WorldWideScience

Sample records for observation attrition rates

  1. How can attrition rates be reduced in cancer drug discovery?

    Science.gov (United States)

    Moreno, Lucas; Pearson, Andrew D J

    2013-04-01

    Attrition is a major issue in anticancer drug development with up to 95% of drugs tested in Phase I trials not reaching a marketing authorisation making the drug development process enormously costly and inefficient. It is essential that this problem is addressed throughout the whole drug development process to improve efficiency which will ultimately result in increased patient benefit with more profitable drugs. The approach to reduce cancer drug attrition rates must be based on three pillars. The first of these is that there is a need for new pre-clinical models which can act as better predictors of success in clinical trials. Furthermore, clinical trials driven by tumour biology with the incorporation of predictive and pharmacodynamic biomarkers would be beneficial in drug development. Finally, there is a need for increased collaboration to combine the unique strengths between industry, academia and regulators to ensure that the needs of all stakeholders are met.

  2. Attrition and success rates of accelerated students in nursing courses: a systematic review.

    Science.gov (United States)

    Doggrell, Sheila Anne; Schaffer, Sally

    2016-01-01

    There is a comprehensive literature on the academic outcomes (attrition and success) of students in traditional/baccalaureate nursing programs, but much less is known about the academic outcomes of students in accelerated nursing programs. The aim of this systematic review is to report on the attrition and success rates (either internal examination or NCLEX-RN) of accelerated students, compared to traditional students. For the systematic review, the databases (Pubmed, Cinahl and PsychINFO) and Google Scholar were searched using the search terms 'accelerated' or 'accreditation for prior learning', 'fast-track' or 'top up' and 'nursing' with 'attrition' or 'retention' or 'withdrawal' or 'success' from 1994 to January 2016. All relevant articles were included, regardless of quality. The findings of 19 studies of attrition rates and/or success rates for accelerated students are reported. For international accelerated students, there were only three studies, which are heterogeneous, and have major limitations. One of three studies has lower attrition rates, and one has shown higher success rates, than traditional students. In contrast, another study has shown high attrition and low success for international accelerated students. For graduate accelerated students, most of the studies are high quality, and showed that they have rates similar or better than traditional students. Thus, five of six studies have shown similar or lower attrition rates. Four of these studies with graduate accelerated students and an additional seven studies of success rates only, have shown similar or better success rates, than traditional students. There are only three studies of non-university graduate accelerated students, and these had weaknesses, but were consistent in reporting higher attrition rates than traditional students. The paucity and weakness of information available makes it unclear as to the attrition and/or success of international accelerated students in nursing programs. The

  3. Attrition and success rates of accelerated students in nursing courses: a systematic review

    OpenAIRE

    Doggrell, Sheila Anne; Schaffer, Sally

    2016-01-01

    Background There is a comprehensive literature on the academic outcomes (attrition and success) of students in traditional/baccalaureate nursing programs, but much less is known about the academic outcomes of students in accelerated nursing programs. The aim of this systematic review is to report on the attrition and success rates (either internal examination or NCLEX-RN) of accelerated students, compared to traditional students. Methods For the systematic review, the databases (Pubmed, Cinah...

  4. A Correlational Study of a Reading Comprehension Program and Attrition Rates of ESL Nursing Students in Texas.

    Science.gov (United States)

    Donnell, Wendy M

    The purpose of this study was to examine the associations between English as a second language (ESL), a reading comprehension program, and attrition rates of nursing students. Higher attrition rates of ESL nursing students are an assumption, seemingly based on anecdotal evidence. Data reflecting ESL student attrition should be measured and analyzed so that students can be identified prior to attrition. A secondary analysis of a large database of 27 initial licensure programs in Texas was completed. Data analysis identified that ESL students who used a reading comprehension program were almost twice as likely to be off track or out of the program as ESL students who did not use the program. Nurse educators need to evaluate student profile characteristics in a comprehensive way when determining risk of attrition.

  5. Are pilot trials useful for predicting randomisation and attrition rates in definitive studies: A review of publicly funded trials

    Science.gov (United States)

    Whitehead, Amy; Pottrill, Edward; Julious, Steven A; Walters, Stephen J

    2018-01-01

    Background/aims: External pilot trials are recommended for testing the feasibility of main or confirmatory trials. However, there is little evidence that progress in external pilot trials actually predicts randomisation and attrition rates in the main trial. To assess the use of external pilot trials in trial design, we compared randomisation and attrition rates in publicly funded randomised controlled trials with rates in their pilots. Methods: Randomised controlled trials for which there was an external pilot trial were identified from reports published between 2004 and 2013 in the Health Technology Assessment Journal. Data were extracted from published papers, protocols and reports. Bland–Altman plots and descriptive statistics were used to investigate the agreement of randomisation and attrition rates between the full and external pilot trials. Results: Of 561 reports, 41 were randomised controlled trials with pilot trials and 16 met criteria for a pilot trial with sufficient data. Mean attrition and randomisation rates were 21.1% and 50.4%, respectively, in the pilot trials and 16.8% and 65.2% in the main. There was minimal bias in the pilot trial when predicting the main trial attrition and randomisation rate. However, the variation was large: the mean difference in the attrition rate between the pilot and main trial was −4.4% with limits of agreement of −37.1% to 28.2%. Limits of agreement for randomisation rates were −47.8% to 77.5%. Conclusion: Results from external pilot trials to estimate randomisation and attrition rates should be used with caution as comparison of the difference in the rates between pilots and their associated full trial demonstrates high variability. We suggest using internal pilot trials wherever appropriate. PMID:29361833

  6. Non-Rated Air Force Line Officer Attrition Rates Using Survival Analysis

    Science.gov (United States)

    2015-03-26

    Further complicating human resourcing, all Air Force members–enlisted and officer–start at entry-level. Personnel entering the Air Force inventory are...the system [8]. Chi-squared automatic interaction detection (CHAID) is an algorithm “to predict the response behaviour [sic] of individuals as...branches with the highest probability may require incentives to increase attrition. The branches could be defined by gender, career field, religion

  7. Attrition Cost Model Instruction Manual

    Science.gov (United States)

    Yanagiura, Takeshi

    2012-01-01

    This instruction manual explains in detail how to use the Attrition Cost Model program, which estimates the cost of student attrition for a state's higher education system. Programmed with SAS, this model allows users to instantly calculate the cost of attrition and the cumulative attrition rate that is based on the most recent retention and…

  8. A review of trends in attrition rates for surgical faculty: a case for a sustainable retention strategy to cope with demographic and economic realities.

    Science.gov (United States)

    Satiani, Bhagwan; Williams, Thomas E; Brod, Heather; Way, David P; Ellison, E Christopher

    2013-05-01

    Our aim was to compare trends in retention of academic surgeons by reviewing surgical faculty attrition rates (leaving academic surgery for any reason) of 3 cohorts at 5-year intervals between 1996 and 2011. The Association of American Medical Colleges' Faculty Administrative Management On-Line User System database was queried for a retention report of all tenure/clinical track full-time MD faculty within our academic medical center on July 1, 1996 (group 1), July 1, 2001 (group 2), and July 1, 2006 (group 3). Retention was tracked for 5 years post snapshot. The individual 5-year cohort attrition rates (observed frequencies) were compared with combined attrition rates for all 3 groups (expected frequencies). Overall, attrition trends for groups 2 (lower) and 3 (higher) were significantly different than the trends for all groups combined. Minorities and professors at the full or associate rank in group 3 contributed to this difference. Faculty in group 3 leaving our academic medical center were significantly more likely to transition into nonacademic practice compared with the other 2 groups. Greater attrition in the last 5-year cohort, despite the increase in faculty positions, is worrisome. A continuous retention life cycle is critical if academic medical centers hope to compete for talent. Retention planning should include on-boarding programs for enculturation, monitoring of professional satisfaction, formalized mentoring of younger surgeons, retaining academic couples and a part-time workforce, leadership and talent management, exit interviews, and competitive financial packages. Copyright © 2013 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

  9. Observed Barium Emission Rates

    Science.gov (United States)

    Stenbaek-Nielsen, H. C.; Wescott, E. M.; Hallinan, T. J.

    1993-01-01

    The barium releases from the CRRES satellite have provided an opportunity for verifying theoretically calculated barium ion and neutral emission rates. Spectra of the five Caribbean releases in the summer of 1991 were taken with a spectrograph on board a U.S. Air Force jet aircraft. Because the line of sight release densities are not known, only relative rates could be obtained. The observed relative rates agree well with the theoretically calculated rates and, together with other observations, confirm the earlier detailed theoretical emission rates. The calculated emission rates can thus with good accuracy be used with photometric observations. It has been postulated that charge exchange between neutral barium and oxygen ions represents a significant source for ionization. If so. it should be associated with emissions at 4957.15 A and 5013.00 A, but these emissions were not detected.

  10. Factors Associated with Veterinary Clinical Faculty Attrition.

    Science.gov (United States)

    Furr, Martin

    Faculty attrition and recruitment for veterinary clinical faculty positions have been reported as significant problems in veterinary medical education. To investigate the factors that may be important in veterinary clinical faculty retention, the perceptions and views of veterinary clinical academic faculty were determined using a web-distributed electronic survey. Responses were dichotomized by whether the respondent had or had not left an academic position and were analyzed for their association with faculty attrition. A total of 1,226 responses were recorded, and results demonstrated that factors other than compensation were associated with veterinary clinical faculty attrition, including departmental culture, work-life balance, and recognition and support of clinical medicine by the administration. Forty-four percent of respondents who had held a faculty appointment reported leaving academia either voluntarily or for non-voluntary reasons such as failure to achieve tenure, retirement, or having their position closed. Attention to correcting deficiencies in workplace culture and professional rewards could be a beneficial means by which to decrease the faculty attrition rates currently observed in clinical academic veterinary medicine.

  11. The Dissertation Story: What Is the Relationship between the Officer Candidate School Attrition Rate and Officer Training Command, Naval Service Training Command and Navy Recruiting Command Leadership Intervention?

    Science.gov (United States)

    2013-03-01

    attrition (Goodstadt, 1981). Kubisiak, et al. contend that leaders should consider attrition a negative occurrence and that each leader should develop...related to the information, and the consequences associated with the options. The ability to ruminate before acting when presented with new information or

  12. Attrition of Tyee Formation Sandstone in a Natural Fluvial System

    Science.gov (United States)

    brandes, J. B.; Sanfilippo, J. D.; Lancaster, S. T.

    2013-12-01

    The data from this study will provide a rate of attrition with respect to change in volume, time and distance in a natural stream setting. Sandstone gravel attrition has been observed in previous studies with the use of rock tumblers, but measurements in natural systems are rare or absent. This study will use rocks with implanted passive integrated transponders (PIT) tags to track sediment movement. The study area is a natural mountain stream of approximately 4m width and 1m depth. This study is part of larger study of sediment transport. The rock volumes will be recorded prior to placement in an active channel using water displacement, the specific location along the channel will be recorded, and each tracer rock will be tracked using its individual radio frequency identification (RFID) number. Tracer rock deployment will occur before the annual high-water season. After one rainy season, the rocks will be located and removed from the stream using a radio frequency mobile radio frequency tracker. Their travel distances will be recorded and final volumes determined. Differences between initial and final volumes and travel distances will yield a distribution of attrition rates and, therefore, a mean gravel attrition rate.

  13. Development of an attrition risk prediction tool.

    Science.gov (United States)

    Fowler, John; Norrie, Peter

    To review lecturers' and students' perceptions of the factors that may lead to attrition from pre-registration nursing and midwifery programmes and to identify ways to reduce the impact of such factors on the student's experience. Comparable attrition rates for nursing and midwifery students across various universities are difficult to monitor accurately; however, estimates that there is approximately a 25% national attrition rate are not uncommon. The financial and human implications of this are significant and worthy of investigation. A study was carried out in one medium-sized UK school of nursing and midwifery, aimed at identifying perceived factors associated with attrition and retention. Thirty-five lecturers were interviewed individually; 605 students completed a questionnaire, and of these, 10 were individually interviewed. Attrition data kept by the student service department were reviewed. Data were collected over an 18-month period in 2007-2008. Regression analysis of the student data identified eight significant predictors. Four of these were 'positive' factors in that they aided student retention and four were 'negative' in that they were associated with students' thoughts of resigning. Student attrition and retention is multifactorial, and, as such, needs to be managed holistically. One aspect of this management could be an attrition risk prediction tool.

  14. No differential attrition was found in randomized controlled trials published in general medical journals: a meta-analysis.

    Science.gov (United States)

    Crutzen, Rik; Viechtbauer, Wolfgang; Kotz, Daniel; Spigt, Mark

    2013-09-01

    Differential attrition is regarded as a major threat to the internal validity of a randomized controlled trial (RCT). This study identifies the degree of differential attrition in RCTs covering a broad spectrum of clinical areas and factors that are related to this. A PubMed search was conducted to obtain a random sample of 100 RCTs published between 2008 and 2010 in journals from the ISI Web of Knowledge(SM) category of medicine, general and internal. Eligibility criteria for selecting studies were primary publications of two-arm parallel randomized clinical trials, containing human participants and one or multiple follow-up measurements whose availability depended on the patients' willingness to participate. A significant amount of differential attrition was observed in 8% of the trials. The average differential attrition rate was 0.99 (95% confidence interval: 0.97-1.01), indicating no general difference in attrition rates between intervention and control groups. Moreover, no indication of heterogeneity was found, suggesting that the occurrence of differential attrition in the published literature is mostly a chance finding, unrelated to any particular design factors. Differential attrition did not generally occur in RCTs covering a broad spectrum of clinical areas within general and internal medicine. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. Regional Disparities in Apprentice Attrition Rates: Heat and Quarter Four's Significance in Northern Australia

    Science.gov (United States)

    Zoellner, Don; Brearley, Matt; Oppermann, Elspeth

    2017-01-01

    Apprenticeship completion rates have remained persistently low for decades in spite of broad agreement over the causes of non-completions. A possible factor missing from these explanations is climate, particularly in northern Australia where traditional trade apprentices are exposed to extreme conditions and exert themselves. We hypothesize that:…

  16. The AMIGO Clinical Study: Attrition Rates Among Military Beneficiaries Undergoing Intensive Group Outpatient Pre-Diabetes Care

    Science.gov (United States)

    2013-11-11

    inactivity and obesity have been observed to serve as catalysts to hasten disease progression. 1,2 A worldwide epidemic, the treatment of this...military treatment facility. The purpose of this study was to decrease the incidence of progression from pre-diabetes to diabetes by evaluating the...or lactating  Patients with untreated hypothyroidism or previously diagnosed Cushing’s syndrome  Patients currently taking metformin or

  17. Waiting Time Increases Risk of Attrition in Gambling Disorder Treatment

    DEFF Research Database (Denmark)

    Linnet, Jakob; Pedersen, Anders Sune

    2014-01-01

    Attrition is a well known problem in psychotherapeutic treatment. Patients with addiction have high attrition rates, and it is therefore important to identify factors that can improve completion rates in addiction. Here, we investigated the influence of waiting time as a predictor of treatment...

  18. Study of Navy Enlisted Attrition: Race, Ethnicity, and Type of Occupation

    National Research Council Canada - National Science Library

    Carroll, James M

    2008-01-01

    The primary objective of this study is to gain a better understanding of Navy first-term enlisted attrition among racial/ethnic minorities by comparing attrition rates in technical and nontechnical occupations...

  19. Evaluating Teacher Preparation Using Graduates' Observational Ratings

    Science.gov (United States)

    Ronfeldt, Matthew; Campbell, Shanyce L.

    2016-01-01

    Despite growing calls for more accountability of teacher education programs (TEPs), there is little consensus about how to evaluate them. This study investigates the potential for using observational ratings of program completers to evaluate TEPs. Drawing on statewide data on almost 9,500 program completers, representing 44 providers (183…

  20. The measurement of change in functional ability: dealing with attrition and the floor/ceiling effect

    DEFF Research Database (Denmark)

    Holstein, Bjørn E; Avlund, Kirsten; Due, Pernille

    2006-01-01

    , functional ability at baseline, relative wealth, social network, self-rated health, and life-satisfaction. Inclusion of the dead in statistical models for the study of change in functional ability reduced the attrition problem. A logistic model for paired observations of functional ability at two points...

  1. Texas Public School Attrition Study, 2011-12. IDRA Report

    Science.gov (United States)

    Johnson, Roy L.; Montes, Felix

    2012-01-01

    This document contains 3 statistical reports. The first report, "Attrition Rate Decline Seems Promising--Though High Schools are Still Losing One in Four Students" (by Roy L. Johnson), presents results of long-term trend assessments of attrition data in Texas public high schools. The second report, "Slow Declining Pace Keeps Zero…

  2. A qualitative and quantitative study of the reasons of attrition in an Indian hospital

    Directory of Open Access Journals (Sweden)

    Kasturi Shukla

    2017-01-01

    Full Text Available Background: The study attempts to evaluate the reasons of attrition in the organization from the perspective of the existing as well as the leaving employees; compare and identify the gaps, if any between the perspectives of these two employees groups. The study also aims to critically analyze the utility of ′exit interviews′ for analyzing the reasons of attrition. Methods: This cross-sectional study was conducted in a 150-bedded hospital in Ahmedabad, India, during May-July 2015. Exit interview data of forty leaving employees were collected and reviewed. One hundred existing employees were interviewed through quantitative and qualitative methods to understand their perceptions about attrition in the organization. Results: Attrition rate of 26% was observed in the study and 57% leaving employees were nurses. 70% leaving employees cite "blanket reasons" such as better opportunity and personal reasons during exit interviews. 72.5% leaving employees believed that exit interview is largely for record purpose and 11% were unsure of its utility. However, when existing employees were probed qualitatively, a variety of responses were received. 65% existing employees quoted salary issues, partiality/poor recognition, improper assignment of tasks, and monotonous work as reasons for attrition in the organization. Conclusion: Exit interviews somewhere fail to probe into the real reasons of attrition. To improve retention, organizations must monitor their existing employee′s intention to continue working in the organization and any sign indicating a poor intention to continue must be addressed immediately to avoid ripple effects. Moreover, to use exit interview as a tool to improve employee retention, leaving employees must be interviewed in-depth to uncover the actual reasons for quitting the job.

  3. Language Attrition: The Fate of the Start.

    Science.gov (United States)

    Hansen, Lynne

    2001-01-01

    Reviews the literature on psycholinguistic aspects of language attrition over the past half decade. Discusses evidence from studies on hesitation phenomena in attriter speech, variables affecting language attrition, and relearning. (Author/VWL)

  4. Limestone particle attrition and size distribution in a small circulating fluidized bed

    Energy Technology Data Exchange (ETDEWEB)

    Zhongxiang Chen; John R. Grace; C. Jim Lim [University of British Columbia, Vancouver, BC (Canada). Department of Chemical and Biological Engineering

    2008-06-15

    Limestone particle attrition was investigated in a small circulating fluidized bed reactor at temperatures from 25 to 850{sup o}C, 1 atm pressure and superficial gas velocities from 4.8 to 6.2 m/s. The effects of operating time, superficial gas velocity and temperature were studied with fresh limestone. No calcination or sulfation occurred at temperatures {le} 580{sup o}C, whereas calcination and sulfation affected attrition at 850{sup o}C. Increasing the temperature (while maintaining the same superficial gas velocity) reduced attrition if there was negligible calcination. Attrition was high initially, but after about 24 h, the rate of mass change became constant. The ratio of initial mean particle diameter to that at later times increased linearly with time and with (U{sub g} - U{sub mf}){sup 2}, while decreasing exponentially with temperature, with an activation energy for fresh limestone of -4.3 kJ/mol. The attrition followed Rittinger's surface theory. The change of surface area of limestone particles was proportional to the total excess kinetic energy consumed and to the total attrition time, whereas the change of surface area decreased exponentially with increasing temperature. At 850{sup o}C, the attrition rate of calcined lime was highest, whereas the attrition rate was lowest for sulfated particles. When online impact attrition was introduced, the attrition rate was about an order of magnitude higher than without impacts. 25 refs., 14 figs., 4 tabs.

  5. Military Personnel Attrition and Retention: Research in Progress

    Science.gov (United States)

    1981-10-01

    NATIONAL ANALYSES OF ATTRITION 13 H. Wallace Sinaiko and Kenneth C. Scheflen AIR FORCE ATTRITION RESEARCH: ANALISIS OF PRE- AND POST- 15 ENLISTMENT FACTORS...are specific types ot codes used, to icdentity categories of reenlistments, extensions, and losses. These SPD codes will be clustered in various ways...two enlistment terms in the Navy. The Navy’s 110 ratings were grouped into 24 occupational tields which represented clusters of similar skills, similar

  6. Workshop on Language Student Attrition

    National Research Council Canada - National Science Library

    Whelan, Bree

    2001-01-01

    Seventy individuals from Government agencies (military and civilian), academia, and contractor organizations attended all or parts of a Workshop on student Attrition held at the Defense Language Institute Foreign Language Center (DLIFLC...

  7. Predictors of early faculty attrition at one Academic Medical Center.

    Science.gov (United States)

    Bucklin, Brenda A; Valley, Morgan; Welch, Cheryl; Tran, Zung Vu; Lowenstein, Steven R

    2014-02-10

    Faculty turnover threatens the research, teaching and clinical missions of medical schools. We measured early attrition among newly-hired medical school faculty and identified personal and institutional factors associated with early attrition. This retrospective cohort study identified faculty hired during the 2005-2006 academic year at one school. Three-year attrition rates were measured. A 40-question electronic survey measured demographics, career satisfaction, faculty responsibilities, institutional/departmental support, and reasons for resignation. Odds ratios (ORs) and 95 percent confidence intervals (95% CI) identified variables associated with early attrition. Of 139 faculty, 34% (95% CI = 26-42%) resigned within three years of hire. Attrition was associated with: perceived failure of the Department Chair to foster a climate of teaching, research, and service (OR = 6.03; 95% CI: 1.84, 19.69), inclusiveness, respect, and open communication (OR = 3.21; 95% CI: 1.04, 9.98). Lack of professional development of the faculty member (OR = 3.84; 95% CI: 1.25, 11.81); institutional recognition and support for excellence in teaching (OR = 2.96; 95% CI: 0.78, 11.19) and clinical care (OR = 3.87; 95% CI: 1.04, 14.41); and >50% of professional time devoted to patient care (OR = 3.93; 95% CI: 1.29, 11.93) predicted attrition. Gender, race, ethnicity, academic degree, department type and tenure status did not predict early attrition. Of still-active faculty, an additional 27 (48.2%, 95% CI: 35.8, 61.0) reported considering resignation within the 5 years. In this pilot study, one-third of new faculty resigned within 3 years of hire. Greater awareness of predictors of early attrition may help schools identify threats to faculty career satisfaction and retention.

  8. Factors Influencing Students' Attrition at Sultan Qaboos University (SQU)

    Science.gov (United States)

    Al Ghanboosi, Salim Saleen

    2013-01-01

    The students' attrition rates among students enrolled at SQU ranged between 6.8% (1998), 7.8% (1999), and 7.9% (2000). However, the drop-out rate at the Sultan Qaboos University is increasing gradually, and this increase represents a problem for the university that provides free education and financial aid for all male students coming from areas…

  9. The Case for Increasing Workplace Decision-Making: Proposing a Model for Special Educator Attrition Research

    Science.gov (United States)

    Tyler, Teresa A.; Brunner, C. Cryss

    2014-01-01

    The chronically high rate of special educator attrition across U.S. schools creates a dilemma for educational leaders because special educators provide direct services to students with special needs. Attrition exacerbates already high special educator shortages reported in most districts, and nearly one million schoolchildren with disabilities…

  10. "Should I Stay or Should I Go?": Unpacking Teacher Attrition/Retention as an Educational Issue

    Science.gov (United States)

    Kelchtermans, Geert

    2017-01-01

    The paper starts from the observation that teacher attrition/retention seems to be a wicked issue: it seems to have strong face validity and a commonsense meaning, but the literature doesn't provide a clear and distinctive definition. In the first section, the author analyzes the different ways in which the issue of teacher attrition and retention…

  11. Attrition of undergraduate nursing students at selected South African universities

    Directory of Open Access Journals (Sweden)

    Erna Roos

    2016-08-01

    Full Text Available Background: The nursing profession forms the backbone of many healthcare systems. It therefore needs a consistent supply of registered nurses to deliver continuous and safe quality healthcare, and to replace the nurses leaving or retiring from the profession. Attrition actively occurs among nursing students in South Africa and threatens the future supply of registered nurses. Aim: The aim of the study was to describe the attrition rate at selected South African universities and the factors influencing undergraduate nursing students to discontinue their nursing studies at these universities. Method: A quantitative descriptive design was followed. Heads of the nursing departments at the selected universities captured data with a specifically designed questionnaire. Thereafter their former nursing students provided information via a structured telephonic interview on the reasons why they discontinued the nursing programme. Results: The study revealed that attrition of undergraduate nursing students for three intake years (2007, 2008 and 2009 at the participating universities was between 39.3% and 58.7%. Academic and financial reasons as well as poor wellness and health were the main causes for attrition. Another factor was failure to cope with the demands of the clinical environment. Conclusion: Attrition might not occur immediately when a nursing student is challenged, as the student might exploit the various types of support offered. Although some nursing students do benefit from the offered support, a large number of nursing students still discontinue the undergraduate nursing programme.

  12. Preliminary observation of genital secretions, growth rate and ...

    African Journals Online (AJOL)

    Cane rats are large terrestial rodents which have the potential to increase animal protein intake. There is paucity of information on the genital secretions and growth rate of caged cane rats. This study observed the genital secretions, growth rate, feeds, feeding and the behaviour of caged cane rats. When animals adjusted to ...

  13. Personal, Situational, and Organizational Determinants of Navy Enlisted Attrition

    Science.gov (United States)

    1980-06-01

    of regular high school instruction. The GED test battery contains five testsz writing skills, social studies, science, reading skills, and mathematics ...expanded apprentice train- ing program for airmen and seamen might, ceteris paribus, bring the GENDET attrition rate closer to acceptable lvels . 13 ] KN

  14. Navy Recruit Attrition Prediction Modeling

    Science.gov (United States)

    2014-09-01

    have high correlation with attrition, such as age, job characteristics, command climate, marital status, behavior issues prior to recruitment, and the...the additive model. glm(formula = Outcome ~ Age + Gender + Marital + AFQTCat + Pay + Ed + Dep, family = binomial, data = ltraining) Deviance ...0.1 ‘ ‘ 1 (Dispersion parameter for binomial family taken to be 1) Null deviance : 105441 on 85221 degrees of freedom Residual deviance

  15. Understanding attrition from international Internet health interventions: a step towards global eHealth.

    Science.gov (United States)

    Geraghty, Adam W A; Torres, Leandro D; Leykin, Yan; Pérez-Stable, Eliseo J; Muñoz, Ricardo F

    2013-09-01

    Worldwide automated Internet health interventions have the potential to greatly reduce health disparities. High attrition from automated Internet interventions is ubiquitous, and presents a challenge in the evaluation of their effectiveness. Our objective was to evaluate variables hypothesized to be related to attrition, by modeling predictors of attrition in a secondary data analysis of two cohorts of an international, dual language (English and Spanish) Internet smoking cessation intervention. The two cohorts were identical except for the approach to follow-up (FU): one cohort employed only fully automated FU (n = 16 430), while the other cohort also used 'live' contact conditional upon initial non-response (n = 1000). Attrition rates were 48.1 and 10.8% for the automated FU and live FU cohorts, respectively. Significant attrition predictors in the automated FU cohort included higher levels of nicotine dependency, lower education, lower quitting confidence and receiving more contact emails. Participants' younger age was the sole predictor of attrition in the live FU cohort. While research on large-scale deployment of Internet interventions is at an early stage, this study demonstrates that differences in attrition from trials on this scale are (i) systematic and predictable and (ii) can largely be eliminated by live FU efforts. In fully automated trials, targeting the predictors we identify may reduce attrition, a necessary precursor to effective behavioral Internet interventions that can be accessed globally.

  16. Beyond student ratings: peer observation of classroom and clinical teaching.

    Science.gov (United States)

    Berk, Ronald A; Naumann, Phyllis L; Appling, Susan E

    2004-01-01

    Peer observation of classroom and clinical teaching has received increased attention over the past decade in schools of nursing to augment student ratings of teaching effectiveness. One essential ingredient is the scale used to evaluate performance. A five-step systematic procedure for adapting, writing, and building any peer observation scale is described. The differences between the development of a classroom observation scale and an appraisal scale to observe clinical instructors are examined. Psychometric issues peculiar to observation scales are discussed in terms of content validity, eight types of response bias, and interobserver reliability. The applications of the scales in one school of nursing as part of the triangulation of methods with student ratings and the teaching portfolio are illustrated. Copies of the scales are also provided.

  17. 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

  18. Attrition from Web-Based Cognitive Testing: A Repeated Measures Comparison of Gamification Techniques.

    Science.gov (United States)

    Lumsden, Jim; Skinner, Andy; Coyle, David; Lawrence, Natalia; Munafo, Marcus

    2017-11-22

    The prospect of assessing cognition longitudinally and remotely is attractive to researchers, health practitioners, and pharmaceutical companies alike. However, such repeated testing regimes place a considerable burden on participants, and with cognitive tasks typically being regarded as effortful and unengaging, these studies may experience high levels of participant attrition. One potential solution is to gamify these tasks to make them more engaging: increasing participant willingness to take part and reducing attrition. However, such an approach must balance task validity with the introduction of entertaining gamelike elements. This study aims to investigate the effects of gamelike features on participant attrition using a between-subjects, longitudinal Web-based testing study. We used three variants of a common cognitive task, the Stop Signal Task (SST), with a single gamelike feature in each: one variant where points were rewarded for performing optimally; another where the task was given a graphical theme; and a third variant, which was a standard SST and served as a control condition. Participants completed four compulsory test sessions over 4 consecutive days before entering a 6-day voluntary testing period where they faced a daily decision to either drop out or continue taking part. Participants were paid for each session they completed. A total of 482 participants signed up to take part in the study, with 265 completing the requisite four consecutive test sessions. No evidence of an effect of gamification on attrition was observed. A log-rank test showed no evidence of a difference in dropout rates between task variants (χ 2 2 =3.0, P=.22), and a one-way analysis of variance of the mean number of sessions completed per participant in each variant also showed no evidence of a difference (F 2,262 =1.534, P=.21, partial η 2 =0.012). Our findings raise doubts about the ability of gamification to reduce attrition from longitudinal cognitive testing studies

  19. The relationship between beginning teachers' stress causes, stress responses, teaching behaviour and attrition

    NARCIS (Netherlands)

    Harmsen, Ruth; Lorenz, Michelle; Maulana, Ridwan; van Veen, Klaas

    2018-01-01

    In this study, the relationships between beginning teachers’ perceived stress causes, stress responses, observed teaching behaviour and attrition is investigated employing structural equation modelling (SEM). A total of 143 BTs were surveyed using the Questionnaire on the Experience and Evaluation

  20. A Comparative Study of Administrator and Special Education Teacher Perceptions of Special Education Teacher Attrition and Retention

    Science.gov (United States)

    Sheldrake, Danielle Angelina

    2013-01-01

    This mixed methods study identifies perceived causes of and solutions to the attrition of special education teachers. Researchers have documented that special education teaching positions encounter higher attrition rates than their general education peers (Katsiyannis, Zhang, & Conroy in Olivarez & Arnold, 2006; Mitchell & Arnold,…

  1. Attrition in a 30-year follow-up of a perinatal birth risk cohort: factors change with age

    Directory of Open Access Journals (Sweden)

    Jyrki Launes

    2014-07-01

    Full Text Available Background. Attrition is a major cause of potential bias in longitudinal studies and clinical trials. Attrition rate above 20% raises concern of the reliability of the results. Few studies have looked at the factors behind attrition in follow-ups spanning decades.Methods. We analyzed attrition and associated factors of a 30-year follow-up cohort of subjects who were born with perinatal risks for neurodevelopmental disorders. Attrition rates were calculated at different stages of follow-up and differences between responders and non-responders were tested. To find combinations of variables influencing attrition and investigate their relative importance at birth, 5, 9, 16 and 30 years of follow-up we used the random forest classification.Results. Initial loss of potential participants was 13%. Attrition was 16% at five, 24% at nine, 35% at 16 and 46% at 30 years. The only group difference that emerged between responders and non-responders was in socioeconomic status (SES. The variables identified by random forest classification analysis were classified into Birth related, Development related and SES related. Variables from all these categories contributed to attrition, but SES related variables were less important than birth and development associated variables. Classification accuracy ranged between 0.74 and 0.96 depending on age.Discussion. Lower SES is linked to attrition in many studies. Our results point to the importance of the growth and development related factors in a longitudinal study. Parents’ decisions to participate depend on the characteristics of the child. The same association was also seen when the child, now grown up, decided to participate at 30 years. In addition, birth related medical variables are associated with the attrition still at the age of 30. Our results using a data mining approach suggest that attrition in longitudinal studies is influenced by complex interactions of a multitude of variables, which are not

  2. Lanchester's attrition models and fights among social animals

    OpenAIRE

    Eldridge S. Adams; Michael Mesterton-Gibbons

    2003-01-01

    Lanchester's models of attrition during warfare have served as the basis for several predictions about conflicts between groups of animals. These models and their extensions describe rates of mortality during battles as functions of the number and fighting abilities of individuals in each group, allowing analysis of the determinants of group strength and of the cumulative numbers of casualties. We propose modifications to Lanchester's models to improve their applicability to social animals. I...

  3. Military Enlistment and Attrition. An Analysis of Decision Reversal

    Science.gov (United States)

    1987-06-01

    instability, defined as being unemployed at the time of enlistment or having had a spell of jobless- ness within the past 12 months. For graduates, attrition...opportunities. The level of education an individual obtains is related to the value of higher education to the individual (both monetary and psychic ...value, does suggest that unemployed graduates are more likely to enlist, all other things equal, the higher their previous wage rate. The previous

  4. Fast radio burst event rate counts - I. Interpreting the observations

    Science.gov (United States)

    Macquart, J.-P.; Ekers, R. D.

    2018-02-01

    The fluence distribution of the fast radio burst (FRB) population (the `source count' distribution, N (>F) ∝Fα), is a crucial diagnostic of its distance distribution, and hence the progenitor evolutionary history. We critically reanalyse current estimates of the FRB source count distribution. We demonstrate that the Lorimer burst (FRB 010724) is subject to discovery bias, and should be excluded from all statistical studies of the population. We re-examine the evidence for flat, α > -1, source count estimates based on the ratio of single-beam to multiple-beam detections with the Parkes multibeam receiver, and show that current data imply only a very weak constraint of α ≲ -1.3. A maximum-likelihood analysis applied to the portion of the Parkes FRB population detected above the observational completeness fluence of 2 Jy ms yields α = -2.6_{-1.3}^{+0.7 }. Uncertainties in the location of each FRB within the Parkes beam render estimates of the Parkes event rate uncertain in both normalizing survey area and the estimated post-beam-corrected completeness fluence; this uncertainty needs to be accounted for when comparing the event rate against event rates measured at other telescopes.

  5. Observational Test of the Dayside Magnetopause Reconnection Rate

    Science.gov (United States)

    Wang, S.; Kistler, L. M.; Mouikis, C.

    2014-12-01

    In asymmetric reconnection, the reconnection rate (R) is expected to follow the Cassak-Shay formula with an aspect ratio of around 0.1. At the magnetopause, reconnection is asymmetric, with the dense shocked solar wind population on the magnetosheath side, and a normally hot and tenuous population on the magnetospheric side. However, the hot magnetospheric population can contain a significant O+ component that increases the mass density, and the magnetospheric population may also include a cold dense population of plasmaspheric origin. We perform a statistical study of 13 magnetopause reconnection events observed by Cluster to determine how the reconnection rate depends on these different populations. The events are mainly at high latitudes, due to the Cluster orbit. Our results show that the measured R generally follows the Cassak-Shay prediction when all populations are included. However, the predicted rate only considering the magnetosheath contribution also correlates well with the measured R. For individual events, cold ions can make a comparable contribution to the magnetosheath H+ when there are plasmaspheric drainage plumes; the contribution of the magnetospheric hot O+ can be up to ~30%. However, the variation of solar wind conditions has a larger effect on the variation in the reconnection rate. The aspect ratio does not vary systematically with the O+ content, and 0.1 is a reasonable estimation. The outflow velocity is around the hybrid Alfven speed, but there is not a strong correlation. This may be due to motion of the x-line, or effects of the magnetosheath shear flow.

  6. The Canadian Forces Recruitment/Attrition Model

    National Research Council Canada - National Science Library

    Wait, Tracey

    1998-01-01

    ...), as part of its mandate to provide analysis of potential impacts of trends and change on defense and defense related issues, has designed a prototype model of recruitment and attrition of the Canadian Forces (C F...

  7. Estimation of human core temperature from sequential heart rate observations

    International Nuclear Information System (INIS)

    Buller, Mark J; Tharion, William J; Cheuvront, Samuel N; Montain, Scott J; Kenefick, Robert W; Castellani, John; Latzka, William A; Hoyt, Reed W; Roberts, Warren S; Richter, Mark; Jenkins, Odest Chadwicke

    2013-01-01

    Core temperature (CT) in combination with heart rate (HR) can be a good indicator of impending heat exhaustion for occupations involving exposure to heat, heavy workloads, and wearing protective clothing. However, continuously measuring CT in an ambulatory environment is difficult. To address this problem we developed a model to estimate the time course of CT using a series of HR measurements as a leading indicator using a Kalman filter. The model was trained using data from 17 volunteers engaged in a 24 h military field exercise (air temperatures 24–36 °C, and 42%–97% relative humidity and CTs ranging from 36.0–40.0 °C). Validation data from laboratory and field studies (N = 83) encompassing various combinations of temperature, hydration, clothing, and acclimation state were examined using the Bland–Altman limits of agreement (LoA) method. We found our model had an overall bias of −0.03 ± 0.32 °C and that 95% of all CT estimates fall within ±0.63 °C (>52 000 total observations). While the model for estimating CT is not a replacement for direct measurement of CT (literature comparisons of esophageal and rectal methods average LoAs of ±0.58 °C) our results suggest it is accurate enough to provide practical indication of thermal work strain for use in the work place. (paper)

  8. Estimation of human core temperature from sequential heart rate observations.

    Science.gov (United States)

    Buller, Mark J; Tharion, William J; Cheuvront, Samuel N; Montain, Scott J; Kenefick, Robert W; Castellani, John; Latzka, William A; Roberts, Warren S; Richter, Mark; Jenkins, Odest Chadwicke; Hoyt, Reed W

    2013-07-01

    Core temperature (CT) in combination with heart rate (HR) can be a good indicator of impending heat exhaustion for occupations involving exposure to heat, heavy workloads, and wearing protective clothing. However, continuously measuring CT in an ambulatory environment is difficult. To address this problem we developed a model to estimate the time course of CT using a series of HR measurements as a leading indicator using a Kalman filter. The model was trained using data from 17 volunteers engaged in a 24 h military field exercise (air temperatures 24-36 °C, and 42%-97% relative humidity and CTs ranging from 36.0-40.0 °C). Validation data from laboratory and field studies (N = 83) encompassing various combinations of temperature, hydration, clothing, and acclimation state were examined using the Bland-Altman limits of agreement (LoA) method. We found our model had an overall bias of -0.03 ± 0.32 °C and that 95% of all CT estimates fall within ±0.63 °C (>52 000 total observations). While the model for estimating CT is not a replacement for direct measurement of CT (literature comparisons of esophageal and rectal methods average LoAs of ±0.58 °C) our results suggest it is accurate enough to provide practical indication of thermal work strain for use in the work place.

  9. Determination of the attrition resistance of granular charcoals

    International Nuclear Information System (INIS)

    Dietz, V.R.

    1979-01-01

    A laboratory procedure has been developed to evaluate the attrition of granular adsorbent charcoals on passing an air flow through the bed. Two factors observed in plant operations were selected as relevant: (1) the characteristic structural vibrations in plant scale equipment (motors, fans, etc.) that are transmitted to charcoal particles and cause the particles to move and rub each other, and (2) the rapid air flow that results in the movement of the attrited dust. In the test a container for charcoal [50 mm diameter and 50 mm high] was vibrated at a frequency of 60 Hz and at a constant energy input manually controlled using a vibration meter in the acceleration mode. Simultaneously, air was applied and exited through glass fiber filter paper. The quantity of dust trapped on the exit filter was then determined, either optically or gravimetrically. The dust formed per minute (attrition coefficient) was found to approach a constant value. The plateau-values from sequential determinations varied with the source of the charcoal; a 5-fold difference was found among a large variety of commercial products. The first testing of a sample released the excess dust accumulated in previous handling of the charcoal. The plateau values were then attained in the succeeding tests and these were characteristic of the material. The results were compared with those obtained for the same charcoals using older test methods such as the Ball and Pan Hardness Test described in RDTM16-1T

  10. A Self-Regulation-Based eHealth Intervention to Promote a Healthy Lifestyle: Investigating User and Website Characteristics Related to Attrition.

    Science.gov (United States)

    Van der Mispel, Celien; Poppe, Louise; Crombez, Geert; Verloigne, Maïté; De Bourdeaudhuij, Ilse

    2017-07-11

    eHealth interventions can reach large populations and are effective in increasing physical activity (PA) and fruit and vegetable intake. Nevertheless, the effects of eHealth interventions are overshadowed by high attrition rates. Examining more closely when users decide to leave the intervention can help eHealth developers to make informed decisions about which intervention components should be reshaped or simply removed. Investigating which users are more likely to quit an intervention can inform developers about whether and how their intervention should be adapted to specific subgroups of users. This study investigated the pattern of attrition in a Web-based intervention to increase PA, fruit, and vegetable intake. The first aim was to describe attrition rates according to different self-regulation components. A second aim was to investigate whether certain user characteristics are predictors for start session completion, returning to a follow-up session and intervention completion. The sample consisted of 549 adults who participated in an online intervention, based on self-regulation theory, to promote PA and fruit and vegetable intake, called "MyPlan 1.0." Using descriptive analysis, attrition was explored per self-regulation component (eg, action planning and coping planning). To identify which user characteristics predict completion, logistic regression analyses were conducted. At the end of the intervention program, there was an attrition rate of 78.2% (330/422). Attrition rates were very similar for the different self-regulation components. However, attrition levels were higher for the fulfillment of questionnaires (eg, to generate tailored feedback) than for the more interactive components. The highest amount of attrition could be observed when people were asked to make their own action plan. There were no significant predictors for first session completion. Yet, two subgroups had a lower chance to complete the intervention, namely male users (OR: 2.24, 95

  11. Unemployment, the Great Recession, and Apprenticeship Attrition in the U.S.

    Science.gov (United States)

    Bilginsoy, Cihan

    2018-01-01

    The author estimates the impacts of the local rate of unemployment and the Great Recession on the quit and graduation rates of the U.S. construction trade apprentices over the 2001-2014 period. Trade union participation in training sponsorship had a strong influence on attrition rates. The impacts of the business cycle and the Great Recession on…

  12. Self-esteem and self-efficacy as predictors of attrition in associate degree nursing students.

    Science.gov (United States)

    Peterson-Graziose, Virginia; Bryer, Jennifer; Nikolaidou, Maria

    2013-06-01

    There is a serious and growing shortage of nurses in the United States, and the high rate of student attrition from nursing programs has further added to this problem. The challenge for schools of nursing is to recruit increased numbers of qualified candidates into their programs and to determine ways to decrease the rate of student attrition. The purpose of this study was to determine whether self-esteem, self-efficacy, and life stressors were significantly related to student attrition in first-semester associate degree nursing students. A descriptive correlational design and nonprobability convenience sample of first-semester associate degree nursing students was used. Data were gathered using the Rosenberg Self-Esteem Scale, the General Self-Efficacy Scale, and the Holmes and Rahe Social Readjustment Rating Scale. Findings indicated that self-esteem was significantly associated with student attrition. Results from this study provide the basis for targeted interventions designed to decrease student attrition rates in associate degree nursing programs. Copyright 2013, SLACK Incorporated.

  13. Inverse modelling of radionuclide release rates using gamma dose rate observations

    Science.gov (United States)

    Hamburger, Thomas; Evangeliou, Nikolaos; Stohl, Andreas; von Haustein, Christoph; Thummerer, Severin; Wallner, Christian

    2015-04-01

    Severe accidents in nuclear power plants such as the historical accident in Chernobyl 1986 or the more recent disaster in the Fukushima Dai-ichi nuclear power plant in 2011 have drastic impacts on the population and environment. Observations and dispersion modelling of the released radionuclides help to assess the regional impact of such nuclear accidents. Modelling the increase of regional radionuclide activity concentrations, which results from nuclear accidents, underlies a multiplicity of uncertainties. One of the most significant uncertainties is the estimation of the source term. That is, the time dependent quantification of the released spectrum of radionuclides during the course of the nuclear accident. The quantification of the source term may either remain uncertain (e.g. Chernobyl, Devell et al., 1995) or rely on estimates given by the operators of the nuclear power plant. Precise measurements are mostly missing due to practical limitations during the accident. The release rates of radionuclides at the accident site can be estimated using inverse modelling (Davoine and Bocquet, 2007). The accuracy of the method depends amongst others on the availability, reliability and the resolution in time and space of the used observations. Radionuclide activity concentrations are observed on a relatively sparse grid and the temporal resolution of available data may be low within the order of hours or a day. Gamma dose rates, on the other hand, are observed routinely on a much denser grid and higher temporal resolution and provide therefore a wider basis for inverse modelling (Saunier et al., 2013). We present a new inversion approach, which combines an atmospheric dispersion model and observations of radionuclide activity concentrations and gamma dose rates to obtain the source term of radionuclides. We use the Lagrangian particle dispersion model FLEXPART (Stohl et al., 1998; Stohl et al., 2005) to model the atmospheric transport of the released radionuclides. The

  14. Incorporating direct marketing activity into latent attrition models

    NARCIS (Netherlands)

    Schweidel, David A.; Knox, George

    2013-01-01

    When defection is unobserved, latent attrition models provide useful insights about customer behavior and accurate forecasts of customer value. Yet extant models ignore direct marketing efforts. Response models incorporate the effects of direct marketing, but because they ignore latent attrition,

  15. Retention and Attrition Among African Americans in the STAR*D Study: What Causes Research Volunteers to Stay or Stray?

    Science.gov (United States)

    Murphy, Eleanor J; Kassem, Layla; Chemerinski, Anat; Rush, A. John; Laje, Gonzalo; McMahon, Francis J.

    2013-01-01

    Background High attrition rates among African-Americans (AA) volunteers are a persistent problem that makes clinical trials less representative and complicates estimation of treatment outcomes. Many studies contrast AA with other ethnic/racial groups, but few compare the AA volunteers who remain in treatment with those who leave. Here, in addition to comparing patterns of attrition between African Americans and whites, we identify predictors of overall and early attrition among African Americans. Method Sample comprised non-Hispanic African-American (n=673) and white (n=2,549) participants in the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study. Chi-square tests were used to examine racial group differences in reasons for exit. Multivariate logistic regression was used to examine predictors of overall attrition, early attrition (by Level 2) and top reasons cited for attrition among African Americans. Results For both African-American and white dropouts, non-compliance reasons for attrition were most commonly cited during the earlier phases of the study while reasons related to efficacy and medication side effects were cited later in the study. Satisfaction with treatment strongly predicted overall attrition among African Americans independent of socioeconomic, clinical, medical or psychosocial factors. Early attrition among African American dropouts was associated with less psychiatric comorbidity, and higher perceived physical functioning but greater severity of clinician-rated depression. Conclusions The decision to drop out is a dynamic process that changes over the course of a clinical trial. Strategies aimed at retaining African Americans in such trials should emphasize engagement with treatment and patient satisfaction immediately following enrollment and after treatment initiation. PMID:23723044

  16. An experimental study on the primary fragmentation and attrition of limestones in a fluidized bed

    International Nuclear Information System (INIS)

    Yao, Xuan; Zhang, Hai; Yang, Hairui; Liu, Qing; Wang, Jinwei; Yue, Guangxi

    2010-01-01

    In this paper, an experimental study on the primary fragmentation and attrition of 5 limestones in a fluidized bed was conducted. The intensity of fragmentation and attrition were measured in the same apparatus but at different fluidizing velocities. It was found that the averaged size of the particles decreased by about 10-20% during the fragmentation process. The important factors for particle comminution include limestone types, heating rate, calcination condition and ambient CO 2 concentration. Fragmentation mainly occurred in the first a few minutes in the fluidized bed and it was more intense than that in the muffle furnace at the same temperature. The original size effect was ambiguous, depending on the limestone type. The comminution caused by attrition mainly occurred during calcination process rather than sulphation process. The sulphation process was fragmentation and attrition resisted. The attrition rate of sulphate was similar to that of lime in trend, decaying exponentially with time, but was one-magnitude-order smaller than that of lime. Present experimental results indicate that fragmentation mechanism of the limestone is dominated by CO 2 release instead of thermal stress. (author)

  17. Inter-Observer Agreement in Measuring Respiratory Rate

    DEFF Research Database (Denmark)

    Nielsen, Louise Gramstrup; Folkestad, Lars; Brodersen, Jacob Broder

    2015-01-01

    BACKGROUND: Respiratory rate (RR) is an important vital sign which is strongly correlated with in-hospital mortality. At the same time, RR is the most likely vital sign to be omitted when assessing a patient. We believe that one reason for this could be the difficulty in measure the RR, since...

  18. Factors of Attrition in Cohort Doctoral Education: A Self-Determination Theory Perspective

    Science.gov (United States)

    Garcia, Linda Ann

    2013-01-01

    Attrition rates, completion rates, and time to degree are the key areas researchers have sought to examine influencing factors and patterns of behavior that describe the departure process of students in doctoral study. Through the lens of self-determination theory (Deci & Ryan, 1985), the purpose of this phenomenological qualitative study was…

  19. Mass loss rates of OB stars derived from infrared observations

    International Nuclear Information System (INIS)

    Tanzi, E.G.; Tarenghi, M.; Panagia, N.

    1981-01-01

    In this paper the authors report briefly on a study of the mass loss of early type stars in the infrared. Up to now near infrared (1.25 - 4.8 μ) broad band photometry of 70 southern OB stars of various luminosity class has been secured. Program stars have been selected, among those bright enough in the infrared to give a suitable photometric accuracy, in order to cover a wide range of spectral types. 37 stars are found to exhibit emission in excess over a blackbody photospheric continuum, which is interpreted in terms of gas ejected in the form of an accelerated wind. By means of model calculations the corresponding mass loss rates are derived. The obtained values compare well with those determined independently by various authors for stars in common. Their data show that mass loss rates increase with luminosity and are a decreasing function of surface gravity. (Auth.)

  20. Reducing Nursing Student Attrition: The Search for Effective Strategies

    Science.gov (United States)

    Kubec, Cathy

    2017-01-01

    This review of the literature summarizes recent exploration of nursing student attrition. Attrition places financial burdens on students who leave a program, results in lost revenue for the college, and compounds the existing nursing shortage. Some research investigated the student selection process, which seeks to decrease attrition by admitting…

  1. Exploring Beginning Teachers' Attrition in the Netherlands

    Science.gov (United States)

    den Brok, Perry; Wubbels, Theo; van Tartwijk, Jan

    2017-01-01

    Based on a review of recent studies and reports, this research investigates attrition among beginning teachers in the Netherlands as well as reasons for teacher attrition, and compares the finding with studies on this topic conducted elsewhere in the world. The findings suggest that attrition among beginning teachers in the Netherlands with a…

  2. Observing the tabarru' rate in a family takaful

    Science.gov (United States)

    Ismail, Hamizun bin

    2013-04-01

    Takaful system has a built-in mechanism to counter any over-pricing policies of the insurance companies because whatever may be the premium charged, the surplus would normally go back to the participants in proportion to their contributions. In contrast to a conventional insurance company, insurance surplus is not supposed to be a source of return for a takaful company. Any surplus that is a result of overpricing or over-charging is required to be returned back to takaful participants. Similarly, in case of under-pricing, policyholders may be asked to meet any deficit or negative difference between the policyholders' contribution and the actual claims, benefits and compensation. The objective of this study is to measure the efficacy of a family takaful contract through a simple actuarial model based on deterministic survival assumption. In addition, a linear tabarru' rate is introduced. The results show that the linear assumption on the tabarru' rate has an advantage over the flat rate as far as the risk of the prospective loss is concerned.

  3. Exchange rate behavior with negative interest rates: Some early negative observations

    OpenAIRE

    Hameed, Allaudeen S.; Rose, Andrew

    2017-01-01

    This paper examines exchange rate behavior during the recent period with negative nominal interest rates. We use a daily panel of data on 61 currencies from January 2010 through May 2016, during which five economies - Denmark, the European Economic and Monetary Union, Japan, Sweden, and Switzerland - experienced negative nominal interest rates. We examine both effective exchange rates and bilateral rates; the latter typically measured against the Swiss franc since Switzerland has had the long...

  4. Observing relationships in Finnish adoptive families: Oulu Family Rating Scale.

    Science.gov (United States)

    Tienari, Pekka; Wynne, Lyman C; Sorri, Anneli; Lahti, Ilpo; Moring, Juha; Nieminen, Pentti; Joukamaa, Matti; Naarala, Mikko; Seitamaa, Markku; Wahlberg, Karl-Erik; Miettunen, Jouko

    2005-01-01

    Adoption studies were intended to separate genetic from environmental "causal" factors. In earlier adoption studies, psychiatric diagnostic labels for the adoptive parents were used as a proxy for the multiple dimensions of the family rearing environment. In the Finnish Adoption Study, research design provided the opportunity to study directly the adoptive family rearing environment. For this purpose 33 sub-scales were selected creating what we call Oulu Family Rating Scale (OPAS, Oulun PerheArviointiSkaala). In this paper, the manual for scoring of these sub-scales is presented.

  5. Issues concerning recruitment, retention and attrition of student nurses in the 1950/60s: a comparative study.

    Science.gov (United States)

    Jinks, Annette M; Richardson, Kathleen; Jones, Chris; Kirton, Jennifer A

    2014-11-01

    To investigate student nurse recruitment and attrition in the 1950' and 1960s and undertake comparisons to modern day concerns. The study was set in one hospital in the U.K. In the period studied nursing was unpopular as a profession and there were difficulties surrounding recruitment. Attrition rates were high. Documentary analysis of 641 training records dating 1955 to 1968 was undertaken. Attrition rates, reasons for non-completion and employment following successful completion were determined. Most recruits were young, unmarried, females and had overseas addresses. The majority (n = 88) had prior nursing experience. Over 69% (n = 443) successfully completed their training. Attrition rates were over 30% (n = 198), the main reason being academic failure. Following completion over 40% (n = 183) undertook midwifery training (n = 183) or secured a staff nurse post (n = 153). Issues relating to recruitment, retention and attrition in the 1950s and 1960s put into context present day issues. Recent attrition rates from pre-registration nurse education have fallen, nevertheless some of the issues of yesteryear remain problematic. In the present study significant numbers of entrants left due to domestic and ill-health problems resonates with many modern day studies. Also failure to complete due to academic shortcomings continues to be a concern. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Attrition resistant gamma-alumina catalyst support

    Science.gov (United States)

    Singleton, Alan H.; Oukaci, Rachid; Goodwin, James G.

    2006-03-14

    A .gamma.-alumina catalyst support having improved attrition resistance produced by a method comprising the steps of treating a particulate .gamma.-alumina material with an acidic aqueous solution comprising water and nitric acid and then, prior to adding any catalytic material thereto, calcining the treated .gamma.-alumina.

  7. Predicting Student Attrition with Data Mining Methods

    Science.gov (United States)

    Delen, Dursun

    2012-01-01

    Affecting university rankings, school reputation, and financial well-being, student retention has become one of the most important measures of success for higher education institutions. From the institutional perspective, improving student retention starts with a thorough understanding of the causes behind the attrition. Such an understanding is…

  8. Does a Teacher's Classroom Observation Rating Vary across Multiple Classrooms?

    Science.gov (United States)

    Lei, Xiaoxuan; Li, Hongli; Leroux, Audrey J.

    2018-01-01

    Classroom observations have been increasingly used for teacher evaluations, and it is important to examine the measurement quality and the use of observation ratings. When a teacher is observed in multiple classrooms, his or her observation ratings may vary across classrooms. In that case, using ratings from one classroom per teacher may not be…

  9. Examining the Relationship Between Mental, Physical, and Organizational Factors Associated With Attrition During Maritime Forces Training.

    Science.gov (United States)

    Binsch, Olaf; Banko, Katherine M; Veenstra, Bertil J; Valk, Pierre J L

    2015-11-01

    For infantry units of the Dutch Ministry of Defence, high attrition rates (varying from 42 to 68%) during initial training are a persisting problem. The reasons for this attrition are diverse. Having better insight into the causes of attrition is a prerequisite for implementing preventive measures. To achieve this, a monitoring assessment system was developed that integrated the effects of physical, mental, and organizational determinants on operational readiness. The aim of this study was to implement the monitoring tools and to establish the set of determinants that best predicted attrition during infantry training of new recruits. Eighty-five recruits were monitored over a 24-week infantry training course. Before the training, recruits were screened for medical, psychological, and physical wellness. During the monitoring phase, mental, physiological, and organizational indicants were obtained using an array of tools such as questionnaires, chest belt monitors (for heart rate, acceleration, and skin temperature measurements), and computerized tests (e.g., vigilance, long-term memory). Survival analyses were used to tease out the determinants of individual and grouped predictors of attrition. Nearly half the recruits (47%) failed the training. Attrition was predicted by both physiological and mental determinants. However, the organizational determinant "trainers' judgment" on the "recruits' military quality" dominated the physiological and mental determinants. It was concluded that the monitoring system was successfully implemented during infantry training, and that the survival analysis method emphasized on single effects and interactions between the different determinants. Based on the current findings, we recommend several steps to successfully implement a monitoring method in settings with high demands.

  10. Vocabulary Attrition among Adult English as a Foreign Language Persian Learners

    Science.gov (United States)

    Asgari, Azadeh; Bin Mustapha, Ghazali

    2010-01-01

    This study aims to investigate the attrition rate of EFL concrete and abstract vocabulary among continuing and non-continuing Iranian female and male English language learners across different proficiency levels. They are students of a University and majored in different fields (between 20 and 25 years old). There was no treatment in this study…

  11. Special Education Teacher Perception of Administrative Supports That Encourage, Decrease Burnout, and Reduce Attrition

    Science.gov (United States)

    Beebe, Jay

    2017-01-01

    The field of special education is facing a shortage of teachers. A shortage of special education teachers is an example of a pressing issue within education. The problem is that teacher attrition rates are among the highest within special education. Many special education teachers are leaving the profession after a few years of teaching for varied…

  12. Self-rated and observer-rated measures of well-being and distress in adolescence: an exploratory study.

    Science.gov (United States)

    Vescovelli, Francesca; Albieri, Elisa; Ruini, Chiara

    2014-01-01

    The evaluation of eudaimonic well-being in adolescence is hampered by the lack of specific assessment tools. Moreover, with younger populations, the assessment of positive functioning may be biased by self-report data only, and may be more accurate by adding significant adults' evaluations. The objective of this research was to measure adolescents' well-being and prosocial behaviours using self-rated and observer-rated instruments, and their pattern of associations. The sample included 150 Italian high school adolescents. Observed-evaluation was performed by their school teachers using the Strengths and Difficulties Questionnaire. Adolescents completed Ryff's Psychological Well-being Scales and Symptom Questionnaire. Pearson' r correlations and Linear regression were performed. Self-rated dimensions of psychological well-being significantly correlated with all observer-rated dimensions, but Strengths and Difficulties Emotional symptom scale. Multiple linear regression showed that the self-rated dimensions Environmental Mastery and Personal Growth, and surprisingly not Positive Relations, are related to the observer-rated dimension Prosocial Behaviour. Adolescents with higher levels of well-being in specific dimensions tend to be perceived as less problematic by their teachers. However, some dimensions of positive functioning present discrepancies between self and observer-rated instruments. Thus, the conjunct use of self-reports and observer-rated tools for a more comprehensive assessment of students' eudaimonic well-being is recommended.

  13. Reliability and Cost Impacts for Attritable Systems

    Science.gov (United States)

    2017-03-23

    on reliability and cost: a probabilistic model. Electric Power Systems Research, 72(3), 213-224. Kalbfleisch, J.D. & Prentice, R.L. (1980). The...copyright protection in the United States. AFIT-ENV-MS-17-M-172 RELIABILITY AND COST IMPACTS FOR ATTRITABLE SYSTEMS THESIS Presented to... power of discrete time Markov chains, whether homogeneous or non-homogeneous, to model the reliability and dependability of repairable systems should

  14. Analytical modelling for ultrasonic surface mechanical attrition treatment

    Directory of Open Access Journals (Sweden)

    Guan-Rong Huang

    2015-07-01

    Full Text Available The grain refinement, gradient structure, fatigue limit, hardness, and tensile strength of metallic materials can be effectively enhanced by ultrasonic surface mechanical attrition treatment (SMAT, however, never before has SMAT been treated with rigorous analytical modelling such as the connection among the input energy and power and resultant temperature of metallic materials subjected to SMAT. Therefore, a systematic SMAT model is actually needed. In this article, we have calculated the averaged speed, duration time of a cycle, kinetic energy and kinetic energy loss of flying balls in SMAT for structural metallic materials. The connection among the quantities such as the frequency and amplitude of attrition ultrasonic vibration motor, the diameter, mass and density of balls, the sample mass, and the height of chamber have been considered and modelled in details. And we have introduced the one-dimensional heat equation with heat source within uniform-distributed depth in estimating the temperature distribution and heat energy of sample. In this approach, there exists a condition for the frequency of flying balls reaching a steady speed. With these known quantities, we can estimate the strain rate, hardness, and grain size of sample.

  15. The Surgical Personality: Does Surgery Resident Motivation Predict Attrition?

    Science.gov (United States)

    Symer, Matthew M; Abelson, Jonathan S; Yeo, Heather L; Sosa, Julie A; Rosenthal, M Zachary

    2018-05-01

    There is limited understanding of the wide variation in attrition rates among general surgery residencies. We used the validated Behavior Inhibitory System/Behavior Approach System (BIS/BAS) instrument to compare motivational traits among residents who did and not complete surgical training. All US general surgery categorical interns in the class of 2007-2008 were surveyed with a validated motivational trait assessment tool. American Board of Surgery records from 2008-2016 were used to determine who completed training. Motivation, an aspect of personality, was assessed with the BIS/BAS, which correlates with an individual's tendency to approach pleasant stimuli (BAS) or avoid negative stimuli (BIS). Subscale mean scores were compared with regard to the primary end point, attrition. Eight hundred and one (76.5%) interns completed the survey and had matching records. Six hundred and forty-five (80.5%) completed training. Men had lower scores than women in the BAS Drive subscale (12.0 vs 12.5; p scale (19.3 vs 20.9; p academic 17.3 vs community 17.6 vs military 16.6; p motivational personality traits. Copyright © 2018 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

  16. Expectations and voluntary attrition in nursing students.

    Science.gov (United States)

    O'Donnell, Hugh

    2011-01-01

    This paper presents a series of findings generated during a larger study which aimed to develop a theoretical understanding of the reasons why nursing students voluntarily leave pre-registration nursing programmes. In this study, significant incongruence was found to exist between student expectations of pre-registration nursing programmes and the reality of these programmes following entry. The resulting dissonance was identified as an important factor in student decisions to voluntarily withdraw. A single case study design was selected to explore the causes of voluntary attrition in nursing students within a School of Nursing and Midwifery. The study population was obtained through purposeful sampling and consisted of 15 students who had previously voluntarily withdrawn from pre-registration nursing programmes. A semi-structured interview method was used to collect data from study participants. The interview schedule developed for use in the study reflected the key components of the conceptual model of higher education (HE) student attrition (Tinto, 1975, 1987, 1993). All interviews were tape recorded to facilitate later transcription. The Cyclical or Interactive Model of Qualitative Research (Miles and Huberman, 1994) was used to analyse data collected from study participants. This paper describes the unrealistic range of expectations which nursing students have of nursing, the information sources and experiences which inform student expectations and how ambiguous expectations contributed to voluntarily attrition. Copyright © 2010 Elsevier Ltd. All rights reserved.

  17. Factors related to attrition from trauma-focused cognitive behavioral therapy.

    Science.gov (United States)

    Wamser-Nanney, Rachel; Steinzor, Cazzie E

    2017-04-01

    Attrition from child trauma-focused treatments such as Trauma-Focused Cognitive Behavioral Therapy (TF-CBT) is common; yet, the factors of children who prematurely terminate are unknown. The aim of the current study was to identify risk factors for attrition from TF-CBT. One hundred and twenty-two children (ages 3-18; M=9.97, SD=3.56; 67.2% females; 50.8% Caucasian) who received TF-CBT were included in the study. Demographic and family variables, characteristics of the trauma, and caregiver- and child-reported pretreatment symptoms levels were assessed in relation to two operational definitions of attrition: 1) clinician-rated dropout, and 2) whether the child received an adequate dose of treatment (i.e., 12 or more sessions). Several demographic factors, number of traumatic events, and children's caregiver-rated pretreatment symptoms were related to clinician-rated dropout. Fewer factors were associated with the adequate dose definition. Child Protective Services involvement, complex trauma exposure, and child-reported pretreatment trauma symptoms were unrelated to either attrition definition. Demographics, trauma characteristics, and level of caregiver-reported symptoms may help to identify clients at risk for premature termination from TF-CBT. Clinical and research implications for different operational definitions and suggestions for future work will be presented. Published by Elsevier Ltd.

  18. Demographic and psychological predictors of panel attrition: evidence from the New Zealand attitudes and values study.

    Directory of Open Access Journals (Sweden)

    Nicole Satherley

    Full Text Available This study examines attrition rates over the first four years of the New Zealand Attitudes and Values Study, a longitudinal national panel sample of New Zealand adults. We report the base rate and covariates for the following four distinct classes of respondents: explicit withdrawals, lost respondents, intermittent respondents and constant respondents. A multinomial logistic regression examined an extensive range of demographic and socio-psychological covariates (among them the Big-Six personality traits associated with membership in these classes (N = 5,814. Results indicated that men, Māori and Asian peoples were less likely to be constant respondents. Conscientiousness and Honesty-Humility were also positively associated with membership in the constant respondent class. Notably, the effect sizes for the socio-psychological covariates of panel attrition tended to match or exceed those of standard demographic covariates. This investigation broadens the focus of research on panel attrition beyond demographics by including a comprehensive set of socio-psychological covariates. Our findings show that core psychological covariates convey important information about panel attrition, and are practically important to the management of longitudinal panel samples like the New Zealand Attitudes and Values Study.

  19. The management of over closured anterior teeth due to attrition

    OpenAIRE

    Eha Djulaeha; Sukaedi Sukaedi

    2009-01-01

    Background: Tooth is the hardest tissue in human body, that can be injured because of attrition process. For old people, denture attrition process is caused by psysiological process relating with the mastication function which also supported by some bad habits such an bruxism, premature contact, and consuming habit of abrasive food. Attrition or abrasion can also be happened with patien’t dentition who does not have teeth subtutition for long time due the lost of their maxillary as well as ma...

  20. Factors affecting attrition from associate degree nursing programs in North Carolina.

    Science.gov (United States)

    Fraher, Erin; Belsky, Daniel W; Gaul, Katie; Carpenter, Jessica

    2010-01-01

    Projected nursing shortfalls have spurred the state of North Carolina to initiate a series of strategies to increase the number of graduates from pre-licensure Registered Nurse (RN) programs. These efforts have been largely successful, but attrition rates from Associate Degree Nursing (ADN) programs remain high. Only 58% of students entering ADN programs complete the degree. While policy makers are keenly aware that attrition from ADN programs is problematic, there is a lack of empirical evidence to identify the specific factors contributing to student attrition. In late 2007, the North Carolina Community College System (NCCCS) asked the Cecil G. Sheps Center for Health Services Research to conduct a study of Associate Degree Nursing program attrition and its causes. This paper summarizes the findings from that study and identifies the student- and program-level characteristics associated with more and less successful ADN programs. While this study was conducted in a single state in the US, the substantive findings--as well as the methodological approach--may be useful to other states and other countries. The study revealed that socioeconomically disadvantaged students (those with GEDs and those who received Pell Grants), non-white students, and younger and older students were less likely to graduate on-time. When programs were grouped into high and low performance categories on the basis of risk adjusted graduation rates, high performing programs were distinguished by more stringent admissions policies and better educated faculties. Nursing shortages have garnered significant attention and resources from state and national workforce planners in recent years. But to date, investments in expanding program capacity have not been matched by attention to program completion rates, with the result that we have enlarged the pipeline without fixing the leaks. Faculty shortages and recession-induced resource constraints limit further program expansion. Addressing attrition

  1. Dutch courage? Effects of acute alcohol consumption on self-ratings and observer ratings of foreign language skills.

    Science.gov (United States)

    Renner, Fritz; Kersbergen, Inge; Field, Matt; Werthmann, Jessica

    2018-01-01

    A popular belief is that alcohol improves the ability to speak in a foreign language. The effect of acute alcohol consumption on perceived foreign language performance and actual foreign language performance in foreign language learners has not been investigated. The aim of the current study was to test the effects of acute alcohol consumption on self-rated and observer-rated verbal foreign language performance in participants who have recently learned this language. Fifty native German speakers who had recently learned Dutch were randomized to receive either a low dose of alcohol or a control beverage that contained no alcohol. Following the experimental manipulation, participants took part in a standardized discussion in Dutch with a blinded experimenter. The discussion was audio-recorded and foreign language skills were subsequently rated by two native Dutch speakers who were blind to the experimental condition (observer-rating). Participants also rated their own individual Dutch language skills during the discussion (self-rating). Participants who consumed alcohol had significantly better observer-ratings for their Dutch language, specifically better pronunciation, compared with those who did not consume alcohol. However, alcohol had no effect on self-ratings of Dutch language skills. Acute alcohol consumption may have beneficial effects on the pronunciation of a foreign language in people who have recently learned that language.

