WorldWideScience

Sample records for university residence halls

  1. The Development of a Tutor Programme in a University Hall of Residence--A Case Study.

    Science.gov (United States)

    Beasley, V. J.

    The tutor system within a university hall of residence at Flinders University of South Australia and a method of inquiry used to study the system are examined. Interviews with residence hall tutors revealed four concerns: the need for guidelines, the nature of academic tutoring, pastoral care and its implications, and communication channels within…

  2. Students' Perceptions of the Residence Hall Living Environment at Kuwait University

    Science.gov (United States)

    Al Kandari, Nabila

    2007-01-01

    The purpose of this study is to explore students' perceptions of the residence hall living environment at Kuwait University. The researcher developed a questionnaire for this purpose that included 36 items. The sample of the study consisted of 191 residential students, of whom 98 were male and 93 were female. The research findings indicated that:…

  3. The effect of hand hygiene on illness rate among students in university residence halls.

    Science.gov (United States)

    White, Cindy; Kolble, Robin; Carlson, Rebecca; Lipson, Natasha; Dolan, Mike; Ali, Yusuf; Cline, Mojee

    2003-10-01

    Several studies have indicated a connection between hand sanitization and infection control in numerous settings such as extended care facilities, schools, and hospitals. The purpose of this study was to assess the effectiveness of both a hand-hygiene message campaign and the use of an alcohol gel hand sanitizer in decreasing the incidence of upper-respiratory illness among students living in university residence halls. This study involved a total of 430 students recruited from 4 residence halls during the fall semester at the University of Colorado at the Boulder campus. Dormitories were paired into control and product groups. In the product groups, alcohol gel hand-sanitizer dispensers were installed in every room, bathroom, and dining hall. The data were statistically analyzed for the differences between product and control groups in reported symptoms, illness rates, and absenteeism from classes. The overall increase in hand-hygiene behavior and reduction in symptoms, illness rates, and absenteeism between the product group and control group was statistically significant. Reductions in upper respiratory-illness symptoms ranged from 14.8% to 39.9%. Total improvement in illness rate was 20%. The product group had 43% less missed school/work days. Hand-hygiene practices were improved with increased frequency of handwashing through increasing awareness of the importance of hand hygiene, and the use of alcohol gel hand sanitizer in university dormitories. This resulted in fewer upper respiratory-illness symptoms, lower illness rates, and lower absenteeism.

  4. Involving Students in Residence Halls in Hong Kong

    Science.gov (United States)

    Ting, S. Raymond; Chan, Rebecca; Lee, Esther

    2016-01-01

    This article reports a study based on A. W. Astin's (1984) involvement theory applied in residence halls at a public university in Hong Kong, China. The resident students who were involved as participants or student leaders in this study were found to be better developed in terms of leadership, career development, multicultural experience,…

  5. Style of Life and Student Personnel Policy in College Residence Halls

    Science.gov (United States)

    White, Julie E.

    1969-01-01

    Doctoral dissertation, Dimensions of Conformity and Evasion in Residence Halls for University Women: A Sociological Analysis of Normative Behavior in a Large-Scale Social Organization, 1962, University of Illinois, Urbana.

  6. "Are You as Hard as 50 Cent? Negotiating Race and Masculinity in the Residence Halls

    Science.gov (United States)

    Jaggers, Dametraus; Iverson, Susan V.

    2012-01-01

    In a qualitative study of Black undergraduate men at a predominantly White university in the Midwest, participants shared their experiences in residence halls, including roommate conflicts, interracial tensions, and disagreements with residence hall staff. This article focuses on Black male undergraduates' negotiation of racialized conceptions of…

  7. "Are You as Hard as 50 Cent?" Negotiating Race and Masculinity in the Residence Halls

    Science.gov (United States)

    Jaggers, Dametraus; Iverson, Susan V.

    2012-01-01

    In a qualitative study of Black undergraduate men at a predominantly White university in the Midwest, participants shared their experiences in residence halls, including roommate conflicts, interracial tensions, and disagreements with residence hall staff. This article focuses on Black male undergraduates' negotiation of racialized conceptions of…

  8. Energy-related environmental and economic performance analysis of two different types of electrically heated student residence halls

    Science.gov (United States)

    Amber, Khuram Pervez; Aslam, Muhammad Waqar

    2018-03-01

    Student residence halls occupy 26% of the total area of a typical university campus in the UK and are directly responsible for 24% of university's annual CO2 emissions. Based on five years measured data, this paper aims to investigate the energy-related environmental and economic performance of electrically heated residence halls in which space heating is provided by two different types of electric heaters, that is, panel heater (PHT) and storage heater (SHT). Secondly, using statistical and machine learning methods, the paper attempts to investigate the relationship between daily electricity consumption and five factors (ambient temperature, solar radiation, relative humidity, wind speed and type of day). Data analysis revealed that electricity consumption of both halls is mainly driven by ambient temperature only, whereas SHT residence has 39% higher annual electricity bill and emits 70% higher CO2 emissions on a per square metre basis compared to the PHT residence hall.

  9. The Actively Caring for People Movement at Virginia Tech and Beyond: Cultivating Compassion and Relationships in Residence Halls

    Science.gov (United States)

    McCarty, Shane M.; Mullins, Taris G.; Geller, E. Scott; Shushok, Frank, Jr.

    2013-01-01

    A professor and a group of student leaders initiated the Actively Caring for People (AC4P) Movement to establish a more civil, compassionate, and inclusive culture by inspiring intentional acts of kindness. This article explores the AC4P Movement in a first-year residence hall at Virginia Tech and a second-year residence hall at University of…

  10. A Residential Paradox?: Residence Hall Attributes and College Student Outcomes

    Science.gov (United States)

    Bronkema, Ryan; Bowman, Nicholas A.

    2017-01-01

    The researchers of this brief observed that few environments have the potential to shape the outcomes of college students as much as residence halls. As a result, residence halls have the capacity to foster a strong sense of community as well as other important outcomes such as college satisfaction and academic achievement. However, given the high…

  11. The Marketing of Residence Halls: A Question of Positioning.

    Science.gov (United States)

    Parker, R. Stephen; And Others

    1996-01-01

    A survey of 343 college residence hall directors revealed percentages of private and public institutions offering different amenities, main selling points in promotional brochures, and the most common resident complaints. Results were compared with those of a resident survey concerning the importance of various housing attributes. Implications for…

  12. Alcohol Trajectories over Three Years in a Swedish Residence Hall Student Population

    Directory of Open Access Journals (Sweden)

    Henriettae Ståhlbrandt

    2010-03-01

    Full Text Available Although it is known that college students have a high alcohol consumption, less is known about the long-term drinking trajectories amongst college students and, in particular, students living in residence halls, known to be high-risk drinkers. Over four consecutive years, the drinking habits of 556 Swedish residence hall students were analyzed. The main instruments for measuring outcome were AUDIT (Alcohol Use Identification Disorders Test, SIP (Short Index of Problems and eBAC (estimated Blood Alcohol Concentration. The drinking trajectories among Swedish residence hall students showed stable and decreasing drinking patterns, with age and gender being predictors of group membership.

  13. Residence Hall Student Satisfaction with Interim Alcohol Policy. Office for Student Affairs Research Bulletin; v15 n4 Jul74.

    Science.gov (United States)

    Seabourg, Deborah; And Others

    At the beginning of the 1973-74 academic year alcohol usage was officially permitted for the first time in residence halls at the Twin Cities Campus of the University of Minnesota. To determine residents' perceptions of the effects of the change in drinking policy, interviews were conducted with 49 current dormitory residents, who had also lived…

  14. Sleep quality and some factors affecting sleep quality in the students living in the residence hall of a university

    Directory of Open Access Journals (Sweden)

    Ozge Yavuz Sari

    2015-04-01

    Full Text Available AIM: Sleep disorders are remarkable public health problems as they adversely affect physical, mental and social health and may cause accidents and decline in academic performance and labor productivity. Aim of the study is assessing sleep quality and determining some factors affecting sleep quality in the students living in the residence hall of a university. METHOD: It is a cross sectional study conducted with 277 students, 180 of whom are female. Data were collected via a questionnaire including Pittsburgh Sleep Quality Index (PSQI, Epworth Sleepiness Scale (ESS and socio-demographic characteristics query. RESULTS: According to PSQI, 41.1% of students have bad sleep quality. Sleep quality of male students and students who are overweight/obese or living in more crowded rooms in the hall of residence is worse than other students and #8217;. Prevalence of bad sleep quality is higher in medication users, participants thinking that they have problems in sleeping or falling asleep and had stressful experience in the last month. The differences between groups were statistically significant. In logistic regression analyzes, using medication (OR=2.54, having problems in sleep (OR=12.75, having problems in falling asleep (OR=8.83 and bad experiences in the last month (OR=2.66 have effects on sleep quality. CONCLUSIONS: Interventions about sleep disorders are important due to their preventable characteristics. Developing healthy life habits, improving physical conditions and coping with stress will be effective on preventing and treating sleep disorders. [TAF Prev Med Bull 2015; 14(2.000: 93-100

  15. An exploratory cluster randomised trial of a university halls of residence based social norms marketing campaign to reduce alcohol consumption among 1st year students.

    Science.gov (United States)

    Moore, Graham F; Williams, Annie; Moore, Laurence; Murphy, Simon

    2013-04-18

    This exploratory trial examines the feasibility of implementing a social norms marketing campaign to reduce student drinking in universities in Wales, and evaluating it using cluster randomised trial methodology. Fifty residence halls in 4 universities in Wales were randomly assigned to intervention or control arms. Web and paper surveys were distributed to students within these halls (n = 3800), assessing exposure/contamination, recall of and evaluative responses to intervention messages, perceived drinking norms and personal drinking behaviour. Measures included the Drinking Norms Rating Form, the Daily Drinking Questionnaire and AUDIT-C. A response rate of 15% (n = 554) was achieved, varying substantially between sites. Intervention posters were seen by 80% and 43% of students in intervention and control halls respectively, with most remaining materials seen by a minority in both groups. Intervention messages were rated as credible and relevant by little more than half of students, though fewer felt they would influence their behaviour, with lighter drinkers more likely to perceive messages as credible. No differences in perceived norms were observed between intervention and control groups. Students reporting having seen intervention materials reported lower descriptive and injunctive norms than those who did not. Attention is needed to enhancing exposure, credibility and perceived relevance of intervention messages, particularly among heavier drinkers, before definitive evaluation can be recommended. A definitive evaluation would need to consider how it would achieve sufficient response rates, whilst hall-level cluster randomisation appears subject to a significant degree of contamination. ISRCTN: ISRCTN48556384.

  16. The Role of Social Influence on How Residence Hall Inhabitants Respond to Fire Alarms

    Science.gov (United States)

    Leytem, Michael; Stark, Emily

    2016-01-01

    College resident halls pose a threat for a catastrophic event in the case of fire, but little research has examined potential influences on students' responses to fire alarms, particularly the role of social influence in affecting their behaviors. In the current study, residence hall inhabitants reported their knowledge about fire safety, their…

  17. What Residence Hall Staff Need to Know about Dealing with Death.

    Science.gov (United States)

    Jacobs, Bonita; Towns, James E.

    1984-01-01

    Emphasizes the responsibility for residence hall staff to understand the grief process. An adaptation of Kubler-Ross's stages of death has produced helpful techniques for successfully accepting the death. Through understanding these principles, staff can become aware of the grief process and can assist residents. (JAC)

  18. Perceptions about Residence Hall Wingmates and Alcohol-Related Secondhand Effects among College Freshmen

    Science.gov (United States)

    Boekeloo, Bradley O.; Bush, Elizabeth N.; Novik, Melinda G.

    2009-01-01

    Objective: The authors examined the secondhand effects among college freshmen of others' alcohol use and related student characteristics, and perceptions about residence hallmates. Participants: The authors surveyed 509 incoming freshmen residing in predominantly freshman residence halls. Methods: The authors administered a Web-based survey 2…

  19. Hall Sweet Home

    Science.gov (United States)

    Oguntoyinbo, Lekan

    2011-01-01

    Many urban and commuter universities have their sights set on students who are unlikely to connect with the college and likely to fail unless the right strategies are put in place to help them graduate. In efforts to improve retention rates, commuter colleges are looking to an unusual suspect: residence halls. The author discusses how these…

  20. Graphene and the universality of the quantum Hall effect

    DEFF Research Database (Denmark)

    Tzalenchuk, A.; Janssen, T. J.B.M.; Kazakova, O.

    2013-01-01

    The quantum Hall effect allows the standard for resistance to be defined in terms of the elementary charge and Planck's constant alone. The effect comprises the quantization of the Hall resistance in two-dimensional electron systems in rational fractions of RK=h/e2=25812.8074434(84) Ω (Mohr P. J....... the unconventional quantum Hall effect and then present in detail the route, which led to the most precise quantum Hall resistance universality test ever performed.......The quantum Hall effect allows the standard for resistance to be defined in terms of the elementary charge and Planck's constant alone. The effect comprises the quantization of the Hall resistance in two-dimensional electron systems in rational fractions of RK=h/e2=25812.8074434(84) Ω (Mohr P. J....... et al., Rev. Mod. Phys., 84 (2012) 1527), the resistance quantum. Despite 30 years of research into the quantum Hall effect, the level of precision necessary for metrology, a few parts per billion, has been achieved only in silicon and III-V heterostructure devices. In this lecture we show...

  1. Students' Sense of Community in Residence Halls, Social Integration, and First-Year Persistence.

    Science.gov (United States)

    Berger, Joseph B.

    1997-01-01

    Used concepts from community psychology literature to elaborate a revised version of Tinto's model of individual student departure. Employed a longitudinal analysis of 718 college students. Results indicate that students' sense of community in their residence halls was a source of social integration and a precursor to student departure decisions.…

  2. Structural Analysis of the Resident Assistant Cultural Diversity Questionnaire

    Science.gov (United States)

    Johnson, Vanessa D.; Kang, Young-Shin; Thompson, George F.

    2011-01-01

    This study investigated the five-factor structure of the Resident Assistant Cultural Diversity (RACD) instrument, which assesses resident assistant (RA) confidence in addressing issues of cultural diversity in college and university residence halls. The instrument has five components that explore RA confidence: (1) belief in the need for cultural…

  3. Testing a Beverage and Fruit/Vegetable Education Intervention in a University Dining Hall.

    Science.gov (United States)

    Scourboutakos, Mary J; Mah, Catherine L; Murphy, Sarah A; Mazza, Frank N; Barrett, Nathanael; McFadden, Bill; L'Abbé, Mary R

    2017-06-01

    To test the effect of a nutrition intervention that included education and 2 labeling components on students' food choices. Repeat cross-sectional study taking place on 6 dinner occasions before and 6 afterward. The study was conducted during dinner meals in a buffet-style dining hall in a university campus residence, where students paid a set price and consumed all they cared to eat. University students (n = 368 to 510) visited the cafeteria on each of the data collection dates. Fruit and vegetable consumption were encouraged; sugar-sweetened beverage consumption was discouraged using physical activity calorie equivalent labeling. Beverage choices and vegetable/fruit bar visits. Logistic regression was used to compare the proportion of student who selected each beverage, fruit, or vegetable before and after the intervention, while controlling for menu and gender as covariates. There was a significant decrease in the proportion of students selecting a sugar-sweetened beverage before vs after the intervention (49% vs 41%, respectively; P = .004) and an increase in students choosing water (43% vs 54%, respectively; P < .001). There was a significant increase in students who took fruit after the intervention (36%; P < .001) vs before (30%). The number of students visiting the vegetable bar significantly increased from 60% to 72% (P < .001). This intervention may be a way to encourage healthy dietary choices in campus dining halls. Copyright © 2017. Published by Elsevier Inc.

  4. Modular invariance, universality and crossover in the quantum Hall effect

    International Nuclear Information System (INIS)

    Dolan, Brian P.

    1999-01-01

    An analytic form for the conductivity tensor in crossover between two quantum Hall plateaux is derived, which appears to be in good agreement with existing experimental data. The derivation relies on an assumed symmetry between quantum Hall states, a generalisation of the law of corresponding states from rational filling factors to complex conductivity, which has a mathematical expression in terms of an action of the modular group on the upper-half complex conductivity plane. This symmetry implies universality in quantum Hall crossovers. The assumption that the β-function for the complex conductivity is a complex analytic function, together with some experimental constraints, results in an analytic expression for the crossover, as a function of the external magnetic field

  5. The Philosophy of University Housing

    Science.gov (United States)

    Wallace, James A.

    2012-01-01

    This article examines a stated philosophy of university housing and the philosophy's effect on the facilitation of the personal and intellectual growth of students residing in the residence halls and the development of a sense of community. This particular philosophy governs the housing operations at Southern Illinois University at Carbondale.…

  6. Observation of the Zero Hall Plateau in a Quantum Anomalous Hall Insulator

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Yang; Feng, Xiao; Ou, Yunbo; Wang, Jing; Liu, Chang; Zhang, Liguo; Zhao, Dongyang; Jiang, Gaoyuan; Zhang, Shou-Cheng; He, Ke; Ma, Xucun; Xue, Qi-Kun; Wang, Yayu

    2015-09-16

    We report experimental investigations on the quantum phase transition between the two opposite Hall plateaus of a quantum anomalous Hall insulator. We observe a well-defined plateau with zero Hall conductivity over a range of magnetic field around coercivity when the magnetization reverses. The features of the zero Hall plateau are shown to be closely related to that of the quantum anomalous Hall effect, but its temperature evolution exhibits a significant difference from the network model for a conventional quantum Hall plateau transition. We propose that the chiral edge states residing at the magnetic domain boundaries, which are unique to a quantum anomalous Hall insulator, are responsible for the novel features of the zero Hall plateau.

  7. Men's Identity Development: Issues and Implications for Residence Life

    Science.gov (United States)

    Scott, David A.; Livingston, Wade G.; Havice, Pamela A.; Cawthon, Tony W.

    2012-01-01

    Young men struggle with privilege and oppression in college and university residence halls just as they do in other educational and social contexts. While discussions and research about adolescent and adult identity development continue, little attention has focused on how a male student's identity development can impact residence life cultures on…

  8. The Significance of a Building’s Energy Consumption Profiles for the Optimum Sizing of a Combined Heat and Power (CHP System—A Case Study for a Student Residence Hall

    Directory of Open Access Journals (Sweden)

    Khuram Pervez Amber

    2018-06-01

    Full Text Available University buildings, such as student residence halls with year-round consistent energy demands, offer strong opportunities for Combined Heat and Power (CHP systems. The economic and environmental feasibility of a CHP project is strongly linked with its optimum sizing. This study aims to undertake such an assessment for a CHP system for a student residence hall located in London, the United Kingdom (UK. The study also aims to undertake a sensitivity analysis to investigate the effect of different parameters on the project’s economics. Necessary data are collected via interviews with the University’s Energy Manager. Modeling of the CHP system is performed using the London South Bank University (LSBU, London, the UK CHP model. Results demonstrate that optimum sizing of CHP is crucial for achieving higher economic and environmental benefits and strongly depends on the authenticity of the energy consumption data, based on which the CHP is being sized. Use of incorrect energy data could result in an undersized or oversized CHP system, where an oversized system will result in higher negative results compared to an undersized system. Finally, Monto Carlo statistical analysis shows that electricity price is the significant factor that could affect the project’s economics. With an increasing spark gap, the payback period decreases, and vice versa.

  9. Personal finances of residents at three Canadian universities.

    Science.gov (United States)

    Teichman, Joel M H; Matsumoto, Edward; Smart, Michael; Smith, Aspen E; Tongco, Wayne; Hosking, Denis E; MacNeily, Andrew E; Jewett, Michael A S

    2005-02-01

    To address 3 research questions (What financial choices do residents make? Are the financial choices of residents similar to those of the general public? Are the financial choices of surgical residents reasonable?), we examined financial data from Canadian residents. A written survey was administered to 338 residents (103 of them surgical residents) at 3 Canadian training institutions (University of Toronto, Queen's University and University of Manitoba). Resident household cash flows, assets and liabilities were characterized. Finances for residents were compared with those of the general public, by means of the Survey of Household Spending and Survey of Financial Security. Median resident income was 45,000 dollars annually (Can dollars throughout). With a working spouse, median household income was 87,500 dollars. Among residents, 62% had educational debt (median 37,500 dollars), 39% maintained unpaid credit-card balances (median 1750 dollars), 36% did not budget expenses, 25% maintained cash reserves card debts (39% v. 50%, respectively). Surgical residents had income expectations after graduation higher than current billings justified. Fewer surgical (69%) than anesthesiology residents (88%, p card debts. Surgical residents' expectations of future income may be unrealistic. Further study is warranted.

  10. Providing for Disabled Students: University of Grenoble, France.

    Science.gov (United States)

    PEB Exchange, 2000

    2000-01-01

    Examines how France's University of Grenoble provides for its disabled students in its residence halls, including a description of the university's service for disabled service. A hospital/education center where disabled students can receive care and physiotherapy while attending school is highlighted. (GR)

  11. The Impact of a Health Campaign on Hand Hygiene and Upper Respiratory Illness among College Students Living in Residence Halls.

    Science.gov (United States)

    White, Cindy; Kolble, Robin; Carlson, Rebecca; Lipson, Natasha

    2005-01-01

    Hand hygiene is a key element in preventing the transmission of cold and flu viruses. The authors conducted an experimental-control design study in 4 campus residence halls to determine whether a message campaign about hand hygiene and the availability of gel hand sanitizer could decrease cold and flu illness and school and work absenteeism. Their…

  12. Science Hall of Atomic Energy in Research Reactor Institute, Kyoto University

    International Nuclear Information System (INIS)

    Hayashi, Takeo

    1979-01-01

    The Science Hall of Atomic Energy was built as a subsidiary facility of the Research Reactor Institute, Kyoto University. The purpose of this facility is to accept outside demands concerning the application of the research reactor. The building is a two story building, and has the floor area of 901.47 m 2 . There are an exhibition room, a library, and a big lecture room. In the exhibition room, models of the Kyoto University Research Reactor and the Kyoto University Critical Assembly are placed. Various pictures concerning the application of the reactor are on the wall. In the library, people from outside of the Institute can use various books on science. Books for boys and girls are also stocked and used for public use. At the lecture room, various kinds of meeting can be held. (Kato, T.)

  13. Universal intrinsic spin Hall effect

    Czech Academy of Sciences Publication Activity Database

    Sinova, J.; Culcer, D.; Sinitsyn, N. A.; Niu, Q.; Jungwirth, Tomáš; MacDonald, A. H.

    2004-01-01

    Roč. 92, č. 12 (2004), 126603/1-126603/4 ISSN 0031-9007 R&D Projects: GA ČR GA202/02/0912 Institutional research plan: CEZ:AV0Z1010914 Keywords : semiconductor quantum wells * spin-orbit interaction * spin Hall effect Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 7.218, year: 2004

  14. Laurance David Hall.

    Science.gov (United States)

    Coxon, Bruce

    2011-01-01

    An account is given of the life, scientific contributions, and passing of Laurance David Hall (1938-2009), including his early history and education at the University of Bristol, UK, and the synthesis and NMR spectroscopy of carbohydrates and other natural products during ∼20 years of research and teaching at the University of British Columbia in Vancouver, Canada. Lists of graduate students, post-doctoral fellows, and sabbatical visitors are provided for this period. Following a generous endowment by Dr. Herchel Smith, Professor Hall built a new Department of Medicinal Chemistry at Cambridge University, UK, and greatly expanded his researches into the technology and applications of magnetic resonance imaging (MRI) and zero quantum NMR. MRI technology was applied both to medical problems such as the characterization of cartilage degeneration in knee joints, the measurement of ventricular function, lipid localization in animal models of atherosclerosis, paramagnetic metal complexes of polysaccharides as contrast agents, and studies of many other anatomical features, but also to several aspects of materials analysis, including food analyses, process control, and the elucidation of such physical phenomena as the flow of liquids through porous media, defects in concrete, and the visualization of fungal damage to wood. Professor Hall's many publications, patents, lectures, and honors and awards are described, and also his successful effort to keep the Asilomar facility in Pacific Grove, California as the alternating venue for the annual Experimental NMR Conference. Two memorial services for Professor Hall are remembered. Copyright © 2011 Elsevier Inc. All rights reserved.

  15. Commemorative Symposium on the Hall Effect and its Applications

    CERN Document Server

    Westgate, C

    1980-01-01

    In 1879, while a graduate student under Henry Rowland at the Physics Department of The Johns Hopkins University, Edwin Herbert Hall discovered what is now universally known as the Hall effect. A symposium was held at The Johns Hopkins University on November 13, 1979 to commemorate the lOOth anniversary of the discovery. Over 170 participants attended the symposium which included eleven in­ vited lectures and three speeches during the luncheon. During the past one hundred years, we have witnessed ever ex­ panding activities in the field of the Hall effect. The Hall effect is now an indispensable tool in the studies of many branches of condensed matter physics, especially in metals, semiconductors, and magnetic solids. Various components (over 200 million!) that utilize the Hall effect have been successfully incorporated into such devices as keyboards, automobile ignitions, gaussmeters, and satellites. This volume attempts to capture the important aspects of the Hall effect and its applications. It includes t...

  16. The influence of a student's 'home' climate on room temperature and indoor environmental controls use in a modern halls of residence

    OpenAIRE

    Amin, Rucha; Teli, Despoina; James, Patrick; Bourikas, Leonidas

    2016-01-01

    Adaptive comfort theory states that over time people adapt to their normal environment. Therefore, people from different climates are expected to have different thermal preferences and behaviours, which could lead to ‘performance gap’ in buildings with occupants of diverse climate backgrounds. This study investigates the influence of occupants’ thermal history on use of controls and indoor temperature preference in a newly built halls of residence building complex in Southampton, UK, which pr...

  17. Residents' experiences of abuse, discrimination and sexual harassment during residency training. McMaster University Residency Training Programs.

    Science.gov (United States)

    Cook, D J; Liutkus, J F; Risdon, C L; Griffith, L E; Guyatt, G H; Walter, S D

    1996-06-01

    To assess the prevalence of psychological abuse, physical assault, and discrimination on the basis of gender and sexual orientation, and to examine the prevalence and impact of sexual harassment in residency training programs. Self-administered questionnaire. McMaster University, Hamilton, Ont. Residents in seven residency training programs during the academic year from July 1993 to June 1994. Of 225 residents 186 (82.7%) returned a completed questionnaire, and 50% of the respondents were women. Prevalence of psychological abuse, physical assault and discrimination on the basis of gender and sexual orientation experienced by residents during medical training, prevalence and residents' perceived frequency of sexual harassment. Psychological abuse was reported by 50% of the residents. Some of the respondents reported physical assault, mostly by patients and their family members (14.7% reported assaults by male patients and family members, 9.8% reported assaults by female patients and family members), 5.4% of the female respondents reported assault by male supervising physicians. Discrimination on the basis of gender was reported to be common and was experienced significantly more often by female residents than by male residents (p sexual orientation. Most of the respondents experienced sexual harassment, especially in the form of sexist jokes, flirtation and unwanted compliments on their dress or figure. On average, 40% of the respondents, especially women (p sexual harassment to someone (p sexual harassment were embarassment (reported by 24.0%), anger (by 23.4%) and frustration (20.8%). Psychological abuse, discrimination on the basis of gender and sexual harassment are commonly experienced by residents in training programs. A direct, progressive, multidisciplinary approach is needed to label and address these problems.

  18. A Study of Seton Hall University and the Attributes of Organizational Adaptation Employed in Fashioning Its Catholic Identity and Mission in the Post-Vatican II Era (1966-2006)

    Science.gov (United States)

    Mazza, Nicholas F.

    2009-01-01

    This thesis is the first fully developed and published study of Seton Hall University. It specifically examines the organizational structures of Seton Hall University over a forty year period in light of the tumultuous changes in the Catholic Church and Catholic academia post-Vatican II. Of particular importance is change that influenced the…

  19. Cultivating social learning spaces at an urban Johannesburg university student residence

    OpenAIRE

    Agherdien, Najma

    2015-01-01

    Ph.D. (Education) This case study investigated the conceptualisation and implementation of social learning spaces (SLS) in a University of Johannesburg student residence. The literature base I drew on included ideas, concepts and constructs associated with learning communities [where the terms ‘SLS’ and ‘learning communities’ (LCs) are often used interchangeably], Wenger’s communities of practice, the First Year Experience (FYE), university student residence life and transformation in high...

  20. Universal problems during residency: abuse and harassment.

    Science.gov (United States)

    Nagata-Kobayashi, Shizuko; Maeno, Tetsuhiro; Yoshizu, Misaki; Shimbo, Takuro

    2009-07-01

    Perceived abuse or harassment during residency has a negative impact on residents' health and well-being. This issue pertains not only to Western countries, but also to those in Asia. In order to launch strong international preventive measures against this problem, it is necessary to establish the generality and cultural specificity of this problem in different countries. Therefore, we investigated mistreatment among resident doctors in Japan. In 2007, a multi-institutional, cross-sectional survey was conducted at 37 hospitals. A total of 619 residents (409 men, 210 women) were recruited. Prevalence of mistreatment in six categories was evaluated: verbal abuse; physical abuse; academic abuse; sexual harassment; gender discrimination, and alcohol-associated harassment. In addition, alleged abusers, the emotional effects of abusive experiences, and reluctance to report the abuse to superiors were investigated. Male and female responses were statistically compared using chi-square analysis. A total of 355 respondents (228 men, 127 women) returned a completed questionnaire (response rate 57.4%). Mistreatment was reported by 84.8% of respondents (n = 301). Verbal abuse was the most frequently experienced form of mistreatment (n = 256, 72.1%), followed by alcohol-associated harassment (n = 184, 51.8%). Among women, sexual harassment was also often reported (n = 74, 58.3%). Doctors were most often reported as abusers (n = 124, 34.9%), followed by patients (n = 77, 21.7%) and nurses (n = 61, 17.2%). Abuse was reported to have occurred most frequently during surgical rotations (n = 98, 27.6%), followed by rotations in departments of internal medicine (n = 76, 21.4%), emergency medicine (n = 41, 11.5%) and anaesthesia (n = 40, 11.3%). Very few respondents reported their experiences of abuse to superiors (n = 36, 12.0%). The most frequent emotional response to experiences of abuse was anger (n = 84, 41.4%). Mistreatment during residency is a universal phenomenon. Deliberation

  1. Quantum Hall effect in quantum electrodynamics

    International Nuclear Information System (INIS)

    Penin, Alexander A.

    2009-01-01

    We consider the quantum Hall effect in quantum electrodynamics and find a deviation from the quantum-mechanical prediction for the Hall conductivity due to radiative antiscreening of electric charge in an external magnetic field. A weak dependence of the universal von Klitzing constant on the magnetic field strength, which can possibly be observed in a dedicated experiment, is predicted

  2. G. Stanley Hall and The Journal of Genetic Psychology: A Note.

    Science.gov (United States)

    Hogan, John D

    2016-01-01

    The Journal of Genetic Psychology (originally called The Pedagogical Seminary) has a complicated history. Known primarily as a journal of development psychology, it was originally intended to be a journal of higher education. In addition, G. Stanley Hall created it, at least in part, to curry favor with Jonas Clark, the benefactor of Clark University. The journal had a cumbersome start, with irregular issues for most of its first decade. Hall was a hands-on editor, often contributing articles and reviews as well as the texts of many of his speeches. A substantial number of additional articles were written by Clark University faculty and fellows where Hall was president. After Hall.s death, the editor became Carl Murchison who eventually left Clark University with the journal and continued to publish it privately until his death. Through the years, the journal has been the source for many classic articles in developmental psychology.

  3. Universal conductance and conductivity at critical points in integer quantum Hall systems.

    Science.gov (United States)

    Schweitzer, L; Markos, P

    2005-12-16

    The sample averaged longitudinal two-terminal conductance and the respective Kubo conductivity are calculated at quantum critical points in the integer quantum Hall regime. In the limit of large system size, both transport quantities are found to be the same within numerical uncertainty in the lowest Landau band, and , respectively. In the second-lowest Landau band, a critical conductance is obtained which indeed supports the notion of universality. However, these numbers are significantly at variance with the hitherto commonly believed value . We argue that this difference is due to the multifractal structure of critical wave functions, a property that should generically show up in the conductance at quantum critical points.

  4. Challenges in Improving Energy Efficiency in a University Campus Through the Application of Persuasive Technology and Smart Sensors

    Directory of Open Access Journals (Sweden)

    Anthony Emeakaroha

    2012-12-01

    Full Text Available The impact of energy consumption and carbon emission in the UK poses a grave challenge. This challenge is particularly high amongst residents of university campuses, where usage of electricity and carbon emission remain invisible to the students. In student residential accommodation, personal choices and social influences affect electricity consumption and ultimately the resultant reduction in carbon emissions. Therefore, innovative solutions are required to change students’ energy consumption behavior, and one promising part of the solution is to present real-time electricity consumption data to students in real-time via a dedicated web platform, while, at the same time, appointing an energy delegate in each hall to induce motivation among the students. The results of some interventions show that immediate energy feedback from smart meters or display devices can provide savings of 5%–15%. However, the situation is different; with the complexity in behavior of our target groups “the students who are living in the halls of residence”, there are economical and environmental aspects to be addressed in these issues, in the campus halls of residence. Therefore, we propose a system to address this issue, by applying smart sensors (real-time electricity data capture, integration of dedicated visual web interface (real-time electricity feedback display and an appointed energy delegate in each hall (a motivator. It is expected that this will motivate students living in the halls of residence to reduce their electricity wastage and, therefore, control the energy cost and also reduce the carbon emissions released into the environment. In the present research, we focus on the University of Kent, Canterbury campus to study energy conservation and carbon emission reduction strategies.

  5. Anomalous Hall effect in ZnxFe3-xO4: Universal scaling law and electron localization below the Verwey transition

    Directory of Open Access Journals (Sweden)

    N. Jedrecy

    2016-08-01

    Full Text Available We show that the well-established universal scaling σxyAHE ∼ σxx1.6 between anomalous Hall and longitudinal conductivities in the low conductivity regime (σxx < 104 Ω−1 cm−1 transforms into the scaling σxyAHE ∼ σxx2 at the onset of strong electron localization. The crossover between the two relations is observed in magnetite-derived ZnxFe3-xO4 thin films where an insulating/hopping regime follows a bad metal/hopping regime below the Verwey transition temperature Tv. Our results demonstrate that electron localization effects come into play in the anomalous Hall effect (AHE modifying significantly the scaling exponent. In addition, the thermal evolution of the anomalous Hall resistivity suggests the existence of spin polarons whose size would decrease below Tv.

  6. Axial Hall effect and universality of holographic Weyl semi-metals

    Energy Technology Data Exchange (ETDEWEB)

    Copetti, Christian; Fernández-Pendás, Jorge; Landsteiner, Karl [Instituto de Física Teórica UAM/CSIC,c/ Nicolás Cabrera 13-15, Cantoblanco, 28049 Madrid (Spain)

    2017-02-28

    The holographic Weyl semimetal is a model of a strongly coupled topological semi-metal. A topological quantum phase transition separates a topological phase with non-vanishing anomalous Hall conductivity from a trivial state. We investigate how this phase transition depends on the parameters of the scalar potential (mass and quartic self coupling) finding that the quantum phase transition persists for a large region in parameter space. We then compute the axial Hall conductivity. The algebraic structure of the axial anomaly predicts it to be 1/3 of the electric Hall conductivity. We find that this holds once a non-trivial renormalization effect on the external axial gauge fields is taken into account. Finally we show that the phase transition also occurs in a top-down model based on a consistent truncation of type IIB supergravity.

  7. A study on evacuation time from lecture halls in Faculty of Engineering, Universiti Putra Malaysia

    Science.gov (United States)

    Othman, W. N. A. W.; Tohir, M. Z. M.

    2018-04-01

    An evacuation situation in any building involves many risks. The geometry of building and high potential of occupant load may affect the efficiency of evacuation process. Although fire safety rules and regulations exist, they remain insufficient to guarantee the safety of all building occupants and do not prevent the dramatic events to be repeated. The main objective of this project is to investigate the relationship between the movement time, travel speed and occupant density during a series of evacuation drills specifically for lecture halls. Generally, this study emphasizes on the movement of crowd within a limited space and includes the aspects of human behaviour. A series of trial evacuations were conducted in selected lecture halls at Faculty of Engineering, Universiti Putra Malaysia with the aim of collecting actual data for numerical analysis. The numerical data obtained during trial evacuations were used to determine the evacuation time, crowd movement and behaviour during evacuation process particularly for lecture halls. The evacuation time and number of occupants exiting from each exit were recorded. Video camera was used to record and observe the movement behaviour of occupants during evacuations. EvacuatioNZ was used to simulate the trials evacuations of DK 5 and the results predicted were compared with experimental data. EvacuatioNZ was also used to predict the evacuation time and the flow of occupants exiting from each door for DK 4 and DK 8.

  8. Staffing and Technology Maximize Dorm Security.

    Science.gov (United States)

    George, Stephen C.

    1996-01-01

    Loyola University of Chicago uses uniformed guards and electronic monitoring to prevent unauthorized entry into its 11 residence halls. Access to all residence halls is regulated by bar-code readers. Student ID cards also have color-coded stickers corresponding to specific residence halls. (MLF)

  9. Experimental Studies of Anode Sheath Phenomena in a Hall Thruster Discharge

    International Nuclear Information System (INIS)

    Dorf, L.; Raitses, Y.; Fisch, N.J.

    2004-01-01

    Both electron-repelling and electron-attracting anode sheaths in a Hall thruster were characterized by measuring the plasma potential with biased and emissive probes [L. Dorf, Y. Raitses, V. Semenov, and N.J. Fisch, Appl. Phys. Let. 84 (2004) 1070]. In the present work, two-dimensional structures of the plasma potential, electron temperature, and plasma density in the near-anode region of a Hall thruster with clean and dielectrically coated anodes are identified. Possible mechanisms of anode sheath formation in a Hall thruster are analyzed. The path for current closure to the anode appears to be the determining factor in the anode sheath formation process. The main conclusion of this work is that the anode sheath formation in Hall thrusters differs essentially from that in the other gas discharge devices, like a glow discharge or a hollow anode, because the Hall thruster utilizes long electron residence times to ionize rather than high neutral pressures

  10. Superstorm Sandy: How the New York University Psychiatry Residency Training Program Weathered the Storm.

    Science.gov (United States)

    Capasso, Rebecca; Adler, Laura

    2016-10-01

    The teaching hospitals of the New York University psychiatry residency program were evacuated and then closed for a minimum of 3 months in the aftermath of Superstorm Sandy. Faculty and residents were deployed to alternate clinical sites. The authors examine the consequences of Superstorm Sandy and its implications for the New York University psychiatry residency training program. A survey was administered to faculty and residents. The authors tabulated 98 surveys, for which 24 % of faculty and 84 % of residents responded. Among respondents, 61 % believed that being involved in the evacuation of the hospitals was a positive experience. During deployment, most (85 %) found being placed with peers and supervisors to be beneficial, but there were significant disruptions. Despite facing multiple challenges including closed facilities, deployment to nonaffiliated hospitals, and exhausted personal resources, the training program continued to provide accredited clinical experiences, a core curriculum, and supervision for psychiatry residents during and after Superstorm Sandy.

  11. Intrinsic Changes: Energy Saving Behaviour among Resident University Students

    Science.gov (United States)

    Black, Rosemary; Davidson, Penny; Retra, Karen

    2010-01-01

    This paper presents the results of a study that explored the effectiveness of three intervention strategies in facilitating energy saving behaviour among resident undergraduate university students. In contrast to a dominant practice of motivating with rewards or competition this study sought to appeal to students' intrinsic motivations. An…

  12. Evacuation Simulation in Kalayaan Residence Hall, up Diliman Using Gama Simulation Software

    Science.gov (United States)

    Claridades, A. R. C.; Villanueva, J. K. S.; Macatulad, E. G.

    2016-09-01

    Agent-Based Modeling (ABM) has recently been adopted in some studies for the modelling of events as a dynamic system given a set of events and parameters. In principle, ABM employs individual agents with assigned attributes and behaviors and simulates their behavior around their environment and interaction with other agents. This can be a useful tool in both micro and macroscale-applications. In this study, a model initially created and applied to an academic building was implemented in a dormitory. In particular, this research integrates three-dimensional Geographic Information System (GIS) with GAMA as the multi-agent based evacuation simulation and is implemented in Kalayaan Residence Hall. A three-dimensional GIS model is created based on the floor plans and demographic data of the dorm, including respective pathways as networks, rooms, floors, exits and appropriate attributes. This model is then re-implemented in GAMA. Different states of the agents and their effect on their evacuation time were then observed. GAMA simulation with varying path width was also implemented. It has been found out that compared to their original states, panic, eating and studying will hasten evacuation, and on the other hand, sleeping and being on the bathrooms will be impedances. It is also concluded that evacuation time will be halved when path widths are doubled, however it is recommended for further studies for pathways to be modeled as spaces instead of lines. A more scientific basis for predicting agent behavior in these states is also recommended for more realistic results.

  13. Can ensemble condition in a hall be improved and measured?

    DEFF Research Database (Denmark)

    Gade, Anders Christian

    1988-01-01

    of the ceiling reflectors; and (c) changing the position of the orchestra on the platform. These variables were then tested in full scale experiments in the hall including subjective evaluation by the orchestra in order to verify their effects under practical conditions. New objective parameters, which showed......In collaboration with the Danish Broadcasting Corporation an extensive series of experiments has been carried out in The Danish Radio Concert Hall with the practical purpose of trying to improve the ensemble conditions on the platform for the resident symphony orchestra. First, a series...... very high correlations with the subjective data, also made it possible to compare the improvements with conditions as recently measured in famous European Halls. Besides providing the needed results, the experiments also shed some light on how musicians change their criteria for judging acoustic...

  14. Text messaging among residents and faculty in a university general surgery residency program: prevalence, purpose, and patient care.

    Science.gov (United States)

    Shah, Dhruvil R; Galante, Joseph M; Bold, Richard J; Canter, Robert J; Martinez, Steve R

    2013-01-01

    There is little information about the use of text messaging (texting) devices among resident and faculty physicians for patient-related care (PRC). To determine the prevalence, frequency, purpose, and concerns regarding texting among resident and attending surgeons and to identify factors associated with PRC texting. E-mail survey. University medical center and its affiliated hospitals. Surgery resident and attending staff. Prevalence, frequency, purpose, and concerns regarding patient-related care text messaging. Overall, 73 (65%) surveyed physicians responded, including 45 resident (66%) and 28 attending surgeons (62%). All respondents owned a texting device. Majority of surgery residents (88%) and attendings (71%) texted residents, whereas only 59% of residents and 65% of attendings texted other faculty. Most resident to resident text occurred at a frequency of 3-5 times/d (43%) compared with most attending to resident texts, which occurred 1-2 times/d (33%). Most resident to attending (25%) and attending to attending (30%) texts occurred 1-2 times/d. Among those that texted, PRC was the most frequently reported purpose for resident to resident (46%), resident to attending (64%), attending to resident (82%), and attending to other attending staff (60%) texting. Texting was the most preferred method to communicate about routine PRC (47% of residents vs 44% of attendings). Age (OR: 0.86, 95% CI: 0.79-0.95; p = 0.003), but not sex, specialty/clinical rotation, academic rank, or postgraduate year (PGY) level predicted PRC texting. Most resident and attending staff surveyed utilize texting, mostly for PRC. Texting was preferred for communicating routine PRC information. Our data may facilitate the development of guidelines for the appropriate use of PRC texting. Copyright © 2013 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  15. Localization in a quantum spin Hall system.

    Science.gov (United States)

    Onoda, Masaru; Avishai, Yshai; Nagaosa, Naoto

    2007-02-16

    The localization problem of electronic states in a two-dimensional quantum spin Hall system (that is, a symplectic ensemble with topological term) is studied by the transfer matrix method. The phase diagram in the plane of energy and disorder strength is exposed, and demonstrates "levitation" and "pair annihilation" of the domains of extended states analogous to that of the integer quantum Hall system. The critical exponent nu for the divergence of the localization length is estimated as nu congruent with 1.6, which is distinct from both exponents pertaining to the conventional symplectic and the unitary quantum Hall systems. Our analysis strongly suggests a different universality class related to the topology of the pertinent system.

  16. Quantum critical Hall exponents

    CERN Document Server

    Lütken, C A

    2014-01-01

    We investigate a finite size "double scaling" hypothesis using data from an experiment on a quantum Hall system with short range disorder [1-3]. For Hall bars of width w at temperature T the scaling form is w(-mu)T(-kappa), where the critical exponent mu approximate to 0.23 we extract from the data is comparable to the multi-fractal exponent alpha(0) - 2 obtained from the Chalker-Coddington (CC) model [4]. We also use the data to find the approximate location (in the resistivity plane) of seven quantum critical points, all of which closely agree with the predictions derived long ago from the modular symmetry of a toroidal sigma-model with m matter fields [5]. The value nu(8) = 2.60513 ... of the localisation exponent obtained from the m = 8 model is in excellent agreement with the best available numerical value nu(num) = 2.607 +/- 0.004 derived from the CC-model [6]. Existing experimental data appear to favour the m = 9 model, suggesting that the quantum Hall system is not in the same universality class as th...

  17. Teaching Humanities in Medicine: The University of Massachusetts Family Medicine Residency Program Experience

    Science.gov (United States)

    Silk, Hugh; Shields, Sara

    2012-01-01

    Humanities in medicine (HIM) is an important aspect of medical education intended to help preserve humanism and a focus on patients. At the University of Massachusetts Family Medicine Residency Program, we have been expanding our HIM curriculum for our residents including orientation, home visit reflective writing, didactics and a department-wide…

  18. Measured Early Lateral Energy Fractions in Concert Halls and Opera Houses

    Science.gov (United States)

    BARRON, M.

    2000-04-01

    In the 30 years since early lateral reflections were first suggested as important for concert halls, spatial impression and source broadening have become almost universally accepted as essential characteristics of halls with good acoustics. Two objective measures of source broadening have been proposed. Measured values of the best defined of these measures, the early lateral energy fraction (LF), are considered here. Results from two independent measurement surveys are discussed. Comparisons of LF values by hall show a significant link between hall mean LF and hall width. There is however considerable overlap between measured LF values in different halls so the relevance of describing halls by their mean early lateral energy fraction values is questionable. The behaviour of LF values within auditoria is discussed for different concert hall plan forms and within opera houses. A measure of source broadening including sound level is proposed and results considered in the context of auditorium design.

  19. Hamaoka Atomic Energy Hall, Chubu Electric Power Co. , Inc

    Energy Technology Data Exchange (ETDEWEB)

    Kawasaki, Y [Chubu Electric Power Co. Inc., Nagoya (Japan)

    1979-10-01

    Hamaoka Nuclear Power Station was constructed in the very large site of about 1.6 million m/sup 2/ surrounded by sand dunes and pine forests at the southern tip of Shizuoka Prefecture. Hamaoka Atomic Energy Hall was built on the right side of this power station. This hall had been planned as a part of the works commemorating the 20th anniversary of the founding of the company, and was opened in August, 1972. The building is of steel frame type, and has two floors of 1135 m/sup 2/ total area. The first floor comprises cinema room, power generation corner and open gallery, and the second floor comprises meeting room, native land corner and observation room. Moreover, there is observation platform on the roof. The purpose of the hall is coexistence and coprosperity with the regional residents, and 13 persons make explanations to visitors having reached to 1.9 million as of the end of June, 1979. It is incorporated in the sightseeing route centering around the Omaezaki lighthouse. The cinema hall accommodates 120 men, and the films concerning nuclear power generation and the construction of a nuclear power plant are shown. In the power generation corner, the explanation on nuclear power generation is made with models and panels. The third hall is being built now as energy corner, and it will be completed in autumn, 1979.

  20. Hamaoka Atomic Energy Hall, Chubu Electric Power Co., Inc

    International Nuclear Information System (INIS)

    Kawasaki, Yukio

    1979-01-01

    Hamaoka Nuclear Power Station was constructed in the very large site of about 1.6 million m 2 surrounded by sand dunes and pine forests at the southern tip of Shizuoka Prefecture. Hamaoka Atomic Energy Hall was built on the right side of this power station. This hall had been planned as a part of the works commemorating the 20th anniversary of the founding of the company, and was opened in August, 1972. The building is of steel frame type, and has two floors of 1135 m 2 total area. The first floor comprises cinema room, power generation corner and open gallery, and the second floor comprises meeting room, native land corner and observation room. Moreover, there is observation platform on the roof. The purpose of the hall is coexistence and coprosperity with the regional residents, and 13 persons make explanations to visitors having reached to 1.9 million as of the end of June, 1979. It is incorporated in the sightseeing route centering around the Omaezaki lighthouse. The cinema hall accommodates 120 men, and the films concerning nuclear power generation and the construction of a nuclear power plant are shown. In the power generation corner, the explanation on nuclear power generation is made with models and panels. The third hall is being built now as energy corner, and it will be completed in autumn, 1979. (Kako, I.)

  1. Comparisons of auditorium acoustics measurements as a function of location in halls (A)

    DEFF Research Database (Denmark)

    Bradley, J. S.; Gade, Anders Christian; Siebein, G W

    1993-01-01

    In a measurement tour of nine U.S. concert halls measurements were made at 30 or more combinations of source and receiver position in each hall. Each of the three measurement teams (the University of Florida, the Danish Technical University, and the National Research Council of Canada) made paral....... The measurement results were also used to examine the influence of different measurement equipment and measurement procedures on the within hall variations of the various acoustical quantities. [Work partially supported by the Concert Hall Research Group.]...... parallel measurements of a number of modern room acoustics quantities using different equipment and measurement procedures. These results are compared on a seat-by-seat basis and the differences are explained in terms of earlier systematic studies of the effects of measurement procedure details...

  2. Paired Hall states

    International Nuclear Information System (INIS)

    Greiter, M.

    1992-01-01

    This dissertation contains a collection of individual articles on various topics. Their significance in the corresponding field as well as connections between them are emphasized in a general and comprehensive introduction. In the first article, the author explores the consequences for macroscopic effective Lagrangians of assuming that the momentum density is proportional to the flow of conserved current. The universal corrections obtained for the macroscopic Lagrangian of a superconductor describe the London Hall effect, and provide a fully consistent derivation of it. In the second article, a heuristic principle is proposed for quantized Hall states: the existence and incompressibility of fractionally quantized Hall states is explained by an argument based on an adiabatic localization of magnetic flux, the process of trading uniform flux for an equal amount of fictitious flux attached to the particles. This principle is exactly implemented in the third article. For a certain class of model Hamiltonians, the author obtains Laughlin's Jastrow type wave functions explicitly from a filled Landau level, by smooth extrapolation in quantum statistics. The generalization of this analysis to the torus geometry shows that theorems restricting the possibilities of quantum statistics on closed surfaces are circumvented in the presence of a magnetic field. In the last article, the existence is proposed of a novel incompressible quantum liquid, a paired Hall state, at a half filled Landau level. This state arises adiabatically from free fermions in zero magnetic field, and reduces to a state previously proposed by Halperin in the limit of tightly bound pairs. It supports unusual excitations, including neutral fermions and charge e/4 anyons with statistical parameter θ = π/8

  3. Assembly Hall de la Universidad de Illinois, USA

    Directory of Open Access Journals (Sweden)

    Harrison & Abramovitz, Arquitectos

    1970-05-01

    Full Text Available The Assembly Hall of Illinois University has been constructed with an original reinforced and prestressed concrete structure. It has a seating capacity for 15,565 spectators, in addition to space for press, radio and TV. staff, for the performers, and for invalid spectators who use wheeled chairs. The seating capacity can be further extended by providing 1,500 portable chairs. This hall can be adapted to many uses, and has suitable equipment and installations for assemblies, theatrical and musical performances, ice skating, sports competitions and circus shows. The provision of this magnificent hall has made it possible to organise at the University of Illinois many activities that were not practicable before.Con una original estructura realizada a base de hormigón armado y pretensado ha sido construido el «Assembly Hall», de la Universidad de Illinois, con capacidad para 15.565 espectadores sentados —además de los espacios reservados a los representantes de la prensa, radio y T.V., artistas y espectadores inválidos que acudan en carritos de ruedas—. Puede ser ampliada colocando unas 1.500 sillas portátiles. El edificio está destinado a múltiples usos y dispone de los equipos e instalaciones adecuadas para todo tipo de celebraciones: asambleas, representaciones teatrales y musicales; espectáculos de: circo, patinaje sobre hielo, competiciones deportivas, etc., y ha permitido organizar, en el seno de la Universidad de Illinois, una serie de actividades que antes resultaban imposibles.

  4. Anomalous Hall effect in Zn{sub x}Fe{sub 3-x}O{sub 4}: Universal scaling law and electron localization below the Verwey transition

    Energy Technology Data Exchange (ETDEWEB)

    Jedrecy, N., E-mail: jedrecy@insp.jussieu.fr; Hamieh, M.; Hebert, C.; Escudier, M.; Becerra, L.; Perriere, J. [Institut des Nano Sciences de Paris, UPMC-Sorbonne Universités, CNRS-UMR7588, 4 Place Jussieu, 75252 Paris Cedex 05 (France)

    2016-08-15

    We show that the well-established universal scaling σ{sub xy}{sup AHE} ∼ σ{sub xx}{sup 1.6} between anomalous Hall and longitudinal conductivities in the low conductivity regime (σ{sub xx} < 10{sup 4} Ω{sup −1} cm{sup −1}) transforms into the scaling σ{sub xy}{sup AHE} ∼ σ{sub xx}{sup 2} at the onset of strong electron localization. The crossover between the two relations is observed in magnetite-derived Zn{sub x}Fe{sub 3-x}O{sub 4} thin films where an insulating/hopping regime follows a bad metal/hopping regime below the Verwey transition temperature T{sub v}. Our results demonstrate that electron localization effects come into play in the anomalous Hall effect (AHE) modifying significantly the scaling exponent. In addition, the thermal evolution of the anomalous Hall resistivity suggests the existence of spin polarons whose size would decrease below T{sub v}.

  5. Crowded Out? The Effect of Nonresident Enrollment on Resident Access to Public Research Universities

    Science.gov (United States)

    Curs, Bradley R.; Jaquette, Ozan

    2017-01-01

    Public universities have pursued nonresident enrollment growth as a solution to the stagnation of state funding. Representatives of public universities often argue that nonresident tuition revenue is an important resource in efforts to finance access for resident students, whereas state policymakers are concerned that nonresident enrollment…

  6. Implementing a Universal Well-Being Assessment to Mitigate Barriers to Resident Utilization of Mental Health Resources.

    Science.gov (United States)

    Sofka, Sarah; Grey, Carl; Lerfald, Nathan; Davisson, Laura; Howsare, Janie

    2018-02-01

    Physician utilization of well-being resources remains low despite efforts to promote use of these resources. We implemented a well-being assessment for internal medicine residents to improve access and use of mental health services. We scheduled all postgraduate year 1 (PGY-1) and PGY-2 residents at West Virginia University for the assessment at our faculty and staff assistance program (FSAP). While the assessment was intended to be universal (all residents), we allowed residents to "opt out." The assessment visit consisted of an evaluation by a licensed therapist, who assisted residents with a wellness plan. Anonymous surveys were distributed to all residents, and means were compared by Student's t test. Thirty-eight of 41 PGY-1 and PGY-2 residents (93%) attended the scheduled appointments. Forty-two of 58 residents (72%, including PGY-3s) completed the survey. Of 42 respondents, 28 (67%) attended the assessment sessions, and 14 (33%) did not. Residents who attended the sessions gave mean ratings of 7.8 for convenience (1, not convenient, to 9, very convenient), and 7.9 for feeling embarrassed if colleagues knew they attended (1, very embarrassed, to 9, not embarrassed). Residents who attended the assessment sessions reported they were more likely to use FSAP services in the future, compared with those who did not attend ( P  barriers to using counseling resources. The majority of residents who participated had a positive view of the program and indicated they would return to FSAP if they felt they needed counseling.

  7. A holographic model for the fractional quantum Hall effect

    Energy Technology Data Exchange (ETDEWEB)

    Lippert, Matthew [Institute for Theoretical Physics, University of Amsterdam,Science Park 904, 1090GL Amsterdam (Netherlands); Meyer, René [Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo,Kashiwa, Chiba 277-8568 (Japan); Taliotis, Anastasios [Theoretische Natuurkunde, Vrije Universiteit Brussel andThe International Solvay Institutes,Pleinlaan 2, B-1050 Brussels (Belgium)

    2015-01-08

    Experimental data for fractional quantum Hall systems can to a large extent be explained by assuming the existence of a Γ{sub 0}(2) modular symmetry group commuting with the renormalization group flow and hence mapping different phases of two-dimensional electron gases into each other. Based on this insight, we construct a phenomenological holographic model which captures many features of the fractional quantum Hall effect. Using an SL(2,ℤ)-invariant Einstein-Maxwell-axio-dilaton theory capturing the important modular transformation properties of quantum Hall physics, we find dyonic diatonic black hole solutions which are gapped and have a Hall conductivity equal to the filling fraction, as expected for quantum Hall states. We also provide several technical results on the general behavior of the gauge field fluctuations around these dyonic dilatonic black hole solutions: we specify a sufficient criterion for IR normalizability of the fluctuations, demonstrate the preservation of the gap under the SL(2,ℤ) action, and prove that the singularity of the fluctuation problem in the presence of a magnetic field is an accessory singularity. We finish with a preliminary investigation of the possible IR scaling solutions of our model and some speculations on how they could be important for the observed universality of quantum Hall transitions.

  8. A holographic model for the fractional quantum Hall effect

    Science.gov (United States)

    Lippert, Matthew; Meyer, René; Taliotis, Anastasios

    2015-01-01

    Experimental data for fractional quantum Hall systems can to a large extent be explained by assuming the existence of a Γ0(2) modular symmetry group commuting with the renormalization group flow and hence mapping different phases of two-dimensional electron gases into each other. Based on this insight, we construct a phenomenological holographic model which captures many features of the fractional quantum Hall effect. Using an -invariant Einstein-Maxwell-axio-dilaton theory capturing the important modular transformation properties of quantum Hall physics, we find dyonic diatonic black hole solutions which are gapped and have a Hall conductivity equal to the filling fraction, as expected for quantum Hall states. We also provide several technical results on the general behavior of the gauge field fluctuations around these dyonic dilatonic black hole solutions: we specify a sufficient criterion for IR normalizability of the fluctuations, demonstrate the preservation of the gap under the action, and prove that the singularity of the fluctuation problem in the presence of a magnetic field is an accessory singularity. We finish with a preliminary investigation of the possible IR scaling solutions of our model and some speculations on how they could be important for the observed universality of quantum Hall transitions.

