; Veera Bhadraiah Sadhu; Lothar Jakisch; Petra P�tschke; Liane H�u?ler; Andreas Janke
Effects of coupling agent and filler dispersion on Vt characteristics of epoxy\\/silica nanocomposites
Epoxy\\/silica nanocomposites were investigated to clarify the effects of coupling agents and the degree of filler dispersion as for treeing breakdown V-t characteristics and PD (partial discharge) resistance performances. In the former case, it was clarified that homogeneous dispersion is critical to obtain satisfactory V-t characteristics, and that the addition of silane coupling agent would help improve such characteristics further.
T. Iizuka; Y. Ohki; T. Tanaka
Stable coexistence of an invasive plant and biocontrol agent: a parameterized coupled plant-herbivore model
Summary 1. Coupled plant-herbivore models, allowing feedback from plant to herbivore popu- lations and vice versa, enable us to predict the impact of biocontrol agents on their target weed populations; however, they are rarely used in biocontrol studies. We describe the population biology of the invasive plant Echium plantagineum and the weevil Mogulones larvatus , a biocontrol agent, in Australia.
Thermal-decomposition and crystallization behaviour of coupling agents for silver paste application
Coupling agents have been widely used to retard the sintering of silver paste and minimize co-firing defects due to densification mismatch between silver and dielectrics. The thermal-decomposition and crystallization behaviour of the coupling agent is a subject of great concern. Formation of the coupling agent layer is achieved by coating an Ag powder surface with Zr, Al or Ti organometallic compounds. Differential thermal analysis (DTA) detected an exothermic peak in Ag powder surfaces coated with Zr, Al or Ti which was absent in the uncoated silver powder. The exothermic peak clearly indicates the presence of the organic coupling agent on the Ag powder surface. The exothermic peak is absent when the sample is analysed in an N2 atmosphere, which suggests that the exothermic peak is related to oxidation of the coupling agent. To elucidate what is responsible for the oxidation, Ti organometallic compounds were calcined to different temperatures (350, 400, 500, 600 �C) for 2 h and the crystallization behaviour determined by x-ray diffraction (XRD). This demonstrated the presence of an anatase phase until a temperature of greater than 350 �C, and the intensity of the crystalline peak of (101) at 2theta = 25.3� increased continuously with the dwell time. Combining the results of DTA and XRD, it was found that formation of nanocrystallized titania accompanied the combustion of organometallic compounds.
Shih, Chi-Jen; Shih, Shao-Ju; Lin, Hong-Ching; Yeh, Hsin-Hsien; Hung, Ying-Chang
The effect of glass fiber and coupling agents in the blends of silicone rubber and liquid crystalline polymers
Blends of silicone rubber (VMQ) and liquid crystalline polymer (LCP) were prepared using a melt blending technique in the\\u000a presence and absence of glass fiber and coupling agents. The effect of glass fiber and coupling agents on the thermal, dynamic\\u000a mechanical, morphological pro-perties and cure characteristics of VMQ\\/LCP blends were studied. The vinyl silane coupling agent\\u000a showed a significant effect
T. Das; A. K. Banthia; B. Adhikari; Hyewon Jeong; Chang-Sik Ha; S. Alam
Development and Evaluation of Novel Coupling Agents for Kenaf-Fiber-Reinforced Unsaturated Polyester Composites
Natural fibers are gaining popularity as reinforcement materials for thermoset resins over the last two decades. Natural fibers are inexpensive, abundant, renewable and environmentally friendly. Kenaf fibers are one of the natural fibers that can potentially be used for reinforcing unsaturated polyester (UPE). As a polymer matrix, UPE enjoys a 40% market share of all the thermoset composites. This widespread application is due to many favorable characteristics including low cost, ease of cure at room temperature, ease of molding, a good balance of mechanical, electrical and chemical properties. One of the barriers for the full utilization of the kenaf fiber reinforced UPE composites, however, is the poor interfacial adhesion between the natural fibers and the UPE resins. The good interfacial adhesion between kenaf fibers and UPE matrix is essential for generating the desired properties of kenaf-UPE composites for most of the end applications. Use of a coupling agent is one of the most effective ways of improving the interfacial adhesion. In this study, six novel effective coupling agents were developed and investigated for kenaf-UPE composites: DIH-HEA, MFA, NMA, AESO-DIH, AESO-MDI, and AESO-PMDI. All the coupling agents were able to improve the interfacial adhesion between kanaf and UPE resins. The coupling agents were found to significantly enhance the flexural properties and water resistance of the kenaf-UPE composites. Fourier transform infrared spectroscopy (FTIR) confirmed all the coupling agents were covalently bonded onto kenaf fibers. Scanning electron microscopy (SEM) images of the composites revealed the improved interfacial adhesion between kanaf fibers and UPE resins.
Ren, Xiaofeng
Objective To identify predictors of promotion of couples� voluntary counseling and testing (CVCT) in Kigali, Rwanda Design Analysis of CVCT promotional agent (influential network leaders, INLs; influential network agents, INAs), and couple/invitation-level predictors of CVCT uptake. Methods Number of invitations and couples tested were evaluated by INL, INA, and couple/contextual factors. Multivariable logistic regression accounting for two-level clustering analyzed factors predictive of couples� testing. Results 26 INLs recruited and mentored 118 INAs who delivered 24,991 invitations. 4,513 couples sought CVCT services after invitation. INAs distributed an average of 212 invitations resulting in an average of 38 couples tested/agent. Characteristics predictive of CVCT in multivariate analyses included the invitee and INA being socially acquainted (aOR=1.4;95%CI:1.2�1.6); invitations delivered after public endorsement (aOR=1.3;95%CI:1.1�1.5); and presence of a mobile testing unit (aOR=1.4;95%CI:1.0�2.0). In stratified analyses, predictors significant among cohabiting couples included invitation delivery to the couple (aOR=1.2;95%CI:1.0�1.4) in the home (aOR=1.3;95%CI:1.1�1.4), while among non-cohabiting couples predictors included invitations given by unemployed INAs (aOR=1.7;95%CI:1.1�2.7). Cohabiting couples with older men were more likely to test, while younger age was associated with testing among men in non-cohabiting unions. Conclusions Invitations distributed by influential people were successful in prompting couples to seek joint HIV testing, particularly if the invitation was given in the home to someone known to the INA, and accompanied by a public endorsement of CVCT. Mobile units also increased the number of couples tested. Country-specific strategies to promote CVCT programs are needed to reduce HIV transmission among those at highest risk for HIV in sub-Saharan Africa.
Wall, Kristin; Karita, Etienne; Nizam, Azhar; Bekan, Brigitte; Sardar, Gurkiran; Casanova, Debbie; Joseph, Dvora; De Clercq, Freya; Kestelyn, Evelyne; Bayingana, Roger; Tichacek, Amanda; Allen, Susan
The effects of a silane coupling agent on curing characteristics and mechanical properties of bamboo fibre filled natural rubber composites
The effects of a silane coupling agent on curing characteristics and mechanical properties of bamboo fibre filled natural rubber composites were studied. Scorch time, t2 and cure time, t90 of the composites decrease with increasing filler loading and with the presence of a silane coupling agent, Si69. Mooney viscosity also increases with increasing filler loading but at a similar filler
Hanafi Ismail; S Shuhelmy; M. R Edyham
Coupling multi-agent model and GIS to simulate pine wood nematode disease spread in ZheJiang Province, China
A coupled method based on multi-agent model, remote sensing and GIS is described to simulate the forest disease spread. The coupled model focuses on the temporal dynamics of the Bursaphelenchus xylophilus population at the landscape scale. Each individual is modeled as an autonomous agent who behaves according to a set of rules including spreading in the landscape, feeding on Pinus
Huaguo Huang; Lei Wang; XiaoLi Zhang; YouQing Luo; Liqiong Zhao
Effect of silane coupling agents on the mooney scorch time of silica-filled natural rubber compound
Mooney scorch time and cure index of silica-filled natural rubber (Hevea Brasiliensis type) compound with and without the presence of silane coupling agents were studied in the temperature range 110�160�C using a Mooney Shearing Disk Viscometer. Two types of silane coupling agents, viz ?-mercaptopropyltrimethoxysilane (A-189) and bis(triethoxysilylpropyl)tetrasulphide (Si-69) of various loadings were used to study the effect of silane coupling
B. T. Poh; C. C. Ng
Surface organic modification of Fe 3O 4 nanoparticles by silane-coupling agents
Fe3O4 nanoparticles were prepared by chemistry co-precipitation and the mean crystal size was 17.9 nm measured by XRD. After it had been treated by silane-coupling agents KH570, magnetic microspheres dispersed in organic medium glycol were gained and the mean size of Fe3O4 nanopowders was 33.7 nm. So it can be concluded that magnetic micro-sphere is made of a few Fe3O4
Sheng GUI; Xiaodong SHEN; Benlan LIN
Triazole-forming waterborne polyurethane composites fabricated with silane coupling agent functionalized nano-silica.
In the research work, "click" chemistry was used to modify waterborne polyurethane (WPU) with silane coupling agent (SiCA) functionalized nano-silica. The modified WPU (CWPU) was characterized by FTIR, scanning electron microscope (SEM), thermogravimetric analysis (TGA) and contact angle measurement. The experiment results show that the modification can improve the thermal stability, hardness, and water or weather resistance of CWPU. PMID:21669435
Sun, Daoxing; Miao, Xiao; Zhang, Kejie; Kim, Hern; Yuan, Yongan
Mechanistic aspects of the role of coupling agents in silica�rubber composites
Compared to carbon black, the use of silica as reinforcing filler for rubber results in lower hysteretic losses, for tyre applications leading to lower rolling resistance and consequently fuel savings. The compatibility of hydrophilic silica with a hydrophobic rubber polymer matrix is generally poor. Adding bi-functional coupling agents to the compounds, commonly bis(triethoxysilylpropyl) tetrasulphide (TESPT), enhances filler-matrix compatibility. The degree
J. W. ten Brinke; S. C. Debnath; L. A. E. M. Reuvekamp; J. W. M. Noordermeer
Agent-based Model for the Coupled Human-Climate System
Integrated assessment models have been used to predict the outcome of coupled economic growth, resource use, greenhouse gas emissions and climate change, both for scientific and policy purposes. These models generally have employed significant simplifications that suppress nonlinearities and the possibility of multiple equilibria in both their economic (DeCanio, 2005) and climate (Schneider and Kuntz-Duriseti, 2002) components. As one step toward exploring general features of the nonlinear dynamics of the coupled system, we have developed a series of variations on the well studied RICE and DICE models, which employ different forms of agent-based market dynamics and "climate surprises." Markets are introduced through the replacement of the production function of the DICE/RICE models with an agent-based market modeling the interactions of producers, policymakers, and consumer agents. Technological change and population growth are treated endogenously. Climate surprises are representations of positive (for example, ice sheet collapse) or negative (for example, increased aerosols from desertification) feedbacks that are turned on with probability depending on warming. Initial results point toward the possibility of large amplitude instabilities in the coupled human-climate system owing to the mismatch between short outlook market dynamics and long term climate responses. Implications for predictability of future climate will be discussed. Supported by the Andrew W Mellon Foundation and the UC Academic Senate.
Zvoleff, A.; Werner, B.
Surface modification of Fe3O4@SiO2 microsphere by silane coupling agent
In the present study, Fe3O4@SiO2 core-shell microspheres were prepared via two steps. First, Fe3O4 nanoparticles were synthesized by co-precipitation of Fe+3 and Fe+2 as reaction substrates and NaOH as precipitant. Second, the surface of Fe3O4 was coated with silica by hydrolysis of tetraethylorthosilicate as the silica source. Subsequently, in order to reduce the amount of interaction and the agglomeration of Fe3O4@SiO2 microspheres, the silica shell of these particles was modified by vinyltriethoxysilane as the silane coupling agent. The structural properties of the samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and Fourier transform infrared spectroscopy analyses. The results indicated that the average sizes of Fe3O4 and Fe3O4@SiO2 particles were about 50 and 500 nm, respectively. Also, the surface characterization of Fe3O4@SiO2 microspheres showed that the silane coupling agent was covalently coupled with the silica surface.
Ahangaran, Fatemeh; Hassanzadeh, Ali; Nouri, Sirous
The Effect of Ethylene Diamine Dilaurate and Silane Coupling Agent on Cure Characteristics, Mechanical, and Thermal Properties of Silica-Filled Natural Rubber Composites
The influence of a new coupling agent, ethylene diamine dilaurate (EDD) and a commercial silane coupling agent, (Si-69) on the cure characteristics, mechanical and morphological properties of silica-filled natural rubber (NR) composites was studied. The results show that scorch time and cure time decreased with an increase in both coupling agents' content, but maximum and minimum torques exhibit the opposite
H. Ismail; Suryadiansyah; B. Azhari
The effects of partial replacement of oil palm wood flour by silica and silane coupling agent on properties of natural rubber compounds
The effects of partial replacement of oil palm wood flour (OPWF) by silica and silane coupling agent on mechanical properties and curing characteristics of natural rubber compounds were investigated. Compared to the control compound (50 phr of OPWF and without coupling agent), increasing the silica in the weight ratio of OPWF\\/silica and adding silane coupling agent increases the scorch time,
Hanafi Ismail; H. P. S Abdul Khalil
End-functional silicone coupling agent modified PEO\\/P(VDF-HFP)\\/SiO2 nanocomposite polymer electrolyte DSSC
The end-functional silicone coupling agent (dodecyl-trimethoxysilane, DTMS for short) was used to modify the PEO\\/P(VDF-HFP)\\/SiO2 nanocomposite polymer electrolyte (CPE) and the different amounts of DTMS modification effects were studied. The experiments showed the silicone coupling agent with hydrophobic alkyl chains (-C12H25) chemically engineered on the SiO2 nanoparticles, and formed a Si-O-Si cross-linked network in the new nanocomposite polymer electrolyte. Proper
Jing Zhang; Ying Yang; Sujuan Wu; Sheng Xu; Conghua Zhou; Hao Hu; Bolei Chen; Xiaodong Xiong; Bobby Sebo; Hongwei Han; Xingzhong Zhao
Effects of coupling agents on structure and properties of polyimide\\/Al2O3 nanocomposite films
Purpose � The purpose of this paper is to investigate the effects of coupling agents on the structure and properties of the nanocomposite films and clarify their mechanism. Polyimide (PI)\\/Al2O3 nanocomposite films were prepared using different coupling agents. Design\\/methodology\\/approach � Poly(amic acid) (PAA) was firstly synthesised from appropriate pyromellitic diannanocomposite and oxydianiline in N-dimethylacetamide. Calculated amount of nano-Al2O3 particles modified
L. Z. Liu; L. Weng; Y. X. Song; L. Gao; H. Zhao; Q. Q. Lei
Study on the process of surface modification of dehydrated palygorskite based on XD-172 silane coupling agent
Three types of dehydrated palygorskites are prepared, and XD-172 silane coupling agents are used to modify dehydrated palygorskite by the drop height method employed to evaluate the effects of surface modification. The optimal modification process parameters are obtained by analyzing the influences of modification agents quality, modification temperature and modification time on drop height, so that it could provide the
Fei Du; Lin He
ZnO nanowire-based glucose biosensors with different coupling agents
ZnO-nanowire-based glucose biosensors were fabricated by immobilizing glucose oxidase (GOx) onto a linker attached to ZnO nanowires. Different coupling agents were used, namely (3-aminopropyl)trimethoxysilane (APTMS), (3-aminopropyl)triethoxysilane (APTES), and (3-aminopropyl)methyldiethoxysilane (APS), to increase the affinity of GOx binding to ZnO nanowires. The amount of GOx immobilized on the ZnO nanowires, the performance, sensitivity, and Michaelis-Menten constant of each biosensor, and the electron transfer resistance through the biosensor were all measured in order to investigate the effect of the coupling agent on the ZnO nanowire-based biosensor. Among the different biosensors, the APS-treated biosensor had the highest sensitivity (17.72 ?A cm-2 mM-1) and the lowest Michaelis-Menten constant (1.37 mM). Since APS-treated ZnO nanowires showed the largest number of Csbnd N groups and the lowest electron transfer resistance through the biosensor, we concluded that these properties were the key factors in the performance of APS-treated glucose biosensors.
Jung, Juneui; Lim, Sangwoo
Cytocompatibility and Mechanical Properties of Short Phosphate Glass Fibre Reinforced Polylactic Acid (PLA) Composites: Effect of Coupling Agent Mediated Interface
In this study three chemical agents Amino-propyl-triethoxy-silane (APS), sorbitol ended PLA oligomer (SPLA) and Hexamethylene diisocyanate (HDI) were identified to be used as coupling agents to react with the phosphate glass fibre (PGF) reinforcement and the polylactic acid (PLA) polymer matrix of the composite. Composites were prepared with short chopped strand fibres (l = 20 mm, ? = 20 �m) in a random arrangement within PLA matrix. Improved, initial composite flexural strength (~20 MPa) was observed for APS treated fibres, which was suggested to be due to enhanced bonding between the fibres and polymer matrix. Both APS and HDI treated fibres were suggested to be covalently linked with the PLA matrix. The hydrophobicity induced by these coupling agents (HDI, APS) helped to resist hydrolysis of the interface and thus retained their mechanical properties for an extended period of time as compared to non-treated control. Approximately 70% of initial strength and 65% of initial modulus was retained by HDI treated fibre composites in contrast to the control, where only ~50% of strength and modulus was retained after 28 days of immersion in PBS at 37 �C. All coupling agent treated and control composites demonstrated good cytocompatibility which was comparable to the tissue culture polystyrene (TCP) control, supporting the use of these materials as coupling agent�s within medical implant devices.
Hasan, Muhammad Sami; Ahmed, Ifty; Parsons, Andrew; Walker, Gavin; Scotchford, Colin
The Compatibility Effect Of Coupling Agent On Rheological-Morphological Relationship Of Banana Fibre Reinforced Polypropylene
The rheological properties of banana fibre reinforced polypropylene (PP/BF) composites at different composition were analysed using Shimadzu capillary rheometer. The effect of coupling agent concentration on the rheological properties was studied and followed by drawing a relationship of rheological-morphological properties of PP/BF composites. It was found that all composite system exhibits pseudoplasticity and incorporation of treated fibres consequents enhanced viscosity due to improved interfacial adhesion at fibre-matrix interface. However, it was observed that PP/BF composite with 2 wt% silane concentration does not yield further enhancement in the rheological properties when compared to that of 1 wt%. Composites with 1 wt% silane concentration were found to yield most promising compatibility effect with well-oriented and uniformly dispersed fibre morphology.
Chang, S. Y.; Shamsudin, Z. [Department of Engineering Materials, Faculty of Manufacturing Engineering, Universiti Teknikal Malaysia Melaka, 75450 Ayer Keroh, Melaka (Malaysia)
The effects of corn zein protein coupling agent on mechanical properties of flax fiber reinforced composites
In the field of renewable materials, natural fiber composites demonstrate the capacity to be a viable structural material. When normalized by density, flax fiber mechanical properties are competitive with E-glass fibers. However, the hydrophilic nature of flax fibers reduces the interfacial bond strength with polymer thermosets, limiting composite mechanical properties. Corn zein protein was selected as a natural bio-based coupling agent because of its combination of hydrophobic and hydrophilic properties. Zein was deposited on the surface of flax, which was then processed into unidirectional composite. The mechanical properties of zein treated samples where measured and compared against commonly utilized synthetic treatments sodium hydroxide and silane which incorporate harsh chemicals. Fourier transform infrared spectroscopy, chemical analysis, and scanning electron microscopy were also used to determine analyze zein treatments. Results demonstrate the environmentally friendly zein treatment successfully increased tensile strength 8%, flexural strength 17%, and shear strength 30% compared to untreated samples.
Whitacre, Ryan John
Improved mechanical properties of HDPE/nano-alumina composite through silane coupling agent
The effect of silane coupling agent to mechanical properties of HDPE/nano-alumina composite was investigated. Nano-alumina used in this study was produced by using sol-gel method. The shape and size of nano-alumina were determined by using TEM. Prior to the usage of nano alumina as a filler in the polymer matrix, (3-methacryloxypropyl) trimethoxysilane (MPS) was used to functionalize the nanoparticles due to its bifunctional nature: hydrolysable group (-Si(OCH3)3) and unsaturated carbon-carbon double bond. The XRD result shows diffraction spectrum of the synthesized nano-alumina. In order to improve the mechanical properties of the composite, nanoalumina was treated with (3-methacryloxypropyl) trimethoxysilane (MPS). A high tensile strength, is achieved at 4 wt% of MPS.
Akmil, N.; Luqman, C. A.; Ahmad, M.; Zaman, K.
Investigation of oil recovery improvement by coupling an interfacial tension agent and a mobility control agent in light oil reservoirs. Annual report, October 1992--September 1993
Investigation of Oil Recovery Improvement by Coupling and Interfacial Tension Agent and a Mobility Control Agent in Light Oil Reservoirs will study two major areas concerning co-injecting an interfacial tension reduction agent(s) and a mobility control agent. The first area defines the interactions of alkaline agent, surfactants, and polymers on a fluid-fluid and fluid-rock basis. The second area concerns the economic improvement of the combined technology. This report examines the interactions of different alkaline agents, surfactants, and polymer combinations on a fluid-fluid basis. Alkali and surfactant combine to reduce the interfacial tension between a low acid number, 42 API gravity crude oil and the aqueous solution to values lower than either agent alone. Surfactant structure can vary from linear chain sulfonates to alkyl aryl sulfonates to produce low interfacial tension values when combined with alkali. However as a class, the alkyl aryl sulfonates were the most effective surfactants. Surfactant olefinic character appears to be critical in developing low interfacial tensions. For the 42 API gravity crude oil, surfactants with molecular weights ranging from 370 to 450 amu are more effective in lowering interfacial tension. Ultra low interfacial tensions were achieved with all of the alkaline agents evaluated when combined with appropriate surfactants. Different interfacial tension reduction characteristics with the various alkali types indicates alkali interacts synergistically with the surfactants to develop interfacial tension reduction. The solution pH is not a determining factor in lowering interfacial tension. Surfactant is the dominant agent for interfacial tension reduction.
Pitts, M.J.
Effects of the methyltrimethoxysilane coupling agent on phenolic and miscanthus composites containing calcium sulfite scrubber material
The purpose of this research is to test the effects of methyltrimethoxysilane coupling agent on composite material containing calcium sulfite obtained from the Southern Illinois Power Co-operative. This scrubber material and the miscanthus plant are of interest due to their use in coal burning power plants to reduce toxic emission. When calcium sulfate is passed through coal fire gas emissions it absorbs mercury and sulfur. In these composites it is used as filler to reduce cost. Miscanthus is a source of both cellulose reinforcement and some natural resin. This plant has low care requirements, little mineral content, useful energy return, and positive environmental effects. Under investigation is whether a post-cure procedure or a silane coupling agent will positively impact the composite. Hot pressing alone may not be enough to fully cure the phenolic. It is hoped that the silane will increase the strength characteristics of the composite by enhancing adhesion between the calcium sulfite and phenolic resin. Possible effects on the miscanthus by the silane will also be tested. Phenolic is being utilized because of its recycling and biodegradable properties along with cost effectiveness in mass production. Composite mechanical performance was measured through 3-point bending to measure flexural strength and strain at breakage. A dynamic mechanical analyzer (DMA) was used to find thermomechanical properties. The post-cure was found to be effective, particularly on the final composite containing silane. When methyltrimethoxysilane was added to the miscanthus prior to fabrication, it was found to reduce flexural strength and density. However the addition of methyltrimethoxysilane to the calcium sulfite altered thermo-mechanical properties to a state more like pure phenolic, with added flexibility and thermal stability.
Jones, Sean
Effect of fibre and coupling agent contents on water absorption and flexural modulus of wood fibre polyethylene composites
In two previous studies, wood fiber-reinforced polymer composites (WPC) were prepared via melt processing. In particular, a response surface strategy of a 20 run optimal design for these three factors was adopted. It was found that for these WPC mixing torque, melt viscosity, Young's modulus and tensile stress at break were related to the type of wood used, as well as wood and coupling agent contents. In addition, thermal properties and strain at break were mainly affected by wood and coupling agent contents. Here, a more complete characterization of these WPC under extreme environmental conditions is performed. In particular, the effect of coupling agent content, wood fibre content and wood fibre type on water absorption and flexural modulus are reported under different water immersion time and temperature. The results show that water absorption is influenced by all the parameters studied, while flexural modulus is mainly influenced by wood content and immersion temperature.
Tissandier, C.; Zhang, Y.; Rodrigue, D.
Influence of silane coupling agent on the conversion film forming of galvanized steel treated with cerium salt
The influence of silane coupling agent on the film forming of galvanized steel treated with cerium salt was studied by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS), and the corrosion resistance of conversion films was analyzed by electro interstitial scanning (EIS). The results show that silane coupling agent KH-570 has significant influence on the compactness and homogeneity of cerium conversion films, and the process of film forming is promoted by increasing the content of tervalent and tetravalent cerium oxide. The impedance value of the cerium conversion film, especially modified with KH-570, is greater than that of the base metal, which reveals that it is necessary to add silane coupling agent to the film-forming solution in order to improve the corrosion resistance of the conversion film.
Gong, Li-hua; Tang, Rui-rui; Zhu, Yu-qiao; Chen, Dong-liang
Detection of chemical warfare agent degradation products in foods using liquid chromatography coupled to inductively coupled plasma mass spectrometry and electrospray ionization mass spectrometry
The following work presents the exploration of three chromatographic separations in combination with inductively coupled plasma mass spectrometry (ICP-MS) for the analysis of chemical warfare agent degradation products (CWADPs). The robust ionization of ICP is virtually matrix independent thus enabling the examination of sample matrices generally considered too complicated for analysis by electrospray ionization (ESI) or atmospheric pressure chemical ionization
Kevin M. Kubachka; Douglas D. Richardson; Douglas T. Heitkemper; Joseph A. Caruso
Cytocompatibility and Mechanical Properties of Short Phosphate Glass Fibre Reinforced Polylactic Acid (PLA) Composites: Effect of Coupling Agent Mediated Interface.
In this study three chemical agents Amino-propyl-triethoxy-silane (APS), sorbitol ended PLA oligomer (SPLA) and Hexamethylene diisocyanate (HDI) were identified to be used as coupling agents to react with the phosphate glass fibre (PGF) reinforcement and the polylactic acid (PLA) polymer matrix of the composite. Composites were prepared with short chopped strand fibres (l = 20 mm, ? = 20 �m) in a random arrangement within PLA matrix. Improved, initial composite flexural strength (~20 MPa) was observed for APS treated fibres, which was suggested to be due to enhanced bonding between the fibres and polymer matrix. Both APS and HDI treated fibres were suggested to be covalently linked with the PLA matrix. The hydrophobicity induced by these coupling agents (HDI, APS) helped to resist hydrolysis of the interface and thus retained their mechanical properties for an extended period of time as compared to non-treated control. Approximately 70% of initial strength and 65% of initial modulus was retained by HDI treated fibre composites in contrast to the control, where only ~50% of strength and modulus was retained after 28 days of immersion in PBS at 37 �C. All coupling agent treated and control composites demonstrated good cytocompatibility which was comparable to the tissue culture polystyrene (TCP) control, supporting the use of these materials as coupling agent's within medical implant devices. PMID:24955744
Surface modification of TiO2 nanoparticles via photocataliticaly induced reaction: Influence of functionality of silane coupling agent
In the present work the surface modification of TiO2 nanoparticles by photocatalyticaly induced reaction with silane coupling agent 3-triethoxysilyl propyl isocianate (PIC) has been presented. It was demonstrated establishing of covalent Tisbnd Osbnd Si bond between the nanoparticles and the PIC molecule. In comparison with previous results, it was demonstrated the high influence of the functional group from the silane coupling agent on the reaction course during surface functionalziation of TiO2 nanoparticles. Depending on the amount and type (electronegativity of the end-functionalities) of the silane compound, high control of the surface characteristics of TiO2 nanoparticles could be achieved.
Tomovska, Radmila; Daniloska, Vesna; Asua, Jose M.
The effect of interstitial pressure on therapeutic agent transport: Coupling with the tumor blood and lymphatic vascular systems.
Vascularized tumor growth is characterized by both abnormal interstitial fluid flow and the associated interstitial fluid pressure (IFP). Here, we study the effect that these conditions have on the transport of therapeutic agents during chemotherapy. We apply our recently developed vascular tumor growth model which couples a continuous growth component with a discrete angiogenesis model to show that hypertensive IFP is a physical barrier that may hinder vascular extravasation of agents through transvascular fluid flux convection, which drives the agents away from the tumor. This result is consistent with previous work using simpler models without blood flow or lymphatic drainage. We consider the vascular/interstitial/lymphatic fluid dynamics to show that tumors with larger lymphatic resistance increase the agent concentration more rapidly while also experiencing faster washout. In contrast, tumors with smaller lymphatic resistance accumulate less agents but are able to retain them for a longer time. The agent availability (area-under-the curve, or AUC) increases for less permeable agents as lymphatic resistance increases, and correspondingly decreases for more permeable agents. We also investigate the effect of vascular pathologies on agent transport. We show that elevated vascular hydraulic conductivity contributes to the highest AUC when the agent is less permeable, but to lower AUC when the agent is more permeable. We find that elevated interstitial hydraulic conductivity contributes to low AUC in general regardless of the transvascular agent transport capability. We also couple the agent transport with the tumor dynamics to simulate chemotherapy with the same vascularized tumor under different vascular pathologies. We show that tumors with an elevated interstitial hydraulic conductivity alone require the strongest dosage to shrink. We further show that tumors with elevated vascular hydraulic conductivity are more hypoxic during therapy and that the response slows down as the tumor shrinks due to the heterogeneity and low concentration of agents in the tumor interior compared with the cases where other pathological effects may combine to flatten the IFP and thus reduce the heterogeneity. We conclude that dual normalizations of the micronevironment - both the vasculature and the interstitium - are needed to maximize the effects of chemotherapy, while normalization of only one of these may be insufficient to overcome the physical resistance and may thus lead to sub-optimal outcomes. PMID:24751927
Wu, Min; Frieboes, Hermann B; Chaplain, Mark A J; McDougall, Steven R; Cristini, Vittorio; Lowengrub, John S
Preparation of a Conducting Flexible Material from Silane Coupling Agent and Hydroxyl Terminated Polybutadiene Rubber by Hydrolysis and Condensation
Synthesis and characterization of a flexible polymer produced from silane coupling agent (SCA) and hydroxyl terminated polybutadiene (HTPB) were performed. Mechanical properties of chemically and electrochemically prepared conducting composites synthesized from this polymer were investigated. Conductivities of the composites were also measured. Polypyrrole enhanced the mechanical properties of the chemically prepared conducting composite. Doping with iodine greatly changed the conductivity
Yunus Karatas; Levent Toppare; Teoman Tin�er
Effect of silane coupling agents on the wear resistance of polymer-nanoporous silica gel dental composites
Particle pre-treatment with a silane coupling agent, ?-methacryloxypropyltrimethoxysilane, increased the wear rate of triethylglycoldimethacrylate (TEGDMA) composites reinforced with HF-catalyzed nanoporous silica gel. The percentage filler porosity appeared to exert the greatest control on the wear properties. Increasing silanation led to a decrease in the surface area and total pore volume, resulting in a linear increase in the wear rate. It
Jiazhong Luo; Robert Seghi; John Lannutti
Bifunctional Coupling Agents for Radiolabeling of Biomolecules and Target-Specific Delivery of Metallic Radionuclides
Receptor-based radiopharmaceuticals are of great current interest in early molecular imaging and radiotherapy of cancers, and provide a unique tool for target-specific delivery of radionuclides to the diseased tissues. In general, a target-specific radiopharmaceutical can be divided into four parts: targeting biomolecule (BM), pharmacokinetic modifying (PKM) linker, bifunctional coupling or chelating agent (BFC), and radionuclide. The targeting biomolecule serves as a �carrier� for specific delivery of the radionuclide. PKM linkers are used to modify radiotracer excretion kinetics. BFC is needed for radiolabeling of biomolecules with a metallic radionuclide. Different radiometals have significant difference in their coordination chemistry, and require BFCs with different donor atoms and chelator frameworks. Since the radiometal chelate can have a significant impact on physical and biological properties of the target-specific radiopharmaceutical, its excretion kinetics can be altered by modifying the coordination environment with various chelators or coligand, if needed. This review will focus on the design of BFCs and their coordination chemistry with technetium, copper, gallium, indium, yttrium and lanthanide radiometals.
Liu, Shuang
Using silane coupling agents to prepare raspberry-shaped polyaniline hollow microspheres with tunable nanoshell thickness.
In this paper, we present the facile preparation of polyaniline (PANI) hollow spheres by using a silane coupling agent, N-[3-(trimethoxysilyl) propyl]aniline (PAPTMS), as a precursor. The PANI hollow spheres exhibit tunable shell thickness. PAPTMS was used to prepare aniline-modified silica microparticles, ~550 nm in diameter, by the St�ber process. PANI-coated silica core-shell microcapsules (SiO(2)@PANI) were subsequently obtained by performing chemically oxidative polymerization of a specific aniline monomer loading in the presence of the core-shell particles. PANI hollow spheres with tunable PANI shell thicknesses were eventually obtained by immersing the as-prepared core-shell particles in 5 wt% HF aqueous solutions to simultaneously remove the silica cores and further dope the PANI shells. The as-prepared core-shell particles and PANI hollow spheres were characterized using Fourier-transform infrared (FTIR) and (29)Si nuclear magnetic resonance (NMR) spectroscopies. The surface morphologies of the core-shell particles and PANI hollow spheres were investigated using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The electrical conductivities and optical absorption spectra of the as-prepared core-shell microparticles and the PANI hollow spheres were measured using the standard four-point probe method and ultraviolet-visual (UV-Vis) absorption spectroscopy, respectively. PMID:23261336
Dai, Chung-Feng; Weng, Cheng-Jian; Chien, Chao-Ming; Chen, Ya-Lun; Yang, Shan-Yuan; Yeh, Jui-Ming
Socio-Ecohydrologic Agents And Services: Integrating Human And Natural Components To Address Coupled System Resilience
Riparian corridors in arid regions are highly valued for their relative scarcity, and because healthy riparian systems support high levels of biodiversity, can meet human demand for water and water-related resources and functions. Our team is taking a transdiciplinary social-ecological systems approach to assessing riparian corridor resilience in two watersheds (the San Pedro River in USA and Mexico, and the Rio San Miguel in Mexico) through a project funded by the NSF CNH program ("Strengthening Resilience of Arid Region Riparian Corridors"). Multiple perspectives are integrated in the project, including hydrology, ecology, institutional dynamics, and decision making (at the level of both policy and individual choice), as well as the perspectives of various stakeholder groups and individuals in the watersheds. Here we discuss initial findings that center around linking changes in ecohydrology and livelihoods related to decisions in response to climatic, ecological, and social change. The research team is implementing two approaches to integrate the disparate disciplines participating in the research (and the varied perspectives among the stakeholders in this binational riparian context): (1) ecosystem service assessment, and (2) agent based model simulation. We are developing an ecosystem service perspective that provides a bridge between ecological dynamics in the landscape and varied stakeholder perspectives on the implications of ecohydrology for well-being (economic, cultural, ecological). Services are linked on one hand to the spatial patterns of traits of individuals within species (allowing a more predictive application of ecosystem services as they vary with community change in time), and to stakeholder perspectives (facilitating integration of ecosystem services into our understanding of decision making processes) in a case study in the San Pedro River National Conservation Area. The agent- based model (ABM) approach incorporates the influence of human decision-making on spatially-explicit landscapes in a mechanistic way, taking into account social interaction, adaptation, and decision-making at different levels, allowing individual stakeholders to make decisions based on their unique perceptions of their environment, be it economic, social, or ecological awareness. Initial parameterization of the ABM proceeds from a case study centered in the town of Ray�n, Sonora, Mexico, where semi-structured interviews were used to elicit perceptions by water resource users of CNH function, change, and solutions relating to livelihood changes in response to several drivers. In both case studies, we see the potential and limitations for an approach to adaptive management and decision support related to water resources that links ecosystem services and agent-based modeling. Methodologically, synthetic approaches such as these may allow coupling of systems for improved assessment and analysis, while at the same time lack a connection to the perspectives of water users and managers on the ground. There is thus potential for a either a loss of system resilience in the face of external change, or an opportunity to increase system resilience by building off perspectives already in place within these coupled socio-ecohydrologic systems.
Pavao-zuckerman, M.; Pope, A.; Chan, D.; Curl, K.; Gimblett, H. R.; Hough, M.; House-Peters, L.; Lee, R.; Scott, C. A.
Tantalum pentachloride as a coupling agent for stereohindered amide bond formation
We have previously reported that tantalum carboxylates show high reactivity toward primary amines to give primary amides. We report herein that tantalum pentachloride, in contrast with the behavior of standard coupling reagents, mediates the couplings of secondary amines and the couplings of very hindered carboxylates. Such coupling reactions are particularly difficult to achieve, when using chiral carboxylates (including N-protected amino
Jiang Bao Fang; Rashmi Sanghi; Joachim Kohn; Alan S. Goldman
Investigation of oil recovery improvement by coupling an interfacial tension agent and a mobility control agent in light oil reservoirs. Second annual report, October 1993--September 1994
{open_quotes}Investigation of Oil Recovery Improvement by Coupling an Interfacial Tension Agent and a Mobility Control Agent in Light Oil Reservoirs{close_quotes} is studying two major areas concerning co-injecting an interfacial tension reduction agent(s) and a mobility control agent. The first area defines the interactions of alkaline agents, surfactants, and polymers on a fluid-fluid and a fluid-rock basis. The second area concerns the economic improvement of the combined technology. This report continues the fluid-fluid interaction evaluations and begins the fluid-rock studies. Fluid-fluid interfacial tension work determined that replacing sodium ion with either potassium or ammonium ion in solutions with interfacial tension reduction up to 19,600 fold was detrimental and had little or no effect on alkali-surfactant solutions with interfacial tension reduction of 100 to 200 fold. Reservoir brine increases interfacial tension between crude oil and alkaline-surfactant solutions. Na{sub 2}CO{sub 3}-surfactant solutions maintained ultra low and low interfacial tension values better than NaOH-surfactant solutions. The initial phase of the fluid-rock investigations was adsorption studies. Surfactant adsorption is reduced when co-dissolved with alkali. Na{sub 2}CO{sub 3} and Na{sub 3}PO{sub 4} are more efficient at reducing surfactant adsorption than NaOH. When polymer is added to the surfactant solution, surfactant adsorption is reduced as well. When both polymer and alkali are added, polymer is the dominate component, reducing the Na{sub 2}CO{sub 3} and NaOH effect on adsorption. Substituting sodium ion with potassium or ammonium ion increased or decreased surfactant adsorption depending on surfactant structure with alkali having a less significant effect. No consistent change of surfactant adsorption with increasing salinity was observed in the presence or absence of alkali or polymer.
Highly Efficient Arsenic Removal Using a Composite of Ultrafine Magnetite Nanoparticles Interlinked by Silane Coupling Agents
Arsenic (As) contamination in groundwater is a great environmental health concern and is often the result of contact between groundwater and arsenic-containing rocks or sediments and from variation of pH and redox potentials in the subsurface. In the past decade, magnetite nanoparticles (MNPs) have been shown to have high adsorption activity towards As. Alerted by the reported cytotoxicity of 5�12 nm MNP, we studied the adsorption behavior of 1.15 nm MNP and a MNP composite (MNPC), MNPs interlinked by silane coupling agents. With an initial concentration of As at 25 mg L?1, MNPs exhibited high adsorption capacity for As(V) and As (III), 206.9 mg�g?1 and 168.6 mg�g?1 under anaerobic conditions, respectively, and 109.9 mg�g?1 and 108.6 mg�g?1 under aerobic conditions, respectively. Under aerobic conditions, MNPC achieved even higher adsorption capacity than MNP, 165.1 mg�g?1 on As(V) and 157.9 mg�g?1 on As(III). For As(V) at 50 mg L?1, MNPC achieved an adsorption capacity as high as 341.8 mg�g?1, the highest in the literature. A kinetic study indicated that this adsorption reaction can reach equilibrium within 15 min and the rate constant of As(V) is about 1.9 times higher than that of As(III). These results suggested that MNPC can serve as a highly effective adsorbent for fast removal of As.
Chang, Shu-Chi; Yu, Yu-Han; Li, Cheng-Hao; Wu, Chin-Ching; Lei, Hao-Yun
Silane coupling agent for attaching fusion-bonded epoxy to steel.
