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An interview with Hyeon-Shik Hwang
Thiesen, Guilherme; de Araújo, Telma Martins; Freitas, Maria Perpétua Mota; da Motta, Alexandre Trindade Simões
It gives me great pleasure to interview Dr. Hyeon-Shik Hwang, an innovative orthodontist who has developed many creative techniques over his career. Dr. Hwang was born in Korea and received his DDS and PhD degrees from Yonsei University in Seoul. He is professor and chairman of the Department of Orthodontics at Chonnam National University School of Dentistry, Gwangju, Korea. Dr. Hwang, as a faculty at the university hospital, has maintained a successful clinical practice for more than 25 years. He has treated many adult patients focusing on esthetics and periodontal health and has developed many clinical techniques to improve the effectiveness and efficiency of treatment to the benefit of both the patient and practitioner. Dr. Hwang is also interested in the evaluation of facial asymmetry two- and three-dimensionally. As one of the early adopters of cone-beam volume imaging, he has given special emphasis on the management of surgical cases. He is married to Jung-Un Park with whom he has two sons. His favorite hobbies are photography and listening to music. When I was presented to him in a congress, it was a great pleasure meeting someone who I already admired for his singular work. Later on, his humbleness and knowledge made me marvel at him even more. I hope that all readers of Dental Press Journal of Orthodontics also enjoy the teachings from this brilliant Korean orthodontist! Guilherme Thiesen - interview coordinator PMID:27007758
The legacy of the Hwang case: research misconduct in biosciences.
Kakuk, Péter
This paper focuses on the infamous case of Hwang Woo Suk, the South-Korean national hero and once celebrated pioneer of stem cell research. After briefly discussing the evolution of his publication and research scandal in Science, I will attempt to outline the main reactions that emerged within scientific and bioethical discourses on the problem of research misconduct in contemporary biosciences. What were the ethical lapses in his research? What kind of research misconduct has been identified? How this kind of misconduct affects scientific integrity? How to avoid it? Focusing on these questions, the paper interprets the Hwang's case as a case study that might shed light on the worst aspects of highstakes global science. This case presents a group of problems that might endanger scientific integrity and public trust. Regulatory oversight, ethical requirements and institutional safeguards are often viewed by the scientific community as merely decelerating scientific progress and causing delays in the application of treatments. The Hwang's case represents how unimpeded progress works in contemporary science. Thus, the case might shed light on the often neglected benefits of "the social control of science".
Synechocystis sp. PCC 6803 CruA (sll0147) encodes lycopene cyclase and requires bound chlorophyll a for activity.
Xiong, Wei; Shen, Gaozhong; Bryant, Donald A
The genome of the model cyanobacterium, Synechococcus sp. PCC 7002, encodes two paralogs of CruA-type lycopene cyclases, SynPCC7002_A2153 and SynPCC7002_A0043, which are denoted cruA and cruP, respectively. Unlike the wild-type strain, a cruA deletion mutant is light-sensitive, grows slowly, and accumulates lycopene, γ-carotene, and 1-OH-lycopene; however, this strain still produces β-carotene and other carotenoids derived from it. Expression of cruA from Synechocystis sp. PCC 6803 (cruA 6803) in Escherichia coli strains that synthesize either lycopene or γ-carotene did not lead to the synthesis of either γ-carotene or β-carotene, respectively. However, expression of this orthologous cruA 6803 gene (sll0147) in the Synechococcus sp. PCC 7002 cruA deletion mutant produced strains with phenotypic properties identical to the wild type. CruA6803 was purified from Synechococcus sp. PCC 7002 by affinity chromatography, and the purified protein was pale yellow-green due to the presence of bound chlorophyll (Chl) a and β-carotene. Native polyacrylamide gel electrophoresis of the partly purified protein in the presence of lithium dodecylsulfate at 4 °C confirmed that the protein was yellow-green in color. When purified CruA6803 was assayed in vitro with either lycopene or γ-carotene as substrate, β-carotene was synthesized. These data establish that CruA6803 is a lycopene cyclase and that it requires a bound Chl a molecule for activity. Possible binding sites for Chl a and the potential regulatory role of the Chl a in coordination of Chl and carotenoid biosynthesis are discussed.
Justification and Persuasion about Cloning: Arguments in Hwang's Paper and Journalistic Reported Versions
ERIC Educational Resources Information Center
Jimenez-Aleixandre, Maria Pilar; Federico-Agraso, Marta
We examine the argumentative structure of Hwang et al.'s (2004) paper about human somatic cell nuclear transfer (SCNT, or "therapeutic cloning"), contrasted with four Journalistic Reported Versions (JRV) of it, and with students' summaries of one JRV. As the evaluation of evidence is one of the critical features of argumentation…
Justification and Persuasion about Cloning: Arguments in Hwang's Paper and Journalistic Reported Versions
NASA Astrophysics Data System (ADS)
Jiménez-Aleixandre, María Pilar; Federico-Agraso, Marta
We examine the argumentative structure of Hwang et al.'s (2004) paper about human somatic cell nuclear transfer (SCNT, or 'therapeutic cloning'), contrasted with four Journalistic Reported Versions (JRV) of it, and with students' summaries of one JRV. As the evaluation of evidence is one of the critical features of argumentation (Jiménez-Aleixandre 2008), the analysis focuses on the use of evidence, drawing from instruments to analyze written argumentation (Kelly et al. 2008) and from studies about the structure of empirical research reports (Swales 2001). The objectives are: 1) To examine the use of evidence and the argumentative structure of Hwang et al.'s Science, 303: 1669-1674 (2004) original paper in terms of the criteria: a) pertinence of the evidence presented to the claims; b) sufficiency of the evidence for the purpose of supporting the claims; and c) coordination of the evidence across epistemic levels. 2) To explore how the structure of Hwang's paper translates into the JRV and into university students' perceptions about the evidence supporting the claims. The argumentative structure of Hwang's paper is such that its apparently ostensible main claim about NT constitutes a justification for a second claim about its therapeutic applications, for which no evidence is offered. However, this second claim receives prominent treatment in the JRV and in the students' summaries. Implications for promoting critical reading in the classroom are discussed.
Reclassification of Halomonas caseinilytica Wu et al. 2008 as a later synonym of Halomonas sinaiensis-Comments on the proposal by Hwang et al., Antonie van Leeuwenhoek 109:1345-1352, 2016.
Oren, Aharon
Hwang et al. (Antonie van Leeuwenhoek 109:1345-1352, 2016) proposed the reclassification of Halomonas caseinilytica (Wu et al. 2008) as a later synonym of Halomonas sinaiensis, based on the publication of the latter name in 2007 by Romano et al. However, the name H. sinaiensis was validly published only in 2011. Therefore the proposal by Hwang et al. is not appropriate; instead, the name H. sinaiensis can be proposed as a later synonym of H. casinilytica.
Spatial Distribution of a Large Herbivore Community at Waterholes: An Assessment of Its Stability over Years in Hwange National Park, Zimbabwe
Chamaillé-Jammes, Simon; Charbonnel, Anaïs; Dray, Stéphane; Madzikanda, Hillary; Fritz, Hervé
The spatial structuring of populations or communities is an important driver of their functioning and their influence on ecosystems. Identifying the (in)stability of the spatial structure of populations is a first step towards understanding the underlying causes of these structures. Here we studied the relative importance of spatial vs. interannual variability in explaining the patterns of abundance of a large herbivore community (8 species) at waterholes in Hwange National Park (Zimbabwe). We analyzed census data collected over 13 years using multivariate methods. Our results showed that variability in the census data was mostly explained by the spatial structure of the community, as some waterholes had consistently greater herbivore abundance than others. Some temporal variability probably linked to Park-scale migration dependent on annual rainfall was noticeable, however. Once this was accounted for, little temporal variability remained to be explained, suggesting that other factors affecting herbivore abundance over time had a negligible effect at the scale of the study. The extent of spatial and temporal variability in census data was also measured for each species. This study could help in projecting the consequences of surface water management, and more generally presents a methodological framework to simultaneously address the relative importance of spatial vs. temporal effects in driving the distribution of organisms across landscapes. PMID:27074044
Spatial Distribution of a Large Herbivore Community at Waterholes: An Assessment of Its Stability over Years in Hwange National Park, Zimbabwe.
Chamaillé-Jammes, Simon; Charbonnel, Anaïs; Dray, Stéphane; Madzikanda, Hillary; Fritz, Hervé
The spatial structuring of populations or communities is an important driver of their functioning and their influence on ecosystems. Identifying the (in)stability of the spatial structure of populations is a first step towards understanding the underlying causes of these structures. Here we studied the relative importance of spatial vs. interannual variability in explaining the patterns of abundance of a large herbivore community (8 species) at waterholes in Hwange National Park (Zimbabwe). We analyzed census data collected over 13 years using multivariate methods. Our results showed that variability in the census data was mostly explained by the spatial structure of the community, as some waterholes had consistently greater herbivore abundance than others. Some temporal variability probably linked to Park-scale migration dependent on annual rainfall was noticeable, however. Once this was accounted for, little temporal variability remained to be explained, suggesting that other factors affecting herbivore abundance over time had a negligible effect at the scale of the study. The extent of spatial and temporal variability in census data was also measured for each species. This study could help in projecting the consequences of surface water management, and more generally presents a methodological framework to simultaneously address the relative importance of spatial vs. temporal effects in driving the distribution of organisms across landscapes.
Oversight framework over oocyte procurement for somatic cell nuclear transfer: comparative analysis of the Hwang Woo Suk case under South Korean bioethics law and U.S. guidelines for human embryonic stem cell research.
Kim, Mi-Kyung
We examine whether the current regulatory regime instituted in South Korea and the United States would have prevented Hwang's potential transgressions in oocyte procurement for somatic cell nuclear transfer, we compare the general aspects and oversight framework of the Bioethics and Biosafety Act in South Korea and the US National Academies' Guidelines for Human Embryonic Stem Cell Research, and apply the relevant provisions and recommendations to each transgression. We conclude that the Act would institute centralized oversight under governmental auspices while the Guidelines recommend politically-independent, decentralized oversight bodies including a special review body for human embryonic stem cell research at an institutional level and that the Guidelines would have provided more vigorous protection for the women who had undergone oocyte procurement for Hwang's research than the Act. We also suggest additional regulations to protect those who provide oocytes for research in South Korea.
An Ecological Paradox: The African Wild Dog (Lycaon Pictus) Is Not Attracted to Water Points When Water Is Scarce in Hwange National Park, Zimbabwe
Ndaimani, Henry; Tagwireyi, Paradzayi; Sebele, Lovelater; Madzikanda, Hillary
In dry biomes, spatio-temporal variation in surface water resource stocks is pervasive, with unknown effects on the ranging behaviour of large predators. This study assessed the effect of spatial variation in surface water resources on the ranging behaviour of the African wild dog (Lycaon pictus). We analyzed data for 1992 (dry year with 20 water points) and 2000 (wet year with 30 water points) against presence-only data for five packs of L. pictus in a part of Hwange National Park and adjacent smallholder communal farming areas in western Zimbabwe. Modelling the potential habitat for L. pictus using Maxent with distance from water points (Dw) and Normalized Difference Vegetation Index (NDVI) as predictor variables was successful for 2000 (AUC = 0.793) but not successful for 1992 (AUC = 0.423), with L. pictus probability of occurrence near water points being more for year 2000 than for year 1992. The predicted L. pictus range was wider in 1992 (~13888.1 km2) than in 2000 (~958.4 km2) (Test of Proportions, χ2 = 124.52, df = 1, P = 0.00). Using the 2nd order Multitype Nearest Neighbour Distance Function (Gcross), we also observed significant attraction between L. pictus and water points within only ~1km radius for 1992 but up to ~8km radius for 2000. Our study reinforced the notion that surface water resources attract wild dogs in the savannahs but paradoxically less so when water resources are scarce. In particular, our study furthers current understanding of the effects of changing water availability regimes on the endangered L. pictus, providing evidence that the endangered predator's home range encroaches into potential ecological traps (i.e., smallholder communal farming areas) when water resources are scarce. PMID:26816321
An Ecological Paradox: The African Wild Dog (Lycaon Pictus) Is Not Attracted to Water Points When Water Is Scarce in Hwange National Park, Zimbabwe.
Ndaimani, Henry; Tagwireyi, Paradzayi; Sebele, Lovelater; Madzikanda, Hillary
In dry biomes, spatio-temporal variation in surface water resource stocks is pervasive, with unknown effects on the ranging behaviour of large predators. This study assessed the effect of spatial variation in surface water resources on the ranging behaviour of the African wild dog (Lycaon pictus). We analyzed data for 1992 (dry year with 20 water points) and 2000 (wet year with 30 water points) against presence-only data for five packs of L. pictus in a part of Hwange National Park and adjacent smallholder communal farming areas in western Zimbabwe. Modelling the potential habitat for L. pictus using Maxent with distance from water points (Dw) and Normalized Difference Vegetation Index (NDVI) as predictor variables was successful for 2000 (AUC = 0.793) but not successful for 1992 (AUC = 0.423), with L. pictus probability of occurrence near water points being more for year 2000 than for year 1992. The predicted L. pictus range was wider in 1992 (~13888.1 km2) than in 2000 (~958.4 km2) (Test of Proportions, χ2 = 124.52, df = 1, P = 0.00). Using the 2nd order Multitype Nearest Neighbour Distance Function (Gcross), we also observed significant attraction between L. pictus and water points within only ~1km radius for 1992 but up to ~8km radius for 2000. Our study reinforced the notion that surface water resources attract wild dogs in the savannahs but paradoxically less so when water resources are scarce. In particular, our study furthers current understanding of the effects of changing water availability regimes on the endangered L. pictus, providing evidence that the endangered predator's home range encroaches into potential ecological traps (i.e., smallholder communal farming areas) when water resources are scarce.
Insights for integrated conservation from attitudes of people toward protected areas near Hwange National Park, Zimbabwe.
Guerbois, Chloe; Dufour, Anne-Beatrice; Mtare, Godfrey; Fritz, Herve
Increase in human settlements at the edge of protected areas (PAs) is perceived as a major threat to conservation of biodiversity. Although it is crucial to integrate the interests of surrounding communities into PA management, key drivers of changes in local populations and the effects of conservation on local livelihoods and perceptions remain poorly understood. We assessed population changes from 1990 to 2010 in 9 villages located between 2 PAs with different management policies (access to natural resources or not). We conducted semi-directive interviews at the household level (n =217) to document reasons for settlement in the area and villager's attitudes toward the PAs. We examined drivers of these attitudes relative to household typology, feelings about conservation, and concerns for the future with mixed linear models. Population increased by 61% from 2000 to 2010, a period of political and economic crisis in Zimbabwe. Forty-seven percent of immigrants were attracted by the area; others had been resettled from other villages or were returning to family lands. Attitudes toward PAs were generally positive, but immigrants attracted by the area and who used resources within the PA with fewer restrictions expressed more negative attitudes toward PAs. Household location, losses due to wild animals, and restrictions on access to natural resources were the main drivers of this negative attitude. Profit-seeking migrants did not expect these constraints and were particularly concerned with local overpopulation and access to natural resources. To avoid socio-ecological traps near PAs (i.e., unforeseen reduced adaptive capacity) integrated conservation should address mismatches between management policy and local expectations. This requires accounting for endogenous processes, for example, local socio-ecological dynamics and values that shape the coexistence between humans and wildlife.
The Effect of Defense R&D Expenditures on Military Capability and Technological Spillover
offshore oil and the high level of social infrastructure, which skews its per capita measurements. Hwang (2008) proposed another measure of national...RANK Morocco 0.10989 0.139331781 36 Indonesia 0.102897 0.130465213 37 North Korea 0.10274 0.130266149 38 Belgium 0.10258 0.130063282 39... Morocco 0.0044709 37 16710894414 71 55 COUNTRY CINC* CINC RANK HWANG ** HWANG RANK Syrian Arab Republic 0.0044535 38 52945275034 53
Membrane-Mediated Extraction and Biodegradation of Volatile Organic Compounds From Air
mixtures through PTMSP." Makromol. Chem. Rapid Commun. 7: 43. Ji, W., S.K. Sikdar , and S.–T. Hwang (1994a). "Modeling of multicomponent...pervaporation for removal of volatile organic compounds from water." J. Membrane Sci. 93: 1. Ji, W., A. Hilaly, S.K. Sikdar , and S.–T. Hwang (1994b
Isorenieratene Biosynthesis in Green Sulfur Bacteria Requires the Cooperative Actions of Two Carotenoid Cyclases▿ †
Maresca, Julia A.; Romberger, Steven P.; Bryant, Donald A.
The cyclization of lycopene to γ- or β-carotene is a major branch point in the biosynthesis of carotenoids in photosynthetic bacteria. Four families of carotenoid cyclases are known, and each family includes both mono- and dicyclases, which catalyze the formation of γ- and β-carotene, respectively. Green sulfur bacteria (GSB) synthesize aromatic carotenoids, of which the most commonly occurring types are the monocyclic chlorobactene and the dicyclic isorenieratene. Recently, the cruA gene, encoding a conserved hypothetical protein found in the genomes of all GSB and some cyanobacteria, was identified as a lycopene cyclase. Further genomic analyses have found that all available fully sequenced genomes of GSB encode an ortholog of cruA. Additionally, the genomes of all isorenieratene-producing species of GSB encode a cruA paralog, now named cruB. The cruA gene from the chlorobactene-producing GSB species Chlorobaculum tepidum and both cruA and cruB from the brown-colored, isorenieratene-producing GSB species Chlorobium phaeobacteroides strain DSM 266T were heterologously expressed in lycopene- and neurosporene-producing strains of Escherichia coli, and the cruB gene of Chlorobium clathratiforme strain DSM 5477T was also heterologously expressed in C. tepidum by inserting the gene at the bchU locus. The results show that CruA is probably a lycopene monocyclase in all GSB and that CruB is a γ-carotene cyclase in isorenieratene-producing species. Consequently, the branch point for the synthesis of mono- and dicyclic carotenoids in GSB seems to be the modification of γ-carotene, rather than the cyclization of lycopene as occurs in cyanobacteria. PMID:18676669
Symposium on Flow-Induced Vibrations Held in New Orleans, Louisiana on 9-14 December 1984. Volume 1. Excitation and Vibration of Bluff Bodies in Cross Flow
84 140 144 3 - 3 3 l J(1975-1978) -.. I BUGEY 128 61 108 140 68 68 68 6 3 21978-1981) CRUAS 155 78 136 160 76 76 76 8 3 3 (1.981) . .. .. Table I...that real loads can be reproduced (figure 5). Height increase.When height was increased from 128 m ( Bugey ) to 160 m (Cruas), no perceptible difference...Z) where K(O)- assumes the values 1.3, 1.5, 0.85 and 0.5 in the four zones, at the neck in Bugey , with : up and a standard deviation of pressure and
A Study of the Tolerance of ROK Air Force Personnel to Gz Centrifugation,
TO +Gz CENTRIFUGATION AaJ. Byung Kook Lee, M.D., Capt. Jung Min Hwang, M.D., Capt. Jong Sang Chois, M.D.7-C-pt. Sang Goo Shin , M.D., Joung K. Park...Centrifugation Aeromedical Research Center Maj., Byung Kook Lee, M.D. Capt., Jung Min Hwang, M.D. Capt., Jong Sang Chois, M.D. Capt., Sang Goo Shin , M.D...DIVISION A STUDY OF THE TOLERANCE OF ROK AIR FORCE PERSONNEL TO+Gz CENTRIFUGATION by Byung Kook Lee, Jung Min Hwang, et al. 0 L..I IA -J Approved for public
Using New Maps to Navigate Cancer Treatment - TCGA
Drs.Scott Hwang and Chad Holder of Emory University discuss the development of VARSARI and The Cancer Imaging Program's TCGA Radiology Initiative. Learn more about their and Dr. Carl Jaffe's work in this TCGA In Action Case Study.
Oviposition-Modifying Substances for Mosquitoes.
preference may be due to the presence of oviposition pheromones or oviposition attractants and repellents in natural habitats. These oviposition -modifying...LfD-R125 421 OVIPOSITION -MODIFYING SUBSTANCES FOR MOSQUITOES(U) 11 I CALIFORNIA UNIV RIVERSIDE DEPT OF ENTOMOLOGY Y HWANG I 91 JUL 81 DANDi?7-79-C...STANDARDS- 1963-A ." !', -b b', -1 I- I 1. AD__ _ _ _ * N 3 OVIPOSITION -MODIFYING SUBSTANCES FOR MOSQUITOES Final Report Yih-Shen Hwang * July 1, 1981
Prostate Cancer Aggressiveness Gene in Hereditary Prostate Cancer
with REA, and estrogen receptor corepressor. Breast Canc Res Treat., in press (2007). This grant provided research support for Dr Veda Giri while...an estrogen receptor corepressor Clara Hwang Æ Veda N. Giri Æ John C. Wilkinson Æ Casey W. Wright Æ Amanda S. Wilkinson Æ Kathleen A. Cooney Æ Colin S...histone deacetylases (HDAC), and members of the polycomb group (PcG) of proteins. Clara Hwang and Veda N. Giri contributed equally to this work. C
Altimeter Measurements of Wind and Wave Modulation by the Kuroshio in the Yellow and East China Seas
current theory of wave -current interaction (e.g., Hughes, 1978; profile U(y), the current shear Ujy), and the resulting Hwang and Shemdin , 1990). The...Evidence for ocean-to-atmosphere feedback. J. Climate, 16, Hwang, P. A. and 0. H. Shemdin (1990): Modulation of short 1404-1413. waves by surface...Journal of Oceanography, Vol. 61, pp. 987 to 993, 2005 Short Contribution Altimeter Measurements of Wind and Wave Modulation by the Kuroshio in the
Numerical Solutions for Bayes Sequential Decision Approach to Bioequivalence Problem
ADA3 707 2T1 -r Numerical Solutions for Bayes Sequential Decision Approach to Bioequivalence Problem Jing-Shiang Hwang Department of Statistics...Decision Approach to Bioequivalence Problem Jing-Shiang Hwang Department of Statistics Harvard University March 20, 1991 Abstract Bioequivalence is an...literatures. We address stop- ping rules for testing bioequivalence from a decision-theoretic point of view. The numerical techniques for Bayes
Supernova remnant rich fields in the Carina spiral arm
NASA Technical Reports Server (NTRS)
Markert, Thomas
The analysis of the ROSAT PSPC data on five fields containing supernova remnants several months ago was completed. Dr. Una Hwang, prepared a paper describing our results which was published last August ('An X-ray Study of Five Supernova Remnants in the Carina Spiral Arm', by Hwang and Markert, 1994, Ap. J., 431, p. 819). Hwang's earlier analysis of this data became part of her PhD thesis ( 'X-ray Studies of Supernova Remnants', February 1994, MIT). A copy of the Hwang and Markert paper is appended. The results of the study are well-summarized in the Hwang and Markert paper: the best spatial-spectral X-ray study yet made of the intriguing SNR G296.1-0.7 was obtained. This study showed interesting spectral variations over the surface of the object.It was also determined the gross physical properties of G296 based on its X-ray emission. Four other fields were also examined. For three of these the upper limits to the radio object were determined, and in one case found a weak, but statistically significant X-ray object coincident with the peak of the radio flux.
On the security of a simple three-party key exchange protocol without server's public keys.
Nam, Junghyun; Choo, Kim-Kwang Raymond; Park, Minkyu; Paik, Juryon; Won, Dongho
Authenticated key exchange protocols are of fundamental importance in securing communications and are now extensively deployed for use in various real-world network applications. In this work, we reveal major previously unpublished security vulnerabilities in the password-based authenticated three-party key exchange protocol according to Lee and Hwang (2010): (1) the Lee-Hwang protocol is susceptible to a man-in-the-middle attack and thus fails to achieve implicit key authentication; (2) the protocol cannot protect clients' passwords against an offline dictionary attack; and (3) the indistinguishability-based security of the protocol can be easily broken even in the presence of a passive adversary. We also propose an improved password-based authenticated three-party key exchange protocol that addresses the security vulnerabilities identified in the Lee-Hwang protocol.
Ultrasmall Microfabricated Laser Cavities
as 105-106 K/W, where material gain saturates and nonradiative processes overwhelm before the device can go into stimulated emission [17, 90, 96...K. Hwang, D.-S. Song, I.-Y. Han, and Y.-H. Lee, \\Effect of nonradiative recombination on light emitting properties of two dimensional photonic
An Integrated Decision Model for Evaluating Educational Web Sites from the Fuzzy Subjective and Objective Perspectives
ERIC Educational Resources Information Center
Huang, Tony Cheng-Kui; Huang, Chih-Hong
With advances in information and network technologies, lots of data have been digitized to reveal information for users by the construction of Web sites. Unfortunately, they are both overloading and overlapping in Internet so that users cannot distinguish their quality. To address this issue in education, Hwang, Huang, and Tseng proposed a group…
The Relative Effectiveness of Digital Game-Based Learning Types in English as a Foreign Language Setting: A Meta-Analysis
ERIC Educational Resources Information Center
Chiu, Yi-hui; Kao, Chian-wen; Reynolds, Barry Lee
During the past 10 years, the number of digital game-based learning (DGBL) studies has significantly increased (Hwang & Wu, 2012). DGBL is generally found to be positive over traditional instruction (Liao, 2010) and it has had great impact on education (Prensky, 2001). The DGBL effectiveness, however, might vary according to subjects taught or…
A View of the Tip of the Iceberg: Revisiting Conceptual Continuities and Their Implications for Science Learning
ERIC Educational Resources Information Center
Brown, Bryan A.; Kloser, Matt
We respond to Hwang and Kim and Yeo's critiques of the conceptual continuity framework in science education. First, we address the criticism that their analysis fails to recognize the situated perspective of learning by denying the dichotomy of the formal and informal knowledge as a starting point in the learning process. Second, we address the…
Beyond Authoritarian Personality: The Culture-Inclusive Theory of Chinese Authoritarian Orientation.
Chien, Chin-Lung
In a dyad interaction, respecting and obeying those with high status (authority) is highly valued in Chinese societies. Regarding explicit behaviors, Chinese people usually show respect to and obey authority, which we call authoritarian orientation. Previous literature has indicated that Chinese people have a high degree of authoritarian personality, which was considered a national character. However, under Confucian relationalism (Hwang, 2012a), authoritarian orientation is basically an ethical issue, and thus, should not be reduced to the contention of authoritarian personality. Based on Yang's (1993) indigenous conceptualization, Chien (2013) took an emic bottom-up approach to construct an indigenous model of Chinese authoritarian orientation; it represents a "culture-inclusive theory." However, Chien's model lacks the role of agency or intentionality. To resolve this issue and to achieve the epistemological goal of indigenous psychology (that is, "one mind, many mentalities"), this paper took the "cultural system approach" (Hwang, 2015b) to construct a culture-inclusive theory of authoritarian orientation in order to represent the universal mind of human beings as well as the mentalities of people in a particular culture. Two theories that reflect the universal mind, the "Face and Favor model" (Hwang, 1987) and the "Mandala Model of Self" (Hwang, 2011a,c), were used as analytical frameworks for interpreting Chien's original model. The process of constructing the culture-inclusive theory of authoritarian orientation may represent a paradigm for the construction of indigenous culture-inclusive theories while inspiring further development. Some future research directions are proposed herein.
An Alternative Approach to Combination Vaccines: Intradermal Administration of Isolated Components for Control of Anthrax, Botulism, Plague and Staphylococcal Toxic Shock
and identification of correlates of immunity. Clin Immunol 2003, 108:51-59. 18. Williamson ED, Eley SM , Stagg AJ, Green M, Russell P, Titball RW: A...2005, 159:1136-1144. 24. Mikszta JA, Sullivan VJ, Dean C, Waterston AM, Alarcon JB, Dekker JP 3rd, Brittingham JM, Huang J, Hwang CR, Ferriter M, Jiang
Harnessing Functional Genomics to Reverse Chemoresistance in Breast Cancer
tin g Cytokinesis Phagocytosis GLUT4 Exocyst RALB NF B IRF3 Others TBK1 Translational control As sem bly an d mo bil iza tio n En do cy to sis Innate...Inoue, M., Chang, L., Hwang, J., Chiang, S. H. & Saltiel, A. R. The exocyst complex is required for targeting of Glut4 to the plasma membrane by
78 FR 30921 - Ocean Transportation Intermediary License Applicants
Federal Register 2010, 2011, 2012, 2013, 2014
..., Application Type: New NVO & OFF License Dove Global Logistics, Inc. (NVO), 2160 Plaza Del Amo, Suite 161, Torrance, CA 90501, Officers: Chol Min Kim, President (QI), Eun Hwang, CFO, Application Type: New NVO.... dba Pacific Micronesian Lines (NVO), ] 1511 Glenn Curtiss Street, Carson, CA 90746, Officer:...
A Theory of the Origin of the State
ERIC Educational Resources Information Center
Carneiro, Robert L.
Suggests that states evolve in response to ecological or social circumscription, or resource concentration. When dense populations develop, fighting over land forces loser into political subordination or incorporation. This modification of coercive theories explain lack of state in Amazon basin and origin of Inca, Maya, Hwang Valley states.…
Single-molecule choreography between telomere proteins and G quadruplexes.
Hopfner, Karl-Peter
Telomeric DNA binds proteins to protect chromosome ends, but it also adopts G quadruplex (GQ) structures. Two new studies by Hwang and colleagues (in this issue of Structure) and Ray and colleagues (published elsewhere) use single molecule imaging to reveal how GQs affect the binding of different telomere associated proteins. The data suggest that GQs play important roles in regulating accessibility of telomeres.
Disruptive Basic Research Areas" – Metamaterials and Plasmonics – Quantum Information Science – Cognitive Neuroscience – Nanoscience and...Sayir, Fuller) Bio-Sensing of Magnetic Fields (Larkin, Bradshaw, Curcic, DeLong 2D Materials & Devices Beyond Graphene (Hwang, Pomrenke, Harrison
Proceedings of the Annual Meeting of the Association for Education in Journalism and Mass Communication (80th, Chicago, Illinois, July 30-August 2, 1997): Minorities and Communication.
ERIC Educational Resources Information Center
Association for Education in Journalism and Mass Communication.
The Minorities and Communication section of the Proceedings contains the following seven papers: "HIV/AIDS Video Programming for Latino Youth" (Hilary N. Karasz); "Use of Asian American History in the News Media: The Discourse of 'Model Minority'" (Chiung Hwang Chen and Ethan Yorgason); "No Racism Here: News Coverage of…
Students' Conceptions: Culturing Conceptions
ERIC Educational Resources Information Center
Tiberghien, Andree
This commentary on Roth, Lee, and Hwang's paper aims at analysing their theoretical approach in terms of its object of study, and the aspects that are brought to the fore, like the cultural activity of conversation, and those that are overshadowed, like the role of the material world and its perception on learning. This analysis, developed on the…
Assessing the Quality of the Common Core State Standards for Mathematics
ERIC Educational Resources Information Center
Cobb, Paul; Jackson, Kara
The authors comment on Porter, McMaken, Hwang, and Yang's recent analysis of the Common Core State Standards for Mathematics by critiquing their measures of the focus of the standards and the absence of an assessment of coherence. The authors then consider whether the standards are an improvement over most state mathematics standards by discussing…
Issues in Analyzing Alignment of Language Arts Common Core Standards with State Standards
ERIC Educational Resources Information Center
Beach, Richard W.
This commentary on Porter, McMaken, Hwang, and Yang's "Common Core Standards: The New U.S. Intended Curriculum," which finds a lack of alignment between the Common Core State Standards and state standards and assessments, suggests possible reasons for the lack of alignment. It also offers possible reasons for Porter et al.'s finding of a…
Correction: Dye adsorption mechanisms in TiO2 films, and their effects on the photodynamic and photovoltaic properties in dye-sensitized solar cells.
Hwang, Kyung-Jun; Shim, Wang-Geun; Kim, Dajung; An, Jongdeok; Im, Chan; Kim, Youngjin; Kim, Gunwoo; Choi, Chulmin; Kang, Sang Ook; Cho, Dae Won
Correction for 'Dye adsorption mechanisms in TiO2 films, and their effects on the photodynamic and photovoltaic properties in dye-sensitized solar cells' by Kyung-Jun Hwang et al., Phys. Chem. Chem. Phys., 2015, 17, 21974-21981.
ETD-02-047 (Martonen) GPRA # 10108
T. B. Martonen1, J. Schroeter2, Z. Zhang3, D. Hwang4, and J. S. Fleming5
1Experimental Toxicology Division, National Health and Environmental Effects Research Laboratory, Research Triangle Park...
EFL College Students' Attitudes towards Mobile Learning
ERIC Educational Resources Information Center
Dashti, Fatimah A.; Aldashti, Abdulmohsen A.
Recently, cell phones have received much attention in the context of EFL/ESL learning. Mobile learning, in general, and distant learning, in particular, in educational contexts has been approached by educationalist all over the world (Hwang & Chang, 2011). Presently, countries pay ample attention to mobile learning in education. Despite the…
S. Hwang, Thermal conductivity of thin films: measurement and microstructural effects, in Thin- film heat transfer, properties and processing, ed...thermal, electrical, optical and magnetic properties . As typical examples we mention microelectronics, optical coatings and multilayers for use in optical...interplay between mechanical properties (elastic moduli), thermal properties (thermal conductivity, thermal expansion coefficient), and optical
Growth of Thin Hetero-Epitaxial Layers of Graphite and Diamond on SIC for Carbon Based Electronics
Lett, Vol. 100, p. 0116602. 6. Measurement of Scattering Rate and Minimum Conductivity in Graphene. Y. W. Tan, Y. Zhang, K. Bolotin, Y. Zhao, S. Adam ... E . H. Hwang, S. Das Sarma, H. L. Stormer,. 2007, Phys. Rev., Vol. 99, p. 246803. 7. LEED AND Auger Electron Observations. A.J. Van Bommel, J.E
Quasiparticle properties in graphene
NASA Astrophysics Data System (ADS)
Hwang, Euyheon
The quasiparticle properties in both single layer and bilayer graphene are presented. We study the electron self-energy as well as the quasiparticle spectral function in graphene, taking into account electron-electron interaction in the leading order dynamically screened Coulomb coupling and electron-impurity interaction associated with quenched disorder. Our calculation of the self-energy provides the basis for calculating all one-electron properties of graphene. We provide analytical and numerical results for quasiparticle renormalization in graphene. Comparison with existing angle-resolved photoemission spectroscopy measurements shows broad qualitative and semiquantitative agreement between theory and experiment, for both the momentum-distribution and energy-distribution curves in the measured spectra. We also present the inelastic quasiparticle scattering rate and the carrier mean free path for energetic hot electrons as a function of carrier energy, density, and temperature, including both electron-electron and electron-phonon interactions. Our results are directly applicable to device structures where ballistic transport is relevant with inelastic scattering dominating over elastic scattering.[4pt] S. Das Sarma, S. Adam, E. H. Hwang, and E. Rossi, Rev. Mod. Phys. 83, 407 (2011). [0pt] E. H. Hwang, Ben Yu-Kuang Hu, and S. Das Sarma Phys. Rev. B 76, 115434 (2007). [0pt] E. H. Hwang and S. Das Sarma Phys. Rev. B 77, 081412 (2008). [0pt] Rajdeep Sensarma, E. H. Hwang, and S. Das Sarma, Phys. Rev. B 84, 041408(R) (2011).