  9. Impact of Smoke-Free Residence Hall Policies: The Views of Administrators at 3 State Universities

    Science.gov (United States)

    Gerson, Megan

    2005-01-01

    Nationwide efforts to protect the public against the health effects of secondhand smoke have prompted college and university administrators to adopt more restrictive smoking policies. Some campus officials are concerned that new policies will lead to student backlash, increased staff workloads, and an increased economic burden. To understand the…

  10. Investigations of Probe Induced Perturbations in a Hall Thruster

    International Nuclear Information System (INIS)

    D. Staack; Y. Raitses; N.J. Fisch

    2002-01-01

    An electrostatic probe used to measure spatial plasma parameters in a Hall thruster generates perturbations of the plasma. These perturbations are examined by varying the probe material, penetration distance, residence time, and the nominal thruster conditions. The study leads us to recommendations for probe design and thruster operating conditions to reduce discharge perturbations, including metal shielding of the probe insulator and operation of the thruster at lower densities

  11. Increasing First-Semester Student Engagement: A Residential Community Retention Study

    Science.gov (United States)

    Briggs, Ronald

    2012-01-01

    The purpose of this study was to increase first year residential student engagement and participation in residence hall programs during the 2011 fall semester at the Downtown Phoenix Campus of Arizona State University. Six upperclassmen (Taylor Place Leaders) residing in a residence hall (Taylor Place) were matched by academic major with 17 first…

  12. Experimental halls workshop summary

    International Nuclear Information System (INIS)

    Thorndike, A.

    1976-01-01

    On May 26 and 27, 1976, approximately 50 people met for an informal workshop on plans for experimental halls for ISABELLE. Plans as they exist in the May 1976 version of the ISABELLE proposal were presented. Discussions were held on the following four general topics by separate working groups: (1) pros and cons of open areas as compared with enclosed halls; (2) experimental hall needs of ep, anti pp, and other options; (3) hall for the lepton detector; and (4) hall for the hadron spectrometer. The planning for experimental halls at PEP, the hall for the lepton detector, the hadron spectrometer, and open areas are discussed

  13. Chapin Hall Projects and Publications. Autumn 1999.

    Science.gov (United States)

    Chicago Univ., IL. Chapin Hall Center for Children.

    This guide chronicles the ongoing work and writings of the Chapin Hall Center for Children at the University of Chicago, a policy research center dedicated to bringing sound information, rigorous analyses, innovative ideas, and an independent, multidisciplinary perspective to bear on policies and programs affecting children. This guide, organized…

  14. Surveillance on University Students' Living Behaviors in the Private Residence, Prathumthani, Thailand

    Science.gov (United States)

    Luckanavanich, Suwannee

    2011-01-01

    The purpose of this study was to investigate the relationship among lifestyles, personal relationship (friendship and romantic relationship), and living behaviors shared with closed friends and romantic friends. The study undertook a quantitative research of university students' living behaviors in the private residence. A survey questionnaire was…

  15. Experimental halls workshop summary

    International Nuclear Information System (INIS)

    Thorndike, A.

    1976-01-01

    A brief discussion is given of: (1) pros and cons of open areas as compared with enclosed halls; (2) experimental hall needs of ep, anti p p, and other options; (3) hall for the lepton detector; and, (4) hall for the hadron spectrometer

  16. Experimental halls workshop summary

    International Nuclear Information System (INIS)

    Thorndike, A.

    1976-01-01

    At the experimental halls workshop, discussions were held on: (1) open areas as compared with enclosed halls; (2) the needs of ep, anti pp, and other options; (3) the hall for the lepton detector; and (4) the hall for the hadron spectrometer. The value of different possibilities for the future experimental program was explored. A number of suggestions emerged which will be used as the design of the experimental halls progresses

  17. Parity effect of bipolar quantum Hall edge transport around graphene antidots.

    Science.gov (United States)

    Matsuo, Sadashige; Nakaharai, Shu; Komatsu, Katsuyoshi; Tsukagoshi, Kazuhito; Moriyama, Takahiro; Ono, Teruo; Kobayashi, Kensuke

    2015-06-30

    Parity effect, which means that even-odd property of an integer physical parameter results in an essential difference, ubiquitously appears and enables us to grasp its physical essence as the microscopic mechanism is less significant in coarse graining. Here we report a new parity effect of quantum Hall edge transport in graphene antidot devices with pn junctions (PNJs). We found and experimentally verified that the bipolar quantum Hall edge transport is drastically affected by the parity of the number of PNJs. This parity effect is universal in bipolar quantum Hall edge transport of not only graphene but also massless Dirac electron systems. These results offer a promising way to design electron interferometers in graphene.

  18. Topological Hall and spin Hall effects in disordered skyrmionic textures

    KAUST Repository

    Ndiaye, Papa Birame; Akosa, Collins Ashu; Manchon, Aurelien

    2017-01-01

    We carry out a thorough study of the topological Hall and topological spin Hall effects in disordered skyrmionic systems: the dimensionless (spin) Hall angles are evaluated across the energy-band structure in the multiprobe Landauer-Büttiker formalism and their link to the effective magnetic field emerging from the real-space topology of the spin texture is highlighted. We discuss these results for an optimal skyrmion size and for various sizes of the sample and find that the adiabatic approximation still holds for large skyrmions as well as for nanoskyrmions. Finally, we test the robustness of the topological signals against disorder strength and show that the topological Hall effect is highly sensitive to momentum scattering.

  19. Topological Hall and spin Hall effects in disordered skyrmionic textures

    KAUST Repository

    Ndiaye, Papa Birame

    2017-02-24

    We carry out a thorough study of the topological Hall and topological spin Hall effects in disordered skyrmionic systems: the dimensionless (spin) Hall angles are evaluated across the energy-band structure in the multiprobe Landauer-Büttiker formalism and their link to the effective magnetic field emerging from the real-space topology of the spin texture is highlighted. We discuss these results for an optimal skyrmion size and for various sizes of the sample and find that the adiabatic approximation still holds for large skyrmions as well as for nanoskyrmions. Finally, we test the robustness of the topological signals against disorder strength and show that the topological Hall effect is highly sensitive to momentum scattering.

  20. Nematic and Valley Ordering in Anisotropic Quantum Hall Systems

    Science.gov (United States)

    Parameswaran, S. A.; Abanin, D. A.; Kivelson, S. A.; Sondhi, S. L.

    2010-03-01

    We consider a multi-valley two dimensional electron system in the quantum Hall effect (QHE) regime. We focus on QHE states that arise due to spontaneous breaking of the valley symmetry by the Coulomb interactions. We show that the anisotropy of the Fermi surface in each valley, which is generally present in such systems, favors states where all the electrons reside in one of the valleys. In a clean system, the valley ordering occurs via a finite temperature Ising-like phase transition, which, owing to the Fermi surface anisotropy, is accompanied by the onset of nematic order. In a disordered system, domains of opposite polarization are formed, and therefore long-range valley order is destroyed, however, the resulting state is still compressible. We discuss the transport properties in ordered and disordered regimes, and point out the possible relation of our results to recent experiments in AlAs [1]. [1] Y. P. Shkolnikov, S. Misra, N. C. Bishop, E. P. De Poortere, and M. Shayegan, Observation of Quantum Hall ``Valley Skyrmions", Phys. Rev. Lett. 95, 068809 (2005)[2] D.A. Abanin, S.A. Parameswaran, S.A. Kivelson and S.L. Sondhi, Nematic and Valley Ordering in Anisotropic Quantum Hall Systems, to be published.

  1. Academicians and Neurologic Physical Therapy Residents Partner to Expand Clinical Reflection Using the SOLO Taxonomy: A Novel Approach.

    Science.gov (United States)

    Pinto Zipp, Genevieve; Maher, Catherine; Donnelly, Erin; Fritz, Brian; Snowdon, Lauren

    2016-01-01

    Creating curriculums that develop physical therapy (PT) students into evidenced-based, critically reflective, entry-level practitioners is one of the primary goals for PT programs. Academic faculty partnering with neurologic residency programs to design learning environments that capitalize upon the strengths of both can create insightful educational experiences for students during their didactic training. These partnerships support the development of critical thinking skills and provide mentorship for residents transitioning from their role as a clinician to that of an educator. Using the SOLO (structure of observed learning outcomes) taxonomy as a framework for developing learning experiences, Seton Hall University neurologic academic faculty and program directors from the Kessler Institute for Rehabilitation Residency in Neurologic Physical Therapy have built a partnership that seeks to develop critical reflection skills in both the neurologic resident and entry-level PT students. While integration of residents into entry-level PT curriculum may not be novel, we believe that utilizing the SOLO model within this partnership is unique. This paper describes the partnership and learning experiences rooted in the SOLO taxonomy theoretical framework and discusses perceived benefits of this learning experience across professional health science programs.

  2. Hall effect in hopping regime

    International Nuclear Information System (INIS)

    Avdonin, A.; Skupiński, P.; Grasza, K.

    2016-01-01

    A simple description of the Hall effect in the hopping regime of conductivity in semiconductors is presented. Expressions for the Hall coefficient and Hall mobility are derived by considering averaged equilibrium electron transport in a single triangle of localization sites in a magnetic field. Dependence of the Hall coefficient is analyzed in a wide range of temperature and magnetic field values. Our theoretical result is applied to our experimental data on temperature dependence of Hall effect and Hall mobility in ZnO. - Highlights: • Expressions for Hall coefficient and mobility for hopping conductivity are derived. • Theoretical result is compared with experimental curves measured on ZnO. • Simultaneous action of free and hopping conduction channels is considered. • Non-linearity of hopping Hall coefficient is predicted.

  3. Hall effect in hopping regime

    Energy Technology Data Exchange (ETDEWEB)

    Avdonin, A., E-mail: avdonin@ifpan.edu.pl [Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warszawa (Poland); Skupiński, P. [Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warszawa (Poland); Grasza, K. [Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warszawa (Poland); Institute of Electronic Materials Technology, ul. Wólczyńska 133, 01-919 Warszawa (Poland)

    2016-02-15

    A simple description of the Hall effect in the hopping regime of conductivity in semiconductors is presented. Expressions for the Hall coefficient and Hall mobility are derived by considering averaged equilibrium electron transport in a single triangle of localization sites in a magnetic field. Dependence of the Hall coefficient is analyzed in a wide range of temperature and magnetic field values. Our theoretical result is applied to our experimental data on temperature dependence of Hall effect and Hall mobility in ZnO. - Highlights: • Expressions for Hall coefficient and mobility for hopping conductivity are derived. • Theoretical result is compared with experimental curves measured on ZnO. • Simultaneous action of free and hopping conduction channels is considered. • Non-linearity of hopping Hall coefficient is predicted.

  4. How Expectations Do Not Equate with Practice: The Gendered Reality of the Female Resident Assistant

    Science.gov (United States)

    Cousineau, Luc; Chambers, Lori

    2015-01-01

    Residence hall and house employees (resident assistants) at postsecondary institutions in Canada are an important part of the social and rules-based structure that allows these facilities to operate. These employees are challenged with varied situations that require the application of mediation, authoritarian, recognition, and referral skills. To…

  5. Contribution of the study of the Hall Effect. Hall Effect of powder products

    International Nuclear Information System (INIS)

    Cherville, Jean

    1961-01-01

    This research thesis reports the development of an apparatus aimed at measuring the Hall Effect and the magneto-resistance of powders at room temperature and at the liquid nitrogen temperature. The author also proposes a theoretical contribution to the Hall Effect and reports the calculation of conditions to be met to obtain a correct value for the Hall constant. Results are experimentally verified. The method is then applied to the study of a set of powdered pre-graphitic graphites. The author shows that their Hall coefficient confirms the model already proposed by Mrozowski. The study of the Hall Effect of any kind of powders can thus be performed, and the Hall Effect can therefore be a mean to study mineral and organic compounds, and notably powdered biological molecules [fr

  6. Cryogenic microsize Hall sensors

    International Nuclear Information System (INIS)

    Kvitkovic, J.; Polak, M.

    1993-01-01

    Hall sensors have a variety of applications in magnetic field measurements. The active area of the Hall sensor does not play an important role in measuring of homogeneous magnetic field. Actually Hall sensors are widely used to measure profiles of magnetic fields produced by magnetization currents in samples of HTC superconductors, as well as of LTC ones. Similar techniques are used to measure magnetization of both HTC and LTC superconductors. In these cases Hall sensor operates in highly inhomogeneous magnetic fields. Because of that, Hall sensors with very small active area are required. We developed and tested Hall sensors with active area 100 μm x 100 μm - type M and 50 μm x 50 μm - type V. Here we report on the most imporant parameters of these units, as well as on their properties as differential magnetometer. (orig.)

  7. Topological Hall and Spin Hall Effects in Disordered Skyrmionic Textures

    OpenAIRE

    N'diaye, P. B.; Akosa, C. A.; Manchon, A.

    2016-01-01

    We carry out a throughout study of the topological Hall and topological spin Hall effects in disordered skyrmionic systems: the dimensionless (spin) Hall angles are evaluated across the energy band structure in the multiprobe Landauer-B\\"uttiker formalism and their link to the effective magnetic field emerging from the real space topology of the spin texture is highlighted. We discuss these results for an optimal skyrmion size and for various sizes of the sample and found that the adiabatic a...

  8. Tuning giant anomalous Hall resistance ratio in perpendicular Hall balance

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, J. Y.; Yang, G. [Department of Materials Physics and Chemistry, University of Science and Technology Beijing, Beijing 100083 (China); State Key Laboratory of Magnetism, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Wang, S. G., E-mail: sgwang@iphy.ac.cn, E-mail: ghyu@mater.ustb.edu.cn [State Key Laboratory of Magnetism, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Liu, J. L. [State Key Laboratory of Magnetism, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Department of Physics, Beijing University of Aeronautics and Astronautics, Beijing 100191 (China); Wang, R. M. [Department of Physics, Beijing University of Aeronautics and Astronautics, Beijing 100191 (China); Amsellem, E.; Kohn, A. [Department of Materials Engineering, Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer-Sheva 84105 (Israel); Yu, G. H., E-mail: sgwang@iphy.ac.cn, E-mail: ghyu@mater.ustb.edu.cn [Department of Materials Physics and Chemistry, University of Science and Technology Beijing, Beijing 100083 (China)

    2015-04-13

    Anomalous Hall effect at room temperature in perpendicular Hall balance with a core structure of [Pt/Co]{sub 4}/NiO/[Co/Pt]{sub 4} has been tuned by functional CoO layers, where [Pt/Co]{sub 4} multilayers exhibit perpendicular magnetic anisotropy. A giant Hall resistance ratio up to 69 900% and saturation Hall resistance (R{sub S}{sup P}) up to 2590 mΩ were obtained in CoO/[Pt/Co]{sub 4}/NiO/[Co/Pt]{sub 4}/CoO system, which is 302% and 146% larger than that in the structure without CoO layers, respectively. Transmission electron microscopy shows highly textured [Co/Pt]{sub 4} multilayers and oxide layers with local epitaxial relations, indicating that the crystallographic structure has significant influence on spin dependent transport properties.

  9. Rectors of European universities

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    Several rectors of European universities visited CERN recently while in Geneva for a conference on coordination between their institutions. The visit began with a welcome by Roger Cashmore, CERN Director of Collider Programmes,and continued with tours of CMS, ALICE and the LHC magnet assembly hall. Photos 01, 02: The visitors in the ALICE assembly hall: (left to right) Dr. Raymond Werlen, Deputy Secretary-General of the Conference of Rectors of Swiss Universities; visit guide Prof. Alain Blondel, Department of Nuclear and Corpuscular Physics, University of Geneva; Prof. Adriano Pimpão, Rector of the University of Algarve, President of the Council of Rectors of Portuguese Universities; Prof. Jean-Pierre Finance, Conference of University Presidents, France; Prof. Jean-Paul Lehners, Vice-President of the Centre Universitaire, Luxemburg.

  10. The infrared Hall effect in YBCO: Temperature and frequency dependence of Hall scattering

    International Nuclear Information System (INIS)

    Grayson, M.; Cerne, J.; Drew, H.D.; Schmadel, D.C.; Hughes, R.; Preston, J.S.; Kung, P.J.; Vale, L.

    1999-01-01

    The authors measure the Hall angle, θ H , in YBCO films in the far- and mid-infrared to determine the temperature and frequency dependence of the Hall scattering. Using novel modulation techniques they measure both the Faraday rotation and ellipticity induced by these films in high magnetic fields to deduce the complex conductivity tensor. They observe a strong temperature dependence of the mid-infrared Hall conductivity in sharp contrast to the weak dependence of the longitudinal conductivity. By fitting the frequency dependent normal state Hall angle to a Lorentzian θ H (ω) = ω H /(γ H minus iω) they find the Hall frequency, ω H , is nearly independent of temperature. The Hall scattering rate, γ H , is consistent with γ H ∼ T 2 up to 200 K and is remarkably independent of IR frequency suggesting non-Fermi liquid behavior

  11. The fluctuation Hall conductivity and the Hall angle in type-II superconductor under magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Tinh, Bui Duc, E-mail: tinhbd@hnue.edu.vn [Institute of Research and Development, Duy Tan University, K7/25 Quang Trung, Danang (Viet Nam); Department of Physics, Hanoi National University of Education, 136 Xuan Thuy, Cau Giay, Hanoi (Viet Nam); Hoc, Nguyen Quang; Thu, Le Minh [Department of Physics, Hanoi National University of Education, 136 Xuan Thuy, Cau Giay, Hanoi (Viet Nam)

    2016-02-15

    Highlights: • The time-dependent Ginzburg–Landau was used to calculate fluctuation Hall conductivity and Hall angle in type-II superconductor in 2D and 3D. • We obtain analytical expressions for the fluctuation Hall conductivity and the Hall angle summing all Landau levels without need to cutoff higher Landau levels to treat arbitrary magnetic field. • The results were compared to the experimental data on YBCO. - Abstract: The fluctuation Hall conductivity and the Hall angle, describing the Hall effect, are calculated for arbitrary value of the imaginary part of the relaxation time in the frame of the time-dependent Ginzburg–Landau theory in type II-superconductor with thermal noise describing strong thermal fluctuations. The self-consistent Gaussian approximation is used to treat the nonlinear interaction term in dynamics. We obtain analytical expressions for the fluctuation Hall conductivity and the Hall angle summing all Landau levels without need to cutoff higher Landau levels to treat arbitrary magnetic field. The results are compared with experimental data on high-T{sub c} superconductor.

  12. Partnership in Learning between University and School: Evidence from a Researcher-in-Residence

    Science.gov (United States)

    Young, Ann-Marie; O'Neill, Amy; Mooney Simmie, Geraldine

    2015-01-01

    The status of school placement in the Republic of Ireland has recently been elevated in importance within a reconceptualisation of initial teacher education (ITE). This paper shares the findings from one case study of a school--university partnership enacted in this regard. The partnership involved a researcher-in-residence at the school…

  13. The study of knowledge and attitude of new coming residents in cardiopulmonary resuscitation in Tehran University of Medical Sciences, 1377-78

    Directory of Open Access Journals (Sweden)

    Haj Zeinali AM

    2000-09-01

    Full Text Available Cardiopulmonary resuscitation (CPR is one of the most important skills that every body must know it in medical services. In educational hospitals, the (Newly-arrived residents are in first cell for management of victims, specially in emergency rooms and at nights. Their knowledge and ability for successful CPR have a direct relation with prevalence of total mortality and morbidity. This research has assessed the knowledge and attitude of the new residents about CPR, and for answering to this question: "Is the CPR workshops necessary for all of the new residents in the beginning of their courses". All of the 506 new residents were examined simultaneously in 2 separate years with a questionnaire consist of 50 questions about their CPR secence and skills and 8 questions about their attitude in CPR. These informations were analyzed by SPSS and EPI6 softwares. The mean correct answers were 55%±11.8. The best results were about arrythmias (68.6% and airway management (63.6% and the worst were about IV access (43.1% and pediatric CPR (31.5%. These findings were similar in 2 sequential years. Their knowledge had significant relation with sex (P=0.002, their original university (P=0.031, their residency course (P=0.024 and their residency reception scores (P<0.001. Males and knowledge more than females. The max scores were from Kerman (62% and Beheshti universities (60.5% and the min score were from Hamadan (48% and Kashan universities (37%. The orthopedic (62.5% and urologic residents (61.6% had the most knowledge and the gynecology residents (53.8% had the least. The knowledge had no relation with the time of graduation. About their attitude in CPR: Their knowledge was moderate (65.8%, their abilities was moderate (58% and their education about CPR in MD course had been low (51.5%. Their references for education had been individual studies (74.6%, CPR workshop had not been condected in the most universities (92.7%. knowledge about CPR is low (55

  14. Skyrmions and Hall viscosity

    Science.gov (United States)

    Kim, Bom Soo

    2018-05-01

    We discuss the contribution of magnetic Skyrmions to the Hall viscosity and propose a simple way to identify it in experiments. The topological Skyrmion charge density has a distinct signature in the electric Hall conductivity that is identified in existing experimental data. In an electrically neutral system, the Skyrmion charge density is directly related to the thermal Hall conductivity. These results are direct consequences of the field theory Ward identities, which relate various physical quantities based on symmetries and have been previously applied to quantum Hall systems.

  15. Correlates of University Students’ Soft and Energy Drink Consumption According to Gender and Residency

    Science.gov (United States)

    Deliens, Tom; Clarys, Peter; De Bourdeaudhuij, Ilse; Deforche, Benedicte

    2015-01-01

    This study assessed personal and environmental correlates of Belgian university students’ soft and energy drink consumption and investigated whether these associations were moderated by gender or residency. Four hundred twenty-five university students completed a self-reported on-line questionnaire assessing socio-demographics, health status, soft and energy drink consumption, as well as personal and environmental factors related to soft and energy drink consumption. Multiple linear regression analyses were conducted. Students believing soft drink intake should be minimized (individual subjective norm), finding it less difficult to avoid soft drinks (perceived behavioral control), being convinced they could avoid soft drinks in different situations (self-efficacy), having family and friends who rarely consume soft drinks (modelling), and having stricter family rules about soft drink intake were less likely to consume soft drinks. Students showing stronger behavioral control, having stricter family rules about energy drink intake, and reporting lower energy drink availability were less likely to consume energy drinks. Gender and residency moderated several associations between psychosocial constructs and consumption. Future research should investigate whether interventions focusing on the above personal and environmental correlates can indeed improve university students’ beverage choices. PMID:26258790

  16. Particle-in-cell simulations of Hall plasma thrusters

    Science.gov (United States)

    Miranda, Rodrigo; Ferreira, Jose Leonardo; Martins, Alexandre

    2016-07-01

    Hall plasma thrusters can be modelled using particle-in-cell (PIC) simulations. In these simulations, the plasma is described by a set of equations which represent a coupled system of charged particles and electromagnetic fields. The fields are computed using a spatial grid (i.e., a discretization in space), whereas the particles can move continuously in space. Briefly, the particle and fields dynamics are computed as follows. First, forces due to electric and magnetic fields are employed to calculate the velocities and positions of particles. Next, the velocities and positions of particles are used to compute the charge and current densities at discrete positions in space. Finally, these densities are used to solve the electromagnetic field equations in the grid, which are interpolated at the position of the particles to obtain the acting forces, and restart this cycle. We will present numerical simulations using software for PIC simulations to study turbulence, wave and instabilities that arise in Hall plasma thrusters. We have sucessfully reproduced a numerical simulation of a SPT-100 Hall thruster using a two-dimensional (2D) model. In addition, we are developing a 2D model of a cylindrical Hall thruster. The results of these simulations will contribute to improve the performance of plasma thrusters to be used in Cubesats satellites currenty in development at the Plasma Laboratory at University of Brasília.

  17. Using the Leaderless Group Discussion Technique for the Selection of Residence Hall Counselors

    Science.gov (United States)

    Banta, Trudy W.; McCormick, Jane E.

    1969-01-01

    Describes successful effort to involve head residents in selection responsibilities. Discusses use of Record of Previous Leadership Experience, behavior ratings adapted from Interview and LGD Rating Scale (T. W. Banta) recommendation from head resident as selection criteria. (CJ)

  18. Energy consumption of sport halls

    Energy Technology Data Exchange (ETDEWEB)

    1983-01-01

    The energy consumption of Finland's sports halls (ball games halls, ice hockey halls and swimming halls) represent approximately 1% of that of the country's whole building stock. In the light of the facts revealed by the energy study the potential energy saving rate in sports halls is 15-25%. The total savings would be something like FIM 30-40 million per annum, of which about a half would be achieved without energy-economic investments only by changing utilization habits and by automatic control measures. The energy-economic investments are for the most part connected with ventilation and their repayment period is from one to five years. On the basis of the energy study the following specific consumption are presented as target values: swimming halls: heat (kWh/m*H3/a)100, electricity (kWh/m*H3/a)35, water (l/m*H3/a)1000 icehockey halls (warm): heat (kWh/m*H3/a)25, electricity (kWh/m*H3/a)15, water (l/m*H3/a)200, ball games halls (multi-purpose halls): heat (kWh/m*H3/a)30, electricity (kWh/m*H3/a)25, water (l/m*H3/a)130. In the study the following points proved to be the central areas of energy saving in sports halls: 1. Flexible regulation of the temperature in sports spaces on the basis of the sport in question. 2. The ventilation of swimming halls should be adjusted in such a way that the humidity of the hall air would comply with the limit humidity curve determined by the quality of structures and the temperature of the outdoor air. 3. An ice skating hall is an establishment producing condensing energy from 8 to 9 months a year worth of approx. 100.000-150.000 Finnmarks. The development of the recovery of condensing energy has become more important. 4. The ventilation of ball games halls may account for over 50% of the energy consumption of the whole building. Therefore special attention should be paid to the optimatization of ventilation as a whole.

  19. Anomalous Hall effect and Nernst effect in itinerant ferromagnets

    International Nuclear Information System (INIS)

    Asamitsu, A.; Miyasato, T.; Abe, N.; Fujii, T.; Onose, Y.; Onoda, S.; Nagaosa, N.; Tokura, Y.

    2007-01-01

    Anomalous Hall effect (AHE) and anomalous Nernst effect (ANE) in many ferromagnetic metals including pure metals, oxides, and calcogenides, are studied to obtain unified understandings of their origins. We show the universal behavior of anomalous Hall conductivity σ xy as a function of longitudinal conductivity σ xx over six orders of magnitude, which is well reproduced by rigorous unified theory assuming both intrinsic and extrinsic contributions to the AHE. ANE is closely related with AHE and gives us further information about the electronic state in the ground state of ferromagnets. The temperature dependence of transverse Peltier coefficient α xy shows almost similar behavior among various ferromagnets and this behavior is expected from a conventional Boltzmann transport theory

  20. Anomalous Hall effect and Nernst effect in itinerant ferromagnets

    International Nuclear Information System (INIS)

    Miyasato, T.; Abe, N.; Fujii, T.; Asamitsu, A.; Onose, Y.; Onoda, S.; Nagaosa, N.; Tokura, Y.

    2007-01-01

    Anomalous Hall effect (AHE) and anomalous Nernst effect (ANE) in many ferromagnetic metals including pure metals, oxides, and chalcogenides, are studied to obtain unified understandings of their origins. We show the universal behavior of anomalous Hall conductivity σ xy as a function of longitudinal conductivity σ xx over six orders of magnitude, which is well reproduced by a recent theory assuming both the intrinsic and extrinsic contributions to the AHE. ANE is closely related with AHE and gives us further information about the electronic state in the ground state of ferromagnets. The temperature dependence of transverse Peltier coefficient α xy shows almost similar behavior among various ferromagnets, and this behavior is expected from a conventional Boltzmann transport theory

  1. A Study to Identify the Transitional Training Needs for United States Army Medical Residents

    Science.gov (United States)

    1988-07-29

    Books Kotler , Philip, and Roberta Clarke. Marketing for Health Care Organizations. Englewood Cliffs: Prentice Hall, 1987. Runyon, Richard P., and...8217 and most can benefit from instruction in administrative principles and practices during residency" (444). A focus began to turn toward residency...leadership development, office communi-ations, professional and legal obligations, Rawls 8 and practice marketing . Because these newly trained physicians

  2. Work-Related Quality of Life among Medical Residents at a University Hospital in Northeastern Thailand.

    Science.gov (United States)

    Somsila, Nattamon; Chaiear, Naesinee; Boonjaraspinyo, Sirintip; Tiamkao, Somsak

    2015-12-01

    1) To assess work-related quality of life (WRQOL) among medical residents at a university hospital in northeast Thailand. 2) To determine the strength of the association between personal and working condition components and WRQOL among medical residents. A descriptive study was used to describe the WRQOL among medical residents. The study population comprised of all 375 residents affiliated with the university hospital. The Thai version of a self-administered work-related quality of life scale-2 was used for data collection. Testing the reliability revealed a Cronbach's alpha of 0.908. Questionnaires were completed by 259 of 375 (68.3%). The study found that the mean rating by residents for overall WRQOL was 113.8 out of 170 (SD 14.8). Most rated WRQOL as moderate (76.6%). The seven sub-factors were rated as moderate to high for employee engagement and control at work, moderate for home/work interface, general well-being and working conditions, high-moderate for job career satisfaction, and low-moderate for stress at work. Relationships between the personal and working condition components and WRQOL were analyzed using binary logistic regression. Residents in minor specialties had a higher WRQOL than those in major specialties (OR 2.522, 95% CI: 1.37, 4.63). Residents who had less than eight duty shifts/week had a higher WRQOL than those with more than eight duty shifts/week (OR 2.263, 95% CI: 1.16, 4.41). Similarly, residents working with less than 80 hours/week had a higher WRQOL than those working more than 80 hours/week (OR 2.344, 95% CI: 1.17, 4.72). A subgroup analyzes of those working in minor specialties showed the trend that working less than eight shifts/month and working less than 80 hours/week had the potential association with good quality of work-life (QWL). This phenomenon is presented in the subgroup analyses of those working in major specialties. Therefore, working hours and number of shifts might have played important role in contributing good QWL

  3. Knowledge, Attitudes, and Practices of Residents in Patient Training at Tabriz University of Medical Sciences, Northwestern Iran

    Directory of Open Access Journals (Sweden)

    Amirala Aghbali

    2014-05-01

    Full Text Available Introduction: The aim of this study was to assess the knowledge and skill of clinical residents in Tabriz University of Medical Sciences, northwestern Iran, (as the future specialists, as well as their attitudes on the necessity of patient education, and the practice and responsibility of the residents in this field. Methods: Knowledge, attitudes, and practices of a random selection of 380 clinical residents at Tabriz University of Medical Sciences were assessed in 2011 through a comprehensive questionnaire about education. The data were analyzed using SPSS software.Results: There was no significant relationship between the two variables of sex and study period and the knowledge variable during the residency. However, there was a significant positive correlation between knowledge and age variables (P<0.05. The level of knowledge rose with aging because the amount of the model significance was less than0.05. Besides, the coefficient of sex was positive by regression analysis. There was no significant relationship between the previous variables and attitude variable. No significant relationship was seen between the previ¬ous variables and practice variable. Conclusion: The influence of age, sex, and year of study was apparent in the knowledge of the residents, but no considerable influence was shown in their practices and attitudes. Some educational strategies are needed to improve the practices and attitudes of the training group.

  4. Scanning vector Hall probe microscopy

    International Nuclear Information System (INIS)

    Cambel, V.; Gregusova, D.; Fedor, J.; Kudela, R.; Bending, S.J.

    2004-01-01

    We have developed a scanning vector Hall probe microscope for mapping magnetic field vector over magnetic samples. The microscope is based on a micromachined Hall sensor and the cryostat with scanning system. The vector Hall sensor active area is ∼5x5 μm 2 . It is realized by patterning three Hall probes on the tilted faces of GaAs pyramids. Data from these 'tilted' Hall probes are used to reconstruct the full magnetic field vector. The scanning area of the microscope is 5x5 mm 2 , space resolution 2.5 μm, field resolution ∼1 μT Hz -1/2 at temperatures 10-300 K

  5. Chapin Hall Center for Children Projects and Publications, 2001-2002.

    Science.gov (United States)

    Chicago Univ., IL. Chapin Hall Center for Children.

    This guide chronicles the ongoing work and writings of the Chapin Hall Center for children at the University of Chicago, a policy research center dedicated to bringing sound information, rigorous analyses, innovative ideas, and an independent, multidisciplinary perspective to bear on policies and programs affecting children. The guide, organized…

  6. Chapin Hall Center for Children Projects and Publications, 2000-2001.

    Science.gov (United States)

    Chicago Univ., IL. Chapin Hall Center for Children.

    This guide chronicles the ongoing work and writings of the Chapin Hall Center for Children at the University of Chicago, a policy research center dedicated to bringing sound information, rigorous analyses, innovative ideas, and an independent, multidisciplinary perspective to bear on policies and programs affecting children. This guide, organized…

  7. Radioactivity and chromosome aberrations of residents of Misasa Spa

    International Nuclear Information System (INIS)

    Morinaga, Hiroshi; Mifune, Masaaki; Furuno, Katsushi

    1985-01-01

    Misasa Spa is one of the most highly radioactive hot springs in Japan, the waters of which contain mainly 222 Rn (437 ± 132 Bq/liter). Radon contents of indoor air of private houses and health resort hotels (built of wood) at Misasa Spa range from 18.5 to 55.5 mBq/liter and 22.2 to 129.5 mBq/liter, respectively. Radon contents in the air of facilities using spring waters at Misasa Branch Hospital of Okayama University were measured to be; bathroom 807 ± 78 mBq/liter; Hubbardtank bathroom 5306 ± 2568 mBq/liter; the drinking hall 1491 ± 178 mBq/liter. The environmental and dose rate inside private house's has been measured to be 14.0 ± 1.8 μR/h. Chromosome aberrations (dicentrics) in the peripheral blood lymphocytes of residents of Misasa Spa were investigated in 14 persons; the mean value of aberration frequencies were 0.21 %. (Kubozono, M.)

  8. High-speed Internet Use and Academic Gratifications in the College Residence.

    Science.gov (United States)

    Matthews, Denise; Schrum, Lynne

    2003-01-01

    A multimethod exploration of undergraduates' high-speed Internet use in residence halls took a uses-and-gratifications approach and revealed Internet use as integral to students' lives. Students' negative comments about Internet distractions from academic work led to identification of an individual difference variable, internal locus of control of…

  9. Superconducting Materials Applied to EP Systems: Applications of Superconductivity to Hall Thrusters Propulsion

    National Research Council Canada - National Science Library

    Bruno, Claudio

    2001-01-01

    This report results from a contract tasking University of Rome as follows: The contractor will investigate the use of superconducting materials for use in high power hall effect type electric propulsion motors...

  10. AdS/QHE: towards a holographic description of quantum Hall experiments

    International Nuclear Information System (INIS)

    Bayntun, Allan; Burgess, C P; Lee, Sung-Sik; Dolan, Brian P

    2011-01-01

    Transitions among quantum Hall plateaux share a suite of remarkable experimental features, such as semicircle laws and duality relations, whose accuracy and robustness are difficult to explain directly in terms of the detailed dynamics of the microscopic electrons. They would naturally follow if the low-energy transport properties were governed by an emergent discrete duality group relating the different plateaux, but no explicit examples of interacting systems having such a group are known. Recent progress using the AdS/CFT correspondence has identified examples with similar duality groups, but without the dc ohmic conductivity characteristic of quantum Hall experiments. We use this to propose a simple holographic model for low-energy quantum Hall systems, with a nonzero dc conductivity that automatically exhibits all of the observed consequences of duality, including the existence of the plateaux and the semicircle transitions between them. The model can be regarded as a strongly coupled analogue of the old 'composite boson' picture of quantum Hall systems. Non-universal features of the model can be used to test whether it describes actual materials, and we comment on some of these in our proposed model. In particular, the model indicates the value 2/5 for low-temperature scaling exponents for transitions among quantum Hall plateaux, in agreement with the measured value 0.42±0.01.

  11. Immunization status of residents in pediatrics at the Federal University of São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Mariana Bernardi Viviani Silveira

    2011-04-01

    Full Text Available Vaccination of health care workers is an efficient way to reduce the risk of occupational infection and to prevent nosocomial transmission to vulnerable patients. Despite this, achieving high immunization rates among those professionals is a challenge. We assessed the immunization status of Residents in Pediatrics at the Federal University of São Paulo from June to December 2008. Their immunization records were checked and evaluated according to the Brazilian Immunization Schedule for health care workers. Considering all required vaccines, only 3.1% of the 64 Residents were up-to-date with their immunizations. Influenza was the vaccine with the lowest uptake (3.1% and measles and rubella were diseases with the highest evidence of immunity (62.5% each. Only 37.5% of Residents had received three hepatitis B vaccine doses with a subsequent serology confirming seroconversion. Moreover, the vast majority of Residents in Pediatrics who were not up-to-date were unaware of the fact. Both medical schools and Pediatric Residence programs should not only offer information but also check vaccination records in an effort to keep their healthcare workers´ vaccinations up-to-date.

  12. Formerly utilized MED/AEC sites Remedial Action Program. Report of the decontamination of Jones Chemical Laboratory, Ryerson Physical Laboratory, and Eckhart Hall, the University of Chicago, Chicago, Illinois

    Energy Technology Data Exchange (ETDEWEB)

    Wynuveen, R.A.; Smith, W.H.; Sholeen, C.M.; Flynn, K.F.

    1984-08-01

    The US Department of Energy (DOE) has implemented a program to decontaminate radioactively contaminated sites that were formerly utilized by the Manhattan Engineer District (MED) and/or the Atomic Energy Commission (AEC) for activities that included handling of radioactive material. This program is referred to as the ''Formerly Utilized Sites Remedial Action Program'' (FUSRAP). Among these sites are Jones Chemical Laboratory, Ryerson Physical Laboratory, Kent Chemical Laboratory, and Eckhart Hall of The University of Chicago, Chicago, Illinois. Since 1977, the University of Chicago decontaminated Kent Chemical Laboratory as part of a facilities renovation program. All areas of Eckhart Hall, Ryerson Physical Laboratory, and Jones Chemical Laboratory that had been identified as contaminated in excess of current guidelines in the 1976-1977 surveys were decontaminated to levels where no contamination could be detected relative to natural backgrounds. All areas that required defacing to achieve this goal were restored to their original condition. The radiological evaluation of the sewer system, based primarily on the radiochemical analyses of sludge and water samples, indicated that the entire sewer system is potentially contaminated. While this evaluation was defined as part of this project, the decontamination of the sewer system was not included in the purview of this effort. The documentation included in this report substantiates the judgment that all contaminated areas identified in the earlier reports in the three structures included in the decontamination effort (Eckhart Hall, Ryerson Physical Laboratory, and Jones Chemical Laboratory) were cleaned to levels commensurate with release for unrestricted use.

  13. Formerly utilized MED/AEC sites Remedial Action Program. Report of the decontamination of Jones Chemical Laboratory, Ryerson Physical Laboratory, and Eckhart Hall, the University of Chicago, Chicago, Illinois

    International Nuclear Information System (INIS)

    Wynuveen, R.A.; Smith, W.H.; Sholeen, C.M.; Flynn, K.F.

    1984-08-01

    The US Department of Energy (DOE) has implemented a program to decontaminate radioactively contaminated sites that were formerly utilized by the Manhattan Engineer District (MED) and/or the Atomic Energy Commission (AEC) for activities that included handling of radioactive material. This program is referred to as the ''Formerly Utilized Sites Remedial Action Program'' (FUSRAP). Among these sites are Jones Chemical Laboratory, Ryerson Physical Laboratory, Kent Chemical Laboratory, and Eckhart Hall of The University of Chicago, Chicago, Illinois. Since 1977, the University of Chicago decontaminated Kent Chemical Laboratory as part of a facilities renovation program. All areas of Eckhart Hall, Ryerson Physical Laboratory, and Jones Chemical Laboratory that had been identified as contaminated in excess of current guidelines in the 1976-1977 surveys were decontaminated to levels where no contamination could be detected relative to natural backgrounds. All areas that required defacing to achieve this goal were restored to their original condition. The radiological evaluation of the sewer system, based primarily on the radiochemical analyses of sludge and water samples, indicated that the entire sewer system is potentially contaminated. While this evaluation was defined as part of this project, the decontamination of the sewer system was not included in the purview of this effort. The documentation included in this report substantiates the judgment that all contaminated areas identified in the earlier reports in the three structures included in the decontamination effort (Eckhart Hall, Ryerson Physical Laboratory, and Jones Chemical Laboratory) were cleaned to levels commensurate with release for unrestricted use

  14. Incorporating resident research into the dermatology residency program

    Science.gov (United States)

    Wagner, Richard F; Raimer, Sharon S; Kelly, Brent C

    2013-01-01

    Programmatic changes for the dermatology residency program at The University of Texas Medical Branch were first introduced in 2005, with the faculty goal incorporating formal dermatology research projects into the 3-year postgraduate training period. This curriculum initially developed as a recommendation for voluntary scholarly project activity by residents, but it evolved into a program requirement for all residents in 2009. Departmental support for this activity includes assignment of a faculty mentor with similar interest about the research topic, financial support from the department for needed supplies, materials, and statistical consultation with the Office of Biostatistics for study design and data analysis, a 2-week elective that provides protected time from clinical activities for the purpose of preparing research for publication and submission to a peer-reviewed medical journal, and a departmental award in recognition for the best resident scholarly project each year. Since the inception of this program, five classes have graduated a total of 16 residents. Ten residents submitted their research studies for peer review and published their scholarly projects in seven dermatology journals through the current academic year. These articles included three prospective investigations, three surveys, one article related to dermatology education, one retrospective chart review, one case series, and one article about dermatopathology. An additional article from a 2012 graduate about dermatology education has also been submitted to a journal. This new program for residents was adapted from our historically successful Dermatology Honors Research Program for medical students at The University of Texas Medical Branch. Our experience with this academic initiative to promote dermatology research by residents is outlined. It is recommended that additional residency programs should consider adopting similar research programs to enrich resident education. PMID:23901305

  15. Incorporating resident research into the dermatology residency program.

    Science.gov (United States)

    Wagner, Richard F; Raimer, Sharon S; Kelly, Brent C

    2013-01-01

    Programmatic changes for the dermatology residency program at The University of Texas Medical Branch were first introduced in 2005, with the faculty goal incorporating formal dermatology research projects into the 3-year postgraduate training period. This curriculum initially developed as a recommendation for voluntary scholarly project activity by residents, but it evolved into a program requirement for all residents in 2009. Departmental support for this activity includes assignment of a faculty mentor with similar interest about the research topic, financial support from the department for needed supplies, materials, and statistical consultation with the Office of Biostatistics for study design and data analysis, a 2-week elective that provides protected time from clinical activities for the purpose of preparing research for publication and submission to a peer-reviewed medical journal, and a departmental award in recognition for the best resident scholarly project each year. Since the inception of this program, five classes have graduated a total of 16 residents. Ten residents submitted their research studies for peer review and published their scholarly projects in seven dermatology journals through the current academic year. These articles included three prospective investigations, three surveys, one article related to dermatology education, one retrospective chart review, one case series, and one article about dermatopathology. An additional article from a 2012 graduate about dermatology education has also been submitted to a journal. This new program for residents was adapted from our historically successful Dermatology Honors Research Program for medical students at The University of Texas Medical Branch. Our experience with this academic initiative to promote dermatology research by residents is outlined. It is recommended that additional residency programs should consider adopting similar research programs to enrich resident education.

  16. Not your grandfather's concert hall

    Science.gov (United States)

    Cooper, Russell; Malenka, Richard; Griffith, Charles; Friedlander, Steven

    2004-05-01

    The opening of Judy and Arthur Zankel Hall on 12 September 2003, restores Andrew Carnegie's original 1891 concept of having three outstanding auditoriums of different sizes under one roof, and creates a 21st-century venue for music performance and education. With concerts ranging from early music to avant-garde multimedia productions, from jazz to world music, and from solo recitals to chamber music, Zankel Hall expands the breadth and depth of Carnegie Hall's offerings. It allows for the integration of programming across three halls with minifestivals tailored both to the size and strengths of each hall and to the artists and music to be performed. The new flexible space also provides Carnegie Hall with an education center equipped with advanced communications technology. This paper discusses the unique program planned for this facility and how the architects, theatre consultants, and acousticians developed a design that fulfilled the client's expectations and coordinated the construction of the facility under the floor of the main Isaac Stern Auditorium without having to cancel a single performance.

  17. A programmable quantum current standard from the Josephson and the quantum Hall effects

    Energy Technology Data Exchange (ETDEWEB)

    Poirier, W., E-mail: wilfrid.poirier@lne.fr; Lafont, F.; Djordjevic, S.; Schopfer, F.; Devoille, L. [Quantum metrology group, Laboratoire National de métrologie et d' Essais, 29 avenue Roger Hennequin, 78197 Trappes (France)

    2014-01-28

    We propose a way to realize a programmable quantum current standard (PQCS) from the Josephson voltage standard and the quantum Hall resistance standard (QHR) exploiting the multiple connection technique provided by the quantum Hall effect (QHE) and the exactness of the cryogenic current comparator. The PQCS could lead to breakthroughs in electrical metrology like the realization of a programmable quantum current source, a quantum ampere-meter, and a simplified closure of the quantum metrological triangle. Moreover, very accurate universality tests of the QHE could be performed by comparing PQCS based on different QHRs.

  18. Debt management and financial planning support for primary care students and residents at Boston University School of Medicine.

    Science.gov (United States)

    Terrell, C; Hindle, D

    1999-01-01

    Boston University Medical Center created the Office of Residency Planning and Practice Management as part of The Robert Wood Johnson Foundation's Generalist Physician Initiative. Since 1995, the office has improved the medical center's ability to promote and support the generalist career decisions of its students and residents by removing indebtedness as a disincentive. After a brief review of the relationship between indebtedness and specialty selection, the authors delineate the nature and volume of debt-management assistance provided by the office to students and residents through individual counseling sessions, workshops, and other means between April 1995 and March 1998. A case study shows the progression of these services throughout residency training. The medical center also coordinates its debt-management assistance with counseling from physician-oriented financial planning groups. In conclusion, the authors discuss several characteristics of a successful debt-management program for residents.

  19. Report of experimental hall subworking group

    International Nuclear Information System (INIS)

    Miyake, K.; Ohama, T.; Takahashi, K.

    1982-01-01

    The general plan of constructing the TRISTAN e + e - colliding beam experimental halls may be divided into two parts. The first step is to construct two test-experimental halls associated with the 6.5 GeV x 6.5 GeV e + e - accumulator ring, and the second step is to build four experimental halls at the 30 GeV x 30 GeV e + e - TRISTAN main ring. At this workshop, extensive discussions on the detailed design of the four main ring experimental halls have been made. Four experimental areas will be built at the main ring, and two test-experimental halls at the accumulating ring. Among the four areas at the main ring, two will be used for electron-proton possible as well as electron-positron colliding beam experiment. The other two will be used exclusively for e + e - colliding experiments. Only a preliminary design has been made for these four experimental areas. A tentative plan of a larger experimental hall includes a counting and data processing room, a utility room, and a radiation safety control room. Two smaller halls have simpler structure. The figures of the experimental halls are presented. The two test-experimental halls at the accumulator ring will be used to test the detectors for e + e - colliding experiments before the final installation. The utility rooms designed for the halls are used to supply coolant and electric power of superconducting magnets. At the workshop, various ideas concerning the preliminary plan are presented. (Kato, T.)

  20. 75 FR 7467 - Gary E. Hall and Rita C. Hall; Notice of Application Accepted for Filing With the Commision...

    Science.gov (United States)

    2010-02-19

    ... Rita C. Hall; Notice of Application Accepted for Filing With the Commision, Soliciting Motions To.... Project No.: 13652-000. c. Date filed: January 11, 2010. d. Applicant: Gary E. Hall and Rita C. Hall. e... Policies Act of 1978, 16 U.S.C. 2705, 2708. h. Applicant Contact: Mr. Gary E. Hall and Ms. Rita C. Hall, P...

  1. Hall Effect Gyrators and Circulators

    Science.gov (United States)

    Viola, Giovanni; DiVincenzo, David P.

    2014-04-01

    The electronic circulator and its close relative the gyrator are invaluable tools for noise management and signal routing in the current generation of low-temperature microwave systems for the implementation of new quantum technologies. The current implementation of these devices using the Faraday effect is satisfactory but requires a bulky structure whose physical dimension is close to the microwave wavelength employed. The Hall effect is an alternative nonreciprocal effect that can also be used to produce desired device functionality. We review earlier efforts to use an Ohmically contacted four-terminal Hall bar, explaining why this approach leads to unacceptably high device loss. We find that capacitive coupling to such a Hall conductor has much greater promise for achieving good circulator and gyrator functionality. We formulate a classical Ohm-Hall analysis for calculating the properties of such a device, and show how this classical theory simplifies remarkably in the limiting case of the Hall angle approaching 90°. In this limit, we find that either a four-terminal or a three-terminal capacitive device can give excellent circulator behavior, with device dimensions far smaller than the ac wavelength. An experiment is proposed to achieve GHz-band gyration in millimeter (and smaller) scale structures employing either semiconductor heterostructure or graphene Hall conductors. An inductively coupled scheme for realizing a Hall gyrator is also analyzed.

  2. Applying Expectancy Theory to residency training: proposing opportunities to understand resident motivation and enhance residency training

    Directory of Open Access Journals (Sweden)

    Shweiki E

    2015-04-01

    Full Text Available Ehyal Shweiki,1 Niels D Martin,2 Alec C Beekley,1 Jay S Jenoff,1 George J Koenig,1 Kris R Kaulback,1 Gary A Lindenbaum,1 Pankaj H Patel,1 Matthew M Rosen,1 Michael S Weinstein,1 Muhammad H Zubair,2 Murray J Cohen1 1Department of Surgery, Thomas Jefferson University Hospital, Philadelphia, PA, USA; 2Department of Surgery, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA Abstract: Medical resident education in the United States has been a matter of national priority for decades, exemplified initially through the Liaison Committee for Graduate Medical Education and then superseded by the Accreditation Council for Graduate Medical Education. A recent Special Report in the New England Journal of Medicine, however, has described resident educational programs to date as prescriptive, noting an absence of innovation in education. Current aims of contemporary medical resident education are thus being directed at ensuring quality in learning as well as in patient care. Achievement and work-motivation theories attempt to explain people's choice, performance, and persistence in tasks. Expectancy Theory as one such theory was reviewed in detail, appearing particularly applicable to surgical residency training. Correlations between Expectancy Theory as a work-motivation theory and residency education were explored. Understanding achievement and work-motivation theories affords an opportunity to gain insight into resident motivation in training. The application of Expectancy Theory in particular provides an innovative perspective into residency education. Afforded are opportunities to promote the development of programmatic methods facilitating surgical resident motivation in education. Keywords: learning, education, achievement

  3. Use of a Behavioral Contract with Resident Assistants: Prelude to a Health Fair.

    Science.gov (United States)

    Morgan, John D.; Hyner, Gerald C.

    1984-01-01

    Presents a conceptual model which focuses on goals of student government in residence halls. The model has two fundamental processes. One focuses on short term goals and activities catering to creation of environment. The second has long term effects referred to as lifelong personal development. (JAC)

  4. Spin Hall effects

    Science.gov (United States)

    Sinova, Jairo; Valenzuela, Sergio O.; Wunderlich, J.; Back, C. H.; Jungwirth, T.

    2015-10-01

    Spin Hall effects are a collection of relativistic spin-orbit coupling phenomena in which electrical currents can generate transverse spin currents and vice versa. Despite being observed only a decade ago, these effects are already ubiquitous within spintronics, as standard spin-current generators and detectors. Here the theoretical and experimental results that have established this subfield of spintronics are reviewed. The focus is on the results that have converged to give us the current understanding of the phenomena, which has evolved from a qualitative to a more quantitative measurement of spin currents and their associated spin accumulation. Within the experimental framework, optical-, transport-, and magnetization-dynamics-based measurements are reviewed and linked to both phenomenological and microscopic theories of the effect. Within the theoretical framework, the basic mechanisms in both the extrinsic and intrinsic regimes are reviewed, which are linked to the mechanisms present in their closely related phenomenon in ferromagnets, the anomalous Hall effect. Also reviewed is the connection to the phenomenological treatment based on spin-diffusion equations applicable to certain regimes, as well as the spin-pumping theory of spin generation used in many measurements of the spin Hall angle. A further connection to the spin-current-generating spin Hall effect to the inverse spin galvanic effect is given, in which an electrical current induces a nonequilibrium spin polarization. This effect often accompanies the spin Hall effect since they share common microscopic origins. Both can exhibit the same symmetries when present in structures comprising ferromagnetic and nonmagnetic layers through their induced current-driven spin torques or induced voltages. Although a short chronological overview of the evolution of the spin Hall effect field and the resolution of some early controversies is given, the main body of this review is structured from a pedagogical

  5. Topological honeycomb magnon Hall effect: A calculation of thermal Hall conductivity of magnetic spin excitations

    Energy Technology Data Exchange (ETDEWEB)

    Owerre, S. A., E-mail: solomon@aims.ac.za [African Institute for Mathematical Sciences, 6 Melrose Road, Muizenberg, Cape Town 7945, South Africa and Perimeter Institute for Theoretical Physics, 31 Caroline St. N., Waterloo, Ontario N2L 2Y5 (Canada)

    2016-07-28

    Quite recently, the magnon Hall effect of spin excitations has been observed experimentally on the kagome and pyrochlore lattices. The thermal Hall conductivity κ{sup xy} changes sign as a function of magnetic field or temperature on the kagome lattice, and κ{sup xy} changes sign upon reversing the sign of the magnetic field on the pyrochlore lattice. Motivated by these recent exciting experimental observations, we theoretically propose a simple realization of the magnon Hall effect in a two-band model on the honeycomb lattice. The magnon Hall effect of spin excitations arises in the usual way via the breaking of inversion symmetry of the lattice, however, by a next-nearest-neighbour Dzyaloshinsky-Moriya interaction. We find that κ{sup xy} has a fixed sign for all parameter regimes considered. These results are in contrast to the Lieb, kagome, and pyrochlore lattices. We further show that the low-temperature dependence on the magnon Hall conductivity follows a T{sup 2} law, as opposed to the kagome and pyrochlore lattices. These results suggest an experimental procedure to measure thermal Hall conductivity within a class of 2D honeycomb quantum magnets and ultracold atoms trapped in a honeycomb optical lattice.

  6. Tunneling Anomalous and Spin Hall Effects.

    Science.gov (United States)

    Matos-Abiague, A; Fabian, J

    2015-07-31

    We predict, theoretically, the existence of the anomalous Hall effect when a tunneling current flows through a tunnel junction in which only one of the electrodes is magnetic. The interfacial spin-orbit coupling present in the barrier region induces a spin-dependent momentum filtering in the directions perpendicular to the tunneling current, resulting in a skew tunneling even in the absence of impurities. This produces an anomalous Hall conductance and spin Hall currents in the nonmagnetic electrode when a bias voltage is applied across the tunneling heterojunction. If the barrier is composed of a noncentrosymmetric material, the anomalous Hall conductance and spin Hall currents become anisotropic with respect to both the magnetization and crystallographic directions, allowing us to separate this interfacial phenomenon from the bulk anomalous and spin Hall contributions. The proposed effect should be useful for proving and quantifying the interfacial spin-orbit fields in metallic and metal-semiconductor systems.

  7. Quantum hall effect. A perspective

    International Nuclear Information System (INIS)

    Aoki, Hideo

    2006-01-01

    Novel concepts and phenomena are emerging recently in the physics of quantum Hall effect. This article gives an overview, which starts from the fractional quantum Hall system viewed as an extremely strongly correlated system, and move on to present various phenomena involving internal degrees of freedom (spin and layer), non-equilibrium and optical properties, and finally the spinoff to anomalous Hall effect and the rotating Bose-Einstein condensate. (author)

  8. Planar Hall effect bridge magnetic field sensors

    DEFF Research Database (Denmark)

    Henriksen, A.D.; Dalslet, Bjarke Thomas; Skieller, D.H.

    2010-01-01

    Until now, the planar Hall effect has been studied in samples with cross-shaped Hall geometry. We demonstrate theoretically and experimentally that the planar Hall effect can be observed for an exchange-biased ferromagnetic material in a Wheatstone bridge topology and that the sensor signal can...... Hall effect bridge sensors....

  9. Hall viscosity of hierarchical quantum Hall states

    Science.gov (United States)

    Fremling, M.; Hansson, T. H.; Suorsa, J.

    2014-03-01

    Using methods based on conformal field theory, we construct model wave functions on a torus with arbitrary flat metric for all chiral states in the abelian quantum Hall hierarchy. These functions have no variational parameters, and they transform under the modular group in the same way as the multicomponent generalizations of the Laughlin wave functions. Assuming the absence of Berry phases upon adiabatic variations of the modular parameter τ, we calculate the quantum Hall viscosity and find it to be in agreement with the formula, given by Read, which relates the viscosity to the average orbital spin of the electrons. For the filling factor ν =2/5 Jain state, which is at the second level in the hierarchy, we compare our model wave function with the numerically obtained ground state of the Coulomb interaction Hamiltonian in the lowest Landau level, and find very good agreement in a large region of the complex τ plane. For the same example, we also numerically compute the Hall viscosity and find good agreement with the analytical result for both the model wave function and the numerically obtained Coulomb wave function. We argue that this supports the notion of a generalized plasma analogy that would ensure that wave functions obtained using the conformal field theory methods do not acquire Berry phases upon adiabatic evolution.

  10. Spin Hall effect by surface roughness

    KAUST Repository

    Zhou, Lingjun

    2015-01-08

    The spin Hall and its inverse effects, driven by the spin orbit interaction, provide an interconversion mechanism between spin and charge currents. Since the spin Hall effect generates and manipulates spin current electrically, to achieve a large effect is becoming an important topic in both academia and industries. So far, materials with heavy elements carrying a strong spin orbit interaction, provide the only option. We propose here a new mechanism, using the surface roughness in ultrathin films, to enhance the spin Hall effect without heavy elements. Our analysis based on Cu and Al thin films suggests that surface roughness is capable of driving a spin Hall angle that is comparable to that in bulk Au. We also demonstrate that the spin Hall effect induced by surface roughness subscribes only to the side-jump contribution but not the skew scattering. The paradigm proposed in this paper provides the second, not if only, alternative to generate a sizable spin Hall effect.

  11. Gauge invariance and fractional quantized Hall effect

    International Nuclear Information System (INIS)

    Tao, R.; Wu, Y.S.

    1984-01-01

    It is shown that gauge invariance arguments imply the possibility of fractional quantized Hall effect; the Hall conductance is accurately quantized to a rational value. The ground state of a system showing the fractional quantized Hall effect must be degenerate; the non-degenerate ground state can only produce the integral quantized Hall effect. 12 references

  12. Nondestructive hall coefficient measurements using ACPD techniques

    Science.gov (United States)

    Velicheti, Dheeraj; Nagy, Peter B.; Hassan, Waled

    2018-04-01

    Hall coefficient measurements offer great opportunities as well as major challenges for nondestructive materials characterization. The Hall effect is produced by the magnetic Lorentz force acting on moving charge carriers in the presence of an applied magnetic field. The magnetic perturbation gives rise to a Hall current that is normal to the conduction current but does not directly perturb the electric potential distribution. Therefore, Hall coefficient measurements usually exploit the so-called transverse galvanomagnetic potential drop effect that arises when the Hall current is intercepted by the boundaries of the specimen and thereby produce a measurable potential drop. In contrast, no Hall potential is produced in a large plate in the presence of a uniform normal field at quasi-static low frequencies. In other words, conventional Hall coefficient measurements are inherently destructive since they require cutting the material under tests. This study investigated the feasibility of using alternating current potential drop (ACPD) techniques for nondestructive Hall coefficient measurements in plates. Specifically, the directional four-point square-electrode configuration is investigated with superimposed external magnetic field. Two methods are suggested to make Hall coefficient measurements in large plates without destructive machining. At low frequencies, constraining the bias magnetic field can replace constraining the dimensions of the specimen, which is inherently destructive. For example, when a cylindrical permanent magnet is used to provide the bias magnetic field, the peak Hall voltage is produced when the diameter of the magnet is equal to the diagonal of the square ACPD probe. Although this method is less effective than cutting the specimen to a finite size, the loss of sensitivity is less than one order of magnitude even at very low frequencies. In contrast, at sufficiently high inspection frequencies the magnetic field of the Hall current induces a

  13. What the Building Boom Says about Campus Values

    Science.gov (United States)

    Bonfiglio, Robert A.