We describe the possibility of using ?-aminopropyltriethoxysilane (?-APS) to increase the durability of epoxy powder coating/steel joints. The curing temperature of epoxy powder coatings is frequently above 200 �C, which is seen so far as a major limitation for the use of the heat-sensitive aminosilane coupling agent. Despite this limitation, we demonstrate that aminosilane is a competitive alternative to traditional chromate conversion to enhance the durability of epoxy powder coatings/steel joints. Fourier-transform reflection-absorption infrared spectroscopy (FT-RAIRS), X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM) were used to identify the silane deposition conditions that influence the adhesion of epoxy powder coatings on steel. We show that AFM analysis provides highly sensitive measurements of mechanical property development and, as such, the degree of condensation of the silane. The joint durability in water at 60 �C was lower when the pH of the ?-APS solution was controlled at 4.6 using formic acid, rather than that at natural pH (10.6). At the curing temperature of 220 �C, oxidation of the carbon adjacent to the amine headgroup of ?-APS gives amide species by a pseudofirst-order kinetics. However, a few amino functionalities remain to react with oxirane groups of epoxy resin and, thus, strengthen the epoxy/silane interphase. The formation of ammonium formate in the acidic silane inhibits the reaction between silane and epoxy, which consequently decreases the epoxy/silane interphase cohesion. We find that the nanoroughness of silane deposits increases with the cure temperature which is beneficial to the wet stability of the epoxy/steel joints, due to increased mechanical interlocking. PMID:23790122
Tchoquessi Diodjo, Madeleine R; Belec, L�na�k; Aragon, Emmanuel; Joliff, Yoann; Lanarde, Lise; Perrin, Fran�ois-Xavier
Effects of coupling agents on dynamic mechanical properties of aged and wet multi-functional epoxy resins cured with acid anhydrides and filled with pitch based carbon short fibers treated with coupling agents
Pitch-based carbon short fibers (PCF) as functional fillers were treated with five types of coupling agents (CA) and were filled with multi-functional epoxy resin (EP) cured with three types of acid anhydrides at 22.2 wt%. The influence of aging and wetting on the dynamic mechanical properties was studied by use of a non-resonant forced-vibration method. The samples were aged at
Muneaki Yamaguchi; Yuko Tanaka; Katsutoshi Tanaka
Influence of silane coupling agent on morphology and dielectric property in BaTiO3/polyvinylidene fluoride composites
Surface of BaTiO3 particle was chemically modified using silane coupling agent (KH550) in order to improve its compatibility with polyvinylidene fluoride (PVDF) matrix polymer, and therefore, expectable microstructure and dielectric property of the BaTiO3/PVDF composites were acquired. Infrared spectra reveal an obvious interaction between BaTiO3 and PVDF induced by the addition of KH550 coupling agent, and the interaction was also confirmed by the observation of morphology of fractured surface of the BaTiO3/PVDF composite when the concentration of KH550 is around 1.0 wt %. Crystal lattice parameter of BaTiO3 in the composite was also changed because of the interaction. Finally, increased dielectric constant in the PVDF matrix composite with BaTiO3 treated by 1.0 wt % KH550 was found.
Dang, Zhi-Min; Wang, Hai-Yan; Xu, Hai-Ping
Thermal and Mechanical Evaluation of Epoxy Resin Composites by Synthesis of Amine-Based Coupling Agent-Nano Silica Complex
A chemical route was developed for pre-treatment of silica nano particles, prior to introducing the filler into the epoxy matrix in order to improve the compatibility of these phases. Silica nanoparticles were reacted with n-(2-aminoethyl)-3-aminopropyltrimethoxysilane (AEAP) coupling agent. The nanophase organic-inorganic complex was introduced into an epoxy-based polymer system. Effect of complexation was investigated on dispersion quality of nanoparticles in
Mir Mohammad Alavi Nikje; Amir Bagheri Garmarudi; Zahra Mazaheri Tehrani; Moslem Haghshenas; Saeed Shakhesi
Effects of silane coupling agents on internal reinforcement of wood by E-glass and basalt fibers
The internal reinforcement of Douglas-fir by glass or basalt fibers impregnated with resorcinol-phenol-formaldehyde or polymeric diphenylmethanediisocyanate bonding resins has been investigated. The objective was to evaluate the improvement in composite properties by the use of silane coupling agents. Fibers were treated with 3-(4-methoxyphenyl) propyl methyldichlorosilane for use with the phenolic resin, and with 3-aminopropyl triethoxysilane for use with the isocyanate
J.-M. Park; R. V. Subramanian
Dispersion of nonaqueous Co 2Z ferrite powders with titanate coupling agent and poly(vinyl butyral)
Co 2Z ferrite powders with the chemical composition 3Ba 0.5Sr 0.5O�2CoO�12Fe 2O 3 have superior high frequency magnetic properties. However, Co 2Z ferrite powders are difficult to apply to practical processes because of agglomeration induced by the strong magnetic attraction between particles. In this study, Co 2Z ferrite powders pretreatment using a titanate coupling agent - neopentyl(dially)oxy tri(dioctyl)pyrophosphate titanate (Lica 38) on the sedimentation and rheological behavior is investigated. The bonding mechanisms between ferrite powder, Lica 38, and poly(vinyl butyral) (PVB) are studied using diffuse reflectance Fourier transform infrared spectroscopy is used to explain the difference in the rheological and sedimentation behaviors of untreated and titanate coupling agent-modified ferrite powders. The affinity of Co 2Z ferrite and PVB could be substantially enhanced by coating a titanate coupling agent onto the ferrite surface. The coated layer could prevent particles from agglomeration induced by the magnetic interaction.
Hsiang, Hsing-I.; Chen, Chih-Cheng; Tsai, Jaw-Yue
Attaching Biological Probes to Silica Optical Biosensors Using Silane Coupling Agents
In order to interface with biological environments, biosensor platforms, such as the popular Biacore system (based on the Surface Plasmon Resonance (SPR) technique), make use of various surface modification techniques, that can, for example, prevent surface fouling, tune the hydrophobicity / hydrophilicity of the surface, adapt to a variety of electronic environments, and most frequently, induce specificity towards a target of interest.1-5 These techniques extend the functionality of otherwise highly sensitive biosensors to real-world applications in complex environments, such as blood, urine, and wastewater analysis.2,6-7 While commercial biosensing platforms, such as Biacore, have well-understood, standard techniques for performing such surface modifications, these techniques have not been translated in a standardized fashion to other label-free biosensing platforms, such as Whispering Gallery Mode (WGM) optical resonators.8-9 WGM optical resonators represent a promising technology for performing label-free detection of a wide variety of species at ultra-low concentrations.6,10-12 The high sensitivity of these platforms is a result of their unique geometric optics: WGM optical resonators confine circulating light at specific, integral resonance frequencies.13 Like the SPR platforms, the optical field is not totally confined to the sensor device, but evanesces; this "evanescent tail" can then interact with species in the surrounding environment. This interaction causes the effective refractive index of the optical field to change, resulting in a slight, but detectable, shift in the resonance frequency of the device. Because the optical field circulates, it can interact many times with the environment, resulting in an inherent amplification of the signal, and very high sensitivities to minor changes in the environment.2,14-15 To perform targeted detection in complex environments, these platforms must be paired with a probe molecule (usually one half of a binding pair, e.g. antibodies / antigens) through surface modification.2 Although WGM optical resonators can be fabricated in several geometries from a variety of material systems, the silica microsphere is the most common. These microspheres are generally fabricated on the end of an optical fiber, which provides a "stem" by which the microspheres can be handled during functionalization and detection experiments. Silica surface chemistries may be applied to attach probe molecules to their surfaces; however, traditional techniques generated for planar substrates are often not adequate for these three-dimensional structures, as any changes to the surface of the microspheres (dust, contamination, surface defects, and uneven coatings) can have severe, negative consequences on their detection capabilities. Here, we demonstrate a facile approach for the surface functionalization of silica microsphere WGM optical resonators using silane coupling agents to bridge the inorganic surface and the biological environment, by attaching biotin to the silica surface.8,16 Although we use silica microsphere WGM resonators as the sensor system in this report, the protocols are general and can be used to functionalize the surface of any silica device with biotin.
Soteropulos, Carol E.; Hunt, Heather K.
Attaching biological probes to silica optical biosensors using silane coupling agents.
In order to interface with biological environments, biosensor platforms, such as the popular Biacore system (based on the Surface Plasmon Resonance (SPR) technique), make use of various surface modification techniques, that can, for example, prevent surface fouling, tune the hydrophobicity/hydrophilicity of the surface, adapt to a variety of electronic environments, and most frequently, induce specificity towards a target of interest. These techniques extend the functionality of otherwise highly sensitive biosensors to real-world applications in complex environments, such as blood, urine, and wastewater analysis. While commercial biosensing platforms, such as Biacore, have well-understood, standard techniques for performing such surface modifications, these techniques have not been translated in a standardized fashion to other label-free biosensing platforms, such as Whispering Gallery Mode (WGM) optical resonators. WGM optical resonators represent a promising technology for performing label-free detection of a wide variety of species at ultra-low concentrations. The high sensitivity of these platforms is a result of their unique geometric optics: WGM optical resonators confine circulating light at specific, integral resonance frequencies. Like the SPR platforms, the optical field is not totally confined to the sensor device, but evanesces; this "evanescent tail" can then interact with species in the surrounding environment. This interaction causes the effective refractive index of the optical field to change, resulting in a slight, but detectable, shift in the resonance frequency of the device. Because the optical field circulates, it can interact many times with the environment, resulting in an inherent amplification of the signal, and very high sensitivities to minor changes in the environment. To perform targeted detection in complex environments, these platforms must be paired with a probe molecule (usually one half of a binding pair, e.g. antibodies/antigens) through surface modification. Although WGM optical resonators can be fabricated in several geometries from a variety of material systems, the silica microsphere is the most common. These microspheres are generally fabricated on the end of an optical fiber, which provides a "stem" by which the microspheres can be handled during functionalization and detection experiments. Silica surface chemistries may be applied to attach probe molecules to their surfaces; however, traditional techniques generated for planar substrates are often not adequate for these three-dimensional structures, as any changes to the surface of the microspheres (dust, contamination, surface defects, and uneven coatings) can have severe, negative consequences on their detection capabilities. Here, we demonstrate a facile approach for the surface functionalization of silica microsphere WGM optical resonators using silane coupling agents to bridge the inorganic surface and the biological environment, by attaching biotin to the silica surface. Although we use silica microsphere WGM resonators as the sensor system in this report, the protocols are general and can be used to functionalize the surface of any silica device with biotin. PMID:22588224
Soteropulos, Carol E; Hunt, Heather K
A coupled method based on multi-agent model, remote sensing and GIS is described to simulate the forest disease spread. The coupled model focuses on the temporal dynamics of the Bursaphelenchus xylophilus population at the landscape scale. Each individual is modeled as an autonomous agent who behaves according to a set of rules including spreading in the landscape, feeding on Pinus massoniana, sheltering in forest edges and dying, constrained by terrain, land cover and other variables. The model parameters are derived from remote sensing data and field measurements. Ten factors, including damage degree of Pinus Massoniana, altitude and slope, are helped to build the transfer rules. The main outputs are the dynamic disease distribution maps and survived pine population. Our method is applied and validated in DingHai distinct, Zhou Shan city of Zhejiang Province. Three Landsat TM images from the year 1991 to 2006 are used for the pine information extraction. The extracted pine distribution map is used to compare with the simulated surviving pine map. The results show that the coupled model can produce reasonable results and be used as a virtual experiment tool. However, it is difficult to simulate the human activities to help or prevent disease spread and the long fly behavior of insect vectors. Therefore, there still exists some difference between the simulated results and the real data. At the next step, those factors will be considered.
Huang, Huaguo; Wang, Lei; Zhang, XiaoLi; Luo, YouQing; Zhao, Liqiong
Direct Formation of Silane Coupling Agents on Glass for Improved Composite Performance.
This research resulted in the formation of hydrolytically stable, grafted silane coupling layers on glass surfaces. This was be accomplished by: (1) hydrogenation of glass substrates: (2) synthesis of aminoalkenes; and (3) reaction of aminoalkenes with th...
D. A. Boyles J. Kellar W. Cross
Properties of Paper Sludge Filled Polypropylene (PP)\\/Ethylene Propylene Diene Terpolymer (EPDM) Composites: The Effect of Silane-Based Coupling Agent
Paper sludge was used as a filler in PP\\/EPDM composites and 3-aminopropyl triethoxysilane (3-APE) was used in this study as a coupling agent. The effects of filler loading and 3-APE on the mechanical properties, water absorption, morphology, and thermal properties of the composites were investigated. It was found that incorporation of a silane coupling agent (3-APE) increased the stabilization (equilibrium)
H. Ismail; A. Abu Bakar
Effects of the Treatment of Al(OH)3 by a Silane Coupling Agent on the Tensile Properties of PVC\\/Al(OH)3 Composite
The present work deals with the study of a composite based on poly(vinyl chloride) (PVC) and aluminum hydroxide (Al(OH)3) which is treated with different concentrations of the silane coupling agent N-(2-aminoethyl)-3-aminopropyltrimethoxysilane.The composites containing untreated Al(OH)3 and those treated with the coupling agent were prepared by melt mixing using a two-roll mill.Analysis of the treated filler by means of Fourier Transform
S. Benmesli; F. Riahi; R. Doufnoune
Synthesis of silica-coated ZnO nanocomposite: the resonance structure of polyvinyl pyrrolidone (PVP) as a coupling agent
The preparation of silica-coated ZnO nanocomposite using polyvinyl pyrrolidone (PVP) as a coupling agent was investigated.\\u000a Transmission electron microscopy analysis revealed that silica has been deposited on the surface of PVP-capped ZnO nanoparticles\\u000a as a continuous thin layer. Two-dimensional correlation analysis based on the time-dependent UV�vis spectra was introduced\\u000a to study the interaction governing the deposition of silica on to
Jinfeng Wang; Takuya Tsuzuki; Bin Tang; Pavel Cizek; Lu Sun; Xungai Wang
Promotion of couples' voluntary HIV counselling and testing in Lusaka, Zambia by influence network leaders and agents
Objectives Hypothesising that couples� voluntary counselling and testing (CVCT) promotions can increase CVCT uptake, this study identified predictors of successful CVCT promotion in Lusaka, Zambia. Design Cohort study. Setting Lusaka, Zambia. Participants 68 influential network leaders (INLs) identified 320 agents (INAs) who delivered 29?119 CVCT invitations to heterosexual couples. Intervention The CVCT promotional model used INLs who identified INAs, who in turn conducted community-based promotion and distribution of CVCT invitations in two neighbourhoods over 18?months, with a mobile unit in one neighbourhood crossing over to the other mid-way through. Primary outcome The primary outcome of interest was couple testing (yes/no) after receipt of a CVCT invitation. INA, couple and invitation characteristics predictive of couples� testing were evaluated accounting for two-level clustering. Results INAs delivered invitations resulting in 1727 couples testing (6% success rate). In multivariate analyses, INA characteristics significantly predictive of CVCT uptake included promoting in community-based (adjusted OR (aOR)=1.3; 95% CI 1.0 to 1.8) or health (aOR=1.5; 95% CI 1.2 to 2.0) networks versus private networks; being employed in the sales/service industry (aOR=1.5; 95% CI 1.0 to 2.1) versus unskilled manual labour; owning a home (aOR=0.7; 95% CI 0.6 to 0.9) versus not; and having tested for HIV with a partner (aOR=1.4; 95% CI 1.1 to 1.7) or alone (aOR=1.3; 95% CI 1.0 to 1.6) versus never having tested. Cohabiting couples were more likely to test (aOR=1.4; 95% CI 1.2 to 1.6) than non-cohabiting couples. Context characteristics predictive of CVCT uptake included inviting couples (aOR=1.2; 95% CI 1.0 to 1.4) versus individuals; the woman (aOR=1.6; 95% CI 1.2 to 2.2) or couple (aOR=1.4; 95% CI 1.0 to 1.8) initiating contact versus the INA; the couple being socially acquainted with the INA (aOR=1.6; 95% CI 1.4 to 1.9) versus having just met; home invitation delivery (aOR=1.3; 95% CI 1.1 to 1.5) versus elsewhere; and easy invitation delivery (aOR=1.8; 95% CI 1.4 to 2.2) versus difficult as reported by the INA. Conclusions This study demonstrated the ability of influential people to promote CVCT and identified agent, couple and context-level factors associated with CVCT uptake in Lusaka, Zambia. We encourage the development of CVCT promotions in other sub-Saharan African countries to support sustained CVCT dissemination.
Wall, Kristin M; Kilembe, William; Nizam, Azhar; Vwalika, Cheswa; Kautzman, Michelle; Chomba, Elwyn; Tichacek, Amanda; Sardar, Gurkiran; Casanova, Deborah; Henderson, Faith; Mulenga, Joseph; Kleinbaum, David; Allen, Susan
Monomolecular layers and thin films of silane coupling agents by vapor-phase adsorption on oxidized aluminum
Thin films of tetraethoxysilane [TEOS], (3-bromopropyl)trimethoxysilane [BPS], trimethoxyvinylsilane [VS], and 3-(trimethoxysilyl) propyl methacrylate [TPM] on oxidized aluminum surfaces have been investigated by reflection-absorption FTIR spectroscopy, ellipsometry, contact angle, and quartz crystal microbalance (QCM) measurements. Gravimetric measurements with the QCM can reveal quantitative aspects of adsorption and film formation, even for films as thin as monolayers. Adsorption of these silane coupling agents from solution typically produces multilayer films. Vapor-phase adsorption of TEOS and TPM at room temperature results in monomolecular layers. The coupling agents VS and BPS require additional heating after the vapor-phase adsorption to initiate the hydrolysis and condensation reactions necessary for the surface attachment, which produces one to three layers. For vapor adsorbed films a packing density of 4-7 molecules/nm{sup 2} was found. The data strongly suggest that the organic moieties in several of these films have a preferential orientation on the surface; they can be viewed as two-dimensional, oligomeric siloxane networks with oriented organic chains. Subsequent heating of TPM films results in structural rearrangements; heating of TEOS results in complete condensation to SiO{sub 2} films. 43 refs., 6 figs., 4 tabs.
Kurth, D.G.; Bein, T. [Purdue Univ., West Lafayette, IN (United States)
Investigation of oil recovery improvement by coupling an interfacial tension agent and a mobility control agent in light oil reservoirs. Summary annual report, October 1994--September 1995.
The study will investigate two major areas concerning co-injecting an interfacial tension reduction agent(s) and a mobility control agent into petroleum reservoirs. The first will consist of defining the mechanisms of interaction of an alkaline agent, a s...
M. J. Pitts
Modified coupling agents based on thiourea, immobilized onto silica. Thermodynamics of copper adsorption
New silylating agents synthesized by incorporating the thiourea molecule into precursor agents containing increasing numbers of basic nitrogen atoms, 3-aminopropyltriethoxysilane, N-[3-(trimethoxysilyl)propyl]-ethylenediamine and N-[3-(trimethoxysilyl)propyl]diethylenetri-amine, through a solvent-free methodology were characterized before being successfully immobilized onto silica gel. The spectroscopic results support the elemental analysis, demonstrating that the thiourea molecule reacted in such a way as to maintain free amino groups. NMR data for carbon and silicon nuclei eflucidated the structural features associated with the incorporated chains and their bonds to the silica skeleton, with formation of covalent silicon-carbon bonds. Thermogravimetric data correlated with the degree of functionalization, which was also obtained from elemental analysis. The available basic nitrogen and sulfur atoms attached to the incorporated pendant chains have the ability to coordinate copper to give 1.10, 0.47 and 1.25 mmol g -1 as maximum adsorption capacities for the samples prepared with the silanes containing one, two and three nitrogen atoms on their structures. The thermodynamic data for copper/basic center interactions at the solid/liquid interface were determined through calorimetric titration, and the set of data demonstrated favorable systems for all three newly synthesized derivatized silicas, as shown by exothermic enthalpic data, which yield negative Gibbs free energies for removal of this cation from aqueous solutions by all the newly synthesized materials.
Oliveira, Fernando J. V. E.; da Silva Filho, Edson C.; Melo, Maur�cio A., Jr.; Airoldi, Claudio
Investigation of oil recovery improvement by coupling an interfacial tension agent and a mobility control agent in light oil reservoirs. Final report
This research studied the oil recovery potential of flooding light oil reservoirs by combining interfacial tension reducing agent(s) with a mobility control agent. The specific objectives were: To define the mechanisms and limitations of co-injecting interfacial tension reduction agent(s) and a mobility control agent to recover incremental oil. Specifically, the study focused on the fluid-fluid and fluid-rock interactions. To evaluate the economics of the combination technology and investigate methods to make the process more profitable. Specific areas of study were to evaluate different chemical concentration tapers and the volume of chemical injection required to give optimal oil recovery.
Pitts, M.
Investigation of oil recovery improvement by coupling an interfacial tension agent and a mobility control agent in light oil reservoirs. Technical progress report, January--March 1994
The study will investigate two major areas concerning co-injecting an interfacial tension reduction agent(s) and a mobility control agent into petroleum reservoirs. The first will consist of defining the mechanisms of interaction of an alkaline agent, a surfactant, and a polymer on a fluid-fluid and a fluid-rock basis. The second is the improvement of the economics of the combined technology. This report examines the adsorption of alkali, surfactant, and polymer onto crushed Berea sandstone.
Investigation of oil recovery improvement by coupling an interfacial tension agent and a mobility control agent in light oil reservoirs. Technical progress report, September--December 1993
Investigation of oil recovery improvement by coupling an interfacial tension agent and a mobility control agent in light oil reservoirs. Summary annual report, October 1994September 1995
The study will investigate two major areas concerning co-injecting an interfacial tension reduction agent(s) and a mobility control agent into petroleum reservoirs. The first will consist of defining the mechanisms of interaction of an alkaline agent, a surfactant, and a polymer on a fluid-fluid and a fluid-rock basis. The second is the improvement of the economics of the combined technology.
Surface modification of organic polymers with bioactive titanium oxide without the aid of a silane-coupling agent.
Polyethylene (PE), polyethylene terephthalate (PET), ethylene-vinyl alcohol copolymer (EVOH), and poly(epsilon-caprolactam) (Nylon 6) were successfully modified with a thin crystalline titanium oxide layer on their surfaces by a simple dipping into a titanium alkoxide solution and a subsequent soak in hot HCl solution, without the aid of a silane-coupling agent. The surface modified polymers formed a bone-like apatite layer in a simulated body fluid (SBF) within a period of 2 days. PE, PET, and Nylon 6 formed an apatite layer faster and had a higher adhesive strength to the apatite. Three-dimensional fabrics with open spaces in various sizes containing such surface modified polymer fibers are expected to be useful as bone substitutes, since they may be able to form apatite on their constituent fibers in the living body, and thus, integrate with living bone. PMID:17277978
Balas, F; Kokubo, T; Kawashita, M; Nakamura, T
Lubrication of Si 3N 4 and Al 2O 3 in water with and without addition of silane coupling agents in the range of 0.05�0.10 mol\\/l
To improve water lubrication of ceramics at a lower sliding velocity, the effect of the addition of silane coupling agents was investigated. Si3N4 and Al2O3 were slid against themselves in water with and without the addition of silane coupling agents in amounts ranging from 0.05 to 0.10 mol\\/l. Silane coupling agents containing one or more amino groups were effective in
Yuko Hibi; Yuji Enomoto
Investigation of oil recovery improvement by coupling an interfacial tension agent and a mobility control agent in light oil reservoirs. Technical progress report, October--December 1994
The study will investigate two major areas concerning co-injecting an interfacial tension reduction agent(s) and a mobility control agent into petroleum reservoirs. The first will consist of defining the mechanisms of interaction of an alkaline agent, a surfactant, and a polymer on a fluid-fluid and a fluid-rock basis. The second is the improvement of the economics of the combined technology. This report examines effect of rock type on oil recovery by an alkaline-surfactant-polymer solutions. This report also begins a series of evaluations to improve the economics of alkaline-surfactant-polymer oil recovery.
Exfoliated graphite nanoplatelet-filled impact modified polypropylene nanocomposites: influence of particle diameter, filler loading, and coupling agent on the mechanical properties
Exfoliated graphite nanoplatelets (xGnP)-filled impact-modified polypropylene (IMPP) composites were prepared at 2, 4, 6, and 8 wt % xGnP with and without the addition of a coupling agent and manufactured using melt mixing followed by injection molding. The coupling agent used in this study was polypropylene-graft-maleic anhydride (PP-g-MA). The nanoparticles used were xGnP with three different sizes: xGnP5 has an average thickness of 10 nm, and an average platelet diameter of 5 ?m, whereas xGnP15 and xGnP25 have the same thickness but average diameters are 15 and 25 ?m, respectively. Test results show that nanocomposites with smaller xGnP diameter exhibited better flexural and tensile properties for both neat and compatibilized composites. For composites containing a coupling agent, tensile and flexural modulus and strength increased with the addition of xGnP. In the case of neat composites, both tensile and flexural modulus and strength decreased at higher filler loading levels. Increasing xGnP loading resulted in reduction of elongation at break for both neat and composites containing coupling agent. Explanation of this brittle behavior in a nanoplatelet-filled IMPP is presented using scanning electron microscopy and transmission electron microscopy.
Duguay, Alex J.; Nader, Jacques W.; Kiziltas, Alper; Gardner, Douglas J.; Dagher, Habib J.
Influence of Electron Beam Irradiation and Coupling Agents on the Thermal Stability of Sugar Cane Bagasse Fiber-Thermoplastics Scrape Composite
The influence of blending of sugar cane bagasse with thermoplastics scrape as well as incorporation of some coupling agents has been conducted using thermogravimetric analysis (TGA). In addition, the effect of electron beam preirradiation of low density polyethylene on the properties of the bagasse-LDPE composite was also studied. Simulation of TGA data reveals that the presence of bagasse fiber accelerates
H. A. Youssef; M. A. M. Ali; M. R. Ismail; A. H. Zahran
Investigation of oil recovery improvement by coupling an interfacial tension agent and a mobility control agent in light oil reservoirs. Technical progress report, July 1995--September 1995
This study will investigate two major areas concerning co-injection and interfacial tension reduction agents and a mobility control agent into petroleum reservoirs. The first will consist of defining the mechanisms of interaction of an alkaline agent, a surfactant, and a polymer on a fluid-fluid and a fluid-rock basis. The second is the improvement of the economics of the combined technology. This report examines altering the concentration of alkali and polymer on the oil recovery economics of alkaline-surfactant-polymer solution.
The surface modification of TiN nano-particles using macromolecular coupling agents, and their resulting dispersibility
Titanium nitride (TiN) nano-particles were modified by the grafting of a random copolymerization functionalized macromolecular coupling agent (F-MCA) via a direct blending method. The hydroxyl groups on the surface of the nano-TiN particles interact with the silanol groups [SiOCH3] of the F-MCA to form an organic coating layer. The formation of covalent bonds [TiOSi] was verified using Fourier transform infrared spectroscopy. An X-ray diffraction analysis suggests that the presence of the F-MCA inhibited the growth of the crystal plane but did not change the crystal structure of the TiN. Thermogravimetric analysis and contact angle measurement indicated that the F-MCA molecules were adsorbed or anchored to the surface of the nano-TiN particles, which hindered their aggregation. Pristine nano-TiN particles are poorly dispersed in ethyl acetate. Compared with the pristine TiN particles, the modified TiN particles show good dispersibility and form a stable colloidal dispersion in ethyl acetate. The surface hydrophobicity of the modified TiN increases, and the F-MCA molecules are anchored on the surface of the TiN particles. TiN particles modified by a F-MCA can be used in polymer blends, thermoplastic elastomers and polymer nanocomposites that have a better performance and longer life cycle.
Cheng, Guojun; Qian, Jiasheng; Miao, Jibin; Yang, Bin; Xia, Ru; Chen, Peng
Investigation of oil recovery improvement by coupling an interfacial tension agent and a mobility control agent in light oil reservoirs. Technical progress report, April--June 1994
The study will investigate two major areas concerning co-injecting an interfacial tension reduction agent(s) and a mobility control agent into petroleum reservoirs. The first will consist of defining the mechanisms of interaction of an alkaline agent, a surfactant, and a polymer on a fluid-fluid and a fluid-rock basis. The second is the improvement of the economics of the combined technology. This report examines the changes in the relative permeability characteristics with addition of alkali, surfactant, and polymer to the injected solution, the effect of matrix type on relative permeability characteristics with alkali-surfactant-polymer and the effect of different polymer concentrations on oil recovery by an alkaline-surfactant-polymer solution.
Pitts, M.J.; Casteel, J.
Improve the Strength of PLA/HA Composite Through the Use of Surface Initiated Polymerization and Phosphonic Acid Coupling Agent
Bioresorbable composite made from degradable polymers, e.g., polylactide (PLA), and bioactive calcium phosphates, e.g., hydroxyapatite (HA), are clinically desirable for bone fixation, repair and tissue engineering because they do not need to be removed by surgery after the bone heals. However, preparation of PLA/HA composite from non-modified HA usually results in mechanical strength reductions due to a weak interface between PLA and HA. In this study, a calcium-phosphate/phosphonate hybrid shell was developed to introduce a greater amount of reactive hydroxyl groups onto the HA particles. Then, PLA was successfully grafted on HA by surface-initiated polymerization through the non-ionic surface hydroxyl groups. Thermogravimetric analysis indiated that the amount of grafted PLA on HA can be up to 7 %, which is about 50 % greater than that from the literature. PLA grafted HA shows significantly different pH dependent ?-potential and particle size profiles from those of uncoated HA. By combining the phosphonic acid coupling agent and surface initiated polymerization, PLA could directly link to HA through covalent bond so that the interfacial interaction in the PLA/HA composite can be significantly improved. The diametral tensile strength of PLA/HA composite prepared from PLA-grafted HA was found to be over twice that of the composite prepared from the non-modified HA. Moreover, the tensile strength of the improved composite was 23 % higher than that of PLA alone. By varying additional variables, this approach has the potential to produce bioresorbable composites with improved mechanical properties that are in the range of natural bones, and can have wide applications for bone fixation and repair in load-bearing areas.
Wang, Tongxin; Chow, Laurence C.; Frukhtbeyn, Stanislav A.; Ting, Andy Hai; Dong, Quanxiao; Yang, Mingshu; Mitchell, James W.
Investigation of oil recovery improvement by coupling an interfacial tension agent and a mobility control agent in light oil reservoirs. Summary annual report, October 1994--September 1995
The study will investigate two major areas concerning co-injecting an interfacial tension reduction agent(s) and a mobility control agent into petroleum reservoirs. The first will consist of defining the mechanisms of interaction of an alkaline agent, a surfactant, and a polymer on a fluid-fluid and a fluid-rock basis. The second is the improvement of the economics of the combined technology. The third year of the study finished the oil recovery coreflood studies and evaluated different techniques to improve alkaline-surfactant-polymer solution economics. The final series of corefloods compared the oil recovery efficiency of the alkali gradient in Berea sandstone and J Sand sandstone. Oil recovery efficiency was essentially the same in both types of core, 13 to 15% PV of oil. Cost of chemical per incremental barrel of oil with 30% pore volume of alkaline-surfactant- polymer solution injected were $3.20 for the Na{sub 2}CO{sub 3}- Petrostep B-100-Flopaam 3330S solution in both types of core.
Dynamic mechanical properties of multi-functional epoxy resin cured with diamine and filled with pitch-based carbon short fibers treated with coupling agents
We have been conducting research on the development of heat-resistant composite materials filled with functional short fibers in multi-functional epoxy resin. As part of such effort, the filling effects of pitch-based carbon short fibers were investigated. In addition, the effects of treatment of coupling agents were studied by filling treated fibers into matrices cured with acid anhydride taking the large
Katsutoshi Tanaka; Muneaki Yamaguchi
The Effect of Bis(3-triethoxysilylpropyl) Tetrasulphide (Si69) as a Coupling Agent on Properties of Natural Rubber\\/Kenaf Fibre Composites
Kenaf fiber-filled natural rubber composites with and without Bis-(3-triethoxysilylpropyl) tetrasulphide as a coupling agent at different kenaf loading i.e., 0, 10, 20, 30 and 40�phr were prepared. The natural rubber composites were cured at 150�C according to their cure time. Curing characteristics, tensile properties, rubber-filler interaction and morphological properties of the kenaf fiber-filled natural rubber composites were studied. Scorch time
Hanafi Ismail; Norjulia Ahmad Mahir; Zulkifli Ahmad
Influence of storage time and temperature and silane coupling agent on bound rubber formation in filled styrene�butadiene rubber compounds
Bound rubber reflects the filler�polymer interactions involving physical adsorption, chemisorption, and mechanical interaction. For silica-filled rubber compounds, silane coupling agent is used to improve the filler dispersion. In the present work, variation of the bound rubber content with the storage time was studied using styrene�butadiene rubber (SBR) compounds filled with silica or carbon black. Influence of the silane content on
Sung-Seen Choi
Enhanced heat transfer through filler-polymer interface by surface-coupling agent in heat-dissipation material: A non-equilibrium molecular dynamics study
Developing a composite material of polymers and micrometer-sized fillers with higher heat conductance is crucial to realize modular packaging of electronic components at higher densities. Enhancement mechanisms of the heat conductance of the polymer-filler interfaces by adding the surface-coupling agent in such a polymer composite material are investigated through the non-equilibrium molecular dynamics (MD) simulation. A simulation system is composed of ?-alumina as the filler, bisphenol-A epoxy molecules as the polymers, and model molecules for the surface-coupling agent. The inter-atomic potential between the ?-alumina and surface-coupling molecule, which is essential in the present MD simulation, is constructed to reproduce the calculated energies with the electronic density-functional theory. Through the non-equilibrium MD simulation runs, we find that the thermal resistance at the interface decreases significantly by increasing either number or lengths of the surface-coupling molecules and that the effective thermal conductivity of the system approaches to the theoretical value corresponding to zero thermal-resistance at the interface. Detailed analyses about the atomic configurations and local temperatures around the interface are performed to identify heat-transfer routes through the interface.
Tanaka, Kouichi; Ogata, Shuji; Kobayashi, Ryo; Tamura, Tomoyuki; Kitsunezuka, Masashi; Shinma, Atsushi
Bostrycin, a novel coupling agent for protein immobilization and prevention of biomaterial-centered infection produced by Nigrospora sp. No. 407.
Bostrycin, a red antibacterial agent with tetrahydroanthraquinone structure, has been isolated from Nigrospora sp. No. 407. This study investigated the potential antibacterial and multifunctional properties of matrixes through immobilization of bostrycin on their surface for immobilization of protein and prevention of bacterial growth. Bostrycin was immobilized on nonwoven polypropylene (PP) fabric by a technique using glutaraldehyde and polyethyleneimine for the activation of the surface. Glucose oxidase immobilized on bostrycin-treated nonwoven PP fabric showed high activity. The immobilization process improved thermal stability of the enzymes. During repeated assay for 30 cycles, the enzyme activity dropped to only 70% of the initial activity. Both bostrycin-treated nonwoven PP fabric sample and subsequently immobilized glucose oxidase sample on the surface also still exhibited a bacteriostatic effect. This is the first study to show that bostrycin is a promising coupling agent for surface modification on matrix and its potential applications in protein immobilization and biomaterial-centered infection. PMID:22500894
Yang, Wen-Jen; Yang, Chih-Sheng; Huang, Chen-Ji; Chen, Ko-Shao; Lin, Shuen-Fuh
Surface Functionalization with Phosphazenes: Part 6. Modification of Polyethylene Co -Polyvinylalcohol Copolymer Surface Plates with Fluorinated Alcohols and Azobenzene Derivatives Using Chlorinated Phosphazenes as Coupling Agents
In this paper we describe a two-step surface modification process of poly(ethylene-co-vinyl alcohol) by exploiting hexachlorocyclophosphazene and poly(dichlorophosphazene) as coupling agents. Part of the P�Cl\\u000a groups of the chlorophosphazenes is first reacted with the surface hydroxylic groups of the substrate to form covalent P�O�C\\u000a bonds, the remaining being utilized for successive substitution reactions with different nucleophiles (i.e. 2,2,2-trifluoroethanol,\\u000a heptadecafluorononanol and
Roberto Milani; Mario Gleria; Silvia Gross; Roger De Jaeger; Ahmed Mazzah; Leon Gengembre; Martine Frere; Charafeddine Jama
Ultrastructural localization of a neutron capture agent utilizing electron energy loss spectroscopy coupled with electron spectroscopic imaging
Neutron capture therapy (NCT) is a binary therapeutic modality with significant potential for the treatment of localized tumors in humans. The NCT relies on selective uptake and/or retention within tumor of a nontoxic neutron capture agent (NCA) containing a neutron capture element such as {sup 10}B and irradiation of the tumor with an appropriate-energy neutron beam. The development of tumor-affinative capture agents is requisite for efficacious NCT, particularly those NCAs that specifically localize to vital organelles such as mitochondria and nuclei. Various methods have been utilized to determine tumor and normal tissue boron levels. Few, however, have successfully localized neutron capture elements, in vivo, at the ultrastructural level, which is crucial for determination of radiation microdosimetry. This paper describes experimental results of NCT on gliosarcomas in rats.
Autry, S.A.; Gandour-Edwards, R.; Boggan, J.E. [Univ. of California, San Francisco, CA (United States)] [and others
Novel One-pot Fabrication of Lab-on-a-Bubble@Ag Substrate without Coupling-agent for Surface Enhanced Raman Scattering
Through in-situ reduction of silver nitrate without using any coupling-agent, a substrate for surface-enhanced Raman scattering (SERS) was prepared by coating silver on hollow buoyant silica microspheres as a lab on a bubble (LoB). The silver coated LoBs (LoBs@Ag) floated on surface of a solution could provide a very convenient platform for the detection of target molecules in the solution. The LoBs@Ag substrate not only immobilized well-distributed Ag nanoparticles on the surface LoBs, but excluded the interference of coupling agents. This yielded high-resolution SERS spectra with excellent reproducibility. The adsorption of crystal violet (CV) on the LoBs@Ag substrate was investigated by means of SERS combined with density functional theory (DFT) calculations. The LoBs@Ag substrate exhibited a remarkable Raman enhancement effect for CV with an enhancement factor of 6.9 � 108 and wide adaptability from dye, pesticide to bio-molecules. On the basis of this substrate, a simple and sensitive SERS method was proposed for the determination of trace organic pollutants or bio-molecules.
Jiang, Jizhou; Ou-Yang, Lei; Zhu, Lihua; Zou, Jing; Tang, Heqing
Prostaglandin E2, a postulated astrocyte-derived neurovascular coupling agent, constricts rather than dilates parenchymal arterioles.
It has been proposed that prostaglandin E(2) (PGE(2)) is released from astrocytic endfeet to dilate parenchymal arterioles through activation of prostanoid (EP(4)) receptors during neurovascular coupling. However, the direct effects of PGE(2) on isolated parenchymal arterioles have not been tested. Here, we examined the effects of PGE(2) on the diameter of isolated pressurized parenchymal arterioles from rat and mouse brain. Contrary to the prevailing assumption, we found that PGE(2) (0.1, 1, and 5 ?mol/L) constricted rather than dilated parenchymal arterioles. Vasoconstriction to PGE(2) was prevented by inhibitors of EP(1) receptors. These results strongly argue against a direct role of PGE(2) on arterioles during neurovascular coupling. PMID:23385200
Dabertrand, Fabrice; Hannah, Rachael M; Pearson, Jessica M; Hill-Eubanks, David C; Brayden, Joseph E; Nelson, Mark T
An IETS study of a silane coupling agent; the interaction of 3-(trimethoxysilyl)propanethiol with aluminium oxide and silver surfaces
The inelastic electron tunnelling spectrum of a silane coupling agent, 3-(trimethoxysilyl)propanethiol, is presented. Approximately monolayer quantities of this silane are present on the barrier oxide of an aluminium-aluminium oxide-metal tunnelling junction, in which the counter electrode is either lead or silver. It is deduced from the IETS spectra that the alkoxy groups of this silane condense with the surface hydroxyl groups. No interaction with the lead is observed but the silver layer clearly reacts with the thiol group of the silane molecule, since the thiol stretching vibration is absent in the spectra, and probably forms the corresponding silver thiolate. The influence of this reaction on the conformation of the bound silane is discussed.
Van Velzen, Peter N. T.
Investigation on pharmacokinetics, tissue distribution and excretion of a novel platinum anticancer agent in rats by Inductively Coupled Plasma Mass Spectrometry (ICP-MS).