Isotopic Constraints on the Sources and Associations of Organic Compounds in Marine Sediments
Caroline Grace, Amy Henneveld and Ethan Swan . The love and support of my family made all of this possible. 5 6 TABLE OF CONTENTS ABSTRACT 3 TABLE OF...slightly muted bomb signal in the long-chain FA it would not dilute it to the value observed. The study by Hwang and Morris, however was performed on
Regulation of Calcium Fluxes and Apoptosis by BCL-2 Family Proteins in Prostate Cancer Cells
sheep antimouse or donkey anti-rabbit antibody (Amersham Biosciences, Piscataway, NJ), 1:1000 dilution] for 2h at 4°C. Blots were washed 3X 10 min in...Clark, K., Stein, R., Dick , L., Hwang, D., and Goldberg, A. L. Inhibitors of the proteasome block the degradation of most cell proteins and the
Evaluation of U.S. Navy Tropical Cyclone Storm Surge Requirements in the Western North Pacific and Indian Oceans.
NAVENVPREDRSCHFAC Technical Report TR 77-03, 284 pp. c. Choi , B.H., 1980: Tidal Analysis of Inchon for the Years 1962-1972/1975-1977, KORDI Report 80-01. d. Hwang, C...Seoul, Korea, Hydro- graphic records and storm surge data. g. Chu, K.S., Personal storm surge data and calculations. h. Ahn, Myong- Bok , Personal storm
Pedagogical Implications on Medical Students' Linguistic Needs
ERIC Educational Resources Information Center
Hwang, Yanling
In this paper, an extended teaching implication is performed based on the study of medical students' linguistic needs in Tawian (Hwang, Lin, 2010). The aims of previous study were to provide a description of the linguistic needs and perceptions of medical students and faculty members in Taiwan. However, this paper put more thoughts on the…
Correction of the lack of commutability between plasmid DNA and genomic DNA for quantification of genetically modified organisms using pBSTopas as a model.
Zhang, Li; Wu, Yuhua; Wu, Gang; Cao, Yinglong; Lu, Changming
Plasmid calibrators are increasingly applied for polymerase chain reaction (PCR) analysis of genetically modified organisms (GMOs). To evaluate the commutability between plasmid DNA (pDNA) and genomic DNA (gDNA) as calibrators, a plasmid molecule, pBSTopas, was constructed, harboring a Topas 19/2 event-specific sequence and a partial sequence of the rapeseed reference gene CruA. Assays of the pDNA showed similar limits of detection (five copies for Topas 19/2 and CruA) and quantification (40 copies for Topas 19/2 and 20 for CruA) as those for the gDNA. Comparisons of plasmid and genomic standard curves indicated that the slopes, intercepts, and PCR efficiency for pBSTopas were significantly different from CRM Topas 19/2 gDNA for quantitative analysis of GMOs. Three correction methods were used to calibrate the quantitative analysis of control samples using pDNA as calibrators: model a, or coefficient value a (Cva); model b, or coefficient value b (Cvb); and the novel model c or coefficient formula (Cf). Cva and Cvb gave similar estimated values for the control samples, and the quantitative bias of the low concentration sample exceeded the acceptable range within ±25% in two of the four repeats. Using Cfs to normalize the Ct values of test samples, the estimated values were very close to the reference values (bias -13.27 to 13.05%). In the validation of control samples, model c was more appropriate than Cva or Cvb. The application of Cf allowed pBSTopas to substitute for Topas 19/2 gDNA as a calibrator to accurately quantify the GMO.
A Study on the Armillary Spheres of the Confucianists in Joseon Dynasty
NASA Astrophysics Data System (ADS)
Lee, Yong Sam; Kim, Sang Hyuk; Lee, Min Soo; Jeong, Jang Hae
Armillary sphere, generally known as, not only astronomical instrument for observing astronomical phenomena but also symbolizes the royal authority and royal political ideology which is based on Confucianism. Among the well-reputed Confucian scholars were built their own armillary spheres. However, these armillary spheres which exist are damaged and most of parts of its have been lost. We analyzed and measured the remnants of armillary spheres which were made by Toegye Lee Hwang, Uam Song Si-Yeol and Goedam Bae Sang-Yeol who were well-reputed Confucian scholars in Joseon Dynasty, and have been executed the restorations of Toegye Lee Hwang and Song Si-Yeols armillary sphere based on the drawings which were drawn as the original form by analysis and measurement of its remnants.
Authentication of Stephania tetrandra S. Moore (Fang Ji) and differentiation of its common adulterants using microscopy and HPLC analysis.
Joshi, Vaishali C; Avula, Bharathi; Khan, Ikhlas A
Stephania tetrandra S. Moore (Hang Fang Ji) is used in traditional Chinese medicine as a diuretic, an antiphlogistic, and an antirheumatic. The name "fang ji" is applied to at least four different genera of plants, including Aristolochia fangchi Y. C. Wu ex L. D. Chow and S. M. Hwang, Cocculus orbiculatus (L.) DC., Stephania tetrandra S. Moore, and Sinomenium acutum Rehder and E. H. Wilson. Due to similarity in the use of their common names, Stephania tetrandra S. Moore is often confused with Aristolochia fangchi Y. C. Wu ex L. D. Chow and S. M. Hwang, which has potentially dangerous consequences. To aid rapid and easy differentiation between the roots of these four species, so as to avoid possible contamination, detailed macroscopic and microscopic observations were made using stereo-and light-microscopy. The powdered samples were further analyzed using HPLC.
Physico-chemical and antioxidant properties of four mango (Mangifera indica L.) cultivars in China.
Liu, Feng-Xia; Fu, Shu-Fang; Bi, Xiu-Fang; Chen, Fang; Liao, Xiao-Jun; Hu, Xiao-Song; Wu, Ji-Hong
Four principal mango cultivars (Tainong No.1, Irwin, JinHwang and Keitt) grown in southern China were selected, and their physico-chemical and antioxidant properties were characterized and compared. Of all the four cultivars, Tainong No.1 had highest content of total phenols, ρ-coumaric acid, sinapic acid, quercetin, titratable acidity, citric acid, malic acid, fructose, higher antioxidant activities (DPPH, FRAP) and L(*), lower pH, PPO activity and individual weight. Keitt mangoes showed significantly (p<0.05) higher contents of β-carotene, ρ-hydroxybenzoic acid, sucrose, total sugar, total soluble solid, catechin, succinic acid and higher PPO activity. JinHwang mangoes exhibited significantly (p<0.05) higher individual weight and PPO activity, but had lower content of total phenols, β-carotene and lower antioxidant activity. Principal component analysis (PCA) allowed the four mango cultivars to be differentiated clearly based on all these physico-chemical and antioxidant properties determined in the study.
For love or money? The saga of Korean women who provided eggs for embryonic stem cell research.
Baylis, Françoise
In 2004 and 2005, Woo-Suk Hwang achieved international stardom with publications in Science reporting on successful research involving the creation of stem cells from cloned human embryos. The wonder and success all began to unravel, however, when serious ethical concerns were raised about the source of the eggs for this research. When the egg scandal had completely unfolded, it turned out that many of the women who provided eggs for stem cell research had not provided valid consents and that nearly 75% of the women egg providers had received cash or in-kind payments. Among those who did not receive direct benefits, some cited patriotism as their reason for participating in embryonic stem cell research, hence the question "for love or money?"--namely, patriotism versus payment. This paper summarizes the Hwang debacle with particular attention to the egg scandal and ends with some preliminary thoughts on patriotism as a motive for research participation.
Applications of Graphene to Photonics
graphene/ silicon carbide heterosystem," Physical Review B - Condensed Matter and Materials Physics 82 (2010). [63] S. Das Sarma and E. H. Hwang...the damage threshold of silicon for similar optical pulse parameters [19]. However, silicon has a 10-µm absorp- tion depth (at these wavelengths...example, using linear absorption a 1000x higher carrier density is created in graphene vs. silicon . Other notable optical properties include nonlinear
Program on Resorbable Radio Devices
The sputtering was performed at room temperature (RT) with an RF power of 250 W, immediately after cleaning the target with Ar plasma for 5 min. The...with simulation results. The operating fre- quencies extend up to ∼ 6 GHz. Simple inductors (Figure 1 f) S.-W. Hwang, Dr. X. Huang, S. Kim, Dr. S...as inductances, capaci- tances, and resistances, that yield a good match with the measured characteristics. The circuit simulations use these
Mathematical Simulation of the Cardiopulmonary System
in nature and include Dick and Rideout, (23) Noordergraaf, ( 4 - 7 ) Beneken, (10-12) Hwang, (14) and Croston .(15) 2. Those models addressing the...1971. 15. Croston , R. C., Rummel, J. A. and Kay, F. J. Computer model fo cardiovascular control system responses toexercise, Journal of Dynamic...the Lung. Marcel Dekker, Inc., N.Y., 1977. 37. Carnahan, B., Luther, H1. A. and Wilkes, J. 0. Applied Numerical Methods , John Wiley & Sons, Inc., 1969
Atomic Engineering of Superconductors by Design
fabricate novel heterostructures that exhibit high-temperature superconductivity . Design of heterostructures is accomplished using the predictive... superconductivity . Design of heterostructures is accomplished using the predictive capabilities of ab initio density functional theory (DFT) calculations... superconductivity , Physical Review B, (07 2011): 24526. doi: 10.1103/PhysRevB.84.024526 J. Kirtley, B. Kalisky, J. Bert, C. Bell, M. Kim, Y. Hikita, H. Hwang, J
Solar Cells: Homo-Tandem Polymer Solar Cells with VOC >1.8 V for Efficient PV-Driven Water Splitting (Adv. Mater. 17/2016).
Gao, Yangqin; Le Corre, Vincent M; Gaïtis, Alexandre; Neophytou, Marios; Hamid, Mahmoud Abdul; Takanabe, Kazuhiro; Beaujuge, Pierre M
On page 3366, P. M. Beaujuge and co-workers describe homo-tandem solar cells constructed by stacking identical subcells solution-processed from blends of the wide-bandgap polymer donor PBDTTPD and the fullerene acceptor PCBM, which achieve power conversion efficiencies >8% and open-circuit voltages >1.8 V. The homo-tandem devices provide sufficient voltage to induce the dissociation of water in an electrochemical cell. The authors acknowledge Hyun Ho Hwang (Heno) for developing the artwork.
Oviposition-Modifying Substances for Mosquitoes.
AD C: 2 OVIPOSITION -MODIFYING SUBSTANCES FOR MOSQUITOES Annual Summary Report YIH-SHEN HWANG * 'September 1, 1980 Supported by U.S. ARMY MEDICAL...NUMBER 2. GOVT ACCESSION NO. 3. RECIPIENT'S CATALOG NUMBER 4. TITLE (and Subtitle) S. TYPE OF REPORT & PERIOD COVERED OVIPOSITION -MODIFYING SUBSTANCES...nd identify by block number) MOSQUITOES/ OVIPOSITION -ATTRACTANTS/ OVIPOSITION -REPELLENTS/ OVIPOSITION - MODIFYING-SUBSTANCES/CARBOXYLIC-ACIDS/OCTANOIC
Selenium Potentiates Chemotherapeutic Selectivity: Improving Efficacy and Reducing Toxicity
regulates the rate-limiting step in global genomic repair through transcriptional control of the DNA damage recognition proteins xeroderma pigmentosum ...31). Xeroderma pigmentosum XPA cells defective in DNA repair served as a negative control for some experiments, as previously described (28). Cell...simian virus 40-transformed human cells. Mol Carcinog 2000;29:17–24. 14. Hwang BJ, Ford JM, Hanawalt PC, Chu G. Expression of the p48 xeroderma pigmentosum
Targeting Tim-1 to Circumvent Immune Tolerance in Prostate Cancer
Blumenstein, L. M. Glode, D. L. Bilhartz, M. Wyand, K. Manson , D. L. Panicali, R. Laus, J. Schlom, W. L. Dahut, P. M. Arlen, J. L. Gulley, and W. R...2122– 2132. [PubMed: 15169798] 12. Sanda MG, Smith DC, Charles LG, Hwang C, Pienta KJ, Schlom J, Milenic D, Panicali D, Montie JE. Recombinant...immunization. Prostate. 2009 15. Eng MH, Charles LG, Ross BD, Chrisp CE, Pienta KJ, Greenberg NM, Hsu CX, Sanda MG. Early castration reduces prostatic
Modeling and Simulation of Texture Evolution During the Thermomechanical Processing of Titanium Alloys (PREPRINT)
AFRL-RX-WP-TP-2008-4352 MODELING AND SIMULATION OF TEXTURE EVOLUTION DURING THE THERMOMECHANICAL PROCESSING OF TITANIUM ALLOYS (PREPRINT...the present article. 15. SUBJECT TERMS crystallographic texture, mechanical texturing, mechanical fibering, titanium alloy, thermomechanical...Thermomechanical Processing of Titanium Alloys S.L. Semiatin, S.V. Shevchenko*, O.M. Ivasishin*, M.G. Glavicic** Y.B. Chun***, and S.K. Hwang*** Air
Photophysical Properties on Functional Pi-Electronic Molecular Systems
2012, 48(45), 5611-5613 17. Low-Temperature Fabrication of TiO2 Electrodes for Flexible Dye-Sensitized Solar Cells Using an Electrospray Process...Sensitized Solar Cells Masatoshi Ishida , Sun Woo Park , Daesub Hwang , Young Bean Koo , Jonathan L. Sessler , Dong Young Kim , and Dongho Kim The...porphyrinoids such as expanded porphyrins, hybrid porphyrin tapes, etc. using theoretical calculations and various spectroscopic methodologies in conjunction
The Importance of Network Structure in High-K Dielectrics: LaAlO3, Pr2O3, and Ta2O5
CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a. NAME OF RESPONSIBLE PERSON Arthur Edwards a. REPORT Unclassified b. ABSTRACT...Space Vehicles Directorate, 3550 Aberdeen Avenue, Kirtland Air Force Base (AFB), New Mexico 87117 and Laboratoire d'Electrostatique et des Materiaux ...and A. Fissel, Solid -State Electron. 47, 2161 2003. 15S. Jeon, K. Im, H. Yang, H. Lee, H. Sim, S. Choi, T. Jang, and H. Hwang, Proceedings IEDM
Dependence of Radar Backscatter on the Energetics of the Air-Sea Interface
Shemdin , 1983; Keller and Gotwals, 1983) or a spatial array of sensors (Donelan, et al., 1985). It is much more common to have only a single wave ...Description of the (f. is the Frequency Corresponding Frequency Bounds of Region IV to Peak Energy in the Wave Height Spectrum) (from Shemdin and Hwang, 1988...parameters, here taken to be 50; the range of wave periods resolved is 0.6 to 8.0s. Following Der (1976), the sensors are capacitance transduction devices
SAXON I, (SAR X-Band and Ocean Nonlinearities). (1988/1990) Science Plan
1834. Hsiao, S.V. and O.H. Shemdin (1983) Measurement of Wind Velocity and Pressure with a Wave Follower , J. Geophys. Res., 88, 9841-9849. Hughes, B.A... Wave Follower , JPL Report No. 715-123, Pasadena, California. Shemdin , O.H. and P.A. Hwang (1988) Comparison of Measured and Predicted Sea Surface...October-December .... ............ 21 8. Wave Follower System in Operation with the Wave -Slope Sensor ..... ................ 26 9. Sketch of Laser Beam
Anatomy of the Ocean Surface Roughness
with Theory," J. Phys. Oceanogr. 13, 1505-1518, 1983. Tang, S. and O.H. Shemdin , "Measurement of High Frequency Waves Using a Wave Follower ," J...SAR 45 Paul A. Hwang 228-688-4708 Ocean surface roughness can be decomposed into an ambient component, surface wave geometric contribution (the mean...square slope), and breaking wave contribution (the breaking roughness). Only the last two components can be attributed to local wind conditions for
Dependence of Radar Backscatter on the Energetics of the Air-Sea Interface
481, pp. 142-148, 1984. Hsaio, and Shemdin , "Measurements of Wind Velocity and Pressure with a Wave Follower during MARSEN," J. Geophys. Res., v. 88...Corresponding Frequency Bounds of Region TV to Peak Energy in the Wave Height Spectrum) (from Shemdin and Hwang, 1988) Figure 10. 46 3) the surface drift range...discussed first, followed in turn by discussions of the observed effects of wind direction, long waves , atmospheric stratification and water
Decentralized Riemannian Particle Filtering with Applications to Multi-Agent Localization
USA, December 10-12 1997. 172 52. Brown, Robert G. and Patrick Y.C. Hwang. Introduction To Random Signals and Applied Kalman Filtering. John Wiley...London, 1994. 234. Randal Beard, Jonathan Lawton Wynn Stirling , Jacob Gunther. "Nonlinear Projec- tion Filter based on Galerkin Approximation". AIAA...Sensor Networks and Information Processing, 161 – 166. 2004. 242. Roberts , S. Reece S. "Robust, Low-Bandwidth, Multi-Vehicle Mapping". in Pro
Molecular Profiles for Lung Cancer Pathogenesis and Detection in U.S. Veterans
Risk level of individuals without lung cancer was calculated based on Bach model criteria (age, gender, smoking history and asbestos exposure) [19... deposited in miRBase release 17 as hsa-miR-4423, based on a small number of sequencing reads in studies that characterized the small RNA transcriptome of...All small RNA sequencing and microarray data has been deposited in GEO under the accession number GSE48798. References 1. Hwang HW, Mendell JT (2006
Model for surfactant-mediated growth of Ge on Pb-covered Si(111) surfaces
NASA Astrophysics Data System (ADS)
Bȩben, Janusz; Hwang, Ing-Shouh; Chang, Tien-Chih; Tsong, Tien T.
A model of surfactant-mediated epitaxy is investigated using the kinetic Monte Carlo method. This model assumes that (1) adatom-adatom interaction on the surfactant layer is weakly repulsive for dimers, and (2) a concerted atomic exchange of adatoms with surfactant atoms occurs when adatom clusters above the surfactant layer reach a threshold size. All essential features observed in a recent study of Ge/Pb/Si(111) reported by Hwang, Chang, and Tsong can be satisfactorily explained with this model.
Effects of Streamwise Pressure Gradients on Turbulence Structure in the Viscous Layer
Williams [1982]. An excellent review and assessment of the engineering applicability of the above three models was given by Hwang and Geib [1983...Taylor Research Center as Scientific Officer. Earlier incarnations were financed by the National Science Foundation ( Dr . Win Aung, Program Manager...developed and kindly provided by Dr . Michael Randolph, now of DFVLR/AVA, Gbttingen. At the Max Planck Institut fUr Str6mungsforschung -46- friendly
Bounds and Asymptotic Expansions for Solutions of the Free Boundary Problems Related to Sequential Decision Versions of a Bioequivalence Problem
the Free Boundary Problems Related to Sequential Decision Versions of a Bioequivalence Problem 12. PERSONAL AUTHOR(S) John Bather and Herman Chernoff...sequential version of a form of the bioequivalence problem was presented in a report by Hwang (1991). In that report he referred to our unpublished results...phrases. Bioequivalence , sequential anlaysis, Bayes risk, Brownian motion, free boundary problems, optimal stopping, asymptotic expansions. HARVARD
Defense Industry and Its Impacts on Economic Growth in Korea
is likely in Korea . Some argue that the Korean economy would have developed much faster without the burden of the defense spending. We could have...industry to the civilian industry in Korea . The intent of this study is to determine how much impact and influence the Korean defense industry has had...in Korea based on 1987 data. Dr. Dong J. Hwang studied the future of the Korean defense industry. But none of these authors studied the defense
Beyond Authoritarian Personality: The Culture-Inclusive Theory of Chinese Authoritarian Orientation
Chien, Chin-Lung
In a dyad interaction, respecting and obeying those with high status (authority) is highly valued in Chinese societies. Regarding explicit behaviors, Chinese people usually show respect to and obey authority, which we call authoritarian orientation. Previous literature has indicated that Chinese people have a high degree of authoritarian personality, which was considered a national character. However, under Confucian relationalism (Hwang, 2012a), authoritarian orientation is basically an ethical issue, and thus, should not be reduced to the contention of authoritarian personality. Based on Yang's (1993) indigenous conceptualization, Chien (2013) took an emic bottom-up approach to construct an indigenous model of Chinese authoritarian orientation; it represents a "culture-inclusive theory." However, Chien's model lacks the role of agency or intentionality. To resolve this issue and to achieve the epistemological goal of indigenous psychology (that is, "one mind, many mentalities"), this paper took the "cultural system approach" (Hwang, 2015b) to construct a culture-inclusive theory of authoritarian orientation in order to represent the universal mind of human beings as well as the mentalities of people in a particular culture. Two theories that reflect the universal mind, the "Face and Favor model" (Hwang, 1987) and the "Mandala Model of Self" (Hwang, 2011a,c), were used as analytical frameworks for interpreting Chien's original model. The process of constructing the culture-inclusive theory of authoritarian orientation may represent a paradigm for the construction of indigenous culture-inclusive theories while inspiring further development. Some future research directions are proposed herein. PMID:27445894
The Future of the United Nations Command in Republic of Korea
understanding my country, Korea. I also thank to Colonel Jung, Chan-Sung and Sergeant Major Moon, Byung -Nam in the United Nations Command in Korea for...engaged in some sharing of intelligence and technology. 24 It was very momentous that CDRCFC and his deputy, General Shin , who is a Korean 4 star...http://ebird.afis.osd.mil/ebfiles/e20031124aaindex.html>; Internet; accessed 24 February 2003. 22 Hwang, Byung -Moo. The peace of Korean peninsula in
Trojan Horse Attack Free Fault-Tolerant Quantum Key Distribution Protocols Using GHZ States
NASA Astrophysics Data System (ADS)
Chang, Chih-Hung; Yang, Chun-Wei; Hwang, Tzonelih
Recently, Yang and Hwang (Quantum Inf. Process. 13(3): 781-794, 19) proposed two fault-tolerant QKD protocols based on their proposed coding functions for resisting the collective noise, and their QKD protocols are free from Trojan horse attack without employing any specific detecting devices (e.g., photon number splitter (PNS) and wavelength filter). By using four-particle Greenberger-Horne-Zeilinger (GHZ) state and four-particle GHZ-like state in their proposed coding functions, Yang and Hwang's QKD protocols can resist each kind of the collective noise-collective-dephasing noise, collective-rotation noise. However, their proposed coding function can be improved by the utilization of three-particle GHZ state (three-particle GHZ-like state) instead of four-particle GHZ state (four-particle GHZ-like state) that will eventually reduce the consumption of the qubits. As a result, this study proposed the improved version of Yang and Hwang's coding functions to enhance the qubit efficiency of their schemes from 20 % to 22 %.
The Role of Traps in the Microstructural Control of Hydrogen Embrittlement of Steels.
Richards, Met. .4, Trans., 7A (1976), p. 821. 14. C. Hwang and l.M. Bernstein, Scriota Met., 17 (1983). Ij%15. P. Bastien and P. Azou , C.R. Acad. Sci. Paris...Conaress on Hvdroaen and Materials, Proc. 3rd Int'l Congress (P. Azou , eoa (1982) p. 491 28. A.R. Troiano, Trans. ASM, 52 (1960), p. 54. 29. R.A. Oriani, Ber...53 n. 7 (1982), p. 259. 44. K.W. Lange and H.J. Koning, 2nd Int. Conf. on Hydroaen in Metals, 1973, Paris (P. Azou , ed.) paper 1A5. 45. V.I. Saliv
Gain and Absorption Spectra of Quantum Wire Lasers Diodes Grown on Nonplanar Substrates
SIMMJ^ COMPONENT PART NOTICE THIS PAPER IS A COMPONENT PART OF THE FOLLOWING COMPILATION REPORT: TTT1F: Integrated Photonics Research. Volume 10...i't'y Co" .,.*» Dist kl Avji. :.;;fl,'or Spital ulll'MAR85Mb:> OPI: DTIC-TID Integrated Photonics Research -1 Gain and Absorption Spectra of...modulators and switches. 92-31749 Integrated Photonics Research 59 MC2-2 References: 1. E. Kapon, D.M. Hwang and R. Bhat, Phys. Rev. Lett. 63, 430 (1989
VizieR Online Data Catalog: Compact groups of galaxies from SDSS-DR12 (MLCG) (Sohn+, 2016)
NASA Astrophysics Data System (ADS)
Sohn, J.; Geller, M. J.; Hwang, H. S.; Zahid, H. J.; Lee, M. G.
We derive a sample of compact groups from the spectroscopic sample of SDSS DR12 (Alam et al. 2015ApJS..219...12A) galaxies at r<17.77. The DR12 includes redshifts for more than 2.4 million galaxies. To reduce the incompleteness of the SDSS, we supplement the catalog with redshifts from the literature (see Hwang et al. 2010A&A...522A..33H for details). We also add redshifts from recent FAST observations at Fred Lawrence Whipple Observatory (Sohn et al. 2015JKAS...48..381S). (8 data files).
Study of Desorption of Contaminant from Synthetic Soil
the sorption domain than the classical spherical or discrete distributions. A version of this model was tested by deVenoge (1996). The model was able...paraffin are reversible processes. The ability of the MSS model to predict geometry parameters was also tested . One finding of this study was the...HWANG TEST FOR MSSFIT:vials Medium RKD DEFF DPATH RLAM XSSO FAST 9.24 1.50E-08 0.249 2 19.74 0 ŕ means fit parameter, 0 means keep it fixed" 0 1 0 0
A Physiological Systems Approach to Modeling and Resetting of Mouse Thermoregulation under Heat Stress
RL. A whole body thermal model of man during hyperthermia. IEEE Trans Biomed Eng 34: 375–387, 1987. 3. Dematte JE, O'Mara K, Buescher J, Whitney CG...New York: Raven, 1992, p. 61–77. 4a.Fan L, Hsu F, and Hwang C. A review on mathematical models of the human thermal system. IEEE Trans Biomed Eng 18...radiation on metabolic heat production in a small desert rodent, Spermophilus tereticaudus. J Exp Biol 203: 879–888, 2000. 945MODELING OF MAMMALIAN
'We aren't quite as good, but we sure are cheap': prospects for disruptive innovation in medical care and insurance markets.
Pauly, Mark V
The concept of "disruptive innovation" by new products of moderately lower quality and much lower cost is useful for the medical care sector. Such products are rarely offered, and when they are (as in the case of health maintenance organizations), they are subject to intense criticism. This Perspective argues that both the legal system and accepted discourse in public policy have inhibited discussion of such alternatives; indeed, the paper by Jason Hwang and Clay Christensen loses its focus on them at the end. The applicability of this concept is quite limited but, given sufficient changes in framing and regulating, might be helpful in the future.
Widefield Two-Photon Excitation without Scanning: Live Cell Microscopy with High Time Resolution and Low Photo-Bleaching.
Amor, Rumelo; McDonald, Alison; Trägårdh, Johanna; Robb, Gillian; Wilson, Louise; Abdul Rahman, Nor Zaihana; Dempster, John; Amos, William Bradshaw; Bushell, Trevor J; McConnell, Gail
We demonstrate fluorescence imaging by two-photon excitation without scanning in biological specimens as previously described by Hwang and co-workers, but with an increased field size and with framing rates of up to 100 Hz. During recordings of synaptically-driven Ca(2+) events in primary rat hippocampal neurone cultures loaded with the fluorescent Ca(2+) indicator Fluo-4 AM, we have observed greatly reduced photo-bleaching in comparison with single-photon excitation. This method, which requires no costly additions to the microscope, promises to be useful for work where high time-resolution is required.
Risk Management Concepts and Guidance
Baillie, Allan S., "Management of Risk and Uncertainty," Research Management, Vol. 23, No. 2, March 1980, pp. 20-24. 34. Banash , Robert C., and...land, IL), 1976. 35. Banash , R.C., and Hurta, D.W., "Risk Analysis in Weapons Development," Proceedings of the 1972 U.S. Army Operations Research...Hwang, J.D., and Banash , R.C., "An Introduction to Decision/ Risk Analysis," (U.S. Army Armament Command), (Rock Island Arsenal), 1971 (LD 27240). 169
Stem cell research: cloning, therapy and scientific fraud.
Rusnak, A J; Chudley, A E
Stem cell research has generated intense excitement, awareness, and debate. Events in the 2005-2006 saw the rise and fall of a South Korean scientist who had claimed to be the first to clone a human embryonic stem cell line. From celebration of the potential use of stem cells in the treatment of human disease to disciplinary action taken against the disgraced scientists, the drama has unfolded throughout the world media. Prompted by an image of therapeutic cloning presented on a South Korean stamp, a brief review of stem cell research and the events of the Woo-suk Hwang scandal are discussed.
Molecular and Cellular Mechanisms for the Interaction between Gold Nanoparticles and Neuroimmune Cells Based on Size, Shape, and Charge
amplified products were resolved on a 1.8% agarose gel and visualized by ethidium bromide staining. The respective forward and reverse primers used for the...ranging from 2 to 12 nm had the maximum stimulatory activity for the production of antibody. References: [1] Dreaden E C, Alkilany A M, Huang...C, Hwang M T, Tsao J H and Mao S J 2006 J. Dairy . Sci. 89 912-21 [22] Klein U and Dalla-Favera R 2008 Nat. Rev. Immunol. 8 22-33 [23] Nutt S L
An Experimental Investigation of Wave Measurements Using a Dual-Beam Interferometer: Gulf Stream as a Surface Wave Guide
from fbr wave analysis. to be further explained in the following . v, and v,. respectively, or from S,& computed from v,. That I is] Of the three...INSAR ANALYSIS OF GULF STREAM WAVE GUIDE C09014 when the change of k following equation (13) is so large wave spectral analysis, a 3 x 3-pixel smoothing...Hwang anUd lie, Y., and W. Alpers (20013), On the nonlinear integral transform of an Shemdin , 19901 and equation (B4) is identically the ocean wave
Development of Yeast as an In Vivo Test Tube to Characterize a Broad Spectrum of p53 Mutations Associated with Breast Cancer
RESULTS a new set of isogenic haploid yeast strains based upon the RADE2 red-white p53 reporter system initially described by Fla- Development of a panel of...diverse p53- dependent responses, which has implications for cancer sus- ACKNOWLEDGMENTS ceptibility and evolution . Our thanks go to Richard Iggo for the...673-682. 78. Wahl, G. M., and A. M. Carr. 2001. The evolution of diverse biological 85. Yu, J., L. Zhang, P. M. Hwang, C. Rago, K. W. Kinzier, and B
Origin of Charge Density at LaAlO3 on SrTiO3 Heterointerfaces: Possibility of Intrinsic Doping
Siemons, W.; Koster, Gertjan; Yamamoto, Hideki; Harrison, Walter A.; Lucovsky, Gerald; Geballe, Theodore H.; Blank, Dave H.A.; Beasley, Malcolm R.; /Stanford U., Geballe Lab.
As discovered by Ohtomo and Hwang, a large sheet charge density with high mobility exists at the interface between SrTiO{sub 3} and LaAlO{sub 3}. Based on transport, spectroscopic, and oxygen-annealing experiments, we conclude that extrinsic defects in the form of oxygen vacancies introduced by the pulsed laser deposition process used by all researchers to date to make these samples is the source of the large carrier densities. Annealing experiments show a limiting carrier density. We also present a model that explains the high mobility based on carrier redistribution due to an increased dielectric constant.
Students' conceptions: culturing conceptions
NASA Astrophysics Data System (ADS)
Tiberghien, Andrée
This commentary on Roth, Lee, and Hwang's paper aims at analysing their theoretical approach in terms of its object of study, and the aspects that are brought to the fore, like the cultural activity of conversation, and those that are overshadowed, like the role of the material world and its perception on learning. This analysis, developed on the basis of a pragmatic approach that combines theoretical frameworks, leads to a debate about the relevant components of teaching-learning situations according to the theoretical approaches, and the extent to which, due to the complexity of the studied phenomena, some theoretical frameworks are complementary or concurrent.
Research ethics and lessons from Hwanggate: what can we learn from the Korean cloning fraud?
Saunders, R; Savulescu, J
In this review of the Korean cloning scandal involving Woo-Suk Hwang, the nature of the disaster is documented and reasons why it occurred are suggested. The general problems it raises for scientific research are highlighted and six possible ways of improving practice are offered in the light of this case: (1) better education of science students; (2) independent monitoring and validation; (3) guidelines for tissue donation for research; (4) fostering of debate about ethically contentious research in science journals; (5) development of an international code of ethical research practice; (6) fostering of public involvement in ethical review and debate through the web.