    2004-01-01

    Some construction projects that colleges and universities have recently undertaken--residence halls, dining halls, student centers, athletic and recreation centers--have attracted significant criticism. Critics have taken issue with the proliferation and design of buildings intended to structure the use of students' free time and attract…

  14. Scaling relation of the anomalous Hall effect in (Ga,Mn)As

    Science.gov (United States)

    Glunk, M.; Daeubler, J.; Schoch, W.; Sauer, R.; Limmer, W.

    2009-09-01

    We present magnetotransport studies performed on an extended set of (Ga,Mn)As samples at 4.2 K with longitudinal conductivities σxx ranging from the low-conductivity to the high-conductivity regime. The anomalous Hall conductivity σxy(AH) is extracted from the measured longitudinal and Hall resistivities. A transition from σxy(AH)=20Ω-1cm-1 due to the Berry phase effect in the high-conductivity regime to a scaling relation σxy(AH)∝σxx1.6 for low-conductivity samples is observed. This scaling relation is consistent with a recently developed unified theory of the anomalous Hall effect in the framework of the Keldysh formalism. It turns out to be independent of crystallographic orientation, growth conditions, Mn concentration, and strain, and can therefore be considered universal for low-conductivity (Ga,Mn)As. The relation plays a crucial role when deriving values of the hole concentration from magnetotransport measurements in low-conductivity (Ga,Mn)As. In addition, the hole diffusion constants for the high-conductivity samples are determined from the measured longitudinal conductivities.

  15. Topologically induced fractional Hall steps in the integer quantum Hall regime of MoS 2

    Science.gov (United States)

    Firoz Islam, SK; Benjamin, Colin

    2016-09-01

    The quantum magnetotransport properties of a monolayer of molybdenum disulfide are derived using linear response theory. In particular, the effect of topological terms on longitudinal and Hall conductivity is analyzed. The Hall conductivity exhibits fractional steps in the integer quantum Hall regime. Further complete spin and valley polarization of the longitudinal conductivitity is seen in presence of these topological terms. Finally, the Shubnikov-de Hass oscillations are suppressed or enhanced contingent on the sign of these topological terms.

  16. Stephen Hall Receives 2012 Walter Sullivan Award for Excellence in Science Journalism-Features: Citation

    Science.gov (United States)

    Pearson, Helen

    2013-01-01

    Stephen Hall, a freelance science writer and science-communication teacher, received the Walter Sullivan Award for Excellence in Science Journalism-Features at the AGU Fall Meeting Honors Ceremony, held on 5 December 2012 in San Francisco, Calif. Hall was honored for the article "At Fault?" published 15 September 2011 in Nature. The article examines the legal, personal, and political repercussions from a 2009 earthquake in L'Aquila, Italy for seismologists who had attempted to convey seismic risk assessments to the public. The 6.3 magnitude quake devastated the medieval town and caused more than 300 deaths. Six scientists and one government official were subsequently convicted of manslaughter and sentenced to prison for inadequately assessing and mischaracterizing the risks to city residents, despite the inexact nature of seismic risk assessment. The Sullivan award is for work published with a deadline pressure of more than 1 week.

  17. ac spin-Hall effect

    International Nuclear Information System (INIS)

    Entin-Wohlman, O.

    2005-01-01

    Full Text:The spin-Hall effect is described. The Rashba and Dresselhaus spin-orbit interactions are both shown to yield the low temperature spin-Hall effect for strongly localized electrons coupled to phonons. A frequency-dependent electric field E(ω) generates a spin-polarization current, normal to E, due to interference of hopping paths. At zero temperature the corresponding spin-Hall conductivity is real and is proportional to ω 2 . At non-zero temperatures the coupling to the phonons yields an imaginary term proportional to ω. The interference also yields persistent spin currents at thermal equilibrium, at E = 0. The contributions from the Dresselhaus and Rashba interactions to the interference oppose each other

  18. Diagnostics Systems for Permanent Hall Thrusters Development

    Science.gov (United States)

    Ferreira, Jose Leonardo; Soares Ferreira, Ivan; Santos, Jean; Miranda, Rodrigo; Possa, M. Gabriela

    This work describes the development of Permanent Magnet Hall Effect Plasma Thruster (PHALL) and its diagnostic systems at The Plasma Physics Laboratory of University of Brasilia. The project consists on the construction and characterization of plasma propulsion engines based on the Hall Effect. Electric thrusters have been employed in over 220 successful space missions. Two types stand out: the Hall-Effect Thruster (HET) and the Gridded Ion Engine (GIE). The first, which we deal with in this project, has the advantage of greater simplicity of operation, a smaller weight for the propulsion subsystem and a longer shelf life. It can operate in two configurations: magnetic layer and anode layer, the difference between the two lying in the positioning of the anode inside the plasma channel. A Hall-Effect Thruster-HET is a type of plasma thruster in which the propellant gas is ionized and accelerated by a magneto hydrodynamic effect combined with electrostatic ion acceleration. So the essential operating principle of the HET is that it uses a J x B force and an electrostatic potential to accelerate ions up to high speeds. In a HET, the attractive negative charge is provided by electrons at the open end of the Thruster instead of a grid, as in the case of the electrostatic ion thrusters. A strong radial magnetic field is used to hold the electrons in place, with the combination of the magnetic field and the electrostatic potential force generating a fast circulating electron current, the Hall current, around the axis of the Thruster, mainly composed by drifting electrons in an ion plasma background. Only a slow axial drift towards the anode occurs. The main attractive features of the Hall-Effect Thruster are its simple design and operating principles. Most of the Hall-Effect Thrusters use electromagnet coils to produce the main magnetic field responsible for plasma generation and acceleration. In this paper we present a different new concept, a Permanent Magnet Hall

  19. Hořava-Lifshitz gravity and effective theory of the fractional quantum Hall effect

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Chaolun [Kadanoff Center for Theoretical Physics and Enrico Fermi Institute, University of Chicago,Chicago, Illinois 60637 (United States); Wu, Shao-Feng [Department of Physics, Shanghai University,Shanghai 200444 (China); Kadanoff Center for Theoretical Physics and Enrico Fermi Institute, University of Chicago,Chicago, Illinois 60637 (United States)

    2015-01-22

    We show that Hořava-Lifshitz gravity theory can be employed as a covariant framework to build an effective field theory for the fractional quantum Hall effect that respects all the spacetime symmetries such as non-relativistic diffeomorphism invariance and anisotropic Weyl invariance as well as the gauge symmetry. The key to this formalism is a set of correspondence relations that maps all the field degrees of freedom in the Hořava-Lifshitz gravity theory to external background (source) fields among others in the effective action of the quantum Hall effect, according to their symmetry transformation properties. We originally derive the map as a holographic dictionary, but its form is independent of the existence of holographic duality. This paves the way for the application of Hořava-Lifshitz holography on fractional quantum Hall effect. Using the simplest holographic Chern-Simons model, we compute the low energy effective action at leading orders and show that it captures universal electromagnetic and geometric properties of quantum Hall states, including the Wen-Zee shift, Hall viscosity, angular momentum density and their relations. We identify the shift function in Hořava-Lifshitz gravity theory as minus of guiding center velocity and conjugate to guiding center momentum. This enables us to distinguish guiding center angular momentum density from the internal one, which is the sum of Landau orbit spin and intrinsic (topological) spin of the composite particles. Our effective action shows that Hall viscosity is minus half of the internal angular momentum density and proportional to Wen-Zee shift, and Hall bulk viscosity is half of the guiding center angular momentum density.

  20. Hybrid-PIC Computer Simulation of the Plasma and Erosion Processes in Hall Thrusters

    Science.gov (United States)

    Hofer, Richard R.; Katz, Ira; Mikellides, Ioannis G.; Gamero-Castano, Manuel

    2010-01-01

    HPHall software simulates and tracks the time-dependent evolution of the plasma and erosion processes in the discharge chamber and near-field plume of Hall thrusters. HPHall is an axisymmetric solver that employs a hybrid fluid/particle-in-cell (Hybrid-PIC) numerical approach. HPHall, originally developed by MIT in 1998, was upgraded to HPHall-2 by the Polytechnic University of Madrid in 2006. The Jet Propulsion Laboratory has continued the development of HPHall-2 through upgrades to the physical models employed in the code, and the addition of entirely new ones. Primary among these are the inclusion of a three-region electron mobility model that more accurately depicts the cross-field electron transport, and the development of an erosion sub-model that allows for the tracking of the erosion of the discharge chamber wall. The code is being developed to provide NASA science missions with a predictive tool of Hall thruster performance and lifetime that can be used to validate Hall thrusters for missions.

  1. Temporally Adrift and Permanently Liminal: Relations, Dystalgia and a U.S. University as Site of Transition and Frontier

    Directory of Open Access Journals (Sweden)

    Frank G. Karioris

    2016-04-01

    Full Text Available This article seeks to explore temporal reconceptualizations and forms of nostalgia that first-year university men are experiencing and creating. It will explore the ways that time can be conceived of in relation to the present and a future that is not-yet-existent. The article takes as its starting point ethnographic fieldwork in the 21st century at a private, Catholic university in the U.S. and, in particular, men in an all-male residence hall. In focusing on this hall, it means to locate and localize the thinking in the context of the 21st century as well as within the U.S., including ne-oliberalism as a social and economic method of relating. Through the exploration of these men's envisioning of themselves as their future selves and the way they review the self that is now, this article makes a claim that they are - through both their actions, ways of relating, and the societal positioning - multiply liminal. Further, it will explore the way that through this temporal representation they are endowing themselves as permanently liminal both currently and in the future. The article situates these men amidst the university as an institution, as well as seeking to elucidate the importance of this temporal creation as a building of forms of transition and frontier.

  2. Factors that influence utilisation of HIV/AIDS prevention methods among university students residing at a selected university campus.

    Science.gov (United States)

    Ndabarora, Eléazar; Mchunu, Gugu

    2014-01-01

    Various studies have reported that university students, who are mostly young people, rarely use existing HIV/AIDS preventive methods. Although studies have shown that young university students have a high degree of knowledge about HIV/AIDS and HIV modes of transmission, they are still not utilising the existing HIV prevention methods and still engage in risky sexual practices favourable to HIV. Some variables, such as awareness of existing HIV/AIDS prevention methods, have been associated with utilisation of such methods. The study aimed to explore factors that influence use of existing HIV/AIDS prevention methods among university students residing in a selected campus, using the Health Belief Model (HBM) as a theoretical framework. A quantitative research approach and an exploratory-descriptive design were used to describe perceived factors that influence utilisation by university students of HIV/AIDS prevention methods. A total of 335 students completed online and manual questionnaires. Study findings showed that the factors which influenced utilisation of HIV/AIDS prevention methods were mainly determined by awareness of the existing university-based HIV/AIDS prevention strategies. Most utilised prevention methods were voluntary counselling and testing services and free condoms. Perceived susceptibility and perceived threat of HIV/AIDS score was also found to correlate with HIV risk index score. Perceived susceptibility and perceived threat of HIV/AIDS showed correlation with self-efficacy on condoms and their utilisation. Most HBM variables were not predictors of utilisation of HIV/AIDS prevention methods among students. Intervention aiming to improve the utilisation of HIV/AIDS prevention methods among students at the selected university should focus on removing identified barriers, promoting HIV/AIDS prevention services and providing appropriate resources to implement such programmes.

  3. Hall C

    Data.gov (United States)

    Federal Laboratory Consortium — Hall C's initial complement of equipment (shown in the figure), includes two general-purpose magnetic spectrometers. The High Momentum Spectrometer (HMS) has a large...

  4. Hall A

    Data.gov (United States)

    Federal Laboratory Consortium — The instrumentation in Hall A at the Thomas Jefferson National Accelerator Facility was designed to study electroand photo-induced reactions at very high luminosity...

  5. The History of the Austin College Building and Old Main at Sam Houston State University

    Science.gov (United States)

    Singer, Erin; Shields, Samantha

    2017-01-01

    Austin Hall and Old Main serve as the heart of what is now Sam Houston State University. The buildings' rich histories help one to understand how Sam Houston State University and its proud teacher education heritage came to be. To begin with Austin Hall's story, the University's original building has a unique and interesting tale that journeys…

  6. Medical Student Interest in Flexible Residency Training Options.

    Science.gov (United States)

    Piotrowski, Madison; Stulberg, Debra; Egan, Mari

    2018-05-01

    Medical residents continue to experience high rates of burnout during residency training even after implementation of the 2003 Accreditation Council for Graduate Medical Education duty-hour restrictions. The purpose of this study is to determine medical student interest in flexible residency training options. Researchers developed an 11-question survey for second through fourth-year medical students. The populations surveyed included medical students who were: (1) attending the 2015 American Academy of Family Physicians National Conference, the 2015 Family Medicine Midwest Conference, and (2) enrolled at University of Chicago Pritzker School of Medicine, University of Illinois College of Medicine at Chicago, Drexel University College of Medicine, and Case Western Reserve University School of Medicine. The survey was completed by 789 medical students. Over half of medical students surveyed indicated that they would be interested in working part-time during some portion of their residency training (51%), and that access to part-time training options would increase their likelihood of applying to a particular residency program (52%). When given the option of three residency training schedules of varying lengths, 41% of male students and 60% of female students chose a 60-hour workweek, even when that meant extending the residency length by 33% and reducing their yearly salary to $39,000. There is considerable interest among medical students in access to part-time residency training options and reduced-hour residency programs. This level of interest indicates that offering flexible training options could be an effective recruitment tool for residency programs and could improve students' perception of their work-life balance during residency.

  7. Public health risk status of the water supply frame work at Kwame ...

    African Journals Online (AJOL)

    The aim of the study is to assess the public health risk status of the potable water supply framework at the Kwame Nkurumah Postgraduate Residence (PG) Hall, University of Nigeria, Nsukka, (UNN), Enugu State, Nigeria, and environs. Four potable water supply frame-works at the PG Hall, UNN, and exposed stagnant ...

  8. 75 FR 22770 - Gary E. Hall and Rita Hall; Notice of Availability of Environmental Assessment

    Science.gov (United States)

    2010-04-30

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 13652-000-Montana] Gary E. Hall and Rita Hall; Notice of Availability of Environmental Assessment April 22, 2010. In accordance with the National Environmental Policy Act of 1969, as amended, and the Federal Energy Regulatory...

  9. Can changes in psychosocial factors and residency explain the decrease in physical activity during the transition from high school to college or university?

    Science.gov (United States)

    Van Dyck, Delfien; De Bourdeaudhuij, Ilse; Deliens, Tom; Deforche, Benedicte

    2015-04-01

    When students make the transition from high school to college or university, their physical activity (PA) levels decrease strongly. Consequently, it is of crucial importance to identify the determinants of this decline in PA. The study aims were to (1) examine changes in psychosocial factors in students during the transition from high school to college/university, (2) examine if changes in psychosocial factors and residency can predict changes in PA, and (3) investigate the moderating effects of residency on the relationship between changes in psychosocial factors and changes in PA. Between March 2008 and October 2010, 291 Flemish students participated in a longitudinal study, with baseline measurements during the final year of high school and follow-up measurements at the start of second year of college/university. At both time points, participants completed a questionnaire assessing demographics, active transportation, leisure-time sports, psychosocial variables, and residency. Repeated measures MANOVA analyses and multiple moderated hierarchic regression analyses were conducted. Modeling, self-efficacy, competition-related benefits, and health-related, external and social barriers decreased, while health-related benefits and time-related barriers increased from baseline to follow-up. Decreases in modeling and time-related barriers were associated with a decrease in active transportation (adjusted R(2) = 3.2%); residency, decreases in self-efficacy, competition-related benefits, and increases in health- and time-related barriers predicted a decrease in leisure-time sports (adjusted R(2) = 29.3%). Residency only moderated two associations between psychosocial factors and changes in PA. Residency and changes in psychosocial factors were mainly important to explain the decrease in leisure-time sports. Other factors such as distance to college/university are likely more important to explain the decrease in active transportation; these are worth exploring in

  10. Charge carrier coherence and Hall effect in organic semiconductors

    Science.gov (United States)

    Yi, H. T.; Gartstein, Y. N.; Podzorov, V.

    2016-01-01

    Hall effect measurements are important for elucidating the fundamental charge transport mechanisms and intrinsic mobility in organic semiconductors. However, Hall effect studies frequently reveal an unconventional behavior that cannot be readily explained with the simple band-semiconductor Hall effect model. Here, we develop an analytical model of Hall effect in organic field-effect transistors in a regime of coexisting band and hopping carriers. The model, which is supported by the experiments, is based on a partial Hall voltage compensation effect, occurring because hopping carriers respond to the transverse Hall electric field and drift in the direction opposite to the Lorentz force acting on band carriers. We show that this can lead in particular to an underdeveloped Hall effect observed in organic semiconductors with substantial off-diagonal thermal disorder. Our model captures the main features of Hall effect in a variety of organic semiconductors and provides an analytical description of Hall mobility, carrier density and carrier coherence factor. PMID:27025354

  11. Charge carrier coherence and Hall effect in organic semiconductors.

    Science.gov (United States)

    Yi, H T; Gartstein, Y N; Podzorov, V

    2016-03-30

    Hall effect measurements are important for elucidating the fundamental charge transport mechanisms and intrinsic mobility in organic semiconductors. However, Hall effect studies frequently reveal an unconventional behavior that cannot be readily explained with the simple band-semiconductor Hall effect model. Here, we develop an analytical model of Hall effect in organic field-effect transistors in a regime of coexisting band and hopping carriers. The model, which is supported by the experiments, is based on a partial Hall voltage compensation effect, occurring because hopping carriers respond to the transverse Hall electric field and drift in the direction opposite to the Lorentz force acting on band carriers. We show that this can lead in particular to an underdeveloped Hall effect observed in organic semiconductors with substantial off-diagonal thermal disorder. Our model captures the main features of Hall effect in a variety of organic semiconductors and provides an analytical description of Hall mobility, carrier density and carrier coherence factor.

  12. Guild Hall retrofit

    Energy Technology Data Exchange (ETDEWEB)

    1984-08-01

    This report demonstrates the economic viability of an exterior rewrap retrofit performed on a public community facility for the performing arts. This facility originally consisted of two mess halls built by the American army. The exterior retrofit consisted of constructing a super-insulated passageway to link the two halls as well as completely wrapping the facility with six millimetre polyethylene to provide an airtight barrier. The roofs and walls were reinsulated and insulation levels were increased to RSI 10.5 in the ceilings and RSI 7.7 in the walls. The installation of a propane fuelled furnace was also included in the retrofit package. Prior to the renovations and retrofitting, the Guild Hall facility was almost unusable. The demonstration project transformed the cold, drafty buildings into an attractive, comfortable and functional centre for the performing arts. Heating requirements have been reduced to 500 MJ/m {sup 2} of floor space annually compared to a predicted 1,760 MJ/m{sup 2} of floor space based on HOTCAN analysis of the heating requirements without the energy conservation measures. 9 figs., 10 tabs.

  13. Scaling behavior of mixed-state hall effect in MgB2 thin films

    International Nuclear Information System (INIS)

    Jung, Soon-Gil; Seong, W.K.; Kang, W.N.; Choi, Eun-Mi; Kim, Heon-Jung; Lee, Sung-Ik; Kim, Hyeong-Jin; Kim, H.C.

    2006-01-01

    The Hall resistivity (ρ xy ) and the longitudinal resistivity (ρ xx ) in c-axis-oriented superconducting MgB 2 thin films have been investigated in extended fields up to 18T. We have observed a scaling behavior between the Hall resistivity and the longitudinal resistivity, ρ xy =Aρ xx β , where the exponent (β) is observed to be independent of the temperatures and the magnetic fields. For a wide magnetic field region from 1 to 18T and a wide temperature region from 10 to 28K, a universal power law with β=2.0+/-0.1 was observed in c-axis-oriented MgB 2 thin films. These results can be well interpreted by using recent models

  14. Living with students: Lessons learned while pursuing tenure, administration, and raising a family.

    Science.gov (United States)

    Humphrey, Michael; Callahan, Janet; Harrison, Geoff

    2015-01-01

    An emerging promising practice in many universities has been the development of faculty-in-residence programs, in which university faculty members and their family moved into university student residences, sharing common living spaces with students. This case study is centered on two faculty-in-residence living in university residence halls. One was an assistant professor pursuing tenure while raising a young child, while the second was a tenured full professor and associate dean raising two teens. This case study offers the post-experience conclusions of these two faculty-in-residence individuals, noting the benefits and challenges each experienced while living -and working closely with these students outside of the university classroom, all while striving for an optimal balance in managing professional and familial obligations.

  15. Frazier Hall: The foundation failure that didn't

    International Nuclear Information System (INIS)

    Robinson, L.

    1994-01-01

    Frazier Hall is the oldest building on the Idaho State University campus--built before scientific foundation design was common. Its footings were clearly under designed, compared with modern practice. In fact, conventional analysis of the bearing capacity of two footings of this historic building indicate a failure condition. However, this structure is 60 years old and the foundation is still functioning. Possible reasons for the discrepancy between the analysis results and reality are posed and evaluated. This exercise gives some valuable insights into the process of foundation analysis and design. 7 refs., 5 figs

  16. Substance abuse: a national survey of Canadian residency program directors and site chiefs at university-affiliated anesthesia departments.

    Science.gov (United States)

    Boulis, Sherif; Khanduja, P Kristina; Downey, Kristi; Friedman, Zeev

    2015-09-01

    The abuse of substances available to anesthesiologists in their workspace is a potentially lethal occupational hazard. Our primary objective was to define the prevalence of substance abuse cases among Canadian anesthesiologists at university-affiliated hospitals. Our secondary aim was to describe the current management of confirmed cases, rehabilitation procedures being offered, and preventative strategies being employed. We conducted a cross-sectional electronic survey of all Canadian anesthesia residency program directors and site chiefs at university-affiliated hospitals. Data analysis was performed using descriptive statistics. The survey response rate was 54% (53/98). Substance abuse was reported as 1.6% for residents and 0.3% for clinical fellows over a ten-year period ending in June 2014. Fentanyl was abused in nine of 24 reported cases. At present, one of 22 respondents (4.5%) reported a formal education program on substance abuse for faculty members, and 72% described mandatory education for residents. The majority of participants did not perceive substance abuse as a growing problem. Seventy-one percent of respondents indicated that methods for controlled-drug handling had changed in the previous ten years; however, 66% did not think that the incidence of controlled substance abuse could be decreased further by more stringent measures. Only 21% of respondents supported the introduction of random urine drug testing. The prevalence of substance abuse among Canadian anesthesiologists and the substances abused appear comparable with data from the United States, with residents being the group most often affected. Early recognition and treatment of chemically dependent anesthesiologists remain imperfect.

  17. [Work satisfaction, quality of life and leisure time of residents at the Soroka University Medical Center, Beer Sheba, Israel].

    Science.gov (United States)

    Acker, Asaf; Perry, Zvi; Reuveni, Haim; Toker, Asaf

    2009-02-01

    Work dissatisfaction among physicians worldwide continues to rise over the last few decades, mainly due to declining professional prestige, tack of self fulfillment, time pressure and tack of leisure time. Physicians' burnout is a major result of dissatisfaction, causing doctors to leave the medical profession, and to provide lower quality of care. To examine the work satisfaction, quality of life and leisure time of residents in the Soroka University Medical Center. A validated questionnaire was delivered during the second half of 2004 to 252 residents in the Soroka University Medical Center The data was analyzed using the SPSS 12 for windows program. Descriptive analysis, parametric Students' T Test [where pleisure time. Further attention must be given to these matters--a step which will eventually improve patient care, and delay, to some extent, the burnout of physicians.

  18. The Other Hall Effect: College Board Physics

    Science.gov (United States)

    Sheppard, Keith; Gunning, Amanda M.

    2013-01-01

    Edwin Herbert Hall (1855-1938), discoverer of the Hall effect, was one of the first winners of the AAPT Oersted Medal for his contributions to the teaching of physics. While Hall's role in establishing laboratory work in high schools is widely acknowledged, his position as chair of the physics section of the Committee on College Entrance…

  19. Universality of modular symmetries in two-dimensional magnetotransport

    Science.gov (United States)

    Olsen, K. S.; Limseth, H. S.; Lütken, C. A.

    2018-01-01

    We analyze experimental quantum Hall data from a wide range of different materials, including semiconducting heterojunctions, thin films, surface layers, graphene, mercury telluride, bismuth antimonide, and black phosphorus. The fact that these materials have little in common, except that charge transport is effectively two-dimensional, shows how robust and universal the quantum Hall phenomenon is. The scaling and fixed point data we analyzed appear to show that magnetotransport in two dimensions is governed by a small number of universality classes that are classified by modular symmetries, which are infinite discrete symmetries not previously seen in nature. The Hall plateaux are (infrared) stable fixed points of the scaling-flow, and quantum critical points (where the wave function is delocalized) are unstable fixed points of scaling. Modular symmetries are so rigid that they in some cases fix the global geometry of the scaling flow, and therefore predict the exact location of quantum critical points, as well as the shape of flow lines anywhere in the phase diagram. We show that most available experimental quantum Hall scaling data are in good agreement with these predictions.

  20. Anomalous Hall effect in polycrystalline Ni films

    KAUST Repository

    Guo, Zaibing

    2012-02-01

    We systematically studied the anomalous Hall effect in a series of polycrystalline Ni films with thickness ranging from 4 to 200 nm. It is found that both the longitudinal and anomalous Hall resistivity increased greatly as film thickness decreased. This enhancement should be related to the surface scattering. In the ultrathin films (46 nm thick), weak localization corrections to anomalous Hall conductivity were studied. The granular model, taking into account the dominated intergranular tunneling, has been employed to explain this phenomenon, which can explain the weak dependence of anomalous Hall resistivity on longitudinal resistivity as well. © 2011 Elsevier Ltd. All rights reserved.

  1. Elementary theory of quantum Hall effect

    Directory of Open Access Journals (Sweden)

    Keshav N. Shrivastava

    2008-04-01

    Full Text Available The Hall effect is the generation of a current perpendicular to both the direction of the applied electric as well as magnetic field in a metal or in a semiconductor. It is used to determine the concentration of electrons. The quantum Hall effect with integer quantization was discovered by von Klitzing and fractionally charged states were found by Tsui, Stormer and Gossard. Robert Laughlin explained the quantization of Hall current by using “flux quantization” and introduced incompressibility to obtain the fractional charge. We have developed the theory of the quantum Hall effect by using the theory of angular momentum. Our predicted fractions are in accord with those measured. We emphasize our explanation of the observed phenomena. We use spin to explain the fractional charge and hence we discover spin-charge locking.

  2. Temperature dependence of collapse of quantized hall resistance

    International Nuclear Information System (INIS)

    Tanaka, Hiroyasu; Kawashima, Hironori; Iizuka, Hisamitsu; Fukuda, Hideaki; Kawaji, Shinji

    2006-01-01

    Similarity is observed in the deviation of Hall resistance from the quantized value with the increase in the source-drain current I SD in our butterfly-type Hall bars and in the Hall bars used by Jeanneret et al., while changes in the diagonal resistivity ρ xx with I SD are significantly different between these Hall bars. The temperature dependence of the critical Hall electric field F cr (T) for the collapse of R H (4) measured in these Hall bars is approximated using F cr (T) = F cr (0)(1 - (T/T cr ) 2 ). Here, the critical Hall electric field at zero temperature depends on the magnetic field B as F cr (0) ∝ B 3/2 . Theoretical considerations are given on F cr (T) on the basis of a temperature-dependent mobility edge model and a schema of temperature-dependent inter-Landau level tunneling probability arising from the Fermi distribution function. The former does not fit in with the I SD dependence of activation energy in ρ xx . (author)

  3. Prospect of quantum anomalous Hall and quantum spin Hall effect in doped kagome lattice Mott insulators.

    Science.gov (United States)

    Guterding, Daniel; Jeschke, Harald O; Valentí, Roser

    2016-05-17

    Electronic states with non-trivial topology host a number of novel phenomena with potential for revolutionizing information technology. The quantum anomalous Hall effect provides spin-polarized dissipation-free transport of electrons, while the quantum spin Hall effect in combination with superconductivity has been proposed as the basis for realizing decoherence-free quantum computing. We introduce a new strategy for realizing these effects, namely by hole and electron doping kagome lattice Mott insulators through, for instance, chemical substitution. As an example, we apply this new approach to the natural mineral herbertsmithite. We prove the feasibility of the proposed modifications by performing ab-initio density functional theory calculations and demonstrate the occurrence of the predicted effects using realistic models. Our results herald a new family of quantum anomalous Hall and quantum spin Hall insulators at affordable energy/temperature scales based on kagome lattices of transition metal ions.

  4. The quantum hall effect

    International Nuclear Information System (INIS)

    El-Arabi, N. M.

    1993-01-01

    Transport phenomena in two dimensional semiconductors have revealed unusual properties. In this thesis these systems are considered and discussed. The theories explain the Integral Quantum Hall Effect (IQHE) and the Fractional Quantum Hall Effect (FQHE). The thesis is composed of five chapters. The first and the second chapters lay down the theory of the IQHE, the third and fourth consider the theory of the FQHE. Chapter five deals with the statistics of particles in two dimension. (author). Refs

  5. Analysis of Deformations of the Skylight Construction at the Main Hall of the Warsaw University of Technology

    Science.gov (United States)

    Odziemczyk, Waldemar

    2015-02-01

    The paper presents technology and results of measurements of the steel construction of the skylight of the Main Hall of the Warsaw University of Technology. The new version of the automated measuring system has been used for measurements. This system is based on Leica TCRP1201+ total station and the TCcalc1200 software application, developed by the author, which operates on a laptop computer connected with the total station by the wire. Two test measurements were performed. Each of them consisted of cyclic measurement using the polar method, from one station; points located on the skylight construction, as well as control points located on concrete, bearing poles, were successively measured. Besides geometrical values (such as Hz, V angles and the slope distance D), the changes of temperature and atmospheric pressure, were also recorded. Processed results of measurements contained information concerning the behaviour of the skylight; asymmetry of horizontal displacements with respect to the X axis have been proved. Changes of parameters of the instrument telescope and changes of the instrument orientation were also stated; they were connected with changes of the temperature. The most important results of works have been presented in the form of diagrams.

  6. Dr. Hall and the work cure.

    Science.gov (United States)

    Reed, Kathlyn L

    2005-01-01

    Herbert James Hall, MD (1870-1923), was a pioneer in the systematic and organized study of occupation as therapy for persons with nervous and mental disorders that he called the "work cure." He began his work in 1904 during the early years of the Arts and Crafts Movement in the United States. His primary interest was the disorder neurasthenia, a condition with many symptoms including chronic fatigue, stress, and inability to work or perform everyday tasks. The prevailing treatment of the day was absolute bed rest known as the "rest cure." Hall believed that neurasthenia was not caused by overwork but by faulty living habits that could be corrected through an ordered life schedule and selected occupations. He identified several principles of therapy that are still used today including graded activity and energy conservation. Dr. Adolph Meyer credits Hall for organizing the ideas on the therapeutic use of occupation (Meyer, 1922). Hall also provided the name American Occupational Therapy Association for the professional organization and served as the fourth president. For his many contributions to the profession Hall deserves to be recognized as a major contributor to the development and organization of occupational therapy.

  7. Particle-in-cell numerical simulations of a cylindrical Hall thruster with permanent magnets

    Science.gov (United States)

    Miranda, Rodrigo A.; Martins, Alexandre A.; Ferreira, José L.

    2017-10-01

    The cylindrical Hall thruster (CHT) is a propulsion device that offers high propellant utilization and performance at smaller dimensions and lower power levels than traditional Hall thrusters. In this paper we present first results of a numerical model of a CHT. This model solves particle and field dynamics self-consistently using a particle-in-cell approach. We describe a number of techniques applied to reduce the execution time of the numerical simulations. The specific impulse and thrust computed from our simulations are in agreement with laboratory experiments. This simplified model will allow for a detailed analysis of different thruster operational parameters and obtain an optimal configuration to be implemented at the Plasma Physics Laboratory at the University of Brasília.

  8. Does providing nutrition information at vending machines reduce calories per item sold?

    Science.gov (United States)

    Dingman, Deirdre A; Schulz, Mark R; Wyrick, David L; Bibeau, Daniel L; Gupta, Sat N

    2015-02-01

    In 2010, the United States (US) enacted a restaurant menu labeling law. The law also applied to vending machine companies selling food. Research suggested that providing nutrition information on menus in restaurants might reduce the number of calories purchased. We tested the effect of providing nutrition information and 'healthy' designations to consumers where vending machines were located in college residence halls. We conducted our study at one university in Southeast US (October-November 2012). We randomly assigned 18 vending machines locations (residence halls) to an intervention or control group. For the intervention we posted nutrition information, interpretive signage, and sent a promotional email to residents of the hall. For the control group we did nothing. We tracked sales over 4 weeks before and 4 weeks after we introduced the intervention. Our intervention did not change what the residents bought. We recommend additional research about providing nutrition information where vending machines are located, including testing formats used to present information.

  9. Burnout among Dutch medical residents

    NARCIS (Netherlands)

    Prins, J.T.; Hoekstra-Weebers, J.E.; Van De Wiel, H.B.; Gazendam-Donofrio, S.M.; Sprangers, F.; Jaspers, F.C.; van der Heijden, F.M.

    2007-01-01

    We examined levels of burnout and relationships between burnout, gender, age, years in training, and medical specialty in 158 medical residents working at the University Medical Center Groningen, the Netherlands. Thirteen percent of the residents met the criteria for burnout, with the highest

  10. Psychiatry residents in a milieu participatory democracy: a resident's view.

    Science.gov (United States)

    Gersten, D

    1978-11-01

    Psychiatry residents respond with a variety of coping mechanisms to the lack of traditional structure in a milieu participatory democracy. To incorporate themselves into the system they must accept such democratic ideals as equality among staff and patients, group decision making, and free self-expression and give up some of their traditional ideas about staff and patient roles, treatment modalities, and the therapeutic environment. The author was a first-year resident in psychiatry on a university hospital inpatient therapeutic community; he discusses the conflicts between residents, who often adopt a "we-they" attitude, and the permanent staff, whose protectiveness of the ward community reflects their personal commitment to its ideals.

  11. Sleep behaviors and attitudes among internal medicine housestaff in a U.S. university-based residency program.

    Science.gov (United States)

    Rosen, Ilene M; Bellini, Lisa M; Shea, Judy A

    2004-05-01

    Physicians-in-training are susceptible to fatigue given their prolonged duty hours. Sleep deprivation has been shown to alter perceptions of sleepiness and performance. This study examined the state of sleepiness and attitudes about sleep and performance of work- and non-work-related tasks among incoming and current housestaff; and how rotation, call cycle, and call status are related to acute and chronic sleep deprivation and perceptions of sleepiness. A survey instrument was administered in June 2001 to 53 incoming interns and 79 current housestaff at the University Pennsylvania School of Medicine, a university-based internal medicine residency program. All 132 participants (100%) completed the instrument. Acute sleep deprivation was experienced by 34% of the current housestaff and 64% of current housestaff were chronically sleep deprived. Current housestaff admitted to the possibility of dozing while performing various work-related tasks such as writing notes in charts (69%), reviewing medication lists (61%), interpreting labs (51%), and writing orders (46%). At least half of all respondents felt their patients received good care despite residents' sleepiness and as many believed sleep deprivation was a necessary part of training. Nearly half (48%) of current housestaff rotating on a ward service reported acute sleep deprivation, as did 81% of those who were postcall. Over two-thirds of the housestaff on wards and in the ICU reported chronic sleep deprivation. Subjective sleepiness did not vary much across rotations, call cycle, and call status. Chronic and acute sleep deprivation contribute to residents' fatigue. Education could be targeted at attitudes. Further investigation of factors contributing to chronic sleep deprivation in this population is warranted.

  12. Vandalism: Environmental and Social Factors

    Science.gov (United States)

    Brown, Gregory; Devlin, Ann Sloan

    2003-01-01

    To explore the relationship between vandalism, college residence hall size, and a number of social factors, 688 college students completed the Core Alcohol and Drug Survey (Presley, Meilman, & Lyerla, 1994), the University Residence Environment Scale (Moos, 1988), and answered questions about their television habits and athletic participation.…

  13. Magnetoresistance in quantum Hall metals due to Pancharatnam ...

    Indian Academy of Sciences (India)

    Abstract. We derive the trial Hall resistance formula for the quantum Hall metals to address both the integer and fractional quantum Hall effects. Within the degenerate (and crossed) Landau levels, and in the presence of changing magnetic field strength, one can invoke two physical processes responsible for the electron ...

  14. Resident physicians' attitudes and confidence in communicating with patients: a pilot study at a Japanese university hospital.

    Science.gov (United States)

    Ishikawa, Hirono; Eto, Masato; Kitamura, Kiyoshi; Kiuchi, Takahiro

    2014-09-01

    This study aimed to explore the relationships among physicians' confidence in conducting medical interviews, their attitudes toward the patient-physician relationship, and undergraduate training in communication skills among resident physicians in Japan. Participants were 63 first-year resident physicians at a university hospital in Tokyo. The Physician Confidence in the Medical Interview scale (PCMI) was constructed based on the framework of the Calgary-Cambridge Guide. Additionally, participants' attitudes toward the patient-physician relationship (Patient-Practitioner Orientation Scale; PPOS), undergraduate experience of communication skills training, and demographic characteristics were assessed through a self-reported questionnaire. The internal consistency of the PCMI and PPOS scales were adequate. As expected from the undergraduate curriculum for medical interviews in Japan, residents had relatively higher confidence in their communication skills with respect to gathering information and building the relationship, whereas less confident about sharing information and planning treatment. The PCMI was associated with a more patient-centered attitude as measured by the PPOS. These scales could be useful tools to measure physicians' confidence and attitudes in communicating with patients and to explore their changes through medical education. Residency programs should consider including systematic training and assessment in communication skills related to sharing information and planning treatment. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  15. Spin hall effect associated with SU(2) gauge field

    Science.gov (United States)

    Tao, Y.

    2010-01-01

    In this paper, we focus on the connection between spin Hall effect and spin force. Here we investigate that the spin force due to spin-orbit coupling, which, in two-dimensional system, is equivalent to forces of Hirsch and Chudnovsky besides constant factors 3 and frac{3}{2} respectively, is a part of classic Anandan force, and that the spin Hall effect is an anomalous Hall effect. Furthermore, we develop the method of AC phase to derive the expression for the spin force, and note that the most basic spin Hall effect indeed originate from the AC phase and is therefore an intrinsic quantum mechanical property of spin. This method differs from approach of Berry phase in the study of anomalous Hall effect , which is the intrinsic property of the perfect crystal. On the other hand, we use an elegant skill to show that the Chudnovsky-Drude model is reasonable. Here we have improved the theoretical values of spin Hall conductivity of Chudnovsky. Compared to the theoretical values of spin Hall conductivity in the Chudnovsky-Drude model, ours are in better agreement with experimentation. Finally, we discuss the relation between spin Hall effect and fractional statistics.

  16. Hall Sensor Output Signal Fault-Detection & Safety Implementation Logic

    Directory of Open Access Journals (Sweden)

    Lee SangHun

    2016-01-01

    Full Text Available Recently BLDC motors have been popular in various industrial applications and electric mobility. Recently BLDC motors have been popular in various industrial applications and electric mobility. In most brushless direct current (BLDC motor drives, there are three hall sensors as a position reference. Low resolution hall effect sensor is popularly used to estimate the rotor position because of its good comprehensive performance such as low cost, high reliability and sufficient precision. Various possible faults may happen in a hall effect sensor. This paper presents a fault-tolerant operation method that allows the control of a BLDC motor with one faulty hall sensor and presents the hall sensor output fault-tolerant control strategy. The situations considered are when the output from a hall sensor stays continuously at low or high levels, or a short-time pulse appears on a hall sensor signal. For fault detection, identification of a faulty signal and generating a substitute signal, this method only needs the information from the hall sensors. There are a few research work on hall effect sensor failure of BLDC motor. The conventional fault diagnosis methods are signal analysis, model based analysis and knowledge based analysis. The proposed method is signal based analysis using a compensation signal for reconfiguration and therefore fault diagnosis can be fast. The proposed method is validated to execute the simulation using PSIM.

  17. The quantized Hall effect

    International Nuclear Information System (INIS)

    Klitzing von, K.

    1989-01-01

    The quantized Hall effect is theoretically explained in detail as are its basic properties. The explanation is completed with the pertinent mathematical relations and illustrative figures. Experimental data are critically assessed obtained by quantum transport measurement in a magnetic field on two-dimensional systems. The results are reported for a MOSFET silicon transistor and for GaAs-Al x Ga 1-x As heterostructures. The application is discussed of the quantized Hall effect in determining the fine structure constant or in implementing the resistance standard. (M.D.). 27 figs., 57 refs

  18. [Fifty years of residency in Psychiatry at the University of Montreal: relevance and necessity of the Residents' Association].

    Science.gov (United States)

    Thibault, Alexis

    2015-01-01

    In the context of the fiftieth anniversary celebrations of the Département de psychiatrie de l'Université de Montréal, the present article offers to retrace the history of the Psychiatry Resident's Association (ARPUM). Since the Association's activities and demands reflected the concerns of the time, a depiction of the Residency Program and exploration of the historical and administrative context, in each key period, is also undertaken. Multiple psychiatrists from every decade, who were once active members of the Association, were interviewed and asked to describe the Residency Program at their time, with its positive and negative aspects, based on their own personal experience as a resident, but also as a member of the organization. The interviewees were also invited to share their recollections of the various Association's demands, representations, activities and functioning, depending on the issues and periods. Various private and public archives were also used, in order to contextualize the residents' experiences and the Association's work. A brief exploration of the historical and political context that led to the creation of the organization is explained. Training and working conditions of residents at that time are reported, enabling the understanding of the first demands when the group was born. Historical jumps are then proposed, from decades to decades, in order to depict key issues, whether they were academic, clinical or organizational, through which the Association worked, over the evolution of the Residency Program. The internal functioning and its occasional problems throughout the years are also described, as is the role in organizing social and educational events. The Residency Program is in constant mutation, and the Association has played its part in shaping the psychiatric training at the Université de Montréal. Multiple positive and tangible impacts were and are still made possible from the collaborative work between the Département de

  19. Valley-chiral quantum Hall state in graphene superlattice structure

    Science.gov (United States)

    Tian, H. Y.; Tao, W. W.; Wang, J.; Cui, Y. H.; Xu, N.; Huang, B. B.; Luo, G. X.; Hao, Y. H.

    2016-05-01

    We theoretically investigate the quantum Hall effect in a graphene superlattice (GS) system, in which the two valleys of graphene are coupled together. In the presence of a perpendicular magnetic field, an ordinary quantum Hall effect is found with the sequence σxy=ν e^2/h(ν=0,+/-1,+/-2,\\cdots) . At the zeroth Hall platform, a valley-chiral Hall state stemming from the single K or K' valley is found and it is localized only on one sample boundary contributing to the longitudinal conductance but not to the Hall conductivity. Our findings may shed light on the graphene-based valleytronics applications.

  20. Air temperature gradient in large industrial hall

    Science.gov (United States)

    Karpuk, Michał; Pełech, Aleksander; Przydróżny, Edward; Walaszczyk, Juliusz; Szczęśniak, Sylwia

    2017-11-01

    In the rooms with dominant sensible heat load, volume airflow depends on many factors incl. pre-established temperature difference between exhaust and supply airflow. As the temperature difference is getting higher, airflow volume drops down, consequently, the cost of AHU is reduced. In high industrial halls with air exhaust grids located under the ceiling additional temperature gradient above working zone should be taken into consideration. In this regard, experimental research of the vertical air temperature gradient in high industrial halls were carried out for the case of mixing ventilation system The paper presents the results of air temperature distribution measurements in high technological hall (mechanically ventilated) under significant sensible heat load conditions. The supply airflow was delivered to the hall with the help of the swirl diffusers while exhaust grids were located under the hall ceiling. Basing on the air temperature distribution measurements performed on the seven pre-established levels, air temperature gradient in the area between 2.0 and 7.0 m above the floor was calculated and analysed.

  1. A new CMOS Hall angular position sensor

    Energy Technology Data Exchange (ETDEWEB)

    Popovic, R.S.; Drljaca, P. [Swiss Federal Inst. of Tech., Lausanne (Switzerland); Schott, C.; Racz, R. [SENTRON AG, Zug (Switzerland)

    2001-06-01

    The new angular position sensor consists of a combination of a permanent magnet attached to a shaft and of a two-axis magnetic sensor. The permanent magnet produces a magnetic field parallel with the magnetic sensor plane. As the shaft rotates, the magnetic field also rotates. The magnetic sensor is an integrated combination of a CMOS Hall integrated circuit and a thin ferromagnetic disk. The CMOS part of the system contains two or more conventional Hall devices positioned under the periphery of the disk. The ferromagnetic disk converts locally a magnetic field parallel with the chip surface into a field perpendicular to the chip surface. Therefore, a conventional Hall element can detect an external magnetic field parallel with the chip surface. As the direction of the external magnetic field rotates in the chip plane, the output voltage of the Hall element varies as the cosine of the rotation angle. By placing the Hall elements at the appropriate places under the disk periphery, we may obtain the cosine signals shifted by 90 , 120 , or by any other angle. (orig.)

  2. The quantum Hall effects: Philosophical approach

    Science.gov (United States)

    Lederer, P.

    2015-05-01

    The Quantum Hall Effects offer a rich variety of theoretical and experimental advances. They provide interesting insights on such topics as gauge invariance, strong interactions in Condensed Matter physics, emergence of new paradigms. This paper focuses on some related philosophical questions. Various brands of positivism or agnosticism are confronted with the physics of the Quantum Hall Effects. Hacking's views on Scientific Realism, Chalmers' on Non-Figurative Realism are discussed. It is argued that the difficulties with those versions of realism may be resolved within a dialectical materialist approach. The latter is argued to provide a rational approach to the phenomena, theory and ontology of the Quantum Hall Effects.

  3. Hall devices improve electric motor efficiency

    Science.gov (United States)

    Haeussermann, W.

    1979-01-01

    Efficiency of electric motors and generators is reduced by radial magnetic forces created by symmetric fields within device. Forces are sensed and counteracted by Hall devices on excitation or control windings. Hall generators directly measure and provide compensating control of anu asymmetry, eliminating additional measurements needed for calibration feedback control loop.

  4. Unconventional quantum Hall effect in Floquet topological insulators

    KAUST Repository

    Tahir, M.

    2016-07-27

    We study an unconventional quantum Hall effect for the surface states of ultrathin Floquet topological insulators in a perpendicular magnetic field. The resulting band structure is modified by photon dressing and the topological property is governed by the low-energy dynamics of a single surface. An exchange of symmetric and antisymmetric surface states occurs by reversing the lights polarization. We find a novel quantum Hall state in which the zeroth Landau level undergoes a phase transition from a trivial insulator state, with Hall conductivity αyx = 0 at zero Fermi energy, to a Hall insulator state with αyx = e2/2h. These findings open new possibilities for experimentally realizing nontrivial quantum states and unusual quantum Hall plateaus at (±1/2,±3/2,±5/2, ...)e2/h. © 2016 IOP Publishing Ltd Printed in the UK.

  5. Unconventional quantum Hall effect in Floquet topological insulators

    KAUST Repository

    Tahir, M.; Vasilopoulos, P.; Schwingenschlö gl, Udo

    2016-01-01

    We study an unconventional quantum Hall effect for the surface states of ultrathin Floquet topological insulators in a perpendicular magnetic field. The resulting band structure is modified by photon dressing and the topological property is governed by the low-energy dynamics of a single surface. An exchange of symmetric and antisymmetric surface states occurs by reversing the lights polarization. We find a novel quantum Hall state in which the zeroth Landau level undergoes a phase transition from a trivial insulator state, with Hall conductivity αyx = 0 at zero Fermi energy, to a Hall insulator state with αyx = e2/2h. These findings open new possibilities for experimentally realizing nontrivial quantum states and unusual quantum Hall plateaus at (±1/2,±3/2,±5/2, ...)e2/h. © 2016 IOP Publishing Ltd Printed in the UK.

  6. Accurate micro Hall effect measurements on scribe line pads

    DEFF Research Database (Denmark)

    Østerberg, Frederik Westergaard; Petersen, Dirch Hjorth; Wang, Fei

    2009-01-01

    Hall mobility and sheet carrier density are important parameters to monitor in advanced semiconductor production. If micro Hall effect measurements are done on small pads in scribe lines, these parameters may be measured without using valuable test wafers. We report how Hall mobility can...... be extracted from micro four-point measurements performed on a rectangular pad. The dimension of the investigated pad is 400 × 430 ¿m2, and the probe pitches range from 20 ¿m to 50 ¿m. The Monte Carlo method is used to find the optimal way to perform the Hall measurement and extract Hall mobility most...

  7. Formerly Utilized MED/AEC Sites Remedial Action Program. Project management plan for the decontamination of Jones Laboratory, Ryerson Physical Laboratory, and Eckhart Hall, the University of Chicago, Chicago, Illinois

    International Nuclear Information System (INIS)

    Flynn, K.F.; Smith, W.H.; Wynveen, R.A.

    1984-01-01

    The Department of Energy (DOE) has in place a plan for the decontamination and decommissioning of contaminated sites that had been formerly utilized by the Manhattan Engineering District (MED) and/or the Atomic Energy Commission. This plan is referred to as the Formerly Utilized Sites Remedial Action Program (FUSRAP). Among these sites are Jones Laboratory, Ryerson Physical Laboratory and Eckhart Hall of The University of Chicago at Chicago, Illinois. This document represents the Project Management Plan for the decontamination of these facilities. 13 references, 3 figures, 1 table

  8. Formerly Utilized MED/AEC Sites Remedial Action Program. Project management plan for the decontamination of Jones Laboratory, Ryerson Physical Laboratory, and Eckhart Hall, the University of Chicago, Chicago, Illinois

    Energy Technology Data Exchange (ETDEWEB)

    Flynn, K.F.; Smith, W.H.; Wynveen, R.A.

    1984-01-01

    The Department of Energy (DOE) has in place a plan for the decontamination and decommissioning of contaminated sites that had been formerly utilized by the Manhattan Engineering District (MED) and/or the Atomic Energy Commission. This plan is referred to as the Formerly Utilized Sites Remedial Action Program (FUSRAP). Among these sites are Jones Laboratory, Ryerson Physical Laboratory and Eckhart Hall of The University of Chicago at Chicago, Illinois. This document represents the Project Management Plan for the decontamination of these facilities. 13 references, 3 figures, 1 table.

  9. Extrinsic spin Hall effect in graphene

    Science.gov (United States)

    Rappoport, Tatiana

    The intrinsic spin-orbit coupling in graphene is extremely weak, making it a promising spin conductor for spintronic devices. In addition, many applications also require the generation of spin currents in graphene. Theoretical predictions and recent experimental results suggest one can engineer the spin Hall effect in graphene by greatly enhancing the spin-orbit coupling in the vicinity of an impurity. The extrinsic spin Hall effect then results from the spin-dependent skew scattering of electrons by impurities in the presence of spin-orbit interaction. This effect can be used to efficiently convert charge currents into spin-polarized currents. I will discuss recent experimental results on spin Hall effect in graphene decorated with adatoms and metallic cluster and show that a large spin Hall effect can appear due to skew scattering. While this spin-orbit coupling is small if compared with what it is found in metals, the effect is strongly enhanced in the presence of resonant scattering, giving rise to robust spin Hall angles. I will present our single impurity scattering calculations done with exact partial-wave expansions and complement the analysis with numerical results from a novel real-space implementation of the Kubo formalism for tight-binding Hamiltonians. The author acknowledges the Brazilian agencies CNPq, CAPES, FAPERJ and INCT de Nanoestruturas de Carbono for financial support.

  10. Hall current effects in dynamic magnetic reconnection solutions

    International Nuclear Information System (INIS)

    Craig, I.J.D.; Heerikhuisen, J.; Watson, P.G.

    2003-01-01

    The impact of Hall current contributions on flow driven planar magnetic merging solutions is discussed. The Hall current is important if the dimensionless Hall parameter (or normalized ion skin depth) satisfies c H >η, where η is the inverse Lundquist number for the plasma. A dynamic analysis of the problem shows, however, that the Hall current initially manifests itself, not by modifying the planar reconnection field, but by inducing a non-reconnecting perpendicular 'separator' component in the magnetic field. Only if the stronger condition c H 2 >η is satisfied can Hall currents be expected to affect the planar merging. These analytic predictions are then tested by performing a series of numerical experiments in periodic geometry, using the full system of planar magnetohydrodynamic (MHD) equations. The numerical results confirm that the nature of the merging changes dramatically when the Hall coupling satisfies c H 2 >η. In line with the analytic treatment of sheared reconnection, the coupling provided by the Hall term leads to the emergence of multiple current layers that can enhance the global Ohmic dissipation at the expense of the reconnection rate. However, the details of the dissipation depend critically on the symmetries of the simulation, and when the merging is 'head-on' (i.e., comprises fourfold symmetry) the reconnection rate can be enhanced

  11. Optimization of Cylindrical Hall Thrusters

    International Nuclear Information System (INIS)

    Raitses, Yevgeny; Smirnov, Artem; Granstedt, Erik; Fisch, Nathaniel J.

    2007-01-01

    The cylindrical Hall thruster features high ionization efficiency, quiet operation, and ion acceleration in a large volume-to-surface ratio channel with performance comparable with the state-of-the-art annular Hall thrusters. These characteristics were demonstrated in low and medium power ranges. Optimization of miniaturized cylindrical thrusters led to performance improvements in the 50-200W input power range, including plume narrowing, increased thruster efficiency, reliable discharge initiation, and stable operation.

  12. Optimization of Cylindrical Hall Thrusters

    International Nuclear Information System (INIS)

    Raitses, Yevgeny; Smirnov, Artem; Granstedt, Erik; Fi, Nathaniel J.

    2007-01-01

    The cylindrical Hall thruster features high ionization efficiency, quiet operation, and ion acceleration in a large volume-to-surface ratio channel with performance comparable with the state-of-the-art annular Hall thrusters. These characteristics were demonstrated in low and medium power ranges. Optimization of miniaturized cylindrical thrusters led to performance improvements in the 50-200W input power range, including plume narrowing, increased thruster efficiency, reliable discharge initiation, and stable operation

  13. Pediatric Resident Academic Projects While on Global Health Electives: Ten Years of Experience at the University of Minnesota.

    Science.gov (United States)

    Pitt, Michael B; Slusher, Tina M; Howard, Cynthia R; Cole, Valerie B; Gladding, Sophia P

    2017-07-01

    Many residency programs require residents to complete an academic project as part of a global health (GH) elective. However, there has been little description of the range of projects residents have pursued during GH electives or the extent to which these projects are consistent with proposed best practices. The authors conducted a document review of 67 written summaries or copies of presentations of academic projects (hereafter, summaries) completed by pediatric and medicine-pediatric residents at the University of Minnesota while on GH electives from 2005 to 2015. Two authors independently coded each summary for the type of project completed; when the project idea was generated; explicit mention of a mentor from the home institution, host institution, or both; whether a needs assessment was conducted; and whether there were plans for sustainability. Most of the 67 projects were categorized into one of three project types: quality/process improvement (28 [42%]), education (18 [27%]), or clinical research (14 [21%]). Most summaries explicitly mentioned a mentor (45 [67%]), reported conducting a needs assessment (38 [57%]), and indicated sustainability plans (45 [67%]). Of the 42 summaries that indicated the timing of idea generation, 30 (71%) indicated the idea was developed after arriving at the host site. Residents undertook a wide range of academic projects during GH electives, most commonly quality/process improvement and education projects. The projects were largely aligned with best practices, with most summaries indicating the resident worked with a mentor, conducted a needs assessment, and made plans for sustainability.

  14. Spin-singlet hierarchy in the fractional quantum Hall effect

    OpenAIRE

    Ino, Kazusumi

    1999-01-01

    We show that the so-called permanent quantum Hall states are formed by the integer quantum Hall effects on the Haldane-Rezayi quantum Hall state. Novel conformal field theory description along with this picture is deduced. The odd denominator plateaux observed around $\

  15. Anisotropic intrinsic spin Hall effect in quantum wires

    International Nuclear Information System (INIS)

    Cummings, A W; Akis, R; Ferry, D K

    2011-01-01

    We use numerical simulations to investigate the spin Hall effect in quantum wires in the presence of both Rashba and Dresselhaus spin-orbit coupling. We find that the intrinsic spin Hall effect is highly anisotropic with respect to the orientation of the wire, and that the nature of this anisotropy depends strongly on the electron density and the relative strengths of the Rashba and Dresselhaus spin-orbit couplings. In particular, at low densities, when only one subband of the quantum wire is occupied, the spin Hall effect is strongest for electron momentum along the [1-bar 10] axis, which is the opposite of what is expected for the purely 2D case. In addition, when more than one subband is occupied, the strength and anisotropy of the spin Hall effect can vary greatly over relatively small changes in electron density, which makes it difficult to predict which wire orientation will maximize the strength of the spin Hall effect. These results help to illuminate the role of quantum confinement in spin-orbit-coupled systems, and can serve as a guide for future experimental work on the use of quantum wires for spin-Hall-based spintronic applications. (paper)

  16. Zheng Manqing: The Memorial Hall and Legacy of the Master of Five Excellences in Taiwan

    Directory of Open Access Journals (Sweden)

    Russ Mason

    2012-07-01

    Full Text Available Professor Zheng Manqing (1902-1975, a fine artist and a notable taijiquan disciple of Yang Chengfu, emigrated to Taiwan in 1949 following the Chinese civil war between the Guomindang and Maoist factions. Under Republic of China President Chiang Kai-shek’s Cultural Renaissance Movement, Zheng played an important role in preserving the cultural treasures of traditional China. During the period of Mao Zedong’s Cultural Revolution when the Mainland was veiled to foreign eyes behind the Bamboo Curtain, Zheng was instrumental in introducing taijiquan and other elements of Chinese culture to the West. Zheng passed away at his home in Yonghe, Taiwan in 1975 but not before establishing an international reputation for his mastery in taijiquan and other arts. Recently, a portion of his former residence was converted into a memorial hall (the Zheng Manqing Jinian Guan by senior students interested in preserving his martial tradition, paintings, calligraphy, and other artifacts. This article provides a brief history of Zheng’s life and his legacy in Taiwan, as well as a photographic tour of the Zheng Manqing Memorial Hall.

  17. Surface and 3D Quantum Hall Effects from Engineering of Exceptional Points in Nodal-Line Semimetals

    Science.gov (United States)

    Molina, Rafael A.; González, José

    2018-04-01

    We show that, under a strong magnetic field, a 3D nodal-line semimetal is driven into a topological insulating phase in which the electronic transport takes place at the surface of the material. When the magnetic field is perpendicular to the nodal ring, the surface states of the semimetal are transmuted into Landau states which correspond to exceptional points, i.e., branch points in the spectrum of a non-Hermitian Hamiltonian which arise upon the extension to complex values of the momentum. The complex structure of the spectrum then allows us to express the number of zero-energy flat bands in terms of a new topological invariant counting the number of exceptional points. When the magnetic field is parallel to the nodal ring, we find that the bulk states are built from the pairing of surfacelike evanescent waves, giving rise to a 3D quantum Hall effect with a flat level of Landau states residing in parallel 2D slices of the 3D material. The Hall conductance is quantized in either case in units of e2/h , leading in the 3D Hall effect to a number of channels growing linearly with the section of the surface and opening the possibility to observe a macroscopic chiral current at the surface of the material.