  2. Survey on workforce retention and attrition

    Science.gov (United States)

    Showstack, Randy

    2013-03-01

    The Society of Petroleum Engineers (SPE) is conducting a survey to gather information on why technical professionals change jobs or quit working. The survey, prompted by concern about the retention of skilled workers, aims to provide information to employers that can assist them in addressing practices that can lead to significant workforce attrition. To participate in the survey, which is open to everyone (including those who are not SPE members), go to http://research.spe.org/se.ashx?s=705E3F1335720258 through 15 May 2013. For more information, contact speresearch@spe.org.

  3. The Rapier or the Club: The Relationship between Attrition and Maneuver Warfare

    National Research Council Canada - National Science Library

    Springman, Jeffrey A

    2006-01-01

    ...? This project compares the relationship between attrition and maneuver warfare. The study considers whether there are times when wars of attrition should be fought, and whether there are conditions that force wars of attrition...

  4. The influence of temperature on limestone sulfation and attrition under fluidized bed combustion conditions

    Energy Technology Data Exchange (ETDEWEB)

    Montagnaro, Fabio [Dipartimento di Chimica - Universita degli Studi di Napoli Federico II, Complesso Universitario del Monte di Sant' Angelo, 80126 Napoli (Italy); Salatino, Piero [Istituto di Ricerche sulla Combustione - CNR, Piazzale Vincenzo Tecchio 80, 80125 Napoli (Italy); Dipartimento di Ingegneria Chimica - Universita degli Studi di Napoli Federico II, Piazzale Vincenzo Tecchio 80, 80125 Napoli (Italy); Scala, Fabrizio [Istituto di Ricerche sulla Combustione - CNR, Piazzale Vincenzo Tecchio 80, 80125 Napoli (Italy)

    2010-04-15

    The influence of temperature on attrition of two limestones during desulfurization in a fluidized bed reactor was investigated. Differences in the microstructure of the two limestones were reflected by a different thickness of the sulfate shell formed upon sulfation and by a different value of the ultimate calcium conversion degree. Particle attrition and fragmentation were fairly small under moderately bubbling fluidization conditions for both limestones. An increase of temperature from 850 C to 900 C led to an increase of the attrition rate, most likely because of a particle weakening effect caused by a faster CO{sub 2} evolution during calcination. This weakening effect, however, was not sufficiently strong to enhance particle fragmentation in the bed. The progress of sulfation, associated to the build-up of a hard sulfate shell around the particles, led in any case to a decrease of the extent of attrition. Sulfation at 900 C was less effective than at 850 C, and this was shown to be related to the porosimetric features of the different samples. (author)

  5. Attrition from surgical residency training: perspectives from those who left.

    Science.gov (United States)

    Bongiovanni, Tasce; Yeo, Heather; Sosa, Julie A; Yoo, Peter S; Long, Theodore; Rosenthal, Marjorie; Berg, David; Curry, Leslie; Nunez-Smith, Marcella

    2015-10-01

    High rates of attrition from general surgery residency may threaten the surgical workforce. We sought to gain further insight regarding resident motivations for leaving general surgery residency. We conducted in-depth interviews to generate rich narrative data that explored individual experiences. An interdisciplinary team used the constant comparative method to analyze the data. Four themes characterized experiences of our 19 interviewees who left their residency program. Participants (1) felt an informal contract was breached when clinical duties were prioritized over education, (2) characterized a culture in which there was no safe space to share personal and programmatic concerns, (3) expressed a scarcity of role models who demonstrated better work-life balance, and (4) reported negative interactions with authority resulting in a profound loss of commitment. As general surgery graduate education continues to evolve, our findings may inform interventions and policies regarding programmatic changes to boost retention in surgical residency. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Does Coordinated, Multidisciplinary Treatment Limit Medical Disability and Attrition Related to Spine Conditions in the US Navy?

    Science.gov (United States)

    Ziemke, Gregg; Campello, Marco; Hiebert, Rudi; Weiner, Shira Schecter; Rennix, Chris; Nordin, Margareta

    2015-09-01

    implemented in 2008. The risk of disability was lower at Naval Medical Center Portsmouth as compared with Naval Medical Center San Diego for each of the 3 years studied (in 2007, the relative risk was 0.53 [95% confidence limit {CL}, 0.42-0.68; p Team at Naval Medical Center Portsmouth. There were no differences observed in rates of attrition from the period before the introduction of the Spine Team to after at Naval Medical Center Portsmouth, and no overall differences could be statistically detected between the two sites. This study provides suggestive evidence that a multi-disciplinary Spine Team may be effective in limiting disability. No conclusion can be drawn about the Spine Team's effectiveness in limiting attrition. Additional study is warranted to examine the effect of the timing of the introduction of multidisciplinary care for work-disabling spine conditions. Level III, therapeutic study.

  7. Attrition resistant Fischer-Tropsch catalyst and support

    Science.gov (United States)

    Singleton, Alan H.; Oukaci, Rachid; Goodwin, James G.

    2004-05-25

    A catalyst support having improved attrition resistance and a catalyst produced therefrom. The catalyst support is produced by a method comprising the step of treating calcined .gamma.-alumina having no catalytic material added thereto with an acidic aqueous solution having an acidity level effective for increasing the attrition resistance of the calcined .gamma.-alumina.

  8. Early Career Teacher Attrition: Intentions of Teachers Beginning

    Science.gov (United States)

    Clandinin, D. Jean; Long, Julie; Schaefer, Lee; Downey, C. Aiden; Steeves, Pam; Pinnegar, Eliza; McKenzie Robblee, Sue; Wnuk, Sheri

    2015-01-01

    Early career teacher attrition has most often been conceptualized as either a problem associated with individual factors (e.g. burnout) or a problem associated with contextual factors (e.g. support and salary). This study considered early career teacher attrition as an identity making process that involves a complex negotiation between individual…

  9. Obstacles to Success--Doctoral Student Attrition in South Africa

    Science.gov (United States)

    Herman, Chaya

    2011-01-01

    The article explores doctoral attrition in South Africa, investigating and comparing the attributions of attrition of doctoral students and PhD programme leaders. The article is based on secondary data analysis of two large studies on doctoral education in South Africa. The main point of the article is that the different understandings of the…

  10. Web-Based Alcohol Intervention: Study of Systematic Attrition of Heavy Drinkers.

    Science.gov (United States)

    Radtke, Theda; Ostergaard, Mathias; Cooke, Richard; Scholz, Urte

    2017-06-28

    Web-based alcohol interventions are a promising way to reduce alcohol consumption because of their anonymity and the possibility of reaching a high numbers of individuals including heavy drinkers. However, Web-based interventions are often characterized by high rates of attrition. To date, very few studies have investigated whether individuals with higher alcohol consumption show higher attrition rates in Web-based alcohol interventions as compared with individuals with lower alcohol consumption. The aim of this study was to examine the attrition rate and predictors of attrition in a Web-based intervention study on alcohol consumption. The analysis of the predictors of attrition rate was performed on data collected in a Web-based randomized control trial. Data collection took place at the University of Konstanz, Germany. A total of 898 people, which consisted of 46.8% males (420/898) and 53.2% females (478/898) with a mean age of 23.57 years (SD 5.19), initially volunteered to participate in a Web-based intervention study to reduce alcohol consumption. Out of the sample, 86.9% (781/898) were students. Participants were classified as non-completers (439/898, 48.9%) if they did not complete the Web-based intervention. Potential predictors of attrition were self-reported: alcohol consumption in the last seven days, per week, from Monday to Thursday, on weekends, excessive drinking behavior measured with the Alcohol Use Disorder Identification Test (AUDIT), and drinking motives measured by the Drinking Motive Questionnaire (DMQ-R SF). Significant differences between completers and non-completers emerged regarding alcohol consumption in the last seven days (B=-.02, P=.05, 95% CI [0.97-1.00]), on weekends (B=-.05, P=.003, 95% CI [0.92-0.98]), the AUDIT (B=-.06, P=.007, 95% CI [0.90-0.98], and the status as a student (B=.72, P=.001, 95% CI [1.35-3.11]). Most importantly, non-completers had a significantly higher alcohol consumption compared with completers. Hazardous

  11. The pattern of attrition from an antiretroviral treatment program in Nigeria.

    Directory of Open Access Journals (Sweden)

    Solomon Odafe

    Full Text Available To evaluate the rate and factors associated with attrition of patients receiving ART in tertiary and secondary hospitals in Nigeria.We reviewed patient level data collected between 2007 and 2010 from 11 hospitals across Nigeria. Kaplan-Meier product-limit and Cox regression were used to determine probability of retention in care and risk factors for attrition respectively. Of 6,408 patients in the cohort, 3,839 (59.9% were females, median age of study population was 33years (IQR: 27-40 and 4,415 (69% were from secondary health facilities. The NRTI backbone was Stavudine (D4T in 3708 (57.9% and Zidovudine (ZDV in 2613 (40.8% of patients. Patients lost to follow up accounted for 62.7% of all attrition followed by treatment stops (25.3% and deaths (12.0%. Attrition was 14.1 (N = 624 and 15.1% (N = 300 in secondary and tertiary hospitals respectively (p = 0.169 in the first 12 months on follow up. During the 13 to 24 months follow up period, attrition was 10.7% (N = 407 and 19.6% (N = 332 in secondary and tertiary facilities respectively (p<0.001. Median time to lost to follow up was 11.1 (IQR: 6.1 to 18.5 months in secondary compared with 13.6 (IQR: 9.9 to 17.0 months in tertiary sites (p = 0.002. At 24 months follow up, male gender [AHR 1.18, 95% CI: 1.01-1.37, P = 0.038]; WHO clinical stage III [AHR 1.30, 95%CI: 1.03-1.66, P = 0.03] and clinical stage IV [AHR 1.90, 95%CI: 1.20-3.02, p = 0.007] and care in a tertiary hospital [AHR 2.21, 95% CI: 1.83-2.67, p<0.001], were associated with attrition.Attrition could potentially be reduced by decentralizing patients on ART after the first 12 months on therapy to lower level facilities, earlier initiation on treatment and strengthening adherence counseling amongst males.

  12. Limestone fragmentation and attrition during fluidized bed oxyfiring

    Energy Technology Data Exchange (ETDEWEB)

    Fabrizio Scala; Piero Salatino [Istituto di Ricerche sulla Combustione - CNR, Napoli (Italy)

    2010-04-15

    Attrition/fragmentation of limestone under simulated fluidized bed oxyfiring conditions was investigated by means of an experimental protocol that had been previously developed for characterization of attrition/fragmentation of sorbents in air-blown atmospheric fluidized bed combustors. The protocol was based on the use of different and mutually complementary techniques. The extent and pattern of attrition by surface wear in the dense phase of a fluidized bed were assessed in experiments carried out with a bench scale fluidized bed combustor under simulated oxyfiring conditions. Sorbent samples generated during simulated oxyfiring tests were further characterized from the standpoint of fragmentation upon high velocity impact by means of a purposely designed particle impactor. Results showed that under calcination-hindered conditions attrition and fragmentation patterns are much different from those occurring under air-blown atmospheric combustion conditions. Noteworthy, attrition/fragmentation enhanced particle sulfation by continuously regenerating the exposed particle surface. 13 refs., 8 figs.

  13. Limestone attrition under simulated oxyfiring Fluidized-Bed combustion conditions

    Energy Technology Data Exchange (ETDEWEB)

    Scala, F. [Istituto di Ricerche sulla Combustione - CNR, Napoli (Italy); Salatino, P. [Dipartimento di Ingegneria Chimica - Universita degli Studi di Napoli Federico II, Napoli (Italy)

    2009-03-15

    Limestone attrition by surface wear was studied during the flue gas desulfurization under simulated fluidized-bed (FB) oxyfiring conditions and hindered calcination. Bench-scale experimental tests were carried out using well-established techniques previously developed for the characterization of sulfation and attrition of sorbents in air-blown atmospheric FB combustors. The experimental limestone conversion and attrition results were compared with those previously obtained with the same limestone under simulated air-blown combustion conditions. The differences in the conversion and attrition extents and patterns associated with oxyfiring as compared to air-blown atmospheric combustion were highlighted and related to the different particle morphologies and thicknesses of the sulfate layer. It was noted that attrition could play an important role in practical circulating FB combustor operation, by effectively enhancing particle sulfation under both oxyfiring and air-blown combustion conditions. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  14. [Attrition and poor performance in general practice training: age, competence and knowledge play a role].

    Science.gov (United States)

    Vermeulen, Margit I; Kuyvenhoven, Marijke M; Zuithoff, N P A Peter; van der Graaf, Yolanda; Pieters, H M Ron

    2011-01-01

    To investigate which determinants are related to poor performance and forced attrition in the first year residency in general practice (GP). Observational retrospective cohort study. We collected data relating to personal characteristics such as age, sex and clinical experience from residents who started the GP training in Utrecht, the Netherlands, in the period March 2005-August 2007. We also collected competence scores from the domains 'medical expertise', 'doctor-patient communication' and 'professionalism', as well as scores on a national GP knowledge test. The outcome measures were 'poor performance' and 'forced attrition'. Multivariate logistic regression was used to analyse correlations between personal characteristics, competence scores on the 3 domains and knowledge scores in the first trimester on the one hand and poor performance or forced attrition on the other. 215 residents started the GP training. In the first trimester a quarter of the residents had an insufficient score in 1 or more of the domains. Competence scores were mutually correlated, but did not correlate with the knowledge score. 18 residents showed poor performance and 3 were forced to stop their training. Poor performance and forced attrition were correlated with age (adjusted odds ratio (OR): 1.1; 95% CI: 1.0-1.3), insufficient knowledge (adjusted OR: 8.9; 3.0-26.3) and medical expertise (adjusted OR: 2.1; 1.1-4.0) at the beginning of the training. Age, insufficient knowledge of general practice, and insufficient competence in the domain of 'medical expertise' at the beginning of the training are risk factors for poor performance by residents and attrition from their GP training.

  15. Attrition of schistosomes in an irradiation-attenuated cercarial immunization model of Schistosoma mansoni

    International Nuclear Information System (INIS)

    Stek, M. Jr.; Dean, D.A.; Clark, S.S.

    1981-01-01

    The attrition of Schistosoma mansoni challenge worms was studied in irradiation-attenuated cercaria-immunized mice as a function of site and time. The peak recovery of schistosomula from the lungs of immunized mice was delayed 2 days in comparison with non-immunized controls. The difference between the peak recoveries of control and immunized mice accounted for about half of the final attrition observed at the 7-week adult worm stge. Hepatic-mesenteric vein worm recoveries obtained 10 to 42 days after challenge were reduced in most cases at least as much as the 49-day counts. Somewhat higher reductions were observed at 14 to 28 days than at 49 days, confirming the evidence of delayed migration obtained at the lung phase. These findings, coupled with histologic observations, indicate that at least half of the worm elimination attributable to immunization occurs 8 or more days after the challenge infection

  16. Predicting Active Duty Air Force Pilot Attrition Given an Anticipated Increase in Major Airline Pilot Hiring

    Science.gov (United States)

    2015-01-01

    the Air Force in addressing some quality-of-life issues, such as updating 3,800 family housing units, 21 dormitories, and building three child ...of pilots into the airlines (Air Force Personnel Center, FY 07). By allowing this crop of pilots to leave on the Air Force’s terms, the service felt...attrition rates compared with pilots with more general skills (flying mobility aircraft) (Stephen P. Barrows, 1993). This may be due to the phenomenon in

  17. New England observed and predicted August stream/river temperature maximum daily rate of change points

    Data.gov (United States)

    U.S. Environmental Protection Agency — The shapefile contains points with associated observed and predicted August stream/river temperature maximum negative rate of change in New England based on a...

  18. Influence of attrition variables on iron ore flotation

    Directory of Open Access Journals (Sweden)

    Fabiana Fonseca Fortes

    Full Text Available Abstract The presence of slimes is harmful to the flotation process: the performance and consumption of reagents are negatively affected. Traditionally, the desliming stage has been responsible for removing slimes. However, depending on the porosity of the mineral particles, desliming may not be sufficient to maximize the concentration results. An attrition process before the desliming operation can improve the removal of slime, especially when slimes cover the surface and/or are confined to the cavities/pores of the mineral particles. Attrition is present in the flowcharts of the beneficiation process of phosphate and industrial sand (silica sand. Research has been undertaken for its application to produce pre-concentrates of zircon and iron ore. However, there is still little knowledge of the influence of the attrition variables on the beneficiation process of iron ore. This study presents a factorial design and analysis of the effects of these variables on the reverse flotation of iron ore. The standard of the experimental procedures for all tests included the attrition of pulp, under the conditions of dispersion, desliming and flotation. The parameter analysed (variable response was the metallurgical recovery in reverse flotation tests. The planning and analysis of the full factorial experiment indicated that with 95% reliability, the rotation speed of the attrition cell impeller was the main variable in the attrition process of the iron ore. The percentage of solid variables in the pulp and the time of the attrition, as well as their interactions, were not indicated to be significant.

  19. Medical school attrition-beyond the statistics a ten year retrospective study.

    Science.gov (United States)

    Maher, Bridget M; Hynes, Helen; Sweeney, Catherine; Khashan, Ali S; O'Rourke, Margaret; Doran, Kieran; Harris, Anne; Flynn, Siun O'

    2013-01-31

    Medical school attrition is important--securing a place in medical school is difficult and a high attrition rate can affect the academic reputation of a medical school and staff morale. More important, however, are the personal consequences of dropout for the student. The aims of our study were to examine factors associated with attrition over a ten-year period (2001-2011) and to study the personal effects of dropout on individual students. The study included quantitative analysis of completed cohorts and qualitative analysis of ten-year data. Data were collected from individual student files, examination and admission records, exit interviews and staff interviews. Statistical analysis was carried out on five successive completed cohorts. Qualitative data from student files was transcribed and independently analysed by three authors. Data was coded and categorized and key themes were identified. Overall attrition rate was 5.7% (45/779) in 6 completed cohorts when students who transferred to other medical courses were excluded. Students from Kuwait and United Arab Emirates had the highest dropout rate (RR = 5.70, 95% Confidence Intervals 2.65 to 12.27;p psychological morbidity in 40% (higher than other studies). Qualitative analysis revealed recurrent themes of isolation, failure, and despair. Student Welfare services were only accessed by one-third of dropout students. While dropout is often multifactorial, certain red flag signals may alert us to risk of dropout including non-EU origin, academic struggling, absenteeism, social isolation, depression and leave of absence. Psychological morbidity amongst dropout students is high and Student Welfare services should be actively promoted. Absenteeism should prompt early intervention. Behind every dropout statistic lies a personal story. All medical schools have a duty of care to support students who leave the medical programme.

  20. Medical School Attrition-Beyond the Statistics A Ten Year Retrospective Study

    Directory of Open Access Journals (Sweden)

    Maher Bridget M

    2013-01-01

    Full Text Available Abstract Background Medical school attrition is important - securing a place in medical school is difficult and a high attrition rate can affect the academic reputation of a medical school and staff morale. More important, however, are the personal consequences of dropout for the student. The aims of our study were to examine factors associated with attrition over a ten-year period (2001–2011 and to study the personal effects of dropout on individual students. Methods The study included quantitative analysis of completed cohorts and qualitative analysis of ten-year data. Data were collected from individual student files, examination and admission records, exit interviews and staff interviews. Statistical analysis was carried out on five successive completed cohorts. Qualitative data from student files was transcribed and independently analysed by three authors. Data was coded and categorized and key themes were identified. Results Overall attrition rate was 5.7% (45/779 in 6 completed cohorts when students who transferred to other medical courses were excluded. Students from Kuwait and United Arab Emirates had the highest dropout rate (RR = 5.70, 95% Confidence Intervals 2.65 to 12.27;p  Absenteeism was documented in 30% of students, academic difficulty in 55.7%, social isolation in 20%, and psychological morbidity in 40% (higher than other studies. Qualitative analysis revealed recurrent themes of isolation, failure, and despair. Student Welfare services were only accessed by one-third of dropout students. Conclusions While dropout is often multifactorial, certain red flag signals may alert us to risk of dropout including non-EU origin, academic struggling, absenteeism, social isolation, depression and leave of absence. Psychological morbidity amongst dropout students is high and Student Welfare services should be actively promoted. Absenteeism should prompt early intervention. Behind every dropout statistic lies a personal story. All

  1. Increased effects of machining damage in beryllium observed at high strain rates

    International Nuclear Information System (INIS)

    Beitscher, S.; Brewer, A.W.; Corle, R.R.

    1980-01-01

    Tensile tests at both low and high strain rates, and also impact shear tests, were performed on a weldable grade powder-source beryllium. Impact energies increased by a factor of 2 to 3 from the as-machined level after etching or annealing. Similar increases in the ductility from machining damage removal were observed from the tensile data at the higher strain rate (10 s -1 ) while an insignificant increase in elongation was measured at the lower strain rate (10 -4 s -1 ). High strain-rate tests appear to be more sensitive and reliable for evaluating machining practice and damage removal methods for beryllium components subjected to sudden loads. 2 tables

  2. Treatment initiation, program attrition and patient treatment outcomes associated with scale-up and decentralization of HIV care in rural Malawi.

    Directory of Open Access Journals (Sweden)

    Megan McGuire

    Full Text Available OBJECTIVE: To describe patient antiretroviral therapy (cART outcomes associated with intensive decentralization of services in a rural HIV program in Malawi. METHODS: Longitudinal analysis of data from HIV-infected patients starting cART between August 2001 and December 2008 and of a cross-sectional immunovirological assessment conducted 12 (±2 months after therapy start. One-year mortality, lost to follow-up, and attrition (deaths and lost to follow-up rates were estimated with exact Poisson 95% confidence intervals (CI by type of care delivery and year of initiation. Association of virological suppression (<50 copies/mL and immunological success (CD4 gain ≥100 cells/µL, with type of care was investigated using multiple logistic regression. RESULTS: During the study period, 4322 cART patients received centralized care and 11,090 decentralized care. At therapy start, patients treated in decentralized health facilities had higher median CD4 count levels (167 vs. 130 cell/µL, P<0.0001 than other patients. Two years after cART start, program attrition was lower in decentralized than centralized facilities (9.9 per 100 person-years, 95% CI: 9.5-10.4 vs. 20.8 per 100 person-years, 95% CI: 19.7-22.0. One year after treatment start, differences in immunological success (adjusted OR=1.23, 95% CI: 0.83-1.83, and viral suppression (adjusted OR=0.80, 95% CI: 0.56-1.14 between patients followed at centralized and decentralized facilities were not statistically significant. CONCLUSIONS: In rural Malawi, 1- and 2-year program attrition was lower in decentralized than in centralized health facilities and no statistically significant differences in one-year immunovirological outcomes were observed between the two health care levels. Longer follow-up is needed to confirm these results.

  3. Influence of attrition scrubbing, ultrasonic treatment, and oxidant additions on uranium removal from contaminated soils

    International Nuclear Information System (INIS)

    Timpson, M.E.; Elless, M.P.; Francis, C.W.

    1994-01-01

    As part of the Uranium in Soils Integrated Demonstration Project being conducted by the US Department of Energy, bench-scale investigations of selective leaching of uranium from soils at the Fernald Environmental Management Project site in Ohio were conducted at Oak Ridge National Laboratory. Two soils (storage pad soil and incinerator soil), representing the major contaminant sources at the site, were extracted using carbonate- and citric acid-based lixiviants. Physical and chemical processes were used in combination with the two extractants to increase the rate of uranium release from these soils. Attrition scrubbing and ultrasonic dispersion were the two physical processes utilized. Potassium permanganate was used as an oxidizing agent to transform tetravalent uranium to the hexavalent state. Hexavalent uranium is easily complexed in solution by the carbonate radical. Attrition scrubbing increased the rate of uranium release from both soils when compared with rotary shaking. At equivalent extraction times and solids loadings, however, attrition scrubbing proved effective only on the incinerator soil. Ultrasonic treatments on the incinerator soil removed 71% of the uranium contamination in a single extraction. Multiple extractions of the same sample removed up to 90% of the uranium. Additions of potassium permanganate to the carbonate extractant resulted in significant changes in the extractability of uranium from the incinerator soil but had no effect on the storage pad soil

  4. A systematic review of satisfaction and pediatric obesity treatment: new avenues for addressing attrition.

    Science.gov (United States)

    Skelton, Joseph A; Irby, Megan Bennett; Geiger, Ann M

    2014-01-01

    Pediatric obesity treatment programs report high attrition rates, but it is unknown if family experience and satisfaction contributes. This review surveys the literature regarding satisfaction in pediatric obesity and questions used in measurement. A systematic review of the literature was conducted using Medline, PsychINFO, and CINAHL. Studies of satisfaction in pediatric weight management were reviewed, and related studies of obesity were included. Satisfaction survey questions were obtained from the articles or from the authors. Eighteen studies were included; 14 quantitative and 4 qualitative. Only one study linked satisfaction to attrition, and none investigated the association of satisfaction and weight outcomes. Most investigations included satisfaction as a secondary aim or used single-item questions of overall satisfaction; only one assessed satisfaction in noncompleters. Overall, participants expressed high levels of satisfaction with obesity treatment or prevention programs. Surveys focused predominantly on overall satisfaction or specific components of the program. Few in-depth studies of satisfaction with pediatric obesity treatment have been conducted. Increased focus on family satisfaction with obesity treatment may provide an avenue to lower attrition rates and improve outcomes. Enhancing measurement of satisfaction to yield actionable responses could positively influence outcomes, and a framework, via patient-centered care principles, is provided. © 2013 National Association for Healthcare Quality.

  5. Attitudes towards attrition among UK trainees in obstetrics and gynaecology.

    Science.gov (United States)

    Gafson, Irene; Currie, Jane; O'Dwyer, Sabrina; Woolf, Katherine; Griffin, Ann

    2017-06-02

    Physician dissatisfaction in the workplace has consequences for patient safety. Currently in the UK, 1 in 5 doctors who enter specialist training in obstetrics and gynaecology leave the programme before completion. Trainee attrition has implications for workforce planning, organization of health-care services and patient care. The authors conducted a survey of current trainees' and former trainees' views concerning attrition and 'peri-attrition' - a term coined to describe the trainee who has seriously considered leaving the specialty. The authors identified six key themes which describe trainees' feelings about attrition in obstetrics and gynaecology: morale and undermining; training processes and paperwork; support and supervision; work-life balance and realities of life; NHS environment; and job satisfaction. This article discusses themes of an under-resourced health service, bullying, lack of work-life balance and poor personal support.

  6. Could Realistic Job Previews Reduce First-Term Attrition

    National Research Council Canada - National Science Library

    Brose, Gary

    1999-01-01

    .... The military's use of educational screens, trends and costs of first-term attrition, and labor market theories of turnover are discussed to provide a common frame of reference within which to view...

  7. Averting the Train Wreck of Captain Attrition - A Leadership Solution

    National Research Council Canada - National Science Library

    Weafer, Thomas

    2001-01-01

    .... This paper looks at officer attrition in the context of a leadership challenge - it examines current perceived problems in leadership culture and command climate and recommends several changes focused on improving morale and retention of young officers.

  8. Discrepancies between self and observer ratings of depression. The relationship to demographic, clinical and personality variables.

    Science.gov (United States)

    Enns, M W; Larsen, D K; Cox, B J

    2000-10-01

    The observer-rated Hamilton depression scale (HamD) and the self-report Beck Depression Inventory (BDI) are among the most commonly used rating scales for depression, and both have well demonstrated reliability and validity. However, many depressed subjects have discrepant scores on these two assessment methods. The present study evaluated the ability of demographic, clinical and personality factors to account for the discrepancies observed between BDI and HamD ratings. The study group consisted of 94 SCID-diagnosed outpatients with a current major depressive disorder. Subjects were rated with the 21-item HamD and completed the BDI and the NEO-Five Factor Inventory. Younger age, higher educational attainment, and depressive subtype (atypical, non-melancholic) were predictive of higher BDI scores relative to HamD observer ratings. In addition, high neuroticism, low extraversion and low agreeableness were associated with higher endorsement of depressive symptoms on the BDI relative to the HamD. In general, these predictive variables showed a greater ability to explain discrepancies between self and observer ratings of psychological symptoms of depression compared to somatic symptoms of depression. The study does not determine which aspects of neuroticism and extraversion contribute to the observed BDI/HamD discrepancies. Depression ratings obtained with the BDI and HamD are frequently discordant and a number of patient characteristics robustly predict the discrepancy between these two rating methods. The value of multi-modal assessment in the conduct of research on depressive disorders is re-affirmed.

  9. Attitudes towards attrition among UK trainees in obstetrics and gynaecology

    OpenAIRE

    Gafson, I.; Currie, J.; O Dwyer, S.; Woolf, K.; Griffin, A.

    2017-01-01

    Physician dissatisfaction in the workplace has consequences for patient safety. Currently in the UK, 1 in 5 doctors who enter specialist training in obstetrics and gynaecology leave the programme before completion. Trainee attrition has implications for workforce planning, organization of health-care services and patient care. The authors conducted a survey of current trainees' and former trainees' views concerning attrition and ‘peri-attrition’ – a term coined to describe the trainee who has...

  10. Posttreatment attrition and its predictors, attrition bias, and treatment efficacy of the anxiety online programs.

    Science.gov (United States)

    Al-Asadi, Ali M; Klein, Britt; Meyer, Denny

    2014-10-14

    Although relatively new, the field of e-mental health is becoming more popular with more attention given to researching its various aspects. However, there are many areas that still need further research, especially identifying attrition predictors at various phases of assessment and treatment delivery. The present study identified the predictors of posttreatment assessment completers based on 24 pre- and posttreatment demographic and personal variables and 1 treatment variable, their impact on attrition bias, and the efficacy of the 5 fully automated self-help anxiety treatment programs for generalized anxiety disorder (GAD), social anxiety disorder (SAD), panic disorder with or without agoraphobia (PD/A), obsessive-compulsive disorder (OCD), and posttraumatic stress disorder (PTSD). A complex algorithm was used to diagnose participants' mental disorders based on the criteria of the Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition, Text Revision; DSM-IV-TR). Those who received a primary or secondary diagnosis of 1 of 5 anxiety disorders were offered an online 12-week disorder-specific treatment program. A total of 3199 individuals did not formally drop out of the 12-week treatment cycle, whereas 142 individuals formally dropped out. However, only 347 participants who completed their treatment cycle also completed the posttreatment assessment measures. Based on these measures, predictors of attrition were identified and attrition bias was examined. The efficacy of the 5 treatment programs was assessed based on anxiety-specific severity scores and 5 additional treatment outcome measures. On average, completers of posttreatment assessment measures were more likely to be seeking self-help online programs; have heard about the program from traditional media or from family and friends; were receiving mental health assistance; were more likely to learn best by reading, hearing and doing; had a lower pretreatment Kessler-6 total score; and were older

  11. ART Attrition across Health Facilities Implementing Option B+ in Haiti.

    Science.gov (United States)

    Myrtil, Martine Pamphile; Puttkammer, Nancy; Gloyd, Stephen; Robinson, Julia; Yuhas, Krista; Domercant, Jean Wysler; Honoré, Jean Guy; Francois, Kesner

    2018-01-01

    Describing factors related to high attrition is important in order to improve the implementation of the Option B+ strategy in Haiti. We conducted a retrospective cohort study to describe the variability of antiretroviral therapy (ART) retention across health facilities among pregnant and lactating women and assess for differences in ART retention between Option B+ clients and other ART patients. There were 1989 Option B+ clients who initiated ART in 45 health facilities. The percentage of attrition varied from 9% to 81% across the facilities. The largest health facilities had 38% higher risk of attrition (relative risk [RR]: 1.38, 95% confidence interval [CI]: 1.08-1.77, P = .009). Private institutions had 18% less risk of attrition (RR: 0.82, 95% CI: 0.70-0.96, P = .020). Health facilities located in the West department and the South region had lower risk of attrition. Being on treatment in a large or public health facility or a facility located in the North region was a significant risk factor associated with high attrition among Option B+ clients. The implementation of the Option B+ strategy must be reevaluated in order to effectively eliminate mother-to-child HIV transmission.

  12. Schistosoma mansoni: migration and attrition of irradiated and challenge schistosomula in the mouse

    Energy Technology Data Exchange (ETDEWEB)

    Mastin, A.J.; Wilson, R.A. (York Univ. (UK)); Bickle, Q.D. (Winches Farm Field Station, St. Albans (UK))

    1983-08-01

    The fate of irradiated, immunizing cercariae and challenge schistosomula was investigated in mice using a quantitative, histological technique which would appear to be more efficient in estimating parasite numbers in skin and lungs than does the tissue mincing and incubation recovery technique used previously by other workers. There was evidence for slight retardation of irradiated parasite migration in skin, but death of schistosomula in the skin appeared negligible. The majority of irradiated parasites remained in the lungs until at least day 21 after infection, and that most schistosomula observed at this time were dead. In mice immunized with irradiated cercariae there was no evidence of attrition of the challenge infection in the skin. The migration profile of challenge parasites in the lungs of immunized animals was not significantly different from that of normal parasites in the lungs of naive animals. Dead challenge parasites were observed in the lungs but their numbers were not considered great enough to account for the final attrition measured by perfusion. It is suggested that the remainder of the attrition of challenge schistosomula may occur in the systemic and/or hepatic portal circulation.

  13. Schistosoma mansoni: migration and attrition of irradiated and challenge schistosomula in the mouse

    International Nuclear Information System (INIS)

    Mastin, A.J.; Wilson, R.A.; Bickle, Q.D.

    1983-01-01

    The fate of irradiated, immunizing cercariae and challenge schistosomula was investigated in mice using a quantitative, histological technique which would appear to be more efficient in estimating parasite numbers in skin and lungs than does the tissue mincing and incubation recovery technique used previously by other workers. There was evidence for slight retardation of irradiated parasite migration in skin, but death of schistosomula in the skin appeared negligible. The majority of irradiated parasites remained in the lungs until at least day 21 after infection, and that most schistosomula observed at this time were dead. In mice immunized with irradiated cercariae there was no evidence of attrition of the challenge infection in the skin. The migration profile of challenge parasites in the lungs of immunized animals was not significantly different from that of normal parasites in the lungs of naive animals. Dead challenge parasites were observed in the lungs but their numbers were not considered great enough to account for the final attrition measured by perfusion. It is suggested that the remainder of the attrition of challenge schistosomula may occur in the systemic and/or hepatic portal circulation. (author)

  14. Hospital differences in rates of cesarean deliveries in the Sardinian region: An observational study

    Directory of Open Access Journals (Sweden)

    Massimo Cannas

    2014-11-01

    Full Text Available Background: The rates of cesarean deliveries have been increasing steadily in several European countries in recent decades, with Italy having the second-highest rate (38% in 2010, causing concern and debate about the appropriateness of many interventions. Moreover, some recent studies suggest that rates of common obstetric interventions are not homogeneous across hospitals, maybe not only because of patient case mix but also possibly because of different hospital practices and cultures. Thus, it is important to investigate whether the variation in rates of cesarean sections can be traced back to patient characteristics or whether it depends upon context variables at the hospital level. Objective and method: Using official hospital abstracts on deliveries that occurred in Sardinia over a two-year period, we implement multilevel logistic regression models in order to assess whether the observed differences in cesarean rates across hospitals can be justified by case-mix differences across hospitals. Results: The between-hospital variation in rates of cesarean delivery is estimated to be 0.388 in the model with only the intercept and 0.382 in the model controlling for the mother’s clinical and sociodemographic characteristics. Conclusions: The results show that taking into account the individual characteristics of delivered mothers is not enough to justify the observed variation across hospital rates, suggesting the important role of unobserved variables at the hospital level in determining cesarean section rates.

  15. A new approach to estimate ice dynamic rates using satellite observations in East Antarctica

    Directory of Open Access Journals (Sweden)

    B. Kallenberg

    2017-05-01

    Full Text Available Mass balance changes of the Antarctic ice sheet are of significant interest due to its sensitivity to climatic changes and its contribution to changes in global sea level. While regional climate models successfully estimate mass input due to snowfall, it remains difficult to estimate the amount of mass loss due to ice dynamic processes. It has often been assumed that changes in ice dynamic rates only need to be considered when assessing long-term ice sheet mass balance; however, 2 decades of satellite altimetry observations reveal that the Antarctic ice sheet changes unexpectedly and much more dynamically than previously expected. Despite available estimates on ice dynamic rates obtained from radar altimetry, information about ice sheet changes due to changes in the ice dynamics are still limited, especially in East Antarctica. Without understanding ice dynamic rates, it is not possible to properly assess changes in ice sheet mass balance and surface elevation or to develop ice sheet models. In this study we investigate the possibility of estimating ice sheet changes due to ice dynamic rates by removing modelled rates of surface mass balance, firn compaction, and bedrock uplift from satellite altimetry and gravity observations. With similar rates of ice discharge acquired from two different satellite missions we show that it is possible to obtain an approximation of the rate of change due to ice dynamics by combining altimetry and gravity observations. Thus, surface elevation changes due to surface mass balance, firn compaction, and ice dynamic rates can be modelled and correlated with observed elevation changes from satellite altimetry.

  16. Modeling whole-tree carbon assimilation rate using observed transpiration rates and needle sugar carbon isotope ratios.

    Science.gov (United States)

    Hu, Jia; Moore, David J P; Riveros-Iregui, Diego A; Burns, Sean P; Monson, Russell K

    2010-03-01

    *Understanding controls over plant-atmosphere CO(2) exchange is important for quantifying carbon budgets across a range of spatial and temporal scales. In this study, we used a simple approach to estimate whole-tree CO(2) assimilation rate (A(Tree)) in a subalpine forest ecosystem. *We analysed the carbon isotope ratio (delta(13)C) of extracted needle sugars and combined it with the daytime leaf-to-air vapor pressure deficit to estimate tree water-use efficiency (WUE). The estimated WUE was then combined with observations of tree transpiration rate (E) using sap flow techniques to estimate A(Tree). Estimates of A(Tree) for the three dominant tree species in the forest were combined with species distribution and tree size to estimate and gross primary productivity (GPP) using an ecosystem process model. *A sensitivity analysis showed that estimates of A(Tree) were more sensitive to dynamics in E than delta(13)C. At the ecosystem scale, the abundance of lodgepole pine trees influenced seasonal dynamics in GPP considerably more than Engelmann spruce and subalpine fir because of its greater sensitivity of E to seasonal climate variation. *The results provide the framework for a nondestructive method for estimating whole-tree carbon assimilation rate and ecosystem GPP over daily-to weekly time scales.

  17. Identifying transition rates of ionic channels via observations at a single state

    CERN Document Server

    Deng Ying Chun; Qian Min Ping; Feng Jian Feng

    2003-01-01

    We consider how to determine all transition rates of an ion channel when it can be described by a birth-death chain or a Markov chain on a star-graph with continuous time. It is found that all transition rates are uniquely determined by the distribution of its lifetime and death-time histograms at a single state. An algorithm to calculate the transition rates exactly, based on the statistics of the lifetime and death-time of the Markov chain at the state, is provided. Examples to illustrate how an ion channel activity is fully determined by the observation of a single state of the ion channel are included.

  18. Identifying transition rates of ionic channels via observations at a single state

    International Nuclear Information System (INIS)

    Deng Yingchun; Peng Shenglun; Qian Minping; Feng Jianfeng

    2003-01-01

    We consider how to determine all transition rates of an ion channel when it can be described by a birth-death chain or a Markov chain on a star-graph with continuous time. It is found that all transition rates are uniquely determined by the distribution of its lifetime and death-time histograms at a single state. An algorithm to calculate the transition rates exactly, based on the statistics of the lifetime and death-time of the Markov chain at the state, is provided. Examples to illustrate how an ion channel activity is fully determined by the observation of a single state of the ion channel are included

  19. Identifying transition rates of ionic channels via observations at a single state

    Energy Technology Data Exchange (ETDEWEB)

    Deng Yingchun [School of Mathematics, Peking University, Beijing (China); Peng Shenglun [School of Mathematics, Peking University, Beijing (China); Qian Minping [School of Mathematics, Peking University, Beijing (China); Feng Jianfeng [COGS, Sussex University, Brighton (United Kingdom)

    2003-02-07

    We consider how to determine all transition rates of an ion channel when it can be described by a birth-death chain or a Markov chain on a star-graph with continuous time. It is found that all transition rates are uniquely determined by the distribution of its lifetime and death-time histograms at a single state. An algorithm to calculate the transition rates exactly, based on the statistics of the lifetime and death-time of the Markov chain at the state, is provided. Examples to illustrate how an ion channel activity is fully determined by the observation of a single state of the ion channel are included.

  20. An Evaluation of Lightning Flash Rate Parameterizations Based on Observations of Colorado Storms during DC3

    Science.gov (United States)

    Basarab, B.; Fuchs, B.; Rutledge, S. A.

    2013-12-01

    Predicting lightning activity in thunderstorms is important in order to accurately quantify the production of nitrogen oxides (NOx = NO + NO2) by lightning (LNOx). Lightning is an important global source of NOx, and since NOx is a chemical precursor to ozone, the climatological impacts of LNOx could be significant. Many cloud-resolving models rely on parameterizations to predict lightning and LNOx since the processes leading to charge separation and lightning discharge are not yet fully understood. This study evaluates predicted flash rates based on existing lightning parameterizations against flash rates observed for Colorado storms during the Deep Convective Clouds and Chemistry Experiment (DC3). Evaluating lightning parameterizations against storm observations is a useful way to possibly improve the prediction of flash rates and LNOx in models. Additionally, since convective storms that form in the eastern plains of Colorado can be different thermodynamically and electrically from storms in other regions, it is useful to test existing parameterizations against observations from these storms. We present an analysis of the dynamics, microphysics, and lightning characteristics of two case studies, severe storms that developed on 6 and 7 June 2012. This analysis includes dual-Doppler derived horizontal and vertical velocities, a hydrometeor identification based on polarimetric radar variables using the CSU-CHILL radar, and insight into the charge structure using observations from the northern Colorado Lightning Mapping Array (LMA). Flash rates were inferred from the LMA data using a flash counting algorithm. We have calculated various microphysical and dynamical parameters for these storms that have been used in empirical flash rate parameterizations. In particular, maximum vertical velocity has been used to predict flash rates in some cloud-resolving chemistry simulations. We diagnose flash rates for the 6 and 7 June storms using this parameterization and compare

  1. Explaining transgression in respiratory rate observation methods in the emergency department: A classic grounded theory analysis.

    Science.gov (United States)

    Flenady, Tracy; Dwyer, Trudy; Applegarth, Judith

    2017-09-01

    Abnormal respiratory rates are one of the first indicators of clinical deterioration in emergency department(ED) patients. Despite the importance of respiratory rate observations, this vital sign is often inaccurately recorded on ED observation charts, compromising patient safety. Concurrently, there is a paucity of research reporting why this phenomenon occurs. To develop a substantive theory explaining ED registered nurses' reasoning when they miss or misreport respiratory rate observations. This research project employed a classic grounded theory analysis of qualitative data. Seventy-nine registered nurses currently working in EDs within Australia. Data collected included detailed responses from individual interviews and open-ended responses from an online questionnaire. Classic grounded theory (CGT) research methods were utilised, therefore coding was central to the abstraction of data and its reintegration as theory. Constant comparison synonymous with CGT methods were employed to code data. This approach facilitated the identification of the main concern of the participants and aided in the generation of theory explaining how the participants processed this issue. The main concern identified is that ED registered nurses do not believe that collecting an accurate respiratory rate for ALL patients at EVERY round of observations is a requirement, and yet organizational requirements often dictate that a value for the respiratory rate be included each time vital signs are collected. The theory 'Rationalising Transgression', explains how participants continually resolve this problem. The study found that despite feeling professionally conflicted, nurses often erroneously record respiratory rate observations, and then rationalise this behaviour by employing strategies that adjust the significance of the organisational requirement. These strategies include; Compensating, when nurses believe they are compensating for errant behaviour by enhancing the patient's outcome

  2. Nijmegen Observer-Rated Depression scale for detection of depression in nursing home residents.

    NARCIS (Netherlands)

    Leontjevas, R.; Gerritsen, D.L.; Vernooij-Dassen, M.J.F.J.; Teerenstra, S.; Smalbrugge, M.; Koopmans, R.T.C.M.

    2012-01-01

    OBJECTIVE: This study aims to test the accuracy of the Nijmegen Observer-Rated Depression (NORD) scale, a new short scale for screening of depression in nursing home (NH) residents with and without dementia. METHODS: This cross-sectional study with 103 residents with dementia (N = 19 depressed) and

  3. Nijmegen Observer-Rated Depression scale for detection of depression in nursing home residents

    NARCIS (Netherlands)

    Leontjevas, R.; Gerritsen, D.L.; Vernooij-Dassen, M.J.; Teerenstra, S.; Smalbrugge, M.; Koopmans, R.T.

    2012-01-01

    Objective This study aims to test the accuracy of the Nijmegen Observer-Rated Depression (NORD) scale, a new short scale for screening of depression in nursing home (NH) residents with and without dementia. Methods This cross-sectional study with 103 residents with dementia (N = 19 depressed) and 72

  4. A Behavior Rating Scale for Emotionally Disturbed Students: The Pupil Observation Scale.

    Science.gov (United States)

    Armstrong-Hugg, Robin L.; And Others

    The paper describes development of the Pupil Observation Schedule (POS), a computer based system which provides a framework for assessing, evaluating, and reporting behavioral progress of emotionally disturbed students. The POS is used to rate five skill areas--computation, language, reading, reference, and psychomotor skills; and nine behavioral…

  5. THE HALO MERGER RATE IN THE MILLENNIUM SIMULATION AND IMPLICATIONS FOR OBSERVED GALAXY MERGER FRACTIONS

    International Nuclear Information System (INIS)

    Genel, Shy; Genzel, Reinhard; Bouche, Nicolas; Naab, Thorsten; Sternberg, Amiel

    2009-01-01

    We have developed a new method to extract halo merger rates from the Millennium Simulation. First, by removing superfluous mergers that are artifacts of the standard friends-of-friends (FOF) halo identification algorithm, we find a lower merger rate compared to previous work. The reductions are more significant at lower redshifts and lower halo masses, and especially for minor mergers. Our new approach results in a better agreement with predictions from the extended Press-Schechter model. Second, we find that the FOF halo finder overestimates the halo mass by up to 50% for halos that are about to merge, which leads to an additional ∼20% overestimate of the merger rate. Therefore, we define halo masses by including only particles that are gravitationally bound to their FOF groups. We provide new best-fitting parameters for a global formula to account for these improvements. In addition, we extract the merger rate per progenitor halo, as well as per descendant halo. The merger rate per progenitor halo is the quantity that should be related to observed galaxy merger fractions when they are measured via pair counting. At low-mass/redshift, the merger rate increases moderately with mass and steeply with redshift. At high enough mass/redshift (for the rarest halos with masses a few times the 'knee' of the mass function), these trends break down, and the merger rate per progenitor halo decreases with mass and increases only moderately with redshift. Defining the merger rate per progenitor halo also allows us to quantify the rate at which halos are being accreted onto larger halos, in addition to the minor and major merger rates. We provide an analytic formula that converts any given merger rate per descendant halo into a merger rate per progenitor halo. Finally, we perform a direct comparison between observed merger fractions and the fraction of halos in the Millennium Simulation that have undergone a major merger during the recent dynamical friction time, and find a

  6. Personality, attrition and weight loss in treatment seeking women with obesity.

    Science.gov (United States)

    Dalle Grave, R; Calugi, S; Compare, A; El Ghoch, M; Petroni, M L; Colombari, S; Minniti, A; Marchesini, G

    2015-10-01

    Studies on small samples or in single units applying specific treatment programmes found an association between some personality traits and attrition and weight loss in individuals treated for obesity. We aimed to investigate whether pre-treatment personality traits were associated with weight loss outcomes in the general population of women with obesity. Attrition and weight loss outcomes after 12 months were measured in 634 women with obesity (mean age, 48; body mass index (BMI), 37.8 kg m(-2)) seeking treatment at eight Italian medical centres, applying different medical/cognitive behavioural programmes. Personality traits were assessed with the Temperament and Character Inventory (TCI), eating disorder features with the Binge Eating Scale (BES) and Night Eating Questionnaire (NEQ). Within the 12-month observation period, 32.3% of cases were lost to follow-up. After adjustment for demographic confounders and the severity of eating disorders, no TCI personality traits were significantly associated with attrition, while low scores of the novelty seeking temperament scale remained significantly associated with weight loss ≥ 10% (odds ratio, 0.983; 95% confidence interval, 0.975-0.992). Additional adjustment for education and job did not change the results. We conclude that personality does not systematically influence attrition in women with obesity enrolled into weight loss programmes in the community, whereas an association is maintained between novelty seeking and weight loss outcome. Studies adapting obesity interventions on the basis of individual novelty seeking scores might be warranted to maximize the results on body weight. © 2015 World Obesity.

  7. Increased prevalence of pregnancy and comparative risk of program attrition among individuals starting HIV treatment in East Africa.

    Directory of Open Access Journals (Sweden)

    Charles B Holmes

    Full Text Available The World Health Organization now recommends initiating all pregnant women on life-long antiretroviral therapy (ART, yet there is limited information about the characteristics and program outcomes of pregnant women already on ART in Africa. Our hypothesis was that pregnant women comprised an increasing proportion of those starting ART, and that sub-groups of these women were at higher risk for program attrition.We used the International Epidemiology Databases to Evaluate AIDS- East Africa (IeDEA-EA to conduct a retrospective cohort study including HIV care and treatment programs in Kenya, Uganda, and Tanzania. The cohort consecutively included HIV-infected individuals 13 years or older starting ART 2004-2014. We examined trends over time in the proportion pregnant, their characteristics and program attrition rates compared to others initiating and already receiving ART. 156,474 HIV-infected individuals (67.0% women started ART. The proportion of individuals starting ART who were pregnant women rose from 5.3% in 2004 to 12.2% in 2014. Mean CD4 cell counts at ART initiation, weighted for annual program size, increased from 2004 to 2014, led by non-pregnant women (annual increase 20 cells/mm3 and men (17 cells/mm3 annually, with lower rates of change in pregnant women (10 cells/mm3 per year (p<0.0001. There was no significant difference in the cumulative incidence of program attrition at 6 months among pregnant women starting ART and non-pregnant women. However, healthy pregnant women starting ART (WHO stage 1/2 had a higher rate of attrition rate (9.6%, compared with healthy non-pregnant women (6.5%; in contrast among women with WHO stage 3/4 disease, pregnant women had lower attrition (8.4% than non-pregnant women (14.4%. Among women who initiated ART when healthy and remained in care for six months, subsequent six-month attrition was slightly higher among pregnant women at ART start (3.5% compared to those who were not pregnant (2.4%, (absolute

  8. Increased prevalence of pregnancy and comparative risk of program attrition among individuals starting HIV treatment in East Africa.

    Science.gov (United States)

    Holmes, Charles B; Yiannoutsos, Constantin T; Elul, Batya; Bukusi, Elizabeth; Ssali, John; Kambugu, Andrew; Musick, Beverly S; Cohen, Craig; Williams, Carolyn; Diero, Lameck; Padian, Nancy; Wools-Kaloustian, Kara K

    2018-01-01

    The World Health Organization now recommends initiating all pregnant women on life-long antiretroviral therapy (ART), yet there is limited information about the characteristics and program outcomes of pregnant women already on ART in Africa. Our hypothesis was that pregnant women comprised an increasing proportion of those starting ART, and that sub-groups of these women were at higher risk for program attrition. We used the International Epidemiology Databases to Evaluate AIDS- East Africa (IeDEA-EA) to conduct a retrospective cohort study including HIV care and treatment programs in Kenya, Uganda, and Tanzania. The cohort consecutively included HIV-infected individuals 13 years or older starting ART 2004-2014. We examined trends over time in the proportion pregnant, their characteristics and program attrition rates compared to others initiating and already receiving ART. 156,474 HIV-infected individuals (67.0% women) started ART. The proportion of individuals starting ART who were pregnant women rose from 5.3% in 2004 to 12.2% in 2014. Mean CD4 cell counts at ART initiation, weighted for annual program size, increased from 2004 to 2014, led by non-pregnant women (annual increase 20 cells/mm3) and men (17 cells/mm3 annually), with lower rates of change in pregnant women (10 cells/mm3 per year) (p<0.0001). There was no significant difference in the cumulative incidence of program attrition at 6 months among pregnant women starting ART and non-pregnant women. However, healthy pregnant women starting ART (WHO stage 1/2) had a higher rate of attrition rate (9.6%), compared with healthy non-pregnant women (6.5%); in contrast among women with WHO stage 3/4 disease, pregnant women had lower attrition (8.4%) than non-pregnant women (14.4%). Among women who initiated ART when healthy and remained in care for six months, subsequent six-month attrition was slightly higher among pregnant women at ART start (3.5%) compared to those who were not pregnant (2.4%), (absolute

  9. Computational toxicology: Its essential role in reducing drug attrition.

    Science.gov (United States)

    Naven, R T; Louise-May, S

    2015-12-01

    Predictive toxicology plays a critical role in reducing the failure rate of new drugs in pharmaceutical research and development. Despite recent gains in our understanding of drug-induced toxicity, however, it is urgent that the utility and limitations of our current predictive tools be determined in order to identify gaps in our understanding of mechanistic and chemical toxicology. Using recently published computational regression analyses of in vitro and in vivo toxicology data, it will be demonstrated that significant gaps remain in early safety screening paradigms. More strategic analyses of these data sets will allow for a better understanding of their domain of applicability and help identify those compounds that cause significant in vivo toxicity but which are currently mis-predicted by in silico and in vitro models. These 'outliers' and falsely predicted compounds are metaphorical lighthouses that shine light on existing toxicological knowledge gaps, and it is essential that these compounds are investigated if attrition is to be reduced significantly in the future. As such, the modern computational toxicologist is more productively engaged in understanding these gaps and driving investigative toxicology towards addressing them. © The Author(s) 2015.

  10. Radio observations and the mass flow rate of αCyg (A2Ia)

    International Nuclear Information System (INIS)

    Wolf, B.; Stahl, O.; Altenhoff, W.J.

    1981-01-01

    From the free-free excess at 10μ Barlow and Cohen (1977) derived a mass loss rate of 6.9 x 10 -7 solar masses yr -1 for αCyg. They predicted a 10 GHz radio flux of 2.2 mJy. On the other hand Praderie et al. (1980) derived a considerable lower mass loss rate of 1.1 x 10 -8 -8 solar masses yr -1 from a curve of growth analysis of the envelope ultraviolet FeII-lines of αCyg. Radio observations are desirable to make a decision about these discrepant results. Therefore the authors observed αCyg at 15 GHz with the 100 m telescope of the MPIfR at Effelsberg. The observations are discussed together with recent VLA data of Abbott et al. (1980). (Auth.)

  11. The management of over closured anterior teeth due to attrition

    Directory of Open Access Journals (Sweden)

    Eha Djulaeha

    2009-12-01

    Full Text Available Background: Tooth is the hardest tissue in human body, that can be injured because of attrition process. For old people, denture attrition process is caused by psysiological process relating with the mastication function which also supported by some bad habits such an bruxism, premature contact, and consuming habit of abrasive food. Attrition or abrasion can also be happened with patien’t dentition who does not have teeth subtutition for long time due the lost of their maxillary as well as mandibulary. The pasient will loose their vertical dimension of occlusion, injure, and the lower jaw becomes over closed which is called over closure. Purpose: This article reported the management of over closured anterior teeth due to attrition. Case: a seventy six year old woman patient came to Prosthodontic Clinic in Faculty of Dentistry, Airlangga University, to rehabilitate her upper and lower severe attrited anterior teeth and her posterior teeth. The patient has experienced of wearing acrylic removable mandibular partial denture ten years ago. Unfortunaly, the denture was uncomfortable, and she did not wear it anymore since five years ago. Case management: The severe attrition of anterior teeth with the lost of occlusal vertical dimension can be treated by improving the occlusal vertical dimension gradually. The treatment is then followed by the increasing of the height of the anterior teeth by lengthening the crown teeth of upper jaw with 12 units of span bridge and the acrylic removable partial denture of lower jaw. Conclusion: The severe attrition of anterior teeth with the lost of occlusal vertical dimension can be treated by improving the occlusal vertical dimension gradually, using long span bridge and acrylic removable partial denture.

  12. Chaotic spin exchange: is the spin non-flip rate observable?

    International Nuclear Information System (INIS)

    Senba, Masayoshi

    1994-01-01

    If spin exchange is of the Poisson nature, that is, if the time distribution of collisions obeys an exponential distribution function and the collision process is random, the muon spin depolarization is determined only by the spin flip rate regardless of the spin non-flip rate. In this work, spin exchange is discussed in the case of chaotic spin exchange, where the distribution of collision time sequences, generated by a deterministic equation, is exponential but not random (deterministic chaos). Even though this process has the same time distribution as a Poisson process, the muon polarization is affected by the spin non-flip rate. Having an exponential time distribution function is not a sufficient condition for the non-observation of the spin non-flip rate and it is essential that the process is also random. (orig.)

  13. Does multimorbidity influence the occurrence rates of chronic conditions? A claims data based comparison of expected and observed prevalence rates.

    Directory of Open Access Journals (Sweden)

    Ingmar Schäfer

    Full Text Available OBJECTIVE: Multimorbidity is a complex phenomenon with an almost endless number of possible disease combinations with unclear implications. One important aspect in analyzing the clustering of diseases is to distinguish between random coexistence and statistical dependency. We developed a model to account for random coexistence based on stochastic distribution. We analyzed if the number of diseases of the patients influences the occurrence rates of chronic conditions. METHODS: We analyzed claims data of 121,389 persons aged 65+ using a list of 46 chronic conditions. Expected prevalences were simulated by drawing without replacement from all observed diseases using observed overall prevalences as initial probability weights. To determine if a disease occurs more or less frequently than expected by chance we calculated observed-minus-expected deltas for each disease. We defined clinical relevance as |delta| ≥ 5.0%. 18 conditions were excluded because of a prevalence < 5.0%. RESULTS: We found that (1 two chronic conditions (e.g. hypertension were more frequent than expected in patients with a low number of comorbidities; (2 four conditions (e.g. renal insufficiency were more frequent in patients with many comorbidities; (3 six conditions (e.g. cancer were less frequent with many comorbidities; and (4 16 conditions had an average course of prevalences. CONCLUSION: A growing extent of multimorbidity goes along with a rapid growth of prevalences. This is for the largest part merely a stochastic effect. If we account for this effect we find that only few diseases deviate from the expected prevalence curves. Causes for these deviations are discussed. Our approach also has methodological implications: Naive analyses of multimorbidity might easily be affected by bias, because the prevalence of all chronic conditions necessarily increases with a growing extent of multimorbidity. We should therefore always examine and discuss the stochastic interrelations

  14. Attrition and bias in the MRC cognitive function and ageing study: an epidemiological investigation

    Directory of Open Access Journals (Sweden)

    Matthews Fiona E

    2004-04-01

    Full Text Available Abstract Background Any hypothesis in longitudinal studies may be affected by attrition and poor response rates. The MRC Cognitive Function and Ageing study (MRC CFAS is a population based longitudinal study in five centres with identical methodology in England and Wales each recruiting approximately 2,500 individuals. This paper aims to identify potential biases in the two-year follow-up interviews. Methods Initial non-response: Those not in the baseline interviews were compared in terms of mortality to those who were in the baseline interviews at the time of the second wave interviews (1993–1996. Longitudinal attrition: Logistic regression analysis was used to examine baseline differences between individuals who took part in the two-year longitudinal wave compared with those who did not. Results Initial non-response: Individuals who moved away after sampling but before baseline interview were 1.8 times more likely to die by two years (95% Confidence interval(CI 1.3–2.4 compared to respondents, after adjusting for age. The refusers had a slightly higher, but similar mortality pattern to responders (Odds ratio 1.2, 95%CI 1.1–1.4. Longitudinal attrition: Predictors for drop out due to death were being older, male, having impaired activities of daily living, poor self-perceived health, poor cognitive ability and smoking. Similarly individuals who refused were more likely to have poor cognitive ability, but had less years of full-time education and were more often living in their own home though less likely to be living alone. There was a higher refusal rate in the rural centres. Individuals who moved away or were uncontactable were more likely to be single, smokers, demented or depressed and were less likely to have moved if in warden-controlled accommodation at baseline. Conclusions Longitudinal estimation of factors mentioned above could be biased, particularly cognitive ability and estimates of movements from own home to residential homes

  15. Observations of turbulent energy dissipation rate in the upper ocean of the central South China Sea

    Science.gov (United States)

    Chen, G.

    2016-02-01

    Measurements of turbulent energy dissipation rate, velocity, temperature, and salinity were obtained in the upper ocean of the central South China Sea (14.5˚N, 117.0˚E) during an experimental campaign from May 11th to 13th 2010. Dissipation rate was elevated ( 10-7 Wkg-1) at night by convection mixing and was weakened ( 10-9 Wkg-1) in daytime due to the warming stratification. Thermocline dissipation rate varied with time ( 10-9 Wkg-1 to 10-8 Wkg-1) under the influence of internal waves. Energy was transferred from the diurnal internal tides to high frequency internal waves through nonlinear wave-wave interactions. This energy cascade process was accompanied by elevated shear and enhanced dissipation, which played an important role in the turbulent mixing in thermocline. Compare with the thermocline dissipation, dissipation below the thermocline was more stable and weak ( 10-10 Wkg-1). The observed dissipation rate during the measurement was well parameterized by the MacKinnon-Gregg parameterization (a model based on a reinterpretation of wave-wave interaction theory), whereas the Gregg-Henyey parameterization was not in good agreement with the observed dissipation rate.

  16. Attrition, occlusion, (dys)function, and intervention: a systematic review.

    Science.gov (United States)

    van 't Spijker, Arie; Kreulen, Cees M; Creugers, Nico H J

    2007-06-01

    Attrition and occlusal factors and masticatory function or dysfunction are thought to be related. This study aims to systematically review the literature on this topic with the emphasis to find evidence for occlusion-based treatment protocols for attrition. Literature was searched using PubMed (1980 to 2/2006) and the Cochrane Library of Clinical Trials with the keywords 'tooth' and 'wear'. Five steps were followed. Exclusion was based on the following: (1) reviews, case-reports, studies on non-human tooth material, and studies not published in English and (2) historical or forensic studies. Included were (3) in vivo studies. Next, studies on (4) occlusal factors, function or dysfunction [temporomandibular disorders (TMD), bruxism], or intervention, and (5) attrition were included. Two investigators independently assessed the abstracts; measure of agreement was calculated using Cohen's kappa; disagreement was resolved by discussion. Full-text articles were obtained and correlation between outcomes on occlusal factors, (dys)function, treatment, and attrition were retrieved. References in the papers included in the final analysis were cross-matched with the original list of references to add references that met the inclusion criteria. The search procedure revealed 1289 references on tooth wear. The numbers of included studies after each step were (1) 345 (kappa=0.8), (2) 287 (kappa=0.87), (3) 174 (kappa=0.99), (4) 81 (kappa=0.71), and (5) 27 (kappa=0.68). Hand searches through the reference lists revealed six additional papers to be included. Analysis of the 33 included papers failed to find sound evidence for recommending a certain occlusion-based treatment protocol above another in the management of attrition. Some studies reported correlations between attrition and anterior spatial relationships. No studies were found suggesting that absent posterior support necessarily leads to increased attrition, though one study found that fewer number of teeth resulted in

  17. A Model for Estimation of Rain Rate on Tropical Land from TRMM Microwave Imager Radiometer Observations

    OpenAIRE

    C., PRABHAKARA; R., IACOVAZZI; J. M., YOO; K. M., KIM; NASA Goddard Space Flight Center; Center for Research on the Changing Earth System; EWHA Womans University; Science Systems and Applications, Inc.

    2005-01-01

    Over the tropical land regions scatter plots of the rain rate (R_), deduced from the TRMM Precipitation Radar (PR) versus the observed 85GHz brightness temperature (T_) made by the TRMM Microwave Imager (TMI) radiometer, for a period of a season over a given geographic region of 3°×5°(lat×lon), indicate that there are two maxima in rain rate. One strong maximum occurs when T_ has a value of about 220K, and the other weaker one when T_ is much colder ~150K. Also these two maxima are vividly re...

  18. Australian aboriginal tooth succession, interproximal attrition, and Begg's theory.

    Science.gov (United States)

    Corruccini, R S

    1990-04-01

    In 1954, P.R. Begg analyzed interproximal attrition as a prehistorically universal mechanism to reduce tooth size. With modern processed diets and the virtual disappearance of constant interproximal attrition, Begg asserted, teeth remain too large for the arches and become crowded. Later investigators have questioned Begg's estimate of attritional tooth-size reduction, as well as aspects of his theory relating the succession sequence of permanent teeth to different malocclusions. The present paper examines the theory using longitudinal casts and records of modern Australian aborigines who are among the first generation lacking notable interproximal attrition thanks to a "modernized" diet. Deciduous and permanent tooth size, arch size, and occlusal relational variables were analyzed with respect to the expected occlusal outcomes in the absence of attritional tooth reduction. Permanent incisor overjet correlated with crowding status, as predicted by Begg. On the other hand, longer teeth did not relate to crowding in general nor to crowding in relevant local areas or during developmental stages. Unfavorable leeway space did not relate clearly to crowding or other malocclusions. Lowered correlations among structures and narrowness of the maxilla related more significantly to malocclusion. These results are in keeping with recent thinking that small jaws rather than large teeth underlie tooth/arch discrepancy.

  19. Attrition during graduate medical education: medical school perspective.

    Science.gov (United States)

    Andriole, Dorothy A; Jeffe, Donna B; Hageman, Heather L; Klingensmith, Mary E; McAlister, Rebecca P; Whelan, Alison J

    2008-12-01

    To identify predictors of attrition during graduate medical education (GME) in a single medical school cohort of contemporary US medical school graduates. Retrospective cohort study. Single medical institution. Recent US allopathic medical school graduates. Attrition from initial GME program. Forty-seven of 795 graduates (6%) did not complete the GME in their initial specialty of choice. At bivariate analysis, attrition was associated with election to the Alpha Omega Alpha Honor Medical Society, being an MD-PhD degree holder, and specialty choice (all P PhD degree holder (odds ratio, 3.43; 95% confidence interval, 1.27-9.26; P = .02), election to Alpha Omega Alpha (2.19; 1.04-4.66; P = .04), choice of general surgery for GME (5.32; 1.98-14.27; P < .001), and choice of 5-year surgical specialty including those surgical specialties with a GME training requirement of 5 years or longer (2.74; 1.16-6.44; P = .02) each independently predicted greater likelihood of attrition. Academically highly qualified graduates and graduates who chose training in general surgery or in a 5-year surgical specialty were at increased risk of attrition during GME.

  20. Observation of Repetition-Rate Dependent Emission From an Un-Gated Thermionic Cathode Rf Gun

    Energy Technology Data Exchange (ETDEWEB)

    Edelen, J. P.; Sun, Y.; Harris, J.R.; Lewellen, J.W.

    2017-06-02

    Recent work at Fermilab in collaboration with the Advanced Photon Source and members of other national labs, designed an experiment to study the relationship between the RF repetition rate and the average current per RF pulse. While existing models anticipate a direct relationship between these two parameters we observed an inverse relationship. We believe this is a result of damage to the barium coating on the cathode surface caused by a change in back-bombardment power that is unaccounted for in the existing theories. These observations shed new light on the challenges and fundamental limitations associated with scaling an ungated thermionic cathode RF gun to high average current.

  1. Parameterizing the Magnetopause Reconnection Rate from Observations of the Expanding Polar Cap

    Science.gov (United States)

    Milan, S. E.; Gosling, J. S.; Hubert, B.

    2012-04-01

    We determine an expression for the magnetopause reconnection rate in terms of upstream interplanetary parameters. We quantify the dayside reconnection rate from observations of the expanding polar cap when the nightside reconnection rate is assumed to be zero. The polar cap open flux is calculated from auroral images collected by the Imager for Magnetopause-to-Aurora Global Exploration (IMAGE) Far Ultraviolet camera (FUV), and its rate of increase is correlated with upstream solar wind and interplanetary magnetic field measurements from the OMNI data-set. We find that the reconnection rate is successfully reproduced by considering the magnetic flux transport within a 4 Re-wide channel within the solar wind (with an additional small correction for the solar wind velocity) and an IMF clock angle dependence with an exponent of 9/2. Contrary to several previous studies we do not find a dependence of the reconnection rate on solar wind density. We discuss our findings in the context of previous studies and solar wind-magnetosphere coupling models.