Widefield Two-Photon Excitation without Scanning: Live Cell Microscopy with High Time Resolution and Low Photo-Bleaching
Amor, Rumelo; McDonald, Alison; Trägårdh, Johanna; Robb, Gillian; Wilson, Louise; Abdul Rahman, Nor Zaihana; Dempster, John; Amos, William Bradshaw; Bushell, Trevor J.; McConnell, Gail
We demonstrate fluorescence imaging by two-photon excitation without scanning in biological specimens as previously described by Hwang and co-workers, but with an increased field size and with framing rates of up to 100 Hz. During recordings of synaptically-driven Ca2+ events in primary rat hippocampal neurone cultures loaded with the fluorescent Ca2+ indicator Fluo-4 AM, we have observed greatly reduced photo-bleaching in comparison with single-photon excitation. This method, which requires no costly additions to the microscope, promises to be useful for work where high time-resolution is required. PMID:26824845
Compact Broad-Band Wavelength-Agile Mid-Infrared Semiconductor Lasers for Spectroscopic Sensing
IEEE Photon. Technol. Lett. Jan 2005). Yi Wang, Chuan Peng, HuanLin Zhang, and Han Q. Le, "Wavelength modulation imaging with tunable mid- infrared...Wen-Yen Hwang, Jae Um, Bujin Guo, Hao Lee, and Chih- Hsiang Lin, "Continuous-wave operation of a 5.2 µm quantum-cascade laser up to 210 K", Appl. Phys...Lett. 79, 1745-1747, (2001). 2. Proceedings Yi Wang, Yang Wang, Chuan Peng, HuanLin Zhang, Anush Seetheraman, and Han Q. Le, "Concepts for Scalable
Anomalous Insulator-Metal Transition in Boron Nitride-Graphene Hybrid Atomic Layers
locally centered atomic or- bital (LCAO) basis set, and the Perdew-Burke-Ernzerhof (PBE) exchange- correlation functional.36 The occupation of the Kohn-Sham...Stausholm-Møller, M. Strange, G. A. Tritsaris, M. Vanin, M. Walter, B. Hammer , H. Häkkinen, G. K. H. Madsen, R. M. Nieminen, J. K. Nørskov, M. Puska, T. T... Schmidt , and M. Martin, Nat. Mater. 7, 391 (2008). 43V. M. Pudalov, JETP Lett. 66, 175 (1997). 44S. Das Sarma and E. H. Hwang, Phys. Rev. Lett. 83, 164
East China Sea Kuroshio 2002-2004 Data Report. Part 1. The URI/JAMSTEC Measurements. Part 2. The SNU/KORDI Measurements
KORDI Measurements Magdalena Andres1† Chang-Su Hong3* Jae-Hak Lee3* Byung -Ho Lim2* Jae-Hun Park1† Karen Tracey1† Mark Wimbush1† Kyung-Il Chang2...acknowledge the help of Mr. Sang- Chul Hwang and Young-Suk Jang from KORDI with the instrumentation and, especially, their dedication and support during the...mooring operations on all these cruises. We would also like to acknowledge the help of Professors Jae- Chul Lee and Mi-Ok Park, and their students at
Extended yrast level schemes in ^121,123Cd
NASA Astrophysics Data System (ADS)
Walters, W. B.; Chiara, C. J.
New level structures for ^121,123Cd will be presented that were determined in the study of the ^64Ni- and ^76Ge-induced fission of ^238U at Gammasphere [1]. A number of transitions were previously observed by Hwang et al. from which yrast levels were identified with maximum proposed spins of 27/2- and 23/2- in ^121,123Cd, respectively [2]. If the additional transitions have stretched E2 multipolarity, these level structures would be extended to 31/2- at 4083 keV, and 35/2- at 5365 keV in ^121,123Cd, respectively. These level sequences will be compared to existing levels in the lighter odd-mass Cd nuclei and the isomeric structures and calculations in the heavier odd-mass Cd nuclei.[4pt] [1] C. J. Chiara, I. Stefanescu, A. A. Hecht, R. V. F. Janssens, W. B. Walters, R. Broda, M. P. Carpenter, B. Fornal, G. Gúrdal, C. R. Hoffman, N. Hoteling, B. P. Kay, F. G. Kondev, W. Kr'olas, T. Lauritsen, C. J. Lister, E. A. McCutchan, T. Pawlat, D. Seweryniak, N. Sharp, J. R. Stone, N. J. Stone, X. Wang, A. Wóhr, J. Wrzesinski, S. Zhu, to be submitted for publication in Phys. Rev. C.[0pt] [2] J. K. Hwang et al., J. Phys. G: Nucl. Part. Phys. 28, L9 (2002).
Efficient multiparty quantum-secret-sharing schemes
Xiao Li; Deng Fuguo; Long Guilu; Pan Jianwei
In this work, we generalize the quantum-secret-sharing scheme of Hillery, Buzek, and Berthiaume [Phys. Rev. A 59, 1829 (1999)] into arbitrary multiparties. Explicit expressions for the shared secret bit is given. It is shown that in the Hillery-Buzek-Berthiaume quantum-secret-sharing scheme the secret information is shared in the parity of binary strings formed by the measured outcomes of the participants. In addition, we have increased the efficiency of the quantum-secret-sharing scheme by generalizing two techniques from quantum key distribution. The favored-measuring-basis quantum-secret-sharing scheme is developed from the Lo-Chau-Ardehali technique [H. K. Lo, H. F. Chau, and M. Ardehali, e-print quant-ph/0011056] where all the participants choose their measuring-basis asymmetrically, and the measuring-basis-encrypted quantum-secret-sharing scheme is developed from the Hwang-Koh-Han technique [W. Y. Hwang, I. G. Koh, and Y. D. Han, Phys. Lett. A 244, 489 (1998)] where all participants choose their measuring basis according to a control key. Both schemes are asymptotically 100% in efficiency, hence nearly all the Greenberger-Horne-Zeilinger states in a quantum-secret-sharing process are used to generate shared secret information.
The Process of Self-Cultivation and the Mandala Model of the Self
Wu, Meiyao
In his Mandala model of the self, Taiwanese scholar Kwang-Kuo Hwang sees each human being as a combination or intersection of private individual and social person, and also of knowledge and action. To further elaborate the model—with a particular emphasis on teaching/learning, the development of the ideal self and spiritual transcendence—this article will explore the psychological process of self-cultivation in the light of traditional Confucian thinking, which means keeping a balance between inner/outer and self/other. The Neo-Confucian thinker Zhongsha Mou's theories of "the awareness of unexpected developments" and his meditation/cognitive thinking opposition will also be discussed. The analyzed sources will include the traditional Confucian classics (the Four Books and Liji, or Classic of Rites) and especially the "Lessons for Learning (Xue-Ji)" in the Classic of Rites (Liji), along with the relevant textual research. Based upon a cultural-semantic analysis of these classics as well as of Hwang's central ideas, the author attempts to further conceptualize the process of cultivating the ideal self in Confucian education1. PMID:28174544
A role for seed storage proteins in Arabidopsis seed longevity.
Nguyen, Thu-Phuong; Cueff, Gwendal; Hegedus, Dwayne D; Rajjou, Loïc; Bentsink, Leónie
Proteomics approaches have been a useful tool for determining the biological roles and functions of individual proteins and identifying the molecular mechanisms that govern seed germination, vigour and viability in response to ageing. In this work the dry seed proteome of four Arabidopsis thaliana genotypes, that carry introgression fragments at the position of seed longevity quantitative trait loci and as a result display different levels of seed longevity, was investigated. Seeds at two physiological states, after-ripened seeds that had the full germination ability and aged (stored) seeds of which the germination ability was severely reduced, were compared. Aged dry seed proteomes were markedly different from the after-ripened and reflected the seed longevity level of the four genotypes, despite the fact that dry seeds are metabolically quiescent. Results confirmed the role of antioxidant systems, notably vitamin E, and indicated that protection and maintenance of the translation machinery and energy pathways are essential for seed longevity. Moreover, a new role for seed storage proteins (SSPs) was identified in dry seeds during ageing. Cruciferins (CRUs) are the most abundant SSPs in Arabidopsis and seeds of a triple mutant for three CRU isoforms (crua crub cruc) were more sensitive to artificial ageing and their seed proteins were highly oxidized compared with wild-type seeds. These results confirm that oxidation is involved in seed deterioration and that SSPs buffer the seed from oxidative stress, thus protecting important proteins required for seed germination and seedling formation.
A role for seed storage proteins in Arabidopsis seed longevity
Nguyen, Thu-Phuong; Cueff, Gwendal; Hegedus, Dwayne D; Rajjou, Loïc; Bentsink, Leónie
Proteomics approaches have been a useful tool for determining the biological roles and functions of individual proteins and identifying the molecular mechanisms that govern seed germination, vigour and viability in response to ageing. In this work the dry seed proteome of four Arabidopsis thaliana genotypes, that carry introgression fragments at the position of seed longevity quantitative trait loci and as a result display different levels of seed longevity, was investigated. Seeds at two physiological states, after-ripened seeds that had the full germination ability and aged (stored) seeds of which the germination ability was severely reduced, were compared. Aged dry seed proteomes were markedly different from the after-ripened and reflected the seed longevity level of the four genotypes, despite the fact that dry seeds are metabolically quiescent. Results confirmed the role of antioxidant systems, notably vitamin E, and indicated that protection and maintenance of the translation machinery and energy pathways are essential for seed longevity. Moreover, a new role for seed storage proteins (SSPs) was identified in dry seeds during ageing. Cruciferins (CRUs) are the most abundant SSPs in Arabidopsis and seeds of a triple mutant for three CRU isoforms (crua crub cruc) were more sensitive to artificial ageing and their seed proteins were highly oxidized compared with wild-type seeds. These results confirm that oxidation is involved in seed deterioration and that SSPs buffer the seed from oxidative stress, thus protecting important proteins required for seed germination and seedling formation. PMID:26184996
Data for identification of porcine X-chromosome inactivation center, XIC, by genomic comparison with human and mouse XIC
Hwang, Jae Yeon; Choi, Kwang-Hwan; Lee, Chang-Kyu
The data included in this article shows homologies of genes in porcine X-chromosome inactivation center, XIC, to each orthologue in human and mouse XIC. Open sequences of XIC-linked genes in human and mouse were compared to porcine genome and sequence homology of each orthologue to porcine genome was calculated. Sequence information of porcine genes encoded in the genomic regions having sequence homology with the human XIC-linked genes and their 2 Kb upstream regions were downloaded. Obtained information was used to design primer pairs for expression and methylation pattern analyses of XIC-linked genes in pigs. The data represented in here is related and applied to the research article entitled "Dosage compensation of X-chromosome inactivation center, XIC,-linked genes in porcine preimplantation embryos: Non-chromosome wide initiation of X-chromosome inactivation in blastocysts", published in Mechanisms of Development Hwang et al., 2015 [1]. PMID:26793753
Data for identification of porcine X-chromosome inactivation center, XIC, by genomic comparison with human and mouse XIC.
Hwang, Jae Yeon; Choi, Kwang-Hwan; Lee, Chang-Kyu
The data included in this article shows homologies of genes in porcine X-chromosome inactivation center, XIC, to each orthologue in human and mouse XIC. Open sequences of XIC-linked genes in human and mouse were compared to porcine genome and sequence homology of each orthologue to porcine genome was calculated. Sequence information of porcine genes encoded in the genomic regions having sequence homology with the human XIC-linked genes and their 2 Kb upstream regions were downloaded. Obtained information was used to design primer pairs for expression and methylation pattern analyses of XIC-linked genes in pigs. The data represented in here is related and applied to the research article entitled "Dosage compensation of X-chromosome inactivation center, XIC,-linked genes in porcine preimplantation embryos: Non-chromosome wide initiation of X-chromosome inactivation in blastocysts", published in Mechanisms of Development Hwang et al., 2015 [1].
Doping and Hall effect in SrTiO3
NASA Astrophysics Data System (ADS)
Stemmer, Susanne
Electron-doped SrTiO3 has generated renewed interest because of reports of coexisting magnetism and superconductivity, and of superconducting transitions at extremely low carrier densities. In this talk, we will present new insights into doping and its electronic structure obtained using very high quality SrTiO3 films grown by molecular beam epitaxy. We discuss the arrangements and imaging of individual La dopant atoms and clusters using quantitative scanning transmission electron microscopy. We present studies of the temperature dependence of the Hall coefficient, Hall mobility, and of Shubnikov-de Haas oscillations. We will particularly discuss the significance of the regime in which the resistance follows a T2 temperature-dependence over a wide range of temperatures and doping. This work was performed in collaboration with Evgeny Mikheev, Adam Kajdos, Jinwoo Hwang, Jack Zhang, and Jim Allen.
Oxygen and Fuel Jet Diffusion Flame Studies in Microgravity Motivated by Spacecraft Oxygen Storage Fire Safety
NASA Technical Reports Server (NTRS)
Sunderland, P. B.; Yuan, Z.-G.; Krishnan, S. S.; Abshire, J. M.; Gore, J. P.
Owing to the absence of past work involving flames similar to the Mir fire namely oxygen-enhanced, inverse gas-jet diffusion flames in microgravity the objectives of this work are as follows: 1. Observe the effects of enhanced oxygen conditions on laminar jet diffusion flames with ethane fuel. 2. Consider both earth gravity and microgravity. 3. Examine both normal and inverse flames. 4. Compare the measured flame lengths and widths with calibrated predictions of several flame shape models. This study expands on the work of Hwang and Gore which emphasized radiative emissions from oxygen-enhanced inverse flames in earth gravity, and Sunderland et al. which emphasized the shapes of normal and inverse oxygen-enhanced gas-jet diffusion flames in microgravity.
Finite difference method for solving the Schroedinger equation with band nonparabolicity in mid-infrared quantum cascade lasers
Cooper, J. D.; Valavanis, A.; Ikonic, Z.; Harrison, P.; Cunningham, J. E.
The nonparabolic Schroedinger equation for electrons in quantum cascade lasers (QCLs) is a cubic eigenvalue problem (EVP) which cannot be solved directly. While a method for linearizing this cubic EVP has been proposed in principle for quantum dots [Hwang et al., Math. Comput. Modell., 40, 519 (2004)] it was deemed too computationally expensive because of the three-dimensional geometry under consideration. We adapt this linearization approach to the one-dimensional geometry of QCLs, and arrive at a direct and exact solution to the cubic EVP. The method is then compared with the well established shooting method, and it is shown to be more accurate and reliable for calculating the bandstructure of mid-infrared QCLs.
Cryptanalysis on a scheme to share information via employing a discrete algorithm to quantum states
NASA Astrophysics Data System (ADS)
Amellal, H.; Meslouhi, A.; El Baz, M.; Hassouni, Y.; El Allati, A.
Recently, Yang and Hwang [Int. J. Theor. Phys. 53, 224 (2014)] demonstrated that the scheme to share information via employing discrete algorithm to quantum states presented by Kang and Fang [Commun. Theor. Phys. 55, 239 (2011)] suffers from a major vulnerability allowing an eavesdropper to perform a measurement and resend attack. By introducing an additional checking state framework, the authors have proposed an improved protocol to overcome this weakness. This work calls into question the invoked vulnerability in order to clarify a misinterpretation in the same protocol stages also introduce a possible leakage information strategy, known as a faked state attack, despite the proposed improvement, which means that the same security problem may persist. Finally, an upgrading technic was introduced in order to enhance the security transmission.
Volatilization of selected organic compounds from a creosote-waste land-treatment facility. Master's thesis
Scott, E.J.
The purpose of this research was to evaluate the emissions of volatile and semi-volatile compounds which are constituents of a complex creosote waste from laboratory simulations of a land treatment system to assess the potential human exposure to hazardous compounds from this source. In addition, the Thibodeaux-Hwang Air Emission Release Rate (AERR) model was evaluated for its use in predicting emission rates of hazardous constituents of creosote wood preservative waste from land treatment facilities. A group of hazardous volatile and semi-volatile constituents present in the creosote waste was selected for evaluation in this study and included a variety of polynuclear aromatic hydrocarbons (PNA's), phenol, and chlorinated and substituted phenols.
A note on static spaces and related problems
NASA Astrophysics Data System (ADS)
Qing, Jie; Yuan, Wei
In this paper we study static spaces introduced in Hawking and Ellis (1975) [1], Fischer and Marsden (1975) [3] and Riemannian manifolds possessing solutions to the critical point equation introduced in Besse (1987) [11], Hwang (2000) [12]. In both cases, on the manifolds there is a function satisfying a particular Ricci-Hessian type equation (1.6). With an idea similar to that used in Cao et al. (2012) [15,16], we have made progress in solving the problem raised in Fischer and Marsden (1975) [3] of classifying vacuum static spaces and in proving the conjecture proposed in Besse (1987) [11] concerning manifolds admitting solutions to the critical point equation in general dimensions. We obtain even stronger results in dimension 3.
VizieR Online Data Catalog: PACS Evolutionary Probe (PEP-DR1) catalogs (Lutz+, 2011)
NASA Astrophysics Data System (ADS)
Lutz, D.; Poglitsch, A.; Altieri, B.; Andreani, P.; Aussel, H.; Berta, S.; Bongiovanni, A.; Brisbin, D.; Cava, A.; Cepa, J.; Cimatti, A.; Daddi, E.; Dominguez-Sanchez, H.; Elbaz, D.; Foerster Schreiber, N. M.; Genzel, R.; Grazian, A.; Gruppioni, C.; Harwit, M.; Le Floc'h, E.; Magdis, G.; Magnelli, B.; Maiolino, R.; Nordon, R.; Perez Garcia, A. M.; Popesso, P.; Pozzi, F.; Riguccini, L.; Rodighiero, G.; Saintonge, A.; Sanchez Portal, M.; Santini, P.; Shao, L.; Sturm, E.; Tacconi, L. J.; Valtchanov, I.; Wetzstein, M.; Wieprecht, E.
PACS catalogs built by the PEP team, with key contributions by Stefano Berta, Benjamin Magnelli, Paola Popesso, Dieter Lutz, Francesca Pozzi, Bruno Altieri, Herve Aussel, Hoseong Hwang, Emeric Le Floc'h, Georgios Magdis, Raanan Nordon, Albrecht Poglitsch, Laurie Riguccini, Amelie Saintonge, Li Shao. For more details, please refer to Lutz et al. (2011A&A...532A..90L) and to the PDF documentation associated to the release. Data and catalogs can be retrieved from the web page http://www.mpe.mpg.de/ir/Research/PEP/publicdatareleases.php See the PDF documentation associated to the PEP DR1 release, http://www.mpe.mpg.de/resources/PEP/DR1tarballs/readmePEP_global.pdf and http://www.mpe.mpg.de/resources/PEP/DR1tarballs/readmePEP_SPIRE.pdf for more details. (69 data files).
Bauer, Siegfried; Kaltenbrunner, Martin
Microelectronics dominates the technological and commercial landscape of today's electronics industry; ultrahigh density integrated circuits on rigid silicon provide the computing power for smart appliances that help us organize our daily lives. Integrated circuits function flawlessly for decades, yet we like to replace smart phones and tablet computers every year. Disposable electronics, built to disappear in a controlled fashion after the intended lifespan, may be one of the potential applications of transient single-crystalline silicon nanomembranes, reported by Hwang et al. in this issue of ACS Nano. We briefly outline the development of this latest branch of electronics research, and we present some prospects for future developments. Electronics is steadily evolving, and 20 years from now we may find it perfectly normal for smart appliances to be embedded everywhere, on textiles, on our skin, and even in our body.
Magnetic control of ferroelectric interfaces
NASA Astrophysics Data System (ADS)
Dussan, S.; Kumar, A.; Katiyar, R. S.; Priya, S.; Scott, J. F.
We report the strong magnetic field dependence of ferroelectric PbZr0.52Ti0.48O3 (PZT) films on half-metallic oxide La0.67Sr0.33MnO3 (LSMO) electrodes. As the field H is increased, the hysteresis loop first broadens (becomes lossy) and then disappears at approximately H = 0.34 T and ambient temperatures. The data are compared with the theories of Pirč et al (2009 Phys. Rev. B 79 214114), Parish and Littlewood (2008 Phys. Rev. Lett. 101 166602) and Catalan (2006 Appl. Phys. Lett. 88 102902). The results are interpreted as due not to magnetocapacitance but to the sharp negative magnetoresistance in LSMO at low magnetic fields (Hwang et al 1996 Phys. Rev. Lett. 77 2041), which causes a dramatic increase in leakage current through the PZT.
Excited-state quantum phase transition in the Rabi model
NASA Astrophysics Data System (ADS)
Puebla, Ricardo; Hwang, Myung-Joong; Plenio, Martin B.
The Rabi model, a two-level atom coupled to a harmonic oscillator, can undergo a second-order quantum phase transition (QPT) [M.-J. Hwang et al., Phys. Rev. Lett. 115, 180404 (2015), 10.1103/PhysRevLett.115.180404]. Here we show that the Rabi QPT accompanies critical behavior in the higher-energy excited states, i.e., the excited-state QPT (ESQPT). We derive analytic expressions for the semiclassical density of states, which show a logarithmic divergence at a critical energy eigenvalue in the broken symmetry (superradiant) phase. Moreover, we find that the logarithmic singularities in the density of states lead to singularities in the relevant observables in the system such as photon number and atomic polarization. We corroborate our analytical semiclassical prediction of the ESQPT in the Rabi model with its numerically exact quantum mechanical solution.
Brow archetype preferred by Korean women.
Kim, Seong Kee; Cha, Seung Hyun; Hwang, Kun; Hwang, Se Won; Kim, Young Suk
The aim of this study is to see which brow archetype is preferred by Korean women. The archetypes were chosen from a literature search, which contain detailed, replicable methods and have diagrams (Westmore, Lamas, Anastasia, Schreiber, and Hwang). A survey was conducted on 300 subjects (group A, 100 female medical students; group B, 100 women who had visited a plastic surgery clinic for periorbital rejuvenation; and group C, 100 women who visited the brow bar). They were asked whether they think there might be a method that yields an ideal brow archetype. In the cases where they said yes, they were asked to choose 1 of the illustrated 5 brow archetypes that they think is ideal. Among the 300 respondents, 232 (77.3%) thought there might be a method to yield an ideal brow archetype, whereas 68 (22.7%) answered they did not. The preference for the brow archetypes was different among the 5 archetypes (P = 0.0001, χ2). Anastasia was the most preferred (44.8%, brow starts on a perpendicular line drawn from the middle of the nostril, arches on a line drawn from the center of the nose through the center of the pupil, and ends on a line drawn from the edge of the corresponding nasal ala through the outer edge of the eye). Anastasia was followed by Lamas (22.0%). In group A, Anastasia (55.7%) was the most preferred, followed by Lamas (26.2%) and Westmore (13.1%). In group B, Anastasia (34.8%) was the most preferred, followed by Lamas (30.3%) and Westmore and Schreiber (both 13.5%). In group C, Anastasia (47.6%) was the most preferred, followed by Hwang (25.5%) and Westmore (11.0%). There was a significant difference (P < 0.001) among the 3 groups. There was a significant correlation between the preference of brow archetype and occupation (P = 0.0033). However, no significant differences were noted for the preference of brow archetype between the age groups of younger than 30 years and older than 30 years (P = 0.1374), level of education (P = 0.3403), marital status (P = 0
Correlation driven charge order at LaAlO3/SrTiO3 and LaTiO3/SrTiO3 Interfaces
NASA Astrophysics Data System (ADS)
Pentcheva, Rossitza
Correlated behavior at complex oxide interfaces offers additional degrees of freedom to compensate charge imbalance not available e.g. in polar semiconductor heterostructures. This can result in electronic, charge and magnetic phases that do not exist in the bulk and offers new possibilities for device applications. For instance, the interfaces of LaTiO3 and SrTiO3 [1] as well as LaAlO3 and SrTiO3 [2] show metallic conductivity, although the respective bulk materials are Mott (LTO) and band insulating (STO, LAO). Here we present the results of material-specific correlated band theory (LDA+U) employing the FP-LAPW code in the WIEN2k implementation for a variety of (n,m) multilayers containing n LTO (or LAO) and m STO-layers. To explore the relaxation length towards bulk behavior n and m is varied between 1 and 9. We find that charge mismatch at the LTO/STO IF is accommodated by the formation of a charge and orbitally ordered (CO/OO) layer with a checkerboard arrangement of Ti^3+ and Ti^4+ and an antiferromagnetic coupling of the Ti^3+-spins [3]. Lattice relaxations lead to the observed conducting behavior. An analogous diluted layer of Ti^3+ spins is obtained for the n-type LAO/STO interface, although the corresponding bulk materials are nonmagnetic. For a structurally ideal p-type LAO/STO IF the measured insulating behavior can only be understood by a charge disproportionation on the oxygen sublattice and the formation of a CO/OO magnetic OPπ hole. Alternatively, charge compensation by oxygen vacancies and the formation of a charge conjugate F-center is considered. [1] A. Ohtomo, and H.Y. Hwang, Nature 423, 378 (2002). [2] A. Ohtomo, D.A. Muller, J.L. Grazul, and H.Y. Hwang, Nature 419, 378 (2002). [3] R. Pentcheva and W.E. Pickett, cond-mat/0608212. [4] R. Pentcheva and W.E. Pickett, Phys. Rev. B 74, 035112 (2006).
The linear and nonlinear Rayleigh Taylor instability for the quasi-isobaric profile
NASA Astrophysics Data System (ADS)
Lafitte, Olivier
We study the 2D system of incompressible gravity driven Euler equations in the neighborhood of a particular smooth density profile ρ0(x) such that ρ0(x)=ρaξ({x}/{L0}), where ξ is a nonconstant solution of ξ˙=ξ(1-ξ), L0>0 is the width of the ablation region, ν>1 is the thermal conductivity exponent, and ρa>0 is the maximum density of the fluid. The linearization of the equations around the stationary solution (ρ0,0→,p0), ∇p0=ρ0g→ leads to the study of the Rayleigh equation for the perturbation of the velocity at the wavenumber k: -{d}/{dx}(ρ0(x){dubar }/{dx})+k2(ρ0(x)-{g}/{γ2}ρ0‧(x))ubar =0. We denote by the terms 'eigenmode and growth rate' an L2(R) solution of the Rayleigh equation associated with a value of γ. The purpose of this paper is twofold: derive the following expansion in kL0, for small kL0, of the unique reduced linear growth rate {γ}/{√{gk}}∈[{1}/{4},1] {gk}/{γ2}=1+{2}/{Γ(1+1/ν})(+a2(+O(kL0) where a2 is explicitly known, provided ν>2, prove the nonlinear instability result for small times in the neighborhood of a general profile ρ0(x) such that k0(x)={ρ}/{0‧(x)ρ0(x)} is regular enough, bounded, and k0(x)( bounded (which is the case for ρaξ({x}/{L0})), thanks to the existence of Λ such that γ≤Λ for all possible growth rates and at least one growth rate γ belongs to ({Λ}/{2},Λ). This generalizes the result of Guo and Hwang [Y. Guo, H.J. Hwang, On the dynamical Rayleigh-Taylor instability, Arch. Ration. Mech. Anal. 167 (3) (2003) 235-253], which was obtained in the case ρ0(x)≥ρl>0.
Hydrostatic pressure response of an oxide-based two-dimensional electron system
NASA Astrophysics Data System (ADS)
Zabaleta, J.; Borisov, V. S.; Wanke, R.; Jeschke, H. O.; Parks, S. C.; Baum, B.; Teker, A.; Harada, T.; Syassen, K.; Kopp, T.; Pavlenko, N.; Valentí, R.; Mannhart, J.
Two-dimensional electron systems with fascinating properties exist in multilayers of standard semiconductors, on helium surfaces, and in oxides. Compared to the two-dimensional (2D) electron gases of semiconductors, the 2D electron systems in oxides are typically more strongly correlated and more sensitive to the microscopic structure of the hosting lattice. This sensitivity suggests that the oxide 2D systems are highly tunable by hydrostatic pressure. Here we explore the effects of hydrostatic pressure on the well-characterized 2D electron system formed at LaAlO3-SrTiO3 interfaces [A. Ohtomo and H. Y. Hwang, Nature (London) 427, 423 (2004), 10.1038/nature02308] and measure a pronounced, unexpected response. Pressure of ˜2 GPa reversibly doubles the 2D carrier density ns at 4 K. Along with the increase of ns, the conductivity and mobility are reduced under pressure. First-principles pressure simulations reveal the same behavior of the carrier density and suggest a possible mechanism of the mobility reduction, based on the dielectric properties of both materials and their variation under external pressure.
Role of Atmospheric Transport on the Arctic Amplification: Adjusting Role
NASA Astrophysics Data System (ADS)
KUG, J.; Yim, B.; Jin, F.
It is controversial whether the atmospheric transport plays a role in arctic amplification. Recently, Hwang et al. (2011) showed that the magnitude of the arctic amplification is negatively correlated with anomalous poleward atmospheric transport. That is, when the arctic amplification is strong (weak), the atmospheric transport plays a negative (positive) role in the arctic amplification. In this study, it is discussed what is a physical mechanism to determine the role of atmospheric transport and relation with the arctic amplification. Here, we suggest adjusting roles of atmospheric transport. The strength of local feedback over the Arctic determines zonal wind changes. The zonal wind changes are determined by two factors. The first one is polar cap cooling, and second is surface warming. They play opposite roles. So, there will be two different zonal wind responses in high-latitude to the greenhouse warming. Depending on the zonal wind response, the atmospheric transport can play a different role because the zonal wind changes can organize synoptic eddy feedbacks including heat flux, which largely contributes to poleward energy transport. We show here that when polar cap cooling is strong, and surface warming over Arctic is relatively weak, the Jet stream tends to be shifted poleward, so it leads to poleward atmospheric transport. On the other hand, when the surface warming is too strong, it lead to southward shift of Jet stream and equatorward atmospheric transport, which paly a negative role in the Arctic amplification.
Enhanced chondrogenic differentiation of murine embryonic stem cells in hydrogels with glucosamine.
Hwang, Nathaniel S; Varghese, Shyni; Theprungsirikul, Parnduangjai; Canver, Adam; Elisseeff, Jennifer
Differentiation of embryonic stem (ES) cells generally occurs after formation of three-dimensional cell aggregates, known as embryoid bodies (EBs). We have previously reported that hydrogels provide EBs a supportive environment for in vitro chondrogenic differentiation and three dimensional tissue formation [Hwang NS, et al. The Effects of three dimensional culture and growth factors on the chondrogenic differentiation of murine ES cells. Stem Cells 2006;24:284-91]. In this study, we report chondrogenic differentiation of murine ES cells encapsulated in photopolymerizing poly(ethylene-glycol)-based (PEG) hydrogels in the presence of glucosamine (GlcN), an amino monosaccharide found in chitin, glycoproteins and glycosaminoglycans such as hyaluronic acid, chondroitin sulfate and heparin sulfate. We examined the growth and differentiation of encapsulated EBs in standard chondrogenic differentiation medium containing 0-, 2-, and 10-mm GlcN. Morphometric analysis and examination of gene and protein expression indicated that treatment of hydrogel cultures with 2-mm GlcN for 21 days significantly increased EB size, levels of aggrecan mRNA, and tissue-specific extracellular matrix accumulation. GlcN can induce multiple aspects of cell behavior and optimal GlcN concentrations can be beneficial for directing the differentiation and tissue formation of ES cells.
Theory of band alignment at the LaAlO3/SrTiO3 interface
NASA Astrophysics Data System (ADS)
Lee, Jaekwang; Demkov, Alex
A polar discontinuity at the abrupt oxide/oxide interface is one of several problems that need to be addressed before we can realize the promise of multiferroic oxide structures. To avoid the so-called polar catastrophe the interface undergoes roughening which renders the structure useless, unless the system finds a mechanism for compensating the interface charges. Recent experiments of Hwang and co-workers (Nature 427, 423-426 (2004) and Nature 430, 657-661 (2004)) suggest that in the case of perovskite oxides two quite different compensatory mechanisms are at play at the heterojunction. For the n-type LaAlO3/SrTiO3 interface it is purely electronic involving mixed valence Ti ions, while for the p-type it is an actual ionic reconstruction involving oxygen vacancies. We report a first-principles study of both interfaces within density functional theory. We consider the energetics and electronic structure of the interface, including the role of oxygen vacancies and band offsets. In addition we consider the interface stability with respect to inter diffusion of La and Sr across the interface.
Chasing a polar catastrophe: ab-initio theory of the LaAlO3/SrTiO3 interface
NASA Astrophysics Data System (ADS)
Lee, Jaekwang; Demkov, A. A.
A polar discontinuity at the abrupt oxide/oxide interface is one of several problems that need to be addressed before we can realize the promise of multiferroic oxide structures. To avoid the so-called polar catastrophe the interface undergrows roughening which renders the structure useless, unless the system finds a mechanism for compensating the interface charges. Recent experiments of Hwang and co-workers (Nature 427, 423-426 (2004) and Nature 430, 657-661 (2004)) suggest that in the case of perovskite oxides two quite different compensatory mechanisms are at play at the heterojunction. For the n-type LaAlO3/SrTiO3 interface it is purely electronic involving mixed valence Ti ions, while for the p-type it is an actual ionic reconstruction involving oxygen vacancies. We report a first-principles study of both interfaces within density functional theory. We consider the energetics and electronic structure of the interface, including the role of oxygen vacancies and band offsets. In addition we consider the interface stability with respect to inter diffusion of La and Sr across the interface.
Food Safety Program in Asian Countries.
Yamaguchi, Ryuji; Hwang, Lucy Sun
By using the ILSI network in Asia, we are holding a session focused on food safety programs in several Asian areas. In view of the external environment, it is expected to impact the global food system in the near future, including the rapid increase in food demand and in public health services due to population growth, as well as the threats to biosecurity and food safety due to the rapid globalization of the food trade. Facilitating effective information sharing holds promise for the activation of the food industry. At this session, Prof. Hwang shares the current situation of Food Safety and Sanitation Regulations in Taiwan. Dr. Liu provides a talk on the role of risk assessment in food regulatory control focused on aluminum-containing food additives in China. After the JECFA evaluation of aluminum-containing food additives in 2011, each country has carried out risk assessment based on dietary intake surveys. Ms. Chan reports on the activities of a working group on Food Standards Harmonization in ASEAN. She also explains that the ILSI Southeast Asia Region has actively supported the various ASEAN Working Groups in utilizing science to harmonize food standards. Prof. Park provides current research activities in Korea focused on the effect of climate change on food safety. Climate change is generally seen as having a negative impact on food security, particularly in developing countries. We use these four presentations as a springboard to vigorous discussion on issues related to Food Safety in Asia.
New extended standard model, dark matters and relativity theory
NASA Astrophysics Data System (ADS)
Hwang, Jae-Kwang
Three-dimensional quantized space model is newly introduced as the extended standard model. Four three-dimensional quantized spaces with total 12 dimensions are used to explain the universes including ours. Electric (EC), lepton (LC) and color (CC) charges are defined to be the charges of the x1x2x3, x4x5x6 and x7x8x9 warped spaces, respectively. Then, the lepton is the xi(EC) - xj(LC) correlated state which makes 3x3 = 9 leptons and the quark is the xi(EC) - xj(LC) - xk(CC) correlated state which makes 3x3x3 = 27 quarks. The new three bastons with the xi(EC) state are proposed as the dark matters seen in the x1x2x3 space, too. The matter universe question, three generations of the leptons and quarks, dark matter and dark energy, hadronization, the big bang, quantum entanglement, quantum mechanics and general relativity are briefly discussed in terms of this new model. The details can be found in the article titled as ``journey into the universe; three-dimensional quantized spaces, elementary particles and quantum mechanics at https://www.researchgate.net/profile/J_Hwang2''.
Electronic structure of interfaces between insulating LaAlO3 and SrTiO3 perovskite oxides
NASA Astrophysics Data System (ADS)
Park, Min Sik; Rhim, S. H.; Freeman, A. J.