  18. The relationship between cultural intelligence and social compatibility in Isfahan University of Medical Sciences dormitories resident students.

    Science.gov (United States)

    Keyvanara, Mahmoud; Yarmohammadian, Mohammad Hossein; Soltani, Batoul

    2014-01-01

    Cultural intelligence and social compatibility are two acquired processes that their education and reinforcement between dormitory's students who have inter cultural interactions with each other can conclude with results that tension diminution, inter cultural contrast and conflict, social divisions and consequently healthy and peaceful relationships and governance and finally mental peace, and health are of its most important. Hence, the research has been occurring in order to the determination of cultural intelligence relationship with the social compatibility of Isfahan University of Medical Sciences dormitories resident students in 2012. The research method is descriptive-correlation, and its population is composed of all Isfahan University of Medical Sciences dormitories resident students in 2012 that were totally 2500 persons. The two steps sampling method have been used, group sampling and random sampling has been occurring at first and second steps and totally 447 persons were selected. Research data were collected via Earley and Ang cultural intelligence questionnaire with 0.76 Cronbach's alpha Coefficient and California social compatibility standard questionnaire with higher than 0.70 Cronbach's alpha factor. Questionnaire data have been analyzed with the SPSS software and results have been presented in the shape of descriptions and statistics. Results showed that there is a direct significant relationship (P intelligence and the social adjustment in students living in Isfahan University of Medical Sciences dormitories and also there is a direct significant relationship in the level of (P intelligence; however, there is no significant relationship between cognitive and behavioral dimensions of cultural intelligence and social adjustment (P > 0.05). Cultural intelligence and cognitive and motivational addition in dimensions of students living in Isfahan University of Medical Sciences dormitories increase their social integration, therefore, cultural

  19. The Hall module of an exact category with duality

    OpenAIRE

    Young, Matthew B.

    2012-01-01

    We construct from a finitary exact category with duality a module over its Hall algebra, called the Hall module, encoding the first order self-dual extension structure of the category. We study in detail Hall modules arising from the representation theory of a quiver with involution. In this case we show that the Hall module is naturally a module over the specialized reduced sigma-analogue of the quantum Kac-Moody algebra attached to the quiver. For finite type quivers, we explicitly determin...

  20. Theory of spin Hall effect

    OpenAIRE

    Chudnovsky, Eugene M.

    2007-01-01

    An extension of Drude model is proposed that accounts for spin and spin-orbit interaction of charge carriers. Spin currents appear due to combined action of the external electric field, crystal field and scattering of charge carriers. The expression for spin Hall conductivity is derived for metals and semiconductors that is independent of the scattering mechanism. In cubic metals, spin Hall conductivity $\\sigma_s$ and charge conductivity $\\sigma_c$ are related through $\\sigma_s = [2 \\pi \\hbar...

  1. Anode sheath in Hall thrusters

    International Nuclear Information System (INIS)

    Dorf, L.; Semenov, V.; Raitses, Y.

    2003-01-01

    A set of hydrodynamic equations is used to describe quasineutral plasma in ionization and acceleration regions of a Hall thruster. The electron distribution function and Poisson equation are invoked for description of a near-anode region. Numerical solutions suggest that steady-state operation of a Hall thruster can be achieved at different anode sheath regimes. It is shown that the anode sheath depends on the thruster operating conditions, namely the discharge voltage and the mass flow rate

  2. Real-space imaging of fractional quantum Hall liquids

    Science.gov (United States)

    Hayakawa, Junichiro; Muraki, Koji; Yusa, Go

    2013-01-01

    Electrons in semiconductors usually behave like a gas--as independent particles. However, when confined to two dimensions under a perpendicular magnetic field at low temperatures, they condense into an incompressible quantum liquid. This phenomenon, known as the fractional quantum Hall (FQH) effect, is a quantum-mechanical manifestation of the macroscopic behaviour of correlated electrons that arises when the Landau-level filling factor is a rational fraction. However, the diverse microscopic interactions responsible for its emergence have been hidden by its universality and macroscopic nature. Here, we report real-space imaging of FQH liquids, achieved with polarization-sensitive scanning optical microscopy using trions (charged excitons) as a local probe for electron spin polarization. When the FQH ground state is spin-polarized, the triplet/singlet intensity map exhibits a spatial pattern that mirrors the intrinsic disorder potential, which is interpreted as a mapping of compressible and incompressible electron liquids. In contrast, when FQH ground states with different spin polarization coexist, domain structures with spontaneous quasi-long-range order emerge, which can be reproduced remarkably well from the disorder patterns using a two-dimensional random-field Ising model. Our results constitute the first reported real-space observation of quantum liquids in a class of broken symmetry state known as the quantum Hall ferromagnet.

  3. Magnetically Filtered Faraday Probe for Measuring the Ion Current Density Profile of a Hall Thruster

    National Research Council Canada - National Science Library

    Rovey, Joshua L; Walker, Mitchell L. R; Gallimore, Alec D; Peterson, Peter Y

    2006-01-01

    .../s. The probes are evaluated on a xenon propellant Hall thruster in the University of Michigan Large Vacuum Test Facility at operating pressures within the range of 4.4 x 10(-4) Pa Xe (3.3 x 10(-6) Torr Xe) to 1.1 10(-3) Pa Xe (8.4 x 10(-6) Torr Xe...

  4. Quantized Hall conductance as a topological invariant

    International Nuclear Information System (INIS)

    Niu, Q.; Thouless, Ds.J.; Wu, Y.S.

    1984-10-01

    Whenever the Fermi level lies in a gap (or mobility gap) the bulk Hall conductance can be expressed in a topologically invariant form showing the quantization explicitly. The new formulation generalizes the earlier result by TKNN to the situation where many body interaction and substrate disorder are also present. When applying to the fractional quantized Hall effect we draw the conclusion that there must be a symmetry breaking in the many body ground state. The possibility of writing the fractionally quantized Hall conductance as a topological invariant is also carefully discussed. 19 references

  5. The Alcohol Use Disorders Identification Scale (AUDIT) normative scores for a multiracial sample of Rhodes University residence students.

    Science.gov (United States)

    Young, Charles; Mayson, Tamara

    2010-06-01

    The objective of this research is to obtain accurate drinking norms for students living in the university residences in preparation for future social norms interventions that would allow individual students to compare their drinking to an appropriate reference group. Random cluster sampling was used to obtain data from 318 residence students who completed the Alcohol Use Disorders Identification Test (AUDIT), a brief, reliable and valid screening measure designed by the World Health Organisation (Babor et al. 2001). The Cronbach alpha coefficient of 0.83 reported for this multicultural sample is high, suggesting that the AUDIT may be reliably used in this and similar contexts. Normative scores are reported in the form of percentiles. Comparisons between the portions of students drinking safely and hazardously according to race and gender indicate that while male students are drinking no more hazardously than female students, white students drink far more hazardously than black students. These differences suggest that both race- and gender-specific norms would be essential for an effective social norms intervention in this multicultural South African context. Finally, the racialised drinking patterns might reflect an informal segregation of social space at Rhodes University.

  6. Blended Learning in Obstetrics and Gynecology Resident Education: Impact on Resident Clinical Performance.

    Science.gov (United States)

    Ghareeb, Allen; Han, Heeyoung; Delfino, Kristin; Taylor, Funminiyi

    2016-01-01

    Effects of residents' blended learning on their clinical performance have rarely been reported. A blended learning pilot program was instituted at Southern Illinois University School of Medicine's Obstetrics and Gynecology program. One of the modules was chronic hypertension in pregnancy. We sought to evaluate if the resident blended learning was transferred to their clinical performance six months after the module. A review of patient charts demonstrated inadequate documentation of history, evaluation, and counseling of patients with chronic hypertension at the first prenatal visit by Obstetrics and Gynecology (OB/GYN) residents. A blended learning module on chronic hypertension in pregnancy was then provided to the residents. A retrospective chart review was then performed to assess behavioral changes in the OB/GYN residents. This intervention was carried out at the Department of Obstetrics and Gynecology, Southern Illinois University. All 16 OB/GYN residents were enrolled in this module as part of their educational curriculum. A query of all prenatal patients diagnosed with chronic hypertension presenting to the OB/GYN resident clinics four months prior to the implementation of the blended learning module (March 2015-June 2015) and six months after (July 20, 2015-February 2016) was performed. Data were collected from outpatient charts utilizing the electronic medical record. Data were abstracted from resident documentation at the first prenatal visit. The residents thought that the blended learning module was applicable to performance improvement in the real-world setting. Patients evaluated before ( n = 10) and after ( n = 7) the intervention were compared. After the intervention, there was an increase in assessment of baseline liver enzymes, referral for electrocardiogram, and early assessment for diabetes in the obese patients. More patients were provided a blood pressure cuff after the module (71.4% vs. 20%). Data were provided to the residents in an

  7. Testing the Topological Nature of the Fractional Quantum Hall Edge

    International Nuclear Information System (INIS)

    Jolad, Shivakumar; Jain, Jainendra K.

    2009-01-01

    We carry out numerical diagonalization for much larger systems than before by restricting the fractional quantum Hall (FQH) edge excitations to a basis that is exact for a short-range interaction and very accurate for the Coulomb interaction. This enables us to perform substantial tests of the predicted universality of the edge physics. Our results suggest the possibility that the behavior of the FQH edge is intrinsically nonuniversal, even in the absence of edge reconstruction, and therefore may not bear a sharp and unique relation to the nature of the bulk FQH state

  8. Halls Lake 1990

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Salt marsh habitats along the shoreline of Halls Lake are threatened by wave erosion, but the reconstruction of barrier islands to reduce this erosion will modify or...

  9. Nobel Prize in physics 1985: Quantum Hall effect

    International Nuclear Information System (INIS)

    Herrmann, R.

    1986-01-01

    The conditions (like very strong magnetic fields, ultralow temperatures, and occurrence of a two-dimensional electron gas in microelectronic structures) for the measurement of the quantum Hall effect are explained. Two possible measuring methods are described. Measuring results for p-Si-MOSFET, GaAs/AlGaAs heterojuntions and grain boundaries in InSb crystals are reported. Differences between normal (integer) and fractional quantum Hall effect are discussed. One of the important consequences is that by means of the quantum Hall effect the value h/e 2 can be determined with very high accuracy. In 1985 Klaus von Klitzing was awarded the Nobel Prize for his work on the quantum Hall effect

  10. Intrinsic superspin Hall current

    Science.gov (United States)

    Linder, Jacob; Amundsen, Morten; Risinggârd, Vetle

    2017-09-01

    We discover an intrinsic superspin Hall current: an injected charge supercurrent in a Josephson junction containing heavy normal metals and a ferromagnet generates a transverse spin supercurrent. There is no accompanying dissipation of energy, in contrast to the conventional spin Hall effect. The physical origin of the effect is an antisymmetric spin density induced among transverse modes ky near the interface of the superconductor arising due to the coexistence of p -wave and conventional s -wave superconducting correlations with a belonging phase mismatch. Our predictions can be tested in hybrid structures including thin heavy metal layers combined with strong ferromagnets and ordinary s -wave superconductors.

  11. Developing an integrated evidence-based medicine curriculum for family medicine residency at the University of Alberta.

    Science.gov (United States)

    Allan, G Michael; Korownyk, Christina; Tan, Amy; Hindle, Hugh; Kung, Lina; Manca, Donna

    2008-06-01

    There is general consensus in the academic community that evidence-based medicine (EBM) teaching is essential. Unfortunately, many postgraduate programs have significant weakness in their EBM programs. The Family Medicine Residency committee at the University of Alberta felt their EBM curriculum would benefit from critical review and revision. An EBM Curriculum Committee was created to evaluate previous components and develop new strategies as needed. Input from stakeholders including faculty and residents was sought, and evidence regarding the teaching and practical application of EBM was gathered. The committee drafted goals and objectives, the primary of which were to assist residents to (1) become competent self-directed, lifelong learners with skills to effectively and efficiently keep up to date, and 2) develop EBM skills to solve problems encountered in daily practice. New curriculum components, each evidence based, were introduced in 2005 and include a family medicine EBM workshop to establish basic EBM knowledge; a Web-based Family Medicine Desktop promoting easier access to evidence-based Internet resources; a brief evidence-based assessment of the research project enhancing integration of EBM into daily practice; and a journal club to support peer learning and growth of rapid appraisal skills. Issues including time use, costs, and change management are discussed. Ongoing evaluation of the curriculum and its components is a principal factor of the design, allowing critical review and adaptation of the curriculum. The first two years of the curriculum have yielded positive feedback from faculty and statistically significant improvement in multiple areas of residents' opinions of the curriculum and comfort with evidence-based practice.

  12. The quantum Hall's effect: A quantum electrodynamic phenomenon

    International Nuclear Information System (INIS)

    Arbab, A. I.

    2012-01-01

    We have applied Maxwell's equations to study the physics of quantum Hall's effect. The electromagnetic properties of this system are obtained. The Hall's voltage, V H = 2πħ 2 n s /em, where n s is the electron number density, for a 2-dimensional system, and h = 2πħ is the Planck's constant, is found to coincide with the voltage drop across the quantum capacitor. Consideration of the cyclotronic motion of electrons is found to give rise to Hall's resistance. Ohmic resistances in the horizontal and vertical directions have been found to exist before equilibrium state is reached. At a fundamental level, the Hall's effect is found to be equivalent to a resonant LCR circuit with L H = 2π m/e 2 n s and C H = me 2 /2πħ 2 n s satisfying the resonance condition with resonant frequency equal to the inverse of the scattering (relaxation) time, τ s . The Hall's resistance is found to be R H = √L H /C H . The Hall's resistance may be connected with the impedance that the electron wave experiences when it propagates in the 2-dimensional gas. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  13. Determinants of Malaria Prevention and Treatment Seeking Behaviours of Pregnant Undergraduates Resident in University Hostels, South-East Nigeria

    Directory of Open Access Journals (Sweden)

    Anthonia Ukamaka Chinweuba

    2017-01-01

    Full Text Available This cross-sectional descriptive survey investigated determinants of malaria prevention and treatment seeking behaviours of pregnant undergraduates resident in university hostels, South-East Nigeria. Purposive sampling was used to enrol 121 accessible and consenting undergraduates with self-revealed and noticeable pregnancy residing in twenty-three female hostels of four university campuses in Enugu State, Nigeria. Structured interview guide developed based on reviewed literature and WHO-recommended malaria prevention and treatment measures was used to collect students’ self-report data on malaria preventive health behaviours, sick role behaviours, and clinic use using mixed methods. The WHO-recommended malaria prevention measures were sparingly used. Some believed that pregnancy does not play any role in a woman’s reaction to malaria infection. Only 41 (50.6% visited a hospital for screening and treatment. Thirty-four (28.1% used antimalaria medicine bought from chemist shop or over-the-counter medicines, while 33 (27.3% used untreated net. The students were more likely to complete their antimalaria medicine when they were sick with malaria infection than for prevention (p=0.0186. Knowledge, academic schedule, cultural influence on perception and decision-making, and accessibility of health facility were key determinants of the women’s preventive and treatment seeking behaviours. Health education on malaria prevention and dangers of drug abuse should form part of orientation lectures for all freshmen. University health centres should be upgraded to provide basic antenatal care services.

  14. Fractionalizing Majorana Fermions: Non-Abelian Statistics on the Edges of Abelian Quantum Hall States

    Directory of Open Access Journals (Sweden)

    Netanel H. Lindner

    2012-10-01

    Full Text Available We study the non-Abelian statistics characterizing systems where counterpropagating gapless modes on the edges of fractional quantum Hall states are gapped by proximity coupling to superconductors and ferromagnets. The most transparent example is that of a fractional quantum spin Hall state, in which electrons of one spin direction occupy a fractional quantum Hall state of ν=1/m, while electrons of the opposite spin occupy a similar state with ν=-1/m. However, we also propose other examples of such systems, which are easier to realize experimentally. We find that each interface between a region on the edge coupled to a superconductor and a region coupled to a ferromagnet corresponds to a non-Abelian anyon of quantum dimension sqrt[2m]. We calculate the unitary transformations that are associated with the braiding of these anyons, and we show that they are able to realize a richer set of non-Abelian representations of the braid group than the set realized by non-Abelian anyons based on Majorana fermions. We carry out this calculation both explicitly and by applying general considerations. Finally, we show that topological manipulations with these anyons cannot realize universal quantum computation.

  15. Spontaneous Hall effect in a chiral p-wave superconductor

    Science.gov (United States)

    Furusaki, Akira; Matsumoto, Masashige; Sigrist, Manfred

    2001-08-01

    In a chiral superconductor with broken time-reversal symmetry a ``spontaneous Hall effect'' may be observed. We analyze this phenomenon by taking into account the surface properties of a chiral superconductor. We identify two main contributions to the spontaneous Hall effect. One contribution originates from the Bernoulli (or Lorentz) force due to spontaneous currents running along the surfaces of the superconductor. The other contribution has a topological origin and is related to the intrinsic angular momentum of Cooper pairs. The latter can be described in terms of a Chern-Simons-like term in the low-energy field theory of the superconductor and has some similarities with the quantum Hall effect. The spontaneous Hall effect in a chiral superconductor is, however, nonuniversal. Our analysis is based on three approaches to the problem: a self-consistent solution of the Bogoliubov-de Gennes equation, a generalized Ginzburg-Landau theory, and a hydrodynamic formulation. All three methods consistently lead to the same conclusion that the spontaneous Hall resistance of a two-dimensional superconducting Hall bar is of order h/(ekFλ)2, where kF is the Fermi wave vector and λ is the London penetration depth; the Hall resistance is substantially suppressed from a quantum unit of resistance. Experimental issues in measuring this effect are briefly discussed.

  16. Anomalous Hall effect in Fe/Gd bilayers

    KAUST Repository

    Xu, W. J.; Zhang, Bei; Liu, Z. X.; Wang, Z.; Li, W.; Wu, Z. B.; Yu, R. H.; Zhang, Xixiang

    2010-01-01

    Non-monotonic dependence of anomalous Hall resistivity on temperature and magnetization, including a sign change, was observed in Fe/Gd bilayers. To understand the intriguing observations, we fabricated the Fe/Gd bilayers and single layers of Fe and Gd simultaneously. The temperature and field dependences of longitudinal resistivity, Hall resistivity and magnetization in these films have also been carefully measured. The analysis of these data reveals that these intriguing features are due to the opposite signs of Hall resistivity/or spin polarization and different Curie temperatures of Fe and Gd single-layer films. Copyright (C) EPLA, 2010

  17. Anomalous Hall effect in Fe/Gd bilayers

    KAUST Repository

    Xu, W. J.

    2010-04-01

    Non-monotonic dependence of anomalous Hall resistivity on temperature and magnetization, including a sign change, was observed in Fe/Gd bilayers. To understand the intriguing observations, we fabricated the Fe/Gd bilayers and single layers of Fe and Gd simultaneously. The temperature and field dependences of longitudinal resistivity, Hall resistivity and magnetization in these films have also been carefully measured. The analysis of these data reveals that these intriguing features are due to the opposite signs of Hall resistivity/or spin polarization and different Curie temperatures of Fe and Gd single-layer films. Copyright (C) EPLA, 2010

  18. Anomalous Hall effect

    Czech Academy of Sciences Publication Activity Database

    Nagaosa, N.; Sinova, Jairo; Onoda, S.; MacDonald, A. H.; Ong, N. P.

    2010-01-01

    Roč. 82, č. 2 (2010), s. 1539-1592 ISSN 0034-6861 Institutional research plan: CEZ:AV0Z10100521 Keywords : anomalous Hall effect * spintronics Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 51.695, year: 2010

  19. Hall effect in a strong magnetic field: Direct comparisons of compressible magnetohydrodynamics and the reduced Hall magnetohydrodynamic equations

    International Nuclear Information System (INIS)

    Martin, L. N.; Dmitruk, P.; Gomez, D. O.

    2010-01-01

    In this work we numerically test a model of Hall magnetohydrodynamics in the presence of a strong mean magnetic field: the reduced Hall magnetohydrodynamic model (RHMHD) derived by [Gomez et al., Phys. Plasmas 15, 102303 (2008)] with the addition of weak compressible effects. The main advantage of this model lies in the reduction of computational cost. Nevertheless, up until now the degree of agreement with the original Hall MHD system and the range of validity in a regime of turbulence were not established. In this work direct numerical simulations of three-dimensional Hall MHD turbulence in the presence of a strong mean magnetic field are compared with simulations of the weak compressible RHMHD model. The results show that the degree of agreement is very high (when the different assumptions of RHMHD, such as spectral anisotropy, are satisfied). Nevertheless, when the initial conditions are isotropic but the mean magnetic field is maintained strong, the results differ at the beginning but asymptotically reach a good agreement at relatively short times. We also found evidence that the compressibility still plays a role in the dynamics of these systems, and the weak compressible RHMHD model is able to capture these effects. In conclusion the weak compressible RHMHD model is a valid approximation of the Hall MHD turbulence in the relevant physical context.

  20. Terahertz spectroscopy on Faraday and Kerr rotations in a quantum anomalous Hall state.

    Science.gov (United States)

    Okada, Ken N; Takahashi, Youtarou; Mogi, Masataka; Yoshimi, Ryutaro; Tsukazaki, Atsushi; Takahashi, Kei S; Ogawa, Naoki; Kawasaki, Masashi; Tokura, Yoshinori

    2016-07-20

    Electrodynamic responses from three-dimensional topological insulators are characterized by the universal magnetoelectric term constituent of the Lagrangian formalism. The quantized magnetoelectric coupling, which is generally referred to as topological magnetoelectric effect, has been predicted to induce exotic phenomena including the universal low-energy magneto-optical effects. Here we report the experimental indication of the topological magnetoelectric effect, which is exemplified by magneto-optical Faraday and Kerr rotations in the quantum anomalous Hall states of magnetic topological insulator surfaces by terahertz magneto-optics. The universal relation composed of the observed Faraday and Kerr rotation angles but not of any material parameters (for example, dielectric constant and magnetic susceptibility) well exhibits the trajectory towards the fine structure constant in the quantized limit.

  1. Destruction of the fractional quantum Hall effect by disorder

    International Nuclear Information System (INIS)

    Laughlin, R.B.

    1985-07-01

    It is suggested that Hall steps in the fractional quantum Hall effect are physically similar to those in the ordinary quantum Hall effect. This proposition leads to a simple scaling diagram containing a new type of fixed point, which is identified with the destruction of the fractional states by disorder. 15 refs., 3 figs

  2. A Hall probe technique for characterizing high-temperature superconductors

    International Nuclear Information System (INIS)

    Zhang, J.; Sheldon, P.; Ahrenkiel, R.K.

    1992-01-01

    Thin-film GaAs Hall probes were fabricated by molecular beam epitaxy technology. A contactless technique was developed to characterize thin-film, high-temperature superconducting (HTSC) materials. The Hall probes detected the ac magnetic flux penetration through the high-temperature superconducting materials. The Hall detector has advantages over the mutual inductance magnetic flux detector

  3. W∞ gauge theory and the quantum Hall effect

    International Nuclear Information System (INIS)

    Shizuya, K.

    1994-05-01

    It is shown that a planar system of Hall electrons coupled to an applied electromagnetic field is written in the form of a W ∞ gauge theory. The associated W ∞ gauge field is expressed nonlinearly in terms of an infinite set of multipoles of the electromagnetic field. The W ∞ transformations generate mixing among the Landau levels. They provide a systematic way to classify the electromagnetic characteristics of the Hall system according to the resolution of external probes. In particular, an exact long-wavelength connection is derived between the carrier density and the Hall conductance in the presence of electron-electron interactions. Our approach is complementary to an earlier one and reveals a dual role the W ∞ gauge symmetry plays in the Hall dynamics. (author)

  4. Intrinsic quantum spin Hall and anomalous Hall effects in h-Sb/Bi epitaxial growth on a ferromagnetic MnO2 thin film.

    Science.gov (United States)

    Zhou, Jian; Sun, Qiang; Wang, Qian; Kawazoe, Yoshiyuki; Jena, Puru

    2016-06-07

    Exploring a two-dimensional intrinsic quantum spin Hall state with a large band gap as well as an anomalous Hall state in realizable materials is one of the most fundamental and important goals for future applications in spintronics, valleytronics, and quantum computing. Here, by combining first-principles calculations with a tight-binding model, we predict that Sb or Bi can epitaxially grow on a stable and ferromagnetic MnO2 thin film substrate, forming a flat honeycomb sheet. The flatness of Sb or Bi provides an opportunity for the existence of Dirac points in the Brillouin zone, with its position effectively tuned by surface hydrogenation. The Dirac points in spin up and spin down channels split due to the proximity effects induced by MnO2. In the presence of both intrinsic and Rashba spin-orbit coupling, we find two band gaps exhibiting a large band gap quantum spin Hall state and a nearly quantized anomalous Hall state which can be tuned by adjusting the Fermi level. Our findings provide an efficient way to realize both quantized intrinsic spin Hall conductivity and anomalous Hall conductivity in a single material.

  5. Plasmon Geometric Phase and Plasmon Hall Shift

    Science.gov (United States)

    Shi, Li-kun; Song, Justin C. W.

    2018-04-01

    The collective plasmonic modes of a metal comprise a simple pattern of oscillating charge density that yields enhanced light-matter interaction. Here we unveil that beneath this familiar facade plasmons possess a hidden internal structure that fundamentally alters its dynamics. In particular, we find that metals with nonzero Hall conductivity host plasmons with an intricate current density configuration that sharply departs from that of ordinary zero Hall conductivity metals. This nontrivial internal structure dramatically enriches the dynamics of plasmon propagation, enabling plasmon wave packets to acquire geometric phases as they scatter. At boundaries, these phases accumulate allowing plasmon waves that reflect off to experience a nonreciprocal parallel shift. This plasmon Hall shift, tunable by Hall conductivity as well as plasmon wavelength, displaces the incident and reflected plasmon trajectories and can be readily probed by near-field photonics techniques. Anomalous plasmon geometric phases dramatically enrich the nanophotonics toolbox, and yield radical new means for directing plasmonic beams.

  6. Signal conditioning and processing for metallic Hall sensors.

    Czech Academy of Sciences Publication Activity Database

    Entler, Slavomír; Ďuran, Ivan; Sládek, P.; Vayakis, G.; Kočan, M.

    2017-01-01

    Roč. 123, November (2017), s. 783-786 ISSN 0920-3796. [SOFT 2016: Symposium on Fusion Technology /29./. Prague, 05.09.2016-09.09.2016] R&D Projects: GA MŠk LG14002 Institutional support: RVO:61389021 Keywords : Hall sensor * Lock-in * Synchronous detection * Current spinning * Hall effect * Planar hall effect suppression Subject RIV: JF - Nuclear Energetics OBOR OECD: Nuclear related engineering Impact factor: 1.319, year: 2016 http://www.sciencedirect.com/science/article/pii/S0920379617305070

  7. Energy spectrum, dissipation, and spatial structures in reduced Hall magnetohydrodynamic

    Energy Technology Data Exchange (ETDEWEB)

    Martin, L. N.; Dmitruk, P. [Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires and IFIBA, CONICET, Ciudad Universitaria, 1428 Buenos Aires (Argentina); Gomez, D. O. [Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires and IFIBA, CONICET, Ciudad Universitaria, 1428 Buenos Aires (Argentina); Instituto de Astronomia y Fisica del Espacio, CONICET, Buenos Aires (Argentina)

    2012-05-15

    We analyze the effect of the Hall term in the magnetohydrodynamic turbulence under a strong externally supported magnetic field, seeing how this changes the energy cascade, the characteristic scales of the flow, and the dynamics of global magnitudes, with particular interest in the dissipation. Numerical simulations of freely evolving three-dimensional reduced magnetohydrodynamics are performed, for different values of the Hall parameter (the ratio of the ion skin depth to the macroscopic scale of the turbulence) controlling the impact of the Hall term. The Hall effect modifies the transfer of energy across scales, slowing down the transfer of energy from the large scales up to the Hall scale (ion skin depth) and carrying faster the energy from the Hall scale to smaller scales. The final outcome is an effective shift of the dissipation scale to larger scales but also a development of smaller scales. Current sheets (fundamental structures for energy dissipation) are affected in two ways by increasing the Hall effect, with a widening but at the same time generating an internal structure within them. In the case where the Hall term is sufficiently intense, the current sheet is fully delocalized. The effect appears to reduce impulsive effects in the flow, making it less intermittent.

  8. Spin disorder effect in anomalous Hall effect in MnGa

    Science.gov (United States)

    Mendonça, A. P. A.; Varalda, J.; Schreiner, W. H.; Mosca, D. H.

    2017-12-01

    We report on resistivity and Hall effect in MnGa thin films grown by molecular beam epitaxy on GaAs substrates. Highly (1 1 1)-textured MnGa film with L10 structure exhibits hard magnetic properties with coercivities as high as 20 kOe and spin disorder mechanisms contributing to the Hall conductivity at room temperature. Density functional theory calculations were performed to determine the intrinsic Berry curvature in the momentum space with chiral spin structure that results in an anomalous Hall conductivity of 127 (Ωcm)-1 comparable to that measured at low temperature. In addition to residual and side-jump contributions, which are enhanced by thermal activation, both anomalous Hall conductivity and Hall angle increase between 100 K and room temperature. The present results reinforce the potential of Mn-Ga system for developing Hall effect-based spintronic devices.

  9. Design and Testing of a Hall Effect Thruster with Additively Manufactured Components

    Science.gov (United States)

    Hopping, Ethan

    The UAH-78AM is a low-power Hall effect thruster developed at the University of Alabama in Huntsville to study the application of low-cost additive manufacturing in the design and fabrication of Hall thrusters. The goal of this project is to assess the feasibility of using unconventional materials to produce a low-cost functioning Hall effect thruster and consider how additive manufacturing can expand the design space and provide other benefits. The thruster features channel walls and a propellant distributor that were manufactured using 3D printing with a variety of materials including ABS, ULTEM, and glazed ceramic. A version of the thruster was tested at NASA Glenn Research Center to obtain performance metrics and to validate the ability of the thruster to produce thrust and sustain a discharge. The design of the thruster and the transient performance measurements are presented here. Measured thrust ranged from 17.2 mN to 30.4 mN over a discharge power of 280 W to 520 W with an anode Isp range of 870 s to 1450 s. Temperature limitations of materials used for the channel walls and propellant distributor limit the ability to run the thruster at thermal steady-state. While the current thruster design is not yet ready for continuous operation, revisions to the device that could enable longer duration tests are discussed.

  10. Opinions of Old Age According to Residents of Polish Public Nursing Homes and Members of the Universities of the Third Age.

    Science.gov (United States)

    Cybulski, Mateusz; Krajewska-Kułak, Elżbieta; Jamiołkowski, Jacek

    2016-01-01

    Statistical data from the turn of the 21st century shows a significant increase in the average human life span and, what follows, an extension of old age. The aim of this study was to become familiar with the opinions submitted by respondents regarding aging and old age, health problems connected with aging and preferred health behaviors. The research was conducted between January 3rd 2013 and February 15th 2014 on a group of 200 residents of public nursing homes and 200 members of the University of the Third Age using a questionnaire created by the authors. Forty-two point five per cent of the residents of PNHs and 58.0% of the members of UTAs were of the opinion that old age can be a successful period of life. Sixty-one percent of all participants stated that the elderly are needed in society. According to respondents, the factor which was most important in delaying aging was an active lifestyle (80.0% of residents of PNH vs. 90.0% of UTA members). Perceptions of elderly people by the seniors are different, complex and multidimensional. The perception of elderly people to society can variously affect (positively or negatively) quality of life in this age group. The results of the study showed small differences between the residents of public nursing homes and students of Universities of the Third Age in the perception of old age. There is a need to integrate seniors with younger generations in order to eliminate the stereotypes prevailing in society about older people.

  11. Resident perceptions of the educational value of night float rotations.

    Science.gov (United States)

    Luks, Andrew M; Smith, C Scott; Robins, Lynne; Wipf, Joyce E

    2010-07-01

    Night float rotations are being increasingly used in the era of resident physician work-hour regulations, but their impact on resident education is not clear. Our objective was to clarify resident perceptions of the educational aspects of night float rotations. An anonymous survey of internal medicine residents at a university-based residency program was completed. Responses were received from 116 of 163 surveyed residents (71%). Residents attended less residents' report (0.10 +/- .43 vs. 2.70 + 0.93 sessions/week, peducational value of night float, sleep cycle adjustment issues, and impact on their personal lives, which correlated with resident evaluations from the regular program evaluation process. In free responses, residents commented that they liked the autonomy and opportunity to improve triage skills on these rotations and confirmed their negative opinions about the sleep-wake cycle and interference with personal lives. Internal medicine residents at a university-based program have negative opinions regarding the educational value of night float rotations. Further work is necessary to determine whether problems exist across programs and specialties.

  12. Fast food consumption pattern and body weight status among ...

    African Journals Online (AJOL)

    The study assessed fast food consumption pattern (FFCP) and body weight status among the undergraduates of Obafemi Awolowo University, Ile-Ife, Nigeria, living in different halls of residence on the university campus during the Rain semester of 2011/2012 session. The study employed survey research design to give an ...

  13. L'effet Hall Quantique

    Science.gov (United States)

    Samson, Thomas

    Nous proposons une methode permettant d'obtenir une expression pour la conductivite de Hall de structures electroniques bidimensionnelles et nous examinons celle -ci a la limite d'une temperature nulle dans le but de verifier l'effet Hall quantique. Nous allons nous interesser essentiellement a l'effet Hall quantique entier et aux effets fractionnaires inferieurs a un. Le systeme considere est forme d'un gaz d'electrons en interaction faible avec les impuretes de l'echantillon. Le modele du gaz d'electrons consiste en un gaz bidimensionnel d'electrons sans spin expose perpendiculairement a un champ magnetique uniforme. Ce dernier est decrit par le potentiel vecteur vec{rm A} defini dans la jauge de Dingle ou jauge symetrique. Conformement au formalisme de la seconde quantification, l'hamiltonien de ce gaz est represente dans la base des etats a un-corps de Dingle |n,m> et exprime ainsi en terme des operateurs de creation et d'annihilation correspondants a_sp{ rm n m}{dag} et a _{rm n m}. Nous supposons de plus que les electrons du niveau fondamental de Dingle interagissent entre eux via le potentiel coulombien. La methode utilisee fait appel a une equation mai tresse a N-corps, de nature quantique et statistique, et verifiant le second principe de la thermodynamique. A partir de celle-ci, nous obtenons un systeme d'equations differentielles appele hierarchie d'equations quantique dont la resolution nous permet de determiner une equation a un-corps, dite de Boltzmann quantique, et dictant l'evolution de la moyenne statistique de l'operateur non-diagonal a _sp{rm n m}{dag } a_{rm n}, _{rm m}, sous l'action du champ electrique applique vec{rm E}(t). C'est sa solution Tr(p(t) a _sp{rm n m}{dag} a_{rm n},_ {rm m}), qui definit la relation de convolution entre la densite courant de Hall vec{rm J}_{rm H }(t) et le champ electrique vec {rm E}(t) dont la transformee de Laplace-Fourier du noyau nous fournit l'expression de la conductivite de Hall desiree. Pour une valeur de

  14. Association of General Surgery Resident Remediation and Program Director Attitudes With Resident Attrition.

    Science.gov (United States)

    Schwed, Alexander C; Lee, Steven L; Salcedo, Edgardo S; Reeves, Mark E; Inaba, Kenji; Sidwell, Richard A; Amersi, Farin; Are, Chandrakanth; Arnell, Tracey D; Damewood, Richard B; Dent, Daniel L; Donahue, Timothy; Gauvin, Jeffrey; Hartranft, Thomas; Jacobsen, Garth R; Jarman, Benjamin T; Melcher, Marc L; Mellinger, John D; Morris, Jon B; Nehler, Mark; Smith, Brian R; Wolfe, Mary; Kaji, Amy H; de Virgilio, Christian

    2017-12-01

    Previous studies of resident attrition have variably included preliminary residents and likely overestimated categorical resident attrition. Whether program director attitudes affect attrition has been unclear. To determine whether program director attitudes are associated with resident attrition and to measure the categorical resident attrition rate. This multicenter study surveyed 21 US program directors in general surgery about their opinions regarding resident education and attrition. Data on total resident complement, demographic information, and annual attrition were collected from the program directors for the study period of July 1, 2010, to June 30, 2015. The general surgery programs were chosen on the basis of their geographic location, previous collaboration with some coauthors, prior work in surgical education and research, or a program director willing to participate. Only categorical surgical residents were included in the study; thus, program directors were specifically instructed to exclude any preliminary residents in their responses. Five-year attrition rates (2010-2011 to 2014-2015 academic years) as well as first-time pass rates on the General Surgery Qualifying Examination and General Surgery Certifying Examination of the American Board of Surgery (ABS) were collected. High- and low-attrition programs were compared. The 21 programs represented different geographic locations and 12 university-based, 3 university-affiliated, and 6 independent program types. Programs had a median (interquartile range [IQR]) number of 30 (20-48) categorical residents, and few of those residents were women (median [IQR], 12 [5-17]). Overall, 85 of 966 residents (8.8%) left training during the study period: 15 (17.6%) left after postgraduate year 1, 34 (40.0%) after postgraduate year 2, and 36 (42.4%) after postgraduate year 3 or later. Forty-four residents (51.8%) left general surgery for another surgical discipline, 21 (24.7%) transferred to a different surgery

  15. Assessment of pediatric residents burnout in a tertiary academic centre

    Directory of Open Access Journals (Sweden)

    Roaa S. Jamjoom

    2018-03-01

    Full Text Available Objectives: To study burnout among pediatric residents at King Abdulazaiz University Hospital in Jeddah, Saudi Arabia. Methods: This is a cross-sectional survey that was administered to all pediatric residents enrolled in the Saudi Paediatric Board program (PGY1-PGY4 in a large tertiary academic hospital in the Western region of Saudi Arabia (King Abdulaziz University Hospital. The survey were sent via E-mail to 50 registered general pediatric residents. Results: Seventy percent of the pediatric residents completed the survey. More than 70% of residents experiencing severe burnout. Forty-three percent suffering emotional exhaustion, 71.8% experiencing depersonalization and 40.6% suffering from low accomplishment. Conclusion: Burnout syndrome appear to be a serious threat to resident well-being in our program. Moreover, pediatric residents in our institute experienced higher levels of depersonalization than their peers nationally and internationally.

  16. Piezo Voltage Controlled Planar Hall Effect Devices.

    Science.gov (United States)

    Zhang, Bao; Meng, Kang-Kang; Yang, Mei-Yin; Edmonds, K W; Zhang, Hao; Cai, Kai-Ming; Sheng, Yu; Zhang, Nan; Ji, Yang; Zhao, Jian-Hua; Zheng, Hou-Zhi; Wang, Kai-You

    2016-06-22

    The electrical control of the magnetization switching in ferromagnets is highly desired for future spintronic applications. Here we report on hybrid piezoelectric (PZT)/ferromagnetic (Co2FeAl) devices in which the planar Hall voltage in the ferromagnetic layer is tuned solely by piezo voltages. The change of planar Hall voltage is associated with magnetization switching through 90° in the plane under piezo voltages. Room temperature magnetic NOT and NOR gates are demonstrated based on the piezo voltage controlled Co2FeAl planar Hall effect devices without the external magnetic field. Our demonstration may lead to the realization of both information storage and processing using ferromagnetic materials.

  17. Supplementing Resident Research Funding Through a Partnership With Local Industry.

    Science.gov (United States)

    Skube, Steven J; Arsoniadis, Elliot G; Jahansouz, Cyrus; Novitsky, Sherri; Chipman, Jeffrey G

    2018-01-17

    To develop a model for the supplementation of resident research funding through a resident-hosted clinical immersion with local industry. Designated research residents hosted multiple groups of engineers and business professionals from local industry in general surgery-focused clinical immersion weeks. The participants in these week-long programs are educated about general surgery and brought to the operating room to observe a variety of surgeries. This study was performed at the University of Minnesota, in Minneapolis, Minnesota, at a tertiary medical center. Ten designated research residents hosted general surgery immersion programs. Fifty-seven engineers and business professionals from 5 different local biomedical firms have participated in this program. General surgery research residents (in collaboration with the University of Minnesota's Institute for Engineering in Medicine) have hosted 9 clinical immersion programs since starting the collaborative in 2015. Immersion participant response to the experiences was very positive. Two full-time resident research positions can be funded annually through participation in this program. With decreasing funding available for surgical research, particularly resident research, innovative ways to fund resident research are needed. The general surgery clinical immersion program at the University of Minnesota has proven its value as a supplement for resident research funding and may be a sustainable model for the future. Copyright © 2018 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  18. Higher fractions theory of fractional hall effect

    International Nuclear Information System (INIS)

    Kostadinov, I.Z.; Popov, V.N.

    1985-07-01

    A theory of fractional quantum Hall effect is generalized to higher fractions. N-particle model interaction is used and the gap is expressed through n-particles wave function. The excitation spectrum in general and the mean field critical behaviour are determined. The Hall conductivity is calculated from first principles. (author)

  19. Prevalence of ADHD among the Students Residing in Dormitory of Ardabil University of Medical Sciences

    Directory of Open Access Journals (Sweden)

    Fariba Sadeghi Movahed

    2012-11-01

    Full Text Available Background & Objective: Attention Deficit-Hyperactivity Disorder (ADHD is a heredity and psychological disorder that often continues to adulthood and causes great number of emotional, social, educational and occupational problem for college students. The aim of this study is to determine the prevalence of ADHD among students residing in the dormitory of Ardabil University of Medical Sciences.   Methods: In this cross sectional study, all students in the dormitory of Ardabil University of Medical Sciences were included. They filled the Self reporting Conner’s ADHD questionnaires. Data were extracted and analyzed with SPSS.   Results: During this study, the prevalence of ADHD was 8.6 percent. The males show more involvement rate than females. The students with ADHD showed more incidences of smoking and psychotropic drug consumption.   Conclusion: Due to the high prevalence of ADHD among the college students, early diagnosis and treatment of ADHD seems to be necessary.

  20. Experimental test of 200 W Hall thruster with titanium wall

    Science.gov (United States)

    Ding, Yongjie; Sun, Hezhi; Peng, Wuji; Xu, Yu; Wei, Liqiu; Li, Hong; Li, Peng; Su, Hongbo; Yu, Daren

    2017-05-01

    We designed a 200 W Hall thruster based on the technology of pushing down a magnetic field with two permanent magnetic rings. Boron nitride (BN) is an important insulating wall material for Hall thrusters. The discharge characteristics of the designed Hall thruster were studied by replacing BN with titanium (Ti). Experimental results show that the designed Hall thruster can discharge stably for a long time under a Ti channel. Experiments were performed to determine whether the channel and cathode are electrically connected. When the channel wall and cathode are insulated, the divergence angle of the plume increases, but the performance of the Hall thruster is improved in terms of thrust, specific impulse, anode efficiency, and thrust-to-power ratio. Ti exhibits a powerful antisputtering capability, a low emanation rate of gas, and a large structural strength, making it a potential candidate wall material in the design of low-power Hall thrusters.

  1. 27 November 2013 - Greek Deputy Minister of Health Z. Makri with Governor of Thessaly K. Agorastos visiting the LHC superconducting magnet test hall with Senior Scientists D. Delikaris, E. Hatziangeli and E. Tsesmelis. E. Gazis, ATLAS Collaboration, National Technical University of Athens also present.

    CERN Multimedia

    Anna Pantelia

    2013-01-01

    27 November 2013 - Greek Deputy Minister of Health Z. Makri with Governor of Thessaly K. Agorastos visiting the LHC superconducting magnet test hall with Senior Scientists D. Delikaris, E. Hatziangeli and E. Tsesmelis. E. Gazis, ATLAS Collaboration, National Technical University of Athens also present.

  2. Composite fermions in the quantum Hall effect

    International Nuclear Information System (INIS)

    Johnson, B.L.; Kirczenow, G.

    1997-01-01

    The quantum Hall effect and associated quantum transport phenomena in low-dimensional systems have been the focus of much attention for more than a decade. Recent theoretical development of interesting quasiparticles - 'composite fermions' - has led to significant advances in understanding and predicting the behaviour of two-dimensional electron systems under high transverse magnetic fields. Composite fermions may be viewed as fermions carrying attached (fictitious) magnetic flux. Here we review models of the integer and fractional quantum Hall effects, including the development of a unified picture of the integer and fractional effects based upon composite fermions. The composite fermion picture predicts remarkable new physics: the formation of a Fermi surface at high magnetic fields, and anomalous ballistic transport, thermopower, and surface acoustic wave behaviour. The specific theoretical predictions of the model, as well as the body of experimental evidence for these phenomena are reviewed. We also review recent edge-state models for magnetotransport in low-dimensional devices based on the composite fermion picture. These models explain the fractional quantum Hall effect and transport phenomena in nanoscale devices in a unified framework that also includes edge state models of the integer quantum Hall effect. The features of the composite fermion edge-state model are compared and contrasted with those of other recent edge-state models of the fractional quantum Hall effect. (author)

  3. Magnetic Measurements of the Background Field in the Undulator Hall

    International Nuclear Information System (INIS)

    Fisher, Andrew

    2010-01-01

    The steel present in the construction of the undulator hall facility has the potential for changing the ambient fields present in the undulator hall. This note describes a measurement done to make a comparison between the fields in the hall and in the Magnetic Measurement Facility. In order for the undulators to have the proper tuning, the background magnetic field in the Undulator Hall should agree with the background field in the Magnetic Measurements Facility within .5 gauss. In order to verify that this was the case measurements were taken along the length of the undulator hall, and the point measurements were compared to the mean field which was measured on the MMF test bench.

  4. Magnesium Hall Thruster

    Science.gov (United States)

    Szabo, James J.

    2015-01-01

    This Phase II project is developing a magnesium (Mg) Hall effect thruster system that would open the door for in situ resource utilization (ISRU)-based solar system exploration. Magnesium is light and easy to ionize. For a Mars- Earth transfer, the propellant mass savings with respect to a xenon Hall effect thruster (HET) system are enormous. Magnesium also can be combusted in a rocket with carbon dioxide (CO2) or water (H2O), enabling a multimode propulsion system with propellant sharing and ISRU. In the near term, CO2 and H2O would be collected in situ on Mars or the moon. In the far term, Mg itself would be collected from Martian and lunar regolith. In Phase I, an integrated, medium-power (1- to 3-kW) Mg HET system was developed and tested. Controlled, steady operation at constant voltage and power was demonstrated. Preliminary measurements indicate a specific impulse (Isp) greater than 4,000 s was achieved at a discharge potential of 400 V. The feasibility of delivering fluidized Mg powder to a medium- or high-power thruster also was demonstrated. Phase II of the project evaluated the performance of an integrated, highpower Mg Hall thruster system in a relevant space environment. Researchers improved the medium power thruster system and characterized it in detail. Researchers also designed and built a high-power (8- to 20-kW) Mg HET. A fluidized powder feed system supporting the high-power thruster was built and delivered to Busek Company, Inc.

  5. A 15-year review of the Stanford Internal Medicine Residency Program: predictors of resident satisfaction and dissatisfaction

    Directory of Open Access Journals (Sweden)

    Kahn JS

    2017-08-01

    Full Text Available James S Kahn,1–3 Ronald M Witteles,3,4 Kenneth W Mahaffey,3–5 Sumbul A Desai,2,3 Errol Ozdalga,2,3 Paul A Heidenreich1,3 1Veterans Affairs Palo Alto Health Care System, Palo Alto, 2Division of Primary Care and Population Health, 3Department of Medicine, 4Division of Cardiovascular Medicine, 5Stanford Center for Clinical Research, Stanford University School of Medicine, Stanford, CA, USA Introduction: Satisfaction with training and with educational experiences represents important internal medicine (IM programmatic goals. Graduates from IM residency programs are uniquely poised to provide insights into their educational and training experiences and to assess whether these experiences were satisfactory and relevant to their current employment. Methods: We surveyed former IM residents from the training program held during the years 2000–2015 at the Department of Medicine, Stanford University. The first part of the survey reviewed the IM residency program and the second part sought identifying data regarding gender, race, ethnicity, work, relationships, and financial matters. The primary outcome was satisfaction with the residency experience. Results: Of the 405 individuals who completed the Stanford IM residency program in the study period, we identified 384 (95% former residents with a known email address. Two hundred and one (52% former residents responded to the first part and 185 (48% answered both the parts of the survey. The mean age of the respondents was 36.9 years; 44% were female and the mean time from IM residency was 6.1 (±4.3 years. Fifty-eight percent reported extreme satisfaction with their IM residency experience. Predictors associated with being less than extremely satisfied included insufficient outpatient experience, insufficient international experience, insufficient clinical research experience, and insufficient time spent with family and peers. Conclusion: The residents expressed an overall high satisfaction rate with

  6. Emotional intelligence and its correlation to performance as a resident: a preliminary study.

    Science.gov (United States)

    Talarico, Joseph F; Metro, David G; Patel, Rita M; Carney, Patricia; Wetmore, Amy L

    2008-03-01

    To test the hypothesis that emotional intelligence, as measured by the Bar-On Emotional Quotient Inventory (EQ-I) 125 (Multi Health Systems, Toronto, Ontario, Canada) personal inventory, would correlate with resident performance. Prospective survey. University-affiliated, multiinstitutional anesthesiology residency program. Current clinical anesthesiology years one to three (PGY 2-4) anesthesiology residents enrolled in the University of Pittsburgh Anesthesiology Residency Program. Participants confidentially completed the Bar-On EQ-I 125 survey. Results of the individual EQ-I 125 and daily evaluations by the faculty of the residency program were compiled and analyzed. There was no positive correlation between any facet of emotional intelligence and resident performance. There was statistically significant negative correlation (-0.40; P Emotional intelligence, as measured by the Bar-On EQ-I personal inventory, does not strongly correlate to resident performance as defined at the University of Pittsburgh.

  7. Trends in preference, programming and design of concert halls for symphonic music

    DEFF Research Database (Denmark)

    Gade, Anders Christian

    2008-01-01

    This paper discusses the evolution in taste regarding concert hall acoustics and how this can be reflected in the new halls being built today. The clients' and listener's preferences are not only based on listening in existing halls; but also on listening to reproduced music recorded with microph......This paper discusses the evolution in taste regarding concert hall acoustics and how this can be reflected in the new halls being built today. The clients' and listener's preferences are not only based on listening in existing halls; but also on listening to reproduced music recorded...

  8. Facebook Use between College Resident Advisors' and Their Residents: A Mixed Methods Approach.

    Science.gov (United States)

    Kacvinsky, Lauren E; Moreno, Megan A

    2014-01-01

    Facebook use is nearly ubiquitous among college students. Studies have shown links between Facebook displays of depression or problem drinking and risk of these problems. This project aimed to determine whether Facebook could be used to help Resident Advisors (RAs) identify college students at risk for depression or problem drinking. Interviews were conducted with college freshmen to investigate whether they were Facebook "friends" with their RA. Focus groups were conducted with RAs to determine their views on Facebook friending their dormitory residents and using Facebook to help identify at-risk students. 72 freshmen were interviewed and 25 RAs participated in focus groups; both agreed it is common for RAs and residents to be Facebook friends. RAs commonly noted references to depression and problem drinking on residents' Facebook pages, which often led to in-person discussions with the resident. This study provides support that RAs use Facebook to identify issues that may impact their student residents. RAs emphasized benefits of in-person interactions in order to provide support and obtain additional details about the situation. Universities could consider whether providing RA education about Facebook interactions with residents merits encouragement within their existing RA training programs.

  9. Hall effect in organic layered conductors

    Directory of Open Access Journals (Sweden)

    R.A.Hasan

    2006-01-01

    Full Text Available The Hall effect in organic layered conductors with a multisheeted Fermi surfaces was considered. It is shown that the experimental study of Hall effect and magnetoresistance anisotropy at different orientations of current and a quantizing magnetic field relative to the layers makes it possible to determine the contribution of various charge carriers groups to the conductivity, and to find out the character of Fermi surface anisotropy in the plane of layers.

  10. Tunnelling anomalous and planar Hall effects (Conference Presentation)

    Science.gov (United States)

    Matos-Abiague, Alex; Scharf, Benedikt; Han, Jong E.; Hankiewicz, Ewelina M.; Zutic, Igor

    2016-10-01

    We theoretically show how the interplay between spin-orbit coupling (SOC) and magnetism can result in a finite tunneling Hall conductance, transverse to the applied bias. For two-dimensional tunnel junctions with a ferromagnetic lead and magnetization perpendicular to the current flow, the detected anomalous Hall voltage can be used to extract information not only about the spin polarization but also about the strength of the interfacial SOC. In contrast, a tunneling current across a ferromagnetic barrier on the surface of a three-dimensional topological insulator (TI) can induce a planar Hall response even when the magnetization is oriented along the current flow[1]. The tunneling nature of the states contributing to the planar Hall conductance can be switched from the ordinary to the Klein regimes by the electrostatic control of the barrier strength. This allows for an enhancement of the transverse response and a giant Hall angle, with the tunneling planar Hall conductance exceeding the longitudinal component. Despite the simplicity of a single ferromagnetic region, the TI/ferromagnet system exhibits a variety of functionalities. In addition to a spin-valve operation for magnetic sensing and storing information, positive, negative, and negative differential conductances can be tuned by properly adjusting the barrier potential and/or varying the magnetization direction. Such different resistive behaviors in the same system are attractive for potential applications in reconfigurable spintronic devices. [1] B. Scharf, A. Matos-Abiague, J. E. Han, E. M. Hankiewicz, and I. Zutic, arXiv:1601.01009 (2016).

  11. Shielding consideration for the SSCL experimental halls

    International Nuclear Information System (INIS)

    Bull, J.; Coyne, J.; Mokhov, N.; Stapleton, G.

    1994-03-01

    The Superconducting Super Collider which is being designed and built in Waxahachie, Texas consists Of series of proton accelerators, culminating in a 20 Te proton on proton collider. The collider will be in a tunnel which will be 87 km in circumference and. on average about 30 meters underground. The present design calls for two large interaction halls on the east side of the ring. The shielding for these halls is being designed for an interaction rate of 10 9 Hz or 10 16 interactions per year, based on 10 7 seconds per operational year. SSC guidelines require that the shielding be designed to meet the criterion of 1mSv per year for open areas off site 2mSv per year for open areas on site, and 2mSv per year for controlled areas. Only radiation workers will be routinely allowed to work in controlled areas. It should be pointed that there is a potential for an accidental full beam loss in either of the experimental halls, and this event would consist of the loss of the full circulating beam up to 4 x 10 14 protons. With the present design. the calculated dose equivalent for this event is about 10% of the annual dose equivalent for the normal p-p interactions, so that die accident condition does not control the shielding. If, for instance, local shielding within the experimental hall is introduced into the calculations, this could change. The shielding requirements presented here are controlled by the normal p-p interactions. Three important questions were addressed in the present calculations. They are (1) the thickness of the roof over the experimental halls, (2) the configuration of the shafts and adits which give access to the halls, and (3) the problem of ground water and air activation

  12. Precision of single-engage micro Hall effect measurements

    DEFF Research Database (Denmark)

    Henrichsen, Henrik Hartmann; Hansen, Ole; Kjær, Daniel

    2014-01-01

    Recently a novel microscale Hall effect measurement technique has been developed to extract sheet resistance (RS), Hall sheet carrier density (NHS) and Hall mobility (μH) from collinear micro 4-point probe measurements in the vicinity of an insulating boundary [1]. The technique measures in less...... than a minute directly the local transport properties, which enables in-line production monitoring on scribe line test pads [2]. To increase measurement speed and reliability, a method in which 4-point measurements are performed using two different electrode pitches has been developed [3......]. In this study we calculate the measurement error on RS, NHS and μH resulting from electrode position errors, probe placement, sample size and Hall signal magnitude. We show the relationship between measurement precision and electrode pitch, which is important when down-scaling the micro 4-point probe to fit...

  13. Resident assistant training program for increasing alcohol, other drug, and mental health first-aid efforts.

    Science.gov (United States)

    Thombs, Dennis L; Gonzalez, Jennifer M Reingle; Osborn, Cynthia J; Rossheim, Matthew E; Suzuki, Sumihiro

    2015-05-01

    In college and university residence halls, resident assistants (RAs) are expected to serve as first-aid providers to students who may have alcohol, other drug, mental health, and academic problems. Despite this responsibility, evidence-based, first-aid programs have not been developed and tested for the RA workforce. The current study examined effects of an investigational first-aid program designed specifically for RAs. The online Peer Hero Training program is a novel approach to RA training in its use of interactive video dramatizations of incidents involving substance-using or distressed residents. A 9-month randomized trial conducted on eight US campuses compared RAs who participated in the Peer Hero Training program to RAs who received training-as-usual. Participation in the Peer Hero Training program significantly increased RA first-aid efforts for residential students who may have had alcohol, other drug, mental health, or academic problems 6 months after baseline. Compared with those in the training-as-usual condition, RAs in the Peer Hero Training program made more than 10 times as many first-aid efforts for possible alcohol problems, almost 14 times the number of first-aid efforts for possible drug use, almost 3 times the number of first-aid efforts for possible mental health problems, and 3 times the number of first-aid efforts for academic problems. There was no evidence that measured RA attitudes mediated the effects of the intervention. Results of this preliminary evaluation trial suggest that online training using interactive video dramatizations is a viable approach to strengthening RAs' ability to provide alcohol, other drugs, and mental health first-aid to undergraduates.

  14. Feasibility of an innovative third-year chief resident system: an internal medicine residency leadership study

    Directory of Open Access Journals (Sweden)

    Victor O. Kolade

    2014-07-01

    Full Text Available Introduction: The role of the internal medicine chief resident includes various administrative, academic, social, and educational responsibilities, fulfillment of which prepares residents for further leadership tasks. However, the chief resident position has historically only been held by a few residents. As fourth-year chief residents are becoming less common, we considered a new model for rotating third-year residents as the chief resident. Methods: Online surveys were given to all 29 internal medicine residents in a single university-based program after implementation of a leadership curriculum and specific job description for the third-year chief resident. Chief residents evaluated themselves on various aspects of leadership. Participation was voluntary. Descriptive statistics were generated using SPSS version 21. Results: Thirteen junior (first- or second-year resident responses reported that the chief residents elicited input from others (mean rating 6.8, were committed to the team (6.8, resolved conflict (6.7, ensured efficiency, organization and productivity of the team (6.7, participated actively (7.0, and managed resources (6.6. Responses from senior residents averaged 1 point higher for each item; this pattern repeated itself in teaching evaluations. Chief resident self-evaluators were more comfortable running a morning report (8.4 than with being chief resident (5.8. Conclusion: The feasibility of preparing internal medicine residents for leadership roles through a rotating PGY-3 (postgraduate year chief residency curriculum was explored at a small internal medicine residency, and we suggest extending the study to include other programs.