  2. Rate estimation in partially observed Markov jump processes with measurement errors

    OpenAIRE

    Amrein, Michael; Kuensch, Hans R.

    2010-01-01

    We present a simulation methodology for Bayesian estimation of rate parameters in Markov jump processes arising for example in stochastic kinetic models. To handle the problem of missing components and measurement errors in observed data, we embed the Markov jump process into the framework of a general state space model. We do not use diffusion approximations. Markov chain Monte Carlo and particle filter type algorithms are introduced, which allow sampling from the posterior distribution of t...

  3. Retention and risk factors for attrition in a large public health ART program in Myanmar: a retrospective cohort analysis.

    Directory of Open Access Journals (Sweden)

    Aye Thida

    Full Text Available BACKGROUND: The outcomes from an antiretroviral treatment (ART program within the public sector in Myanmar have not been reported. This study documents retention and the risk factors for attrition in a large ART public health program in Myanmar. METHODS: A retrospective analysis of a cohort of adult patients enrolled in the Integrated HIV Care (IHC Program between June 2005 and October 2011 and followed up until April 2012 is presented. The primary outcome was attrition (death or loss-follow up; a total of 10,223 patients were included in the 5-year cumulative survival analysis. Overall 5,718 patients were analyzed for the risk factors for attrition using both logistic regression and flexible parametric survival models. RESULT: The mean age was 36 years, 61% of patients were male, and the median follow up was 13.7 months. Overall 8,564 (84% patients were retained in ART program: 750 (7% were lost to follow-up and 909 (9% died. During the 3 years follow-up, 1,542 attritions occurred over 17,524 person years at risk, giving an incidence density of 8.8% per year. The retention rates of participants at 12, 24, 36, 48 and 60 months were 86, 82, 80, 77 and 74% respectively. In multivariate analysis, being male, having high WHO staging, a low CD4 count, being anaemic or having low BMI at baseline were independent risk factors for attrition; tuberculosis (TB treatment at ART initiation, a prior ART course before program enrollment and literacy were predictors for retention in the program. CONCLUSION: High retention rate of IHC program was documented within the public sector in Myanmar. Early diagnosis of HIV, nutritional support, proper investigation and treatment for patients with low CD4 counts and for those presenting with anaemia are crucial issues towards improvement of HIV program outcomes in resource-limited settings.

  4. Retention and risk factors for attrition in a large public health ART program in Myanmar: a retrospective cohort analysis.

    Science.gov (United States)

    Thida, Aye; Tun, Sai Thein Than; Zaw, Sai Ko Ko; Lover, Andrew A; Cavailler, Philippe; Chunn, Jennifer; Aye, Mar Mar; Par, Par; Naing, Kyaw Win; Zan, Kaung Nyunt; Shwe, Myint; Kyaw, Thar Tun; Waing, Zaw Htoon; Clevenbergh, Philippe

    2014-01-01

    The outcomes from an antiretroviral treatment (ART) program within the public sector in Myanmar have not been reported. This study documents retention and the risk factors for attrition in a large ART public health program in Myanmar. A retrospective analysis of a cohort of adult patients enrolled in the Integrated HIV Care (IHC) Program between June 2005 and October 2011 and followed up until April 2012 is presented. The primary outcome was attrition (death or loss-follow up); a total of 10,223 patients were included in the 5-year cumulative survival analysis. Overall 5,718 patients were analyzed for the risk factors for attrition using both logistic regression and flexible parametric survival models. The mean age was 36 years, 61% of patients were male, and the median follow up was 13.7 months. Overall 8,564 (84%) patients were retained in ART program: 750 (7%) were lost to follow-up and 909 (9%) died. During the 3 years follow-up, 1,542 attritions occurred over 17,524 person years at risk, giving an incidence density of 8.8% per year. The retention rates of participants at 12, 24, 36, 48 and 60 months were 86, 82, 80, 77 and 74% respectively. In multivariate analysis, being male, having high WHO staging, a low CD4 count, being anaemic or having low BMI at baseline were independent risk factors for attrition; tuberculosis (TB) treatment at ART initiation, a prior ART course before program enrollment and literacy were predictors for retention in the program. High retention rate of IHC program was documented within the public sector in Myanmar. Early diagnosis of HIV, nutritional support, proper investigation and treatment for patients with low CD4 counts and for those presenting with anaemia are crucial issues towards improvement of HIV program outcomes in resource-limited settings.

  5. One (rating) from many (observations): Factors affecting the individual assessment of voice behavior in groups.

    Science.gov (United States)

    Podsakoff, Nathan P; Maynes, Timothy D; Whiting, Steven W; Podsakoff, Philip M

    2015-07-01

    This article reports an investigation into how individuals form perceptions of overall voice behavior in group contexts. More specifically, the authors examine the effect of the proportion of group members exhibiting voice behavior in the group, the frequency of voice events in the group, and the measurement item referent (group vs. individual) on an individual's ratings of group voice behavior. In addition, the authors examine the effect that measurement item referent has on the magnitude of the relationship observed between an individual's ratings of group voice behavior and perceptions of group performance. Consistent with hypotheses, the results from 1 field study (N = 220) and 1 laboratory experiment (N = 366) indicate that: (a) When group referents were used, raters relied on the frequency of voice events (and not the proportion of group members exhibiting voice) to inform their ratings of voice behavior, whereas the opposite was true when individual-referent items were used, and (b) the magnitude of the relationship between observers' ratings of group voice behavior and their perceptions of group performance was higher when raters used group-referent, as opposed to an individual-referent, items. The authors discuss the implications of their findings for scholars interested in studying behavioral phenomena occurring in teams, groups, and work units in organizational behavior research. (c) 2015 APA, all rights reserved).

  6. A crowdsourced nickel-and-dime approach to analog OBM research: A behavioral economic framework for understanding workforce attrition.

    Science.gov (United States)

    Henley, Amy J; DiGennaro Reed, Florence D; Reed, Derek D; Kaplan, Brent A

    2016-09-01

    Incentives are a popular method to achieve desired employee performance; however, research on optimal incentive magnitude is lacking. Behavioral economic demand curves model persistence of responding in the face of increasing cost and may be suitable to examine the reinforcing value of incentives on work performance. The present use-inspired basic study integrated an experiential human operant task within a crowdsourcing platform to evaluate the applicability of behavioral economics for quantifying changes in workforce attrition. Participants included 88 Amazon Mechanical Turk Workers who earned either a $0.05 or $0.10 incentive for completing a progressively increasing response requirement. Analyses revealed statistically significant differences in breakpoint between the two groups. Additionally, a novel translation of the Kaplan-Meier survival-curve analyses for use within a demand curve framework allowed for examination of elasticity of workforce attrition. Results indicate greater inelastic attrition in the $0.05 group. We discuss the benefits of a behavioral economic approach to modeling employee behavior, how the metrics obtained from the elasticity of workforce attrition analyses (e.g., P max ) may be used to set goals for employee behavior while balancing organizational costs, and how economy type may have influenced observed outcomes. © 2016 Society for the Experimental Analysis of Behavior.

  7. On the observability of turbulent transport rates by Argo: supporting evidence from an inversion experiment

    Directory of Open Access Journals (Sweden)

    G. Forget

    2015-10-01

    Full Text Available Although estimation of turbulent transport parameters using inverse methods is not new, there is little evaluation of the method in the literature. Here, it is shown that extended observation of the broad-scale hydrography by Argo provides a path to improved estimates of regional turbulent transport rates. Results from a 20-year ocean state estimate produced with the ECCO v4 (Estimating the Circulation and Climate of the Ocean, version 4 non-linear inverse modeling framework provide supporting evidence. Turbulent transport parameter maps are estimated under the constraints of fitting the extensive collection of Argo profiles collected through 2011. The adjusted parameters dramatically reduce misfits to in situ profiles as compared with earlier ECCO solutions. They also yield a clear reduction in the model drift away from observations over multi-century-long simulations, both for assimilated variables (temperature and salinity and independent variables (biogeochemical tracers. Despite the minimal constraints imposed specifically on the estimated parameters, their geography is physically plausible and exhibits close connections with the upper-ocean stratification as observed by Argo. The estimated parameter adjustments furthermore have first-order impacts on upper-ocean stratification and mixed layer depths over 20 years. These results identify the constraint of fitting Argo profiles as an effective observational basis for regional turbulent transport rate inversions. Uncertainties and further improvements of the method are discussed.

  8. Study of Attrition Documentation at the U.S. Navy Recruit Training Command

    National Research Council Canada - National Science Library

    Condon, Nancy K; Eckenrode, John E

    2006-01-01

    .... Navy's Recruit Training Command (RTC). A random sample of 754 "retained files" from Customer Service Desk RTC was examined for attrition documentation and the information obtained was compared with attrition documentation contained...

  9. A Longitudinal Examination of First Term Attrition and Reenlistment among FY1999 Enlisted Accessions

    National Research Council Canada - National Science Library

    Strickland, William J

    2005-01-01

    ... the service, completed training segments, conducted duty assignments, and left the service. These models explored reasons for attrition and reenlistment intentions, and suggested management strategies that might be employed to reduce attrition...

  10. Blood Telomere Length Attrition and Cancer Development in the Normative Aging Study Cohort

    Directory of Open Access Journals (Sweden)

    Lifang Hou

    2015-06-01

    Interpretation: Age-related BTL attrition was faster in cancer cases but their age-adjusted BTL attrition began decelerating as diagnosis approached. This may explain prior inconsistencies and help develop BTL as a cancer detection biomarker.

  11. Rates for parallax-shifted microlensing events from ground-based observations of the galactic bulge

    International Nuclear Information System (INIS)

    Buchalter, A.; Kamionkowski, M.

    1997-01-01

    The parallax effect in ground-based microlensing (ML) observations consists of a distortion to the standard ML light curve arising from the Earth's orbital motion. This can be used to partially remove the degeneracy among the system parameters in the event timescale, t 0 . In most cases, the resolution in current ML surveys is not accurate enough to observe this effect, but parallax could conceivably be detected with frequent follow-up observations of ML events in progress, providing the photometric errors are small enough. We calculate the expected fraction of ML events where the shape distortions will be observable by such follow-up observations, adopting Galactic models for the lens and source distributions that are consistent with observed microlensing timescale distributions. We study the dependence of the rates for parallax-shifted events on the frequency of follow-up observations and on the precision of the photometry. For example, we find that for hourly observations with typical photometric errors of 0.01 mag, 6% of events where the lens is in the bulge, and 31% of events where the lens is in the disk (or ∼10% of events overall), will give rise to a measurable parallax shift at the 95% confidence level. These fractions may be increased by improved photometric accuracy and increased sampling frequency. While long-duration events are favored, the surveys would be effective in picking out such distortions in events with timescales as low as t 0 ∼20 days. We study the dependence of these fractions on the assumed disk mass function and find that a higher parallax incidence is favored by mass functions with higher mean masses. Parallax measurements yield the reduced transverse speed, v, which gives both the relative transverse speed and lens mass as a function of distance. We give examples of the accuracies with which v may be measured in typical parallax events. (Abstract Truncated)

  12. Relationships between Medicare Advantage contract characteristics and quality-of-care ratings: an observational analysis of Medicare Advantage star ratings.

    Science.gov (United States)

    Xu, Peng; Burgess, James F; Cabral, Howard; Soria-Saucedo, Rene; Kazis, Lewis E

    2015-03-03

    The Centers for Medicare & Medicaid Services (CMS) publishes star ratings on Medicare Advantage (MA) contracts to measure plan quality of care with implications for reimbursement and bonuses. To investigate whether MA contract characteristics are associated with quality of care through the Medicare plan star ratings. Retrospective study of MA star ratings in 2010. Unadjusted and adjusted multivariable linear regression models assessed the relationship between 5-star rating summary scores and plan characteristics. CMS MA contracts nationally. 409 (71%) of a total of 575 MA contracts, covering 10.56 million Medicare beneficiaries (90% of the MA population) in the United States in 2010. The MA quality ratings summary score (stars range from 1 to 5) is a quality measure based on 36 indicators related to processes of care, health outcomes, access to care, and beneficiary satisfaction. Nonprofit, larger, and older MA contracts were more likely to receive higher star ratings. Star ratings ranged from 2 to 5. Nonprofit contracts received an average 0.55 (95% CI, 0.42 to 0.67) higher star ratings than for-profit contracts (P  star ratings than for-profit contracts. When comparing health plans in the future, the CMS should give increasing attention to for-profit plans with lower quality ratings and consider developing programs to assist newer and smaller plans in improving their care for Medicare beneficiaries. None.

  13. The Anaclitic-Introjective Depression Assessment: Development and preliminary validity of an observer-rated measure.

    Science.gov (United States)

    Rost, Felicitas; Luyten, Patrick; Fonagy, Peter

    2018-03-01

    The two-configurations model developed by Blatt and colleagues offers a comprehensive conceptual and empirical framework for understanding depression. This model suggests that depressed patients struggle, at different developmental levels, with issues related to dependency (anaclitic issues) or self-definition (introjective issues), or a combination of both. This paper reports three studies on the development and preliminary validation of the Anaclitic-Introjective Depression Assessment, an observer-rated assessment tool of impairments in relatedness and self-definition in clinical depression based on the item pool of the Shedler-Westen Assessment Procedure. Study 1 describes the development of the measure using expert consensus rating and Q-methodology. Studies 2 and 3 report the assessment of its psychometric properties, preliminary reliability, and validity in a sample of 128 patients diagnosed with treatment-resistant depression. Four naturally occurring clusters of depressed patients were identified using Q-factor analysis, which, overall, showed meaningful and theoretically expected relationships with anaclitic/introjective prototypes as formulated by experts, as well as with clinical, social, occupational, global, and relational functioning. Taken together, findings reported in this paper provide preliminary evidence for the reliability and validity of the Anaclitic-Introjective Depression Assessment, an observer-rated measure that allows the detection of important nuanced differentiations between and within anaclitic and introjective depression. Copyright © 2017 John Wiley & Sons, Ltd.

  14. Global observation of Omori-law decay in the rate of triggered earthquakes

    Science.gov (United States)

    Parsons, T.

    2001-12-01

    Triggered earthquakes can be large, damaging, and lethal as evidenced by the 1999 shocks in Turkey and the 2001 events in El Salvador. In this study, earthquakes with M greater than 7.0 from the Harvard CMT catalog are modeled as dislocations to calculate shear stress changes on subsequent earthquake rupture planes near enough to be affected. About 61% of earthquakes that occurred near the main shocks are associated with calculated shear stress increases, while ~39% are associated with shear stress decreases. If earthquakes associated with calculated shear stress increases are interpreted as triggered, then such events make up at least 8% of the CMT catalog. Globally, triggered earthquakes obey an Omori-law rate decay that lasts between ~7-11 years after the main shock. Earthquakes associated with calculated shear stress increases occur at higher rates than background up to 240 km away from the main-shock centroid. Earthquakes triggered by smaller quakes (foreshocks) also obey Omori's law, which is one of the few time-predictable patterns evident in the global occurrence of earthquakes. These observations indicate that earthquake probability calculations which include interactions from previous shocks should incorporate a transient Omori-law decay with time. In addition, a very simple model using the observed global rate change with time and spatial distribution of triggered earthquakes can be applied to immediately assess the likelihood of triggered earthquakes following large events, and can be in place until more sophisticated analyses are conducted.

  15. Differences in rain rate intensities between TRMM observations and community atmosphere model simulations

    Science.gov (United States)

    Deng, Yi; Bowman, Kenneth P.; Jackson, Charles

    2007-01-01

    Precipitation related latent heating is important in driving the atmospheric general circulation and in generating intraseasonal to decadal atmospheric variability. Our ability to project future climate change, especially trends in costly precipitation extremes, hinges upon whether coupled GCMs capture processes that affect precipitation characteristics. Our study compares the tropical-subtropical precipitation characteristics of simulations by the NCAR CAM3.1 atmospheric GCM and observations derived from the NASA Tropical Rainfall Measuring Mission (TRMM) satellite. Despite a fairly good simulation of the annual mean rain rate, CAM rains about 10-50% more often than the real world and fails to capture heavy rainfall associated with deep convective systems over subtropical South America and U.S. Southern Plains. When it rains, there is a likelihood of 0.96-1.0 that it rains lightly in the model, compared to values of 0.84-1.0 in TRMM data. On the other hand, the likelihood of the occurrence of moderate to heavy rainfall is an order of magnitude higher in observations (0.12-0.2) than that in the model (model compensates for the lack of heavy precipitation through raining more frequently within the light rain category, which leads to an annual rainfall amount close to what is observed. CAM captures the qualitative change of rain rate PDF from a "dry" oceanic to a "wet" oceanic region, but it fails to simulate the change of precipitation characteristics from an oceanic region to a land region where thunderstorm rainfall dominates.

  16. Rates of ingestion and their variability between individual calanoid copepods: Direct observations

    Energy Technology Data Exchange (ETDEWEB)

    Paffenhoefer, G.A.; Lewis, K.D. [Skidaway Inst. of Oceanography, Savannah, GA (United States); Bundy, M.H. [Skidaway Inst. of Oceanography, Savannah, GA (United States)]|[Alfred-Wegener-Institut fuer Polar- und Meeresforschung, Bremerhaven (Germany). Inst. fuer Fernerkundung (IFE); Metz, C. [Alfred-Wegener-Institut fuer Polar- und Meeresforschung, Bremerhaven (Germany). Inst. fuer Fernerkundung (IFE)

    1995-12-01

    The goals of this study were to determine rates of ingestion and fecal pellet release, and their variability, for individual planktonic copepods over extended periods of time (>20 min). Ingestions and rejections of individual cells of the diatom Thalassiosira eccentrica by a adult females of the calanoid Paracalanus aculeatus were directly quantified by observing individual copepods continuously at cell concentrations ranging from 0.1 to 1.2 mm{sup 3} l{sup {minus}1}. Average ingestion rates increased with increasing food concentration, but were not significantly different between 0.3 and 1.0 mm{sup 3} l{sup {minus}1} (9.8 and 32.7 {mu}g Cl{sup {minus}1}) of T.eccentrica. Rates of cell rejections were low and similar at 0.1 and 0.3. but were significantly higher at 1.0 mm{sup 3} l{sup {minus}1}. The coefficients of variation for average ingestion rates of individual copepods hardly differed between food concentrations, ranging from 17 to 22%, and were close to those for average fecal pellet release intervals which ranged from 15 to 21%. A comparison between individuals at each food concentration found no significant differences at 1.0; at 0.1 and 0.3 mm{sup 3} l{sup {minus}1}, respectively, ingestion rates of four out of five females did not differ significantly from each other. Average intervals between fecal pellet releases were similar at 0.3 and 1.0 mm{sup 3} l{sup {minus}1}. Fecal pellet release intervals between individuals were significantly different at each food concentration; these significant differences were attributed to rather narrow ranges of pellet release intervals of each individual female. Potential sources/causes of variability in the sizes and rates of copepods in the ocean are evaluated.

  17. Binary and multi-category ratings in a laboratory observer performance study: a comparison.

    Science.gov (United States)

    Gur, David; Bandos, Andriy I; King, Jill L; Klym, Amy H; Cohen, Cathy S; Hakim, Christiane M; Hardesty, Lara A; Ganott, Marie A; Perrin, Ronald L; Poller, William R; Shah, Ratan; Sumkin, Jules H; Wallace, Luisa P; Rockette, Howard E

    2008-10-01

    -reader average (0.016) was (-0.0206, 0.0631) (two-sided p-value 0.35). In conclusion the authors found that in retrospective observer performance studies the use of a binary response or a semi-continuous rating scale led to consistent results in terms of performance as measured by sensitivity-specificity operating points.

  18. Determination of hyperfine-induced transition rates from observations of a planetary nebula.

    Science.gov (United States)

    Brage, Tomas; Judge, Philip G; Proffitt, Charles R

    2002-12-31

    Observations of the planetary nebula NGC3918 made with the STIS instrument on the Hubble Space Telescope reveal the first unambiguous detection of a hyperfine-induced transition 2s2p 3P(o)(0)-->2s2 1S0 in the berylliumlike emission line spectrum of N IV at 1487.89 A. A nebular model allows us to confirm a transition rate of 4x10(-4) sec(-1)+/-33% for this line. The measurement represents the first independent confirmation of the transition rate of hyperfine-induced lines in low ionization stages, and it provides support for the techniques used to compute these transitions for the determination of very low densities and isotope ratios.

  19. Supplement: The Rate of Binary Black Hole Mergers Inferred from Advanced LIGO Observations Surrounding GW150914

    Science.gov (United States)

    Abbott, B. P.; Abbott, R.; Abbott, T. D.; Abernathy, M. R.; Acernese, F.; Ackley, K.; Adams, C.; Adams, T.; Addesso, P.; Adhikari, R. X.; hide

    2016-01-01

    This article provides supplemental information for a Letter reporting the rate of (BBH) coalescences inferred from 16 days of coincident Advanced LIGO observations surrounding the transient (GW) signal GW150914. In that work wereported various rate estimates whose 90% confidence intervals fell in the range 2600 Gpc(exp -3) yr(exp -1). Here we givedetails on our method and computations, including information about our search pipelines, a derivation of ourlikelihood function for the analysis, a description of the astrophysical search trigger distribution expected frommerging BBHs, details on our computational methods, a description of the effects and our model for calibrationuncertainty, and an analytic method for estimating our detector sensitivity, which is calibrated to our measurements.

  20. Team-Based Learning Reduces Attrition in a First-Semester General Chemistry Course

    Science.gov (United States)

    Comeford, Lorrie

    2016-01-01

    Team-based learning (TBL) is an instructional method that has been shown to reduce attrition and increase student learning in a number of disciplines. TBL was implemented in a first-semester general chemistry course, and its effect on attrition was assessed. Attrition from sections before implementing TBL (fall 2008 to fall 2009) was compared with…

  1. A Model for Estimation of Rain Rate on Tropical Land from TRMM Microwave Imager Radiometer Observations

    Science.gov (United States)

    Prabhakara, C.; Iacovazzi, R., Jr.; Yoo, J.-M.; Kim, Kyu-Myong

    2004-01-01

    Over the tropical land regions observations of the 85 GHz brightness temperature (T(sub 85v)) made by the TRMM Microwave Imager (TMI) radiometer when analyzed with the help of rain rate (R(sub pR)) deduced from the TRMM Precipitation Radar (PR) indicate that there are two maxima in rain rate. One strong maximum occurs when T(sub 85) has a value of about 220 K and the other weaker one when T(sub 85v) is much colder approx. 150 K. Together with the help of earlier studies based on airborne Doppler Radar observations and radiative transfer theoretical simulations, we infer the maximum near 220 K is a result of relatively weak scattering due to super cooled rain drops and water coated ice hydrometeors associated with a developing thunderstorm (Cb) that has a strong updraft. The other maximum is associated with strong scattering due to ice particles that are formed when the updraft collapses and the rain from the Cb is transit2oning from convective type to stratiform type. Incorporating these ideas and with a view to improve the estimation of rain rate from existing operational method applicable to the tropical land areas, we have developed a rain retrieval model. This model utilizes two parameters, that have a horizontal scale of approx. 20km, deduced from the TMI measurements at 19, 21 and 37 GHz (T(sub 19v), T(sub 21v), T(sub 37v). The third parameter in the model, namely the horizontal gradient of brightness temperature within the 20 km scale, is deduced from TMI measurements at 85 GHz. Utilizing these parameters our retrieval model is formulated to yield instantaneous rain rate on a scale of 20 km and seasonal average on a mesoscale that agree well with that of the PR.

  2. A Conceptual Framework for Evaluating Attrition in Online Courses

    Science.gov (United States)

    Laing, C. Linda; Laing, Gregory K.

    2015-01-01

    The purpose of this paper is to develop a conceptual framework that considers the role that the sense of isolation and alienation play in contributing to attrition in online courses in the higher education sector. The approach adopted in this paper is a theoretical study aimed at synthesizing existing theories. The ultimate contribution of this…

  3. Attrition, burnout, job dissatisfaction and occupational therapy managers.

    Science.gov (United States)

    Kraeger, M M; Walker, K F

    1992-01-01

    At a time when there is growing concern about the person-power shortages in occupational therapy, there is a need to address reasons why therapists leave the job market. Two job-related reasons for attrition are burnout and job dissatisfaction. The burnout phenomenon occurs as a result of personnel shortages, high-stress demands on therapists, the severity and complexity of client's problems, and the therapist's own ''worker personality.'' Bureaucratic constraints, limited advancement, issues related to a profession which is made up predominantly of women, lack of autonomy, and type of management and supervision are factors that contribute to job dissatisfaction. Occupational therapy managers can consider the causes of burnout and job dissatisfaction and initiate resources to retain therapists. Managers can increase the job benefits, such as flexible working hours, take steps to reduce stress in the workplace, offer career laddering opportunities, and promote staff development. By identifying the causes for attrition and by addressing those causes, the threat of losing therapists from the work force may be averted. Respondents (n = 106) to a survey of occupational therapy managers indicated that job dissatisfaction, burnout, and attrition of registered occupational therapists were not major problems in their settings. They reported a variety of strategies to reduce job dissatisfaction, burnout, and attrition. When these problems were present, managers cited bureaucratic red tape, lack of opportunity for advancement, and increasing role demands as contributing factors.

  4. Evaluation of the Dehulling Efficiency of Soybean Using Attrition and ...

    African Journals Online (AJOL)

    Conditioned seeds were dehulled in the huller section of commercial rice milling machine and attrition milling machine. A dehulling efficiency (e) value of 55%, which corresponded to an extraction yield (E) of 44% was achieved using the huller section of a commercial rice milling machine, while 90% dehulling efficiency (e), ...

  5. Texas Public School Attrition Study, 2013-14. IDRA Report

    Science.gov (United States)

    Johnson, Roy L.; Montes, Felix

    2014-01-01

    Since 1986, Intercultural Development Research Association (IDRA) has conducted an annual attrition study to track the number and percent of students in Texas who are lost from public secondary school enrollment prior to graduation. The study builds on the series of studies that began when IDRA conducted the first comprehensive study of school…

  6. Texas Public School Attrition Study, 2016-17. IDRA Report

    Science.gov (United States)

    Johnson, Roy L.; Montes, Felix

    2017-01-01

    Since 1986, Intercultural Development Research Association (IDRA) has conducted an annual attrition study to track the number and percent of students in Texas who are lost from public secondary school enrollment prior to graduation. The study builds on the series of studies that began when IDRA conducted the first comprehensive study of school…

  7. Texas Public School Attrition Study, 2014-15. IDRA Report

    Science.gov (United States)

    Johnson, Roy L.; Montes, Felix

    2015-01-01

    Since 1986, Intercultural Development Research Association (IDRA) has conducted an annual attrition study to track the number and percent of students in Texas who are lost from public secondary school enrollment prior to graduation. The study builds on the series of studies that began when IDRA conducted the first comprehensive study of school…

  8. Texas Public School Attrition Study, 2015-16. IDRA Report

    Science.gov (United States)

    Johnson, Roy L.; Montes, Felix; Hinojosa, David

    2016-01-01

    Since 1986, Intercultural Development Research Association (IDRA) has conducted an annual attrition study to track the number and percent of students in Texas who are lost from public secondary school enrollment prior to graduation. The study builds on the series of studies that began when IDRA conducted the first comprehensive study of school…

  9. Attrition of Women Business Majors in an Urban Community College.

    Science.gov (United States)

    Karlen, Janice M.

    2004-01-01

    Identified intervention protocols that could help reduce the attrition of women business majors at an urban community college. Review of academic progress data and data from student surveys which examined students' reasons for leaving the institution indicated that there was a need for support mechanisms throughout the freshman year and extending…

  10. The Effects of Turnover: What We Know about Teacher Attrition

    Science.gov (United States)

    DeAngelis, Karen

    2012-01-01

    School business officials are likely to know better than anyone else about the financial costs to districts and schools associated with teacher attrition. Perhaps less well-known, though, is what else has been learned about this issue in recent years--information that may affect how one thinks about teacher turnover. Here is some of that research:…

  11. Teacher Attrition Variables That Influence Retention and Job Satisfaction

    Science.gov (United States)

    Butler, Leslie Garmon

    2014-01-01

    Teacher attrition is a major problem. According to researchers at North Carolina State University, more teachers are leaving the profession than staying or entering. Accordingly, school systems in the United States find themselves in the predicament where they must hire teachers who have little teaching experience or who have not been adequately…

  12. The Career Officer Attrition Dilemma: An Underlying Cause

    Science.gov (United States)

    2002-04-09

    BOOMER, XER, & MILLENIAL TRAITS COMPARISON ..................................... 23 vii viii THE CAREER OFFICER ATTRITION DILEMMA: AN UNDERLYING...provide a sustainable solution. Multiple generations in the military will always be present. What will change, however, is which generation will be in the... MILLENIAL TRAITS COMPARISON cause serious frustration both for the senior leadership and their subordinates. Even as the Xers begin to take over from

  13. Evolutionary dynamics of a smoothed war of attrition game.

    Science.gov (United States)

    Iyer, Swami; Killingback, Timothy

    2016-05-07

    In evolutionary game theory the War of Attrition game is intended to model animal contests which are decided by non-aggressive behavior, such as the length of time that a participant will persist in the contest. The classical War of Attrition game assumes that no errors are made in the implementation of an animal׳s strategy. However, it is inevitable in reality that such errors must sometimes occur. Here we introduce an extension of the classical War of Attrition game which includes the effect of errors in the implementation of an individual׳s strategy. This extension of the classical game has the important feature that the payoff is continuous, and as a consequence admits evolutionary behavior that is fundamentally different from that possible in the original game. We study the evolutionary dynamics of this new game in well-mixed populations both analytically using adaptive dynamics and through individual-based simulations, and show that there are a variety of possible outcomes, including simple monomorphic or dimorphic configurations which are evolutionarily stable and cannot occur in the classical War of Attrition game. In addition, we study the evolutionary dynamics of this extended game in a variety of spatially and socially structured populations, as represented by different complex network topologies, and show that similar outcomes can also occur in these situations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Spacecraft Angular Rates Estimation with Gyrowheel Based on Extended High Gain Observer

    Directory of Open Access Journals (Sweden)

    Xiaokun Liu

    2016-04-01

    Full Text Available A gyrowheel (GW is a kind of electronic electric-mechanical servo system, which can be applied to a spacecraft attitude control system (ACS as both an actuator and a sensor simultaneously. In order to solve the problem of two-dimensional spacecraft angular rate sensing as a GW outputting three-dimensional control torque, this paper proposed a method of an extended high gain observer (EHGO with the derived GW mathematical model to implement the spacecraft angular rate estimation when the GW rotor is working at large angles. For this purpose, the GW dynamic equation is firstly derived with the second kind Lagrange method, and the relationship between the measurable and unmeasurable variables is built. Then, the EHGO is designed to estimate and calculate spacecraft angular rates with the GW, and the stability of the designed EHGO is proven by the Lyapunov function. Moreover, considering the engineering application, the effect of measurement noise in the tilt angle sensors on the estimation accuracy of the EHGO is analyzed. Finally, the numerical simulation is performed to illustrate the validity of the method proposed in this paper.

  15. The assessment of cognitive errors using an observer-rated method.

    Science.gov (United States)

    Drapeau, Martin

    2014-01-01

    Cognitive Errors (CEs) are a key construct in cognitive behavioral therapy (CBT). Integral to CBT is that individuals with depression process information in an overly negative or biased way, and that this bias is reflected in specific depressotypic CEs which are distinct from normal information processing. Despite the importance of this construct in CBT theory, practice, and research, few methods are available to researchers and clinicians to reliably identify CEs as they occur. In this paper, the author presents a rating system, the Cognitive Error Rating Scale, which can be used by trained observers to identify and assess the cognitive errors of patients or research participants in vivo, i.e., as they are used or reported by the patients or participants. The method is described, including some of the more important rating conventions to be considered when using the method. This paper also describes the 15 cognitive errors assessed, and the different summary scores, including valence of the CEs, that can be derived from the method.

  16. A variational technique to estimate snowfall rate from coincident radar, snowflake, and fall-speed observations

    Science.gov (United States)

    Cooper, Steven J.; Wood, Norman B.; L'Ecuyer, Tristan S.

    2017-07-01

    Estimates of snowfall rate as derived from radar reflectivities alone are non-unique. Different combinations of snowflake microphysical properties and particle fall speeds can conspire to produce nearly identical snowfall rates for given radar reflectivity signatures. Such ambiguities can result in retrieval uncertainties on the order of 100-200 % for individual events. Here, we use observations of particle size distribution (PSD), fall speed, and snowflake habit from the Multi-Angle Snowflake Camera (MASC) to constrain estimates of snowfall derived from Ka-band ARM zenith radar (KAZR) measurements at the Atmospheric Radiation Measurement (ARM) North Slope Alaska (NSA) Climate Research Facility site at Barrow. MASC measurements of microphysical properties with uncertainties are introduced into a modified form of the optimal-estimation CloudSat snowfall algorithm (2C-SNOW-PROFILE) via the a priori guess and variance terms. Use of the MASC fall speed, MASC PSD, and CloudSat snow particle model as base assumptions resulted in retrieved total accumulations with a -18 % difference relative to nearby National Weather Service (NWS) observations over five snow events. The average error was 36 % for the individual events. Use of different but reasonable combinations of retrieval assumptions resulted in estimated snowfall accumulations with differences ranging from -64 to +122 % for the same storm events. Retrieved snowfall rates were particularly sensitive to assumed fall speed and habit, suggesting that in situ measurements can help to constrain key snowfall retrieval uncertainties. More accurate knowledge of these properties dependent upon location and meteorological conditions should help refine and improve ground- and space-based radar estimates of snowfall.

  17. Assessing conflict communication in couples: comparing the validity of self-report, partner-report, and observer ratings.

    Science.gov (United States)

    Sanford, Keith

    2010-04-01

    This study of married couples investigated the short-term predictive validity of the partner-report and self-report scales of the Conflict Communication Inventory and compared the validity of these scales with the validity of observer ratings. A sample of 83 married couples completed two problem-solving conversations. Self-report, partner-report, and observer ratings from Conversation 1 were used to predict behavior in Conversation 2, as rated by a separate panel of observers. The short-term predictive validity of partner-report ratings was extremely high and indistinguishable from the validity of observer ratings. Self-report ratings also demonstrated good validity, albeit slightly lower than other methods. Both partner-report and self-report scores explained a substantial amount of variance in concurrent observer ratings of communication after controlling for relationship satisfaction. 2010 APA, all rights reserved

  18. THE OBSERVED RELATION BETWEEN STELLAR MASS, DUST EXTINCTION, AND STAR FORMATION RATE IN LOCAL GALAXIES

    International Nuclear Information System (INIS)

    Zahid, H. J.; Kewley, L. J.; Kudritzki, R. P.; Yates, R. M.

    2013-01-01

    In this study, we investigate the relation between stellar mass, dust extinction, and star formation rate (SFR) using ∼150,000 star-forming galaxies from SDSS DR7. We show that the relation between dust extinction and SFR changes with stellar mass. For galaxies at the same stellar mass, dust extinction is anti-correlated with the SFR at stellar masses 10 M ☉ . There is a sharp transition in the relation at a stellar mass of 10 10 M ☉ . At larger stellar masses, dust extinction is positively correlated with the SFR for galaxies at the same stellar mass. The observed relation between stellar mass, dust extinction, and SFR presented in this study helps to confirm similar trends observed in the relation between stellar mass, metallicity, and SFR. The relation reported in this study provides important new constraints on the physical processes governing the chemical evolution of galaxies. The correlation between SFR and dust extinction for galaxies with stellar masses >10 10 M ☉ is shown to extend to the population of quiescent galaxies suggesting that the physical processes responsible for the observed relation between stellar mass, dust extinction, and SFR may be related to the processes leading to the shutdown of star formation in galaxies.

  19. THE OBSERVED RELATION BETWEEN STELLAR MASS, DUST EXTINCTION, AND STAR FORMATION RATE IN LOCAL GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Zahid, H. J.; Kewley, L. J.; Kudritzki, R. P. [Institute for Astronomy, University of Hawaii at Manoa, 2680 Woodlawn Dr., Honolulu, HI 96822 (United States); Yates, R. M. [Max-Planck-Institute for Astrophysics, Karl-Schwarzschild-Str. 1, D-85741 Garching (Germany)

    2013-02-15

    In this study, we investigate the relation between stellar mass, dust extinction, and star formation rate (SFR) using {approx}150,000 star-forming galaxies from SDSS DR7. We show that the relation between dust extinction and SFR changes with stellar mass. For galaxies at the same stellar mass, dust extinction is anti-correlated with the SFR at stellar masses <10{sup 10} M {sub Sun }. There is a sharp transition in the relation at a stellar mass of 10{sup 10} M {sub Sun }. At larger stellar masses, dust extinction is positively correlated with the SFR for galaxies at the same stellar mass. The observed relation between stellar mass, dust extinction, and SFR presented in this study helps to confirm similar trends observed in the relation between stellar mass, metallicity, and SFR. The relation reported in this study provides important new constraints on the physical processes governing the chemical evolution of galaxies. The correlation between SFR and dust extinction for galaxies with stellar masses >10{sup 10} M {sub Sun} is shown to extend to the population of quiescent galaxies suggesting that the physical processes responsible for the observed relation between stellar mass, dust extinction, and SFR may be related to the processes leading to the shutdown of star formation in galaxies.

  20. The increase in fatigue crack growth rates observed for Zircaloy-4 in a PWR environment

    Science.gov (United States)

    Cockeram, B. V.; Kammenzind, B. F.

    2018-02-01

    Cyclic stresses produced during the operation of nuclear reactors can result in the extension of cracks by processes of fatigue. Although fatigue crack growth rate (FCGR) data for Zircaloy-4 in air are available, little testing has been performed in a PWR primary water environment. Test programs have been performed by Gee et al., in 1989 and Picker and Pickles in 1984 by the UK Atomic Energy Authority, and by Wisner et al., in 1994, that have shown an enhancement in FCGR for Zircaloy-2 and Zircaloy-4 in high-temperature water. In this work, FCGR testing is performed on Zircaloy-4 in a PWR environment in the hydrided and non-hydrided condition over a range of stress-intensity. Measurements of crack extension are performed using a direct current potential drop (DCPD) method. The cyclic rate in the PWR primary water environment is varied between 1 cycle per minute to 0.1 cycle per minute. Faster FCGR rates are observed in water in comparison to FCGR testing performed in air for the hydrided material. Hydrided and non-hydrided materials had similar FCGR values in air, but the non-hydrided material exhibited much lower rates of FCGR in a PWR primary water environment than for hydrided material. Hydrides are shown to exhibit an increased tendency for cracking or decohesion in a PWR primary water environment that results in an enhancement in FCGR values. The FCGR in the PWR primary water only increased slightly with decreasing cycle frequency in the range of 1 cycle per minute to 0.1 cycle per minute. Comparisons between the FCGR in water and air show the enhancement from the PWR environment is affected by the applied stress intensity.

  1. Within country inequalities in caesarean section rates: observational study of 72 low and middle income countries.

    Science.gov (United States)

    Boatin, Adeline Adwoa; Schlotheuber, Anne; Betran, Ana Pilar; Moller, Ann-Beth; Barros, Aluisio J D; Boerma, Ties; Torloni, Maria Regina; Victora, Cesar G; Hosseinpoor, Ahmad Reza

    2018-01-24

    To provide an update on economic related inequalities in caesarean section rates within countries. Secondary analysis of demographic and health surveys and multiple indicator cluster surveys. 72 low and middle income countries with a survey conducted between 2010 and 2014 for analysis of the latest situation of inequality, and 28 countries with a survey also conducted between 2000 and 2004 for analysis of the change in inequality over time. Women aged 15-49 years with a live birth during the two or three years preceding the survey. Data on caesarean section were disaggregated by asset based household wealth status and presented separately for five subgroups, ranging from the poorest to the richest fifth. Absolute and relative inequalities were measured using difference and ratio measures. The pace of change in the poorest and richest fifths was compared using a measure of excess change. National caesarean section rates ranged from 0.6% in South Sudan to 58.9% in the Dominican Republic. Within countries, caesarean section rates were lowest in the poorest fifth (median 3.7%) and highest in the richest fifth (median 18.4%). 18 out of 72 study countries reported a difference of 20 percentage points or higher between the richest and poorest fifth. The highest caesarean section rates and greatest levels of absolute inequality were observed in countries from the region of the Americas, whereas countries from the African region had low levels of caesarean use and comparatively lower levels of absolute inequality, although relative inequality was quite high in some countries. 26 out of 28 countries reported increases in caesarean section rates over time. Rates tended to increase faster in the richest fifth (median 0.9 percentage points per year) compared with the poorest fifth (median 0.2 percentage points per year), indicating an increase in inequality over time in most of these countries. Substantial within country economic inequalities in caesarean deliveries remain

  2. Attrition in longitudinal randomized controlled trials: home visits make a difference

    Directory of Open Access Journals (Sweden)

    Peterson Janey C

    2012-11-01

    Full Text Available Abstract Background Participant attrition in longitudinal studies can introduce systematic bias, favoring participants who return for follow-up, and increase the likelihood that those with complications will be underestimated. Our aim was to examine the effectiveness of home follow-up (Home F/U to complete the final study evaluation on potentially “lost” participants by: 1 evaluating the impact of including and excluding potentially “lost” participants (e.g., those who required Home F/U to complete the final evaluation on the rates of study complications; 2 examining the relationship between timing and number of complications on the requirement for subsequent Home F/U; and 3 determining predictors of those who required Home F/U. Methods We used data from a randomized controlled trial (RCT conducted from 1991–1994 among coronary artery bypass graft surgery patients that investigated the effect of High mean arterial pressure (MAP (intervention vs. Low MAP (control during cardiopulmonary bypass on 5 complications: cardiac morbidity/mortality, neurologic morbidity/mortality, all-cause mortality, neurocognitive dysfunction and functional decline. We enhanced completion of the final 6-month evaluation using Home F/U. Results Among 248 participants, 61 (25% required Home F/U and the remaining 187 (75% received Routine F/U. By employing Home F/U, we detected 11 additional complications at 6 months: 1 major neurologic complication, 6 cases of neurocognitive dysfunction and 4 cases of functional decline. Follow-up of 61 additional Home F/U participants enabled us to reach statistical significance on our main trial outcome. Specifically, the High MAP group had a significantly lower rate of the Combined Trial Outcome compared to the Low MAP group, 16.1% vs. 27.4% (p=0.032. In multivariate analysis, participants who were ≥ 75 years (OR=3.23, 95% CI 1.52-6.88, p=0.002 or on baseline diuretic therapy (OR=2.44, 95% CI 1.14-5.21, p=0.02 were more

  3. Particle deposition from aqueous suspensions in turbulent pipe flow - a comparison of observed deposition rates and predicted arrival rates

    International Nuclear Information System (INIS)

    Rodliffe, R.S.

    1979-11-01

    At the present time, there appear to be only four adequately controlled and characterised experimental studies of particle deposition from single phase water in turbulent pipe flow. These are used to illustrate the ranges of applicability of methods for predicting particle arrival rates at tube walls. Arrival rates are predicted from mass transfer correlations and the theory of Reeks and Skyrme (1976) when transport is limited by Brownian diffusion and inertial behaviour, respectively. The regimes in which finite particle size limits the application of these methods are defined and preliminary consideration is given to the conditions under which gravitational settling may make a contribution to deposition in vertically mounted tubes. (author)

  4. Observations of the turbulent kinetic energy dissipation rate in the upper central South China Sea

    Science.gov (United States)

    Liang, Chang-Rong; Chen, Gui-Ying; Shang, Xiao-Dong

    2017-05-01

    Measurements of the turbulent kinetic energy dissipation rate ( ɛ), velocity, temperature, and salinity were obtained for the upper ocean of the central South China Sea (14.5° N, 117.0° E) during an experimental campaign from May 11 to 13, 2010. Dissipation in the diurnal mixed layer showed a diurnal variability that was strongly affected by the surface buoyancy flux. Dissipation was enhanced ( ɛ ˜ 10-7 W kg-1) at night due to the convective mixing and was weakened ( ɛ ˜ 10-9 W kg-1) in daytime due to the stratification. Dissipation in the thermocline varied with time under the influence of internal waves. Shear from high-frequency internal waves (period ˜8 h) played an important role in enhancing the turbulent mixing in the thermocline. In the period of strong high-frequency internal waves, the shear from high-frequency internal waves became strong and the depth-averaged ɛ in the thermocline was elevated by almost one order of magnitude. Compared with the dissipation in the thermocline, dissipation below was weaker (the time-averaged ɛ ˜ 10-10 W kg-1). The observation indicates that the dissipation rates during the measurements can be parameterized by the MacKinnon-Gregg model that is widely used in the continental shelf but are not in agreement with the Gregg-Henyey model used for the open ocean.

  5. Attrition of memory CD8 T cells during sepsis requires LFA-1.

    Science.gov (United States)

    Serbanescu, Mara A; Ramonell, Kimberly M; Hadley, Annette; Margoles, Lindsay M; Mittal, Rohit; Lyons, John D; Liang, Zhe; Coopersmith, Craig M; Ford, Mandy L; McConnell, Kevin W

    2016-11-01

    CD8 T cell loss and dysfunction have been implicated in the increased susceptibility to opportunistic infections during the later immunosuppressive phase of sepsis, but CD8 T cell activation and attrition in early sepsis remain incompletely understood. With the use of a CLP model, we assessed CD8 T cell activation at 5 consecutive time points and found that activation after sepsis results in a distinct phenotype (CD69 + CD25 int CD62L HI ) independent of cognate antigen recognition and TCR engagement and likely through bystander-mediated cytokine effects. Additionally, we observed that sepsis concurrently results in the preferential depletion of a subset of memory-phenotype CD8 T cells that remain "unactivated" (i.e., fail to up-regulate activation markers) by apoptosis. Unactivated CD44 HI OT-I cells were spared from sepsis-induced attrition, as were memory-phenotype CD8 T cells of mice treated with anti-LFA-1 mAb, 1 h after CLP. Perhaps most importantly, we demonstrate that attrition of memory phenotype cells may have a pathologic significance, as elevated IL-6 levels were associated with decreased numbers of memory-phenotype CD8 T cells in septic mice, and preservation of this subset after administration of anti-LFA-1 mAb conferred improved survival at 7 d. Taken together, these data identify potentially modifiable responses of memory-phenotype CD8 T cells in early sepsis and may be particularly important in the application of immunomodulatory therapies in sepsis. © Society for Leukocyte Biology.

  6. Observer-rated depression in long-term care: frequency and risk factors.

    Science.gov (United States)

    McCusker, Jane; Cole, Martin G; Voyer, Philippe; Monette, Johanne; Champoux, Nathalie; Ciampi, Antonio; Vu, Minh; Dyachenko, Alina; Belzile, Eric

    2014-01-01

    The objectives of this study were: (1) to describe the prevalence and 6-month incidence of observer-rated depression in residents age 65 and over of long-term care (LTC) facilities; (2) to describe risk factors for depression, at baseline and over time. A multisite, prospective observational study was conducted in residents aged 65 and over of 7 LTC facilities. The Cornell Scale for Depression in Dementia (CSDD) was completed by nurses monthly for 6 months. We measured demographic, medical, and functional factors at baseline and monthly intervals, using data from research assessments, nurse interviews, and chart reviews. 274 residents were recruited and completed baseline depression assessments. The prevalence of depression (CSDD score of 6+) was 19.0%. The incidence of depression among those without prevalent depression was 73.3 per 100 person-years. A delirium diagnosis, pain, and diabetes were independently associated with prevalent depression. CSDD score at baseline and development of severe cognitive impairment at follow-up were independent risk factors for incident depression. A diagnosis of delirium and uncorrected visual impairment at follow-up occurred concurrently with incident depression. The results of this study have implications for the detection and prevention of depression in LTC. Delirium diagnosis, pain and diabetes at baseline were associated with prevalent depression; depression symptoms at baseline and development of severe cognitive impairment at follow-up were risk factors for incident depression. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  7. Optimally decoding the input rate from an observation of the interspike intervals

    Energy Technology Data Exchange (ETDEWEB)

    Feng Jianfeng [COGS, University of Sussex at Brighton (United Kingdom) and Computational Neuroscience Laboratory, Babraham Institute, Cambridge (United Kingdom)]. E-mail: jf218@cam.ac.uk

    2001-09-21

    A neuron extensively receives both inhibitory and excitatory inputs. What is the ratio r between these two types of input so that the neuron can most accurately read out input information (rate)? We explore the issue in this paper provided that the neuron is an ideal observer - decoding the input information with the attainment of the Cramer-Rao inequality bound. It is found that, in general, adding certain amounts of inhibitory inputs to a neuron improves its capability of accurately decoding the input information. By calculating the Fisher information of an integrate-and-fire neuron, we determine the optimal ratio r for decoding the input information from an observation of the efferent interspike intervals. Surprisingly, the Fisher information can be zero for certain values of the ratio, seemingly implying that it is impossible to read out the encoded information at these values. By analysing the maximum likelihood estimate of the input information, it is concluded that the input information is in fact most easily estimated at the points where the Fisher information vanishes. (author)

  8. Observations and simulations of snowpack cold content and its relationship to snowmelt timing and rate

    Science.gov (United States)

    Jennings, K. S.; Molotch, N. P.

    2017-12-01

    Mountain snowpacks serve as a vital water resource for more than 1 billion people across the globe. Two key properties of snowmelt—rate and timing—are controlled by the snowpack energy budget where incoming positive fluxes are balanced by a decrease in the energy deficit of the snowpack and a change in the phase of water from solid to liquid. In this context, the energy deficit, or cold content, regulates snowmelt as runoff does not commence until the deficit approaches zero. There is significant uncertainty surrounding cold content despite its relevance to snowmelt processes, likely due to the inherent difficulties in its observation. Our work has clarified the previously unresolved meteorological and energy balance controls on cold content development in seasonal snowpacks by leveraging two unique datasets from the Niwot Ridge LTER in the Rocky Mountains of Colorado. The first is a long-term snow pit record of snowpack properties from an alpine and subalpine site within the LTER. These data were augmented with a 23-year simulation of the snowpack at both sites using a quality controlled, serially complete, hourly forcing dataset. The observations and simulations both indicated that cold content primarily developed through new snowfall, while a negative energy budget provided a secondary pathway for cold content development, mainly through longwave emission and sublimation. Cold content gains from snowfall outnumbered energy balance gains by 438% in the alpine and 166% in the subalpine. Increased spring precipitation and later peak cold content significantly delayed snowmelt onset and daily melt rates were reduced by 32.2% in the alpine and 36.1% in the subalpine when an energy deficit needed to be satisfied. Furthermore, preliminary climate change simulations indicated warmer air temperatures reduced cold content accumulation, which increased the amount of snow lost to melt throughout the winter as incoming positive fluxes had to overcome smaller energy

  9. Observational and Genetic Associations of Resting Heart Rate With Aortic Valve Calcium.

    Science.gov (United States)

    Whelton, Seamus P; Mauer, Andreas C; Pencina, Karol M; Massaro, Joseph M; D'Agostino, Ralph B; Fox, Caroline S; Hoffmann, Udo; Michos, Erin D; Peloso, Gina M; Dufresne, Line; Engert, James C; Kathiresan, Sekar; Budoff, Matthew; Post, Wendy S; Thanassoulis, George; O'Donnell, Christopher J

    2018-05-15

    It is unknown if lifelong exposure to increased hemodynamic stress from an elevated resting heart rate (HR) may contribute to aortic valve calcium (AVC). We performed multivariate regression analyses using data from 1,266 Framingham Heart Study (FHS) Offspring cohort participants and 6,764 Multi-Ethnic Study of Atherosclerosis (MESA) participants. We constructed a genetic risk score (GRS) for HR using summary-level data in the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) AVC Consortium to investigate if there was evidence in favor of a causal relation. AVC was present in 39% of FHS Offspring cohort participants and in 13% of MESA cohort participants. In multivariate adjusted models, participants in the highest resting HR quartiles had significantly greater prevalence of AVC, with a prevalence ratio of 1.19 (95% confidence interval [CI] 0.99 to 1.44) for the FHS Offspring cohort and 1.32 (95% CI 1.12 to 1.63) for the MESA cohort, compared with those in the lowest quartile. There was a similar increase in the prevalence of AVC per standard deviation increase in resting HR in both FHS Offspring (prevalence ratio 1.08, 95% CI 1.01 to 1.15) and MESA (1.10, 95% CI 1.03 to 1.17). In contrast with these observational findings, a HR associated GRS was not significantly associated with AVC. Although our observational analysis indicates that a higher resting HR is associated with AVC, our genetic results do not support a causal relation. Unmeasured environmental and/or lifestyle factors associated with both increased resting HR and AVC that are not fully explained by covariates in our observational models may account for the association between resting HR and AVC. Copyright © 2018. Published by Elsevier Inc.

  10. Formation and growth rates of atmospheric nanoparticles: four years of observations at two West Siberian stations

    Science.gov (United States)

    Arshinov, Mikhail Yu.; Belan, Boris D.; Davydov, Denis K.; Kozlov, Artem V.; Arshinova, Victoria

    2015-04-01

    In spite of fact that the first report on the new particle formation (NPF) itself was done by John Aitken more than one century ago (Aitken, 1898), a phenomenon of NPF bursts taken place in the atmosphere was discovered not very long ago. Nevertheless, to date it is known that they may occur quite often in a variety of environments (Kulmala et al., 2004; Hirsikko et al., 2011). Siberia occupies a vast area covered by forests, but the comprehensive data on burst frequency, as well as on formation and growth rates of freshly nucleated particles in this key region are still lacking. Continuous measurements of aerosol size distribution carried out in recent years at two West Siberian stations (TOR-station - 56o28'41"N, 85o03'15"E; Fonovaya Observatory - 56o25'07"N, 84o04'27"E) allowed this gap in data to be filled up. Analysis of the size spectra classified in accordance with criteria proposed by Dal Maso et al. (2005) and Hammed et al. (2007) enabled a conclusion to be drawn that NPF events in Wets Siberia are more often observed during spring (from March to May) and early autumn (secondary frequency peak in September). On average, particle formation bursts took place on 23-28 % of all days. Such a seasonal pattern of the NPF occurrence is very similar to one observed at SMEAR II Station (Hyytiälä, Finland; Dal Maso et al. 2005, 2007). Formation rates (FR) of particles with diameters below 25 nm varied in a wide range from 0.1 to 10 cm-3 s-1. Mean values of FR for the entire period of observations were 1.7 cm-3s-1 (median = 1.13 cm-3 s-1) at TOR-station and 0.88 cm-3 s-1 (median = 0.69 cm-3 s-1) at Fonovaya Observatory. Enhanced values of FR are usually observed from spring to autumn. Mean growth rates of observed at TOR-station and Fonovaya Observatory were 6.5 nm h-1 (median = 5.0 nm h-1) and 8.3 nm h-1 (median = 6.4 nm h-1), respectively. This work was supported by the Branch of Geology, Geophysics and Mining Sciences of RAS (Program No. 5); State contracts of

  11. Attitudes of non-practicing chiropractors: a pilot survey concerning factors related to attrition

    Directory of Open Access Journals (Sweden)

    Wyatt Lawrence H

    2010-11-01

    Full Text Available Abstract Background Research into attitudes about chiropractors who are no longer engaged in active clinical practice is non-existent. Yet non-practicing chiropractors (NPCs represent a valid sub-group worthy of study. Aim The purpose of this research was to assess attrition attitudes of NPCs about the chiropractic profession and develop a scale to assess such attitudes. Methods A 48 item survey was developed using the PsychData software. This survey included 35 Likert-style items assessing various aspects of the profession namely financial, educational, psychosocial and political. An internet discussion site where NPCs may be members was accessed for recruitment purposes. Results A total of 70 valid responses were received for analysis. A majority of respondents were male with 66% being in non-practice status for 3 to 5 years and less with 43% indicating that they had graduated since the year 2000. Most respondents were employed either in other healthcare professions and non-chiropractic education. A majority of NPCs believed that business ethics in chiropractic were questionable and that overhead expense and student loans were factors in practice success. A majority of NPCs were in associate practice at one time with many believing that associates were encouraged to prolong the care of patients and that associate salaries were not fair. Most NPCs surveyed believed that chiropractic was not a good career choice and would not recommend someone to become a chiropractor. From this survey, a 12 item scale was developed called the "chiropractor attrition attitude scale" for future research. Reliability analysis of this novel scale demonstrated a coefficient alpha of 0.90. Conclusion The low response rate indicates that findings cannot be generalized to the NPC population. This study nonetheless demonstrates that NPCs attrition attitudes can be assessed. The lack of a central database of NPCs is a challenge to future research. Appropriate

  12. High attrition among HIV-infected patients with advanced disease treated in an intermediary referral center in Maputo, Mozambique

    Directory of Open Access Journals (Sweden)

    Lucas Molfino

    2014-04-01

    Full Text Available Background: In Mozambique, antiretroviral therapy (ART scale-up has been successfully implemented. However, attrition in care remains a major programmatic challenge. In 2009, an intermediary-level HIV referral center was created in Maputo to ensure access to specialized care for HIV-infected patients with complications (advanced clinical-immunological stage, Kaposi sarcoma, or suspected ART failure. Objective: To determine the attrition from care and to identify risk factors that lead to high attrition among patients referred to an intermediary-level HIV referral center. Design: This was a retrospective cohort study from 2009 to 2011. Results: A total of 1,657 patients were enrolled, 847 (51% were men, the mean age was 36 years (standard deviation: 11, the mean CD4 count was 27 cells/µl (interquartile range: 11–44, and one-third were severely malnourished. The main reasons for referral were advanced clinical stages (WHO stages 3 and 4, and CD4 count <50 cells/µl in 70% of the cases, and 19% had Kaposi sarcoma. The overall attrition rate was 28.7 per 100 person-years (PYs – the mortality rate was 5.0 (95% confidence interval [CI]: 4.2–5.9 per 100 PYs, and the loss-to-follow-up rate was 23.7 (95% CI: 21.9–25.6 per 100 PYs. There were 793 attritions – 137 deaths and 656 lost to follow-up (LTFU; 77% of all attrition happened within the first year. The factors independently associated with attrition were male sex (adjusted hazard ratio [aHR]: 1.15, 95% CI: 1.0–1.3, low body mass index (aHR: 1.51, 95% CI: 1.2–1.8, WHO clinical stage 3 or 4 (aHR: 1.30, 95% CI: 1.0–1.6; and aHR: 1.91, 95% CI: 1.4–2.5, later year of enrollment (aHR 1.61, 95% CI 1.3–1.9, and ‘being already on ART’ at enrollment (aHR 13.71, 95% CI 11.4–16.4. Conclusions: Attrition rates among HIV-infected patients enrolled in an intermediary referral center were high, mainly related to advanced stage of clinical disease. Measures are required to address this

  13. Listen-Identify-Brainstorm-Reality-Test-Encourage (LIBRE) Problem-Solving Model: Addressing Special Education Teacher Attrition through a Cognitive-Behavioral Approach to Teacher Induction

    Science.gov (United States)

    Guerra, Norma S.; Hernandez, Art; Hector, Alison M.; Crosby, Shane

    2015-01-01

    Special education teacher attrition rates continue to challenge the profession. A cognitive-behavioral problem-solving approach was used to examine three alternative certification program special education teachers' professional development through a series of 41 interviews conducted over a 2-year period. Beginning when they were novice special…

  14. Accelerated telomere attrition is associated with relative household income, diet and inflammation in the pSoBid cohort.

    Directory of Open Access Journals (Sweden)

    Paul G Shiels

    Full Text Available It has previously been hypothesized that lower socio-economic status can accelerate biological ageing, and predispose to early onset of disease. This study investigated the association of socio-economic and lifestyle factors, as well as traditional and novel risk factors, with biological-ageing, as measured by telomere length, in a Glasgow based cohort that included individuals with extreme socio-economic differences.A total of 382 blood samples from the pSoBid study were available for telomere analysis. For each participant, data was available for socio-economic status factors, biochemical parameters and dietary intake. Statistical analyses were undertaken to investigate the association between telomere lengths and these aforementioned parameters.The rate of age-related telomere attrition was significantly associated with low relative income, housing tenure and poor diet. Notably, telomere length was positively associated with LDL and total cholesterol levels, but inversely correlated to circulating IL-6.These data suggest lower socio-economic status and poor diet are relevant to accelerated biological ageing. They also suggest potential associations between elevated circulating IL-6, a measure known to predict cardiovascular disease and diabetes with biological ageing. These observations require further study to tease out potential mechanistic links.

  15. 3D analysis of high ozone production rates observed during the ESCOMPTE campaign

    Science.gov (United States)

    Coll, Isabelle; Pinceloup, Stéphanie; Perros, Pascal E.; Laverdet, Gérard; Le Bras, Georges

    2005-03-01

    The development of environmental policies to reduce the ozone levels around large agglomerations requires a good understanding of the development of ozone episodes. In particular, it is necessary to know the location and photochemical activity of the plume where ozone is formed. Measurement campaigns make it possible not only to characterize the concentration fields of ozone and its precursors but also to identify the zones of strong ozone production, by means of specific measurements and kinetic calculations. The combination of the observation-based data with numerical simulations allows to better characterize photochemical pollution. This paper presents a study carried out within the ESCOMPTE program and based on the determination of ozone production rates by experimental and numerical methods: ground measurements of peroxy radicals, NO x at a rural site, airborne measurements of NO X and O 3, Eulerian modeling. The reported case is of particular interest since it corresponds to an episode with very different photochemical situations. The diurnal variations of the peroxy radical concentration are analyzed in relation to those of ozone and its precursors. Ozone production rates— P(O 3)-are studied over one particular day. The results show particularly high concentrations of RO 2+HO 2 at ground level (up to 200 pptv) under the influence of the urban and industrial plume, but also highlight very high production rates of ozone (60 to 80 ppbv h -1) a few tens of kilometers from the sources. The results show satisfactory agreement between the various approaches. Modeling provides a four-dimensional (4D) description of the plumes, in particular the relation between the ozone precursor concentrations and P(O 3) on the ground.

  16. Relationship between Academic Performance, Spatial Competence, Learning Styles and Attrition

    Directory of Open Access Journals (Sweden)

    Marianela Noriega Biggio

    2013-04-01

    Full Text Available This paper discusses the results of research on factors affecting academic performance and attrition in a sample of 1,500 freshman students majoring in architecture, design and urbanism at the Universidad de Buenos Aires, Argentina [University of Buenos Aires, Argentina] who were enrolled in a drafting course. The hypotheses we tested concern the mediating role of learning styles on the relationship between spatial competence and academic performance, learning-style differences by gender and cohort, and the relationship between attrition, spatial competence level and learning style. Statistical analysis of the data was performed and spatial competence enhanced by motivational profile was found to predict final achievement. Educational implications are identified, highlighting the need to promote in students those academic behaviors that characterize a self-regulated learning style and encourage the use of specific intellectual abilities.

  17. Ash production by attrition in volcanic conduits and plumes.

    Science.gov (United States)

    Jones, T J; Russell, J K

    2017-07-17

    Tephra deposits result from explosive volcanic eruption and serve as indirect probes into fragmentation processes operating in subsurface volcanic conduits. Primary magmatic fragmentation creates a population of pyroclasts through volatile-driven decompression during conduit ascent. In this study, we explore the role that secondary fragmentation, specifically attrition, has in transforming primary pyroclasts upon transport in volcanic conduits and plumes. We utilize total grain size distributions from a suite of natural and experimentally produced tephra to show that attrition is likely to occur in all explosive volcanic eruptions. Our experimental results indicate that fine ash production and surface area generation is fast (eruption column stability, tephra dispersal, aggregation, volcanic lightening generation, and has concomitant effects on aviation safety and Earth's climate.

  18. COMPENSATORY STRATEGIES OF FIRST-LANGUAGE-ATTRITED CHILDREN

    Directory of Open Access Journals (Sweden)

    Syahdan Syahdan

    2012-01-01

    Full Text Available This article explores the compensatory strategies used by two Indonesian children who experienced first language attrition when acquiring English in the English-speaking environment. They use compensatory strategies to compensate for their lack of competence in first language. They employ both interlingual strategies and discourse strategies when they have difficulties in communication. Interlingual strategies used are codeswitching and lexical borrowings and the discourse strategies are overt comments, appeal for assistance, and avoidance.

  19. The Impact of Fund Attrition on Superannuation Returns

    OpenAIRE

    Drew, Michael E.; Stanford, Jon D.

    2001-01-01

    This paper investigates the impact of fund attrition on returns from a sample of superannuation fund managers (specialising in the management of domestic stock portfolios) for the period 1991 through 1999, using a four-factor asset pricing model. Survivorship bias is estimated at 23 basis points per annum. The evidence presented in this study is consistent with recent international evidence that suggests that a sampling technique that excludes terminated funds would result in an overestimatio...

  20. Germanic heritage languages in North America: Acquisition, attrition and change

    OpenAIRE

    Johannessen, Janne Bondi; Salmons, Joseph C.; Westergaard, Marit; Anderssen, Merete; Arnbjörnsdóttir, Birna; Allen, Brent; Pierce, Marc; Boas, Hans C.; Roesch, Karen; Brown, Joshua R.; Putnam, Michael; Åfarli, Tor A.; Newman, Zelda Kahan; Annear, Lucas; Speth, Kristin

    2015-01-01

    This book presents new empirical findings about Germanic heritage varieties spoken in North America: Dutch, German, Pennsylvania Dutch, Icelandic, Norwegian, Swedish, West Frisian and Yiddish, and varieties of English spoken both by heritage speakers and in communities after language shift. The volume focuses on three critical issues underlying the notion of ‘heritage language’: acquisition, attrition and change. The book offers theoretically-informed discussions of heritage language processe...

  1. Predictors of Attrition in the Finnish Conscript Service

    Science.gov (United States)

    2006-11-01

    Dawson et al., 1994; Kassel, Jackson, & Unrod, 2000; Lazarus & Folkman , 1984; Pierce & Lydon, 1998; Thompson & Gignac, 2001). These expectations toward...organizational socialization. USAWC Strategy Research Project Carlisle Barracks, PA: U.S. Army War College. Hicks, J. M., & Nogami, G. Y . (1984...of Navy attrition. II. A demonstration of potential usefulness for screening. (Report No. 01-06). Military Medicine, 167, 770-776. Lazarus , R. S

  2. Assessment of Measurement Tools of Observation Rate of Nursing Handover Standards in Clinical Wards of Hospital

    Directory of Open Access Journals (Sweden)

    Saadi Amini

    2015-08-01

    Full Text Available Background and objectives : In health centers, clinical information of patient is transferred among care staffs regularly. One of the common cases in information transferring is during the time of nurses’ handover in hospital which performing it correctly will help schedule patient care, providing safety and facilitating exact transferring of information. The aim of this study is investigating validity and reliability of assessment of observance rate of shift handover in clinical wards checklist. Material and Methods : In order to determine the reliability of checklist, two experts panel meetings were held with the presence of 10 experts in clinical field that in those meetings the reliability was investigated with discussion and consensus of participants. Checklist validity was investigated through pilot study in 4 wards of 4 hospitals and calculated by Kronbach- alpha method with 28 cases of shifts handover in morning, noon, and night shift. Results : In studying reliability, the primary checklist was divided into two checklists: patient handover, equipments and ward handover that included 27 and 72 items, respectively. The reliability of patient handover checklist was verified with 0.9155 Kronbach-alpha and that of equipments and ward handover was verified with 0.8779 Kronbach-alpha. Conclusion : Verifying checklists by mentioned scientific and statistical methods showed that these are very powerful instruments that can be used as one of the assessment tools of shift handover in clinical wards to be used towards promoting received services by customers of healthcare system.

  3. Taking into account the impact of attrition on the assessment of response shift and true change: a multigroup structural equation modeling approach.

    Science.gov (United States)

    Verdam, Mathilde G E; Oort, Frans J; van der Linden, Yvette M; Sprangers, Mirjam A G

    2015-03-01

    Missing data due to attrition present a challenge for the assessment and interpretation of change and response shift in HRQL outcomes. The objective was to handle such missingness and to assess response shift and 'true change' with the use of an attrition-based multigroup structural equation modeling (SEM) approach. Functional limitations and health impairments were measured in 1,157 cancer patients, who were treated with palliative radiotherapy for painful bone metastases, before [time (T) 0], every week after treatment (T1 through T12), and then monthly for up to 2 years (T13 through T24). To handle missing data due to attrition, the SEM procedure was extended to a multigroup approach, in which we distinguished three groups: short survival (3-5 measurements), medium survival (6-12 measurements), and long survival (>12 measurements). Attrition after third, sixth, and 13th measurement occasions was 11, 24, and 41 %, respectively. Results show that patterns of change in functional limitations and health impairments differ between patients with short, medium, or long survival. Moreover, three response-shift effects were detected: recalibration of 'pain' and 'sickness' and reprioritization of 'physical functioning.' If response-shift effects would not have been taken into account, functional limitations and health impairments would generally be underestimated across measurements. The multigroup SEM approach enables the analysis of data from patients with different patterns of missing data due to attrition. This approach does not only allow for detection of response shift and assessment of true change across measurements, but also allow for detection of differences in response shift and true change across groups of patients with different attrition rates.