Abstract 1.?DN604 is a new platinum agent with encouraging anticancer activity. The present study was to explore the pharmacokinetic profiles, distribution and excretion of platinum in Sprague-Dawley rats after intravenous administration of DN604. A sensitive and selective inductively coupled plasma mass spectrometry (ICP-MS) method was established for determination of platinum in biological specimens. The pharmacokinetic parameters were calculated by a non-compartmental method. 2.?The area under concentration-time curve AUC0-t and AUC0-? for platinum originating from DN604 at 10?mg/kg were 25.15?�?1.29 and 28.72?�?1.04??g/hml, respectively. The mean residence time MRT was 36.59?�?6.65?h. The volume of distribution Vz was 11.42?�?2.49?l/kg and clearance CL was 0.18?�?0.01?l/h/kg. In addition, the elimination half-life T1/2z was 44.83?�?9.75?h. After intravenous administration of DN604, platinum was extensively distributed in most of tested tissues except brain. The majority of platinum excreted via urine, and its accumulative excretion ratio during the period of 120?h was 63.5%?�?7.7% for urine, but only 6.94%?�?0.11% for feces. 3.?The satisfactory half-life, wide distribution and high excretion made this novel platinum agent worthy of further research and development. PMID:24524624
Zhao, Jie; Wen, Yanli; Zhang, Wei; Zhao, Di; Fan, Ali; Zhang, Yongjie; Deng, Shuhua; Wang, Xin; Liu, Qingwang; Lu, Yang; Wang, Zhimei; Gou, Shaohua; Chen, Xijing
Determination of six chemotherapeutic agents in municipal wastewater using online solid-phase extraction coupled to liquid chromatography-tandem mass spectrometry.
Due to the increased consumption of chemotherapeutic agents, their high toxicity, carcinogenicity, their occurrence in the aquatic environment must be properly evaluated. An analytical method based on online solid-phase extraction coupled to liquid chromatography-tandem mass spectrometry was developed and validated. A 1mL injection volume was used to quantify six of the most widely used cytotoxic drugs (cyclophosphamide, gemcitabine, ifosfamide, methotrexate, irinotecan and epirubicin) in municipal wastewater. The method was validated using standard additions. The validation results in wastewater influent had coefficients of determination (R(2)) between 0.983 and 0.998 and intra-day precision ranging from 7 to 13% (expressed as relative standard deviation %RSD), and from 9 to 23% for inter-day precision. Limits of detection ranged from 4 to 20ngL(-1) while recovery values were greater than 70% except for gemcitabine, which is the most hydrophilic compound in the selected group and had a recovery of 47%. Matrix effects were interpreted by signal suppression and ranged from 55 to 118% with cyclophosphamide having the highest value. Two of the target anticancer drugs (cyclophosphamide and methotrexate) were detected and quantified in wastewater (effluent and influent) and ranged from 13 to 60ngL(-1). The proposed method thus allows proper monitoring of potential environmental releases of chemotherapy agents. PMID:24388503
Rabii, Farida W; Segura, Pedro A; Fayad, Paul B; Sauv�, S�bastien
Continued investigation of the diazotization and coupling spectrophotometric technique for the determination of aromatic amines with 8-amino-1-hydroxynaphthalene-3,6-disulphonic acid and N-(1-naphthyl)ethylenediamine as coupling agents.
Twenty more aromatic amines are determined by the diazotization and coupling spectrophotometric technique, with 8-amino-1-hydroxynaphthalene-3,6-disulphonic acid (H-acid) and N-(1-naphthy)ethylenediamine (N-na) as coupling agents. The following are determined by both methods: 2,4-diaminotoluene, 2-aminobenzotrifluoride, 4-benzoxyaniline, 2,4-dimethyl-6-nitroaniline, 4,5-dimethyl-2-nitroaniline, 2-amino-9-fluorenone, naphthionic acid (sodium salt), 3-aminonaphthalene-2, 7-disulphonic acid (monosodium salt), 2-aminonaphthalene-1-sulphonic acid, 4-aminonaphthalene-1-sulphonic acid and 2,4-dibromoaniline. The following are determined only by the N-na method: 5-aminosalicylic acid, 2-amino-4-nitrophenol, 4-amino-2,6-dichlorophenol hydrochloride, 2,5-dimethoxy-aniline, 4-aminothiophenol, 4,4'-diaminodiphenylmethane, 1-naphthylamine, 4,4'-diaminobiphenyl-2,2'-disulphonic acid and 4,4'-diaminostilbine-2,2'-disulphonic acid. The optimum acidities for the different aromatic amines for the N-na method vary considerably. A number of aromatic amines cannot be determined by either method. PMID:18964089
Norwitz, G; Keliher, P N
Adsorption of benzoic acid on pure and cupric ion-modified hydroxyapatite: implications for design of a coupling agent to dental polymer composites.
The adsorption isotherms of benzoic acid on synthetic hydroxyapatite (containing about 1.5 monolayers of physisorbed water) were studied from ethanol, dimethylsulfoxide, p-dioxane, methylene chloride, and benzene to discern the role of solvent in the process. The adsorption is reversible from the first three solvents and follows the Langmuir plots. It is irreversible from the last two, and a constant amount of absorbent is removed from solutions above a certain concentration. The isotherms of potassium benzoate on the apatite from ethanol and dimethyl sulfoxide were reversible. The isotherms of the acid on cupric ion-modified apatite surfaces from ethanol and benzene were identical with those obtained on the pure hydroxyapatite. This may demonstrate that any "surface chelation" with the cation may not be a significant factor for adsorption to occur. The adsorptive behavior seems to depend upon the interplay of hydrogen-bonding among the solute, the solvent, and the hydrated apatite surface. The capability of a solvent to hydrogen-bond may determine whether adsorption from it will be reversible or irreversible. Based upon its compatibility with a solvent, the benzene ring is upright or lies flat on the surface. The adsorbed molecules rotate about the center of the carboxylate groups which are hydrogen-bonded to the surface. These factors should be considered in designing or selecting a suitable surface-active moiety for a coupling agent between tooth mineral and a restorative resin. PMID:3009580
Misra, D N
Grafting of a functionalized side-chain liquid crystal polymer on carbon fiber surfaces: Novel coupling agents for fiber/polymer matrix composites
The authors studied covalent grafting to functionalized carbon fibers of a specially designed liquid crystalline monomer and its corresponding side-chain liquid crystalline polymer containing pendant chemical functions on their mesogenic groups. From a materials point of view these liquid crystalline compounds could act as coupling agents at fiber/polymer matrix interfaces, offering a mechanism to control composite properties not only through bonding but also through their [open quotes]spontaneous[close quotes] molecular orientation in interfacial regions. The grafting methodology for both monomer and polymer to fiber surfaces involved esterification through carbodiimide chemistry in solution. Carboxylic acid groups found on functionalized carbon fiber surfaces were esterified to phenolic functions in the side chains of the experimental polymer. Following grafting procedures the fibers were analyzed by scanning electron microscopy (SEM) and by contact angle measurements. SEM micrographs of fibers grafted with polymer revealed the presence of strongly attached polymeric material on the graphitic surface after rigorous extraction with polymer solvent. Contact angle measurements and polar/dispersive free energy analysis indicated also a smaller polar component of the surface free energy of fibers possibly due to the hydrophobic polymer backbone grafted on the carbon surfaces. On the basis of results, it is concluded that the esterification reaction grafted the polyphenolic liquid-crystal polymer on graphite fiber surfaces. 24 refs., 8 figs., 4 tabs.
Le Bonheur, V.; Stupp, S.I. (Univ. of Illinois, Urbana, IL (United States))
Solcoseryl, a tissue respiration stimulating agent, significantly enhances the effect of capacitively coupled electric field on the promotion of bone formation around dental implants.
In the present study we examined the combined effect of application of a capacitively coupled electric field (CCEF) and the tissue respiration stimulating agent, Solcoseryl, on the promotion of bone formation around dental implants histologically and mechanically. After a dental implant was inserted into each femur of Japanese white rabbits, Solcoseryl (2 ml/kg) was administered intravenously in the ear vein and a CCEF was applied for 4 h per day for 14 days. The degree of bone formation on microscopic observation, bone contact ratio, bone surface area ratio, and the level of removal torque of the implant in the Solcoseryl- and CCEF-treated group were significantly higher than the respective value in the control group, which had not been treated with Solcoseryl nor CCEF. Thus, the combination of CCEF stimulation and Solcoseryl effectively promoted the formation of new bone. It is suggested that the clinical use of a combination of CCEF stimulation and Solcoseryl for dental implants promotes osseointegration. PMID:12755779
Ochi, Morio; Wang, Pao-Li; Ohura, Kiyoshi; Takashima, Shigenori; Kagami, Hiroyuki; Hirose, Yukito; Kaku, Tohru; Sakaguchi, Kunihiko
Infrared analysis of the effect of composition of silane blends of amino and alkyl silane blends in tertiary amine-catalyzed anhydride-cured epoxy mixtures. Technical report
The property enhancement caused by silane coupling agents in glass-reinforced epoxy matrices is a function of the structure and composition of the silane. The effect of hydrolyzed and nonhydrolyzed of various compositions of silane coupling agent blends of gamma aminopropyltriethoxysilane (APS) and either butyltriethoxysilane (BTS) or ethyltriethoxysilane (ETS) on the cure of a benzyldimethylamine (BDMA)-catalyzed, nadic methyl anhydride (NMA) cured diglycidyl ether of bisphenol-A type epoxy were investigated by Fourier transform infrared spectroscopy (FTIR). The presence of the amine group perturbs the alternating copolymerization of the anhydride and epoxy groups by initiating and catalyzing the reaction. Hydrolysis also promoted the reaction rate. Samples containing ETS cured more rapidly than those containing BTS at the same composition. Imide formation was not significant in the presence of the alkyl-ended silanes. A very simple mathematical simulation was invoked to justify assumptions made during data analysis.
Insurance agent contact system
US Patent & Trademark Office Database
An online insurance information system comprises an insurance quoting system, an agent contact system, agent systems, and customer systems. The agent contact system comprises a customer interfacing subsystem, a create contact engine, an agent interfacing subsystem, and a process contact engine. The customer interfacing subsystem is coupled to the quoting system and to a given one of the customer systems for receiving an online indication by a given customer of a desire to pursue a policy with a given agent. The given customer comprises a given contact. The create contact engine identifies the given agent system and saves in a database local to the agent contact system a personal insurance profile and contact information corresponding to the given customer. The agent interfacing subsystem coupled to the given agent system receives an online indication by the given agent of a desire to view, print, or modify the contact information. The process contact engine contacts the given agent system with information regarding the given contact, and accesses and modifies the contact information in accordance with online indications made by the agent.
Application of high performance liquid chromatography coupled to on-line solid-phase extraction-nuclear magnetic resonance spectroscopy for the analysis of degradation products of V-class nerve agents and nitrogen mustard
The detection and identification of the degradation products of nitrogen mustard and nerve agent VX by high performance liquid chromatography coupled to on-line solid-phase extraction-nuclear magnetic resonance spectroscopy (HPLC-UV-SPE-NMR) were demonstrated. The analytes selected for the study were N,N-dimethylaminoethanol (DMAE), N,N-diethylaminoethanol (DEAE), N,N-diisopropylaminoethanol (DIAE) and triethanolamine (TEA). Offline solid-phase extraction (SPE) followed by derivatization was applied to eliminate the interferents
Avik Mazumder; Ajeet Kumar; Ajay K. Purohit; Devendra K. Dubey
The Effects of Short Glass Fibre (SGF) Loading and a Silane Coupling Agent on Properties of Polypropylene\\/Waste Tyre Dust\\/Short Glass Fibre (PP\\/WTD\\/SGF) Composites
The properties of polypropylene\\/waste tyre dust\\/short glass fibre (PP\\/WTD\\/SGF) composites at 0 to 20�php SGF loading, with and without a silane coupling agent, ?-aminopropyltrimethoxysilane (?-APS) were studied. The results reveal that the equilibrium torque and Young's modulus increased while tensile strength and elongation at break decreased as SGF loading increased. SEM micrographs show poor adhesion of SGF-PP\\/WTD while FTIR analysis
Z. Zainal; H. Ismail
Efficacy of reducing agent and surfactant contacting pattern on the performance characteristics of nickel electroless plating baths coupled with and without ultrasound.
This article addresses furthering the role of sonication for the optimal fabrication of nickel ceramic composite membranes using electroless plating. Deliberating upon process modifications for surfactant induced electroless plating (SIEP) and combined surfactant and sonication induced electroless plating (SSOEP), this article highlights a novel method of contacting of the reducing agent and surfactant to the conventional electroless nickel plating baths. Rigorous experimental investigations indicated that the combination of ultrasound (in degas mode), surfactant and reducing agent pattern had a profound influence in altering the combinatorial plating characteristics. For comparison purpose, purely surfactant induced nickel ELP baths have also been investigated. These novel insights consolidate newer research horizons for the role of ultrasound to achieve dense metal ceramic composite membranes in a shorter span of total plating time. Surface and physical characterizations were carried out using BET, FTIR, XRD, FESEM and nitrogen permeation experiments. It has been analyzed that the SSOEP baths provided maximum ratio of percent pore densification per unit metal film thickness (PPD?) and hold the key for further fine tuning of the associated degrees of freedom. On the other hand SIEP baths provided lower (PPD?) ratio but higher PPD. For SSOEP baths with dropwise reducing agent and bulk surfactant, the PPD and metal film thickness values were 73.4% and 8.4 ?m which varied to 66.9% and 13.3 ?m for dropwise reducing agent and drop surfactant case. PMID:24480601
Agarwal, Amrita; Pujari, Murali; Uppaluri, Ramgopal; Verma, Anil
Stereospecific Nickel-Catalyzed Cross-Coupling Reactions of Alkyl Grignard Reagents and Identification of Selective Anti-Breast Cancer Agents**
?-Hydrogen-containing alkyl Grignard reagents were used in a stereospecific nickel-catalyzed cross-coupling reaction to form sp3�sp3 carbon�carbon bonds. Aryl Grignard reagents were also utilized to synthesize 1,1-diarylalkanes. Several compounds synthesized by this method exhibited selective inhibition of proliferation of MCF-7 breast cancer cells.
Osborne, Charlotte A.; Moore, Curtis E.; Morrissette, Naomi S.; Jarvo, Elizabeth R.
Comparative studies of the preparation of immunoliposomes with the use of two bifunctional coupling agents and investigation of in vitro immunoliposome-target cell binding by cytofluorometry and electron microscopy.
The two coupling agents SPDP (N-succinimidyl-3-(2-pyridyldithio)propionate) and SATA (N-succinimidyl-S-acetylthioacetate) were compared in their efficiency and feasibility to couple monoclonal antibodies (Abs) via thioether linkage to liposomes functionalized by various lipophilic maleimide compounds like N-(3-maleimidopropionyl)-N2-palmitoyl-L-lysine methyl ester (MP-PL), N-(3-maleimidopropionyl)phosphatidylethanolamide (MP-PE), N6-(6-maleimidocaproyl)-N2-palmitoyl-L-lysine methyl ester (EMC-PL), and N-(6-maleimidocaproyl)phosphatidylethanolamine (EMC-PE). The composition of the liposomes was soy phosphatidylcholine (SPC), cholesterol, maleimide compounds and alpha-tocopherol (1:0.2:0.02:0.01, mol parts), plus N4-oleylcytosine arabinoside (NOAC) as cytostatic prodrug (0.2 mol parts) and a new, lipophilic and highly fluorescent dye N,N'-bis(1-hexylhfetyl)-3,4:9,10-perylenebis(dicarboximid ) (BHPD, 0.006 mol parts). From the maleimide derivatives MP-PL was the most effective in terms of preservation of the coupling activity in dependence of liposome storage. The coupling of the monoclonal A B8-24.3 (mouse IgG2b, MHC class I, anti H-2kb) and IB16-6 (rat IgG2a, anti B16 mouse melanoma) to the drug carrying liposomes was more effective and easier to accomplish with SATA as compared to SPDP. Coupling rates of 60-65% were obtained with SATA at molar ratios of 12 SATA:1 Ab:40 maleimide spacer groups on the surface of one liposome. The highest coupling rates with SPDP were obtained at the ratio of 24 SPDP:1 Ab:40 liposomal maleimide groups, with an Ab binding efficiency of only 20-25%. The optimal in vitro binding conditions to specific target cells (EL4 for B8-24.3-liposomes and B16-F10 for IB16-6-liposomes) were determined by cytofluorometric measurement of the liposomal BHPD fluorescence with SATA linked Abs. Optimal immunoliposome binding to specific epitopes on the target cells was achieved with 1-2 Ab molecules coupled to one liposome, with immunoliposome concentrations of 20-130 nM and with a small incubation volume of 0.3-0.4 ml. The specificity of the binding of B8-24.3-liposomes to EL4 target cells was visualized by scanning electron microscopy. Antibody mediated endocytic uptake of immunoliposomes could be demonstrated by transmission electron microscopy. PMID:2378882
Schwendener, R A; Tr�b, T; Schott, H; Langhals, H; Barth, R F; Groscurth, P; Hengartner, H
Transport of the photodynamic therapy agent 5-aminolevulinic acid by distinct H+-coupled nutrient carriers coexpressed in the small intestine.
5-Aminolevulinic acid (ALA) is a prodrug used in photodynamic therapy, fluorescent diagnosis, and fluorescent-guided resection because it leads to accumulation of the photosensitizer protoporphyrin IX (PpIX) in tumor tissues. ALA has good oral bioavailability, but high oral doses are required to obtain selective PpIX accumulation in colonic tumors because accumulation is also observed in normal gut mucosa. Structural similarities between ALA and GABA led us to test the hypothesis that the H(+)-coupled amino acid transporter PAT1 (SLC36A1) will contribute to luminal ALA uptake. Radiolabel uptake and electrophysiological measurements identified PAT1-mediated H(+)-coupled ALA symport after heterologous expression in Xenopus oocytes. The selectivity of the nontransported inhibitors 5-hydroxytryptophan and 4-aminomethylbenzoic acid for, respectively, PAT1 and the H(+)-coupled di/tripeptide transporter PepT1 (SLC15A1) were examined. 5-Hydroxytryptophan selectively inhibited PAT1-mediated amino acid uptake across the brush-border membrane of the human intestinal (Caco-2) epithelium whereas 4-aminomethylbenzoic acid selectively inhibited PepT1-mediated dipeptide uptake. The inhibitory effects of 5-hydroxytryptophan and 4-aminomethylbenzoic acid were additive, demonstrating that both PAT1 and PepT1 contribute to intestinal transport of ALA. This is the first demonstration of overlap in substrate specificity between these distinct transporters for amino acids and dipeptides. PAT1 and PepT1 expression was monitored by reverse transcriptase-polymerase chain reaction using paired samples of normal and cancer tissue from human colon. mRNA for both transporters was detected. PepT1 mRNA was increased 2.3-fold in cancer tissues. Thus, increased PepT1 expression in colonic cancer could contribute to the increased PpIX accumulation observed. Selective inhibition of PAT1 could enhance PpIX loading in tumor tissue relative to that in normal tissue. PMID:19789362
Anderson, Catriona M H; Jevons, Mark; Thangaraju, Muthusamy; Edwards, Noel; Conlon, Nichola J; Woods, Steven; Ganapathy, Vadivel; Thwaites, David T
Biological Agents
... Statistics Training Publications Newsroom Small Business Anti-Retaliation Biological Agents Safety and Health Topics A-Z Index What's New Biological agents include bacteria, viruses, fungi, other microorganisms and ...
Pedagogical Agents on the Web
Animated pedagogical agents are lifelike animated characters that facilitate the learning process. Th is paper describes Adele, a pedagogical agent that is design ed to work with Web-based educational simulations. The Adele architecture implements key pedagogical funct ions: presentation, student monitoring and feedback , probing questions, hints, and explanations. These capabili ties are coupled with an animated persona that supp
W. Lewis Johnson; Erin Shaw; Rajaram Ganeshan
Further application of the diazotizationcoupling spectrophotometric technique to the determination of aromatic amines with 8-amino-1 -hydroxynaphthalene-3,6-disulphonic acid and N-(1-naphthyl)-ethylenediamine as coupling agents.
Twenty-two aromatic amines are determined by the diazotization-coupling spectrophotometric technique, using 8-amino-1-hydroxynaphthalene-3,6-disulphonic acid (H-acid) and N-(1-naphthyl) ethylenediamine (N-na) as coupling agents. The following are determined by both methods: 2-and 4-ethylaniline, 4-aminobenzonitrile, 3- and 4-aminoacetophenone, 4-aminobenzophenone, 4-iodoaniline, 2,5-dichloroaniline, 4-aminohippuric acid, 2-aminobenzyl alcohol, 3-aminobenzamide, sulphathiazole, 2-, 3- and 4-methoxyaniline and 2,4-, 3,4- and 3,5-dimethylaniline. It is possible to determine 2,3- and 2,5-dimethylaniline only by the H-acid method, but 2,6-dimethylaniline cannot be determined by either method. 2-Aminobenzamide can only be determined by the N-na method. In the application of the H-acid method to the methoxyanilines and dimethylanilines, the colour is developed by adding a large excess of sodium bicarbonate and H-acid. In the application of the N-na method to the ethylanilines, methoxyanilines and 2,4-, 3,4- and 3,5-dimethylanilines, the colour is developed by addition of a large excess of N-na reagent and allowing the solution to stand overnight. PMID:18963593
Water Soluble Phosphane-Gold(I) Complexes. Applications as Recyclable Catalysts in a Three-component Coupling Reaction and as Antimicrobial and Anticancer Agents
Water-soluble compounds of the type [AuCl(PR3)] with alkyl-bis-(m-sulfonated-phenyl)-(mC6H4SO3Na)2 and dialkyl-(m-sulfonated-phenyl)-(mC6H4SO3Na) (R = nBu, Cp) phosphanes have been prepared. Dialkyl-phosphane compounds generate water-soluble nanoparticles of 10-15 nm radius when dissolved in water. These air-stable complexes have been evaluated as catalysts in the synthesis of propargylamines via a three-component coupling reaction of aldehydes, amines and alkynes in water. The antimicrobial activity of the new complexes against Gram-positive and Gram-negative bacteria and yeast has been evaluated. The new compounds display moderate to high antibacterial activity. The more lipophilic compounds are also potent against fungi. Their cytotoxic properties have been analyzed in vitro utilizing human Jurkat T-cell acute lymphoblastic leukemia cells. Compounds with dialkyl-(m-sulfonated-phenyl)-(mC6H4SO3Na) phosphanes displayed moderate to high cytotoxicity on this cell line. Death cell mechanism occurs mainly by early apoptosis. The catalytic/biological activity of the previously described compound with commercial m-trisulfonated-triphenylphosphine [AuCl(TPPTS)] (6) has been also evaluated to compare the effects of the higher basicity and lipophilicity of the alkyl- and di-alkyl-(m-sulfonated-phenyl) phosphanes on these new compounds.
Elie, Benelita T.; Levine, Chaya; Ubarretxena-Belandia, Iban; Varela-Ramirez, Armando; Aguilera, Renato J.; Ovalle, Rafael; Contel, Maria
Software agents
this paper, we discuss these questions and describe someemerging technologies that provide answers. In the final section, we mention some additionalissues and summarize the key points of the paper. (For more information onagent-based software engineering, see [Genesereth 1989] and [Genesereth 1992]. See also[Shoham 1993] for a description of a variation of agent-based software engineering knownas "agent-oriented programming".)2. Agent Communication Language
Michael R. Genesereth; Steven P. Ketchpel
Analysis of Inorganic Antimicrobial Agents in Antimicrobial Products: Evaluation of a Screening Method by X-ray Fluorescence Spectrometry and the Measurement of Metals by Inductively Coupled Plasma Atomic Emission Spectroscopy
Antimicrobial agents used in antimicrobial products are classified into inorganic, organic, and natural organic compounds. Inorganic agents, such as Cu, Zn, and Ag compounds, are known to be relatively safe, and these agents are used in many kinds of products. Patients with metal allergy and infants should avoid coming in contact with products in which inorganic agents are used at
Harunobu Nakashima; Tomoko Ooshima
Application of high performance liquid chromatography coupled to on-line solid-phase extraction-nuclear magnetic resonance spectroscopy for the analysis of degradation products of V-class nerve agents and nitrogen mustard.
The detection and identification of the degradation products of nitrogen mustard and nerve agent VX by high performance liquid chromatography coupled to on-line solid-phase extraction-nuclear magnetic resonance spectroscopy (HPLC-UV-SPE-NMR) were demonstrated. The analytes selected for the study were N,N-dimethylaminoethanol (DMAE), N,N-diethylaminoethanol (DEAE), N,N-diisopropylaminoethanol (DIAE) and triethanolamine (TEA). Offline solid-phase extraction (SPE) followed by derivatization was applied to eliminate the interferents and make the analytes amenable for UV detection. Thereafter, chromatographically separated derivatives were trapped on on-line SPE cartridges. They were subsequently eluted and 1H NMR and COSY spectra were obtained. The overall detection limits of the LC-UV-SPE-NMR method for the mentioned analytes were found to be 18, 23, 25, and 32 mg/L respectively. Applicability of the method to real samples was demonstrated by the analysis of samples provided during the 22nd OPCW official proficiency test. The method gave reproducible NMR spectra devoid of intense background signals. PMID:20303089
Mazumder, Avik; Kumar, Ajeet; Purohit, Ajay K; Dubey, Devendra K
Radioprotective Agents.
Lists 73 domestic and foreign references on radioprotective (anti-radiation) agents added to the CFSTI collection during the period February 1963 through April 1965. Includes reports on protective effects of natural foods and chemicals i. e. 2-mercaptoeth...
[Antitubulin agents].
Microtubules are dynamic filamentous cytoskeletal proteins that are an important therapeutic target in patients with tumors. Microtubule binding agents have been part of the pharmacopoeia of cancer for decades, and until the advent of targeted therapy microtubules represented the only alternative to DNA as a therapeutic target in cancer. There are currently a variety of available vinca alkaloids and taxanes and other agents, such as ixabepilone and eribulin, have also been approved. Maytansinoids have been used for the production of immunoconjugates, monoclonal antibodies covalently bound to antimitotic molecules. The screening of a variety of botanical species and marine organisms continues to yield promising new antitubulin agents with novel properties. Enhanced tumor specificity, reduced neurotoxicity, and insensitivity to chemoresistance mechanisms are the three main objectives in the current search for novel microtubule binding agents. PMID:22023745
Dumontet, Charles
Dynamic Agents of Magnetosphere-Ionosphere Coupling
NASA Technical Reports Server (NTRS)
VISIONS sounding rocket mission (VISualizing Ion Outflow via Neutral atom imaging during a Substorm) has been awarded to NASA/GSFC (PI Rowland) in order to provide the first combined remote sensing and in situ measurements of the regions where ion acceleration to above 5 e V is occurring, and of the sources of free energy and acceleration mechanisms that accelerate the ions. The key science question of VISIONS is how, when, and where, are ions accelerated to escape velocities in the auroral zone below 1000 km, following substorm onset? Sources of free energy that power this ion acceleration process include (but not limited) electron precipitation, field-aligned currents, velocity shears, and Alfvenic Poynting flux. The combine effect of all these processes on ionospheric ion outflows will be investigated in a framework of the kinetic model that has been developed by Khazanov et al. in order to study the polar wind transport in the presence of photoelectrons.
Khazanov, George V.; Rowland, Douglas E.; Moore, Thomas E.; Collier, Michael
Sunscreening Agents
The increasing incidence of skin cancers and photodamaging effects caused by ultraviolet radiation has increased the use of sunscreening agents, which have shown beneficial effects in reducing the symptoms and reoccurrence of these problems. Many sunscreen compounds are in use, but their safety and efficacy are still in question. Efficacy is measured through indices, such as sun protection factor, persistent pigment darkening protection factor, and COLIPA guidelines. The United States Food and Drug Administration and European Union have incorporated changes in their guidelines to help consumers select products based on their sun protection factor and protection against ultraviolet radiation, whereas the Indian regulatory agency has not yet issued any special guidance on sunscreening agents, as they are classified under cosmetics. In this article, the authors discuss the pharmacological actions of sunscreening agents as well as the available formulations, their benefits, possible health hazards, safety, challenges, and proper application technique. New technologies and scope for the development of sunscreening agents are also discussed as well as the role of the physician in patient education about the use of these agents.
Martis, Jacintha; Shobha, V; Sham Shinde, Rutuja; Bangera, Sudhakar; Krishnankutty, Binny; Bellary, Shantala; Varughese, Sunoj; Rao, Prabhakar; Naveen Kumar, B.R.
Given the emergence of new and varied energy producers, consumers, and combinations thereof, software processes and services that work on our behalf must adopt the qualities of intelligent distributed systems to address challenges including: local control of processes, local ownership of data, loose coupling and late binding, authentication and non-repudiation, balancing of competition and cooperation, and graceful degradation. Rational agents
Apperson Johnson
Agent Exoplanet
NSDL National Science Digital Library
Astronomers at Las Cumbres Observatory are investigating exoplanets - planets which orbit stars other than our Sun - and you can too. Joining Agent Exoplanet you will study known exoplanets using images taken by LCOGT�s telescopes. You'll measure the brightness of a star while a planet moves between it and our viewpoint. You can examine as many images, from as many exoplanet transit events, as you like and contribute to understanding the properties of each exoplanet.
Network, Las C.
Media agent
Systems and methods for a media agent are described. In one aspect, user access of a media content source is detected. Responsive to this detection, a piece of media content and associated text is collected from the media content source. Semantic text features are extracted from the associated text and the piece of media content. The semantic text features are indexed into a media database.
Addressing Mobile Agent Security through Agent Collaboration
The use of agent paradigm in today's applications is hampered by the security concerns of agents and hosts alike. The agents require the presence of a secure and trusted execution environment; while hosts aim at preventing the execution of potentially malicious code. In general, hosts support the migration of agents through the provision of an agent server and managing the
Evens Jean; Yu Jiao; Ali-R. Hurson
Operational Semantics for Agents by Iterated Refinement
In this paper we evaluate transition systems as a tool for providing a rule-based specification of the operational aspects of au- tonomous agents. By our technique, different aspects of an agent can be analyzed and designed in a loosely coupled way, enabling the possibility of studying their properties in isolation. We take as a use case the ParADE framework for
Federico Bergenti; Giovanni Rimassa; Mirko Viroli
KGB agents
A short story is reported in which the activity of Communist Party of the USSR and secret KGB agents, which were payed by the State, in view of controlling of the conscience of population. The story reffers to the Physics Department of the Moscow University, Planing Institute of the Gosplan of Moldavian S.S.R. and Chishinau Technical University (actually: Technical University of Moldova), where the author has worked during Soviet times. Almost every 6-th citizen in the USSR was engaged in this activity, while actually the former communists rule in the Republic of Moldova.
Gaina, Alex
[Antiplatelet agents].
Atherothrombosis is a major global public health problem. Chronic atherosclerotic disease is often clinically silent and coexists across multiple vascular beds but, when complicated by thrombosis, it can result in an acute coronary syndrome, stroke, transient ischemic attack, and critical limb ischemia. Platelets play a role in the development of chronic atherosclerotic disease and are a key mediator of clinical events in atherothrombosis. Numerous clinical trials have tested antiplatelet agents for primary and secondary prevention, and several new antiplatelet drugs are under development. There is evidence of clear benefit of single and, in some cases, dual antiplatelet therapy in the prevention of recurrent cardiovascular and cerebrovascular complications. Dual antiplatelet therapy has emerged as the standard of care for acute coronary syndromes, with aspirin typically being used in combination with clopidogrel or one of the newer more potent ADP receptor antagonists (ticagrelor or prasugrel). Conversely, in chronic stable coronary disease, no benefit of dual antiplatelet therapy has yet been convincingly demonstrated Evidence supporting routine use of aspirin or any other antiplatelet agent for primary prevention is mixed, and this strategy should only be considered for individual high-risk patients in whom the thrombotic risk outweighs the risk of major bleeding complications. PMID:24919367
Steg, Gabriel
The Agent Pattern for Mobile Agent Systems
This paper presents the Agent pattern, a design pa ttern u seful t o d evelop d ynamic and distributed app lications. The Agent pattern p rovides a clean and easy way to d evelop agent-based applications, mainly in open and large-scale distributed environments such as the Internet and application areas such as Electronic Commerce. The Agent pattern encapsulates a
Alberto Silva; Jos� Delgado
Detecting agents.
This paper reviews a recent set of behavioural studies that examine the scope and nature of the representational system underlying theory-of-mind development. Studies with typically developing infants, adults and children with autism all converge on the claim that there is a specialized input system that uses not only morphological cues, but also behavioural cues to categorize novel objects as agents. Evidence is reviewed in which 12- to 15-month-old infants treat certain non-human objects as if they have perceptual/attentional abilities, communicative abilities and goal-directed behaviour. They will follow the attentional orientation of an amorphously shaped novel object if it interacts contingently with them or with another person. They also seem to use a novel object's environmentally directed behaviour to determine its perceptual/attentional orientation and object-oriented goals. Results from adults and children with autism are strikingly similar, despite adults' contradictory beliefs about the objects in question and the failure of children with autism to ultimately develop more advanced theory-of-mind reasoning. The implications for a general theory-of-mind development are discussed.
Johnson, Susan C
Agent-based resource discovery architecture for environmental emergency management
An agent-based environmental emergency management framework is introduced as a loosely coupled collection of agents that can cooperate to prepare for and response to environmental emergency situations. In this framework, resources play a critical role because they are the foundation for taking action in environmental emergencies. Therefore, an agent-based resource discovery architecture is then proposed to search for the relevant
Kevin F. R. Liu
Mobile Agents White Paper
this paper.IntroductionNew productsNew applicationsNew networksAbout "Mobile Agents"Enabling mobile agentsMobile agent paradigmMobile agent conceptsMobile agent technologyProgramming mobile agentsProgramming a placeProgramming an agentUsing mobile agentsMonitoring changing conditionsDoing time-consuming legworkUsing services in combinationThe user experienceHow agents provide the experienceVariations on the themeAcknowledgmentsRelated workReferencesIntroduction
Jim White
Pinning synchronization of a mobile agent network
We investigate the problem of controlling a group of mobile agents in a plane in order to move them towards a desired orbit via pinning control, in which each agent is associated with a chaotic oscillator coupled with those of neighboring agents, and the pinning strategy is to have the common linear feedback acting on a small fraction of agents by random selection. We explore the effects of the pinning probability, feedback gains and agent density in the pinning synchronization of a mobile agent network under a fast-switching constraint, and perform numerical simulations for validation. In particular, we show that there exists a critical pinning density for network synchronization with an unbounded region: above the threshold, the dynamical network can be controlled by pinning; below it, anarchy prevails. And for the network with a single bounded synchronization region, pinning control has little effect as regards enhancing network synchronizability.
Wang, Lei; Sun, You-xian
Mobile agent security
The agent paradigm is currently attracting much research. A mobile agent is a particular type of agent with the ability to migrate from one host to another where it can resume its execution. In this article we consider security issues that need to be addressed before multi-agent systems in general, and mobile agents in particular, can be a viable solution
Niklas Borselius
Preparing Change Agents for Change Agent Roles.
ERIC Educational Resources Information Center
Seventy-seven Spanish- and Portuguese-speaking agricultural change agents from developing Central and South American countries responded to a questionnaire which sought perceptions of the roles in which the change agents felt they were involved and the roles for which they felt they were being trained. The agents were participating in training�
Sedlacek, James R.
Remote Agent Demonstration
We describe the computer demonstration of the Remote Agent Experiment (RAX). The Remote Agent is a high-level, model-based, autonomous control agent being validated on the NASA Deep Space 1 spacecraft.
Dorais, Gregory A.; Kurien, James; Rajan, Kanna
Change agents, double agents, secret agents: EEO in New Zealand
Purpose � This paper theorises how equal employment opportunities (EEO) practitioners (EPs) operate as change agents within organisations. Design\\/methodology\\/approach � It takes a feminist and post-structuralist perspective, in which EPs are seen as agents of positive social change, contesting existing discourses, but are also themselves subject to being changed by their engagement in those same discursive formations. The key example
Deborah Jones
Software agents: an overview
Agent software is a rapidly developing area of research. However, the overuse of the word 'agent' has tended to mask the fact that, in reality, there is a truly heterogeneous body of research being carried out under this banner. This overview paper presents a typology of agents. Next, it places agents in context, defines them and then goes on, inter
Hyacinth S. Nwana
Total Synthesis of Bryostatin 16 using a Pd-Catalyzed Diyne-Coupling as Macrocyclization Method and Synthesis of C20-epi-Bryostatin 7 as a Potent Anticancer Agent
Asymmetric total synthesis of bryostatin 16 was achieved in 26 steps in the longest linear sequence/39 total steps from aldehyde 10. A Pd-catalyzed alkyne-alkyne coupling was employed for the first-time as a macrocyclization method in a natural product synthesis. A route to convert bryostatin 16 to a new family of bryostatin analogues was developed. Toward the end, 20-epi-bryostatin 7, was synthesized from a bryostatin 16-like intermediate; and the key step involves a Re-catalyzed epoxidation/ring-opening reaction. Preliminary biological studies indicated that this new analogue exhibits nanomolar anti-cancer activity against several cancer cell lines.
Trost, Barry M.; Dong, Guangbin
Asymmetrically Coupled Directed Percolation Systems
We introduce a dynamical model of coupled directed percolation systems with two particle species. The two species A and B are coupled asymmetrically in that A particles branch B particles, whereas B particles prey on A particles. This model may describe epidemic spreading controlled by reactive immunization agents. We study nonequilibrium phase transitions with attention focused on the multicritical point where both species undergo the absorbing phase transition simultaneously. In one dimension, we find that the inhibitory coupling from B to A is irrelevant and the model belongs to the unidirectionally coupled directed percolation class. On the contrary, a mean-field analysis predicts that the inhibitory coupling is relevant and a new universality appears with a variable dynamic exponent. Numerical simulations on small-world networks confirm our predictions.
Noh, Jae Dong; Park, Hyunggyu
Chemical warfare agents.
Chemical warfare agents are compounds of different chemical structures. Simple molecules such as chlorine as well as complex structures such as ricin belong to this group. Nerve agents, vesicants, incapacitating agents, blood agents, lung-damaging agents, riot-control agents and several toxins are among chemical warfare agents. Although the use of these compounds is strictly prohibited, the possible misuse by terrorist groups is a reality nowadays. Owing to this fact, knowledge of the basic properties of these substances is of a high importance. This chapter briefly introduces the separate groups of chemical warfare agents together with their members and the potential therapy that should be applied in case someone is intoxicated by these agents. PMID:20358695
Kuca, Kamil; Pohanka, Miroslav
Mobile Agents and Java Mobile Agents Toolkits
This paper gives an overview of what mobile agents are, what they should do, and how they can be implemented in Java. Why Java? The choice to concentrate on Java is evoked by many existing solutions in Java that handles architectural heterogeneity between communicating machines on the net. It seems to be the best available language for making mobile agents
Damir Horvat; Dragana Cvetkovic; Veljko M. Milutinovic; P. Kocovic; V. Kovacevic
Radiographic scanning agent
A composition and method for the preparation of a technetium-99m -based scanning agent are disclosed. The scanning agent is prepared from /sup 99m/Tc, in a +3, +4 and/or +5 oxidation state, and a methanehydroxydiphosphonate bone-seeking agent which carries the radionuclide to bone mineral. The methanehydroxydiphosphonate agent provides scan sharpness equivalent or superior to commercial scanning agents, and is superior for detecting myocardial infarcts, as compared with commercial scanning agents such as ethane-1-hydroxy-1,1-diphosphonate and methanediphosphonate.
Bevan, J.A.
A composition and method for the preparation of a technetium-99m-based scanning agent are disclosed. The scanning agent is prepared from /SUP 99m/ Tc, in a +3, +4 and/or +5 oxidation state, and a methanehydroxydiphosphonate bone-seeking agent which carries the radionuclide to bone mineral. The methanehydroxydiphosphonate agent provides scan sharpness equivalent or superior to commercial scanning agents, and is superior for detecting myocardial infarcts, as compared with commercial scanning agents such as ethane-1-hydroxy-1,1-diphosphonate and methanediphosphonate.
Optical coupling
This paper describes contributions to the CMBpol Technology Study Workshop concerning optical coupling structures. These are structures in or near the focal plane which convert the free space wave to a superconducting microstrip on a SI wafer, or to the waveguide input to a HEMT receiver. In addition to an introduction and conclusions by the editor, this paper includes independent contributions by Bock on 'Planar Antenna-Coupled Bolometers for CMB Polarimetry', by Gunderson and Wollack on 'Millimeter-Wave Platlet Feeds', and by Lee on 'Multi-band Dual-Polarization Lens-coupled Planar Antennas for Bolometric CMB polarimetry.'