  15. Observation of the anomalous Hall effect in GaAs

    International Nuclear Information System (INIS)

    Miah, M Idrish

    2007-01-01

    Devices for the direct detection of the spin current, based on the anomalous Hall effect (AHE), are fabricated on n-type GaAs bulk semiconductor materials. The AHE is observed in the device when the photoinduced spin-polarized electrons are injected into it, and it is found that the effect depends on the applied electric field. The origin of the field-dependent observed Hall effect is discussed based on the D'yakonov-Perel' (DP) spin relaxation mechanism. The spin-dependent Hall effect is also found to be enhanced with increasing doping concentration. The present experimental results might have potential applications in semiconductor spintronic devices since the effect is closely related to the spin Hall effect

  16. Observation of the anomalous Hall effect in GaAs

    Energy Technology Data Exchange (ETDEWEB)

    Miah, M Idrish [Nanoscale Science and Technology Centre, School of Science, Griffith University, Nathan, Brisbane, QLD 4111 (Australia); Department of Physics, University of Chittagong, Chittagong, Chittagong - 4331 (Bangladesh)

    2007-03-21

    Devices for the direct detection of the spin current, based on the anomalous Hall effect (AHE), are fabricated on n-type GaAs bulk semiconductor materials. The AHE is observed in the device when the photoinduced spin-polarized electrons are injected into it, and it is found that the effect depends on the applied electric field. The origin of the field-dependent observed Hall effect is discussed based on the D'yakonov-Perel' (DP) spin relaxation mechanism. The spin-dependent Hall effect is also found to be enhanced with increasing doping concentration. The present experimental results might have potential applications in semiconductor spintronic devices since the effect is closely related to the spin Hall effect.

  17. Stress and burnout among Swiss dental residents

    OpenAIRE

    Divaris, Kimon; Lai, Caroline S; Polychronopoulou, Argy; Eliades, Theodore; Katsaros, Christos

    2012-01-01

    Stress and burnout have been well-documented in graduate medical and undergraduate dental education, but studies among dental graduate students and residents are sparse. The purpose of this investigation was to examine perceived stressors and three dimensions of burnout among dental residents enrolled in the University of Bern, Switzerland. Thirty-six residents enrolled in five specialty programmes were administered the Graduate Dental Environment Stress (GDES30) questionnaire and the Maslach...

  18. Quantum Hall Ferroelectrics and Nematics in Multivalley Systems

    Science.gov (United States)

    Sodemann, Inti; Zhu, Zheng; Fu, Liang

    2017-10-01

    We study broken symmetry states at integer Landau-level fillings in multivalley quantum Hall systems whose low-energy dispersions are anisotropic. When the Fermi surface of individual pockets lacks twofold rotational symmetry, like in bismuth (111) [Feldman et al. , Observation of a Nematic Quantum Hall Liquid on the Surface of Bismuth, Science 354, 316 (2016), 10.1126/science.aag1715] and in Sn1 -xPbxSe (001) [Dziawa et al., Topological Crystalline Insulator States in Pb1 -xSnxSe , Nat. Mater. 11, 1023 (2012), 10.1038/nmat3449] surfaces, interactions tend to drive the formation of quantum Hall ferroelectric states. We demonstrate that the dipole moment in these states has an intimate relation to the Fermi surface geometry of the parent metal. In quantum Hall nematic states, like those arising in AlAs quantum wells, we demonstrate the existence of unusually robust Skyrmion quasiparticles.

  19. A Novel Hall Effect Sensor Using Elaborate Offset Cancellation Method

    Directory of Open Access Journals (Sweden)

    Vlassis N. Petoussis

    2009-01-01

    Full Text Available The Hall effect is caused by a traverse force that is formed in the electrons or holes of metal element or semiconductor when are polarized by current source and simultaneously all the system it is found vertical in external magnetic field. Result is finally the production of difference of potential (Hall voltage in address vertical in that of current and magnetic field directions. In the present work is presented a new Hall sensor exploiting the former operation. In combination with his pioneering form and using dynamic spinning current technique with an elaborate sequence, it leads to satisfactory results of produced Hall voltage with small noise in a presence of external magnetic field. Anyone can see both the spinning current and anti-Hall technique in the same sensor simultaneously.

  20. Digital technology impacts on the Arnhem transfer hall structural design

    NARCIS (Netherlands)

    Van de Straat, R.; Hofman, S.; Coenders, J.L.; Paul, J.C.

    2015-01-01

    The new Transfer Hall in Arnhem is one of the key projects to prepare the Dutch railways for the increased future demands for capacity. UNStudio developed a master plan in 1996 for the station area of which the completion of the Transfer Hall in 2015 will be a final milestone. The Transfer Hall is a

  1. Acoustic investigations of concert halls for rock music

    DEFF Research Database (Denmark)

    Adelman-Larsen, Niels Werner; Thompson, Eric Robert; Gade, Anders Christian

    2007-01-01

    Objective measurement data and subjective evaluations have been collected from 20 small-/medium-sized halls in Denmark used for amplified rhythmic music concerts (pop, rock, jazz). The purpose of the study was to obtain knowledge about optimum acoustic conditions for this type of hall. The study...... is motivated by the fact that most concert tickets sold in Denmark relate to concerts within these genres in this kind of venue. The subjective evaluations were carried out by professional musicians and sound engineers who responded on the basis of their experiences working in these (and other) halls. From...

  2. Magnetohydrodynamic simulations of Gamble I POS with Hall effect

    International Nuclear Information System (INIS)

    Roderick, N.F.; Frese, M.H.; Peterkin, R.E.; Payne, S.S.

    1989-01-01

    Two dimensional single fluid magnetohydrodynamic simulations have been conducted to investigate the effects of the Hall electric field on magnetic field transport in plasma opening switches of the type used on Gamble I. The Hall terms were included in the magnetic field transport equation in the two dimensional simulation code MACH2 through the use of a generalized Ohm's law. Calculations show the Hall terms augment the field transport previously observed to occur through ion fluid motion and diffusion. For modest values of microturbulent collision frequency, board current channels were observed . Results also show the magnetic field transport to be affected by the cathode boundary conditions with the Hall terms included. In all cases center of mass motion was slight

  3. Quantum critical behaviour of the plateau-insulator transition in the quantum Hall regime

    International Nuclear Information System (INIS)

    Visser, A de; Ponomarenko, L A; Galistu, G; Lang, D T N de; Pruisken, A M M; Zeitler, U; Maude, D

    2006-01-01

    High-field magnetotransport experiments provide an excellent tool to investigate the plateau-insulator phase transition in the integral quantum Hall effect. Here we review recent low-temperature high-field magnetotransport studies carried out on several InGaAs/InP heterostructures and an InGaAs/GaAs quantum well. We find that the longitudinal resistivity ρ xx near the critical filling factor ν c ∼ 0.5 follows the universal scaling law ρ xx (ν, T) ∝ exp(-Δν/(T/T 0 ) κ ), where Δν = ν-ν c . The critical exponent κ equals 0.56 ± 0.02, which indicates that the plateau-insulator transition falls in a non-Fermi liquid universality class

  4. Spin Hall effect on a noncommutative space

    International Nuclear Information System (INIS)

    Ma Kai; Dulat, Sayipjamal

    2011-01-01

    We study the spin-orbital interaction and the spin Hall effect of an electron moving on a noncommutative space under the influence of a vector potential A(vector sign). On a noncommutative space, we find that the commutator between the vector potential A(vector sign) and the electric potential V 1 (r(vector sign)) of the lattice induces a new term, which can be treated as an effective electric field, and the spin Hall conductivity obtains some correction. On a noncommutative space, the spin current and spin Hall conductivity have distinct values in different directions, and depend explicitly on the noncommutative parameter. Once this spin Hall conductivity in different directions can be measured experimentally with a high level of accuracy, the data can then be used to impose bounds on the value of the space noncommutativity parameter. We have also defined a new parameter, σ=ρθ (ρ is the electron concentration, θ is the noncommutativity parameter), which can be measured experimentally. Our approach is based on the Foldy-Wouthuysen transformation, which gives a general Hamiltonian of a nonrelativistic electron moving on a noncommutative space.

  5. An examination of mobbing and burnout of residents.

    Science.gov (United States)

    Dikmetaş, Elif; Top, Mehmet; Ergin, Gülpembe

    2011-01-01

    Mobbing and burnout in human resources management are important topics in labor psychology. It is important to research the levels of mobbing and burnout of human resources in the health sector, primarily in doctors. Although there have been some studies on the mobbing and burnout of doctors, there has been a limited number of studies on the relationship between mobbing and burnout in the health sector. This study aims to examine the relationship between mobbing and burnout (emotional exhaustion, depersonalization, personal accomplishment) levels of resident doctors at a public university research and training hospital in Turkey and to investigate whether mobbing and burnout levels vary significantly according to gender, marital status, medical branch and age. This study was conducted on resident doctors at the Ondokuz Mayıs University Research and Training Hospital between 01.04.2009 and 30.06.2009. Legal permission for the study was received from the Rector's Office of Ondokuz Mayıs University. The Maslach Burnout Inventory for measuring burnout levels in doctors and the Leymann Inventory of Psychological Terror for measuring doctors' mobbing levels were the research instruments employed. Sampling was not used in this study. The aim was to administer the research instruments to all the residents (the universe of this study consisted of 510 assistant doctors). 52.94 % of residents responded to all of the questions in these instruments. In the data analysis, a t-test, ANOVA, regression analysis and descriptive statistics were used. At the end of the analyses, it was found that the mean mobbing level of residents is 1.97; the mean emotional exhaustion level of residents is 2.97; the mean level of depersonalization is 2.95; and the mean level of personal accomplishment is 2.94. Mobbing and burnout levels of residents vary significantly in terms of medical branch. This study indicated that there are relationships between mobbing, emotional exhaustion

  6. Hole mobilities and the effective Hall factor in p-type GaAs

    Science.gov (United States)

    Wenzel, M.; Irmer, G.; Monecke, J.; Siegel, W.

    1997-06-01

    We prove the effective Hall factor in p-GaAs to be larger than values discussed in the literature up to now. The scattering rates for the relevant scattering mechanisms in p-GaAs have been recalculated after critical testing the existing models. These calculations allow to deduce theoretical drift and theoretical Hall mobilities as functions of temperature which can be compared with measured data. Theoretical Hall factors in the heavy and light hole bands and an effective Hall factor result. The calculated room temperature values of the drift mobility and of the effective Hall factor are 118 cm2/V s and 3.6, respectively. The fitted acoustic deformation potential E1=7.9 eV and the fitted optical coupling constant DK=1.24×1011 eV/m are close to values published before. It is shown that the measured strong dependence of the Hall mobility on the Hall concentration is not mainly caused by scattering by ionized impurities but by the dependence of the effective Hall factor on the hole concentration.

  7. Goals and Methodology for a Surgery Residency Program: A Committee Approach.

    Science.gov (United States)

    Knecht, Charles D.; And Others

    1979-01-01

    Written goals of a small animal residency program established by Purdue University are identified and an elaborate list of methodology for goals is provided. Tables include: summary of required activities of residents, checklist of residency progress, and comparable effort for surgery residency and masters program. (Author/MLW)

  8. Field theory approach to quantum hall effect

    International Nuclear Information System (INIS)

    Cabo, A.; Chaichian, M.

    1990-07-01

    The Fradkin's formulation of statistical field theory is applied to the Coulomb interacting electron gas in a magnetic field. The electrons are confined to a plane in normal 3D-space and also interact with the physical 3D-electromagnetic field. The magnetic translation group (MTG) Ward identities are derived. Using them it is shown that the exact electron propagator is diagonalized in the basis of the wave functions of the free electron in a magnetic field whenever the MTG is unbroken. The general tensor structure of the polarization operator is obtained and used to show that the Chern-Simons action always describes the Hall effect properties of the system. A general proof of the Streda formula for the Hall conductivity is presented. It follows that the coefficient of the Chern-Simons terms in the long-wavelength approximation is exactly given by this relation. Such a formula, expressing the Hall conductivity as a simple derivative, in combination with diagonal form of the full propagator allows to obtain a simple expressions for the filling factor and the Hall conductivity. Indeed, these results, after assuming that the chemical potential lies in a gap of the density of states, lead to the conclusion that the Hall conductivity is given without corrections by σ xy = νe 2 /h where ν is the filling factor. In addition it follows that the filling factor is independent of the magnetic field if the chemical potential remains in the gap. (author). 21 ref, 1 fig

  9. Nontrivial transition of transmission in a highly open quantum point contact in the quantum Hall regime

    Science.gov (United States)

    Hong, Changki; Park, Jinhong; Chung, Yunchul; Choi, Hyungkook; Umansky, Vladimir

    2017-11-01

    Transmission through a quantum point contact (QPC) in the quantum Hall regime usually exhibits multiple resonances as a function of gate voltage and high nonlinearity in bias. Such behavior is unpredictable and changes sample by sample. Here, we report the observation of a sharp transition of the transmission through an open QPC at finite bias, which was observed consistently for all the tested QPCs. It is found that the bias dependence of the transition can be fitted to the Fermi-Dirac distribution function through universal scaling. The fitted temperature matches quite nicely to the electron temperature measured via shot-noise thermometry. While the origin of the transition is unclear, we propose a phenomenological model based on our experimental results that may help to understand such a sharp transition. Similar transitions are observed in the fractional quantum Hall regime, and it is found that the temperature of the system can be measured by rescaling the quasiparticle energy with the effective charge (e*=e /3 ). We believe that the observed phenomena can be exploited as a tool for measuring the electron temperature of the system and for studying the quasiparticle charges of the fractional quantum Hall states.

  10. Improving Clinical Feedback to Anesthesia Residents by Using an Optical Scanner and a Microcomputer.

    Science.gov (United States)

    Albanese, Mark A.; And Others

    1989-01-01

    At the University of Iowa problems associated with managing evaluations of anesthesia residents led to a major backlog of unanalyzed evaluation forms. A system developed at the University that enables ongoing feedback to residents and provides a method to assess the clinical competence of residents is described. (Author/MLW)

  11. Are quantum spin Hall edge modes more resilient to disorder, sample geometry and inelastic scattering than quantum Hall edge modes?

    Science.gov (United States)

    Mani, Arjun; Benjamin, Colin

    2016-04-13

    On the surface of 2D topological insulators, 1D quantum spin Hall (QSH) edge modes occur with Dirac-like dispersion. Unlike quantum Hall (QH) edge modes, which occur at high magnetic fields in 2D electron gases, the occurrence of QSH edge modes is due to spin-orbit scattering in the bulk of the material. These QSH edge modes are spin-dependent, and chiral-opposite spins move in opposing directions. Electronic spin has a larger decoherence and relaxation time than charge. In view of this, it is expected that QSH edge modes will be more robust to disorder and inelastic scattering than QH edge modes, which are charge-dependent and spin-unpolarized. However, we notice no such advantage accrues in QSH edge modes when subjected to the same degree of contact disorder and/or inelastic scattering in similar setups as QH edge modes. In fact we observe that QSH edge modes are more susceptible to inelastic scattering and contact disorder than QH edge modes. Furthermore, while a single disordered contact has no effect on QH edge modes, it leads to a finite charge Hall current in the case of QSH edge modes, and thus a vanishing of the pure QSH effect. For more than a single disordered contact while QH states continue to remain immune to disorder, QSH edge modes become more susceptible--the Hall resistance for the QSH effect changes sign with increasing disorder. In the case of many disordered contacts with inelastic scattering included, while quantization of Hall edge modes holds, for QSH edge modes a finite charge Hall current still flows. For QSH edge modes in the inelastic scattering regime we distinguish between two cases: with spin-flip and without spin-flip scattering. Finally, while asymmetry in sample geometry can have a deleterious effect in the QSH case, it has no impact in the QH case.

  12. Are quantum spin Hall edge modes more resilient to disorder, sample geometry and inelastic scattering than quantum Hall edge modes?

    International Nuclear Information System (INIS)

    Mani, Arjun; Benjamin, Colin

    2016-01-01

    On the surface of 2D topological insulators, 1D quantum spin Hall (QSH) edge modes occur with Dirac-like dispersion. Unlike quantum Hall (QH) edge modes, which occur at high magnetic fields in 2D electron gases, the occurrence of QSH edge modes is due to spin–orbit scattering in the bulk of the material. These QSH edge modes are spin-dependent, and chiral-opposite spins move in opposing directions. Electronic spin has a larger decoherence and relaxation time than charge. In view of this, it is expected that QSH edge modes will be more robust to disorder and inelastic scattering than QH edge modes, which are charge-dependent and spin-unpolarized. However, we notice no such advantage accrues in QSH edge modes when subjected to the same degree of contact disorder and/or inelastic scattering in similar setups as QH edge modes. In fact we observe that QSH edge modes are more susceptible to inelastic scattering and contact disorder than QH edge modes. Furthermore, while a single disordered contact has no effect on QH edge modes, it leads to a finite charge Hall current in the case of QSH edge modes, and thus a vanishing of the pure QSH effect. For more than a single disordered contact while QH states continue to remain immune to disorder, QSH edge modes become more susceptible—the Hall resistance for the QSH effect changes sign with increasing disorder. In the case of many disordered contacts with inelastic scattering included, while quantization of Hall edge modes holds, for QSH edge modes a finite charge Hall current still flows. For QSH edge modes in the inelastic scattering regime we distinguish between two cases: with spin-flip and without spin-flip scattering. Finally, while asymmetry in sample geometry can have a deleterious effect in the QSH case, it has no impact in the QH case. (paper)

  13. Performance Comparison of Cross-Like Hall Plates with Different Covering Layers

    Directory of Open Access Journals (Sweden)

    Fei Lyu

    2014-12-01

    Full Text Available This paper studies the effects of the covering layers on the performance of a cross-like Hall plate. Three different structures of a cross-like Hall plate in various sizes are designed and analyzed. The Hall plate sensitivity and offset are characterized using a self-built measurement system. The effect of the P-type region over the active area on the current-related sensitivity is studied for different Hall plate designs. In addition, the correlation between the P-type covering layer and offset is analyzed. The best structure out of three designs is determined. Besides, a modified eight-resistor circuit model for the Hall plate is presented with improved accuracy by taking the offset into account.

  14. Enhanced Performance of Cylindrical Hall Thrusters

    International Nuclear Information System (INIS)

    Raitses, Y.; Smirnov, A.; Fisch, N.J.

    2007-01-01

    The cylindrical thruster differs significantly in its underlying physical mechanisms from the conventional annular Hall thruster. It features high ionization efficiency, quiet operation, ion acceleration in a large volume-to-surface ratio channel, and performance comparable with the state-of-the-art conventional Hall thrusters. Very significant plume narrowing, accompanied by the increase of the energetic ion fraction and improvement of ion focusing, led to 50-60% increase of the thruster anode efficiency. These improvements were achieved by overrunning the discharge current in the magnetized thruster plasma

  15. Theory of fractional quantum Hall effect

    International Nuclear Information System (INIS)

    Kostadinov, I.Z.

    1984-09-01

    A theory of the fractional quantum Hall effect is constructed by introducing 3-particle interactions breaking the symmetry for ν=1/3 according to a degeneracy theorem proved here. An order parameter is introduced and a gap in the single particle spectrum is found. The critical temperature, critical filling number and critical behaviour are determined as well as the Ginzburg-Landau equation coefficients. A first principle calculation of the Hall current is given. 3, 5, 7 electron tunneling and Josephson interference effects are predicted. (author)

  16. ε-iron nitrides: Intrinsic anomalous Hall ferromagnets

    Directory of Open Access Journals (Sweden)

    Guo-Ke Li

    2015-02-01

    Full Text Available The anomalous Hall effect in ε-iron nitrides (ε-Fe3-xN, 0 ≤ x ≤ 1 has been systematically investigated taking advantage of the fact that the exchange splitting of ε-Fe3-xN can be continuously tuned through the nitrogen concentration. It has been found that the anomalous Hall conductivity, σ x y A H , is proportional to the saturation magnetization MS, i.e., σ x y A H = S H M S , across significant variations in the saturation magnetization (96–1146 emu/cc. This relationship is in excellent agreement with the intrinsic mechanism as well as with the unified theory of AHE. Our results also demonstrate that the anomalous Hall conductivity is sensitive to the exchange splitting of the band structure.

  17. Signatures of lattice geometry in quantum and topological Hall effect

    International Nuclear Information System (INIS)

    Göbel, Börge; Mook, Alexander; Mertig, Ingrid; Henk, Jürgen

    2017-01-01

    The topological Hall effect (THE) of electrons in skyrmion crystals (SkXs) is strongly related to the quantum Hall effect (QHE) on lattices. This relation suggests to revisit the QHE because its Hall conductivity can be unconventionally quantized. It exhibits a jump and changes sign abruptly if the Fermi level crosses a van Hove singularity. In this Paper, we investigate the unconventional QHE features by discussing band structures, Hall conductivities, and topological edge states for square and triangular lattices; their origin are Chern numbers of bands in the SkX (THE) or of the corresponding Landau levels (QHE). Striking features in the energy dependence of the Hall conductivities are traced back to the band structure without magnetic field whose properties are dictated by the lattice geometry. Based on these findings, we derive an approximation that allows us to determine the energy dependence of the topological Hall conductivity on any two-dimensional lattice. The validity of this approximation is proven for the honeycomb lattice. We conclude that SkXs lend themselves for experiments to validate our findings for the THE and—indirectly—the QHE. (paper)

  18. Hall conductance and topological invariant for open systems.

    Science.gov (United States)

    Shen, H Z; Wang, W; Yi, X X

    2014-09-24

    The Hall conductivity given by the Kubo formula is a linear response of quantum transverse transport to a weak electric field. It has been intensively studied for quantum systems without decoherence, but it is barely explored for systems subject to decoherence. In this paper, we develop a formulism to deal with this issue for topological insulators. The Hall conductance of a topological insulator coupled to an environment is derived, the derivation is based on a linear response theory developed for open systems in this paper. As an application, the Hall conductance of a two-band topological insulator and a two-dimensional lattice is presented and discussed.

  19. Determination of intrinsic spin Hall angle in Pt

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yi; Deorani, Praveen; Qiu, Xuepeng; Kwon, Jae Hyun; Yang, Hyunsoo, E-mail: eleyang@nus.edu.sg [Department of Electrical and Computer Engineering, National University of Singapore, 117576 (Singapore)

    2014-10-13

    The spin Hall angle in Pt is evaluated in Pt/NiFe bilayers by spin torque ferromagnetic resonance measurements and is found to increase with increasing the NiFe thickness. To extract the intrinsic spin Hall angle in Pt by estimating the total spin current injected into NiFe from Pt, the NiFe thickness dependent measurements are performed and the spin diffusion in the NiFe layer is taken into account. The intrinsic spin Hall angle of Pt is determined to be 0.068 at room temperature and is found to be almost constant in the temperature range of 13–300 K.

  20. Determination of intrinsic spin Hall angle in Pt

    International Nuclear Information System (INIS)

    Wang, Yi; Deorani, Praveen; Qiu, Xuepeng; Kwon, Jae Hyun; Yang, Hyunsoo

    2014-01-01

    The spin Hall angle in Pt is evaluated in Pt/NiFe bilayers by spin torque ferromagnetic resonance measurements and is found to increase with increasing the NiFe thickness. To extract the intrinsic spin Hall angle in Pt by estimating the total spin current injected into NiFe from Pt, the NiFe thickness dependent measurements are performed and the spin diffusion in the NiFe layer is taken into account. The intrinsic spin Hall angle of Pt is determined to be 0.068 at room temperature and is found to be almost constant in the temperature range of 13–300 K.

  1. Fast surface waves in an ideal Hall-magnetohydrodynamic plasma slab

    International Nuclear Information System (INIS)

    Zhelyazkov, I.; Debosscher, A.; Goossens, M.

    1996-01-01

    The propagation of fast sausage and kink magnetohydrodynamic (MHD) surface waves in an ideal magnetized plasma slab is studied taking into account the Hall term in the generalized Ohm close-quote s law. It is found that the Hall effect modifies the dispersion characteristics of MHD surface modes when the Hall term scaling length is not negligible (less than, but comparable to the slab thickness). The dispersion relations for both modes have been derived for parallel propagation (along the ambient equilibrium magnetic field lines).The Hall term imposes some limits on the possible wave number range. It turns out that the space distribution of almost all perturbed quantities in sausage and kink surface waves with Hall effect is rather complicated as compared to that of usual fast MHD surface waves. The applicability to solar wind aspects of the results obtained, is briefly discussed. copyright 1996 American Institute of Physics

  2. Migrants and Their Experiences of Time: Edward T. Hall Revisited

    Directory of Open Access Journals (Sweden)

    Elisabeth Schilling

    2009-01-01

    Full Text Available In this paper we reassess the scientific heritage of Edward T. HALL and his contribution to the area of intercultural communication. The key objectives of our study are to demonstrate the applicability of HALL's theory of culture to empirical research and to establish its compatibility with other methods. Specifically, we propose that Alfred SCHÜTZ's phenomenology of sociality be taken as an extension to HALL. The connection between HALL and SCHÜTZ is made possible by the mutual emphases on the temporal dimension of culture and the temporal aspects of migration. With these foci we analyze six narratives by two groups of migrants: German and Russian. By combining HALL's theory of the cultural time with SCHÜTZ's phenomenological perspective on time and the Other and then applying them to empirical data, we show the terms in which different cultures experience time. URN: urn:nbn:de:0114-fqs0901357

  3. Critical current in the Integral Quantum Hall Effect

    International Nuclear Information System (INIS)

    Kostadinov, I.Z.

    1985-11-01

    A multiparticle theory of the Integral Quantum Hall Effect (IQHE) was constructed operating with pairs wave function as an order parameter. The IQHE is described with bosonic macroscopic states while the fractional QHE with fermionic ones. The calculation of the critical current and Hall conductivity temperature dependence is presented. (author)

  4. A Monolithic CMOS Magnetic Hall Sensor with High Sensitivity and Linearity Characteristics.

    Science.gov (United States)

    Huang, Haiyun; Wang, Dejun; Xu, Yue

    2015-10-27

    This paper presents a fully integrated linear Hall sensor by means of 0.8 μm high voltage complementary metal-oxide semiconductor (CMOS) technology. This monolithic Hall sensor chip features a highly sensitive horizontal switched Hall plate and an efficient signal conditioner using dynamic offset cancellation technique. An improved cross-like Hall plate achieves high magnetic sensitivity and low offset. A new spinning current modulator stabilizes the quiescent output voltage and improves the reliability of the signal conditioner. The tested results show that at the 5 V supply voltage, the maximum Hall output voltage of the monolithic Hall sensor microsystem, is up to ±2.1 V and the linearity of Hall output voltage is higher than 99% in the magnetic flux density range from ±5 mT to ±175 mT. The output equivalent residual offset is 0.48 mT and the static power consumption is 20 mW.

  5. A Monolithic CMOS Magnetic Hall Sensor with High Sensitivity and Linearity Characteristics

    Directory of Open Access Journals (Sweden)

    Haiyun Huang

    2015-10-01

    Full Text Available This paper presents a fully integrated linear Hall sensor by means of 0.8 μm high voltage complementary metal-oxide semiconductor (CMOS technology. This monolithic Hall sensor chip features a highly sensitive horizontal switched Hall plate and an efficient signal conditioner using dynamic offset cancellation technique. An improved cross-like Hall plate achieves high magnetic sensitivity and low offset. A new spinning current modulator stabilizes the quiescent output voltage and improves the reliability of the signal conditioner. The tested results show that at the 5 V supply voltage, the maximum Hall output voltage of the monolithic Hall sensor microsystem, is up to ±2.1 V and the linearity of Hall output voltage is higher than 99% in the magnetic flux density range from ±5 mT to ±175 mT. The output equivalent residual offset is 0.48 mT and the static power consumption is 20 mW.

  6. The ISOLDE hall

    CERN Multimedia

    Maximilien Brice

    2002-01-01

    Since 1992, after its move from the 600 MeV SC, ISOLDE is a customer of the Booster (then 1 GeV, now 1.4 GeV). The intense Booster beam (some 3E13 protons per pulse) is directed onto a target, from which a mixture of isotopes emanates. After ionization and electrostatic acceleration to 60 keV, they enter one of the 2 spectrometers (General Purpose Separator: GPS, and High Resolution Separator: HRS) from which the selected ions are directed to the experiments. The photos show: the REX-ISOLDE post accelerator; the mini-ball experiment; an overview of the ISOLDE hall. In the picture (_12) of the hall, the separators are behind the wall. From either of them, beams can be directed into any of the many beamlines towards the experiments, some of which are visible in the foreground. The elevated cubicle at the left is EBIS (Electron Beam Ion Source), which acts as a charge-state multiplier for the REX facility. The ions are further mass analzyzed and passed on to the linac which accelerates them to higher energies. T...

  7. Medical humanities: a resident doctor's perspective.

    Science.gov (United States)

    Pauranik, Anvita

    2012-01-01

    The barrage of competitive examinations, overwork, sleep deprivation, and the pressure of expectations all combine to destroy the dreams that resident doctors have when they start medical school. The empathy they had before entering this field fades away, and they eventually become insensitive to their patients. Medical humanities may be the means to halt this trend. Sensitising young minds, using the arts, literature, history and lessons on social issues, may bring about a paradigm shift in these doctors' outlook towards their patients. However, for the humanities to be integrated into medical education, the current curriculum must be modified and made more clinically and socially relevant. Further, the humanities cannot be taught in lecture halls; they need to be integrated into all aspects of medical school. For this, the medical school faculty should be sensitised to, and trained in, humanities education.

  8. Pregnancy and Parenthood among Surgery Residents: Results of the First Nationwide Survey of General Surgery Residency Program Directors.

    Science.gov (United States)

    Sandler, Britt J; Tackett, John J; Longo, Walter E; Yoo, Peter S

    2016-06-01

    Although family and lifestyle are known to be important factors for medical students choosing a specialty, there is a lack of research about general surgery residency program policies regarding pregnancy and parenthood. Similarly, little is known about program director attitudes about these issues. We performed a cross-sectional survey of United States (US) general surgery residency program directors. Sixty-six respondents completed the survey: 70% male, 59% from university-based programs, and 76% between 40 and 59 years of age. Two-thirds (67%) reported having a maternity leave policy. Less than half (48%) reported having a leave policy for the non-childbearing parent (paternity leave). Leave duration was most frequently reported as 6 weeks for maternity leave (58%) and 1 week for paternity leave (45%). Thirty-eight percent of general surgery residency program directors (PDs) reported availability of on-site childcare, 58% reported availability of lactation facilities. Forty-six percent of university PDs said that the research years are the best time to have a child during residency; 52% of independent PDs said that no particular time during residency is best. Sixty-one percent of PDs reported that becoming a parent negatively affects female trainees' work, including placing an increased burden on fellow residents (33%). Respondents perceived children as decreasing female trainees' well-being more often than male trainees' (32% vs 9%, p leave, length of leave, as well as inconsistency in access to childcare and availability of spaces to express and store breast milk. Program directors perceived parenthood to affect the training and well-being of female residents more adversely than that of male residents. Copyright © 2016 American College of Surgeons. All rights reserved.

  9. Prototype dining hall energy efficiency study

    Energy Technology Data Exchange (ETDEWEB)

    Mazzucchi, R.P.; Bailey, S.A.; Zimmerman, P.W.

    1988-06-01

    The energy consumption of food service facilities is among the highest of any commercial building type, owing to the special requirements for food preparation, sanitation, and ventilation. Consequently, the US Air Force Engineering and Services Center (AFESC) contracted with Pacific Northwest Laboratory (PNL) to collect and analyze end-use energy consumption data for a prototypical dining hall and make specific recommendations on cost-effective energy conservation options. This information will be used to establish or update criteria for dining hall designs and retrofits as appropriate. 6 refs., 21 figs., 23 tabs.

  10. Proton knock-out in Hall A

    International Nuclear Information System (INIS)

    Jager, K. de

    2003-01-01

    Proton knock-out is studied in a broad program in Hall A at Jefferson Lab. The first experiment performed in Hall A studied the 16 O(e,e'p) reaction. Since then proton knock-out experiments have studied a variety of aspects of that reaction, from single-nucleon properties to its mechanism, such as final-state interactions and two-body currents, in nuclei from 2 H to 16 O. In this review the accomplishments of this program will be summarized and an outlook given of expected future results. (orig.)

  11. Bound values for Hall conductivity of heterogeneous medium under ...

    Indian Academy of Sciences (India)

    - ditions in inhomogeneous medium has been studied. It is shown that bound values for. Hall conductivity differ from bound values for metallic conductivity. This is due to the unusual character of current percolation under quantum Hall effect ...

  12. G. Stanley Hall, Child Study, and the American Public.

    Science.gov (United States)

    Young, Jacy L

    2016-01-01

    In the final decades of the 19th century psychologist Granville Stanley Hall was among the most prominent pedagogical experts in the nation. The author explores Hall's carefully crafted persona as an educational expert, and his engagements with the American public, from 1880 to 1900, arguably the height of his influence. Drawing from accounts of Hall's lecture circuit in the popular press, a map of his talks across the nation is constructed to assess the geographic scope of his influence. These talks to educators on the psychology underlying childhood and pedagogy, and his views and research on child life more generally, were regularly discussed in newspapers and popular periodicals. The venues in which Hall's ideas were disseminated, discussed, and in some cases, dismissed are described. His efforts to mobilize popular support for, and assistance with, his research endeavors in child study are also discussed. Such efforts were controversial both within the burgeoning field of psychology and among the public. Through his various involvements in pedagogy, and concerted efforts to engage with the American public, Hall helped establish psychology's relevance to parenting and educational practices.

  13. Remediation plans in family medicine residency

    Science.gov (United States)

    Audétat, Marie-Claude; Voirol, Christian; Béland, Normand; Fernandez, Nicolas; Sanche, Gilbert

    2015-01-01

    Abstract Objective To assess use of the remediation instrument that has been implemented in training sites at the University of Montreal in Quebec to support faculty in diagnosing and remediating resident academic difficulties, to examine whether and how this particular remediation instrument improves the remediation process, and to determine its effects on the residents’ subsequent rotation assessments. Design A multimethods approach in which data were collected from different sources: remediation plans developed by faculty, program statistics for the corresponding academic years, and students’ academic records and rotation assessment results. Setting Family medicine residency program at the University of Montreal. Participants Family medicine residents in academic difficulty. Main outcome measures Assessment of the content, process, and quality of remediation plans, and students’ academic and rotation assessment results (successful, below expectations, or failure) both before and after the remediation period. Results The framework that was developed for assessing remediation plans was used to analyze 23 plans produced by 10 teaching sites for 21 residents. All plans documented cognitive problems and implemented numerous remediation measures. Although only 48% of the plans were of good quality, implementation of a remediation plan was positively associated with the resident’s success in rotations following the remediation period. Conclusion The use of remediation plans is well embedded in training sites at the University of Montreal. The residents’ difficulties were mainly cognitive in nature, but this generally related to deficits in clinical reasoning rather than knowledge gaps. The reflection and analysis required to produce a remediation plan helps to correct many academic difficulties and normalize the academic career of most residents in difficulty. Further effort is still needed to improve the quality of plans and to support teachers.

  14. Four-dimensional Hall mechanics as a particle on CP3

    International Nuclear Information System (INIS)

    Bellucci, Stefano; Casteill, Pierre-Yves; Nersessian, Armen

    2003-01-01

    In order to establish an explicit connection between four-dimensional Hall effect on S 4 and six-dimensional Hall effect on CP 3 , we perform the Hamiltonian reduction of a particle moving on CP 3 in a constant magnetic field to the four-dimensional Hall mechanics (i.e., a-bar particle on S 4 in a SU(2) instanton field). This reduction corresponds to fixing the isospin of the latter system

  15. Spin Hall Effect in Doped Semiconductor Structures

    Science.gov (United States)

    Tse, Wang-Kong; Das Sarma, Sankar

    2006-03-01

    We present a microscopic theory of the extrinsic spin Hall effect based on the diagrammatic perturbation theory. Side-jump (SJ) and skew-scattering (SS) contributions are explicitly taken into account to calculate the spin Hall conductivity, and we show their effects scale as σxy^SJ/σxy^SS ˜(/τ)/ɛF, where τ being the transport relaxation time. Motivated by recent experimental work we apply our theory to n-doped and p-doped 3D and 2D GaAs structures, obtaining analytical formulas for the SJ and SS contributions. Moreover, the ratio of the spin Hall conductivity to longitudinal conductivity is found as σs/σc˜10-3-10-4, in reasonable agreement with the recent experimental results of Kato et al. [Science 306, 1910 (2004)] in n-doped 3D GaAs system.

  16. What is the Hallé? | Smith | Philosophical Papers

    African Journals Online (AJOL)

    The bulk of the paper examines the difficulty of reconciling the view that the Hallé is several individuals with two prima facie plausible theses about the manner of its persistence through time. The paper is structured around some remarks made by Peter Simons about groups, and the Hallé in particular, in his Parts.

  17. Interaction Induced Quantum Valley Hall Effect in Graphene

    Directory of Open Access Journals (Sweden)

    E. C. Marino

    2015-03-01

    Full Text Available We use pseudo-quantum electrodynamics in order to describe the full electromagnetic interaction of the p electrons in graphene in a consistent 2D formulation. We first consider the effect of this interaction in the vacuum polarization tensor or, equivalently, in the current correlator. This allows us to obtain the T→0 conductivity after a smooth zero-frequency limit is taken in Kubo’s formula. Thereby, we obtain the usual expression for the minimal conductivity plus corrections due to the interaction that bring it closer to the experimental value. We then predict the onset of an interaction-driven spontaneous quantum valley Hall effect below an activation temperature of the order of 2 K. The transverse (Hall valley conductivity is evaluated exactly and shown to coincide with the one in the usual quantum Hall effect. Finally, by considering the effects of pseudo-quantum electrodynamics, we show that the electron self-energy is such that a set of P- and T-symmetric gapped electron energy eigenstates are dynamically generated, in association with the quantum valley Hall effect.

  18. Hall effects and related phenomena in disordered Rashba 2DEG

    International Nuclear Information System (INIS)

    Inoue, Jun-ichiro; Kato, Takashi; Bauer, Gerrit E W; Molenkamp, Laurens W

    2009-01-01

    We review our recent work on the spin and anomalous Hall effects and other related phenomena caused by the intrinsic spin–orbit interaction. We focus our attention on disorder effects on these transport properties by adopting a model of a two-dimensional electron gas with a Rashba-type spin–orbit interaction. A spin-polarized model is adopted to calculate the anomalous Hall effect and anisotropic magnetoresistance. It is shown that the spin Hall conductivity in the ballistic transport regime is cancelled by the so-called vertex corrections for the disorder scattering, and that the anomalous Hall conductivity and anisotropic magnetoresistance vanish unless the lifetime is spin dependent. We further present results on spin accumulation under an electric field

  19. Family medicine residents' practice intentions: Theory of planned behaviour evaluation.

    Science.gov (United States)

    Grierson, Lawrence E M; Fowler, Nancy; Kwan, Matthew Y W

    2015-11-01

    To assess residents' practice intentions since the introduction of the College of Family Physicians of Canada's Triple C curriculum, which focuses on graduating family physicians who will provide comprehensive care within traditional and newer models of family practice. A survey based on Ajzen's theory of planned behaviour was administered on 2 occasions. McMaster University in Hamilton, Ont. Residents (n = 135) who were enrolled in the Department of Family Medicine Postgraduate Residency Program at McMaster University in July 2012 and July 2013; 54 of the 60 first-year residents who completed the survey in 2012 completed it again in 2013. The survey was modeled so as to measure the respondents' intentions to practise with a comprehensive scope; determine the degree to which their attitudes, subjective norms, and perceptions of control about comprehensive practice influence those intentions; and investigate how these relationships change as residents progress through the curriculum. The survey also queried the respondents about their intentions with respect to particular medical services that underpin comprehensive practice. The responses indicate that the factors modeled by the theory of planned behaviour survey account for 60% of the variance in the residents' intentions to adopt a comprehensive scope of practice upon graduation, that there is room for curricular improvement with respect to encouraging residents to practise comprehensive care, and that targeting subjective norms about comprehensive practice might have the greatest influence on improving resident intentions. The theory of planned behaviour presents an effective approach to assessing curricular effects on resident practice intentions while also providing meaningful information for guiding further program evaluation efforts in the Department of Family Medicine at McMaster University.

  20. Theory of the quantum hall effects in lattice systems

    International Nuclear Information System (INIS)

    Kliros, G.S.

    1990-06-01

    The Fractional Quantum Hall Effect is identified as an Integral Quantum Hall Effect of electrons on a lattice with an even number of statistical flux quanta. A variational wavefunction in terms of the Hofstadter lattice eigenstates is proposed. (author). 21 refs

  1. The Isolde experimental hall

    CERN Multimedia

    Laurent Guiraud

    2000-01-01

    General view of the Isotope-Separator On-Line (ISOLDE) hall. ISOLDE is dedicated to the production of a large variety of radioactive ion beams for many different experiments. Rare isotopes can be produced allowing the study of spectra for neutrino beam production.

  2. Bulk Versus Edge in the Quantum Hall Effect

    OpenAIRE

    Kao, Y. -C.; Lee, D. -H.

    1996-01-01

    The manifestation of the bulk quantum Hall effect on edge is the chiral anomaly. The chiral anomaly {\\it is} the underlying principle of the ``edge approach'' of quantum Hall effect. In that approach, $\\sxy$ should not be taken as the conductance derived from the space-local current-current correlation function of the pure one-dimensional edge problem.

  3. An evaluation of krypton propellant in Hall thrusters

    Science.gov (United States)

    Linnell, Jesse Allen

    Due to its high specific impulse and low price, krypton has long sparked interest as an alternate Hall thruster propellant. Unfortunately at the moment, krypton's relatively poor performance precludes it as a legitimate option. This thesis presents a detailed investigation into krypton operation in Hall thrusters. These findings suggest that the performance gap can be decreased to 4% and krypton can finally become a realistic propellant option. Although krypton has demonstrated superior specific impulse, the xenon-krypton absolute efficiency gap ranges between 2 and 15%. A phenomenological performance model indicates that the main contributors to the efficiency gap are propellant utilization and beam divergence. Propellant utilization and beam divergence have relative efficiency deficits of 5 and 8%, respectively. A detailed characterization of internal phenomena is conducted to better understand the xenon-krypton efficiency gap. Krypton's large beam divergence is found to be related to a defocusing equipotential structure and a weaker magnetic field topology. Ionization processes are shown to be linked to the Hall current, the magnetic mirror topology, and the perpendicular gradient of the magnetic field. Several thruster design and operational suggestions are made to optimize krypton efficiency. Krypton performance is optimized for discharge voltages above 500 V and flow rates corresponding to an a greater than 0.015 mg/(mm-s), where alpha is a function of flow rate and discharge channel dimensions (alpha = m˙alphab/Ach). Performance can be further improved by increasing channel length or decreasing channel width for a given flow rate. Also, several magnetic field design suggestions are made to enhance ionization and beam focusing. Several findings are presented that improve the understanding of general Hall thruster physics. Excellent agreement is shown between equipotential lines and magnetic field lines. The trim coil is shown to enhance beam focusing

  4. Meeting American Geriatrics Society Competencies: Are Residents Meeting Expectations for Quality Care of Older Adults?

    Science.gov (United States)

    Bynum, Debra L; Wilson, Lindsay A; Ong, Thuan; Callahan, Kathryn E; Dalton, Thomas; Ohuabunwa, Ugochi

    2015-09-01

    In order to determine how often internal medicine and family medicine residents performed specific actions related to the geriatric competencies established by the American Geriatrics Society (AGS) when caring for older hospitalized adults, a cross-sectional anonymous survey of residents at the University of North Carolina, University of Washington, Wake Forest University, Duke University, and Emory University was undertaken. Data on frequency of self-reported behaviors were analyzed, with comparisons made for different levels of training, institution, and program. A total of 375 residents responded for an overall response rate of 48%. Residents reported that they often do not demonstrate all of the AGS recommended core competencies when caring for older adults in the hospital setting. Residents report more frequently performing activities that are routinely integrated into hospital systems such as reviewing medication lists, working with an interdisciplinary team, evaluating for inappropriate bladder catheters, and evaluating for pressure ulcers. There were no consistent differences between institutions and only minor differences noted between Family Medicine and Internal Medicine residents. Operationalizing core competencies by integrating them into hospital systems' quality process indicators may prompt more consistent high-quality care and ensure systems support residents' competence. © 2015, Copyright the Authors Journal compilation © 2015, The American Geriatrics Society.

  5. Magnetic field deformation due to electron drift in a Hall thruster

    Directory of Open Access Journals (Sweden)

    Han Liang

    2017-01-01

    Full Text Available The strength and shape of the magnetic field are the core factors in the design of the Hall thruster. However, Hall current can affect the distribution of static magnetic field. In this paper, the Particle-In-Cell (PIC method is used to obtain the distribution of Hall current in the discharge channel. The Hall current is separated into a direct and an alternating part to calculate the induced magnetic field using Finite Element Method Magnetics (FEMM. The results show that the direct Hall current decreases the magnetic field strength in the acceleration region and also changes the shape of the magnetic field. The maximum reduction in radial magnetic field strength in the exit plane is 10.8 G for an anode flow rate of 15 mg/s and the maximum angle change of the magnetic field line is close to 3° in the acceleration region. The alternating Hall current induces an oscillating magnetic field in the whole discharge channel. The actual magnetic deformation is shown to contain these two parts.

  6. Evaluation of Professional Role Competency during Psychiatry Residency

    Science.gov (United States)

    Grujich, Nikola N.; Razmy, Ajmal; Zaretsky, Ari; Styra, Rima G.; Sockalingam, Sanjeev

    2012-01-01

    Objective: The authors sought to determine psychiatry residents' perceptions on the current method of evaluating professional role competency and the use of multi-source feedback (MSF) as an assessment tool. Method: Authors disseminated a structured, anonymous survey to 128 University of Toronto psychiatry residents, evaluating the current mode of…

  7. The impact of transitioning from a 24-hour to a 16-hour call model amongst a cohort of Canadian anesthesia residents at McMaster University – a survey study

    Directory of Open Access Journals (Sweden)

    Sussman D

    2015-08-01

    Full Text Available David Sussman, James E Paul Department of Anesthesia, McMaster University, Hamilton, ON, Canada Purpose: The primary objective of this study was to assess anesthesia residents' opinions and perceptions on wellness/burnout, fatigue, education, and patient safety after the initiation of a reduced call model (16-hour call. Methods: A prospective cohort study was conducted at three time points during the 2013–2014 academic year. A web-based questionnaire consisting of 23 questions was electronically distributed to all anesthesia residents from postgraduate years (PGY 1 to 5 who were part of the active call roster (n=84 at McMaster University in Hamilton, Ontario. Descriptive summaries were calculated, counts and percentages were used for categorical variables, and answers to open text questions were reviewed for themes. Results: A response rate of 67% was obtained for this study. A majority of anesthesia residents (65% approved of 16-hour call, felt that their overall quality of life as a senior resident (PGY3 or greater or junior resident (PGY2 and below had improved (73% and 55%, respectively, and reported overall feeling less fatigued. Most respondents indicated that the quality of education remained unchanged (47%, or had improved (31%. And most felt better prepared for the royal college exam (52%. Most felt patient safety had improved or was unchanged (both 48%. Conclusion: The study demonstrates that 16-hour call improved resident wellness, reduced burnout and fostered an environment where residents are less fatigued and more satisfied with their educational experience promoting an environment of patient safety. Overall, the anesthesia residency group demonstrated that not only is 16-hour call preferred but beneficial. Keywords: resident wellness, reduced call model, duty hours, patient safety, cohort study, fatigue 

  8. Current Percolation in Medium with Boundaries under Quantum Hall Effect Conditions

    Directory of Open Access Journals (Sweden)

    M. U. Malakeeva

    2012-01-01

    Full Text Available The current percolation has been considered in the medium with boundaries under quantum Hall effect conditions. It has been shown that in that case the effective Hall conductivity has a nonzero value due to percolation of the Hall current through the finite number of singular points (in our model these are corners at the phase joints.

  9. Developments in Scanning Hall Probe Microscopy

    Science.gov (United States)

    Chouinard, Taras; Chu, Ricky; David, Nigel; Broun, David

    2009-05-01

    Low temperature scanning Hall probe microscopy is a sensitive means of imaging magnetic structures with high spatial resolution and magnetic flux sensitivity approaching that of a Superconducting Quantum Interference Device. We have developed a scanning Hall probe microscope with novel features, including highly reliable coarse positioning, in situ optimization of sensor-sample alignment and capacitive transducers for linear, long range positioning measurement. This has been motivated by the need to reposition accurately above fabricated nanostructures such as small superconducting rings. Details of the design and performance will be presented as well as recent progress towards time-resolved measurements with sub nanosecond resolution.

  10. Fractional statistics and fractional quantized Hall effect

    International Nuclear Information System (INIS)

    Tao, R.; Wu, Y.S.

    1985-01-01

    The authors suggest that the origin of the odd-denominator rule observed in the fractional quantized Hall effect (FQHE) may lie in fractional statistics which govern quasiparticles in FQHE. A theorem concerning statistics of clusters of quasiparticles implies that fractional statistics do not allow coexistence of a large number of quasiparticles at fillings with an even denominator. Thus, no Hall plateau can be formed at these fillings, regardless of the presence of an energy gap. 15 references

  11. High-performance LED luminaire for sports hall

    Science.gov (United States)

    Lee, Xuan-Hao; Yang, Jin-Tsung; Chien, Wei-Ting; Chang, Jung-Hsuan; Lo, Yi-Chien; Lin, Che-Chu; Sun, Ching-Cherng

    2015-09-01

    In this paper, we present a luminaire design with anti-glare and energy-saving effects for sports hall. Compared with traditional lamps using in a badminton court, the average illuminance on the ground of the proposed LED luminaire is enhanced about 300%. Besides, the uniformity is obviously enhanced and improved. The switch-on speed of lighting in sports hall is greatly reduced from 5-10 minutes to 1 second. The simulation analysis and the corresponding experiment results are demonstrated.

  12. General vibration monitoring: Experimental hall

    International Nuclear Information System (INIS)

    Jendrzejczyk, J.A.; Wambsganss, M.W.; Smith, R.K.

    1993-01-01

    The reported vibration data were generated from measurements made on the experimental hall floor on December 2, 1992. At the time of the measurements, the ESRF hydrolevel was set-up in the Early Assembly Area (EAA) of the experimental hall and was being used to measure static displacement (settlement) of the floor. The vibration measurement area was on and adjacent to the EAA, in the vicinity of the ESRF hydrolevel test which was in progress. This report summarizes the objectives, instrumentation, measurement locations, observations, and conclusions, and provides selected results in the form of RMS vs. time plots, and power spectral densities from which frequency information can be derived. Measured response amplitudes were within the vibration criteria established for the APS

  13. All Optical Measurement Proposed for the Photovoltaic Hall Effect

    International Nuclear Information System (INIS)

    Oka, Takashi; Aoki, Hideo

    2011-01-01

    We propose an all optical way to measure the recently proposed p hotovoltaic Hall effect , i.e., a Hall effect induced by a circularly polarized light in the absence of static magnetic fields. This is done in a pump-probe experiment with the Faraday rotation angle being the probe. The Floquet extended Kubo formula for photo-induced optical response is formulated and the ac-Hall conductivity is calculated. We also point out the possibility of observing the effect in two layered graphene, three-dimensional graphite, and more generally in multi-band systems such as materials described by the dp-model.

  14. Useful Pedagogical Applications of the Classical Hall Effect

    Science.gov (United States)

    Houari, Ahmed

    2007-01-01

    One of the most known phenomena in physics is the Hall effect. This is mainly due to its simplicity and to the wide range of its theoretical and practical applications. To complete the pedagogical utility of the Hall effect in physics teaching, I will apply it here to determine the Faraday constant as a fundamental physical number and the number…

  15. Single particle detection: Phase control in submicron Hall sensors

    International Nuclear Information System (INIS)

    Di Michele, Lorenzo; Shelly, Connor; Gallop, John; Kazakova, Olga

    2010-01-01

    We present a phase-sensitive ac-dc Hall magnetometry method which allows a clear and reliable separation of real and parasitic magnetic signals of a very small magnitude. High-sensitivity semiconductor-based Hall crosses are generally accepted as a preferential solution for non-invasive detection of superparamagnetic nanobeads used in molecular biology, nanomedicine, and nanochemistry. However, detection of such small beads is often hindered by inductive pick-up and other spurious signals. The present work demonstrates an unambiguous experimental route for detection of small magnetic moments and provides a simple theoretical background for it. The reliability of the method has been tested for a variety of InSb Hall sensors in the range 600 nm-5 μm. Complete characterization of empty devices, involving Hall coefficients and noise measurements, has been performed and detection of a single FePt bead with diameter of 140 nm and magnetic moment of μ≅10 8 μ B has been achieved with a 600 nm-wide sensor.

  16. Perceptions, training experiences, and preferences of surgical residents toward laparoscopic simulation training: a resident survey.

    Science.gov (United States)

    Shetty, Shohan; Zevin, Boris; Grantcharov, Teodor P; Roberts, Kurt E; Duffy, Andrew J

    2014-01-01

    Simulation training for surgical residents can shorten learning curves, improve technical skills, and expedite competency. Several studies have shown that skills learned in the simulated environment are transferable to the operating room. Residency programs are trying to incorporate simulation into the resident training curriculum to supplement the hands-on experience gained in the operating room. Despite the availability and proven utility of surgical simulators and simulation laboratories, they are still widely underutilized by surgical trainees. Studies have shown that voluntary use leads to minimal participation in a training curriculum. Although there are several simulation tools, there is no clear evidence of the superiority of one tool over the other in skill acquisition. The purpose of this study was to explore resident perceptions, training experiences, and preferences regarding laparoscopic simulation training. Our goal was to profile resident participation in surgical skills simulation, recognize potential barriers to voluntary simulator use, and identify simulation tools and tasks preferred by residents. Furthermore, this study may help to inform whether mandatory/protected training time, as part of the residents' curriculum is essential to enhance participation in the simulation laboratory. A cross-sectional study on general surgery residents (postgraduate years 1-5) at Yale University School of Medicine and the University of Toronto via an online questionnaire was conducted. Overall, 67 residents completed the survey. The institutional review board approved the methods of the study. Overall, 95.5% of the participants believed that simulation training improved their laparoscopic skills. Most respondents (92.5%) perceived that skills learned during simulation training were transferrable to the operating room. Overall, 56.7% of participants agreed that proficiency in a simulation curriculum should be mandatory before operating room experience. The

  17. DISK FORMATION IN MAGNETIZED CLOUDS ENABLED BY THE HALL EFFECT

    International Nuclear Information System (INIS)

    Krasnopolsky, Ruben; Shang, Hsien; Li Zhiyun

    2011-01-01

    Stars form in dense cores of molecular clouds that are observed to be significantly magnetized. A dynamically important magnetic field presents a significant obstacle to the formation of protostellar disks. Recent studies have shown that magnetic braking is strong enough to suppress the formation of rotationally supported disks in the ideal MHD limit. Whether non-ideal MHD effects can enable disk formation remains unsettled. We carry out a first study on how disk formation in magnetic clouds is modified by the Hall effect, the least explored of the three non-ideal MHD effects in star formation (the other two being ambipolar diffusion and Ohmic dissipation). For illustrative purposes, we consider a simplified problem of a non-self-gravitating, magnetized envelope collapsing onto a central protostar of fixed mass. We find that the Hall effect can spin up the inner part of the collapsing flow to Keplerian speed, producing a rotationally supported disk. The disk is generated through a Hall-induced magnetic torque. Disk formation occurs even when the envelope is initially non-rotating, provided that the Hall coefficient is large enough. When the magnetic field orientation is flipped, the direction of disk rotation is reversed as well. The implication is that the Hall effect can in principle produce both regularly rotating and counter-rotating disks around protostars. The Hall coefficient expected in dense cores is about one order of magnitude smaller than that needed for efficient spin-up in these models. We conclude that the Hall effect is an important factor to consider in studying the angular momentum evolution of magnetized star formation in general and disk formation in particular.

  18. NASA HERMeS Hall Thruster Electrical Configuration Characterization

    Science.gov (United States)

    Peterson, Peter; Kamhawi, Hani; Huang, Wensheng; Yim, John; Herman, Daniel; Williams, George; Gilland, James; Hofer, Richard

    2016-01-01

    NASAs Hall Effect Rocket with Magnetic Shielding (HERMeS) 12.5 kW Technology Demonstration Unit-1 (TDU-1) Hall thruster has been the subject of extensive technology maturation in preparation for development into a flight ready propulsion system. Part of the technology maturation was to test the TDU-1 thruster in several ground based electrical configurations to assess the thruster robustness and suitability to successful in-space operation. The ground based electrical configuration testing has recently been demonstrated as an important step in understanding and assessing how a Hall thruster may operate differently in space compared to ground based testing, and to determine the best configuration to conduct development and qualification testing. This presentation will cover the electrical configuration testing of the TDU-1 HERMeS Hall thruster in NASA Glenn Research Centers Vacuum Facility 5. The three electrical configurations examined are the thruster body tied to facility ground, thruster floating, and finally the thruster body electrically tied to cathode common. The TDU-1 HERMeS was configured with two different exit plane boundary conditions, dielectric and conducting, to examine the influence on the electrical configuration characterization.

  19. Inverse spin Hall effect by spin injection

    Science.gov (United States)

    Liu, S. Y.; Horing, Norman J. M.; Lei, X. L.

    2007-09-01

    Motivated by a recent experiment [S. O. Valenzuela and M. Tinkham, Nature (London) 442, 176 (2006)], the authors present a quantitative microscopic theory to investigate the inverse spin-Hall effect with spin injection into aluminum considering both intrinsic and extrinsic spin-orbit couplings using the orthogonalized-plane-wave method. Their theoretical results are in good agreement with the experimental data. It is also clear that the magnitude of the anomalous Hall resistivity is mainly due to contributions from extrinsic skew scattering.

  20. Are tent halls subject to property tax?

    Directory of Open Access Journals (Sweden)

    Mariusz Macudziński

    2016-12-01

    Full Text Available The presented publication is a response to currently asked questions and interpretative doubts of taxpayers and tax authorities, namely whether tent halls are subject to property tax. General issues connected with an entity and a subject of taxation of this tax are presented herein. The answer to the question asked is then provided through the qualification of constructions works and the allocation of tent halls in the proper category of the works, with the use of the current law.

  1. Resistive Instabilities in Hall Current Plasma Discharge

    International Nuclear Information System (INIS)

    Litvak, Andrei A.; Fisch, Nathaniel J.

    2000-01-01

    Plasma perturbations in the acceleration channel of a Hall thruster are found to be unstable in the presence of collisions. Both electrostatic lower-hybrid waves and electromagnetic Alfven waves transverse to the applied electric and magnetic field are found to be unstable due to collisions in the E X B electron flow. These results are obtained assuming a two-fluid hydrodynamic model in slab geometry. The characteristic frequencies of these modes are consistent with experimental observations in Hall current plasma thrusters

  2. Hall Conductivity in a Quasi-Two-Dimensional Disordered Electron System

    Institute of Scientific and Technical Information of China (English)

    YANG Yong-Hong; WANG Yong-Gang; LIU Mei

    2002-01-01

    By making use of the diagrammatic techniques in perturbation theory,we have investigated the Hall effect in a quasi-two-dimensional disordered electron system.In the weakly localized regime,the analytical expression for quantum correction to Hall conductivity has been obtained using the Kubo formalism and quasiclassical approximation.The relevant dimensional crossover behavior from three dimensions to two dimensions with decreasing the interlayer hopping energy is discussed.The quantum interference effect is shown to have a vanishing correction t,o the Hall coefficient.