  4. Attrition Resistant Fischer-Tropsch Catalysts Based on FCC Supports

    Energy Technology Data Exchange (ETDEWEB)

    Adeyiga, Adeyinka

    2010-02-05

    Commercial spent fluid catalytic cracking (FCC) catalysts provided by Engelhard and Albemarle were used as supports for Fe-based catalysts with the goal of improving the attrition resistance of typical F-T catalysts. Catalysts with the Ruhrchemie composition (100 Fe/5 Cu/4.2 K/25 spent FCC on mass basis) were prepared by wet impregnation. XRD and XANES analysis showed the presence of Fe{sub 2}O{sub 3} in calcined catalysts. FeC{sub x} and Fe{sub 3}O{sub 4} were present in the activated catalysts. The metal composition of the catalysts was analyzed by ICP-MS. F-T activity of the catalysts activated in situ in CO at the same conditions as used prior to the attrition tests was measured using a fixed bed reactor at T = 573 K, P = 1.38 MPa and H{sub 2}:CO ratio of 0.67. Cu and K promoted Fe supported over Engelhard provided spent FCC catalyst shows relatively good attrition resistance (8.2 wt% fines lost), high CO conversion (81%) and C{sub 5}+ hydrocarbons selectivity (18.3%).

  5. Favorable bed utilization and readmission rates for emergency department observation unit heart failure patients.

    Science.gov (United States)

    Schrager, Justin; Wheatley, Matthew; Georgiopoulou, Vasiliki; Osborne, Anwar; Kalogeropoulos, Andreas; Hung, Olivia; Butler, Javed; Ross, Michael

    2013-06-01

    The objective was to compare readmission rates and hospital bed-days between acute decompensated heart failure (AHF) patients admitted or discharged following accelerated treatment protocol (ATP)-driven care in an emergency department observation unit (OU). This was a retrospective cohort study conducted at two urban university-affiliated hospitals. A total of 358 selected AHF patients received treatment on an ATP in the OU between October 1, 2007, and June 30, 2011. The comparison of interest was admission or discharge following OU treatment. The outcome of interest was readmission within 30 and 90 days of hospital discharge following care in the OU. We also examined resource use (inpatient, inpatient plus outpatient-days) between the admitted and discharged groups. Time to readmission analysis was performed with Cox proportional hazards regression. Discharged and admitted patients were similar with respect to age, race, sex, ED length of stay (LOS), and OU LOS. Patients admitted from the OU had a higher median B-type natriuretic peptide (BNP; 1,063 pg/mL [interquartile range {IQR} = 552 to 2,067 pg/mL] vs. 708 pg/mL [IQR = 254 to 1,683 pg/mL]; p = 0.002) and blood urea nitrogen (BUN; 19 mg/dL [IQR = 14 to 26 mg/dL] vs. 17 mg/dL [IQR = 13 to 23 mg/dL]) than those discharged (p = 0.04) and a lower median ejection fraction (EF; 22.5% [15% to 43%] vs. 35% [IQR 20% to 55%]; p = 0.002). In models controlling for age, race, sex, clinical site, BNP, BUN, creatinine, and EF, the 30-day readmission rate (13.8% in the study population as a whole) was not significantly different between the patients discharged or admitted following OU care (hazard ratio [HR] = 0.99; 95% confidence interval [CI] = 0.47 to 2.10). The readmission rates were also not significantly different at 90 days (HR = 1.07; 95% CI = 0.65 to 1.77). Within 30 days of discharge from the OU, patients spent a median of 1.7 days (IQR = 0.0 to 5.1 days) as inpatients, compared to 3.5 days (IQR = 2.3 to 5.8 days

  6. Heart rate awareness in patients with chronic stable heart failure. A multi-center observational study.

    LENUS (Irish Health Repository)

    Moran, D

    2014-08-23

    We assessed adherence to European Society of Cardiology heart rate guidelines (i.e. heart rates less than 70bpm) in patients with chronic stable heart failure. We also investigated the percent of patients on target doses of rate controlling drugs.

  7. Treatment initiation, program attrition and patient treatment outcomes associated with scale-up and decentralization of HIV care in rural Malawi.

    Science.gov (United States)

    McGuire, Megan; Pinoges, Loretxu; Kanapathipillai, Rupa; Munyenyembe, Tamika; Huckabee, Martha; Makombe, Simon; Szumilin, Elisabeth; Heinzelmann, Annette; Pujades-Rodríguez, Mar

    2012-01-01

    To describe patient antiretroviral therapy (cART) outcomes associated with intensive decentralization of services in a rural HIV program in Malawi. Longitudinal analysis of data from HIV-infected patients starting cART between August 2001 and December 2008 and of a cross-sectional immunovirological assessment conducted 12 (±2) months after therapy start. One-year mortality, lost to follow-up, and attrition (deaths and lost to follow-up) rates were estimated with exact Poisson 95% confidence intervals (CI) by type of care delivery and year of initiation. Association of virological suppression (centralized care and 11,090 decentralized care. At therapy start, patients treated in decentralized health facilities had higher median CD4 count levels (167 vs. 130 cell/µL, Pdecentralized than centralized facilities (9.9 per 100 person-years, 95% CI: 9.5-10.4 vs. 20.8 per 100 person-years, 95% CI: 19.7-22.0). One year after treatment start, differences in immunological success (adjusted OR=1.23, 95% CI: 0.83-1.83), and viral suppression (adjusted OR=0.80, 95% CI: 0.56-1.14) between patients followed at centralized and decentralized facilities were not statistically significant. In rural Malawi, 1- and 2-year program attrition was lower in decentralized than in centralized health facilities and no statistically significant differences in one-year immunovirological outcomes were observed between the two health care levels. Longer follow-up is needed to confirm these results.

  8. Inferences About the Distribution, Merger Rate, and Evolutionary Processes of Compact Binaries From Gravitational Wave Observations

    Science.gov (United States)

    Wysocki, Daniel

    We are living through the dawn of the era of gravitational wave astronomy. Our first glances through this new window upon the sky has revealed a new population of objects. Since it first began observing in late 2015, the advanced Laser Interferometer Gravitational-Wave Observatory (LIGO) has detected gravitational waves three times, along with an additional strong candidate - and there shall be orders of magnitude more in the years to come. In all four cases, the waveform's signature is consistent with general relativity's predictions for the merging of two black holes. Through parameter estimation studies, estimates on features such as the black holes' masses and spins have been determined. At least two of the black hole pairs lie above the mass range spanned by comparable black holes observed through traditional means. This suggests they constitute a separate population, either too elusive or rare to be found with traditional telescopes. The most natural questions to ask about these black holes - how did they form, how many of them are there, and how can they be categorized - remain open ended. We know black holes can form when massive stars die, so it's most natural to claim stars as their progenitors. Since we now know black holes merge into larger black holes, could it be the case that they formed from previous mergers? Were the two black holes part of a binary from their birth, or did they become coupled later on in life? The measurements provided by LIGO can help answer these questions and more. Throughout this thesis, I will describe and demonstrate results from a number of novel methods whose purpose is to better understand these black holes and their progenitors. At their heart, these methods give answers to a few, critical questions. a) What is the overall rate at which these objects merge? b) What is the range of values these objects' properties can take, and how are they distributed? c) Given a number of physical models, how can we evaluate the

  9. Evaluation of oestrus observation and conception rates in suckling beef cows using whole milk progesterone concentration

    Directory of Open Access Journals (Sweden)

    D.C. Lourens

    2002-07-01

    Full Text Available A 2-sample regime was used to measure whole milk progesterone concentration on the day of oestrus and insemination (Day 0 and 6 days later (Day 6 in a sample of 50 primiparous and 100 multiparous suckling beef cows. Exposure to teaser bulls and observation by cattlemen identified the occurrence of oestrus. Three sets of criteria used to define ovulatory oestrus were compared : a milk progesterone concentration less than 6 nmol / l on Day 0 ; b milk progesterone less than 6 nmol / l on Day 0 and rising to greater than 6 nmol / l on Day 6; c milk progesterone less than 6 nmol / l on Day 0 and rising to greater than 6 nmol / l on Day 6, or cow diagnosed pregnant to 1st insemination. Using only a single milk sample on Day 0 (criterion a would have resulted in the positive predictive value of heat detection being estimated at 98.7%. Using a paired measurement (criterion b resulted in a significantly lower estimate of 84.7%. The inclusion of cows that conceived despite not showing a marked rise in milk progesterone concentration (criterion c resulted in a more accurate estimate of 89.3%. Use of a 2-sample regime also allowed calculation of conception rates while eliminating the effect of heat detection errors. In the cows sampled, of those in ovulatory oestrus that were inseminated, 73.1% conceived to the 1st insemination. These results demonstrate that artificial insemination within a limited breeding season can be successful if nutrition is optimal and management is intensive. The use of a 2-sample milk progesterone test may be a valuable tool in investigating heat detection and conception problems in beef herds in which artificial insemination is used.

  10. Observer-rated coping associated with borderline personality disorder: an exploratory study.

    Science.gov (United States)

    Kramer, Ueli

    2014-01-01

    Little is known about coping specificities, as operationalization of the concept of affect regulation, in borderline personality disorder (BPD). It is most important to take into account methodological criticisms addressed to the self-report questionnaire approach and to compare BPD coping specificities to the ones of neighbouring diagnostic categories, such as bipolar disorder (BD). The present exploratory study compared the coping profiles of N = 25 patients presenting BPD to those of N = 25 patients presenting BD and to those of N = 25 healthy controls. All participants underwent a clinical interview that was transcribed and rated using the Coping Patterns observer-rater system. Results partially confirmed study hypotheses and showed differences between BPD patients and healthy controls in all coping domains (competence, resources and autonomy), whereas the only coping domain presenting a BPD-specific lack of skills, compared with the BD patients, was autonomy, a set of coping strategies facing stress appraised as challenge. These coping processes were linked to general and BPD symptomatology. These results extend conclusions of earlier studies on affect regulation processes in BPD and bear important clinical implications, in the context of dialectical behavior therapy and other therapeutic approaches. Limitations of this exploratory study, such as the small sample size, are acknowledged. Coping can be reliably assessed in the narrative process in an non-structured interview frame. Patients with borderline personality disorder present with a specific lack of skills in affect regulation related to autonomy issues, compared to patients with bipolar disorder and healthy controls. Lack of skills in accommodation to distressing emotions in borderline personality disorder is related to symptom gravity and may be treated using radical acceptance strategies. Copyright © 2012 John Wiley & Sons, Ltd.

  11. Developing a national computerised absence monitoring and management system to reduce nursing student attrition: evaluation of staff and student perspectives.

    Science.gov (United States)

    Currie, Kay; McCallum, Jacqueline; Murray, John; Scott, Janine; Strachan, Evelyn; Yates, Lynda; Wright, Marty

    2014-05-01

    avoid student frustration. Further research on the longer term impact of CAMMS on attrition rates is warranted. © 2013.

  12. Inconsistencies in patient perceptions and observer ratings of shared decision making: the case of colorectal cancer screening.

    Science.gov (United States)

    Wunderlich, Tracy; Cooper, Gregory; Divine, George; Flocke, Susan; Oja-Tebbe, Nancy; Stange, Kurt; Lafata, Jennifer Elston

    2010-09-01

    To compare patient-reported and observer-rated shared decision making (SDM) use for colorectal cancer (CRC) screening and evaluate patient, physician and patient-reported relational communication factors associated with patient-reported use of shared CRC screening decisions. Study physicians are salaried primary care providers. Patients are insured, aged 50-80 and due for CRC screening. Audio-recordings from 363 primary care visits were observer-coded for elements of SDM. A post-visit patient survey assessed patient-reported decision-making processes and relational communication during visit. Association of patient-reported SDM with observer-rated elements of SDM, as well as patient, physician and relational communication factors were evaluated using generalized estimating equations. 70% of patients preferred SDM for preventive health decisions, 47% of patients reported use of a SDM process, and only one of the screening discussions included all four elements of SDM per observer ratings. Patient report of SDM use was not associated with observer-rated elements of SDM, but was significantly associated with female physician gender and patient-reported relational communication. Inconsistencies exist between patient reports and observer ratings of SDM for CRC screening. Future studies are needed to understand whether SDM that is patient-reported, observer-rated or both are associated with informed and value-concordant CRC screening decisions. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.

  13. Attrition and Rape Case Characteristics: A Profile and Comparison of Female Sex Workers and Non-Sex Workers.

    Science.gov (United States)

    Lea, Susan J; Callaghan, Lynne; Grafton, Iain; Falcone, M Aurora; Shaw, Steve

    2016-07-01

    The attrition of rape cases from the criminal justice system (CJS) remains high and there is a paucity of research in relation to marginalized groups. Sex workers (SWs) are vulnerable to sexual violence due to the nature of their work. They are also unlikely to report such violence to police for a range of reasons. Two stages of research sought to describe the victim, perpetrator, and offense characteristics of SW rape and to examine the attrition of these cases. All rapes and attempted rapes (N = 1,146) reported to police in a large city in the South West of England over a 21-year period were examined; 67 cases involved SWs. Data were extracted from police files in line with the variables of interest. Secondary analysis of the total number of SW rapes (n = 67) resulted in a profile of these cases. A matched pairs study revealed significant differences in victim, perpetrator, and assault characteristics between SW (n = 62) and non-sex-worker (NSW) samples (n = 62). Although no significant difference was found in terms of attrition from the CJS, SW cases were observed to secure more convictions for rape than NSW cases. The implications of the findings for practice and future research are discussed. © The Author(s) 2015.

  14. Investigation of the behaviour of both dead time and observed counting rates of He-3 gas filled neutron detector

    Energy Technology Data Exchange (ETDEWEB)

    Adib, M.; Eid, Y.; Abdel Kawy, A.; Maayouf, R.M.A.; Shuriet, G.M.; Hamouda, I.

    1981-01-01

    The behaviour of the dead time of He-3 detector, operating at both the proportional and the corona discharge regions, is investigated as a function of the neutron reaction rate inside the detector. The applied experimental method makes use of the fluctuations, due to the detector dead time in the observed counting rates from Poisson's distribution. In order to check the validity of the experimental method used in the present work, the dead time of BF/sub 3/ neutron detectors with different efficiencies (due to different enrichement in B-10) were determined. It is shown that the observed counting rate from the He-3 detector operating at the proportional region for neutron reaction rates ranging from 8 x 10/sup 3/ to 2.5 x 10/sup 4/ reaction/sec decreases with the increase of the neutron reaction rate. Such behaviour was not observed when operating the He-3 detector at the corona discharge region.

  15. Investigation of the behaviour of both dead time and observed counting rates of He-3 gas filled neutron detector

    International Nuclear Information System (INIS)

    Adib, M.; Eid, Y.; Abdel Kawy, A.; Maayouf, R.M.A.; Shuriet, G.M.; Hamouda, I.

    1981-01-01

    The behaviour of the dead time of He-3 detector, operating at both the proportional and the corona discharge regions, is investigated as a function of the neutron reaction rate inside the detector. The applied experimental method makes use of the fluctuations, due to the detector dead time in the observed counting rates from Poisson's distribution. In order to check the validity of the experimental method used in the present work, the dead time of BF 3 neutron detectors with different efficiencies (due to different enrichement in B-10) were determined. It is shown that the observed counting rate from the He-3 detector operating at the proportional region for neutron reaction rates ranging from 8 x 10 3 to 2.5 x 10 4 reaction/sec decreases with the increase of the neutron reaction rate. Such behaviour was not observed when operating the He-3 detector at the corona discharge region. (orig.) [de

  16. New England observed and predicted August stream/river temperature maximum positive daily rate of change points

    Data.gov (United States)

    U.S. Environmental Protection Agency — The shapefile contains points with associated observed and predicted August stream/river temperature maximum positive daily rate of change in New England based on a...

  17. New England observed and predicted July stream/river temperature maximum positive daily rate of change points

    Data.gov (United States)

    U.S. Environmental Protection Agency — The shapefile contains points with associated observed and predicted July stream/river temperature maximum positive daily rate of change in New England based on a...

  18. New England observed and predicted July maximum negative stream/river temperature daily rate of change points

    Data.gov (United States)

    U.S. Environmental Protection Agency — The shapefile contains points with associated observed and predicted July stream/river temperature maximum negative daily rate of change in New England based on a...

  19. The Secant Rate of Corrosion: Correlating Observations of the USS Arizona Submerged in Pearl Harbor

    Science.gov (United States)

    Johnson, Donald L.; DeAngelis, Robert J.; Medlin, Dana J.; Johnson, Jon E.; Carr, James D.; Conlin, David L.

    2018-03-01

    Contrary to previous linear projections of steel corrosion in seawater, analysis of an inert marker embedded in USS Arizona concretion since the 7 December 1941 attack on Pearl Harbor reveals evidence that the effective corrosion rate decreases with time. The secant rate of corrosion, or SRC correlation, derived from this discovery could have a significant impact on failure analysis investigations for concreted shipwrecks or underwater structures. The correlation yields a lower rate of metal thinning than predicted. Development of the correlation is described.

  20. Corrosion rate transients observed by linear polarization techniques at Zr-1%Nb alloy

    International Nuclear Information System (INIS)

    Beran, J.; Cerny, K.

    1997-01-01

    Momentary corrosion rate of Zr-1%Nb alloy during nonisothermal autoclave experiments at temperature up to 328 deg. C in various solutions was determined by T/R p values (T - absolute temperature, R p - polarization resistance), multiplied by temperature independent conversion factor. This factor was found by comparison of conventional corrosion loss evaluation with electrochemical measurements. Corrosion rate transients in boric acid solutions and in lithium hydroxide differed significantly. Great differences were also found in stabilized corrosion rates at the end of experiments. Temperature irregularities caused considerable changes in corrosion rate. (author). 5 refs, 5 figs, 1 tab

  1. Corrosion rate transients observed by linear polarization techniques at Zr-1%Nb alloy

    Energy Technology Data Exchange (ETDEWEB)

    Beran, J; Cerny, K [ZJS SKODA plc., Pelzen (Czech Republic)

    1997-02-01

    Momentary corrosion rate of Zr-1%Nb alloy during nonisothermal autoclave experiments at temperature up to 328 deg. C in various solutions was determined by T/R{sub p} values (T - absolute temperature, R{sub p}- polarization resistance), multiplied by temperature independent conversion factor. This factor was found by comparison of conventional corrosion loss evaluation with electrochemical measurements. Corrosion rate transients in boric acid solutions and in lithium hydroxide differed significantly. Great differences were also found in stabilized corrosion rates at the end of experiments. Temperature irregularities caused considerable changes in corrosion rate. (author). 5 refs, 5 figs, 1 tab.

  2. The nature and causes of attrition in the British Household Panel Study

    OpenAIRE

    Uhrig, S.C. Noah

    2008-01-01

    Panel attrition is a process producing data absent from panel records due to survey non-participation or other data unavailability. I examine the nature and causes of attrition resulting from non-contact and survey refusal in the British Household Panel Study. Focusing on non-response transitions amongst Wave 1 respondents using discrete time transition models, I locate attrition at first non-response over the first 14 waves. Physical impediments to contact, less time spent at home and high l...

  3. An Analysis of Recruit Training Attrition in the U.S. Marine Corps

    Science.gov (United States)

    1978-02-01

    Administration NR 170-819 I I. CONTROLLING OFFICE NAME AND ADDRESS It. ROILPORT CATS Organizational Effectiveness Research Programs February 1978 / Office of...for over 60% of the administrativo reasons for attrition. This finding underscores the importance of behavioral approaches to understanding and... controlled attrition may serve to confound individual level analyses of attrition. Although the R2 in this study is .10, this is not trivial. This

  4. Modulations of Heart Rate, ECG, and Cardio-Respiratory Coupling Observed in Polysomnography

    Directory of Open Access Journals (Sweden)

    Thomas Penzel

    2016-10-01

    Full Text Available The cardiac component of cardio-respiratory polysomnography is covered by ECG and heart rate recordings. However their evaluation is often underrepresented in summarizing reports. As complements to EEG, EOG, and EMG, these signals provide diagnostic information for autonomic nervous activity during sleep. This review presents major methodological developments in sleep research regarding heart rate, ECG and cardio-respiratory couplings in a chronological (historical sequence. It presents physiological and pathophysiological insights related to sleep medicine obtained by new technical developments. Recorded nocturnal ECG facilitates conventional heart rate variability analysis, studies of cyclical variations of heart rate, and analysis of ECG waveform. In healthy adults, the autonomous nervous system is regulated in totally different ways during wakefulness, slow-wave sleep, and REM sleep. Analysis of beat-to-beat heart-rate variations with statistical methods enables us to estimate sleep stages based on the differences in autonomic nervous system regulation. Furthermore, up to some degree, it is possible to track transitions from wakefulness to sleep by analysis of heart-rate variations. ECG and heart rate analysis allow assessment of selected sleep disorders as well. Sleep disordered breathing can be detected reliably by studying cyclical variation of heart rate combined with respiration-modulated changes in ECG morphology (amplitude of R wave and T wave.

  5. Modulations of Heart Rate, ECG, and Cardio-Respiratory Coupling Observed in Polysomnography.

    Science.gov (United States)

    Penzel, Thomas; Kantelhardt, Jan W; Bartsch, Ronny P; Riedl, Maik; Kraemer, Jan F; Wessel, Niels; Garcia, Carmen; Glos, Martin; Fietze, Ingo; Schöbel, Christoph

    2016-01-01

    The cardiac component of cardio-respiratory polysomnography is covered by ECG and heart rate recordings. However, their evaluation is often underrepresented in summarizing reports. As complements to EEG, EOG, and EMG, these signals provide diagnostic information for autonomic nervous activity during sleep. This review presents major methodological developments in sleep research regarding heart rate, ECG, and cardio-respiratory couplings in a chronological (historical) sequence. It presents physiological and pathophysiological insights related to sleep medicine obtained by new technical developments. Recorded nocturnal ECG facilitates conventional heart rate variability (HRV) analysis, studies of cyclical variations of heart rate, and analysis of ECG waveform. In healthy adults, the autonomous nervous system is regulated in totally different ways during wakefulness, slow-wave sleep, and REM sleep. Analysis of beat-to-beat heart-rate variations with statistical methods enables us to estimate sleep stages based on the differences in autonomic nervous system regulation. Furthermore, up to some degree, it is possible to track transitions from wakefulness to sleep by analysis of heart-rate variations. ECG and heart rate analysis allow assessment of selected sleep disorders as well. Sleep disordered breathing can be detected reliably by studying cyclical variation of heart rate combined with respiration-modulated changes in ECG morphology (amplitude of R wave and T wave).

  6. High maternal and neonatal mortality rates in northern Nigeria: an 8-month observational study

    Directory of Open Access Journals (Sweden)

    Guerrier G

    2013-08-01

    Full Text Available Gilles Guerrier,1 Bukola Oluyide,2 Maria Keramarou,1 Rebecca Grais1 1Epicentre, Paris, France; 2Médecins Sans Frontières, Paris, France Background: Despite considerable efforts to reduce the maternal mortality ratio, numerous pregnant women continue to die in many developing countries, including Nigeria. We conducted a study to determine the incidence and causes of maternal mortality over an 8-month period in a rural-based secondary health facility located in Jahun, northern Nigeria. Methods: A retrospective observational study was performed in a 41-bed obstetric ward. From October 2010 to May 2011, demographic data, obstetric characteristics, and outcome were collected from all pregnant women admitted. The total number of live births during the study period was recorded in order to calculate the maternal mortality ratio. Results: There were 2,177 deliveries and 39 maternal deaths during the study period, with a maternal mortality ratio of 1,791/100,000 live births. The most common causes of maternal mortality were hemorrhage (26%, puerperal sepsis (19%, and obstructed labor (5%. No significant difference (P = 0.07 in mean time to reach the hospital was noted between fatal cases (1.9 hours, 95% confidence interval [CI] 1.1–2.6 and nonfatal cases (1.4 hours, 95% CI 1.4–1.5. Two hundred and sixty-six women were admitted presenting with stillbirth. Maternal mortality was higher for unbooked patients than for booked patients (odds ratio 5.1, 95% CI 3.5–6.2, P < 0.0001. The neonatal mortality rate was calculated at 46/1,000 live births. The main primary causes of neonatal deaths were prematurity (44% and birth asphyxia (22%. Conclusion: Maternal and neonatal mortality remains unacceptably high in this setting. Reducing unbooked emergencies should be a priority with continuous programs including orthodox practices in order to meet the fifth Millennium Development Goal. Keywords: fetal mortality, maternal mortality, Nigeria, antenatal care

  7. Initial Entry Training: Reducing First Term Attrition Through Effective Organizational Socialization

    National Research Council Canada - National Science Library

    Hayden, Thomas

    2000-01-01

    .... Behavioral scientist claim that attrition in organizations can be attributed to many factors such as lack of commitment to the organization, poor skill development, mismatch in employee expectations...

  8. Reevaluation of the O+(2P) reaction rate coefficients derived from atmosphere explorer C observations

    International Nuclear Information System (INIS)

    Chang, T.; Torr, D.G.; Richards, P.G.; Solomon, S.C.

    1993-01-01

    O + ( 2 P) is an important species for studies of the ionosphere and thermosphere: its emission at 7320 angstrom can be used as a diagnostic of the thermospheric atomic oxygen density. Unfortunately, there are no laboratory measurements of the O and N 2 reaction rates which are needed to determine the major sinks of O + ( 2 P). The reaction rates that are generally used were determined from aeronomic data by Rusch et al. but there is evidence that several important inputs that they used should be changed. The authors have recalculated the O and N 2 reaction rates for O + ( 2 P) using recent improvements in the solar EUV flux, cross sections, and photoelectron fluxes. For the standard solar EUV flux, the new N 2 reaction rate of 3.4 ± 1.5 x 10 -10 cm 3 s -1 is close to the value obtained by Rusch et al., but the new O reaction rate of 4.0 ± 1.9 x 10 -10 cm 3 s -1 is about 8 times larger. These new reaction rates are derived using neutral densities, electron density, and solar EUV fluxes measured by Atmosphere Explorer C in 1974 during solar minimum. The new theoretical emission rates are in good agreement with the data for the two orbits studied by Rusch et al. and they are in reasonable agreement with data from five additional orbits that are used in this study. The authors have also examined the effect of uncertainties in the solar EUV flux on the derived reaction rates and found that 15% uncertainties in the solar flux could cause additional uncertainties of up to a factor of 1.5 in the O quenching rate. 19 refs., 4 figs., 8 tabs

  9. Gait in children with cerebral palsy : observer reliability of Physician Rating Scale and Edinburgh Visual Gait Analysis Interval Testing scale

    NARCIS (Netherlands)

    Maathuis, KGB; van der Schans, CP; van Iperen, A; Rietman, HS; Geertzen, JHB

    2005-01-01

    The aim of this study was to test the inter- and intra-observer reliability of the Physician Rating Scale (PRS) and the Edinburgh Visual Gait Analysis Interval Testing (GAIT) scale for use in children with cerebral palsy (CP). Both assessment scales are quantitative observational scales, evaluating

  10. Controls on surface soil drying rates observed by SMAP and simulated by the Noah land surface model

    Science.gov (United States)

    Shellito, Peter J.; Small, Eric E.; Livneh, Ben

    2018-03-01

    Drydown periods that follow precipitation events provide an opportunity to assess controls on soil evaporation on a continental scale. We use SMAP (Soil Moisture Active Passive) observations and Noah simulations from drydown periods to quantify the role of soil moisture, potential evaporation, vegetation cover, and soil texture on soil drying rates. Rates are determined using finite differences over intervals of 1 to 3 days. In the Noah model, the drying rates are a good approximation of direct soil evaporation rates, and our work suggests that SMAP-observed drying is also predominantly affected by direct soil evaporation. Data cover the domain of the North American Land Data Assimilation System Phase 2 and span the first 1.8 years of SMAP's operation. Drying of surface soil moisture observed by SMAP is faster than that simulated by Noah. SMAP drying is fastest when surface soil moisture levels are high, potential evaporation is high, and when vegetation cover is low. Soil texture plays a minor role in SMAP drying rates. Noah simulations show similar responses to soil moisture and potential evaporation, but vegetation has a minimal effect and soil texture has a much larger effect compared to SMAP. When drying rates are normalized by potential evaporation, SMAP observations and Noah simulations both show that increases in vegetation cover lead to decreases in evaporative efficiency from the surface soil. However, the magnitude of this effect simulated by Noah is much weaker than that determined from SMAP observations.

  11. Do Case Rates Affect Physicians' Clinical Practice in Radiation Oncology?: An Observational Study.

    Directory of Open Access Journals (Sweden)

    Bryan A Loy

    Full Text Available Case rate payments combined with utilization monitoring may have the potential to improve the quality of care by reducing over and under-treatment. Thus, a national managed care organization introduced case rate payments at one multi-site radiation oncology provider while maintaining only fee-for-service payments at others. This study examined whether the introduction of the payment method had an effect on radiation fractions administered when compared to clinical guidelines. The number of fractions of radiation therapy delivered to patients with bone metastases, breast, lung, prostate, and skin cancer was assessed for concordance with clinical guidelines. The proportion of guideline-based care ascertained from the payer's claims database was compared before (2011 and after (2013 the payment method introduction using relative risks (RR. After the introduction of case rates, there were no significant changes in guideline-based care in breast, lung, and skin cancer; however, patients with bone metastases and prostate cancer were significantly more likely to have received guideline-based care (RR = 2.0 and 1.1, respectively, p<0.05. For the aggregate of all cancers, the under-treatment rate significantly declined (p = 0.008 from 4% to 0% after the introduction of case rate payments, while the over-treatment rate remained steady at 9%, with no significant change (p = 0.20. These findings suggest that the introduction of case rate payments did not adversely affect the rate of guideline-based care at the provider examined. Additional research is needed to isolate the effect of the payment model and assess implications in other populations.

  12. Do Case Rates Affect Physicians' Clinical Practice in Radiation Oncology?: An Observational Study.

    Science.gov (United States)

    Loy, Bryan A; Shkedy, Clive I; Powell, Adam C; Happe, Laura E; Royalty, Julie A; Miao, Michael T; Smith, Gary L; Long, James W; Gupta, Amit K

    2016-01-01

    Case rate payments combined with utilization monitoring may have the potential to improve the quality of care by reducing over and under-treatment. Thus, a national managed care organization introduced case rate payments at one multi-site radiation oncology provider while maintaining only fee-for-service payments at others. This study examined whether the introduction of the payment method had an effect on radiation fractions administered when compared to clinical guidelines. The number of fractions of radiation therapy delivered to patients with bone metastases, breast, lung, prostate, and skin cancer was assessed for concordance with clinical guidelines. The proportion of guideline-based care ascertained from the payer's claims database was compared before (2011) and after (2013) the payment method introduction using relative risks (RR). After the introduction of case rates, there were no significant changes in guideline-based care in breast, lung, and skin cancer; however, patients with bone metastases and prostate cancer were significantly more likely to have received guideline-based care (RR = 2.0 and 1.1, respectively, p<0.05). For the aggregate of all cancers, the under-treatment rate significantly declined (p = 0.008) from 4% to 0% after the introduction of case rate payments, while the over-treatment rate remained steady at 9%, with no significant change (p = 0.20). These findings suggest that the introduction of case rate payments did not adversely affect the rate of guideline-based care at the provider examined. Additional research is needed to isolate the effect of the payment model and assess implications in other populations.

  13. Binary and multi-category ratings in a laboratory observer performance study: A comparison

    OpenAIRE

    Gur, David; Bandos, Andriy I.; King, Jill L.; Klym, Amy H.; Cohen, Cathy S.; Hakim, Christiane M.; Hardesty, Lara A.; Ganott, Marie A.; Perrin, Ronald L.; Poller, William R.; Shah, Ratan; Sumkin, Jules H.; Wallace, Luisa P.; Rockette, Howard E.

    2008-01-01

    The authors investigated radiologists, performances during retrospective interpretation of screening mammograms when using a binary decision whether to recall a woman for additional procedures or not and compared it with their receiver operating characteristic (ROC) type performance curves using a semi-continuous rating scale. Under an Institutional Review Board approved protocol nine experienced radiologists independently rated an enriched set of 155 examinations that they had not personally...

  14. Reevaluation of the O(+)(2P) reaction rate coefficients derived from Atmosphere Explorer C observations

    Science.gov (United States)

    Chang, T.; Torr, D. G.; Richards, P. G.; Solomon, S. C.

    1993-01-01

    O(+)(2P) is an important species for studies of the ionosphere and thermosphere: its emission at 7320 A can be used as a diagnostic of the thermospheric atomic oxygen density. Unfortunately, there are no laboratory measurements of the O and N2 reaction rates which are needed to determine the major sinks of (O+)(2p). We have recalculated the O and N2 reaction rates for O(+) (2P) using recent improvements in the solar EUV flux, cross sections, and photoelectron fluxes. For the standard solar EUV flux, the new N2 reaction rate of 3.4 +/- 1.5 x 10 exp -10 cu cm/s is close to the value obtained by Rusch et al. (1977), but the new O reaction rate of 4.0 +/- 1.9 x 10 exp -10 cu cm/sec is about 8 times larger. These new reaction rates are derived using neutral densities, electron density, and solar EUV fluxes measured by Atmosphere Explorer C in 1974 during solar minimum. The new theoretical emission rates are in good agreement with the data for the two orbits studied by Rusch et al.

  15. Attrition of limestone by impact loading in fluidized beds

    Energy Technology Data Exchange (ETDEWEB)

    Fabrizio Scala; Fabio Montagnaro; Piero Salatino [Consiglio Nazionale delle Ricerche, Napoli (Italy). Istituto di Ricerche sulla Combustione

    2007-09-15

    The present study addresses limestone attrition and fragmentation associated with impact loading, a process which may occur extensively in various regions of fluidized bed (FB) combustors/gasifiers, primarily the jetting region of the bottom bed, the exit region of the riser, and the cyclone. An experimental protocol for the characterization of the propensity of limestone to undergo attrition/fragmentation by impact loading is reported. The application of the protocol is demonstrated with reference to an Italian limestone whose primary fragmentation and attrition by surface wear have already been characterized in previous studies. The experimental procedure is based on the characterization of the amount and particle size distribution of the debris generated upon the impact of samples of sorbent particles against a target. Experiments were carried out at a range of particle impact velocities between 10 and 45 m/s, consistent with jet velocities corresponding to typical pressure drops across FB gas distributors. The protocol has been applied to either raw or preprocessed limestone samples. In particular, the effect of calcination, sulfation, and calcination/recarbonation cycles on the impact damage suffered by sorbent particles has been assessed. The measurement of particle voidage and pore size distribution by mercury intrusion was also accomplished to correlate fragmentation with the structural properties of the sorbent samples. Fragmentation by impact loading of the limestone is significant. Lime displays the largest propensity to undergo impact damage, followed by the sorbent sulfated to exhaustion, the recarbonated sorbent, and the raw limestone. Fragmentation of the raw limestone and of the sulfated lime follows a pattern typical of the failure of brittle materials. The fragmentation behavior of lime and recarbonated lime better conforms to a disintegration failure mode, with an extensive generation of very fine fragments. 27 refs., 9 figs. 1 tab.

  16. Early nurse attrition in New Zealand and associated policy implications.

    Science.gov (United States)

    Walker, L; Clendon, J

    2018-03-01

    To examine the factors contributing to nurses choosing to exit the nursing profession before retirement age. Population growth, ageing and growing demand for health services mean increased demand for nurses. Better retention could help meet this demand, yet little work has been done in New Zealand to understand early attrition. An online survey of registered and enrolled nurses and nurse practitioners who had left nursing was used. This study reports analysis of responses from 285 ex-nurses aged under 55. The primary reasons nurses left the profession were as follows: workplace concerns; personal challenges; career factors; family reasons; lack of confidence; leaving for overseas; unwillingness to complete educational requirements; poor work-life balance; and inability to find suitable nursing work. Most nurses discussed their intentions to leave with a family member or manager and most reported gaining transferrable skills through nursing. Nurses leave for many reasons. Implementing positive practice environments and individualized approaches to retaining staff may help reduce this attrition. Generational changes in the nature of work and careers mean that nurses may continue to leave the profession sooner than anticipated by policymakers. If the nursing workforce is to be able to meet projected need, education, recruitment and retention policies must urgently address issues leading to early attrition. In particular, policies improving the wider environmental context of nursing practice and ensuring that working environments are safe and nurses are well supported must be developed and implemented. Equally, national nursing workforce planning must take into account that nursing is no longer viewed as a career for life. © 2017 International Council of Nurses.

  17. Coloring Rate of Phenolphthalein by Reaction with Alkaline Solution Observed by Liquid-Droplet Collision.

    Science.gov (United States)

    Takano, Yuuka; Kikkawa, Shigenori; Suzuki, Tomoko; Kohno, Jun-ya

    2015-06-11

    Many important chemical reactions are induced by mixing two solutions. This paper presents a new way to measure rates of rapid chemical reactions induced by mixing two reactant solutions using a liquid-droplet collision. The coloring reaction of phenolphthalein (H2PP) by a reaction with NaOH is investigated kinetically. Liquid droplets of H2PP/ethanol and NaOH/H2O solutions are made to collide, which induces a reaction that transforms H2PP into a deprotonated form (PP(2-)). The concentration of PP(2-) is evaluated from the RGB values of pixels in the colored droplet images, and is measured as a function of the elapsed time from the collision. The obtained rate constant is (2.2 ± 0.7) × 10(3) M(-1) s(-1), which is the rate constant for the rate-determining step of the coloring reaction of H2PP. This method was shown to be applicable to determine rate constants of rapid chemical reactions between two solutions.

  18. Hydrostatic Pressurization of Lung Surfactant Microbubbles: Observation of a Strain-Rate Dependent Elasticity.

    Science.gov (United States)

    Thomas, Alec N; Borden, Mark A

    2017-11-28

    The microbubble offers a unique platform to study lung surfactant mechanics at physiologically relevant geometry and length scale. In this study, we compared the response of microbubbles (∼15 μm initial radius) coated with pure dipalmitoyl-phosphatidylcholine (DPPC) versus naturally derived lung surfactant (SURVANTA) when subjected to linearly increasing hydrostatic pressure at different rates (0.5-2.3 kPa/s) at room temperature. The microbubbles contained perfluorobutane gas and were submerged in buffered saline saturated with perfluorobutane at atmospheric pressure. Bright-field microscopy showed that DPPC microbubbles compressed spherically and smoothly, whereas SURVANTA microbubbles exhibited wrinkling and smoothing cycles associated with buckling and collapse. Seismograph analysis showed that the SURVANTA collapse amplitude was constant, but the collapse rate increased with the pressurization rate. An analysis of the pressure-volume curves indicated that the dilatational elasticity increased during compression for both shell types. The initial dilatational elasticity for SURVANTA was nearly twice that of DPPC at higher pressurization rates (>1.5 kPa/s), producing a pressure drop of up to 60 kPa across the film prior to condensation of the perfluorobutane core. The strain-rate dependent stiffening of SURVANTA shells likely arises from their composition and microstructure, which provide enhanced in-plane monolayer rigidity and lateral repulsion from surface-associated collapse structures. Overall, these results provide new insights into lung surfactant mechanics and collapse behavior during compression.

  19. Field observations of turbulent dissipation rate profiles immediately below the air-water interface

    Science.gov (United States)

    Wang, Binbin; Liao, Qian

    2016-06-01

    Near surface profiles of turbulence immediately below the air-water interface were measured with a free-floating Particle Image Velocimetry (PIV) system on Lake Michigan. The surface-following configuration allowed the system to measure the statistics of the aqueous-side turbulence in the topmost layer immediately below the water surface (z≈0˜15 cm, z points downward with 0 at the interface). Profiles of turbulent dissipation rate (ɛ) were investigated under a variety of wind and wave conditions. Various methods were applied to estimate the dissipation rate. Results suggest that these methods yield consistent dissipation rate profiles with reasonable scattering. In general, the dissipation rate decreases from the water surface following a power law relation in the top layer, ɛ˜z-0.7, i.e., the slope of the decrease was lower than that predicted by the wall turbulence theory, and the dissipation was considerably higher in the top layer for cases with higher wave ages. The measured dissipation rate profiles collapse when they were normalized with the wave speed, wave height, water-side friction velocity, and the wave age. This scaling suggests that the enhanced turbulence may be attributed to the additional source of turbulent kinetic energy (TKE) at the "skin layer" (likely due to micro-breaking), and its downward transport in the water column.

  20. Can Mindful Parenting Be Observed? Relations between Observational Ratings of Mother-Youth Interactions and Mothers’ Self-Report Mindful Parenting

    Science.gov (United States)

    Duncan, Larissa G.; Coatsworth, J. Douglas; Gayles, Jochebed G.; Geier, Mary H.; Greenberg, Mark T.

    2015-01-01

    Research on mindful parenting, an extension of mindfulness to the interpersonal domain of parent-child relationships, has been limited by its reliance on self-report assessment. The current study is the first to examine whether observational indices of parent-youth interactions differentiate between high and low levels of self-reported mindful parenting. The Iowa Family Interaction Rating Scales (IFIRS) were used to code interactions between mothers and their 7th grade youth. Mothers drawn from the top and bottom quartiles (n = 375) of a larger distribution of self-reported interpersonal mindfulness in parenting (N = 804) represented clearly defined high and low mindful parenting groups. Discriminant function analysis (DFA) was used to analyze how well six composite IFIRS observational rating variables (e.g., parental warmth, consistent discipline) discriminated between high and low self-reports of mindful parenting. DFA results were cross-validated, with statistically significant canonical correlations found for both subsamples (p parenting and the observational ratings was also provided through hierarchical regression analyses conducted with a continuous predictor of mindful parenting using the full sample. Thus, the present study provides preliminary evidence for a link between self-reported mindful parenting and observed interactions between parents and youth. PMID:25844494

  1. Application of a Duration Model in Programs for Prevention of University Attrition

    Directory of Open Access Journals (Sweden)

    Verónica Herrero

    2013-12-01

    Full Text Available Institutional practices related to the prevention of desertion of university students increasingly require validated instruments in order to anticipate such behavior. In this regard, different statistical models generated from information related to the students themselves, their homes, their academic performance, among other determinants have demonstrated to be of crucial value. This study aims to demonstrate the importance of a series of determinants explored in other studies. The main objective is to apply a dropout rate predictive model with at risk university students in order to generate early and progressively more effective results. The research demonstrates the usefulness of the duration models in a sample of classroom students and the capacity to anticipate behavior of permanence/attrition across time. This was done with risk estimates using the Cox model.

  2. When did they leave, and why? A retrospective case study of attrition on the Nottingham undergraduate medical course

    Directory of Open Access Journals (Sweden)

    Yates Janet

    2012-06-01

    Full Text Available Abstract Background As part of a wider study into students who experience difficulties, we examined the course files of those who had failed to graduate. This was an exploratory, descriptive study investigating how many students left after academic failure or non-academic problems, or simply changed their minds about reading medicine, and at what stage. The aim of the study was to increase our knowledge about the timings of, and reasons for, attrition. This understanding might help to reduce student loss in the future, by informing selection procedures and improving pastoral support at critical times. It might also assist in long-term workforce planning in the NHS. Methods Relevant data on admission and course progress were extracted manually from the archived files of students who had failed to graduate from five recent consecutive cohorts (entry in 2000–2004 inclusive, using a customised Access database. Discrete categories of information were supplemented with free text entries. Results 1188 students registered over the five-year entry period and 73 (6% failed to graduate. The highest rates of attrition (46/1188, 4% occurred during the first two years (largely preclinical studies, with 34 students leaving voluntarily, including 11 within the first semester, and 12 having their courses terminated for academic failure. Seventeen left at the end of the third year (Honours course plus early clinical practice and the remaining ten during the final two clinical years. The reasons for attrition were not always clear-cut and often involved a mixture of academic, personal, social and health factors, especially mental health problems. Conclusions The causes of attrition are complex. A small number of students with clear academic failure might require individual educational interventions for remediation. However, this could have substantial resource implications for the Faculty. Mental health problems predominate in late course attrition and may have

  3. Concordance between VDU-users' ratings of comfort and perceived exertion with experts' observations of workplace layout and working postures.

    Science.gov (United States)

    Lindegård, A; Karlberg, C; Wigaeus Tornqvist, E; Toomingas, A; Hagberg, M

    2005-05-01

    The aim of the present study was to evaluate the concordance (agreement) between VDU-users' ratings of comfort and ergonomists' observations of workplace layout, and the concordance between VDU-users' ratings of perceived exertion and ergonomists' observations of working postures during VDU-work. The study population consisted of 853 symptom free subjects. Data on perceived comfort in different dimensions and data regarding perceived exertion in different body locations were collected by means of a questionnaire. Data concerning workplace layout and working postures were collected with an observation protocol, by an ergonomist. Concordance between ratings of comfort and observations of workplace layout was reasonably good for the chair and the keyboard (0.60, 0.58) and good regarding the screen and the input device (0.72, 0.61). Concordance between ratings of perceived exertion and observations of working postures indicated good agreement (0.63-0.77) for all measured body locations (neck, shoulder, wrist and trunk). In conclusion ratings of comfort and perceived exertion could be used as cost-efficient and user-friendly methods for practitioners to identify high exposure to poor workplace layout and poor working postures.

  4. Rate Constant Change of Photo Reaction of Bacteriorhodopsin Observed in Trimeric Molecular System.

    Science.gov (United States)

    Tsujiuchi, Yutaka; Masumoto, Hiroshi; Goto, Takashi

    2016-04-01

    To elucidate the time evolution of photo reaction of bacteriorhodopsin in glycerol mixed purple membrane at around 196 K under irradiation by red light, a kinetic model was constructed. The change of absorption with irradiation at times of 560 nm and 412 nm was analyzed for the purpose of determining reaction rates of photo reaction of bacteriorhodopsin and its product M intermediate. In this study it is shown that reaction rates of conversion from bacteriorhodopsin to the M intermediate can be explained by a set of linear differential equations. This model analysis concludes that bacteriorhodopsin in which constitutes a trimer unit with other two bacteriorhodopsin molecules changes into M intermediates in the 1.73 of reaction rate, in the initial step, and according to the number of M intermediate in a trimer unit, from three to one, the reaction rate of bacteriorhodopsin into M intermediates smaller as 1.73, 0.80, 0.19 which caused by influence of inter-molecular interaction between bacteriorhodopsin.

  5. Occurrence rate of ion upflow and downflow observed by the Poker Flat Incoherent Scatter Radar (PFISR)

    Science.gov (United States)

    Zou, S.; Lu, J.; Varney, R. H.

    2017-12-01

    This study aims to investigate the occurrence rate of ion upflow and downflow events in the auroral ionosphere, using a full 3-year (2011-2013) dataset collected by the Poker Flat Incoherent Scatter Radar (PFISR) at 65.5° magnetic latitude. Ion upflow and downflow events are defined if there are three consecutive data points larger/smaller than 100/-100 m/s in the ion field-aligned velocity altitude profile. Their occurrence rates have been evaluated as a function of magnetic local time (MLT), season, geomagnetic activity, solar wind and interplanetary magnetic field (IMF). We found that the ion upflows are twice more likely to occur on the nightside than the dayside, and have slightly higher occurrence rate near Fall equinox. In contrast, the ion downflow events are more likely to occur in the afternoon sector but also during Fall equinox. In addition, the occurrence rate of ion upflows on the nightside increases when the aurora electrojet index (AE) and planetary K index (Kp) increase, while the downflows measured on the dayside clearly increase as the AE and Kp increase. In general, the occurrence rate of ion upflows increases with enhanced solar wind and IMF drivers. This correlation is particularly strong between the upflows on the nightside and the solar wind dynamic pressure and IMF Bz. The lack of correlation of upflows on the dayside with these parameters is due to the location of PFISR, which is usually equatorward of the dayside auroral zone and within the nightside auroral zone under disturbed conditions. The occurrence rate of downflow at all MLTs does not show strong dependence on the solar wind and IMF conditions. However, it occurs much more frequently on the dayside when the IMF By is strongly positive, i.e., >10 nT and the IMF Bz is strongly negative, i.e., < -10 nT. We suggest that the increased occurrence rate of downflows on the dayside is associated with dayside storm-enhanced density and the plume.

  6. Martensitic phase transformations in the nanostructured surface layers induced by mechanical attrition treatment

    International Nuclear Information System (INIS)

    Ni Zhichun; Wang Xiaowei; Wu Erdong; Liu Gang

    2005-01-01

    Conversion electron Moessbauer spectroscopy (CEMS) and x-ray diffraction (XRD) analysis have been used to investigate the relationship between characteristics of phase transformation and the treatment time in surface nanocrystallized 316L stainless steel induced by surface mechanical attrition treatment (SMAT). A similar trend of development of the martensitic phase upon the treatment time has been observed from both CEMS and XRD measurements. However, in the CEMS measurement, two types of martensite phase with different magnetic hyperfine fields are revealed. Based on a random distribution of the non-iron coordinating atoms, a three-element theoretical model is developed to illustrate the difference of two types of martensite phase. The calculated results indicate the segregation of the non-iron atoms associated with SMAT treatment

  7. The use of crowdsourcing for dietary self-monitoring: crowdsourced ratings of food pictures are comparable to ratings by trained observers.

    Science.gov (United States)

    Turner-McGrievy, Gabrielle M; Helander, Elina E; Kaipainen, Kirsikka; Perez-Macias, Jose Maria; Korhonen, Ilkka

    2015-04-01

    Crowdsourcing dietary ratings for food photographs, which uses the input of several users to provide feedback, has potential to assist with dietary self-monitoring. This study assessed how closely crowdsourced ratings of foods and beverages contained in 450 pictures from the Eatery mobile app as rated by peer users (fellow Eatery app users) (n = 5006 peers, mean 18.4 peer ratings/photo) using a simple 'healthiness' scale were related to the ratings of the same pictures by trained observers (raters). In addition, the foods and beverages present in each picture were categorized and the impact on the peer rating scale by food/beverage category was examined. Raters were trained to provide a 'healthiness' score using criteria from the 2010 US Dietary Guidelines. The average of all three raters' scores was highly correlated with the peer healthiness score for all photos (r = 0.88, pcrowdsourcing holds potential to provide basic feedback on overall diet quality to users utilizing a low burden approach. © The Author 2014. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. The network of corporate clients: customer attrition at commercial banks

    Science.gov (United States)

    Lublóy, Á.; Szenes, M.

    2008-12-01

    Commercial banks might profit from the adoption of methods widely used in network theory. A decision making process might become biased if one disregards network effects within the corporate client portfolio. This paper models the phenomenon of customer attrition by generating a weighted and directed network of corporate clients linked by financial transactions. During the numerical study of the agent-based toy model we demonstrate that multiple steady states may exist. The statistical properties of the distinct steady states show similarities. We show that most companies of the same community choose the same bank in the steady state. In contrast to the case for the steady state of the Barabási-Albert network, market shares in this model equalize by network size. When modeling customer attrition in the network of 3 × 105 corporate clients, none of the companies followed the behavior of the initial switcher in three quarters of the simulations. The number of switchers exceeded 20 in 1% of the cases. In the worst-case scenario a total of 688 companies chose a competitor bank. Significant network effects have been discovered; high correlation prevailed between the degree of the initial switcher and the severity of the avalanche effect. This suggests that the position of the corporate client in the network might be much more important than the underlying properties (industry, size, profitability, etc) of the company.

  9. From emigrant to expat : Changed perspectives on first language attrition in a digital era

    NARCIS (Netherlands)

    Keijzer, Merel

    2015-01-01

    L1 attrition is the (partial) language loss that is found in healthy individuals who stop routinely using their L1 after moving to an L2 environment. Over the years, the phenomenon has attracted much interest, from the general public who have (directly and indirectly) experienced attrition, but also

  10. Causes of Teacher Attrition of First, Second, and Third Year Teachers in Rural Middle Schools

    Science.gov (United States)

    Thompson, Arkeco Lashay Lewis

    2012-01-01

    Early attrition from teaching bears enormous costs. High attrition means that schools must take funds urgently needed for school improvements and spend them instead in a manner that produces little long-term payoff for student learning (Kain & Singleton, 1996). Keeping highly qualified teachers should always be at the top of the priority list…

  11. Travel time and attrition from VHA care among women veterans: how far is too far?

    Science.gov (United States)

    Friedman, Sarah A; Frayne, Susan M; Berg, Eric; Hamilton, Alison B; Washington, Donna L; Saechao, Fay; Maisel, Natalya C; Lin, Julia Y; Hoggatt, Katherine J; Phibbs, Ciaran S

    2015-04-01

    Travel time, an access barrier, may contribute to attrition of women veterans from Veterans Health Administration (VHA) care. We examined whether travel time influences attrition: (a) among women veterans overall, (b) among new versus established patients, and (c) among rural versus urban patients. This retrospective cohort study used logistic regression to estimate the association between drive time and attrition, overall and for new/established and rural/urban patients. In total, 266,301 women veteran VHA outpatients in the Fiscal year 2009. An "attriter" did not return for VHA care during the second through third years after her first 2009 visit (T0). Drive time (log minutes) was between the patient's residence and her regular source of VHA care. "New" patients had no VHA visits within 3 years before T0. Models included age, service-connected disability, health status, and utilization as covariates. Overall, longer drive times were associated with higher odds of attrition: drive time adjusted odds ratio=1.11 (99% confidence interval, 1.09-1.14). The relationship between drive time and attrition was stronger among new patients but was not modified by rurality. Attrition among women veterans is sensitive to longer drive time. Linking new patients to VHA services designed to reduce distance barriers (telemedicine, community-based clinics, mobile clinics) may reduce attrition among women new to VHA.

  12. Do Case Rates Affect Physicians' Clinical Practice in Radiation Oncology?: An Observational Study

    Science.gov (United States)

    Loy, Bryan A.; Shkedy, Clive I.; Powell, Adam C.; Happe, Laura E.; Royalty, Julie A.; Miao, Michael T.; Smith, Gary L.; Long, James W.; Gupta, Amit K.

    2016-01-01

    Case rate payments combined with utilization monitoring may have the potential to improve the quality of care by reducing over and under-treatment. Thus, a national managed care organization introduced case rate payments at one multi-site radiation oncology provider while maintaining only fee-for-service payments at others. This study examined whether the introduction of the payment method had an effect on radiation fractions administered when compared to clinical guidelines. The number of fractions of radiation therapy delivered to patients with bone metastases, breast, lung, prostate, and skin cancer was assessed for concordance with clinical guidelines. The proportion of guideline-based care ascertained from the payer's claims database was compared before (2011) and after (2013) the payment method introduction using relative risks (RR). After the introduction of case rates, there were no significant changes in guideline-based care in breast, lung, and skin cancer; however, patients with bone metastases and prostate cancer were significantly more likely to have received guideline-based care (RR = 2.0 and 1.1, respectively, ppayment model and assess implications in other populations. PMID:26870963

  13. Observation of advanced particle removal rates in pump limiter simulation experiments

    International Nuclear Information System (INIS)

    Goebel, D.M.; Conn, R.W.

    1984-05-01

    The performance of particle removal schemes for density and impurity control in tokamaks and mirror machines depends strongly on the plasma parameters and local recycling near the plasma neutralizier plates and gas pumping ducts. The relationship between plasma density, electron temperature, ion energy and gas flow and particle removal rate through a pumping duct located near a plasma neutralizer plate has been experimentally investigated in the steady state plasma device PISCES. Results indicate that initially the particle removal by pumps at the end of the duct is proportional to the plasma flux to the plate. A nonlinear increase in the pumping rate occurs when the ionization mean free path for neutrals from the plate becomes less than the plasma radius. The transition from a transparent to an opaque plasma due to local ionization of the neutrals produced at the neutralizer plate greatly enhances the particle removal rate by recycling of the neutral gas as it flows away from the neutralizer plate or out of the pumping ducts. Parameters were varied to determine the importance of ballistic scattering of higher energy ions from the plate, but no effects were found in these experiments

  14. Observation of motorcycle helmet use rates in Michigan after partial repeal of the universal motorcycle helmet law.

    Science.gov (United States)

    Buckley, Lisa; Bingham, C Raymond; Flannagan, Carol A; Carter, Patrick M; Almani, Farideh; Cicchino, Jessica B

    2016-10-01

    Motorcycle crashes result in a significant health burden, including many fatal injuries and serious non-fatal head injuries. Helmets are highly effective in preventing such trauma, and jurisdictions that require helmet use of all motorcyclists have higher rates of helmet use and lower rates of head injuries among motorcyclists. The current study examines helmet use and characteristics of helmeted operators and their riding conditions in Michigan, following a weakening of the state's universal motorcycle helmet use law in April 2012. Data on police-reported crashes occurring during 2012-14 and from a stratified roadside observational survey undertaken in Southeast Michigan during May-September 2014 were used to estimate statewide helmet use rates. Observed helmet use was more common among operators of sports motorcycles, on freeways, and in the morning, and least common among operators of cruisers, on minor arterials, and in the afternoon. The rate of helmet use across the state was estimated at 75%, adjusted for roadway type, motorcycle class, and time of day. Similarly, the helmet use rate found from examination of crash records was 73%. In the observation survey, 47% of operators wore jackets, 94% wore long pants, 54% wore boots, and 80% wore gloves. Protective clothing of jackets and gloves was most often worn by sport motorcycle operators and long pants and boots most often by riders of touring motorcycles. Findings highlight the much lower rate of helmet use in Michigan compared with states that have a universal helmet use law, although the rate is higher than observed in many states with partial helmet laws. Targeted interventions aimed at specific groups of motorcyclists and situations where helmet use rates are particularly low should be considered to increase helmet use. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Validity of observer ratings of the five-factor model of personality traits: a meta-analysis.

    Science.gov (United States)

    Oh, In-Sue; Wang, Gang; Mount, Michael K

    2011-07-01

    Conclusions reached in previous research about the magnitude and nature of personality-performance linkages have been based almost exclusively on self-report measures of personality. The purpose of this study is to address this void in the literature by conducting a meta-analysis of the relationship between observer ratings of the five-factor model (FFM) personality traits and overall job performance. Our results show that the operational validities of FFM traits based on observer ratings are higher than those based on self-report ratings. In addition, the results show that when based on observer ratings, all FFM traits are significant predictors of overall performance. Further, observer ratings of FFM traits show meaningful incremental validity over self-reports of corresponding FFM traits in predicting overall performance, but the reverse is not true. We conclude that the validity of FFM traits in predicting overall performance is higher than previously believed, and our results underscore the importance of disentangling the validity of personality traits from the method of measurement of the traits.

  16. The brief negative symptom scale: validation of the German translation and convergent validity with self-rated anhedonia and observer-rated apathy.

    Science.gov (United States)

    Bischof, Martin; Obermann, Caitriona; Hartmann, Matthias N; Hager, Oliver M; Kirschner, Matthias; Kluge, Agne; Strauss, Gregory P; Kaiser, Stefan

    2016-11-22

    Negative symptoms are considered core symptoms of schizophrenia. The Brief Negative Symptom Scale (BNSS) was developed to measure this symptomatic dimension according to a current consensus definition. The present study examined the psychometric properties of the German version of the BNSS. To expand former findings on convergent validity, we employed the Temporal Experience Pleasure Scale (TEPS), a hedonic self-report that distinguishes between consummatory and anticipatory pleasure. Additionally, we addressed convergent validity with observer-rated assessment of apathy with the Apathy Evaluation Scale (AES), which was completed by the patient's primary nurse. Data were collected from 75 in- and outpatients from the Psychiatric Hospital, University Zurich diagnosed with either schizophrenia or schizoaffective disorder. We assessed convergent and discriminant validity, internal consistency and inter-rater reliability. We largely replicated the findings of the original version showing good psychometric properties of the BNSS. In addition, the primary nurses evaluation correlated moderately with interview-based clinician rating. BNSS anhedonia items showed good convergent validity with the TEPS. Overall, the German BNSS shows good psychometric properties comparable to the original English version. Convergent validity extends beyond interview-based assessments of negative symptoms to self-rated anhedonia and observer-rated apathy.

  17. Disagreements in meta-analyses using outcomes measured on continuous or rating scales: observer agreement study

    DEFF Research Database (Denmark)

    Tendal, Britta; Higgins, Julian P T; Jüni, Peter

    2009-01-01

    difference (SMD), the protocols for the reviews and the trial reports (n=45) were retrieved. DATA EXTRACTION: Five experienced methodologists and five PhD students independently extracted data from the trial reports for calculation of the first SMD result in each review. The observers did not have access...... to the reviews but to the protocols, where the relevant outcome was highlighted. The agreement was analysed at both trial and meta-analysis level, pairing the observers in all possible ways (45 pairs, yielding 2025 pairs of trials and 450 pairs of meta-analyses). Agreement was defined as SMDs that differed less...... than 0.1 in their point estimates or confidence intervals. RESULTS: The agreement was 53% at trial level and 31% at meta-analysis level. Including all pairs, the median disagreement was SMD=0.22 (interquartile range 0.07-0.61). The experts agreed somewhat more than the PhD students at trial level (61...

  18. Improving response rates using a monetary incentive for patient completion of questionnaires: an observational study

    Directory of Open Access Journals (Sweden)

    Orchard Jo

    2007-02-01

    Full Text Available Abstract Background Poor response rates to postal questionnaires can introduce bias and reduce the statistical power of a study. To improve response rates in our trial in primary care we tested the effect of introducing an unconditional direct payment of £5 for the completion of postal questionnaires. Methods We recruited patients in general practice with knee problems from sites across the United Kingdom. An evidence-based strategy was used to follow-up patients at twelve months with postal questionnaires. This included an unconditional direct payment of £5 to patients for the completion and return of questionnaires. The first 105 patients did not receive the £5 incentive, but the subsequent 442 patients did. We used logistic regression to analyse the effect of introducing a monetary incentive to increase the response to postal questionnaires. Results The response rate following reminders for the historical controls was 78.1% (82 of 105 compared with 88.0% (389 of 442 for those patients who received the £5 payment (diff = 9.9%, 95% CI 2.3% to 19.1%. Direct payments significantly increased the odds of response (adjusted odds ratio = 2.2, 95% CI 1.2 to 4.0, P = 0.009 with only 12 of 442 patients declining the payment. The incentive did not save costs to the trial – the extra cost per additional respondent was almost £50. Conclusion The direct payment of £5 significantly increased the completion of postal questionnaires at negligible increase in cost for an adequately powered study.

  19. Improving response rates using a monetary incentive for patient completion of questionnaires: an observational study

    Science.gov (United States)

    Brealey, Stephen D; Atwell, Christine; Bryan, Stirling; Coulton, Simon; Cox, Helen; Cross, Ben; Fylan, Fiona; Garratt, Andrew; Gilbert, Fiona J; Gillan, Maureen GC; Hendry, Maggie; Hood, Kerenza; Houston, Helen; King, David; Morton, Veronica; Orchard, Jo; Robling, Michael; Russell, Ian T; Torgerson, David; Wadsworth, Valerie; Wilkinson, Clare

    2007-01-01

    Background Poor response rates to postal questionnaires can introduce bias and reduce the statistical power of a study. To improve response rates in our trial in primary care we tested the effect of introducing an unconditional direct payment of £5 for the completion of postal questionnaires. Methods We recruited patients in general practice with knee problems from sites across the United Kingdom. An evidence-based strategy was used to follow-up patients at twelve months with postal questionnaires. This included an unconditional direct payment of £5 to patients for the completion and return of questionnaires. The first 105 patients did not receive the £5 incentive, but the subsequent 442 patients did. We used logistic regression to analyse the effect of introducing a monetary incentive to increase the response to postal questionnaires. Results The response rate following reminders for the historical controls was 78.1% (82 of 105) compared with 88.0% (389 of 442) for those patients who received the £5 payment (diff = 9.9%, 95% CI 2.3% to 19.1%). Direct payments significantly increased the odds of response (adjusted odds ratio = 2.2, 95% CI 1.2 to 4.0, P = 0.009) with only 12 of 442 patients declining the payment. The incentive did not save costs to the trial – the extra cost per additional respondent was almost £50. Conclusion The direct payment of £5 significantly increased the completion of postal questionnaires at negligible increase in cost for an adequately powered study. PMID:17326837

  20. InSAR observations of low slip rates on the major faults of western Tibet.

    Science.gov (United States)

    Wright, Tim J; Parsons, Barry; England, Philip C; Fielding, Eric J

    2004-07-09

    Two contrasting views of the active deformation of Asia dominate the debate about how continents deform: (i) The deformation is primarily localized on major faults separating crustal blocks or (ii) deformation is distributed throughout the continental lithosphere. In the first model, western Tibet is being extruded eastward between the major faults bounding the region. Surface displacement measurements across the western Tibetan plateau using satellite radar interferometry (InSAR) indicate that slip rates on the Karakoram and Altyn Tagh faults are lower than would be expected for the extrusion model and suggest a significant amount of internal deformation in Tibet.

  1. Dynamic strain and rotation ground motions of the 2011 Tohoku earthquake from dense high-rate GPS observations in Taiwan

    Science.gov (United States)

    Huang, B. S.; Rau, R. J.; Lin, C. J.; Kuo, L. C.

    2017-12-01

    Seismic waves generated by the 2011 Mw 9.0 Tohoku, Japan earthquake were well recorded by continuous GPS in Taiwan. Those GPS were operated in one hertz sampling rate and densely distributed in Taiwan Island. Those continuous GPS observations and the precise point positioning technique provide an opportunity to estimate spatial derivatives from absolute ground motions of this giant teleseismic event. In this study, we process and investigate more than one and half hundred high-rate GPS displacements and its spatial derivatives, thus strain and rotations, to compare to broadband seismic and rotational sensor observations. It is shown that continuous GPS observations are highly consistent with broadband seismic observations during its surface waves across Taiwan Island. Several standard Geodesy and seismic array analysis techniques for spatial gradients have been applied to those continuous GPS time series to determine its dynamic strain and rotation time histories. Results show that those derivate GPS vertical axis ground rotations are consistent to seismic array determined rotations. However, vertical rotation-rate observations from the R1 rotational sensors have low resolutions and could not compared with GPS observations for this special event. For its dese spatial distribution of GPS stations in Taiwan Island, not only wavefield gradient time histories at individual site was obtained but also 2-D spatial ground motion fields were determined in this study also. In this study, we will report the analyzed results of those spatial gradient wavefields of the 2011 Tohoku earthquake across Taiwan Island and discuss its geological implications.

  2. Does observer bias contribute to variations in the rate of retinopathy of prematurity between centres?

    Science.gov (United States)

    Darlow, Brian A; Elder, Mark J; Horwood, L John; Donoghue, Deborah A; Henderson-Smart, David J

    2008-01-01

    We aimed to indirectly assess the contribution from observer bias to between centre variability in the incidence of acute retinopathy of prematurity (ROP). The Australian and New Zealand Neonatal Network (ANZNN) collected data on the highest stage of acute ROP in either eye in 2286 infants born at less than 29 weeks in 1998-1999 and cared for in one of 25 neonatal intensive care units (NICUs). Chi-squared analysis was used to detect differences in the proportion of stages of ROP for each neonatal intensive care unit. These proportions were compared with those reported in two large studies of treatment for ROP. The incidence of acute ROP in the ANZNN cohort was 42% and the ratio of stage 1:2:3 ROP was 1.5:1.9:1. There was considerable variation in both the incidence of acute ROP and the proportions with stage 1:2:3 ROP between centres. A chi-squared test determined that the assignment of stages 1, 2 and 3/4 ROP was not independent of centre (chi(2)(48) = 165.2; P < 0.0001). Treatment of stage 3 ROP varied between 15% and 120%, indicating some eyes were treated at less than stage 3. The data are highly suggestive of observer bias contributing to the observed between centre variation in the incidence of acute ROP. In neonatal intervention studies where acute ROP is an outcome it would seem important to have an accreditation process for examining ophthalmologists, and there are similar arguments for neonatal networks which collect these data.

  3. Strain rates estimated by geodetic observations in the Borborema Province, Brazil

    Science.gov (United States)

    Marotta, Giuliano Sant'Anna; França, George Sand; Monico, João Francisco Galera; Bezerra, Francisco Hilário R.; Fuck, Reinhardt Adolfo

    2015-03-01

    The strain rates for the Borborema Province, located in northeastern Brazil, were estimated in this study. For this purpose, we used GNSS tracking stations with a minimum of two years data. The data were processed using the software GIPSY, version 6.2, provided by the JPL of the California Institute of Technology. The PPP method was used to process the data using the non-fiducial approach. Satellite orbits and clock were supplied by the JPL. Absolute phase center offsets and variations for both the receiver and the satellite antennaes were applied, together with ambiguity resolution; corrections of the first and second order effects of the ionosphere and troposphere models adopting the VMF1 mapping function; 10° elevation mask; FES2004 oceanic load model and terrestrial tide WahrK1 PolTid FreqDepLove OctTid. From a multi annual solution, involving at least 2 years of continuous data, the coordinates and velocities as well as their accuracies were estimated. The strain rates were calculated using the Delaunay triangulation and the Finite Element Method. The results show that the velocity direction is predominantly west and north, with maximum variation of 4.0 ± 1.5 mm/year and 4.1 ± 0.5 mm/year for the x and y components, respectively. The highest strain values of extension and contraction were 0.109552 × 10-6 ± 3.65 × 10-10/year and -0.072838 × 10-6 ± 2.32 × 10-10/year, respectively. In general, the results show that the highest strain and variation of velocity values are located close to the Potiguar Basin, region that concentrates seismic activities of magnitudes of up to 5.2 mb. We conclude that the contraction direction of strain is consistent with the maximum horizontal stress derived from focal mechanism and breakout data. In addition, we conclude that the largest strain rates occur around the Potiguar Basin, an area already recognized as one of the major sites of seismicity in intraplate South America.