Since heteroepitaxial structures of perovskite oxides are potent candidates for multifunctional devices, understanding their interface properties is very important for applications, because they often show completely different properties from bulk. Recently, interfaces between the wide-band gap insulators of LaAlO3 and SrTiO3, were found to be insulating when hole-doped, and conducting when electron-doped. First-principles calculations with the highly precise full-potential linearized augmented plane wave (FLAPW) method for the stoichiometric compounds on [001] superlattices composed of perovskite unit cells of LaAlO3 and SrTiO3, show metallicity in both the hole-doped AlO2/SrO and electron-doped LaO/TiO2 interfaces, even with inclusion of geometry relaxation. Only by considering oxygen vacancies is the experimental result of insulating behavior in the hole-doped AlO2/SrO interface obtained. A. Ohtommo and H. Y. Hwang, Nature 427, 423 (2004). Wimmer, Krakauer, Weinert, Freeman, Phys.Rev.B, 24, 864 (1981)
Abundant storage protein depletion from tuber proteins using ethanol precipitation method: Suitability to proteomics study.
Lee, Hye Min; Gupta, Ravi; Kim, Sun Hyung; Wang, Yiming; Rakwal, Randeep; Agrawal, Ganesh Kumar; Kim, Sun Tae
High-abundance proteins (HAPs) hamper in-depth proteome study necessitating development of a HAPs depletion method. Here, we report a novel ethanol precipitation method (EPM) for HAPs depletion from total tuber proteins. Ethanol showed a dose-dependent effect on depletion of sporamin from sweet potato and patatin from potato tubers, respectively. The 50% ethanol was an optimal concentration. 2DE analysis of EPM-prepared sweet potato proteins also revealed enrichment of storage proteins (SPs) in ethanol supernatant (ES) resulting in detection of new low-abundance proteins in ethanol pellet (EP), compared to total fraction. The ES fraction showed even higher trypsin inhibitor activity than total proteins, further showing the efficacy of EPM in enrichment of sporamin in ES fraction. Application of this method was demonstrated for comparative proteomics of two sweet potato cultivars (Hwang-geum and Ho-bac) and purification of SP (sporamin) in its native form, as examples. Comparative proteomics identified many cultivar specific protein spots and selected spots were confidently assigned for their protein identity using MALDI-TOF-TOF analysis. Overall, the EPM is simple, reproducible, and economical for depletion of SPs and is suitable for downstream proteomics study. This study opens a door for its potential application to other tuber crops or fruits rich in carbohydrates.
The discovery of processing stages: Extension of Sternberg's method.
Anderson, John R; Zhang, Qiong; Borst, Jelmer P; Walsh, Matthew M
We introduce a method for measuring the number and durations of processing stages from the electroencephalographic signal and apply it to the study of associative recognition. Using an extension of past research that combines multivariate pattern analysis with hidden semi-Markov models, the approach identifies on a trial-by-trial basis where brief sinusoidal peaks (called bumps) are added to the ongoing electroencephalographic signal. We propose that these bumps mark the onset of critical cognitive stages in processing. The results of the analysis can be used to guide the development of detailed process models. Applied to the associative recognition task, the hidden semi-Markov models multivariate pattern analysis method indicates that the effects of associative strength and probe type are localized to a memory retrieval stage and a decision stage. This is in line with a previously developed the adaptive control of thought-rational process model, called ACT-R, of the task. As a test of the generalization of our method we also apply it to a data set on the Sternberg working memory task collected by Jacobs, Hwang, Curran, and Kahana (2006). The analysis generalizes robustly, and localizes the typical set size effect in a late comparison/decision stage. In addition to providing information about the number and durations of stages in associative recognition, our analysis sheds light on the event-related potential components implicated in the study of recognition memory. (PsycINFO Database Record
[Fraudulent publication in medical journals].
Becerril-Ángeles, Martín; García-Gómez, Francisco
Fraud can be present in some scientific medical publications; however, the magnitude of this situation is unknown. One of the associated factors for this transgression of the good practice of investigation is the need to publish and obtain recognition and benefits, regardless of the means. The deliberate fabrication and falsification of data, plagiarism and duplication of publications are some of the scientific misconducts. Many cases of fraud in publications are known, and they have reached public opinion and have been a matter of legal sanctions (the names of Woo Suk Hwang, Jon Sudbo, Joachim Blodt, Robert Slutsky, and William Summerlin reminds us a few known cases). In the last decades, national and international regulatory organisms have been created in order to intervene against this scientific misconduct. Currently, we can rely on several effective software programs, whose function is to detect plagiarism and falsification of data. The prevention of scientific misconduct through information and education of the investigators could lead to the decrease of the presence of this problem, which damages scientific credibility and put at risk the patient's safety.
[The embryonic stem cells research. Example of biotechnology progress under extra-scientific pressure].
Gámez Escalona, José Antonio
The possibility to isolate, cultivate, preserve, characterize and differentiate Human Embryonic Stem Cells (ES) discovered by James Thomson and his colleagues in 1998 was a milestone in the history of Stem Cell Research. Immediately after this discovery many speculations were made about the therapeutic possibilities of ES, motivated by ideological, political and economic aspects. The episode made clear the lack of scientific rationality and ethics when assessing realities as meaningful as those of human embryos obtained by in vitro fertilization techniques (IVF) or human eggs. Therapeutic Cloning as a promise to produce ″tailored″ Stem Cells reported by Hwang and his team in 2004, ended up being a scandal within the scientific community. The technical difficulties and ethical controversies that arose from obtaining ES were insurmountable. In 2010 only two clinical trials were reported using these cells. Those trials were abandoned in late 2011 arguing financial reasons. The discovery of Induced Pluripotent Stem Cell (iPS) in 2006 in mice and in 2007 in humans, represented the possibility of obtaining pluripotent stem cells without the need to destroy embryos. Today, the absence of clinical trials using ES, caused by financial difficulties as a result of its ineffectiveness, anticipates that the use of ES will be limited to certain experimental controls. Probably, the main contribution of Embryonic Stem Cells will be the understanding that biomedical research should follow an ethically and rationally based rigorous method that cannot be ignore.
Elastocaloric cooling materials and systems
NASA Astrophysics Data System (ADS)
Takeuchi, Ichiro
We are actively pursuing applications of thermoelastic (elastocaloric) cooling using shape memory alloys. Latent heat associated with martensitic transformation of shape memory alloys can be used to run cooling cycles with stress-inducing mechanical drives. The coefficient of performance of thermoelastic cooling materials can be as high as 11 with the directly measured DT of around 17 °C. Depending on the stress application mode, the number of cycles to fatigue can be as large as of the order of 105. Efforts to design and develop thermoelastic alloys with long fatigue life will be discussed. The current project at the University of Maryland is focused on development of building air-conditioners, and at Maryland Energy and Sensor Technologies, smaller scale commercial applications are being pursued. This work is carried out in collaboration with Jun Cui, Yiming Wu, Suxin Qian, Yunho Hwang, Jan Muehlbauer, and Reinhard Radermacher, and it is funded by the ARPA-E BEETIT program and the State of Maryland.
NBC3 expression in rabbit collecting duct: colocalization with vacuolar H+-ATPase.
Pushkin, A; Yip, K P; Clark, I; Abuladze, N; Kwon, T H; Tsuruoka, S; Schwartz, G J; Nielsen, S; Kurtz, I
We have recently cloned and characterized a unique sodium bicarbonate cotransporter, NBC3, which unlike other members of the NBC family, is ethylisopropylamiloride (EIPA) inhibitable, DIDS insensitive, and electroneutral (A. Pushkin, N. Abuladze, I. Lee, D. Newman, J. Hwang, and I. Kurtz. J. Biol. Chem. 274: 16569-16575, 1999). In the present study, a specific polyclonal antipeptide COOH-terminal antibody, NBC3-C1, was generated and used to determine the pattern of NBC3 protein expression in rabbit kidney. A major band of approximately 200 kDa was detected on immunoblots of rabbit kidney. Immunocytochemistry of rabbit kidney frozen sections revealed specific staining of the apical membrane of intercalated cells in both the cortical and outer medullary collecting ducts. The pattern of NBC3 protein expression in the collecting duct was nearly identical to the same sections stained with an antibody against the vacuolar H+-ATPase 31-kDa subunit. In addition, the NBC3-C1 antibody coimmunoprecipitated the vacuolar H+-ATPase 31-kDa subunit. Functional studies in outer medullary collecting ducts (inner stripe) showed that type A intercalated cells have an apical Na+-dependent base transporter that is EIPA inhibitable and DIDS insensitive. The data suggest that NBC3 participates in H+/base transport in the collecting duct. The close association of NBC3 and the vacuolar H+-ATPase in type A intercalated cells suggests a potential structural/functional interaction between the two transporters.
Towards secure quantum key distribution protocol for wireless LANs: a hybrid approach
NASA Astrophysics Data System (ADS)
Naik, R. Lalu; Reddy, P. Chenna
The primary goals of security such as authentication, confidentiality, integrity and non-repudiation in communication networks can be achieved with secure key distribution. Quantum mechanisms are highly secure means of distributing secret keys as they are unconditionally secure. Quantum key distribution protocols can effectively prevent various attacks in the quantum channel, while classical cryptography is efficient in authentication and verification of secret keys. By combining both quantum cryptography and classical cryptography, security of communications over networks can be leveraged. Hwang, Lee and Li exploited the merits of both cryptographic paradigms for provably secure communications to prevent replay, man-in-the-middle, and passive attacks. In this paper, we propose a new scheme with the combination of quantum cryptography and classical cryptography for 802.11i wireless LANs. Since quantum cryptography is premature in wireless networks, our work is a significant step forward toward securing communications in wireless networks. Our scheme is known as hybrid quantum key distribution protocol. Our analytical results revealed that the proposed scheme is provably secure for wireless networks.
Behavioral adjustments of African herbivores to predation risk by lions: spatiotemporal variations influence habitat use.
Valeix, M; Loveridge, A J; Chamaillé-Jammes, S; Davidson, Z; Murindagomo, F; Fritz, H; Macdonald, D W
Predators may influence their prey populations not only through direct lethal effects, but also through indirect behavioral changes. Here, we combined spatiotemporal fine-scale data from GPS radio collars on lions with habitat use information on 11 African herbivores in Hwange National Park (Zimbabwe) to test whether the risk of predation by lions influenced the distribution of herbivores in the landscape. Effects of long-term risk of predation (likelihood of lion presence calculated over four months) and short-term risk of predation (actual presence of lions in the vicinity in the preceding 24 hours) were contrasted. The long-term risk of predation by lions appeared to influence the distributions of all browsers across the landscape, but not of grazers. This result strongly suggests that browsers and grazers, which face different ecological constraints, are influenced at different spatial and temporal scales in the variation of the risk of predation by lions. The results also show that all herbivores tend to use more open habitats preferentially when lions are in their vicinity, probably an effective anti-predator behavior against such an ambush predator. Behaviorally induced effects of lions may therefore contribute significantly to structuring African herbivore communities, and hence possibly their effects on savanna ecosystems.
Influence of prey dispersion on territory and group size of African lions: a test of the resource dispersion hypothesis.
Valeix, Marion; Loveridge, Andrew J; MacDonald, David W
Empirical tests of the resource dispersion hypothesis (RDH), a theory to explain group living based on resource heterogeneity, have been complicated by the fact that resource patch dispersion and richness have proved difficult to define and measure in natural systems. Here, we studied the ecology of African lions Panthera leo in Hwange National Park, Zimbabwe, where waterholes are prey hotspots, and where dispersion of water sources and abundance of prey at these water sources are quantifiable. We combined a 10-year data set from GPS-collared lions for which information of group composition was available concurrently with data for herbivore abundance at waterholes. The distance between two neighboring waterholes was a strong determinant of lion home range size, which provides strong support for the RDH prediction that territory size increases as resource patches are more dispersed in the landscape. The mean number of herbivore herds using a waterhole, a good proxy of patch richness, determined the maximum lion group biomass an area can support. This finding suggests that patch richness sets a maximum ceiling on lion group size. This study demonstrates that landscape ecology is a major driver of ranging behavior and suggests that aspects of resource dispersion limit group sizes.
Diet quality in a wild grazer declines under the threat of an ambush predator.
Barnier, Florian; Valeix, Marion; Duncan, Patrick; Chamaillé-Jammes, Simon; Barre, Philippe; Loveridge, Andrew J; Macdonald, David W; Fritz, Hervé
Predators influence prey populations not only through predation itself, but also indirectly through prompting changes in prey behaviour. The behavioural adjustments of prey to predation risk may carry nutritional costs, but this has seldom been studied in the wild in large mammals. Here, we studied the effects of an ambush predator, the African lion (Panthera leo), on the diet quality of plains zebras (Equus quagga) in Hwange National Park, Zimbabwe. We combined information on movements of both prey and predators, using GPS data, and measurements of faecal crude protein, an index of diet quality in the prey. Zebras which had been in close proximity to lions had a lower quality diet, showing that adjustments in behaviour when lions are within short distance carry nutritional costs. The ultimate fitness cost will depend on the frequency of predator-prey encounters and on whether bottom-up or top-down forces are more important in the prey population. Our finding is the first attempt to our knowledge to assess nutritionally mediated risk effects in a large mammalian prey species under the threat of an ambush predator, and brings support to the hypothesis that the behavioural effects of predation induce important risk effects on prey populations.
Correction factors for the INER-improved free-air ionization chambers calculated with the Monte Carlo method.
Lin, Uei-Tyng; Chu, Chien-Hau
Monte Carlo method was used to simulate the correction factors for electron loss and scattered photons for two improved cylindrical free-air ionization chambers (FACs) constructed at the Institute of Nuclear Energy Research (INER, Taiwan). The method is based on weighting correction factors for mono-energetic photons with X-ray spectra. The newly obtained correction factors for the medium-energy free-air chamber were compared with the current values, which were based on a least-squares fit to experimental data published in the NBS Handbook 64 [Wyckoff, H.O., Attix, F.H., 1969. Design of free-air ionization chambers. National Bureau Standards Handbook, No. 64. US Government Printing Office, Washington, DC, pp. 1-16; Chen, W.L., Su, S.H., Su, L.L., Hwang, W.S., 1999. Improved free-air ionization chamber for the measurement of X-rays. Metrologia 36, 19-24]. The comparison results showed the agreement between the Monte Carlo method and experimental data is within 0.22%. In addition, mono-energetic correction factors for the low-energy free-air chamber were calculated. Average correction factors were then derived for measured and theoretical X-ray spectra at 30-50 kVp. Although the measured and calculated spectra differ slightly, the resulting differences in the derived correction factors are less than 0.02%.
Magnetism and multiferroicity of an isosceles triangular lattice antiferromagnet Sr3NiNb2O9
NASA Astrophysics Data System (ADS)
Lee, M.; Choi, E. S.; Ma, J.; Sinclair, R.; Dela Cruz, C. R.; Zhou, H. D.
Various experimental measurements were performed to complete the phase diagram of a weakly distorted triangular lattice system, Sr3NiNb2O9 with Ni2+ , spin-1 magnetic ions. This compound possesses an isosceles triangular lattice with two shorter bonds and one longer bond. It shows a two-step magnetic phase transition at {{T}\\text{N1}}∼ 5.1 K and {{T}\\text{N2}}∼ 5.5 K at zero magnetic field, characteristic of an easy-axis anisotropy. In the magnetization curves, a series of magnetic phase transitions was observed such as an up-up-down phase at {μ0}{{H}c1}∼ 10.5 T with 1/3 of the saturation magnetization (M sat) and an oblique phase at {μ0}{{H}c2}∼ 16 T with \\sqrt{3} /3 M sat. Intriguingly, the magnetic phase transition below T N2 is in tandem with the ferroelectricity, which demonstrates multiferroic behaviors. Moreover, the multiferroic phase persists in all magnetically ordered phases regardless of the spin structure. The comparison between the phase diagrams of Sr3NiNb2O9 and its sister compound with an equilateral triangular lattice antiferromagnet Ba3NiNb2O9 (Hwang et al 2012 Phys. Rev. Lett. 109 257205), illustrates how a small imbalance among exchange interactions change the magnetic ground states of the TLAFs.
Real-time Fluorescence Polarization Microscopy of the Moving Boundary in Cross-Gradient SDS-PAGE
NASA Astrophysics Data System (ADS)
Hwang, Jeeseong; Giulian, Gary
Real-time Fluorescence Polarization Microscopy of the Moving Boundary in Cross-Gradient SDS-PAGE Jeeseong Hwang, Jeffrey R. Krogmeier, Angela M. Bardo, Scott N. Goldie, Lori S. Goldner; Optical Technology Division, National Institute of Standards and Technology, Gaithersburg, MD 20899 Gary G. Giulian, Carl R. Merril; National Institute of Mental Health, National Institutes of Health, Bethesda, MD 20892 Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE) is a popular method to separate proteins by their apparent molecular weight. However, it is a limited technique due, in part, to its low spatial resolution. In order to improve the resolution and to enhance the detection sensitivity of proteins separated by SDS-PAGE we are studying the detergent properties at the moving boundary of precast Tris-Tricine-Acetate cross-gradient gels using fluorescent cationic and pH indicating dyes. We have developed real-time full-field fluorescence polarization microscopy to monitor the dynamic fluorescence anisotropy from the cationic tetramethylindocarbocyanine dyes localized in the "extended stack", a concentrated detergent zone. We will present quantitative results of the fluorescence anisotropy. Our system is capable of analyzing local structures of the detergent molecules in the moving boundary of SDS-PAGE and the microenvironment(s) near the boundary. We will discuss the significance of these results and their potential role in enhanced protein separation.
Anisotropic magneto-resistance of 2D holes in GaAs/Al_xGa_1-xAs heterostructure under in-plane magnetic field
NASA Astrophysics Data System (ADS)
Noh, H.; Tsui, D. C.; Shayegan, M.; Yoon, Jongsoo
We report on measurements of anisotropic in-plane magneto-resistance of the 2D hole system (2DHS) in a GaAs/AlGaAs (311)A heterostructure, which exhibits both zero-field and in-plane field induced metal-insulator transitions. For high hole densities, when the direction of B field is changed relative to the current(I), which is always kept in the high mobility direction, the resistivity with B allel I is larger at low field, while the resistivity with B ⊥ I becomes larger at high field. This behavior is consistent with recent measurements(S. J. Papadakis et al.), cond-mat/9911239. on a quantum well system. That the resistivity at high field is larger for B ⊥ I than for B allel I is also consistent with a recent theoretical argument(S. Das Sarma and E. H. Hwang, cond-mat/9909452.), though the difference is smaller than that from the theory. As the density is lowered, the resistivity with B allel I gets larger at high field, and it eventually becomes greater than that with B ⊥ I at all field ranges measured. This change in anisotropy has not been seen in previous measurements. The critical field B_c, beyond which the metallic phase becomes insulating, is also different for two different directions of B, while the change in I-V characteristics across Bc remains the same.
Single side strapping: a new approach to fine tuning the anion recognition properties of calix[4]pyrroles.
Lee, Chang-Hee; Na, Hee-Kyung; Yoon, Dae-Wi; Won, Dong-Hoon; Cho, Won-Seob; Lynch, Vincent M; Shevchuk, Sergey V; Sessler, Jonathan L
Three calix[4]pyrroles bearing m-orcinol-derived diether straps of different lengths on one side of the tetrapyrrolic core have been synthesized and characterized. Structural information for an analogous diester bridged strapped system reported previously (Yoon, D. W.; Hwang, H.; Lee, C. H. Angew. Chem., Int. Ed. Engl. 2002, 41, 1757-1759) is also provided as are bromide and chloride anion affinities for all four systems determined by Isothermal Titration Calorimetry (ITC) in acetonitrile. Although both sets of the strapped calix[4]pyrroles displayed enhanced affinities for chloride and bromide anion, differences were seen among the various receptors that support the conclusion that the anion binding ability of calixpyrrole-type systems can be effectively tuned by modifying the length and nature of the bridging straps. In the specific case of the diether systems, the largest chloride affinity was seen with the shortest strap, whereas the largest affinity for bromide anion was recorded in the case of the longest strap. On the basis of these findings, as well as supporting (1)H NMR spectroscopic studies, it is postulated that not only cavity size per se, but also the ability of the aryl portion of the strap to serve as a CH hydrogen bond donor site are important in regulating the observed anion affinities.
Observations and Simulations of Electron Dynamics Near an Active Neutral Line
NASA Technical Reports Server (NTRS)
Goldstein, M. L.; Hwang, Kyoung-Joo; Ashour-Abdalla, Maha; El-Aloui, Mostafa; Schriver, David; Richard, Robert; Zhou, Meng; Walker, Ray
Recent observations in the Earth's magnetotail have shown rapid increases in the fluxes of energetic electrons with energies up to 100's of keV associated with dipolarization fronts that propagate into the inner magnetosphere. On August 15, 2001 the four Cluster spacecraft located slightly dawnward of midnight (yGSM approx. -5.4RE) at xGSM approx. -18RE observed a series of earthward propagating dipolarization fronts [Hwang et al., 2010]. At least 6 dipolarization fronts were observed in a 20m interval. Unlike previously reported cases the fluxes of electrons up to 95keV decreased during the passage of the first three fronts over the spacecraft. The energetic electron fluxes increased during the passage of the last three fronts. We have performed a global magnetohydrodynamic simulation of this event using solar wind observations from the ACE satellite to drive the simulation. In the simulation a very complex reconnection system in the near-Earth tail at XGSM approx. -20RE launched a series of earthward propagating dipolarization fronts that are similar to those observed on Cluster. The simulation results indicate that the Cluster spacecraft were just earthward of the reconnection site. In this paper we will present a study of the dynamics of electrons associated with these events by using the large-scale kinetic simulation approach in which we launch a large number of electrons into the electric and magnetic fields from this simulation.
Effect of directional distribution on non-linear energy transfer in wind wave spectrum
NASA Astrophysics Data System (ADS)
Lavrenov, I.; Krogstad, H.
Different directional distribution is investigated from the point of view a non-linear energy transfer in wind wave spectrum. In order to produce a numerical simulation of the non-linear interaction in wind wave spectrum a method of numerical integration of the highest accuracy is used. It is shown that the value of non-linear energy transfer is very sensitive to details of frequency-angular approximation of wave spectrum. The non-linear energy transfer is non-zero in wide frequency - angular range, depending on spectrum angular distribution. The calculation results reveal the presence of non-linear energy transfer to spectral components, which propagation is opposite to wind direction for a wide spectrum angular distribution. It should be noted that neither the discrete interaction approximation (DIA) used in the WAM model (Komen et al., 1994), no diffusive approximation of the non-linear transfer (Pushkarev and Zakharov, 1999) are able not to produce this effect. Numerical results show that the bi-model angular distribution, obtained by Hwang et al. (2000) in field experiments, can be generated by the non-linear energy transfer, sending energy in side direction. Present study has been supported by the INTAS-99-666, INTAS-01-25, INTAS-01-234, INTAS-01-2156, RFBR- 01- 05-64846 Grants.
Connecting historical disk interactions with current planetary system architectures
NASA Astrophysics Data System (ADS)
Ellinger, Emily; Steffen, Jason H.
Recent analyses of Kepler's multiplanet systems show several statistically significant peaks in the distribution of period ratios (Steffen & Hwang arXiv:1409.3320). One prominent peak is near a period ratio of 2.2. Usually planets that migrate in a gas disk become trapped at period ratios of 2:1, 3:2, etc. Thus, standard disk migration would not predict a large number of planets near 2.2. A paper by Baruteau, C. & Papaloizou, J. (2013, ApJ, 778, 7-21) may have identified an explanation to the unexpected peak. Planets in a gas disk that open a common gap often bypassed the 2:1 resonance and stopped their migration at smaller period ratios. However, planets that did not open a common gap often stopped their migration wide of the 2:1 resonance due to interactions with the wakes left by the planets. Using FARGO3D to model planet/disk interactions I hope to identify the system parameters that are needed to produce the observed period ratios. This information will give important insights into the dynamical evolution of planetary systems. We present the results of our simulations.
Flow noise predictions of a submerged cylinder under turbulent boundary layer excitations
NASA Astrophysics Data System (ADS)
Wu, Kuangcheng; Vlahopoulos, Nickolas
The unsteady fluctuated pressure underneath turbulent boundary layers (TBL) is one of major noise sources in moving vehicles. Recently, discretized TBL forcing functions have been applied to planar structures in air [Y. F. Hwang and S. A. Hambric, Noise-Con, 2000; M. Allen and N. Vlahopoulos, Computers and Structures, 2000; M. Allen and N. Vlahopoulos, Finite Elements in Analysis and Design, 2001; M. Allen, R. Sbragio, and N. Vlahopoulos, AIAA J. 2001]. This paper discusses prediction of the flow-induced radiated noise and surface responses of a submerged hemisphere-capped cylindrical shell (L/D=11). The FEM/IFEM (infinite finite element method) approach is used to calculate structural acoustic transfer functions and to accurately account for the fluid loading effects. The effect on TBL due to the curvature of a cylinder is captured by utilizing the potential flow-boundary layer theory to determine key boundary layer parameters. Predictions of the surface intensity and far field responses are developed through stochastic analysis due to the natural of the TBL excitations. A MATLAB script is generated to determine the power spectral density of the responses. [Work supported by ONR Code 334.
Behavioural inventory of the giraffe (Giraffa camelopardalis)
Background Numerous factors like continuous habitat reduction or fragmentation for free-ranging giraffes (Giraffa camelopardalis) as well as e.g. suboptimal housing conditions for animals in captivity might lead to behavioural alterations as part of the overall adaptation process to the changing living conditions. In order to facilitate current and future studies on giraffe behaviour, a comprehensive ethogram was compiled based on existing literature, as well as observations on giraffes in the wild (Hwange National Park, Zimbabwe; Entabeni Game Reserve, South Africa), and in captivity (National Zoological Gardens of South Africa, Pretoria). Findings The resulting ethogram lists 65 different behavioural patterns, which were described and grouped into seven categories: General activities, Abnormal repetitive behaviours, General interactions, Bull-Cow behaviour, Bull-Bull behaviour, Cow-Bull behaviour, Maternal behaviours, and Interactions by calves. The behaviours were further described regarding a presumed purpose, particularly with respect to social interactions and sexual behaviour. Contradictory descriptions from previous studies were considered and discussed in comparison with our own observations. Conclusions This ethogram provides a basis for current and future studies by suggesting a terminology which can be used for harmonizing behavioural observations, thus helping to facilitate comparability of future results. Subsequently, a better understanding of the behavioural ecology of giraffes in the wild as well as in captivity could aid future conservation efforts. PMID:23173954
Enhancing of a Password-Based Authentication Scheme Using Smart Cards
NASA Astrophysics Data System (ADS)
Lee, Youngsook; Won, Dongho
A password based remote user authentication scheme is a two-party protocol whereby an authentication server in a distributed system confirms the identity of a remote individual logging on to the server over an untrusted, open network. This paper discusses the security of Chen et al.'s remote user authentication scheme making use of smart cards. They have recently presented an improved version of Lin, Shen, and Hwang's scheme. But, unlike their claims, in Chen et al.'s scheme, if an attacker gains access to some user's smart card and extracts the information stored in the smart card, he/she can easily find out the user's password. We show this by mounting a dictionary attack on the scheme. In addition, Chen et al.'s scheme does not support its main security goal of authenticating between a remote individual and the server. This is shown via a sever impersonation attack on the scheme. Motivated by these security flaws, we propose a more secure remote user authentication scheme that achieves both two-factor security and mutual authentication.
Traditional Chinese Medicine and herbal hepatotoxicity: a tabular compilation of reported cases.
Teschke, Rolf; Zhang, Li; Long, Hongzhu; Schwarzenboeck, Alexander; Schmidt-Taenzer, Wolfgang; Genthner, Alexander; Wolff, Albrecht; Frenzel, Christian; Schulze, Johannes; Eickhoff, Axel
Traditional Chinese Medicine (TCM) with its focus on herbal use became popular worldwide. Treatment was perceived as safe, with neglect of rare adverse reactions including liver injury. To compile worldwide cases of liver injury by herbal TCM, we undertook a selective literature search in the PubMed database and searched for the items Traditional Chinese Medicine, TCM, Traditional Asian Medicine, and Traditional Oriental Medicine, also combined with the terms herbal hepatotoxicity or herb induced liver injury. The search focused primarily on English-language case reports, case series, and clinical reviews. We identified reported hepatotoxicity cases in 77 relevant publications with 57 different herbs and herbal mixtures of TCM, which were further analyzed for causality by the Council for International Organizations of Medical Sciences (CIOMS) scale, positive reexposure test results, or both. Causality was established for 28/57 different herbs or herbal mixtures, Bai Xian Pi, Bo He, Ci Wu Jia, Chuan Lian Zi, Da Huang, Gan Cao, Ge Gen, Ho Shou Wu, Huang Qin, Hwang Geun Cho, Ji Gu Cao, Ji Xue Cao, Jin Bu Huan, Jue Ming Zi, Jiguja, Kudzu, Ling Yang Qing Fei Keli, Lu Cha, Rhen Shen, Ma Huang, Shou Wu Pian, Shan Chi, Shen Min, Syo Saiko To, Xiao Chai Hu Tang, Yin Chen Hao, Zexie, and Zhen Chu Cao. In conclusion, this compilation of liver injury cases establishes causality for 28/57 different TCM herbs and herbal mixtures, aiding diagnosis for physicians who care for patients with liver disease possibly related to herbal TCM.
Comment on ``Study of dielectric relaxations of anhydrous trehalose and maltose glasses'' [J. Chem. Phys. 134, 014508 (2011)
NASA Astrophysics Data System (ADS)
Kaminski, K.; Wlodarczyk, P.; Paluch, M.
Very recently Kwon et al. [H.-J. Kwon, J.-A. Seo, H. K. Kim, and Y. H. Hwang, J. Chem. Phys. 134, 014508 (2011)] published an article on the study of dielectric relaxation in trehalose and maltose glasses. They carried out broadband dielectric measurements at very wide range of temperatures covering supercooled liquid as well as glassy state of both saccharides. It is worth to mention that authors have also applied a new method for obtaining anhydrous glasses of trehalose and maltose that enables avoiding their caramelization. Four relaxation processes were identified in dielectric spectra of both saccharides. The slower one was identified as structural relaxation process the next one, not observed by the others, was assigned as Johari-Goldstein (JG) β-relaxation, while the last two secondary modes were of the same nature as found by Kaminski et al. [K. Kaminski, E. Kaminska, P. Wlodarczyk, S. Pawlus, D. Kimla, A. Kasprzycka, M. Paluch, J. Ziolo, W. Szeja, and K. L. Ngai, J. Phys. Chem. B 112, 12816 (2008)]. In this comment we show that the authors mistakenly assigned the slowest relaxation process as structural mode of disaccharides. We have proven that this relaxation process is an effect of formation of thin layer of air or water between plate of capacitor and sample. The same effect can be observed if plates of capacitor are oxidized. Thus, we concluded that their slowest mode is connected to the dc conduction process while their β JG process is primary relaxation of trehalose and maltose.
Adaptive memory: the survival scenario enhances item-specific processing relative to a moving scenario.
Burns, Daniel J; Hart, Joshua; Griffith, Samantha E; Burns, Amy D
Nairne, Thompson, and Pandeirada (2007) found that retention of words rated for their relevance to survival is superior to that of words encoded under numerous other deep processing conditions. They suggested that our memory systems might have evolved to confer an advantage for survival-relevant information. Burns, Burns, and Hwang (2011) suggested a two-process explanation of the proximate mechanisms responsible for the survival advantage. Whereas most control tasks encourage only one type of processing, the survival task encourages both item-specific and relational processing. They found that when control tasks encouraged both types of processing, the survival processing advantage was eliminated. However, none of their control conditions included non-survival scenarios (e.g., moving, vacation, etc.), so it is not clear how this two-process explanation would explain the survival advantage when scenarios are used as control conditions. The present experiments replicated the finding that the survival scenario improves recall relative to a moving scenario in both a between-lists and within-list design and also provided evidence that this difference was accompanied by an item-specific processing difference, not a difference in relational processing. The implications of these results for several existing accounts of the survival processing effect are discussed.
Improved estimation of the noncentrality parameter distribution from a large number of t-statistics, with applications to false discovery rate estimation in microarray data analysis.
Qu, Long; Nettleton, Dan; Dekkers, Jack C M
Given a large number of t-statistics, we consider the problem of approximating the distribution of noncentrality parameters (NCPs) by a continuous density. This problem is closely related to the control of false discovery rates (FDR) in massive hypothesis testing applications, e.g., microarray gene expression analysis. Our methodology is similar to, but improves upon, the existing approach by Ruppert, Nettleton, and Hwang (2007, Biometrics, 63, 483-495). We provide parametric, nonparametric, and semiparametric estimators for the distribution of NCPs, as well as estimates of the FDR and local FDR. In the parametric situation, we assume that the NCPs follow a distribution that leads to an analytically available marginal distribution for the test statistics. In the nonparametric situation, we use convex combinations of basis density functions to estimate the density of the NCPs. A sequential quadratic programming procedure is developed to maximize the penalized likelihood. The smoothing parameter is selected with the approximate network information criterion. A semiparametric estimator is also developed to combine both parametric and nonparametric fits. Simulations show that, under a variety of situations, our density estimates are closer to the underlying truth and our FDR estimates are improved compared with alternative methods. Data-based simulations and the analyses of two microarray datasets are used to evaluate the performance in realistic situations.
Documentation of some Cultural Heritage Emergencies in Syria In August 2010 by Spherical Photrammetry
NASA Astrophysics Data System (ADS)
Fangi, G.