  3. The Relationship Between Academic Motivation and Lifelong Learning During Residency: A Study of Psychiatry Residents.

    Science.gov (United States)

    Sockalingam, Sanjeev; Wiljer, David; Yufe, Shira; Knox, Matthew K; Fefergrad, Mark; Silver, Ivan; Harris, Ilene; Tekian, Ara

    2016-10-01

    To examine the relationship between lifelong learning (LLL) and academic motivation for residents in a psychiatry residency program, trainee factors that influence LLL, and psychiatry residents' LLL practices. Between December 2014 and February 2015, 105 of 173 (61%) eligible psychiatry residents from the Department of Psychiatry, University of Toronto, completed a questionnaire with three study instruments: an LLL needs assessment survey, the Jefferson Scale of Physician Lifelong Learning (JeffSPLL), and the Academic Motivation Scale (AMS). The AMS included a relative autonomy motivation score (AMS-RAM) measuring the overall level of intrinsic motivation (IM). A significant correlation was observed between JeffSPLL and AMS-RAM scores (r = 0.39, P motivation identification domain (mean difference [M] = 0.38; 95% confidence interval [CI] [0.01, 0.75]; P = .045; d = 0.44) compared with senior residents. Clinician scientist stream (CSS) residents had significantly higher JeffSPLL scores compared with non-CSS residents (M = 3.15; 95% CI [0.52, 5.78]; P = .020; d = 0.57). The use of rigorous measures to study LLL and academic motivation confirmed prior research documenting the positive association between IM and LLL. The results suggest that postgraduate curricula aimed at enhancing IM, for example, through support for learning autonomously, could be beneficial to cultivating LLL in learners.

  4. A Study on Evaluation of Living Environment by Students' Preferences in Residences

    OpenAIRE

    鶴崎, 直樹; 坂井, 猛; 上野, 武; 有馬, 隆文; Tsurusaki, Naoki; Sakai, Takeru; Ueno, Takeshi; Arima, Takafumi

    2006-01-01

    The purpose of this paper was to construct a living quarters environment evaluation method by surveying students' preferences in residences and to apply the evaluation method to the Kyushu University Hakozaki campus so as to inspect the method's efficacy and applicability to a new campus. The obtained results included: 1)information about preferences in residence selection by students attending Kyushu University. 2)proof of efficacy from the viewpoint of students in the Kyushu University Hako...

  5. Algorithm and exploratory study of the Hall MHD Rayleigh-Taylor instability

    International Nuclear Information System (INIS)

    Gardiner, Thomas Anthony

    2010-01-01

    This report is concerned with the influence of the Hall term on the nonlinear evolution of the Rayleigh-Taylor (RT) instability. This begins with a review of the magnetohydrodynamic (MHD) equations including the Hall term and the wave modes which are present in the system on time scales short enough that the plasma can be approximated as being stationary. In this limit one obtains what are known as the electron MHD (EMHD) equations which support two characteristic wave modes known as the whistler and Hall drift modes. Each of these modes is considered in some detail in order to draw attention to their key features. This analysis also serves to provide a background for testing the numerical algorithms used in this work. The numerical methods are briefly described and the EMHD solver is then tested for the evolution of whistler and Hall drift modes. These methods are then applied to study the nonlinear evolution of the MHD RT instability with and without the Hall term for two different configurations. The influence of the Hall term on the mixing and bubble growth rate are analyzed.

  6. An Investigation of Psychiatry Residents' Important Experiences

    Science.gov (United States)

    Long, Jody

    2011-01-01

    This research study was conducted to explore the phenomenon of the third-year experiences of the psychiatry residents. A review of the literature identified themes and subthemes related to the third-year of psychiatry education. The study was conducted at a university health science center. Data were collected from five residents using participant…

  7. Global Linear Stability Analysis of the Spoke Oscillation in Hall Effect Thrusters

    Science.gov (United States)

    2014-07-15

    meνeχ 2 nTe qex (4.1f) ddc dx = 2cpl vix ≡ γ (4.1g) where x is the axial coordinate along the thruster channel; e, me and mi are the electron charge...mi ) P − ( 5 2 Te mi nvex + qex mi ) 1 dc ddc dξ (4.25i) ddc dξ = Pγ (4.25j) Distribution A: Approved for public release; distribution is unlimited...Thruster. PhD thesis, Standford University , 2011. [128] D. Liu, R.E. Huffman, R.D. Branam, and W.A. Hargus. Ultrahigh-speed imaging of hall-thruster

  8. Hall probe magnetometer for SSC magnet cables

    International Nuclear Information System (INIS)

    Cross, R.W.; Goldfarb, R.B.

    1991-01-01

    The authors of this paper constructed a Hall probe magnetometer to measure the magnetization hysteresis loops of Superconducting Super Collider magnet cables. The instrument uses two Hall-effect field sensors to measure the applied field H and the magnetic induction B. Magnetization M is calculated from the difference of the two quantities. The Hall probes are centered coaxially in the bore of a superconducting solenoid with the B probe against the sample's broad surface. An alternative probe arrangement, in which M is measured directly, aligns the sample probe parallel to the field. The authors measured M as a function of H and field cycle rate both with and without a dc transport current. Flux creep as a function of current was measured from the dependence of ac loss on the cycling rate and from the decay of magnetization with time. Transport currents up to 20% of the critical current have minimal effect on magnetization and flux creep

  9. [Resident evaluation of general surgery training programs].

    Science.gov (United States)

    Espinoza G, Ricardo; Danilla E, Stefan; Valdés G, Fabio; San Francisco R, Ignacio; Llanos L, Osvaldo

    2009-07-01

    The profile of the general surgeon has changed, aiming to incorporate new skills and to develop new specialties. To assess the quality of postgraduate General Surgery training programs given by Chilean universities, the satisfaction of students and their preferences after finishing the training period. A survey with multiple choice and Likert type questions was designed and applied to 77 surgery residents, corresponding to 59% of all residents of general surgery specialization programs of Chilean universities. Fifty five per cent of residents financed with their own resources the specialization program. Thirty nine percent disagreed partially or totally with the objectives and rotations of programs. The opportunity to perform surgical interventions and the support by teachers was well evaluated. However, 23% revealed teacher maltreatment. Fifty six percent performed research activities, 73% expected to continue training in a derived specialty and 69% was satisfied with the training program. Residents considered that the quality and dedication of professors and financing of programs are issues that must be improved. The opportunity to perform surgical interventions, obtaining a salary for their work and teacher support is considered of utmost importance.

  10. Factors associated with burnout syndrome in medical residents of a university hospital.

    Science.gov (United States)

    Gouveia, Pedro Alves da Cruz; Ribeiro, Maria Hosana Chaves; Aschoff, Carlos Alberto de Moura; Gomes, Doris Pires; Silva, Nadine Anita Fonseca da; Cavalcanti, Helton Alexsandro Firmino

    2017-06-01

    To determine the prevalence of burnout syndrome among resident physicians of various specialties and to evaluate associated factors. The Maslach Burnout Inventory questionnaire and a sociodemographic questionnaire were used to evaluate factors associated with the syndrome. Burnout was defined as the association of high emotional exhaustion, depersonalization and low professional achievement. Multivariate analysis was performed after adjustment of the Poisson model with the identification of risk factors and calculation of prevalence ratios (PR). Of the 250 resident physicians registered with Hospital das Clínicas of Pernambuco, 129 participated in the study. In the three domains that characterize burnout syndrome, we found a low level of professional achievement in 94.6% of resident physicians interviewed, a high level of depersonalization in 31.8%, and 59.7% with a high level of emotional exhaustion. The prevalence of burnout was 27.9%. Having suffered a stressful event in the last six months (PR: 8.10; 95CI 1.2-57.2) and being a student of surgical specialty (PR: 1.99; 95CI 1.2-3.3) were independently associated with burnout. The prevalence of burnout found in resident physicians is in accordance with previous Brazilian studies. Residents of surgical specialties and those who suffered some stressful event were identified as susceptible in this study. The early identification of risk factors is fundamental for the implementation of preventive measures against burnout syndrome.

  11. Quantum Hall resistance standard in graphene devices under relaxed experimental conditions

    Science.gov (United States)

    Schopfer, F.; Ribeiro-Palau, R.; Lafont, F.; Brun-Picard, J.; Kazazis, D.; Michon, A.; Cheynis, F.; Couturaud, O.; Consejo, C.; Jouault, B.; Poirier, W.

    Large-area and high-quality graphene devices synthesized by CVD on SiC are used to develop reliable electrical resistance standards, based on the quantum Hall effect (QHE), with state-of-the-art accuracy of 1x10-9 and under an extended range of experimental conditions of magnetic field (down to 3.5 T), temperature (up to 10 K) or current (up to 0.5 mA). These conditions are much relaxed as compared to what is required by GaAs/AlGaAs standards and will enable to broaden the use of the primary quantum electrical standards to the benefit of Science and Industry for electrical measurements. Furthermore, by comparison of these graphene devices with GaAs/AlGaAs standards, we demonstrate the universality of the QHE within an ultimate uncertainty of 8.2x10-11. This suggests the exact relation of the quantized Hall resistance with the Planck constant and the electron charge, which is crucial for the new SI to be based on fixing such fundamental constants. These results show that graphene realizes its promises and demonstrates its superiority over other materials for a demanding application. Nature Nanotech. 10, 965-971, 2015, Nature Commun. 6, 6806, 2015

  12. The quantum Hall effect in quantum dot systems

    International Nuclear Information System (INIS)

    Beltukov, Y M; Greshnov, A A

    2014-01-01

    It is proposed to use quantum dots in order to increase the temperatures suitable for observation of the integer quantum Hall effect. A simple estimation using Fock-Darwin spectrum of a quantum dot shows that good part of carriers localized in quantum dots generate the intervals of plateaus robust against elevated temperatures. Numerical calculations employing local trigonometric basis and highly efficient kernel polynomial method adopted for computing the Hall conductivity reveal that quantum dots may enhance peak temperature for the effect by an order of magnitude, possibly above 77 K. Requirements to potentials, quality and arrangement of the quantum dots essential for practical realization of such enhancement are indicated. Comparison of our theoretical results with the quantum Hall measurements in InAs quantum dot systems from two experimental groups is also given

  13. The electronic residency application service application can predict accreditation council for graduate medical education competency-based surgical resident performance.

    Science.gov (United States)

    Tolan, Amy M; Kaji, Amy H; Quach, Chi; Hines, O Joe; de Virgilio, Christian

    2010-01-01

    Program directors often struggle to determine which factors in the Electronic Residency Application Service (ERAS) application are important in the residency selection process. With the establishment of the Accreditation Council for Graduate Medical Education (ACGME) competencies, it would be important to know whether information available in the ERAS application can predict subsequent competency-based performance of general surgery residents. This study is a retrospective correlation of data points found in the ERAS application with core competency-based clinical rotation evaluations. ACGME competency-based evaluations as well as technical skills assessment from all rotations during residency were collected. The overall competency score was defined as an average of all 6 competencies and technical skills. A total of77 residents from two (one university and one community based university-affiliate) general surgery residency programs were included in the analysis. Receiving honors for many of the third year clerkships and AOA membership were associated with a number of the individual competencies. USMLE scores were predictive only of Medical Knowledge (p = 0.004). Factors associated with higher overall competency were female gender (p = 0.02), AOA (p = 0.06), overall number of honors received (p = 0.04), and honors in Ob/Gyn (p = 0.03) and Pediatrics (p = 0.05). Multivariable analysis showed honors in Ob/Gyn, female gender, older age, and total number of honors to be predictive of a number of individual core competencies. USMLE scores were only predictive of Medical Knowledge. The ERAS application is useful for predicting subsequent competency based performance in surgical residents. Receiving honors in the surgery clerkship, which has traditionally carried weight when evaluating a potential surgery resident, may not be as strong a predictor of future success. Copyright © 2010 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights

  14. Quantum Hall conductivity in a Landau type model with a realistic geometry

    International Nuclear Information System (INIS)

    Chandelier, F.; Georgelin, Y.; Masson, T.; Wallet, J.-C.

    2003-01-01

    In this paper, we revisit some quantum mechanical aspects related to the quantum Hall effect. We consider a Landau type model, paying a special attention to the experimental and geometrical features of quantum Hall experiments. The resulting formalism is then used to compute explicitly the Hall conductivity from a Kubo formula

  15. "Hall mees" Linnateatris / Triin Sinissaar

    Index Scriptorium Estoniae

    Sinissaar, Triin

    1999-01-01

    Tallinn Linnateatri ja Raadioteatri ühislavastus "Hall mees" Gill Adamsi näidendi järgi, lavastaja Eero Spriit, osades Helene Vannari ja Väino Laes, kunstnik Kustav - Agu Püüman. Esietendus 22. okt

  16. Problems of radiation protection and their solution in afterloading therapy performed in a X-ray deep therapy chamber of the Radiological Clinic of the Martin-Luther-University Halle

    International Nuclear Information System (INIS)

    Rauh, G.

    1982-01-01

    The Radiological Clinic of the Martin-Luther-University Halle got the first afterloading therapy unit DECATRON in December 1973. After preceding physical measurements the first patient was irradiated in August 1974. At this time there was no experience with the afterloading therapy in the GDR. The afterloading therapy was performed in a former X-ray deep therapy chamber. The occuring problems of radiation protection are considered and the ways of solution are described. Radiation protection calculations were carried out, values of local dose measurements are given, interpreted and compared with the values of personal dosimetry. Also the terms 'incorporated activity' and 'threading out activity' ('effective activity') are discussed, which led to differences in dose measurements formerly. The special situation required to discuss radiation protection problems of X-ray deep therapy simultaneously. (author)

  17. Radiation conditions in the ring hall of the IHEP proton synchrotron

    International Nuclear Information System (INIS)

    Borodin, V.E.; Ermolenko, L.S.; Obryashchikova, L.P.

    1975-01-01

    The paper presents the results on studying the radiation conditions caused by induced radioactivity of the accelerator units in the ring hall. The data on the induced radioactivity level just on the ring vacuum chamber are reported. Radiation conditions in the most characteristic areas of the hall are considered. The changes in time of the dose rate at the internal target and at the entrance to the hall are shown

  18. The Monty Hall Dilemma.

    Science.gov (United States)

    Granberg, Donald; Brown, Thad A.

    1995-01-01

    Examines people's behavior in the Monty Hall Dilemma (MHD), in which a person must make two decisions to win a prize. In a series of five studies, found that people misapprehend probabilities in the MHD. Discusses the MHD's relation to illusion of control, belief perseverance, and the status quo bias. (RJM)

  19. Suitable reverberation time for halls for rock and pop music

    DEFF Research Database (Denmark)

    Adelman-Larsen, Niels Werner; Thompson, Eric Robert; Gade, Anders Christian

    2010-01-01

    The existing body of literature regarding the acoustic design of concert halls has focused almost exclusively on classical music, although there are many more performances of popular music, including rock and pop. Objective measurements were made of the acoustics of 20 rock music venues in Denmark....... The best-rated halls in the study have reverberation times that are approximately frequency independent from 0.6 to 1.2 s for hall volumes from 1000 to 6000 m3. The worst rated halls in the study had significantly higher reverberation times in the 63 and 125 Hz bands. Since most audiences at rock concerts...... are standing, absorption coefficients were measured with a standing audience from 63 Hz to 4 kHz. These measurements showed that a standing audience absorbs about five times as much energy in mid-/high-frequency bands as in low-frequency bands....

  20. Low-Cost, High-Performance Hall Thruster Support System

    Science.gov (United States)

    Hesterman, Bryce

    2015-01-01

    Colorado Power Electronics (CPE) has built an innovative modular PPU for Hall thrusters, including discharge, magnet, heater and keeper supplies, and an interface module. This high-performance PPU offers resonant circuit topologies, magnetics design, modularity, and a stable and sustained operation during severe Hall effect thruster current oscillations. Laboratory testing has demonstrated discharge module efficiency of 96 percent, which is considerably higher than current state of the art.

  1. A Small Modular Laboratory Hall Effect Thruster

    Science.gov (United States)

    Lee, Ty Davis

    Electric propulsion technologies promise to revolutionize access to space, opening the door for mission concepts unfeasible by traditional propulsion methods alone. The Hall effect thruster is a relatively high thrust, moderate specific impulse electric propulsion device that belongs to the class of electrostatic thrusters. Hall effect thrusters benefit from an extensive flight history, and offer significant performance and cost advantages when compared to other forms of electric propulsion. Ongoing research on these devices includes the investigation of mechanisms that tend to decrease overall thruster efficiency, as well as the development of new techniques to extend operational lifetimes. This thesis is primarily concerned with the design and construction of a Small Modular Laboratory Hall Effect Thruster (SMLHET), and its operation on argon propellant gas. Particular attention was addressed at low-cost, modular design principles, that would facilitate simple replacement and modification of key thruster parts such as the magnetic circuit and discharge channel. This capability is intended to facilitate future studies of device physics such as anomalous electron transport and magnetic shielding of the channel walls, that have an impact on thruster performance and life. Preliminary results demonstrate SMLHET running on argon in a manner characteristic of Hall effect thrusters, additionally a power balance method was utilized to estimate thruster performance. It is expected that future thruster studies utilizing heavier though more expensive gases like xenon or krypton, will observe increased efficiency and stability.

  2. The Hall-induced stability of gravitating fluids

    Science.gov (United States)

    Karmakar, P. K.; Goutam, H. P.

    2018-05-01

    We analyze the stability behavior of low-density partially ionized self-gravitating magnetized unbounded dusty plasma fluid in the presence of the Hall diffusion effects (HDEs) in the non-ideal magnetohydrodynamic (MHD) equilibrium framework. The effects of inhomogeneous self-gravity are methodically included in the basic model tapestry. Application of the Fourier plane-wave perturbative treatment decouples the structuration representative parameters into a linear generalized dispersion relation (sextic) in a judicious mean-fluid approximation. The dispersion analysis shows that the normal mode, termed as the gravito-magneto-acoustic (GMA) mode, is drastically modified due to the HDEs. This mode is highly dispersive, and driven unstable by the Hall current resulting from the symmetry-breaking of electrons and ions relative to the magnetic field. The mode feature, which is derived from a modified induction with the positive Hall, is against the ideal MHD. It is further demonstrated that the HDEs play stabilizing roles by supporting the cloud against gravitational collapse. Provided that the HDEs are concurrently switched off, the collapse occurs on the global spatial scale due to enhanced inward accretion of the gravitating dust constituents. It is seen explicitly that the enhanced dust-charge leads to stabilizing effects. Besides, the Hall-induced fluctuations, as propagatory wave modes, exhibit both normal and anomalous dispersions. The reliability checkup of the entailed results as diverse corollaries and special cases are illustratively discussed in the panoptic light of the earlier paradigmatic predictions available in the literature.

  3. Reliability and Validity of Objective Structured Clinical Examination for Residents of Obstetrics and Gynecology at Kermanshah University of Medical Sciences

    Directory of Open Access Journals (Sweden)

    Nasrin Jalilian

    2012-11-01

    Full Text Available Introduction: Objective structured clinical examination (OSCE is used for the evaluation of the clinical competence in medicine for which it is essential to measure validity and reliability. This study aimed to investigate the validity and reliability of OSCE for residents of obstetrics and gynecology at Kermanshah University of Medical Sciences in 2011.Methods: A descriptive-correlation study was designed and the data of OSCE for obstetrics and gynecology were collected via learning behavior checklists in method stations and multiple choice questions in question stations. The data were analyzed through Pearson correlation coefficient and Cronbach's alpha, using SPSS software (version 16. To determine the criterion validity, correlation of OSCE scores with scores of resident promotion test, direct observation of procedural skills, and theoretical knowledge was determined; for reliability, however, Cronbach's alpha was used. Total sample consisted of 25 participants taking part in 14 stations. P value of less than 0.05 was considered as significant.Results: The mean OSCE scores was 22.66 (±6.85. Criterion validity of the stations with resident promotion theoretical test, first theoretical knowledge test, second theoretical knowledge, and direct observation of procedural skills (DOPS was 0.97, 0.74, 0.49, and 0.79, respectively. In question stations, criterion validity was 0.15, and total validity of OSCE was 0.77.Conclusion: Findings of the present study indicated acceptable validity and reliability of OSCE for residents of obstetrics and gynecology.

  4. Factors associated with burnout syndrome in medical residents of a university hospital

    Directory of Open Access Journals (Sweden)

    Pedro Alves da Cruz Gouveia

    Full Text Available Summary Objective: To determine the prevalence of burnout syndrome among resident physicians of various specialties and to evaluate associated factors. Method: The Maslach Burnout Inventory questionnaire and a sociodemographic questionnaire were used to evaluate factors associated with the syndrome. Burnout was defined as the association of high emotional exhaustion, depersonalization and low professional achievement. Multivariate analysis was performed after adjustment of the Poisson model with the identification of risk factors and calculation of prevalence ratios (PR. Of the 250 resident physicians registered with Hospital das Clínicas of Pernambuco, 129 participated in the study. Results: In the three domains that characterize burnout syndrome, we found a low level of professional achievement in 94.6% of resident physicians interviewed, a high level of depersonalization in 31.8%, and 59.7% with a high level of emotional exhaustion. The prevalence of burnout was 27.9%. Having suffered a stressful event in the last six months (PR: 8.10; 95CI 1.2-57.2 and being a student of surgical specialty (PR: 1.99; 95CI 1.2-3.3 were independently associated with burnout. Conclusion: The prevalence of burnout found in resident physicians is in accordance with previous Brazilian studies. Residents of surgical specialties and those who suffered some stressful event were identified as susceptible in this study. The early identification of risk factors is fundamental for the implementation of preventive measures against burnout syndrome.

  5. 3D Quantum Hall Effect of Fermi Arc in Topological Semimetals

    Science.gov (United States)

    Wang, C. M.; Sun, Hai-Peng; Lu, Hai-Zhou; Xie, X. C.

    2017-09-01

    The quantum Hall effect is usually observed in 2D systems. We show that the Fermi arcs can give rise to a distinctive 3D quantum Hall effect in topological semimetals. Because of the topological constraint, the Fermi arc at a single surface has an open Fermi surface, which cannot host the quantum Hall effect. Via a "wormhole" tunneling assisted by the Weyl nodes, the Fermi arcs at opposite surfaces can form a complete Fermi loop and support the quantum Hall effect. The edge states of the Fermi arcs show a unique 3D distribution, giving an example of (d -2 )-dimensional boundary states. This is distinctly different from the surface-state quantum Hall effect from a single surface of topological insulator. As the Fermi energy sweeps through the Weyl nodes, the sheet Hall conductivity evolves from the 1 /B dependence to quantized plateaus at the Weyl nodes. This behavior can be realized by tuning gate voltages in a slab of topological semimetal, such as the TaAs family, Cd3 As2 , or Na3Bi . This work will be instructive not only for searching transport signatures of the Fermi arcs but also for exploring novel electron gases in other topological phases of matter.

  6. A Survey on the Attitude of Professors & Residents of Clinical Wards about Disclosing the Results of Diagnoses for Incurable Patients at Urmia University of Medical Sciences

    Directory of Open Access Journals (Sweden)

    SH Miri Ghaffarzadeh

    2012-05-01

    Full Text Available

    Background and Objectives: One of the most important and complicated problems in medical ethics is to disclose the full truth about diagnosis of incurable diseases which leads to death, and each therapist may be encountered with it during the years of medical profession.

    The aim of this study was to survey on attitude of professors and residents of clinical wards to disclose the diagnosis for incurable patients leading to death.

     

    Methods: In this descriptive study, sampling was carried out by a survey. All faculty members and their residents of teaching hospitals of Urmia University of Medical Sciences, Urmia, Iran, were surveyed as sample in 2007. Of 145 subjects, 138 responded to the questionnaire. The collected data were analyzed using Pearson and Spearman correlation tests with a p≤0.05 being considered as significant.

     

    Results: In this study, the tendency to disclose the diagnosis among faculty members and residents was 64.63%. Also, there was no significant relation between age, sex, university degree, educational field, years of service of the faculty members and residents of clinical wards with the tendency for telling the truth to incurable patients.

     

    Conclusion: Final analyses revealed that the faculty members and clinical residents of different fields in terms of diagnosis disclosure do not have a definite idea. However, the majority of them agree to disclose the full truth about diagnoses.

     

  7. Mary E. Hall: Dawn of the Professional School Librarian

    Science.gov (United States)

    Alto, Teresa

    2012-01-01

    A century ago, a woman named Mary E. Hall convinced school leaders of the need for the professional school librarian--a librarian who cultivated a love of reading, academic achievement, and independent learning skills. After graduating from New York City's Pratt Institute Library School in 1895, Hall developed her vision for the high school…

  8. Acoustics in rock and pop music halls

    DEFF Research Database (Denmark)

    Larsen, Niels Werner; Thompson, Eric Robert; Gade, Anders Christian

    2007-01-01

    The existing body of literature regarding the acoustic design of concert halls has focused almost exclusively on classical music, although there are many more performances of rhythmic music, including rock and pop. Objective measurements were made of the acoustics of twenty rock music venues...... in Denmark and a questionnaire was used in a subjective assessment of those venues with professional rock musicians and sound engineers. Correlations between the objective and subjective results lead, among others, to a recommendation for reverberation time as a function of hall volume. Since the bass...

  9. Experimental and theoretical studies of cylindrical Hall thrusters

    International Nuclear Information System (INIS)

    Smirnov, Artem; Raitses, Yegeny; Fisch, Nathaniel J.

    2007-01-01

    The Hall thruster is a mature electric propulsion device that holds considerable promise in terms of the propellant saving potential. The annular design of the conventional Hall thruster, however, does not naturally scale to low power. The efficiency tends to be lower and the lifetime issues are more aggravated. Cylindrical geometry Hall thrusters have lower surface-to-volume ratio than conventional thrusters and, thus, seem to be more promising for scaling down. The cylindrical Hall thruster (CHT) is fundamentally different from the conventional design in the way the electrons are confined and the ion space charge is neutralized. The performances of both the large (9-cm channel diameter, 600-1000 W) and miniaturized (2.6-cm channel diameter, 50-300 W) CHTs are comparable with those of the state-of-the-art conventional (annular) design Hall thrusters of similar sizes. A comprehensive experimental and theoretical study of the CHT physics has been conducted, addressing the questions of electron cross-field transport, propellant ionization, plasma-wall interaction, and formation of the electron distribution function. Probe measurements in the harsh plasma environment of the microthruster were performed. Several interesting effects, such as the unusually high ionization efficiency and enhanced electron transport, were observed. Kinetic simulations suggest the existence of the strong fluctuation-enhanced electron diffusion and predict the non-Maxwellian shape of the electron distribution function. Through the acquired understanding of the new physics, ways for further optimization of this means for low-power space propulsion are suggested. Substantial flexibility in the magnetic field configuration of the CHT is the key tool in achieving the high-efficiency operation

  10. Assessment of perceived needs and preferences with regard to the education of residents in Medical Ethics in King Abdulaziz University Hospital.

    Science.gov (United States)

    Ghamri, Ranya A; Al-Raddadi, Rajaa M

    2017-01-01

    Medical ethics is the branch of ethics that deals with moral issues in medical practice. Many postgraduate training programs have developed educational interventions in ethics to meet accreditation standards and prepare learners for certification examinations and clinical practice. The aim of this study was to assess the attitude of residents in King Abdulaziz University Hospital (KAUH) toward the need for ethics education and identify the most effective methods of teaching ethical issues. A cross-sectional study of residents in different specialties at KAUH was conducted using a self-administered questionnaire. The questionnaire consisted of four parts: demographic data, assessment of the educational need for ethics education, assessment of the impact of various learning methods, and assessment of the need for ethically important practices and behavior. SPSS version 16.0 was used for data entry and analysis. Descriptive analysis included frequency distribution, percentages, mean, and standard deviation (SD); Chi-square test and t -test were employed to determine statistical significance. Eighty-eight of the 102 residents invited to participate in the study returned completed questionnaires, providing a response rate of 86.3%. Their ages ranged between 24 and 38 years with a mean of 27.7 (standard deviation 2.8) years. Approximately two-thirds of the residents (65.9%) agreed that medical ethics can be taught and learned while only 19.3% of them disagreed. The most effective methods of ethical education according to the residents were discussion groups of peers led by a knowledgeable clinician (78.4%), clinical rounds (72.7%), and an incorporation of ethical issues into lectures and teaching rounds (69.3%). This study documents the importance residents placed on ethics education directed at practical, real-world dilemmas and ethically important professional developmental issues.

  11. Novel Hall sensors developed for magnetic field imaging systems

    International Nuclear Information System (INIS)

    Cambel, Vladimir; Karapetrov, Goran; Novosad, Valentyn; Bartolome, Elena; Gregusova, Dagmar; Fedor, Jan; Kudela, Robert; Soltys, Jan

    2007-01-01

    We report here on the fabrication and application of novel planar Hall sensors based on shallow InGaP/AlGaAs/GaAs heterostructure with a two-dimensional electron gas (2DEG) as an active layer. The sensors are developed for two kinds of experiments. In the first one, magnetic samples are placed directly on the Hall sensor. Room temperature experiments of permalloy objects evaporated onto the sensor are presented. In the second experiment, the sensor scans close over a multigranular superconducting sample prepared on a YBCO thin film. Large-area and high-resolution scanning experiments were performed at 4.2 K with the Hall probe scanning system in a liquid helium flow cryostat

  12. DETERMINANTS OF SPECIALTY CHOICE OF RESIDENT DOCTORS; CASE STUDY--AMONG RESIDENT DOCTORS IN NIGERIA.

    Science.gov (United States)

    Osuoji, Roland I; Adebanji, Atinuke; Abdulsalam, Moruf A; Oludara, Mobolaji A; Abolarinwa, Abimbola A

    2015-01-01

    This study examined medical specialty selection by Nigerian resident doctors using a marketing research approach to determine the selection criteria and the role of perceptions, expected remuneration, and job placement prospects of various specialties in the selection process. Data were from the Community of residents from April 2014 to July 2014. The cohort included 200 residents, but only 171 had complete information. Data were obtained from a cross section of resident doctors in the Lagos State University Teaching Hospital and at the 2014 Ordinary General Meeting of the National Association of Resident Doctors(NARD) where representatives from over 50 Teaching hospitals in Nigeria attended. Using a client behaviour model as a framework, a tripartite questionnaire was designed and administered to residents to deduce information on their knowledge about and interests in various specialties, their opinions of sixteen specialties, and the criteria they used in specialty selection. A total of 171 (85.5%) questionnaires were returned. ln many instances, consistency between selection criteria and perceptions of a specialty were accompanied by interest in pursuing the specialty. Job security, job availability on completion of programme, duration of training and qualifying examinations were highly correlated with p value marketing research concepts for medical specialty selection (Weissmanet al 2012) stipulates that choice of speciality is influenced by criteria and perception. This study shows that job security expected financial remuneration, and examination requirements for qualification are major determinants of the choice of speciality for residents.

  13. Hall effect in noncommutative coordinates

    International Nuclear Information System (INIS)

    Dayi, Oemer F.; Jellal, Ahmed

    2002-01-01

    We consider electrons in uniform external magnetic and electric fields which move on a plane whose coordinates are noncommuting. Spectrum and eigenfunctions of the related Hamiltonian are obtained. We derive the electric current whose expectation value gives the Hall effect in terms of an effective magnetic field. We present a receipt to find the action which can be utilized in path integrals for noncommuting coordinates. In terms of this action we calculate the related Aharonov-Bohm phase and show that it also yields the same effective magnetic field. When magnetic field is strong enough this phase becomes independent of magnetic field. Measurement of it may give some hints on spatial noncommutativity. The noncommutativity parameter θ can be tuned such that electrons moving in noncommutative coordinates are interpreted as either leading to the fractional quantum Hall effect or composite fermions in the usual coordinates

  14. Judy Estes Hall (1940-2015).

    Science.gov (United States)

    Sammons, Morgan T; Boucher, Andrew

    2016-01-01

    Presents an obituary for Judy Estes Hall, who passed away on November 24, 2015. Hall served as the Executive Officer of the National Register of Health Service Psychologists until her retirement in 2013. She is a recognized expert in the development of education and training standards for the profession of psychology, she also made significant contributions in the field of international psychology, where she was a renowned expert in cross-national credentialing and an advocate for commonality in licensing standards. She was the coauthor of one edited volume and author of more than 60 journal articles, book chapters, and professional publications. A passionate advocate for the advancement of women in psychology, a devoted mother and grandmother, a connoisseur of wine and international traveler extraordinaire, she touched the personal and professional lives of many. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  15. Effect of hall currents on thermal instability of dusty couple stress fluid

    Directory of Open Access Journals (Sweden)

    Aggarwal Amrish Kumar

    2016-09-01

    Full Text Available In this paper, effect of Hall currents on the thermal instability of couple-stress fluid permeated with dust particles has been considered. Following the linearized stability theory and normal mode analysis, the dispersion relation is obtained. For the case of stationary convection, dust particles and Hall currents are found to have destabilizing effect while couple stresses have stabilizing effect on the system. Magnetic field induced by Hall currents has stabilizing/destabilizing effect under certain conditions. It is found that due to the presence of Hall currents (hence magnetic field, oscillatory modes are produced which were non-existent in their absence.

  16. Electron Cross-field Transport in a Miniaturized Cylindrical Hall Thruster

    International Nuclear Information System (INIS)

    Smirnov Artem; Raitses Yevgeny; Fisch Nathaniel J

    2005-01-01

    Conventional annular Hall thrusters become inefficient when scaled to low power. Cylindrical Hall thrusters, which have lower surface-to-volume ratio, are more promising for scaling down. They presently exhibit performance comparable with conventional annular Hall thrusters. The present paper gives a review of the experimental and numerical investigations of electron crossfield transport in the 2.6 cm miniaturized cylindrical Hall thruster (100 W power level). We show that, in order to explain the discharge current observed for the typical operating conditions, the electron anomalous collision frequency ν b has to be on the order of the Bohm value, ν B ∼ ω c /16. The contribution of electron-wall collisions to cross-field transport is found to be insignificant. The optimal regimes of thruster operation at low background pressure (below 10 -5 Torr) in the vacuum tank appear to be different from those at higher pressure (∼ 10 -4 Torr)

  17. Suggested Steps to Make Campuses More Trans-Inclusive

    Science.gov (United States)

    Beemyn, Brett Genny; Domingue, Andrea; Pettitt, Jessica; Smith, Todd

    2005-01-01

    To assist colleges and universities in becoming more supportive of transgender people, the authors, who work in campus LGBT student services, offer practical recommendations in areas where gender-variant students, staff, and faculty are likely to encounter discrimination. These areas include health care, residence halls, bathrooms, locker rooms,…

  18. Magnetotransport properties of 8-Pmmn borophene: effects of Hall field and strain.

    Science.gov (United States)

    Islam, S K Firoz

    2018-07-11

    The polymorph of 8-Pmmn borophene is an anisotropic Dirac material with tilted Dirac cones at two valleys. The tilting of the Dirac cones at two valleys are in opposite directions, which manifests itself via the valley dependent Landau levels in presence of an in-plane electric field (Hall field). The valley dependent Landau levels cause valley polarized magnetotransport properties in presence of the Hall field, which is in contrast to the monolayer graphene with isotropic non-tilted Dirac cones. The longitudinal conductivity and Hall conductivity are evaluated by using linear response theory in low temperature regime. An analytical approximate form of the longitudinal conductivity is also obtained. It is observed that the tilting of the Dirac cones amplifies the frequency of the longitudinal conductivity oscillation (Shubnikov-de Haas). On the other hand, the Hall conductivity exhibits graphene-like plateaus except the appearance of valley dependent steps which are purely attributed to the Hall field induced lifting of the valley degeneracy in the Landau levels. Finally we look into the different cases when the Hall field is applied to the strained borophene and find that valley dependency is fully dominated by strain rather than Hall field. Another noticeable point is that if the real magnetic field is replaced by the strain induced pseudo magnetic field then the electric field looses its ability to cause valley polarized transport.

  19. Can Medical School Performance Predict Residency Performance? Resident Selection and Predictors of Successful Performance in Obstetrics and Gynecology

    Science.gov (United States)

    Stohl, Hindi E.; Hueppchen, Nancy A.; Bienstock, Jessica L.

    2010-01-01

    Background During the evaluation process, Residency Admissions Committees typically gather data on objective and subjective measures of a medical student's performance through the Electronic Residency Application Service, including medical school grades, standardized test scores, research achievements, nonacademic accomplishments, letters of recommendation, the dean's letter, and personal statements. Using these data to identify which medical students are likely to become successful residents in an academic residency program in obstetrics and gynecology is difficult and to date, not well studied. Objective To determine whether objective information in medical students' applications can help predict resident success. Method We performed a retrospective cohort study of all residents who matched into the Johns Hopkins University residency program in obstetrics and gynecology between 1994 and 2004 and entered the program through the National Resident Matching Program as a postgraduate year-1 resident. Residents were independently evaluated by faculty and ranked in 4 groups according to perceived level of success. Applications from residents in the highest and lowest group were abstracted. Groups were compared using the Fisher exact test and the Student t test. Results Seventy-five residents met inclusion criteria and 29 residents were ranked in the highest and lowest quartiles (15 in highest, 14 in lowest). Univariate analysis identified no variables as consistent predictors of resident success. Conclusion In a program designed to train academic obstetrician-gynecologists, objective data from medical students' applications did not correlate with successful resident performance in our obstetrics-gynecology residency program. We need to continue our search for evaluation criteria that can accurately and reliably select the medical students that are best fit for our specialty. PMID:21976076

  20. Anode Fall Formation in a Hall Thruster

    International Nuclear Information System (INIS)

    Dorf, Leonid A.; Raitses, Yevgeny F.; Smirnov, Artem N.; Fisch, Nathaniel J.

    2004-01-01

    As was reported in our previous work, accurate, nondisturbing near-anode measurements of the plasma density, electron temperature, and plasma potential performed with biased and emissive probes allowed the first experimental identification of both electron-repelling (negative anode fall) and electron-attracting (positive anode fall) anode sheaths in Hall thrusters. An interesting new phenomenon revealed by the probe measurements is that the anode fall changes from positive to negative upon removal of the dielectric coating, which appears on the anode surface during the course of Hall thruster operation. As reported in the present work, energy dispersion spectroscopy analysis of the chemical composition of the anode dielectric coating indicates that the coating layer consists essentially of an oxide of the anode material (stainless steel). However, it is still unclear how oxygen gets into the thruster channel. Most importantly, possible mechanisms of anode fall formation in a Hall thruster with a clean and a coated anodes are analyzed in this work; practical implication of understanding the general structure of the electron-attracting anode sheath in the case of a coated anode is also discussed

  1. Higher (odd dimensional quantum Hall effect and extended dimensional hierarchy

    Directory of Open Access Journals (Sweden)

    Kazuki Hasebe

    2017-07-01

    Full Text Available We demonstrate dimensional ladder of higher dimensional quantum Hall effects by exploiting quantum Hall effects on arbitrary odd dimensional spheres. Non-relativistic and relativistic Landau models are analyzed on S2k−1 in the SO(2k−1 monopole background. The total sub-band degeneracy of the odd dimensional lowest Landau level is shown to be equal to the winding number from the base-manifold S2k−1 to the one-dimension higher SO(2k gauge group. Based on the chiral Hopf maps, we clarify the underlying quantum Nambu geometry for odd dimensional quantum Hall effect and the resulting quantum geometry is naturally embedded also in one-dimension higher quantum geometry. An origin of such dimensional ladder connecting even and odd dimensional quantum Hall effects is illuminated from a viewpoint of the spectral flow of Atiyah–Patodi–Singer index theorem in differential topology. We also present a BF topological field theory as an effective field theory in which membranes with different dimensions undergo non-trivial linking in odd dimensional space. Finally, an extended version of the dimensional hierarchy for higher dimensional quantum Hall liquids is proposed, and its relationship to quantum anomaly and D-brane physics is discussed.

  2. The evaluation of burnout and job satisfaction levels in residents of pediatrics.

    Science.gov (United States)

    Anıl, Murat; Yurtseven, Ali; Yurtseven, İlkay; Ülgen, Mevlüt; Anıl, Ayşe Berna; Helvacı, Mehmet; Aksu, Nejat

    2017-06-01

    The aim of the study was to examine the level of job-related burnout and the level of job satisfaction among residents of pediatrics. A total of 102 residents of pediatrics who were trained in two Ministry of Health teaching and research hospitals and in two university hospitals in Izmir were included in the study. Demographic data (age, sex), lifestyle (living with parents or not, marital status, number of children) and professional characteristics (total time spent in profession, time spent in residency, number of night shifts per month, institution type: teaching hospital/university) were collected. Maslach Burnout Inventory (subscales: emotional exhaustion, desensitization, personal accomplishment) and Minnesota Satisfaction Questionnaire were used. High levels of emotional exhaustion and desensitization, and low levels of personal accomplishment and job satisfaction were found in residents of pediatrics. Low levels of emotional exhaustion in teaching and research hospitals and low levels of desensitization in university hospitals were determined (pjob satisfaction levels and a negative correlation between age and emotional exhaustion levels (pjob satisfaction. Emotional exhaustion is more common in teaching and research hospitals and desensitization is more common in universities. Younger age, lower seniority, and the higher number of work-shift increases the burnout.

  3. Fractional statistics and fractional quantized Hall effect. Revision

    International Nuclear Information System (INIS)

    Tao, R.; Wu, Y.S.

    1984-01-01

    We suggest that the origin of the odd denominator rule observed in the fractional quantized Hall effect (FQHE) may lie in fractional statistics which governs quasiparticles in FQHE. A theorem concerning statistics of clusters of quasiparticles implies that fractional statistics does not allow coexistence of a large number of quasiparticles at fillings with an even denominator. Thus no Hall plateau can be formed at these fillings, regardless of the presence of an energy gap. 15 references

  4. Evaluation of Pressure Changes in HANARO Reactor Hall after a Reactor Shutdown

    International Nuclear Information System (INIS)

    Han, Geeyang; Han, Jaesam; Ahn, Gukhoon; Jung, Hoansung

    2013-01-01

    The major objective of this work is intended to evaluate the characteristics of the thermal behavior regarding how the decay heat will be affected by the reactor hall pressure change and the increase of pool water temperature induced in the primary coolant after a reactor shutdown. The particular reactor pool water temperature at the surface where it is evaporated owing to the decay heat resulting in the local heat transfer rate is related to the pressure change response in the reactor hall associated with the primary cooling system because of the reduction of the heat exchanger to remove the heat. The increase in the pool water temperature is proportional to the heat transfer rate in the reactor pool. Consequently, any limit on the reactor pool water temperature imposes a corresponding limit on the reactor hall pressure. At HANARO, the decay heat after a reactor shutdown is mainly removed by the natural circulation cooling in the reactor pool. This paper is written for the safety feature of the pressure change related leakage rate from the reactor hall. The calculation results show that the increase of pressure in the reactor hall will not cause any serious problems to the safety limits although the reactor hall pressure is slightly increased. Therefore, it was concluded that the pool water temperature increase is not so rapid as to cause the pressure to vary significantly in the reactor hall. Furthermore, the mathematical model developed in this work can be a useful analytical tool for scoping and parametric studies in the area of thermal transient analysis, with its proper representation of the interaction between the temperature and pressure in the reactor hall

  5. Admittance of multiterminal quantum Hall conductors at kilohertz frequencies

    International Nuclear Information System (INIS)

    Hernández, C.; Consejo, C.; Chaubet, C.; Degiovanni, P.

    2014-01-01

    We present an experimental study of the low frequency admittance of quantum Hall conductors in the [100 Hz, 1 MHz] frequency range. We show that the frequency dependence of the admittance of the sample strongly depends on the topology of the contacts connections. Our experimental results are well explained within the Christen and Büttiker approach for finite frequency transport in quantum Hall edge channels taking into account the influence of the coaxial cables capacitance. In the Hall bar geometry, we demonstrate that there exists a configuration in which the cable capacitance does not influence the admittance measurement of the sample. In this case, we measure the electrochemical capacitance of the sample and observe its dependence on the filling factor

  6. Admittance of multiterminal quantum Hall conductors at kilohertz frequencies

    Energy Technology Data Exchange (ETDEWEB)

    Hernández, C. [Departamento de Física, Universidad Militar Nueva Granada, Carrera 11 101-80 Bogotá D.C. (Colombia); Consejo, C.; Chaubet, C., E-mail: christophe.chaubet@univ-montp2.fr [Université Montpellier 2, Laboratoire Charles Coulomb UMR5221, F-34095 Montpellier, France and CNRS, Laboratoire Charles Coulomb UMR5221, F-34095 Montpellier (France); Degiovanni, P. [Université de Lyon, Fédération de Physique Andrée Marie Ampère, CNRS, Laboratoire de Physique de l' Ecole Normale Supérieure de Lyon, 46 allée d' Italie, 69364 Lyon Cedex 07 (France)

    2014-03-28

    We present an experimental study of the low frequency admittance of quantum Hall conductors in the [100 Hz, 1 MHz] frequency range. We show that the frequency dependence of the admittance of the sample strongly depends on the topology of the contacts connections. Our experimental results are well explained within the Christen and Büttiker approach for finite frequency transport in quantum Hall edge channels taking into account the influence of the coaxial cables capacitance. In the Hall bar geometry, we demonstrate that there exists a configuration in which the cable capacitance does not influence the admittance measurement of the sample. In this case, we measure the electrochemical capacitance of the sample and observe its dependence on the filling factor.

  7. A highly sensitive CMOS digital Hall sensor for low magnetic field applications.

    Science.gov (United States)

    Xu, Yue; Pan, Hong-Bin; He, Shu-Zhuan; Li, Li

    2012-01-01

    Integrated CMOS Hall sensors have been widely used to measure magnetic fields. However, they are difficult to work with in a low magnetic field environment due to their low sensitivity and large offset. This paper describes a highly sensitive digital Hall sensor fabricated in 0.18 μm high voltage CMOS technology for low field applications. The sensor consists of a switched cross-shaped Hall plate and a novel signal conditioner. It effectively eliminates offset and low frequency 1/f noise by applying a dynamic quadrature offset cancellation technique. The measured results show the optimal Hall plate achieves a high current related sensitivity of about 310 V/AT. The whole sensor has a remarkable ability to measure a minimum ± 2 mT magnetic field and output a digital Hall signal in a wide temperature range from -40 °C to 120 °C.

  8. Edge states and integer quantum Hall effect in topological insulator thin films.

    Science.gov (United States)

    Zhang, Song-Bo; Lu, Hai-Zhou; Shen, Shun-Qing

    2015-08-25

    The integer quantum Hall effect is a topological state of quantum matter in two dimensions, and has recently been observed in three-dimensional topological insulator thin films. Here we study the Landau levels and edge states of surface Dirac fermions in topological insulators under strong magnetic field. We examine the formation of the quantum plateaux of the Hall conductance and find two different patterns, in one pattern the filling number covers all integers while only odd integers in the other. We focus on the quantum plateau closest to zero energy and demonstrate the breakdown of the quantum spin Hall effect resulting from structure inversion asymmetry. The phase diagrams of the quantum Hall states are presented as functions of magnetic field, gate voltage and chemical potential. This work establishes an intuitive picture of the edge states to understand the integer quantum Hall effect for Dirac electrons in topological insulator thin films.

  9. Impact of co-investigators on pharmacy resident research publication

    Directory of Open Access Journals (Sweden)

    Stranges PM

    2017-06-01

    Full Text Available Objective: To explore influences of co-investigators on the successful publication of a pharmacy residency project. Methods: We analyzed published and non-published research presented at a regional pharmacy conference. Abstracts were matched 1:1 based on state and abstract year. We assessed university affiliation, number, degree, and H-Index of co-investigators on the abstract. Descriptive and inferential analyses were used to identify variables associated with resident publication. Results: University-affiliated programs (p=0.015, highest H-Index of a non-physician co-investigator (p=0.002, and positive H-Index (≥1 of a non-physician co-investigator (p=0.017 were significant predictors of resident publication on univariate analyses. There were no differences in the number of co-investigators (p=0.051, projects with physician co-investigators (p=1.000, or projects with Doctor of Philosophy (PhD or Master of Science (MS co-investigators (p=0.536 between published and non-published projects. Multivariate analysis found that the highest H-index of non-physician co-investigator remained significant as a predictor to resident publication (odds ratio (OR 1.09, 95% Confidence Interval (CI 1.01-1.17. Conclusions: The quality of co-investigators, as measured by an increasing H-Index, is associated with the successful publication of residency projects. More emphasis may need to be placed on resident research co-investigator selection and training to prepare pharmacy residents for research and scholarly activity.

  10. Spin-Hall nano-oscillator: A micromagnetic study

    Energy Technology Data Exchange (ETDEWEB)

    Giordano, A.; Azzerboni, B.; Finocchio, G. [Department of Electronic Engineering, Industrial Chemistry and Engineering, University of Messina, C.da di Dio, I-98166 Messina (Italy); Carpentieri, M. [Department of Electrical and Information Engineering, Politecnico of Bari, via E. Orabona 4, I-70125 Bari (Italy); Laudani, A. [Department of Engineering, University of Roma Tre, via V. Volterra 62, I-00146 Roma (Italy); Gubbiotti, G. [Istituto Officina dei Materiali del CNR (CNR-IOM), Unità di Perugia c/o Dipartimento di Fisica e Geologia, Via A. Pascoli, 06123 Perugia (Italy)

    2014-07-28

    This Letter studies the dynamical behavior of spin-Hall nanoscillators from a micromagnetic point of view. The model parameters have been identified by reproducing recent experimental data quantitatively. Our results indicate that a strongly localized mode is observed for in-plane bias fields such as in the experiments, while predict the excitation of an asymmetric propagating mode for large enough out-of plane bias field similarly to what observed in spin-torque nanocontact oscillators. Our findings show that spin-Hall nanoscillators can find application as spin-wave emitters for magnonic applications where spin waves are used for transmission and processing information on nanoscale.

  11. Competencies for first year residents - physicians' views from medical schools with different undergraduate curricula.

    Science.gov (United States)

    Fürstenberg, Sophie; Schick, Kristina; Deppermann, Jana; Prediger, Sarah; Berberat, Pascal O; Kadmon, Martina; Harendza, Sigrid

    2017-09-07

    Frameworks like the CanMEDS model depicting professional roles and specific professional activities provide guidelines for postgraduate education. When medical graduates start their residency, they should possess certain competencies related to communication, management and professionalism while other competencies will be refined during postgraduate training. Our study aimed to evaluate the relevance of different competencies for a first year resident required for entrustment decision from the perspective of physicians from medical faculties with different undergraduate medical curricula. Nine hundred fifty-two surgeons and internists from three medical schools with different undergraduate medical curricula were invited to rank 25 competencies according to their relevance for first year residents. The rankings were compared between universities, specialties, physicians' positions, and gender. Two hundred two physicians participated, 76 from Hamburg University, 44 from Oldenburg University, and 82 from Technical University Munich. No significant differences were found regarding the top 10 competencies relevant for first year residents between the universities. 'Responsibility' was the competency with the highest rank overall. Internists ranked 'Structure, work planning and priorities' higher while surgeons ranked 'Verbal communication with colleagues and supervisors' higher. Consultants evaluated 'Active listening to patients' more important than department directors and residents. Female physicians ranked 'Verbal communication with colleagues and supervisors' and 'Structure, work planning and priorities' significantly higher while male physicians ranked 'Scientifically and empirically grounded method of working' significantly higher. Physicians from universities with different undergraduate curricula principally agreed on the competencies relevant for first year residents. Some differences between physicians from different positions, specialties, and gender were

  12. Hall effect on magnetohydrodynamic instabilities at an elliptic magnetic stagnation line

    Science.gov (United States)

    Spies, Günther O.; Faghihi, Mustafa

    1987-06-01

    To answer the question whether the Hall effect removes the unphysical feature of ideal magnetohydrodynamics of predicting small wavelength kink instabilities at any elliptic magnetic stagnation line, a normal mode analysis is performed of the motion of an incompressible Hall fluid about cylindrical Z-pinch equilibria with circular cross sections. The eigenvalue loci in the complex frequency plane are derived for the equilibrium with constant current density. Every particular mode becomes stable as the Hall parameter exceeds a critical value. This value, however, depends on the mode such that it increases to infinity as the ideal growth rate decreases to zero, implying that there always remains an infinite number of slowly growing instabilities. Correspondingly, the stability criterion for equilibria with arbitrary current distributions is independent of the Hall parameter.

  13. Hall effect on magnetohydrodynamic instabilities at an elliptic magnetic stagnation line

    International Nuclear Information System (INIS)

    Spies, G.O.; Faghihi, M.

    1987-01-01

    To answer the question whether the Hall effect removes the unphysical feature of ideal magnetohydrodynamics of predicting small wavelength kink instabilities at any elliptic magnetic stagnation line, a normal mode analysis is performed of the motion of an incompressible Hall fluid about cylindrical Z-pinch equilibria with circular cross sections. The eigenvalue loci in the complex frequency plane are derived for the equilibrium with constant current density. Every particular mode becomes stable as the Hall parameter exceeds a critical value. This value, however, depends on the mode such that it increases to infinity as the ideal growth rate decreases to zero, implying that there always remains an infinite number of slowly growing instabilities. Correspondingly, the stability criterion for equilibria with arbitrary current distributions is independent of the Hall parameter

  14. Influence of energy bands on the Hall effect in degenerate semiconductors

    International Nuclear Information System (INIS)

    Wu, Chhi-Chong; Tsai, Jensan

    1989-01-01

    The influence of energy bands on the Hall effect and transverse magnetoresistance has been investigated according to the scattering processes of carriers in degenerate semiconductors such as InSb. Results show that the Hall angle, Hall coefficient, and transverse magnetoresistance depend on the dc magnetic field for both parabolic and nonparabolic band structures of semiconductors and also depend on the scattering processes of carriers in semiconductors due to the energy-dependent relaxation time. From their numerical analysis for the Hall effect, it is shown that the conduction electrons in degenerate semiconductors play a major role for the carrier transport phenomenon. By comparing with experimental data of the transverse magnetoresistance, it shows that the nonparabolic band model is better in agreement with the experimental work than the parabolic band model of semiconductors

  15. 1000 Hours of Testing Completed on 10-kW Hall Thruster

    Science.gov (United States)

    Mason, Lee S.

    2001-01-01

    Between the months of April and August 2000, a 10-kW Hall effect thruster, designated T- 220, was subjected to a 1000-hr life test evaluation. Hall effect thrusters are propulsion devices that electrostatically accelerate xenon ions to produce thrust. Hall effect propulsion has been in development for many years, and low-power devices (1.35 kW) have been used in space for satellite orbit maintenance. The T-220, shown in the photo, produces sufficient thrust to enable efficient orbital transfers, saving hundreds of kilograms in propellant over conventional chemical propulsion systems. This test is the longest operation ever achieved on a high-power Hall thruster (greater than 4.5 kW) and is a key milestone leading to the use of this technology for future NASA, commercial, and military missions.

  16. Magnetically filtered Faraday probe for measuring the ion current density profile of a Hall thruster

    International Nuclear Information System (INIS)

    Rovey, Joshua L.; Walker, Mitchell L.R.; Gallimore, Alec D.; Peterson, Peter Y.

    2006-01-01

    The ability of a magnetically filtered Faraday probe (MFFP) to obtain the ion current density profile of a Hall thruster is investigated. The MFFP is designed to eliminate the collection of low-energy, charge-exchange (CEX) ions by using a variable magnetic field as an ion filter. In this study, a MFFP, Faraday probe with a reduced acceptance angle (BFP), and nude Faraday probe are used to measure the ion current density profile of a 5 kW Hall thruster operating over the range of 300-500 V and 5-10 mg/s. The probes are evaluated on a xenon propellant Hall thruster in the University of Michigan Large Vacuum Test Facility at operating pressures within the range of 4.4x10 -4 Pa Xe (3.3x10 -6 Torr Xe) to 1.1x10 -3 Pa Xe (8.4x10 -6 Torr Xe) in order to study the ability of the Faraday probe designs to filter out CEX ions. Detailed examination of the results shows that the nude probe measures a greater ion current density profile than both the MFFP and BFP over the range of angular positions investigated for each operating condition. The differences between the current density profiles obtained by each probe are attributed to the ion filtering systems employed. Analysis of the results shows that the MFFP, operating at a +5 A solenoid current, provides the best agreement with flight-test data and across operating pressures

  17. Physics Nobel Prize Goes to Tsui, Stormer and Laughlin for the Fractional Quantum Hall Effect

    International Nuclear Information System (INIS)

    Schwarzschild, Bertram

    1998-01-01

    This year's Nobel Prize in Physics is shared by Robert Laughlin (Stanford), Horst Stormer (Columbia University and Bell Laboratories) and Daniel Tsui (Princeton), for their roles in the discovery and explanation of the fractional quantum Hall effect. In 1982, when Stormer and Tsui were experimenters at Bell Labs, they and their colleague Arthur Gossard discovered this totally unexpected quantum effect in the transport properties of two‐dimensional electron gases at low temperature in strong magnetic fields.’ (See PHYSICS TODAY, July 1983, page 19.)

  18. Physics Nobel Prize Goes to Tsui, Stormer and Laughlin for the Fractional Quantum Hall Effect

    Energy Technology Data Exchange (ETDEWEB)

    Schwarzschild, Bertram

    1998-12-15

    This year's Nobel Prize in Physics is shared by Robert Laughlin (Stanford), Horst Stormer (Columbia University and Bell Laboratories) and Daniel Tsui (Princeton), for their roles in the discovery and explanation of the fractional quantum Hall effect. In 1982, when Stormer and Tsui were experimenters at Bell Labs, they and their colleague Arthur Gossard discovered this totally unexpected quantum effect in the transport properties of two‐dimensional electron gases at low temperature in strong magnetic fields.’ (See PHYSICS TODAY, July 1983, page 19.)

  19. Automated Podcasting System for Universities

    Directory of Open Access Journals (Sweden)

    Ypatios Grigoriadis

    2013-03-01

    Full Text Available This paper presents the results achieved at Graz University of Technology (TU Graz in the field of automating the process of recording and publishing university lectures in a very new way. It outlines cornerstones of the development and integration of an automated recording system such as the lecture hall setup, the recording hardware and software architecture as well as the development of a text-based search for the final product by method of indexing video podcasts. Furthermore, the paper takes a look at didactical aspects, evaluations done in this context and future outlook.

  20. Observation of the fractional quantum Hall effect in graphene.

    Science.gov (United States)

    Bolotin, Kirill I; Ghahari, Fereshte; Shulman, Michael D; Stormer, Horst L; Kim, Philip

    2009-11-12

    When electrons are confined in two dimensions and subject to strong magnetic fields, the Coulomb interactions between them can become very strong, leading to the formation of correlated states of matter, such as the fractional quantum Hall liquid. In this strong quantum regime, electrons and magnetic flux quanta bind to form complex composite quasiparticles with fractional electronic charge; these are manifest in transport measurements of the Hall conductivity as rational fractions of the elementary conductance quantum. The experimental discovery of an anomalous integer quantum Hall effect in graphene has enabled the study of a correlated two-dimensional electronic system, in which the interacting electrons behave like massless chiral fermions. However, owing to the prevailing disorder, graphene has so far exhibited only weak signatures of correlated electron phenomena, despite intense experimental and theoretical efforts. Here we report the observation of the fractional quantum Hall effect in ultraclean, suspended graphene. In addition, we show that at low carrier density graphene becomes an insulator with a magnetic-field-tunable energy gap. These newly discovered quantum states offer the opportunity to study correlated Dirac fermions in graphene in the presence of large magnetic fields.