  4. Observational study of the relationship between entrainment rate and relative dispersion in deep convective clouds

    Science.gov (United States)

    Guo, Xiaohao; Lu, Chunsong; Zhao, Tianliang; Liu, Yangang; Zhang, Guang Jun; Luo, Shi

    2018-01-01

    This study investigates the influence of entrainment rate (λ) on relative dispersion (ε) of cloud droplet size distributions (CDSD) in the 99 growing precipitating deep convective clouds during TOGA-COARE. The results show that entrainment suppresses ε, which is opposite to the traditional understanding that entrainment-mixing broadens CDSD. To examine how the relationship between ε and λ is affected by droplets with different sizes, CDSDs are divided into three portions with droplet radius processes is developed to illustrate the possible scenarios entailing different relationships between ε and λ. The number concentration of small droplets and the degree of evaporation of small droplets are found to be key factors that shift the sign (i.e., positive or negative) of the ε-λ relationship.

  5. Empirically observed learning rates for concentrating solar power and their responses to regime change

    Science.gov (United States)

    Lilliestam, Johan; Labordena, Mercè; Patt, Anthony; Pfenninger, Stefan

    2017-07-01

    Concentrating solar power (CSP) capacity has expanded slower than other renewable technologies and its costs are still high. Until now, there have been too few CSP projects to derive robust conclusions about its cost development. Here we present an empirical study of the cost development of all operating CSP stations and those under construction, examining the roles of capacity growth, industry continuity, and policy support design. We identify distinct CSP expansion phases, each characterized by different cost pressure in the policy regime and different industry continuity. In 2008-2011, with low cost pressure and following industry discontinuity, costs increased. In the current phase, with high cost pressure and continuous industry development, costs decreased rapidly, with learning rates exceeding 20%. Data for projects under construction suggest that this trend is continuing and accelerating. If support policies and industrial structure are sustained, we see no near-term factors that would hinder further cost decreases.

  6. CU-STARs: Promoting STEM Diversity by Addressing First-year Attrition of Underrepresented Minorities

    Science.gov (United States)

    Battersby, Cara; Silvia, Devin W.; Ellingson, Erica; Sturner, Andrew P.; Peck, Courtney

    2015-01-01

    Upon first entering university, the fraction of students interested in pursuing a STEM major are distributed according to societal demographics (with 25% being underrepresented minorities), but by graduation, the fraction of students receiving STEM degrees is unbalanced, with underrepresented minorities receiving only 15% of STEM bachelor's degrees. The CU-STARs (CU Science, Technology, and Astronomy Recruits) program at the University of Colorado, Boulder is targeted to address the main triggers of early career attrition for underrepresented minorities in STEM disciplines. A select group of students are given financial support through work-study at the Fiske planetarium on campus, while resources to address other triggers of attrition are available to the entire cohort of interested students (typically ~5-10 per year). These resources are designed to promote social engagement and mentorship, while also providing a support network and resources to combat inadequate high school preparation for STEM courses. We achieve these goals through activities that include social events, mentor meetings, free tutoring, and special events to meet and talk with scientists. The culmination of the program for the recruits are a series of high school outreach events in underserved areas (inner city and rural alike), in which they become the expert. The STARs are paid for their time and take the lead in planning, teaching, and facilitating programs for the high school students, including classroom presentations, interactive lab activities, solar observing, and star parties. The high school outreach events provide role models and STEM exposure for the underserved high school community while simultaneously cementing the personal achievements and successes for the STARs. CU-STARs is now in its 4th year and is still growing. We are beginning the process of formal assessments of the program's success. We present details of the program implementation, a discussion of potential obstacles

  7. Sludge Settling Rate Observations and Projections at the Savannah River Site - 13238

    Energy Technology Data Exchange (ETDEWEB)

    Gillam, Jeffrey M.; Shah, Hasmukh B.; Keefer, Mark T. [Savannah River Remediation LLC, Aiken SC 29808 (United States)

    2013-07-01

    Since 2004, sludge batches have included a high percentage of stored sludge generated from the H- modified (HM) process. The slow-settling nature of HM sludge means that the settling is often the major part of the washing tank quiescent period between required pump runs to maintain flammability control. Reasonable settling projections are needed to wash soluble salts from sludge in an efficient manner, to determine how much sludge can be washed in a batch within flammability limits, and to provide composition projections for batch qualification work done in parallel with field preparation. Challenges to providing reasonably accurate settling projections include (1) large variations in settling behavior from tank-to-tank, (2) accounting for changing initial concentrations, sludge masses, and combinations of different sludge types, (3) changing the settling behavior upon dissolving some sludge compounds, and (4) sludge preparation schedules that do not allow for much data collection for a particular sludge before washing begins. Scaling from laboratory settling tests has provided inconsistent results. Several techniques have been employed to improve settling projections and therefore the overall batch preparation efficiency. Before any observations can be made on a particular sludge mixture, projections can only be made based on historical experience with similar sludge types. However, scaling techniques can be applied to historical settling models to account for different sludge masses, concentrations, and even combinations of types of sludge. After sludge washing/settling cycles begin, the direct measurement of the sludge height, once generally limited to a single turbidity meter measurement per settle period, is now augmented by examining the temperature profile in the settling tank, to help determine the settled sludge height over time. Recently, a settling model examined at PNNL [1,2,3] has been applied to observed thermocouple and turbidity meter readings to

  8. Relationship between interplanetary parameters and the magnetopause reconnection rate quantified from observations of the expanding polar cap

    Science.gov (United States)

    Milan, S. E.; Gosling, J. S.; Hubert, B.

    2012-03-01

    Many studies have attempted to quantify the coupling of energy from the solar wind into the magnetosphere. In this paper we parameterize the dependence of the magnetopause reconnection rate on interplanetary parameters from the OMNI data set. The reconnection rate is measured as the rate of expansion of the polar cap during periods when the nightside reconnection rate is thought to be low, determined from observations by the Imager for Magnetopause-to-Aurora Global Exploration (IMAGE) Far Ultraviolet (FUV) imager. Our fitting suggests that the reconnection rate is determined by the magnetic flux transport in the solar wind across a channel approximately 4 RE in width, with a small correction dependent on the solar wind speed, and a clock angle dependence. The reconnection rate is not found to be significantly dependent on the solar wind density. Comparison of the modeled reconnection rate with SuperDARN measurements of the cross-polar cap potential provides broad support for the magnitude of the predictions. In the course of the paper we discuss the relationship between the dayside reconnection rate and the cross-polar cap potential.

  9. Parameterization of ion-induced nucleation rates based on ambient observations

    Directory of Open Access Journals (Sweden)

    T. Nieminen

    2011-04-01

    Full Text Available Atmospheric ions participate in the formation of new atmospheric aerosol particles, yet their exact role in this process has remained unclear. Here we derive a new simple parameterization for ion-induced nucleation or, more precisely, for the formation rate of charged 2-nm particles. The parameterization is semi-empirical in the sense that it is based on comprehensive results of one-year-long atmospheric cluster and particle measurements in the size range ~1–42 nm within the EUCAARI (European Integrated project on Aerosol Cloud Climate and Air Quality interactions project. Data from 12 field sites across Europe measured with different types of air ion and cluster mobility spectrometers were used in our analysis, with more in-depth analysis made using data from four stations with concomitant sulphuric acid measurements. The parameterization is given in two slightly different forms: a more accurate one that requires information on sulfuric acid and nucleating organic vapor concentrations, and a simpler one in which this information is replaced with the global radiation intensity. These new parameterizations are applicable to all large-scale atmospheric models containing size-resolved aerosol microphysics, and a scheme to calculate concentrations of sulphuric acid, condensing organic vapours and cluster ions.

  10. Tropical cyclone turbulent mixing as observed by autonomous oceanic profilers with the high repetition rate

    International Nuclear Information System (INIS)

    Baranowski, D B; Malinowski, S P; Flatau, P J

    2011-01-01

    Changes in the ocean mixed layer caused by passage of two consecutive typhoons in the Western Pacific are presented. Ocean profiles were measured by a unique Argo float sampling the upper ocean in high repetition cycle with a period of about one day. It is shown that the typhoon passage coincides with cooling of the mixed layer and variations of its salinity. Independent data from satellite measurements of surface winds were used to set-up an and idealized numerical simulation of mixed layer evolution. Results, compared to Argo profiles, confirm known effect that cooling is a result of increased entrainment from the thermocline due to enhancement of turbulence in the upper ocean by the wind stress. Observed pattern of salinity changes in the mixed layer suggest important role of typhoon precipitation. Fast changes of the mixed layer in course of typhoon passage show that fast profiling (at least once a day) is crucial to study response of the upper ocean to tropical cyclone.

  11. Attrition during a randomized controlled trial of reduced nicotine content cigarettes as a proxy for understanding acceptability of nicotine product standards.

    Science.gov (United States)

    Mercincavage, Melissa; Wileyto, E Paul; Saddleson, Megan L; Lochbuehler, Kirsten; Donny, Eric C; Strasser, Andrew A

    2017-06-01

    To determine (1) if nicotine content affects study attrition-a potential behavioral measure of acceptability-in a trial that required compliance with three levels of reduced nicotine content (RNC) cigarettes, and (2) if attrition is associated with subjective and behavioral responses to RNC cigarettes. Secondary analysis of a 35-day, parallel-design, open-label, randomized controlled trial. After a 5-day baseline period, participants were randomized to smoke for three 10-day periods: their preferred brand (control group) or RNC cigarettes with three nicotine levels in a within-subject stepdown (one group: high-moderate-low) or non-stepdown (five groups: high-low-moderate, low-moderate-high, low-high-moderate, moderate-low-high, moderate-high-low) fashion. A single site in Philadelphia, PA, USA. A total of 246 non-treatment-seeking daily smokers [mean age = 39.52, cigarettes per day (CPD) = 20.95, 68.3% white] were recruited from October 2007 to June 2013. The primary outcome was attrition. Key predictors were nicotine content transition and study period. Exploratory predictors were taste and strength subjective ratings, total puff volume and carbon monoxide (CO) boost. Covariates included: age, gender, race, education and nicotine dependence. Overall attrition was 31.3% (n = 77): 24.1% of the control and 25.0% of the stepdown RNC cigarette groups dropped out versus 44.6% of non-stepdown groups (P = 0.006). Compared with controls, attrition odds were 4.5 and 4.7 times greater among smokers transitioning from preferred and the highest RNC cigarettes to the lowest RNC cigarettes, respectively (P = 0.001 and 0.003). Providing more favorable initial taste ratings of study cigarettes decreased attrition odds by 2% (P = 0.012). The majority of participants completed a 35-day trial of varying levels of reduced nicotine content cigarettes. Participant dropout was greater for cigarettes with lower nicotine content and less in smokers reporting more favorable

  12. Associations between informant ratings of personality disorder traits, self-reports of personality, and directly observed behavior.

    Science.gov (United States)

    Kaurin, Aleksandra; Sauerberger, Kyle S; Funder, David C

    2018-03-02

    Diagnoses of personality disorders (PD) must rely on judgments of observers-either clinicians or acquaintances-because personality disorders are primarily defined in terms of maladaptive interpersonal behavior. Little is known, however, about how closely acquaintances' judgments of PD traits relate to self-reports of theoretically relevant Big Five traits or directly observed behavioral outcomes in interpersonal situations. The present study examines associations between judgments of the 10 PD traits provided by close acquaintances, self-reports of PD-relevant Big Five personality traits, and observed interpersonal behaviors across three different three-person laboratory interactions (i.e., unstructured chat, cooperative task, competitive game). The sample consisted of 256 undergraduate students (130 females; M age  = 19.83, SD = 1.25). Four unacquainted observers independently rated participants' behaviors from video recordings. In line with previous work, informant reports of PD traits demonstrate strong convergent validity with relevant self-reported Big Five traits (as identified by Lynam & Widiger, 2001). Directly observed behavior is meaningfully associated with acquaintances' judgments and self-reports of PD-relevant traits, and the associations between these judgments and behavior are strongest for traits associated with histrionic and schizoid PD. Vector correlations between behavioral profiles associated with informant and self-reports show that both assessments have similar behavioral correlates. Associations between PD trait ratings and behavior appeared to differ as a function of gender, with males showing more and stronger correlations. Informants' ratings of PD traits are impressively accurate, converging both with self-reports of relevant traits and directly observed interpersonal behavior. Therefore, a comprehensive understanding of PDs and associated traits can be augmented by information from multiple acquaintances who have the

  13. Electromagnetic energy deposition rate in the polar upper thermosphere derived from the EISCAT Svalbard radar and CUTLASS Finland radar observations

    Directory of Open Access Journals (Sweden)

    H. Fujiwara

    2007-11-01

    Full Text Available From simultaneous observations of the European incoherent scatter Svalbard radar (ESR and the Cooperative UK Twin Located Auroral Sounding System (CUTLASS Finland radar on 9 March 1999, we have derived the height distributions of the thermospheric heating rate at the F region height in association with electromagnetic energy inputs into the dayside polar cap/cusp region. The ESR and CUTLASS radar observations provide the ionospheric parameters with fine time-resolutions of a few minutes. Although the geomagnetic activity was rather moderate (Kp=3+~4, the electric field obtained from the ESR data sometimes shows values exceeding 40 mV/m. The estimated passive energy deposition rates are also larger than 150 W/kg in the upper thermosphere over the ESR site during the period of the enhanced electric field. In addition, enhancements of the Pedersen conductivity also contribute to heating the upper thermosphere, while there is only a small contribution for thermospheric heating from the direct particle heating due to soft particle precipitation in the dayside polar cap/cusp region. In the same period, the CUTLASS observations of the ion drift show the signature of poleward moving pulsed ionospheric flows with a recurrence rate of about 10–20 min. The estimated electromagnetic energy deposition rate shows the existence of the strong heat source in the dayside polar cap/cusp region of the upper thermosphere in association with the dayside magnetospheric phenomena of reconnections and flux transfer events.

  14. Electromagnetic energy deposition rate in the polar upper thermosphere derived from the EISCAT Svalbard radar and CUTLASS Finland radar observations

    Directory of Open Access Journals (Sweden)

    H. Fujiwara

    2007-11-01

    Full Text Available From simultaneous observations of the European incoherent scatter Svalbard radar (ESR and the Cooperative UK Twin Located Auroral Sounding System (CUTLASS Finland radar on 9 March 1999, we have derived the height distributions of the thermospheric heating rate at the F region height in association with electromagnetic energy inputs into the dayside polar cap/cusp region. The ESR and CUTLASS radar observations provide the ionospheric parameters with fine time-resolutions of a few minutes. Although the geomagnetic activity was rather moderate (Kp=3+~4, the electric field obtained from the ESR data sometimes shows values exceeding 40 mV/m. The estimated passive energy deposition rates are also larger than 150 W/kg in the upper thermosphere over the ESR site during the period of the enhanced electric field. In addition, enhancements of the Pedersen conductivity also contribute to heating the upper thermosphere, while there is only a small contribution for thermospheric heating from the direct particle heating due to soft particle precipitation in the dayside polar cap/cusp region. In the same period, the CUTLASS observations of the ion drift show the signature of poleward moving pulsed ionospheric flows with a recurrence rate of about 10–20 min. The estimated electromagnetic energy deposition rate shows the existence of the strong heat source in the dayside polar cap/cusp region of the upper thermosphere in association with the dayside magnetospheric phenomena of reconnections and flux transfer events.

  15. Are Final Comments in Web Survey Panels Associated with Next-Wave Attrition?

    Directory of Open Access Journals (Sweden)

    Cynthia McLauchlan

    2016-12-01

    Full Text Available Near the end of a web survey respondents are often asked whether they have further comments. Such final comments are usually ignored, in part because open-ended questions are challenging to analyse. We explored whether final comments are associated with next-wave attrition in survey panels. We categorized a random sample of final comments in the Longitudinal Studies for the Social Sciences (LISS panel and Dutch Immigrant panel into one of eight categories (neutral, positive, six subcategories of negative and regressed the indicator of next-wave attrition on comment length, comment category and socio-demographic variables. In the Immigrant panel we found shorter final comments (55 words with decreased next-wave attrition relative to making no comment. Comments about unclear survey questions quadruple the odds of attrition and “other” (uncategorized negative comments almost double the odds of attrition. In the LISS panel, making a comment (vs. not and comment length are not associated with attrition. However, when specifying individual comment categories, neutral comments are associated with half the odds of attrition relative to not making a comment.

  16. Ascertainment of the effect of differential growth rates of mutants on observed mutant frequencies in X-irradiated mammalian cells

    International Nuclear Information System (INIS)

    Knaap, A.G.A.C.; Simons, J.W.I.M.

    1983-01-01

    As it is not known to what extent differential growth rates of induced mutants lead to over- and under-representation of mutants in treated populations and thereby affect the determination of mutant frequencies, the mutation induction in X-irradiated L5178Y mouse lymphoma cells was determined via two methods. The first method involves the standard protocol which may suffer from the effect of differential growth rates, while the second method is based upon the fluctuation test in which the differential growth rates can be actually measured. It appeared that the standard protocol led to a mutant frequency that was similar to the mutant frequency determined in the fluctuation test. Therefore, the standard protocol appears to lead to only a minor under-estimation if any. Substantial heterogeneity in growth rates of induced mutants was observed, but the mutants with a selective advantage appear largely to compensate for the mutants that are lost because of selective disadvantage. It was calculated that the chance for isolating the same mutant twice from a treated population had been increased 2.2-fold because of the observed differential growth rates. (orig./AJ)

  17. Experimental investigation of attrition resistance of zeolite catalysts in two particle gas-solid-solid fluidization system

    International Nuclear Information System (INIS)

    Nawaz, Z.; Ziaoping, T.; Shu, Q.; Wei, F.; Naveed, S.

    2010-01-01

    In the study of mechanical degradation of 34 ZSM-5 and SAPO catalysts, using the gas jet attrition - ASTM standard fluidized bed test (D-5757), the effect of particle size and its quantitative analysis in co-fluidization environment was investigated on the air jet index (AJI) basis. In gas-solid-solid fluidized bed reactors (GSS-FBR), two different sized particles were fluidized under isothermal conditions. In case of ZSM-5 and SAPO-34, significant attrition resistance was observed, which was attributed to small pore size and specific structural strength of the mobile framework image (MFI) and chabasite (CHA) structures, respectively. The optimum AJI for SAPO-34 and ZSM-5 (of particle size 0.2 mm) in GSS-fluidization system was observed to be 0.0118 and 0.0062, respectively. In co-fluidization, deviations from Gwyn relationship were observed due to change in impact of collision. Therefore, zeolites are recommended as suitable catalysts or catalytic supports (for doping of expensive metals) and for commercial use in GSS-FBR. (author)

  18. OBSERVER RATING VERSUS THREE-DIMENSIONAL MOTION ANALYSIS OF LOWER EXTREMITY KINEMATICS DURING FUNCTIONAL SCREENING TESTS: A SYSTEMATIC REVIEW.

    Science.gov (United States)

    Maclachlan, Liam; White, Steven G; Reid, Duncan

    2015-08-01

    Functional assessments are conducted in both clinical and athletic settings in an attempt to identify those individuals who exhibit movement patterns that may increase their risk of non-contact injury. In place of highly sophisticated three-dimensional motion analysis, functional testing can be completed through observation. To evaluate the validity of movement observation assessments by summarizing the results of articles comparing human observation in real-time or video play-back and three-dimensional motion analysis of lower extremity kinematics during functional screening tests. Systematic review. A computerized systematic search was conducted through Medline, SPORTSdiscus, Scopus, Cinhal, and Cochrane health databases between February and April of 2014. Validity studies comparing human observation (real-time or video play-back) to three-dimensional motion analysis of functional tasks were selected. Only studies comprising uninjured, healthy subjects conducting lower extremity functional assessments were appropriate for review. Eligible observers were certified health practitioners or qualified members of sports and athletic training teams that conduct athlete screening. The Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) was used to appraise the literature. Results are presented in terms of functional tasks. Six studies met the inclusion criteria. Across these studies, two-legged squats, single-leg squats, drop-jumps, and running and cutting manoeuvres were the functional tasks analysed. When compared to three-dimensional motion analysis, observer ratings of lower extremity kinematics, such as knee position in relation to the foot, demonstrated mixed results. Single-leg squats achieved target sensitivity values (≥ 80%) but not specificity values (≥ 50%>%). Drop-jump task agreement ranged from poor ( 80%). Two-legged squats achieved 88% sensitivity and 85% specificity. Mean underestimations as large as 198 (peak knee flexion) were found in

  19. Gender-related differences in outcomes and attrition on antiretroviral treatment among an HIV-infected patient cohort in Zimbabwe: 2007–2010

    Directory of Open Access Journals (Sweden)

    Kudakwashe C. Takarinda

    2015-01-01

    Conclusions: Our findings show that males presented late for ART initiation compared to females. Similar to other studies, males had higher patient attrition and mortality compared to females and this may be attributed in part to late presentation for HIV treatment and care. These observations highlight the need to encourage early HIV testing and enrolment into HIV treatment and care, and eventually patient retention on ART, particularly amongst men.

  20. Description, evaluation and clinical decision making according to various fetal heart rate patterns. Inter-observer and regional variability

    DEFF Research Database (Denmark)

    Lidegaard, O; Bøttcher, L M; Weber, Tom

    1992-01-01

    departments, especially between departments far apart. It is concluded that we still need a scientific clarification of which specific heart rate changes are the best predictors of fetal stress. Artificial intelligence programs for interpreting fetal cardiotocograms and ECG signals constitute one promising......At 10 Danish obstetrical departments, 116 residents (42 senior and 74 junior) participated in a study to assess inter-observer and regional variability in the description and evaluation of and clinical decision regarding 11 fetal heart rate patterns. The 11 traces included normal as well...... as pathological patterns, and normal as well as clinically asphyxiated babies. Five antepartum and six intrapartum patterns were included. A total of 1,276 descriptions and evaluations were obtained. The degree of agreement in description of fetal heart rate changes was high regarding the baseline...

  1. Accuracy of a Wrist-Worn Wearable Device for Monitoring Heart Rates in Hospital Inpatients: A Prospective Observational Study.

    Science.gov (United States)

    Kroll, Ryan R; Boyd, J Gordon; Maslove, David M

    2016-09-20

    As the sensing capabilities of wearable devices improve, there is increasing interest in their application in medical settings. Capabilities such as heart rate monitoring may be useful in hospitalized patients as a means of enhancing routine monitoring or as part of an early warning system to detect clinical deterioration. To evaluate the accuracy of heart rate monitoring by a personal fitness tracker (PFT) among hospital inpatients. We conducted a prospective observational study of 50 stable patients in the intensive care unit who each completed 24 hours of heart rate monitoring using a wrist-worn PFT. Accuracy of heart rate recordings was compared with gold standard measurements derived from continuous electrocardiographic (cECG) monitoring. The accuracy of heart rates measured by pulse oximetry (Spo2.R) was also measured as a positive control. On a per-patient basis, PFT-derived heart rate values were slightly lower than those derived from cECG monitoring (average bias of -1.14 beats per minute [bpm], with limits of agreement of 24 bpm). By comparison, Spo2.R recordings produced more accurate values (average bias of +0.15 bpm, limits of agreement of 13 bpm, P<.001 as compared with PFT). Personal fitness tracker device performance was significantly better in patients in sinus rhythm than in those who were not (average bias -0.99 bpm vs -5.02 bpm, P=.02). Personal fitness tracker-derived heart rates were slightly lower than those derived from cECG monitoring in real-world testing and not as accurate as Spo2.R-derived heart rates. Performance was worse among patients who were not in sinus rhythm. Further clinical evaluation is indicated to see if PFTs can augment early warning systems in hospitals. ClinicalTrials.gov NCT02527408; https://clinicaltrials.gov/ct2/show/NCT02527408 (Archived by WebCite at  http://www.webcitation.org/6kOFez3on).

  2. LOW FALSE POSITIVE RATE OF KEPLER CANDIDATES ESTIMATED FROM A COMBINATION OF SPITZER AND FOLLOW-UP OBSERVATIONS

    International Nuclear Information System (INIS)

    Désert, Jean-Michel; Brown, Timothy M.; Charbonneau, David; Torres, Guillermo; Fressin, François; Ballard, Sarah; Latham, David W.; Bryson, Stephen T.; Borucki, William J.; Knutson, Heather A.; Batalha, Natalie M.; Deming, Drake; Ford, Eric B.; Fortney, Jonathan J.; Gilliland, Ronald L.; Seager, Sara

    2015-01-01

    NASA’s Kepler mission has provided several thousand transiting planet candidates during the 4 yr of its nominal mission, yet only a small subset of these candidates have been confirmed as true planets. Therefore, the most fundamental question about these candidates is the fraction of bona fide planets. Estimating the rate of false positives of the overall Kepler sample is necessary to derive the planet occurrence rate. We present the results from two large observational campaigns that were conducted with the Spitzer Space Telescope during the the Kepler mission. These observations are dedicated to estimating the false positive rate (FPR) among the Kepler candidates. We select a sub-sample of 51 candidates, spanning wide ranges in stellar, orbital, and planetary parameter space, and we observe their transits with Spitzer at 4.5 μm. We use these observations to measures the candidate’s transit depths and infrared magnitudes. An authentic planet produces an achromatic transit depth (neglecting the modest effect of limb darkening). Conversely a bandpass-dependent depth alerts us to the potential presence of a blending star that could be the source of the observed eclipse: a false positive scenario. For most of the candidates (85%), the transit depths measured with Kepler are consistent with the transit depths measured with Spitzer as expected for planetary objects, while we find that the most discrepant measurements are due to the presence of unresolved stars that dilute the photometry. The Spitzer constraints on their own yield FPRs between 5% and depending on the Kepler Objects of Interest. By considering the population of the Kepler field stars, and by combining follow-up observations (imaging) when available, we find that the overall FPR of our sample is low. The measured upper limit on the FPR of our sample is 8.8% at a confidence level of 3σ. This observational result, which uses the achromatic property of planetary transit signals that is not investigated

  3. LOW FALSE POSITIVE RATE OF KEPLER CANDIDATES ESTIMATED FROM A COMBINATION OF SPITZER AND FOLLOW-UP OBSERVATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Désert, Jean-Michel; Brown, Timothy M. [CASA, Department of Astrophysical and Planetary Sciences, University of Colorado, 389-UCB, Boulder, CO 80309 (United States); Charbonneau, David; Torres, Guillermo; Fressin, François; Ballard, Sarah; Latham, David W. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Bryson, Stephen T.; Borucki, William J. [NASA Ames Research Center, Moffett Field, CA 94035 (United States); Knutson, Heather A. [Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125 (United States); Batalha, Natalie M. [San Jose State University, San Jose, CA 95192 (United States); Deming, Drake [Department of Astronomy, University of Maryland, College Park, MD 20742-2421 (United States); Ford, Eric B. [University of Florida, Gainesville, FL 32611 (United States); Fortney, Jonathan J. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Gilliland, Ronald L. [Center for Exoplanets and Habitable Worlds, The Pennsylvania State University, University Park, PA 16802 (United States); Seager, Sara, E-mail: desert@colorado.edu [Massachusetts Institute of Technology, Cambridge, MA 02159 (United States)

    2015-05-01

    NASA’s Kepler mission has provided several thousand transiting planet candidates during the 4 yr of its nominal mission, yet only a small subset of these candidates have been confirmed as true planets. Therefore, the most fundamental question about these candidates is the fraction of bona fide planets. Estimating the rate of false positives of the overall Kepler sample is necessary to derive the planet occurrence rate. We present the results from two large observational campaigns that were conducted with the Spitzer Space Telescope during the the Kepler mission. These observations are dedicated to estimating the false positive rate (FPR) among the Kepler candidates. We select a sub-sample of 51 candidates, spanning wide ranges in stellar, orbital, and planetary parameter space, and we observe their transits with Spitzer at 4.5 μm. We use these observations to measures the candidate’s transit depths and infrared magnitudes. An authentic planet produces an achromatic transit depth (neglecting the modest effect of limb darkening). Conversely a bandpass-dependent depth alerts us to the potential presence of a blending star that could be the source of the observed eclipse: a false positive scenario. For most of the candidates (85%), the transit depths measured with Kepler are consistent with the transit depths measured with Spitzer as expected for planetary objects, while we find that the most discrepant measurements are due to the presence of unresolved stars that dilute the photometry. The Spitzer constraints on their own yield FPRs between 5% and depending on the Kepler Objects of Interest. By considering the population of the Kepler field stars, and by combining follow-up observations (imaging) when available, we find that the overall FPR of our sample is low. The measured upper limit on the FPR of our sample is 8.8% at a confidence level of 3σ. This observational result, which uses the achromatic property of planetary transit signals that is not investigated

  4. Planned home compared with planned hospital births: mode of delivery and Perinatal mortality rates, an observational study.

    Science.gov (United States)

    van der Kooy, Jacoba; Birnie, Erwin; Denktas, Semiha; Steegers, Eric A P; Bonsel, Gouke J

    2017-06-08

    To compare the mode of delivery between planned home versus planned hospital births and to determine if differences in intervention rates could be interpreted as over- or undertreatment. Intervention and perinatal mortality rates were obtained for 679,952 low-risk women from the Dutch Perinatal Registry (2000-2007). Intervention was defined as operative vaginal delivery and/or caesarean section. Perinatal mortality was defined as the intrapartum and early neonatal mortality rate up to 7 days postpartum. Besides adjustment for maternal and care factors, we included for additional casemix adjustment: presence of congenital abnormality, small for gestational age, preterm birth, or low Apgar score. The techniques used were nested multiple stepwise logistic regression, and stratified analysis for separate risk groups. An intention-to-treat like analysis was performed. The intervention rate was lower in planned home compared to planned hospital births (10.9% 95% CI 10.8-11.0 vs. 13.8% 95% CI 13.6-13.9). Intended place of birth had significant impact on the likelihood to intervene after adjustment (planned homebirth (OR 0.77 95% CI. 0.75-0.78)). The mortality rate was lower in planned home births (0.15% vs. 0.18%). After adjustment, the interaction term home- intervention was significant (OR1.51 95% CI 1.25-1.84). In risk groups, a higher perinatal mortality rate was observed in planned home births. The potential presence of over- or under treatment as expressed by adjusted perinatal mortality differs per risk group. In planned home births especially multiparous women showed universally lower intervention rates. However, the benefit of substantially fewer interventions in the planned home group seems to be counterbalanced by substantially increased mortality if intervention occurs.

  5. Health worker attrition at a rural district hospital in Rwanda: a need ...

    African Journals Online (AJOL)

    Health worker attrition at a rural district hospital in Rwanda: a need for improved placement and retention strategies. Jackline Odhiambo, Felix Cyamatare Rwabukwisi, Christian Rusangwa, Vincent Rusanganwa, Lisa Ruth Hirschhorn, Evrard Nahimana, Patient Ngamije, Bethany Lynn Hedt-Gauthier ...

  6. Initial Entry Training: Reducing First Term Attrition Through Effective Organizational Socialization

    National Research Council Canada - National Science Library

    Hayden, Thomas

    2000-01-01

    This paper examines Initial Entry Training (IET) from an organizational behavior perspective to identify if the Army's socialization experience can be enhanced to have a positive impact on first term attrition within the Army...

  7. Risk Attitudes, Sample Selection and Attrition in a Longitudinal Field Experiment

    DEFF Research Database (Denmark)

    Harrison, Glenn W.; Lau, Morten Igel

    with respect to risk attitudes. Our design builds in explicit randomization on the incentives for participation. We show that there are significant sample selection effects on inferences about the extent of risk aversion, but that the effects of subsequent sample attrition are minimal. Ignoring sample...... selection leads to inferences that subjects in the population are more risk averse than they actually are. Correcting for sample selection and attrition affects utility curvature, but does not affect inferences about probability weighting. Properly accounting for sample selection and attrition effects leads...... to findings of temporal stability in overall risk aversion. However, that stability is around different levels of risk aversion than one might naively infer without the controls for sample selection and attrition we are able to implement. This evidence of “randomization bias” from sample selection...

  8. A Longitudinal Examination of First Term Attrition and Reenlistment among FY1999 Enlisted Accessions

    National Research Council Canada - National Science Library

    Strickland, William J

    2005-01-01

    .... This effort allowed the evaluation of models of attrition and reenlistment intentions based on information contained in personnel records and collected from Soldiers who were surveyed as they entered...

  9. Analysis of Recruit Attrition from the Navy's Delayed Entry Program and Recruit Training Command

    National Research Council Canada - National Science Library

    Neuhalfen, Jon K

    2007-01-01

    .... The analysis uses the PRIDE database, provided by Commander, Navy Recruiting Command. Trend analyses are used to identify significant changes in enlistment and attrition behavior for recruits who joined from fiscal years 1998 through 2005...

  10. The Role of Personality Type on Minority Attrition at the US Naval Academy

    Science.gov (United States)

    2002-06-01

    Provost as more likely to attrite were ISTP, ESTP, ISFP, and ENFJ . “These students tend to be less organized, more passive in their relationship to...MBTI ISTP ISTJ ISFP ISFJ INTP INTJ INFP INFJ ESTP ESTJ ESFP ESFJ ENTP ENTJ ENFP ENFJ C ou nt 400 300 200 100 0 33 Table 12: Minority Attrition...reason to believe that all who are admitted have the potential to graduate. B. PURPOSE OF STUDY This thesis examines the relationship

  11. The impact of attrition on the representativeness of cohort studies of older people

    Directory of Open Access Journals (Sweden)

    Brilleman Samuel L

    2010-08-01

    Full Text Available Abstract Background There are well-established risk factors, such as lower education, for attrition of study participants. Consequently, the representativeness of the cohort in a longitudinal study may deteriorate over time. Death is a common form of attrition in cohort studies of older people. The aim of this paper is to examine the effects of death and other forms of attrition on risk factor prevalence in the study cohort and the target population over time. Methods Differential associations between a risk factor and death and non-death attrition are considered under various hypothetical conditions. Empirical data from the Australian Longitudinal Study on Women's Health (ALSWH for participants born in 1921-26 are used to identify associations which occur in practice, and national cross-sectional data from Australian Censuses and National Health Surveys are used to illustrate the evolution of bias over approximately ten years. Results The hypothetical situations illustrate how death and other attrition can theoretically affect changes in bias over time. Between 1996 and 2008, 28.4% of ALSWH participants died, 16.5% withdrew and 10.4% were lost to follow up. There were differential associations with various risk factors, for example, non-English speaking country of birth was associated with non-death attrition but not death whereas being underweight (body mass index Conclusions Deaths occur in both the target population and study cohort, while other forms of attrition occur only in the study cohort. Therefore non-death attrition may cause greater bias than death in longitudinal studies. However although more than a quarter of the oldest participants in the ALSWH died in the 12 years following recruitment, differences from the national population changed only slightly.

  12. Flotability Improvement of Ilmenite Using Attrition-Scrubbing as a Pretreatment Method

    Directory of Open Access Journals (Sweden)

    Jihua Zhai

    2017-01-01

    Full Text Available Flotation technology of the recovery and utilization of ilmenite from tailings of iron beneficiated in Panzhihua was investigated based on mineralogical study. The results of mineralogical study show that the main occurrence of the valuable mineral are liberated grains of ilmenite. Experimental results of flotation conditions show that attrition-scrubbing raw ores exhibit good flotability with higher recoveries and a slight decrease in grade compared to ores without attrition-scrubbing. Further, open-circuit experiments also prove the superiority of attrition-scrubbing raw ores. The results of closed-circuit experiments show that qualified ilmenite concentrate can be obtained and the yield, grade, and recovery are 22.26%, 47.06%, and 60.73%, respectively. Theoretical study and analysis show that there are two contributions to superior flotability for attrition-scrubbing samples. The first is that the attrition-scrubbing samples can uncover more ferrous ions on the newly-produced fresh ilmenite surface, resulting in the increase in active sites. The other is that in the process of attrition-scrubbing, the transformation of ferrous ions to ferric ions can be promoted.

  13. Selective attrition and intraindividual variability in response time moderate cognitive change.

    Science.gov (United States)

    Yao, Christie; Stawski, Robert S; Hultsch, David F; MacDonald, Stuart W S

    2016-01-01

    Selection of a developmental time metric is useful for understanding causal processes that underlie aging-related cognitive change and for the identification of potential moderators of cognitive decline. Building on research suggesting that time to attrition is a metric sensitive to non-normative influences of aging (e.g., subclinical health conditions), we examined reason for attrition and intraindividual variability (IIV) in reaction time as predictors of cognitive performance. Three hundred and four community dwelling older adults (64-92 years) completed annual assessments in a longitudinal study. IIV was calculated from baseline performance on reaction time tasks. Multilevel models were fit to examine patterns and predictors of cognitive change. We show that time to attrition was associated with cognitive decline. Greater IIV was associated with declines on executive functioning and episodic memory measures. Attrition due to personal health reasons was also associated with decreased executive functioning compared to that of individuals who remained in the study. These findings suggest that time to attrition is a useful metric for representing cognitive change, and reason for attrition and IIV are predictive of non-normative influences that may underlie instances of cognitive loss in older adults.

  14. Weight Loss Expectations and Attrition in Treatment-Seeking Obese Women

    Directory of Open Access Journals (Sweden)

    Riccardo Dalle Grave

    2015-10-01

    Full Text Available Objective: The analysis of the relation between weight loss goals and attrition in the treatment of obesity has produced conflicting results. The aim of the present study was to investigate the role of weight loss goals on attrition in a cohort of obese women seeking treatment at 8 Italian medical centres. Methods: 634 women with obesity, consecutively enrolled in weight loss programmes, were included in the study. Weight loss goals were evaluated with the Goals and Relative Weights Questionnaire (GRWQ, reporting a sequence of unrealistic (‘dream' and ‘happy' and more realistic (‘acceptable' and ‘disappointing' weight loss goals. Attrition was assessed at 12 months on the basis of patients' medical records. Results: At 12 months, 205/634 patients (32.3% had interrupted their programme and were lost to follow-up. After adjustment for age, baseline weight, education and employment status, attrition was significantly associated with higher percent acceptable and disappointing weight loss targets, not with dream and happy weight loss. Conclusion: In ‘real world' clinical settings, only realistic expectations might favour attrition whenever too challenging, whereas unrealistic weight loss goals have no effect. Future studies should assess the effect of interventions aimed at coping with too challenging weight goals on attrition.

  15. Physician experience and rates of plasma HIV-1 RNA suppression among illicit drug users: an observational study

    Directory of Open Access Journals (Sweden)

    Sangsari Sassan

    2012-01-01

    Full Text Available Abstract Background Despite the availability of antiretroviral therapy (ART, suboptimal treatment outcomes have been observed among HIV-seropositive illicit drug users. As there is an urgent need to improve responses to antiretroviral therapy among this population, we undertook this study to evaluate the role of physician experience on rates of plasma HIV-1 RNA suppression following initiation of ART. Methods Using data from a community-recruited cohort of HIV-positive illicit drug users, we used Cox proportional hazards regression to model the time to plasma viral HIV RNA Results Between May 1996 and December 2008, 267 individuals initiated ART among whom 227 (85% achieved a plasma HIV RNA Conclusions In this setting of universal HIV/AIDS care, illicit drug users with more experienced physicians exhibited faster rates of plasma viral load suppression. These findings argue for specialized services to help optimize HIV treatment outcomes among this population.

  16. A Qualitative Evaluation of Engagement and Attrition in a Nurse Home Visiting Program: From the Participant and Provider Perspective.

    Science.gov (United States)

    Beasley, Lana O; Ridings, Leigh E; Smith, Tyler J; Shields, Jennifer D; Silovsky, Jane F; Beasley, William; Bard, David

    2018-05-01

    Beginning parenting programs in the prenatal and early postnatal periods have a large potential for impact on later child and maternal outcomes. Home-based parenting programs, such as the Nurse Family Partnership (NFP), have been established to help address this need. Program reach and impact is dependent on successful engagement of expecting mothers with significant risks; however, NFP attrition rates remain high. The current study qualitatively examined engagement and attrition from the perspectives of NFP nurses and mothers in order to identify mechanisms that enhance service engagement. Semi-structured interviews were conducted in focus groups composed of either engaged (27 total mothers) or unengaged (15 total mothers) mothers from the NFP program. NFP nurses (25 total nurses) were recruited for individual semi-structured interviews. Results suggest that understanding engagement in the NFP program requires addressing both initial and sustained engagement. Themes associated with enhanced initial engagement include nurse characteristics (e.g., flexible, supportive, caring) and establishment of a solid nurse-family relationship founded on these characteristics. Factors impacting sustained engagement include nurse characteristics, provision of educational materials on child development, individualized services for families, and available family support. Identified barriers to completing services include competing demands and lack of support. Findings of this study have direct relevance for workforce planning, including hiring and training through integrating results regarding effective nurse characteristics. Additional program supports to enhance parent engagement may be implemented across home-based parenting programs in light of the current study's findings.

  17. A comparison of the predicted and observed reaction rates of various neutron detectors in a thermal reactor spectrum

    International Nuclear Information System (INIS)

    Hardiman, J.P.; Maunders, E.J.

    1963-08-01

    A number of the detectors commonly used in integral neutron spectrum measurements have been irradiated in the pitch moderator position of a Calder Hall lattice where the detailed energy spectrum is known from time of flight measurements. Predicted and observed reaction rates are generally in good agreement although they are brought into better agreement by a small modification to the spectrum. The predicted cadmium ratios are quite sensitive to the value adopted for the effective cadmium cut off energy, values of which were determined for various detectors using the Ferranti Mercury computer. The values varied over a wide range, although in every case only 40 mil. cadmium filters were used. (author)

  18. Stratospheric mean ages and transport rates from observations of CO{sub 2} and N{sub 2}O

    Energy Technology Data Exchange (ETDEWEB)

    Boering, K A; Wofsy, S C; Daube, B C; Schneider, H R [Harvard Univ., Cambridge, MA (United States). Div. of Engineering and Applied Sciences; Loewenstein, M; Podolske, J R [NASA Ames Research Center, Moffett Field, CA (United States); Conway, T J [National Oceanic and Atmospheric Administration, Boulder, CO (United States)

    1998-12-31

    Measurements of CO{sub 2} and N{sub 2}O concentrations are reported and analyzed to investigate stratospheric transport rates. Temporal variations in tropospheric CO{sub 2} are observed to propagate into the stratosphere, showing that tropospheric air enters the lower tropical stratosphere continuously, ascends, and is transported rapidly (in less than 1 month) to both hemispheres. The mean age of stratospheric air determined from CO{sub 2} data is approximately 5 years in the mid-stratosphere. It is shown that the mean age is mathematically equivalent to a conserved tracer analogous to exhaust from stratospheric aircraft. Comparison of the mean age from models and observations indicates that current model simulations likely underestimate pollutant concentrations from proposed stratospheric aircraft by 25-100%. (author) 36 refs.

  19. Stratospheric mean ages and transport rates from observations of CO{sub 2} and N{sub 2}O

    Energy Technology Data Exchange (ETDEWEB)

    Boering, K.A.; Wofsy, S.C.; Daube, B.C.; Schneider, H.R. [Harvard Univ., Cambridge, MA (United States). Div. of Engineering and Applied Sciences; Loewenstein, M.; Podolske, J.R. [NASA Ames Research Center, Moffett Field, CA (United States); Conway, T.J. [National Oceanic and Atmospheric Administration, Boulder, CO (United States)

    1997-12-31

    Measurements of CO{sub 2} and N{sub 2}O concentrations are reported and analyzed to investigate stratospheric transport rates. Temporal variations in tropospheric CO{sub 2} are observed to propagate into the stratosphere, showing that tropospheric air enters the lower tropical stratosphere continuously, ascends, and is transported rapidly (in less than 1 month) to both hemispheres. The mean age of stratospheric air determined from CO{sub 2} data is approximately 5 years in the mid-stratosphere. It is shown that the mean age is mathematically equivalent to a conserved tracer analogous to exhaust from stratospheric aircraft. Comparison of the mean age from models and observations indicates that current model simulations likely underestimate pollutant concentrations from proposed stratospheric aircraft by 25-100%. (author) 36 refs.

  20. Tone Attrition in Mandarin Speakers of Varying English Proficiency

    Science.gov (United States)

    Creel, Sarah C.

    2017-01-01

    Purpose The purpose of this study was to determine whether the degree of dominance of Mandarin–English bilinguals' languages affects phonetic processing of tone content in their native language, Mandarin. Method We tested 72 Mandarin–English bilingual college students with a range of language-dominance profiles in the 2 languages and ages of acquisition of English. Participants viewed 2 photographs at a time while hearing a familiar Mandarin word referring to 1 photograph. The names of the 2 photographs diverged in tone, vowels, or both. Word recognition was evaluated using clicking accuracy, reaction times, and an online recognition measure (gaze) and was compared in the 3 conditions. Results Relative proficiency in English was correlated with reduced word recognition success in tone-disambiguated trials, but not in vowel-disambiguated trials, across all 3 dependent measures. This selective attrition for tone content emerged even though all bilinguals had learned Mandarin from birth. Lengthy experience with English thus weakened tone use. Conclusions This finding has implications for the question of the extent to which bilinguals' 2 phonetic systems interact. It suggests that bilinguals may not process pitch information language-specifically and that processing strategies from the dominant language may affect phonetic processing in the nondominant language—even when the latter was learned natively. PMID:28124064

  1. Heart rate and leukocytes after air and ground transportation in artificially ventilated neonates: a prospective observational study.

    Science.gov (United States)

    Grosek, Stefan; Mlakar, Gorazd; Vidmar, Ivan; Ihan, Alojz; Primozic, Janez

    2009-01-01

    To evaluate the effect of interhospital air and ground transportation of artificially ventilated neonates on heart rate and peripheral blood leukocyte counts. Prospective, observational study. Level III multidisciplinary Neonatal and Pediatric Intensive Care Unit. Fifty-eight near-term artificially ventilated transported neonates between May 2006 and April 2007. Day-helicopter, day- and night-ground transportation. Heart rate at retrieval, on admission to the ICU and 1 h later, and peripheral blood leukocyte counts on admission and 1 d later were compared. Fifteen neonates were transported by helicopter during the daytime (D-HEL), 20 by daytime ground and 23 by nighttime ground transportation (D-GROUND, N-GROUND). No differences in delivery mode, birth weight, gestational age, gender, primary diagnoses for transportation, response time and duration of transportation were found between the groups. Similarly, no differences in pH, pCO(2), blood pressure and skin temperature at retrieval and on admission to the ICU were found between the three groups. The mean heart rate at retrieval did not differ significantly, while on arrival in the ICU and 1 h later the D-GROUND group of patients showed a significantly higher mean heart rate compared to the D-HEL and N-GROUND groups. Moreover, leukocyte counts on arrival in the ICU showed significantly higher leukocyte counts in the D-GROUND group of patients compared to the D-HEL group of patients. These results demonstrate that there is an association between daytime ground transportation and higher heart rate and peripheral blood leukocytes.

  2. Laboratory observations of temperature and humidity dependencies of nucleation and growth rates of sub-3 nm particles

    Science.gov (United States)

    Yu, Huan; Dai, Liang; Zhao, Yi; Kanawade, Vijay P.; Tripathi, Sachchida N.; Ge, Xinlei; Chen, Mindong; Lee, Shan-Hu

    2017-02-01

    Temperature and relative humidity (RH) are the most important thermodynamic parameters in aerosol formation, yet laboratory studies of nucleation and growth dependencies on temperature and RH are lacking. Here we report the experimentally observed temperature and RH dependences of sulfuric acid aerosol nucleation and growth. Experiments were performed in a flow tube in the temperature range from 248 to 313 K, RH from 0.8% to 79%, and relative acidity (RA) of sulfuric acid from 6 × 10-5 to 0.38 (2 × 107-109 cm-3). The impurity levels of base compounds were determined to be NH3 nucleation at fixed sulfuric acid concentration but impede nucleation when RA is fixed. It is also shown that binary nucleation of sulfuric acid and water is negligible in planetary boundary layer temperature and sulfuric acid ranges. An empirical algorithm was derived to correlate the nucleation rate with RA, RH, and temperature together. Collision-limited condensation of free-sulfuric acid molecules fails to predict the observed growth rate in the sub-3 nm size range, as well as its dependence on temperature and RH. This suggests that evaporation, sulfuric acid hydration, and possible involvement of other ternary molecules should be considered for the sub-3 nm particle growth.

  3. Estimating radar reflectivity - snowfall rate relationships and their uncertainties over Antarctica by combining disdrometer and radar observations

    Science.gov (United States)

    Souverijns, Niels; Gossart, Alexandra; Lhermitte, Stef; Gorodetskaya, Irina; Kneifel, Stefan; Maahn, Maximilian; Bliven, Francis; van Lipzig, Nicole

    2017-04-01

    The Antarctic Ice Sheet (AIS) is the largest ice body on earth, having a volume equivalent to 58.3 m global mean sea level rise. Precipitation is the dominant source term in the surface mass balance of the AIS. However, this quantity is not well constrained in both models and observations. Direct observations over the AIS are also not coherent, as they are sparse in space and time and acquisition techniques differ. As a result, precipitation observations stay mostly limited to continent-wide averages based on satellite radar observations. Snowfall rate (SR) at high temporal resolution can be derived from the ground-based radar effective reflectivity factor (Z) using information about snow particle size and shape. Here we present reflectivity snowfall rate relations (Z = aSRb) for the East Antarctic escarpment region using the measurements at the Princess Elisabeth (PE) station and an overview of their uncertainties. A novel technique is developed by combining an optical disdrometer (NASA's Precipitation Imaging Package; PIP) and a vertically pointing 24 GHz FMCW micro rain radar (Metek's MRR) in order to reduce the uncertainty in SR estimates. PIP is used to obtain information about snow particle characteristics and to get an estimate of Z, SR and the Z-SR relation. For PE, located 173 km inland, the relation equals Z = 18SR1.1. The prefactor (a) of the relation is sensitive to the median diameter of the particles. Larger particles, found closer to the coast, lead to an increase of the value of the prefactor. More inland locations, where smaller snow particles are found, obtain lower values for the prefactor. The exponent of the Z-SR relation (b) is insensitive to the median diameter of the snow particles. This dependence of the prefactor of the Z-SR relation to the particle size needs to be taken into account when converting radar reflectivities to snowfall rates over Antarctica. The uncertainty on the Z-SR relations is quantified using a bootstrapping approach

  4. Further Insight into the Effectiveness of a Behavioral Teacher Program Targeting ADHD Symptoms Using Actigraphy, Classroom Observations and Peer Ratings.

    Science.gov (United States)

    Veenman, Betty; Luman, Marjolein; Oosterlaan, Jaap

    2017-01-01

    Objective: The Positivity and Rules program (PR program), a low-level behavioral teacher program targeting symptoms of attention-deficit/hyperactivity disorder (ADHD), has shown positive effects on teacher-rated ADHD symptoms and social functioning. This study aimed to assess whether program effects could be confirmed by instruments assessing classroom behavior other than teacher-ratings, given teachers' involvement with the training. Methods: Participants were 114 primary school children (age = 6-13) displaying ADHD symptoms in the classroom, who were randomly assigned to the treatment ( n = 58) or control group ( n = 65). ADHD symptoms were measured using classroom observations and actigraphy, and peer acceptance was measured using peer ratings. Intention-to-treat multilevel analyses were conducted to assess program effects. Results: No beneficial program effects were found for any of the measures. Conclusion: The earlier beneficial program effects on both ADHD symptoms and social functioning reported by teachers, may be explained by a change in the perception of teachers rather than changes in the child's behavior. Other methodological explanations are also discussed, such as differences between instruments in the sensitivity to program-related changes. The current study underlines the importance of using different measures of classroom behavior to study program effects. ClinicalTrials.gov registration number: NCT02518711.

  5. Kalman Filtering and Smoothing of the Van Allen Probes Observations to Estimate the Radial, Energy and Pitch Angle Diffusion Rates

    Science.gov (United States)

    Podladchikova, T.; Shprits, Y.; Kellerman, A. C.

    2015-12-01

    The Kalman filter technique combines the strengths of new physical models of the Earth's radiation belts with long-term spacecraft observations of electron fluxes and therefore provide an extremely useful method for the analysis of the state and evolution of the electron radiation belts. However, to get the reliable data assimilation output, the Kalman filter application is confronted with a set of fundamental problems. E.g., satellite measurements are usually limited to a single location in space, which confines the reconstruction of the global evolution of the radiation environment. The uncertainties arise from the imperfect description of the process dynamics and the presence of observation errors, which may cause the failure of data assimilation solution. The development of adaptive Kalman filter that combines the Van Allen Probes data and 3-D VERB code, its accurate customizations in the reconstruction of model describing the phase space density (PSD) evolution, extension of the possibilities to use measurement information, and the model adjustment by developing the identification techniques of model and measurement errors allowed us to reveal hidden and implicit regularities of the PSD dynamics and obtain quantitative and qualitative estimates of radial, energy and pitch angle diffusion characteristics from satellite observations. In this study we propose an approach to estimate radial, energy and pitch angle diffusion rates, as well as the direction of their propagation.

  6. The Fukushima releases: an inverse modelling approach to assess the source term by using gamma dose rate observations

    Science.gov (United States)

    Saunier, Olivier; Mathieu, Anne; Didier, Damien; Tombette, Marilyne; Quélo, Denis; Winiarek, Victor; Bocquet, Marc

    2013-04-01

    The Chernobyl nuclear accident and more recently the Fukushima accident highlighted that the largest source of error on consequences assessment is the source term estimation including the time evolution of the release rate and its distribution between radioisotopes. Inverse modelling methods have proved to be efficient to assess the source term due to accidental situation (Gudiksen, 1989, Krysta and Bocquet, 2007, Stohl et al 2011, Winiarek et al 2012). These methods combine environmental measurements and atmospheric dispersion models. They have been recently applied to the Fukushima accident. Most existing approaches are designed to use air sampling measurements (Winiarek et al, 2012) and some of them use also deposition measurements (Stohl et al, 2012, Winiarek et al, 2013). During the Fukushima accident, such measurements are far less numerous and not as well distributed within Japan than the dose rate measurements. To efficiently document the evolution of the contamination, gamma dose rate measurements were numerous, well distributed within Japan and they offered a high temporal frequency. However, dose rate data are not as easy to use as air sampling measurements and until now they were not used in inverse modelling approach. Indeed, dose rate data results from all the gamma emitters present in the ground and in the atmosphere in the vicinity of the receptor. They do not allow one to determine the isotopic composition or to distinguish the plume contribution from wet deposition. The presented approach proposes a way to use dose rate measurement in inverse modeling approach without the need of a-priori information on emissions. The method proved to be efficient and reliable when applied on the Fukushima accident. The emissions for the 8 main isotopes Xe-133, Cs-134, Cs-136, Cs-137, Ba-137m, I-131, I-132 and Te-132 have been assessed. The Daiichi power plant events (such as ventings, explosions…) known to have caused atmospheric releases are well identified in

  7. Forms of Attrition in a Longitudinal Study of Religion and Health in Older Adults and Implications for Sample Bias.

    Science.gov (United States)

    Hayward, R David; Krause, Neal

    2016-02-01

    The use of longitudinal designs in the field of religion and health makes it important to understand how attrition bias may affect findings in this area. This study examines attrition in a 4-wave, 8-year study of older adults. Attrition resulted in a sample biased toward more educated and more religiously involved individuals. Conditional linear growth curve models found that trajectories of change for some variables differed among attrition categories. Ineligibles had worsening depression, declining control, and declining attendance. Mortality was associated with worsening religious coping styles. Refusers experienced worsening depression. Nevertheless, there was no evidence of bias in the key religion and health results.

  8. Predicting Attrition, Performance, Reenlistment, and Hospitalizations from the Smoking History of Women Prior to Entering the Navy

    National Research Council Canada - National Science Library

    Conway, Terry L

    2006-01-01

    This study of women sailors examined whether tobacco use prior to entering the Navy predicted subsequent career outcomes related to length of service, early attrition, misconduct, and hospitalizations...

  9. Inter-observer variation in estimates by nuclear angiography of left ventricular ejection fraction and ejection rate

    International Nuclear Information System (INIS)

    Young, K.C.; Railton, R.

    1980-01-01

    The recent decline in the cost of computing has led to the introduction of data processing of gamma-camera images in many medical centres, allowing the development and widespread use of radionuclide techniques for assessing left ventricular performance. Methods such as ECG-gated blood-pool imaging have the advantage of being less invasive than contrast ventriculography and do not rely on geometrical assumptions about the shape of the ventricle. A study has been made of the inter-observer variation in estimates of ejection fraction and average and maximum systolic contraction rates using a micro-computer (VIP-450 Video Image Processor, Ohio-Nuclear Limited, Rugby) to analyse gated blood-pool images of the left ventricle. (author)

  10. Climatology of the Occurrence Rate and Amplitudes of Local Time Distinguished Equatorial Plasma Depletions Observed by Swarm Satellite

    Science.gov (United States)

    Wan, Xin; Xiong, Chao; Rodriguez-Zuluaga, Juan; Kervalishvili, Guram N.; Stolle, Claudia; Wang, Hui

    2018-04-01

    In this study, we developed an autodetection technique for the equatorial plasma depletions (EPDs) and their occurrence and depletion amplitudes based on in situ electron density measurements gathered by Swarm A satellite. For the first time, comparisons are made among the detected EPDs and their amplitudes with the loss of Global Positioning System (GPS) signal of receivers onboard Swarm A, and the Swarm Level-2 product, Ionospheric Bubble Index (IBI). It has been found that the highest rate of EPD occurrence takes place generally between 2200 and 0000 magnetic local time (MLT), in agreement with the IBI. However, the largest amplitudes of EPD are detected earlier at about 1900-2100 MLT. This coincides with the moment of higher background electron density and the largest occurrence of GPS signal loss. From a longitudinal perspective, the higher depletion amplitude is always witnessed in spatial bins with higher background electron density. At most longitudes, the occurrence rate of postmidnight EPDs is reduced compared to premidnight ones; while more postmidnight EPDs are observed at African longitudes. CHAMP observations confirm this point regardless of high or low solar activity condition. Further by comparing with previous studies and the plasma vertical drift velocity from ROCSAT-1, we suggest that while the F region vertical plasma drift plays a key role in dominating the occurrence of EPDs during premidnight hours, the postmidnight EPDs are the combined results from the continuing of former EPDs and newborn EPDs, especially during June solstice. And these newborn EPDs during postmidnight hours seem to be less related to the plasma vertical drift.

  11. The relationship between experimental geometry, heat rate, and ultrasound wave speed measurement while observing phase changes in highly attenuative materials

    Science.gov (United States)

    Moore, David G.; Stair, Sarah L.; Jack, David A.

    2018-04-01

    Ultrasound techniques are capable of monitoring changes in the time-of-flight as a material is exposed to different thermal environments. The focus of the present study is to identify the phase of a material via ultrasound compression wave measurements in a through transmission experimental setup as the material is heated from a solid to a liquid and then allowed to re-solidify. The present work seeks to expand upon the authors' previous research, which proved this through transmission phase monitoring technique was possible, by considering different experimental geometries. The relationship between geometry, the measured speed of sound, and the temperature profile is presented. The use of different volumes helps in establishing a baseline understanding of which aspects of the experiment are geometry dependent and which are independent. The present study also investigates the relationship between the heating rate observed in the experiment and the measured speed of sound. The trends identified between the experimental geometry, heat rate and ultrasound wave speed measurement assist in providing a baseline understanding of the applicability of this technique to various industries, including the polymer industry and the oil industry.

  12. The Rates of Type I X-ray Bursts from Transients Observed with RXTE: Evidence for Black Hole Event Horizons

    Science.gov (United States)

    Remillard, R. A.; Lin, D.; Cooper, R. L.; Narayan, R.

    2005-12-01

    We measure the rates of type I X-ray bursts from a likely complete sample of 37 non-pulsing Galactic X-ray transients observed with the RXTE ASM during 1996-2004. Our strategy is to test the prevailing paradigms for these sources, which are well-categorized in the literature as either neutron-star systems or black hole candidates. Burst rates are measured as a function of the bolometric luminosity, and the results are compared with burst models for neutron stars and for heavy compact objects with a solid surface. We use augmented versions of the models developed by Narayan & Heyl (2002; 2003). For a given mass, we consider a range of conditions in both the radius and the temperature at the boundary below the accretion layer. We find 135 type I bursts in 3.7 Ms of PCA light curves for the neutron-star group, and the burst rate function is generally consistent with the model predictions for bursts from accreting neutron stars. On the other hand, none of the (20) bursts candidates passed spectral criteria for type I bursts in 6.5 Ms of PCA light curves for black-hole binaries and candidates. The burst function upper limits are inconsistent with the predictions of the burst model for heavy compact objects with a solid surface. The consistency probability is found to be below 10-7 for dynamical black-hole binaries, falling to below 10-13 for the additional exposures of black-hole candidates. These results provide indirect evidence that black holes do have event horizons. This research was supported, in part, by NASA science programs.

  13. DEVELOPMENT OF ATTRITION RESISTANT IRON-BASED FISCHER-TROPSCH CATALYSTS

    International Nuclear Information System (INIS)

    Adeyinka A. Adeyiga

    2001-01-01

    The Fischer-Tropsch (F-T) reaction provides a way of converting coal-derived synthesis gas (CO+H 2 ) to liquid fuels. Since the reaction is highly exothermic, one of the major problems in control of the reaction is heat removal. Recent work has shown that the use of slurry bubble column reactors (SBCRs) can largely solve this problem. The use of iron-based catalysts is attractive not only due to their low cost and ready availability, but also due to their high water-gas shift activity which makes it possible to use these catalysts with low H 2 /CO ratios. However, a serious problem with use of Fe catalysts in a SBCR is their tendency to undergo attrition. This can cause fouling/plugging of downstream filters and equipment, makes the separation of catalyst from the oil/wax product very difficult if not impossible, and results in a steady loss of catalyst from the reactor. Recently, fundamental understanding of physical attrition is being addressed by incorporating suitable binders into the catalyst recipe. This has resulted in the preparation of a spray dried Fe-based catalyst having aps of 70 mm with high attrition resistance. This Fe-based attrition resistant, active and selective catalyst gave 95% CO conversion through 125 hours of testing in a fixed-bed at 270 C, 1.48 MPa, H 2 /CO=0.67 and 2.0 NL/g-cat/h with C 5 + selectivity of >78% and methane selectivity of <5%. However, further development of the catalyst is needed to address the chemical attrition due to phase changes that any Fe-catalyst goes through potentially causing internal stresses within the particle and resulting in weakening, spalling or cracking. The objective of this research is to develop robust iron-based Fischer-Tropsch catalysts that have suitable activity, selectivity and stability to be used in the slurry bubble column reactor. Specifically we aim to develop to: (i) improve the performance and preparation procedure of the high activity, high attrition resistant, high alpha iron

  14. Attitudes and factors contributing to attrition in Canadian surgical specialty residency programs.

    Science.gov (United States)

    Adams, Simon; Ginther, David Nathan; Neuls, Evan; Hayes, Paul

    2017-08-01

    We recently studied attrition in Canadian general surgical programs; however, there are no data on whether residents enrolled in other surgical residencies harbour the same intents as their general surgical peers. We sought to determine how many residents in surgical disciplines in Canada consider leaving their programs and why. An anonymous survey was administered to all residents in 9 surgical disciplines in Canada. Significance of association was determined using the Pearson χ2 test. The Canadian Post-MD Education Registry (CAPER) website was used to calculate the response rate. We received 523 responses (27.6% response rate). Of these respondents, 140 (26.8%) were either "somewhat" or "seriously" considering leaving their program. Residents wanting to pursue additional fellowship training and those aspiring to an academic career were significantly less likely to be considering changing specialties ( p = 0.003 and p = 0.005, respectively). Poor work-life balance and fear of unemployment/underemployment were the top reasons why residents would change specialty (55.5% and 40.8%, respectively), although the reasons cited were not significantly different between those considering changing and those who were not ( p = 0.64). Residents who were considering changing programs were significantly less likely to enjoy their work and more likely to cite having already invested too much time to change as a reason for continuing ( p work-life balance and limited employment prospects. Efforts to educate prospective residents about the reality of the surgical lifestyle and to optimize employment prospects may improve completion rates.

  15. Bounding the effects of social experiments: accounting for attrition in administrative data.

    Science.gov (United States)

    Grogger, Jeffrey

    2012-12-01

    Social experiments frequently exploit data from administrative records. However, most administrative data systems are designed to track earnings or benefit payments among residents within a single state. When an experimental participant moves across state lines, his entries in the data system of his state of origin consist entirely of zeros. Such attrition may bias the estimated effect of the experiment. To estimate the attrition arising from interstate mobility and provide bounds on the effect of the experiment. Attrition is estimated from runs of zeros at the end of the sample period. Bounds are constructed from these estimates. These estimates can be refined by imposing a stationarity assumption. The width of the estimated bounds depends importantly on the nature of the data being analyzed. Negatively correlated outcomes provide tighter bounds than positively correlated outcomes. Attrition can introduce considerable ambiguity into the estimated effects of experimental programs. To reduce ambiguity, one should collect as much data as possible. Even data on outcomes of no direct interest to the objectives of the experiment may be valuable for reducing the ambiguity that arises due to attrition.

  16. Personality Disorder in Adult Attention-Deficit/Hyperactivity Disorder: Attrition and Change During Long-term Treatment.

    Science.gov (United States)

    Gift, Thomas E; Reimherr, Frederick W; Marchant, Barrie K; Steans, Tammy A; Wender, Paul H

    2016-05-01

    Personality disorders (PDs) are commonly found in adults with attention-deficit/hyperactivity disorder (ADHD) and are associated with increased ADHD symptoms and psychosocial impairment. To assess the impact of PDs or personality traits on retention rates in ADHD trials and whether treating ADHD affects the expression of PD, data were analyzed from 2 methylphenidate trials. Assessment of PDs and personality traits included using the Wisconsin Personality Disorders Inventory IV and the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition Personality Disorders. Attention-deficit/hyperactivity disorder symptoms were evaluated using the Wender-Reimherr Adult Attention Deficit Disorder Scale. Major findings were that subjects with cluster A, cluster B, passive-aggressive, or more than 1 PD showed more attrition. Subjects dropping out also had more schizoid and narcissistic traits. Attention-deficit/hyperactivity disorder symptoms (p Disorders Inventory IV items that improved most, 8 resembled ADHD or oppositional defiant disorder symptoms.

  17. Why do faculty leave? Reasons for attrition of women and minority faculty from a medical school: four-year results.

    Science.gov (United States)

    Cropsey, Karen L; Masho, Saba W; Shiang, Rita; Sikka, Veronica; Kornstein, Susan G; Hampton, Carol L

    2008-09-01

    Faculty attrition, particularly among female and minority faculty, is a serious problem in academic medical settings. The reasons why faculty in academic medical settings choose to leave their employment are not well understood. Further, it is not clear if the reasons why women and minority faculty leave differ from those of other groups. One hundred sixty-six medical school faculty who left the School of Medicine (SOM) between July 1, 2001, and June 30, 2005, completed a survey about their reasons for leaving. The three most common overall reasons for leaving the institution included career/professional advancement (29.8%), low salary (25.5%), and chairman/departmental leadership issues (22.4%). The ranking of these reasons varied slightly across racial and gender groups, with women and minority faculty also citing personal reasons for leaving. Women and minority faculty were at lower academic ranks at the time they left the SOM compared with male and majority groups. Although salary differences were not present at the time of initial hire, sex was a significant predictor of lower salary at the start of the new position. Opportunity for advancement and the rate of promotion were significantly different between women and men. Job characteristics prior to leaving that were rated most poorly were protected time for teaching and research, communication across the campus, and patient parking. Harassment and discrimination were reported by a small number of those surveyed, particularly women and minority faculty. The majority of reasons for faculty attrition are amenable to change. Retaining high-quality faculty in medical settings may justify the costs of faculty development and retention efforts.

  18. Particle Separation of Non-Decontamination Soil using Attrition and Washing

    International Nuclear Information System (INIS)

    Koo, Daeseo; Sung, Hyun-Hee; Kim, Seung-Soo; Hong, Sang Bum; Seo, Bum Kyoung; Choi, Jong-Won

    2017-01-01

    In this study, to improve the decontamination efficiency of uranium soil, a preliminary experiment on the particle separation of non-decontamination soil was carried out using attrition and washing. The characteristics of the attrition and washing system are investigated. A conditional experiment on particle separation of non-decontamination soil will be performed. A preliminary experiment on the particle separation of non-decontamination soil was carried out to improve the decontamination efficiency of uranium soil. This experiment was performed with the ratio of soil to water (1:4) for the particle separation of non-decontamination soil. The operations of all equipment such as attrition scrubber, ultrasonic reaction, vibrating screen, and hydro-cyclone were conducted and confirmed. In the future, the additional experiments will be conducted for optimal experimental condition.