Syria is a country of many civilizations, Marie, Aramaic, Phoenician, Roman, Byzantine, Islamic, Ottoman civilizations. Unfortunally the recent war is the reason for many cultural heritage items to be destroyed, beyond the thausand civilian people killed. In 2010, just before the war, the A. made a touristic trip together with Crua (Recreational Club of the Ancona University). It was the occasion to make some fast documentation of some Syrian CH monuments. Mostly of the images were taken by the A. not to make a survey, but as a photographic report, as fast and complete as possible. For a regular survey project, the tripod, the spherical head should be used for the takings and the 3x3 Cipa rules should be followed, that occurred only in the three main projects, say the survey of the citadel walls in Aleppo, the survey of the Umayyads Mosque in Damascus, and the survey of the minaret of the Umayyads Mosque in Aleppo. All the other documentation surveys have been carried out with hand-held camera taking the dimension of the model from Google earth high resolution, when available. But, apart the regular surveys, due to the explosion of the unexpected war, the photographs taken in such a touristic way, have been used to try to get some usable plottings an restitutions and it worked successfully mostly of the times. These surveys could be useful in case of reconstruction and in case of lack of suitable alternative metric documentation. Because of the continuing threats, all six Syrian World Heritage properties were inscribed on the List of World Heritage in Danger, at the 37th session of the World Heritage Committee, held in Cambodia last June: Ancient City of Aleppo, Ancient City of Bosra, Ancient City of Damascus, Ancient Villages of Northern Syria, Krak des Chevaliers and Qal'at Salah El-Din ans finally the Site of Palmyra. See the following links: https://www.youtube.com/watch?feature=player_embedded&v=kr.a3e0DL5sA and https
Photoemission and magnetic circular dichroism studies of magnetic semiconductors
NASA Astrophysics Data System (ADS)
Fujimori, Atsushi
Recently, a series of novel ferromagnetic semiconductors have been synthesized using MBE and related techniques and have attracted much attention because of unknown mechanisms of carrier-induced ferromagnetism and potential applications as "spin electronics" devices. Some new materials show ferromagnetism even well above room temperature. Photoemission spectroscopy has been used to study the d orbitals of the dilute transition-metal atoms, mostly Mn, and their hybridization with the host band states [1]. Soft x-ray absorption spectroscopy (XAS) and magnetic circular dichroism (MCD) at the transition-metal 2p-3d absorption edges are useful techniques to study the valence and spin states of the transition-metal atoms. Furthermore, since MCD has different sensitivities to the ferromagnetic and paramagnetic components at different temperatures and magnetic fileds, if the sample is a mixture of ferromagnetic and non-ferromagnetic transition- metal atoms, it can be used to separate the two components and to study their electronic structures. In this talk, results are presented for the prototypical diluted ferromagnetic semiconductor Ga1-xMnxAs [2] and the room-temperature ferromagnets Zn1-xCoxO and Ti1-xCoxO2.I acknowledge collaboration with Y. Ishida, J.-I. Hwang, M. Kobayashi, Y. Takeda, Y. Saitoh, J. Okamoto, T. Okane, Y. Muramatsu, K. Mamiya, T. Koide, A. Tanaka, M. Tanaka, Hayashi, S. Ohya, T. Kondo, H. Munekata, H. Saeki, H. Tabata, T. Kawai, Y. Matsumoto, H. Koinuma, T. Fukumura and M. Kawasaki. This work was supported by a Grant-in-Aid for Scientific Research in Priority Area "Semiconductor nano-spintronics" (14076209) from MEXT, Japan.1. J. Okabayashi et al., Phys. Rev. B 64, 125304 (2001).2. A. Fujimori et al., J. Electron Spectrosc. Relat. Phenom., in press.
First Attempt of Applying Factor Analysis in Moving Base Gravimetry
NASA Astrophysics Data System (ADS)
Li, X.; Roman, D. R.
For gravimetric observation systems on mobile platforms (land/sea/airborne), the Low Signal to Noise Ratio (SNR) issue is the main barrier to achieving an accurate, high resolution gravity signal. Normally, low-pass filters (Childers et al 1999, Forsberg et al 2000, Kwon and Jekeli 2000, Hwang et al 2006) are applied to smooth or remove the high frequency "noise" - even though some of the high frequency component is not necessarily noise. This is especially true for aerogravity surveys such as those from the Gravity for the Redefinition of the American Vertical Datum (GRAV-D) project. These gravity survey flights have a spatial resolution of 10 km between tracks but higher resolution along track. The along track resolution is improved due to the lower flight height (6.1 km), equipment sensitivity, and improved modeling of potential errors. Additionally, these surveys suffer from a loss of signal power due to the increased flight elevation. Hence, application of a low-pass filter removes possible signal sensed in the along-track direction that might otherwise prove useful for various geophysical and geodetic applications. Some cutting-edge developments in Wavelets and Artificial Neural Networks had been successfully applied for obtaining improved results (Li 2008 and 2011, Liang and Liu 2013). However, a clearer and fundamental understanding of the error characteristics will further improve the quality of the gravity estimates out of these gravimetric systems. Here, instead of using any predefined basis function or any a priori model, the idea of Factor Analysis is first employed to try to extract the underlying factors of the noises in the systems. Real data sets collected by both land vehicle and aircraft will be processed as the examples.
Specific and Nonspecific Interactions in Ultraweak Protein–Protein Associations Revealed by Solvent Paramagnetic Relaxation Enhancements
Weak and transient protein–protein interactions underlie numerous biological processes. However, the location of the interaction sites of the specific complexes and the effect of transient, nonspecific protein–protein interactions often remain elusive. We have investigated the weak self-association of human growth hormone (hGH, KD = 0.90 ± 0.03 mM) at neutral pH by the paramagnetic relaxation enhancement (PRE) of the amide protons induced by the soluble paramagnetic relaxation agent, gadodiamide (Gd(DTPA-BMA)). Primarily, it was found that the PREs are in agreement with the general Hwang-Freed model for relaxation by translational diffusion (J. Chem. Phys.1975, 63, 4017–4025), only if crowding effects on the diffusion in the protein solution are taken into account. Second, by measuring the PREs of the amide protons at increasing hGH concentrations and a constant concentration of the relaxation agent, it is shown that a distinction can be made between residues that are affected only by transient, nonspecific protein–protein interactions and residues that are involved in specific protein–protein associations. Thus, the PREs of the former residues increase linearly with the hGH concentration in the entire concentration range because of a reduction of the diffusion caused by the transient, nonspecific protein–protein interactions, while the PREs of the latter residues increase only at the lower hGH concentrations but decrease at the higher concentrations because of specific protein–protein associations that impede the access of gadodiamide to the residues of the interaction surface. Finally, it is found that the ultraweak aggregation of hGH involves several interaction sites that are located in patches covering a large part of the protein surface. PMID:24969589
A Comparison of Particle and Organic Carbon Fluxes to the Deep Canada Basin Between 2004-2005 and 2007-2008
NASA Astrophysics Data System (ADS)
Eglinton, T. I.; Hwang, J.; Manganini, S. J.; Griffith, D.; Krishfield, R. A.; Honjo, S.
Two of the most blatant impacts of climate change in the Arctic are destabilization of permafrost soils, and a reduction in sea-ice cover, altering carbon cycling both on land and in the ocean. In particular, higher terrestrial carbon fluxes to the ocean, and both enhanced and an offshore extension of marine productivity, are anticipated. However, the fate of this carbon (i.e., remineralization versus burial) in the Arctic Ocean, as well as the extent to which the deep basin waters and underlying sediments will sequester carbon in the face of rapidly changing sea-ice, hydrographic and biogeochemical conditions, remain unknown. Answers to these questions are crucial to our understanding of whether the Arctic will serve as a net carbon dioxide source or sink to the atmosphere, and how pelagic ecosystems will respond to these perturbations. In this study, we compare the flux of particulate carbon and associated elements to the deep Arctic Ocean from a bottom-tethered sediment trap deployed at 3000m in the southwest Canada Basin during 2004-2005 and 2007-2008. Particle fluxes and compositions are compared in the context of different seasonal sea-ice and hydrographic conditions between these deployment periods. Overall particle fluxes during the 2004-5 deployment were extremely low, and mass flux variations were temporally decoupled from the cycle of primary productivity in overlying surface waters. Moreover, geochemical analyses showed that the sinking particulate matter was characterized by aged organic carbon and abundant lithogenic material, which together suggest that the majority of the particulate organic carbon entering the deep Canada Basin was supplied from the surrounding margins (Hwang et al. 2008, Geophys. Res. Lett. 35, L11607). These data will be compared with particle fluxes during the 2007-2008 year when summer sea ice was less extensive.
High performance communication by people with paralysis using an intracortical brain-computer interface
Pandarinath, Chethan; Nuyujukian, Paul; Blabe, Christine H; Sorice, Brittany L; Saab, Jad; Willett, Francis R; Hochberg, Leigh R
Brain-computer interfaces (BCIs) have the potential to restore communication for people with tetraplegia and anarthria by translating neural activity into control signals for assistive communication devices. While previous pre-clinical and clinical studies have demonstrated promising proofs-of-concept (Serruya et al., 2002; Simeral et al., 2011; Bacher et al., 2015; Nuyujukian et al., 2015; Aflalo et al., 2015; Gilja et al., 2015; Jarosiewicz et al., 2015; Wolpaw et al., 1998; Hwang et al., 2012; Spüler et al., 2012; Leuthardt et al., 2004; Taylor et al., 2002; Schalk et al., 2008; Moran, 2010; Brunner et al., 2011; Wang et al., 2013; Townsend and Platsko, 2016; Vansteensel et al., 2016; Nuyujukian et al., 2016; Carmena et al., 2003; Musallam et al., 2004; Santhanam et al., 2006; Hochberg et al., 2006; Ganguly et al., 2011; O'Doherty et al., 2011; Gilja et al., 2012), the performance of human clinical BCI systems is not yet high enough to support widespread adoption by people with physical limitations of speech. Here we report a high-performance intracortical BCI (iBCI) for communication, which was tested by three clinical trial participants with paralysis. The system leveraged advances in decoder design developed in prior pre-clinical and clinical studies (Gilja et al., 2015; Kao et al., 2016; Gilja et al., 2012). For all three participants, performance exceeded previous iBCIs (Bacher et al., 2015; Jarosiewicz et al., 2015) as measured by typing rate (by a factor of 1.4–4.2) and information throughput (by a factor of 2.2–4.0). This high level of performance demonstrates the potential utility of iBCIs as powerful assistive communication devices for people with limited motor function. Clinical Trial No: NCT00912041 DOI: http://dx.doi.org/10.7554/eLife.18554.001 PMID:28220753
Genetic Modification in Human Pluripotent Stem Cells by Homologous Recombination and CRISPR/Cas9 System.
Xue, Haipeng; Wu, Jianbo; Li, Shenglan; Rao, Mahendra S; Liu, Ying
Genetic modification is an indispensable tool to study gene function in normal development and disease. The recent breakthrough of creating human induced pluripotent stem cells (iPSCs) by defined factors (Takahashi et al., Cell 131:861-872, 2007) provides a renewable source of patient autologous cells that not only retain identical genetic information but also give rise to many cell types of the body including neurons and glia. Meanwhile, the rapid advancement of genome modification tools such as gene targeting by homologous recombination (Capecchi, Nat Rev Genet 6:507-512, 2005) and genome editing tools such as CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)/Cas (CRISPR-associated) system, TALENs (Transcription activator-like effector nucleases), and ZFNs (Zinc finger nucleases) (Wang et al., Cell 153:910-918, 2013; Mali et al., Science 339:823-826, 2013; Hwang et al., Nat Biotechnol 31:227-229, 2013; Friedland et al., Nat Methods 10(8):741-743, 2013; DiCarlo et al., Nucleic Acids Res 41:4336-4343, 2013; Cong et al., Science 339:819-823, 2013) has greatly accelerated the development of human genome manipulation at the molecular level. This chapter describes the protocols for making neural lineage reporter lines using homologous recombination and the CRISPR/Cas system-mediated genome editing, including construction of targeting vectors, guide RNAs, transfection into hPSCs, and selection and verification of successfully targeted clones. This method can be applied to various needs of hPSC genetic engineering at high efficiency and high reliability.
Scientific overview: CSCI-CITAC Annual General Meeting and Young Investigator's Forum 2013.
Antoun, Ghadi; Keow, Jonathan; Ram, Véronique D; Thornton, Christina; Wang, Xin; Yoon, Ju-Yoon
The 2013 joint Canadian Society of Clinician Investigators (CSCI)-Clinical Investigator Trainee Association of Canada/Association des cliniciens-chercheurs en formation du Canada (CITAC/ACCFC) annual general meeting(AGM) was held in Ottawa, September 2013. The symposium focused on "Applications of the 'omics' to Clinical Practice", with presentations from Drs. William T. Gibson (University of British Columbia), Julie Ho (University of Manitoba) and David Hwang (University of Toronto), discussing topics of genome, proteome and the microbiome, respectively. Other highlights from the 2013 AGM include presentations by Dr. Salim Yusuf (McMaster University, 2013 CSCI-RCPSC Henry Friesen Award winner), Dr. Gary Lewis (University of Toronto, 2013 CSCI Distinguished Scientist Award winner) and Dr. Michael Taylor (University of Toronto, 2013 Joe Doupe Award winner). The CSCI/CITAC/Friends of CIHR Joint Symposium consisted of presentations from Drs. John Bell (University of Ottawa), Dan Drucker (University of Toronto) and Heather J. Dean (University of Manitoba). Finally, the meeting ended with the presentation "The Power of an Idea to Bring Ideas to Power" by Dr. Harvey V. Fineberg (President, U.S. Institute of Medicine), the winner of the 2013 Henry Friesen International Prize. Also presented at the conference was research by clinician investigator (CI) trainees from across Canada; ie., those enrolled in MD/MSc, MD/PhD or Clinician Investigator Program(CIP) programs. Canadian trainees' research extended beyond the pillar of biomedical research, covering the spectrum between basic and clinical research, with a focus on the causes of significant morbidity and mortality for Canadians, including cancers, infectious diseases and other maladies. It is this research that we have summarized in this review.
African elephants adjust speed in response to surface-water constraint on foraging during the dry-season.
Chamaillé-Jammes, Simon; Mtare, Godfrey; Makuwe, Edwin; Fritz, Hervé
Most organisms need to acquire various resources to survive and reproduce. Individuals should adjust their behavior to make optimal use of the landscape and limit the costs of trade-offs emerging from the use of these resources. Here we study how African elephants Loxodonta africana travel to foraging places between regular visits to waterholes. Elephant herds were tracked using GPS collars during two consecutive dry seasons in Hwange National Park, Zimbabwe. We segmented each individual movement track at each visit to water to define foraging trips, and then used trip-level statistics to build an understanding of movement strategies. Travel speed within these individually-consistent movement bouts was also analyzed to understand if speed was better linked to distance to water or progression in the trip over time. We found that elephants went further from water when drinking less often, which could result from a trade-off between drinking and foraging in less depleted, far from water, places. Speed increased towards the beginning and the end of the trips, and was also greater than observed during the wet season, suggesting that elephants were trying to save time. Numerous short trips traveled at greater speed, particularly when commuting to a different waterhole, was tentatively explained by the inability to drink at specific waterholes due to intra-specific interference. Unexpectedly elephants did not always minimize travel time by drinking at the closest waterhole, but the extra distance traveled remained never more than a few kilometers. Our results show how individuals may adjust movement behavior to deal with resource trade-offs at the landscape scale. We also highlight how behavioral context, here progression in the trip, may be more important than spatial context, here distance to water, in explaining animal movement patterns.
Acylcarnitines: potential implications for skeletal muscle insulin resistance
Aguer, Céline; McCoin, Colin S.; Knotts, Trina A.; Thrush, A. Brianne; Ono-Moore, Kikumi; McPherson, Ruth; Dent, Robert; Hwang, Daniel H.; Adams, Sean H.; Harper, Mary-Ellen
Insulin resistance may be linked to incomplete fatty acid β-oxidation and the subsequent increase in acylcarnitine species in different tissues including skeletal muscle. It is not known if acylcarnitines participate in muscle insulin resistance or simply reflect dysregulated metabolism. The aims of this study were to determine whether acylcarnitines can elicit muscle insulin resistance and to better understand the link between incomplete muscle fatty acid β-oxidation, oxidative stress, inflammation, and insulin-resistance development. Differentiated C2C12, primary mouse, and human myotubes were treated with acylcarnitines (C4:0, C14:0, C16:0) or with palmitate with or without carnitine acyltransferase inhibition by mildronate. Treatment with C4:0, C14:0, and C16:0 acylcarnitines resulted in 20–30% decrease in insulin response at the level of Akt phosphorylation and/or glucose uptake. Mildronate reversed palmitate-induced insulin resistance concomitant with an ∼25% decrease in short-chain acylcarnitine and acetylcarnitine secretion. Although proinflammatory cytokines were not affected under these conditions, oxidative stress was increased by 2–3 times by short- or long-chain acylcarnitines. Acylcarnitine-induced oxidative stress and insulin resistance were reversed by treatment with antioxidants. Results are consistent with the conclusion that incomplete muscle fatty acid β-oxidation causes acylcarnitine accumulation and associated oxidative stress, raising the possibility that these metabolites play a role in muscle insulin resistance.—Aguer, C., McCoin, C. S., Knotts, T. A., Thrush, A. B., Ono-Moore, K., McPherson, R., Dent, R., Hwang, D. H., Adams, S. H., Harper, M.-E. Acylcarnitines: potential implications for skeletal muscle insulin resistance. PMID:25342132
Key Residues of Outer Membrane Protein OprI Involved in Hexamer Formation and Bacterial Susceptibility to Cationic Antimicrobial Peptides
Chang, Ting-Wei; Wang, Chiu-Feng; Huang, Hsin-Jye; Wang, Iren; Hsu, Shang-Te Danny
Antimicrobial peptides (AMPs) are important components of the host innate defense mechanism against invading pathogens. Our previous studies have shown that the outer membrane protein, OprI from Pseudomonas aeruginosa or its homologue, plays a vital role in the susceptibility of Gram-negative bacteria to cationic α-helical AMPs (Y. M. Lin, S. J. Wu, T. W. Chang, C. F. Wang, C. S. Suen, M. J. Hwang, M. D. Chang, Y. T. Chen, Y. D. Liao, J Biol Chem 285:8985–8994, 2010, http://dx.doi.org/10.1074/jbc.M109.078725; T. W. Chang, Y. M. Lin, C. F. Wang, Y. D. Liao, J Biol Chem 287:418–428, 2012, http://dx.doi.org/10.1074/jbc.M111.290361). Here, we obtained two forms of recombinant OprI: rOprI-F, a hexamer composed of three disulfide-bridged dimers, was active in AMP binding, while rOprI-R, a trimer, was not. All the subunits predominantly consisted of α-helices and exhibited rigid structures with a melting point centered around 76°C. Interestingly, OprI tagged with Escherichia coli signal peptide was expressed in a hexamer, which was anchored on the surface of E. coli, possibly through lipid acids added at the N terminus of OprI and involved in the binding and susceptibility to AMP as native P. aeruginosa OprI. Deletion and mutation studies showed that Cys1 and Asp27 played a key role in hexamer formation and AMP binding, respectively. The increase of OprI hydrophobicity upon AMP binding revealed that it undergoes conformational changes for membrane fusion. Our results showed that OprI on bacterial surfaces is responsible for the recruitment and susceptibility to amphipathic α-helical AMPs and may be used to screen antimicrobials. PMID:26248382
Mechanisms of herb-induced nephrotoxicity.
Allard, T; Wenner, T; Greten, H J; Efferth, T
Herbal therapies gained much popularity among the general public, but compared to therapies approved by official authorities, toxicological studies are frequently not available for them. Hence, there may be inherent risks and the kidneys may be especially vulnerable to toxic effects. Herbs may induce nephrotoxicity by induction of apoptosis. High oxalate contents in Star fruit (Averrhoa carambola L.) may induce acute nephropathy. Triptolide from Thunder God Vine (Triperygium wilfordii Hook) is a diterpenoid epoxide with induces reactive oxygen species and nephrotubular apoptosis. Cranberry juice is discussed as promoter of kidney stone formation (nephrolithiasis). Abuse of guaifenesin from Roughbark (Guaicum officinale L.) increases stone formation. Aristolochia acids from Aristolochia fangchi Y.C.Wu ex L.D. Chow & S.M. Hwang causes the well-known aristolochic acid nephropathy and carcinogenesis by DNA adduct formation. Carboxyatractyloside from Impila (Callilepsis laureola DC.) inhibits mitochondrial ATP synthesis. Acute allergic interstitial nephritis was diagnosed after intake of Peruvian Cat's claw (Uncaria tomentosa Willd. DC.). Whether or not Willow Bark (Salix alba L.) induces analgesic nephropathwy is a matter of discussion. Other herbal therapies are considered to affect the rennin-angiotensisn-aldosterone (RAA) system Ephedra sinica Stapf with its ingredient ephedrine. Devil's Claw (Harpagophytum procumbens DC. Ex Meisn.) and licorice (Glycyrrhiza glabra L.) may inhibit major renal transport processes needed for filtration, secretion, and absorption. Strategies to minimize nephrotoxicity include (1) quality control and standardization of herbal products, (2) research on the molecular modes of action to better understand pathophysiological mechanisms of herbal products as well as (3) clinical trials to demonstrate efficacy and safety.
Technical and Physical Activities of Small-Sided Games in Young Korean Soccer Players.
Joo, Chang H; Hwang-Bo, Kwan; Jee, Haemi
Joo, CH, Hwang-Bo, K, and Jee, H. Technical and physical activities of small-sided games in young Korean soccer players. J Strength Cond Res 30(8): 2164-2173, 2016-The aim of this study was to examine the technical aspects and physical demands during small-sided games (SSGs) with different sized pitches in young Korean soccer players. Participants were randomly selected during a nationally held youth competition. Three different game formats were used: SSG8 (8 vs. 8 played on a small-sized field [68 × 47 m]), RSG8 (8 vs. 8 played on a regular-sized field [75 × 47 m]), and RSG11 (11 vs. 11 played on a regular-sized field). Eleven technical (ball touches, passes, and shots) and 6 physical demand variables (exercise frequency by intensity) were observed and analyzed. Same variables were also analyzed for the goalkeepers. As a result, SSG8 and RSG8 showed significantly greater numbers of technical plays in 5 and 4 variables in comparison to RSG11, respectively. In addition, although the exercise intensities increased slightly in both SSG formats, the amount was within the similar range as previous reports. In conclusion, the SSGs with reduced number of players may be referred in young players to effectively train them in technical aspects of the game by allowing greater ball exposure time without excessive physical demands. Various confounding factors such as pitch dimension should be carefully considered for training specific technical and physical variables in young Korean players.
Observation of magnetopause fluctuations during a Cluster-THEMIS conjunction
NASA Astrophysics Data System (ADS)
Hwang, Kyoung-Joo; Goldstein, Mevlyn
On April 27, 2007, THEMIS observed quasi-periodic magnetopause fluctuations for a prolonged time period (9 hrs) as they skimmed the dusk-side magnetopause, while Cluster detected 1.5-hour-long boundary undulations as they traversed the morning-side magnetopause. The com-parison between Cluster and THEMIS with ACE data implies that: 1) Similar periodicity and patterns of its variability between Cluster and THEMIS observations, with a certain time in-terval longer than is expected from the upstream magnetosheath travel time between THEMIS and Cluster locations, indicate that the dusk-side surface waves have been excited at the nearly subsolar region; 2) The complicated inner-LLBL fluctuations observed by THEMIS have been resulted from the development and modulation of the waves according to the local environment during convection along the LLBL, while Cluster observed the magnetopause fluctuations that appear to be more explicitly controlled by SW variations in the morning sector; 3) The intensity of KHW, often well characterized by Bm power spectra reflect the effects of IMF conditions, exhibiting a correlation with SW temperature and IMF clock angle, i.e., a more solid power law when IMF points due north or south rather than due dawn or dusk; 4) Steeper wavefront at the anti-sunward/sunward edge of KHW during southward/northward IMF support more rapid and turbulent evolution of KHW under southward IMF conditions [Hwang et al., 2010; Kuznetsova et al., 2008], and the steepening effects of the curvature forces of the magnetosheath flux tubes during northward IMF [Chen et al., 1997].
High performance communication by people with paralysis using an intracortical brain-computer interface.
Pandarinath, Chethan; Nuyujukian, Paul; Blabe, Christine H; Sorice, Brittany L; Saab, Jad; Willett, Francis R; Hochberg, Leigh R; Shenoy, Krishna V; Henderson, Jaimie M
Brain-computer interfaces (BCIs) have the potential to restore communication for people with tetraplegia and anarthria by translating neural activity into control signals for assistive communication devices. While previous pre-clinical and clinical studies have demonstrated promising proofs-of-concept (Serruya et al., 2002; Simeral et al., 2011; Bacher et al., 2015; Nuyujukian et al., 2015; Aflalo et al., 2015; Gilja et al., 2015; Jarosiewicz et al., 2015; Wolpaw et al., 1998; Hwang et al., 2012; Spüler et al., 2012; Leuthardt et al., 2004; Taylor et al., 2002; Schalk et al., 2008; Moran, 2010; Brunner et al., 2011; Wang et al., 2013; Townsend and Platsko, 2016; Vansteensel et al., 2016; Nuyujukian et al., 2016; Carmena et al., 2003; Musallam et al., 2004; Santhanam et al., 2006; Hochberg et al., 2006; Ganguly et al., 2011; O'Doherty et al., 2011; Gilja et al., 2012), the performance of human clinical BCI systems is not yet high enough to support widespread adoption by people with physical limitations of speech. Here we report a high-performance intracortical BCI (iBCI) for communication, which was tested by three clinical trial participants with paralysis. The system leveraged advances in decoder design developed in prior pre-clinical and clinical studies (Gilja et al., 2015; Kao et al., 2016; Gilja et al., 2012). For all three participants, performance exceeded previous iBCIs (Bacher et al., 2015; Jarosiewicz et al., 2015) as measured by typing rate (by a factor of 1.4-4.2) and information throughput (by a factor of 2.2-4.0). This high level of performance demonstrates the potential utility of iBCIs as powerful assistive communication devices for people with limited motor function.Clinical Trial No: NCT00912041.
Simultaneous modeling of habitat suitability, occupancy, and relative abundance: African elephants in Zimbabwe.
Martin, Julien; Chamaillé-Jammes, Simon; Nichols, James D; Fritz, Hervé; Hines, James E; Fonnesbeck, Christopher J; MacKenzie, Darryl I; Bailey, Larissa L
The recent development of statistical models such as dynamic site occupancy models provides the opportunity to address fairly complex management and conservation problems with relatively simple models. However, surprisingly few empirical studies have simultaneously modeled habitat suitability and occupancy status of organisms over large landscapes for management purposes. Joint modeling of these components is particularly important in the context of management of wild populations, as it provides a more coherent framework to investigate the population dynamics of organisms in space and time for the application of management decision tools. We applied such an approach to the study of water hole use by African elephants in Hwange National Park, Zimbabwe. Here we show how such methodology may be implemented and derive estimates of annual transition probabilities among three dry-season states for water holes: (1) unsuitable state (dry water holes with no elephants); (2) suitable state (water hole with water) with low abundance of elephants; and (3) suitable state with high abundance of elephants. We found that annual rainfall and the number of neighboring water holes influenced the transition probabilities among these three states. Because of an increase in elephant densities in the park during the study period, we also found that transition probabilities from low abundance to high abundance states increased over time. The application of the joint habitat-occupancy models provides a coherent framework to examine how habitat suitability and factors that affect habitat suitability influence the distribution and abundance of organisms. We discuss how these simple models can further be used to apply structured decision-making tools in order to derive decisions that are optimal relative to specified management objectives. The modeling framework presented in this paper should be applicable to a wide range of existing data sets and should help to address important ecological
Improving Spacecraft Data Visualization Using Splunk
NASA Technical Reports Server (NTRS)
Conte, Matthew
EPOXI, like all spacecraft missions, receives large volumes of telemetry data from its spacecraft, DIF. It is extremely important for this data to be updated quickly and presented in a readable manner so that the flight team can monitor the status of the spacecraft. Existing DMD pages for monitoring spacecraft telemetry, while functional, are limited and do not take advantage of modern search technology. For instance, they only display current data points from instruments on the spacecraft and have limited graphing capabilities, making it difficult to see historical data. The DMD pages have fixed refresh rates so the team must often wait several minutes to see the most recent data, even after it is received on the ground. The pages are also rigid and require an investment of time and money to update. To more easily organize and visualize spacecraft telemetry, the EPOXI team has begun experimenting with Splunk, a commercially-available data mining system. Splunk can take data received from the spacecraft's different data channels, often in different formats, and index all the data into a common format. Splunk allows flight team members to search through the different data formats from a single interface and to filter results by time range and data field to make finding specific spacecraft events quick and easy. Furthermore, Splunk provides functions to create custom interfaces which help team members visualize the data in charts and graphs to show how the health of the spacecraft has changed over time.One of the goals of my internship with my mentor, Victor Hwang, was to develop new Splunk interfaces to replace the DMD pages and give the spacecraft team access to historical data and visualizations that were previously unavailable. The specific requirements of these pages are discussed in the next section.
Serum complexes of insulin-like growth factor-1 modulate skeletal integrity and carbohydrate metabolism
Yakar, Shoshana; Rosen, Clifford J.; Bouxsein, Mary L.; Sun, Hui; Mejia, Wilson; Kawashima, Yuki; Wu, Yingjie; Emerton, Kelly; Williams, Valerie; Jepsen, Karl; Schaffler, Mitchell B.; Majeska, Robert J.; Gavrilova, Oksana; Gutierrez, Mariana; Hwang, David; Pennisi, Patricia; Frystyk, Jan; Boisclair, Yves; Pintar, John; Jasper, Héctor; Domene, Horacio; Cohen, Pinchas; Clemmons, David; LeRoith, Derek
Serum insulin-like growth factor (IGF) -1 is secreted mainly by the liver and circulates bound to IGF-binding proteins (IGFBPs), either as binary complexes or ternary complexes with IGFBP-3 or IGFBP-5 and an acid-labile subunit (ALS). The purpose of this study was to genetically dissect the role of IGF-1 circulatory complexes in somatic growth, skeletal integrity, and metabolism. Phenotypic comparisons of controls and four mouse lines with genetic IGF-1 deficits—liver-specific IGF-1 deficiency (LID), ALS knockout (ALSKO), IGFBP-3 (BP3) knockout, and a triply deficient LID/ALSKO/BP3 line—produced several novel findings. 1) All deficient strains had decreased serum IGF-1 levels, but this neither predicted growth potential or skeletal integrity nor defined growth hormone secretion or metabolic abnormalities. 2) IGF-1 deficiency affected development of both cortical and trabecular bone differently, effects apparently dependent on the presence of different circulating IGF-1 complexes. 3) IGFBP-3 deficiency resulted in increased linear growth. In summary, each IGF-1 complex constituent appears to play a distinct role in determining skeletal phenotype, with different effects on cortical and trabecular bone compartments.—Yakar, S., Rosen, C. J., Bouxsein, M. L., Sun, H., Mejia, W., Kawashima, Y., Wu, Y., Emerton, K., Williams, V., Jepsen, K., Schaffler, M. B., Majeska, R. J., Gavrilova, O., Gutierrez, M., Hwang, D., Pennisi, P., Frystyk, J., Boisclair, Y., Pintar, J., Jasper, H., Domene, H., Cohen, P., Clemmons, D., LeRoith, D. Serum complexes of insulin-like growth factor-1 modulate skeletal integrity and carbohydrate metabolism. PMID:18952711
Improving the Accuracy of a Heliocentric Potential (HCP) Prediction Model for the Aviation Radiation Dose
NASA Astrophysics Data System (ADS)
Hwang, Junga; Yoon, Kyoung-Won; Jo, Gyeongbok; Noh, Sung-Jun
The space radiation dose over air routes including polar routes should be carefully considered, especially when space weather shows sudden disturbances such as coronal mass ejections (CMEs), flares, and accompanying solar energetic particle events. We recently established a heliocentric potential (HCP) prediction model for real-time operation of the CARI-6 and CARI-6M programs. Specifically, the HCP value is used as a critical input value in the CARI-6/6M programs, which estimate the aviation route dose based on the effective dose rate. The CARI-6/6M approach is the most widely used technique, and the programs can be obtained from the U.S. Federal Aviation Administration (FAA). However, HCP values are given at a one month delay on the FAA official webpage, which makes it difficult to obtain real-time information on the aviation route dose. In order to overcome this critical limitation regarding the time delay for space weather customers, we developed a HCP prediction model based on sunspot number variations (Hwang et al. 2015). In this paper, we focus on improvements to our HCP prediction model and update it with neutron monitoring data. We found that the most accurate method to derive the HCP value involves (1) real-time daily sunspot assessments, (2) predictions of the daily HCP by our prediction algorithm, and (3) calculations of the resultant daily effective dose rate. Additionally, we also derived the HCP prediction algorithm in this paper by using ground neutron counts. With the compensation stemming from the use of ground neutron count data, the newly developed HCP prediction model was improved.
Seasonal diet and prey preference of the African lion in a waterhole-driven semi-arid savanna.
Davidson, Zeke; Valeix, Marion; Van Kesteren, Freya; Loveridge, Andrew J; Hunt, Jane E; Murindagomo, Felix; Macdonald, David W
Large carnivores inhabiting ecosystems with heterogeneously distributed environmental resources with strong seasonal variations frequently employ opportunistic foraging strategies, often typified by seasonal switches in diet. In semi-arid ecosystems, herbivore distribution is generally more homogeneous in the wet season, when surface water is abundant, than in the dry season when only permanent sources remain. Here, we investigate the seasonal contribution of the different herbivore species, prey preference and distribution of kills (i.e. feeding locations) of African lions in Hwange National Park, Zimbabwe, a semi-arid African savanna structured by artificial waterholes. We used data from 245 kills and 74 faecal samples. Buffalo consistently emerged as the most frequently utilised prey in all seasons by both male (56%) and female (33%) lions, contributing the most to lion dietary biomass. Jacobs' index also revealed that buffalo was the most intensively selected species throughout the year. For female lions, kudu and to a lesser extent the group "medium Bovidae" are the most important secondary prey. This study revealed seasonal patterns in secondary prey consumption by female lions partly based on prey ecology with browsers, such as giraffe and kudu, mainly consumed in the early dry season, and grazers, such as zebra and suids, contributing more to female diet in the late dry season. Further, it revealed the opportunistic hunting behaviour of lions for prey as diverse as elephants and mice, with elephants taken mostly as juveniles at the end of the dry season during droughts. Jacobs' index finally revealed a very strong preference for kills within 2 km from a waterhole for all prey species, except small antelopes, in all seasons. This suggested that surface-water resources form passive traps and contribute to the structuring of lion foraging behaviour.
Key Residues of Outer Membrane Protein OprI Involved in Hexamer Formation and Bacterial Susceptibility to Cationic Antimicrobial Peptides.