  1. Quantifying Spin Hall Angles from Spin Pumping : Experiments and Theory

    NARCIS (Netherlands)

    Mosendz, O.; Pearson, J.E.; Fradin, F.Y.; Bauer, G.E.W.; Bader, S.D.; Hoffmann, A.

    2010-01-01

    Spin Hall effects intermix spin and charge currents even in nonmagnetic materials and, therefore, ultimately may allow the use of spin transport without the need for ferromagnets. We show how spin Hall effects can be quantified by integrating Ni80Fe20|normal metal (N) bilayers into a coplanar

  2. University Teachers' Self-Reflection on Their Academic Growth

    Science.gov (United States)

    Pedrosa-de-Jesus, Helena; Guerra, Cecília; Watts, Mike

    2017-01-01

    This study followed the academic growth of four university teachers, over a two-year period, with the intention of enhancing inquiry-based learning in practice. Data were generated within the natural settings of classrooms, laboratories and lecture halls, through the analysis of teaching materials, low-participation observation, informal…

  3. Beliefs versus Lived Experience: Gender Differences in Catholic College Students' Attitudes Concerning Premarital Sex and Contraception

    Science.gov (United States)

    Maher, Michael J.; Sever, Linda M.; Pichler, Shaun

    2008-01-01

    In April 2003, the researchers conducted a survey of undergraduate students living in residence halls at Loyola University Chicago. The survey contained twenty statements on issues currently discussed in the religious circles, especially the Catholic Church. The majority of both Catholic males and Catholic females disagreed with the statements,…

  4. [French residents' training in instrumental deliveries: A national survey].

    Science.gov (United States)

    Saunier, C; Raimond, E; Dupont, A; Pelissier, A; Bonneau, S; Gabriel, R; Graesslin, O

    2016-11-01

    To evaluate French residents in Obstetrics and Gynaecology's training in instrumental deliveries in 2015. We conducted a national descriptive survey among 758 residents between December 2014 and January 2015. Respondents were invited by email to specify their University Hospital, their current university term, the number of instrumental deliveries performed by vacuum extractor, forceps or spatulas, and whether they made systematic ultrasound exams before performing the extraction. Response rate was 34.7 % (n=263). There were important differences between regions in terms of type of instruments used. Vacuum extractor was the most commonly used instrument for instrumental deliveries by French residents (56.9 %), more than forceps (25.2 %) and spatulas (17.9 %). At the end of the residency, all the residents had been trained in instrumental deliveries with at least two instruments. The training of difficult techniques as well as their perfect control is required for instrumental deliveries. Yet, we are forced to note that there are substantial differences in the French residents' training in instrumental deliveries depending on their region. So, teaching at least two techniques seems essential as well as improving the training capacities and standardizing practices. A greater systematization of the teaching of the mechanics and obstetric techniques might be a solution to be considered too. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  5. Familial Pallister-Hall in adulthood.

    Science.gov (United States)

    Talsania, Mitali; Sharma, Rohan; Sughrue, Michael E; Scofield, R Hal; Lim, Jonea

    2017-10-01

    Pallister Hall syndrome is autosomal dominant disorder usually diagnosed in infants and children. Current diagnostic criteria include presence of hypothalamic hamartoma, post axial polydactyly and positive family history, but the disease has variable manifestations. Herein we report Pallister Hall syndrome diagnosed in a family where both patients were adults. A 59 year old man developed seizures 4 years prior to our evaluation of him, at which time imaging showed a hypothalamic hamartoma. The seizures were controlled medically. He did well until he had visual changes after a traumatic head injury. Repeat MRI showed slight expansion of the mass with formal visual field testing demonstrating bitemporal hemianopsia. There was no evidence of pituitary dysfunction except for large urine volume. He underwent surgery to debulk the hamartoma and the visual field defects improved. There was no hypopituitarism post-operatively, and the polydyspia resolved. His 29 year old daughter also had seizures and hypothalamic hamartoma. Both patients had had polydactyly with prior surgical correction in childhood. The daughter underwent genetic testing, which revealed a previously undescribed heterozygous single base pair deletion in exon 13 of the GLI3 gene causing a frameshift mutation. Further investigation into family history revealed multiple members in previous generations with polydactyly and/or seizures. Pallister-Hall syndrome is caused by an inherited autosomal dominant or de novo mutation in GLI3 gene. This rare syndrome has not had prevalence defined, however. Generally, diagnoses are made in the pediatric population. Our report adds to the few cases detected in adulthood.

  6. Hall effect in the two-dimensional Luttinger liquid

    International Nuclear Information System (INIS)

    Anderson, P.W.

    1991-01-01

    The temperature dependence of the Hall effect in the normal state is a commom theme of all the cuprate superconductors and has been one of the more puzzling observations on these puzzling materials. We describe a general scheme within the Luttinger liquid theory of these two-dimensional quantum fluids which corrrelates the anomalous Hall and resistivity observations on a wide variety of both pure and doped single crystals, especially the data in the accompanying Letter of Chien, Wang, and Ong

  7. History and Guideline of Emergency Medicine Residency Discipline in Shahid Beheshti University of Medical Sciences, Iran; Review of 2014

    Directory of Open Access Journals (Sweden)

    Majid Shojaee

    2014-09-01

    Full Text Available Introduction: Since many years ago several problems have been felt in emergency departments (ED of hospitals. In fact, none of physicians in the hospital have accepted the direct responsibility of patients’ management in the EDs and emergency wards of University centers have been managed by residents of various disciplines. Thus, the first line of therapy does not have guardian and several consultants with various specialists have been performed regarding patient’s management. The necessity of physician training was noticed for the first time in 1950 and after 24 years in 1974, the academic emergency medicine was established in United States of America (USA in response to people expectations for overnight accessibility to specialized and quality medical cares. It was performed with foundation of the first period of resident’s training in emergency medicine discipline at University of Cincinnati, Ohio. At beginning, specialists of different fields such as internal medicine, surgery, anesthesia, orthopedics, and neurosurgery initiated the training of emergency medicine residents together which could be responsible to most of referees. Finally, with formal accepting the specialty board in 1978, this field has been officially identified as the 23th discipline in USA. Today the EDs of most hospitals in European and American countries has been managing by emergency medicine specialists which leads to improve the quality of education and treatment, significantly. Also in Iran the request of establishing this major has been presented in the secretariat of the council for graduate medical education for the first time in 1996. This request was approved and principles of its initiating recognized officially by the ministry of health. But, considering to lack of an appropriate infrastructure, it postponed until 2000 that again this discipline was missioned for initiating to the council for graduate medical education by the minister and its outcome was

  8. Main Parameters Characterization of Bulk CMOS Cross-Like Hall Structures

    Directory of Open Access Journals (Sweden)

    Maria-Alexandra Paun

    2016-01-01

    Full Text Available A detailed analysis of the cross-like Hall cells integrated in regular bulk CMOS technological process is performed. To this purpose their main parameters have been evaluated. A three-dimensional physical model was employed in order to evaluate the structures. On this occasion, numerical information on the input resistance, Hall voltage, conduction current, and electrical potential distribution has been obtained. Experimental results for the absolute sensitivity, offset, and offset temperature drift have also been provided. A quadratic behavior of the residual offset with the temperature was obtained and the temperature points leading to the minimum offset for the three Hall cells were identified.

  9. Postoperative electrolyte management: Current practice patterns of surgeons and residents.

    Science.gov (United States)

    Angarita, Fernando A; Dueck, Andrew D; Azouz, Solomon M

    2015-07-01

    Managing postoperative electrolyte imbalances often is driven by dogma. To identify areas of improvement, we assessed the practice pattern of postoperative electrolyte management among surgeons and residents. An online survey was distributed among attending surgeons and surgical residents at the University of Toronto. The survey was designed according to a systematic approach for formulating self-administered questionnaires. Questions addressed workload, decision making in hypothetical clinical scenarios, and improvement strategies. Of 232 surveys distributed, 156 were completed (response rate: 67%). The majority stated that junior residents were responsible for managing electrolytes at 13 University of Toronto-affiliated hospitals. Supervision was carried out predominately by senior residents (75%). Thirteen percent reported management went unsupervised. Approximately 59% of residents were unaware how often attending surgeons assessed patients' electrolytes. Despite the majority of residents (53.7%) reporting they were never given tools or trained in electrolyte replacement, they considered themselves moderately or extremely confident. The management of hypothetical clinical scenarios differed between residents and attending surgeons. The majority (50.5%) of respondents considered that an electrolyte replacement protocol is the most appropriate improvement strategy. Electrolyte replacement represents an important component of surgeons' workload. Despite reporting that formal training in electrolyte management is limited, residents consider themselves competent; however, their practice is highly variable and often differs from pharmacologic-directed recommendations. Optimizing how postoperative electrolytes are managed in surgical wards requires building a framework that improves knowledge, training, and limits unnecessary interventions. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Spin Hall effect for anyons

    International Nuclear Information System (INIS)

    Dhar, S.; Basu, B.; Ghosh, Subir

    2007-01-01

    We explain the intrinsic spin Hall effect from generic anyon dynamics in the presence of external electromagnetic field. The free anyon is represented as a spinning particle with an underlying non-commutative configuration space. The Berry curvature plays a major role in the analysis

  11. Effects of surface and interface scattering on anomalous Hall effect in Co/Pd multilayers

    KAUST Repository

    Guo, Zaibing

    2012-09-27

    In this paper, we report the results of surface and interface scattering on anomalous Hall effect in Co/Pd multilayers with perpendicular magnetic anisotropy. The surface scattering effect has been extracted from the total anomalous Hall effect. By scaling surface scattering contribution with ρAHs∼ργss, the exponent γ has been found to decrease with the increase of surface scattering resistivity, which could account for the thickness-dependent anomalous Hall effect. Interface diffusion induced by rapid thermal annealing modifies not only the magnetization and longitudinal resistivity but also the anomalous Hall effect; a large exponent γ ∼ 5.7 has been attributed to interface scattering-dominated anomalous Hall effect.

  12. On-tip sub-micrometer Hall probes for magnetic microscopy prepared by AFM lithography

    International Nuclear Information System (INIS)

    Gregusova, D.; Martaus, J.; Fedor, J.; Kudela, R.; Kostic, I.; Cambel, V.

    2009-01-01

    We developed a technology of sub-micrometer Hall probes for future application in scanning hall probe microscopy (SHPM) and magnetic force microscopy (MFM). First, the Hall probes of ∼9-μm dimensions are prepared on the top of high-aspect-ratio GaAs pyramids with an InGaP/AlGaAs/GaAs active layer using wet-chemical etching and non-planar lithography. Then we show that the active area of planar Hall probes can be downsized to sub-micrometer dimensions by local anodic oxidation technique using an atomic force microscope. Such planar probes are tested and their noise and magnetic field sensitivity are evaluated. Finally, the two technologies are combined to fabricate sub-micrometer Hall probes on the top of high-aspect ratio mesa for future SHPM and MFM techniques.

  13. Room acoustic enhancement in a small hall with very low natural reverberation time

    DEFF Research Database (Denmark)

    Gade, Anders Christian

    1996-01-01

    natural combinations of room acoustic properties. Consequently, the natural reverberation time in a newly opened 350 seat multipurpose hall in Denmark was designed as low as 0.7 sec. Two different reverberation enhancement systems were considered and tested in the hall. The objective and subjective...... testing results are reported and compared with previous results obtained in another small hall supplied with a similar enhancement system. The results concerning 'realism' are also compared with acoustic properties found in 'natural' halls of different sizes and reverberation times.......In small multipurpose halls to be equipped with electronic reverberation enhancement systems, selecting a very low natural reverberation time is advantageous for several reasons. It will 1) reduce the risk of feedback, 2) increase the possible range of room acoustic variation and 3) allow for more...

  14. Orthopedic Resident Anatomy Review Course: A Collaboration between Anatomists and Orthopedic Surgeons

    Science.gov (United States)

    DeFriez, Curtis B.; Morton, David A.; Horwitz, Daniel S.; Eckel, Christine M.; Foreman, K. Bo; Albertine, Kurt H.

    2011-01-01

    A challenge for new residents and senior residents preparing for board examinations is refreshing their knowledge of basic science disciplines, such as human gross anatomy. The Department of Orthopaedics at the University of Utah School of Medicine has for many years held an annual Orthopedic Resident Anatomy Review Course during the summer months…

  15. The Hall coefficient: a tool for characterizing graphene field effect transistors

    International Nuclear Information System (INIS)

    Wehrfritz, Peter; Seyller, Thomas

    2014-01-01

    Graphene field effect transistors are considered as a candidate for future high-frequency applications. For their realization, the optimal combination of substrate, graphene preparation, and insulator deposition and composition is required. This optimization must be based on an in-depth characterization of the obtained graphene insulator metal (GIM) stack. Hall effect measurements are frequently employed to study such systems, thereby focussing primarily on the charge carrier mobility. In this work we show how an analysis of the sheet Hall coefficient can reveal further important properties of the GIM stack, like, e.g., the interface trap density and the spacial charge inhomogeneity. To that end, we provide an extensive description of the GIM diode, which leads to an accurate calculation of the sheet Hall coefficient dependent on temperature and gate voltage. The gate dependent inverse sheet Hall coefficient is discussed in detail before we introduce the concept of an equivalent temperature, which is a measure of the spacial charge inhomogeneity. In order to test the concept, we apply it to evaluate already measured Hall data taken from the literature. This evaluation allows us to determine the Drude mobility, even at the charge neutrality point, which is inaccessible with a simple one band Hall mobility analysis, and to shed light on the spacial charge inhomogeneity. The formalism is easily adaptable and provides experimentalists a powerful tool for the characterization of their graphene field effect devices. (paper)

  16. Overview of NASA Iodine Hall Thruster Propulsion System Development

    Science.gov (United States)

    Smith, Timothy D.; Kamhawi, Hani; Hickman, Tyler; Haag, Thomas; Dankanich, John; Polzin, Kurt; Byrne, Lawrence; Szabo, James

    2016-01-01

    NASA is continuing to invest in advancing Hall thruster technologies for implementation in commercial and government missions. The most recent focus has been on increasing the power level for large-scale exploration applications. However, there has also been a similar push to examine applications of electric propulsion for small spacecraft in the range of 300 kg or less. There have been several recent iodine Hall propulsion system development activities performed by the team of the NASA Glenn Research Center, the NASA Marshall Space Flight Center, and Busek Co. Inc. In particular, the work focused on qualification of the Busek 200-W BHT-200-I and development of the 600-W BHT-600-I systems. This paper discusses the current status of iodine Hall propulsion system developments along with supporting technology development efforts.

  17. Electrical control of the anomalous valley Hall effect in antiferrovalley bilayers

    Science.gov (United States)

    Tong, Wen-Yi; Duan, Chun-Gang

    2017-08-01

    In analogy to all-electric spintronics, all-electric valleytronics, i.e., valley manipulation via electric means, becomes an exciting new frontier as it may bring revolutions in the field of data storage with ultra-high speed and ultra-low power consumption. The existence of the anomalous valley Hall effect in ferrovalley materials demonstrates the possibility of electrical detection for valley polarization. However, in previously proposed valley-polarized monolayers, the anomalous valley Hall effect is controlled by external magnetic fields. Here, through elaborate structural design, we propose the antiferrovally bilayer as an ideal candidate for realizing all-electric valleytronic devices. Using the minimal k.p model, we show that the energy degeneracy between valley indexes in such system can be lifted by electric approaches. Subsequently, the anomalous valley Hall effect strongly depends on the electric field as well. Taking the bilayer VSe2 as an example, all-electric tuning and detecting of anomalous valley Hall effect is confirmed by density-functional theory calculations, indicating that the valley information in such antiferrovalley bilayer can be reversed by an electric field perpendicular to the plane of the system and easily probed through the sign of the Hall voltage.

  18. Use and utility of Web-based residency program information: a survey of residency applicants.

    Science.gov (United States)

    Embi, Peter J; Desai, Sima; Cooney, Thomas G

    2003-01-01

    The Internet has become essential to the residency application process. In recent years, applicants and residency programs have used the Internet-based tools of the National Residency Matching Program (NRMP, the Match) and the Electronic Residency Application Service (ERAS) to process and manage application and Match information. In addition, many residency programs have moved their recruitment information from printed brochures to Web sites. Despite this change, little is known about how applicants use residency program Web sites and what constitutes optimal residency Web site content, information that is critical to developing and maintaining such sites. To study the use and perceived utility of Web-based residency program information by surveying applicants to an internal medicine program. Our sample population was the applicants to the Oregon Health & Science University Internal Medicine Residency Program who were invited for an interview. We solicited participation using the group e-mail feature available through the Electronic Residency Application Service Post-Office application. To minimize the possibility for biased responses, the study was confined to the period between submission of National Residency Matching Program rank-order lists and release of Match results. Applicants could respond using an anonymous Web-based form or by reply to the e-mail solicitation. We tabulated responses, calculated percentages for each, and performed a qualitative analysis of comments. Of the 431 potential participants, 218 responded (51%) during the study period. Ninety-nine percent reported comfort browsing the Web; 52% accessed the Web primarily from home. Sixty-nine percent learned about residency Web sites primarily from residency-specific directories while 19% relied on general directories. Eighty percent found these sites helpful when deciding where to apply, 69% when deciding where to interview, and 36% when deciding how to rank order programs for the Match. Forty

  19. Sub-grid-scale effects on short-wave instability in magnetized hall-MHD plasma

    International Nuclear Information System (INIS)

    Miura, H.; Nakajima, N.

    2010-11-01

    Aiming to clarify effects of short-wave modes on nonlinear evolution/saturation of the ballooning instability in the Large Helical Device, fully three-dimensional simulations of the single-fluid MHD and the Hall MHD equations are carried out. A moderate parallel heat conductivity plays an important role both in the two kinds of simulations. In the single-fluid MHD simulations, the parallel heat conduction effectively suppresses short-wave ballooning modes but it turns out that the suppression is insufficient in comparison to an experimental result. In the Hall MHD simulations, the parallel heat conduction triggers a rapid growth of the parallel flow and enhance nonlinear couplings. A comparison between single-fluid and the Hall MHD simulations reveals that the Hall MHD model does not necessarily improve the saturated pressure profile, and that we may need a further extension of the model. We also find by a comparison between two Hall MHD simulations with different numerical resolutions that sub-grid-scales of the Hall term should be modeled to mimic an inverse energy transfer in the wave number space. (author)

  20. A portable Hall magnetometer probe for characterization of magnetic iron oxide nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Jefferson F.D.F.; Costa, Mateus C.; Louro, Sonia R.W.; Bruno, Antonio C., E-mail: acbruno@puc-rio.br

    2017-03-15

    We have built a portable Hall magnetometer probe, for measuring magnetic properties of iron oxide nanoparticles, that can be used for bulk materials and liquid samples as well. The magnetometer probe consists of four voltage-programmable commercial Hall sensors and a thin acrylic plate for positioning the sensors. In order to operate, it needs to be attached to a pole of an electromagnet and connected to an AD converter and a computer. It acquires a complete magnetization curve in a couple of minutes and has a magnetic moment sensitivity of 3.5×10{sup −7} Am{sup 2}. We tested its performance with magnetic nanoparticles containing an iron oxide core and having coating layers with different sizes. The magnetization results obtained were compared with measurements performed on commercial stand-alone magnetometers, and exhibited errors of about ±0.2 Am{sup 2}/kg (i.e 0.4%) at saturation and below 0.5 Am{sup 2}/kg (i.e. 10%) at remanence. - Highlights: • A low-cost portable Hall magnetometer probe has been built. • The Hall magnetometer probe can be attached to any electromagnet. • The Hall probe was calibrated and successfully compared to industry standard magnetometers. • The Hall probe was able to measure iron oxide nanoparticles with different coatings.

  1. A portable Hall magnetometer probe for characterization of magnetic iron oxide nanoparticles

    International Nuclear Information System (INIS)

    Araujo, Jefferson F.D.F.; Costa, Mateus C.; Louro, Sonia R.W.; Bruno, Antonio C.

    2017-01-01

    We have built a portable Hall magnetometer probe, for measuring magnetic properties of iron oxide nanoparticles, that can be used for bulk materials and liquid samples as well. The magnetometer probe consists of four voltage-programmable commercial Hall sensors and a thin acrylic plate for positioning the sensors. In order to operate, it needs to be attached to a pole of an electromagnet and connected to an AD converter and a computer. It acquires a complete magnetization curve in a couple of minutes and has a magnetic moment sensitivity of 3.5×10 −7 Am 2 . We tested its performance with magnetic nanoparticles containing an iron oxide core and having coating layers with different sizes. The magnetization results obtained were compared with measurements performed on commercial stand-alone magnetometers, and exhibited errors of about ±0.2 Am 2 /kg (i.e 0.4%) at saturation and below 0.5 Am 2 /kg (i.e. 10%) at remanence. - Highlights: • A low-cost portable Hall magnetometer probe has been built. • The Hall magnetometer probe can be attached to any electromagnet. • The Hall probe was calibrated and successfully compared to industry standard magnetometers. • The Hall probe was able to measure iron oxide nanoparticles with different coatings.

  2. Hallé SHINE on Manchester: Evaluation Report and Executive Summary

    Science.gov (United States)

    Menzies, Victoria; Kasim, Adetayo; Kokotsaki, Dimitra; Hewitt, Catherine; Akhter, Nasima; Collyer, Clare; Younger, Kirsty; Wiggins, Andy; Torgerson, Carole

    2016-01-01

    The "Hallé SHINE on Manchester" (HSoM) programme is a Saturday school educational programme designed to increase the reading and maths attainment, as well as engagement with school, of underachieving and disadvantaged pupils at Key Stage 2. Developed in collaboration between the SHINE Trust and Hallé Orchestra, the intervention provides…

  3. Teacher in Residence: Bringing Science to Students

    CERN Multimedia

    Daisy Yuhas

    CERN welcomes its first Teacher in Residence, Terrence Baine of the University of Oslo. Baine, who originally hails from Canada, will be concurrently completing his PhD in Physics Education during his time at CERN. Like CERN’s High School Teacher Programme (HST), of which Baine is an alumnus, the Teacher in Residence position is designed to help educators spread the science of CERN in a form that is accessible to students and can encourage them to pursue physics throughout their education.   Terrence Baine, first 'teacher in residence' at CERN Baine explains, “It’s very important to have a teacher present who can be that middle person between the young peoplecoming here, whom we are trying to enlighten, and the physicists who work at CERN. The Teacher in Residence can act as an on-site educational consultant.” As Teacher in Residence, Baine’s primary project will be to develop teaching modules, or a series of lesson plans, that can help high schoo...

  4. Josephson tunneling in bilayer quantum Hall system

    International Nuclear Information System (INIS)

    Ezawa, Z.F.; Tsitsishvili, G.; Sawada, A.

    2012-01-01

    A Bose–Einstein condensation is formed by composite bosons in the quantum Hall state. A composite boson carries the fundamental charge (−e). We investigate Josephson tunneling of such charges in the bilayer quantum Hall system at the total filling ν=1. We show the existence of the critical current for the tunneling current to be coherent and dissipationless. Our results explain recent experiments due to [L. Tiemann, Y. Yoon, W. Dietsche, K. von Klitzing, W. Wegscheider, Phys. Rev. B 80 (2009) 165120] and due to [Y. Yoon, L. Tiemann, S. Schmult, W. Dietsche, K. von Klitzing, Phys. Rev. Lett. 104 (2010) 116802]. We predict also how the critical current changes as the sample is tilted in the magnetic field. -- Highlights: ► Composite bosons undergo Bose–Einstein condensation to form the bilayer quantum Hall state. ► A composite boson is a single electron bound to a flux quantum and carries one unit charge. ► Quantum coherence develops due to the condensation. ► Quantum coherence drives the supercurrent in each layer and the tunneling current. ► There exists the critical input current so that the tunneling current is coherent and dissipationless.

  5. Evaluation of ethics education in obstetrics and gynecology residency programs.

    Science.gov (United States)

    Byrne, John; Straub, Heather; DiGiovanni, Laura; Chor, Julie

    2015-03-01

    The objective of the study was to assess the current status of ethics education in obstetrics-gynecology residency programs. A cross-sectional, web-based survey was designed in conjunction with a professional survey laboratory at the University of Chicago. The survey was piloted with a convenience sample of clinical medical ethics fellows to assess question content and clarity. The survey was deployed by e-mail to all obstetrics-gynecology residency program directors. Descriptive statistics were used to analyze participant responses. The University of Chicago's Institutional Review Board deemed this study exempt from institutional review board formal review. Of 242 eligible obstetrics-gynecology residency program directors, 118 (49%) completed the survey. Most respondents were from university-based programs (n = 78, 66%) that were not religiously affiliated (n = 98, 83%) and trained 4-6 residents per postgraduate year (n = 64, 70%). Although 50% of program directors (n = 60) reported having ethics as part of their core curriculum, most programs teach ethics in an unstructured manner. Fifty-seven percent of respondents (n = 66) stated their program dedicated 5 or fewer hours per year to ethics. The majority of program directors (n = 80, 73%) responded they would like more to a lot more ethics education and believed that ethics education should be required (n = 93, 85%) for residents to complete their training. Respondents identified that crowding in the curriculum was a significant barrier to increased ethics training (n = 50, 45%) and two-thirds (n = 74, 67%) reported a lack of faculty expertise as a moderate barrier to providing ethics education in the residency curriculum. This study found that a lack of structured curricula, inadequate faculty expertise, and limited time were important barriers for ethics education in obstetrics-gynecology programs across the nation. Despite these existing challenges, program directors have a strong interest in increasing ethics

  6. Linear waves in a resistive plasma with Hall current

    International Nuclear Information System (INIS)

    Almaguer, J.A.

    1992-01-01

    Dispersion relations for the case of a magnetized plasma are determined taking into account the Hall current and a constant resistivity, η, in Ohm's law. It is found that the Hall effect is relevant only for parallel (to the equilibrium magnetic field) wave numbers in the case of uniform plasmas, giving place to a dispersive behavior. In particular, the cases of η→0 and small (nonzero) resistivity are discussed

  7. Thermoelectric and Hall-effect studies in hydrogenerated nickel foils

    International Nuclear Information System (INIS)

    Rani, R.; Nigam, A.N.

    1978-01-01

    Thermo e.m.f. and Hall constant of hydrogenerated nickel foils have been measured. Termo e.m.f. shows a sign reversal which is not due to the change in sign of the charge carriers, as indicated by the Hall-effect measurements. To account for the sign reversal of thermo e.m.f., it is found necessary to take into account the surface states of chemisorbed hydrogen on nickel

  8. Hall probe for measuring high currents in superconducting coils

    International Nuclear Information System (INIS)

    Ferendeci, A.M.

    1986-01-01

    Constructional details of a compact Hall probe for measuring high currents in superconducting coils are given. The Hall probe is easy to assemble and can be inserted or removed from the system without breaking the superconducting loop. Upper current limit of the probe can be increased by using larger magnetic core material. Shielding becomes necessary if the probe holder is to be placed near large current dependent magnetic fields

  9. Multi-region relaxed Hall magnetohydrodynamics with flow

    Energy Technology Data Exchange (ETDEWEB)

    Lingam, Manasvi, E-mail: mlingam@princeton.edu [Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08544 (United States); Abdelhamid, Hamdi M., E-mail: hamdi@ppl.k.u-tokyo.ac.jp [Graduate School of Frontier Sciences, The University of Tokyo, Kashiwanoha, Kashiwa, Chiba 277-8561 (Japan); Physics Department, Faculty of Science, Mansoura University, Mansoura 35516 (Egypt); Hudson, Stuart R., E-mail: shudson@pppl.gov [Princeton Plasma Physics Laboratory, PO Box 451, Princeton, New Jersey 08543 (United States)

    2016-08-15

    The recent formulations of multi-region relaxed magnetohydrodynamics (MRxMHD) have generalized the famous Woltjer-Taylor states by incorporating a collection of “ideal barriers” that prevent global relaxation and flow. In this paper, we generalize MRxMHD with flow to include Hall effects, and thereby obtain the partially relaxed counterparts of the famous double Beltrami states as a special subset. The physical and mathematical consequences arising from the introduction of the Hall term are also presented. We demonstrate that our results (in the ideal MHD limit) constitute an important subset of ideal MHD equilibria, and we compare our approach against other variational principles proposed for deriving the partially relaxed states.

  10. Deeply virtual Compton scattering in the Hall A of Jefferson laboratory; Diffusion Compton profondement virtuelle dans le Hall A au Jefferson laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Munoz Camacho, C

    2005-12-15

    Generalized Parton Distributions (GPDs), introduced in the late 90's, provide a universal description of hadrons in terms of the underlying degrees of freedom of Quantum Chromodynamics: quarks and gluons. GPDs appear in a wide variety of hard exclusive reactions and the advent of high luminosity accelerator facilities has made the study of GPDs accessible to experiment. Deeply Virtual Compton Scattering (DVCS) is the golden process involving GPDs. The first dedicated DVCS experiment ran in the Hall A of Jefferson Lab in Fall 2004. An electromagnetic calorimeter and a plastic scintillator detector were constructed for this experiment, together with specific electronics and acquisition system. The experiment preparation, data taking and analysis are described in this document. Results on the absolute cross section difference for opposite beam helicities provide the first measurement of a linear combination of GPDs as a function of the momentum transfer to the nucleon. (author)

  11. Medical residents' job satisfaction and their related factors.

    Science.gov (United States)

    Chung, Eun-Kyung; Han, Eui-Ryoung; Woo, Young-Jong

    2013-03-01

    This study was conducted to investigate medical residents' job satisfaction and their related factors to improve the quality of residency program. The study subjects were 159 medical residents being trained at Chonnam National University Hospital, South Korea, in 2011. The participants were asked to complete a short form Minnesota satisfaction questionnaire (MSQ). The mean score for 20 items on the short form MSQ varied between 2.91 and 3.64 on a 5-point Likert scale. The assessment of related factors with job satisfaction revealed that medical residents had higher levels for job satisfaction, particularly those who were women (beta=0.200, p=0.022), and those who had mentorship experience (beta=0.219, p=0.008). This study results indicate that we should expand and support the mentorship program during medical residency to promote job satisfaction.

  12. Mini array of quantum Hall devices based on epitaxial graphene

    International Nuclear Information System (INIS)

    Novikov, S.; Lebedeva, N.; Hämäläinen, J.; Iisakka, I.; Immonen, P.; Manninen, A. J.; Satrapinski, A.

    2016-01-01

    Series connection of four quantum Hall effect (QHE) devices based on epitaxial graphene films was studied for realization of a quantum resistance standard with an up-scaled value. The tested devices showed quantum Hall plateaux R H,2 at a filling factor v = 2 starting from a relatively low magnetic field (between 4 T and 5 T) when the temperature was 1.5 K. The precision measurements of quantized Hall resistance of four QHE devices connected by triple series connections and external bonding wires were done at B = 7 T and T = 1.5 K using a commercial precision resistance bridge with 50 μA current through the QHE device. The results showed that the deviation of the quantized Hall resistance of the series connection of four graphene-based QHE devices from the expected value of 4×R H,2  = 2 h/e 2 was smaller than the relative standard uncertainty of the measurement (<1 × 10 −7 ) limited by the used resistance bridge.

  13. New Fellows and Honorary Fellow

    Indian Academy of Sciences (India)

    ... December 1923. Address: Department of Physics, Joseph Henry Laboratories, Princeton University, Jadwin Hall, Post Box 708, Princeton, NJ 08544-0708, U.S.A.. Contact: Office: (+1-609) 258 5850. Residence: (+1-609) 454 5075. Fax: (+1-609) 258 1006. Email: pwa@princeton.edu. YouTube · Twitter · Facebook · Blog ...

  14. Music hall Markneukirchen; Musikhalle in Markneukirchen

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1996-01-01

    The article presents the new building of the music hall Markneukirchen. From the planned use of the building result very high demands on the ventilation system in order to keep to a sound power level of less than 30 dB(A) in the hall. The building services are dealt with using numerous flowsheets and diagrams: Heat supply, ventilation system, sanitary system, building management, instrumentation and control, electric and lighting systems. (BWI) [Deutsch] Der vorliegende Beitrag stellt den Neubau der Musikhalle Markneukirchen vor. Durch das Nutzungskonzept ergeben sich fuer die Einhaltung eines Schalleistungspegels von weniger als 30 dB(A) im Saalbereich an die Lueftungsanlage sehr hohe Ansprueche. Es werden die raumlufttechnischen Anlagen anhand zahlreicher Flussbilder und Abbildungen vorgestellt: Waermeversorgung, Lueftungstechnik, Sanitaertechnik, Gebaeudeleit- und MSR-Technik, Elektro- und Lichttechnik. (BWI)

  15. Motherhood during residency training: challenges and strategies.

    Science.gov (United States)

    Walsh, Allyn; Gold, Michelle; Jensen, Phyllis; Jedrzkiewicz, Michelle

    2005-07-01

    To determine what factors enable or impede women in a Canadian family medicine residency program from combining motherhood with residency training. To determine how policies can support these women, given that in recent decades the number of female family medicine residents has increased. Qualitative study using in-person interviews. McMaster University Family Medicine Residency Program. Twenty-one of 27 family medicine residents taking maternity leave between 1994 and 1999. Semistructured interviews. The research team reviewed transcripts of audiotaped interviews for emerging themes; consensus was reached on content and meaning. NVIVO software was used for data analysis. Long hours, unpredictable work demands, guilt because absences from work increase workload for colleagues, and residents' high expectations of themselves cause pregnant residents severe stress. This stress continues upon return to work; finding adequate child care is an added stress. Residents report receiving less support from colleagues and supervisors upon return to work; they associate this with no longer being visibly pregnant. Physically demanding training rotations put additional strain on pregnant residents and those newly returned to work. Flexibility in scheduling rotations can help accommodate needs at home. Providing breaks, privacy, and refrigerators at work can help maintain breastfeeding. Allowing residents to remain involved in academic and clinical work during maternity leave helps maintain clinical skills, build new knowledge, and promote peer support. Pregnancy during residency training is common and becoming more common. Training programs can successfully enhance the experience of motherhood during residency by providing flexibility at work to facilitate a healthy balance among the competing demands of family, work, and student life.

  16. Pregnancy among residents enrolled in general surgery (PREGS): a survey of residents in a single Canadian training program.

    Science.gov (United States)

    Merchant, Shaila; Hameed, Morad; Melck, Adrienne

    2011-12-01

    Interest in general surgery has declined, and lack of adequate accommodation for pregnancy and parenting may be a deterrent. We explored resident experiences with these issues within a single general surgery program. We surveyed residents enrolled in the University of British Columbia general surgery program from 1997 to 2009 using a Web-based survey tool. Information regarding demographics, pregnancy, postpartum issues and issues pertaining to maternity/parenting policies was obtained. We used the Student t test, Z test and Fisher exact test for statistical comparisons. Of the 81 residents surveyed, 53 responded (65% response rate). There were fewer pregnancies during residency among female residents than among partners of male residents (PMRs; 9 pregnancies for 6 of 25 residents v. 23 pregnancies for 15 of 28 PMRs, p = 0.002). One of 9 pregnancies among female residents and 5 of 23 among PMRs ended in miscarriage (p > 0.99). Female residents and PMRs reported pregnancy-related complications with equal frequency. All female residents breastfed for at least 6 months; however, 67% (4 of 6) felt their resident role prevented them from breastfeeding as long as they would have liked. Most (5 of 6, 83%) pursued a graduate degree or research during their "maternity leave." More than 50% of residents reported that their own workload increased because of a colleague's pregnancy. Many (36 of 53, 68%) were unaware of the existence of any maternity/parenting policy, and most were in favour of instituting such a policy. Resident mothers do not breastfeed for the desired duration, and precluding factors must be explored. Contingency plans are needed so colleagues are not overburdened when pregnant residents cannot perform clinical duties. General surgery programs must have a formal policy addressing these issues.

  17. Hall Thruster Thermal Modeling and Test Data Correlation

    Science.gov (United States)

    Myers, James; Kamhawi, Hani; Yim, John; Clayman, Lauren

    2016-01-01

    The life of Hall Effect thrusters are primarily limited by plasma erosion and thermal related failures. NASA Glenn Research Center (GRC) in cooperation with the Jet Propulsion Laboratory (JPL) have recently completed development of a Hall thruster with specific emphasis to mitigate these limitations. Extending the operational life of Hall thursters makes them more suitable for some of NASA's longer duration interplanetary missions. This paper documents the thermal model development, refinement and correlation of results with thruster test data. Correlation was achieved by minimizing uncertainties in model input and recognizing the relevant parameters for effective model tuning. Throughout the thruster design phase the model was used to evaluate design options and systematically reduce component temperatures. Hall thrusters are inherently complex assemblies of high temperature components relying on internal conduction and external radiation for heat dispersion and rejection. System solutions are necessary in most cases to fully assess the benefits and/or consequences of any potential design change. Thermal model correlation is critical since thruster operational parameters can push some components/materials beyond their temperature limits. This thruster incorporates a state-of-the-art magnetic shielding system to reduce plasma erosion and to a lesser extend power/heat deposition. Additionally a comprehensive thermal design strategy was employed to reduce temperatures of critical thruster components (primarily the magnet coils and the discharge channel). Long term wear testing is currently underway to assess the effectiveness of these systems and consequently thruster longevity.

  18. 2D massless QED Hall half-integer conductivity and graphene

    International Nuclear Information System (INIS)

    Martínez, A Pérez; Querts, E Rodriguez; Rojas, H Pérez; Gaitan, R; Rodriguez-Romo, S

    2011-01-01

    Starting from the photon self-energy tensor in a magnetized medium, the 3D complete antisymmetric form of the conductivity tensor is found in the static limit of a fermion system C-non-invariant under fermion–antifermion exchange. The massless relativistic 2D fermion limit in QED is derived by using the compactification along the dimension parallel to the magnetic field. In the static limit and at zero temperature, the main features of the quantum Hall effect (QHE) are obtained: the half-integer QHE and the minimum value proportional to e 2 /h for the Hall conductivity. For typical values of graphene the plateaus of the Hall conductivity are also reproduced. (paper)

  19. Crossover between spin swapping and Hall effect in disordered systems

    KAUST Repository

    Saidaoui, Hamed Ben Mohamed

    2015-07-16

    We theoretically study the crossover between spin Hall effect and spin swapping, a recently predicted phenomenon that consists of the interchange between the current flow and its spin polarization directions [M. B. Lifshits and M. I. Dyakonov, Phys. Rev. Lett. 103, 186601 (2009)]. Using a tight-binding model with spin-orbit coupled disorder, spin Hall effect, spin relaxation, and spin swapping are treated on equal footing. We demonstrate that spin swapping and spin Hall effect present very different dependencies as a function of the spin-orbit coupling and disorder strengths and confirm that the former exceeds the latter in the parameter range considered. Three setups are proposed for the experimental observation of the spin swapping effect.

  20. Diaphragm Effect of Steel Space Roof Systems in Hall Structures

    Directory of Open Access Journals (Sweden)

    Mehmet FENKLİ

    2015-09-01

    Full Text Available Hall structures have been used widely for different purposes. They have are reinforced concrete frames and shear wall with steel space roof systems. Earthquake response of hall structures is different from building type structures. One of the most critical nodes is diaphragm effect of steel space roof on earthquake response of hall structures. Diaphragm effect is depending on lateral stiffness capacity of steel space roof system. Lateral stiffness of steel space roof system is related to modulation geometry, support conditions, selected sections and system geometry. In current paper, three representative models which are commonly used in Turkey were taken in to account for investigation. Results of numerical tests were present comparatively

  1. Crossover between spin swapping and Hall effect in disordered systems

    KAUST Repository

    Saidaoui, Hamed Ben Mohamed; Otani, Y.; Manchon, Aurelien

    2015-01-01

    We theoretically study the crossover between spin Hall effect and spin swapping, a recently predicted phenomenon that consists of the interchange between the current flow and its spin polarization directions [M. B. Lifshits and M. I. Dyakonov, Phys. Rev. Lett. 103, 186601 (2009)]. Using a tight-binding model with spin-orbit coupled disorder, spin Hall effect, spin relaxation, and spin swapping are treated on equal footing. We demonstrate that spin swapping and spin Hall effect present very different dependencies as a function of the spin-orbit coupling and disorder strengths and confirm that the former exceeds the latter in the parameter range considered. Three setups are proposed for the experimental observation of the spin swapping effect.

  2. Exposure in emergency general surgery in a time-based residency ...

    African Journals Online (AJOL)

    Objective: This paper aimed to characterize the resident exposure to acute general surgical conditions during a three-months rotation in a general surgical unit. Setting: The Department of Surgery, University of Nairobi and Kenyatta National Referral and Teaching Hospital in Nairobi. MethodS: Four residents (in their first to ...

  3. Anonymity and Electronics: Adapting Preparation for Radiology Resident Examination.

    Science.gov (United States)

    Chapman, Teresa; Reid, Janet R; O'Conner, Erin E

    2017-06-01

    Diagnostic radiology resident assessment has evolved from a traditional oral examination to computerized testing. Teaching faculty struggle to reconcile the differences between traditional teaching methods and residents' new preferences for computerized testing models generated by new examination styles. We aim to summarize the collective experiences of senior residents at three different teaching hospitals who participated in case review sessions using a computer-based, interactive, anonymous teaching tool, rather than the Socratic method. Feedback was collected from radiology residents following participation in a senior resident case review session using Nearpod, which allows residents to anonymously respond to the teaching material. Subjective resident feedback was uniformly enthusiastic. Ninety percent of residents favor a case-based board review incorporating multiple-choice questions, and 94% favor an anonymous response system. Nearpod allows for inclusion of multiple-choice questions while also providing direct feedback to the teaching faculty, helping to direct the instruction and clarify residents' gaps in knowledge before the Core Examination. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  4. Voltage transients in thin-film InSb Hall sensor

    Directory of Open Access Journals (Sweden)

    Alexey Bardin

    Full Text Available The work is reached to study temperature transients in thin-film Hall sensors. We experimentally study InSb thin-film Hall sensor. We find transients of voltage with amplitude about 10 μV on the sensor ports after current switching. We demonstrate by direct measurements that the transients is caused by thermo-e.m.f., and both non-stationarity and heterogeneity of temperature in the film. We find significant asymmetry of temperature field for different direction of the current, which is probably related to Peltier effect. The result can be useful for wide range of scientist who works with switching of high density currents in any thin semiconductor films. 2000 MSC: 41A05, 41A10, 65D05, 65D17, Keywords: Thin-films, Semiconductors, Hall sensor, InSb, thermo-e.m.f.

  5. Complex scattering dynamics and the quantum Hall effects

    International Nuclear Information System (INIS)

    Trugman, S.A.

    1994-01-01

    We review both classical and quantum potential scattering in two dimensions in a magnetic field, with applications to the quantum Hall effect. Classical scattering is complex, due to the approach of scattering states to an infinite number of dynamically bound states. Quantum scattering follows the classical behavior rather closely, exhibiting sharp resonances in place of the classical bound states. Extended scatterers provide a quantitative explanation for the breakdown of the QHE at a comparatively small Hall voltage as seen by Kawaji et al., and possibly for noise effects

  6. Spin Hall magnetoresistance in antiferromagnet/normal metal bilayers

    KAUST Repository

    Manchon, Aurelien

    2017-01-01

    We investigate the emergence of spin Hall magnetoresistance in a magnetic bilayer composed of a normal metal adjacent to an antiferromagnet. Based on a recently derived drift diffusion equation, we show that the resistance of the bilayer depends on the relative angle between the direction transverse to the current flow and the Néel order parameter. While this effect presents striking similarities with the spin Hall magnetoresistance recently reported in ferromagnetic bilayers, its physical origin is attributed to the anisotropic spin relaxation of itinerant spins in the antiferromagnet.

  7. Attitudes toward the use of gender-inclusive language among residency trainees. The McMaster Residency Training Program Directors.

    Science.gov (United States)

    Guyatt, G H; Cook, D J; Griffith, L; Walter, S D; Risdon, C; Liutkus, J

    1997-05-01

    To explore postgraduate medical trainees' attitudes toward the use of gender-inclusive language. Self-administered questionnaire. Seven residency training programs at McMaster University, Hamilton, Ont., from July 1993 to June 1994. Of 225 residents in the programs, 186 responded to the survey, for a response rate of 82.7%. Men and women were equally represented among the respondents. Categorization of attitudes about the use of language as gender-inclusive or gender-exclusive; characteristics predicting a gender-inclusive attitude. Factor analysis and Cronbach's alpha (0.90) supported the existence of a construct related to attitudes about language use, the poles of which were categorized as gender-inclusive and gender-exclusive. The authors classified residents with respect to their attitudes to language use from their responses to the questionnaire. In univariate analyses, sex, residency program and country of graduation significantly predicted a gender-inclusive attitude (p inclusive attitudes, whereas residents in surgery and anesthesia had the most gender-exclusive attitudes. Residents' values are reflected in the language they choose to use. Language use may provide an index of underlying attitudes that may create hostile environments for female trainees.

  8. Canadian pharmacy practice residents' projects: publication rates and study characteristics.

    Science.gov (United States)

    Hung, Michelle; Duffett, Mark

    2013-03-01

    Research projects are a key component of pharmacy residents' education. Projects represent both a large investment of effort for each resident (up to 10 weeks over the residency year) and a large body of research (given that there are currently over 150 residency positions in Canada annually). Publication of results is a vital part of the dissemination of information gleaned from these projects. To determine the publication rate for research projects performed under the auspices of accredited English-language hospital pharmacy residency programs in Canada and to describe the study characteristics of residency projects performed in Ontario from 1999/2000 to 2008/2009. Lists of residents and project titles for the period of interest were obtained from residency coordinators. PubMed, CINAHL, the Canadian Journal of Hospital Pharmacy, and Google were searched for evidence of publication of each project identified, as an abstract or presentation at a meeting, a letter to the editor, or a full-text manuscript. The library holdings of the University of Toronto were reviewed to determine study characteristics of the Ontario residency projects. For the objective of this study relating to publication rate, 518 projects were included. The overall publication rate was 32.2% (60 [35.9%] as abstracts and 107 [64.1%] as full-text manuscripts). Publication in pharmacy-specific journals (66 [61.7%] of 107 full-text manuscripts) was more frequent than publication in non-pharmacy-specific journals. The publication rate of projects as full-text manuscripts remained stable over time. Of the 202 Ontario residency projects archived in the University of Toronto's library, most were cohort studies (83 [41.1%]), and the most common topic was efficacy and/or safety of a medication (46 [22.8%]). Most hospital pharmacy residents' projects were unpublished, and the publication rate of projects as full-text manuscripts has not increased over time. Most projects were observational studies

  9. Spin Hall effect by surface roughness

    KAUST Repository

    Zhou, Lingjun; Grigoryan, Vahram L.; Maekawa, Sadamichi; Wang, Xuhui; Xiao, Jiang

    2015-01-01

    induced by surface roughness subscribes only to the side-jump contribution but not the skew scattering. The paradigm proposed in this paper provides the second, not if only, alternative to generate a sizable spin Hall effect.

  10. On electrostatic acceleration of plasmas with the Hall effect using electrode shaping

    International Nuclear Information System (INIS)

    Wang, Zhehui; Barnes, Cris W.

    2001-01-01

    Resistive magnetohydrodynamics (MHD) is used to model the electromagnetic acceleration of plasmas in coaxial channels. When the Hall effect is considered, the inclusion of resistivity is necessary to obtain physically meaningful solutions. In resistive MHD with the Hall effect, if and only if the electric current and the plasma flow are orthogonal (J·U=0), then there is a conserved quantity, in the form of U 2 /2+w+eΦ/M, along the flow, where U is the flow velocity, Φ is the electric potential, w is the enthalpy, and M is the ion mass. New solutions suggest that in coaxial geometry the Hall effect along the axial plasma flow can be balanced by proper shaping of conducting electrodes, with acceleration then caused by an electrostatic potential drop along the streamlines of the flow. The Hall effect separation of ion and electron flow then just cancels the electrostatic charge separation. Assuming particle ionization increases with energy density in the system, the resulting particle flow rates (J p ) scales with accelerator bias (V bias ) as J p ∝V bias 2 , exceeding the Child--Langmuir limit. The magnitude of the Hall effect (as determined by the Morozov Hall parameter, Ξ, which is defined as the ratio of electric current to particle current) is related to the energy needed for the creation of each ion--electron pair

  11. Analysis of PGY-1 Pharmacy Resident Candidate Letters of Recommendation at an Academically Affiliated Residency Program.

    Science.gov (United States)

    McLaughlin, Milena M; Masic, Dalila; Gettig, Jacob P

    2018-04-01

    Letters of recommendation (LORs) are a critical component for differentiating among similarly qualified pharmacy residency candidates. These letters contain information that is difficult to ascertain from curricula vitae and pharmacy school transcripts. LOR writers may use any words or phrases appropriate for each candidate as there is no set framework for LORs. The objective of this study was to characterize descriptive themes in postgraduate year 1 (PGY-1) pharmacy residency candidates' LORs and to examine which themes of PGY-1 pharmacy residency candidates' LORs are predictive of an interview invitation at an academically affiliated residency program. LORs for candidates from the Pharmacy Online Residency Centralized Application System (PhORCAS) from 2013 and 2014 for the Midwestern University PGY-1 Pharmacy Residency were analyzed. LOR characteristics and descriptive themes were collected. All scores for candidate characteristics and overall PhORCAS recommendation were also recorded. A total of 351 LORs for 111 candidates from 2013 (n = 47 candidates) and 2014 (n = 64 candidates) were analyzed; 36 (32.4%) total candidates were offered an interview. Themes that were identified as predictors of an interview included a higher median (interquartile range) number of standout words (3 words [1.3-4] vs 3.8 words [2.5-5.5], P < .01) and teaching references (3.7 words [2.7-6] vs 5.7 words [3.7-7.8], P = .01). For this residency program, standout words and teaching references were important when offering interviews.

  12. Hall mobility of free charge carriers in highly compensated p-Germanium

    International Nuclear Information System (INIS)

    Gavrilyuk, V.Yi.; Kirnas, Yi.G.; Balakyin, V.D.

    2000-01-01

    Hall mobility of free charge carriers in initial detectors Ge (Ga) is studied. It is established that an increase in the compensation factor results in the enlargement of Hall mobility in germanium highly compensated by introduction of Li ions during their drift in an electrical field

  13. Science, Technology and University in the XIXth Century. The Free-Faculty of Sciences of the University of Salamanca (1875-1902

    Directory of Open Access Journals (Sweden)

    Joaquín PÉREZ MELERO

    2013-11-01

    Full Text Available The Free-Faculty of Sciences of the University of Salamanca was established in 1875 as the only way to continue Science studies in the University. Poorly financed, with little resources and academic acceptance, it survives helped by financial support from the City Hall and the Provincial Deputation, and to the Rector Esperabé5 s will, against the High Education centralization trend which concentres the studies at the Central University of Madrid. That economic and technical poverty provides just only an approach to the physico-chemical sciences in the framework of a provincial University, but helps it to stay alive until its recongnition as «official» faculty in 1902.

  14. Quasi-one-dimensional Hall physics in the Harper–Hofstadter–Mott model

    Science.gov (United States)

    Kozarski, Filip; Hügel, Dario; Pollet, Lode

    2018-04-01

    We study the ground-state phase diagram of the strongly interacting Harper–Hofstadter–Mott model at quarter flux on a quasi-one-dimensional lattice consisting of a single magnetic flux quantum in y-direction. In addition to superfluid phases with various density patterns, the ground-state phase diagram features quasi-one-dimensional analogs of fractional quantum Hall phases at fillings ν = 1/2 and 3/2, where the latter is only found thanks to the hopping anisotropy and the quasi-one-dimensional geometry. At integer fillings—where in the full two-dimensional system the ground-state is expected to be gapless—we observe gapped non-degenerate ground-states: at ν = 1 it shows an odd ‘fermionic’ Hall conductance, while the Hall response at ν = 2 consists of the transverse transport of a single particle–hole pair, resulting in a net zero Hall conductance. The results are obtained by exact diagonalization and in the reciprocal mean-field approximation.

  15. Paired quantum Hall states on noncommutative two-tori

    Energy Technology Data Exchange (ETDEWEB)

    Marotta, Vincenzo [Dipartimento di Scienze Fisiche, Universita di Napoli ' Federico II' and INFN, Sezione di Napoli, Compl. universitario M. Sant' Angelo, Via Cinthia, 80126 Napoli (Italy); Naddeo, Adele, E-mail: naddeo@sa.infn.i [CNISM, Unita di Ricerca di Salerno and Dipartimento di Fisica ' E. R. Caianiello' , Universita degli Studi di Salerno, Via Salvador Allende, 84081 Baronissi (Italy)

    2010-08-01

    By exploiting the notion of Morita equivalence for field theories on noncommutative tori and choosing rational values of the noncommutativity parameter theta (in appropriate units), a one-to-one correspondence between an Abelian noncommutative field theory (NCFT) and a non-Abelian theory of twisted fields on ordinary space can be established. Starting from this general result, we focus on the conformal field theory (CFT) describing a quantum Hall fluid (QHF) at paired states fillings nu=m/(pm+2) Cristofano et al. (2000) , recently obtained by means of m-reduction procedure, and show that it is the Morita equivalent of a NCFT. In this way we extend the construction proposed in Marotta and Naddeo (2008) for the Jain series nu=m/(2pm+1) . The case m=2 is explicitly discussed and the role of noncommutativity in the physics of quantum Hall bilayers is emphasized. Our results represent a step forward the construction of a new effective low energy description of certain condensed matter phenomena and help to clarify the relationship between noncommutativity and quantum Hall fluids.

  16. ADHM and the 4d quantum Hall effect

    Science.gov (United States)

    Barns-Graham, Alec; Dorey, Nick; Lohitsiri, Nakarin; Tong, David; Turner, Carl

    2018-04-01

    Yang-Mills instantons are solitonic particles in d = 4 + 1 dimensional gauge theories. We construct and analyse the quantum Hall states that arise when these particles are restricted to the lowest Landau level. We describe the ground state wavefunctions for both Abelian and non-Abelian quantum Hall states. Although our model is purely bosonic, we show that the excitations of this 4d quantum Hall state are governed by the Nekrasov partition function of a certain five dimensional supersymmetric gauge theory with Chern-Simons term. The partition function can also be interpreted as a variant of the Hilbert series of the instanton moduli space, counting holomorphic sections rather than holomorphic functions. It is known that the Hilbert series of the instanton moduli space can be rewritten using mirror symmetry of 3d gauge theories in terms of Coulomb branch variables. We generalise this approach to include the effect of a five dimensional Chern-Simons term. We demonstrate that the resulting Coulomb branch formula coincides with the corresponding Higgs branch Molien integral which, in turn, reproduces the standard formula for the Nekrasov partition function.

  17. Mission and System Advantages of Iodine Hall Thrusters

    Science.gov (United States)

    Dankanich, John W.; Szabo, James; Pote, Bruce; Oleson, Steve; Kamhawi, Hani

    2014-01-01

    The exploration of alternative propellants for Hall thrusters continues to be of interest to the community. Investments have been made and continue for the maturation of iodine based Hall thrusters. Iodine testing has shown comparable performance to xenon. However, iodine has a higher storage density and resulting higher ?V capability for volume constrained systems. Iodine's vapor pressure is low enough to permit low-pressure storage, but high enough to minimize potential adverse spacecraft-thruster interactions. The low vapor pressure also means that iodine does not condense inside the thruster at ordinary operating temperatures. Iodine is safe, it stores at sub-atmospheric pressure, and can be stored unregulated for years on end; whether on the ground or on orbit. Iodine fills a niche for both low power (10kW) electric propulsion regimes. A range of missions have been evaluated for direct comparison of Iodine and Xenon options. The results show advantages of iodine Hall systems for both small and microsatellite application and for very large exploration class missions.

  18. Stuart Hall and Cultural Studies, circa 1983

    Directory of Open Access Journals (Sweden)

    Ann Curthoys

    2017-11-01

    Full Text Available Stuart Hall sought to internationalise theoretical debates and to create Cultural Studies as interdisciplinary. We chart his theoretical journey through a detailed examination of a series of lectures delivered in 1983 and now published for the first time. In these lectures, he discusses theorists such as E.P. Thompson, Raymond Williams, Louis Althusser, Levi Strauss and Antonio Gramsci, and explores the relationship between ideas and social structure, the specificities of class and race, and the legacies of slavery. We note his turn towards metaphors of divergence and dispersal and highlight how autobiographical and deeply personal Hall is in these lectures, especially in his ego histoire moment of traumatic memory recovery.

  19. Hall magnetohydrodynamics: Conservation laws and Lyapunov stability

    International Nuclear Information System (INIS)

    Holm, D.D.

    1987-01-01

    Hall electric fields produce circulating mass flow in confined ideal-fluid plasmas. The conservation laws, Hamiltonian structure, equilibrium state relations, and Lyapunov stability conditions are presented here for ideal Hall magnetohydrodynamics (HMHD) in two and three dimensions. The approach here is to use the remarkable array of nonlinear conservation laws for HMHD that follow from its Hamiltonian structure in order to construct explicit Lyapunov functionals for the HMHD equilibrium states. In this way, the Lyapunov stability analysis provides classes of HMHD equilibria that are stable and whose linearized initial-value problems are well posed (in the sense of possessing continuous dependence on initial conditions). Several examples are discussed in both two and three dimensions

  20. Coulomb blockade in hierarchical quantum Hall droplets

    International Nuclear Information System (INIS)

    Cappelli, Andrea; Georgiev, Lachezar S; Zemba, Guillermo R

    2009-01-01

    The degeneracy of energy levels in a quantum dot of Hall fluid, leading to conductance peaks, can be readily derived from the partition functions of conformal field theory. Their complete expressions can be found for Hall states with both Abelian and non-Abelian statistics, upon adapting known results for the annulus geometry. We analyze the Abelian states with hierarchical filling fractions, ν = m/(mp ± 1), and find a non-trivial pattern of conductance peaks. In particular, each one of them occurs with a characteristic multiplicity, which is due to the extended symmetry of the m-folded edge. Experimental tests of the multiplicity can shed more light on the dynamics of this composite edge. (fast track communication)

  1. Stuart Hall on Racism and the Importance of Diasporic Thinking

    Science.gov (United States)

    Rizvi, Fazal

    2015-01-01

    In this article, I want to show how my initial encounter with the work of Stuart Hall was grounded in my reading of the later philosophy of Ludwig Wittgenstein, and was shaped by my interest in understanding the nature of racism across the three countries in which I had lived. Over the years, Hall's various writings have helped me to make sense of…

  2. The politics of student housing: Student activism and representation in the determination of the user-price of a public–private partnership residence on a public university campus in South Africa

    Directory of Open Access Journals (Sweden)

    Taabo Mugume

    2015-10-01

    Full Text Available South African universities have been facing a critical shortage in the provision of studenthousing for several years now, and the establishment of public–private partnerships(PPPs is seen as part of the solution to address the shortage (Rensburg, 2011. Thisarticle investigates the effectiveness of the Students’ Representative Council (SRC ofthe University of the Western Cape (UWC in representing student interests during itsnegotiations with university management to reduce the user-price per student for the newKovacs Residence, a PPP student housing complex on the UWC campus. It thus highlightssome of the complexities involved in public–private collaborations on student housingprovision, including the tension between profitability, affordability and equity in the face oforganised student power.The article shows that, considering the various initiatives taken by the SRC to engageuniversity management, and the resulting reduction of the user-price per annum, students’interests were effectively represented by the SRC, even if this view does not correspondwith the perceptions of students. Our analysis uncovers many deficiencies in studentrepresentation processes both within student structures and university management. It issupported by data from in-depth interviews and a focus group discussion. Interviews wereconducted with SRC members and university management, and a focus group discussionwas facilitated with students in residences.

