Path integral Monte Carlo simulation of global and local superfluidity in liquidHe4reservoirs separated by nanoscale apertures

Volkoff, Tyler,Kwon, Yongkyung,Whaley, K. Birgitta American Physical Society 2016 Physical Review B Vol.94 No.14

<P>We present a path integral Monte Carlo study of the global superfluid fraction and local superfluid density in cylindrically symmetric reservoirs of liquid He-4 separated by nanoaperture arrays. The superfluid response to both translations along the axis of symmetry (longitudinal response) and rotations about the cylinder axis (transverse response) are computed, together with radial and axial density distributions that reveal the microscopic inhomogeneity arising from the combined effects of the confining external potential and the He-4-He-4 interatomic potentials. We make a microscopic determination of the length scale of decay of superfluidity at the radial boundaries of the system by analyzing the local superfluid density distribution to extract a displacement length that quantifies the superfluid mass displacement away from the boundary. We find that the longitudinal superfluid response is reduced in reservoirs separated by a septum containing sufficiently small apertures compared to a cylinder with no intervening aperture array, for all temperatures below T-lambda. For a single aperture in the septum, a significant drop in the longitudinal superfluid response is seen when the aperture diameter is made smaller than twice the empirical temperature-dependent He-4 healing length, consistent with the formation of a weak link between the reservoirs. Increasing the diameter of a single aperture or the number of apertures in the array results in an increase of the superfluid density toward the expected bulk value.</P>

Local superfluidity in inhomogeneous quantum fluids

Kwon, Yongkyung,Paesani, Francesco,Whaley, K. Birgitta American Physical Society 2006 Physical review. B, Condensed matter and materials Vol.74 No.17

HUMAN ERRORS DURING THE SIMULATIONS OF AN SGTR SCENARIO: APPLICATION OF THE HERA SYSTEM

WONDEA JUNG,APRIL M. WHALEY,BRUCE P. HALLBERT 한국원자력학회 2009 Nuclear Engineering and Technology Vol.41 No.10

Due to the need of data for a Human Reliability Analysis (HRA), a number of data collection efforts have been undertaken in several different organizations. As a part of this effort, a human error analysis that focused on a set of simulator records on a Steam Generator Tube Rupture (SGTR) scenario was performed by using the Human Event Repository and Analysis (HERA) system. This paper summarizes the process and results of the HERA analysis, including discussions about the usability of the HERA system for a human error analysis of simulator data. Five simulated records of an SGTR scenario were analyzed with the HERA analysis process in order to scrutinize the causes and mechanisms of the human related events. From this study, the authors confirmed that the HERA was a serviceable system that can analyze human performance qualitatively from simulator data. It was possible to identify the human related events in the simulator data that affected the system safety not only negatively but also positively. It was also possible to scrutinize the Performance Shaping Factors (PSFs) and the relevant contributory factors with regard to each identified human event.

HUMAN ERRORS DURING THE SIMULATIONS OF AN SGTR SCENARIO: APPLICATION OF THE HERA SYSTEM

Jung, Won-Dea,Whaley, April M.,Hallbert, Bruce P. Korean Nuclear Society 2009 Nuclear Engineering and Technology Vol.41 No.10

Due to the need of data for a Human Reliability Analysis (HRA), a number of data collection efforts have been undertaken in several different organizations. As a part of this effort, a human error analysis that focused on a set of simulator records on a Steam Generator Tube Rupture (SGTR) scenario was performed by using the Human Event Repository and Analysis (HERA) system. This paper summarizes the process and results of the HERA analysis, including discussions about the usability of the HERA system for a human error analysis of simulator data. Five simulated records of an SGTR scenario were analyzed with the HERA analysis process in order to scrutinize the causes and mechanisms of the human related events. From this study, the authors confirmed that the HERA was a serviceable system that can analyze human performance qualitatively from simulator data. It was possible to identify the human related events in the simulator data that affected the system safety not only negatively but also positively. It was also possible to scrutinize the Performance Shaping Factors (PSFs) and the relevant contributory factors with regard to each identified human event.