Chang, Ting-Wei; Wang, Chiu-Feng; Huang, Hsin-Jye; Wang, Iren; Hsu, Shang-Te Danny; Liao, You-Di
Antimicrobial peptides (AMPs) are important components of the host innate defense mechanism against invading pathogens. Our previous studies have shown that the outer membrane protein, OprI from Pseudomonas aeruginosa or its homologue, plays a vital role in the susceptibility of Gram-negative bacteria to cationic α-helical AMPs (Y. M. Lin, S. J. Wu, T. W. Chang, C. F. Wang, C. S. Suen, M. J. Hwang, M. D. Chang, Y. T. Chen, Y. D. Liao, J Biol Chem 285:8985-8994, 2010, http://dx.doi.org/10.1074/jbc.M109.078725; T. W. Chang, Y. M. Lin, C. F. Wang, Y. D. Liao, J Biol Chem 287:418-428, 2012, http://dx.doi.org/10.1074/jbc.M111.290361). Here, we obtained two forms of recombinant OprI: rOprI-F, a hexamer composed of three disulfide-bridged dimers, was active in AMP binding, while rOprI-R, a trimer, was not. All the subunits predominantly consisted of α-helices and exhibited rigid structures with a melting point centered around 76°C. Interestingly, OprI tagged with Escherichia coli signal peptide was expressed in a hexamer, which was anchored on the surface of E. coli, possibly through lipid acids added at the N terminus of OprI and involved in the binding and susceptibility to AMP as native P. aeruginosa OprI. Deletion and mutation studies showed that Cys1 and Asp27 played a key role in hexamer formation and AMP binding, respectively. The increase of OprI hydrophobicity upon AMP binding revealed that it undergoes conformational changes for membrane fusion. Our results showed that OprI on bacterial surfaces is responsible for the recruitment and susceptibility to amphipathic α-helical AMPs and may be used to screen antimicrobials.
Asymptotics of bivariate generating functions with algebraic singularities
NASA Astrophysics Data System (ADS)
Greenwood, Torin
Flajolet and Odlyzko (1990) derived asymptotic formulae the coefficients of a class of uni- variate generating functions with algebraic singularities. Gao and Richmond (1992) and Hwang (1996, 1998) extended these results to classes of multivariate generating functions, in both cases by reducing to the univariate case. Pemantle and Wilson (2013) outlined new multivariate ana- lytic techniques and used them to analyze the coefficients of rational generating functions. After overviewing these methods, we use them to find asymptotic formulae for the coefficients of a broad class of bivariate generating functions with algebraic singularities. Beginning with the Cauchy integral formula, we explicity deform the contour of integration so that it hugs a set of critical points. The asymptotic contribution to the integral comes from analyzing the integrand near these points, leading to explicit asymptotic formulae. Next, we use this formula to analyze an example from current research. In the following chapter, we apply multivariate analytic techniques to quan- tum walks. Bressler and Pemantle (2007) found a (d + 1)-dimensional rational generating function whose coefficients described the amplitude of a particle at a position in the integer lattice after n steps. Here, the minimal critical points form a curve on the (d + 1)-dimensional unit torus. We find asymptotic formulae for the amplitude of a particle in a given position, normalized by the number of steps n, as n approaches infinity. Each critical point contributes to the asymptotics for a specific normalized position. Using Groebner bases in Maple again, we compute the explicit locations of peak amplitudes. In a scaling window of size the square root of n near the peaks, each amplitude is asymptotic to an Airy function.
Frequent summer droughts homogenize landscape vegetation patterns at the catchment scale
NASA Astrophysics Data System (ADS)
Hwang, T.; Band, L. E.; Miniat, C. F.; Song, C.
Mountain watersheds are primary sources of freshwater, carbon sequestration, and other ecosystem services. There is significant interest in the effects of climate change and variability on the patterns and processes of these services over short to long time scales. Forest ecosystems are sensitive to interannual to long-term hydroclimate variability and they adjust leaf area and duration in response to water or nutrient availability. Therefore, much of the impact of hydroclimate variability and resulting water yield is manifested in vegetation dynamics in space and time since they provide 'a window into the underlying water balance' (Sivapalan, 2005). Landsat TM provides a three-decade multispectral imagery record which enables us to estimate changes in landscape vegetation patterns at fine resolution (30 m) over the period of global warming. We characterize the catchment-scale vegetation patterns with the ';hydrologic vegetation gradient (HVG)' (defined as the gradient of the normalized difference vegetation index (NDVI) along hydrologic flowpaths; Hwang et al., 2012) and the standard deviations of NDVI from historic Landsat TM images at six preserved headwater catchments in Coweeta Hydrologic Laboratory, NC. We also analyze long-term seasonal water balances and low flow patterns from observed hydrologic records. We found that vegetation gradients along hydrologic flowpaths have decreased with hydroclimate change due to the decreases in upslope subsidies. This study shows that forest ecosystems are responding to the variability in hydroclimate regime rather than the mean, especially to drought. This study provides mechanistic understanding of shifts in hydrologic and ecologic regimes in humid mountainous landscapes with hydroclimate change. It also presents the potential to use emergent vegetation patterns in space and time for the inference of long-term hydrologic behavior. Figure 1. Temporal patterns of the hydrologic vegetation gradient and standard deviations
Brain Gray Matter Deficits in Patients with Chronic Primary Insomnia
Joo, Eun Yeon; Noh, Hyun Jin; Kim, Jeong-Sik; Koo, Dae Lim; Kim, Daeyoung; Hwang, Kyoung Jin; Kim, Ji Young; Kim, Sung Tae; Kim, Mi Rim; Hong, Seung Bong
Study Objective: To investigate the structural changes in patients with chronic primary insomnia and the relationships with clinical features of insomnia. Design: Statistical parametric mapping 8-based voxel-based morphometry was used to identify differences in regional gray and white matter between patients with chronic primary insomnia and normal controls. Setting: University hospital. Patients and Participants: Twenty-seven patients and 27 age/sex-matched controls. Interventions: Regional differences were compared using two-sample t-tests with age, sex, and intracranial volume as covariates. Measurements and Results: The patients were a mean age of 52.3 y and had a mean history of insomnia of 7.6 y. Patients displayed cognitive deficits in attention, frontal/executive function, and nonverbal memory. Patients also displayed significantly reduced gray matter concentrations (GMCs) in dorsolateral prefrontal and pericentral cortices, superior temporal gyrus, and cerebellum and decreased gray matter volumes in medial frontal and middle temporal gyri compared with control patients with the cluster threshold ≥ 50 voxels at the level of uncorrected P < 0.001. Negative correlations were found between GMC of the prefrontal cortex and insomnia severity and the wakefulness after sleep onset, and between GMC of pericentral cortex and sleep latencies. None of the findings continued to be significant after correction for multiple comparisons. Conclusions: We found gray matter deficits in multiple brain regions including bilateral frontal lobes in patients with psychophysiologic insomnia. Gray matter deficit of the pericentral and lateral temporal areas may be associated with the difficulties in sleep initiation and maintenance. It is still unclear whether gray matter reductions are a preexisting abnormality or a consequence of insomnia. Citation: Joo EY; Noh HJ; Kim JS; Koo DL; Kim D; Hwang KJ; Kim JY; Kim ST; Kim MR; Hong SB. Brain gray matter deficits in patients with
Protocol for a between-group experimental study examining cultural differences in emotion processing between Malay and Caucasian adults with and without major depressive disorder
Mohan, S N; Mukhtar, F; Jobson, L
Introduction Depression is a mood disorder that affects a significant proportion of the population worldwide. In Malaysia and Australia, the number of people diagnosed with depression is on the rise. It has been found that impairments in emotion processing and emotion regulation play a role in the development and maintenance of depression. This study is based on Matsumoto and Hwang's biocultural model of emotion and Triandis' Subjective Culture model. It aims to investigate the influence of culture on emotion processing among Malaysians and Australians with and without major depressive disorder (MDD). Methods and analysis This study will adopt a between-group design. Participants will include Malaysian Malays and Caucasian Australians with and without MDD (N=320). There will be four tasks involved in this study, namely: (1) the facial emotion recognition task, (2) the biological motion task, (3) the subjective experience task and (4) the emotion meaning task. It is hypothesised that there will be cultural differences in how participants with and without MDD respond to these emotion tasks and that, pan-culturally, MDD will influence accuracy rates in the facial emotion recognition task and the biological motion task. Ethics and dissemination This study is approved by the Universiti Putra Malaysia Research Ethics Committee (JKEUPM) and the Monash University Human Research Ethics Committee (MUHREC). Permission to conduct the study has also been obtained from the National Medical Research Register (NMRR; NMRR-15-2314-26919). On completion of the study, data will be kept by Universiti Putra Malaysia for a specific period of time before they are destroyed. Data will be published in a collective manner in the form of journal articles with no reference to a specific individual. PMID:27798019
Escherichia coli Population Structure and Antibiotic Resistance at a Buffalo/Cattle Interface in Southern Africa
Mercat, Mathilde; Clermont, Olivier; Massot, Méril; Ruppe, Etienne; de Garine-Wichatitsky, Michel; Miguel, Eve; Valls Fox, Hugo; Cornelis, Daniel; Andremont, Antoine; Denamur, Erick
At a human/livestock/wildlife interface, Escherichia coli populations were used to assess the risk of bacterial and antibiotic resistance dissemination between hosts. We used phenotypic and genotypic characterization techniques to describe the structure and the level of antibiotic resistance of E. coli commensal populations and the resistant Enterobacteriaceae carriage of sympatric African buffalo (Syncerus caffer caffer) and cattle populations characterized by their contact patterns in the southern part of Hwange ecosystem in Zimbabwe. Our results (i) confirmed our assumption that buffalo and cattle share similar phylogroup profiles, dominated by B1 (44.5%) and E (29.0%) phylogroups, with some variability in A phylogroup presence (from 1.9 to 12%); (ii) identified a significant gradient of antibiotic resistance from isolated buffalo to buffalo in contact with cattle and cattle populations expressed as the Murray score among Enterobacteriaceae (0.146, 0.258, and 0.340, respectively) and as the presence of tetracycline-, trimethoprim-, and amoxicillin-resistant subdominant E. coli strains (0, 5.7, and 38%, respectively); (iii) evidenced the dissemination of tetracycline, trimethoprim, and amoxicillin resistance genes (tet, dfrA, and blaTEM-1) in 26 isolated subdominant E. coli strains between nearby buffalo and cattle populations, that led us (iv) to hypothesize the role of the human/animal interface in the dissemination of genetic material from human to cattle and toward wildlife. The study of antibiotic resistance dissemination in multihost systems and at anthropized/natural interface is necessary to better understand and mitigate its multiple threats. These results also contribute to attempts aiming at using E. coli as a tool for the identification of pathogen transmission pathway in multihost systems. PMID:26712551
Atomic-Scale Chemical Imaging of Composition and Bonding at Perovskite Oxide Interfaces
NASA Astrophysics Data System (ADS)
Fitting Kourkoutis, L.
Scanning transmission electron microscopy (STEM) in combination with electron energy loss spectroscopy (EELS) has proven to be a powerful technique to study buried perovskite oxide heterointerfaces. With the recent addition of 3^rd order and now 5^th order aberration correction, which provides a factor of 100x increase in signal over an uncorrected system, we are now able to record 2D maps of composition and bonding of oxide interfaces at atomic resolution [1]. Here, we present studies of the microscopic structure of oxide/oxide multilayers and heterostructures by STEM in combination with EELS and its effect on the properties of the film. Using atomic-resolution spectroscopic imaging we show that the degradation of the magnetic and transport properties of La0.7Sr0.3MnO3/SrTiO3 multilayers correlates with atomic intermixing at the interfaces and the presence of extended defects in the La0.7Sr0.3MnO3 layers. When these defects are eliminated, metallic ferromagnetism at room temperature can be stabilized in 5 unit cell thick manganite layers, almost 40% thinner than the previously reported critical thickness of 3-5 nm for sustaining metallic ferromagnetism below Tc in La0.7Sr0.3MnO3 thin films grown on SrTiO3.[4pt] [1] D.A. Muller, L. Fitting Kourkoutis, M. Murfitt, J.H. Song, H.Y. Hwang, J. Silcox, N. Dellby, O.L. Krivanek, Science 319, 1073-1076 (2008).
3D strain measurement in soft tissue: demonstration of a novel inverse finite element model algorithm on MicroCT images of a tissue phantom exposed to negative pressure wound therapy.
Wilkes, R; Zhao, Y; Cunningham, K; Kieswetter, K; Haridas, B
This study describes a novel system for acquiring the 3D strain field in soft tissue at sub-millimeter spatial resolution during negative pressure wound therapy (NPWT). Recent research in advanced wound treatment modalities theorizes that microdeformations induced by the application of sub-atmospheric (negative) pressure through V.A.C. GranuFoam Dressing, a reticulated open-cell polyurethane foam (ROCF), is instrumental in regulating the mechanobiology of granulation tissue formation [Saxena, V., Hwang, C.W., Huang, S., Eichbaum, Q., Ingber, D., Orgill, D.P., 2004. Vacuum-assisted closure: Microdeformations of wounds and cell proliferation. Plast. Reconstr. Surg. 114, 1086-1096]. While the clinical response is unequivocal, measurement of deformations at the wound-dressing interface has not been possible due to the inaccessibility of the wound tissue beneath the sealed dressing. Here we describe the development of a bench-test wound model for microcomputed tomography (microCT) imaging of deformation induced by NPWT and an algorithm set for quantifying the 3D strain field at sub-millimeter resolution. Microdeformations induced in the tissue phantom revealed average tensile strains of 18%-23% at sub-atmospheric pressures of -50 to -200 mmHg (-6.7 to -26.7 kPa). The compressive strains (22%-24%) and shear strains (20%-23%) correlate with 2D FEM studies of microdeformational wound therapy in the reference cited above. We anticipate that strain signals quantified using this system can then be used in future research aimed at correlating the effects of mechanical loading on the phenotypic expression of dermal fibroblasts in acute and chronic ulcer models. Furthermore, the method developed here can be applied to continuum deformation analysis in other contexts, such as 3D cell culture via confocal microscopy, full scale CT and MRI imaging, and in machine vision.
Upper limit to magnetism in LaAlO3/SrTiO3 heterostructures
NASA Astrophysics Data System (ADS)
Fitzsimmons, Michael
In 2004 Ohtomo and Hwang reported unusually high conductivity in LaAlO3 and SrTiO3 bilayer samples. Since then, metallic conduction, superconductivity, magnetism, and coexistence of superconductivity and ferromagnetism have been attributed to LaAlO3/SrTiO3 interfaces. Very recently, two studies have reported large magnetic moments attributed to interfaces from measurement techniques that are unable to distinguish between interfacial and bulk magnetism. Consequently, it is imperative to perform magnetic measurements that by being intrinsically sensitive to interface magnetism are impervious to experimental artifacts suffered by bulk measurements. Using polarized neutron reflectometry, we measured the neutron spin dependent reflectivity from four LaAlO3/SrTiO3 superlattices. Our results indicate the upper limit for the magnetization averaged over the lateral dimensions of the sample induced by an 11 T magnetic field at 1.7 K is less than 2 G. SQUID magnetometry of the neutron superlattice samples sporadically finds an enhanced moment (consistent with past reports), possibly due to experimental artifacts. These observations set important restrictions on theories which imply a strongly enhanced magnetism at the interface between LaAlO3 and SrTiO3. Work performed in collaboration with N.W. Hengartner, S. Singh, M. Zhernenkov (LANL), F.Y. Bruno, J. Santamaria (Universidad Complutense de Madrid), A. Brinkman, M.J.A. Huijben, H. Molegraaf (MESA+ Institute for Nanotechnology), J. de la Venta and Ivan K. Schuller (UCSD). [4pt] Work supported by the Office of Basic Energy Science, U.S. Department of Energy, BES-DMS and DMR under grant DE FG03-87ER-45332. Work at UCM is supported by Consolider Ingenio CSD2009-00013 (IMAGINE), CAM S2009-MAT 1756 (PHAMA) and work at Twente is supported by the Foundation for Fundamental Research on Matter (FOM).
Relationship between Kleine-Levin Syndrome and Upper Respiratory Infection in Taiwan
Huang, Yu-Shu; Guilleminault, Christian; Lin, Kuang-Lin; Hwang, Fang-Ming; Liu, Feng-Yuan; Kung, Yen-Ping
Study Objectives: In Kleine-Levin Syndrome (KLS), new episodes of hypersomnia are often preceded by an acute flu-like syndrome or upper airway infection 3 to 5 days before onset. This study investigated the relationship between the occurrence of mild upper respiratory tract infections (URIs) in the general population and the occurrence and seasonality and hypersomnic episodes in KLS patients. Design: This investigation was a longitudinal clinical study. Based on data obtained from the National Health Research Institutes between 2006 and 2007, the timing of hypersomnic episodes in 30 KLS patients were compared with calendar reports of URI events, and the results compared with age-matched general Taiwanese population. Measurements: Clinical symptoms, physical examination, polysomnographic recording, SPECT study, and laboratory tests affirming KLS during both periods of hypersomnic attack and non-attack were collected. Every symptomatic episode was then followed up. The cross-correlation function (CCF) and bivariate correlations analysis were performed to see the relationship between KLS and URIs. Results: A positive finding of CCF analysis and significant bivariate correlations were found between KLS episodes and URI in the general population (r = 0.456*). In onset of hypersomnia, significant correlations existed among "acute upper respiratory infections" (r = 0.446*), "acute bronchitis and bronchiolitis" (r = 0.462*), and "pharyngitis and nasopharyngitis" (r = 0.548*) subtypes of infections. A positive correlation between higher reports of symptomatic hypersomnia and URI also existed in a given season. A positive nonsignificant trend for "allergic rhinitis" (r = 0.400) was also found. Conclusion: The agent behind URI or its consequence (such as fever) is associated with increased incidence of KLS episodes and may explain periodic symptomatic recurrences. Citation: Huang YS; Guilleminault C; Lin KL Hwang FM; Liu FY; Kung YP. Relationship between
CO2 Laser Beat-Wave Experiment in an Unmagnetized Plasma
NASA Astrophysics Data System (ADS)
Liu, Fei; Hwang, David; Horton, Robert; Hong, Sean; Evans, Russell
The ability to remotely generate plasma current in dense plasmas is a basic yet important investigation in experimental plasma physics and fusion energy research. It is even more advantageous if the wave penetration is independent of the electron acceleration process. Plasma current can be generated through beat-wave mixing process by launching two intense electromagnetic waves (φ>>φpe) into plasma. The beat wave formation process can be efficient if the difference frequency of the two pump waves is matched to a local resonant frequency of the medium, i.e. in this case the local plasma frequency. Beat wave can accelerate plasma electrons via quasi-linear Landau process, which has been demonstrated in a low-density plasma using microwaves.footnotetextRogers, J. H. and Hwang, D. Q., Phys. Rev. Lett. v68 p3877 (1992). The CO2 lasers provide the high tunability for the wave-particle interaction experiment at a variety of plasma densities with plasma frequency in THz range. Two sections of Lumonics TEA CO2 lasers have been modified to serve as the two pump wave sources with peak power over 100MW. The development of the tunable CO2 lasers, a high-density plasma target source and diagnostics system will be presented. The initial results of unbalanced beat-wave experiment using one high-power pulsed and one low-power CW CO2 lasers will be presented and discussed using the independent plasma source to control the φpe of the interaction region. This work is supported by U.S. DOE under Contract No. DE-FG02-10ER55083.
Nitric oxide signaling in Pseudomonas aeruginosa biofilms mediates phosphodiesterase activity, decreased cyclic di-GMP levels, and enhanced dispersal.
Barraud, Nicolas; Schleheck, David; Klebensberger, Janosch; Webb, Jeremy S; Hassett, Daniel J; Rice, Scott A; Kjelleberg, Staffan
Bacteria in biofilms often undergo active dispersal events and revert to a free-swimming, planktonic state to complete the biofilm life cycle. The signaling molecule nitric oxide (NO) was previously found to trigger biofilm dispersal in the opportunistic pathogen Pseudomonas aeruginosa at low, nontoxic concentrations (N. Barraud, D. J. Hassett, S. H. Hwang, S. A. Rice, S. Kjelleberg, and J. S. Webb, J. Bacteriol. 188:7344-7353, 2006). NO was further shown to increase cell motility and susceptibility to antimicrobials. Recently, numerous studies revealed that increased degradation of the secondary messenger cyclic di-GMP (c-di-GMP) by specific phosphodiesterases (PDEs) triggers a planktonic mode of growth in eubacteria. In this study, the potential link between NO and c-di-GMP signaling was investigated by performing (i) PDE inhibitor studies, (ii) enzymatic assays to measure PDE activity, and (iii) direct quantification of intracellular c-di-GMP levels. The results suggest a role for c-di-GMP signaling in triggering the biofilm dispersal event induced by NO, as dispersal requires PDE activity and addition of NO stimulates PDE and induces the concomitant decrease in intracellular c-di-GMP levels in P. aeruginosa. Furthermore, gene expression studies indicated global responses to low, nontoxic levels of NO in P. aeruginosa biofilms, including upregulation of genes involved in motility and energy metabolism and downregulation of adhesins and virulence factors. Finally, site-directed mutagenesis of candidate genes and physiological characterization of the corresponding mutant strains uncovered that the chemotaxis transducer BdlA is involved in the biofilm dispersal response induced by NO.
Teleseismic Peak Ground Accelerations from the 24 May 2013 Sea of Okhotsk Deep Earthquake
NASA Astrophysics Data System (ADS)
Kuge, K.
The 2013 Sea of Okhotsk deep earthquake (Mw8.3) generated felt reports worldwide including ones from Moscow (~58 degrees) and Dubai (~76 degrees) (NEIC, 2013). The earthquake was recorded by many global seismic stations with a good coverage of azimuth and distance, which provides an opportunity to understand the global characteristics of ground shaking. Peak ground accelerations (PGA) from the Sea of Okhotsk deep earthquake decrease with distance up to 120 degrees, and have a peak at a distance of 140-150 degrees. The variation as a function of distance is similar to the one shown by Anderson et al. (1995) for the 1994 Bolivia earthquake. PGA at distances between 40 and 85 degrees are associated with vertical components of direct P waves, and the values are mostly in a range from 0.1 to 1 gal. The decay with distance is in agreement with that of P wave amplitude predicted by the ray theory with t* in the range between the lower-mantle attenuation models of Hwang and Ritsema (2011) and PREM. Frequencies characterizing the PGA decay are in a range between 0.8 and 1.8 Hz. As also suggested by observations from other large deep earthquakes, the radiation pattern of P waves can change the decay curves of PGA with distance, by affecting the amplitude of P waves in the frequency range. Spatial variations of PGA are likely to be characterized by the tectonic setting; large values of PGA appear in stable continents and old seas, whereas small values are observed in tectonically active regions. Positive correlation is observed between PGA values and velocity perturbations of the 3-D global shear velocity model at depths shallower than 100 km.
Elongation factor Tu D138N, a mutant with modified substrate specificity, as a tool to study energy consumption in protein biosynthesis.
Weijland, A; Parlato, G; Parmeggiani, A
Substitution Asp138-->Asn changes the substrate specificity of elongation factor (EF) Tu from GTP to XTP [Hwang & Miller (1987) J. Biol. Chem. 262, 13081-13085]. This mutated EF-Tu (EF-Tu D138N) was used to show that 2 XTP molecules are hydrolyzed for each elongation cycle [Weijland & Parmeggiani (1993) Science 259, 1311-1313]. Here we extend the study of the properties of this EF-Tu mutant and its function in the elongation process. In poly(U)-directed poly(phenylalanine) synthesis, the number of peptide chains synthesized using EF-Tu D138N.XTP was 30% higher than with EF-Tu wild type (wt).GTP. However, since in the former case the average peptide chain length was correspondingly reduced, the number of the residues incorporated turned out to be nearly the same in both systems. The K'd values of the XTP and XDP complexes of EF-Tu D138N were similar to those of the GTP and GDP complexes of EF-Tu wt. The extent of leucine misincorporation and the kirromycin effect were also comparable to those in the EF-Tu wt/GTP system. The hydrolysis of two XTP molecules, very likely as part of two EF-Tu D138N.XTP complexes, for each elongation cycle was found to be independent of (i) MgCl2 concentration, (ii) ribosome concentration, and (iii) temperature (5-40 degrees C). With rate-limiting amounts of XTP the K'm of its XTPase activity corresponded to the K'm for XTP of poly(phenylalanine) synthesis (0.3-0.6 microM).(ABSTRACT TRUNCATED AT 250 WORDS)
Simultaneous modeling of habitat suitability, occupancy, and relative abundance: African elephants in Zimbabwe
Martin, Julien; Chamaille-Jammes, Simon; Nichols, James D.; Fritz, Herve; Hines, James E.; Fonnesbeck, Christopher J.; MacKenzie, Darryl I.; Bailey, Larissa L.
The recent development of statistical models such as dynamic site occupancy models provides the opportunity to address fairly complex management and conservation problems with relatively simple models. However, surprisingly few empirical studies have simultaneously modeled habitat suitability and occupancy status of organisms over large landscapes for management purposes. Joint modeling of these components is particularly important in the context of management of wild populations, as it provides a more coherent framework to investigate the population dynamics of organisms in space and time for the application of management decision tools. We applied such an approach to the study of water hole use by African elephants in Hwange National Park, Zimbabwe. Here we show how such methodology may be implemented and derive estimates of annual transition probabilities among three dry-season states for water holes: (1) unsuitable state (dry water holes with no elephants); (2) suitable state (water hole with water) with low abundance of elephants; and (3) suitable state with high abundance of elephants. We found that annual rainfall and the number of neighboring water holes influenced the transition probabilities among these three states. Because of an increase in elephant densities in the park during the study period, we also found that transition probabilities from low abundance to high abundance states increased over time. The application of the joint habitat–occupancy models provides a coherent framework to examine how habitat suitability and factors that affect habitat suitability influence the distribution and abundance of organisms. We discuss how these simple models can further be used to apply structured decision-making tools in order to derive decisions that are optimal relative to specified management objectives. The modeling framework presented in this paper should be applicable to a wide range of existing data sets and should help to address important ecological
Octadecabacterponticola sp. nov., isolated from seawater.
Park, Sooyeon; Yoon, Sun Young; Jung, Yong-Taek; Yoon, Jung-Hoon
A Gram-stain-negative, non-spore-forming, non-flagellated and coccoid, ovoid or rod-shaped bacterial strain, HDSW-34T, was isolated from seawater of Hwang-do on the Yellow Sea, South Korea, and subjected to a taxonomic study using a polyphasic approach. Strain HDSW-34T grew optimally at 30 °C, at pH 7.0-8.0 and in the presence of 1.0-2.0 % (w/v) NaCl. Neighbour-joining, maximum-likelihood and maximum-parsimony phylogenetic trees based on 16S rRNA gene sequences revealed that strain HDSW-34Tclustered with the type strains of four species of the genus Octadecabacter, showing 96.7-97.6 % sequence similarity. Strain HDSW-34T contained Q-10 as the predominant ubiquinone and C18 : 1ω7c as the major fatty acid. The major polar lipids detected in strain HDSW-34T were phosphatidylcholine, phosphatidylglycerol, one unidentified aminolipid and one unidentified lipid. The DNA G+C content of strain HDSW-34T was 62.0 mol% and its DNA-DNA relatedness values with Octadecabacterantarcticus CIP 106731T and Octadecabacterarcticus DSM 13978T were 11-18 %. The differential phenotypic properties, together with the phylogenetic and genetic distinctiveness, revealed that strain HDSW-34T is separated from other recognized species of the genus Octadecabacter. On the basis of the data presented, strain HDSW-34T is considered to represent a novel species of the genus Octadecabacter, for which the name Octadecabacterponticola sp. nov. is proposed. The type strain is HDSW-34T (= KCTC 52250T=NBRC 112296T).
Escherichia coli Population Structure and Antibiotic Resistance at a Buffalo/Cattle Interface in Southern Africa.
Mercat, Mathilde; Clermont, Olivier; Massot, Méril; Ruppe, Etienne; de Garine-Wichatitsky, Michel; Miguel, Eve; Valls Fox, Hugo; Cornelis, Daniel; Andremont, Antoine; Denamur, Erick; Caron, Alexandre
At a human/livestock/wildlife interface, Escherichia coli populations were used to assess the risk of bacterial and antibiotic resistance dissemination between hosts. We used phenotypic and genotypic characterization techniques to describe the structure and the level of antibiotic resistance of E. coli commensal populations and the resistant Enterobacteriaceae carriage of sympatric African buffalo (Syncerus caffer caffer) and cattle populations characterized by their contact patterns in the southern part of Hwange ecosystem in Zimbabwe. Our results (i) confirmed our assumption that buffalo and cattle share similar phylogroup profiles, dominated by B1 (44.5%) and E (29.0%) phylogroups, with some variability in A phylogroup presence (from 1.9 to 12%); (ii) identified a significant gradient of antibiotic resistance from isolated buffalo to buffalo in contact with cattle and cattle populations expressed as the Murray score among Enterobacteriaceae (0.146, 0.258, and 0.340, respectively) and as the presence of tetracycline-, trimethoprim-, and amoxicillin-resistant subdominant E. coli strains (0, 5.7, and 38%, respectively); (iii) evidenced the dissemination of tetracycline, trimethoprim, and amoxicillin resistance genes (tet, dfrA, and blaTEM-1) in 26 isolated subdominant E. coli strains between nearby buffalo and cattle populations, that led us (iv) to hypothesize the role of the human/animal interface in the dissemination of genetic material from human to cattle and toward wildlife. The study of antibiotic resistance dissemination in multihost systems and at anthropized/natural interface is necessary to better understand and mitigate its multiple threats. These results also contribute to attempts aiming at using E. coli as a tool for the identification of pathogen transmission pathway in multihost systems.
Deepest Image of Exploded Star Uncovers Bipolar Jets
NASA Astrophysics Data System (ADS)
A spectacular new image of Cassiopeia A from NASA's Chandra X-ray Observatory released today has nearly 200 times more data than the "First Light" Chandra image of this object made five years ago. The new image reveals clues that the initial explosion caused by the collapse of a massive star was far more complicated than suspected. Chandra Broadband Image of Cassiopeia A Chandra Broadband Image of Cassiopeia A "Although this young supernova remnant has been intensely studied for years, this deep observation is the most detailed ever made of the remains of an exploded star," said Martin Laming of the Naval Research Laboratory in Washington, D.C. Laming is part of a team of scientists led by Una Hwang of the Goddard Space Flight Center in Greenbelt, Maryland. "It is a gold mine of data that astronomers will be panning through for years to come." The one-million-second (about 11.5-day) observation of Cassiopeia A uncovered two large, opposed jet-like structures that extend to about 10 light years from the center of the remnant. Clouds of iron that have remained nearly pure for the approximately 340 years since the explosion were also detected. "The presence of the bipolar jets suggests that jets could be more common in relatively normal supernova explosions than supposed by astronomers," said Hwang. A paper by Hwang, Laming and others on the Cassiopeia A observation will appear in an upcoming issue of The Astrophysical Journal Letters. Chandra Enhanced Silicon Image of Cassiopeia A Chandra Enhanced Silicon Image of Cassiopeia A X-ray spectra show that the jets are rich in silicon atoms and relatively poor in iron atoms. In contrast, fingers of almost pure iron gas extend in a direction nearly perpendicular to the jets. This iron was produced in the central, hottest regions of the star. The high silicon and low iron abundances in the jets indicate that massive, matter-dominated jets were not the immediate cause of the explosion, as these should have carried out large
Eyes wide open: reader and author responsibility in understanding the limits of peer review.
Benson, P J
'Medical science can only flourish in a free society and dies under totalitarian repression.' (1) Peer review post-publication is relatively easy to define: when the world decides the importance of publication. Peer review pre-publication is what the scientific community frequently means when using the term 'peer review'. But what it is it? Few will agree on an exact definition; generally speaking, it refers to an independent, third party scrutiny of a manuscript by scientific experts (called peers) who advise on its suitability for publication. Peer review is expensive; although reviewers are unpaid, the cost in time is enormous and it is slow. There is often little agreement among reviewers about whether an article should be published and peer review can be a lottery. Often referred to as a quality assurance process, there are many examples of when peer review failed. Many will be aware of Woo-Suk Hwang's shocking stem cell research misconduct at Seoul National University. (2) Science famously published two breakthrough articles that were found subsequently to be completely fabricated and this happened in spite of peer review. Science is not unique in making this error. However, love it or hate it, peer review, for the present time at least, is here to stay. In this article, Philippa Benson, Managing Editor of Science Advances (the first open access journal of the American Association for the Advancement of Science), discusses the merits of peer review. Dr Benson has extensive experience in the publishing world and was Executive Director of PJB Consulting, a not-for-profit organisation supporting clients on issues related to converting to full electronic publishing workflows as well as challenges working with international authors and publishers. Her clients included the Public Library of Science journals, the American Society for Nutrition and the de Beaumont Foundation. She recently co-authored a book, What Editors Want: An Author's Guide to Scientific Journal
Resource variability, aggregation and direct density dependence in an open context: the local regulation of an African elephant population.
Chamaillé-Jammes, Simon; Fritz, Hervé; Valeix, Marion; Murindagomo, Felix; Clobert, Jean
1. An emerging perspective in the study of density dependence is the importance of the spatial and temporal heterogeneity of resources. Although this is well understood in temperate ungulates, few studies have been conducted in tropical environments where both food and water are limiting resources. 2. We studied the regulation of one of the world's largest elephant populations in Hwange National Park, Zimbabwe. The study period started in 1986 when the population was released from culling. Using census data we investigated changes in elephant abundance with respect to rainfall and density across the entire park and across waterholes. 3. The population more than doubled since culling stopped. The population increased continuously during the first 6 years, and then fluctuated widely at about 30,000 individuals. Immigration processes must have been involved in the increase of the population size. 4. Population growth rates were negatively related to previous population density by a convex relationship, and negatively related to the ratio of previous population density on annual rainfall by a linear relationship. However, only this latter model (i.e. assuming a fluctuating carrying capacity related to annual rainfall) produced realistic dynamics. Overall, population decreased during dry years when the elephant density was high. 5. During dry years there were fewer waterholes retaining water during the dry season and consequently elephant numbers at waterholes increased, while their aggregation level across waterholes decreased. On the long-run elephant numbers increased only at the less crowded waterholes. 6. We suggest that the interaction between population size and the available foraging range determined by the number of active waterholes during the dry season controls the park population. 7. Our results emphasize the need to understand how key-resource areas cause resource-based aggregation, which ultimately influences the strength of density dependence. More
Characterization of two forms of mouse salivary androgen-binding protein (ABP): implications for evolutionary relationships and ligand-binding function.