  3. Design and Testing of a Hall Effect Thruster with 3D Printed Channel and Propellant Distributor

    Science.gov (United States)

    Hopping, Ethan P.; Xu, Kunning G.

    2017-01-01

    The UAH-78AM is a low-power Hall effect thruster developed at the University of Alabama in Huntsville with channel walls and a propellant distributor manufactured using 3D printing. The goal of this project is to assess the feasibility of using unconventional materials to produce a low-cost functioning Hall effect thruster and consider how additive manufacturing can expand the design space and provide other benefits. A version of the thruster was tested at NASA Glenn Research Center to obtain performance metrics and to validate the ability of the thruster to produce thrust and sustain a discharge. An overview of the thruster design and transient performance measurements are presented here. Measured thrust ranged from 17.2 millinewtons to 30.4 millinewtons over a discharge power of 280 watts to 520 watts with an anode I (sub SP)(Specific Impulse) range of 870 seconds to 1450 seconds. Temperature limitations of materials used for the channel walls and propellant distributor limit the ability to run the thruster at thermal steady-state.

  4. Thoughts of Quitting General Surgery Residency: Factors in Canada.

    Science.gov (United States)

    Ginther, David Nathan; Dattani, Sheev; Miller, Sarah; Hayes, Paul

    2016-01-01

    Attrition rates in general surgery training are higher than other surgical disciplines. We sought to determine the prevalence with which Canadian general surgery residents consider leaving their training and the contributing factors. An anonymous survey was administered to all general surgery residents in Canada. Responses from residents who considered leaving their training were assessed for importance of contributing factors. The study was conducted at the Royal University Hospital, University of Saskatchewan, Saskatoon, Saskatchewan, Canada, a tertiary academic center. The response rate was approximately 34.0%. A minority (32.0%) reported very seriously or somewhat seriously considering leaving their training, whereas 35.2% casually considered doing so. Poor work-life balance in residency (38.9%) was the single-most important factor, whereas concern about future unemployment (16.7%) and poor future quality of life (15.7%) were next. Enjoyment of work (41.7%) was the most frequent mitigating factor. Harassment and intimidation were reported factors in 16.7%. On analysis, only intention to practice in a nonacademic setting approached significant association with thoughts of leaving (odds ratio = 1.92, CI = 0.99-3.74, p = 0.052). There was no association with sex, program, postgraduate year, relationship status, or subspecialty interest. There was a nonsignificant trend toward more thoughts of leaving with older age. Canadian general surgery residents appear less likely to seriously consider quitting than their American counterparts. Poor work-life balance in residency, fear of future unemployment, and anticipated poor future quality of life are significant contributors to thoughts of quitting. Efforts to educate prospective residents about the reality of the surgical lifestyle, and to assist residents in securing employment, may improve completion rates. Copyright © 2016 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  5. Implementation and Evaluation of a Condom Availability Program on a College Campus: Lessons from the Field

    Science.gov (United States)

    Eastman-Mueller, Heather P.; Gomez-Scott, Jessica R.; Jung, Ae-Kyung; Oswalt, Sara B.; Hagglund, Kristofer

    2016-01-01

    The U.S. Centers for Disease Control and Prevention advocate access to condoms as a critical sexual health prevention strategy. The purpose of this article is to discuss the implementation and evaluation of a condom availability program using dispensing machines in residence halls at a Midwestern U.S. university. Undergraduate students (N = 337)…

  6. Theory of fractional quantum hall effect

    International Nuclear Information System (INIS)

    Kostadinov, I.Z.

    1985-08-01

    A theory of the Fractional Quantum Hall Effect is constructed based on magnetic flux fractionization, which lead to instability of the system against selfcompression. A theorem is proved stating that arbitrary potentials fail to lift a specific degeneracy of the Landau level. For the case of 1/3 fractional filling a model 3-particles interaction is constructed breaking the symmetry. The rigid 3-particles wave function plays the role of order parameter. In a BCS type of theory the gap in the single particles spectrum is produced by the 3-particles interaction. The mean field critical behaviour and critical parameters are determined as well as the Ginsburg-Landau equation coefficients. The Hall conductivity is calculated from the first principles and its temperature dependence is found. The simultaneous tunnelling of 3,5,7 etc. electrons and quantum interference effects are predicted. (author)

  7. ATLAS Assembly Hall Open Day

    CERN Multimedia

    Patrice Loiez

    2004-01-01

    To mark the 50th Anniversary of the founding of CERN, a day of tours, displays and presentations was held in October 2004. The assembly halls for the experiments that were waiting to be installed on the LHC, such as ATLAS shown here, were transformed into display areas and cafés.

  8. Education and training circumstances of radiology for residents in qualified hospitals

    International Nuclear Information System (INIS)

    Imamura, Keiko; Nakajima, Yasuo; Kiba, Ritsuko; Mizunuma, Kimiyoshi; Ida, Masahiro; Kawabuchi, Koichi

    2005-01-01

    This report is a summary of investigations on the title from the aspect of human resources. Data were collected from databases of websites of Residency Electronic Information System, www.reisjp.org, and Foundation for Promotion of Medical training, www.pmet.org.jp, and from Hospital List (February, 2003) where Japanese radiology physicians were actually working. Investigations were performed on: qualification criteria of hospitals for training, their bed number, number of residents to be admitted, number of physicians and supervising doctors, presence/absence of independent radiology department, number of physicians, supervising doctors and expert physicians in the department. The number rate of physicians in the department is identified to be 64.7% and 84.3% of general and university hospitals, respectively; number of residents to be admitted per one supervisor in the university hospitals is 1.5-2.6 times as high as that in general hospitals; and about 1/4 of residents to be admitted may be in circumstances poor for radiology training. (author)

  9. Field theory of anyons and the fractional quantum Hall effect

    International Nuclear Information System (INIS)

    Viefers, S.F.

    1997-11-01

    The thesis is devoted to a theoretical study of anyons, i.e. particles with fractional statistics moving in two space dimensions, and the quantum Hall effect. The latter constitutes the only known experimental realization of anyons in that the quasiparticle excitations in the fractional quantum Hall system are believed to obey fractional statistics. First, the properties of ideal quantum gases in two dimensions and in particular the equation of state of the free anyons gas are discussed. Then, a field theory formulation of anyons in a strong magnetic field is presented and later extended to a system with several species of anyons. The relation of this model to fractional exclusion statistics, i.e. intermediate statistics introduced by a generalization of the Pauli principle, and to the low-energy excitations at the edge of the quantum Hall system is discussed. Finally, the Chern-Simons-Landau-Ginzburg theory of the fractional quantum Hall effect is studied, mainly focusing on edge effects; both the ground state and the low-energy edge excitations are examined in the simple one-component model and in an extended model which includes spin effects

  10. Redesigning journal club in residency

    Directory of Open Access Journals (Sweden)

    Al Achkar M

    2016-05-01

    Full Text Available Morhaf Al Achkar Department of Family Medicine, Indiana University, Indianapolis, IN, USA Abstract: The gap between production and implementation of knowledge is the main reason for the suboptimal quality of health care. To eliminate this gap and improve the quality of patient care, journal club (JC in graduate medical education provides an opportunity for learning the skills of evidence-based medicine. JC, however, continues to face many challenges mainly due to poorly defined goals, inadequate preparation, and lack of interest. This article presents an innovative model to prepare and present JC based on three pillars: dialogical learning through group discussion, mentored residents as peer teachers, and including JC as part of a structured curriculum to learn evidence-based medicine. This engaging model has the potential to transform JC from a moribund session that is daunting for residents into a lively discussion to redefine clinical practice using the most current evidence. Keywords: journal club, residents, peer teaching, evidence-based medicine, dialogical learning

  11. Intravenous fluid prescription practices among pediatric residents in Korea

    OpenAIRE

    Lee, Jiwon M.; Jung, Younghwa; Lee, Se Eun; Lee, Jun Ho; Kim, Kee Hyuck; Koo, Ja Wook; Park, Young Seo; Cheong, Hae Il; Ha, Il-Soo; Choi, Yong; Kang, Hee Gyung

    2013-01-01

    Purpose: Recent studies have established the association between hypotonic fluids administration and hospital-acquired hyponatremia in children, and have contended that hypotonic fluids be removed from routine practice. To assess current intravenous fluid prescription practices among Korean pediatric residents and to call for updated clinical-practice education Methods: A survey-based analysis was carried out. Pediatric residents at six university hospitals in Korea completed a survey consist...

  12. Sensitivity Enhancement of a Vertical-Type CMOS Hall Device for a Magnetic Sensor

    Directory of Open Access Journals (Sweden)

    Sein Oh

    2018-01-01

    Full Text Available This study presents a vertical-type CMOS Hall device with improved sensitivity to detect a 3D magnetic field in various types of sensors or communication devices. To improve sensitivity, trenches are implanted next to the current input terminal, so that the Hall current becomes maximum. The effect of the dimension and location of trenches on sensitivity is simulated in the COMSOL simulator. A vertical-type Hall device with a width of 16 μm and a height of 2 μm is optimized for maximum sensitivity. The simulation result shows that it has a 23% better result than a conventional vertical-type CMOS Hall device without a trench.

  13. Photo-modulation of the spin Hall conductivity of mono-layer transition metal dichalcogenides

    Energy Technology Data Exchange (ETDEWEB)

    Sengupta, Parijat; Bellotti, Enrico [Department of Electrical and Computer Engineering, Boston University, Boston, MA 02215 (United States)

    2016-05-23

    We report on a possible optical tuning of the spin Hall conductivity in mono-layer transition metal dichalcogenides. Light beams of frequencies much higher than the energy scale of the system (the off-resonant condition) do not excite electrons but rearrange the band structure. The rearrangement is quantitatively established using the Floquet formalism. For such a system of mono-layer transition metal dichalcogenides, the spin Hall conductivity (calculated with the Kubo expression in presence of disorder) exhibits a drop at higher frequencies and lower intensities. Finally, we compare the spin Hall conductivity of the higher spin-orbit coupled WSe{sub 2} to MoS{sub 2}; the spin Hall conductivity of WSe{sub 2} was found to be larger.

  14. Overview of Iodine Propellant Hall Thruster Development Activities at NASA Glenn Research Center

    Science.gov (United States)

    Kamhawi, Hani; Benavides, Gabriel; Haag, Thomas; Hickman, Tyler; Smith, Timothy; Williams, George; Myers, James; Polzin, Kurt; Dankanich, John; Byrne, Larry; hide

    2016-01-01

    NASA is continuing to invest in advancing Hall thruster technologies for implementation in commercial and government missions. There have been several recent iodine Hall propulsion system development activities performed by the team of the NASA Glenn Research Center, the NASA Marshall Space Flight Center, and Busek Co. Inc. In particular, the work focused on qualification of the Busek BHT-200-I, 200 W and the continued development of the BHT-600-I Hall thruster propulsion systems. This presentation presents an overview of these development activities and also reports on the results of short duration tests that were performed on the engineering model BHT-200-I and the development model BHT-600-I Hall thrusters.

  15. Hall viscosity of a chiral two-orbital superconductor at finite temperatures

    Science.gov (United States)

    Yazdani-Hamid, Meghdad; Shahzamanian, Mohammad Ali

    2018-06-01

    The Hall viscosity known as the anti-symmetric part of the viscosity fourth-rank tensor. Such dissipationless response which appears for systems with broken time reversal symmetry. We calculate this non-dissipative quantity for a chiral two-orbital superconductor placed in a viscoelastic magnetic field using the linear response theory and apply our calculations to the putative multiband chiral superconductor Sr2RuO4. The chirality origin of a multiband superconductor arises from the interorbital coupling of the superconducting state. This feature leads to the robustness of the Hall viscosity against temperature and impurity effects. We study the temperature effect on the Hall viscosity at the one-loop approximation.

  16. AA under construction in its hall

    CERN Multimedia

    CERN PhotoLab

    1980-01-01

    The Antiproton Accumulator was installed in a specially built hall. Here we see it at an "early" stage of installation, just a few magnets on the floor, no vacuum chamber at all, but: 3 months later there was circulating beam !

  17. Complex dynamics of the integer quantum Hall effect

    International Nuclear Information System (INIS)

    Trugman, S.A.; Nicopoulos, V.N.; Florida Univ., Gainesville, FL

    1991-01-01

    We investigate both classical and quantum potential scattering in two dimensions in a magnetic field, with applications to the integer quantum Hall effect. Classical scattering is complex, due in one case to the approach of scattering states to an infinite number of bound states. We show that bound states are generic, and occur for all but extremely smooth scattering potentials (|rvec ∇| → 0). Quantum scattering follows the classical behavior rather closely, exhibiting sharp resonances rather than classical bound states. Extended scatterers provide an explanation for the breakdown of the QHE at a comparatively small Hall voltage. 16 refs., 14 figs

  18. Theory of the quantized Hall effect. Pt. 3

    International Nuclear Information System (INIS)

    Levine, H.; Pruisken, A.M.M.; Libby, S.B.

    1984-01-01

    In the previous paper, we have demonstrated the need for a phase transition as a function of theta in the non-liner sigma-model describing the quantized Hall effect. In this work, we present arguments for the occurrence of exactly such a transition. We make use of a dilute gas instanton approximation as well as present a more rigorous duality argument to show that the usual scaling of the conductivity to zero at large distances is altered whenever sigmasub(xy)sup((0)) approx.= 1/2ne 2 /h, n integer. This then completes our theory of the quantized Hall effect. (orig.)

  19. Quantum hall fluid on fuzzy two dimensional sphere

    International Nuclear Information System (INIS)

    Luo Xudong; Peng Dantao

    2004-01-01

    After reviewing the Haldane's description about the quantum Hall effect on the fuzzy two-sphere S 2 , authors construct the noncommutative algebra on the fuzzy sphere S 2 and the Moyal structure of the Hilbert space. By constructing noncommutative Chern-Simons theory of the incompressible Hall fluid on the fuzzy sphere and solving the Gaussian constraint with quasiparticle source, authors find the Calogero matrix on S 2 and the complete set of the Laughlin wave function for the lowest Landau level, and this wave function is expressed by the generalized Jack polynomials in terms of spinor coordinates. (author)

  20. SUSTAINED LIVEABILITY: A FRAMEWORK BEYOND ENERGY CONSCIOUS BUILDING CONSERVATION OF MARKET HALLS

    Directory of Open Access Journals (Sweden)

    Neveen Hamza

    2017-11-01

    Full Text Available Market halls are commonly found in  contexts of cultural and heritage value. Positioned in urban centres and transport networks, these unique buildings were originally constructed in the 19th century to ensure better food distribution in growing European cities, then copied to other territories such as Egypt.  We argue that leaving market halls, with their large spanning structures and indoor open space, for dilapidation is a lost opportunity for sustaining community engagement, and educating the public on the original sustainability, neighbourhood regeneration and cultural thinking that underpinned these buildings. The proposed framework extends current sustainable ‘heritage conservation frameworks’ beyond concepts of adding renewable energy technologies, recycling and sustainable goods movement,  to ‘sustaining liveability and social inclusion’. We argue that market halls offer the opportunities to merge the daily activities of buying and selling food with creating local creative economies such as culinary art exhibitions, and culinary schools. The paper consists of two parts: the first discusses the historical urban context of market halls in Cairo; the second proposes a sustainable heritage conservation model for market halls.

  1. Resident wellness: institutional trends over 10 years since 2003

    Directory of Open Access Journals (Sweden)

    Choi D

    2017-07-01

    Full Text Available Dongseok Choi,1,2 Andrea Cedfeldt,3,4 Christine Flores,5 Kimberly Irish,3 Patrick Brunett,3,6 Donald Girard3,4 1OHSU-PSU School of Public Health, Oregon Health & Science University, Portland, OR, USA; 2School of Dentistry, Kyung Hee University, Seoul, Korea; 3Division of Graduate Medical Education, 4Department of Medicine, 5Division of Continuing Professional Development, 6Department of Emergency Medicine, Oregon Health & Science University, Portland, OR, USA Background: The surveys in this study were carried out at the Graduate Medical Education Division at Oregon Health & Science University (OHSU. OHSU implemented two significant wellness initiatives: a wellness program in 2004, and a policy allowing 4 half-days off each academic year to pursue personal or family health care needs in 2010. This study provides a secondary data analysis of five cross-sectional surveys of career satisfaction of resident and fellow trainees. Methods: All trainees were surveyed five times over a 10-year period using anonymous, cross-sectional web-based survey instruments. Surveys included questions about career satisfaction, perceived stress, sleep hours, burnout, and related factors.Results: This represents 10 years of accumulated responses from over 2,200 residents with results showing continual improvement in their career satisfaction. Response rates ranged from 56% to 72%. During the study period, there was a significant positive change in overall resident career satisfaction, with little change in factors traditionally considered to be predictive of overall career satisfaction such as sleep hours or perceived stress level. In addition, our data support that availability of time for personal tasks could positively impact the overall training experience.Conclusion: We postulate that the improvements in satisfaction relate to two major institutional innovations designed to promote resident wellness. Keywords: satisfaction, burnout, graduate medical education

  2. Magnetic properties and Hall effect of single-crystalline YMn6Sn6

    International Nuclear Information System (INIS)

    Uhlirova, K.; Sechovsky, V.; Boer, F.R. de; Yoshii, S.; Yamamoto, T.; Hagiwara, M.; Lefevre, C.; Venturini, G.

    2007-01-01

    Magnetization behavior and Hall resistivity of YMn 6 Sn 6 , which crystallizes in the hexagonal HfFe 6 Ge 6 -type of structure, have been investigated on single crystals at various temperatures in the ordered magnetic state. The field dependence of the Hall resistivity shows anomalies, which are related to the field-induced spin reorientations occurring in YMn 6 Sn 6 . It is also found that the Hall resistivity cannot simply be described by the anomalous contribution proportional to the magnetization, but that an additional field-dependent contribution is present

  3. End-of-Life Care Education for Psychiatric Residents: Attitudes, Preparedness, and Conceptualizations of Dignity

    Science.gov (United States)

    Tait, Glendon R.; Hodges, Brian D.

    2009-01-01

    Objective: The authors examined psychiatric residents' attitudes, perceived preparedness, experiences, and needs in end-of-life care education. They also examined how residents conceptualized good end-of-life care and dignity. Methods: The authors conducted an electronic survey of 116 psychiatric residents at the University of Toronto. The survey…

  4. Valley polarized quantum Hall effect and topological insulator phase transitions in silicene

    KAUST Repository

    Tahir, M.; Schwingenschlö gl, Udo

    2013-01-01

    encountered for graphene, in particular the zero band gap and weak spin orbit interaction. We demonstrate a valley polarized quantum Hall effect and topological insulator phase transitions. We use the Kubo formalism to discuss the Hall conductivity and address

  5. Understanding and Interrupting Hegemonic Projects in Education: Learning from Stuart Hall

    Science.gov (United States)

    Apple, Michael W.

    2015-01-01

    Stuart Hall had a significant impact on critical analyses of rightist mobilizations in education. This is very visible in my own work, for example, in such volumes as "Official Knowledge" (2014) and "Educating the 'Right' Way" (2006). After describing an important series of lectures that Stuart Hall gave at the Havens Center…

  6. Development of a novel sports medicine rotation for emergency medicine residents

    Directory of Open Access Journals (Sweden)

    Waterbrook AL

    2016-04-01

    Full Text Available Anna L Waterbrook,1 T Gail Pritchard,2 Allison D Lane,1 Lisa R Stoneking,1 Bryna Koch,2 Robert McAtee,1 Kristi H Grall,1 Alice A Min,1 Jessica Prior,1 Isaac Farrell,1 Holly G McNulty,1 Uwe Stolz1 1Department of Emergency Medicine, 2Office of Medical Student Education, The University of Arizona, Tucson, AZ, USA Abstract: Musculoskeletal complaints are the most common reason for patients to visit a physician, yet competency in musculoskeletal medicine is invariably reported as a deficiency in medical education in the USA. Sports medicine clinical rotations improve both medical students' and residents' musculoskeletal knowledge. Despite the importance of this knowledge, a standardized sports medicine curriculum in emergency medicine (EM does not exist. Hence, we developed a novel sports medicine rotation for EM residents to improve their musculoskeletal educational experience and to improve their knowledge in musculoskeletal medicine by teaching the evaluation and management of many common musculoskeletal disorders and injuries that are encountered in the emergency department. The University of Arizona has two distinct EM residency programs, South Campus (SC and University Campus (UC. The UC curriculum includes a traditional 4-week orthopedic rotation, which consistently rated poorly on evaluations by residents. Therefore, with the initiation of a new EM residency at SC, we replaced the standard orthopedic rotation with a novel sports medicine rotation for EM interns. This rotation includes attendance at sports medicine clinics with primary care and orthopedic sports medicine physicians, involvement in sport event coverage, assigned reading materials, didactic experiences, and an on-call schedule to assist with reductions in the emergency department. We analyzed postrotation surveys completed by residents, postrotation evaluations of the residents completed by primary care sports medicine faculty and orthopedic chief residents, as well as the

  7. An edge index for the quantum spin-Hall effect

    International Nuclear Information System (INIS)

    Prodan, Emil

    2009-01-01

    Quantum spin-Hall systems are topological insulators displaying dissipationless spin currents flowing at the edges of the samples. In contradistinction to the quantum Hall systems where the charge conductance of the edge modes is quantized, the spin conductance is not and it remained an open problem to find the observable whose edge current is quantized. In this paper, we define a particular observable and the edge current corresponding to this observable. We show that this current is quantized and that the quantization is given by the index of a certain Fredholm operator. This provides a new topological invariant that is shown to take the generic values 0 and 2, in line with the Z 2 topological classification of time-reversal invariant systems. The result gives an effective tool for the investigation of the edge structure in quantum spin-Hall systems. Based on a reasonable assumption, we also show that the edge conducting channels are not destroyed by a random edge. (fast track communication)

  8. Resistivity and Hall voltage in gold thin films deposited on mica at room temperature

    Energy Technology Data Exchange (ETDEWEB)

    Bahamondes, Sebastián; Donoso, Sebastián; Ibañez-Landeta, Antonio; Flores, Marcos [Departamento de Física, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Av. Blanco Encalada 2008, Santiago (Chile); Henriquez, Ricardo, E-mail: ricardo.henriquez@usm.cl [Departamento de Física, Universidad Técnica Federico Santa María, Av. España 1680, Valparaiso 2390123 (Chile)

    2015-03-30

    Highlights: • We determined the 4 K thickness dependence of resistivity for a family of gold thin films. • We determined the thickness dependence of resistivity during the growth process. • Both behaviors are well represented by the Mayadas–Shatzkes theory. • We determined Hall tangent and Hall resistance at 4 K and up to 4.5 T. • Hall mobility is always higher than the drift mobility. - Abstract: We report the thickness dependence of the resistivity measured at 4 K of gold films grown onto mica at room temperature (RT), for thickness ranging from 8 to 100 nm. This dependence was compared to the one obtained for a sample during its growth process at RT. Both behaviors are well represented by the Mayadas–Shatzkes theory. Using this model, we found comparable contributions of electron surface and electron grain boundary scattering to the resistivity at 4 K. Hall effect measurements were performed using a variable transverse magnetic field up to 4.5 T. Hall tangent and Hall resistance exhibit a linear dependence on the magnetic field. For this magnetic field range, the Hall mobility is always larger than the drift mobility. This result is explained through the presence of the above-mentioned scattering mechanisms acting on the galvanomagnetic coefficients. In addition, we report the temperature dependence of the resistivity between 4 and 70 K.

  9. Giant photonic Hall effect in magnetophotonic crystals.

    Science.gov (United States)

    Merzlikin, A M; Vinogradov, A P; Inoue, M; Granovsky, A B

    2005-10-01

    We have considered a simple, square, two-dimensional (2D) PC built of a magneto-optic matrix with square holes. It is shown that using such a magnetophotonic crystal it is possible to deflect a light beam at very large angles by applying a nonzero external magnetic field. The effect is called the giant photonic Hall effect (GPHE) or the magnetic superprism effect. The GPHE is based on magneto-optical properties, as is the photonic Hall effect [B. A. van Tiggelen and G. L. J. A. Rikken, in, edited by V. M. Shalaev (Springer-Verlag, Berlin, 2002), p. 275]; however GPHE is not caused by asymmetrical light scattering but rather by the influence of an external magnetic field on the photonic band structure.

  10. Transformation of a University Lecture Hall in Valladolid (Spain into a NZEB: LCA of a BIPV System Integrated in Its Façade

    Directory of Open Access Journals (Sweden)

    Gloria Y. Palacios-Jaimes

    2017-01-01

    Full Text Available The EU Energy Performance of Buildings Directive (Directive 2010/31/EU poses a major challenge, as it promotes the transformation of existing buildings into nearly zero-energy buildings (NZEB. In this work, we present the case of study of a lecture hall building, owned by the University of Valladolid (Spain, that is currently being refurbished into a NZEB by integration of renewable energy sources (RES, also in line with the requirements from Directive 2009/28/EC. As part of its major renovation, not only Trombe walls and geothermal energy are to be incorporated but also a building-integrated solar photovoltaic (BIPV system to address the electricity needs and reduce the building’s energy use and GHGs in a cost-effective manner. The environmental profile of this BIPV system has been investigated using life cycle impact assessment (LCIA, assessing the net emissions of CO2 and the damages caused in a comparative context with conventional electricity-generation pathways. In spite of the small power installed in this first stage (designed to cover only an annual energy consumption of about 13,000 kWh, around 6% of the total demand, it can be concluded that significant environmental benefits are gained using this system.

  11. The Influence Of Switching-Off The Big Lamps On The Humidity Operation Hall

    International Nuclear Information System (INIS)

    Wiranto, Slamet; Sriawan

    2001-01-01

    When there is no activity in the Operation Hall, the big lamps in this are switched off. Due to the water trap of ventilation system is not in good function, the humidity of the Operation Hall increases. In any point of time the humidity rise over the permitted limit value. To avoid this problem it is needed to investigate the characteristic by measuring the humidity of the Operation Hall at various condition and situation. From the characteristic, it can be determined that for normal condition, the Operation Hall big lamps should be switched off, and 2 days before start-up reactor, the all operation building lamps should be switched on for about 5 days as the operation building humidity back to normal value

  12. Spin Hall effect in a 2DEG in the presence of magnetic couplings

    International Nuclear Information System (INIS)

    Gorini, C; Schwab, P; Dzierzawa, M; Raimondi, R; Milletari, M

    2009-01-01

    It is now well established that the peculiar linear-in-momentum dependence of the Rashba (and of the Dresselhaus) spin-orbit coupling leads to the vanishing of the spin Hall conductivity in the bulk of a two-dimensional electron gas (2DEG). In this paper we discuss how generic magnetic couplings change this behaviour providing then a potential handle on the spin Hall effect. In particular we examine the influence of magnetic impurities and an in-plane magnetic field. We find that in both cases there is a finite spin Hall effect and we provide explicit expressions for the spin Hall conductivity. The results can be obtained by means of the quasiclassical Green function approach, that we have recently extended to spin-orbit coupled electron systems.

  13. Irradiation tests of ITER candidate Hall sensors using two types of neutron spectra

    International Nuclear Information System (INIS)

    Duran, I.; Bolshakova, I.; Holyaka, R.; Viererbl, L.; Lahodova, Z.; Sentkerestiova, J.; Bem, P.

    2010-01-01

    We report on irradiation tests of InSb based Hall sensors at two irradiation facilities with two distinct types of neutron spectra. One was a fission reactor neutron spectrum with a significant presence of thermal neutrons, while another one was purely fast neutron field. Total neutron fluence of the order of 10 16 cm -2 was accumulated in both cases, leading to significant drop of Hall sensor sensitivity in case of fission reactor spectrum, while stable performance was observed at purely fast neutron spectrum. This finding suggests that performance of this particular type of Hall sensors is governed dominantly by transmutation. Additionally, it further stresses the need to test ITER candidate Hall sensors under neutron flux with ITER relevant spectrum.

  14. The STEM Lecture Hall: A Study of Effective Instructional Practices for Diverse Learners

    Science.gov (United States)

    Reimer, Lynn Christine

    First-generation, low-income, underrepresented minority (URM) and female undergraduates are matriculating into science, technology, engineering, and math (STEM) majors at unprecedented levels. However, a disproportionate number of these students end up graduating in non-STEM disciplines. Attrition rates have been observed to spike in conjunction with introductory STEM courses in chemistry, biology, and physics. These "gateway" courses tend to be housed in large, impersonal lecture halls. First-generation and URM students struggle in this environment, possibly because of instructors' reliance on lecture-based content delivery and rote memorization. Recent social psychological studies suggest the problem may be related to cultural mismatch, or misalignment between independent learning norms typical of American universities and interdependent learning expectancies for first-generation and URM students. Value-affirming and utility-value interventions yield impressive academic achievement gains for these students. These findings overlap with a second body of literature on culturally responsive instruction. Active gateway learning practices that emphasize interactive instruction, frequent assessment, and epistemological instruction can be successful because of their propensity to incorporate values affirming and utility-value techniques. The present study observed instruction for gateway STEM courses over a three-year period at the University of California, Irvine (N = 13,856 undergraduates in 168 courses). Exploratory polychoric factor analysis was used to identify latent variables for observational data on gateway STEM instructional practices. Variables were regressed on institutional student data. Practices implemented in large lecture halls fall into three general categories: Faculty-Student Interaction, Epistemological Instruction, and Peer Interaction . The present study found that Faculty-Student Interaction was negatively associated with student outcomes for

  15. Development of a novel sports medicine rotation for emergency medicine residents.

    Science.gov (United States)

    Waterbrook, Anna L; Pritchard, T Gail; Lane, Allison D; Stoneking, Lisa R; Koch, Bryna; McAtee, Robert; Grall, Kristi H; Min, Alice A; Prior, Jessica; Farrell, Isaac; McNulty, Holly G; Stolz, Uwe

    2016-01-01

    Musculoskeletal complaints are the most common reason for patients to visit a physician, yet competency in musculoskeletal medicine is invariably reported as a deficiency in medical education in the USA. Sports medicine clinical rotations improve both medical students' and residents' musculoskeletal knowledge. Despite the importance of this knowledge, a standardized sports medicine curriculum in emergency medicine (EM) does not exist. Hence, we developed a novel sports medicine rotation for EM residents to improve their musculoskeletal educational experience and to improve their knowledge in musculoskeletal medicine by teaching the evaluation and management of many common musculoskeletal disorders and injuries that are encountered in the emergency department. The University of Arizona has two distinct EM residency programs, South Campus (SC) and University Campus (UC). The UC curriculum includes a traditional 4-week orthopedic rotation, which consistently rated poorly on evaluations by residents. Therefore, with the initiation of a new EM residency at SC, we replaced the standard orthopedic rotation with a novel sports medicine rotation for EM interns. This rotation includes attendance at sports medicine clinics with primary care and orthopedic sports medicine physicians, involvement in sport event coverage, assigned reading materials, didactic experiences, and an on-call schedule to assist with reductions in the emergency department. We analyzed postrotation surveys completed by residents, postrotation evaluations of the residents completed by primary care sports medicine faculty and orthopedic chief residents, as well as the total number of dislocation reductions performed by each graduating resident at both programs over the last 5 years. While all residents in both programs exceeded the ten dislocation reductions required for graduation, residents on the sports medicine rotation had a statistically significant higher rate of satisfaction of their educational

  16. Training future surgeons for management roles: the resident-surgeon-manager conference.

    Science.gov (United States)

    Hanna, Waël C; Mulder, David S; Fried, Gerald M; Elhilali, Mostafa; Khwaja, Kosar A

    2012-10-01

    OBJECTIVE To demonstrate that senior surgical residents would benefit from focused training by professionals with management expertise. Although managerial skills are recognized as necessary for the successful establishment of a surgical practice, they are not often emphasized in traditional surgical residency curricula. DESIGN Senior residents from all surgical subspecialties at McGill University were invited to participate in a 1-day management seminar. Precourse questionnaires aimed at evaluating the residents' perceptions of their own managerial knowledge and preparedness were circulated. The seminar was then given in the form of interactive lectures and case-based discussions. The questionnaires were readministered at the end of the course, along with an evaluation form. Precourse and postcourse data were compared using the Freeman-Halton extension of the Fisher exact test to determine statistical significance (P < .05). SETTING McGill University Health Centre in Montreal, Quebec, Canada. PARTICIPANTS A total of 43 senior residents. RESULTS Before the course, the majority of residents (27 of 43 [63%]) thought that management instruction only happened "from time to time" in their respective programs. After the course, 15 residents (35%) felt that management topics were "well addressed," and 19 (44%) felt that management topics have been "very well addressed" (P < .01). Residents noted a significant improvement in their ability to perform the following skills after the course: giving feedback, delegating duties, coping with stress, effective learning, and effective teaching. On the ensemble of all managerial skills combined, 26 residents (60%) rated their performance as "good" or "excellent" after the course vs only 21 (49%) before the course (P = .02). Residents also noted a statistically significant improvement in their ability to perform the managerial duties necessary for the establishment of a surgical practice. CONCLUSIONS Surgical residency programs

  17. Surgical resident learning styles: faculty and resident accuracy at identification of preferences and impact on ABSITE scores.

    Science.gov (United States)

    Kim, Roger H; Gilbert, Timothy; Ristig, Kyle; Chu, Quyen D

    2013-09-01

    As a consequence of surgical resident duty hour restrictions, there is a need for faculty to utilize novel teaching methods to convey information in a more efficient manner. The current paradigm of surgical training, which has not changed significantly since the time of Halsted, assumes that all residents assimilate information in a similar fashion. However, recent data has shown that learners have preferences for the ways in which they receive and process information. The VARK model categorizes learners as visual (V), aural (A), read/write (R), and kinesthetic (K). The VARK learning style preferences of surgical residents have not been previously evaluated. In this study, the preferred learning styles of general surgery residents were determined, along with faculty and resident perception of resident learning styles. In addition, we hypothesized that American Board of Surgery In-Training Exam (ABSITE) scores are associated with preference for a read/write (R) learning style. The Fleming VARK learning styles inventory was administered to all general surgery residents at a university hospital-based program. Responses on the inventory were scored to determine the preferred learning style for each resident. Faculty members were surveyed to determine their accuracy in identifying the preferred learning style of each resident. All residents were also surveyed to determine their accuracy in identifying their peers' VARK preferences. Resident ABSITE scores were examined for association with preferred learning styles. Twenty-nine residents completed the inventory. Most (18 of 29, 62%) had a multimodal preference, although more than a third (11 of 29, 38%) demonstrated a single-modality preference. Seventy-six percent of all residents (22 of 29) had some degree of kinesthetic (K) learning, while under 50% (14 of 29) were aural (A) learners. Although not significant, dominant (R) learners had the highest mean ABSITE scores. Faculty identified residents' learning styles

  18. Optimising Tertiary Student Accommodation within University Neighbourhoods

    OpenAIRE

    Ike, Nnenna; Baldwin, Claudia; Lathouras, Athena

    2017-01-01

    Tertiary students’ activities within neighbourhoods adjacent to universities engender positive and negative impacts that have consequences for neighbourhood sustainability. This might lead to studentification, a process that triggers physical, economic and socio-cultural transformation of university towns. Where non-student residents perceive negative impacts, it can lead to conflict and resentment towards the student population, mistrust between student and local resident groups and a decrea...

  19. General surgery residents' perception of robot-assisted procedures during surgical training.

    Science.gov (United States)

    Farivar, Behzad S; Flannagan, Molly; Leitman, I Michael

    2015-01-01

    With the continued expansion of robotically assisted procedures, general surgery residents continue to receive more exposure to this new technology as part of their training. There are currently no guidelines or standardized training requirements for robot-assisted procedures during general surgical residency. The aim of this study was to assess the effect of this new technology on general surgery training from the residents' perspective. An anonymous, national, web-based survey was conducted on residents enrolled in general surgery training in 2013. The survey was sent to 240 Accreditation Council for Graduate Medical Education-approved general surgery training programs. Overall, 64% of the responding residents were men and had an average age of 29 years. Half of the responses were from postgraduate year 1 (PGY1) and PGY2 residents, and the remainder was from the PGY3 level and above. Overall, 50% of the responses were from university training programs, 32% from university-affiliated programs, and 18% from community-based programs. More than 96% of residents noted the availability of the surgical robot system at their training institution. Overall, 63% of residents indicated that they had participated in robotic surgical cases. Most responded that they had assisted in 10 or fewer robotic cases with the most frequent activities being assisting with robotic trocar placement and docking and undocking the robot. Only 18% reported experience with operating the robotic console. More senior residents (PGY3 and above) were involved in robotic cases compared with junior residents (78% vs 48%, p robotic case. Approximately 64% of residents reported that formal training in robotic surgery was important in residency training and 46% of residents indicated that robotic-assisted cases interfered with resident learning. Only 11% felt that robotic-assisted cases would replace conventional laparoscopic surgery in the future. This study illustrates that although the most residents

  20. Integrated Stirling Convertor and Hall Thruster Test Conducted

    Science.gov (United States)

    Mason, Lee S.

    2002-01-01

    An important aspect of implementing Stirling Radioisotope Generators on future NASA missions is the integration of the generator and controller with potential spacecraft loads. Some recent studies have indicated that the combination of Stirling Radioisotope Generators and electric propulsion devices offer significant trip time and payload fraction benefits for deep space missions. A test was devised to begin to understand the interactions between Stirling generators and electric thrusters. An electrically heated RG- 350 (350-W output) Stirling convertor, designed and built by Stirling Technology Company of Kennewick, Washington, under a NASA Small Business Innovation Research agreement, was coupled to a 300-W SPT-50 Hall-effect thruster built for NASA by the Moscow Aviation Institute (RIAME). The RG-350 and the SPT-50 shown, were installed in adjacent vacuum chamber ports at NASA Glenn Research Center's Electric Propulsion Laboratory, Vacuum Facility 8. The Stirling electrical controller interfaced directly with the Hall thruster power-processing unit, both of which were located outside of the vacuum chamber. The power-processing unit accepted the 48 Vdc output from the Stirling controller and distributed the power to all the loads of the SPT-50, including the magnets, keeper, heater, and discharge. On February 28, 2001, the Glenn test team successfully operated the Hall-effect thruster with the Stirling convertor. This is the world's first known test of a dynamic power source with electric propulsion. The RG-350 successfully managed the transition from the purely resistive load bank within the Stirling controller to the highly capacitive power-processing unit load. At the time of the demonstration, the Stirling convertor was operating at a hot temperature of 530 C and a cold temperature of -6 C. The linear alternator was producing approximately 250 W at 109 Vac, while the power-processing unit was drawing 175 W at 48 Vdc. The majority of power was delivered to the

  1. Mode transition of a Hall thruster discharge plasma

    International Nuclear Information System (INIS)

    Hara, Kentaro; Sekerak, Michael J.; Boyd, Iain D.; Gallimore, Alec D.

    2014-01-01

    A Hall thruster is a cross-field plasma device used for spacecraft propulsion. An important unresolved issue in the development of Hall thrusters concerns the effect of discharge oscillations in the range of 10–30 kHz on their performance. The use of a high speed Langmuir probe system and ultra-fast imaging of the discharge plasma of a Hall thruster suggests that the discharge oscillation mode, often called the breathing mode, is strongly correlated to an axial global ionization mode. Stabilization of the global oscillation mode is achieved as the magnetic field is increased and azimuthally rotating spokes are observed. A hybrid-direct kinetic simulation that takes into account the transport of electronically excited atoms is used to model the discharge plasma of a Hall thruster. The predicted mode transition agrees with experiments in terms of the mean discharge current, the amplitude of discharge current oscillation, and the breathing mode frequency. It is observed that the stabilization of the global oscillation mode is associated with reduced electron transport that suppresses the ionization process inside the channel. As the Joule heating balances the other loss terms including the effects of wall loss and inelastic collisions, the ionization oscillation is damped, and the discharge oscillation stabilizes. A wide range of the stable operation is supported by the formation of a space charge saturated sheath that stabilizes the electron axial drift and balances the Joule heating as the magnetic field increases. Finally, it is indicated from the numerical results that there is a strong correlation between the emitted light intensity and the discharge current.

  2. Disorder effect on chiral edge modes and anomalous Hall conductance in Weyl semimetals

    International Nuclear Information System (INIS)

    Takane, Yositake

    2016-01-01

    Typical Weyl semimetals host chiral surface states and hence show an anomalous Hall response. Although a Weyl semimetal phase is known to be robust against weak disorder, the effect of disorder on chiral states has not been fully clarified so far. We study the behavior of such chiral states in the presence of disorder and its consequences on an anomalous Hall response, focusing on a thin slab of Weyl semimetal with chiral surface states along its edge. It is shown that weak disorder does not disrupt chiral edge states but crucially affects them owing to the renormalization of a mass parameter: the number of chiral edge states changes depending on the strength of disorder. It is also shown that the Hall conductance is quantized when the Fermi level is located near Weyl nodes within a finite-size gap. This quantization of the Hall conductance collapses once the strength of disorder exceeds a critical value, suggesting that it serves as a probe to distinguish a Weyl semimetal phase from a diffusive anomalous Hall metal phase. (author)

  3. The role of the men's hall in the development of the Anglo-Saxon superego.

    Science.gov (United States)

    Earl, J W

    1983-05-01

    This paper is a historical study of ritual space--a bit of psychoanalytic anthropology applied to a particular case, the evolution of the men's hall among the early Anglo-Saxons. I focus particularly on the ritual functions of poetry in the hall, the same poetry which is our major evidence regarding the hall, especially the epic Beowulf. I define the hall as a cultural institution, and redefine the native poetic tradition in relation to the hall's varied ritual life, with which the poetry is so occupied. Though my argument is focused on the hall, it includes a framework of theoretical concerns. Early Anglo-Saxon culture is of anthropological interest chiefly because of its rapid and dramatic emergence from Germanic tribal prehistory into a leading role in the civilization of Christian Europe. The conquest of Britain by the Anglo-Saxons in the fifth and sixth centuries, and their conversion soon afterward, is a case history of the transformations of a tribal society suddenly introduced to the special forces of civilization and the higher religions that control them. The Anglo-Saxons are fascinating in this regard because of the fortuitous developments that prepared for this transformation and made it so successful.

  4. Anomalous Hall conductivity: Local orbitals approach

    Czech Academy of Sciences Publication Activity Database

    Středa, Pavel

    2010-01-01

    Roč. 82, č. 4 (2010), 045115/1-045115/9 ISSN 1098-0121 Institutional research plan: CEZ:AV0Z10100521 Keywords : anomalous Hall effect * Berry phase correction * orbital polarization momentum Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.772, year: 2010

  5. Parametric studies of the Hall Thruster at Soreq

    International Nuclear Information System (INIS)

    Ashkenazy, J.; Rattses, Y.; Appelbaum, G.

    1997-01-01

    An electric propulsion program was initiated at Soreq a few years ago, aiming at the research and development of advanced Hall thrusters for various space applications. The Hall thruster accelerates a plasma jet by an axial electric field and an applied radial magnetic field in an annular ceramic channel. A relatively large current density (> 0.1 A/cm 2 ) can be obtained, since the acceleration mechanism is not limited by space charge effects. Such a device can be used as a small rocket engine onboard spacecraft with the advantage of a large jet velocity compared with conventional rocket engines (10,000-30,000 m/s vs. 2,000-4,800 m/s). An experimental Hall thruster was constructed at Soreq and operated under a broad range of operating conditions and under various configurational variations. Electrical, magnetic and plasma diagnostics, as well as accurate thrust and gas flow rate measurements, have been used to investigate the dependence of thruster behavior on the applied voltage, gas flow rate, magnetic field, channel geometry and wall material. Representative results highlighting the major findings of the studies conducted so far are presented

  6. Dynamical quantum Hall effect in the parameter space.

    Science.gov (United States)

    Gritsev, V; Polkovnikov, A

    2012-04-24

    Geometric phases in quantum mechanics play an extraordinary role in broadening our understanding of fundamental significance of geometry in nature. One of the best known examples is the Berry phase [M.V. Berry (1984), Proc. Royal. Soc. London A, 392:45], which naturally emerges in quantum adiabatic evolution. So far the applicability and measurements of the Berry phase were mostly limited to systems of weakly interacting quasi-particles, where interference experiments are feasible. Here we show how one can go beyond this limitation and observe the Berry curvature, and hence the Berry phase, in generic systems as a nonadiabatic response of physical observables to the rate of change of an external parameter. These results can be interpreted as a dynamical quantum Hall effect in a parameter space. The conventional quantum Hall effect is a particular example of the general relation if one views the electric field as a rate of change of the vector potential. We illustrate our findings by analyzing the response of interacting spin chains to a rotating magnetic field. We observe the quantization of this response, which we term the rotational quantum Hall effect.

  7. Can Future Academic Surgeons be Identified in the Residency Ranking Process?

    Science.gov (United States)

    Beninato, Toni; Kleiman, David A; Zarnegar, Rasa; Fahey, Thomas J

    2016-01-01

    The goal of surgical residency training programs is to train competent surgeons. Academic surgical training programs also have as a mission training future academicians-surgical scientists, teachers, and leaders. However, selection of surgical residents is dependent on a relatively unscientific process. Here we sought to determine how well the residency selection process is able to identify future academicians in surgery. Rank lists from an academic surgical residency program from 1992 to 1997 were examined. All ranked candidates׳ career paths after residency were reviewed to determine whether they stayed in academics, were university affiliated, or in private practice. The study was performed at New York Presbyterian Hospital-Weill Cornell Medical College, New York, NY. A total of 663 applicants for general surgery residency participated in this study. In total 6 rank lists were evaluated, which included 663 candidates. Overall 76% remained in a general surgery subspecialty. Of those who remained in general surgery, 49% were in private practice, 20% were university affiliated, and 31% had academic careers. Approximately 47% of candidates that were ranked in the top 20 had ≥20 publications, with decreasing percentages as rank number increased. There was a strong correlation between the candidates׳ rank position and pursuing an academic career (p career. The residency selection process can identify candidates likely to be future academicians. Copyright © 2016 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  8. Extraordinary Hall effect in Co implanted GaAs hybrid magnetic semiconductors

    International Nuclear Information System (INIS)

    Honda, S.; Tateishi, K.; Nawate, M.; Sakamoto, I.

    2004-01-01

    Hybrid Co/GaAs ferromagnetic semiconductors have been prepared by implantation method. In these samples, sheet resistance shows weak temperature dependence, and the extraordinary Hall effect with positive coefficient is observed. In small Co content samples, Hall resistance increases with decreasing temperature and maximum value of 3.6x10 -2 Ω is obtained at 150 K

  9. Exploring 4D quantum Hall physics with a 2D topological charge pump.

    Science.gov (United States)

    Lohse, Michael; Schweizer, Christian; Price, Hannah M; Zilberberg, Oded; Bloch, Immanuel

    2018-01-03

    The discovery of topological states of matter has greatly improved our understanding of phase transitions in physical systems. Instead of being described by local order parameters, topological phases are described by global topological invariants and are therefore robust against perturbations. A prominent example is the two-dimensional (2D) integer quantum Hall effect: it is characterized by the first Chern number, which manifests in the quantized Hall response that is induced by an external electric field. Generalizing the quantum Hall effect to four-dimensional (4D) systems leads to the appearance of an additional quantized Hall response, but one that is nonlinear and described by a 4D topological invariant-the second Chern number. Here we report the observation of a bulk response with intrinsic 4D topology and demonstrate its quantization by measuring the associated second Chern number. By implementing a 2D topological charge pump using ultracold bosonic atoms in an angled optical superlattice, we realize a dynamical version of the 4D integer quantum Hall effect. Using a small cloud of atoms as a local probe, we fully characterize the nonlinear response of the system via in situ imaging and site-resolved band mapping. Our findings pave the way to experimentally probing higher-dimensional quantum Hall systems, in which additional strongly correlated topological phases, exotic collective excitations and boundary phenomena such as isolated Weyl fermions are predicted.

  10. Exploring 4D quantum Hall physics with a 2D topological charge pump

    Science.gov (United States)

    Lohse, Michael; Schweizer, Christian; Price, Hannah M.; Zilberberg, Oded; Bloch, Immanuel

    2018-01-01

    The discovery of topological states of matter has greatly improved our understanding of phase transitions in physical systems. Instead of being described by local order parameters, topological phases are described by global topological invariants and are therefore robust against perturbations. A prominent example is the two-dimensional (2D) integer quantum Hall effect: it is characterized by the first Chern number, which manifests in the quantized Hall response that is induced by an external electric field. Generalizing the quantum Hall effect to four-dimensional (4D) systems leads to the appearance of an additional quantized Hall response, but one that is nonlinear and described by a 4D topological invariant—the second Chern number. Here we report the observation of a bulk response with intrinsic 4D topology and demonstrate its quantization by measuring the associated second Chern number. By implementing a 2D topological charge pump using ultracold bosonic atoms in an angled optical superlattice, we realize a dynamical version of the 4D integer quantum Hall effect. Using a small cloud of atoms as a local probe, we fully characterize the nonlinear response of the system via in situ imaging and site-resolved band mapping. Our findings pave the way to experimentally probing higher-dimensional quantum Hall systems, in which additional strongly correlated topological phases, exotic collective excitations and boundary phenomena such as isolated Weyl fermions are predicted.

  11. 23rd June 2010 - University of Bristol Head of the Aerospace Engineering Department and Professor of Aerospace Dynamics N. Lieven visiting CERN control centre with Beams Department Head P. Collier, visiting the LHC superconducting magnet test hall with R. Veness and CMS control centre with Collaboration Spokesperson G. Tonelli and CMS User J. Goldstein.

    CERN Multimedia

    Jean-Claude Gadmer

    2010-01-01

    23rd June 2010 - University of Bristol Head of the Aerospace Engineering Department and Professor of Aerospace Dynamics N. Lieven visiting CERN control centre with Beams Department Head P. Collier, visiting the LHC superconducting magnet test hall with R. Veness and CMS control centre with Collaboration Spokesperson G. Tonelli and CMS User J. Goldstein.

  12. Fundamental piezo-Hall coefficients of single crystal p-type 3C-SiC for arbitrary crystallographic orientation

    Science.gov (United States)

    Qamar, Afzaal; Dao, Dzung Viet; Phan, Hoang-Phuong; Dinh, Toan; Dimitrijev, Sima

    2016-08-01

    Piezo-Hall effect in a single crystal p-type 3C-SiC, grown by LPCVD process, has been characterized for various crystallographic orientations. The quantified values of the piezo-Hall effect in heavily doped p-type 3C-SiC(100) and 3C-SiC(111) for different crystallographic orientations were used to obtain the fundamental piezo-Hall coefficients, P 12 = ( 5.3 ± 0.4 ) × 10 - 11 Pa - 1 , P 11 = ( - 2.6 ± 0.6 ) × 10 - 11 Pa - 1 , and P 44 = ( 11.42 ± 0.6 ) × 10 - 11 Pa - 1 . Unlike the piezoresistive effect, the piezo-Hall effect for (100) and (111) planes is found to be independent of the angle of rotation of the device within the crystal plane. The values of fundamental piezo-Hall coefficients obtained in this study can be used to predict the piezo-Hall coefficients in any crystal orientation which is very important for designing of 3C-SiC Hall sensors to minimize the piezo-Hall effect for stable magnetic field sensitivity.

  13. Hall-magnetohydrodynamic waves in flowing ideal incompressible solar-wind plasmas

    International Nuclear Information System (INIS)

    Zhelyazkov, I

    2010-01-01

    It is well established now that the solar atmosphere, from the photosphere to the corona and the solar wind, is a highly structured medium. Satellite observations have confirmed the presence of steady flows there. Here, we investigate the propagation of magnetohydrodynamic (MHD) eigenmodes (kink and sausage surface waves) travelling along an ideal incompressible flowing plasma cylinder (flux tube) surrounded by a flowing plasma environment in the framework of the Hall magnetohydrodynamics. The propagation characteristics of the waves are studied in a reference frame moving with the mass flow outside the tube. In general, the flows change the waves' phase velocities compared with their magnitudes in a static MHD flux tube and the Hall effect extends the number of the possible wave dispersion curves. It turns out that while the kink waves, considered in the context of the standard magnetohydrodynamics, are unstable against the Kelvin-Helmholtz instability, they become stable when the Hall term in the generalized Ohm's law is taken into account. The sausage waves are stable in both considerations. All results concerning the waves' propagation and their stability/instability status are obtained on the basis of the linearized Hall-magnetohydrodynamic equations and are applicable mainly to the solar wind plasmas.

  14. A New Design of a Single-Device 3D Hall Sensor: Cross-Shaped 3D Hall Sensor

    Directory of Open Access Journals (Sweden)

    Wei Tang

    2018-04-01

    Full Text Available In this paper, a new single-device three-dimensional (3D Hall sensor called a cross-shaped 3D Hall device is designed based on the five-contact vertical Hall device. Some of the device parameters are based on 0.18 μm BCDliteTM technology provided by GLOBALFOUNDRIES. Two-dimensional (2D and 3D finite element models implemented in COMSOL are applied to understand the device behavior under a constant magnetic field. Besides this, the influence of the sensing contacts, active region’s depth, and P-type layers are taken into account by analyzing the distribution of the voltage along the top edge and the current density inside the devices. Due to the short-circuiting effect, the sensing contacts lead to degradation in sensitivities. The P-type layers and a deeper active region in turn are responsible for the improvement of sensitivities. To distinguish the P-type layer from the active region which plays the dominant role in reducing the short-circuiting effect, the current-related sensitivity of the top edge (Stop is defined. It is found that the short-circuiting effect fades as the depth of the active region grows. Despite the P-type layers, the behavior changes a little. When the depth of the active region is 7 μm and the thickness of the P-type layers is 3 μm, the sensitivities in the x, y, and z directions can reach 91.70 V/AT, 92.36 V/AT, and 87.10 V/AT, respectively.

  15. Quantum spin/valley Hall effect and topological insulator phase transitions in silicene

    KAUST Repository

    Tahir, M.

    2013-04-26

    We present a theoretical realization of quantum spin and quantum valley Hall effects in silicene. We show that combination of an electric field and intrinsic spin-orbit interaction leads to quantum phase transitions at the charge neutrality point. This phase transition from a two dimensional topological insulator to a trivial insulating state is accompanied by a quenching of the quantum spin Hall effect and the onset of a quantum valley Hall effect, providing a tool to experimentally tune the topological state of silicene. In contrast to graphene and other conventional topological insulators, the proposed effects in silicene are accessible to experiments.

  16. Quantum spin/valley Hall effect and topological insulator phase transitions in silicene

    KAUST Repository

    Tahir, M.; Manchon, Aurelien; Sabeeh, K.; Schwingenschlö gl, Udo

    2013-01-01

    We present a theoretical realization of quantum spin and quantum valley Hall effects in silicene. We show that combination of an electric field and intrinsic spin-orbit interaction leads to quantum phase transitions at the charge neutrality point. This phase transition from a two dimensional topological insulator to a trivial insulating state is accompanied by a quenching of the quantum spin Hall effect and the onset of a quantum valley Hall effect, providing a tool to experimentally tune the topological state of silicene. In contrast to graphene and other conventional topological insulators, the proposed effects in silicene are accessible to experiments.

  17. Can Hall effect trigger Kelvin-Helmholtz instability in sub-Alfvénic flows?

    Science.gov (United States)

    Pandey, B. P.

    2018-05-01

    In the Hall magnetohydrodynamics, the onset condition of the Kelvin-Helmholtz instability is solely determined by the Hall effect and is independent of the nature of shear flows. In addition, the physical mechanism behind the super- and sub-Alfvénic flows becoming unstable is quite different: the high-frequency right circularly polarized whistler becomes unstable in the super-Alfvénic flows whereas low-frequency, left circularly polarized ion-cyclotron wave becomes unstable in the presence of sub-Alfvénic shear flows. The growth rate of the Kelvin-Helmholtz instability in the super-Alfvénic case is higher than the corresponding ideal magnetohydrodynamic rate. In the sub-Alfvénic case, the Hall effect opens up a new, hitherto inaccessible (to the magnetohydrodynamics) channel through which the partially or fully ionized fluid can become Kelvin-Helmholtz unstable. The instability growth rate in this case is smaller than the super-Alfvénic case owing to the smaller free shear energy content of the flow. When the Hall term is somewhat smaller than the advection term in the induction equation, the Hall effect is also responsible for the appearance of a new overstable mode whose growth rate is smaller than the purely growing Kelvin-Helmholtz mode. On the other hand, when the Hall diffusion dominates the advection term, the growth rate of the instability depends only on the Alfvén -Mach number and is independent of the Hall diffusion coefficient. Further, the growth rate in this case linearly increases with the Alfvén frequency with smaller slope for sub-Alfvénic flows.

  18. A system for pulse Hall effect measurements

    International Nuclear Information System (INIS)

    Orzechowski, T.; Kupczak, R.

    1975-01-01

    Measuring system for fast Hall-voltage changes in an n-type germanium sample irradiated at liquid nitrogen temperature with a high-energy electron-beam from the Van de Graaff accelerator is described. (author)

  19. Carl Gustav Jung and Granville Stanley Hall on Religious Experience.

    Science.gov (United States)

    Kim, Chae Young

    2016-08-01

    Granville Stanley Hall (1844-1924) with William James (1842-1910) is the key founder of psychology of religion movement and the first American experimental or genetic psychologist, and Carl Gustav Jung (1875-1961) is the founder of the analytical psychology concerned sympathetically about the religious dimension rooted in the human subject. Their fundamental works are mutually connected. Among other things, both Hall and Jung were deeply interested in how the study of religious experience is indispensable for the depth understanding of human subject. Nevertheless, except for the slight indication, this common interest between them has not yet been examined in academic research paper. So this paper aims to articulate preliminary evidence of affinities focusing on the locus and its function of the inner deep psychic dimension as the religious in the work of Hall and Jung.

  20. Spin Hall effect transistor

    Czech Academy of Sciences Publication Activity Database

    Wunderlich, Joerg; Park, B.G.; Irvine, A.C.; Zarbo, Liviu; Rozkotová, E.; Němec, P.; Novák, Vít; Sinova, Jairo; Jungwirth, Tomáš

    2010-01-01

    Roč. 330, č. 6012 (2010), s. 1801-1804 ISSN 0036-8075 R&D Projects: GA AV ČR KAN400100652; GA MŠk LC510 EU Projects: European Commission(XE) 215368 - SemiSpinNet Grant - others:AV ČR(CZ) AP0801 Program:Akademická prémie - Praemium Academiae Institutional research plan: CEZ:AV0Z10100521 Keywords : spin Hall effect * spintronics * spin transistor Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 31.364, year: 2010