Influence of Inquiry Frequency on Ratings of Perceived Exertion during Graded Exercise Testing

( Sung Hee Han ),( Mitchell H. Whaley ),( Leonard A. Kaminsky ) 한국스포츠정책과학원(구 한국스포츠개발원) 2001 International Journal of Applied Sports Sciences Vol.13 No.2

Procedures for use of the Borg rating of perceived exertion scale (RPE) during graded exercise testing (GXT) vary from inquiries made once per exercise stage to as frequently as every minute during the test. However, previous studies assessing the reliability of the scale during GXTs suggest that inquiry frequency may influence RPEs at fixed submaximal exercise levels. The purpose of this study was to further examine the effect of inquiry frequency on RPEs during maximal GXT on a treadmill (TM). Fifteen young men and women were randomly assigned to complete two GXTs within 48 hours using the standard Bruce protocol. RPE queries were made either once per stage (RPE-S) or once per minute (RPE-M). Heart rate, oxygen uptake, minute ventilation and respiratory exchange ratio were compared across GXTs at the end of each submaximal stage and peak exercise using repeated-measures ANOVA. No differences were observed between the GXTs for any physiological measures during submaximal or peak exercise. Peak RPEs were not different between the GXTs (19.1 ±0.9 vs. 19.0±0.7). However, RPEs were significantly higher (p<0.01) at each submaximal stage during the RPE-M condition. Oxygen uptakes at Bruce protocol stages I, II and III represented 40, 58 and 81 percent of VO2 peak, respectively, so RPE differences have practical implications at exercise intensities within the typical exercise training range. More frequent RPE inquiries may serve to reinforce an internal attentional focus during the exercise test and thus contribute to the higher RPEs. These data confirm that inquiry frequency can significantly influence submaximal RPE responses during GXTs and therefore, RPE inquiry methods should be standardized when data are collected for serial comparative purposes.

Local food purchasing in the farmers’ market

Christopher Sneed,Ann Fairhurst,Jeremy E. Whaley 한국관광연구학회 2019 관광연구저널 Vol.33 No.4

From local farmers’ markets to local homes, a vast demand exists for local foods. However, the literature on local foods remains undeveloped, especially in the sense of empirically-based research. The study employs value-attitude-behavior theory to examine local food purchases in the farmers’ market context. The study utilizes structural equation modeling via a consumer panel (n = 485) to explore the causal relationships among latent variables related to value, attitude, and behavior in the setting of farmers’ markets. Results indicate that four value constructs (e.g., food novelty, food safety, civic engagement, and environmental concern) influence consumers’ attitudes regarding design, social, and local food quality aspects in the farmers’ market, and eventually influencing behavioral intentions such as purchase intention and word-of-mouth recommendations. Practitioners who focus on the areas of local foods production and consumption must engage with audiences they wish to serve. Practitioners may devise creative marketing strategies to address the needs of their target audience by understanding the relationships among their value, attitude, and behavior.

A MULTIVRIATE ANALYSIS OF OVERALL COMMITMENT TO THE EMPLOYING ORGANIZATION

Huh, Chul-boo,Bahorek, Stanley J.,Larson, Erik W.,Naughtom, Thomas J.,Whaley, Gary L. 明知大學校 經濟硏究所 1985 경영연구 Vol.1 No.1

Although there have been many studies which have explored the relationship between job satisfaction, job related tension, or organizational commitment with various independent variables (Herzberg, et al, 1959; Hulin and Blood, 1968; Vroom, 1964, 1965; Hrebiniak and Alutto, 1973; Buchanon, 1974; Alutto and Hrebiniak, 1975), there has been little effort to consider all three simultaneously.