Bock, J. J.; Gundersen, J.; Lee, A. T.; Richards, P. L.; Wollack, E.
Chemical warfare agents (CWA's) are defined as any chemical substance whose toxic properties are utilised to kill, injure or incapacitate an enemy in warfare and associated military operations. Chemical agents have been used in war since times immemorial, but their use reached a peak during World War I. During World War II only the Germans used them in the infamous gas chambers. Since then these have been intermittently used both in war and acts of terrorisms. Many countries have stockpiles of these agents. There has been a legislative effort worldwide to ban the use of CWA's under the chemical weapons convention which came into force in 1997. However the manufacture of these agents cannot be completely prohibited as some of them have potential industrial uses. Moreover despite the remedial measures taken so far and worldwide condemnation, the ease of manufacturing these agents and effectiveness during combat or small scale terrorist operations still make them a powerful weapon to reckon with. These agents are classified according to mechanism of toxicity in humans into blister agents, nerve agents, asphyxiants, choking agents and incapacitating/behavior altering agents. Some of these agents can be as devastating as a nuclear bomb. In addition to immediate injuries caused by chemical agents, some of them are associated with long term morbidities and psychological problems. In this review we will discuss briefly about the historical background, properties, manufacture techniques and industrial uses, mechanism of toxicity, clinical features of exposure and pharmacological management of casualties caused by chemical agents. PMID:21783898
Chauhan, S; Chauhan, S; D'Cruz, R; Faruqi, S; Singh, K K; Varma, S; Singh, M; Karthik, V
Synchronization of mobile chaotic agents on connected networks
This work studies the synchronization of a number of mobile agents on a substrate network. Each agent carries a chaotic map and randomly walks on a connected network. The collection of agents consists of another time-varying network derived from the substrate network. It is found that the synchronization conditions of this agent network depend on the average degree of the substrate network�s connectivity, the coupling strength between interacting agents, and the agent density in the network. Synchronization of the agent network on scale-free and ER networks is considered here, and it is found that the scale-free topology is more applicable to synchronize mobile chaotic agents. To get analytical insights, the star graph is taken and considered as a substrate network.
Bu, Shou-Liang; Wen, Jian-Ping; Zhong, Qing-Hu; Yi, Xue-Hua
Collaborative Interface Agents
Interface agents are semi-intelligent systemswhich assist users with daily computer-basedtasks. Recently, various researchers have proposeda learning approach towards building suchagents and some working prototypes have beendemonstrated. Such agents learn by `watchingover the shoulder\\
Yezdi Lashkari; Max Metral; Pattie Maes
Biological warfare agents
\\u000a Biological warfare agents are a group of pathogens and toxins of biological origin that can be potentially misused for military\\u000a or criminal purposes. The present review attempts to summarize necessary knowledge about biological warfare agents. The historical\\u000a aspects, examples of applications of these agents such as anthrax letters, biological weapons impact, a summary of biological\\u000a warfare agents and epidemiology of
Miroslav Pohanka; Kamil Ku?a
Agent-Based Computing
This article is an introductory survey of agent-based computing. The article begins with an overview of micro-level issues in agent-based systems: issues related to the design and con- struction of individual intelligent agents. The article th en goes on to discuss some macro- level issues: issues related to the design and construction of agent societies. Finally, the key application areas
Agent Oriented Programming
Shoham, Y., Agent-oriented programming, Artificial Intelligence 60 (1993) 51-92. A new computational framework is presented, called agent-oriented programming (AOP), which can be viewed as a specialization of object-oriented programming. The state of an agent consists of components such as beliefs, decisions, capabilities, and obligations; for this reason the state of an agent is called its mental state. The mental state
Yoav Shoham
Mobile Agent Organizations
Mobile agents are a u seful paradigm - other than a useful t echnology - for the development of complex Internet applications. However, the effective development of mobile agent applications r equires s uitable models and infrastructures. This paper proposes an organizational approach to the high-level design o f mobile agent applications. The idea is to models the Internet as
Giacomo Cabri; Letizia Leonardi; Marco Mamei; Franco Zambonelli
Mobile Agents Applications.
Discussion of the need to filter and retrieval relevant information from the Internet focuses on the use of mobile agents, specific software components which are based on distributed artificial intelligence and integrated systems. Surveys agent technology and discusses the agent building package used to develop two applications using IBM's Aglet�
Martins, Rosane Maria; Chaves, Magali Ribeiro; Pirmez, Luci; Rust da Costa Carmo, Luiz Fernando
Mobile Agent Security.
Mobile agent technology offers a new computing paradigm in which a program, in the form of a software agent, can suspend its execution on a host computer, transfer itself to another agent-enabled host on the network, and resume execution on the new host. ...
W. Jansen T. Karygiannis
Mobile agent technology offers a new computing paradigm in which a software agent can suspend its execution on a host computer, transfer itself to another agent-enabled host on the network, and resume execution on the new host. The use of mobile code has a long history dating back to the use of remote job entry systems in the 1960's. Today's
W. A. Jansen
Intelligent Agents: A Primer.
Provides an in-depth introduction to the various technologies that are bringing intelligent agents into the forefront of information technology, explaining how such agents work, the standards involved, and how agent-based applications can be developed. (Author/AEF)
Yu, Edmund; Feldman, Susan
Robust Agent Communities
We believe that intelligent information agents will represent their users interest in electronic marketplaces and other forums to trade, exchange, share, identify, and locate goods and services. Such informa- tion worlds will present unforeseen opportunities as well as challenges that can be best addressed by robust, self-sustaining agent communi- ties. An agent community is a stable, adaptive group of self-interested
Sandip Sen; Sabyasachi Saha; St�phane Airiau; Teddy Candale; Dipyaman Banerjee; Doran Chakraborty; Partha Mukherjee; Anil Gursel
Parallelism in Mobile Agent Network
The paper deals with parallel mobile agents and related performance evaluation framework. A model called mobile agent network is proposed. It includes a multi-agent system consisting of co-operating and communicating mobile agents, a set of processing nodes in which the agents perform services and a network that connects processing nodes and allows agent mobility. Parallelism in mobile agent network is
Vjekoslav Sinkovic; Ignac Lovrek; Mario Kusek
Transmissible encephalopathy agents
Transmissible spongiform encephalopathies (TSEs) are caused by infectious agents with stable virulence characteristics that are not encoded by the host. Agent-specific features of virulence include disease latency and tissue pathology in a given host, as well as the ability to spread to many species. Such cross-species infections contradict predictions based on the prion hypothesis. Recent transmissions of several human agents to normal mice, and to monotypic neural cells in culture, underscore the existence of unique agent clades that are prevalent in particular geographic regions. Examples include the epidemic UK bovine agent (BSE) and the New Guinea kuru agent. The virus-like biology of unique TSE agents, including epidemic spread, mutation and superinfection, can be used to systematically define features of virulence that distinguish common endemic from newly emerging strains.
Prosthesis coupling
A coupling for use in an apparatus for connecting a prosthesis to the bone of a stump of an amputated limb is described which permits a bio-compatible carbon sleeve forming a part of the prosthesis connector to float so as to prevent disturbing the skin seal around the carbon sleeve. The coupling includes a flexible member interposed between a socket that is inserted within an intermedullary cavity of the bone and the sleeve. A lock pin is carried by the prosthesis and has a stem portion which is adapted to be coaxially disposed and slideably within the tubular female socket for securing the prosthesis to the stump. The skin around the percutaneous carbon sleeve is able to move as a result of the flexing coupling so as to reduce stresses caused by changes in the stump shape and/or movement between the bone and the flesh portion of the stump.
Reswick, J. B.; Mooney, V.; Bright, C. W.; Owens, L. J. (inventors)
Multi-agent autonomous system
A multi-agent autonomous system for exploration of hazardous or inaccessible locations. The multi-agent autonomous system includes simple surface-based agents or craft controlled by an airborne tracking and command system. The airborne tracking and command system includes an instrument suite used to image an operational area and any craft deployed within the operational area. The image data is used to identify the craft, targets for exploration, and obstacles in the operational area. The tracking and command system determines paths for the surface-based craft using the identified targets and obstacles and commands the craft using simple movement commands to move through the operational area to the targets while avoiding the obstacles. Each craft includes its own instrument suite to collect information about the operational area that is transmitted back to the tracking and command system. The tracking and command system may be further coupled to a satellite system to provide additional image information about the operational area and provide operational and location commands to the tracking and command system.
Fink, Wolfgang (Inventor); Dohm, James (Inventor); Tarbell, Mark A. (Inventor)
Agent Architectures for Compliance
A Normative Multi-Agent System consists of autonomous agents who must comply with social norms. Different kinds of norms make different assumptions about the cognitive architecture of the agents. For example, a principle-based norm assumes that agents can reflect upon the consequences of their actions; a rule-based formulation only assumes that agents can avoid violations. In this paper we present several cognitive agent architectures for self-monitoring and compliance. We show how different assumptions about the cognitive architecture lead to different information needs when assessing compliance. The approach is validated with a case study of horizontal monitoring, an approach to corporate tax auditing recently introduced by the Dutch Customs and Tax Authority.
Burgemeestre, Brigitte; Hulstijn, Joris; Tan, Yao-Hua
DCTD � Featured Agents
The �Featured Agents� portion of the DCTD Website provides information for researchers involved in drug discovery and development. Any public preclinical and clinical data that DCTD has on a particular agent are presented here. New agents will be added periodically to the current list. DCTD Website visitors may subscribe to the Listserv on this page to be notified when additions to the list are made.
Evaluating dentin bonding agents: an update.
Technological and material advancements in contemporary adhesive protocols have resulted in the development of several generations of bonding agents. Acid-etching procedures coupled with restorative materials that demonstrate improved aesthetics, bond strength, and durability have led to increased interest in the use of multi-component, single-component, and self-etching adhesives for everyday protocols. Micromechanical retention has significantly evolved into a more predictable science through the incorporation of various dentin bonding agents. This article reviews current literature and discusses current concepts on routine adhesion during placement of indirectly fabricated restorations. PMID:14509094
Ahmad, Irfan
Practical agents help out [virtual agent system
Artificial intelligence probes further into making machines more like humans. Researchers are using technology advances in speech recognition, conversational interactions, decision-making, natural language AI, enhanced data-mining techniques, and emotion to create virtual practical agents. These text, voice, and graphical avatars assist people with various tasks and difficult situations. They can help people better use services, make financial transactions, learn about
D. Voth
This paper gives an overview of what the mobile agents are, what they should do and how they can be implemented in Java. Why Java? The choice to concentrate on Java is evoked by many existing solutions in Java that handles architectural heterogeneity between communicating machines on the net. It seems to be the best available language for making mobile
Damir Horvat; Dragana Cvetkovi?; Veljko Milutinovi?; Petar Ko?ovi?; Vlada Kova?evi?
Joint chemical agent detector (JCAD): the future of chemical agent detection
The Joint Chemical Agent Detector (JCAD) has continued development through 2002. The JCAD has completed Contractor Validation Testing (CVT) that included chemical warfare agent testing, environmental testing, electromagnetic interferent testing, and platform integration validation. The JCAD provides state of the art chemical warfare agent detection capability to military and homeland security operators. Intelligence sources estimate that over twenty countries have active chemical weapons programs. The spread of weapons of mass destruction (and the industrial capability for manufacture of these weapons) to third world nations and terrorist organizations has greatly increased the chemical agent threat to U.S. interests. Coupled with the potential for U.S. involvement in localized conflicts in an operational or support capacity, increases the probability that the military Joint Services may encounter chemical agents anywhere in the world. The JCAD is a small (45 in3), lightweight (2 lb.) chemical agent detector for vehicle interiors, aircraft, individual personnel, shipboard, and fixed site locations. The system provides a common detection component across multi-service platforms. This common detector system will allow the Joint Services to use the same operational and support concept for more efficient utilization of resources. The JCAD detects, identifies, quantifies, and warns of the presence of chemical agents prior to onset of miosis. Upon detection of chemical agents, the detector provides local and remote audible and visual alarms to the operators. Advance warning will provide the vehicle crew and other personnel in the local area with the time necessary to protect themselves from the lethal effects of chemical agents. The JCAD is capable of being upgraded to protect against future chemical agent threats. The JCAD provides the operator with the warning necessary to survive and fight in a chemical warfare agent threat environment.
Laljer, Charles E.
Mobile Agent Architectures.
Mobile agent technology is a new research field. The purpose of this report is to take a closer look of this new field, identify its problems, and describe its current state. The theoretical section of this report defines the three properties of agents: m...
M. Persson
Programming Satan's Agents
Abstract: Mobile agent security is still a young discipline and most naturally, the focus up to the timeof writing was on inventing new cryptographic protocols for securing various aspects ofmobile agents. However, past experience shows that protocols can be flawed, and flawsin protocols can remain unnoticed for a long period of time. The game of breaking andfixing protocols is a
Volker Roth
Evolutionary intelligent agents
Evolutionary intelligent agents (EIA) are intelligent agents provided with a genotype that controls their capabilities to carry out various tasks, i.e., their phenotype. EIA are a cognitive and genetically controlled version of ants and bees, with links to both artificial intelligence and neural networks. The evolution of the population is task dependent and favors the predominance of the individuals best
Paul CRISTEA; Aurel ARSENE; Bogdan NITULESCU
Intelligent agent workbench
An intelligent agent workbench is disclosed for developing a computer-based intelligent agent that can be inserted between a system and an individual performing a pre-defined function with the system and/or that can supplant such function performed by such individual. In the workbench, an agent author allows a workbench user to create and modify an intelligent agent in a graphical representation. The workbench also has an execution engine for executing a non-graphical representation of the agent both within the workbench and outside the workbench as a stand-alone agent, and an interpreter for automatically translating between the non-graphical and graphical representations. The agent has an instance structure representing a current problem instance, perception structures, task performance structures, and a priority structure. Each perception structure represents information perceived from the system, and includes sub-structures for obtaining information from the system and updating the instance structure therewith. Each task performance structure represents a task the agent can perform, and includes sub-structures for accessing the instance structure to obtain instance information, modifying instance information in the instance structure, and determining a priority for the task performance structure and notifying the instance structure of the determined priority.
Mobile Agent Security
Mobile agent technology is a new paradigm of distributed computing that can replace the conventional client-server model. However, it has not become popular due to some problems such as security. Threats to mobile agent security generally fall into three main classes: disclosure of information, denial of service, and corruption of information. Four threat categories are identified: threats stemming from an
Levent Ertaul; Jayalalitha Panda
How do agents represent?
Representation is inherent to the concept of an agent, but its importance in complex systems has not yet been widely recognised. In this paper I introduce Peirce's theory of signs, which facilitates a definition of representation in general. In summary, representation means that for some agent, a model is used to stand in for another entity in a way that shapes the behaviour of the agent with respect to that entity. Representation in general is then related to the theories of representation that have developed within different disciplines. I compare theories of representation from metaphysics, military theory and systems theory. Additional complications arise in explaining the special case of mental representations, which is the focus of cognitive science. I consider the dominant theory of cognition � that the brain is a representational device � as well as the sceptical anti-representational response. Finally, I argue that representation distinguishes agents from non-representational objects: agents are objects capable of representation.
Ryan, Alex
Pediatric Antifungal Agents
Purpose of review In immunocompromised hosts, invasive fungal infections are common and fatal. In the past decade, the antifungal armamentarium against invasive mycoses has expanded greatly. The purpose of this report is to review the most recent literature addressing the use of antifungal agents in children. Recent findings Most studies evaluating the safety and efficacy of antifungal agents are limited to adults. However, important progress has been made in describing the pharmacokinetics and safety of newer antifungal agents in children, including the echinocandins. Summary Dosage guidelines for newer antifungal agents are currently based on adult and limited pediatric data. Because important developmental pharmacology changes occur throughout childhood impacting the pharmacokinetics of these agents, antifungal studies specifically designed for children are necessary.
Cohen-Wolkowiez, Michael; Moran, Cassandra; Benjamin, Daniel K.; Smith, P Brian
Specific biological agent taggants
The preliminary data presented here suggests that direct coating of biological agent with DNA capture elements and organic semiconductor (DALM) with chelated rare earths such as scandium, europium or neodymium can be used to track the agent, even when the biological components have been subsequently destroyed. The use of these three taggant components in conjunction with each other affords the opportunity to determine the presence of the biological agent by several methods---laser induced plasma spectroscopy, thermochemiluminescence, mass spectroscopy, polymerase chain reaction (PCR; if the primers are left on the DCEs or the agent's own DNA is used as the source of the amplicon). The specific DCE-labeling or PCR allows for confirmation of physical measurement results as specific to the agent.
Kiel, Johnathan L.; Holwitt, Eric A.; Parker, Jill E.; Vivekananda, Jeeva; Franz, Veronica; Sloan, Mark A.; Miziolek, Andrzej W.; DeLucia, Frank C., Jr.; Munson, Chase A.; Mattley, Yvette D.
A General Methodology for Mathematical Analysis of Multi-Agent Systems
We propose a general mathematical methodology for studying the dynamics of multi- agent systems in which complex collective behavior arises out of local interactions between many simple agents. The mathematical model is composed of a system of coupled dif- ferential equations describing the macroscopic, or collective, dynamics of an agent-based system. We illustrate our approach by applying it to analyze
Kristina Lerman; Aram Galstyan
Moral actor, selfish agent.
People are motivated to behave selfishly while appearing moral. This tension gives rise to 2 divergently motivated selves. The actor-the watched self-tends to be moral; the agent-the self as executor-tends to be selfish. Three studies present direct evidence of the actor's and agent's distinct motives. To recruit the self-as-actor, we asked people to rate the importance of various goals. To recruit the self-as-agent, we asked people to describe their goals verbally. In Study 1, actors claimed their goals were equally about helping the self and others (viz., moral); agents claimed their goals were primarily about helping the self (viz., selfish). This disparity was evident in both individualist and collectivist cultures, attesting to the universality of the selfish agent. Study 2 compared actors' and agents' motives to those of people role-playing highly prosocial or selfish exemplars. In content (Study 2a) and in the impressions they made on an outside observer (Study 2b), actors' motives were similar to those of the prosocial role-players, whereas agents' motives were similar to those of the selfish role-players. Study 3 accounted for the difference between the actor and agent: Participants claimed that their agent's motives were the more realistic and that their actor's motives were the more idealistic. The selfish agent/moral actor duality may account for why implicit and explicit measures of the same construct diverge, and why feeling watched brings out the better angels of human nature. (PsycINFO Database Record (c) 2014 APA, all rights reserved). PMID:24749822
Frimer, Jeremy A; Schaefer, Nicola K; Oakes, Harrison
Tubular Coupling
A system for coupling a vascular overflow graft or cannula to a heart pump. A pump pipe outlet is provided with an external tapered surface which receives the end of a compressible connula. An annular compression ring with a tapered internal bore surface is arranged about the cannula with the tapered internal surface in a facing relationship to the external tapered surface. The angle of inclination of the tapered surfaces is converging such that the spacing between the tapered surfaces decreases from one end of the external tapered surface to the other end thereby providing a clamping action of the tapered surface on a cannula which increases as a function of the length of cannula segment between the tapered surfaces. The annular compression ring is disposed within a tubular locking nut which threadedly couples to the pump and provides a compression force for urging the annular ring onto the cannula between the tapered surfaces. The nut has a threaded connection to the pump body. The threaded coupling to the pump body provides a compression force for the annular ring. The annular ring has an annular enclosure space in which excess cannula material from the compression between the tapered surfaces to "bunch up" in the space and serve as an enlarged annular ring segment to assist holding the cannula in place. The clamped cannula provides a seamless joint connection to the pump pipe outlet where the clamping force is uniformly applied to the cannula because of self alignment of the tapered surfaces. The nut can be easily disconnected to replace the pump if necessary.
Rosenbaum, Bernard J. (Inventor)
Sealing coupling
Disclosed is a remotely operable releasable sealing coupling which provides fluid-tight joinder of upper and a lower conduit sections. Each conduit section has a concave conical sealing surface adjacent its end portion. A tubular sleeve having convex spherical ends is inserted between the conduit ends to form line contact with the concave conical end portions. An inwardly projecting lip located at one end of the sleeve cooperates with a retaining collar formed on the upper pipe end to provide swivel capture for the sleeve. The upper conduit section also includes a tapered lower end portion which engages the inside surface of the sleeve to limit misalignment of the connected conduit sections.
Pardini, John A. (Brookfield, IL) [Brookfield, IL; Brubaker, Robert C. (Naperville, IL) [Naperville, IL; Rusnak, John J. (Orland Park, IL) [Orland Park, IL
Mobile Agent security using Proxy-agents and Trusted domains
Commercial or wide-network deployment of Mobile Agent Systems is not possible without satisfying security archi- tecture. In this paper we propose architecture for secure Mobile Agent Systems, using Trusted Domains and Proxy agents. Existing approaches are based on security services at the level of an agent system, library or specific objects. Our concept uses proxy agents to enable transparent secu-
Nikola Mitrovic; Unai Arronategui Arribalzaga
The recent bioterrorist attacks using anthrax spores have emphasized the need to detect and decontaminate critical facilities in the shortest possible time. There has been a remarkable progress in the detection, protection and decontamination of biological warfare agents as many instrumentation platforms and detection methodologies are developed and commissioned. Even then the threat of biological warfare agents and their use in bioterrorist attacks still remain a leading cause of global concern. Furthermore in the past decade there have been threats due to the emerging new diseases and also the re-emergence of old diseases and development of antimicrobial resistance and spread to new geographical regions. The preparedness against these agents need complete knowledge about the disease, better research and training facilities, diagnostic facilities and improved public health system. This review on the biological warfare agents will provide information on the biological warfare agents, their mode of transmission and spread and also the detection systems available to detect them. In addition the current information on the availability of commercially available and developing technologies against biological warfare agents has also been discussed. The risk that arise due to the use of these agents in warfare or bioterrorism related scenario can be mitigated with the availability of improved detection technologies.
Thavaselvam, Duraipandian; Vijayaraghavan, Rajagopalan
Blocked isocyanates as coupling agents for cellulose-based composites
In this work, the stability of blocked isocyanates has been evaluated and the reactivity of different urethanes with the hydroxyl groups of natural cellulose fibres has been studied during the preparation of composites. The thermal dissociation of carbamate groups studied by TGA was function of the nature of the carbamate bond. According to this, the elimination of alcanol groups took
J. Giron�s; M. T. B. Pimenta; F. Vilaseca; A. J. F. de Carvalho; P. Mutj�; A. A. S. Curvelo
Novel Phenylethynyl Imide Silanes as Coupling Agents for Titanium Alloy
The durability of titanium (Ti) alloys bonded with high temperature adhesives such as polyimides has failed to attain the level of performance required for many applications. The problem to a large part is attributed to the instability of the surface treatment on the Ti substrate. Although Ti alloy adhesive specimens with surface treatments such as chromic acid anodization, Pasa-Jell, Turco, etc. have provided high initial mechanical properties, these properties have decreased as a function of aging at ambient temperature and faster, when aged at elevated temperatures or in a hot-wet environment. As part of the High Speed Civil Transport program where Ti honeycomb sandwich structure must perform for 60,000 hours at 177 C, work was directed to the development of environmentally safe, durable Ti alloy surface treatments.
Park, C.; Lowther, S. E.; Smith, J. G., Jr.; Conell, J. W.; Hergenrother, P. M.; SaintClair, T. L.
Surface modification of cellulose using silane coupling agent.
Recently there has been a growing interest in substituting traditional synthetic polymers with natural polymers for different applications. However, natural polymers such as cellulose suffer from few drawbacks. To become viable potential alternatives of synthetic polymers, cellulosic polymers must have comparable physico-chemical properties to that of synthetic polymers. So in the present work, cellulose polymer has been modified by a series of mercerization and silane functionalization to optimize the reaction conditions. Structural, thermal and morphological characterization of the cellulose has been done using FTIR, TGA and SEM, techniques. Surface modified cellulose polymers were further subjected to evaluation of their properties like swelling and chemical resistance behavior. PMID:25037424
Thakur, Manju Kumari; Gupta, Raju Kumar; Thakur, Vijay Kumar
The Interaction of Alkoxy Silane Coupling Agents with Silica Surfaces.
The interactions of gamma-aminopropyltriethoxy silane (A-1100), gamma-methacryloxtrimethoxy silane (A-174), gamma-glycidoxytrimethoxy silane (A-187), and ethyltriethoxy silane (A-15) with silica surfaces have been studied by means of infrared spectroscopy...
R. L. Kaas J. L. Kardos
Polyimide modified with metal coupling agent for adhesion application
Polyimide hybrid metal oxide thin films used on flexible print circuit boards are prepared by the in situ sol�gel process. The precursor, poly (amic acid), containing 2,2?-bis[4-(4-aminophenoxy) phenyl]propane (p-BAPP), 3,3?,4,4?-benzophenetetraacarboxylic anhydride (BTDA) and p-aminopropyltrimetoxysilane (APrTMOS), is synthesized, and then phenyltrimethoxysilane; PhSi(OCH3)3 and tris(2,4-pentanedionatio) aluminum(III); Al(C5H7O2)3 are added and mixed thoroughly. Following curing, the polyimide\\/PhSiOx\\/Al2O3 hybrid films exhibit high transparency and
Mei-Hui Tsai; Yin-Kai Lin; Chi-Jung Chang; Pei-Chun Chiang; Jui-Ming Yeh; Wei-Ming Chiu; Shih-Liang Huang; Sheng-Chung Ni
Joint Chemical Agent Detector (JCAD): the future of chemical agent detection
The Joint Chemical Agent Detector (JCAD) will provide state of the art chemical warfare agent detection capability to ground vehicle operators. Intelligence sources estimate that over twenty counties have active chemical weapons programs. The spread of chemical weapons to third world nations, coupled with the potential for US involvement in these areas in an operational or support capacity, increases the probability that the Joint Services may encounter chemical agents and toxic industrial materials anywhere in the world. Currently, fielded chemical agent detectors are bulky, labor intensive, and subject to false readings. No legacy detector is sensitive enough to provide detection and warning of the low dose hazards associated with miosis contamination. The JCAD will provide a small, lightweight chemical agent detector for vehicle interiors, aircraft, individual personnel, shipboard, and fixed site locations. The system provides a common detection components across multi-service platforms. This common detector system will allow the Joint Services to use the same operational and support concept for more efficient utilization of resources. The JCAD will detect, identify, quantify, and warn of the presence of chemical agents prior to onset of miosis. Upon detection of chemical agents, the detector will provide local and remote audible and visual alarms to the operators. Advance warning will provide the vehicle crew with the time necessary to protect themselves from the lethal effects of chemical agents. The JCAD will also be capable of being upgraded to protect against future chemical agent threats. The JCAD will provide the vehicle operators with the warning necessary to survive and fight in a chemical warfare agent threat environment.
Laljer, Charles E.; Owen, Jeffery L.
Dynamics and Steady States in Excitable Mobile Agent Systems
We study the spreading of excitations in 2D systems of mobile agents where the excitation is transmitted when a quiescent agent keeps contact with an excited one during a nonvanishing time. We show that the steady states strongly depend on the spatial agent dynamics. Moreover, the coupling between exposition time (?) and agent-agent contact rate (CR) becomes crucial to understand the excitation dynamics, which exhibits three regimes with CR: no excitation for low CR, an excited regime in which the number of quiescent agents (S) is inversely proportional to CR, and, for high CR, a novel third regime, model dependent, where S scales with an exponent ?-1, with ? being the scaling exponent of ? with CR.
Peruani, Fernando; Sibona, Gustavo J.
Coalition Formation Among Autonomous Agents
Coalitions of agents can work more effectively than individual agents in many multi-agent settings. Determining which coalitions should form (i.e., what agents should work together) is a difficult problem that is typically solved by some kind of centralised planner. As the number of agents grows, however, reliance on a central authority becomes increasingly impractical. This paper formalises the coalition formation
Steven P. Ketchpel
Thermoacoustic couple
An apparatus and method for determining acoustic power density level and its direction in a fluid using a single sensor are disclosed. The preferred embodiment of the apparatus, which is termed a thermoacoustic couple, consists of a stack of thin, spaced apart polymeric plates, selected ones of which include multiple bimetallic thermocouple junctions positioned along opposite end edges thereof. The thermocouple junctions are connected in series in the nature of a thermopile, and are arranged so as to be responsive to small temperature differences between the opposite edges of the plates. The magnitude of the temperature difference, as represented by the magnitude of the electrical potential difference generated by the thermopile, is found to be directly related to the level of acoustic power density in the gas.
Wheatley, J.C.; Swift, G.W.; Migliori, A.
Agent oriented programming
The goal of our research is a methodology for creating robust software in distributed and dynamic environments. The approach taken is to endow software objects with explicit information about one another, to have them interact through a commitment mechanism, and to equip them with a speech-acty communication language. System-level applications include software interoperation and compositionality. A government application of specific interest is an infrastructure for coordination among multiple planners. Daily activity applications include personal software assistants, such as programmable email, scheduling, and new group agents. Research topics include definition of mental state of agents, design of agent languages as well as interpreters for those languages, and mechanisms for coordination within agent societies such as artificial social laws and conventions.
Shoham, Yoav
Electronic Nerve Agent Detector.
A personal field chemical warfare nerve agent detector has therein a transducer having two microchemical cantilever oscillators. One of the cantilever oscillators has deposited, as an end-mass, a chemically selective substance on the cantilever. The nerve...
E. S. Kolesar
Microencapsulation of chemotherapeutic agents.
Mixing various amounts of chemotherapeutic agents such as cisplatinum, 5-fluorouracil, mitomycin-C, and adriamycin with polymers such as poly-d, 1-lactide, ethylhydroxyethylcellulose, and polycaprolactone, several kinds of microcapsules were made. Among t...
H. S. Byun
Chemopreventive Agent Development
This group promotes and supports research on early chemopreventive agent development, from preclinical studies to phase I clinical trials. The focus is to identify and develop agents with the potential to help detect, block, reverse, or delay early stages of cancer. Preclinical studies evaluate potential new drugs and combinations in model systems using emergent knowledge of genetic and biochemical mechanisms, while early phase trials emphasize pharmacokinetics, efficacy, and safety.
Couplings of asynchronously tuned coupled microwave resonators
The papcr presents a comprehensive treatment of the couplings of asynchronously tuned coupled microwave resonators. The derived formulation allows one to extract coupling coefficients in terms of four characteristic frequencies that can be easily dctermined numerically or experiincntally. To demonstrate the applications, numerical examples are given for asynchronously tuned microstrip coupled open-loop and dual-mode resonators.
J.-S. Hong
P&G Agent Distribution
Pharmaceutical Management Branch Cancer Therapy Evaluation Program, DCTD, NCI Policy and Guidelines for INVESTIGATIONAL AGENT DISTRIBUTION Policy: The Pharmaceutical Management Branch (PMB) provides investigational agents for use
Using Adaptation and Organisational Knowledge to Coordinate Mobile Agents
\\u000a Quality of Service (QoS) routing generally requires fast reaction times, tight coupling of interactions between routing systems\\u000a and mechanisms for ensuring that actions taken throughout the network are coherent. [18] showed how an agent based QoS routing\\u000a approach can benefit significantly from making controller agents mobile and allowing them adapt the information and control\\u000a distribution in the network over time.
Steven Willmott; Boi Faltings
Smart systems and simple agents: industry pricing by parallel rules
A standard macroeconomic specification is that the aggregate economy is directed by a single, smart representative agent using optimal decision rules. This paper explores an alternative conjecture--that the dynamic behavior of markets is often better interpreted as the interactions of many heterogeneous, rule-of-thumb agents who are loosely coupled in smart systems--much like the contrast of a single serial processor with
Raymond Board; P. A. Tinsley
Agent Server Architecture for the Ajanta Mobile-Agent System
This paper provides an overview of Ajanta, aJava-based mobile-agent system, and focuses in particularon the architecture of the agent server --the process which hosts agents and enables them toaccess resources, communicate, migrate etc. Theagent server's main components include an agentexecution environment, an agent transfer protocol,a resource access protocol, and an agent monitoringservice. Security is a major concern in the designof
Neeran M. Karnik; Anand R. Tripathi
Gadofullerene MRI contrast agents.
A promising new class of MRI contrast-enhancing agents with high relaxivities is based on gadolinium-containing metallofullerenes, which are also termed gadofullerenes. Detailed study of the water-proton relaxivity properties and intermolecular nanoclustering behavior of gadofullerene derivatives has revealed valuable information about their relaxivity mechanisms and given a deeper understanding of this new class of paramagnetic contrast agent. Here, the latest findings on water-solubilized gadofullerene materials and how these findings relate to their future applications in MRI are reviewed and discussed. PMID:18373426
Bolskar, Robert D
Triglyceride-lowering agents.
This review is the first attempt at systematization of the literature data on the structures and activities of triglyceride-lowering agents which used in medical practice or are in development. The effects and mechanisms of action of statins, squalene synthase inhibitors, fibrates, PPAR? and PPAR?/? agonists, nicotinic acid, omega-3 fatty acids and some other molecular targets were considered. Unfortunately, to date, harmless and effective triglyceride-lowering drug still does not exist and there is still need for development of better triglyceride-lowering agents. PMID:24894768
Salakhutdinov, Nariman F; Laev, Sergey S
Coordination infrastructures for mobile agents
The mobile agent technology is gaining more and more interest in the distributed systems community. In this context, suitable coordination models are needed to handle the coordination, both among mobile agents and between agents and Internet resources. This paper presents two coordination infrastructures that follow two different coordination models: Aglets, based on the message-passing coordination model, and Mobile Agent Reactive
Giacomo Cabri; Letizia Leonardi; Franco Zambonelli
Sensor networks with mobile agents
Architecture for large scale low power sensor network is proposed. Referred to as sensor networks with mobile agents (SENMA), SENMA exploit node redundancies by introducing mobile agents that communicate opportunistically with a large field of sensors. The addition of mobile agents shifts computationally intensive tasks away from primitive sensors to more powerful mobile agents, which enables energy efficient operations under
Lang Tong; Qing Zhao; Srihari Adireddy
ABETA42 Lowering Agents.
The invention provides a method of preventing, delaying, or reversing the progression of Alzheimer's disease by administering an Abeta(sub 42) lowering agent to a mammal under conditions in which levels of Abeta(sub 42) are selectively reduced, levels of ...
Agents, games and HLA
Over the past decade, there has been a growing interest in utilising intelligent agents in computer games and virtual environments. At the same time, computer game research and development has increasingly drawn on technologies and techniques originally developed in the large scale distributed simulation community, such as the HLA IEEE standard for simulator interoperability. In this paper, we address a
Michael Lees; Brian Logan; Georgios K. Theodoropoulos
Aziridinyl Quinone Antitumor Agents.
The use of aziridinyl quinones as antitumor agents is disclosed. A compound which has been found to be particularly effective is the compound 2,5-diaziridinyl-3,6-bis (carboethoxyamino)-1,4-benzoquinone. Treatment is described in connection with various f...
J. S. Driscoll A. H. Khan F. Chou
J. S. Driscoll A. H. Khan F. Chow
J. S. Driscoll
Agents in Electronic Commerce
The pervasive connectivity of the Internet and the powerful architecture of World Wide Web are changing many market conventions and creating a tremendous opportunity for conducting business on Internet. Intelligent agents will play a crucial role in electronic commerce where dynamic and heterogeneous interactions between tens of thousands of organizations and tens of millions of individuals are involved. So far,
Yiming Ye; Jiming Liu; Alexandros Moukas
Agents of Infection
This is a collaborative lesson design by Lori Kern and Dawn Barone. This lesson focuses on infectious agents (fungus, bacteria, virus and parasites). Students will be able experience a hands-on activity to reinforce the concepts addressed in this benchmark.
Ferro, Michelle
Embodied mobile agents
The move in many societies toward individuals having multiple networked computational devices - workstations, notebooks computers, mobile phones, PDAs - radically changes the ways in which people engage those devices. However, we lack interaction paradigms that enable a coherent experience across these technologies. One possible approach to this problem involves the use of embodied mobile agents (EMAs), that is, graphically
Bill Tomlinson; Man Lok Yau; Eric Baumer
Remote Agent Experiment
Remote Agent (RA) is a model-based, reusable artificial intelligence (At) software system that enables goal-based spacecraft commanding and robust fault recovery. RA was flight validated during an experiment on board of DS1 between May 17th and May 21th, 1999.
Benard, Doug; Dorais, Gregory A.; Gamble, Ed; Kanefsky, Bob; Kurien, James; Millar, William; Muscettola, Nicola; Nayak, Pandu; Rouquette, Nicolas; Rajan, Kanna; Norvig, Peter (Technical Monitor)
Mobility control agent
Polymer mobility control agents useful in supplemental oil recovery processes, which give improved reciprocal relative mobilities, are prepared by initiating the polymerization of a monomer containing a vinyl group with a catalyst comprising a persulfate and ferrous ammonium sulfate. The vinyl monomer is an acrylyl, a vinyl cyanide, a styryl and water soluble salts thereof.
Argabright, P.A.; Phillips, B.L.; Rhudy, J.S.
Agent Amplified Communication
We propose an agent-based framework for assisting and simplifying person-to-person communication for informa- tion gathering tasks. As an example, we focus on expertise location within a large organization. In our approach, the informal person-to-person networks that exist within an or- ganization are used to \\
Henry A. Kautz; Bart Selman; Al Milewski
Plasmids Encoding Therapeutic Agents.
Plasmids encoding anti-HIV and anti-anthrax therapeutic agents are disclosed. Plasmid pWKK-500 encodes a fusion protein containing DP178 as a targeting moiety, the ricin A chain, an HIV protease cleavable linker, and a truncated ricin B chain. N-terminal ...
W. K. Keener
A theoretical investigation of photoacoustic contrast agents.
Photoacoustic imaging offers significant potential as a biomedical imaging modality. For some applications, however, there is a need for contrast enhancement. In this paper, a theoretical comparison is presented of the efficacy of three different designs for photoacoustic contrast agents (PACAs), specifically, a droplet of dye, a bubble filled with gas coated by a dye loaded shell, and a droplet of volatile dye. For each case, the governing equations describing the dynamics of a single PACA in a homogenous incompressible fluid are derived. The coupled sets of equations describing the bubble oscillation and resulting radiated pressure, the photo-acoustic energy equation, and the equation of state are then solved numerically. The numerical results predict a stronger radiated acoustic signal for the same optical source energy density in the case of the volatile dye droplet by a factor of up to two orders of magnitude compared with the other two types of agent. PMID:23742340
Firouzi, K; Stride, E; Saffari, N
Validating the Autonomous Science Agent
This paper describes the validation process for the Autonomous Science Agent, a software agent that will fly onboard the EO-1 spacecraft from 2003-2004. This agent will recognize science events, retarget the spacecraft to respond to the science events, and reduce data downlink to only the highest value science data. The autonomous science agent has been designed using a layered architectural approach with specific redundant safeguards to reduce the risk of an agent malfunction to the EO-1 spacecraft. This 'safe' design is also in the process of being thoroughly validated by informal validation methods and extensive testing. This paper describes the analysis used to define agent safety, elements of the design that increase the safety of the agent, and the process being used to validate agent safety prior to the agent software controlling the spacecraft.
Chien, Steve; Cichy, Benjamin; Schaffer, Steve; Tran, Danny; Rabideau, Gregg; Sherwood, Rob; Bote, Robert; Mandl, Dan; Frye, Stu; Shulman, Seth; Van Gaasbeck, Jim; Boyer, Darrell
Ubiquitous Intelligence in Agent Mining
Agent mining, namely the interaction and integration of multi-agent and data mining, has emerged as a very promising research area. While many mutual issues exist in both multi-agent and data mining areas, most of them can be described in terms of or related to ubiquitous intelligence. It is certainly very important to define, specify, represent, analyze and utilize ubiquitous intelligence in agents, data mining, and agent mining. This paper presents a novel but preliminary investigation of ubiquitous intelligence in these areas. We specify five types of ubiquitous intelligence: data intelligence, human intelligence, domain intelligence, network and web intelligence, organizational intelligence, and social intelligence. We define and illustrate them, and discuss techniques for involving them into agents, data mining, and agent mining for complex problem-solving. Further investigation on involving and synthesizing ubiquitous intelligence into agents, data mining, and agent mining will lead to a disciplinary upgrade from methodological, technical and practical perspectives.