Karn, Robert C; Laukaitis, Christina M
Mouse salivary androgen-binding protein (ABP) is a member of the secretoglobin family produced in the submaxillary glands of house mice (Mus musculus). We report the cDNA sequences and amino acid sequences of the beta and gamma subunits of ABP from a mouse cDNA library, identifying the two subunits by their pIs and molecular weights. An anomalously high molecular weight of the alpha subunit is likely due to glycosylation at a single site. A phylogenetic comparison of the three subunits of ABP with the chains of other mammalian secretoglobins shows that ABP is most closely related to mouse lachrymal protein and to the major cat allergen Fel dI. An evaluation of the most conserved residues in ABP and the other secretoglobins, in light of structural data reported by others [Callebaut, I., Poupon, A., Bally, R., Demaret, J.-P., Housset, D., Delettre, J., Hossenlopp, P., and Mornon, J.-P. (2000) Ann. N.Y. Acad. Sci. 923, 90-112; Pattabiraman, N., Matthews, J., Ward, K., Mantile-Selvaggi, G., Miele, L., and Mukherjee, A. (2000) Ann. N.Y. Acad. Sci. 923, 113-127], allows us to draw conclusions about the critical residues important in ligand binding by the two different ABP dimers and to assess the importance of ligand binding in the function of the molecule. In addition to the cDNAs, which represent those of the musculus subspecies of Mus musculus, we also report the coding regions of the beta and gamma subunit cDNAs from two other mouse inbred strains which represent the other two subspecies: M. musculus domesticus and M. musculus castaneus. The high nonsynonymous/synonymous substitution rate ratios (K(a)/K(s)) for both the beta and gamma subunits suggest that these two proteins are evolving under strong directional selection, as has been reported for the alpha subunit [Hwang, J., Hofstetter, J., Bonhomme, F., and Karn, R. (1997) J. Hered. 88, 93-97; Karn, R., and Clements, M. (1999) Biochem. Genet. 37, 187-199].
Traditional Chinese Medicine Induced Liver Injury
Traditional Chinese Medicine (TCM) is popular around the world and encompasses many different practices with particular emphasis on herbal TCM. Using the PubMed database, a literature search was undertaken to assess the extent herbal TCM products exert rare hepatotoxicity. Analysis of reported cases revealed numerous specified herbal TCM products with potential hepatotoxicity. Among these were An Shu Ling, Bai Fang, Bai Xian Pi, Ban Tu Wan, Bo He, Bo Ye Qing Niu Dan, Bofu Tsu Sho San, Boh Gol Zhee, Cang Er Zi, Chai Hu, Chaso, Chi R Yun, Chuan Lian Zi, Ci Wu Jia, Da Chai Hu Tang, Da Huang, Du Huo, Gan Cao, Ge Gen, Ho Shou Wu, Hu Bohe You, Hu Zhang, Huang Qin, Huang Yao Zi, Hwang Geun Cho, Ji Gu Cao, Ji Ji, Ji Xue Cao, Jiguja, Jin Bu Huan, Jue Ming Zi, Kamishoyosan, Kudzu, Lei Gong Teng, Long Dan Xie Gan Tang, Lu Cha, Ma Huang, Mao Guo Tian Jie Cai, Onshido, Polygonum multiflorum, Qian Li Guang, Ren Shen, Sairei To, Shan Chi, Shen Min, Shi Can, Shi Liu Pi, Shou Wu Pian, Tian Hua Fen, White flood, Wu Bei Zi, Xi Shu, Xiao Chai Hu Tang, Yin Chen Hao, Zexie, Zhen Chu Cao, and various unclassified Chinese herbal mixtures. Causality was firmly established for a number of herbal TCM products by a positive reexposure test result, the liver specific scale of CIOMS (Council for International Organizations of Medical Sciences), or both. Otherwise, the quality of case data was mixed, especially regarding analysis of the herb ingredients because of adulteration with synthetic drugs, contamination with heavy metals, and misidentification. In addition, non-herbal TCM elements derived from Agaricus blazei, Agkistrodon, Antelope, Bombyx, Carp, Fish gallbladder, Phellinus, Scolopendra, Scorpio, and Zaocys are also known or potential hepatotoxins. For some patients, the clinical course was severe, with risks for acute liver failure, liver transplantation requirement, and lethality. In conclusion, the use of few herbal TCM products may rarely be associated with hepatotoxicity in some
Resistance Training-Induced Elevations in Muscular Strength in Trained Men Are Maintained After 2 Weeks of Detraining and Not Differentially Affected by Whey Protein Supplementation.
Hwang, Paul S; Andre, Thomas L; McKinley-Barnard, Sarah K; Morales Marroquín, Flor E; Gann, Joshua J; Song, Joon J; Willoughby, Darryn S
Hwang, PS, Andre, TL, McKinley-Barnard, SK, Morales Marroquín, FE, Gann, JJ, Song, JJ, and Willoughby, DS. Resistance training-induced elevations in muscular strength in trained men are maintained after 2 weeks of detraining and not differentially affected by whey protein supplementation. J Strength Cond Res 31(4): 869-881, 2017-Resistance training (RT) with nutritional strategies incorporating whey protein intake postexercise can stimulate muscle protein synthesis and elicit hypertrophy. The early phases of training-induced anabolic responses can be attenuated with longer-term training. It is currently unknown if short-term detraining (DT) can restore these blunted anabolic responses during a subsequent retraining (ReT) period. Twenty resistance-trained men (age 20.95 ± 1.23 years; n = 20) were randomized into one of 2 groups (PRO or CHO; 25 g) in a double-blind manner. Participants followed a 4-day per week RT program (4-week RT; 2-week DT; 4-week ReT) while consuming their respective supplement only on workout days during RT and ReT, but every day during DT. At baseline, 4 weeks after RT (post-RT), 2 weeks after DT (post-2-week DT), and after 4 weeks of ReT after DT (post-ReT), leg press strength (LPS) was assessed and rectus femoris cross-sectional area and lean mass changes were assessed by ultrasonography and dual-energy x-ray absorptiometry, respectively. A factorial 2 × 4 (group by time) analyses of variance with repeated measures were used with a probability level at ≤0.05. LPS was elevated throughout the 10-week training study (p = 0.003) with no decrease in LPS after DT in both groups. Although not statistically significant, both groups retained lean mass after DT. A 2-week period of DT appeared to retain muscular strength in resistance-trained men. Therefore, a short-term period of DT can potentially retain lower-body strength in young resistance-trained men irrespective of supplementing with 25 g of whey protein postexercise.
MicroRNA 339 down-regulates μ-opioid receptor at the post-transcriptional level in response to opioid treatment
Wu, Qifang; Hwang, Cheol Kyu; Zheng, Hui; Wagley, Yadav; Lin, Hong-Yiou; Kim, Do Kyung; Law, Ping-Yee; Loh, Horace H.; Wei, Li-Na
μ-Opioid receptor (MOR) level is directly related to the function of opioid drugs, such as morphine and fentanyl. Although agonist treatment generally does not affect transcription of mor, previous studies suggest that morphine can affect the translation efficiency of MOR transcript via microRNAs (miRNAs). On the basis of miRNA microarray analyses of the hippocampal total RNA isolated from mice chronically treated with μ-opioid agonists, we found a miRNA (miR-339-3p) that was consistently and specifically increased by morphine (2-fold) and by fentanyl (3.8-fold). miR-339-3p bound to the MOR 3′-UTR and specifically suppressed reporter activity. Suppression was blunted by adding miR-339-3p inhibitor or mutating the miR-339-3p target site. In cells endogenously expressing MOR, miR-339-3p inhibited the production of MOR protein by destabilizing MOR mRNA. Up-regulation of miR-339-3p by fentanyl (EC50=0.75 nM) resulted from an increase in primary miRNA transcript. Mapping of the miR-339-3p primary RNA and its promoter revealed that the primary miR-339-3p was embedded in a noncoding 3′-UTR region of an unknown host gene and was coregulated by the host promoter. The identified promoter was activated by opioid agonist treatment (10 nM fentanyl or 10 μM morphine), a specific effect blocked by the opioid antagonist naloxone (10 μM). Taken together, these results suggest that miR-339-3p may serve as a negative feedback modulator of MOR signals by regulating intracellular MOR biosynthesis.—Wu, Q., Hwang, C. K., Zheng, H., Wagley, Y., Lin, H.-Y., Kim, D. K., Law, P.-Y., Loh, H. H., Wei, L.-N. MicroRNA 339 downregulates mu opioid receptor at the post-transcriptional level in response to opioid treatment. PMID:23085997
Quantum-key-distribution protocols without sifting that are resistant to photon-number-splitting attacks
NASA Astrophysics Data System (ADS)
Grazioso, Fabio; Grosshans, Frédéric
We propose a family of sifting-less quantum-key-distribution protocols which use reverse reconciliation, and are based on weak coherent pulses (WCPs) polarized along m different directions. When m=4, the physical part of the protocol is identical to most experimental implementations of BB84 [Bennett and Brassard, in Proceedings of the IEEE International Conference on Computers, Systems, and Signal Processing (IEEE, New York, 1984)] and SARG04 [Scarani, Acín, Ribordy, and Gisin, Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.92.057901 92, 057901 (2004); Acín, Gisin, and Scarani, Phys. Rev. APLRAAN1050-294710.1103/PhysRevA.69.012309 69, 012309 (2004)] protocols and they differ only in classical communications and data processing. We compute their total key rate as a function of the channel transmission T, using general information theoretical arguments, and we show that they have a higher key rate than the more standard protocols, both for fixed and optimized average photon number of the WCPs. When no decoy-state protocols (DSPs) [Hwang, Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.91.057901 91, 057901 (2003); Lo, Ma, and Chen, Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.94.230504 94, 230504 (2005); Wang, Phys. Rev. APLRAAN1050-294710.1103/PhysRevA.72.012322 72, 012322 (2005)] are applied, the scaling of the key rate with transmission is improved from T2 for BB84 to T1+(1)/(m-2). If a DSP is applied, we show how the key rates scale linearly with T, with an improvement of the prefactor by 75.96% for m=4. High values of m allow one to asymptotically approach the key rate obtained with ideal single-photon pulses. The fact that the key rates of these sifting-less protocols are higher compared to those of the aforementioned more standard protocols show that the latter are not optimal, since they do not extract all the available secret keys from the experimental correlations.
Local probe investigation of emergent phenomena in complex oxide heterointerfaces
NASA Astrophysics Data System (ADS)
Huang, Mengchen
Complex oxide heterointerfaces exhibit rich physics as well as many veiled puzzles. LaAlO3/SrTiO3 (LAO/STO) is one of the prototype of such heterointerfaces. In 2004, Ohtomo and Hwang first reported a conducing interface emerged between perovskite oxide insulators LaAlO3 and SrTiO3. Following this seminal discovery, many emergent phenomena like metal-insulator transition, piezoresponse, superconductivity, magnetism, strong spin-orbit coupling and coexistence of superconductivity and magnetism were reported in the fascinating LAO/STO system. However, the origin of the conducting interface is still the subject of intense debate, and the physics behind these emergent phenomena remains a wild space to be explored. My Ph.D. study focused on the emergent phenomena in LAO/STO by using "local probes" -- nanostructures created by conductive atomic force microscope (c-AFM) lithography and the AFM itself. I used piezoresponse force microscope (PFM) to study the electromechanical response in LAO/STO and developed a high-resolution, non-destructive PFM imaging technique to visualize nanostructures at LAO/STO interface. The results indicate that the PFM signal is related to a carrier density mediated interfacial lattice distortion, and surface adsorbates can affect the PFM signal via coupling to the electrons at the interface. I integrated graphene on LAO/STO, created field-effect devices in graphene/LAO/STO and collaborated with Dr. Giriraj Jnawali to investigate the transport properties. The high quality single layer graphene on LAO/STO exhibited the half-integer quantum Hall effect and room temperature weak antilocalization behavior. I performed transport measurements in (110)-oriented LAO/STO to investigate anisotropic quasi one-dimensional superconductivity in nanowires. Based on the results I proposed a plausible explanation related to the Lifshitz transition and anisotropic band structures of nanowires in (110)-oriented LAO/STO. Co-worked with Dr. Keith Brown, I studied
The complete mitochondrial sequence of the"living fossil" Tricholepidion gertschi: structure, phylogenetic implications, and the description of a novel A/T asymmetrical bias
Nardi, F.; Frati, F.; Carapelli, A.; Dallai, R.; Boore, J.
the evolution and differentiation of the most basal hexapod groups, including Tricholepidion. Mitochondrial genomics, that is analysis of various features of the mitochondrial genome such as gene order and the analysis of the concatenated sequence of its genes, has proved to be a very powerful tool for the study of ancient phylogenetic relationships (Boore, 2000; Boore and Brown, 1995; Boore and Brown, 1998; Garcia-Machado et al., 1999; Hwang et al., 2001; Nardi et al., 2001), and its application seems to be appropriate for the problem under study ((Nardi et al., 2001), this study). In addition, complete mitochondrial sequences, with the advent of automatic sequencing tools, are accumulating rapidly, but there is a strong bias towards the better known or economically important groups, while only two sequences have been produced for the more basal, and evolutionarily more intriguing, hexapod orders. The complete sequence of the mitochondrial genome of Tricholepidion gertschi is the second among apterygotans, following the collembolan T.bielanensis (Nardi et al., 2001).
Environmental change on tidal flat induced by anthropogenic effect around west coast of Korean Peninsula
NASA Astrophysics Data System (ADS)
Lee, Yoon-Kyung; Choi, Jong-Kuk; Ryu, Joo-Hyung; Eom, Jinah
Tidal flats are valuable ecosystem by a productive flora and fauna which support large populations of birds, form nursery and feeding areas for coastal fisheries, provide intrinsic values such as aesthetics and education (Costanza et al., 1997; Goodwin et al., 2001). The half of the world's coastal wetlands will submerge during this century in response to sea level rise although salt marsh has a capacity to adjust to sea level rise change. However, tidal flats have been changed because of several coastal construction projects that had not been considered sustainable over the last 30 years in Korean Peninsula. The total area of tidal flats decreased from approximately 2,800 km2 in 1990 to 2,393 km2 in 2005 due to the land reclamations and dredging in South Korea. Many researchers investigated topography, sedimentation changes and local hydrodynamics for this area in the early 1990s. However, they are limited to the temporal and spatial scale because field surveys in the tidal flats are restricted due to the difficulties in accessing. The aim of this study was to examine environmental change in tidal flat in a large scale for long-term based on the remotely sensed data as well as in situ measurements. This study focused on the tidal flat that not only had been affected by reclamations on a large scale such as Ganghwa and Saemangeum but also had been indirectly affected by reclamations such as Hwang-do and Gomso-bay. In this study, changes in morphology and sedimentary facies in tidal flats were estimated. Digital elevation models (DEMs) in early 2000 and 2010 were generated based on the Landsat TM/ETM+ images using a waterline method. Morphological change was estimated based on the differences of DEMs and sedimentary facies was investigated based on the calculation of image-derived PCA coefficient. Results of the morphological change in tidal flats interestingly showed that large amount of areas had been deposited whereas the other areas were eroded. Area with
Preoperative differences of cerebral metabolism relate to the outcome of cochlear implants in congenitally deaf children.
Lee, Hyo Jeong; Kang, Eunjoo; Oh, Seung-Ha; Kang, Hyejin; Lee, Dong Soo; Lee, Myung Chul; Kim, Chong-Sun
In congenitally deaf children, chronological age is generally accepted as a critical factor that affects successful rehabilitation following cochlear implantation (CI). However, a wide variance among patients is known to exist regardless of the age at CI [Sarant, J.Z., Blamey, P.J., Dowell, R.C., Clark, G.M., Gibson, W.P., 2001. Variation in speech perception scores among children with cochlear implants. Ear Hear. 22, 18-28]. In a previous study, we reported that prelingually deaf children in the age range 5-7 years at implantation showed greatest outcome variability [Oh S.H., Kim C.S., Kang E.J., Lee D.S., Lee H.J., Chang S.O., Ahn S.H., Hwang C.H., Park H.J., Koo J.W., 2003. Speech perception after cochlear implantation over a 4-year time period. Acta Otolaryngol. 123, 148-153]. Eleven children who underwent CI between the age of 5 and 7 1/2 years were subdivided into a good (above 65%: GOOD) and a poor (below 45%: POOR) group based on the performance in a speech perception test given 2 years after CI. The preoperative (18)F-FDG-PET (F-18 fluorodeoxyglucose positron emission tomography) images were compared between the two groups in order to examine if regional glucose metabolic difference preexisted before the CI surgery. In the GOOD group, metabolic activity was greater in diverse fronto-parietal regions compared to the POOR group. In the POOR group, the regions related to the ventral visual pathway showed greater metabolic activity relative to the GOOD group. These findings suggest that the deaf children who had developed greater executive and visuospatial functions subserved by the prefrontal and parietal cortices might be successful in auditory language learning after CI. On the contrary, greater dependency on the visual function subserved by the occipito-temporal region due to auditory deprivation may interfere with acquisition of auditory language after CI.
[King Jung-jo's medical philosophy].
Kim, Sun Hyung; Kim, Dal Rae
King Jungjo who introduced the advent of cultural renaissance of Chosun Dynasty as little been known about his work in medicine. With a wide knowledge in medicine, he was the only one among the kings who wrote a book on medicine, called "SueMinMyoJeon". In this paper, his perspective on medicine will be looked into based on "The Annals of the Chosun Dynasty", "Seungjeongwon Ilgi", "Hong Je jun Se", "KukGoBoGam", "Ildkrok", "JeJungShinPyun", "SueMinMyoJeon" etc. King Jungo valued empiricism in the field of medicine. He deepened understandings in medicine while taking care of King Youngjo, the late king. And it led him to author "SueMinMyoJeon" himself, and further ordered the publications of "JeJungShinPyun" "MaGuaHeoiTong". These two books were conducted to include empirical cases of folklore remedy. King Jungjo's medical philosophy can be epitomized in filial piety and realization of people-serving politics, which are the essentials of Confucianism. His filial piety towards the late king, Youngjo and his mother is shown in his devotion when taking care of them. Especially the way he examined the differentiation of diseases and corresponding treatments is well described in "The Annals of the Chosun Dynasty". "JeJungShinPyun" was also published and it came handy for folk villagers in times of medical needs. Later this book influenced "BangYakHaepPyun" by Hwang Do Yeon. King Jungjo emphasized pragmatism in spreading medical knowledges, thus removing the theoretical contents that are related to Taoism, especially the ones on alchemy from "DongEuiBoGam", when publishing "SueMinMyoJeon". Even the excerpts from "SoMun" were taken out, if not practical. King Jungjo, however, discussed the importance of healthy regimen and mentioned himself practicing it from the book "IlDeukLok", which seems to be the only book that derailed from the pragmatistic track. King Jungjo put emphasis on consistency between diagnosis and treatment. In diagnosing, Meridian pulse was taken
Wave Height Attenuation in Heterogeneous Vegetation using Laboratory Observation and Numerical Simulations
NASA Astrophysics Data System (ADS)
Blackmar, P.; Wu, W.; Cox, D. T.
vegetation with an average mean square error of 3.2%. References: Dalrymple, R.A., Kirby, J.T., Hwang, P.A., 1984. Wave refraction due to areas of energy dissipation. J. Waterw., Port Coast. Ocean Eng. 110 (1), 67-79. Kobayashi, N., Raichlen, A.W., Asano, T., 1993. Wave attenuation by vegetation. J. Waterw., Port Coast. Ocean Eng. 199 (1), 30-48.
The egg-sharing model for human therapeutic cloning research: managing donor selection criteria, the proportion of shared oocytes allocated to research, and amount of financial subsidy given to the donor.
Heng, Boon Chin; Tong, Guo Qing; Stojkovic, Miodrag
Recent advances in human therapeutic cloning made by Hwang and colleagues have opened up new avenues of therapy for various human diseases. However, the major bottleneck of this new technology is the severe shortage of human donor oocytes. Egg-sharing in return for subsidized fertility treatment has been suggested as an ethically justifiable and practical solution to overcome the shortage of donor oocytes for therapeutic cloning. Because the utilization of shared oocytes in therapeutic cloning research does not result in any therapeutic benefit to a second party, this would necessitate a different management strategy compared to their use for the assisted conception of infertile women who are unable to produce any oocytes of their own. It is proposed that the pool of prospective egg-sharers in therapeutic cloning research be limited only to younger women (below 30 years of age) with indications for either male partner sub-fertility or tubal blockage. With regards to the proportion of the shared gametes being allocated to research, a threshold number of retrieved oocytes should be set that if not exceeded, would result in the patient being automatically removed from the egg-sharing scheme. Any excess supernumerary oocyte above this threshold number can be contributed to science, and allocation should be done in a randomized manner. Perhaps, a total of 10 retrieved oocytes from the patient may be considered a suitable threshold, since the chances of conception are unlikely to be impaired. With regards to the amount of subsidy being given to the patient, it is suggested that the proportion of financial subsidy should be equal to the proportion of the patient's oocytes being allocated to research. No doubt, the promise of future therapeutic benefit may be offered to the patient instead of financial subsidy. However, this is ethically controversial because therapeutic cloning has not yet been demonstrated to be a viable model of clinical therapy and any promises made to
Material Removal and Specific Energy in the Dynamic Scratching of Gamma Titanium Aluminides
Wang, Hong; Lin, Hua-Tay; Wereszczak, Andrew A
Mechanical responses of three gamma titanium aluminides (TiAls) (denoted as Alloy A, Alloy B and Alloy C) subjected to dynamic scratching were studied by using a single-grit pendulum (rotating) scratch tester. The maximum depth of groove was ~ 0.07 mm, and the scratch velocity used was ~ 1.0 m/s. Normal and tangential forces were monitored. The material removal mechanisms were examined using a scanning electron microscope (SEM) and the scratches were measured by using a laser profilometer. The mechanical properties of the tested TiAls were characterized by the instantaneous specific energy, scratch resistance and scratch hardness as related to the depth of groove. Extensive thermal softening was observed in the dynamic scratch of the tested TiAls, which facilitated both the detachments of developing chips and the pile-ups of materials on side ridges. Sizable fractures were observed in the transverse direction on the tested TiAls; these fractures tended to participate in the chip formation, depending on the microstructure of the TiAl and the size of the scratch groove. Specific energy and scratch hardness are depth-dependent to various degrees for the tested TiAls. The materiel removal might be subjected to different mechanisms, but the overall response of materials can be effectively characterized by the HEM (Hwang, Evans and Malkin) model and the PSR (proportional specimen resistance) model. The obtained depth-independent specific energy and scratch hardness can be used to screen the candidate materials for the specific purpose depending on whether the application is scratch-dominant or impact-dominant. Among the three tested TiAls, the TiAl with larger colony or grain size exhibits a stronger capability of energy dissipation in the material loss or material removal (higher depth-independent specific energy), while the TiAl with smaller colony size show a higher resistance against the indentation (higher depth-independent scratch hardness). The observations and
Material Removal and Specific Energy in the Dynamic Scratching of Gamma Titanium Aluminides
Wang, H.; Lin, H.-T.; Wereszczak, A.A.
Mechanical responses of three gamma titanium aluminides (TiAls) (denoted as Alloy A, Alloy B and Alloy C) subjected to dynamic scratching were studied by using a single-grit pendulum (rotating) scratch tester. The maximum depth of groove was {approx} 0.07 mm, and the scratch velocity was {approx} 1.0 m/s. Normal and tangential forces were monitored. The material removal mechanisms were examined using a scanning electron microscope (SEM) and the scratches were measured by using a laser profilometer. The mechanical properties of the tested TiAls were characterized by the instantaneous specific energy, scratch resistance and scratch hardness as related to the groove depth. Extensive thermal softening was observed in the dynamic scratch test of the TiAls, which facilitated both the detachment of developing chips and pile-up of material on side ridges. Sizable fractures were observed in the transverse direction in the tested TiAls; these fractures tended to participate in the chip formation, depending on the microstructure of the TiAl and the size of the scratch groove. Specific energy and scratch hardness are depth-dependent to various degrees for the TiAls tested. The material removal might be subjected to different mechanisms, but the overall material response can be effectively characterized by the HEM (Hwang, Evans and Malkin) model and the PSR (proportional specimen resistance) model. The depth-independent specific energy and scratch hardness can be used to screen candidate materials for the applications that are scratch-dominated versus impact-dominated. Among the three tested TiAls, the TiAl with larger colony or grain size exhibits a stronger capability of energy dissipation during material removal (higher depth-independent specific energy), while the TiAl with smaller colony size shows a higher resistance to indentation (higher depth-independent scratch hardness). The observations and conclusions in this study can serve as a base line for the further
Calmodulin activation of an endoplasmic reticulum-located calcium pump involves an interaction with the N-terminal autoinhibitory domain
NASA Technical Reports Server (NTRS)
Hwang, I.; Harper, J. F.; Liang, F.; Sze, H.
To investigate how calmodulin regulates a unique subfamily of Ca(2+) pumps found in plants, we examined the kinetic properties of isoform ACA2 identified in Arabidopsis. A recombinant ACA2 was expressed in a yeast K616 mutant deficient in two endogenous Ca(2+) pumps. Orthovanadate-sensitive (45)Ca(2+) transport into vesicles isolated from transformants demonstrated that ACA2 is a Ca(2+) pump. Ca(2+) pumping by the full-length protein (ACA2-1) was 4- to 10-fold lower than that of the N-terminal truncated ACA2-2 (Delta2-80), indicating that the N-terminal domain normally acts to inhibit the pump. An inhibitory sequence (IC(50) = 4 microM) was localized to a region within valine-20 to leucine-44, because a peptide corresponding to this sequence lowered the V(max) and increased the K(m) for Ca(2+) of the constitutively active ACA2-2 to values comparable to the full-length pump. The peptide also blocked the activity (IC(50) = 7 microM) of a Ca(2+) pump (AtECA1) belonging to a second family of Ca(2+) pumps. This inhibitory sequence appears to overlap with a calmodulin-binding site in ACA2, previously mapped between aspartate-19 and arginine-36 (J.F. Harper, B. Hong, I. Hwang, H.Q. Guo, R. Stoddard, J.F. Huang, M.G. Palmgren, H. Sze inverted question mark1998 J Biol Chem 273: 1099-1106). These results support a model in which the pump is kept "unactivated" by an intramolecular interaction between an autoinhibitory sequence located between residues 20 and 44 and a site in the Ca(2+) pump core that is highly conserved between different Ca(2+) pump families. Results further support a model in which activation occurs as a result of Ca(2+)-induced binding of calmodulin to a site overlapping or immediately adjacent to the autoinhibitory sequence.
Water flow in fractured rock masses: numerical modeling for tunnel inflow assessment
NASA Astrophysics Data System (ADS)
Gattinoni, P.; Scesi, L.; Terrana, S.
Water circulation in rocks represents a very important element to solve many problems linked with civil, environmental and mining engineering. In particular, the interaction of tunnelling with groundwater has become a very relevant problem not only due to the need to safeguard water resources from impoverishment and from the pollution risk, but also to guarantee the safety of workers and to assure the efficiency of the tunnel drainage systems. The evaluation of the hydrogeological risk linked to the underground excavation is very complex, either for the large number of variables involved or for the lack of data available during the planning stage. The study is aimed to quantify the influence of some geo-structural parameters (i.e. discontinuities dip and dip direction) on the tunnel drainage process, comparing the traditional analytical method to the modeling approach, with specific reference to the case of anisotropic rock masses. To forecast the tunnel inflows, a few Authors suggest analytic formulations (Goodman et al., 1965; Knutsson et al., 1996; Ribacchi et al., 2002; Park et al., 2008; Perrochet et al., 2007; Cesano et al., 2003; Hwang et al., 2007), valid for infinite, homogeneous and isotropic aquifer, in which the permeability value is given as a modulus of equivalent hydraulic conductivity Keq. On the contrary, in discontinuous rock masses the water flow is strongly controlled by joints orientation, by their hydraulic characteristics and by rocks fracturing conditions. The analytic equations found in the technical literature could be very useful, but often they don't reflect the real phenomena of the tunnel inflow in rock masses. Actually, these equations are based on the hypothesis of homogeneous aquifer, and then they don't give good agreement for an heterogeneous fractured medium. In this latter case, the numerical modelling could provide the best results, but only with a detailed conceptual model of the water circulation, high costs and long
Exclusive Reactions at High Momentum Transfer
NASA Astrophysics Data System (ADS)
Radyushkin, Anatoly; Stoler, Paul
effects from initial and final state interactions / S. J. Brodsky -- Parton distributions and spin-orbital correlations / F. Yuan -- Transverse momentum dependences of distribution and fragmentation functions / D. S. Hwang and D. S. Kim -- Flavor dependence of the Boer-Mulders function and its influence on Azimuthal and single-spin asymmetries in semi-inclusive DIS / L. P. Gamberg, G. R. Goldstein and M. Schlegel -- Symmetric spin-dependent structure function in deep inelastic processes / D. S. Hwang, J. H. Kim and S. Kim -- HERMES recoil detector / R. Perez-Benito -- Inner calorimeter in CLAS/DVCS experiment / R. Niyazov -- Frozen-spin HD as a possible target for electro-production experiments / A. M. Sandorfi et al.
2-D Hartee-Fock-Bogoliubov Calculations For Exotic Deformed Nuclei
NASA Astrophysics Data System (ADS)
Blazkiewicz, Artur; Oberacker, Volker E.; Umar, Sait A.; Teran, Edgar
We solve the Hartree-Fock-Bogoliubov (HFB) equations in coordinate space; the computational method has been specifically designed to study ground state properties of nuclei near the neutron and proton drip lines teref1. The unique feature of our code is that it takes into account the strong coupling to high-energy continuum states, up to an equivalent single-particle energy of 60 MeV or higher. We solve the HFB equations for deformed, axially symmetric even-even nuclei in coordinate space on a 2-D lattice with Basis-Spline methods. For the p-h channel, the Skyrme (SLy4) effective N-N interaction is utilized, and for the p-p and h-h channel we use a delta interaction. Results teref2,ref3 are presented for binding energies, deformations, normal densities and pairing densities, Fermi levels, and pairing gaps. In particular, we calculate the properties of two light isotope chains up to the two-neutron dripline: oxygen (^22-28O) and sulfur (^40-52S). For some of the sulfur isotopes we found the "shape coexistence" what was also confirmed by RMF calculations of P. Ring and G.A. Lalazissis teref4. Furthermore, we study the strongly deformed heavy systems zirconium (^102,104Zr), cerium (^152Ce), and samarium (^158Sm).We are also planning to study other isotopes by running our new parallel MPI version of HFB code. Comparison with relativistic mean field theory and with experimental data is given whenever available. This work has been supported by the U.S. Department of Energy under grant No. DE-FG02-96ER40963 with Vanderbilt University. The numerical calculations were carried out on the IBM-RS/6000 SP supercomputer at NERSC in Berkeley and on our local "Beowulf" Vampire computer at Vanderbilt University. 99 ref1 Axially Symmetric Hartee-Fock-Bogoliubov calculations for nuclei near the drip lines,E. Teran, V.E. Oberacker and A.S. Umar, Phys. Rev. C 67, (June 2003) ref2 Half lives of isomeric states from SF of ^252Cf and large deformations in ^104Zr and ^158Sm, J.K. Hwang, A
Hawaii Beach Monitoring Program: Beach Profile Data
Gibbs, Ann E.; Richmond, Bruce M.; Fletcher, Charles H.; Hillman, Kindra P.