  19. The implications of selective attrition for estimates of intergenerational elasticity of family income.

    Science.gov (United States)

    Schoeni, Robert F; Wiemers, Emily E

    2015-09-01

    Numerous studies have estimated a high intergenerational correlation in economic status. Such studies do not typically attend to potential biases that may arise due to survey attrition. Using the Panel Study of Income Dynamics - the data source most commonly used in prior studies - we demonstrate that attrition is particularly high for low-income adult children with low-income parents and particularly low for high-income adult children with high-income parents. Because of this pattern of attrition, intergenerational upward mobility has been overstated for low-income families and downward mobility has been understated for high-income families. The bias among low-income families is greater than the bias among high-income families implying that intergenerational elasticity in family income is higher than previous estimates with the Panel Study of Income Dynamics would suggest.

  20. Surface mechanical attrition treatment of tungsten and its behavior under low energy deuterium plasma implantation relevant to ITER divertor conditions

    Energy Technology Data Exchange (ETDEWEB)

    Xu, H.Y.; Yuan, Y.; Fu, B.Q.; Godfrey, A.; Liu, W. [Tsinghua Univ.. Lab. of Advanced Materials, Beijing (China); Zhang, Y.B. [Technical Univ. og Denmark. DTU Risoe Campus, Roskilde (Denmark); Tao, N.R. [Chinese Academy of Sciences, Shenyang (China)

    2012-11-01

    In the light of a foreseen application for tungsten (W) as an ITER divertor material samples have been plastically deformed by a surface mechanical attrition treatment (SMAT) and by cold rolling. The resistance to blister formation by low energy deuterium implantation in these samples has been examined, with the result that the structure is significantly improved as the structural scale is reduced to the nanometer range in the SMAT sample. The distribution of blisters in this sample is however bimodal, due to the formation of several very large blisters, which are heterogeneously distributed. The observations suggest that process optimization must be a next step in the development with a view to the application of plastically deformed W in a fusion reactor. (Author)

  1. Localized solid-state amorphization at grain boundaries in a nanocrystalline Al solid solution subjected to surface mechanical attrition

    Energy Technology Data Exchange (ETDEWEB)

    Wu, X [State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100080 (China); Tao, N [Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016 (China); Hong, Y [State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100080 (China); Lu, J [LASMIS, University of Technology of Troyes, 10000, Troyes (France); Lu, K [Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016 (China)

    2005-11-21

    Using high-resolution electron microscopy, localized solid-state amorphization (SSA) was observed in a nanocrystalline (NC) Al solid solution (weight per cent 4.2 Cu, 0.3 Mn, the rest being Al) subjected to a surface mechanical attrition treatment. It was found that the deformation-induced SSA may occur at the grain boundary (GB) where either the high density dislocations or dislocation complexes are present. It is suggested that lattice instability due to elastic distortion within the dislocation core region plays a significant role in the initiation of the localized SSA at defective sites. Meanwhile, the GB of severely deformed NC grains exhibits a continuously varying atomic structure in such a way that while most of the GB is ordered but reveals corrugated configurations, localized amorphization may occur along the same GB.

  2. Patient attrition from the HIV antiretroviral therapy program at two hospitals in Haiti.

    Science.gov (United States)

    Puttkammer, Nancy H; Zeliadt, Steven B; Baseman, Janet G; Destiné, Rodney; Wysler Domerçant, Jean; Labbé Coq, Nancy Rachel; Atwood Raphael, Nernst; Sherr, Kenneth; Tegger, Mary; Yuhas, Krista; Barnhart, Scott

    2014-10-01

    To identify factors associated with antiretroviral therapy (ART) attrition among patients initiating therapy in 2005-2011 at two large, public-sector department-level hospitals, and to inform interventions to improve ART retention. This retrospective cohort study used data from the iSanté electronic medical record (EMR) system. The study characterized ART attrition levels and explored the patient demographic, clinical, temporal, and service utilization factors associated with ART attrition, using time-to-event analysis methods. Among the 2 023 patients in the study, ART attrition on average was 17.0 per 100 person-years (95% confidence interval (CI): 15.8-18.3). In adjusted analyses, risk of ART attrition was up to 89% higher for patients living in distant communes compared to patients living in the same commune as the hospital (hazard ratio: 1.89, 95%CI: 1.54-2.33; P Hospital site, earlier year of ART start, spending less time enrolled in HIV care prior to ART initiation, receiving a non-standard ART regimen, lacking counseling prior to ART initiation, and having a higher body mass index were also associated with attrition risk. The findings suggest quality improvement interventions at the two hospitals, including: enhanced retention support and transportation subsidies for patients accessing care from remote areas; counseling for all patients prior to ART initiation; timely outreach to patients who miss ART pick-ups; "bridging services" for patients transferring care to alternative facilities; routine screening for anticipated interruptions in future ART pick-ups; and medical case review for patients placed on non-standard ART regimens. The findings are also relevant for policymaking on decentralization of ART services in Haiti.

  3. Patient attrition from the HIV antiretroviral therapy program at two hospitals in Haiti

    Directory of Open Access Journals (Sweden)

    Nancy H. Puttkammer

    2014-10-01

    Full Text Available OBJECTIVE: To identify factors associated with antiretroviral therapy (ART attrition among patients initiating therapy in 2005-2011 at two large, public-sector department-level hospitals, and to inform interventions to improve ART retention. METHODS: This retrospective cohort study used data from the iSanté electronic medical record (EMR system. The study characterized ART attrition levels and explored the patient demographic, clinical, temporal, and service utilization factors associated with ART attrition, using time-to-event analysis methods. RESULTS: Among the 2 023 patients in the study, ART attrition on average was 17.0 per 100 person-years (95% confidence interval (CI: 15.8-18.3. In adjusted analyses, risk of ART attrition was up to 89% higher for patients living in distant communes compared to patients living in the same commune as the hospital (hazard ratio: 1.89, 95%CI: 1.54-2.33; P < 0.001. Hospital site, earlier year of ART start, spending less time enrolled in HIV care prior to ART initiation, receiving a non-standard ART regimen, lacking counseling prior to ART initiation, and having a higher body mass index were also associated with attrition risk. CONCLUSIONS: The findings suggest quality improvement interventions at the two hospitals, including: enhanced retention support and transportation subsidies for patients accessing care from remote areas; counseling for all patients prior to ART initiation; timely outreach to patients who miss ART pick-ups; "bridging services" for patients transferring care to alternative facilities; routine screening for anticipated interruptions in future ART pick-ups; and medical case review for patients placed on non-standard ART regimens. The findings are also relevant for policymaking on decentralization of ART services in Haiti.

  4. Observation of temperatures and emission rates from the OH and O 2 nightglow over a southern high latitude station

    Science.gov (United States)

    Chung, J.-K.; Kim, Y. H.; Won, Y.-I.; Moon, B. K.; Oh, T. H.

    2006-01-01

    A Spectral Airglow Temperature Imager (SATI) was operated at King Sejong Station (62°13'S, 58°47'W), Korea Antarctic Research Station during the period of March, 2002-September, 2003. We analyze rotational temperatures and emission rates of the O 2 (0-1) and OH (6-2) nightglows obtained at 67 nights with clear sky lasting more than 4 h. A spectral analysis of the dataset shows two dominant oscillations with periods of 4 and 6 h. The 6-h oscillations have a nearly constant phase, whereas the 4-h oscillations have nearly random phases. Although the harmonic periods of both oscillations are suggestive of tidal origin, the 4-h oscillation may have interference by other sources such as gravity waves. The 6-h oscillations could be interpreted as zonally symmetric non-migrating tides because migrating tides except high order modes have very weak amplitudes at high latitudes according to the classical tidal theory. For most cases of the observed oscillations the temperature peak leads the intensity peak, which is consistent with theoretical models for zonally symmetric tides, but contrary to other theoretical models for waves. It is needed to resolve among theoretical models whether or not zonally symmetric tide cause temperature variation prior to intensity variation in mesospheric airglows.

  5. Testing initiatives increase rates of HIV diagnosis in primary care and community settings: an observational single-centre cohort study.

    Directory of Open Access Journals (Sweden)

    Prini Mahendran

    Full Text Available The primary objective was to examine trends in new HIV diagnoses in a UK area of high HIV prevalence between 2000 and 2012 with respect to site of diagnosis and stage of HIV infection.Single-centre observational cohort study.An outpatient HIV department in a secondary care UK hospital.1359 HIV-infected adults.Demographic information (age, gender, ethnicity, and sexual orientation, site of initial HIV diagnosis (Routine settings such as HIV/GUM clinics versus Non-Routine settings such as primary care and community venues, stage of HIV infection, CD4 count and seroconversion symptoms were collated for each participant.There was a significant increase in the proportion of new HIV diagnoses made in Non-Routine settings (from 27.0% in 2000 to 58.8% in 2012; p<0.001. Overall there was a decrease in the rate of late diagnosis from 50.7% to 32.9% (p=0.001. Diagnosis of recent infection increased from 23.0% to 47.1% (p=0.001. Of those with recent infection, significantly more patients were likely to report symptoms consistent with a seroconversion illness over the 13 years (17.6% to 65.0%; p<0.001.This is the first study, we believe, to demonstrate significant improvements in HIV diagnosis and a shift in diagnosis of HIV from HIV/GUM settings to primary practice and community settings due to multiple initiatives.

  6. Lead optimization attrition analysis (LOAA): a novel and general methodology for medicinal chemistry.

    Science.gov (United States)

    Munson, Mark; Lieberman, Harvey; Tserlin, Elina; Rocnik, Jennifer; Ge, Jie; Fitzgerald, Maria; Patel, Vinod; Garcia-Echeverria, Carlos

    2015-08-01

    Herein, we report a novel and general method, lead optimization attrition analysis (LOAA), to benchmark two distinct small-molecule lead series using a relatively unbiased, simple technique and commercially available software. We illustrate this approach with data collected during lead optimization of two independent oncology programs as a case study. Easily generated graphics and attrition curves enabled us to calibrate progress and support go/no go decisions on each program. We believe that this data-driven technique could be used broadly by medicinal chemists and management to guide strategic decisions during drug discovery. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Persistence, switch rates, drug consumption and costs of biological treatment of rheumatoid arthritis: an observational study in Italy.

    Science.gov (United States)

    Degli Esposti, Luca; Favalli, Ennio Giulio; Sangiorgi, Diego; Di Turi, Roberta; Farina, Giuseppina; Gambera, Marco; Ravasio, Roberto

    2017-01-01

    The aim of this analysis was to provide an estimate of drug utilization indicators (persistence, switch rate and drug consumption) on biologics and the corresponding costs (drugs, admissions and specialist care) incurred by the Italian National Health Service in the management of adult patients with rheumatoid arthritis (RA). We conducted an observational retrospective cohort analysis using the administrative databases of three local health units. We considered all patients aged ≥18 years with a diagnosis of RA and at least one biologic drug prescription between January 2010 and December 2012 (recruitment period). Persistence was defined as maintenance over the last 3 months of the follow-up period of the same biological therapy administered at the index date. A switch was defined as the presence of a biological therapy other than that administered at the index date during the last 3 months of the follow-up period. Hospital admissions (with a diagnosis of RA or other RA-related diagnoses), specialist outpatient services, instrumental diagnostics and pharmaceutical consumption were assessed. The drug utilization analysis took into account only biologics with at least 90 patients on treatment at baseline (adalimumab n=144, etanercept n=236 and infliximab n=94). In each year, etanercept showed better persistence with initial treatment than adalimumab or infliximab. Etanercept was characterized by the lowest number of patients increasing the initial drug consumption (2.6%) and by the highest number of patients reducing the initial drug consumption (10.5%). The mean cost of treatment for a patient persisting with the initial treatment was €12,388 (€14,182 for adalimumab, €12,103 for etanercept and €11,002 for infliximab). The treatment costs for patients switching from initial treatment during the first year of follow-up were higher than for patients who did not switch (€12,710 vs. €11,332). Persistence, switch rate and drug consumption seem to directly

  8. Task shifting for cataract surgery in eastern Africa: productivity and attrition of non-physician cataract surgeons in Kenya, Malawi and Tanzania.

    Science.gov (United States)

    Eliah, Edson; Lewallen, Susan; Kalua, Khumbo; Courtright, Paul; Gichangi, Michael; Bassett, Ken

    2014-01-01

    This project examined the surgical productivity and attrition of non-physician cataract surgeons (NPCSs) in Tanzania, Malawi, and Kenya. Baseline (2008-9) data on training, support, and productivity (annual cataract surgery rate) were collected from officially trained NPCSs using mailed questionnaires followed by telephone interviews. Telephone interviews were used to collect follow-up data annually on productivity and semi-annually on attrition. A detailed telephone interview was conducted if a surgeon left his/her post. Data were entered into and analysed using STATA. Among the 135 NPCSs, 129 were enrolled in the study (Kenya 88, Tanzania 38, and Malawi 3) mean age 42 years; average time since completing training 6.6 years. Employment was in District 44%, Regional 24% or mission/ private 32% hospitals. Small incision cataract surgery was practiced by 38% of the NPCSs. The mean cataract surgery rate was 188/year, median 76 (range 0-1700). For 39 (31%) NPCSs their surgical rate was more than 200/year. Approximately 22% in Kenya and 25% in Tanzania had years where the cataract surgical rate was zero. About 11% of the surgeons had no support staff. High quality training is necessary but not sufficient to result in cataract surgical activity that meets population needs and maintains surgical skill. Needed are supporting institutions and staff, functioning equipment and programs to recruit and transport patients.

  9. Attrition in the Austrian Generations and Gender Survey: Is there a bias by fertility-relevant aspects?

    Directory of Open Access Journals (Sweden)

    Isabella Buber-Ennser

    2014-08-01

    Full Text Available Background: In longitudinal research the loss of sample members between waves is a possible source of bias. It is therefore crucial to analyse attrition. Objective: This paper analyses attrition in a longitudinal study on family and fertility, by distinguishing between attrition due to non-contact and attrition due to non-cooperation. Methods: Based on the first two waves of the Austrian Generations and Gender Survey, the two components of attrition are studied separately by using bivariate as well as multivariate methods. Moreover, overall dropout - the combination of both components - isanalysed. Apart from various socio-economic characteristics and data collection information, the study focuses on fertility-relevant variables such as fecundity, fertility intentions, sexual orientation, and traditional attitudes. Results: Fecundity, fertility intentions, and homosexual relationships are associated with higher attrition due to non-cooperation in bivariate analyses, but have no explanatory power inthe multivariate model. Pregnancy and traditional attitudes towards marriage are associated with significantly lower attrition due to non-cooperation in the multivariate context. Overall dropout is significantly lower only among persons with traditionalattitudes towards marriage, although small in size and statistical significance. Moreover, various individual and regional characteristics are significantly associated with dropout, with differences between attrition due to non-contact and attrition due to non-cooperation. Conclusions: Detailed insights into attrition are not only important when using longitudinal data and interpreting results, but also for the design of future data collections. The Austrian GGS panel has a relatively low dropout (22Š and is affected by a small bias towards familyoriented persons as well as less-educated respondents and persons with migrationbackgrounds, but the data can be used without concern about selectivity.

  10. The Effect of Downsizing on Attrition Rates in the Department of Defense (DoD)

    National Research Council Canada - National Science Library

    Broas, Tina M

    2007-01-01

    .... Downsizing has been shown to have an affect on the employees the organization retains, often termed survivors, and has been linked to increased turnover and decreased productivity and effectiveness...

  11. Federal Workforce: Attrition Rates at Ex-Im Bank and Similar Agencies

    National Research Council Canada - National Science Library

    Hess, James

    1997-01-01

    .... Financing and protection provided by Ex-Im Bank includes (1) loans to foreign buyers of U.S. exports, (2) loan guarantees to commercial lenders providing repayment protection for loans to foreign buyers...

  12. The Effect of Different Enlistment Ages on First-Term Attrition Rate

    Science.gov (United States)

    2014-03-01

    consent); no conscription; women allowed to serve in most combat roles, except the Army special forces (2013) Canada 17 years of age for voluntary male...information, such as SSN Number, date of birth, gender, race, accession date, separation date, education level, marital status, character of service (COS...23 22 Canada 17 34 23 Chile 18 45 24 Comoros 18 25 Congo, Republic of the 18 26 Croatia 18 27 62 NO COUNTRIES MIN ENLISTMENT AGE MAX

  13. Federal Workforce: Attrition Rates at Ex-Im Bank and Similar Agencies

    National Research Council Canada - National Science Library

    Hess, James

    1997-01-01

    The Ex-Im Bank's mission is to assist U.S. exporters by offering a wide range of financing at terms competitive with those of other governments' export financing agencies and absorbing risks that the private sector is reluctant to cover...

  14. Longitudinal effects of induction on teaching skills and attrition rates of beginning teacher

    NARCIS (Netherlands)

    Helms-Lorenz, Michelle; van de Grift, Wim; Maulana, Ridwan

    The teaching profession faces a shortage as well as a decline of teaching skills. A possible way to mitigate this is to implement evidence-based induction arrangements. Seventy-one schools with 338 beginning secondary education teachers were randomly allocated to an experimental or a control group.

  15. Nanocrystalline-grained tungsten prepared by surface mechanical attrition treatment: Microstructure and mechanical properties

    International Nuclear Information System (INIS)

    Guo, Hong-Yan; Xia, Min; Wu, Zheng-Tao; Chan, Lap-Chung; Dai, Yong; Wang, Kun; Yan, Qing-Zhi; He, Man-Chao; Ge, Chang-Chun; Lu, Jian

    2016-01-01

    A nanostructured surface layer was fabricated on commercial pure tungsten using the method of surface mechanical attrition treatment (SMAT). The microstructure evolution of the surface layer was characterized by using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and its formation mechanism was discussed as well. Both refinement and elongation of the brittle W grains were confirmed. The elongated SMATed W was heavily strained, the maximum value of the strain at the grain boundaries reaches as high as 3–5%. Dislocation density in the SMATed W nanograins was found to be 5 × 10 12  cm −2 . The formation of the nanograins in the top surface layer of the W was ascribed to the extremely high strain and strain rate, as well as the multidirectional repetitive loading. Bending strength of commercial W could be improved from 825 MPa to 1850 MPa by SMAT process. Microhardness results indicated the strain range in SMATed W can reach up to 220 μm beneath the top surface. The notched Charpy testing results demonstrated that SMATed W possess higher ductility than that of commercial W. The top surface of the W plates with and without SMATe processing possesses residual compressive stress of about −881 MPa and −234 MPa in y direction, and −872 MPa and −879 MPa in x direction respectively. The improvement of toughness (DBTT shift) of SMATed W may be the synergistic effect of residual compressive stress, dislocation density improvement and microstructure refinement induced by SMAT processing. SMAT processing could be a complementary method to further decrease the DBTT value of tungsten based materials.

  16. Nanocrystalline-grained tungsten prepared by surface mechanical attrition treatment: Microstructure and mechanical properties

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Hong-Yan [State Key Laboratory for GeoMechanics and Deep Underground Engineering, China University of Mining and Technology, Beijing 100083 (China); Institute of Nuclear Materials, University of Science & Technology Beijing, Beijing 100083 (China); Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Tae Chee Avenue Kowloon, Hong Kong 999077 (China); Xia, Min, E-mail: xmdsg@ustb.edu.cn [Institute of Nuclear Materials, University of Science & Technology Beijing, Beijing 100083 (China); Wu, Zheng-Tao [College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005 (China); Chan, Lap-Chung [Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Tae Chee Avenue Kowloon, Hong Kong 999077 (China); Dai, Yong; Wang, Kun [Laboratory for Nuclear Materials, Paul Scherrer Institut, 5323 Villigen PSI (Switzerland); Yan, Qing-Zhi [Institute of Nuclear Materials, University of Science & Technology Beijing, Beijing 100083 (China); He, Man-Chao [State Key Laboratory for GeoMechanics and Deep Underground Engineering, China University of Mining and Technology, Beijing 100083 (China); Ge, Chang-Chun, E-mail: ccge@mater.ustb.edu.cn [Institute of Nuclear Materials, University of Science & Technology Beijing, Beijing 100083 (China); Lu, Jian, E-mail: jianlu@cityu.edu.hk [Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Tae Chee Avenue Kowloon, Hong Kong 999077 (China)

    2016-11-15

    A nanostructured surface layer was fabricated on commercial pure tungsten using the method of surface mechanical attrition treatment (SMAT). The microstructure evolution of the surface layer was characterized by using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and its formation mechanism was discussed as well. Both refinement and elongation of the brittle W grains were confirmed. The elongated SMATed W was heavily strained, the maximum value of the strain at the grain boundaries reaches as high as 3–5%. Dislocation density in the SMATed W nanograins was found to be 5 × 10{sup 12} cm{sup −2}. The formation of the nanograins in the top surface layer of the W was ascribed to the extremely high strain and strain rate, as well as the multidirectional repetitive loading. Bending strength of commercial W could be improved from 825 MPa to 1850 MPa by SMAT process. Microhardness results indicated the strain range in SMATed W can reach up to 220 μm beneath the top surface. The notched Charpy testing results demonstrated that SMATed W possess higher ductility than that of commercial W. The top surface of the W plates with and without SMATe processing possesses residual compressive stress of about −881 MPa and −234 MPa in y direction, and −872 MPa and −879 MPa in x direction respectively. The improvement of toughness (DBTT shift) of SMATed W may be the synergistic effect of residual compressive stress, dislocation density improvement and microstructure refinement induced by SMAT processing. SMAT processing could be a complementary method to further decrease the DBTT value of tungsten based materials.

  17. An Examination of the Change in the Earth's Rotation Rate From Ancient Chinese Observations of Lunar Occultations of the Planets

    National Research Council Canada - National Science Library

    Hilton, James L; Seidelmann, P. Kenneth; Ciyuan, Liu

    1992-01-01

    ...., a period with no other known observations useful for Earth rotation studies. The observations are compared to topocentric ephemerides computed using Bretagnon's planetary theories VSOP82 and the Chapront-Touze lunar theory ELP2000-85...

  18. Personality Stability from Childhood to Midlife: Relating Teachers’ Assessments in Elementary School to Observer- and Self-Ratings 40 Years Later

    Science.gov (United States)

    Edmonds, Grant W.; Goldberg, Lewis R.; Hampson, Sarah E.; Barckley, Maureen

    2013-01-01

    We report on the longitudinal stability of personality traits across an average 40 years in the Hawaii Personality and Health Cohort relating childhood teacher assessments of personality to adult self- and observer- reports. Stabilities based on self-ratings in adulthood were compared to those measured by the Structured Interview for the Five-Factor Model (SIFFM; Trull & Widiger, 1997), and trait ratings completed by interviewers. Although convergence between self-reports and observer-ratings was modest, childhood traits demonstrated similar levels of stability across methods in adulthood. Extraversion and Conscientiousness generally showed higher stabilities, whereas Neuroticism showed none. For Agreeableness and Intellect/Openness, stability was highest when assessed with observer-ratings. These findings are discussed in terms of differences in trait evaluativeness and observability across measurement methods. PMID:24039315

  19. Career Stories of Israeli Teachers Who Left Teaching: A Salutogenic View of Teacher Attrition

    Science.gov (United States)

    Yinon, Hayuta; Orland-Barak, Lily

    2017-01-01

    Many countries experience a high percentage of teachers who leave the profession before retirement. Most of the explanations, such as teacher burnout, adopt a pathogenic point of view which perceives attrition as a negative work outcome. In contrast, the qualitative project that this article is based on, which characterizes the career…

  20. Teacher Attrition in the USA: The Relational Elements in a Utah Case Study

    Science.gov (United States)

    Newberry, Melissa; Allsop, Yvonne

    2017-01-01

    Previous work on teacher attrition in the US has indicated that those who stay in the profession and those who leave are not separate homogenous groups. In this study, the lived experience of former teachers is examined to determine the issues that distinguish leavers from stayers. The sample is from the state of Utah, a state with one of the…

  1. Pilot Testing for Feasibility in a Study of Student Retention and Attrition in Online Undergraduate Programs

    Science.gov (United States)

    Fraser, Joy; Fahlman, Dorothy; Arscott, Jane; Guillot, Isabelle

    2018-01-01

    Prior to undertaking a descriptive study on attrition and retention of students in two online undergraduate health administration and human service programs, a pilot test was conducted to assess the procedures for participant recruitment, usability of the survey questionnaire, and data collection processes. A retention model provided the…

  2. In Their Own Words: A Text Analytics Investigation of College Course Attrition

    Science.gov (United States)

    Michalski, Greg V.

    2014-01-01

    Excessive course attrition is costly to both the student and the institution. While most institutions have systems to quantify and report the numbers, far less attention is typically paid to each student's reason(s) for withdrawal. In this case study, text analytics was used to analyze a large set of open-ended written comments in which students…

  3. Analysis of Civilian Employee Attrition at the Naval Postgraduate School and Naval Support Activity - Monterey Bay

    National Research Council Canada - National Science Library

    Valverde, Xavier

    1997-01-01

    ...) and Naval Support Activity-Monterey Bay (NSA-MB) to determine what civilian non-faculty employee jobs are likely to be left vacant in the next three years due to attrition and to identify what training and skills will be needed by personnel whose...

  4. Predicting the Risk of Attrition for Undergraduate Students with Time Based Modelling

    Science.gov (United States)

    Chai, Kevin E. K.; Gibson, David

    2015-01-01

    Improving student retention is an important and challenging problem for universities. This paper reports on the development of a student attrition model for predicting which first year students are most at-risk of leaving at various points in time during their first semester of study. The objective of developing such a model is to assist…

  5. Attrition from Student Affairs: Perspectives from Those Who Exited the Profession

    Science.gov (United States)

    Marshall, Sarah M.; Gardner, Megan Moore; Hughes, Carole; Lowery, Ute

    2016-01-01

    Attrition of student affairs professionals is an issue of concern for the profession. This mixed methods study highlights reasons why participants left their student affairs careers. Seven general themes emerged from the study, including burnout, salary issues, career alternatives, work/family conflict, limited advancement, supervisor issues and…

  6. A Strategy of Attrition through Enforcement: The Unmaking of Irregular Migration in Malaysia

    OpenAIRE

    Choo Chin Low

    2017-01-01

    This article reviews Malaysia's attempt to achieve zero migration irregularity by focusing on workplace enforcement, and examines how Malaysia's migration control has become a struggle between the state and employers. Applying the framework of "enforcement through attrition", this research examines three newly introduced principles governing workplace enforcement: employer sanctions, the Strict Liability Principle, and the Employers' Mandatory Commitment. The shift to employers in Malaysia's ...

  7. The Effect of Household and Community on School Attrition: An Analysis of Thai Youth

    Science.gov (United States)

    Korinek, Kim; Punpuing, Sureeporn

    2012-01-01

    We analyze school attrition among youth in Kanchanaburi province, Thailand. We find that family investments in schooling are shaped by both household and local community contexts. There is an enrollment advantage for girls across different households and communities. We find that youth whose mothers have migrated and youth in immigrant households…

  8. An Exploration of Teacher Attrition and Mobility in High Poverty Racially Segregated Schools

    Science.gov (United States)

    Djonko-Moore, Cara M.

    2016-01-01

    The purpose of this study was to examine the mobility (movement to a new school) and attrition (quitting teaching) patterns of teachers in high poverty, racially segregated (HPRS) schools in the US. Using 2007-9 survey data from the National Center for Education Statistics, a multi-level multinomial logistic regression was performed to examine the…

  9. The Role of Social Support in First-Term Sailors’ Attrition from Recruit Training

    Science.gov (United States)

    2008-04-01

    absenteeism , and job turnover during the first year of employment. Academy of Management Journal, 28, 88-109. Shils, E. A. & Janowitz, M. (1948). Cohesion and...British Army. Journal of Organizational Behavior, 19, 745-767. Tinto, V. (1993). Leaving college: Rethinking the causes and cures of student attrition

  10. Disappearing Act: Persistence and Attrition of Uniform Resource Locators (URLs) in an Open Access Medical Journal

    Science.gov (United States)

    Nagaraja, Aragudige; Joseph, Shine A.; Polen, Hyla H.; Clauson, Kevin A.

    2011-01-01

    Purpose: The aim of this paper is to assess and catalogue the magnitude of URL attrition in a high-impact, open access (OA) general medical journal. Design/methodology/approach: All "Public Library of Science Medicine (PLoS Medicine)" articles for 2005-2007 were evaluated and the following items were assessed: number of entries per issue; type of…

  11. ART attrition and risk factors among Option B+ patients in Haiti: A retrospective cohort study.

    Directory of Open Access Journals (Sweden)

    Nancy Puttkammer

    Full Text Available In October 2012, the Haitian Ministry of Health endorsed the "Option B+" strategy to eliminate mother-to-child transmission of HIV and achieve HIV epidemic control. The objective of this paper is to assess and identify risk factors for attrition from the national ART program among Option B+ patients in the 12 months after ART initiation.This retrospective cohort study included patients newly initiating ART from October 2012-August 2013 at 68 ART sites covering 45% of all newly enrolled ART patients in all regions of Haiti.With data from electronic medical records, we carried out descriptive analysis of sociodemographic, clinical, and pregnancy-related correlates of ART attrition, and used a modified Poisson regression approach to estimate relative risks in a multivariable model.There were 2,166 Option B+ patients who initiated ART, of whom 1,023 were not retained by 12 months (47.2%. One quarter (25.3% dropped out within 3 months of ART initiation. Protective factors included older age, more advanced HIV disease progression, and any adherence counseling prior to ART initiation, while risk factors included starting ART late in gestation, starting ART within 7 days of HIV testing, and using an atypical ART regimen.Our study demonstrates early ART attrition among Option B+ patients and contributes evidence on the characteristics of women who are most at risk of attrition in Haiti. Our findings highlight the importance of targeted strategies to support retention among Option B+ patients.

  12. Attrition in Chronic Disease Self-Management Programs and Self-Efficacy at Enrollment

    Science.gov (United States)

    Verevkina, Nina; Shi, Yunfeng; Fuentes-Caceres, Veronica Alejandra; Scanlon, Dennis Patrick

    2014-01-01

    Among other goals, the Chronic Disease Self-Management Program (CDSMP) is designed to improve self-efficacy of the chronically ill. However, a substantial proportion of the enrollees often leave CDSMPs before completing the program curriculum. This study examines factors associated with program attrition in a CDSMP implemented in a community…

  13. Minimising Attrition: Strategies for Assisting Students Who Are at Risk of Withdrawal

    Science.gov (United States)

    Park, Caroline L.; Perry, Beth; Edwards, Margaret

    2011-01-01

    This paper explores strategies aimed at minimising attrition by encouraging persistence among online graduate students who are considering withdrawal. It builds upon earlier studies conducted by a team of researchers who teach online graduate students in health care at Athabasca University. First, in 2008-2009, Park, Boman, Care, Edwards, and…

  14. Patterns of Student Enrolment and Attrition in Australian Open Access Online Education: A Preliminary Case Study

    Science.gov (United States)

    Greenland, Steven J.; Moore, Catherine

    2014-01-01

    Swinburne University of Technology has experienced tremendous growth in open access online learning and as such is typical of the many Australian institutions that have ventured into online tertiary education. While research in online education continues to expand, comparatively little investigates students' enrolment and attrition. This research…

  15. Journey to Becoming a Thai English Teacher: New Perspective on Investigating Teacher Attrition

    Science.gov (United States)

    Prabjandee, Denchai

    2014-01-01

    In this study, the author provides a unique perspective on teacher shortage by focusing on teacher retention, in terms of why teachers stay in the teaching profession, rather than focusing on teacher attrition, or why teachers leave the teaching profession. The change in perspective created an opportunity to study the journey of how teachers chose…

  16. Persistence, switch rates, drug consumption and costs of biological treatment of rheumatoid arthritis: an observational study in Italy

    Directory of Open Access Journals (Sweden)

    Degli Esposti L

    2016-12-01

    Full Text Available Luca Degli Esposti,1 Ennio Giulio Favalli,2 Diego Sangiorgi,1 Roberta Di Turi,3 Giuseppina Farina,4 Marco Gambera,5 Roberto Ravasio,6 1CliCon S.r.l. – Health, Economics & Outcomes Research, Ravenna, 2Department of Rheumatology, Istituto Ortopedico Gaetano Pini, Milan, 3Local Pharmaceutical and Supplementary Assistance Unit, Roma Local Health Authority D, Rome, 4Internal Management Control Unit – Pharmaceutical Spending Control Sector, Caserta Local Health Authority, Caserta, 5Local Pharmaceutical Service, Bergamo Local Health Authority, Bergamo, 6Health Publishing & Services Srl, Milan, Italy Objectives: The aim of this analysis was to provide an estimate of drug utilization indicators (persistence, switch rate and drug consumption on biologics and the corresponding costs (drugs, admissions and specialist care incurred by the Italian National Health Service in the management of adult patients with rheumatoid arthritis (RA.Methods: We conducted an observational retrospective cohort analysis using the administrative databases of three local health units. We considered all patients aged ≥18 years with a diagnosis of RA and at least one biologic drug prescription between January 2010 and December 2012 (recruitment period. Persistence was defined as maintenance over the last 3 months of the follow-up period of the same biological therapy administered at the index date. A switch was defined as the presence of a biological therapy other than that administered at the index date during the last 3 months of the follow-up period. Hospital admissions (with a diagnosis of RA or other RA-related diagnoses, specialist outpatient services, instrumental diagnostics and pharmaceutical consumption were assessed.Results: The drug utilization analysis took into account only biologics with at least 90 patients on treatment at baseline (adalimumab n=144, etanercept n=236 and infliximab n=94. In each year, etanercept showed better persistence with initial

  17. Planned home compared with planned hospital births: Mode of delivery and Perinatal mortality rates, an observational study

    NARCIS (Netherlands)

    Kooy, J. (Jacoba); E. Birnie (Erwin); S. Denktaş (Semiha); E.A.P. Steegers (Eric); G.J. Bonsel (Gouke)

    2017-01-01

    textabstractBackground: To compare the mode of delivery between planned home versus planned hospital births and to determine if differences in intervention rates could be interpreted as over- or undertreatment. Methods: Intervention and perinatal mortality rates were obtained for 679,952 low-risk

  18. SUPPLEMENT: "THE RATE OF BINARY BLACK HOLE MERGERS INFERRED FROM ADVANCED LIGO OBSERVATIONS SURROUNDING GW150914" (2016, ApJL, 833, L1)

    NARCIS (Netherlands)

    Abbott, B. P.; Abbott, R.; Abbott, T. D.; Abernathy, M. R.; Acernese, F.; Ackley, K.; Adams, C.; Phythian-Adams, A.T.; Addesso, P.; Adhikari, R. X.; Adya, V. B.; Affeldt, C.; Agathos, M.; Agatsuma, K.; Aggarwal, N.T.; Aguiar, O. D.; Aiello, L.; Ain, A.; Ajith, P.; Allen, B.; Allocca, A.; Altin, P. A.; Anderson, S. B.; Anderson, W. G.; Arai, K.; Araya, M. C.; Arceneaux, C. C.; Areeda, J. S.; Arnaud, N.; Arun, K. G.; Ascenzi, S.; Ashton, G.; Ast, M.; Aston, S. M.; Astone, P.; Aufmuth, P.; Aulbert, C.; Babak, S.; Bacon, P.; Bader, M. K. M.; Baker, P. T.; Baldaccini, F.; Ballardin, G.; Ballmer, S. W.; Barayoga, J. C.; Barclay, S. E.; Barish, B. C.; Barker, R.D.; Barone, F.; Barr, B.; Barsotti, L.; Barsuglia, M.; Barta, D.; Bartlett, J.; Bartos, I.; Bassiri, R.; Basti, A.; Batch, J. C.; Baune, C.; Bavigadda, V.; Bazzan, M.; Behnke, B.; Bejger, M.; Bell, A. S.; Bell, C. J.; Berger, B. K.; Bergman, J.; Bergmann, G.; Berry, C. P. L.; Bersanetti, D.; Bertolini, A.; Betzwieser, J.; Bhagwat, S.; Bhandare, R.; Bilenko, I. A.; Billingsley, G.; Birch, M.J.; Birney, R.; Biscans, S.; Bisht, A.; Bitossi, M.; Biwer, C.; Bizouard, M. A.; Blackburn, J. K.; Blair, C. D.; Blair, D. G.; Blair, R. M.; Bloemen, A.L.S.; Bock, O.; Bodiya, T. P.; Boer, M.; Bogaert, J.G.; Bogan, C.; Bohe, A.; Bojtos, P.; Bond, T.C; Bondu, F.; Bonnand, R.; Boom, B. A.; Bork, R.; Boschi, V.; Bose, S.; Bouffanais, Y.; Bozzi, A.; Bradaschia, C.; Brady, P. R.; Braginsky, V. B.; Branchesi, M.; Brau, J. E.; Briant, T.; Brillet, A.; Brinkmann, M.; Brisson, V.; Brockill, P.; Brooks, A. F.; Brown, A.D.; Brown, D.; Brown, N. M.; Buchanan, C. C.; Buikema, A.; Bulik, T.; Bulten, H. J.; Buonanno, A.; Buskulic, D.; Buy, C.; Byer, R. L.; Cadonati, L.; Cagnoli, G.; Cahillane, C.; Calderon Bustillo, J.; Callister, T. A.; Calloni, E.; Camp, J. B.; Cannon, K. C.; Cao, J.; Capano, C. D.; Capocasa, E.; Carbognani, F.; Caride, S.; Diaz, J. Casanueva; Casentini, C.; Caudill, S.; Cavaglia, M.; Cavalier, F.; Cavalieri, R.; Cella, G.; Cepeda, C. B.; Baiardi, L. Cerboni; Cerretani, G.; Cesarini, E.; Chakraborty, R.; Chalermsongsak, T.; Chamberlin, S. J.; Chan, M.; Chao, D. S.; Charlton, P.; Chassande-Mottin, E.; Chen, H. Y.; Chen, Y; Cheng, C.; Chincarini, A.; Chiummo, A.; Cho, H. S.; Cho, M.; Chow, J. H.; Christensen, N.; Chu, Qian; Chua, S. E.; Chung, E.S.; Ciani, G.; Clara, F.; Clark, J. A.; Cleva, F.; Coccia, E.; Cohadon, P. -F.; Colla, A.; Collette, C. G.; Cominsky, L.; Constancio, M., Jr.; Conte, A.; Conti, L.; Cook, D.; Corbitt, T. R.; Cornish, N.; Corsi, A.; Cortese, S.; Costa, A.C.; Coughlin, M. W.; Coughlin, S. B.; Coulon, J. -P.; Countryman, S. T.; Couvares, P.; Cowan, E. E.; Coward, D. M.; Cowart, M. J.; Coyne, D. C.; Coyne, R.; Craig, K.; Creighton, J. D. E.; Cripe, J.; Crowder, S. G.; Cumming, A.; Cunningham, A.L.; Cuoco, E.; Dal Canton, T.; Danilishin, S. L.; D'Antonio, S.; Danzmann, K.; Darman, N. S.; Dattilo, V.; Dave, I.; Daveloza, H. P.; Davier, M.; Davies, G. S.; Daw, E. J.; Day, R.; De, S.; Debra, D.; Debreczeni, G.; Degallaix, J.; De laurentis, M.; Deleglise, S.; Del Pozzo, W.; Denker, T.; Dent, T.; Dereli, H.; Dergachev, V.A.; Rosa, R.; DeRosa, R. T.; DeSalvo, R.; Dhurandhar, S.; Diaz, M. C.; Di Fiore, L.; Giovanni, M.G.; Di Lieto, A.; Di Pace, S.; Di Palma, I.; Di Virgilio, A.; Dojcinoski, G.; Dolique, V.; Donovan, F.; Dooley, K. L.; Doravari, S.; Douglas, R.; Downes, T. P.; Drago, M.; Drever, R. W. P.; Driggers, J. C.; Du, Z.; Ducrot, M.; Dwyer, S. E.; Edo, T. B.; Edwards, M. C.; Effler, A.; Eggenstein, H. -B.; Ehrens, P.; Eichholz, J.; Eikenberry, S. S.; Engels, W.; Essick, R. C.; Etzel, T.; Evans, T. M.; Evans, T. M.; Everett, R.; Factourovich, M.; Fafone, V.; Fair, H.; Fairhurst, S.; Fan, X.M.; Fang, Q.; Farinon, S.; Farr, B.; Farr, W. M.; Favata, M.; Fays, M.; Fehrmann, H.; Fejer, M. M.; Ferrante, I.; Ferreira, E. C.; Ferrini, F.; Fidecaro, F.; Fiori, I.; Fiorucci, D.; Fisher, R. P.; Flaminio, R.; Fletcher, M; Fong, H.; Fournier, J. -D.; Franco, S; Frasca, S.; Frasconi, F.; Frei, Z.; Freise, A.; Frey, R.; Frey, V.; Fricke, T. T.; Fritschel, P.; Frolov, V. V.; Fulda, P.; Fyffe, M.; Gabbard, H. A. G.; Gair, J. R.; Gammaitoni, L.; Gaonkar, S. G.; Garufi, F.; Gatto, A.; Gaur, G.; Gehrels, N.; Gemme, G.; Gendre, B.; Genin, E.; Gennai, A.; George, J.; Gergely, L.; Germain, V.; Ghosh, Archisman; Ghosh, S.; Giaime, J. A.; Giardina, K. D.; Giazotto, A.; Gill, K.P.; Glaefke, A.; Goetz, E.; Goetz, R.; Gondan, L.; Gonzalez, R.G.; Castro, J. M. Gonzalez; Gopakumar, A.; Gordon, A; Gorodetsky, M. L.; Gossan, S. E.; Lee-Gosselin, M.; Gouaty, R.; Graef, C.; Graff, P. B.; Granata, M.; Grant, A.; Gras, S.; Gray, C.M.; Greco, G.; Green, A. C.; Groot, P.; Grote, H.; Grunewald, S.; Guidi, G. M.; Guo, X.; Gupta, A.; Gupta, M. K.; Gushwa, K. E.; Gustafson, E. K.; Gustafson, R.; Hacker, J. J.; Buffoni-Hall, R.; Hall, E. D.; Hammond, G.L.; Haney, M.; Hanke, M. M.; Hanks, J.; Hanna, C.; Hannam, M. D.; Hanson, P.J.; Hardwick, T.; Harms, J.; Harry, G. M.; Harry, I. W.; Hart, M. J.; Hartman, M. T.; Haster, C. -J.; Haughian, K.; Heidmann, A.; Heintze, M. C.; Heitmann, H.; Hello, P.; Hemming, G.; Hendry, M.; Heng, I. S.; Hennig, J.; Heptonstall, A. W.; Heurs, M.; Hild, S.; Hoak, D.; Hodge, K. A.; Hofman, D.; Hollitt, S. E.; Holt, K.; Holz, D. E.; Hopkins, P.; Hosken, D. J.; Hough, J.; Houston, E. A.; Howell, E. J.; Hu, Y. M.; Huang, S.; Huerta, E. A.; Huet, D.; Hughey, B.; Husa, S.; Huttner, S. H.; Huynh-Dinh, T.; Idrisy, A.; Indik, N.; Ingram, D. R.; Inta, R.; Isa, H. N.; Isac, J. -M.; Isi, M.; Islas, G.; Isogai, T.; Iyer, B. R.; Izumi, K.; Jacqmin, T.; Jang, D.H.; Jani, K.; Jaranowski, P.; Jawahar, S.; Jimenez-Forteza, F.; Johnson, W.; Jones, I.D.; Jones, R.; Jonker, R. J. G.; Ju, L.; Haris, K.; Kalaghatgi, C. V.; Kalogera, V.; Kandhasamy, S.; Kang, G.H.; Kanner, J. B.; Karki, S.; Kasprzack, M.; Katsavounidis, E.; Katzman, W.; Kaufer, S.; Kaur, T.; Kawabe, K.; Kawazoe, F.; Kefelian, F.; Kehl, M. S.; Keitel, D.; Kelley, D. B.; Kells, W.; Kennedy, R.E.; Key, J. S.; Khalaidovski, A.; Khalili, F. Y.; Khan, I.; Khan., S.; Khan, Z.; Khazanov, E. A.; Kijbunchoo, N.; Kim, C.; Kim, J.; Kim, K.; Kim, Nam-Gyu; Kim, Namjun; Kim, Y.M.; King, E. J.; King, P. J.; Kinzel, D. L.; Kissel, J. S.; Kleybolte, L.; Klimenko, S.; Koehlenbeck, S. M.; Kokeyama, K.; Koley, S.; Kondrashov, V.; Kontos, A.; Korobko, M.; Korth, W. Z.; Kowalska, I.; Kozak, D. B.; Kringel, V.; Krishnan, B.; Krolak, A.; Krueger, C.; Kuehn, G.; Kumar, P.; Kuo, L.; Kutynia, A.; Lackey, B. D.; Landry, M.; Lange, J.; Lantz, B.; Lasky, P. D.; Lazzarini, A.; Lazzaro, C.; Leaci, P.; Leavey, S.; Lebigot, E. O.; Lee, C.H.; Lee, K.H.; Lee, M.H.; Lee, K.; Lenon, A.; Leonardi, M.; Leong, J. R.; Leroy, N.; Letendre, N.; Levin, Y.; Levine, B. M.; Li, T. G. F.; Libson, A.; Littenberg, T. B.; Lockerbie, N. A.; Logue, J.; Lombardi, A. L.; Lord, J. E.; Lorenzini, M.; Loriette, V.; Lormand, M.; Losurdo, G.; Lough, J. D.; Lueck, H.; Lundgren, A. P.; Luo, J.; Lynch, R.; Ma, Y.; MacDonald, T.T.; Machenschalk, B.; MacInnis, M.; Macleod, D. M.; Magana-Sandoval, F.; Magee, R. M.; Mageswaran, M.; Majorana, E.; Maksimovic, I.; Malvezzi, V.; Man, N.; Mandel, I.; Mandic, V.; Mangano, V.; Mansell, G. L.; Manske, M.; Mantovani, M.; Marchesoni, F.; Marion, F.; Marka, S.; Marka, Z.; Markosyan, A. S.; Maros, E.; Martelli, F.; Martellini, L.; Martin, I. W.; Martin, R.M.; Martynov, D. V.; Marx, J. N.; Mason, K.; Masserot, A.; Massinger, T. J.; Masso-Reid, M.; Matichard, F.; Matone, L.; Mavalvala, N.; Mazumder, N.; Mazzolo, G.; McCarthy, R.; McClelland, D. E.; McCormick, S.; McGuire, S. C.; McIntyre, G.; McIver, J.; McManus, D. J.; McWilliams, S. T.; Meacher, D.; Meadors, G. D.; Meidam, J.; Melatos, A.; Mendell, G.; Mendoza-Gandara, D.; Mercer, R. A.; Merilh, E. L.; Merzougui, M.; Meshkov, S.; Messenger, C.; Messick, C.; Meyers, P. M.; Mezzani, F.; Miao, H.; Michel, C.; Middleton, H.; Mikhailov, E. E.; Milano, L.; Miller, J.; Millhouse, M.; Minenkov, Y.; Ming, J.; Mirshekari, S.; Mishra, C.; Mitra, S.; Mitrofanov, V. P.; Mitselmakher, G.; Mittleman, R.; Moggi, A.; Mohan, M.; Mohapatra, S. R. P.; Montani, M.; Moore, B.C.; Moore, J.C.; Moraru, D.; Gutierrez Moreno, M.; Morriss, S. R.; Mossavi, K.; Mours, B.; Mow-Lowry, C. M.; Mueller, C. L.; Mueller, G.; Muir, A. W.; Mukherjee, Arunava; Mukherjee, S.D.; Mukherjee, S.; Mukund, N.; Mullavey, A.; Munch, J.; Murphy, D. J.; Murray, P.G.; Mytidis, A.; Nardecchia, I.; Naticchioni, L.; Nayak, R. K.; Necula, V.; Nedkova, K.; Nelemans, G.; Gutierrez-Neri, M.; Neunzert, A.; Newton-Howes, G.; Nguyen, T. T.; Nielsen, A. B.; Nissanke, S.; Nitz, A.; Nocera, F.; Nolting, D.; Normandin, M. E. N.; Nuttall, L. K.; Oberling, J.; Ochsner, E.; O'Dell, J.; Oelker, E.; Ogin, G. H.; Oh, J.; Oh, S. H.; Ohme, F.; Oliver, M. B.; Oppermann, P.; Oram, Richard J.; O'Reilly, B.; O'Shaughnessy, R.; Ottaway, D. J.; Ottens, R. S.; Overmier, H.; Owen, B. J.; Pai, A.; Pai, S. A.; Palamos, J. R.; Palashov, O.; Palomba, C.; Pal-Singh, A.; Pan, H.; Pankow, C.; Pannarale, F.; Pant, B. C.; Paoletti, F.; Paoli, A.; Papa, M. A.; Paris, H. R.; Parker, W.S; Pascucci, D.; Pasqualetti, A.; Passaquieti, R.; Passuello, D.; Patricelli, B.; Patrick, Z.; Pearlstone, B. L.; Pedraza, M.; Pedurand, R.; Pekowsky, L.; Pele, A.; Penn, S.; Perreca, A.; Phelps, M.; Piccinni, O. J.; Pichot, M.; Piergiovanni, F.; Pierro, V.; Pillant, G.; Pinard, L.; Pinto, I. M.; Pitkin, M.; Poggiani, R.; Popolizio, P.; Porter, E. K.; Post, A.; Powell, J.; Prasad, J.; Predoi, V.; Premachandra, S. S.; Prestegard, T.; Price, L. R.; Prijatelj, M.; Principe, M.; Privitera, S.; Prodi, G. A.; Prokhorov, L. G.; Puncken, O.; Punturo, M.; Puppo, P.; Puerrer, M.; Qi, H.; Qin, J.; Quetschke, V.; Quintero, E. A.; Quitzow-James, R.; Raab, F. J.; Rabeling, D. S.; Radkins, H.; Raffai, P.; Raja, S.; Rakhmanov, M.; Rapagnani, P.; Raymond, V.; Razzano, M.; Re, V.; Read, J.; Reed, C. M.; Regimbau, T.; Rei, L.; Reid, S.; Reitze, D. H.; Rew, H.; Reyes, S. D.; Ricci, F.; Riles, K.; Robertson, N. A.; Robie, R.; Robinet, F.; Rocchi, A.; Rolland, L.; Rollins, J. G.; Roma, V. J.; Romano, R.; Romanov, G.; Romie, J. H.; Rosinska, D.; Rowan, S.; Ruediger, A.; Ruggi, P.; Ryan, K.A.; Sachdev, P.S.; Sadecki, T.; Sadeghian, L.; Salconi, L.; Saleem, M.; Salemi, F.; Samajdar, A.; Sammut, L.; Sampson, L. M.; Sanchez, E. J.; Sandberg, V.; Sandeen, B.; Sanders, J. R.; Sassolas, B.; Sathyaprakash, B. S.; Saulson, P. R.; Sauter, O.; Savage, R. L.; Sawadsky, A.; Schale, P.; Schilling, R.; Schmidt, J; Schmidt, P.; Schnabel, R.B.; Schofield, R. M. S.; Schoenbeck, A.; Schreiber, K.E.C.; Schuette, D.; Schutz, B. F.; Scott, J.; Scott, M.S.; Sellers, D.; Sengupta, A. S.; Sentenac, D.; Sequino, V.; Sergeev, A.; Serna, G.; Setyawati, Y.; Sevigny, A.; Shaddock, D. A.; Shah, S.; Shahriar, M. S.; Shaltev, M.; Shao, Z.M.; Shapiro, B.; Shawhan, P.; Sheperd, A.; Shoemaker, D. H.; Shoemaker, D. M.; Siellez, K.; Siemens, X.; Sigg, D.; Silva, António Dias da; Simakov, D.; Singer, A; Singer, L. P.; Singh, A.; Singh, R.; Singhal, A.; Sintes, A. M.; Slagmolen, B. J. J.; Smith, R. J. E.; Smith, N.D.; Smith, R. J. E.; Son, E. J.; Sorazu, B.; Sorrentino, F.; Souradeep, T.; Srivastava, A. K.; Staley, A.; Steinke, M.; Steinlechner, J.; Steinlechner, S.; Steinmeyer, D.; Stephens, B. C.; Stevenson-Moore, P.; Stone, J.R.; Strain, K. A.; Straniero, N.; Stratta, G.; Strauss, N. A.; Strigin, S. E.; Sturani, R.; Stuver, A. L.; Summerscales, T. Z.; Sun, L.; Sutton, P. J.; Swinkels, B. L.; Szczepanczyk, M. J.; Tacca, M.D.; Talukder, D.; Tanner, D. B.; Tapai, M.; Tarabrin, S. P.; Taracchini, A.; Taylor, W.R.; Theeg, T.; Thirugnanasambandam, M. P.; Thomas, E. G.; Thomas, M.; Thomas, P.; Thorne, K. A.; Thorne, K. S.; Thrane, E.; Tiwari, S.; Tiwari, V.; Tokmakov, K. V.; Tomlinson, C.; Tonelli, M.; Torres, C. V.; Torrie, C. I.; Toyra, D.; Travasso, F.; Traylor, G.; Trifiro, D.; Tringali, M. C.; Trozzo, L.; Tse, M.; Turconi, M.; Tuyenbayev, D.; Ugolini, D.; Unnikrishnan, C. S.; Urban, A. L.; Usman, S. A.; Vahlbruch, H.; Vajente, G.; Valdes, G.; Vallisneri, M.; van Bakel, N.; van Beuzekom, M.G.; van den Brand, J. F. J.; Van Den Broeck, C.F.F.; Vander-Hyde, D. C.; van der Schaaf, L.; van Heijningen, J. V.; van Veggel, A. A.; Vardaro, M.; Vass, S.; Vasuth, M.; Vaulin, R.; Vecchio, A.; Vedovato, G.; Veitch, J.; Veitch, P.J.; Venkateswara, K.; Verkindt, D.; Vetrano, F.; Vicere, A.; Vinciguerra, S.; Vine, D. J.; Vinet, J. -Y.; Vitale, S.; Vo, T.; Vocca, H.; Vorvick, C.; Voss, D. V.; Vousden, W. D.; Vyatchanin, S. P.; Wade, A. R.; Wade, L. E.; Wade, MT; Walker, M.; Wallace, L.; Walsh, S.; Wang, G.; Wang, H.; Wang, M.; Wang, X.; Wang, Y.; Ward, R. L.; Warner, J.; Was, M.; Weaver, B.; Wei, L. -W.; Weinert, M.; Weinstein, A. J.; Weiss, R.; Welborn, T.; Wen, L.M.; Wesels, P.; Westphal, T.; Wette, K.; Whelan, J. T.; White, D. J.; Whiting, B. F.; Williams, D.R.; Williamson, A. R.; Willis, J. L.; Willke, B.; Wimmer, M. H.; Winkler, W.; Wipf, C. C.; Wittel, H.; Woan, G.; Worden, J.; Wright, J.L.; Wu, G.; Yablon, J.; Yam, W.; Yamamoto, H.; Yancey, C. C.; Yap, M. J.; Yu, H.; Yvert, M.; Zadrozny, A.; Zangrando, L.; Zanolin, M.; Zendri, J. -P.; Zevin, M.; Zhang, F.; Zhang, L.; Zhang, M.; Zhang, Y.; Zhao, C.; Zhou, M.; Zhou, Z.; Zhu, X. J.; Zucker, M. E.; Zuraw, S. E.

    2016-01-01

    This article provides supplemental information for a Letter reporting the rate of (BBH) coalescences inferred from 16 days of coincident Advanced LIGO observations surrounding the transient (GW) signal GW150914. In that work we reported various rate estimates whose 90% confidence intervals fell in

  19. Predictors of attrition with buprenorphine/naloxone treatment in opioid dependent youth☆

    Science.gov (United States)

    Warden, Diane; Subramaniam, Geetha A.; Carmody, Thomas; Woody, George E.; Minhajuddin, Abu; Poole, Sabrina A.; Potter, Jennifer; Fishman, Marc; Bogenschutz, Michael; Patkar, Ashwin; Trivedi, Madhukar H.

    2012-01-01

    Background In opioid dependent youth there is substantial attrition from medication-assisted treatment. If youth at risk for attrition can be identified at treatment entry or early in treatment, they can be targeted for interventions to help retain them in treatment. Methods Opioid dependent adolescents and young adults (n=152), aged 15–21, were randomized to 12 weeks (BUP, n=74) or 2 weeks of detoxification (DETOX, n=78) with buprenorphine/naloxone (Bup/Nal), both in combination with 12 weeks of psychosocial treatment. Baseline and early treatment related predictors of treatment attrition were identified in each group using bivariate and multivariate logistic regression. Results In the DETOX group 36% left between weeks 2 and 4, at the end of the dose taper, while in the BUP group only 8% left by week 4. In the BUP group, early adherence to Bup/Nal, early opioid negative urines, use of any medications in the month prior to treatment entry, and lifetime non-heroin opioid use were associated with retention while prior 30-day hallucinogen use was associated with attrition. In the DETOX group, only use of sleep medications was associated with retention although not an independent predictor. A broad range of other pre-treatment characteristics was unrelated to attrition. Conclusions Prompt attention to those with early non-adherence to medication or an early opioid positive urine, markers available in the first 2 weeks of treatment, may improve treatment retention. Extended Bup/ Nal treatment appeared effective in improving treatment retention for youth with opioid dependence across a wide range of demographics, and pre-treatment clinical characteristics. PMID:22626890

  20. Predictors of attrition with buprenorphine/naloxone treatment in opioid dependent youth.

    Science.gov (United States)

    Warden, Diane; Subramaniam, Geetha A; Carmody, Thomas; Woody, George E; Minhajuddin, Abu; Poole, Sabrina A; Potter, Jennifer; Fishman, Marc; Bogenschutz, Michael; Patkar, Ashwin; Trivedi, Madhukar H

    2012-09-01

    In opioid dependent youth there is substantial attrition from medication-assisted treatment. If youth at risk for attrition can be identified at treatment entry or early in treatment, they can be targeted for interventions to help retain them in treatment. Opioid dependent adolescents and young adults (n=152), aged 15-21, were randomized to 12 weeks (BUP, n=74) or 2 weeks of detoxification (DETOX, n=78) with buprenorphine/naloxone (Bup/Nal), both in combination with 12 weeks of psychosocial treatment. Baseline and early treatment related predictors of treatment attrition were identified in each group using bivariate and multivariate logistic regression. In the DETOX group 36% left between weeks 2 and 4, at the end of the dose taper, while in the BUP group only 8% left by week 4. In the BUP group, early adherence to Bup/Nal, early opioid negative urines, use of any medications in the month prior to treatment entry, and lifetime non-heroin opioid use were associated with retention while prior 30-day hallucinogen use was associated with attrition. In the DETOX group, only use of sleep medications was associated with retention although not an independent predictor. A broad range of other pre-treatment characteristics was unrelated to attrition. Prompt attention to those with early non-adherence to medication or an early opioid positive urine, markers available in the first 2 weeks of treatment, may improve treatment retention. Extended Bup/Nal treatment appeared effective in improving treatment retention for youth with opioid dependence across a wide range of demographics, and pre-treatment clinical characteristics. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Factors affecting the attrition of community-directed distributors of ivermectin, in an onchocerciasis-control programme in the Imo and Abia states of south-eastern Nigeria.

    Science.gov (United States)

    Emukah, E C; Enyinnaya, U; Olaniran, N S; Akpan, E A; Hopkins, D R; Miri, E S; Amazigo, U; Okoronkwo, C; Stanley, A; Rakers, L; Richards, F O; Katabarwa, M N

    2008-01-01

    In areas of Nigeria where onchocerciasis is endemic, community-directed distributors (CDD) distribute ivermectin annually, as part of the effort to control the disease. Unfortunately, it has been reported that at least 35% of the distributors who have been trained in Nigeria are unwilling to participate further as CDD. The selection and training of new CDD, to replace those unwilling to continue, leads to annual expense that the national onchocerciasis-programme is finding difficult to meet, given other programme priorities and the limited resources. If the reported levels of attrition are true, they seriously threaten the sustainability of community-directed treatment with ivermectin (CDTI) in Nigeria. In 2002, interviews were held with 101 people who had been trained as CDD, including those who had stopped serving their communities, from 12 communities in south-eastern Nigeria that had high rates of CDD attrition. The results showed that, although the overall reported CDD attrition was 40.6%, the actual rate was only 10.9%. The CDD who had ceased participating in the annual rounds of ivermectin blamed a lack of incentives (65.9%), the demands of other employment (14.6%), the long distances involved in the house-to-house distribution (12.2%) or marital duties (7.3%). Analysis of the data obtained from all the interviewed CDD showed that inadequate supplies of ivermectin (P<0.01), lack of supervision (P<0.05) and a lack of monetary incentives (P<0.001) led to significant increases in attrition. Conversely, CDD retention was significantly enhanced when the distributors were selected by their community members (P<0.001), supervised (P<0.001), supplied with adequate ivermectin tablets (P<0.05), involved in educating their community members (P<0.05), and/or involved in other health programmes (P<0.001). Although CDD who were involved in other health programmes were relatively unlikely to cease participating in the distributions, they were more likely to take longer

  2. Patient retention, clinical outcomes and attrition-associated factors of HIV-infected patients enrolled in Zimbabwe's National Antiretroviral Therapy Programme, 2007-2010.

    Directory of Open Access Journals (Sweden)

    Tsitsi Mutasa-Apollo

    Full Text Available Since establishment of Zimbabwe's National Antiretroviral Therapy (ART Programme in 2004, ART provision has expanded from <5,000 to 369,431 adults by 2011. However, patient outcomes are unexplored.To determine improvement in health status, retention and factors associated with attrition among HIV-infected patients on ART.A retrospective review of abstracted patient records of adults ≥ 15 years who initiated ART from 2007 to 2009 was done. Frequencies and medians were calculated for rates of retention in care and changes in key health status outcomes at 6, 12, 24 and 36 months respectively. Cox proportional hazards models were used to determine factors associated with attrition.Of the 3,919 patients, 64% were female, 86% were either WHO clinical stage III or IV. Rates of patient retention at 6, 12, 24 and 36 months were 90.7%, 78.1%, 68.8% and 64.4%, respectively. After ART initiation, median weight gains at 6, 12, and 24 months were 3, 4.5, and 5.0 kgs whilst median CD4+ cell count gains at 6, 12 and 24 months were 122, 157 and 279 cells/µL respectively. Factors associated with an increased risk of attrition included male gender (AHR 1.2; 95% CI, 1.1-1.4, baseline WHO stage IV (AHR 1.7; 95% CI, 1.1-2.6, lower baseline body weight (AHR 2.0; 95% CI, 1.4-2. 8 and accessing care from higher level healthcare facilities (AHR 3.5; 95% 1.1-11.2.Our findings with regard to retention as well as clinical and immunological improvements following uptake of ART, are similar to what has been found in other settings. Factors influencing attrition also mirror those found in other parts of sub-Saharan Africa. These findings suggest the need to strengthen earlier diagnosis and treatment to further improve treatment outcomes. Whilst decentralisation improves ART coverage it should be coupled with strategies aimed at improving patient retention.

  3. Family Income, Parent Education, and Perceived Constraints as Predictors of Observed Program Quality and Parent Rated Program Quality

    Science.gov (United States)

    Torquati, Julia C.; Raikes, Helen H.; Huddleston-Casas, Catherine A.; Bovaird, James A.; Harris, Beatrice A.

    2011-01-01

    Observed child care quality and parent perceptions of child care quality received by children in poor (below Federal Poverty Line, FPL), low-income (between FPL and 200% of FPL), and non-low-income families were examined. Observations were completed in 359 center- and home-based child care programs in four Midwestern states and surveys were…

  4. An intervention to improve the catheter associated urinary tract infection rate in a medical intensive care unit: Direct observation of catheter insertion procedure.

    Science.gov (United States)

    Galiczewski, Janet M; Shurpin, Kathleen M

    2017-06-01

    Healthcare associated infections from indwelling urinary catheters lead to increased patient morbidity and mortality. The purpose of this study was to determine if direct observation of the urinary catheter insertion procedure, as compared to the standard process, decreased catheter utilization and urinary tract infection rates. This case control study was conducted in a medical intensive care unit. During phase I, a retrospective data review was conducted on utilsiation and urinary catheter infection rates when practitioners followed the institution's standard insertion algorithm. During phase II, an intervention of direct observation was added to the standard insertion procedure. The results demonstrated no change in utilization rates, however, CAUTI rates decreased from 2.24 to 0 per 1000 catheter days. The findings from this study may promote changes in clinical practice guidelines leading to a reduction in urinary catheter utilization and infection rates and improved patient outcomes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Confusing similar words: ERP correlates of lexical-semantic processing in first language attrition and late second language acquisition.

    Science.gov (United States)

    Kasparian, Kristina; Steinhauer, Karsten

    2016-12-01

    First language (L1) attrition is a socio-linguistic circumstance where second language (L2) learning coincides with changes in exposure and use of the native-L1. Attriters often report experiencing a decline in automaticity or proficiency in their L1 after a prolonged period in the L2 environment, while their L2 proficiency continues to strengthen. Investigating the neurocognitive correlates of attrition alongside those of late L2 acquisition addresses the question of whether the brain mechanisms underlying both L1 and L2 processing are strongly determined by proficiency, irrespective of whether the language was acquired from birth or in adulthood. Using event-related-potentials (ERPs), we examined lexical-semantic processing in Italian L1 attriters, compared to adult Italian L2 learners and to Italian monolingual native speakers. We contrasted the processing of classical lexical-semantic violations (Mismatch condition) with sentences that were equally semantically implausible but arguably trickier, as the target-noun was "swapped" with an orthographic neighbor that differed only in its final vowel and gender-marking morpheme (e.g., cappello (hat) vs. cappella (chapel)). Our aim was to determine whether sentences with such "confusable nouns" (Swap condition) would be processed as semantically correct by late L2 learners and L1 attriters, especially for those individuals with lower Italian proficiency scores. We found that lower-proficiency Italian speakers did not show significant N400 effects for Swap violations relative to correct sentences, regardless of whether Italian was the L1 or the L2. Crucially, N400 response profiles followed a continuum of "nativelikeness" predicted by Italian proficiency scores - high-proficiency attriters and high-proficiency Italian learners were indistinguishable from native controls, whereas attriters and L2 learners in the lower-proficiency range showed significantly reduced N400 effects for "Swap" errors. Importantly, attriters

  6. Personnel Attrition Rates in Historical Land Combat Operations: A Catalog of Attrition and Casualty Data Bases on Diskettes Usable with Personal Computers

    Science.gov (United States)

    1993-09-01

    Contemporary Electoral Processes; Political Partcipation; Public Opinion on Political Matters; Political Parties). XV. Orgaizaional Bhavio. (United...Pelaez (ed) Public Law and Comparative Politics. Trabajos en Homenaje a Ferran Vallis i Taberner, Vol XVII, Barcelona, Spain; Facultad de Derecho de

  7. [Observation of the effects of warming-up and role-playing in psychodrama in terms of mood rating].

    Science.gov (United States)

    Kawai, S

    1993-04-01

    The purpose is to make an appropriate list of terms that describe person's moment-to-moment changes in moods during psychodrama sessions. Seventy nurse students participated in a series of psychodrama sessions, consisting of a session of warming-up and two sessions of role playing. They rated their moods at the beginning of the sessions and after each session, on a five-point scale for each of the 55 terms, which were supposed to cover all kinds of moods during psychodrama sessions. After analyzing variations (using factor analyses) of subjects' ratings, three factors were found to be sufficient for describing their moods, and the terms in the list were eventually reduced to sixteen. Changes of moods analyzed through the ratings of sixteen scales were related significantly with subjects' performances of warming-up and role playing.

  8. Estimation of the variations of ventilation rate and indoor radon concentration using the observed wind velocity and indoor-outdoor temperature difference

    International Nuclear Information System (INIS)

    Nagano, Katsuhiro; Inose, Yuichi; Kojima, Hiroshi

    2006-01-01

    The indoor radon concentration in the building depends on the ventilation rate. Measurement results of indoor-outdoor pressure difference showed the ventilation rate correlated closely with the indoor-outdoor pressure difference. The observation results showed that one of factor of indoor-outdoor pressure difference was the wind velocity. When the wind velocity is small, the ventilation rate is affected by the indoor-outdoor temperature difference and the effect depends on the wind velocity. The temporal variation of indoor radon concentration was predicted by the time depending indoor radon balance model and the ventilation rate estimated from the wind velocity and the indoor-outdoor temperature difference. The temporal variations of predicted radon concentration gave good agreement with the experimental values. The measurement method, indoor radon concentration and ventilation rate, factors of temporal variation of ventilation rate, and prediction of indoor radon concentration are reported. (S.Y.)