Cao, Longbing; Luo, Dan; Zhang, Chengqi
An Architecture for Modelling Individual Behaviour and Landscape Scale Outcomes in an Intelligent Agent-Based Simulation of Environmental Management
This work describes a software architecture that couples intelligent agent technology with Geographic Information System (GIS). The agents simulate individual behaviour, while GIS-based simulation models represent the landscape that is observed and acted upon by the agents. Our motivation in developing the software is to assist in understanding and resolving complex, semi- structured, environmental management problems, where multiple actors participate
L. J. Smith; R Itami
Rigid bifunctional chelating agents
Bicyclo[2.2.2] octane-2,3 diamine-N,N,N`,N`-tetraacetic acids (BODTA) and bicyclo[2.2.1] heptane-2,3 diamine-N,N,N`,N`-tetraacetic acid (BHDTA) are chelating agents useful in forming detectably labeled bioconjugate compounds for diagnostic and therapeutic purposes. New compounds and processes of forming BODTA and BHDTA are disclosed. Radioimmunoconjugates of the present invention show high and prolonged tumor uptake with low normal tissue uptakes.
Sweet, M.P.; Mease, R.C.; Srivastava, S.C.
New antiretroviral agents
Despite advances in HIV treatment and the availability of 22 approved antiretroviral drugs, newer compounds are needed that\\u000a are better tolerated, less toxic, more convenient, or have improved activity against drug-resistant viruses. In addition to\\u000a newer agents in development in traditional antiretroviral classes (reverse transcriptase inhibitors, protease inhibitors),\\u000a a number of compounds in newer mechanistic classes also are under development,
Lawrence Siegel; Roy M. Gulick
Surface polymerization agents
This is the final report of a 1-year, Laboratory-Directed R&D project at LANL. A joint technical demonstration was proposed between US Army Missile Command (Redstone Arsenal) and LANL. Objective was to demonstrate that an unmanned vehicle or missile could be used as a platform to deliver a surface polymerization agent in such a manner as to obstruct the filters of an air-breathing mechanism, resulting in operational failure.
Taylor, C.; Wilkerson, C.
Bicyclo�2.2.2! octane-2,3 diamine-N,N,N',N'-tetraacetic acids (BODTA) and bicyclo�2.2.1! heptane-2,3 diamine-N,N,N',N'-tetraacetic acid (BHDTA) are chelating agents useful in forming detectably labeled bioconjugate compounds for diagnostic and therapeutic purposes. New compounds and processes of forming BODTA and BHDTA are disclosed. Radioimmunoconjugates of the present invention show high and prolonged tumor uptake with low normal tissue uptakes.
Sweet, Mark P. (Coram, NY); Mease, Ronnie C. (Fairfax, VA); Srivastava, Suresh C. (Setauket, NY)
Bicyclo[2.2.2]octane-2,3 diamine-N,N,N',N'-tetraacetic acids (BODTA) and bicyclo[2.2.1]heptane-2,3 diamine-N,N,N',N'-tetraacetic acid (BHDTA) are chelating agents useful in forming detectably labeled bioconjugate compounds for diagnostic and therapeutic purposes. New compounds and processes of forming BODTA and BHDTA are disclosed. Radioimmunoconjugates of the present invention show high and prolonged tumor uptake with low normal tissue uptakes.
EPA Science Inventory
A remote electrochemical biosensor for field monitoring of organophosphate nerve agents is described. The new sensor relies on the coupling of the effective biocatalytic action of organophosphorus hydrolase (OPH) with a submersible amperometric probe design. This combination resu...
From agent theory to agent construction: A case study
There is a growing body of work that concentrates on theoretical aspects of agents and multi-agent systems, and a complementary body of work concerned with building practical systems. However, the two have typically been unrelated. This gap between the theory and practice of intelligent agents has only relatively recently begun to be addressed. In this paper we describe the construction
Michael Luck; Nathan Griffiths; Mark d'Inverno
Mobile Agent Security Through Multi-Agent Cryptographic Protocols
We consider the problem of keeping sensitive data and algorithms contained in a mobile agent from discovery and exploitation by a malicious host. The fo- cus in this paper is on rigorous techniques based on cryp- tographic protocols. Algesheimer, Cachin, Camenisch, and Karjoth (IEEE Security and Privacy, 2001) devised a secure agent protocol in such a setting, where agents and
Stephen R. Tate; Ke Xu
Agents show considerable promise as a new paradigm for software development. However for wider adoption and deployment of agent technology, powerful de- sign and development tools are needed. Such tools should empower software developers to cater agent solutions more efficiently and at a lower cost for their customers with rapidly changing requirements and differing application specifi- cations. In this thesis,
Gokce Banu
The Information Agent: an infrastructure agent supporting collaborative enterprise architectures
We introduce the Information Agent as a component of the information infrastructure supporting collaborative computing environments. We discuss the functions of the Information Agent, describe an architecture based on an agent program and a knowledge management system and present out choices for these components. We show how the architecture can be designed and implemented using description logic representation systems and
Mihai Barbuceanu; Mark S. Fox
Agents in Living Color: Towards Emic Agent-Based Models
The link between agent-based models and social research is a foundational concern of this journal. In this article, the anthropological concept of 'emic' or 'insider's view' is used to foreground the value of learning what differences make a difference to actual human agents before building a model of those agents and their world. The author's Netlogo model of the epidemiology
Michael Agar
Plan Diagnosis and Agent Diagnosis in Multi-agent Systems
The paper discusses a distributed approach for monitoring and diag- nosing the execution of a plan where concurrent actions are performed by a team of cooperating agents. The paper extends the notion of plan diagnosis, introduced by Roos et al for the execution of a multi agent plan, with the notion of agent diagnosis. While plan diagnosis is able to
Roberto Micalizio; Pietro Torasso
On designing economic agents that behave like human agents
This paper explores the idea of constructing theoretical economic agents that behave like actual human agents and using them in neoclassical economic models. It does this in a repeated-choice setting by postulating artificial agents who use a learning algorithm calibrated against human learning data from psychological experiments. The resulting calibrated algorithm appears to replicate human learning behavior to a high
W. Brian Arthur
Diastereoselective pinacol coupling of alkyl aryl ketones with rare earth metals in the presence of chlorosilanes
Rare earth metals (Ln) are found to act as useful reducing agents for the pinacol coupling reaction of alkyl aryl ketones in the presence of chlorosilanes. Although the hitherto known pinacol coupling reaction using rare earth reducing agents generally exhibits very low diastereoselectivities, the present pinacol coupling by use of a LnR3SiCl system usually indicates higher diastereoselectivities. In particular, a
Akiya Ogawa; Hiroki Takeuchi; Toshikazu Hirao
Countermeasures for Mobile Agent Security.
Security is an important issue for the widespread deployment of applications based on software agent technology. It is generally agreed that without the proper countermeasures in place, use of agent-base applications will be severely impeded. However, not...
Agent-Based Systems Engineering.
This project combines robust and proven concepts from traditional mathematical systems engineering with the technology of web-based agent systems, leading to new modeling paradigms and technical results for agent-based computing. The main goal of this pro...
G. Cybenko D. Rus
Antiangiogenic agents and targets: A perspective.
The first generation of clinically useful antiangiogenic agents focused on VEGF and targets in the VEGF pathway. The strengths and limitations of these therapeutics are now clear. Some tumors do not respond to VEGF-directed therapies de novo and others become non-responsive or resistant over time by switching to other angiogenic pathways. The next generation of angiogenesis-directed therapeutics will expand the field beyond the VEGF pathway and become more disease selective. Placental growth factor, a protein closely related to VEGF, is induced as tumors lose responsiveness to VEGF-directed therapies. Angiopoietins 1 and 2 are being targeted with a unique peptibody, a human recombinant Fc constant region fused to peptides, in clinical trials. The HGF/c-Met pathway is upregulated in some tumors as an alternate angiogenic pathway. The CXCL12 (SDF-1)/CXCR4 pathway represents a stromal chemokine axis involved in tumor angiogenesis. CXCR2 is a G-protein coupled receptor with several ligands including interleukin-8 and other angiogenic cytokines and may represent a useful target for antiangiogenic agents. The notch pathway is being investigated as a target in the setting of tumor angiogenesis. Sphingosine-1-phosphate is a bioactive lipid that can be neutralized with a monoclonal antibody. The anti-S-1-P antibody is under investigation as an antiangiogenic agent. Finally, several multi-targeted kinase inhibitors each with a unique pattern of inhibitory potency are in clinical trial with a focus on antiangiogenic activity. The expansion of the scope of potential antiangiogenic agents in or entering clinical trial should allow the development of antiangiogenic combination regimens and single agents that address diseases refractory to VEGF-directed therapeutics. PMID:20920481
Teicher, Beverly A
Inactivation studies on BSE agent
Transmissible degenerative encephalopathy agents are relatively resistant to standard decontamination procedures. Bovine spongiform encephalopathy (BSE) agent was inactivated by sodium hypochlorite but not sodium dichloroisocyanurate; 1M or 2M sodium hydroxide was unreliable for BSE and scrapie agents. BSE infectivity survived a two-year exposure to formol saline. Porous-load autoclaving at 134-138�C was ineffective with BSE and scrapie agents, and resistance to
David M. Taylor
Federal Open Agent System Platform
Open Agent System platform based on High Level Architecture is firstly proposed to support the application involving heterogeneous agents. The basic idea is to develop different wrappers for different agent systems, which are wrapped as federates to join a federation. The platform is based on High Level Architecture and the advantages for this open standard are naturally inherited, such as
Hong-Bing Wang; Zhi-Hua Fan; Chun-Dong She
Security Issues in Mobile Agents
Mobile agents offer a new paradigm for distributed computation, but their potential benefits must be weighted against the very security threats they pose. These threats originate not just in malicious agents but malicious hosts as well. Thus security is a very crucial issue in dealing with mobile agent systems without which their implementation in real life applications will be rendered
Kedar Mohare
Countermeasures for mobile agent security
Security is an important issue for the widespread deployment of applications based on software agent technology. It is generally agreed that without the proper countermeasures in place, use of agent-based applications will be severely impeded. However, not all applications require the same set of countermeasures, nor can they depend entirely on the agent system to provide them. Instead, countermeasures are
Wayne A. Jansen
Mobile Agents for Mobile Computing
Mobile agents are programs that can move through a network under their own control, migratingfrom host to host and interacting with other agents and resources on each. We argue thatthese mobile, autonomous agents have the potential to provide a convenient, efficient and robustprogramming paradigm for distributed applications, particularly when partially connected computersare involved. Partially connected computers include mobile computers such
Daniela Rus; David Kotz; George Cybenko; Robert Gray; Saurab Nog
Monitoring Agents Using Declarative Planning
We present an agent monitoring approach, which aims at refuting from (possibly incomplete) information at hand that a multi-agent system (MAS) is implemented properly. In this approach, agent collaboration is abstractly de- scribed in an action theory. Action sequences reaching the collaboration goal are determined by a planner, whose compliance with the actual MAS behavior allows to detect possible collaboration
J�rgen Dix; Thomas Eiter; Michael Fink; Axel Polleres; Yingqian Zhang
A Mobile Agent Security Management
As the proliferation of Internet, mobile agent related technologies are examined for possible growth and evaluation. In information retrieval, network and distributed system management, and electronic commerce, a mobile agent is more flexible than the traditional communication paradigm. Despite the performance benefits, a mobile agent is not used widely in the market because it is very vulnerable to a variety
Eung-gu You; Keum-suk Lee
Software Agent Technology: An Overview
This chapter provides an overview of the rapidly evolving area of software agents and presents the basic aspects of applying the agent technology to virtual enterprises (VE). As the field of software agents can appear chaotic, this chapter briefly introduces the key issues rather than present an in-depth analysis and critique of the field. In addition to, this chapter investigates
Chrysanthi E. Georgakarakou; Anastasios A. Economides
Waterproofing Agents for Silica Tiles
Waterproofing agent methyltrimethoxysilane applied to silica thermal insulation tiles in simple vapor-deposition process. Other waterproofing agents in same series include methylsiloxane and hexamethyldisilazane. Originally developed for insulating tiles for spacecraft, agents also find uses in roofing tiles, insulation for buildings or solar-energy systems, or solar reflectors.
Nakano, H. N.; Izu, Y. D.; Yoshioka, E. N.
Corporate Memory Management through Agents
The CoMMA project (Corporate Memory Management through Agents) aims at developing an open, agent-based platform for the management of a corporate memory by using the most advanced results on the technical, the content, and the user interaction level. We focus here on methodologies for the set-up of multi-agent systems, requirement engineering and knowledge acquisition approaches.
Philippe PEREZ; Rose DIENG; Olivier CORBY; Fabien GANDON INRIA; Joel QUINQUETON LIRMM; Agostino POGGI; Giovanni RIMASSA; Claudio FIETTA CSELT; Juergen MUELLER; Joachim HACKSTEIN T-Nova
Contests with Many Heterogeneous Agents
We study tournaments with many ex-ante asymmetric contestants. The asymmetry is either with respect to the agents' distribution of valuations for the prize or with respect their risk-aversion (CARA) parameter. We characterize equilibria in monotone strategies and show that tournaments with many asymmetric agents are qualita- tively distinct. First, in tournaments with two asymmetric (or many symmetric) participants, an agent
Sergio O. Parreiras; Anna Rubinchik
The Anticancer Agent Adriamycin Can be Actively Cytotoxic without Entering Cells
The antineoplastic agent adriamycin was coupled to an insoluble agarose support. This material was actively cytotoxic to L1210 cells in culture under conditions in which no free adriamycin could enter the cell. It is concluded that an agent whose principal target was previously thought to be DNA can exert its cytotoxic action solely by interaction at the cell surface.
Tritton, Thomas R.; Yee, Gene
Among the Weapons of Mass Destruction, chemical warfare (CW) is probably one of the most brutal created by mankind in comparison with biological and nuclear warfare. Chemical weapons are inexpensive and are relatively easy to produce, even by small terrorist groups, to create mass casualties with small quantities. The characteristics of various CW agents, general information relevant to current physical as well as medical protection methods, detection equipment available and decontamination techniques are discussed in this review article. A brief note on Chemical Weapons Convention is also provided. PMID:21829312
Ganesan, K; Raza, S K; Vijayaraghavan, R
Dynamical Consensus Algorithm for Second-Order Multi-Agent Systems Subjected to Communication Delay
To solve the dynamical consensus problem of second-order multi-agent systems with communication delay, delay-dependent compensations are added into the normal asynchronously-coupled consensus algorithm so as to make the agents achieve a dynamical consensus. Based on frequency-domain analysis, sufficient conditions are gained for second-order multi-agent systems with communication delay under leaderless and leader-following consensus algorithms respectively. Simulation illustrates the correctness of the results.
Liu, Cheng-Lin; Liu, Fei
Second-order cluster consensus of multi-agent dynamical systems with impulsive effects
This paper discuss the cluster consensus of multi-agent dynamical systems (MADSs) with impulsive effects and coupling delays. Some sufficient conditions that guarantee cluster consensus in MADS are derived. In each cluster, agents update their position and velocity states according to a leader's instantaneous information, and interactions among agents are uncertain. Furthermore, switching topology problem in MADS is considered by impulsive stability and adaptive strategy. Finally, numerical simulations are given to verify our theoretical analysis.
Wang, Guan; Shen, Yi
Workshop report: Velocity coupling
Velocity coupled combustion instability and related combustion instability topics were considered. The knowledge of velocity coupled combustion instability was assessed; the state of the art of velocity coupled measurement techniques was determined; and particularly laboratory devices or T burner related devices; recommendations were made on how to improve the state of knowledge on velocity coupled combustion instability. Test conditions for a round robin of velocity coupled response measurement techniques were established.
Beckstead, M. W.
Flexible, secure agent development framework
While an agent generator is generating an intelligent agent, it can also evaluate the data processing platform on which it is executing, in order to assess a risk factor associated with operation of the agent generator on the data processing platform. The agent generator can retrieve from a location external to the data processing platform an open site that is configurable by the user, and load the open site into an agent substrate, thereby creating a development agent with code development capabilities. While an intelligent agent is executing a functional program on a data processing platform, it can also evaluate the data processing platform to assess a risk factor associated with performing the data processing function on the data processing platform.
Goldsmith; Steven Y. (Rochester, MN)
Lipid-lowering agents.
The role of lipid lowering in reducing the risk of mortality and morbidity from cardiovascular disease (CVD) is well established. Treatment particularly aimed at decreasing low-density lipoprotein cholesterol (LDL-C) is effective in reducing the risk of death from coronary heart disease and stroke. Statins form the cornerstone of treatment. However, in some individuals with a high risk of CVD who are unable to achieve their target LDL-C due to either intolerance or lack of efficacy, there is the need for alternative therapies. This review provides an overview of the different classes of currently available lipid-lowering medications including statins, fibrates, bile acid sequestrants (resins), and omega-3 fatty acids. Data are presented on their indications, pharmacology, and the relevant end point clinical trial data with these drugs. It also discusses the human trial data on some novel therapeutic agents that are being developed including those for homozygous familial hypercholesterolemia--the antisense oligonucleotide mipomersen and the microsomal transfer protein inhibitor lomitapide. Data are presented on phase II and III trials on agents with potentially wider applications, cholesterol ester transfer protein inhibitors and proprotein convertase subtilisin kexin 9 inhibitors. The data on a licensed gene therapy for lipoprotein lipase deficiency are also presented. PMID:23811423
Ewang-Emukowhate, Mfon; Wierzbicki, Anthony S
Holograms as Teaching Agents
Hungarian physicist Dennis Gabor won the Pulitzer Prize for his 1947 introduction of basic holographic principles, but it was not until the invention of the laser in 1960 that research scientists, physicians, technologists and the general public began to seriously consider the interdisciplinary potentiality of holography. Questions around whether and when Three-Dimensional (3-D) images and systems would impact American entertainment and the arts would be answered before educators, instructional designers and students would discover how much Three-Dimensional Hologram Technology (3DHT) would affect teaching practices and learning environments. In the following International Symposium on Display Holograms (ISDH) poster presentation, the author features a traditional board game as well as a reflection hologram to illustrate conventional and evolving Three-Dimensional representations and technology for education. Using elements from the American children's toy Operation� (Hasbro, 2005) as well as a reflection hologram of a human brain (Ko, 1998), this poster design highlights the pedagogical effects of 3-D images, games and systems on learning science. As teaching agents, holograms can be considered substitutes for real objects, (human beings, organs, and animated characters) as well as agents (pedagogical, avatars, reflective) in various learning environments using many systems (direct, emergent, augmented reality) and electronic tools (cellphones, computers, tablets, television). In order to understand the particular importance of utilizing holography in school, clinical and public settings, the author identifies advantages and benefits of using 3-D images and technology as instructional tools.
Walker, Robin A.
Climate-Seismicity Coupling
Topic of the slow climate changes is rather popular at present. Two important problems are usually discussing in connection with the climate variability: several years quasi-periodicity (El Nino/La Nino effect) and long-term trend in the global temperature (global warming or cooling). Concerning forcing agent on the climate changes several hypotheses have been suggested including changes in solar luminosity, variations in the Earth's orbit around the Sun, cosmic rays, volcanic eruption activity and so on but the most accepted cause is the change in atmospheric greenhouse gas concentrations due to human activity. We have tried to find a correlation between slow climate changes using variation in sstoi indices (sea surface temperature anomalies in the 3 selected areas of near-equatorial Pacific Ocean, 160E-90W) and seismic activity using USGS catalog on crustal earthquakes (EQs) in about the same areas. We calculate the values that are proportional to seismic energy release as indices of seismic activity and compare the variation of half-year sstoi and seimic indicies during period of 1973-2008. Autocorrelation of both indices smoothed by 1-year window shows the same behavior in the all selected regions with averaged 4.5 year periodicity while the cross-correlation of the indices envisages 1.5-2 years time delay of sstoi indices in relation to seismic indices. Such the mother-daughter delay is checked by comparison of deep and crustal seismic activity using technique that described in the paper [1]. Furthermore there is clear similarity in the trends of sstoi and seismic indices. We conclude that slow climate variations are probably induced by changes in natural seismicity. Energetic estimations of the climate-seismicity coupling are also discussed. [1] O.A. Mochanov and S. Uyeda, Upward migration of earthquake hypocenters in Japan, Kurile-Kamchatka and Sunda subduction zones, Physics and Chemistry, 2008, doi:10.1016/j.pce.2008.09.011.
Molchanov, O.
Quick connect coupling
A coupling device has a transversely arranged, open-end groove in a flange attached to a pipe end. The groove in the flange receives a circumferentially arranged locking flange element on the other coupling member and permits alignment of the bores of the coupling members when the locking flange element is in the open end groove. Upon alignment of the bores of the coupling members, a trigger member is activated to automatically release a spring biased tubular member in one of the coupling members. The tubular member has a conical end which is displaced into the other coupling member to lock the coupling members to one another. A tensioning nut is threadedly movable on a coupling member so as to be moved into tightening engagement with the other coupling member.
Sprague, Benny B. (inventor)
The Work-Centered Couple.
Sketches taxonomy of work-centered couple. Briefly describes five couple types: the dual-career couple, the commuting couple, the military couple, the executive couple, and the family business couple. Notes that issues of work and career can greatly impact the lives of these couples. Encourages family psychology to further explore this area of�
Sperry, Len; Carlson, Jon
Fluoroquinolone antimicrobial agents.
The fluoroquinolones, a new class of potent orally absorbed antimicrobial agents, are reviewed, considering structure, mechanisms of action and resistance, spectrum, variables affecting activity in vitro, pharmacokinetic properties, clinical efficacy, emergence of resistance, and tolerability. The primary bacterial target is the enzyme deoxyribonucleic acid gyrase. Bacterial resistance occurs by chromosomal mutations altering deoxyribonucleic acid gyrase and decreasing drug permeation. The drugs are bactericidal and potent in vitro against members of the family Enterobacteriaceae, Haemophilus spp., and Neisseria spp., have good activity against Pseudomonas aeruginosa and staphylococci, and (with several exceptions) are less potent against streptococci and have fair to poor activity against anaerobic species. Potency in vitro decreases in the presence of low pH, magnesium ions, or urine but is little affected by different media, increased inoculum, or serum. The effects of the drugs in combination with a beta-lactam or aminoglycoside are often additive, occasionally synergistic, and rarely antagonistic. The agents are orally absorbed, require at most twice-daily dosing, and achieve high concentrations in urine, feces, and kidney and good concentrations in lung, bone, prostate, and other tissues. The drugs are efficacious in treatment of a variety of bacterial infections, including uncomplicated and complicated urinary tract infections, bacterial gastroenteritis, and gonorrhea, and show promise for therapy of prostatitis, respiratory tract infections, osteomyelitis, and cutaneous infections, particularly when caused by aerobic gram-negative bacilli. Fluoroquinolones have also proved to be efficacious for prophylaxis against travelers' diarrhea and infection with gram-negative bacilli in neutropenic patients. The drugs are effective in eliminating carriage of Neisseria meningitidis. Patient tolerability appears acceptable, with gastrointestinal or central nervous system toxicities occurring most commonly, but only rarely necessitating discontinuance of therapy. In 17 of 18 prospective, randomized, double-blind comparisons with another agent or placebo, fluoroquinolones were tolerated as well as or better than the comparison regimen. Bacterial resistance has been uncommonly documented but occurs, most notably with P. aeruginosa and Staphylococcus aureus and occasionally other species for which the therapeutic ratio is less favorable. Fluoroquinolones offer an efficacious, well-tolerated, and cost-effective alternative to parenteral therapies of selected infections.
Wolfson, J S; Hooper, D C
Evaluating Competing Agent Strategies for a Voice Email Agent
This paper reports experimental results comparing a mixed-initiative to a system-initiative dialog strategy i n the context of a personal voice email agent. To independently test the effects of dialog strategy and user expertise, user s in- teract with either the system-initiative or the mixed-init iative agent to perform three successive tasks which are identical for both agents. We report
Marilyn A. Walker; Donald Hindle; Jeanne Fromer; Giuseppe Di Fabbrizio; Craig Mestel
[Unconventional antidiabetic agents].
The current pharmacological therapy of type 2 diabetes reduces the risk of diabetic complications, but is not able to achieve a long-lasting normalization of the metabolic disorder. Thus diabetic patients in increasing numbers are taking dietary supplements and herbs from which they expect additional health benefits. These unconventional antidiabetic agents consist mainly in trace metals like chromium, vanadium and zinc and a heterogeneous group of traditionally used antidiabetic herbs (e. g. Momordica charantia, Gymnema sylvestre, Trigonella foenum-graecum) often derived from the ayurvedic medicine. In this overview the current evidence for the antidiabetic effect is presented. The trace elements chromium and vanadium have a number of potentially antidiabetic actions in vitro, however, the results obtained with diabetic patients are not convincing so far. Similarly, the available data on the therapeutic use of herbs suggest that in principle a number of them possess a blood glucose-lowering effect, but at present no firm conclusions as to their efficacy and safety can be made. To set up reliable dose-effect relationships requires the identification of the relevant antidiabetic molecules as was apparently achieved by isolating 4-hydroxyisoleucine from the seeds of T. foenum-graecum. This requirement is also valid in the case of the antidiabetic action of cinnamon. Coffee and a moderate alcohol consumption were found to be surprisingly effective in lowering the risk of type 2 diabetes manifestation, their effect being roughly equal to that of conventional drugs used in diabetes prevention trials. Diabetic patients should inform their physician about the use of unconventional agents and should be warned against uncontrolled starting or stopping their use. PMID:17484443
Rustenbeck, Ingo
Field Test of Two Spill Treating Agents.
Laboratory effectiveness tests are described for four classes of spill-treating agents; solidifiers, demulsifying agents, surface-washing agents and dispersants. Many treating agents in these four categories have been tested for effectiveness and the resu...
Agent-based enterprise integration
The authors are developing and deploying software agents in an enterprise information architecture such that the agents manage enterprise resources and facilitate user interaction with these resources. The enterprise agents are built on top of a robust software architecture for data exchange and tool integration across heterogeneous hardware and software. The resulting distributed multi-agent system serves as a method of enhancing enterprises in the following ways: providing users with knowledge about enterprise resources and applications; accessing the dynamically changing enterprise; locating enterprise applications and services; and improving search capabilities for applications and data. Furthermore, agents can access non-agents (i.e., databases and tools) through the enterprise framework. The ultimate target of the effort is the user; they are attempting to increase user productivity in the enterprise. This paper describes their design and early implementation and discusses the planned future work.
N. M. Berry; C. M. Pancerella
The authors are developing and deploying software agents in an enterprise information architecture such that the agents manage enterprise resources and facilitate user interaction with these resources. Their enterprise agents are built on top of a robust software architecture for data exchange and tool integration across heterogeneous hardware and software. The resulting distributed multi-agent system serves as a method of enhancing enterprises in the following ways: providing users with knowledge about enterprise resources and applications; accessing the dynamically changing enterprise; intelligently locating enterprise applications and services; and improving search capabilities for applications and data. Furthermore, agents can access non-agents (i.e., databases and tools) through the enterprise framework. The ultimate target of their effort is the user; they are attempting to increase user productivity in the enterprise. This paper describes their design and early implementation and discusses their planned future work.
Collaborating Fuzzy Reinforcement Learning Agents
Earlier, we introduced GARIC-Q, a new method for doing incremental Dynamic Programming using a society of intelligent agents which are controlled at the top level by Fuzzy Relearning and at the local level, each agent learns and operates based on ANTARCTIC, a technique for fuzzy reinforcement learning. In this paper, we show that it is possible for these agents to compete in order to affect the selected control policy but at the same time, they can collaborate while investigating the state space. In this model, the evaluator or the critic learns by observing all the agents behaviors but the control policy changes only based on the behavior of the winning agent also known as the super agent.
Berenji, Hamid R.
Surface preparation and coupling in plastic scintillator dosimetry.
One way to improve the performance of scintillation dosimeters is to increase the light-collection efficiency at the coupling interfaces of the detector system. We performed a detailed study of surface preparation of scintillating fibers and their coupling with clear optical fibers to minimize light loss and increase the amount of light collected. We analyzed fiber-surface polishing with aluminum oxide sheets, coating fibers with magnesium oxide, and the use of eight different coupling agents (air, three optical gels, an optical curing agent, ultraviolet light, cyanoacrylate glue, and acetone). We prepared 10 scintillating fiber and clear optical fiber light guide samples to test different coupling methods. To test the coupling, we first cut both the scintillating fiber and the clear optical fiber. Then, we cleaned and polished both ends of both fibers. Finally, we coupled the scintillating fiber with the clear optical fiber in either a polyethylene jacket or a V-grooved support depending on the coupling agent used. To produce more light, we used an ultraviolet lamp to stimulate scintillation. A typical series of similar couplings showed a standard deviation in light-collection efficiency of 10%. This can be explained by differences in the surface preparation quality and alignment of the scintillating fiber with the clear optical fiber. Absence of surface polishing reduced the light collection by approximately 40%, and application of magnesium oxide on the proximal end of the scintillating fiber increased the amount of light collected from the optical fiber by approximately 39%. Of the coupling agents, we obtained the best results using one of the optical gels. Because a large amount of the light produced inside a scintillator is usually lost, better light-collection efficiency will result in improved sensitivity. PMID:17022248
Ayotte, Guylaine; Archambault, Louis; Gingras, Luc; Lacroix, Fr�d�ric; Beddar, A Sam; Beaulieu, Luc
Surface preparation and coupling in plastic scintillator dosimetry
One way to improve the performance of scintillation dosimeters is to increase the light-collection efficiency at the coupling interfaces of the detector system. We performed a detailed study of surface preparation of scintillating fibers and their coupling with clear optical fibers to minimize light loss and increase the amount of light collected. We analyzed fiber-surface polishing with aluminum oxide sheets, coating fibers with magnesium oxide, and the use of eight different coupling agents (air, three optical gels, an optical curing agent, ultraviolet light, cyanoacrylate glue, and acetone). We prepared 10 scintillating fiber and clear optical fiber light guide samples to test different coupling methods. To test the coupling, we first cut both the scintillating fiber and the clear optical fiber. Then, we cleaned and polished both ends of both fibers. Finally, we coupled the scintillating fiber with the clear optical fiber in either a polyethylene jacket or a V-grooved support depending on the coupling agent used. To produce more light, we used an ultraviolet lamp to stimulate scintillation. A typical series of similar couplings showed a standard deviation in light-collection efficiency of 10%. This can be explained by differences in the surface preparation quality and alignment of the scintillating fiber with the clear optical fiber. Absence of surface polishing reduced the light collection by approximately 40%, and application of magnesium oxide on the proximal end of the scintillating fiber increased the amount of light collected from the optical fiber by approximately 39%. Of the coupling agents, we obtained the best results using one of the optical gels. Because a large amount of the light produced inside a scintillator is usually lost, better light-collection efficiency will result in improved sensitivity.
Ayotte, Guylaine; Archambault, Louis; Gingras, Luc; Lacroix, Frederic; Beddar, A. Sam; Beaulieu, Luc [Departement de physique, de genie physique et d'optique, Universite Laval, Quebec City, Quebec, G1K7P4 (Canada) and Departement de Radio-Oncologie, Hotel Dieu de Quebec, Centre Hospitalier Universitaire de Quebec, Quebec City, Quebec, G1R2J6 (Canada); Departement de physique, de genie physique et d'optique, Universite Laval, Quebec City, Quebec, G1K7P4 (Canada) and Department de Radio-Oncologie, Hotel Dieu de Quebec, Centre Hospitalier Universitaire de Quebec, Quebec City, Quebec, G1R2J6 (Canada) and Department of Radiation Physics, Division of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, Texas 77030 (United States); Department de physique, de genie physique et d'optique, Universite Laval, Quebec City, Quebec, G1K7P4 (Canada) and Department de Radio-Oncologie, Hotel Dieu de Quebec, Centre Hospitalier Universitaire de Quebec, Quebec City, Quebec, G1R2J6 (Canada); Department of Radiation Physics, Division of Radiation Oncology, University of Texas M.D. Anderson Cancer Center, Houston, Texas 77030 (United States); Department de physique, de genie physique et d'optique, Universite Laval, Quebec City, Quebec, G1K7P4 (Canada) and Department de Radio-Oncologie, Hotel Dieu de Quebec, Centre Hospitalier Universitaire de Quebec, Quebec City, Quebec, G1R2J6 (Canada)
3D Emotional Agent Architecture
\\u000a This chapter presents architecture to design emotional agents evolving in an artificial 3D environment. The agent behavior\\u000a and environment emulator are independent of implementation. To achieve this, a Language of Interface for Animations in 3D\\u000a called LIA-3D, is presented. The agent and environment simulator uses LIA to establish communication with each other.
F�lix F. Ramos; Luis Razo; Alma V. Martinez; Fabiel Z��iga; H. Ivan Piza
Agent-based autonomous Examination Systems
Online computerized examination systems is developed using software agent technology. Multi-agent system containing main agent, mobile agent and stationery agent is developed to support the functionality of examination systems in Aglet environment. All these agents in the system communicate with each other to process the operations requested by the user. Authentication of the examinee for valid user name and password
R. D. Gawali; B. B. Meshram
Antisocial Behavior of Agents in Scheduling Mechanisms
Truthful task scheduling mechanisms are designed to cope with the selfishness of the participating agents. They assume that the agents are selfish; each agent's goal is to maximize its own profit. However, this is not always the case; an agent may want to cause losses to the other agents besides maximizing its profit. Such an agent is said to be
Nandan Garg; Daniel Grosu; Vipin Chaudhary
Applet: Coupled Oscillators
This website from Dr. Wolfgang Bauer at the University of Michigan contains a java applet which allows the user to change certain parameters while observing simulated coupled oscillators. In the process of coupled oscillations, energy is transferred between the individual oscillators. This is how waves propagate. Here you can study this with the most simple example of two coupled spring oscillators.
Bauer, W. (Wolfgang), 1959-
Bioresponsive, Cell-Penetrating and Multimeric MR Contrast Agents
Conspectus Magnetic resonance imaging (MRI) has become increasingly popular in molecular imaging and clinical radiology because it is non-invasive and capable of producing three-dimensional representations of opaque organisms with high spatial and temporal resolution. While approximately 35% of all clinical MR scans utilize contrast media, a primary limitation of MR imaging is the low sensitivity to detect contrast agents requiring high concentrations of agent for enhanced signal intensity (0.1-0.6 mM).1 A number of strategies have been employed to amplify the observed in vivo signal of MR contrast agents. Approaches include attachment of Gd(III) chelates to polymers, proteins and particles, encapsulation into micelles and caged structures, and targeting to receptors. While each of these approaches has yielded significant increases in the relaxivity of MR contrast agents (and therefore sensitivity), all of these classes of complexes possess intrinsic background signal and function solely as anatomical reporters due to their constitutive activity. In order to reduce the background signal and simultaneously create probes that are modulated by biochemical events, caged complexes were designed to coordinatively saturate the paramagnetic ion. Coupled with amplification strategies, these agents represent a means to selectively modulate the observed MR signal and function as in vivo biochemical reporters. For example, to create an in vivo MR assay of enzymatic activities and secondary messengers, agents have been designed and synthesized with removable protection groups that largely prevent access of water to a paramagnetic center. By limiting the access of bulk water (q-modulation) the unprocessed agent is designed to be an ineffective contrast agent, and hence serves as a reliable marker for regions of enzyme activity or secondary messengers. In this Account we describe our results toward designing new classes of MR agents that are i. responsive to in vivo physiological or biochemical events ii. cell-permeable to increase local concentration, and iii. attached to large molecules or are synthesized with multiply labeled conjugates for signal amplification.
Major, Jody L.; Meade, Thomas J.
Agent Tcl: A flexible and secure mobile-agent system
A mobile agent is an autonomous program that can migrate under its own control from machine to machine in a heterogeneous network. In other words, the program can suspend its execution at an arbitrary point, transport itself to another machine, and then resume execution from the point of suspension. Mobile agents have the potential to provide a single, general framework
Robert S. Gray
Incorporating BDI Agents into Human-Agent Decision Making Research
Artificial agents, people, institutes and societies all have the ability to make decisions. Decision making as a research area therefore involves a broad spectrum of sciences, ranging from Artificial Intelligence to economics to psychology. The Colored Trails (CT) framework is designed to aid researchers in all fields in examining decision making processes. It is developed both to study interaction between multiple actors (humans or software agents) in a dynamic environment, and to study and model the decision making of these actors. However, agents in the current implementation of CT lack the explanatory power to help understand the reasoning processes involved in decision making. The BDI paradigm that has been proposed in the agent research area to describe rational agents, enables the specification of agents that reason in abstract concepts such as beliefs, goals, plans and events. In this paper, we present CTAPL: an extension to CT that allows BDI software agents that are written in the practical agent programming language 2APL to reason about and interact with a CT environment.
Kamphorst, Bart; van Wissen, Arlette; Dignum, Virginia
Concept features in Re:Agent, an intelligent Email agent
An important issue in the application of machine learningtechniques to information management tasks is the natureof features extracted from textual information. We have createdan intelligent email agent that can learn actions suchas filtering, prioritizing, downloading to palmtops, and forwardingemail to voicemail using automatic feature extraction.Our agent's new feature extraction approach is basedon first learning concepts present within the mail, then
Gary Boone
TACtic- A Multi Behavioral Agent for Trading Agent Competition
Software agents are increasingly being used to represent humans in online auctions. Such agents have the advantages of being able to systematically monitor a wide variety of auctions and then make rapid decisions about what bids to place in what auctions. They can do this continuously and repetitively without losing concentration. To provide a means of evaluating and comparing (benchmarking) research methods in this area the trading agent competition (TAC) was established. This paper describes the design, of TACtic. Our agent uses multi behavioral techniques at the heart of its decision making to make bidding decisions in the face of uncertainty, to make predictions about the likely outcomes of auctions, and to alter the agent's bidding strategy in response to the prevailing market conditions.
Khosravi, Hassan; Shiri, Mohammad E.; Khosravi, Hamid; Iranmanesh, Ehsan; Davoodi, Alireza
New micellar transfection agents.
Two novel micelle-forming amino-functionalized lipids (OT6 and TT6) bearing two alkyl chains connected to a large positively charged hexavalent headgroup, which might be interesting polynucleotide transferring agents with the advantage of an easy and reproducible production of micelle dispersions, have been characterized. The critical micelle concentration (cmc) of both lipids has been determined by two different methods, namely, isothermal titration calorimetry (ITC) and 1,6-diphenyl-1,3,5-hexatriene (DPH) fluorescence experiments. In addition, the lipid dispersions were studied as a function of temperature using differential scanning calorimetry (DSC), dynamic light scattering (DLS), Fourier-transform infrared (FT-IR) spectroscopy, and cryo-transmission electron microscopy (cryo-TEM). The OT6 and TT6 micelles effectively complex DNA as determined by ITC and DSC measurements. In addition, DLS and ?-potential measurements were performed to determine lipoplex formulations that exhibit colloidal stability. Finally, the structures of OT6/DNA complexes were investigated by means of X-ray scattering and TEM. PMID:24697720
W�lk, Christian; Pawlowska, Dorota; Drescher, Simon; Auerswald, Anna; Meister, Annette; Hause, Gerd; Blume, Alfred; Langner, Andreas; Brezesinski, Gerald; Dobner, Bodo
Contrast agents for MRI.
Contrast agents are divided into two categories. The first one is paramagnetic compounds, including lanthanides like gadolinium, which mainly reduce the longitudinal (T1) relaxation property and result in a brighter signal. The second class consists of super-paramagnetic magnetic nanoparticles (SPMNPs) such as iron oxides, which have a strong effect on the transversal (T2) relaxation properties. SPMNPs have the potential to be utilized as excellent probes for magnetic resonance imaging (MRI). For instance, clinically benign iron oxide and engineered ferrite nanoparticles provide a good MRI probing capability for clinical applications. Furthermore, the limited magnetic property and inability to escape from the reticuloendothelial system (RES) of the used nanoparticles impede their further advancement. Therefore, it is necessary to develop the engineered magnetic nanoparticle probes for the next-generation molecular MRI. Considering the importance of MRI in diagnosing diseases, this paper presents an overview of recent scientific achievements in the development of new synthetic SPMNP probes whereby the sensitive and target-specific observation of biological events at the molecular and cellular levels is feasible. PMID:24094150
Shokrollahi, H
Plasmids encoding therapeutic agents
Plasmids encoding anti-HIV and anti-anthrax therapeutic agents are disclosed. Plasmid pWKK-500 encodes a fusion protein containing DP178 as a targeting moiety, the ricin A chain, an HIV protease cleavable linker, and a truncated ricin B chain. N-terminal extensions of the fusion protein include the maltose binding protein and a Factor Xa protease site. C-terminal extensions include a hydrophobic linker, an L domain motif peptide, a KDEL ER retention signal, another Factor Xa protease site, an out-of-frame buforin II coding sequence, the lacZ.alpha. peptide, and a polyhistidine tag. More than twenty derivatives of plasmid pWKK-500 are described. Plasmids pWKK-700 and pWKK-800 are similar to pWKK-500 wherein the DP178-encoding sequence is substituted by RANTES- and SDF-1-encoding sequences, respectively. Plasmid pWKK-900 is similar to pWKK-500 wherein the HIV protease cleavable linker is substituted by a lethal factor (LF) peptide-cleavable linker.