Coastal erosion is widespread and locally severe in Hawaii and other low-latitude areas. Typical erosion rates in Hawaii are in the range of 15 to 30 cm/yr (0.5 to 1 ft/yr; Hwang, 1981; Sea Engineering, Inc., 1988; Makai Ocean Engineering, Inc. and Sea Engineering, Inc.,1991). Recent studies on Oahu (Fletcher et al., 1997; Coyne et al., 1996) have shown that nearly 24%, or 27.5 km (17.1 mi) of an original 115 km (71.6 mi) of sandy shoreline (1940's) has been either significantly narrowed (17.2 km; 10.7 mi) or lost (10.3 km; 6.4 mi). Nearly one-quarter of the islands' beaches have been significantly degraded over the last half-century and all shorelines have been affected to some degree. Oahu shorelines are by far the most studied, however, beach loss has been identified on the other islands as well, with nearly 13 km (8 mi) of beach likely lost due to shoreline hardening on Maui (Makai Engineering, Inc. and Sea Engineering, Inc., 1991). Causes of coastal erosion and beach loss in Hawaii are numerous but, unfortunately, poorly understood and rarely quantified. Construction of shoreline protection structures limits coastal land loss, but does not alleviate beach loss and may actually accelerate the problem by prohibiting sediment deposition in front of the structures. Other factors contributing to beach loss include: a) reduced sediment supply; b) large storms; and, c) sea-level rise. Reduction in sand supply, either from landward or seaward (primarily reef) sources, can have a myriad of causes. Obvious causes such as beach sand mining and emplacement of structures that interrupt natural sediment transport pathways or prevent access to backbeach sand deposits, remove sediment from the active littoral system. More complex issues of sediment supply can be related to reef health and carbonate production which, in turn, may be linked to changes in water quality. Second, the accumulated effect of large storms is to transport sediment beyond the littoral system. Third
Mapping the entangled ontology of science teachers' lived experience
NASA Astrophysics Data System (ADS)
Daugbjerg, Peer S.; de Freitas, Elizabeth; Valero, Paola
In this paper we investigate how the bodily activity of teaching, along with the embodied aspect of lived experience, relates to science teachers' ways of dealing with bodies as living organisms which are both the subject matter as well as the site or vehicle of learning. More precisely, the following questions are pursued: (1) In what ways do primary science teachers refer to the lived and living body in teaching and learning? (2) In what ways do primary science teachers tap into past experiences in which the body figured prominently in order to teach students about living organisms? We draw on the relational ontology and intra-action of Karen Barad (J Women Cult Soc 28(3): 801, 2003) as she argues for a "relational ontology" that sees a relation as a dynamic flowing entanglement of a matter and meaning. We combine this with the materialist phenomenological studies of embodiment by SungWon Hwang and Wolff-Michael Roth (Scientific and mathematical bodies, Sense Publishers, Rotterdam, 2011), as they address how the teachers and students are present in the classroom with/in their "living and lived bodies". Our aim is to use theoretical insights from these two different but complementary approaches to map the embodiment of teachers' experiences and actions. We build our understanding of experience on the work of John Dewey (Experience and education, Simon & Schuster, New York, 1938) and also Jean Clandinin and Michael Connelly (Handbook of qualitative research, Sage Publications, California, 2000), leading us to propose three dimensions: settings, relations and continuity. This means that bodies and settings are mutually entailed in the present relation, and furthermore that the past as well as the present of these bodies and settings—their continuity—is also part of the present relation. We analyse the entanglement of lived experience and embodied teaching using these three proposed dimensions of experience. Analysing interviews and observations of three Danish
American Academy of Sleep Medicine (AASM) Position Paper for the Use of Telemedicine for the Diagnosis and Treatment of Sleep Disorders
Singh, Jaspal; Badr, M. Safwan; Diebert, Wendy; Epstein, Lawrence; Hwang, Dennis; Karres, Valerie; Khosla, Seema; Mims, K. Nicole; Shamim-Uzzaman, Afifa; Kirsch, Douglas; Heald, Jonathan L.; McCann, Kathleen
providers, and other members of the healthcare team aim to improve the value of healthcare delivery in a coordinated fashion.Appropriate technical standards should be upheld throughout the telemedicine care delivery process, at both the originating and distant sites, and specifically meet the standards set forth by the Health Insurance Portability and Accountability Act (HIPAA).Methods that aim to improve the utility of telemedicine exist and should be explored, including the utilization of patient presenters, local resources and providers, adjunct testing, and add-on technologies.Quality Assurance processes should be in place for telemedicine care delivery models that aim to capture process measures, patient outcomes, and patient/provider experiences with the model(s) employed.Time for data management, quality processes, and other aspects of care delivery related to telemedicine encounters should be recognized in value-based care delivery models.The use of telemedicine services and its equipment should adhere to strict professional and ethical standards so as not to violate the intent of the telemedicine interaction while aiming to improve overall patient access, quality, and/or value of care.When billing for telemedicine services, it is recommended that patients, providers, and others rendering services understand payor reimbursements, and that there be financial transparency throughout the process.Telemedicine utilization for sleep medicine is likely to rapidly expand, as are broader telehealth applications in general; further research into the impact and outcomes of these are needed. This document serves as a resource by defining issues and terminology and explaining recommendations. However, it is not intended to supersede regulatory or credentialing recommendations and guidelines. It is intended to support and be consistent with professional and ethical standards of the profession. Citation: Singh J, Badr MS, Diebert W, Epstein L, Hwang D, Karres V, Khosla S, Mims KN
Inference of directed climate networks: role of instability of causality estimation methods
NASA Astrophysics Data System (ADS)
Hlinka, Jaroslav; Hartman, David; Vejmelka, Martin; Paluš, Milan
weights in the networks is ~ 0.6. The networks constructed using nonlinear measures were in general less stable both in real data and stationarized surrogates. Interestingly, when the nonlinear method parameters are optimized with respect to temporal stability of the networks, the networks seem to converge close to those detected by linear Granger causality. This provides further evidence for the hypothesis of overall sparsity and weakness of nonlinear coupling in climate networks on this spatial and temporal scale [3] and sufficient support for the use of linear methods in this context, unless specific clearly detectable nonlinear phenomena are targeted. Acknowledgement: This study is supported by the Czech Science Foundation, Project No. P103/11/J068. [1] Boccaletti, S.; Latora, V.; Moreno, Y.; Chavez, M. & Hwang, D. U.: Complex networks: Structure and dynamics, Physics Reports, 2006, 424, 175-308 [2] Barnett, L.; Barrett, A. B. & Seth, A. K.: Granger Causality and Transfer Entropy Are Equivalent for Gaussian Variables, Physical Review Letters, 2009, 103, 238701 [3] Hlinka, J.; Hartman, D.; Vejmelka, M.; Novotná, D.; Paluš, M.: Non-linear dependence and teleconnections in climate data: sources, relevance, nonstationarity, submitted preprint (http://arxiv.org/abs/1211.6688)
A novel HVSR approach on structural heath monitoring for structural vulnerability assesement
NASA Astrophysics Data System (ADS)
Pentaris, Fragkiskos P.; Papadopoulos, Ilias
of Education of Greece and the European Union in the framework of the project entitled «Interdisciplinary Multi-Scale Research of Earthquake Physics and Seismotectonics at the front of the Hellenic Arc (IMPACT-ARC) ». References [1] F. P. Pentaris, J. Stonham, and J. P. Makris, "A review of the state-of-the-art of wireless SHM systems and an experimental set-up towards an improved design," presented at the EUROCON, 2013 IEEE, Zagreb, 2013. [2] R. Ditommaso, M. Mucciarelli, S. Parolai, and M. Picozzi, "Monitoring the structural dynamic response of a masonry tower: Comparing classical and time-frequency analyses," Bulletin of Earthquake Engineering, vol. 10, pp. 1221-1235, 2012. [3] Sungkono, D. D. Warnana, Triwulan, and W. Utama, "Evaluation of Buildings Strength from Microtremor Analyses " International Journal of Civil & Environmental Engineering IJCEE-IJENS, vol. 11, 2011. [4] L.-L. Hong and W.-L. Hwang, "Empirical formula for fundamental vibration periods of reinforced concrete buildings in Taiwan," Earthquake Engineering & Structural Dynamics, vol. 29, pp. 327-337, 2000.
Brodsky, S
Measurements from HERMES, SMC, and Jlab show a significant single-spin asymmetry in semi-inclusive pion leptoproduction {gamma}*(q)p {yields} {pi}X when the proton is polarized normal to the photon-to-pion production plane. Hwang, Schmidt, and I [1] have shown that final-state interactions from gluon exchange between the outgoing quark and the target spectator system lead to such single-spin asymmetries at leading twist in perturbative QCD; i.e., the rescattering corrections are not power-law suppressed at large photon virtuality Q{sup 2} at fixed x{sub bj}. The existence of such single-spin asymmetries (the Sivers effect) requires a phase difference between two amplitudes coupling the proton target with J{sub p}{sup z} = {+-} 1/2 to the same final-state, the same amplitudes which are necessary to produce a nonzero proton anomalous magnetic moment. The single-spin asymmetry which arises from such final-state interactions is in addition to the Collins effect which measures the transversity distribution {delta}q(x, Q). The Sivers effect also leads to a leading-twist target single-spin asymmetry for jet production in electroproduction where the thrust axis is used to define the production plane. More generally, Hoyer, Marchal, Peigne, Sannino, and I [2] have shown that one cannot neglect the interactions which occur between the times of the currents in the current correlator even in light-cone gauge. For example, the final-state interactions lead to the Bjorken-scaling diffractive component {gamma}*p {yields} pX of deep inelastic scattering. Since the gluons exchanged in the final state carry negligible k{sup +}, the Pomeron structure function closely resembles that of the primary gluon. The diffractive scattering of the fast outgoing quarks on spectators in the target in turn causes shadowing in the DIS cross section. These effects highlight the unexpected importance of final- and initial-state interactions in QCD observables, they lead to leading-twist single
Coincident Retrieval of Sea Surface Salinity from the Northern Gulf of Mexico Using SMOS and STARRS During the 2011 COSSAR Airborne Campaign.
NASA Astrophysics Data System (ADS)
Burrage, D. M.; Wesson, J. C.; Wang, D. W.; Hwang, P. A.; Howden, S. D.
surveys were conducted over an oceanographic research vessel that was collecting in situ temperature and salinity data, and star-shaped patterns were flown over NOAA buoys recording in situ winds, waves and temperatures. The coincident ship, STARRS, SMOS and NOAA buoy data are being used to assess the performance of alternative roughness correction models for the SSS retrievals, including one based on Hwang's new wind-wave spectrum. Analysis of data from the STARRS L-band radiometer reveals large freshwater plumes from the Mississippi and Atchafalaya Rivers, separated from offshore regions with quite subtle SSS variations by sharp salinity and color fronts (see also Wesson, Burrage, Wang and Howden, "Sea Surface Salinity and Ocean Color Observations in the Northern Gulf of Mexico Using SMOS and STARRS"). The salinity fronts exhibited SSS contrasts of 7-15 psu over 10 km spans. The buoy data and aerial photographs show the low wind speeds produced only weak to moderate wind-wave development, so that roughness influence on SSS retrieval was modest. This situation will be contrasted with observations from the Virginia Offshore (VIRGO) STARRS airborne campaign, to be conducted during wintertime off Chesapeake Bay and across the Gulf Stream in Feb., 2012. This will also overfly NOAA buoys and underfly SMOS.
Constitutive relations for steady, dense granular flows
NASA Astrophysics Data System (ADS)
Vescovi, D.; Berzi, D.; di Prisco, C. G.
-instantaneous collisions [4]. We have shown that the present theory is capable of reproducing, qualitatively and quantitatively, the numerical simulations on disks [2] and the experiments on incline flows of glass spere [9]. [1] C. S. Campbell, Annual Review of Fluid Mechanics 22, 57 (1990) [2] F. da Cruz, S. Emam, M. Prochnow, J. Roux, and F. Chevoir, Physical Review E 72, 021309 (2005) [3] I. Goldhirsch, Annual Review of Fluid Mechanics 35, 267 (2003). [4] H. Hwang and K. Hutter, Continuum Mechanics and Thermodynamics 7, 357 (1995) [5] J. T. Jenkins, Granular Matter 10, 47 (2007) [6] J. T. Jenkins, Physics of Fluids 18, 103307 (2006) [7] J. T. Jenkins and M. W. Richman, Archive for Rational Mechanics and Analysis 87, 355 (1985) [8] D. Muir Wood, Geotechnical modelling (Spon Press, New York, 2004) [9] O. Pouliquen, Physics of Fluids 11, 542 (1999) [10] A. N. Schofield and C. P. Wroth, Critical state soil mechanics (McGraw-Hill, London, U.K., 1968) [11] C. Song, P. Wang, and H. A. Makse, Nature 453, 629 (2008)
News from Online: A Spectrum of Color
NASA Astrophysics Data System (ADS)
Sweeney Judd, Carolyn
://acept.la.asu.edu/PiN/act/activities.shtml, plan to spend some time, for it is wonderful. Another link from the About Rainbows tutorial goes to an experiment that is suitable for older students, Circles of Light--The Mathematics of Rainbows at http://www.geom.umn.edu/education/calc-init/rainbow/. Frederick J. Wicklin and Paul Edelman of the University of Minnesota note that this comprehensive lab is based on a module developed by Steven Janke. Go back to About Rainbows to link to a Java applet, allowing you to change the incident angle and color of light striking a water droplet. This great teaching device is from Fu-Kwun Hwang of the National Taiwan Normal University at http://science.kongju.ac.kr/phys/shin/experiment/ntnujava /Rainbow/rainbow.html. And while you are here in this site (choose English or Chinese), look at the more than 30 Java applets created by F.-K. Hwang at http://science.kongju.ac.kr/phys/shin/experiment/ntnujava/index.html. The interactive applet on Shadow/Image and Color is great fun, (http://science.kongju.ac.kr/phys/shin/experiment/ntnujava/shadow /shadow.html). From mixing colors, we can go to Thomas Chasteen's fine work at http://www.shsu.edu/~chm_tgc/sounds/sound.html for an animation (and movie also) of how to separate colors using a tuneable monochromator ( http://www.shsu.edu/~chemistry/monochromator/mono.gif). This colorful graphic, showing incoming parallel white light, is clipped from that monochromator animation. While you are here at this site at Sam Houston State University, look at the other great animations and movies, including a movie showing solution-phase chemiluminescence at http://www.shsu.edu/~chm_tgc/chemilumdir/movie.html. So now that we have explored the breaking down of light into its component colors, we need to also look at another process--polarizing light. Let's go to Science Media's comprehensive site ( http://www.scimedia.com/index.html#scimedia) to examine polarized light ( http://www.scimedia.com/chem-ed/spec/molec/polarim.htm). Of course, most sunglasses
EDITORIAL: Synaptic electronics Synaptic electronics
NASA Astrophysics Data System (ADS)
Demming, Anna; Gimzewski, James K.; Vuillaume, Dominique
integrated memristors Nanotechnology 24 384011 [7] Timm C and Di Ventra M 2013 Molecular neuron based on the Franck-Condon blockade Nanotechnology 24 384001 [8] Sillin H O, Aguilera R, Shieh H-H, Avizienis A V, Aono M, Stieg A Z and Gimzewski J K 2013 A theoretical and experimental study of neuromorphic atomic switch networks for reservoir computing Nanotechnology 24 384004 [9] Linn E, Menzel S, Ferch S and Waser R 2013 Compact modeling of CRS devices based on ECM cells for memory, logic and neuromorphic applications Nanotechnology 24 384008 [10] Konkoli Z and Wendin G 2013 A generic simulator for large networks of memristive elements Nanotechnology 24 384007 [11] Gacem K, Retrouvey J-M, Chabi D, Filoramo A, Zhao W, Klein J-O and Derycke V 2013 Neuromorphic function learning with carbon nanotube-based synapses Nanotechnology 24 384013 [12] Lim H, Kim I, Kim J-S, Hwang C S and Jeong D S 2013 Short-term memory of TiO2-based electrochemical capacitors: empirical analysis with adoption of a sliding threshold Nanotechnology 24 384005 [13] Park S, Noh J, Choo M-L, Sheri A M, Chang M, Kim Y-B, Kim C J, Jeon M, Lee B-G, Lee B H and Hwang H 2013 Nanoscale RRAM-based synaptic electronics: toward a neuromorphic computing device Nanotechnology 24 384009 [14] Yang R, Terabe K, Yao Y, Tsuruoka T, Hasegawa T, Gimzewski J K and Aono M 2013 Synaptic plasticity and memory functions achieved in WO3-x-based nanoionics device by using principle of atomic switch operation Nanotechnology 24 384002 [15] Ambrogio S, Balatti S, Nardi F, Facchinetti S and Ielmini D 2013 Spike-timing dependent plasticity in a transistor-selected resistive switching memory Nanotechnology 24 384012 [16] Indiveria G, Linares-Barranco B, Legenstein R, Deligeorgis G and Prodromakise T 2013 Integration of nanoscale memristor synapses in neuromorphic computing architectures Nanotechnology 24 384010 [17] Hino T, Hasegawa T, Tanaka H, Tsuruoka T, Terabe K, Ogawa T and Aono M 2013 Volatile and nonvolatile selective switching of
Fission and Properties of Neutron-Rich Nuclei
NASA Astrophysics Data System (ADS)
Hamilton, Joseph H.; Ramayya, A. V.; Carter, H. K.
spontaneous fission of [symbol]Cf / A. V. Daniel ... [et al.]. Magnetic moment measurements in a radioactive beam environment / N. Benczer-Koller and G. Kumbartzki. g-Factor measurements of picosecond states: opportunities and limitations of the recoil-in-vacuum method / N. J. Stone ... [et al.]. Precision mass measurements and trap-assisted spectroscopy of fission products from Ni to Pd / A. Jokinen -- Fission II. Fission research at IRMM / F.-J. Hambsch. Fission yield measurements at the IGISOL facility with JYFLTRAP / H. Penttilä ... [et al.]. Fission of radioactive beams and dissipation in nuclear matter / A. Heinz (for the CHARMS collaboration). Fission of [symbol]U at 80 MeVlu and search for new neutron-rich isotopes / C.M. Folden, III ... [et al.]. Measurement of the average energy and multiplicity of prompt-fission neutrons and gamma rays from [symbol], [symbol], and [symbol] for incident neutron energies of 1 to 200 MeV / R. C. Haight ... [et al.]. Fission measurements with DANCE / M. Jandel ... [et al.]. Measured and calculated neutron-induced fission cross sections of [symbol]Pu / F. Tovesson and T. S. Hill. The fission barrier landscape / L. Phair and L. G. Moretto. Fast neutron-induced fission of some actinides and sub-actinides / A. B. Lautev ... [et al.] -- Fission III/Nuclear structure III. Complex structure in even-odd staggering of fission fragment yields / M. Caamāno and F. Rejmund. The surrogate method: past, present and future / S. R. Lesher ... [et al]. Effects of nuclear incompressibility on heavy-ion fusion / H. Esbensen and Ş. Mişicu. High spin states in [symbol]Pm / A. Dhal ... [et al]. Structure of [symbol]Sm, spherical vibrator versus softly deformed rotor / J. B. Gupta -- Astrophysics. Measuring the astrophysical S-factor in plasmas / A. Bonasera ... [et al.]. Is there shell quenching or shape coexistence in Cd isotopes near N = 82? / J. K. Hwang, A. V. Ramayya and J. H. Hamilton. Spectroscopy of neutron-rich palladium and cadmium isostopes
Improving community ambulation after hip fracture: protocol for a randomised, controlled trial
Orwig, D; Mangione, KK; Baumgarten, M; Terrin, M; Fortinsky, R; Kenny, AM; Gruber-Baldini, AL; Beamer, B; Tosteson, ANA; Shardell, M; Magder, L; Binder, E; Koval, K; Resnick, B; Craik, RL; Magaziner, J
, or if the participant has low potential to benefit from the interventions. Interventions Participants are randomly assigned to one of two multi-component treatment groups: PUSH or PULSE. PUSH is based on aerobic conditioning, specificity of training, and muscle overload, while PULSE includes transcutaneous electrical nerve stimulation, flexibility activities, and active range of motion exercises. Participants in both groups receive 32 visits in their place of residence from a study physiotherapist (two visits per week on non-consecutive days for 16 weeks). The physiotherapists' adherence to the treatment protocol, and the participants' receipt of the prescribed activities are assessed. Participants also receive counselling from a registered dietician and vitamin D, calcium and multivitamin supplements during the 16-week intervention period. Measurements The primary outcome (community ambulation) is the ability to walk 300 m or more in 6 minutes, as assessed by the 6-minute walk test, at 16 weeks after randomisation. Other measures at 16 and 40 weeks include cost-effectiveness, endurance, dynamic balance, walking speed, quadriceps strength, lower extremity function, activities of daily living, balance confidence, quality of life, physical activity, depressive symptoms, increase of ≥ 50 m in distance walked in 6 minutes, cognitive status, and nutritional status. Analysis Analyses for all aims will be performed according to the intention-to-treat paradigm. Except for testing of the primary hypothesis, all statistical tests will be two-sided and not adjusted for multiple comparisons. The test of the primary hypothesis (comparing groups on the proportion who are community ambulators at 16 weeks after randomisation) will be based on a one-sided 0.025-level hypothesis test using a procedure consisting of four interim analyses and one final analysis with critical values chosen by a Hwang-Shih-Decani alpha-spending function. Analyses will be performed to test group
EDITORIAL: Message from the Editor Message from the Editor
NASA Astrophysics Data System (ADS)
Thomas, Paul
As usual, being an even year, the 23rd IAEA Fusion Energy Conference took place at Daejeon, Korea. The event was notable not just for the quality of the presentations but also for the spectacular opening ceremony, in the presence of the Prime Minister, Kim Hwang-sik. The Prime Minister affirmed the importance of research into fusion energy research and pledged support for ITER. Such political visibility is good news, of course, but it brings with it the obligation to perform. Fortunately, good performance was much in evidence in the papers presented at the conference, of which a significant proportion contain 'ITER' in the title. Given this importance of ITER and the undertaking by the Nuclear Fusion journal to publish papers associated with Fusion Energy Conference presentations, the Nuclear Fusion Editorial Board has decided to adopt a simplified journal scope that encompasses technology papers more naturally. The scope is available from http://iopscience.iop.org/0029-5515/page/Journal%20information but is reproduced here for clarity: Nuclear Fusion publishes articles making significant advances to the field of controlled thermonuclear fusion. The journal scope includes: the production, heating and confinement of high temperature plasmas; the physical properties of such plasmas; the experimental or theoretical methods of exploring or explaining them; fusion reactor physics; reactor concepts; fusion technologies. The key to scope acceptability is now '....significant advances....' rather than any particular area of controlled thermonuclear fusion research. It is hoped that this will make scope decisions easier for the Nuclear Fusion office, the referees and the Editor.The Nuclear Fusion journal has continued to make an important contribution to the research programme and has maintained its position as the leading journal in the field. This is underlined by the fact that Nuclear Fusion has received an impact factor of 4.270, as listed in ISI's 2009 Science Citation
EDITORIAL: Flexible OLEDs and organic electronics Flexible OLEDs and organic electronics
NASA Astrophysics Data System (ADS)
Kim, Jang-Joo; Han, Min-Koo; Noh, Yong-Young
-voltage, solution-processed organic field-effect transistors M Caironi, Y-Y Noh and H Sirringhaus Nonvolatile memory thin-film transistors using an organic ferroelectric gate insulator and an oxide semiconducting channel Sung-Min Yoon, Shinhyuk Yang, Chun-Won Byun, Soon-Won Jung, Min-Ki Ryu, Sang-Hee Ko Park, ByeongHoon Kim, Himchan Oh, Chi-Sun Hwang and Byoung-Gon Yu The status and perspectives of metal oxide thin-film transistors for active matrix flexible displays Jae Kyeong Jeong Vertical phase segregation of hybrid poly(3-hexylthiophene) and fullerene derivative composites controlled via velocity of solvent drying Tao Song, Zhongwei Wu, Yingfen Tu, Yizheng Jin and Baoquan Sun Variations of cell performance in ITO-free organic solar cells with increasing cell areas Jun-Seok Yeo, Jin-Mun Yun, Seok-Soon Kim, Dong-Yu Kim, Junkyung Kim and Seok-In Na
Surface nanobubbles and micropancakes
NASA Astrophysics Data System (ADS)
Seddon, James R. T.
, Ziaul Haque Ansari and Jianguo Mi The effect of PeakForce tapping mode AFM imaging on the apparent shape of surface nanobubblesWiktoria Walczyk, Peter M Schön and Holger Schönherr Coarse-grained modelling of surface nanobubblesPatrick Grosfils Understanding the stability of surface nanobubblesShuo Wang, Minghuan Liu and Yaming Dong Hydrogen nanobubble at normal hydrogen electrodeS Nakabayashi, R Shinozaki, Y Senda and H Y Yoshikawa Particle tracking around surface nanobubblesErik Dietrich, Harold J W Zandvliet, Detlef Lohse and James R T Seddon Imaging surface nanobubbles at graphite--water interfaces with different atomic force microscopy modesChih-Wen Yang, Yi-Hsien Lu and Ing-Shouh Hwang
NASA Astrophysics Data System (ADS)
Leadership Team of the IAHR Committee for Hydraulic Machinery and Systems Eduard EGUSQUIZA, UPC Barcelona, Spain, Chair François AVELLAN, EPFL-LMH, Switzerland, Past Chair Richard K FISHER, Voith Hydro Inc., USA, Past Chair Fidel ARZOLA, Edelca, Venezuela Michel COUSTON, Alstom Hydro, France Niklas DAHLBÄCKCK, Vatenfall, Sweden Normand DESY, Andritz VA TECH Hydro Ltd., Canada Chisachi KATO, University of Tokyo, Japan Andrei LIPEJ, Turboinstitut, Slovenija Torbjørn NIELSEN, NTNU, Norway Romeo SUSAN-RESIGA, 'Politehnica' University Timisoara, Romania Stefan RIEDELBAUCH, Stuggart University, Germany Albert RUPRECHT, Stuttgart University, Germany Qing-Hua SHI, Dong Fang Electrical Machinery Co., China Geraldo TIAGO, Universidade Federal de Itajubá, Brazil International Advisory Committee Shouqi YUAN (principal) Jiangsu University China QingHua SHI (principal) Dong Fang Electrical Machinery Co. China Fidel ARZOLA EDELCA Venezuela Thomas ASCHENBRENNER Voith Hydro GmbH & Co. KG Germany Anton BERGANT Litostroj Power doo Slovenia B C BHAOYAL Research & Technology Centre India Hermod BREKKE NTNU Norway Stuart COULSON Voith Hydro Inc. USA Paul COOPER Fluid Machinery Research Inc USA V A DEMIANOV Power Machines OJSC Russia Bart van ESCH Technische Universiteit Eindhoven Netherland Arno GEHRER Andritz Hydro Graz Austria Akira GOTO Ebara Corporation Japan Adiel GUINZBURG The Boeing Company USA D-H HELLMANN KSB AG Germany Ashvin HOSANGADI Combustion Research and Flow Technology USA Byung-Sun HWANG Korea Institute of Material Science Korea Toshiaki KANEMOTO Kyushu Institute of Technology Japan Mann-Eung KIM Korean Register of Shipping Korea Jiri KOUTNIK Voith Hydro GmbH & Co. KG Germany Jinkook LEE Eaton Corporation USA Young-Ho LEE Korea Maritime University Korea Woo-Seop LIM Hyosung Goodsprings Inc Korea Jun MATSUI Yokohama National University Japan Kazuyoshi Mitsubishi H I Ltd, Japan MIYAGAWA Christophe NICOLET Power Vision Engineering Srl Switzerland Maryse PAGE Hydro
EDITORIAL: Power is nothing without control Power is nothing without control
NASA Astrophysics Data System (ADS)
Demming, Anna
review, synthesis of these materials is now a refined art allowing considerable control over the parameters. The mechanisms behind the growth using different techniques is also understood, making the alchemy of creating these prized nanostructures into an advanced science. With these new nanomaterials researchers in nanoscale science and technology now have the power to create devices with performance attributes previously unimagined, and the advancing fine art of controlled synthesis allows these devices to be made on demand. References [1] Kroto H W, Heath J R, O'Brien S C, Curl R F and Smalley R E Nature 318 162-3 [2] Iijima S 1991 Nature B 354 56-8 [3] Journet C, Picher M and Jourdain V 2012 Nanotechnology 23 296-304 [4] Singh N, Zhang T and Lee P S 2009 Nanotechnology 20 195605 [5] Qiu J, Li X, He W, Park S-J, Kim H-K, Hwang Y-H, Lee J-H and Kim Y-D 2009 Nanotechnology 20 155603 [6]Dmitriev S, Lilach Y, Button B, Moskovits M and Kolmakov A 2007 Nanotechnology 18 055707 [7] Hao H L and Shen W Z 2008 Nanotechnology 19 055601 [8] Rocha A R, Martins T B, Fazzio A and da Silva A J R 2010 Nanotechnology 21 345202
Hot electron dynamics in graphene
Ling, Meng-Chieh
Graphene, a two-dimensional (2D) honeycomb structure allotrope of carbon atoms, has a long history since the invention of the pencil [Petroski (1989)] and the linear dispersion band structure proposed by Wallace [Wal]; however, only after Novoselov et al. successively isolated graphene from graphite [Novoselov et al. (2004)], it has been studied intensively during the recent years. It draws so much attentions not only because of its potential application in future electronic devices but also because of its fundamental properties: its quasiparticles are governed by the two-dimensional Dirac equation, and exhibit a variety of phenomena such as the anomalous integer quantum Hall effect (IQHE) [Novoselov et al. (2005)] measured experimentally, a minimal conductivity at vanishing carrier concentration [Neto et al. (2009)], Kondo effect with magnetic element doping [Hentschel and Guinea (2007)], Klein tunneling in p-n junctions [Cheianov and Fal'ko (2006), Beenakker (2008)], Zitterbewegung [Katsnelson (2006)], and Schwinger pair production [Schwinger (1951); Dora and Moessner (2010)]. Although both electron-phonon coupling and photoconductivity in graphene also draws great attention [Yan et al. (2007); Satou et al. (2008); Hwang and Sarma (2008); Vasko and Ryzhii (2008); Mishchenko (2009)], the nonequilibrium behavior based on the combination of electronphonon coupling and Schwinger pair production is an intrinsic graphene property that has not been investigated. Our motivation for studying clean graphene at low temperature is based on the following effect: for a fixed electric field, below a sufficiently low temperature linear eletric transport breaks down and nonlinear transport dominates. The criteria of the strength of this field [Fritz et al. (2008)] is eE = T2/~vF (1.1) For T >√eE~vF the system is in linear transport regime while for T <√eE~vF the system is in nonlinear transport regime. From the scaling's point of view, at the nonlinear transport regime
PREFACE: International Conference on Strongly Correlated Electron Systems (SCES 2011)
NASA Astrophysics Data System (ADS)
Littlewood, P. B.; Lonzarich, G. G.; Saxena, S. S.; Sutherland, M. L.; Sebastian, S. E.; Artacho, E.; Grosche, F. M.; Hadzibabic, Z.
require us to understand electrochemistry on the scale of a single atom; and we already know that the only prospect for effective high temperature superconductivity involves strongly correlated materials. Even novel IT technologies are now seen to have value not just for novel function but also for efficiency. While strongly correlated electron systems continue to excite researchers and the public alike due to the fundamental science issues involved, it seems increasingly likely that support for the science will be leveraged by its impact on energy and sustainability. The conference owes its success to the large number of devoted workers for the cause, which includes the organising and programme committees and a considerable number of workers on the ground who contributed to the smooth running of the meeting. The conference received major sponsorship from CamCool Research Limited, the International Institute for Complex Adaptive Matter, from the European Science Foundation through the program INTELBIOMAT, and the Cambridge Central Asia Forum. On behalf of Conference Chairs: P B Littlewood and G G Lonzarich Secretary: S Saxena Treasurer: M Sutherland Local Organising Committee Chair: S E Sebastian Programme Committee Chairs: E Artacho, F M Grosche, Z Hadzibabic (The PDF file also contains photographs from the conference.) Programme Committee E. Artacho, Cambridge (chair)D. Cox, DavisM. Norman, Argonne M. Grosche, Cambridge (chair)H. Ding, IOP, ChinaY. Onuki, Osaka Z. Hadzibabic, Cambridge (chair)M. Ellerby, LondonC. Panagopoulos, Singapore H. Alloul, Paris Z. Fisk, IrvineS. Ramakrishnan, Mumbai E. Baggio-Saitovich, Rio Di JaneiroJ. Flouquet, GrenobleA. Ramirez, Santa Cruz E. Bauer, ViennaA. Galatanu, RomaniaF. Rivadulla, Compostela N. Berloff, CambridgeP. Gegenwart, GottingenS. E. Sebastian, Cambridge D. Bonn, VancouverL. Greene, UrbanaV. Sechovsky, Prague J. van den Brink, DresdenH. Hwang, TokyoS. Simon, Oxford R. Budhani, DelhiA. P. Mackenzie, St.AndrewsD. Snoke
EDITORIAL: Non-volatile memory based on nanostructures Non-volatile memory based on nanostructures
NASA Astrophysics Data System (ADS)
Kalinin, Sergei; Yang, J. Joshua; Demming, Anna
barrier width in tunnelling experiments, resulting in memristive ionic switching. These phenomena must be differentiated from intrinsic physical polarization switching effects. Similar analysis of solid-state electrochemistry versus physical mechanisms is also important for future research in all areas of oxide materials. In an age where miniaturised computer components can enable GPS tracking, internet access and even the remote operation of machinery from a mobile phone, there is an endearing quaintness associated with images of the large rooms rammed with wires and boxes that comprised early computers. Yet there was a time when these cumbersome devices were state of the art. When the electronic numerical integrator and computer (ENIAC) was developed it achieved speeds one thousand times faster than previous electromechanical machines, a leap in processing power that has not been achieved since. It is easy to imagine future generations looking back on the slow start up and shut down times and high energy consumption of today's computers with a similar wry smile. The articles in this special issue on non-volatile memory based on nanostructures present the very latest research into the next generation's device technology, which may eventually consign today's cutting edge electronics to the history books. References [1] Ryu S W et al 2011 Nanotechnology 22 254005 [2] Miao F, Yang J J, Borghetti J, Medeiros-Ribeiro G and Williams R S 2011 Nanotechnology 22 254007 [3] Strachan J P, Strukov D B, Borghetti J, Yang J J, Medeiros-Ribeiro G and Williams R S 2011 Nanotechnology 22 245015 [4] Kim K M, Choi B J, Lee M H, Kim G H, Song S J, Seok J Y, Yoon J H, Han S and Hwang C S 2011 Nanotechnology 22 254010 [5] Seo K et al 2011 Nanotechnology 22 254023 [6] Garcia V, Fusil S, Bouzehouane K, Enouz-Vedrenne S, Mathur N D, Barthelemy A and Bibes M 2009 Nature 460 81-4 [7] Maksymovych P, Jesse S, Yu P, Ramesh R, Baddorf A P and Kalinin S V 2009 Science 324 1421 [8] Seidel J et al 2009
EDITORIAL: Physical behaviour at the nanoscale: a model for fertile research Physical behaviour at the nanoscale: a model for fertile research
NASA Astrophysics Data System (ADS)
Demming, Anna
Nature 453 80-3 [10] Yang J J, Miao F, Pickett M D, Ohlberg D A A, Stewart D R, Lau C N and Williams R S 2009 The mechanism of electroforming of metal oxide memristive switches Nanotechnology 20 215201 [11] Seo K, Kim I, Jung S, Jo M, Park S, Park J, Shin J and Hwang H 2011 Analog memory and spike-timing-dependent plasticity characteristics of a nanoscale titanium oxide bilayer resistive switching device Nanotechnology 22 254023
EDITORIAL: Focus on Dilute Magnetic Semiconductors FOCUS ON DILUTE MAGNETIC SEMICONDUCTORS
NASA Astrophysics Data System (ADS)
Chambers, Scott A.; Gallagher, Bryan
Chisholm, J D Budai and D P Norton Role of charge carriers for ferromagnetism in cobalt-doped rutile TiO2 T Fukumura, H Toyosaki, K Ueno, M Nakano and M Kawasaki Ab-initio study of exchange constants and electronic structure in diluted magnetic group-IV semiconductors Silvia Picozzi and Marjana Ležaić Phase coherent transport in (Ga,Mn)As D Neumaier, K Wagner, U Wurstbauer, M Reinwald, W Wegscheider and D Weiss Hydrogen interstitials-mediated ferromagnetism in MnxGe1-x magnetic semiconductors Xin-Xin Yao, Shi-Shen Yan, Shu-Jun Hu, Xue-Ling Lin, Chong Han, Yan-Xue Chen, Guo-Lei Liu and Liang-Mo Mei Electronic structures of magnetic semiconductors FeCr2Se4 and Fe0.5Cu0.5Cr2Se4 B I Min, Seung Su Baik, H C Choi, S K Kwon and J-S Kang Investigation of pure and Co2+-doped ZnO quantum dot electronic structures using the density functional theory: choosing the right functional Ekaterina Badaeva, Yong Feng, Daniel R Gamelin and Xiaosong Li Magnetic properties of sol-gel-derived doped ZnO as a potential ferromagnetic semiconductor: a synchrotron-based study N R S Farley, K W Edmonds, A A Freeman, G van der Laan, C R Staddon, D H Gregory and B L Gallagher Local electronic structure of Cr in the II-VI diluted ferromagnetic semiconductor Zn1-xCrxTe M Kobayashi, Y Ishida, J I Hwang, G S Song, A Fujimori, C S Yang, L Lee, H-J Lin, D J Huang, C T Chen, Y Takeda, K Terai, S-I Fujimori, T Okane, Y Saitoh, H Yamagami, K Kobayashi, A Tanaka, H Saito and K Ando Lack of ferromagnetism in n-type cobalt-doped ZnO epitaxial thin films T C Kaspar, T Droubay, S M Heald, P Nachimuthu, C M Wang, V Shutthanandan, C A Johnson, D R Gamelin and S A Chambers XMCD studies on Co and Li doped ZnO magnetic semiconductors Thomas Tietze, Milan Gacic, Gisela Schütz, Gerhard Jakob, Sebastian Brück and Eberhard Goering Ferromagnetic semiconductors and the role of disorder B W Wessels An extensive comparison of anisotropies in MBE grown (Ga,Mn)As material C Gould, S Mark, K Pappert, R G Dengel, J Wenisch, R P