  9. Emergency contraception with a copper IUD or oral levonorgestrel: an observational study of 1-year pregnancy rates.

    Science.gov (United States)

    Turok, David K; Jacobson, Janet C; Dermish, Amna I; Simonsen, Sara E; Gurtcheff, Shawn; McFadden, Molly; Murphy, Patricia A

    2014-03-01

    We investigated the 1-year pregnancy rates for emergency contraception (EC) users who selected the copper T380 intrauterine device (IUD) or oral levonorgestrel (LNG) for EC. This prospective study followed women for 1 year after choosing either the copper T380 IUD or oral LNG for EC. The study was powered to detect a 6% difference in pregnancy rates within the year after presenting for EC. Of the 542 women who presented for EC, agreed to participate in the trial and met the inclusion criteria, 215 (40%) chose the copper IUD and 327 (60%) chose oral LNG. In the IUD group, 127 (59%) were nulligravid. IUD insertion failed in 42 women (19%). The 1-year follow-up rate was 443/542 (82%); 64% of IUD users contacted at 1 year still had their IUDs in place. The 1-year cumulative pregnancy rate in women choosing the IUD was 6.5% vs. 12.2% in those choosing oral LNG [hazard ratio (HR) 0.53, 95% confidence interval (CI): 0.29-0.97, p=.041]. By type of EC method actually received, corresponding values were 5.2% for copper IUD users vs. 12.3% for oral LNG users (HR 0.42, 95% CI: 0.20-0.85, p=.017). A multivariable logistic regression model controlling for demographic variables demonstrates that women who chose the IUD for EC had fewer pregnancies in the following year than those who chose oral LNG (HR 0.50, 95% CI: 0.26-0.96, p=.037). One year after presenting for EC, women choosing the copper IUD for EC were half as likely to have a pregnancy compared to those choosing oral LNG. Compared to EC users who choose oral levonorgestrel, those who select the copper IUD have lower rates of pregnancy in the next year. Greater use of the copper IUD for EC may lower rates of unintended pregnancy in high-risk women. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Psychological and sociodemographic predictors of premature discontinuation of a 1-year multimodal outpatient weight-reduction program: an attrition analysis

    Directory of Open Access Journals (Sweden)

    Liebl ME

    2012-03-01

    Full Text Available Anne Ahnis1, Andrea Riedl1, Andrea Figura1, Elisabeth Steinhagen-Thiessen2, Max E Liebl3, Burghard F Klapp11Internal Medicine and Dermatology, Medical Department, Division of Psychosomatic Medicine, Charité – Universitätsmedizin Berlin, Campus Mitte, 2Internal Medicine with Gastroenterology and Nephrology, Specialty network of Gastroenterology, Endocrinology and Metabolic Diseases, Division of Lipid Metabolism, Charité – Universitätsmedizin Berlin, Campus Virchow-Klinikum, 3Medical Department, Division of Rheumatology and Clinical Immunology, Department for Physical Medicine, Charité – Universitätsmedizin Berlin, Campus Mitte, Berlin, GermanyObjective: Attrition rates of up to 77% have been reported in conservative weight-reduction programs for the treatment of obesity. In view of the cost of such programs to the health system, there is a need to identify the variables that predict premature discontinuation of treatment. Previous studies have focused mainly on somatic and sociodemographic parameters. The prospective influence of psychological factors has not been systematically investigated to date.Methods: A total of 164 patients (138 of whom were women with a mean age of 45 years and a mean body mass index of 39.57 participated in a 1-year outpatient weight-reduction program at the Charité – Universitätsmedizin Berlin University Hospital. The program included movement therapy, dietary advice, psychoeducational and behavioral interventions, relaxation procedures, and consultations with a specialist in internal medicine and a psychologist. Patients also underwent regular laboratory and psychological testing. The results were evaluated using a t-test, χ2-test, and logistic regression analysis.Results: Seventy-one of the 164 patients (61 women, mean age = 43 years, mean body mass index = 39.53 withdrew before the end of the program (attrition rate = 43.3%. While there were no differences between the somatic and metabolic

  11. Accurately Identifying New QoS Violation Driven by High-Distributed Low-Rate Denial of Service Attacks Based on Multiple Observed Features

    Directory of Open Access Journals (Sweden)

    Jian Kang

    2015-01-01

    Full Text Available We propose using multiple observed features of network traffic to identify new high-distributed low-rate quality of services (QoS violation so that detection accuracy may be further improved. For the multiple observed features, we choose F feature in TCP packet header as a microscopic feature and, P feature and D feature of network traffic as macroscopic features. Based on these features, we establish multistream fused hidden Markov model (MF-HMM to detect stealthy low-rate denial of service (LDoS attacks hidden in legitimate network background traffic. In addition, the threshold value is dynamically adjusted by using Kaufman algorithm. Our experiments show that the additive effect of combining multiple features effectively reduces the false-positive rate. The average detection rate of MF-HMM results in a significant 23.39% and 44.64% improvement over typical power spectrum density (PSD algorithm and nonparametric cumulative sum (CUSUM algorithm.

  12. Examining the Role of Race, Ethnicity, and Gender on Social and Behavioral Ratings within the Autism Diagnostic Observation Schedule

    Science.gov (United States)

    Harrison, Ashley J.; Long, Kristin A.; Tommet, Douglas C.; Jones, Richard N.

    2017-01-01

    The Autism Diagnostic Observation Schedule (ADOS) is widely used to assess symptoms of autism spectrum disorder (ASD). Given well-documented differences in social behaviors across cultures, this study examined whether item-level biases exist in ADOS scores across sociodemographic groups (race, ethnicity, and gender). We examined a subset of ten…

  13. On the Relationship between Observed NLDN Lightning Strikes and Modeled Convective Precipitation Rates Parameterization of Lightning NOx Production in CMAQ

    Science.gov (United States)

    Lightning-produced nitrogen oxides (NOX=NO+NO2) in the middle and upper troposphere play an essential role in the production of ozone (O3) and influence the oxidizing capacity of the troposphere. Despite much effort in both observing and modeling lightning NOX during the past dec...

  14. Plate rotations, fault slip rates, fault locking, and distributed deformation in northern Central America from 1999-2017 GPS observations

    Science.gov (United States)

    Ellis, A. P.; DeMets, C.; Briole, P.; Cosenza, B.; Flores, O.; Guzman-Speziale, M.; Hernandez, D.; Kostoglodov, V.; La Femina, P. C.; Lord, N. E.; Lasserre, C.; Lyon-Caen, H.; McCaffrey, R.; Molina, E.; Rodriguez, M.; Staller, A.; Rogers, R.

    2017-12-01

    We describe plate rotations, fault slip rates, and fault locking estimated from a new 100-station GPS velocity field at the western end of the Caribbean plate, where the Motagua-Polochic fault zone, Middle America trench, and Central America volcanic arc faults converge. In northern Central America, fifty-one upper-plate earthquakes caused approximately 40,000 fatalities since 1900. The proximity of main population centers to these destructive earthquakes and the resulting loss of human life provide strong motivation for studying the present-day tectonics of Central America. Plate rotations, fault slip rates, and deformation are quantified via a two-stage inversion of daily GPS position time series using TDEFNODE modeling software. In the first stage, transient deformation associated with three M>7 earthquakes in 2009 and 2012 is estimated and removed from the GPS position time series. In Stage 2, linear velocities determined from the corrected GPS time series are inverted to estimate deformation within the western Caribbean plate, slip rates along the Motagua-Polochic faults and faults in the Central America volcanic arc, and the gradient of extension in the Honduras-Guatemala wedge. Major outcomes of the second inversion include the following: (1) Confirmation that slip rates on the Motagua fault decrease from 17-18 mm/yr at its eastern end to 0-5 mm/yr at its western end, in accord with previous results. (2) A transition from moderate subduction zone locking offshore from southern Mexico and parts of southern Guatemala to weak or zero coupling offshore from El Salvador and parts of Nicaragua along the Middle America trench. (3) Evidence for significant east-west extension in southern Guatemala between the Motagua fault and volcanic arc. Our study also shows evidence for creep on the eastern Motagua fault that diminishes westward along the North America-Caribbean plate boundary.

  15. An increased estimate of the merger rate of double neutron stars from observations of a highly relativistic system.

    Science.gov (United States)

    Burgay, M; D'Amico, N; Possenti, A; Manchester, R N; Lyne, A G; Joshi, B C; McLaughlin, M A; Kramer, M; Sarkissian, J M; Camilo, F; Kalogera, V; Kim, C; Lorimer, D R

    2003-12-04

    The merger of close binary systems containing two neutron stars should produce a burst of gravitational waves, as predicted by the theory of general relativity. A reliable estimate of the double-neutron-star merger rate in the Galaxy is crucial in order to predict whether current gravity wave detectors will be successful in detecting such bursts. Present estimates of this rate are rather low, because we know of only a few double-neutron-star binaries with merger times less than the age of the Universe. Here we report the discovery of a 22-ms pulsar, PSR J0737-3039, which is a member of a highly relativistic double-neutron-star binary with an orbital period of 2.4 hours. This system will merge in about 85 Myr, a time much shorter than for any other known neutron-star binary. Together with the relatively low radio luminosity of PSR J0737-3039, this timescale implies an order-of-magnitude increase in the predicted merger rate for double-neutron-star systems in our Galaxy (and in the rest of the Universe).

  16. Supermassive Black Holes with High Accretion Rates in Active Galactic Nuclei. IX. 10 New Observations of Reverberation Mapping and Shortened Hβ Lags

    Science.gov (United States)

    Du, Pu; Zhang, Zhi-Xiang; Wang, Kai; Huang, Ying-Ke; Zhang, Yue; Lu, Kai-Xing; Hu, Chen; Li, Yan-Rong; Bai, Jin-Ming; Bian, Wei-Hao; Yuan, Ye-Fei; Ho, Luis C.; Wang, Jian-Min; SEAMBH collaboration

    2018-03-01

    As one paper in a series reporting on a large reverberation mapping campaign of super-Eddington accreting massive black holes (SEAMBHs) in active galactic nuclei (AGNs), we present the results of 10 SEAMBHs monitored spectroscopically during 2015–2017. Six of them are observed for the first time, and have generally higher 5100 Å luminosities than the SEAMBHs monitored in our campaign from 2012 to 2015; the remaining four are repeat observations to check if their previous lags change. Similar to the previous SEAMBHs, the Hβ time lags of the newly observed objects are shorter than the values predicted by the canonical R Hβ –L 5100 relation of sub-Eddington AGNs, by factors of ∼2–6, depending on the accretion rate. The four previously observed objects have lags consistent with previous measurements. We provide linear regressions for the R Hβ –L 5100 relation, solely for the SEAMBH sample and for low-accretion AGNs. We find that the relative strength of Fe II and the profile of the Hβ emission line can be used as proxies of accretion rate, showing that the shortening of Hβ lags depends on accretion rates. The recent SDSS-RM discovery of shortened Hβ lags in AGNs with low accretion rates provides compelling evidence for retrograde accretion onto the black hole. These evidences show that the canonical R Hβ –L 5100 relation holds only in AGNs with moderate accretion rates. At low accretion rates, it should be revised to include the effects of black hole spin, whereas the accretion rate itself becomes a key factor in the regime of high accretion rates.

  17. A Selective Mutism Arising from First Language Attrition, Successfully Treated with Paroxetine-CBT Combination Treatment.

    Science.gov (United States)

    Serra, Agostino; Di Mauro, Paola; Andaloro, Claudio; Maiolino, Luigi; Pavone, Piero; Cocuzza, Salvatore

    2015-10-01

    After immersion in a foreign language, speakers often have difficulty retrieving native-language words and may experience a decrease in its proficiency, this phenomenon, in the non-pathological form, is known as first language attrition. Self-perception of this low native-language proficiency and apprehension occurring when speaking is expected and, may sometimes lead these people to a state of social anxiety and, in extreme forms, can involve the withholding of speech as a primitive tool for self-protection, linking them to selective mutism. We report an unusual case of selective mutism arising from first language attrition in an Italian girl after attending a two-year "German language school", who successfully responded to a paroxetine-cognitive behavioral treatment (CBT) combination treatment.

  18. Proposed model for the high rate of rearrangement and rapid migration observed in some IncA/C plasmid lineages.

    Science.gov (United States)

    Meinersmann, R J; Lindsey, R L; Bono, J L; Smith, T P; Oakley, B B

    2013-08-01

    IncA/C plasmids are a class of plasmids from the Enterobacteriaceae that are relatively large (49 to >180 kbp), that are readily transferred by conjugation, and that carry multiple antimicrobial resistance genes. Reconstruction of the phylogeny of these plasmids has been difficult because of the high rate of remodeling by recombination-mediated horizontal gene transfer (HGT). We hypothesized that evaluation of nucleotide polymorphisms relative to the rate of HGT would help to develop a clock to show whether anthropic practices have had significant influences on the lineages of the plasmid. A system was developed to rapidly sequence up to 191 known open reading frames from each of 39 recently isolated IncA/C plasmids from a diverse panel of Salmonella enterica and Escherichia coli strains. With these data plus sequences from GenBank, we were able to distinguish six distinct lineages that had extremely low numbers of polymorphisms within each lineage, especially among the largest group designated as group 1. Two regions, each about half the plasmid in size, could be distinguished with a separate lineal pattern. The distribution of group 1 showed that it has migrated extremely rapidly with fewer polymorphisms than can be expected in 2,000 years. Remodeling by frequent HGT was evident, with a pattern that appeared to have the highest rate just upstream of the putative conjugation origin of transfer (oriT). It seems likely that when an IncA/C plasmid is transferred by conjugation there is an opportunity for plasmid remodeling adjacent to the oriT, which was also adjacent to a multiple antimicrobial resistance gene cassette.

  19. Rates of cognitive change in Alzheimer disease: Observations across a decade of placebo-controlled clinical trials with donepezil

    DEFF Research Database (Denmark)

    Jones, Roy W; Schwam, Elias; Wilkinson, David

    2009-01-01

    Treatment success in Alzheimer disease (AD) trials is generally based on benefits over placebo-treated controls. Consequently, variation in rates of decline among placebo-treated patients could impact outcomes from AD trials. In the present analyses, individual patient data [baseline Mini......-Mental State Examination (MMSE): 10 to 26] were pooled from randomized, placebo-controlled studies of donepezil for AD conducted during the 1990s, and grouped by initiation year-group 1: 1990 to 1994; group 2: 1996 to 1999. Changes in MMSE and Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS...

  20. Inter-disciplinary management of a patient with severely attrited teeth

    Directory of Open Access Journals (Sweden)

    Padmanabhan Shyam

    2010-01-01

    Full Text Available With increased awareness about dental esthetics, multidisciplinary periodontal therapy has begun to gain momentum. Management of severely attrited teeth is a challenging situation and is dealt with a multidisciplinary approach. In cases of severe tooth wear, the crown height is drastically reduced, in some cases up to the gingival level. This might require a contribution from the disciplines of endodontics, periodontics, orthodontics and prosthodontics for predictable results. Herein we describe the management of one such case.

  1. Attrition of Dolomitic Lime in a Fluidized-Bed at High Temperature

    Czech Academy of Sciences Publication Activity Database

    Hartman, Miloslav; Svoboda, Karel; Pohořelý, Michael; Šyc, Michal; Jeremiáš, Michal

    2013-01-01

    Roč. 67, č. 2 (2013), s. 164-172 ISSN 0366-6352 R&D Projects: GA AV ČR IAA400720701; GA MŠk(CZ) 7C11009 Grant - others:RFCS(XE) RFCR-CT-2010-00009 Institutional support: RVO:67985858 Keywords : attrition * catalytic gasification * dolomitic lime Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.193, year: 2013

  2. Attrition, elutriation, and growth of particles produced in fluidized-bed waste calciners

    International Nuclear Information System (INIS)

    McDonald, F.N.

    1982-09-01

    The Idaho Chemical Processing Plant reduces the volume of high-level liquid radioactive wastes in a fluidized bed to produce a granular calcine product. In the past, difficulties have been experienced in controlling the product's particle size when processing certain blends of sodium-bearing waste. Therefore, experiments in attrition, elutriation, and particle growth were done to characterize how best to control these three parameters. 15 figures, 16 tables

  3. Nanostructuring of Aluminum Alloy Powders by Cryogenic Attrition with Hydrogen-Free Process Control Agent

    Science.gov (United States)

    2015-02-01

    Nanostructuring of Aluminum Alloy Powders by Cryogenic Attrition with Hydrogen-Free Process Control Agent by Frank Kellogg , Clara Hofmeister...Process Control Agent Frank Kellogg Bowhead Science and Technology Clara Hofmeister Advanced Materials Processing and Analysis Center...NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Frank Kellogg , Clara Hofmeister, Anit Giri, and Kyu Cho 5d. PROJECT NUMBER 5e

  4. Effect of acidity upon attrition-corrosion of human dental enamel.

    Science.gov (United States)

    Wu, Yun-Qi; Arsecularatne, Joseph A; Hoffman, Mark

    2015-04-01

    Attrition-corrosion is a synthesized human enamel wear process combined mechanical effects (attrition) with corrosion. With the rising consumption of acidic food and beverages, attrition-corrosion is becoming increasingly common. Yet, research is limited and the underlying mechanism remains unclear. In this study, in vitro wear loss of human enamel was investigated and the attrition-corrosion process and wear mechanism were elucidated by the analysis of the wear scar and its subsurface using focused ion beam (FIB) sectioning and scanning electron microscopy (SEM). Human enamel flat-surface samples were prepared with enamel cusps as the wear antagonists. Reciprocating wear testing was undertaken under load of 5N at the speed of 66 cycle/min for 2250 cycles with lubricants including citric acid (at pH 3.2 and 5.5), acetic acid (at pH 3.2 and 5.5) and distilled water. All lubricants were used at 37°C. Similar human enamel flat-surface samples were also exposed to the same solutions as a control group. The substance loss of enamel during wear can be linked to the corrosion potential of a lubricant used. Using a lubricant with very low corrosion potential (such as distilled water), the wear mechanism was dominated by delamination with high wear loss. Conversely, the wear mechanism changed to shaving of the softened layer with less material loss in an environment with medium corrosion potential such as citric acid at pH 3.2 and 5.5 and acetic acid at pH 5.5. However, a highly corrosive environment (e.g., acetic acid at pH 3.2) caused the greatest loss of substance during wear. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Radiation-chemical discussion on inverse dose-rate effect observed in radiation-induced strand breaks of plasmid DNA

    International Nuclear Information System (INIS)

    Masuda, Takahiro

    1994-01-01

    Experimental results of inverse dose-rate effect, so-called Kada Effects, which was published by Takakura and her coworkers on radiation-induced strand breaks of plasmid DNA in aerated aqueous solution, have been kinetically analyzed and discussed on the basis of radiation chemistry. the kinetic analysis indicates that there are two possible mechanisms; 1) equilibrium mixture of O 2 - and HO 2 is responsible for strand breaks of DNA, and 2) peroxyl radical produced from citrate is effective for the strand breaks. However, the detailed kinetic analysis revealed that the latter is improbable because unimolecular decay of the peroxyl radical must be assumed to be negligible for its participation despite fast decay of analogous organic peroxyl radicals. The analysis has also given 9.93±0.10 dm 3 mol -1 s -1 per nucleotide unit, which corresponds to 7.62 x 10 4 dm 3 mol -1 s -1 per DNA molecule, as the rate constant for the reaction of the equilibrium mixture with plasmid pBR 322 DNA. Furthermore the probability that the reaction of the mixture with a nucleotide unit of DNA leads to strand breaks was obtained to be 3.36 x 10 -3 for gamma-irradiated system and 1.98 x 10 -3 for beta-irradiated system, respectively. (author)

  6. Flue gas desulfurization under simulated oxyfiring fluidized bed combustion conditions: The influence of limestone attrition and fragmentation

    Energy Technology Data Exchange (ETDEWEB)

    Scala, F.; Salatino, P. [CNR, Naples (Italy)

    2010-01-01

    Flue gas desulfurization by means of limestone injection under simulated fluidized bed oxyfiring conditions was investigated, with a particular focus on particle attrition and fragmentation phenomena. An experimental protocol was applied, based on the use of complementary techniques that had been previously developed for the characterization of attrition of sorbents in air-blown atmospheric fluidized bed combustors. The extent and pattern of limestone attrition by surface wear in the dense phase of a fluidized bed were assessed in bench scale fluidized bed experiments under simulated oxyfiring conditions. Sorbent samples generated during the oxyfiring tests were further characterized from the standpoint of fragmentation upon high velocity impact by means of a particle impactor. The experimental results were compared with those previously obtained with the same limestone under air-blown atmospheric fluidized bed combustion conditions. The profound differences in the attrition and fragmentation extents and patterns associated with oxyfiring as compared to air-blown atmospheric combustion and the role played by the different attrition/fragmentation paths were highlighted. In particular, it was noted that attrition could effectively enhance particle sulfation under oxyfiring conditions by continuously disclosing unconverted calcium to the sulfur-bearing atmosphere.

  7. Toxicities Affecting Quality of Life After Chemo-IMRT of Oropharyngeal Cancer: Prospective Study of Patient-Reported, Observer-Rated, and Objective Outcomes

    International Nuclear Information System (INIS)

    Hunter, Klaudia U.; Schipper, Matthew; Feng, Felix Y.; Lyden, Teresa; Haxer, Mark; Murdoch-Kinch, Carol-Anne; Cornwall, Benjamin; Lee, Connie S.Y.; Chepeha, Douglas B.; Eisbruch, Avraham

    2013-01-01

    Purpose: To test the hypothesis that intensity modulated radiation therapy (IMRT) aiming to spare the salivary glands and swallowing structures would reduce or eliminate the effects of xerostomia and dysphagia on quality of life (QOL). Methods and Materials: In this prospective, longitudinal study, 72 patients with stage III-IV oropharyngeal cancer were treated uniformly with definitive chemo-IMRT sparing the salivary glands and swallowing structures. Overall QOL was assessed by summary scores of the Head Neck QOL (HNQOL) and University of Washington QOL (UWQOL) questionnaires, as well as the HNQOL “Overall Bother” question. Quality of life, observer-rated toxicities (Common Toxicity Criteria Adverse Effects scale, version 2), and objective evaluations (videofluoroscopy assessing dysphagia and saliva flow rates assessing xerostomia) were recorded from before therapy through 2 years after therapy. Correlations between toxicities/objective evaluations and overall QOL were assessed using longitudinal repeated measures of analysis and Pearson correlations. Results: All observer-rated toxicities and QOL scores worsened 1-3 months after therapy and improved through 12 months, with minor further improvements through 24 months. At 12 months, dysphagia grades 0-1, 2, and 3, were observed in 95%, 4%, and 1% of patients, respectively. Using all posttherapy observations, observer-rated dysphagia was highly correlated with all overall QOL measures (P<.0001), whereas xerostomia and mucosal and voice toxicities were significantly correlated with some, but not all, overall QOL measures, with lower correlation coefficients than dysphagia. Late overall QOL (≥6 or ≥12 months after therapy) was primarily associated with observer-rated dysphagia, and to a lesser extent with xerostomia. Videofluoroscopy scores, but not salivary flows, were significantly correlated with some of the overall QOL measures. Conclusion: After chemo-IMRT, although late dysphagia was on average mild

  8. Toxicities Affecting Quality of Life After Chemo-IMRT of Oropharyngeal Cancer: Prospective Study of Patient-Reported, Observer-Rated, and Objective Outcomes

    Energy Technology Data Exchange (ETDEWEB)

    Hunter, Klaudia U. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Schipper, Matthew [Department of Biostatistics, University of Michigan, Ann Arbor, Michigan (United States); Feng, Felix Y. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Lyden, Teresa; Haxer, Mark [Department of Speech-Language Pathology, University of Michigan, Ann Arbor, Michigan (United States); Murdoch-Kinch, Carol-Anne; Cornwall, Benjamin [Department of Hospital Dentistry, University of Michigan, Ann Arbor, Michigan (United States); Lee, Connie S.Y. [Department of Biostatistics, University of Michigan, Ann Arbor, Michigan (United States); Chepeha, Douglas B. [Department of Otolaryngology-Head Neck Surgery, University of Michigan, Ann Arbor, Michigan (United States); Eisbruch, Avraham, E-mail: Eisbruch@umich.edu [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)

    2013-03-15

    Purpose: To test the hypothesis that intensity modulated radiation therapy (IMRT) aiming to spare the salivary glands and swallowing structures would reduce or eliminate the effects of xerostomia and dysphagia on quality of life (QOL). Methods and Materials: In this prospective, longitudinal study, 72 patients with stage III-IV oropharyngeal cancer were treated uniformly with definitive chemo-IMRT sparing the salivary glands and swallowing structures. Overall QOL was assessed by summary scores of the Head Neck QOL (HNQOL) and University of Washington QOL (UWQOL) questionnaires, as well as the HNQOL “Overall Bother” question. Quality of life, observer-rated toxicities (Common Toxicity Criteria Adverse Effects scale, version 2), and objective evaluations (videofluoroscopy assessing dysphagia and saliva flow rates assessing xerostomia) were recorded from before therapy through 2 years after therapy. Correlations between toxicities/objective evaluations and overall QOL were assessed using longitudinal repeated measures of analysis and Pearson correlations. Results: All observer-rated toxicities and QOL scores worsened 1-3 months after therapy and improved through 12 months, with minor further improvements through 24 months. At 12 months, dysphagia grades 0-1, 2, and 3, were observed in 95%, 4%, and 1% of patients, respectively. Using all posttherapy observations, observer-rated dysphagia was highly correlated with all overall QOL measures (P<.0001), whereas xerostomia and mucosal and voice toxicities were significantly correlated with some, but not all, overall QOL measures, with lower correlation coefficients than dysphagia. Late overall QOL (≥6 or ≥12 months after therapy) was primarily associated with observer-rated dysphagia, and to a lesser extent with xerostomia. Videofluoroscopy scores, but not salivary flows, were significantly correlated with some of the overall QOL measures. Conclusion: After chemo-IMRT, although late dysphagia was on average mild

  9. A partnered approach for structured observation to assess the environment of a neighborhood with high diabetes rates.

    Science.gov (United States)

    Kleinman, Lawrence C; Lutz, David; Plumb, Ellen J; Barkley, Pearl; Nazario, Hector R; Ramos, Michelle A; Horowitz, Carol R

    2011-01-01

    The Communities IMPACT Diabetes Center uses partnered methods to address diabetes-related conditions among African Americans and Latinos in East Harlem, New York. To describe a novel, partnered approach that integrates simultaneous structured observation by community and academic partners with "on-the-spot" resolution of differences to collect baseline data regarding the built and food environments in a two census tract area of East Harlem and present select findings. We designed an environmental assessment to explore characteristics of the environment related to walking and eating. We paired community and academic partners to assess each block, resolve any differences, and report results. Nearly one year later, we surveyed the data collectors and analyzed responses using standard qualitative methods. Key themes included connection to and characteristics of the community; interactions with partners; surprises and learning, and aspects of data collection. All but the first were common to academic and community partners. Relationships between partners were generally amiable. Both community-"I think it was very helpful, we made sure neither of us made mistakes, and helped each other when we could"-and academic-"I really enjoyed it . . . I learned a lot about the areas I surveyed"-partners were complimentary. Community partners' strengths included local knowledge of the community, whereas academic partners' focus on adherence to the specifications was critical. Structured observation identified many sidewalks in disrepair or obstructed, few benches, and highly variable times allocated for pedestrians to cross at cross walks. The partnered data collection was both successful and formative, building additional relationships and further capacity for ongoing partnership. Community partners saw their community in a new way, seeing, "little things that are important but people don't pay attention to." Structured observations added to our understanding of how an environment

  10. Observation of low-lying resonances in the quasicontinuum of 195,196Pt and enhanced astrophysical reaction rates

    Directory of Open Access Journals (Sweden)

    Giacoppo F.

    2015-01-01

    Full Text Available An excess of strength on the low-energy tail of the giant dipole resonance recently has been observed in the γ-decay from the quasicontinuum of 195,196Pt. The nature of this phenomenon is not yet fully investigated. If this feature is present also in the γ-ray strength of the neutron-rich isotopes, it can affect the neutron-capture reactions involved in the formation of heavy-elements in stellar nucleosynthesis. The experimental level density and γ-ray strength function of 195,196Pt are presented together with preliminary calculations of the corresponding neutron-capture cross sections.

  11. Factors affecting employee attrition among engineers and non-engineers in manufacturing industry

    Directory of Open Access Journals (Sweden)

    Bhardwaj, Shikha

    2017-12-01

    Full Text Available Almost every industry nowadays is badly affected by attrition. Retention of talented employees is the biggest problem faced by India Incorporation. In order to gather more insights on the talent crunch, the undertaken study was conducted on technical and non-technical jobs in manufacturing sector in Delhi NCR. Research has identified three major factors – Salary, Boss and Stress in the jobs after conducted interviews with around 50 technical and non-technical respondents. A set of questions were prepared and send to 120 employee but only 75 responded. The study shows a strong relationship between type of job and factors of attrition. Chi-square test clearly states strong relationship among two. Thus, any change in one will affect the other also. At the same time other important outcomes were that for technical jobs salary is the most important factor whereas non-technical Boss is the factor. Out 75, 63 were engineer and rest were non-engineer. The research can be further done to understand factors of attrition with other demographic variable.

  12. The Authoritarian Personality in Emerging Adulthood: Longitudinal Analysis Using Standardized Scales, Observer Ratings, and Content Coding of the Life Story.

    Science.gov (United States)

    Peterson, Bill E; Pratt, Michael W; Olsen, Janelle R; Alisat, Susan

    2016-04-01

    Three different methods (a standardized scale, an observer-based Q-sort, and content coding of narratives) were used to study the continuity of authoritarianism longitudinally in emerging and young adults. Authoritarianism was assessed in a Canadian sample (N = 92) of men and women at ages 19 and 32 with Altemeyer's (1996) Right-Wing Authoritarianism (RWA) Scale. In addition, components of the authoritarian personality were assessed at age 26 through Q-sort observer methods (Block, 2008) and at age 32 through content coding of life stories. Age 19 authoritarianism predicted the Q-sort and life story measures of authoritarianism. Two hierarchical regression analyses showed that the Q-sort and life story measures of authoritarianism also predicted the RWA scale at age 32 beyond educational level and parental status, and even after the inclusion of age 19 RWA. Differences and similarities in the pattern of correlates for the Q-sort and life story measures are discussed, including the overall lack of results for authoritarian aggression. Content in narratives may be the result of emerging adult authoritarianism and may serve to maintain levels of authoritarianism in young adulthood. © 2014 Wiley Periodicals, Inc.

  13. Correlation of a hypoxia based tumor control model with observed local control rates in nasopharyngeal carcinoma treated with chemoradiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Avanzo, Michele; Stancanello, Joseph; Franchin, Giovanni; Sartor, Giovanna; Jena, Rajesh; Drigo, Annalisa; Dassie, Andrea; Gigante, Marco; Capra, Elvira [Department of Medical Physics, Centro di Riferimento Oncologico, Aviano 33081 (Italy); Research and Clinical Collaborations, Siemens Healthcare, Erlangen 91052 (Germany); Department of Radiation Oncology, Centro di Riferimento Oncologico, Aviano 33081 (Italy); Department of Medical Physics, Centro di Riferimento Oncologico, Aviano 33081 (Italy); Oncology Centre, Cambridge University Hospitals NHS Foundation Trust, Cambridge CB2 0QQ (United Kingdom); Department of Medical Physics, Centro di Riferimento Oncologico, Aviano 33081 (Italy); Department of Radiation Oncology, Centro di Riferimento Oncologico, Aviano 33081 (Italy); Department of Medical Physics, Centro di Riferimento Oncologico, Aviano 33081 (Italy)

    2010-04-15

    Purpose: To extend the application of current radiation therapy (RT) based tumor control probability (TCP) models of nasopharyngeal carcinoma (NPC) to include the effects of hypoxia and chemoradiotherapy (CRT). Methods: A TCP model is described based on the linear-quadratic model modified to account for repopulation, chemotherapy, heterogeneity of dose to the tumor, and hypoxia. Sensitivity analysis was performed to determine which parameters exert the greatest influence on the uncertainty of modeled TCP. On the basis of the sensitivity analysis, the values of specific radiobiological parameters were set to nominal values reported in the literature for NPC or head and neck tumors. The remaining radiobiological parameters were determined by fitting TCP to clinical local control data from published randomized studies using both RT and CRT. Validation of the model was performed by comparison of estimated TCP and average overall local control rate (LCR) for 45 patients treated at the institution with conventional linear-accelerator-based or helical tomotherapy based intensity-modulated RT and neoadjuvant chemotherapy. Results: Sensitivity analysis demonstrates that the model is most sensitive to the radiosensitivity term {alpha} and the dose per fraction. The estimated values of {alpha} and OER from data fitting were 0.396 Gy{sup -1} and 1.417. The model estimate of TCP (average 90.9%, range 26.9%-99.2%) showed good correlation with the LCR (86.7%). Conclusions: The model implemented in this work provides clinicians with a useful tool to predict the success rate of treatment, optimize treatment plans, and compare the effects of multimodality therapy.

  14. Correlation of a hypoxia based tumor control model with observed local control rates in nasopharyngeal carcinoma treated with chemoradiotherapy

    International Nuclear Information System (INIS)

    Avanzo, Michele; Stancanello, Joseph; Franchin, Giovanni; Sartor, Giovanna; Jena, Rajesh; Drigo, Annalisa; Dassie, Andrea; Gigante, Marco; Capra, Elvira

    2010-01-01

    Purpose: To extend the application of current radiation therapy (RT) based tumor control probability (TCP) models of nasopharyngeal carcinoma (NPC) to include the effects of hypoxia and chemoradiotherapy (CRT). Methods: A TCP model is described based on the linear-quadratic model modified to account for repopulation, chemotherapy, heterogeneity of dose to the tumor, and hypoxia. Sensitivity analysis was performed to determine which parameters exert the greatest influence on the uncertainty of modeled TCP. On the basis of the sensitivity analysis, the values of specific radiobiological parameters were set to nominal values reported in the literature for NPC or head and neck tumors. The remaining radiobiological parameters were determined by fitting TCP to clinical local control data from published randomized studies using both RT and CRT. Validation of the model was performed by comparison of estimated TCP and average overall local control rate (LCR) for 45 patients treated at the institution with conventional linear-accelerator-based or helical tomotherapy based intensity-modulated RT and neoadjuvant chemotherapy. Results: Sensitivity analysis demonstrates that the model is most sensitive to the radiosensitivity term α and the dose per fraction. The estimated values of α and OER from data fitting were 0.396 Gy -1 and 1.417. The model estimate of TCP (average 90.9%, range 26.9%-99.2%) showed good correlation with the LCR (86.7%). Conclusions: The model implemented in this work provides clinicians with a useful tool to predict the success rate of treatment, optimize treatment plans, and compare the effects of multimodality therapy.

  15. Observations of white-light flares in NOAA active region 11515: high occurrence rate and relationship with magnetic transients

    Science.gov (United States)

    Song, Y. L.; Tian, H.; Zhang, M.; Ding, M. D.

    2018-06-01

    Aims: There are two goals in this study. One is to investigate how frequently white-light flares (WLFs) occur in a flare-productive active region (NOAA active region 11515). The other is to investigate the relationship between WLFs and magnetic transients (MTs). Methods: We used the high-cadence (45 s) full-disk continuum filtergrams and line-of-sight magnetograms taken by the Helioseismic and Magnetic Imager (HMI) on board the Solar Dynamics Observatory (SDO) to identify WLFs and MTs, respectively. Images taken by the Atmospheric Imaging Assembly (AIA) on board SDO were also used to show the flare morphology in the upper atmosphere. Results: We found at least 20 WLFs out of a total of 70 flares above C class (28.6%) in NOAA active region 11515 during its passage across the solar disk (E45°-W45°). Each of these WLFs occurred in a small region, with a short duration of about 5 min. The enhancement of the white-light continuum intensity is usually small, with an average enhancement of 8.1%. The 20 WLFs we observed were found along an unusual configuration of the magnetic field that was characterized by a narrow ribbon of negative field. Furthermore, the WLFs were found to be accompanied by MTs, with radical changes in magnetic field strength (or even a sign reversal) observed during the flare. In contrast, there is no obvious signature of MTs in the 50 flares without white-light enhancements. Conclusions: Our results suggest that WLFs occur much more frequently than previously thought, with most WLFs being fairly weak enhancements. This may explain why WLFs are reported rarely. Our observations also suggest that MTs and WLFs are closely related and appear cospatial and cotemporal, when considering HMI data. A greater enhancement of WL emission is often accompanied by a greater change in the line-of-sight component of the unsigned magnetic field. Considering the close relationship between MTs and WLFs, many previously reported flares with MTs may be WLFs. The movie

  16. An investigation of forecast horizon and observation fit’s influence on an econometric rate forecast model in the liner shipping industry

    DEFF Research Database (Denmark)

    Nielsen, Peter; Jiang, Liping; Rytter, Niels Gorm Malý

    2014-01-01

    This paper evaluates the influence of forecast horizon and observation fit on the robustness and performance of a specific freight rate forecast model used in the liner shipping industry. In the first stage of the research, a forecast model used to predict container freight rate development...... of the forecast horizon and observation fit and their interactions on the forecast model's performance. The results underline the complicated nature of creating a suitable forecast model by balancing business needs, a desire to fit a good model and achieve high accuracy. There is strong empirical evidence from...... this study; that a robust model is preferable, that overfitting is a true danger, and that a balance must be achieved between forecast horizon and the number of observations used to fit the model. In addition, methodological guidance has also been provided on how to test, design, and choose the superior...

  17. Relative risk of home hemodialysis attrition in patients using a telehealth platform.

    Science.gov (United States)

    Weinhandl, Eric D; Collins, Allan J

    2017-12-06

    Home hemodialysis (HHD) facilitates increased treatment frequency, which may improve patient outcomes. However, attrition due to technique failure limits the clinical effectiveness of the modality. Nx2me Connected Health is a telehealth platform that enables ongoing assessment of HHD patients using NxStage equipment, and that may reduce patient burden. We aimed to assess whether use of Nx2me was associated with risk of HHD attrition. We compared risks of all-cause attrition, dialysis cessation (i.e., death or transplant), and technique failure in Nx2me users and matched control patients, using a retrospective cohort study. We also compared the likelihood of HHD training graduation in patients who initiated use of Nx2me during training with the likelihood in matched control patients. Matching factors included date of HHD initiation, NxStage treatment duration at initiation of follow-up, and prescribed treatment frequency. We used stratified Fine-Gray and Cox regression to compare risks, with adjustment for demographic factors and vascular access modality, and stratification by matched cluster. We identified 606 Nx2me users; 49.5% initiated use of Nx2me in NxStage equipment. Adjusted hazard ratios (AHRs) of all-cause attrition, dialysis cessation, and technique failure were 0.80 (95% confidence interval, 0.68-0.95), 1.10 (0.86-1.41), and 0.71 (0.57-0.87), respectively, for Nx2me users vs. matched controls. AHRs were similar in patients who initiated use of Nx2me in <3 months after initiation of HHD. The AHR of HHD training graduation was 1.61 (1.10-2.36) in patients who initiated use of Nx2me within 2 weeks of training initiation vs. matched controls. Use of Nx2me was associated with lower risk of all-cause attrition, lower risk of technique failure, and higher likelihood of HHD training graduation. Further studies are needed to identify the mechanisms by which use of a telehealth platform may improve clinical outcomes and reduce patient burden. © 2017 The Authors

  18. Observer success rates for identification of 3D surface reconstructed facial images and implications for patient privacy and security

    Science.gov (United States)

    Chen, Joseph J.; Siddiqui, Khan M.; Fort, Leslie; Moffitt, Ryan; Juluru, Krishna; Kim, Woojin; Safdar, Nabile; Siegel, Eliot L.

    2007-03-01

    3D and multi-planar reconstruction of CT images have become indispensable in the routine practice of diagnostic imaging. These tools cannot only enhance our ability to diagnose diseases, but can also assist in therapeutic planning as well. The technology utilized to create these can also render surface reconstructions, which may have the undesired potential of providing sufficient detail to allow recognition of facial features and consequently patient identity, leading to violation of patient privacy rights as described in the HIPAA (Health Insurance Portability and Accountability Act) legislation. The purpose of this study is to evaluate whether 3D reconstructed images of a patient's facial features can indeed be used to reliably or confidently identify that specific patient. Surface reconstructed images of the study participants were created used as candidates for matching with digital photographs of participants. Data analysis was performed to determine the ability of observers to successfully match 3D surface reconstructed images of the face with facial photographs. The amount of time required to perform the match was recorded as well. We also plan to investigate the ability of digital masks or physical drapes to conceal patient identity. The recently expressed concerns over the inability to truly "anonymize" CT (and MRI) studies of the head/face/brain are yet to be tested in a prospective study. We believe that it is important to establish whether these reconstructed images are a "threat" to patient privacy/security and if so, whether minimal interventions from a clinical perspective can substantially reduce this possibility.

  19. Assessing the influence of risk factors on rates and dynamics of peripheral vein phlebitis: an observational cohort study.

    Science.gov (United States)

    Mestre Roca, Gabriel; Berbel Bertolo, Cristina; Tortajada Lopez, Purificación; Gallemi Samaranch, Gema; Aguilar Ramirez, Mari Carmen; Caylà Buqueras, Joan; Rodríguez-Baño, Jesús; Martinez, José Antonio

    2012-07-21

    To assess the influence of risk factors on the rates and kinetics of peripheral vein phlebitis (PVP) development and its theoretical influence in absolute PVP reduction after catheter replacement. All peripheral short intravenous catheters inserted during one month were included (1201 catheters and 967 patients). PVP risk factors were assessed by a Cox proportional hazard model. Cumulative probability, conditional failure of PVP and theoretical estimation of the benefit from replacement at different intervals were performed. Female gender, catheter insertion at the emergency or medical-surgical wards, forearm site, amoxicillin-clavulamate or aminoglycosides were independent predictors of PVP with hazard ratios (95 confidence interval) of 1.46 (1.09-2.15), 1.94 (1.01-3.73), 2.51 (1.29-4.88), 1.93 (1.20-3.01), 2.15 (1.45-3.20) and 2.10 (1.01-4.63), respectively. Maximum phlebitis incidence was reached sooner in patients with ≥2 risk factors (days 3-4) than in those with phlebitis/one catheter-day for devices with ≤1 risk factors to 0.26 for those with ≥3. The greatest benefit of routine catheter exchange was obtained by replacement every 60h. However, this benefit differed according to the number of risk factors: 24.8% reduction with ≥3, 13.1% with 2, and 9.2% with ≤1. PVP dynamics is highly influenced by identifiable risk factors which may be used to refine the strategy of catheter management. Routine replacement every 72h seems to be strictly necessary only in high-risk catheters. Copyright © 2011 Elsevier España, S.L. All rights reserved.

  20. Investigation of factors influencing the attrition breakage of coal

    Energy Technology Data Exchange (ETDEWEB)

    Oberholzer, V.; van der Walt, J. [North West University, Mmabatho (South Africa). School of Chemical & Minerals Engineering

    2009-04-15

    The presence of fines (particles smaller than 6 mm in diameter) causes hydrodynamic problems in gasifiers and therefore it is of great importance to minimize the amount of fine coal in the feed. This serves as motivation for understanding coal's breakage mechanisms, which could lead to the ability to predict the generation of fines. The aim of this project was to simulate the pulsating effect of the conveyor belt in order to investigate factors influencing the breakage. Results indicated that an increased initial particle size had an increasing effect in the amount of fines generated. Weathering had an insignificant effect on the breakage of coal. To conclude, a breakage model was developed to describe the rate of breakage out of the top size when a combination of two breakage modes is present.

  1. Attrition of Knowledge Workforce in Healthcare in Northern parts of India – Health Information Technology as a Plausible Retention Strategy

    Directory of Open Access Journals (Sweden)

    Indrajit Bhattacharya

    2012-06-01

    Full Text Available Faced with a global shortage of skilled health workers due to attrition, countries are struggling to build and maintain optimum knowledge workforce in healthcare for delivering quality healthcare services. Forces that affect healthcare professionals’ turnover needs to be addressed before a competent uniformly adoptable strategy could be proposed for mitigating the problem. In this study we investigate the effects of the socio–demographic characteristics on attrition of healthcare knowledge workforce in northern parts of India that have a wide gradient of rural and urban belt, taking into account both public and private healthcare organizations. For this purpose healthcare professional attrition tracking survey (HATS was designed. The data has been collected from a random sample of 807 respondents consisting of doctors, nurses, paramedics and administrators to explore the relationships between various factors acting as antecedents in affecting the job satisfaction, commitment and intention of a healthcare professional to stay in the job. Structured questionnaires were utilized as the data collection tools. Descriptive statistics, factor analysis and path analysis were carried out using multiple regression and correlation to propose a model that best explains the theoretical assumption of factors leading to attrition. Six factors of attrition namely compensation and perks, work life balance, sense of accomplishment, work load, need for automation and technology improvement, substandard nature of work have been identified as the main factors with a data reliability of 0.809%. It has also been identified that the intention to shift is a major decision maker that affects attrition and in turn affected by job satisfaction dimensions. Based on the survey response and analysis, a highly possible strategy of utilizing information technology implementation for increasing worker motivation, job satisfaction and commitment to reduce attrition has been

  2. Non-technical skills evaluation in the critical care air ambulance environment: introduction of an adapted rating instrument--an observational study.

    Science.gov (United States)

    Myers, Julia A; Powell, David M C; Psirides, Alex; Hathaway, Karyn; Aldington, Sarah; Haney, Michael F

    2016-03-08

    In the isolated and dynamic health-care setting of critical care air ambulance transport, the quality of clinical care is strongly influenced by non-technical skills such as anticipating, recognising and understanding, decision making, and teamwork. However there are no published reports identifying or applying a non-technical skills framework specific to an intensive care air ambulance setting. The objective of this study was to adapt and evaluate a non-technical skills rating framework for the air ambulance clinical environment. In the first phase of the project the anaesthetists' non-technical skills (ANTS) framework was adapted to the air ambulance setting, using data collected directly from clinician groups, published literature, and field observation. In the second phase experienced and inexperienced inter-hospital transport clinicians completed a simulated critical care air transport scenario, and their non-technical skills performance was independently rated by two blinded assessors. Observed and self-rated general clinical performance ratings were also collected. Rank-based statistical tests were used to examine differences in the performance of experienced and inexperienced clinicians, and relationships between different assessment approaches and assessors. The framework developed during phase one was referred to as an aeromedical non-technical skills framework, or AeroNOTS. During phase two 16 physicians from speciality training programmes in intensive care, emergency medicine and anaesthesia took part in the clinical simulation study. Clinicians with inter-hospital transport experience performed more highly than those without experience, according to both AeroNOTS non-technical skills ratings (p = 0.001) and general performance ratings (p = 0.003). Self-ratings did not distinguish experienced from inexperienced transport clinicians (p = 0.32) and were not strongly associated with either observed general performance (r(s) = 0.4, p = 0

  3. Real-Time Observation of Apathy in Long-Term Care Residents With Dementia: Reliability of the Person-Environment Apathy Rating Scale.

    Science.gov (United States)

    Jao, Ying-Ling; Mogle, Jacqueline; Williams, Kristine; McDermott, Caroline; Behrens, Liza

    2018-04-01

    Apathy is prevalent in individuals with dementia. Lack of responsiveness to environmental stimulation is a key characteristic of apathy. The Person-Environment Apathy Rating (PEAR) scale consists of environment and apathy subscales, which allow for examination of environmental impact on apathy. The interrater reliability of the PEAR scale was examined via real-time observation. The current study included 45 observations of 15 long-term care residents with dementia. Each participant was observed at three time points for 10 minutes each. Two raters observed the participant and surrounding environment and independently rated the participant's apathy and environmental stimulation using the PEAR scale. Weighted Kappa was 0.5 to 0.82 for the PEAR-Environment subscale and 0.5 to 0.8 for the PEAR-Apathy subscale. Overall, with the exception of three items with relatively weak reliability (0.50 to 0.56), the PEAR scale showed moderate to strong interrater reliability (0.63 to 0.82). The results support the use of the PEAR scale to measure environmental stimulation and apathy via real-time observation in long-term care residents with dementia. [Journal of Gerontological Nursing, 44(4), 23-28.]. Copyright 2018, SLACK Incorporated.

  4. Refinement of Crystalline Boron and the Superconducting Properties of MgB2 by Attrition Ball Milling

    International Nuclear Information System (INIS)

    Lee, J. H.; Shin, S. Y.; Park, H. W.; Jun, B. H.; Kim, C. J.

    2008-01-01

    We report refinement of crystalline boron by an attrition ball milling system and the superconducting properties of the MgB 2 pellets prepared from the refined boron. In this work, we have conducted the ball milling with only crystalline boron powder, in order to improve homogeneity and control the grain size of the MgB 2 that is formed from it. We observed that the crystalline responses in the ball-milled boron became broader and weaker when the ball-milling time was further increased. On the other hand, the B 2 O 3 peak became stronger in the powders, resulting in an increase in the amount of MgO within the MgB 2 volume. The main reason for this is a greater oxygen uptake. From the perspective of the superconducting properties, however, the sample prepared from boron that was ball milled for 5 hours showed an improvement of critical current density (J c ), even with increased MgO phase, under an external magnetic field at 5 and 20 K.

  5. Examining the impact of introducing ICD-MM on observed trends in maternal mortality rates in the UK 2003-13.

    Science.gov (United States)

    Knight, Marian; Nair, Manisha; Brocklehurst, Peter; Kenyon, Sara; Neilson, James; Shakespeare, Judy; Tuffnell, Derek; Kurinczuk, Jennifer J

    2016-07-20

    The causes of maternal death are now classified internationally according to ICD-MM. One significant change with the introduction of ICD-MM in 2012 was the reclassification of maternal suicide from the indirect group to the direct group. This has led to concerns about the impact of this reclassification on calculated mortality rates. The aim of this analysis was to examine the trends in maternal deaths in the UK over the past 10 years, and to investigate the impact of reclassification using ICD-MM on the observed rates. Data about all maternal deaths between 2003-13 in the UK were included in this analysis. Data about maternal deaths occurring prior to 2009 were obtained from previously published reports. The deaths of women from 2009-13 during or after pregnancy were identified through the MBRRACE-UK Confidential Enquiry into Maternal Deaths. The underlying causes of maternal death were reclassified from a disease-based system to ICD-MM. Maternal mortality rates with 95 % confidence intervals were calculated using national data on the number of maternities as the denominator. Rate ratios with 95 % CI were calculated to compare the change in rates of maternal death as per ICD-MM relative to the old classification system. There was a decrease in the maternal death rate between 2003-05 and 2011-13 (rate ratio (RR) 0.65; 95 % CI 0.54-0.77 comparing 2003-5 with 2011-13; p = 0.005 for trend over time). The direct maternal death rate calculated using the old classification decreased with a RR of 0.47 (95 % CI 0.34-0.63) when comparing 2011-13 with 2003-05; p = 0.005 for trend over time. Reclassification using ICD-MM made little material difference to the observed trend in direct maternal death rates, RR = 0.51 (95 % CI 0.39-0.68) when comparing 2003-5 with 2011-13; p = 0.005 for trend over time. The impact of reclassifying maternal deaths according to ICD-MM in the UK was minimal. However, such reclassification raises awareness of maternal suicides

  6. An analysis of observer-rated functional vision in patients implanted with the Argus II Retinal Prosthesis System at three years.

    Science.gov (United States)

    Geruschat, Duane R; Richards, Thomas P; Arditi, Aries; da Cruz, Lyndon; Dagnelie, Gislin; Dorn, Jessy D; Duncan, Jacque L; Ho, Allen C; Olmos de Koo, Lisa C; Sahel, José-Alain; Stanga, Paulo E; Thumann, Gabriele; Wang, Vizhong; Greenberg, Robert J

    2016-05-01

    The purpose of this analysis was to compare observer-rated tasks in patients implanted with the Argus II Retinal Prosthesis System, when the device is ON versus OFF. The Functional Low-Vision Observer Rated Assessment (FLORA) instrument was administered to 26 blind patients implanted with the Argus II Retinal Prosthesis System at a mean follow-up of 36 months. FLORA is a multi-component instrument that consists in part of observer-rated assessment of 35 tasks completed with the device ON versus OFF. The ease with which a patient completes a task is scored using a four-point scale, ranging from easy (score of 1) to impossible (score of 4). The tasks are evaluated individually and organised into four discrete domains, including 'Visual orientation', 'Visual mobility', 'Daily life and 'Interaction with others'. Twenty-six patients completed each of the 35 tasks. Overall, 24 out of 35 tasks (69 per cent) were statistically significantly easier to achieve with the device ON versus OFF. In each of the four domains, patients' performances were significantly better (p vision-related tasks with the device ON versus OFF. © 2016 The Authors Clinical and Experimental Optometry published by John Wiley & Sons Australia, Ltd on behalf of Optometry Australia.

  7. Attrition Bias in Panel Data: A Sheep in Wolf's Clothing? A Case Study Based on the Mabel Survey.

    Science.gov (United States)

    Cheng, Terence C; Trivedi, Pravin K

    2015-09-01

    This paper investigates the nature and consequences of sample attrition in a unique longitudinal survey of medical doctors. We describe the patterns of non-response and examine if attrition affects the econometric analysis of medical labour market outcomes using the estimation of physician earnings equations as a case study. We compare the econometric gestimates obtained from a number of different modelling strategies, which are as follows: balanced versus unbalanced samples; an attrition model for panel data based on the classic sample selection model; and a recently developed copula-based selection model. Descriptive evidence shows that doctors who work longer hours, have lower years of experience, are overseas trained and have changed their work location are more likely to drop out. Our analysis suggests that the impact of attrition on inference about the earnings of general practitioners is small. For specialists, there appears to be some evidence for an economically significant bias. Finally, we discuss how the top-up samples in the Medicine in Australia: Balancing Employment and Life survey can be used to address the problem of panel attrition. Copyright © 2015 John Wiley & Sons, Ltd.

  8. Using high sampling rate (10/20 Hz) altimeter data for the observation of coastal surface currents: A case study over the northwestern Mediterranean Sea

    Science.gov (United States)

    Birol, Florence; Delebecque, Caroline

    2014-01-01

    Satellite altimetry, measuring sea surface heights (SSHs), has unique capabilities to provide information about the ocean dynamics. In this paper, the skill of the original full rate (10/20 Hz) measurements, relative to conventional 1-Hz data, is evaluated in the context of coastal studies in the Northwestern Mediterranean Sea. The performance and the question of the measurement noise are quantified through a comparison with different tide gauge sea level time series. By applying a specific processing, closer than 30 km to the land, the number of valid data is higher for the 10/20-Hz than for the 1-Hz observations: + 4.5% for T/P, + 10.3 for Jason-1 and + 13% for Jason-2. By filtering higher sampling rate measurements (using a 30-km cut-off low-pass Lanczos filter), we can obtain the same level of sea level accuracy as we would using the classical 1-Hz altimeter data. The gain in near-shore data results in a better observation of the Liguro-Provençal-Catalan Current. The seasonal evolution of the currents derived from 20-Hz data is globally consistent with patterns derived from the corresponding 1-Hz observations. But the use of higher frequency altimeter measurements allows us to observe the variability of the regional flow closer to the coast (~ 10-15 km from land).

  9. INTRA- AND INTER-OBSERVER RELIABILITY IN SELECTION OF THE HEART RATE DEFLECTION POINT DURING INCREMENTAL EXERCISE: COMPARISON TO A COMPUTER-GENERATED DEFLECTION POINT

    Directory of Open Access Journals (Sweden)

    Bridget A. Duoos

    2002-12-01

    Full Text Available This study was designed to 1 determine the relative frequency of occurrence of a heart rate deflection point (HRDP, when compared to a linear relationship, during progressive exercise, 2 measure the reproducibility of a visual assessment of a heart rate deflection point (HRDP, both within and between observers 3 compare visual and computer-assessed deflection points. Subjects consisted of 73 competitive male cyclists with mean age of 31.4 ± 6.3 years, mean height 178.3 ± 4.8 cm. and weight 74.0 ± 4.4 kg. Tests were conducted on an electrically-braked cycle ergometer beginning at 25 watts and progressing 25 watts per minute to fatigue. Heart Rates were recorded the last 10 seconds of each stage and at fatigue. Scatter plots of heart rate versus watts were computer-generated and given to 3 observers on two different occasions. A computer program was developed to assess if data points were best represented by a single line or two lines. The HRDP represented the intersection of the two lines. Results of this study showed that 1 computer-assessed HRDP showed that 44 of 73 subjects (60.3% had scatter plots best represented by a straight line with no HRDP 2in those subjects having HRDP, all 3 observers showed significant differences(p = 0.048, p = 0.007, p = 0.001 in reproducibility of their HRDP selection. Differences in HRDP selection were significant for two of the three comparisons between observers (p = 0.002, p = 0.305, p = 0.0003 Computer-generated HRDP was significantly different than visual HRDP for 2 of 3 observers (p = 0.0016, p = 0.513, p = 0.0001. It is concluded that 1 HRDP occurs in a minority of subjects 2 significant differences exist, both within and between observers, in selection of HRDP and 3 differences in agreement between visual and computer-generated HRDP would indicate that, when HRDP exists, it should be computer-assessed

  10. Attrition tendinitis of long head of biceps brachii in relation to humeral head osteonecrosis: case report.

    Science.gov (United States)

    Wiesler, Ethan R; Sarlikiotis, Thomas; Mavrogenis, Andreas F; Kokkalis, Zinon T

    2013-01-01

    This case report identifies a 41-year-old male patient who developed anterior shoulder pain in the setting of humeral head osteonecrosis. As a consequence of the cartilage degeneration, multiple loose bodies formed and migrated into the bicipital tendon sheath, causing attrition tendinitis, which was a feature of the clinical presentation. The patient was treated by a combination of arthroscopic glenohumeral joint debridement and open tenodesis of the biceps using a suture anchor. Follow-up revealed asymptomatic shoulder function by 18 months. This is the first report in the literature of bicipital tendinitis in the context of avascular necrosis of the shoulder.

  11. Impact of automated dispensing cabinets on medication selection and preparation error rates in an emergency department: a prospective and direct observational before-and-after study.

    Science.gov (United States)

    Fanning, Laura; Jones, Nick; Manias, Elizabeth

    2016-04-01

    The implementation of automated dispensing cabinets (ADCs) in healthcare facilities appears to be increasing, in particular within Australian hospital emergency departments (EDs). While the investment in ADCs is on the increase, no studies have specifically investigated the impacts of ADCs on medication selection and preparation error rates in EDs. Our aim was to assess the impact of ADCs on medication selection and preparation error rates in an ED of a tertiary teaching hospital. Pre intervention and post intervention study involving direct observations of nurses completing medication selection and preparation activities before and after the implementation of ADCs in the original and new emergency departments within a 377-bed tertiary teaching hospital in Australia. Medication selection and preparation error rates were calculated and compared between these two periods. Secondary end points included the impact on medication error type and severity. A total of 2087 medication selection and preparations were observed among 808 patients pre and post intervention. Implementation of ADCs in the new ED resulted in a 64.7% (1.96% versus 0.69%, respectively, P = 0.017) reduction in medication selection and preparation errors. All medication error types were reduced in the post intervention study period. There was an insignificant impact on medication error severity as all errors detected were categorised as minor. The implementation of ADCs could reduce medication selection and preparation errors and improve medication safety in an ED setting. © 2015 John Wiley & Sons, Ltd.

  12. Co2(nu2)-o Quenching Rate Coefficient Derived from Coincidental SABER-TIMED and Fort Collins Lidar Observations of the Mesosphere and Lower Thermosphere

    Science.gov (United States)

    Feofilov, A. G.; Kutepov, A. A.; She, C.-Y.; Smith, A. K.; Pesnell, W. D.; Goldberg, R. A.

    2012-01-01

    Among the processes governing the energy balance in the mesosphere and lower thermosphere (MLT), the quenching of CO2(nu2) vibrational levels by collisions with O atoms plays an important role. However, there is a factor of 3-4 discrepancy between the laboratory measurements of the CO2-O quenching rate coefficient, k(sub VT),and its value estimated from the atmospheric observations. In this study, we retrieve k(sub VT) in the altitude region85-105 km from the coincident SABER/TIMED and Fort Collins sodium lidar observations by minimizing the difference between measured and simulated broadband limb 15 micron radiation. The averaged k(sub VT) value obtained in this work is 6.5 +/- 1.5 X 10(exp -12) cubic cm/s that is close to other estimates of this coefficient from the atmospheric observations.However, the retrieved k(sub VT) also shows altitude dependence and varies from 5.5 1 +/-1 10(exp -12) cubic cm/s at 90 km to 7.9 +/- 1.2 10(exp -12) cubic cm/s at 105 km. Obtained results demonstrate the deficiency in current non-LTE modeling of the atmospheric 15 micron radiation, based on the application of the CO2-O quenching and excitation rates, which are linked by the detailed balance relation. We discuss the possible model improvements, among them accounting for the interaction of the non-thermal oxygen atoms with CO2 molecules.

  13. Identification of cognitive and non-cognitive predictive variables related to attrition in baccalaureate nursing education programs in Mississippi

    Science.gov (United States)

    Hayes, Catherine

    2005-07-01

    This study sought to identify a variable or variables predictive of attrition among baccalaureate nursing students. The study was quantitative in design and multivariate correlational statistics and discriminant statistical analysis were used to identify a model for prediction of attrition. The analysis then weighted variables according to their predictive value to determine the most parsimonious model with the greatest predictive value. Three public university nursing education programs in Mississippi offering a Bachelors Degree in Nursing were selected for the study. The population consisted of students accepted and enrolled in these three programs for the years 2001 and 2002 and graduating in the years 2003 and 2004 (N = 195). The categorical dependent variable was attrition (includes academic failure or withdrawal) from the program of nursing education. The ten independent variables selected for the study and considered to have possible predictive value were: Grade Point Average for Pre-requisite Course Work; ACT Composite Score, ACT Reading Subscore, and ACT Mathematics Subscore; Letter Grades in the Courses: Anatomy & Physiology and Lab I, Algebra I, English I (101), Chemistry & Lab I, and Microbiology & Lab I; and Number of Institutions Attended (Universities, Colleges, Junior Colleges or Community Colleges). Descriptive analysis was performed and the means of each of the ten independent variables was compared for students who attrited and those who were retained in the population. The discriminant statistical analysis performed created a matrix using the ten variable model that was able to correctly predicted attrition in the study's population in 77.6% of the cases. Variables were then combined and recombined to produce the most efficient and parsimonious model for prediction. A six variable model resulted which weighted each variable according to predictive value: GPA for Prerequisite Coursework, ACT Composite, English I, Chemistry & Lab I, Microbiology

  14. SUPPLEMENT: “THE RATE OF BINARY BLACK HOLE MERGERS INFERRED FROM ADVANCED LIGO OBSERVATIONS SURROUNDING GW150914” (2016, ApJL, 833, L1)

    Energy Technology Data Exchange (ETDEWEB)

    Abbott, B. P.; Abbott, R.; Abernathy, M. R.; Adhikari, R. X. [LIGO, California Institute of Technology, Pasadena, CA 91125 (United States); Abbott, T. D. [Louisiana State University, Baton Rouge, LA 70803 (United States); Acernese, F.; Addesso, P. [Università di Salerno, Fisciano, I-84084 Salerno (Italy); Ackley, K. [University of Florida, Gainesville, FL 32611 (United States); Adams, C. [LIGO Livingston Observatory, Livingston, LA 70754 (United States); Adams, T. [Laboratoire d’Annecy-le-Vieux de Physique des Particules (LAPP), Université Savoie Mont Blanc, CNRS/IN2P3, F-74941 Annecy-le-Vieux (France); Adya, V. B.; Affeldt, C.; Allen, B. [Albert-Einstein-Institut, Max-Planck-Institut für Gravitationsphysik, D-30167 Hannover (Germany); Agathos, M.; Agatsuma, K. [Nikhef, Science Park, 1098 XG Amsterdam (Netherlands); Aggarwal, N. [LIGO, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Aguiar, O. D. [Instituto Nacional de Pesquisas Espaciais, 12227-010 São José dos Campos, São Paulo (Brazil); Aiello, L. [INFN, Gran Sasso Science Institute, I-67100 L’Aquila (Italy); Ain, A. [Inter-University Centre for Astronomy and Astrophysics, Pune 411007 (India); Ajith, P. [International Centre for Theoretical Sciences, Tata Institute of Fundamental Research, Bangalore 560012 (India); Collaboration: LIGO Scientific Collaboration and Virgo Collaboration; and others

    2016-12-01

    This article provides supplemental information for a Letter reporting the rate of (BBH) coalescences inferred from 16 days of coincident Advanced LIGO observations surrounding the transient (GW) signal GW150914. In that work we reported various rate estimates whose 90% confidence intervals fell in the range 2–600 Gpc{sup −3} yr{sup −1}. Here we give details on our method and computations, including information about our search pipelines, a derivation of our likelihood function for the analysis, a description of the astrophysical search trigger distribution expected from merging BBHs, details on our computational methods, a description of the effects and our model for calibration uncertainty, and an analytic method for estimating our detector sensitivity, which is calibrated to our measurements.

  15. An Investigation of the Kinematic and Microphysical Control of Lightning Rate, Extent and NOX Production using DC3 Observations and the NASA Lightning Nitrogen Oxides Model (LNOM)

    Science.gov (United States)

    Carey, L. D.; Koshak, W. J.; Peterson, H. S.; Matthee, R.; Bain, A. L.

    2013-12-01

    The Deep Convective Clouds and Chemistry (DC3) experiment seeks to quantify the relationship between storm physics, lightning characteristics and the production of nitrogen oxides via lightning (LNOX). The focus of this study is to investigate the kinematic and microphysical control of lightning properties, particularly those that may govern LNOX production, such as flash rate, type and extent across Alabama during DC3. Prior studies have demonstrated that lightning flash rate and type is correlated to kinematic and microphysical properties in the mixed-phase region of thunderstorms such as updraft volume and graupel mass. More study is required to generalize these relationships in a wide variety of storm modes and meteorological conditions. Less is known about the co-evolving relationship between storm physics, morphology and three-dimensional flash extent, despite its importance for LNOX production. To address this conceptual gap, the NASA Lightning Nitrogen Oxides Model (LNOM) is applied to North Alabama Lightning Mapping Array (NALMA) and Vaisala National Lightning Detection NetworkTM (NLDN) observations following ordinary convective cells through their lifecycle. LNOM provides estimates of flash rate, flash type, channel length distributions, lightning segment altitude distributions (SADs) and lightning NOX production profiles. For this study, LNOM is applied in a Lagrangian sense to multicell thunderstorms over Northern Alabama on two days during DC3 (21 May and 11 June 2012) in which aircraft observations of NOX are available for comparison. The LNOM lightning characteristics and LNOX production estimates are compared to the evolution of updraft and precipitation properties inferred from dual-Doppler and polarimetric radar analyses applied to observations from a nearby radar network, including the UAH Advanced Radar for Meteorological and Operational Research (ARMOR). Given complex multicell evolution, particular attention is paid to storm morphology, cell

  16. An Investigation of the Kinematic and Microphysical Control of Lightning Rate, Extent and NOx Production using DC3 Observations and the NASA Lightning Nitrogen Oxides Model (LNOM)

    Science.gov (United States)

    Carey, Lawrence; Koshak, William; Peterson, Harold; Matthee, Retha; Bain, Lamont

    2013-01-01

    The Deep Convective Clouds and Chemistry (DC3) experiment seeks to quantify the relationship between storm physics, lightning characteristics and the production of nitrogen oxides via lightning (LNOx). The focus of this study is to investigate the kinematic and microphysical control of lightning properties, particularly those that may govern LNOx production, such as flash rate, type and extent across Alabama during DC3. Prior studies have demonstrated that lightning flash rate and type is correlated to kinematic and microphysical properties in the mixed-phase region of thunderstorms such as updraft volume and graupel mass. More study is required to generalize these relationships in a wide variety of storm modes and meteorological conditions. Less is known about the co-evolving relationship between storm physics, morphology and three-dimensional flash extent, despite its importance for LNOx production. To address this conceptual gap, the NASA Lightning Nitrogen Oxides Model (LNOM) is applied to North Alabama Lightning Mapping Array (NALMA) and Vaisala National Lightning Detection Network(TM) (NLDN) observations following ordinary convective cells through their lifecycle. LNOM provides estimates of flash rate, flash type, channel length distributions, lightning segment altitude distributions (SADs) and lightning NOx production profiles. For this study, LNOM is applied in a Lagrangian sense to multicell thunderstorms over Northern Alabama on two days during DC3 (21 May and 11 June 2012) in which aircraft observations of NOx are available for comparison. The LNOM lightning characteristics and LNOX production estimates are compared to the evolution of updraft and precipitation properties inferred from dual-Doppler and polarimetric radar analyses applied to observations from a nearby radar network, including the UAH Advanced Radar for Meteorological and Operational Research (ARMOR). Given complex multicell evolution, particular attention is paid to storm morphology, cell

  17. Clinical correlates of weight loss and attrition during a 10-week dietary intervention study

    DEFF Research Database (Denmark)

    Handjieva-Darlenska, Teodora; Holst, Claus; Grau, Katrine

    2012-01-01

    clinical centres in 7 European countries, who underwent a 10-week dietary intervention study comparing two hypo-energetic (-600 kcal/day) diets varying in fat content. Results: The multiple regression model showed that weight loss at week 10 was predicted by: 6.55 + 1.27 × early weight loss (kg) at week 1...... kg weight loss at week 5 emerged as an optimal predictor for reaching at least 10% weight loss at week 10. Greater attrition likelihood was predicted by high-fat diet, decreased early and half-way weight losses. Conclusion: Early and half-way weight losses are associated with and could contribute......Objective: The aim of this study was to identify the pre-treatment subject characteristics and weight loss changes as determinants of weight loss and attrition during a 10-week dietary intervention study. Methods: A total of 771 obese subjects (BMI 35.6 kg/m(2)) of both genders were included from 8...