<i>CYP2D6</i> Genotype and Adjuvant Tamoxifen: Meta-Analysis of Heterogeneous Study Populations

Province, M A,Goetz, M P,Brauch, H,Flockhart, D A,Hebert, J M,Whaley, R,Suman, V J,Schroth, W,Winter, S,Zembutsu, H,Mushiroda, T,Newman, W G,Lee, M-T M,Ambrosone, C B,Beckmann, M W,Choi, J-Y,Dieudonn& C. V. Mosby 2014 Clinical Pharmacology & Therapeutics Vol. No.

<P>The International Tamoxifen Pharmacogenomics Consortium was established to address the controversy regarding cytochrome P450 2D6 (<I>CYP2D6</I>) status and clinical outcomes in tamoxifen therapy. We performed a meta-analysis on data from 4,973 tamoxifen-treated patients (12 globally distributed sites). Using strict eligibility requirements (postmenopausal women with estrogen receptor–positive breast cancer, receiving 20 mg/day tamoxifen for 5 years, criterion 1); CYP2D6 poor metabolizer status was associated with poorer invasive disease–free survival (IDFS: hazard ratio = 1.25; 95% confidence interval = 1.06, 1.47; <I>P</I> = 0.009). However, <I>CYP2D6</I> status was not statistically significant when tamoxifen duration, menopausal status, and annual follow-up were not specified (criterion 2, <I>n</I> = 2,443; <I>P</I> = 0.25) or when no exclusions were applied (criterion 3, <I>n</I> = 4,935; <I>P</I> = 0.38). Although <I>CYP2D6</I> is a strong predictor of IDFS using strict inclusion criteria, because the results are not robust to inclusion criteria (these were not defined <I>a priori</I>), prospective studies are necessary to fully establish the value of <I>CYP2D6</I> genotyping in tamoxifen therapy.</P>

Genome-wide and candidate gene approaches of clopidogrel efficacy using pharmacodynamic and clinical end points—Rationale and design of the International Clopidogrel Pharmacogenomics Consortium (ICPC)

Bergmeijer, Thomas O.,Reny, Jean-Luc,Pakyz, Ruth E.,Gong, Li,Lewis, Joshua P.,Kim, Eun-Young,Aradi, Daniel,Fernandez-Cadenas, Israel,Horenstein, Richard B.,Lee, Ming Ta Michael,Whaley, Ryan M.,Montane Elsevier 2018 American Heart Journal Vol.198 No.-

<P><B>Rationale</B></P> <P>The P2Y<SUB>12</SUB> receptor inhibitor clopidogrel is widely used in patients with acute coronary syndrome, percutaneous coronary intervention, or ischemic stroke. Platelet inhibition by clopidogrel shows wide interpatient variability, and high on-treatment platelet reactivity is a risk factor for atherothrombotic events, particularly in high-risk populations. <I>CYP2C19</I> polymorphism plays an important role in this variability, but heritability estimates suggest that additional genetic variants remain unidentified. The aim of the International Clopidogrel Pharmacogenomics Consortium (ICPC) is to identify genetic determinants of clopidogrel pharmacodynamics and clinical response.</P> <P><B>Study design</B></P> <P>Based on the data published on www.clinicaltrials.gov, clopidogrel intervention studies containing genetic and platelet function data were identified for participation. Lead investigators were invited to share DNA samples, platelet function test results, patient characteristics, and cardiovascular outcomes to perform candidate gene and genome-wide studies.</P> <P><B>Results</B></P> <P>In total, 17 study sites from 13 countries participate in the ICPC, contributing individual patient data from 8,829 patients. Available adenosine diphosphate–stimulated platelet function tests included vasodilator-stimulated phosphoprotein assay, light transmittance aggregometry, and the VerifyNow P2Y<SUB>12</SUB> assay. A proof-of-principle analysis based on genotype data provided by each group showed a strong and consistent association between <I>CYP2C19</I>*2 and platelet reactivity (<I>P</I> value=5.1 × 10<SUP>−40</SUP>).</P> <P><B>Conclusion</B></P> <P>The ICPC aims to identify new loci influencing clopidogrel efficacy by using state-of-the-art genetic approaches in a large cohort of clopidogrel-treated patients to better understand the genetic basis of on-treatment response variability.</P>