Keener, William K. (Idaho Falls, ID)
Coupled Fano resonators.
We theoretically investigate coupled Fano structures which combine the characteristics of both directly coupled Fabry-Perot cavities (DCFPC) and a side-coupled integrated spaced sequence of resonators (SCISSOR). Asymmetric and symmetric Fano resonances in a single and doubly-coupled Fano unit are analytically derived based on Fabry-Perot approach. It is found that doubly-coupled Fano units show a special asymmetric EIT-like lineshape. This structure shows an index changing sensitivity of 10(-6), about two orders higher than that of the single Fano resonator, which is promising for index sensor application. A unique frequency detuning method of EIT like lineshape is also found in the doubly-coupled Fano units. The multiple coupled Fano unit structure demonstrates potentials for applications of tunable optical filter and slow light, whereas for the latter it shows much higher group delay than that of SCISSORS and DCFPC with the same parameters. PMID:20940775
Tu, Xiaoguang; Mario, Landobasa Y; Mei, Ting
Agent Model Development for Assessing Climate-Induced Geopolitical Instability.
We present the initial stages of development of new agent-based computational methods to generate and test hypotheses about linkages between environmental change and international instability. This report summarizes the first year's effort of an originally proposed three-year Laboratory Directed Research and Development (LDRD) project. The preliminary work focused on a set of simple agent-based models and benefited from lessons learned in previous related projects and case studies of human response to climate change and environmental scarcity. Our approach was to define a qualitative model using extremely simple cellular agent models akin to Lovelock's Daisyworld and Schelling's segregation model. Such models do not require significant computing resources, and users can modify behavior rules to gain insights. One of the difficulties in agent-based modeling is finding the right balance between model simplicity and real-world representation. Our approach was to keep agent behaviors as simple as possible during the development stage (described herein) and to ground them with a realistic geospatial Earth system model in subsequent years. This work is directed toward incorporating projected climate data--including various C02 scenarios from the Intergovernmental Panel on Climate Change (IPCC) Third Assessment Report--and ultimately toward coupling a useful agent-based model to a general circulation model.3
Boslough, Mark B.; Backus, George A.
Insurance Agents: Licensing and Regulation.
In many respects the insurance agent is the most important person in the insurance transaction. In most cases he represents the public's only contact with the insurance company. The insured depends upon the competence of the agent to provide insurance to ...
G. A. Freedman
Gelled Anti-icing Agents
Pectin added to antifreeze/water mixture. Formulations include water with dimethyl sulfoxide (DMSO) as deicer and pectin as gel former. Without gelling agent, deicer runs off vertical surfaces. Without pectin solution will completely evaporate in far less time. Agents developed have wide potential for ice prevention on runways, highways, bridges and sidewalks.
Markles, O. F.; Sperber, H. H.
Language Support for Mobile Agents
Mobile agents are code-containing objects that may be transmitted between communicatingparticipants in a distributed system. As opposed to systems that onlyallow the exchange of nonexecutable data, systems incorporating mobile agentscan achieve significant gains in performance and functionality.A programming language for mobile agents must be able to express theirconstruction, transmission, receipt, and subsequent execution. Its implementationmust handle architectural heterogeneity...
Frederick Colville Knabe
Agent-oriented software engineering
Software and knowledge engineers continually strive to develop tools and techniques to manage the complexity that is inherent in the systems they have to build. In this article, we argue that intelligent agents and agent-based systems oer novel opportunities for developing eective tools and techniques. Following a discussion on the classic subject of what makes software complex, we introduce intelligent
P. Ciancarini; M. Wooldridge
A Simple Shill Bidding Agent
Shill bidding is where fake bids are introduced into an auction to drive up the final price for the seller, thereby defrauding legitimate bidders. Although shill bidding is strictly forbidden in online auctions such as eBay, it is still a major problem. This paper presents a software bidding agent that follows a shill bidding strategy. The malicious bidding agent was
Jarrod Trevathan; Wayne Read
Itinerant agents for mobile computing
Describes a framework for itinerant agents that can be used to implement secure, remote applications in large, public networks such as the Internet or the IBM Global Network. Itinerant agents are programs, dispatched from a source computer, that roam among a set of networked servers until they accomplish their task. This is an extension to the client\\/server model in which
David Chess; Benjamin Grosof; Colin Harrison; David Levine; Colin Parris; Gene Tsudik
Agent-Based Literacy Theory
The purpose of this theoretical essay is to explore the limits of traditional conceptualizations of reader and text and to propose a more general theory based on the concept of a literacy agent. The proposed theoretical perspective subsumes concepts from traditional theory and aims to account for literacy online. The agent-based literacy theory�
McEneaney, John E.
Coalitions Among Computationally Bounded Agents
This paper analyzes coalitions among self-interested agents that need to solve combinatorial optimization problems to operate efficiently in the world. By colluding (coordinating their actions by solving a joint optimization problem) the agents can sometimes save costs compared to operating individually. A model of bounded rationality is adopted where computation resources are costly. It is not worthwhile solving the problems
Tuomas W. Sandhlom; Victor R. T Lesser
Nerve Agent Sensing Biopolymer Wipe.
This research and development project entitled 'Nerve Agent Sensing Biopolymer Wipe' is directed at developing a simple-to-use enzyme-containing sensor for detecting nerve agent contamination at surfaces, in air and in solution, and to provide a tool for ...
M. Erbeldinger K. LeJeune
Artificial agents learning human fairness
Recent advances in technology allow multi-agent systems to be de- ployed in cooperation with or as a service for humans. Typically, those systems are designed assuming individually rational agents, according to the principles of classical game theory. However, re- search in the field of behavioral economics has shown that humans are not purely self-interested: they strongly care about fairness. Therefore,
Steven De Jong; Karl Tuyls; Katja Verbeeck
AL Amyloidosis and Agent Orange
... with Agent Orange � AL Amyloidosis and Agent Orange Public Health Public Health Public Health Home Military Exposures Military Exposures Home 4 Ways ... Publications & Reports About Us About the Office of Public Health Post-Deployment Health Clinical Public Health About Clinical ...
Empathic Touch by Relational Agents
We describe a series of experiments with an agent designed to model human conversational touch-capable of physically touching users in synchrony with speech and other nonverbal communicative behavior-and its use in expressing empathy to users in distress. The agent is composed of an animated human face that is displayed on a monitor affixed to the top of a human mannequin,
Timothy W. Bickmore; Rukmal Fernando; Lazlo Ring; Daniel Schulman
Agent-Oriented Software Engineering
theoretical model of computation that more closely reflects current computing reality than Turing Machines. Agents are being advocated as the next generation model for engineering complex distributed systems. Agents are also being used as an over-arching framework for bringing together the component AI sub-disciplines that are necessary to design and build intelligent entities. Despite this intense interest, however, a number
Nicholas R. Jennings
Intelligent Agents: Theory and Practice
The concept of an agent has become important in both Artificial Intelligence (AI) and mainstream computer science. Our aim in this paper is to point the reader at what we perceive to be the most important theoretical and practical issues associated with the design and construction of intelligent agents. For convenience, we divide these issues into three areas (though as
Michael Wooldridge; Nicholas R. Jennings
Dynamic pricing by software agents
We envision a future in which the global economy and the Internetwill merge and evolve together into an information economy bustling withbillions of economically motivated software agents that exchange informationgoods and services with humans and other agents. Economic softwareagents will differ in important ways from their human counterparts, andthese differences may have significant beneficial or harmful effects uponthe global economy.
Jeffrey O. Kephart; James E. Hanson; Amy R. Greenwald
Agent-based collaborative manufacturing
The current rapidly changing market requires unprecedented levels of interoperability between enterprises. The framework presented in this paper allows the implementation of highly flexible distributed agent-based supply chain systems. Starting from the customer's initial request an entire network of suppliers is generated automatically. Agents in our framework can change roles dynamically, collaborate and compete against each other to offer the
Liviu Cotfas; Andreea Diosteanu; Ion Smeureanu
Markov Tracking for Agent Coordination
Partially observable Markov decision processes (POMDPs) axe an attractive representation for representing agent behavior, since they capture uncertainty in both the agent's state and its actions. However, finding an optimal policy for POMDPs in general is computationally difficult. In this paper we present Markov Tracking, a restricted problem of coordinating actions with an agent or process represented as a POMDP Because the actions coordinate with the agent rather than influence its behavior, the optimal solution to this problem can be computed locally and quickly. We also demonstrate the use of the technique on sequential POMDPs, which can be used to model a behavior that follows a linear, acyclic trajectory through a series of states. By imposing a "windowing" restriction that restricts the number of possible alternatives considered at any moment to a fixed size, a coordinating action can be calculated in constant time, making this amenable to coordination with complex agents.
Washington, Richard; Lau, Sonie (Technical Monitor)
Intelligent Agents in Physics Education
Intelligent Agents are being applied in a wide range of processes and everyday applications. Their development is not new, in recent years they have had an increased attention and design; like learning and mentoring tools. In this work we discuss the definition of what an intelligent agent is; how they are applied; how they look like; recent implementations of agents; agents as support in the learning process, more precisely intelligent tutors; their state in Latin-American countries and future developments and trends that will permit a better communication between people and agents. Also we present an Intelligent Tutor applied as a tool for improving high-school students' skills and reasoning for the first five topics of Mechanics curricula.
S�nchez-Guzm�n, D.; Mora, C�sar
Knowledge focus via software agents
The essence of military Command and Control (C2) is making knowledge intensive decisions in a limited amount of time using uncertain, incorrect, or outdated information. It is essential to provide tools to decision-makers that provide: * Management of friendly forces by treating the "friendly resources as a system". * Rapid assessment of effects of military actions againt the "enemy as a system". * Assessment of how an enemy should, can, and could react to friendly military activities. Software agents in the form of mission agents, target agents, maintenance agents, and logistics agents can meet this information challenge. The role of each agent is to know all the details about its assigned mission, target, maintenance, or logistics entity. The Mission Agent would fight for mission resources based on the mission priority and analyze the effect that a proposed mission's results would have on the enemy. The Target Agent (TA) communicates with other targets to determine its role in the system of targets. A system of TAs would be able to inform a planner or analyst of the status of a system of targets, the effect of that status, adn the effect of attacks on that system. The system of TAs would also be able to analyze possible enemy reactions to attack by determining ways to minimize the effect of attack, such as rerouting traffic or using deception. The Maintenance Agent would scheudle maintenance events and notify the maintenance unit. The Logistics Agent would manage shipment and delivery of supplies to maintain appropriate levels of weapons, fuel and spare parts. The central idea underlying this case of software agents is knowledge focus. Software agents are createad automatically to focus their attention on individual real-world entities (e.g., missions, targets) and view the world from that entities perspective. The agent autonomously monitors the entity, identifies problems/opportunities, formulates solutions, and informs the decision-maker. The agent must be able to communicate to receive and disseminate information and provide the decision-maker with assistance via focused knowledge. THe agent must also be able to monitor the state of its own environment and make decisions necessary to carry out its delegated tasks. Agents bring three elements to the C2 domain that offer to improve decision-making. First, they provide higher-quality feedback and provide it more often. In doing so, the feedback loop becomes nearly continuous, reducing or eliminating delays in situation updates to decision-makers. Working with the most current information possible improves the control process, thus enabling effects based operations. Second, the agents accept delegation of actions and perform those actions following an established process. Agents' consistent actions reduce the variability of human input and stabilize the control process. Third, through the delegation of actions, agents ensure 100 percent consideration of plan details.
Henager, Donald E.
Entropy and self-organization in multi-agent systems
Emergent self-organization in multi-agent systems appears to contradict the second law of thermodynamics. This paradox has been explained in terms of a coupling between the macro level that hosts self-organization (and an apparent reduction in entropy), and the micro level (where random processes greatly increase entropy). Metaphorically, the micro level serves as an entropy �sink�, permitting overall system entropy to
H. Van Dyke Parunak; Sven Brueckner
Separation and analysis of lanthanides by isotachophoresis coupled with inductively coupled plasma mass spectrometry.
This study is a large project initiated by the French Nuclear Agency, and concerns the development of a new electrolyte system for the separation of lanthanides by isotachophoresis. This new system is based on a leading electrolyte that incorporates 2-hydroxy-2-methylbutyric acid as complexing agent. The optimization of separation conditions (complexing agent concentration, pH, capillary dimensions, injection conditions, and current intensity) performed by experiments on a commercial capillary instrument with contactless conductivity detection, which allows to improve the separation of 13 lanthanides (La to Lu, except Pm and Ho). We have also directly coupled the isotachophoresis to an inductively coupled plasma mass spectrometer to visualize the mono-elementary elution bands and demonstrate the potentiality of the method for isotope ratio measurements. The application to a simulated solution representative of a fraction of fission products present in a MOX spent fuel is presented in this paper to demonstrate the possible application in future on nuclear fuel samples. PMID:22967598
Vio, Laurent; Cr�tier, G�rard; Chartier, Fr�d�ric; Geertsen, Val�rie; Gourgiotis, Alkiviadis; Isnard, H�l�ne; Rocca, Jean-Louis
Three tooth kinematic coupling
A three tooth kinematic coupling based on having three theoretical line contacts formed by mating teeth rather than six theoretical point contacts. The geometry requires one coupling half to have curved teeth and the other coupling half to have flat teeth. Each coupling half has a relieved center portion which does not effect the kinematics, but in the limit as the face width approaches zero, three line contacts become six point contacts. As a result of having line contact, a three tooth coupling has greater load capacity and stiffness. The kinematic coupling has application for use in precision fixturing for tools or workpieces, and as a registration device for a work or tool changer or for optics in various products.
Hale, Layton C. (Livermore, CA)
Agent Communications using Distributed Metaobjects
There are currently two proposed standards for agent communication languages, namely, KQML (Finin, Lobrou, and Mayfield 1994) and the FIPA ACL. Neither standard has yet achieved primacy, and neither has been evaluated extensively in an open environment such as the Internet. It seems prudent therefore to design a general-purpose agent communications facility for new agent architectures that is flexible yet provides an architecture that accepts many different specializations. In this paper we exhibit the salient features of an agent communications architecture based on distributed metaobjects. This architecture captures design commitments at a metaobject level, leaving the base-level design and implementation up to the agent developer. The scope of the metamodel is broad enough to accommodate many different communication protocols, interaction protocols, and knowledge sharing regimes through extensions to the metaobject framework. We conclude that with a powerful distributed object substrate that supports metaobject communications, a general framework can be developed that will effectively enable different approaches to agent communications in the same agent system. We have implemented a KQML-based communications protocol and have several special-purpose interaction protocols under development.
Goldsmith, Steven Y.; Spires, Shannon V.
Novel agents in indolent lymphomas
Indolent non-Hodgkin�s lymphomas (iNHLs) include follicular lymphomas (FL), marginal-zone lymphoma, lymphoplasmacytic lymphoma/Waldenstr�m macroglobulinemia and small lymphocytic lymphoma. First-line standard therapy in advanced, symptomatic iNHL consists of rituximab-based immunochemotherapy. The recent rediscovery of the �old� chemotherapeutic agent bendamustine, an alkylating agent with a peculiar mechanism of action, has added a new effective and well-tolerated option to the therapeutic armamentarium in iNHL, increasing response rates and duration. However, patients invariably relapse and subsequent active and well-tolerated agents are needed. In recent years a large number of new targeted agents have been tested in preclinical and clinical experimentation in FL and indolent nonfollicular lymphoma (iNFL), including the new monoclonal antibodies binding CD20 or other surface antigens, immunoconjugates and bispecific antibodies. Moreover novel agents directed against intracellular processes such as proteasome inhibitors, mTOR inhibitors and agents that target the tumour microenvironment, notably the immunomodulatory agent lenalidomide, are under active clinical investigation. The development of these new drugs may change in the near future the approach to iNHL patients, leading to better tolerated and effective therapy regimens.
Merli, Michele; Ferrario, Andrea; Basilico, Claudia; Maffioli, Margherita; Caramazza, Domenica; Appio, Lorena; Arcaini, Luca
Photodynamic agents with anti-metastatic activities.
A new concept in multifunctional anticancer agents is demonstrated. Tetrakis-(diisopropyl-guanidino) zinc phthalocyanine (Zn-DIGP) exhibits excellent properties as a photodynamic therapy (PDT) agent, as well as potential anti-metastatic activities in vivo. Zn-DIGP exhibits good cellular uptake and low toxicity in the dark (EC50 > 80 ?M) and is well tolerated upon its intravenous injection into mice at 8 mg/kg. Upon photoexcitation with red laser light (660 nm), Zn-DIGP exhibits a high quantum yield for singlet oxygen formation (? ? 0.51) that results in potent phototoxicity to cell cultures (EC50 ? 0.16 ?M). Zn-DIGP is also capable of inhibiting the formation of tumor colonies in the lungs of C57BL/6 mice injected with B16F10 cells. Zn-DIGP therefore inhibits cancer growth by both light-dependent and light-independent pathways. The anti-metastatic activities of Zn-DIGP possibly result from its ability to interfere with the signaling between chemokine CXCL10 and the G protein-coupled receptor CXCR3. Zn-DIGP is a competitive inhibitor of CXCR3 activation (IC50 = 3.8 ?M) and selectively inhibits downstream events such as CXCL10-activated cell migration. Consistent with the presence of feedback regulation between CXCR3 binding and CXCL10 expression, Zn-DIGP causes overexpression of CXCL10. Interestingly, Zn-DIGP binds to CXCR3 without activating the receptor yet is able to cause endocytosis and degradation of this GPCR. To the best of our knowledge, Zn-DIGP is the first PDT agent that can facilitate the photodynamic treatment of primary tumors while simultaneously inhibiting the formation of metastatic tumor colonies by a light-independent mode of action. PMID:23672401
Vummidi, Balayeshwanth R; Noreen, Faiza; Alzeer, Jawad; Moelling, Karin; Luedtke, Nathan W
Orwell's Nightmare for Agents? Programming Multi-agent Organisations
This paper presents a programming language that is designed to implement multi-agent organisations. These organisations are\\u000a developed as separate entities regulating the behaviour of individual agents that interact with the organisation. The focus\\u000a is on the normative aspect of organisations that are specified in terms of norms being enforced by monitoring, regimenting\\u000a and sanctioning mechanisms.
Nick A. M. Tinnemeier; Mehdi Dastani; John-jules Ch. Meyer
Bulking agents: a urogynecology perspective.
A bulking agent is a material injected into the wall of the urethra to improve urethral coaptation in women suffering from stress incontinence. The concept was initially described in the 1930s when sodium morrhuate and paraffin were used to augment urethral resistance. Sclerosing agents were also used for inducing permanent urethral scaring to improve urinary leakage. Eventually, collagen and autologous fat were found to be efficacious, and only collagen demonstrated proven safety and endured extensive testing, becoming the gold standard for injectable agents. Since then, multiple other products have been developed by the industry, each with its particular success rates and complications. PMID:22877709
Zoorob, Dani; Karram, Mickey
Requirements Modeling with Agent Programming
Agent-oriented conceptual modeling notations are highly effective in representing requirements from an intentional stance and answering questions such as what goals exist, how key actors depend on each other, and what alternatives must be considered. In this chapter, we review an approach to executing i* models by translating these into set of interacting agents implemented in the CASO language and suggest how we can perform reasoning with requirements modeled (both functional and non-functional) using i* models. In this chapter we particularly incorporate deliberation into the agent design. This allows us to benefit from the complementary representational capabilities of the two frameworks.
Dasgupta, Aniruddha; Krishna, Aneesh; Ghose, Aditya K.
Nuclear magnetic resonance contrast agents
A family of contrast agents for use in magnetic resonance imaging and a method of enhancing the contrast of magnetic resonance images of an object by incorporating a contrast agent of this invention into the object prior to forming the images or during formation of the images. A contrast agent of this invention is a paramagnetic lanthanide hexaazamacrocyclic molecule, where a basic example has the formula LnC.sub.16 H.sub.14 N.sub.6. Important applications of the invention are in medical diagnosis, treatment, and research, where images of portions of a human body are formed by means of magnetic resonance techniques.
Smith, Paul H. (Los Alamos, NM); Brainard, James R. (Los Alamos, NM); Jarvinen, Gordon D. (Los Alamos, NM); Ryan, Robert R. (Los Alamos, NM)
A family of contrast agents for use in magnetic resonance imaging and a method of enhancing the contrast of magnetic resonance images of an object by incorporating a contrast agent of this invention into the object prior to forming the images or during formation of the images. A contrast agent of this invention is a paramagnetic lanthanide hexaazamacrocyclic molecule, where a basic example has the formula LnC{sub 16}H{sub 14}N{sub 6}. Important applications of the invention are in medical diagnosis, treatment, and research, where images of portions of a human body are formed by means of magnetic resonance techniques. 10 figs.
Smith, P.H.; Brainard, J.R.; Jarvinen, G.D.; Ryan, R.R.
Nonlinearity induced critical coupling.
We study a critically coupled system [Opt. Lett. 32, 1483 (2007)] with a Kerr nonlinear spacer layer. Nonlinearity is shown to inhibit null scattering in a critically coupled system at low powers. However, a system detuned from critical coupling can exhibit near-complete suppression of scattering by means of nonlinearity-induced changes in refractive index. Our studies reveal clearly an important aspect of critical coupling as a delicate balance in both the amplitude and the phase relations, while a nonlinear resonance in dispersive bistability concerns only the phase. PMID:23939099
Nireekshan Reddy, K; Gopal, Achanta Venu; Dutta Gupta, S
Time-variant distributed agent matching applications
The process of pair partnership formation is an important infrastructure for many plausible MAS applications. Each agent evaluates potential partner agents, where each potential match yields a different utility. Commonly, the utility associated with a given agent partner in such two-sided search processes may change over time. This change in the agent�s future attractiveness to potential partners significantly increases the
David Sarne; Sarit Kraus
Adapting to agents' personalities in negotiation
To establish cooperative relationships, agents must be willing to engage in helpful behavior and to keep their commitments to other agents. However, in uncertain and dynamic environments, it is difficult to identify the degree of helpfulness of other agents. This paper describes a model in which agents' helpfulness is characterized in terms of cooperation and reliability. An agent chooses an
Shavit Talman; Meirav Hadad; Ya'akov Gal; Sarit Kraus
Performance Evaluation of Mobile Agent Network
The paper deals with performance evaluation of a mobile agent network that includes a multi-agent system and a set of processing nodes connected by a communication network where it resides and operates. A mobile agent network is described as a queuing system where an agent represents an information unit to be served. Agent hosting, execution and migration are defined as
Ignac LOVREK; Vjekoslav SINKOVIC
Asymmetric interpersonal coupling in a cyclic sports-related movement task.
In interactive sports, teammates and/or opponents mutually tune their behavior. Expert performance thus implies certain interactive abilities, which critically depend on perceptual coupling. To illustrate this assertion, we examined the coordination dynamics with asymmetric interaction of dyads performing a sports-related cyclical movement task. In pairs, basketball players performed lateral defensive slides in in-phase, until a cue prompted them to switch to antiphase coordination. We assessed how these switches were mediated by phase adaptations of each agent under bidirectional (i.e., agents facing one another) and unidirectional (i.e., one agent facing the back of the other) visual interaction conditions. This imposed asymmetry in visual coupling exemplified an imbalance in the interaction (or 'interact-ability') between two agents. The results concurred the asymmetric coupling: during the switch the agent facing the other adapted his phasing more than the other agent. Furthermore, also in the bidirectional condition the coupling revealed dyad-intrinsic asymmetries (e.g., related to implicit follower-leader strategies). Together, this illustrates that interpersonal coordination is characterized by asymmetric coupling between the agents, and highlights how mutual perception of pertinent information mediates interpersonal coordination. This study offered a first step towards analyzing interpersonal coordination dynamics in relation to 'interact-ability'. PMID:24835161
Meerhoff, L Rens A; De Poel, Harjo J
Diamine curing agents for polyurethanes
Three aromatic diamines have properties that make them promising candidates as curing agents for converting isocyanates to polyurethanes with higher adhesive strengths, higher softening temperatures, better toughness, and improved abrasion resistance.
Bell, V. L.; St. Clair, T. L.
Triggered pore-forming agents
An inactive pore-forming agent which is activated to lytic function by a condition such as pH, light, heat, reducing potential, or metal ion concentration, or substance such as a protease, at the surface of a cell.
Bayley, Hagan (Grafton, MA); Walker, Barbara J. (Auburn, MA); Chang, Chung-yu (Worcester, MA); Niblack, Brett (Nashville, TN); Panchal, Rekha (Shrewsbury, MA)
Launch Commit Criteria Monitoring Agent
The Spaceport Processing Systems Branch at NASA Kennedy Space Center has developed and deployed a software agent to monitor the Space Shuttle's ground processing telemetry stream. The application, the Launch Commit Criteria Monitoring Agent, increases situational awareness for system and hardware engineers during Shuttle launch countdown. The agent provides autonomous monitoring of the telemetry stream, automatically alerts system engineers when predefined criteria have been met, identifies limit warnings and violations of launch commit criteria, aids Shuttle engineers through troubleshooting procedures, and provides additional insight to verify appropriate troubleshooting of problems by contractors. The agent has successfully detected launch commit criteria warnings and violations on a simulated playback data stream. Efficiency and safety are improved through increased automation.
Semmel, Glenn S.; Davis, Steven R.; Leucht, Kurt W.; Rowe, Dan A.; Kelly, Andrew O.; Boeloeni, Ladislau
Intelligent agents: theory and practice
Abstract The concept of an agent has become,important in both Artificial Intelligence (AI) and mainstream,computer,science. Our aim in this paper is to point the reader at what we perceive to be the most important theoretical and practical issues as sociated with the design and construction of intelligent agents. For convenience, we divide these issues into three areas (though as the
M. Woolridge; N. Jennings
Making Agents Acceptable to People
Because ever more powerful intelligent agents will interact with people in increasingly sophisticated and important ways,\\u000a greater attention must be given to the technical and social aspects of how to make agents acceptable to people [4], p. 51]. The technical challenge is to devise a computational structure that guarantees that from the technical standpoint\\u000a all is under control. We want
Jeffrey M. Bradshaw; Patrick Beautement; Maggie R. Breedy; Larry Bunch; Sergey V. Drakunov; Paul J. Feltovich; Robert R. Hoffman; Renia Jeffers; Matthew Johnson; Shriniwas Kulkarnt; James Lott; Anil K. Raj; Niranjan Suri; Andrzej Uszok
Intelligent agent for collaborative diagnosis.
An agent-based approach to facilitating cooperative medical diagnosis is presented in this paper. Background work in computer supported cooperative work and medical informatics is first discussed. Relevant theory for interaction management is then considered. An agent-based interaction is then shown via a case study to facilitate cooperative diagnosis. This is achieved through monitoring patient record construction and by highlighting relevant diagnostic information. PMID:10384453
Mulvihill, C; Patel, A; O'Meara, T
Perceiving Environments for Intelligent Agents
One of the important characteristics for intelligent agents is to be able to assess their environments in order to decide\\u000a on the correct action to take. It is always difficult to do so because many factors including uncertain information, knowledge\\u000a and bounded time will affect intelligent agent to perceive their environments. In this paper, we propose a procedure descriptive\\u000a framework
Yuefeng Li; Chengqi Zhang
Ultrasound Contrast Agent Microbubble Dynamics
\\u000a Ultrasound contrast agents are traditionally used in ultrasound-assisted organ perfusion imaging. Recently the use of coated\\u000a microbubbles has been proposed for molecular imaging applications where the bubbles are covered with a layer of targeting\\u000a ligands to bind specifically to their target cells. In this chapter we describe contrast agent microbubble behavior starting\\u000a from the details of free bubble dynamics leading
Marlies Overvelde; Hendrik J. Vos; Jong de Nico; Michel Versluis; Gaio Paradossi; Paolo Pellegretti; Andrea Trucco
An abstract knowledge based approach to diagnosis and recovery of plan failure in multi-agent systems
Open multi-agent systems (MAS) are decentralised and distributed systems that consist of a large number of loosely coupled autonomous agents. In the absence of centralised control they tend to be difficult to manage, especially in an open environment, which is dynamic, complex, distributed and unpredictable. This dynamism and uncertainty in an open environment gives rise to unexpected plan failures. In
Nazaraf Shah; Kuo-ming Chao; Anthony N. Godwin; Anne E. James
Coupled Oscillation Simulation
This applet simulates a harmonic coupled line of masses moving in one dimension. The number and size of loads, damping, speed of the simulation and stiffness of the springs are adjustable, and the phases and magnitudes of the normal modes are shown. The applet also simulates elastic collisions and weak couplings and demonstrates lissajous figures. Source code is included.
Falstad, Paul
Understanding Dual Career Couples.
Presents an overview of the published literature delineating variables associated with dual career couples, including the numerous benefits or incentives, common conflicts and stressors, and the personality dynamics shared by these couples. Dysfunctional coping strategies as well as adaptive strategies are also described. (Author)
Parker, Marolyn; And Others
Translation-coupling systems
Disclosed are systems and methods for coupling translation of a target gene to a detectable response gene. A version of the invention includes a translation-coupling cassette. The translation-coupling cassette includes a target gene, a response gene, a response-gene translation control element, and a secondary structure-forming sequence that reversibly forms a secondary structure masking the response-gene translation control element. Masking of the response-gene translation control element inhibits translation of the response gene. Full translation of the target gene results in unfolding of the secondary structure and consequent translation of the response gene. Translation of the target gene is determined by detecting presence of the response-gene protein product. The invention further includes RNA transcripts of the translation-coupling cassettes, vectors comprising the translation-coupling cassettes, hosts comprising the translation-coupling cassettes, methods of using the translation-coupling cassettes, and gene products produced with the translation-coupling cassettes.
Pfleger, Brian; Mendez-Perez, Daniel
24 CFR 232.1011 - Management agents.
Code of Federal Regulations, 2013 CFR
...and Restrictions on Fund Distributions § 232.1011 Management agents. (a...amendments to such management agent agreements...that provides for a management agent to have rights to or claims on funds owed to the...
Intelligent Agent Architectures: Reactive Planning Testbed.
An Integrated Agent Architecture (IAA) is a framework or paradigm for constructing intelligent agents. Intelligent agents are collections of sensors, computers, and effectors that interact with their environments in real time in goal-directed ways. Becaus...
S. J. Rosenschein P. Kahn
Coupled nano-plasmons
A simple model of coupled plasmons arising in two neighbouring nano-particles is presented. The coupled oscillations and the corresponding eigenfrequencies are computed. It is shown that the plasmons may be periodically transferred between the two particles. For larger separation distances between the two particles the retardation is included. The oscillation eigenmodes are the polaritons in this case. There are distances for which the particles do not couple to each other, i.e. the polaritonic coupling gets damped. The van der Waals-London-Casimir force is estimated for the two particles; it is shown that for large distances the force is repulsive. We compute also the polarizabilities of the two coupled nano-particles and their cross-section under the action of an external monochromatic plane wave, which exhibit resonances indicative of light trapping and field enhancement. A resonant force is also identified, acting upon the particles both on behalf of the external field and of each other.
Apostol, M.; Ilie, S.; Petrut, A.; Savu, M.; Toba, S.
Ground energy coupling
The feasibility of ground coupling for various heat pump systems was investigated. Analytical heat flow models were developed to approximate design ground coupling devices for use in solar heat pump space conditioning systems. A digital computer program called GROCS (GRound Coupled Systems) was written to model 3-dimensional underground heat flow in order to simulate the behavior of ground coupling experiments and to provide performance predictions which have been compared to experimental results. GROCS also has been integrated with TRNSYS. Soil thermal property and ground coupling device experiments are described. Buried tanks, serpentine earth coils in various configurations, lengths and depths, and sealed vertical wells are being investigated. An earth coil used to heat a house without use of resistance heating is described.
Metz, P. D.
Exponentially modified QCD coupling
We present a specific class of models for an infrared-finite analytic QCD coupling, such that at large spacelike energy scales the coupling differs from the perturbative one by less than any inverse power of the energy scale. This condition is motivated by the Institute for Theoretical and Experimental Physics operator product expansion philosophy. Allowed by the ambiguity in the analytization of the perturbative coupling, the proposed class of couplings has three parameters. In the intermediate energy region, the proposed coupling has low loop-level and renormalization scheme dependence. The present modification of perturbative QCD must be considered as a phenomenological attempt, with the aim of enlarging the applicability range of the theory of the strong interactions at low energies.
Cvetic, Gorazd [Department of Physics, Universidad Tecnica Federico Santa Maria, Valparaiso (Chile); Center of Subatomic Studies, UTFSM, Valparaiso (Chile); Valenzuela, Cristian [Department of Physics, Universidad Tecnica Federico Santa Maria, Valparaiso (Chile)
The Coupling Controversy
Functional magnetic resonance imaging (fMRI) relies on the well-known phenomenon of coupling between neuronal activity and brain blood flow. For nearly a century, the presumption was that hemodynamics were coupled to neuronal activity via energy demand and oxidative metabolism. Early 15O positron-emission tomographic (PET) studies challenged this theory, demonstrating a physiological �uncoupling� between brain blood flow and oxygen metabolism. These PET observations played a pivotal role in guiding the development of fMRI, by demonstrating which physiological parameters were most closely coupled to neuronal activity and by presaging the BOLD-contrast effect. Subsequent PET studies were crucial for constraining theories concerning the physiological mechanisms underlying hemodynamic/neuronal coupling and, thereby, guiding the development of models for quantification of oxygen metabolic rate %? from fMRI. A first-person account of the PET �coupling� studies and their influence on the development of fMRI is provided.
Fox, Peter T.
Layered Learning in Multi-Agent Systems
Multi-agent systems in complex, real-time domains require agents to act effectively both autonomously and as part of a team. This dissertation addresses multi-agent systems consisting of teams of autonomous agents acting in real-time, noisy, collaborative, and adversarial environments. Because of the inherent complexity of this type of multi-agent system, this thesis investigates the use of machine learning within multi-agent systems.
Peter Stone
Methods for Protecting a Mobile Agent's Route
In the world of mobile agents, security aspects are extensively being discussed, with strong emphasis on how agents can be\\u000a protected against malicious hosts and vice versa. This paper discusses methods for protecting an agent�s route information\\u000a from being misused by sites en route interested in gaining insight into the profile of the agent�s owner or in obstructing\\u000a the owner�s
Dirk Westhoff; Markus Schneider II; Claus Unger; Firoz Kaderali
Distributed event dissemination for ubiquitous agents
Software agent technology is based on event-driven entities that use asynchronous messaging and high-level languages to communicate. Agents may subscribe information from other agents, update their internal models based on received messages and notifications, and publish notifications to listening agents. Currently, most agent architectures do not employ content-based dissemination of messages or notifications, and the agents need to take care
Sasu Tarkoma
Partner switching promotes cooperation among myopic agents on a geographical plane
We study the coupling dynamics between the evolution of cooperation and the evolution of partnership network on a geographical plane. While agents play networked prisoner�s dilemma games, they can dynamically adjust their partnerships based on local information about reputation. We incorporate geographical features into the process of the agent�s partner switching and investigate the corresponding effects. At each time step of the coevolution, a random agent can either update his strategy by imitation or adjust his partnership by switching from the lowest reputation partner to the highest reputation one among his neighbors. We differentiate two types of neighbors: geographical neighbors (i.e., the set of agents who are close to the focal agent in terms of geographical distance) and connectivity neighbors (i.e., the set of agents who are close to the focal agent in the partnership network in terms of geodesic distance). We find that switching to either geographical neighbors or connectivity neighbors enhances cooperation greatly in a wide parameter range. Cooperation can be favored in a much stricter condition when agents switch to connectivity neighbors more frequently. However, an increasing tendency of reconnecting to geographical neighbors shortens the geographical distance between a pair of partners on average. When agents consider the cost of geographical distance in adjusting the partnership, they are prone to reconnect to geographical neighbors.
Li, Yixiao; Min, Yong; Zhu, Xiaodong; Cao, Jie
Caring for Agents and Agents that Care: Building Empathic Relations with Synthetic Agents
When building agents and synthetic characters, and in order to achieve believability, we must consider the emotional relations established between users and characters, that is, we must consider the issue of \\
Ana Paiva; Joao Dias; Daniel Sobral; Ruth Aylett; Polly Sobreperez; Sarah Woods; Carsten Zoll; Lynne E. Hall
Depression: The Differing Narratives of Couples in Couple Therapy
How does the spouse of a person with depression take part in constructing narratives of depression in couple therapy? In this study we examined couples' ways of co-constructing narratives of depression in couple therapy. Three couple therapy processes were chosen for the study, one spouse in each couple having been referred to an outpatient clinic�
Rautiainen, Eija-Liisa; Aaltonen, Jukka
Heterogeneously coupled neural oscillators
The work we present in this thesis is a series of studies of how heterogeneities in coupling affect the synchronization of coupled neural oscillators. We begin by examining how heterogeneity in coupling strength affects the equilibrium phase difference of a pair of coupled, spiking neurons when compared to the case of identical coupling. This study is performed using pairs of Hodgkin-Huxley and Wang-Buzsaki neurons. We find that heterogeneity in coupling strength breaks the symmetry of the bifurcation diagrams of equilibrium phase difference versus the synaptic rate constant for weakly coupled pairs of neurons. We observe important qualitative changes such as the loss of the ubiquitous in-phase and anti-phase solutions found when the coupling is identical and regions of parameter space where no phase locked solution exists. Another type of heterogeneity can be found by having different types of coupling between oscillators. Synaptic coupling between neurons can either be exciting or inhibiting. We examine the synchronization dynamics when a pair of neurons is coupled with one excitatory and one inhibitory synapse. We also use coupled pairs of Hodgkin-Huxley neurons and Wang-Buzsaki neurons for this work. We then explore the existance of 1 : n coupled states for a coupled pair of theta neurons. We do this in order to reproduce an observed effect called quantal slowing. Quantal slowing is the phenomena where jumping between different 1 : n coupled states is observed instead of gradual changes in period as a parameter in the system is varied. All of these topics fall under the general heading of coupled, non-linear oscillators and specifically weakly coupled, neural oscillators. The audience for this thesis is most likely going to be a mixed crowd as the research reported herein is interdisciplinary. Choosing the content for the introduction proved far more challenging than expected. It might be impossible to write a maximally useful introductory portion of a thesis when it could be read by a physicist, mathematician, engineer or biologist. Undoubtedly readers will find some portion of this introduction elementary. At the risk of boring some or all of my readers we decided it was best to proceed so that enough of the mathematical (biological) background is explained in the introduction so that a biologist (mathematician) is able to appreciate the motivations for the research and the results presented. We begin with an introduction in nonlinear dynamics explaining the mathematical tools we use to characterize the excitability of individual neurons, as well as oscillations and synchrony in neural networks. The next part of the introductory material is an overview of the biology of neurons. We then describe the neuron models used in this work and finally describe the techniques we employ to study coupled neurons.
Bradley, Patrick J.
Contactless Rotary Electrical Couplings
Rotary electrical couplings based on induction (transformer action) rather than conduction between rotating and stationary circuitry have been invented. These couplings provide an alternative to slip rings and contact brushes. Mechanical imperfections of slip-ring and brush contact surfaces and/or dust particles trapped between these surfaces tend to cause momentary interruptions in electrical contact and thereby give rise to electrical noise. This source of noise can be eliminated in the inductive rotary couplings because no direct contact is necessary for transformer action.
Kumagai, Hiroyuki
The oxidative coupling of methane over potassium-modified antimony oxide
The current interest in the direct conversion of methane higher homologs reflects the commercial importance of nay such technology. Direct conversion has not yet proven successful mainly because the direct coupling of methane is a thermodynamically prohibited process at temperatures and pressures of interest. If an oxidizing agent is present, however, either partial oxidation to methanol or oxidative coupling can
M. Y. Lo; S. Agarwal; G. Marcelin
Investigational antimicrobial agents of 2013.
New antimicrobial agents are always needed to counteract the resistant pathogens that continue to be selected by current therapeutic regimens. This review provides a survey of known antimicrobial agents that were currently in clinical development in the fall of 2012 and spring of 2013. Data were collected from published literature primarily from 2010 to 2012, meeting abstracts (2011 to 2012), government websites, and company websites when appropriate. Compared to what was reported in previous surveys, a surprising number of new agents are currently in company pipelines, particularly in phase 3 clinical development. Familiar antibacterial classes of the quinolones, tetracyclines, oxazolidinones, glycopeptides, and cephalosporins are represented by entities with enhanced antimicrobial or pharmacological properties. More importantly, compounds of novel chemical structures targeting bacterial pathways not previously exploited are under development. Some of the most promising compounds include novel ?-lactamase inhibitor combinations that target many multidrug-resistant Gram-negative bacteria, a critical medical need. Although new antimicrobial agents will continue to be needed to address increasing antibiotic resistance, there are novel agents in development to tackle at least some of the more worrisome pathogens in the current nosocomial setting. PMID:24092856
Pucci, Michael J; Bush, Karen
Next Generation Remote Agent Planner
In May 1999, as part of a unique technology validation experiment onboard the Deep Space One spacecraft, the Remote Agent became the first complete autonomous spacecraft control architecture to run as flight software onboard an active spacecraft. As one of the three components of the architecture, the Remote Agent Planner had the task of laying out the course of action to be taken, which included activities such as turning, thrusting, data gathering, and communicating. Building on the successful approach developed for the Remote Agent Planner, the Next Generation Remote Agent Planner is a completely redesigned and reimplemented version of the planner. The new system provides all the key capabilities of the original planner, while adding functionality, improving performance and providing a modular and extendible implementation. The goal of this ongoing project is to develop a system that provides both a basis for future applications and a framework for further research in the area of autonomous planning for spacecraft. In this article, we present an introductory overview of the Next Generation Remote Agent Planner. We present a new and simplified definition of the planning problem, describe the basics of the planning process, lay out the new system design and examine the functionality of the core reasoning module.
Jonsson, Ari K.; Muscettola, Nicola; Morris, Paul H.; Rajan, Kanna
An agent based framework for virtual medical devices
In this paper we present the telemedical environment based on VMDs implemented with Java mobile agent technology, called aglets. The agent based VMD implementation provides ad-hoc agent interaction, support for mobile agents and different user interface components in the telemedical system. We have developed a VMD agent framework with four types of agents: data agents, processing agents, presentation agents, and
Zeljko Obrenovic; Dusan Starcevic; Emil Jovanov; Vlada Radivojevic
Spatial process and data models: Toward integration of agent-based models and GIS
The use of object-orientation for both spatial data and spatial process models facilitates their integration, which can allow exploration and explanation of spatial-temporal phenomena. In order to better understand how tight coupling might proceed and to evaluate the possible functional and efficiency gains from such a tight coupling, we identify four key relationships affecting how geographic data (fields and objects) and agent-based process models can interact: identity, causal, temporal and topological. We discuss approaches to implementing tight integration, focusing on a middleware approach that links existing GIS and ABM development platforms, and illustrate the need and approaches with example agent-based models.
Brown, Daniel G.; Riolo, Rick; Robinson, Derek T.; North, Michael; Rand, William
Professional Couples and Money.
This study investigates three alternative models of the distribution of financial control in dual-earner couples: one derived from resource theory, one from socialization theory and an equality model based on marital satisfaction research. 88 high income,...
S. Yogev J. M. Brett
Methods of delivering pharmaceutical agents
Provided are methods of delivering at least one pharmaceutical agent to the central nervous system (CNS) of a subject, methods of treating a neurological disorder or pain in a subject that include administering at least one pharmaceutical agent onto a SEM graft in the skull base of the subject. Also provided are methods of treating a neurological disorder or pain in a subject that include forming a SEM graft in the skull base of the subject and administering at least one pharmaceutical agent onto the SEM graft in the skull base of the subject. Also provided are methods of forming a SEM graft in the skull base of a subject, compositions for administration onto a SEM graft in the skull base or into an endonasal reservoir or endonasal reservoir device in a subject, and devices for administering such compositions onto a SEM graft in the skull base of a subject.
Coupled transverse motion
The magnetic field in an accelerator or a storage ring is usually so designed that the horizontal (x) and the vertical (y) motions of an ion are uncoupled. However, because of imperfections in construction and alignment, some small coupling is unavoidable. In this lecture, we discuss in a general way what is known about the behaviors of coupled motions in two degrees-of-freedom. 11 refs., 6 figs.
Teng, L.C.
Thyroid dysfunction from antineoplastic agents.
Unlike cytotoxic agents that indiscriminately affect rapidly dividing cells, newer antineoplastic agents such as targeted therapies and immunotherapies are associated with thyroid dysfunction. These include tyrosine kinase inhibitors, bexarotene, radioiodine-based cancer therapies, denileukin diftitox, alemtuzumab, interferon-?, interleukin-2, ipilimumab, tremelimumab, thalidomide, and lenalidomide. Primary hypothyroidism is the most common side effect, although thyrotoxicosis and effects on thyroid-stimulating hormone secretion and thyroid hormone metabolism have also been described. Most agents cause thyroid dysfunction in 20%-50% of patients, although some have even higher rates. Despite this, physicians may overlook drug-induced thyroid dysfunction because of the complexity of the clinical picture in the cancer patient. Symptoms of hypothyroidism, such as fatigue, weakness, depression, memory loss, cold intolerance, and cardiovascular effects, may be incorrectly attributed to the primary disease or to the antineoplastic agent. Underdiagnosis of thyroid dysfunction can have important consequences for cancer patient management. At a minimum, the symptoms will adversely affect the patient's quality of life. Alternatively, such symptoms can lead to dose reductions of potentially life-saving therapies. Hypothyroidism can also alter the kinetics and clearance of medications, which may lead to undesirable side effects. Thyrotoxicosis can be mistaken for sepsis or a nonendocrinologic drug side effect. In some patients, thyroid disease may indicate a higher likelihood of tumor response to the agent. Both hypothyroidism and thyrotoxicosis are easily diagnosed with inexpensive and specific tests. In many patients, particularly those with hypothyroidism, the treatment is straightforward. We therefore recommend routine testing for thyroid abnormalities in patients receiving these antineoplastic agents. PMID:22010182
Hamnvik, Ole-Petter Riksfjord; Larsen, P Reed; Marqusee, Ellen
Thyroid Dysfunction from Antineoplastic Agents
Unlike cytotoxic agents that indiscriminately affect rapidly dividing cells, newer antineoplastic agents such as targeted therapies and immunotherapies are associated with thyroid dysfunction. These include tyrosine kinase inhibitors, bexarotene, radioiodine-based cancer therapies, denileukin diftitox, alemtuzumab, interferon-?, interleukin-2, ipilimumab, tremelimumab, thalidomide, and lenalidomide. Primary hypothyroidism is the most common side effect, although thyrotoxicosis and effects on thyroid-stimulating hormone secretion and thyroid hormone metabolism have also been described. Most agents cause thyroid dysfunction in 20%�50% of patients, although some have even higher rates. Despite this, physicians may overlook drug-induced thyroid dysfunction because of the complexity of the clinical picture in the cancer patient. Symptoms of hypothyroidism, such as fatigue, weakness, depression, memory loss, cold intolerance, and cardiovascular effects, may be incorrectly attributed to the primary disease or to the antineoplastic agent. Underdiagnosis of thyroid dysfunction can have important consequences for cancer patient management. At a minimum, the symptoms will adversely affect the patient�s quality of life. Alternatively, such symptoms can lead to dose reductions of potentially life-saving therapies. Hypothyroidism can also alter the kinetics and clearance of medications, which may lead to undesirable side effects. Thyrotoxicosis can be mistaken for sepsis or a nonendocrinologic drug side effect. In some patients, thyroid disease may indicate a higher likelihood of tumor response to the agent. Both hypothyroidism and thyrotoxicosis are easily diagnosed with inexpensive and specific tests. In many patients, particularly those with hypothyroidism, the treatment is straightforward. We therefore recommend routine testing for thyroid abnormalities in patients receiving these antineoplastic agents.
Larsen, P. Reed; Marqusee, Ellen
Intelligent agent software for medicine.
An important trend for the future of health technology will be the increasing use of intelligent agent software for medical applications. As the complexity of situations faced by both patients and health care providers grows, conventional interfaces that rely on users to manually transfer data and manually perform each problem-solving step, won't be able to keep up. This article describes how software agents that incorporate learning, personalization, proactivity, context-sensitivity and collaboration will lead to a new generation of medical applications that will streamline user interfaces and enable more sophisticated communication and problem-solving. PMID:12026141
Lieberman, Henry; Mason, Cindy
Teratogenesis associated with antibipolar agents
Objective��To review the teratogenic effects associated with the use of Food and Drug Administration-approved agents for bipolar disorder.\\u000a \\u000a \\u000a \\u000a Methods��A PubMed search of all English language articles published from January 1966 to December 2008 was conducted. The key search\\u000a terms included all major bipolar agents, cross-referenced with: teratogenicity, teratogen, safety, pregnancy, fetus, bipolar\\u000a disorder, and malformation. The search was augmented with
Ha T. T. Nguyen; Verinder Sharma; Roger S. McIntyre
EMAA: An Extendable Mobile Agent Architecture
The Extendable Mobile Agent Architecture (EMAA) is a new agent architecture specification that aids in the development of an agent system. The architecture's com- ponent design that has layers of abstraction, providing a generic system. EMAA provides a framework for autono- mous asynchronous mobile software agents to migrate among computing nodes in a network and exploit the resources at those
Russell P. Lentini; Goutham P. Rao; Jon N. Thies; Jennifer Kay
Agent Communication Languages: The Current Landscape
this article---suggest a paradigm for software developmentthat emphasizes autonomy both at design timeand runtime, adaptivity, and cooperation. Thisapproach seems appealing in a world of distributed,heterogeneous systems. Languagesfor communicating agents promise to play therole that natural languages played for theirhuman counterparts. An agent communicationlanguage that allows agents to interactwhile hiding the details of their internal workingswill result in agent communities...
Yannis Labrou; Tim Finin; Yun Peng
Mobile Database Agents for Building Data Warehouses
Agent technology has a number of characteristics that make it well suited for automating information processing tasks and information retrieval. In this paper', we propose a pragmatic approach for appbing mobile agent technology within distributed database management systems (DBMSs). The developed agent environment is based on the Oracle DBMS. It dffers from other agent platforms (e.g. Aglets, Voyager) in its
Edgar Weippl; Josef Altmann; Wolfgang Essmayr
Bali: A Live Desktop for Mobile Agents
As one of the tools for our mobile agent system, Aglets, we developed a desktop-like visual shell, called Bali, to allow natural and intuitive handling of mobile agents. By nature however, mobile agents are autonomous programs. The speed at which an agent executes its own program is very fast in comparison with the speed at which humans operate. Therefore, it
Yoshiaki Mima
Understanding intelligent agents: analysis and synthesis
Current views of intelligent agent technologies are reviewed with respect to (a) their general cognitive capabilities and (b) the classic Belief-Desire-Intention (BDI) model. A benchmark agent model is developed as a basis for analyzing and comparing agent systems. PROforma is an agent technology that has grown out of work in modeling medical expertise and the benchmark is used to carry
John Fox; Martin Beveridge; David Glasspool
From Stakeholder Intentions to Agent Capabilities
Agents behavior at run time is influenced by the environment within which they operate, so designing agents able to behave in an ef- fective way should benefit from a deep knowledge of that envi- ronment, including the stakeholders who have specific needs and expectations from the agents being designed. The specification of agents behavior is typically addressed during detail design,
Loris Penserini; Anna Perini; Angelo Susi; John Mylopoulos
Mole � Concepts of a mobile agent system
Due to its salient properties, mobile agent technology has received a rapidly growing attention over the last few years. Many developments of mobile agent systems are under way in both academic and industrial environments. In addition, there are already various efforts to standardize mobile agent facilities and architectures. Mole is the first mobile agent system that has been developed in
J. Baumann; F. Hohl; K. Rothermel; M. Stra�er
Design issues in mobile agent programming systems
The article discusses system-level issues and agent programming requirements that arise in the design of mobile agent systems. The authors describe several mobile agent systems to illustrate different approaches designers have taken in addressing these challenges. The following areas are discussed: agent mobility, naming, security issues, privacy and integrity, authentication, authorization and access control, metering and charging mechanisms, programming primitives,
Connection Management using Adaptive Mobile Agents
This paper describes how adaptive mobile agents can be used to solve connection management problems in Telecommunications using a parallel, distributed process. These agents have behavior that is inspired by the foraging activities of ants, with each agent capable of simple actions. Problem solving is distributed and arises as a consequence of the self-organization of a collection of agents, or
Tony White; Bernard Pagurek; Franz Oppacher
Mobile agent security based on payment
Mobile agents are autonomous entities that handle tasks for their owner. Agents act on their own by reacting to changes and by planning their course of action. These agents can move from one server to another. In the future, agents will also be supplied with real money in some form to pay for resources or services.In this paper we discuss
Michael Sonntag; Rudolf H�rmanseder
Augmenting agent knowledge bases with OWL ontologies
The use of software agents, viewed as conditioned sets of automatic functions, has become a common and important tool in modern software engineering. Intelligent software agents, are agents that contain some model of the environment that includes a representation of goals desirable to the agent, and that are able to reason about the actual situation and determine some appropriate course
Douglas Holmes; Richard Stocking
Layered Learning in Multi-Agent Systems.
Multi-agent systems in complex, real-time domains require agents to act effectively both autonomously and as part of a team. This dissertation addresses multi-agent systems consisting of teams of autonomous agents acting in real-time, noisy, collaborative...
P. H. Stone
Deploying a personalized time management agent
We report on our ongoing practical experience in designing, im- plementing, and deploying PTIME, a personalized agent for time management and meeting scheduling in an open, multi-agent envi- ronment. In developing PTIME as part of a larger assistive agent called CALO, we have faced numerous challenges, including us- ability, multi-agent coordination, scalable constraint reasoning, ro- bust execution, and unobtrusive learning.
Pauline Berry; Bart Peintner; Ken Conley; Melinda T. Gervasio; Tom�s E. Uribe; Neil Yorke-smith
Building Adaptive Autonomous Agents for Adversarial Domains
This paper presents a methodology, called CAPTAIN, to build adaptive agents in an integrated framework that facilitates both building agents through knowledge elicitation and interactive apprenticeship learning from subject matter experts, and making these agents adapt and improve during their normal use through autonomous learning. Such an automated adaptive agent consists of an adversarial planner and a muitistrategy learner. CAPTAIN
Gheorghe Tecuci I; Michael R. Hieb; David Hille; J. Mark Pullen
Limiting Deception in Groups of Social Agents
In open environments there is no central control over agent behaviors. On the contrary,agents in such systems can be assumed to be primarily driven by self interests.Under the assumption that agents remain in the system for significant time periods, orthat the agent composition changes only slowly, we have previously presented a prescriptivestrategy for promoting and sustaining cooperation in the group.
Anish Biswas; Sandip Sen; Sandip Debnath
D'Agents: Security in a Multiple-Language, Mobile-Agent System
Mobile-agent systems must address three security issues: pro- tecting an individual machine, protecting a group of machines, and pro- tecting an agent. In this chapter, we discuss these three issues in the context of D'Agents, a mobile-agent system whose agents can be writ- ten in Tcl, Java and Scheme. (D'Agents was formerly known as Agent Tcl.) First we discuss mechanisms
Robert S. Gray; David Kotz; George Cybenko; Daniela Rus
Limonene and tetrahydrofurfuryl alcohol cleaning agent
The present invention is a tetrahydrofurfuryl alcohol and limonene cleaning agent and method for formulating and/or using the cleaning agent. This cleaning agent effectively removes both polar and nonpolar contaminants from various electrical and mechanical parts and is readily used without surfactants, thereby reducing the need for additional cleaning operations. The cleaning agent is warm water rinsable without the use of surfactants. The cleaning agent can be azeotropic, enhancing ease of use in cleaning operations and ease of recycling.
Bohnert, G.W.; Carter, R.D.; Hand, T.E.; Powers, M.T.
The present invention is a tetrahydrofurfuryl alcohol and limonene or terpineol cleaning agent and method for formulating and/or using the cleaning agent. This cleaning agent effectively removes both polar and nonpolar contaminants from various electrical and mechanical parts and is readily used without surfactants, thereby reducing the need for additional cleaning operations. The cleaning agent is warm water rinsable without the use of surfactants. The cleaning agent can be azeotropic, enhancing ease of use in cleaning operations and ease of recycling.
Small molecule cyclin D1 ablative agents
Cyclin D1 ablative agents and methods of using these agents in the treatment of cancers, and particularly breast cancer. Also provided are methods of treating cancer, the method comprising administering a therapeutically effective amount of one of the cyclin D1 ablative agents described herein to a subject in need of such treatment. Also provided are methods of treating cancers comprising using the cyclin D1 ablative agents described herein in combination therapies with existing chemotherapeutic agents.
Agents in bioinformatics, computational and systems biology
The adoption of agent technologies and multi-agent systems constitutes an emerging area in bioinformatics. In this article, we report on the activity of the Working Group on Agents in Bioinformatics (BIOAGENTS) founded during the first AgentLink III Technical Forum meeting on the 2nd of July, 2004, in Rome. The meeting provided an opportunity for seeding collaborations between the agent and
Emanuela Merelli; Giuliano Armano; Nicola Cannata; Flavio Corradini; Mark D'inverno; Andreas Doms; Phillip W. Lord; Andrew Martin; Luciano Milanesi; Steffen M�ller; Michael Schroeder; Michael Luck
Anti-Clotting Agents Explained
... survivors, and it helps to understand them. Antiplatelets Blood platelets are actually fragments of cells � meaning they don� ... ability to round up �help� to form a blood clot becomes potentially life-threatening. Anti platelet agents, including aspirin , clopidogrel, dipyridamole and ticlopidine, work ...
Antifibrinolytic agents in subarachnoid haemorrhage
For many years clinicians have used antifibrinolytic agents to try to reduce rebleeding after subarachnoid haemorrhage. Early studies of their effectiveness produced conflicting results. This paper re-evaluates the available trials and considers benefits in the light of potential complications. Present evidence conclusively demonstrates that epsilon-aminocaproic acid and tranexamic acid administered in standard dosage, reduce the risk of rebleeding but, as
K. W. Lindsay
Making Complex Articulated Agents Dance
We discuss the tradeoffs involved in control of complex articulated agents, and present three implemented controllers for a complex task: a physically-based humanoid torso dancing the Macarena. The three controllers are drawn from animation, biological models, and robotics, and illustrate the issues of joint-space vs. Cartesian space task specification and implementation. We evaluate the controllers along several qualitative and quantitative
Maja J. Matari?; Victor B. Zordan; Matthew M. Williamson
Nucleotide cleaving agents and method
The present invention provides a unique series of nucleotide cleaving agents and a method for cleaving a nucleotide sequence, whether single-stranded or double-stranded DNA or RNA, using and a cationic metal complex having at least one polydentate ligand to cleave the nucleotide sequence phosphate backbone to yield a hydroxyl end and a phosphate end.
Que, Jr., Lawrence (Roseville, MN); Hanson, Richard S. (Falcon Heights, MN); Schnaith, Leah M. T. (Redwing, MN)
Voter models with contrarian agents
In the voter and many other opinion formation models, agents are assumed to behave as congregators (also called the conformists); they are attracted to the opinions of others. In this study I investigate linear extensions of the voter model with contrarian agents. An agent is either congregator or contrarian and assumes a binary opinion. I investigate three models that differ in the behavior of the contrarian toward other agents. In model 1, contrarians mimic the opinions of other contrarians and oppose (i.e., try to select the opinion opposite to) those of congregators. In model 2, contrarians mimic the opinions of congregators and oppose those of other contrarians. In model 3, contrarians oppose anybody. In all models, congregators are assumed to like anybody. I show that even a small number of contrarians prohibits the consensus in the entire population to be reached in all three models. I also obtain the equilibrium distributions using the van Kampen small-fluctuation approximation and the Fokker-Planck equation for the case of many contrarians and a single contrarian, respectively. I show that the fluctuation around the symmetric coexistence equilibrium is much larger in model 2 than in models 1 and 3 when contrarians are rare.
Masuda, Naoki
Agents and the Semantic Web
This article offers a few pointers to this emerging area and shows how the ontology languages of the Semantic Web can lead directly to more powerful agent-based approaches---that is, to the realization of my colleague's "science fiction " vision.
James A. Hendler
An inactive pore-forming agent is revealed which is activated to lytic function by a condition such as pH, light, heat, reducing potential, or metal ion concentration, or substance such as a protease, at the surface of a cell. 30 figs.
Bayley, H.; Walker, B.J.; Chang, C.Y.; Niblack, B.; Panchal, R.
How can irrational agents survive?
When we use the agent-based simulation, we have two aims. One is to find the most effective (rational) strategies for the stochastic situation, and the other is to describe the human behaviour. As we know, it is not always true that mathematically rational solution is equal to human behaviour. Most of early studies did the paper questioner based experiment and
Fumihiko HASHIMOTO
An Autonomous Spacecraft Agent Prototype
. This paper describes the New Millennium Remote Agent (NMRA) architecture for autonomous spacecraft control systems. The architecture supports challenging requirements of the autonomous spacecraft domain not usually addressed in mobile robot architectures, including highly reliable autonomous operations over extended time periods in the presence of tight resource constraints, hard deadlines, limited observability, and concurrent activity. A hybrid architecture, NMRA
Barney Pell; Douglas E. Bernard; Steve A. Chien; Erann Gat; Nicola Muscettola; P. Pandurang Nayak; Michael D. Wagner; Brian C. Williams
An autonomous spacecraft agent prototype
. This paper describes the New Millennium Remote Agent (NMRA) architecture for autonomousspacecraft control systems. The architecture supports challenging requirements of the autonomousspacecraft domain not usually addressed in mobile robot architectures, including highly reliableautonomous operations over extended time periods in the presence of tight resource constraints, harddeadlines, limited observability, and concurrent activity. A hybrid architecture, NMRA integrates traditional...
Applications of Agent Based Simulation
This paper provides a survey and analysis of applications of Agent Based Simulation (ABS). A framework for describing and assessing the appli- cations is presented and systematically applied. A general conclusion from the study is that even if ABS seems a promising approach to many problems in- volving simulation of complex systems of interacting entities, it seems as the full
Paul Davidsson; Johan Holmgren; Hans Kyhlb�ck; Dawit Mengistu; Marie Persson
Exposure to toxic environmental agents.
: Reducing exposure to toxic environmental agents is a critical area of intervention for obstetricians, gynecologists, and other reproductive health care professionals. Patient exposure to toxic environmental chemicals and other stressors is ubiquitous, and preconception and prenatal exposure to toxic environmental agents can have a profound and lasting effect on reproductive health across the life course. Prenatal exposure to certain chemicals has been documented to increase the risk of cancer in childhood; adult male exposure to pesticides is linked to altered semen quality, sterility, and prostate cancer; and postnatal exposure to some pesticides can interfere with all developmental stages of reproductive function in adult females, including puberty, menstruation and ovulation, fertility and fecundity, and menopause. Many environmental factors harmful to reproductive health disproportionately affect vulnerable and underserved populations, which leaves some populations, including underserved women, more vulnerable to adverse reproductive health effects than other populations. The evidence that links exposure to toxic environmental agents and adverse reproductive and developmental health outcomes is sufficiently robust, and the American College of Obstetricians and Gynecologists and the American Society for Reproductive Medicine join leading scientists and other clinical practitioners in calling for timely action to identify and reduce exposure to toxic environmental agents while addressing the consequences of such exposure. PMID:24084567
Reducing exposure to toxic environmental agents is a critical area of intervention for obstetricians, gynecologists, and other reproductive health care professionals. Patient exposure to toxic environmental chemicals and other stressors is ubiquitous, and preconception and prenatal exposure to toxic environmental agents can have a profound and lasting effect on reproductive health across the life course.Prenatal exposure to certain chemicals has been documented to increase the risk of cancer in childhood; adult male exposure to pesticides is linked to altered semen quality, sterility, and prostate cancer; and postnatal exposure to some pesticides can interfere with all developmental stages of reproductive function in adult females, including puberty, menstruation and ovulation, fertility and fecundity, and menopause. Many environmental factors harmful to reproductive health disproportionately affect vulnerable and underserved populations,which leaves some populations, including underserved women, more vulnerable to adverse reproductive health effects than other populations. The evidence that links exposure to toxic environmental agents and adverse reproductive and developmental health outcomes is sufficiently robust, and the American College of Obstetricians and Gynecologists and the American Society for Reproductive Medicine join leading scientists and other clinical practitioners in calling for timely action to identify and reduce exposure to toxic environmental agents while addressing the consequences of such exposure. PMID:24070500
Is it an agent or just a program?: A taxonomy for autonomous agents
Abstract The advent of software agents gave rise to much discussion of just what such an agent is, and of how they differ from programs in general. Here we propose a formal definition of an autonomous agent which clearly distinguishes a software agent from just any program. We also offer the beginnings of a natural kinds taxonomyo f autonomous agents,
Stan Franklin
Is it an Agent, or Just a Program?: A Taxonomy for Autonomous Agents
The advent of software agents gave rise to much discussion of just what such an agent is, and of how they differ from programs in general. Here we propose a formal definition of an autonomous agent which clearly distinguishes a software agent from just any program. We also offer the beginnings of a natural kinds taxonomy of autonomous agents, and
Stan Franklin; Arthur C. Graesser
Software for Automation of Real-Time Agents, Version 2
Version 2 of Closed Loop Execution and Recovery (CLEaR) has been developed. CLEaR is an artificial intelligence computer program for use in planning and execution of actions of autonomous agents, including, for example, Deep Space Network (DSN) antenna ground stations, robotic exploratory ground vehicles (rovers), robotic aircraft (UAVs), and robotic spacecraft. CLEaR automates the generation and execution of command sequences, monitoring the sequence execution, and modifying the command sequence in response to execution deviations and failures as well as new goals for the agent to achieve. The development of CLEaR has focused on the unification of planning and execution to increase the ability of the autonomous agent to perform under tight resource and time constraints coupled with uncertainty in how much of resources and time will be required to perform a task. This unification is realized by extending the traditional three-tier robotic control architecture by increasing the interaction between the software components that perform deliberation and reactive functions. The increase in interaction reduces the need to replan, enables earlier detection of the need to replan, and enables replanning to occur before an agent enters a state of failure.
Fisher, Forest; Estlin, Tara; Gaines, Daniel; Schaffer, Steve; Chouinard, Caroline; Engelhardt, Barbara; Wilklow, Colette; Mutz, Darren; Knight, Russell; Rabideau, Gregg; Chien, Steve; Simmons, Reid; Apfelbaum, David
Swarm autonomic agents with self-destruct capability
Systems, methods and apparatus are provided through which in some embodiments an autonomic entity manages a system by generating one or more stay alive signals based on the functioning status and operating state of the system. In some embodiments, an evolvable synthetic neural system is operably coupled to one or more evolvable synthetic neural systems in a hierarchy. The evolvable neural interface receives and generates heartbeat monitor signals and pulse monitor signals that are used to generate a stay alive signal that is used to manage the operations of the synthetic neural system. In another embodiment an asynchronous Alice signal (Autonomic license) requiring valid credentials of an anonymous autonomous agent is initiated. An unsatisfactory Alice exchange may lead to self-destruction of the anonymous autonomous agent for self-protection.
Hinchey, Michael G. (Inventor); Sterritt, Roy (Inventor)
Rapid biological agent identification by surface-enhanced Raman spectroscopy
The Chemical Weapons Convention prohibits the development, production, stockpiling, and use of warfare agents (chemical and biological), and requires their destruction. Yet their use persists and has been included in the terrorist's arsenal. Currently, a number of analytical methods are being developed to perform rapid measurements of trace agents to ensure treaty compliance, as well as safe environments for military personal and the public at large. We have been investigating the ability of surface-enhanced Raman spectroscopy to detect bacterial nucleic acid-base pairs with sufficient sensitivity and selectivity to eliminate the need for enumeration used in polymerase chain reactions and culture growth, required by other measurement techniques. The design of a small volume, fiber optic coupled, electrolytic sample cell is presented along with analysis of DNA and RNA separated from non-toxic bacteria.
Farquharson, Stuart; Smith, Wayne W.; Elliott, Susan; Sperry, Jay F.
Agent-based models in translational systems biology
Effective translational methodologies for knowledge representation are needed in order to make strides against the constellation of diseases that affect the world today. These diseases are defined by their mechanistic complexity, redundancy, and nonlinearity. Translational systems biology aims to harness the power of computational simulation to streamline drug/device design, simulate clinical trials, and eventually to predict the effects of drugs on individuals. The ability of agent-based modeling to encompass multiple scales of biological process as well as spatial considerations, coupled with an intuitive modeling paradigm, suggests that this modeling framework is well suited for translational systems biology. This review describes agent-based modeling and gives examples of its translational applications in the context of acute inflammation and wound healing.
An, Gary; Mi, Qi; Dutta-Moscato, Joyeeta; Vodovotz, Yoram
Impact of hypoglycemic agents on myocardial ischemic preconditioning
Murry et al in 1986 discovered the intrinsic mechanism of profound protection called ischemic preconditioning. The complex cellular signaling cascades underlying this phenomenon remain controversial and are only partially understood. However, evidence suggests that adenosine, released during the initial ischemic insult, activates a variety of G protein-coupled agonists, such as opioids, bradykinin, and catecholamines, resulting in the activation of protein kinases, especially protein kinase C (PKC). This leads to the translocation of PKC from the cytoplasm to the sarcolemma, where it stimulates the opening of the ATP-sensitive K+ channel, which confers resistance to ischemia. It is known that a range of different hypoglycemic agents that activate the same signaling cascades at various cellular levels can interfere with protection from ischemic preconditioning. This review examines the effects of several hypoglycemic agents on myocardial ischemic preconditioning in animal studies and clinical trials.
Rahmi Garcia, Rosa Maria; Rezende, Paulo Cury; Hueb, Whady
Software agents in molecular computational biology.
Progress made in applying agent systems to molecular computational biology is reviewed and strategies by which to exploit agent technology to greater advantage are investigated. Communities of software agents could play an important role in helping genome scientists design reagents for future research. The advent of genome sequencing in cattle and swine increases the complexity of data analysis required to conduct research in livestock genomics. Databases are always expanding and semantic differences among data are common. Agent platforms have been developed to deal with generic issues such as agent communication, life cycle management and advertisement of services (white and yellow pages). This frees computational biologists from the drudgery of having to re-invent the wheel on these common chores, giving them more time to focus on biology and bioinformatics. Agent platforms that comply with the Foundation for Intelligent Physical Agents (FIPA) standards are able to interoperate. In other words, agents developed on different platforms can communicate and cooperate with one another if domain-specific higher-level communication protocol details are agreed upon between different agent developers. Many software agent platforms are peer-to-peer, which means that even if some of the agents and data repositories are temporarily unavailable, a subset of the goals of the system can still be met. Past use of software agents in bioinformatics indicates that an agent approach should prove fruitful. Examination of current problems in bioinformatics indicates that existing agent platforms should be adaptable to novel situations. PMID:16420735
Keele, John W; Wray, James E
Centrifugal elastic coupling
The coupling according to the invention comprises two members with supporting elements and is provided with an elastic ring interacting with the supporting elements. According to the invention, one member is made in the form of a hub with arms and the other member comprises a hub with a rim embracing the elastic ring and the former member with arms. The supporting elements, according to the invention, are secured to the arms and to the inner surface of the ring within the limits of its depth. The coupling of the invention is intended to stabilize rotation when transmitting high speeds and torques as well as to compensate for misalignments of shafts.
Coupled moderator neutronics
Optimizing the neutronic performance of a coupled-moderator system for a Long-Pulse Spallation Source is a new and challenging area for the spallation target-system designer. For optimal performance of a neutron source, it is essential to have good communication with instrument scientists to obtain proper design criteria and continued interaction with mechanical, thermal-hydraulic, and materials engineers to attain a practical design. A good comprehension of the basics of coupled-moderator neutronics will aid in the proper design of a target system for a Long-Pulse Spallation Source.
Russell, G.J.; Pitcher, E.J.; Ferguson, P.D. [Los Alamos National Lab., CA (United States). Manuel Lujan Jr. Neutron Scattering Center
Strong coupling Kondo superconductors
A strong coupling formulation of the two approximations for Kondo superconductors - the M�ller-Hartmann and Zittartz (MHZ) and the Matsuura, Ichinose and Nagaoka (MIN) approach - reveals that the effect of Kondo impurities is overestimated by a factor of at least 1/(1 + ?) because both are based on the BCS theory. A comparison of the results of a strong coupling calculation with experimental data of the system ( La, Ce) and (La 1- x-y, Ce x)Y y proves that the ratio TK/ Tc0 is to be increased significantly in order to achieve agreement between theory and experiment.
Schachinger, E.; Wunder, R.
Coupled Transport Protein Systems
This set of animated lessons provides examples of how transport proteins interact in coupled systems to produce physiologic effects. The gastric pumps animation depicts the secretion of hydrochloric acid into the gastric lumen. The animation called glucose absorption depicts glucose absorption by intestinal epithelial cells. The CFTR animation explains how the cystic fibrosis conductance transmembrane regulator (CFTR) functions as a key component of a coupled system of transport proteins that clears the pulmonary system of mucus and inhaled particulates. These animations serve as valuable resources for any collegiate-level course that describes these processes. Courses that might use them include introductory biology, biochemistry, biophysics, cell biology, pharmacology, and physiology.
Jack D. Thatcher (Lewisburg;West Virginia School of Osteopathic Medicine REV)
Coupled transport protein systems.
This set of animated lessons provides examples of how transport proteins interact in coupled systems to produce physiologic effects. The gastric pumps animation depicts the secretion of hydrochloric acid into the gastric lumen. The animation called glucose absorption depicts glucose absorption by intestinal epithelial cells. The CFTR animation explains how the cystic fibrosis conductance transmembrane regulator (CFTR) functions as a key component of a coupled system of transport proteins that clears the pulmonary system of mucus and inhaled particulates. These animations serve as valuable resources for any collegiate-level course that describes these processes. Courses that might use them include introductory biology, biochemistry, biophysics, cell biology, pharmacology, and physiology. PMID:23592844
Thatcher, Jack D
Innovative agents in cancer prevention.
There are many facets to cancer prevention: a good diet, weight control and physical activity, a healthy environment, avoidance of carcinogens such as those in tobacco smoke, and screening of populations at risk to allow early detection. But there is also the possibility of using drugs or naturally occurring compounds to prevent initiation of, or to suppress, tumour growth. Only a few such agents have been used to date in the clinic with any success, and these include non-steroidal anti-inflammatory drugs for colon, finasteride for prostate and tamoxifen or raloxifene for breast tumours. An ideal chemopreventive agent would restore normal growth control to a preneoplastic or cancerous cell population by modifying aberrant signalling pathways or inducing apoptosis (or both) in cells beyond repair. Characteristics for such an agent include selectivity for damaged or transformed cells, good bioavailability and more than one mechanism of action to foil redundancy or crosstalk in signalling pathways. As more research effort is being targeted towards this area, the distinction between chemotherapeutic and chemopreventive agents is blurring. Chemotherapeutic drugs are now being designed to target over- or under-active signalling molecules within cancer cells, a philosophy which is just as relevant in chemoprevention. Development of dietary agents is particularly attractive because of our long-standing exposure to them, their relative lack of toxicity, and encouraging indications from epidemiology. The carcinogenic process relies on the cell's ability to proliferate abnormally, evade apoptosis, induce angiogenesis and metastasise to distant sites. In vitro studies with a number of different diet-derived compounds suggest that there are molecules capable of modulating each of these aspects of tumour growth. However, on the negative side many of them have rather poor bioavailability. The challenge is to uncover their multiple mechanisms of action in order to predict their efficacy, to learn how to use them effectively in combination, and in some cases to redesign them to improve potency or bioavailability. These ideas are illustrated by dietary agents such as indole-3-carbinol (I3C), epigallocatechin gallate (EGCG), curcumin and resveratrol, all of which appear to have a number of different molecular targets, impinging on several signalling pathways. Ultimately it may be possible not only to suppress tumours and to extend quality of life by administering appropriate diet-derived molecules, but also to refine the definition of a cancer chemopreventive diet. PMID:15648195
Manson, Margaret M; Farmer, Peter B; Gescher, Andreas; Steward, William P
Coevolutionary networks of reinforcement-learning agents
This paper presents a model of network formation in repeated games where the players adapt their strategies and network ties simultaneously using a simple reinforcement-learning scheme. It is demonstrated that the coevolutionary dynamics of such systems can be described via coupled replicator equations. We provide a comprehensive analysis for three-player two-action games, which is the minimum system size with nontrivial structural dynamics. In particular, we characterize the Nash equilibria (NE) in such games and examine the local stability of the rest points corresponding to those equilibria. We also study general n-player networks via both simulations and analytical methods and find that, in the absence of exploration, the stable equilibria consist of star motifs as the main building blocks of the network. Furthermore, in all stable equilibria the agents play pure strategies, even when the game allows mixed NE. Finally, we study the impact of exploration on learning outcomes and observe that there is a critical exploration rate above which the symmetric and uniformly connected network topology becomes stable.
Kianercy, Ardeshir; Galstyan, Aram
Coevolutionary networks of reinforcement-learning agents.
This paper presents a model of network formation in repeated games where the players adapt their strategies and network ties simultaneously using a simple reinforcement-learning scheme. It is demonstrated that the coevolutionary dynamics of such systems can be described via coupled replicator equations. We provide a comprehensive analysis for three-player two-action games, which is the minimum system size with nontrivial structural dynamics. In particular, we characterize the Nash equilibria (NE) in such games and examine the local stability of the rest points corresponding to those equilibria. We also study general n-player networks via both simulations and analytical methods and find that, in the absence of exploration, the stable equilibria consist of star motifs as the main building blocks of the network. Furthermore, in all stable equilibria the agents play pure strategies, even when the game allows mixed NE. Finally, we study the impact of exploration on learning outcomes and observe that there is a critical exploration rate above which the symmetric and uniformly connected network topology becomes stable. PMID:23944526
Solubilization of therapeutic agents in micellar nanomedicines.
We use atomistic molecular dynamics simulations to reveal the binding mechanisms of therapeutic agents in PEG-ylated micellar nanocarriers (SSM). In our experiments, SSM in buffer solutions can solubilize either ?11 small bexarotene molecules or ?6 (2 in low ionic strength buffer) human vasoactive intestinal peptide (VIP) molecules. Free energy calculations reveal that molecules of the poorly water-soluble drug bexarotene can reside at the micellar ionic interface of the PEG corona, with their polar ends pointing out. Alternatively, they can reside in the alkane core center, where several bexarotene molecules can self-stabilize by forming a cluster held together by a network of hydrogen bonds. We also show that highly charged molecules, such as VIP, can be stabilized at the SSM ionic interface by Coulombic coupling between their positively charged residues and the negatively charged phosphate headgroups of the lipids. The obtained results illustrate that atomistic simulations can reveal drug solubilization character in nanocarriers and be used in efficient optimization of novel nanomedicines. PMID:24283508
Vukovi?, Lela; Madriaga, Antonett; Kuzmis, Antonina; Banerjee, Amrita; Tang, Alan; Tao, Kevin; Shah, Neil; Kr�l, Petr; Onyuksel, Hayat
Neuroprotective "agents" in surgery. Secret "agent" man, or common "agent" machine?
The search for clinically-effective neuroprotective agents has received enormous support in recent years--an estimated $200 million by pharmaceutical companies on clinical trials for traumatic brain injury alone. At the same time, the pathophysiology of brain injury has proved increasingly complex, rendering the likelihood of a single agent "magic bullet" even more remote. On the other hand, great progress continues with technology that makes surgery less invasive and less risky. One example is the application of endovascular techniques to treat coronary artery stenosis, where both the invasiveness of sternotomy and the significant neurological complication rate (due to microemboli showering the cerebral vasculature) can be eliminated. In this paper we review aspects of intraoperative neuroprotection both present and future. Explanations for the slow progress on pharmacologic neuroprotection during surgery are presented. Examples of technical advances that have had great impact on neuroprotection during surgery are given both from coronary artery stenosis surgery and from surgery for Parkinson's disease. To date, the progress in neuroprotection resulting from such technical advances is an order of magnitude greater than that resulting from pharmacologic agents used during surgery. The progress over the last 20 years in guidance during surgery (CT and MRI image-guidance) and in surgical access (endoscopic and endovascular techniques) will soon be complemented by advances in our ability to evaluate biological tissue intraoperatively in real-time. As an example of such technology, the NASA Smart Probe project is considered. In the long run (i.e., in 10 years or more), pharmacologic "agents" aimed at the complex pathophysiology of nervous system injury in man will be the key to true intraoperative neuroprotection. In the near term, however, it is more likely that mundane "agents" based on computers, microsensors, and microeffectors will be the major impetus to improved intraoperative neuroprotection.
Andrews, R. J.
Lateral coupled cavity semiconductor laser
This patent describes a monolithic lateral-coupled laser array comprised of at least two stripe laser cavities of different effective length in close parallel proximity to each other for coupling of radiation. The longer of the stripe laser cavities is cleaved to provide separate parts, and the parts are cleaved coupled to form one strip laser cavity lateral coupled to the
J. Salzman; R. J. Lang; A. Yariv
Chiteki kensaku no tame no agent no chosa. (Survey of agent for intelligent information retrieval).
Development of agent systems has been surveyed, to classify and arrange characteristic functions of the agents, and to grasp the realization situation of these agents in their development. In addition, prospective functions of information retrieval system...
T. Yazawa
Modeling and Visualizing Flow of Chemical Agents Across Complex Terrain
Release of chemical agents across complex terrain presents a real threat to homeland security. Modeling and visualization tools are being developed that capture flow fluid terrain interaction as well as point dispersal downstream flow paths. These analytic tools when coupled with UAV atmospheric observations provide predictive capabilities to allow for rapid emergency response as well as developing a comprehensive preemptive counter-threat evacuation plan. The visualization tools involve high-end computing and massive parallel processing combined with texture mapping. We demonstrate our approach across a mountainous portion of North California under two contrasting meteorological conditions. Animations depicting flow over this geographical location provide immediate assistance in decision support and crisis management.
Kao, David; Kramer, Marc; Chaderjian, Neal
Fostering Multimedia Learning of Science: Exploring the Role of an Animated Agent's Image
Research suggests that students learn better when studying a picture coupled with narration rather than on-screen text in a computer-based multimedia learning environment. Moreover, combining narration with the visual presence of an animated pedagogical agent may also encourage students to process information deeper than narration or on-screen�
Dunsworth, Qi; Atkinson, Robert K.
The research on technology spillover of corporative technology innovation based on multi-agent model
This paper discusses the relationship between technology spillover and the stability of cooperation based on the research of technology component, coupling and evolution. Moreover, this paper suggests an artificial societies using Multi-Agent model. This paper proves that technology spillovers as a cooperative pattern is effective and it also impels the enterprise building the confidence to accelerate the process of innovation.
Fan Jian-ping; Li-Chang-hong; Wu Mei-qin; Liang Jia-hua
Prebiotic condensation reactions in an aqueous medium: A review of condensing agents
Biopolymers are formed by dehydration-type condensation reactions. In aqueous solutions dehydration reactions are very unlikely to happen spontaneously. However, coupling of dehydration-condensation to the hydrolysis of condensing agents could facilitate the synthesis of biopolymers in an aqueous solution. The literature shows that the peptides, nucleosides, nucleotides and oligonucleotides can be formed in this way. A careful study of the literature
Jos�e Hulshof; Cyril Ponnamperuma
Linezolid: an oxazolidinone antimicrobial agent
Background: Linezolid is the first oxazolidinone anti-infective agent marketed in the United States. It is indicated for the treatment of nosocomial pneumonia, complicated skin and skin-structure infections caused by methicillin-sensitive or methicillin-resistant Staphylococcus aureus and other susceptible organisms, and vancomycin-resistant Enterococcus faecium infections. It also is indicated for the treatment of uncomplicated skin and skin-structure infections caused by methicillin-sensitive S
Horatio B. Fung; Harold L. Kirschenbaum; Babatunde O. Ojofeitimi
Analysis of chemical warfare agents
A series of normal aliphatic thiols have been used to derivatise the chemical warfare agents Lewisites I and II (LI and LII) in hydrocarbon matrices. Varying the chain length of the thiol allowed adjustment of derivative tR by 5.9min for Lewisite I and 5.3min for Lewisite II. Linear regression analysis of the chain length of the thiol derivatives of the
Bob Muir; Ben J Slater; David B Cooper; Christopher M Timperley
Mobile agents for adaptive routing
This paper introduces AntNet, a new routing algorithm for telecommunication networks. AntNet is an adaptive, distributed, mobile-agents-based algorithm which was inspired by recent work on the ant colony metaphor. We apply AntNet in a datagram network and compare it with both static and adaptive state-of-the-art routing algorithms. We ran experiments for various paradigmatic temporal and spatial traffic distributions. AntNet showed
Gianni Di Caro; M. Dorigo
Agents' Interaction in Virtual Storytelling
In this paper we describe a fully implemented prototype for interactive storytelling using the Unreal� engine. Using a sit-com like scenario as an example of how the dynamic interactions between agents and\\/or the user dramatise the emerging story. Hierarchical Task Networks (HTNs) are formalised using AND\\/OR graphs, which are used to describe the many possible variations of the story at
Marc Cavazza; Fred Charles; Steven J. Mead
Arsenic compounds as anticancer agents
In this paper the use of arsenic compounds as anticancer agents in clinical trials and in in vitro investigations is reviewed, including the experience at our institute. Treatment of newly diagnosed and relapsed patients with acute promyelocytic leukemia (APL) with arsenic trioxide (As2O3) has been found to result in complete remission (CR) rates of 85-93% when given by intravenous infusion
Zhen-Yi Wang
Novel infectious agents causing uveitis
In any patient with uveitis, an infectious cause should be ruled out first. The differential diagnosis includes multiple well-known\\u000a diseases including herpes, syphilis, toxoplasmosis, tuberculosis, bartonellosis, Lyme disease, and others. However, clinician\\u000a should be aware of emerging infectious agents as potential causes of systemic illness and also intraocular inflammation. Air\\u000a travel, immigration, and globalization of business have overturned traditional pattern
Moncef Khairallah; Soon Phaik Chee; Sivakumar R. Rathinam; Sonia Attia; Venu Nadella
Affective Computing for Future Agents
\\u000a To the extent that future agents will interact with people and with one another via text, speech, and other modes that suggest\\u000a social interaction, they may benefit from having certain skills of social-emotional intelligence, such as the ability to see\\u000a if they have annoyed a person. Already, many animated characters have the ability to express emotion (give the appearance\\u000a of
Rosalind W. Picard
Proarrhythmic Potential of Antimicrobial Agents
Several antiarrhythmic and non-cardiovascular drug therapies including antimicrobial agents have been implicated as the causes\\u000a for QT interval prolongation, torsades de pointes (TdP) ventricular tachycardia and sudden cardiac death. Most of the drugs\\u000a that have been associated with the lengthening of the QT interval or development of TdP can also block the rapidly activating\\u000a component of the delayed rectifier potassium
J. Simk�; A. Csilek; J. Kar�szi; I. L?rincz
Multi-Agent Transport Planning
We discuss a distributed transport planning problem with competitive\\u000aautonomous actors that carry out time-constrained pick-up delivery orders\\u000afrom customers. The agents have to find conflict-free routes to execute a series of orders they have accepted. Hatzack and Nebel [2] were the first to suggest that finding such a conflict-free schedule can be reduced to solving a job shop scheduling
J. Zutt; C. Witteveen
Agent Identification and Preclinical Testing
\\u000a This chapter provides an overview of the preclinical screening assays and animal efficacy testing models currently utilized\\u000a by the drug discovery and development program of the Division of Cancer Prevention (DCP), National Cancer Institute (NCI)\\u000a to identify chemical agents or natural biological products which may be efficacious in preventing human cancers. The first\\u000a step of the drug discovery process involves
James A. Crowell; Cathy J. Holmes
Etiologic role of infectious agents.
A consensus statement found in most peer-reviewed literature on sarcoidosis is that the etiology of sarcoidosis is unknown. It is timely to review whether this statement should be revised. Many infectious agents meet the basic requirements of inducing granulomatous inflammation and immunologic responses consistent with sarcoidosis including oligoclonal expansion of CD4+ T cells, polarized Th1 and possibly Th17 responses, and dysregulated regulatory T-cell function. Studies over the past decade provide increasing and complementary data to implicate a role for infectious agents in sarcoidosis etiology. These studies used different methodologies such as polymerase chain reaction and mass spectrometry to document microbial nucleic acids and proteins in sarcoidosis tissues. Multiple studies report antigen-specific immune responses to specific microbial proteins in sarcoidosis. In aggregate, these studies provide compelling evidence that mycobacteria play a major etiologic role in sarcoidosis in the United States and Europe. Studies from Japan support a role for Propionibacteria as a major etiologic agent in the country. There is controversy over how these (or other) infectious agents cause sarcoidosis. The hypothesis that chronic sarcoidosis is caused by a viable, replicating mycobacterial or other infection has no direct pathologic, microbiologic, or clinical evidence. A novel hypothesis links microbial triggers to a sarcoidosis outcome from the accumulation of aggregated proinflammatory serum amyloid A within granulomas, providing a mechanism for chronic disease in the absence of any viable tissue infection. Further studies are needed to provide more definitive evidence for these competing hypotheses before the statement that the etiology of sarcoidosis is unknown becomes obsolete. PMID:25007081
Chen, Edward S; Moller, David R
Coupled Resonant Pendulums
This site from the Exploratorium provides a demonstration, using everyday materials, of the energy exchange between two coupled pendulums. The site provides a thorough description of how the two pendulums interact and contrasts their motion. The site also describes an easy to find the rate of energy exchange.
Two Coupled Pendula
This site, provided by the University of Nijmegen, presents an applet simulation of a system of two pendula coupled by a spring, along with a "Lecture-room" that provides the theoretical background. The lengths, masses, and initial angles of the pendula can be adjusted. The site produces an animation of their displacements, which facilitates a qualitative explanation of the motion.
Coupling Gammasphere and ORRUBA
The coincident detection of particles and gamma rays allows the study of the structure of exotic nuclei via inverse kinematics reactions using radioactive ion beams and thick targets. We report on the status of the project to couple the highresolution charged-particle detector ORRUBA to Gammasphere, a high-efficiency, high-resolution gamma ray detector.
Ratkiewicz, A.; Cizewski, J. A.; Manning, B. [Department of Physics and Astronomy, Rutgers University, New Brunswick, NJ 08903 (United States); Pain, S. D.; Bardayan, D. W. [Physics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Blackmon, J. C.; Matos, M. [Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803 (United States); Chipps, K. A. [Department of Physics, Colorado School of Mines, Golden, CO 80401 (United States); Hardy, S.; Shand, C. [Department of Physics and Astronomy, Rutgers University, New Brunswick, NJ 08903 and Department of Physics, University of Surrey, Guildford, Surrey, GU2 7XH (United Kingdom); Jones, K. L. [Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996 (United States); Kozub, R. L. [Physics Department, Tennessee Technological University, Cookeville, TN 38505 (United States); Lister, C. J. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 and Department of Physics and Applied Physics, University of Massachusetts Lowell, Lowell, MA 01854 (United States); Peters, W. A. [Oak Ridge Associated Universities, Oak Ridge, TN 37830 (United States); Seweryniak, D. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States)
Coupling of quantum logics
A quantum logic is a couple (L, M), whereL is a logic andM is a quite full set of states onL. A tensor product in the category of quantum logics is defined and a comparison with the definition of free orthodistributive product of orthomodular ? lattices is given. Several physically important cases are treated.
S. Pulmannov�
Patterns of intelligent and mobile agents
1. ABSTRACT Agent systems must have a strong foundation; one approach that has been successfully applied to other kinds of software is patterns. This paper presents a collection of patterns for agents.
Elizabeth A. Kendall; P. V. Murali Krishna; Chirag V. Pathak; C. B. Suresh
Viral Gastroenteritis Agents and Waterborne Disease.
The application of electron microscopic techniques in the study of human gastroenteritis led in the 1970's to the identification of new viral agents that had previously escaped detection by routine cell culture procedures. These agents have been the focus...
F. P. Williams
Facilitators and Mediators for Intelligent Agent Protocols.
This project focuses on the development of and experimentation with a language and protocol intended to support interoperability among intelligent agents in a distributed application. Examples of applications envisioned include intelligent multi-agent des...
T. W. Finin
Toward Agent Programs with Circuit Semantics.
New ideas are presented for computing and organizing actions for autonomous agents in dynamic environments-environments in which the agent's current situation cannot always be accurately discerned and in which the effects of actions cannot always be relia...
N. J. Nilsson
CDC's CHEMPACK Project: Nerve Agent Antidote Storage.
Nerve agent antidotes in the CHEMPACK project were stored at temperatures required by the Food and Drug Administration (FDA), the Centers for Disease Control and Prevention (CDC) implemented procedures to ensure the quality of nerve agent antidotes in the...
Intelligent Agent Architectures: Reactive Planning Testbed
An Integrated Agent Architecture (IAA) is a framework or paradigm for constructing intelligent agents. Intelligent agents are collections of sensors, computers, and effectors that interact with their environments in real time in goal-directed ways. Because of the complexity involved in designing intelligent agents, it has been found useful to approach the construction of agents with some organizing principle, theory, or paradigm that gives shape to the agent's components and structures their relationships. Given the wide variety of approaches being taken in the field, the question naturally arises: Is there a way to compare and evaluate these approaches? The purpose of the present work is to develop common benchmark tasks and evaluation metrics to which intelligent agents, including complex robotic agents, constructed using various architectural approaches can be subjected.
Rosenschein, Stanley J.; Kahn, Philip
Intelligent Agents as Cognitive Tools for Education.
Examines the educational potential for intelligent agents as cognitive tools. Discusses the role of intelligent agents: managing large amounts of information (information overload), serving as a pedagogical expert, and creating programming environments for the learner. (AEF)
Baylor, Amy
Therapeutic Agents and Methods for Cardiovascular Disease.
The present invention provides methods and agents for treating subjects who have or are at risk of developing or having cardiovascular disease. Such agents inhibit binding of myeloperoxidase (MPO) to a molecule comprising the MPO binding site of apolipopr...
M. S. Penn S. L. Hazen
Observation and inverse problems in coupled cell networks
A coupled cell network is a model for many situations such as food webs in ecosystems, cellular metabolism and economic networks. It consists in a directed graph G, each node (or cell) representing an agent of the network and each directed arrow representing which agent acts on which. It yields a system of differential equations \\dot x(t)=f(x(t)) , where the component i of f depends only on the cells xj(t) for which the arrow j ? i exists in G. In this paper, we investigate the observation problems in coupled cell networks: can one deduce the behaviour of the whole network (oscillations, stabilization, etc) by observing only one of the cells? We show that the natural observation properties hold for almost all the interactions f.
Joly, Romain
Secure Itineraries Framework for Mobile Agent Systems
Mobile agent system raises significant security concerns and requires a thorough security framework, with a wide range of\\u000a strategies and mechanisms, for the protection of both agents and agent hosts, against possibly malicious behavior. Researchers\\u000a have identi?ed several security attacks. In general, the behavior of mobile agents is often prescribed by the set of tasks\\u000a represented in an itinerary. The
Rajwinder Singh; Navdeep Kaur; Anil Kumar Sarje
Agents from Functional-Computational Perspective
The contribution sketches a functional-computational typological scale of agents starting form the reactive ones, and puts the family of (at least minimally) conscious agents into the proposed typology. Then it discusses the traditional computational properties of agents according their types, and sketches a way of a rather non-traditional computational characterization of conscious agents using the concept of hyper-computation. The contribution
Jozef Kelemen
Path Planning by Negotiation for Decentralized Agents
This paper presents a real-time path-planning algorithm for decentralized agents, which provides guaranteed collision-free paths for the agents towards their desired destinations. The algorithm is run locally on the agents, which can exchange information using wireless communication. The algorithm is robust with respect to arbitrary delays in the wireless traffic, possible sources being transmission time, error correction, and others. Agents
Oliver Purwin; R. D'Andrea
Participatory, embodied, multi-agent simulation
We will demonstrate the integration of a software-based multi-agent modeling platform with a participatory simulation environment and real-time control over a physical agent (robot). Both real and virtual participants will be able to act as agents in a simulation that will control a physical agent. The backbone of this demonstration is a widely used, freely available, mature modeling platform known
Paulo Blikstein; William Rand; Uri Wilensky
Contextual activation for agent-based simulation
Abstract�When designing agent-based simulation, the choice of a coordination model is a key issue, since one of the diculties,is to link the activation of the agents with their context eciently.,Current solutions sepa- rate the activation phase from the action phase of the agents, and each action phase is based on local agent context analysis which is time-expensive. Moreover, be- cause
Fabien BADEIG; Flavien BALBO; Suzanne PINSON
Agent-based Modeling and Simulation
Agent-based modeling and simulation (ABMS) is a new approach to modeling systems comprised of autonomous, interacting agents. Computational advances have made possible a growing number of agent-based models across a variety of application domains. Applications range from modeling agent behavior in the stock market, supply chains, and consumer markets, to predicting the spread of epidemics, mitigating the threat of bio-warfare,
Charles M. Macal; Michael J. North
Emergent Behavior of Coupled Barrier Island - Resort Systems
Barrier islands are attractive sites for resorts. Natural barrier islands experience beach erosion and island overwash during storms, beach accretion and dune building during inter-storm periods, and migration up the continental shelf as sea level rises. Beach replenishment, artificial dune building, seawalls, jetties and groins have been somewhat effective in protecting resorts against erosion and overwash during storms, but it is unknown how the coupled system will respond to long-term sea level rise. We investigate coupled barrier island - resort systems using an agent-based model with three components: natural barrier islands divided into a series of alongshore cells; resorts controlled by markets for tourism and hotel purchases; and coupling via storm damage to resorts and resort protection by government agents. Modeled barrier islands change by beach erosion, island overwash and inlet cutting during storms, and beach accretion, tidal delta growth and dune and vegetation growth between storms. In the resort hotel market, developer agents build hotels and hotel owning agents purchase them using predictions of future revenue and property appreciation, with the goal of maximizing discounted utility. In the tourism market, hotel owning agents set room rental prices to maximize profit and tourist agents choose vacation destinations maximizing a utility based on beach width, price and word-of-mouth. Government agents build seawalls, groins and jetties, and widen the beach and build up dunes by adding sand to protect resorts from storms, enhance beach quality, and maximize resort revenue. Results indicate that barrier islands and resorts evolve in a coupled manner to resort size saturation, with resorts protected against small-to-intermediate-scale storms under fairly stable sea level. Under extended, rapidly rising sea level, protection measures enhance the effect of large storms, leading to emergent behavior in the form of limit cycles or barrier submergence, depending on the relative rates of resort recovery from storms and sea level rise. The model is applied to Ocean City, Maryland and neighboring undeveloped Assateague Island National Seashore. Supported by the National Science Foundation, Geology and Paleontology Program, and the Andrew W. Mellon Foundation
McNamara, D. E.; Werner, B. T.
Mobile security agents for network traffic analysis
This paper describes the implementation of a distributed agent architecture for intrusion detection and response in networked computers. Unlike conventional intrusion detection systems (IDS), this security system attempts to emulate mechanisms of the natural immune system using Java-based mobile software agents. These security agents monitor multiple levels (packet process, system, and user) of networked computers to determine correlation among the
Dipankar Dasgupta; Hal Brian
Performance management of mobile agent systems
A framework for developing 'mobile agent' systems is described based on Petri net models of design patterns in the Aglets workbench. The models can be automatically configured from Java source programs, and can account for stochastic parameters such as port contention at hosts, agent registration, background workloads and scalability issues, such as bounds on total number of agents that may
Omer F. Rana
A Performance Model for Mobile Agent Systems
A performance model for the interaction of agents in mobile agent systems is presented. Two inter- action models, namely the remote procedure call and the agent migration are considered. Performance mod- els for a single interaction are introduced, which are then used to derive a performance model for a sequence of interactions. This performance model can be used to evaluate
Markus Stra�er; Markus Schwehm
Feasible formations of multi-agent systems
Formations of multi-agent systems, such as satellites and aircraft, require that individual agents satisfy their kinematic equations while constantly maintaining inter-agent constraints. In this paper, we develop a systematic framework for studying formations of multiagent systems. In particular, we consider undirected formations for centralized formations and directed formations for decentralized formations. In each case, we determine differential geometric conditions that
Paulo Tabuada; George J. Pappas; Pedro Lima
International Insurance Traffic with Software Agents
This paper presents a business case on digital cross- border information flo w within a European network of insur- ance companies. Underlying the business case is the multi-agent paradigm. The paper explores a structured approach for designing agent behavior based on the 5 Capabilities (5C) agent model. The central value of the 5C model is the conceptual separation of con-
Chris Van Aart; Kris Van Marcke; Ruurd Pels; Jan Smulders
Software agents in molecular computational biology
Progress made in applying agent systems to molecular computational biology is reviewed and strategies by which to exploit agent technology to greater advantage are investigated. Communities of software agents could play an important role in helping genome scientists design reagents for future research. The advent of genome sequencing in cattle and swine increases the complexity of data analysis required to
John W. Keele; James E. Wray
Using Intelligent Agents To Assist Educators.
This paper begins with background on intelligent agents (software programs built to perform certain specific tasks for the user). A taxonomy that categorizes intelligent agents by the degree of intelligence embedded in the software is presented. Applications of today's intelligent agents are discussed, including specific examples of the following:�
Knode, Steve; Knode, Jon-David W.
BABSy: Basic Agent Framework Billing System
The fast growing field of electronic commerce brings today's applications to their limits. Agents are now being used to further automate the purchase processes. Agents already support many stages of the buying cycle, but currently there is only little agent support for accounting and payment. In this paper we describe the design and implementation of BABSy, an accounting system that
Rupert Rockinger; Hubert Baumeister
Mobile agents in network-centric warfare
This paper describes agent technology and the various ways in which it can be applied to command, control, communications and intelligence in general, and to network-centric warfare in particular. The paper provides a brief overview of agents, their properties, and their advantages. It covers the concept of the current military trend, network-centric warfare. Problems associated with agents are described, including
M. G. Ceruti
DAEDALUS for Agents with Obstructed Perception
Traditional approaches to designing multi-agent systems are offline (in simulation), and assume the presence of a global observer. In the online (real world), there may be no global observer, performance feedback may be delayed or perturbed by noise, agents may only interact with their local neighbors, and only a subset of agents may experience any form of performance feedback. Under
Suranga Hettiarachchi; William M. Spears
Agent-based modeling of complex infrastructures
Complex Adaptive Systems (CAS) can be applied to investigate complex infrastructures and infrastructure interdependencies. The CAS model agents within the Spot Market Agent Research Tool (SMART) and Flexible Agent Simulation Toolkit (FAST) allow investigation of the electric power infrastructure, the natural gas infrastructure and their interdependencies.
North, M. J.
Domain-dependent information gathering agent
A universal agent should be capable of gathering information from arbitrary heterogeneous sites and offer intelligent information services on its own based on information so gathered. We present a domain-dependent agent for information gathering. It can visit an arbitrary domain-related site by observing a user perform the first query. By understanding key concepts of the first query, the agent performs
Aleksander Pivk; Matjaz Gams
Context Aware Personal Agent for Spiritual Exploration
This paper describes a personal agent to assist users in dealing with personal and psycho-spiritual issues. As Internet-based applications move beyond simple information presentation and social networking, the use of agent technology to create a personal, customized, and comforting presence becomes possible. This ability derives from an agent implementation that can offer thousands of years of spiritual and psychological wisdom
Michael R. Neal; d'Armond L. Speers
FIPA agent based network distributed control system
A control system with the capabilities to combine heteregeneous control systems or processes into a uniform homogeneous environment is discussed. This dynamically extensible system is an example of the software system at the agent level of abstraction. This level of abstraction considers agents as atomic entities that communicate to implement the functionality of the control system. Agents engineering aspects are
V. Gyurjyan; D. Abbott; G. Heyes; E. Jastrzembski; C. Timmer; E. Wolin
Letizia: An Agent That Assists Web Browsing
Letizia is a user interface agent that assists a user browsing the World Wide Web. As the user operates a conventional Web browser such as Netscape, the agent tracks user behavior and attempts to anticipate items of interest by doing concurrent, autonomous exploration of links from the user's current position. The agent automates a browsing strategy consisting of a best-first
Henry Lieberman
LEOPARD: a .net based agent architecture
Motivated by recent developments in Category theory and Web Community Discovery, we have developed an experimental platform to design Agent-based Systems. This paper describes why and how the architecture was developed under the Microsoft .Net environment with the Object-Oriented Language C#. The proposed architecture is based on three layers. The .Net C# Agent Infrastructure, that enables agents to live and
Annya R�quil�-Romanczuk; Christine Mingins; Brian Yap; Olivier Constant
Cooperative performance system based on agents
This paper describes a cooperative performance system based on agents. To realize more intimate cooperation, it is necessary for the system to consider the feelings of a user which reflect his personal taste and mental state. We propose a model of cooperation of the agents considering those feelings. In this model, emotional factors of agents are expressed by �mental potential�,
J. Kawabata; N. Saiwaki; S. Nishida
Contrast enhancing agents in ultrasonography: Clinical applications
Introduction: As ultrasound remains a poorly sensitive method, echocontrast agents make a real difference. At least 29 echocontrast agents are currently on trial worldwide; their chemical composition, mechanisms of action and possible clinical applications are different. The state of the art of echocontrast agents is discussed: their established applications, those expected in the near future and finally their hypothetical, ideal
Rodolfo Campani; Fabrizio Calliada; Olivia Bottinelli; Anna Bozzini; Maria Grazia Sommaruga; Ferdinando Draghi; Rizzardo Anguissola
Optimal Sensor Placement for Agent Localization
In this paper we consider deploying a network of static sensors to help an agent navigate in an area. In particular the agent uses range measurements to the sensors to localize itself. We wish to place the sensors in order to provide optimal localization accuracy to the agent. We begin by considering the problem of placing sensors in order to
D. B. Jourdan; N. Roy
Optimal sensor placement for agent localization
Abstract� In this paper we consider deploying a network of static sensors to help an agent navigate in an area. In particular the agent uses range measurements to the sensors to localize itself. We wish to place the sensors in order to provide optimal localization accuracy to the agent. We begin by considering the problem of placing sensors in order
Damien B. Jourdan; Nicholas Roy
New coupled quintessence cosmology
A component of dark energy has been recently proposed to explain the current acceleration of the Universe. Unless some unknown symmetry in Nature prevents or suppresses it, such a field may interact with the pressureless component of dark matter, giving rise to the so-called models of coupled quintessence. In this paper we propose a new cosmological scenario where radiation and baryons are conserved, while the dark energy component is decaying into cold dark matter. The dilution of cold dark matter particles, attenuated with respect to the usual a-3 scaling due to the interacting process, is characterized by a positive parameter ?, whereas the dark energy satisfies the equation of state px=??x (?<0). We carry out a joint statistical analysis involving recent observations from type Ia supernovae, baryon acoustic oscillation peak, and cosmic microwave background shift parameter to check the observational viability of the coupled quintessence scenario here proposed.
Jesus, J. F.; Santos, R. C.; Alcaniz, J. S.; Lima, J. A. S.
A component of dark energy has been recently proposed to explain the current acceleration of the Universe. Unless some unknown symmetry in Nature prevents or suppresses it, such a field may interact with the pressureless component of dark matter, giving rise to the so-called models of coupled quintessence. In this paper we propose a new cosmological scenario where radiation and baryons are conserved, while the dark energy component is decaying into cold dark matter. The dilution of cold dark matter particles, attenuated with respect to the usual a{sup -3} scaling due to the interacting process, is characterized by a positive parameter {epsilon}, whereas the dark energy satisfies the equation of state p{sub x}={omega}{rho}{sub x} ({omega}<0). We carry out a joint statistical analysis involving recent observations from type Ia supernovae, baryon acoustic oscillation peak, and cosmic microwave background shift parameter to check the observational viability of the coupled quintessence scenario here proposed.
Jesus, J. F.; Santos, R. C.; Lima, J. A. S. [Universidade de Sao Paulo, 05508-900, Sao Paulo, SP (Brazil); Alcaniz, J. S. [Observatorio Nacional, 20921-400, Rio de Janeiro-RJ (Brazil); Instituto Nacional de Pesquisas Espaciais/CRN, 59076-740, Natal-RN (Brazil)
A cooling apparatus includes a container filled with a quantity of coolant fluid initially cooled to a solid phase, a cooling loop disposed between a heat load and the container, a pump for circulating a quantity of the same type of coolant fluid in a liquid phase through the cooling loop, and a pair of couplings for communicating the liquid phase coolant fluid into the container in a direct interface with the solid phase coolant fluid.
Lomax, Curtis (inventor); Webbon, Bruce (inventor)
Magnetic coupling device
A quick connect/disconnect coupling apparatus is provided in which a base member is engaged by a locking housing through a series of interengagement pins. The pins maintain the shaft in a locked position. Upon exposure to an appropriately positioned magnetic field, pins are removed a sufficient distance such that the shaft may be withdrawn from the locking housing. The ability to lock and unlock the connector assembly requires no additional tools or parts apart from a magnetic key.
Nance, Thomas A. (Aiken, SC)
Magnetocapacitance without magnetoelectric coupling
The existence of a magnetodielectric (magnetocapacitance) effect is often used as a test for multiferroic behavior in new material systems. However, strong magnetodielectric effects can also be achieved through a combination of magnetoresistance and the Maxwell-Wagner effect, unrelated to true magnetoelectric coupling. The fact that this resistive magnetocapacitance does not require multiferroic materials may be advantageous for practical applications. Conversely, however, it also implies that magnetocapacitance per se is not sufficient to establish that a material is multiferroic.
Catalan, G.
Pathogenic agents in freshwater resources
Numerous pathogenic agents have been found in freshwaters used as sources for water supplies, recreational bathing and irrigation. These agents include bacterial pathogens, enteric viruses, several protozoans and parasitic worms more common to tropical waters. Although infected humans are a major source of pathogens, farm animals (cattle, sheep, pigs), animal pets (dogs, cats) and wildlife serve as significant reservoirs and should not be ignored. The range of infected individuals within a given warm-blooded animal group (humans included) may range from 1 to 25%. Survival times for pathogens in the water environment may range from a few days to as much as a year (Ascaris, Taenia eggs), with infective dose levels varying from one viable cell for several primary pathogenic agents to many thousands of cells for a given opportunistic pathogen.As pathogen detection in water is complex and not readily incorporated into routine monitoring, a surrogate is necessary. In general, indicators of faecal contamination provide a positive correlation with intestinal pathogen occurrences only when appropriate sample volumes are examined by sensitive methodology.Pathways by which pathogens reach susceptible water users include ingestion of contaminated water, body contact with polluted recreational waters and consumption of salad crops irrigated by polluted freshwaters. Major contributors to the spread of various water-borne pathogens are sewage, polluted surface waters and stormwater runoff. All of these contributions are intensified during periods of major floods. Several water-borne case histories are cited as examples of breakdowns in public health protection related to water supply, recreational waters and the consumption of contaminated salad crops. In the long term, water resource management must focus on pollution prevention from point sources of waste discharges and the spread of pathogens in watershed stormwater runoff.
Geldreich, Edwin E.
Synchronization of mutually coupled systems
General operation conditions to obtain anticipated or retarded synchronization in a mutually coupled system with feedback are analyzed. Different from a unidirectionally coupled system, which type of synchronization will occur in a mutually coupled system does not solely depend on the difference between the feedback-delay time and the coupling-delay time. We find that in addition to the feedback/coupling delay times, feedback strengths and coupling strengths all determine whether the system will preform anticipated or retarded synchronization. Experimental implementation using semiconductor lasers subject to optoelectronic feedback is provided as an example. A set of experimental data is presented and discussed.
Chiang, Margaret C.; Chen, How-Foo; Liu, Jia-Ming
Stochastic Coupled Cluster Theory
In an extension of the Full Configuration Interaction Monte Carlo method of Alavi et al.[1], I describe a stochastic algorithm to perform Coupled Cluster Theory[2] which represents excitation amplitudes as populations discrete excitation particles (excips) in the space of excitation operators (excitors). Re-expressing the Coupled Cluster equations as the dynamics of excips in this space, we show that a simple set of rules consisting of spawning, death, and annihilation steps suffice to evolve a distribution of in the space of excitors to sample the Coupled Cluster solution and correctly evaluate its energy. These rules are extremely simple to implement and not truncation-specific and thus this method can calculate solutions to an arbitrary level of truncation. I present results of CCSDTQ calculations on the neon atom with basis sets up to cc-pV6Z as well as calculations on the uniform electron gas beyond the capability of other present methods. [1pt] [1] GH Booth, AJW Thom, A Alavi, J. Chem. Phys. (2009) 131, 054106 [1pt] [2] AJW Thom, Phys. Rev. Lett. (2010) 105, 263004
Thom, Alex J. W.
Quality control of decontaminating agents.
The present study evaluates the efficiency of the following decontaminating agents for the multiresistant, locally circulating bacterium Pseudomonas aeruginosa: glutaraldehyde 2%--makes A and B-, glutaraldehyde-formaldehyde; povidone-iodine-makes A, B and C-; sodium hypochloride; chloroxylenol--makes A and B-; and lapire chloride. The 9027 ATCC strain was used as a standard. A modification of the method of Kelsey and Sykes (1) was used to evaluate decontaminating efficiency. Highly satisfactory results were obtained with glutaraldehide 2% A and B, glutaraldehyde-formaldehyde and sodium hypochlorite. The results for povidone-iodine A, B and C were satisfactory but were unsatisfactory for chloroxylenol and lapirium chloride. PMID:12905908
Arancegui, N; Cabanillas, M; Martinez, A; Funosas, E; Maestri, L; Hermida Lucena, P
Method For Detecting Biological Agents
A sensor is provided including a polymer capable of having an alterable measurable property from the group of luminescence and electrical conductivity, the polymer having an intermediate combination of a recognition element, a tethering element and a property-altering element bound thereto and capable of altering the measurable property, the intermediate combination adapted for subsequent separation from the polymer upon exposure to an agent having an affinity for binding to the recognition element whereupon the separation of the intermediate combination from the polymer results in a detectable change in the alterable measurable property, and, detecting said detectable change in the alterable measurable property.
Chen, Liaohai (Los Alamos, NM); McBranch, Duncan W. (Santa Fe, NM); Wang, Hsing-Lin (Los Alamos, NM); Whitten, David G. (Santa Fe, NM)
Pleconaril, a novel antipicornaviral agent.
Despite the availability of therapy for selected symptoms, no specific antiviral agents are available to treat or prevent infections due to the viruses of the Picornaviridae family--rhinoviruses and enteroviruses. Characterization of the three-dimensional structure of picornaviruses in the 1980s allowed development of compounds targeted at the virus itself. Pleconaril is a novel, orally available, systemically acting molecule whose pharmacokinetics are characterized by a two-compartment open model with first-order absorption and with a safety profile similar to that of placebo. It shows promising results in treatment of picornaviral respiratory tract infections, meningitis, and other life-threatening infections. PMID:12627933
Florea, Naomi R; Maglio, Dana; Nicolau, David P
Elemental imaging of MRI contrast agents: benchmarking of LA-ICP-MS to MRI.
Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has been used to map the spatial distribution of magnetic resonance imaging (MRI) contrast agents (Gd-based) in histological sections in order to explore synergies with in vivo MRI. Images from respective techniques are presented for two separate studies namely (1) convection enhanced delivery of a Gd nanocomplex (developmental therapeutic) into rat brain and (2) convection enhanced delivery, with co-infusion of Magnevist (commercial Gd contrast agent) and Carboplatin (chemotherapy drug), into pig brain. The LA technique was shown to be a powerful compliment to MRI not only in offering improved sensitivity, spatial resolution and signal quantitation but also in giving added value regarding the fate of administered agents (Gd and Pt agents). Furthermore simultaneous measurement of Fe enabled assignment of an anomalous contrast enhancement region in rat brain to haemorrhage at the infusion site. PMID:22526651
Pugh, J A T; Cox, A G; McLeod, C W; Bunch, J; Writer, M J; Hart, S L; Bienemann, A; White, E; Bell, J
Anchor Toolkit - a secure mobile agent system
Mobile agent technology facilitates intelligent operation insoftware systems with less human interaction. Major challenge todeployment of mobile agents include secure transmission of agents andpreventing unauthorized access to resources between interacting systems,as either hosts, or agents, or both can act maliciously. The Anchortoolkit, designed by LBNL, handles the transmission and secure managementof mobile agents in a heterogeneous distributed computing environment. Itprovides users with the option of incorporating their security managers.This paper concentrates on the architecture, features, access control anddeployment of Anchor toolkit. Application of this toolkit in a securedistributed CVS environment is discussed as a case study.
Mudumbai, Srilekha S.; Johnston, William; Essiari, Abdelilah
Modeling Agents for Providing User Interface Assistance: The Design of the GAIA Interaction Agent
This paper presents the architectural design of the GAIA interaction agent. Interaction agents implement the metaphor of the agent\\/personal assistant for computer-based environments that are innovative and rich in functionality thus have a tendency to produce information overload and are possibly difficult to use. Brokerage systems are typically such complex environments. The manner by which interaction agents can provide useful
Agent Communication Network - A Mobile Agent Computation Model for Internet Applications
We propose a graph-based model, with a simulation, for the mobile agents to evolve over the Internet. Based on the concepts of Food Web (or Food Chain), one of the natural laws that we may use besides neural networks and genetic algorithms, we define an agent niche overlap graph and agent evolution states for the distributed computation of mobile agent
Timothy K. Shih
Evaluation of new antiemetic agents and definition of antineoplastic agent emetogenicity�an update
Development of effective antiemetic therapy depends upon an understanding of both the antiemetic agents and the emetogenic challenges these agents are designed to address. New potential antiemetic agents should be studied in an orderly manner, proceeding from phase I to phase II open-label trials and then to randomized double-blind phase III trials comparing new agents and regimens to best standard
Steven M. Grunberg; David Osoba; Paul J. Hesketh; Richard J. Gralla; Sussanne Borjeson; Bernardo L. Rapoport; Andreas du Bois; Maurizio Tonato
Subcutaneous administration of anticancer agents.
In recent years, much has been discussed on the development of oral anticancer treatment in terms of practical aspects and convenience for the patient. Less has been devoted to the potential of subcutaneous administration as a parenteral alternative. However, recent approvals (bortezomib, omacetaxine, trastuzumab) seem to show a renewed interest in this route of administration. All anticancer agents given subcutaneously display a very high bioavailability (>80%) and are rapidly absorbed (except the monoclonal antibodies trastuzumab and alemtuzumab). Subcutaneous delivery does not impact on the rate of elimination when compared to the intravenous route (azacitidine, cladribine, bortezomib, trastuzumab). Some formulations may be self-administered in educated patients (methotrexate, cladribine) but others require hospitalization (omacetaxine). When available, comparative studies with intravenous administration showed comparable clinical issues with an advantage for subcutaneous bortezomib with regard to the occurrence of peripheral neurotoxicity. Subcutaneous formulations of trastuzumab and, in the future rituximab, may allow for ambulatory treatment and self-administration. From an economic point of view, subcutaneous formulations of monoclonal antibodies may lead to lower healthcare costs but will have to face the arrival of less expensive intravenous biologically similar agents ('biosimilars') that will reduce the cost of hospitalization. PMID:24692685
Leveque, Dominique
Arsenic compounds as anticancer agents.
In this paper the use of arsenic compounds as anticancer agents in clinical trials and in in vitro investigations is reviewed, including the experience at our institute. Treatment of newly diagnosed and relapsed patients with acute promyelocytic leukemia (APL) with arsenic trioxide (As2O3) has been found to result in complete remission (CR) rates of 85-93% when given by intravenous infusion for 2-3 h at a dose of 10 mg/day diluted in 5% glucose saline solution. Patients exhibit a response in 28-42 days. CR rates after administration of Composite Indigo Naturalis tablets containing arsenic sulfide and of pure tetraarsenic tetrasulfide reached 98% and 84.9%, respectively. At higher concentrations (1-2 microM), arsenic induced apoptosis, while at lower concentrations (0.1-0.5 microM), it triggered cell differentiation in vitro. As2O3-induced apoptosis has been observed in many cancer cell lines, including esophageal carcinoma, gastric cancer, neuroblastoma, lymphoid malignancies, and multiple myeloma. Its effectiveness was confirmed in the treatment of multiple myeloma. Arsenic compounds are effective agents in the treatment of APL and their activity against other types of cancer requires further investigation. PMID:11587371
Wang, Z Y