  18. Vocation, friendship and resilience: a study exploring nursing student and staff views on retention and attrition.

    Science.gov (United States)

    Williamson, Graham R; Health, Val; Proctor-Childs, Tracey

    2013-01-01

    There is international concern about retention of student nurses on undergraduate programmes. United Kingdom Higher Education Institutions are monitored on their attrition statistics and can be penalised financially, so they have an incentive to help students remain on their programmes beyond their moral duty to ensure students receive the best possible educational experience. to understand students' and staff concerns about programmes and placements as part of developing our retention strategies. This study reports qualitative data on retention and attrition collected as part of an action research study. One University School of Nursing and Midwifery in the South West of England. Staff, current third year and ex-student nurses from the adult field. Data were collected in focus groups, both face-to face and virtual, and individual telephone interviews. These were transcribed and subjected to qualitative content analysis. FOUR THEMES EMERGED: Academic support, Placements and mentors, Stresses and the reality of nursing life, and Dreams for a better programme. The themes Academic support, Placements and mentors and Stresses and the reality of nursing life, resonate with international literature. Dreams for a better programme included smaller group learning. Vocation, friendship and resilience seem instrumental in retaining students, and Higher Education Institutions should work to facilitate these. 'Vocation' has been overlooked in the retention discussions, and working more actively to foster vocation and belongingness could be important.

  19. The Flip Side of the Attrition Coin: Faculty Perceptions of Factors Supporting Graduate Student Success

    Directory of Open Access Journals (Sweden)

    Joanna A Gilmore

    2016-12-01

    Full Text Available Doctoral attrition consistently hovers around 50% with relevant literature identifying several mediating factors, including departmental culture, student demographics, and funding. To advance this literature, we interviewed 38 graduate faculty advisors in science, engineering, or mathematics disciplines at a research-extensive university to capture their perceptions of factors supporting graduate student success. Using a constant-comparison method, we found that faculty perceptions aligned within three major categories, termed: motivated student behaviors, formative student learning experiences, and essential student knowledge and skills. Student motivation was most prominently represented in findings. This aligns with prior studies showing that faculty tend to identify the cause of graduate student failure as lying within the students themselves and rarely discuss their role or the department’s contribution to attrition. Thus findings offer an opportunity to reflect and improve upon practice. The study also highlights actions graduate students can take to increase success, such as developing collegial relationships and early involvement in research and scholarly writing. We encourage graduate faculty advisors and others to identify ways to help graduate students overcome common obstacles to enduring and succeeding within graduate programs. Faculty perceptions are also examined by discipline and faculty rank, and directions for future research are offered.

  20. Attrition in Chronic Disease Self-Management Programs and self-efficacy at enrollment.

    Science.gov (United States)

    Verevkina, Nina; Shi, Yunfeng; Fuentes-Caceres, Veronica Alejandra; Scanlon, Dennis Patrick

    2014-12-01

    Among other goals, the Chronic Disease Self-Management Program (CDSMP) is designed to improve self-efficacy of the chronically ill. However, a substantial proportion of the enrollees often leave CDSMPs before completing the program curriculum. This study examines factors associated with program attrition in a CDSMP implemented in a community setting. We used data from the Our Pathways to Health program, implemented in Humboldt County, California, from 2008 to 2011. Our conceptual framework is based on Bandura's self-efficacy theory, and we used logistic regression to investigate whether baseline self-efficacy and other members' efficacy are associated with participants dropping out of the CDSMP. Twenty-three percent of the participants did not complete the program similar to previous studies. Lower baseline self-efficacy increased the odds of dropout, but other members' efficacy was not associated with differential odds of dropout. Age, educational difference between the individual and the group, weekday sessions, and social/role activity limitations are also found to be associated with program attrition. Our results suggest that participants with low starting self-efficacy may need extra help to complete the program. Further research is needed to understand how to effectively provide additional support to this group. © 2014 Society for Public Health Education.

  1. Explaining attrition and decreased effectiveness of experienced teachers: A research synthesis.

    Science.gov (United States)

    Torenbeek, Marjolein; Peters, Velibor

    2017-01-01

    Teacher retention and development of the full potential of teachers is important at a national level in order to be able to belong to the top world economies. A number of studies suggests that part of the group of experienced teachers with more than 20 years of experience perform didactically at a lower level than would be expected and are at a greater risk for attrition. The aim of the present study is to find explanations for this by making use of the Job Demands Resources Model. Specific demands of the teaching profession, interpersonal demands related to the developmental stage of experienced teachers, job resources and personal resources in relation to health and motivation are explored by reviewing a vast amount of literature. The proposed conceptual model is an extension of the Job Demands Resources Model with the inclusion of personal demands related to adulthood and personal resources. The resulting model provides us with clues on how attrition and decreased performance could be counteracted.

  2. Faculty Promotion and Attrition: The Importance of Coauthor Network Reach at an Academic Medical Center.

    Science.gov (United States)

    Warner, Erica T; Carapinha, René; Weber, Griffin M; Hill, Emorcia V; Reede, Joan Y

    2016-01-01

    Business literature has demonstrated the importance of networking and connections in career advancement. This is a little-studied area in academic medicine. To examine predictors of intra-organizational connections, as measured by network reach (the number of first- and second-degree coauthors), and their association with probability of promotion and attrition. Prospective cohort study between 2008 and 2012. Academic medical center. A total of 5787 Harvard Medical School (HMS) faculty with a rank of assistant professor or full-time instructor as of January 1, 2008. Using negative binomial models, multivariable-adjusted predictors of continuous network reach were assessed according to rank. Poisson regression was used to compute relative risk (RR) and 95 % confidence intervals (CI) for the association between network reach (in four categories) and two outcomes: promotion or attrition. Models were adjusted for demographic, professional and productivity metrics. Network reach was positively associated with number of first-, last- and middle-author publications and h-index. Among assistant professors, men and whites had greater network reach than women and underrepresented minorities (p advancement and retention in academic medicine. They can and should be investigated at other institutions.

  3. Sex offender risk assessment: the need to place recidivism research in the context of attrition in the criminal justice system.

    Science.gov (United States)

    Larcombe, Wendy

    2012-04-01

    Jurisdictions in the United States, United Kingdom, and Australia now have laws that enable preventive detention of post-sentence sex offenders based on an assessment of the offender's likely recidivism. Measures of recidivism, or risk assessments, rely on the criminal justice process to produce the "pool" of sex offenders studied. This article argues that recidivism research needs to be placed in the context of attrition studies that document the disproportionate and patterned attrition of sexual offenses and sexual offenders from the criminal justice process. Understanding the common biases that affect criminal prosecution of sex offenses would improve sexual violence prevention policies.

  4. First Language Attrition Induces Changes in Online Morphosyntactic Processing and Re-Analysis: An ERP Study of Number Agreement in Complex Italian Sentences

    Science.gov (United States)

    Kasparian, Kristina; Vespignani, Francesco; Steinhauer, Karsten

    2017-01-01

    First language (L1) attrition in adulthood offers new insight on neuroplasticity and the role of language experience in shaping neurocognitive responses to language. Attriters are multilinguals for whom advancing L2 proficiency comes at the cost of the L1, as they experience a shift in exposure and dominance (e.g., due to immigration). To date,…

  5. Taking into account the impact of attrition on the assessment of response shift and true change: a multigroup structural equation modeling approach

    NARCIS (Netherlands)

    Verdam, M.G.E.; Oort, F.J.; van der Linden, Y.M.; Sprangers, M.A.G.

    2015-01-01

    Purpose: Missing data due to attrition present a challenge for the assessment and interpretation of change and response shift in HRQL outcomes. The objective was to handle such missingness and to assess response shift and ‘true change’ with the use of an attrition-based multigroup structural

  6. Taking into account the impact of attrition on the assessment of response shift and true change: a multigroup structural equation modeling approach

    NARCIS (Netherlands)

    Verdam, Mathilde G. E.; Oort, Frans J.; van der Linden, Yvette M.; Sprangers, Mirjam A. G.

    2015-01-01

    Missing data due to attrition present a challenge for the assessment and interpretation of change and response shift in HRQL outcomes. The objective was to handle such missingness and to assess response shift and 'true change' with the use of an attrition-based multigroup structural equation

  7. Observations of C-Band Brightness Temperature and Ocean Surface Wind Speed and Rain Rate in Hurricanes Earl And Karl (2010)

    Science.gov (United States)

    Miller, Timothy; James, Mark; Roberts, Brent J.; Biswax, Sayak; Uhlhorn, Eric; Black, Peter; Linwood Jones, W.; Johnson, Jimmy; Farrar, Spencer; Sahawneh, Saleem

    2012-01-01

    Ocean surface emission is affected by: a) Sea surface temperature. b) Wind speed (foam fraction). c) Salinity After production of calibrated Tb fields, geophysical fields wind speed and rain rate (or column) are retrieved. HIRAD utilizes NASA Instrument Incubator Technology: a) Provides unique observations of sea surface wind, temp and rain b) Advances understanding & prediction of hurricane intensity c) Expands Stepped Frequency Microwave Radiometer capabilities d) Uses synthetic thinned array and RFI mitigation technology of Lightweight Rain Radiometer (NASA Instrument Incubator) Passive Microwave C-Band Radiometer with Freq: 4, 5, 6 & 6.6 GHz: a) Version 1: H-pol for ocean wind speed, b) Version 2: dual ]pol for ocean wind vectors. Performance Characteristics: a) Earth Incidence angle: 0deg - 60deg, b) Spatial Resolution: 2-5 km, c) Swath: approx.70 km for 20 km altitude. Observational Goals: WS 10 - >85 m/s RR 5 - > 100 mm/hr.

  8. Tackle-related injury rates and nature of injuries in South African Youth Week tournament rugby union players (under-13 to under-18): an observational cohort study.

    Science.gov (United States)

    Burger, Nicholas; Lambert, Mike I; Viljoen, Wayne; Brown, James C; Readhead, Clint; Hendricks, Sharief

    2014-08-12

    The tackle situation is most often associated with the high injury rates in rugby union. Tackle injury epidemiology in rugby union has previously been focused on senior cohorts but less is known about younger cohorts. The aim of this study was to report on the nature and rates of tackle-related injuries in South African youth rugby union players representing their provinces at national tournaments. Observational cohort study. Four South African Youth Week tournaments (under-13 Craven Week, under-16 Grant Khomo Week, under-18 Academy Week, under-18 Craven Week). Injury data were collected from 3652 youth rugby union players (population at risk) in 2011 and 2012. Tackle-related injury severity ('time-loss' and 'medical attention'), type and location, injury rate per 1000 h (including 95% CIs). Injury rate ratios (IRR) were calculated and modelled using a Poisson regression. A χ(2) analysis was used to detect linear trends between injuries and increasing match quarters. The 2012 under-13 Craven Week had a significantly greater 'time-loss' injury rate when compared with the 2012 under-18 Academy Week (IRR=4.43; 95% CI 2.13 to 9.21, p<0.05) and under-18 Craven Week (IRR=3.52; 95% CI 1.54 to 8.00, p<0.05). The Poisson regression also revealed a higher probability of 'overall' ('time-loss' and 'medical attention' combined) and 'time-loss' tackle-related injuries occurring at the under-13 Craven Week. The proportion of 'overall' and 'time-loss' injuries increased significantly with each quarter of the match when all four tournaments were combined (p<0.05). There was a difference in the tackle-related injury rate between the under-13 tournament and the two under-18 tournaments, and the tackle-related injury rate was higher in the final quarter of matches. Ongoing injury surveillance is required to better interpret these findings. Injury prevention strategies targeting the tackle may only be effective once the rate and nature of injuries have been accurately determined

  9. Tackle-related injury rates and nature of injuries in South African Youth Week tournament rugby union players (under-13 to under-18): an observational cohort study

    Science.gov (United States)

    Burger, Nicholas; Lambert, Mike I; Viljoen, Wayne; Brown, James C; Readhead, Clint; Hendricks, Sharief

    2014-01-01

    Objectives The tackle situation is most often associated with the high injury rates in rugby union. Tackle injury epidemiology in rugby union has previously been focused on senior cohorts but less is known about younger cohorts. The aim of this study was to report on the nature and rates of tackle-related injuries in South African youth rugby union players representing their provinces at national tournaments. Design Observational cohort study. Setting Four South African Youth Week tournaments (under-13 Craven Week, under-16 Grant Khomo Week, under-18 Academy Week, under-18 Craven Week). Participants Injury data were collected from 3652 youth rugby union players (population at risk) in 2011 and 2012. Outcome measures Tackle-related injury severity (‘time-loss’ and ‘medical attention’), type and location, injury rate per 1000 h (including 95% CIs). Injury rate ratios (IRR) were calculated and modelled using a Poisson regression. A χ2 analysis was used to detect linear trends between injuries and increasing match quarters. Results The 2012 under-13 Craven Week had a significantly greater ‘time-loss’ injury rate when compared with the 2012 under-18 Academy Week (IRR=4.43; 95% CI 2.13 to 9.21, p<0.05) and under-18 Craven Week (IRR=3.52; 95% CI 1.54 to 8.00, p<0.05). The Poisson regression also revealed a higher probability of ‘overall’ (‘time-loss’ and ‘medical attention’ combined) and ‘time-loss’ tackle-related injuries occurring at the under-13 Craven Week. The proportion of ‘overall’ and ‘time-loss’ injuries increased significantly with each quarter of the match when all four tournaments were combined (p<0.05). Conclusions There was a difference in the tackle-related injury rate between the under-13 tournament and the two under-18 tournaments, and the tackle-related injury rate was higher in the final quarter of matches. Ongoing injury surveillance is required to better interpret these findings. Injury prevention strategies

  10. Hurricane Imaging Radiometer (HIRAD) Observations of Brightness Temperatures and Ocean Surface Wind Speed and Rain Rate During NASA's GRIP and HS3 Campaigns

    Science.gov (United States)

    Miller, Timothy L.; James, M. W.; Roberts, J. B.; Jones, W. L.; Biswas, S.; Ruf, C. S.; Uhlhorn, E. W.; Atlas, R.; Black, P.; Albers, C.

    2012-01-01

    HIRAD flew on high-altitude aircraft over Earl and Karl during NASA s GRIP (Genesis and Rapid Intensification Processes) campaign in August - September of 2010, and plans to fly over Atlantic tropical cyclones in September of 2012 as part of the Hurricane and Severe Storm Sentinel (HS3) mission. HIRAD is a new C-band radiometer using a synthetic thinned array radiometer (STAR) technology to obtain spatial resolution of approximately 2 km, out to roughly 30 km each side of nadir. By obtaining measurements of emissions at 4, 5, 6, and 6.6 GHz, observations of ocean surface wind speed and rain rate can be retrieved. The physical retrieval technique has been used for many years by precursor instruments, including the Stepped Frequency Microwave Radiometer (SFMR), which has been flying on the NOAA and USAF hurricane reconnaissance aircraft for several years to obtain observations within a single footprint at nadir angle. Results from the flights during the GRIP and HS3 campaigns will be shown, including images of brightness temperatures, wind speed, and rain rate. Comparisons will be made with observations from other instruments on the campaigns, for which HIRAD observations are either directly comparable or are complementary. Features such as storm eye and eye-wall, location of storm wind and rain maxima, and indications of dynamical features such as the merging of a weaker outer wind/rain maximum with the main vortex may be seen in the data. Potential impacts on operational ocean surface wind analyses and on numerical weather forecasts will also be discussed.

  11. Differences in reach and attrition between Web-based and print-delivered tailored interventions among adults over 50 years of age: clustered randomized trial.

    Science.gov (United States)

    Peels, Denise Astrid; Bolman, Catherine; Golsteijn, Rianne Henrica Johanna; De Vries, Hein; Mudde, Aart Nicolaas; van Stralen, Maartje Marieke; Lechner, Lilian

    2012-12-17

    The Internet has the potential to provide large populations with individual health promotion advice at a relatively low cost. Despite the high rates of Internet access, actual reach by Web-based interventions is often disappointingly low, and differences in use between demographic subgroups are present. Furthermore, Web-based interventions often have to deal with high rates of attrition. This study aims to assess user characteristics related to participation and attrition when comparing Web-based and print-delivered tailored interventions containing similar content and thereby to provide recommendations in choosing the appropriate delivery mode for a particular target audience. We studied the distribution of a Web-based and a print-delivered version of the Active Plus intervention in a clustered randomized controlled trial (RCT). Participants were recruited via direct mailing within the participating Municipal Health Council regions and randomized to the printed or Web-based intervention by their region. Based on the answers given in a prior assessment, participants received tailored advice on 3 occasions: (1) within 2 weeks after the baseline, (2) 2 months after the baseline, and (3) within 4 months after the baseline (based on a second assessment at 3 months). The baseline (printed or Web-based) results were analyzed using ANOVA and chi-square tests to establish the differences in user characteristics between both intervention groups. We used logistic regression analyses to study the interaction between the user characteristics and the delivery mode in the prediction of dropout rate within the intervention period. The printed intervention resulted in a higher participation rate (19%) than the Web-based intervention (12%). Participants of the Web-based intervention were significantly younger (PWeb-based intervention group (53%) compared to the print-delivered intervention (39%, PWeb-based and the printed intervention was not explained by user characteristics. The

  12. A pilot investigation of the Motivation Behaviors Checklist (MBC): An observational rating scale of effort towards testing for baseline sports-concussion assessment.

    Science.gov (United States)

    Rabinowitz, Amanda R; Merritt, Victoria; Arnett, Peter A

    2016-08-01

    Baseline neuropsychological testing is commonly used in the management of sports-related concussion. However, underperformance due to poor effort could lead to invalid conclusions regarding postconcussion cognitive decline. We designed the Motivation Behaviors Checklist (MBC) as an observational rating scale to assess effort towards baseline neuropsychological testing. Here we present preliminary data in support of its reliability and validity. MBC items were generated based on the consensus of a panel of graduate students, undergraduates, and a clinical neuropsychologist who conduct neuropsychological evaluations for a sports concussion management program. A total of 261 college athletes were administered a standard neuropsychological test battery in addition to the MBC. A subset of evaluations (n= 101) was videotape and viewed by a second rater. Exploratory factor analysis (EFA) was used to refine the scale, and reliability and validity were evaluated. EFA revealed that the MBC items represent four latent factors-Complaints, Poor Focus, Psychomotor Agitation, and Impulsivity. Reliability analyses demonstrated that the MBC has good inter-rater reliability (intraclass correlation coefficient, ICC = .767) and internal consistency (α = .839). The construct validity of the MBC is supported by large correlations with examiners' ratings of effort (ρ = -.623) and medium-sized relationships with cognitive performance and self-ratings of effort (|ρ| between .263 and .345). Discriminant validity was supported by nonsignificant correlations with measures of depression and postconcussion symptoms (ρ = .056 and .082, respectively). These findings provide preliminary evidence that the MBC could be a useful adjunct to baseline neuropsychological evaluations for sports-concussion management.

  13. Field observations of regional and urban impacts on NO2, ozone, UVB, and nitrate radical production rates in the Phoenix air basin

    International Nuclear Information System (INIS)

    Gaffney, J.S.; Marley, N.A.; Drayton, P.J.; Doskey, P.V.; Kotamarthi, V.R.; Cunningham, M.M.; Baird, J.C.; Dintaman, J.; Hart, H.L.

    2002-01-01

    In the May and June of 1998, field measurements were taken at a site near the Usery Pass Recreation Area, ∼27 miles from the downtown Phoenix area, overlooking Phoenix and Mesa, Arizona. This site was selected to examine the impacts of the Phoenix urban plume on the Usery Pass Recreation Area and surrounding regions. Data were obtained for ultraviolet-B (UVB) radiation, nitrogen dioxide (NO 2 ), peroxyacetyl nitrate (PAN), ozone (O 3 ), and carbon monoxide (CO). Nocturnal plumes of NO 2 (in tens of ppb), observed near midnight, were correlated with CO and anti-correlated with O 3 . This behavior was consistent with the titration of locally generated NO by boundary layer O 3 to form the nighttime NO 2 plumes that were subsequently transported into the Usery Pass Recreation area. Nitrate radical (NO 3 ) production rates were calculated to be very high on the edges of these nocturnal plumes. Examination of O 3 and PAN data also indicates that Phoenix is being affected by long-range transport of pollutants from the Los Angeles to San Diego areas. A regional smoke episode was observed in May, accompanied by a decrease in UVB of factor of two and a decrease in O 3 and an increase in methyl chloride. Low level back trajectories and chemical evidence confirm that the smoke event originated in northern Mexico and that the reduced O 3 levels observed at Usery Pass could be partially due to reduced photolysis rates caused by carbonaceous soot aerosols transported in the smoke plume. The results are discussed with regard to potential effects of local pollution transport from the Phoenix air basin as well as an assessment of the contributions from long-range transport of pollutants to the background levels in the Phoenix-Usery Pass area. (author)

  14. Effectiveness of outpatient cognitive-behavioral therapy for adolescents under routine care conditions on behavioral and emotional problems rated by parents and patients: an observational study.

    Science.gov (United States)

    Walter, Daniel; Dachs, Lydia; Faber, Martin; Goletz, Hildegard; Goertz-Dorten, Anja; Hautmann, Christopher; Kinnen, Claudia; Rademacher, Christiane; Schuermann, Stephanie; Metternich-Kaizman, Tanja Wolff; Doepfner, Manfred

    2018-01-01

    Few studies have examined the effectiveness of outpatient cognitive-behavioral therapy (CBT) delivered in routine care settings for children and adolescents with mental disorders. This observational study examined changes in behavioral and emotional problems of adolescents with mental disorders during routine outpatient CBT delivered at a university outpatient clinic and compared them with a historical control group of youths who received academic tutoring of comparable length and intensity. Assessments were made at the start and end of treatment (pre- and post-assessment) using parent ratings of the German versions of the Child Behavior Checklist (CBCL) and self-ratings of the Youth Self-Report (YSR) scale. For the main analysis, 677 adolescents aged 11‒21 years had complete data. Changes from pre- to post-assessment showed significant reductions in mental health problems on both parent- and self-ratings. Pre- to post-effect sizes (Cohen's d) were small-to-medium for the total sample (d = 0.23 to d = 0.62) and medium-to-large for those adolescents rated in the clinical range on each (sub)scale at the start of treatment (d = 0.65 to d = 1.48). We obtained medium net effect sizes (d = 0.69) for the CBCL and YSR total scores when patients in the clinical range were compared to historical controls. However, a substantial part of the sample remained in the clinical range at treatment end. The results suggest that CBT is effective for adolescents with mental disorders when administered under routine care conditions but must be interpreted conservatively due to the lack of a direct control condition.

  15. Experimental study of microstructure changes due to low cycle fatigue of a steel nanocrystallised by Surface Mechanical Attrition Treatment (SMAT)

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Z. [ICD, P2MN, LASMIS, University of Technology of Troyes, UMR 6281, CNRS, Troyes (France); Retraint, D., E-mail: delphine.retraint@utt.fr [ICD, P2MN, LASMIS, University of Technology of Troyes, UMR 6281, CNRS, Troyes (France); Baudin, T.; Helbert, A.L.; Brisset, F. [ICMMO, Univ Paris-Sud, Université Paris-Saclay, UMR CNRS 8182, 91405 Orsay Cedex (France); Chemkhi, M.; Zhou, J. [ICD, P2MN, LASMIS, University of Technology of Troyes, UMR 6281, CNRS, Troyes (France); Kanouté, P. [ICD, P2MN, LASMIS, University of Technology of Troyes, UMR 6281, CNRS, Troyes (France); ONERA, The French Aerospace Lab, 29 avenue de la Division Leclerc, 92322 Chatillon Cedex (France)

    2017-02-15

    Electron Backscatter Diffraction technique is used to characterize the microstructure of 316L steel generated by Surface Mechanical Attrition Treatment (SMAT) before and after low cycle fatigue tests. A grain size gradient is generated from the top surface to the interior of the samples after SMAT so that three main regions can be distinguished below the treated surface: (i) the ultra-fine grain area within 5 μm under the top surface with preferably oriented grains, (ii) the intermediate area where the original grains are partially transformed, and (iii) the edge periphery area where the original grains are just mechanically deformed with the presence of plastic slips. Fatigue tests show that cyclic loading does not change the grain orientation spread and does not activate any plastic slip in the ultra-fine grain top surface area induced by SMAT. On the opposite, in the plastically SMAT affected region including the intermediate area and the edge periphery area, new slip systems are activated by low cycle fatigue while the grain orientation spread is increased. These results represent a first very interesting step towards the characterization and understanding of mechanical mechanisms involved during the fatigue of a grain size gradient material. - Highlights: •LCF tests are carried out on specimens processed by SMAT. •EBSD is used to investigate microstructural changes induced by LCF. •A grain size gradient is generated by SMAT from surface to the bulk of the fatigue samples. •New slip systems are activated by LCF and GOS is increased in plastically deformed region. •However, these phenomena are not observed in the top surface ultra-fine grain area.

  16. Experimental study of microstructure changes due to low cycle fatigue of a steel nanocrystallised by Surface Mechanical Attrition Treatment (SMAT)

    International Nuclear Information System (INIS)

    Sun, Z.; Retraint, D.; Baudin, T.; Helbert, A.L.; Brisset, F.; Chemkhi, M.; Zhou, J.; Kanouté, P.

    2017-01-01

    Electron Backscatter Diffraction technique is used to characterize the microstructure of 316L steel generated by Surface Mechanical Attrition Treatment (SMAT) before and after low cycle fatigue tests. A grain size gradient is generated from the top surface to the interior of the samples after SMAT so that three main regions can be distinguished below the treated surface: (i) the ultra-fine grain area within 5 μm under the top surface with preferably oriented grains, (ii) the intermediate area where the original grains are partially transformed, and (iii) the edge periphery area where the original grains are just mechanically deformed with the presence of plastic slips. Fatigue tests show that cyclic loading does not change the grain orientation spread and does not activate any plastic slip in the ultra-fine grain top surface area induced by SMAT. On the opposite, in the plastically SMAT affected region including the intermediate area and the edge periphery area, new slip systems are activated by low cycle fatigue while the grain orientation spread is increased. These results represent a first very interesting step towards the characterization and understanding of mechanical mechanisms involved during the fatigue of a grain size gradient material. - Highlights: •LCF tests are carried out on specimens processed by SMAT. •EBSD is used to investigate microstructural changes induced by LCF. •A grain size gradient is generated by SMAT from surface to the bulk of the fatigue samples. •New slip systems are activated by LCF and GOS is increased in plastically deformed region. •However, these phenomena are not observed in the top surface ultra-fine grain area.

  17. Improving retention and graduation rates for black students in nursing education: a developmental model.

    Science.gov (United States)

    Jones, S H

    1992-01-01

    High attrition rates among black students are a significant factor in the decline in graduation rates from nursing programs. Nursing education needs a program to address problems of anger, frustration, and loneliness and to develop the black student as a whole person.

  18. Multi-GNSS high-rate RTK, PPP and novel direct phase observation processing method: application to precise dynamic displacement detection

    Science.gov (United States)

    Paziewski, Jacek; Sieradzki, Rafal; Baryla, Radoslaw

    2018-03-01

    This paper provides the methodology and performance assessment of multi-GNSS signal processing for the detection of small-scale high-rate dynamic displacements. For this purpose, we used methods of relative (RTK) and absolute positioning (PPP), and a novel direct signal processing approach. The first two methods are recognized as providing accurate information on position in many navigation and surveying applications. The latter is an innovative method for dynamic displacement determination with the use of GNSS phase signal processing. This method is based on the developed functional model with parametrized epoch-wise topocentric relative coordinates derived from filtered GNSS observations. Current regular kinematic PPP positioning, as well as medium/long range RTK, may not offer coordinate estimates with subcentimeter precision. Thus, extended processing strategies of absolute and relative GNSS positioning have been developed and applied for displacement detection. The study also aimed to comparatively analyze the developed methods as well as to analyze the impact of combined GPS and BDS processing and the dependence of the results of the relative methods on the baseline length. All the methods were implemented with in-house developed software allowing for high-rate precise GNSS positioning and signal processing. The phase and pseudorange observations collected with a rate of 50 Hz during the field test served as the experiment’s data set. The displacements at the rover station were triggered in the horizontal plane using a device which was designed and constructed to ensure a periodic motion of GNSS antenna with an amplitude of ~3 cm and a frequency of ~4.5 Hz. Finally, a medium range RTK, PPP, and direct phase observation processing method demonstrated the capability of providing reliable and consistent results with the precision of the determined dynamic displacements at the millimeter level. Specifically, the research shows that the standard deviation of

  19. Effects of Low- Versus High-Fidelity Simulations on the Cognitive Burden and Performance of Entry-Level Paramedicine Students: A Mixed-Methods Comparison Trial Using Eye-Tracking, Continuous Heart Rate, Difficulty Rating Scales, Video Observation and Interviews.

    Science.gov (United States)

    Mills, Brennen W; Carter, Owen B-J; Rudd, Cobie J; Claxton, Louise A; Ross, Nathan P; Strobel, Natalie A

    2016-02-01

    High-fidelity simulation-based training is often avoided for early-stage students because of the assumption that while practicing newly learned skills, they are ill suited to processing multiple demands, which can lead to "cognitive overload" and poorer learning outcomes. We tested this assumption using a mixed-methods experimental design manipulating psychological immersion. Thirty-nine randomly assigned first-year paramedicine students completed low- or high-environmental fidelity simulations [low-environmental fidelity simulations (LF(en)S) vs. high-environmental fidelity simulation (HF(en)S)] involving a manikin with obstructed airway (SimMan3G). Psychological immersion and cognitive burden were determined via continuous heart rate, eye tracking, self-report questionnaire (National Aeronautics and Space Administration Task Load Index), independent observation, and postsimulation interviews. Performance was assessed by successful location of obstruction and time-to-termination. Eye tracking confirmed that students attended to multiple, concurrent stimuli in HF(en)S and interviews consistently suggested that they experienced greater psychological immersion and cognitive burden than their LF(en)S counterparts. This was confirmed by significantly higher mean heart rate (P cognitive burden but this has considerable educational merit.

  20. Surface mechanical attrition treatment induced phase transformation behavior in NiTi shape memory alloy

    International Nuclear Information System (INIS)

    Hu, T.; Wen, C.S.; Lu, J.; Wu, S.L.; Xin, Y.C.; Zhang, W.J.; Chu, C.L.; Chung, J.C.Y.; Yeung, K.W.K.; Kwok, D.T.K.; Chu, Paul K.

    2009-01-01

    The phase constituents and transformation behavior of the martensite B19' NiTi shape memory alloy after undergoing surface mechanical attrition treatment (SMAT) are investigated. SMAT is found to induce the formation of a parent B2 phase from the martensite B19' in the top surface layer. By removing the surface layer-by-layer, X-ray diffraction reveals that the amount of the B2 phase decreases with depth. Differential scanning calorimetry (DSC) further indicates that the deformed martensite in the sub-surface layer up to 300 μm deep exhibits the martensite stabilization effect. The graded phase structure and transformation behavior in the SMATed NiTi specimen can be attributed to the gradient change in strain with depth.

  1. Production of fines during co-combustion of coal with biomass fuels by fragmentation and attrition

    Energy Technology Data Exchange (ETDEWEB)

    I. Gulyurtlu; D. Boavida; H. Lopes (and others) [DEECA-INETI, Lisbon (Portugal)

    2005-07-01

    Results are reported from a project funded by the RFCS Programme of the European Union. The aim is to investigate, experimentally and by modeling, the production of fine char and ash particles during co-combustion of coal with wastes and biofuels in circulating fluidized bed. Work was undertaken at installations of different scales. Polish and Colombian coals were base fuels. The additional fuels were two sewage sludges. Bed temperature, feeding system, sand particle size, devolatilisation behaviour and char burn-out were studied to verify their influence on the fine particle production. Modeling was also carried out to understand the mechanisms of fragmentation and attrition. Samples from bed and cyclone were collected to determine particle size distributions. 11 refs.

  2. Properties and sinterability of wet and dry attrition-milled OREOXed powder

    International Nuclear Information System (INIS)

    Lee, J. W.; Kim, J. H.; Kim, W. K.; Park, K. I.; Lee, J. W.

    2001-01-01

    The powder properties and sinterability were investigated with the powder prepared by wet and dry attrition milling of OREOX-treated powder. The OREOX-treated powder was prepared from the simulated spent fuel. Powder having less than 1 μm of average particle size could be obtained by dry milling, but not be obtained by wet milling. Thus, specific surface area of dry milled powder was higher than that of wet milled powder. With increasing of milling time, dry milled powder formed dense agglomerate while wet milled powder showed loose agglomerate. The pellets with higher than 95% T.D. of sintered density and larger than 7 μm of grain size were made with the milled powder regardless of milling method. The milling time in wet milling has greatly improved the sinterability. The pellets produced with dry milled powder have higher sintered density and larger grain size

  3. Attrition-free pyrolysis to produce bio-oil and char.

    Science.gov (United States)

    Mauviel, Guillain; Guillain, Mauviel; Kies, Fairouz; Fairouz, Kies; René, Mar Sans; Mar, Sans Rene; Ferrer, Monique; Monique, Ferrer; Lédé, Jacques; Jacques, Lédé

    2009-12-01

    Experiments are performed on a laboratory scale setup where beech wood chips are heated by gas convection and walls radiation. This study shows that it is possible to obtain high bio-oil and char yields with relatively low external heat transfer coefficients. The main advantage of this convection/radiation heat transfer mode compared to solid-solid collisions, applied in fluidized bed or twin screw reactors, is the reduction of solid attrition (char and sand). Thus tricky gas-solid separation through hot cyclones and/or hot filters could be avoided or reduced. It should be possible to recover directly bio-oil with less char particles and char free of sand dust. These qualities would allow easier use of these bio-products in different applications.

  4. Exercise Intervention: Attrition, Compliance, Adherence, and Progression Following Hematopoietic Stem Cell Transplantation
.

    Science.gov (United States)

    Peters, Tara; Erdmann, Ruby; Hacker, Eileen Danaher

    2018-02-01

    Exercise is widely touted as an effective intervention to optimize health and well-being after high-dose chemotherapy and hematopoietic stem cell transplantation. 
. This article reports attrition, compliance, adherence, and progression from the strength training arm of the single-blind randomized, controlled trial Strength Training to Enhance Early Recovery (STEER). 
. 37 patients were randomized to the intervention and participated in a structured strength training program introduced during hospitalization and continued for six weeks after release. Research staff and patients maintained exercise logs to document compliance, adherence, and progression. 
. No patients left the study because of burden. Patients were compliant with completion of exercise sessions, and their adherence was high; they also progressed on their exercise prescription. Because STEER balances intervention effectiveness with patient burden, the findings support the likelihood of successful translation into clinical practice.

  5. The turbulent life of juvenile icebergs: Observations from an array of high-rate time-lapse cameras in LeConte Bay, Alaska

    Science.gov (United States)

    Kienholz, C.; Amundson, J. M.; Jackson, R. H.; Motyka, R. J.; Nash, J. D.; Sutherland, D.

    2017-12-01

    Tidewater glacier behavior is driven by poorly understood processes occurring at the ice-ocean interface, including sedimentation and erosion, iceberg calving, and submarine melting. These processes are inherently difficult to observe, calling for innovative field techniques and numerical models. As part of a multi-year field effort to constrain ocean-glacier heat and mass exchange, we deployed an array of high-rate time-lapse cameras (sampling intervals between 15 seconds and 2 minutes) to monitor the terminus of LeConte Glacier and its proglacial fjord. The camera array has operated continuously for more than a year. Our high sampling rates enable tracking of iceberg motion with optical flow algorithms, which have been used widely in computer vision but less so in glaciology and oceanography. Such algorithms track individual features (e.g., corners of icebergs), which is ideal for iceberg-rich fjords, where motion can vary substantially over short temporal and spatial scales (e.g., due to complex surface currents or different iceberg sizes). We process our data to quantify subdaily to seasonal patterns in surface currents and relate them to forcing from tides, wind, and glacier runoff. Flow is most variable close to the glacier terminus due to frequent calving events and turbulent plume dynamics. Farther down fjord, more consistent patterns emerge, driven by tides, wind, and runoff and altered by fjord geometry. Our tracking results compare favorably to and complement our Acoustic Doppler Current Profiler measurements from boats and moorings. Given their high spatial and temporal resolution, our observations will place important surface constraints on forthcoming hydrodynamic modeling efforts. The deployment of the cameras in a harsh environment and the corresponding image processing provided an opportunity to test hardware and software thoroughly, which will prove useful for similar systems at other glaciers.

  6. New constraints on slip rates and locking depths of the San Andreas Fault System from Sentinel-1A InSAR and GAGE GPS observations

    Science.gov (United States)

    Ward, L. A.; Smith-Konter, B. R.; Higa, J. T.; Xu, X.; Tong, X.; Sandwell, D. T.

    2017-12-01

    After over a decade of operation, the EarthScope (GAGE) Facility has now accumulated a wealth of GPS and InSAR data, that when successfully integrated, make it possible to image the entire San Andreas Fault System (SAFS) with unprecedented spatial coverage and resolution. Resulting surface velocity and deformation time series products provide critical boundary conditions needed for improving our understanding of how faults are loaded across a broad range of temporal and spatial scales. Moreover, our understanding of how earthquake cycle deformation is influenced by fault zone strength and crust/mantle rheology is still developing. To further study these processes, we construct a new 4D earthquake cycle model of the SAFS representing the time-dependent 3D velocity field associated with interseismic strain accumulation, co-seismic slip, and postseismic viscoelastic relaxation. This high-resolution California statewide model, spanning the Cerro Prieto fault to the south to the Maacama fault to the north, is constructed on a 500 m spaced grid and comprises variable slip and locking depths along 42 major fault segments. Secular deep slip is prescribed from the base of the locked zone to the base of the elastic plate while episodic shallow slip is prescribed from the historical earthquake record and geologic recurrence intervals. Locking depths and slip rates for all 42 fault segments are constrained by the newest GAGE Facility geodetic observations; 3169 horizontal GPS velocity measurements, combined with over 53,000 line-of-sight (LOS) InSAR velocity observations from Sentinel-1A, are used in a weighted least-squares inversion. To assess slip rate and locking depth sensitivity of a heterogeneous rheology model, we also implement variations in crustal rigidity throughout the plate boundary, assuming a coarse representation of shear modulus variability ranging from 20-40 GPa throughout the (low rigidity) Salton Trough and Basin and Range and the (high rigidity) Central

  7. Causes of death and infant mortality rates among full-term births in the United States between 2010 and 2012: An observational study.

    Science.gov (United States)

    Bairoliya, Neha; Fink, Günther

    2018-03-01

    While the high prevalence of preterm births and its impact on infant mortality in the US have been widely acknowledged, recent data suggest that even full-term births in the US face substantially higher mortality risks compared to European countries with low infant mortality rates. In this paper, we use the most recent birth records in the US to more closely analyze the primary causes underlying mortality rates among full-term births. Linked birth and death records for the period 2010-2012 were used to identify the state- and cause-specific burden of infant mortality among full-term infants (born at 37-42 weeks of gestation). Multivariable logistic models were used to assess the extent to which state-level differences in full-term infant mortality (FTIM) were attributable to observed differences in maternal and birth characteristics. Random effects models were used to assess the relative contribution of state-level variation to FTIM. Hypothetical mortality outcomes were computed under the assumption that all states could achieve the survival rates of the best-performing states. A total of 10,175,481 infants born full-term in the US between January 1, 2010, and December 31, 2012, were analyzed. FTIM rate (FTIMR) was 2.2 per 1,000 live births overall, and ranged between 1.29 (Connecticut, 95% CI 1.08, 1.53) and 3.77 (Mississippi, 95% CI 3.39, 4.19) at the state level. Zero states reached the rates reported in the 6 low-mortality European countries analyzed (FTIMR 2.75. Sudden unexpected death in infancy (SUDI) accounted for 43% of FTIM; congenital malformations and perinatal conditions accounted for 31% and 11.3% of FTIM, respectively. The largest mortality differentials between states with good and states with poor FTIMR were found for SUDI, with particularly large risk differentials for deaths due to sudden infant death syndrome (SIDS) (odds ratio [OR] 2.52, 95% CI 1.86, 3.42) and suffocation (OR 4.40, 95% CI 3.71, 5.21). Even though these mortality differences

  8. Dreams and disappointments regarding nursing: Student nurses' reasons for attrition and retention. A qualitative study design.

    Science.gov (United States)

    Ten Hoeve, Yvonne; Castelein, Stynke; Jansen, Gerard; Roodbol, Petrie

    2017-07-01

    In the Netherlands, hundreds of students register annually for a nursing programme, but not all of these students manage to complete their training. The main aim of this study was to examine which factors affect student nurses' decision to leave or complete their programme. The study used an exploratory descriptive design, employing a qualitative phenomenological approach. Student nurses (n=17) at the beginning of their third year of the four-year Bachelor's programme. Data were collected at four Universities of Applied Sciences in the Netherlands, from December 2013 to January 2014. Semi-structured interviews were used to collect the data, using an interview guide. The main reasons for students to become nurses were the caring aspect, personal experiences with healthcare, role models in their immediate environment, and job opportunities. They had both altruistic and professional perceptions of their profession. Reasons for attrition were strongly related to the training programme and to their clinical placements, in particular the perceived lack of support from mentors and team. Feelings of being welcomed and working in a nice team proved to be more important reasons for completing the programme than the specific clinical field. Student nurses started their studies with many dreams, such as caring for people and having the opportunity to deliver excellent nursing care. When their expectations were not met, their dreams became disappointments which caused them to consider stopping and even to leave (attrition). The role of lecturers and mentors seems invaluable in protecting and guiding students through their programme and placements. Optimal cooperation between lecturers and mentors is of paramount importance to retain student nurses in their training programmes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Articulating attrition: Graduate school experiences of female doctoral students in the sciences

    Science.gov (United States)

    Osburn, Kathryn Ann

    2005-07-01

    Despite decades of research and reform efforts designed to bolster female retention in scientific disciplines, the conundrum of women's departure from doctoral programs in the sciences remains. This qualitative case study investigated the aspects of the graduate school experience that female doctoral students described as facilitating or impeding their successful degree completion in chemistry. I analyzed the graduate school narratives of twelve female participants who represented both successful and unsuccessful doctoral recipients from four advisors at one university. Participants identified four types of experiences that facilitated their retention in the doctoral program: feeling successful and confident in meeting the program requirements, having positive research experiences, receiving support from social networks, and being dedicated to career goals. Participants cited four kinds of experiences that impeded their continued participation in the doctoral program: having negative research experiences, feeling a lack of success and confidence in meeting the program requirements, changing career goals, and receiving no support from social networks. The graduate school experiences of participants who did and did not successfully attain their degree objectives differed in terms of four dimensions: pre-program experiences, academic experiences, advisory experiences, and social experiences. Based on these findings, I have proposed a model of attrition and retention that emphasizes the role that these unique program experiences play in shaping participants' sense of professional fit within the community of doctoral chemists, consequently contributing to their differential program outcomes. This study not only offers a new perspective on the phenomenon of female doctoral attrition in the sciences but also informs the development of more gender-inclusive graduate science practices and policies that will support the retention of female doctoral students.

  10. Reproducibility of the pink esthetic score--rating soft tissue esthetics around single-implant restorations with regard to dental observer specialization.

    Science.gov (United States)

    Gehrke, Peter; Lobert, Markus; Dhom, Günter

    2008-01-01

    The pink esthetic score (PES) evaluates the esthetic outcome of soft tissue around implant-supported single crowns in the anterior zone by awarding seven points for the mesial and distal papilla, soft-tissue level, soft-tissue contour, soft-tissue color, soft-tissue texture, and alveolar process deficiency. The aim of this study was to measure the reproducibility of the PES and assess the influence exerted by the examiner's degree of dental specialization. Fifteen examiners (three general dentists, three oral maxillofacial surgeons, three orthodontists, three postgraduate students in implant dentistry, and three lay people) applied the PES to 30 implant-supported single restorations twice at an interval of 4 weeks. Using a 0-1-2 scoring system, 0 being the lowest, 2 being the highest value, the maximum achievable PES was 14. At the second assessment, the photographs were scored in reverse order. Differences between the two assessments were evaluated with the Spearman's rank correlation coefficient (R). The Wilcoxon signed-rank test was used for comparisons of differences between the ratings. A significance level of p esthetic restorations showed the smallest deviations. Orthodontists were found to have assigned significantly poorer ratings than any other group. The assessment of postgraduate students and laypersons were the most favorable. The PES allows for a more objective appraisal of the esthetic short- and long-term results of various surgical and prosthetic implant procedures. It reproducibly evaluates the peri-implant soft tissue around single-implant restorations and results in good intra-examiner agreement. However, an effect of observer specialization on rating soft-tissue esthetics can be shown.

  11. Predictors of Short- and Long-Term Attrition From the Parents as Agents of Change Randomized Controlled Trial for Managing Pediatric Obesity.

    Science.gov (United States)

    Spence, Nicholas D; Newton, Amanda S; Keaschuk, Rachel A; Ambler, Kathryn A; Jetha, Mary M; Holt, Nicholas L; Rosychuk, Rhonda J; Spence, John C; Sharma, Arya M; Ball, Geoff D C

    Attrition in pediatric weight management is a substantial problem. This study examined factors associated with short- and long-term attrition from a lifestyle and behavioral intervention for parents of children with overweight or obesity. Fifty-two families with children ages 6 to 12 years old and body mass index at or above the 85th percentile participated in a randomized controlled trial focused on parents, comparing parent-based cognitive behavioral therapy with parent-based psychoeducation for pediatric weight management. We examined program attrition using two clinical phases of the intervention: short-term and long-term attrition, modeled using the general linear model. Predictors included intervention type, child/parent weight status, sociodemographic factors, and health of the family system. Higher self-assessed health of the family system was associated with lower short-term attrition; higher percentage of intervention sessions attended by parents was associated with lower long-term attrition. Different variables were significant in our short- and long-term models. Attrition might best be conceptualized based on short- and long-term phases of clinical, parent-based interventions for pediatric weight management. Copyright © 2016 National Association of Pediatric Nurse Practitioners. Published by Elsevier Inc. All rights reserved.

  12. Real-time capture of seismic waves using high-rate multi-GNSS observations: Application to the 2015 Mw 7.8 Nepal earthquake

    Science.gov (United States)

    Geng, Tao; Xie, Xin; Fang, Rongxin; Su, Xing; Zhao, Qile; Liu, Gang; Li, Heng; Shi, Chuang; Liu, Jingnan

    2016-01-01

    The variometric approach is investigated to measure real-time seismic waves induced by the 2015 Mw 7.8 Nepal earthquake with high-rate multi-GNSS observations, especially with the contribution of newly available BDS. The velocity estimation using GPS + BDS shows an additional improvement of around 20% with respect to GPS-only solutions. We also reconstruct displacements by integrating GNSS-derived velocities after a linear trend removal (IGV). The displacement waveforms with accuracy of better than 5 cm are derived when postprocessed GPS precise point positioning results are used as ground truth, even if those stations have strong ground motions and static offsets of up to 1-2 m. GNSS-derived velocity and displacement waveforms with the variometric approach are in good agreement with results from strong motion data. We therefore conclude that it is feasible to capture real-time seismic waves with multi-GNSS observations using the IGV-enhanced variometric approach, which has critical implications for earthquake early warning, tsunami forecasting, and rapid hazard assessment.

  13. Turbulent energy dissipation rates observed by Doppler MST Radar and by rocket-borne instruments during the MIDAS/MaCWAVE campaign 2002

    Directory of Open Access Journals (Sweden)

    N. Engler

    2005-06-01

    Full Text Available During the MIDAS/MaCWAVE campaign in summer 2002 we have observed turbulence using Doppler beam steering measurements obtained from the ALWIN VHF radar at Andøya/Northern Norway. This radar was operated in the Doppler beam steering mode for turbulence investigations during the campaign, as well as in spaced antenna mode, for continuously measuring the background wind field. The real-time data analysis of the Doppler radar backscattering provided the launch conditions for the sounding rockets. The spectral width data observed during the occurrence of PMSE were corrected for beam and shear broadening caused by the background wind field to obtain the turbulent part of the spectral width. The turbulent energy dissipation rates determined from the turbulent spectral width vary between 5 and 100mW kg-1 in the altitude range of 80-92km and increase with altitude. These estimations agree well with the in-situ measurements using the CONE sensor which was launched on 3 sounding rockets during the campaign.

  14. Work stress and patient safety: observer-rated work stressors as predictors of characteristics of safety-related events reported by young nurses.

    Science.gov (United States)

    Elfering, A; Semmer, N K; Grebner, S

    This study investigates the link between workplace stress and the 'non-singularity' of patient safety-related incidents in the hospital setting. Over a period of 2 working weeks 23 young nurses from 19 hospitals in Switzerland documented 314 daily stressful events using a self-observation method (pocket diaries); 62 events were related to patient safety. Familiarity of safety-related events and probability of recurrence, as indicators of non-singularity, were the dependent variables in multilevel regression analyses. Predictor variables were both situational (self-reported situational control, safety compliance) and chronic variables (job stressors such as time pressure, or concentration demands and job control). Chronic work characteristics were rated by trained observers. The most frequent safety-related stressful events included incomplete or incorrect documentation (40.3%), medication errors (near misses 21%), delays in delivery of patient care (9.7%), and violent patients (9.7%). Familiarity of events and probability of recurrence were significantly predicted by chronic job stressors and low job control in multilevel regression analyses. Job stressors and low job control were shown to be risk factors for patient safety. The results suggest that job redesign to enhance job control and decrease job stressors may be an important intervention to increase patient safety.

  15. Detection rates, trends in and factors affecting observed levels of selected volatile organic compounds in blood among US adolescents and adults.

    Science.gov (United States)

    Jain, Ram B

    2017-12-01

    Data from National Health and Nutrition Examination Survey were analyzed to evaluate detection rates, trend in and factors affecting the observed levels of 1,4-dichlorobenzene, benzene, ethylbenzene, o-xylene, styrene, toluene, and m/p-xylene among US adolescents and adults over 2005-2012. Over 2005-20102, among adolescents, detection rates declined by more than 50% for benzene, ethylbenzene, and o-xylene, and among adults, detection rates declined by more than 50% for ethylbenzene and o-xylene and by a little less than 50% for benzene. Among adults, adjusted levels of 1, 4-dichlorobenzene, benzene, ethylbenzene, o-xylene, toluene, and m/p-xylene decreased by 13.7%, 17.1%, 20%, 17.7%, 23.2%, and 18.7% respectively for every two-year survey cycle. Among adolescents, percentage decline in the levels of 1, 4-dichlorobenzene, benzene, ethylbenzene, o-xylene, styrene, toluene, and m/p-xylene was 15.2%, 21.4%, 19.3%, 16.1%, 47.8%, and 17.7% respectively for every two year survey period. The ratio of adjusted geometric means for adult smokers as compared to adult nonsmokers was 10.7 for benzene, 3.5 for ethylbenzene, 2.0 for o-xylene, 3.4 for styrene, 3.5 for toluene, and 2.2 for m/p-xylene. Among adolescents, gender did not affect the adjusted levels of any of the seven VOCs, and the order in which adjusted levels for 1, 4-dichlorobenzene by race/ethnicity was observed was: non-Hispanic white (0.038ng/mL)non-Hispanic black (0.178ng/mL) and most of the pairwise comparisons were statistically significantly different (pvs. 0.025ng/mL). For adults, gender did not affect the adjusted levels of 1, 4-dicholorobenzene, ethylbenzene, o-xylene, styrene, toluene, and m/p-xylene. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Combination of High Rate, Real-time GNSS and Accelerometer Observations - Preliminary Results Using a Shake Table and Historic Earthquake Events.

    Science.gov (United States)

    Jackson, Michael; Passmore, Paul; Zimakov, Leonid; Raczka, Jared

    2014-05-01

    One of the fundamental requirements of an Earthquake Early Warning (EEW) system (and other mission critical applications) is to quickly detect and process the information from the strong motion event, i.e. event detection and location, magnitude estimation, and the peak ground motion estimation at the defined targeted site, thus allowing the civil protection authorities to provide pre-programmed emergency response actions: Slow down or stop rapid transit trains and high-speed trains; shutoff of gas pipelines and chemical facilities; stop elevators at the nearest floor; send alarms to hospitals, schools and other civil institutions. An important question associated with the EEW system is: can we measure displacements in real time with sufficient accuracy? Scientific GNSS networks are moving towards a model of real-time data acquisition, storage integrity, and real-time position and displacement calculations. This new paradigm allows the integration of real-time, high-rate GNSS displacement information with acceleration and velocity data to create very high-rate displacement records. The mating of these two instruments allows the creation of a new, very high-rate (200 Hz) displacement observable that has the full-scale displacement characteristics of GNSS and high-precision dynamic motions of seismic technologies. It is envisioned that these new observables can be used for earthquake early warning studies and other mission critical applications, such as volcano monitoring, building, bridge and dam monitoring systems. REF TEK a Division of Trimble has developed the integrated GNSS/Accelerograph system, model 160-09SG, which consists of REF TEK's fourth generation electronics, a 147-01 high-resolution ANSS Class A accelerometer, and Trimble GNSS receiver and antenna capable of real time, on board Precise Point Positioning (PPP) techniques with satellite clock and orbit corrections delivered to the receiver directly via L-band satellite communications. The test we

  17. Incidence rate of ovarian cancer cases in Saudi Arabia: an observational descriptive epidemiological analysis of data from Saudi Cancer Registry 2001–2008

    Directory of Open Access Journals (Sweden)

    Alghamdi IG

    2014-06-01

    Full Text Available Ibrahim G Alghamdi,1,2 Issam I Hussain,1 Mohamed S Alghamdi,3 Mansour M Alghamdi,4 Ahlam A Dohal,4 Mohammed A El-Sheemy51School of Life Sciences, University of Lincoln, Brayford Pool, Lincoln, UK; 2Al-Baha University, Kingdom of Saudia Arabia; 3Ministry of Health, General Directorate of Health Affairs, Al-Baha, Kingdom of Saudi Arabia; 4King Fahad Specialist Hospital–Dammam, Kingdom of Saudi Arabia; 5Department of Research and Development, Lincoln Hospital, United Lincolnshire Hospitals, National Health Service Trust, Lincoln, UKPurpose: This study provides descriptive epidemiological data, such as the percentage of cases diagnosed, crude incidence rate (CIR, and age-standardized incidence rate (ASIR of ovarian cancer in Saudi Arabia from 2001–2008. Patients and methods: A retrospective descriptive epidemiological analysis of all ovarian cancer cases recorded in the Saudi Cancer Registry (SCR from January 2001–December 2008 was performed. The data were analyzed using descriptive statistics, analysis of variance tests, Poisson regression, and simple linear modeling.Results: A total of 991 ovarian cancer cases were recorded in the SCR from January 2001–December 2008. The region of Riyadh had the highest overall ASIR at 3.3 cases per 100,000 women, followed by the Jouf and Asir regions at 3.13 and 2.96 cases per 100,000 women. However, Hail and Jazan had the lowest rates at 1.4 and 0.6 cases per 100,000 women, respectively. Compared to Jazan, the incidence rate ratio for the number of ovarian cancer cases was significantly higher (P<0.001 in the Makkah region at 6.4 (95% confidence interval [CI]: 4.13–9.83, followed by Riyadh at 6.3 (95% CI: 4.10–9.82, and the eastern region of Saudi Arabia at 4.52 (95% CI: 2.93–6.98. The predicted annual CIR and ASIR for ovarian cancer in Saudi Arabia could be defined by the equations 0.9 + (0.07× years and 1.71 + (0.09× years, respectively.Conclusion: We observed a slight increase in the CIRs and

  18. Factors associated with attrition, mortality, and loss to follow up after antiretroviral therapy initiation: data from an HIV cohort study in India

    Directory of Open Access Journals (Sweden)

    Gerardo Alvarez-Uria

    2013-09-01

    Full Text Available Background: Studies from sub-Saharan Africa have shown high incidence of attrition due to mortality or loss to follow-up (LTFU after initiating antiretroviral therapy (ART. India is the third largest country in the world in terms of HIV infected people, but predictors of attrition after ART initiation are not well known. Design: We describe factors associated with attrition, mortality, and LTFU in 3,159 HIV infected patients who initiated ART between 1 January 2007 and 4 November 2011 in an HIV cohort study in India. The study included 6,852 person-years with a mean follow-up of 2.17 years. Results: After 5 years of follow-up, the estimated cumulative incidence of attrition was 37.7%. There was no significant difference between attrition due to mortality and attrition due to LTFU. Having CD4 counts <100 cells/µl and being homeless [adjusted hazard ratio (aHR 3.1, 95% confidence interval (CI 2.6–3.8] were associated with a higher risk of attrition, and female gender (aHR 0.64, 95% CI 0.6–0.8 was associated with a reduced risk of attrition. Living near a town (aHR 0.82, 95% CI 0.7–0.999 was associated with a reduced risk of mortality. Being single (aHR 1.6, 95% CI 1.2–2.3, illiteracy (aHR 1.3, 95% CI 1.1–1.6, and age <25 years (aHR 1.3, 95% CI 1–1.8 were associated with an increased risk of LTFU. Although the cumulative incidence of attrition in patients diagnosed with tuberculosis after ART initiation was 47.4%, patients who started anti-tuberculous treatment before ART had similar attrition to patients without tuberculosis (36 vs. 35.2%, P=0.19 after four years of follow-up. Conclusions: In this cohort study, the attrition was similar to the one found in sub-Saharan Africa. Earlier initiation of ART, improving the diagnosis of tuberculosis before initiating ART, and giving more support to those patients at higher risk of attrition could potentially reduce the mortality and LTFU after ART initiation.

  19. A longitudinal observational study of brain atrophy rate reflecting four decades of multiple sclerosis: a comparison of serial 1D, 2D, and volumetric measurements from MRI images

    International Nuclear Information System (INIS)

    Martola, Juha; Zhang, Yi; Aspelin, Peter; Kristoffersen Wiberg, Maria; Bergstroem, Jakob; Fredrikson, Sten; Stawiarz, Leszek; Hillert, Jan; Flodmark, Olof; Lilja, Anders; Ekbom, Anders

    2010-01-01

    Multiple sclerosis (MS) has a variable progression with an early onset of atrophy. Individual longitudinal radiological evaluations (over decades) are difficult to perform due to the limited availability of magnetic resonance imaging (MRI) in the past, patients lost in follow-up, and the continuous updating of scanners. We studied a cohort with widespread disease duration at baseline. The observed individual atrophy rates over time of 10 years represented four decades of disease span. Thirty-seven MS patients (age range 24-65 years with disease duration 1-33 years) were consecutively selected and evaluated with MRI at baseline 1995 and in 1996. They were followed up for a decade (mean of 9.25 years, range 7.3-10 years) up to 2003-2005. Brain parenchymal volume and volumes of the supratentorial ventricles were analyzed with semi-automated volumetric measurements at three time points (1995, 1996, and 2003-2005). Volumetric differences were found over shorter periods of time (1-7 months); however, differences vanished by the end of follow-up. A uniform longitudinal decrease in brain volume and increase in ventricle volumes were found. Frontal horn width (1D) correlated strongest to 3D measures. No statistical differences of atrophy rates between MS courses were found. Supratentorial ventricular volumes were associated with disability and this association persisted during follow-up. Despite variable clinical courses, the degenerative effects of MS progression expressed in brain atrophy seem to uniformly progress over longer periods of time. These volumetric changes can be detected using 1D and 2D measurements performed on a routine PACS workstation. (orig.)

  20. Early observed transient prostate-specific antigen elevations on a pilot study of external beam radiation therapy and fractionated MRI guided High Dose Rate brachytherapy boost

    International Nuclear Information System (INIS)

    Singh, Anurag K; Godette, Denise J; Stall, Bronwyn R; Coleman, C Norman; Camphausen, Kevin; Ménard, Cynthia; Guion, Peter; Susil, Robert C; Citrin, Deborah E; Ning, Holly; Miller, Robert W; Ullman, Karen; Smith, Sharon; Crouse, Nancy Sears

    2006-01-01

    To report early observation of transient PSA elevations on this pilot study of external beam radiation therapy and magnetic resonance imaging (MRI) guided high dose rate (HDR) brachytherapy boost. Eleven patients with intermediate-risk and high-risk localized prostate cancer received MRI guided HDR brachytherapy (10.5 Gy each fraction) before and after a course of external beam radiotherapy (46 Gy). Two patients continued on hormones during follow-up and were censored for this analysis. Four patients discontinued hormone therapy after RT. Five patients did not receive hormones. PSA bounce is defined as a rise in PSA values with a subsequent fall below the nadir value or to below 20% of the maximum PSA level. Six previously published definitions of biochemical failure to distinguish true failure from were tested: definition 1, rise >0.2 ng/mL; definition 2, rise >0.4 ng/mL; definition 3, rise >35% of previous value; definition 4, ASTRO defined guidelines, definition 5 nadir + 2 ng/ml, and definition 6, nadir + 3 ng/ml. Median follow-up was 24 months (range 18–36 mo). During follow-up, the incidence of transient PSA elevation was: 55% for definition 1, 44% for definition 2, 55% for definition 3, 33% for definition 4, 11% for definition 5, and 11% for definition 6. We observed a substantial incidence of transient elevations in PSA following combined external beam radiation and HDR brachytherapy for prostate cancer. Such elevations seem to be self-limited and should not trigger initiation of salvage therapies. No definition of failure was completely predictive

  1. Star Formation Rates and Stellar Masses of z = 7-8 Galaxies from IRAC Observations of the WFC3/IR Early Release Science and the HUDF Fields

    Science.gov (United States)

    Labbé, I.; González, V.; Bouwens, R. J.; Illingworth, G. D.; Franx, M.; Trenti, M.; Oesch, P. A.; van Dokkum, P. G.; Stiavelli, M.; Carollo, C. M.; Kriek, M.; Magee, D.

    2010-06-01

    We investigate the Spitzer/IRAC properties of 36 z ~ 7 z 850-dropout galaxies and three z ~ 8 Y 098 galaxies derived from deep/wide-area WFC3/IR data of the Early Release Science, the ultradeep HUDF09, and wide-area NICMOS data. We fit stellar population synthesis models to the spectral energy distributions to derive mean redshifts, stellar masses, and ages. The z ~ 7 galaxies are best characterized by substantial ages (>100 Myr) and M/LV ≈ 0.2. The main trend with decreasing luminosity is that of bluing of the far-UV slope from β ~ -2.0 to β ~ -3.0. This can be explained by decreasing metallicity, except for the lowest luminosity galaxies (0.1L* z = 3), where low metallicity and smooth star formation histories (SFHs) fail to match the blue far-UV and moderately red H - [3.6] color. Such colors may require episodic SFHs with short periods of activity and quiescence ("on-off" cycles) and/or a contribution from emission lines. The stellar mass of our sample of z ~ 7 star-forming galaxies correlates with star formation rate (SFR) according to log M* = 8.70(±0.09) + 1.06(±0.10)log SFR, implying that star formation may have commenced at z > 10. No galaxies are found with SFRs much higher or lower than the past averaged SFR suggesting that the typical star formation timescales are probably a substantial fraction of the Hubble time. We report the first IRAC detection of Y 098-dropout galaxies at z ~ 8. The average rest-frame U - V ≈ 0.3 (AB) of the three galaxies are similar to faint z ~ 7 galaxies, implying similar M/L. The stellar mass density to M UV,AB Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with programs 11563, 9797. Based on observations with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under NASA contract 1407. Support for this work was provided by NASA through contract 125790 issued by JPL/Caltech. Based on service

  2. Success rate of IR midazolam sedation in combination with C-CLAD in pediatric dental patients—a prospective observational study

    Directory of Open Access Journals (Sweden)

    Malka Ashkenazi

    2014-03-01

    Full Text Available Objective. To evaluate the success rate of intra-rectal (IR midazolam in combination with nitrous oxide/oxygen (N2O sedation in young uncooperative dental patients when the local anesthesia is delivered by a computerized controlled local anesthetic delivery (C-CLAD.Study Design. This observational study consisted of 219 uncooperative children (age: 4.3 ± 1.69 y who received IR midazolam (0.4 mg/kg and N2O to complete their dental treatment. Measured variables included: child’s pain disruptive behavior during delivery of anesthesia by C-CLAD (CHEOP Scale, child behavior during treatment (Houpt scale, dental procedure performed, and side effects that appeared during treatment.Results. There was a high level of cooperation (mean score: 6.69 ± 2.1 during administration of local anesthesia. Good-to-excellent behavior was shown by 87% of the children during treatment. Planned treatment was completed by 184 (92% patients. No statistically significant changes were noticed in the oxygen saturation levels before and after treatment. Children with side effects included 3 (1.3% with nistagmus, 5 (2.3% with diplopia, and 18 (8.2% with hiccups. Three consecutive sedations decreased the overall behavior score by 5.7% compared to the first appointment (p < .05.Conclusions. IR midazolam-N2O sedation in combination with C-CLAD is very effective for delivery of dental treatment to young uncooperative children.

  3. The Impact of Junior Reserve Officer Training Corps and Other Youth Programs on Navy First-Term Attrition, Promotion, and Reenlistment

    National Research Council Canada - National Science Library

    Lamont, Roy A

    2007-01-01

    ...) and other youth programs significantly affects the performance of first-term Navy enlistees. This analysis makes use of multivariate models to estimate the causal effect of JROTC participation on first-term attrition, promotion and reenlistment...

  4. Engagement and Nonusage Attrition With a Free Physical Activity Promotion Program: The Case of 10,000 Steps Australia.

    Science.gov (United States)

    Guertler, Diana; Vandelanotte, Corneel; Kirwan, Morwenna; Duncan, Mitch J

    2015-07-15

    Data from controlled trials indicate that Web-based interventions generally suffer from low engagement and high attrition. This is important because the level of exposure to intervention content is linked to intervention effectiveness. However, data from real-life Web-based behavior change interventions are scarce, especially when looking at physical activity promotion. The aims of this study were to (1) examine the engagement with the freely available physical activity promotion program 10,000 Steps, (2) examine how the use of a smartphone app may be helpful in increasing engagement with the intervention and in decreasing nonusage attrition, and (3) identify sociodemographic- and engagement-related determinants of nonusage attrition. Users (N=16,948) were grouped based on which platform (website, app) they logged their physical activity: Web only, app only, or Web and app. Groups were compared on sociodemographics and engagement parameters (duration of usage, number of individual and workplace challenges started, and number of physical activity log days) using ANOVA and chi-square tests. For a subsample of users that had been members for at least 3 months (n=11,651), Kaplan-Meier survival curves were estimated to plot attrition over the first 3 months after registration. A Cox regression model was used to determine predictors of nonusage attrition. In the overall sample, user groups differed significantly in all sociodemographics and engagement parameters. Engagement with the program was highest for Web-and-app users. In the subsample, 50.00% (5826/11,651) of users stopped logging physical activity through the program after 30 days. Cox regression showed that user group predicted nonusage attrition: Web-and-app users (hazard ratio=0.86, 95% CI 0.81-0.93, Pworkplace challenges (hazard ratio=0.94, 95% CI 0.90-0.97, Pphysical activity logging days (hazard ratio=0.921, 95% CI 0.919-0.922, P<.001), and steps logged per day (hazard ratio=0.99999, 95% CI 0

  5. Determination of the best method to estimate glomerular filtration rate from serum creatinine in adult patients with sickle cell disease: a prospective observational cohort study

    Directory of Open Access Journals (Sweden)

    Arlet Jean-Benoît

    2012-08-01

    Full Text Available Abstract Background Sickle cell disease (SCD leads to tissue hypoxia resulting in chronic organ dysfunction including SCD associated nephropathy. The goal of our study was to determine the best equation to estimate glomerular filtration rate (GFR in SCD adult patients. Methods We conducted a prospective observational cohort study. Since 2007, all adult SCD patients in steady state, followed in two medical departments, have had their GFR measured using iohexol plasma clearance (gold standard. The Cockcroft-Gault, MDRD-v4, CKP-EPI and finally, MDRD and CKD-EPI equations without adjustment for ethnicity were tested to estimate GFR from serum creatinine. Estimated GFRs were compared to measured GFRs according to the graphical Bland and Altman method. Results Sixty-four SCD patients (16 men, median age 27.5 years [range 18.0-67.5], 41 with SS-genotype were studied. They were Sub-Saharan Africa and French West Indies natives and predominantly lean (median body mass index: 22 kg/m2 [16-33]. Hyperfiltration (defined as measured GFR >110 mL/min/1.73 m2 was detected in 53.1% of patients. Urinary albumin/creatinine ratio was higher in patients with hyperfiltration than in patients with normal GFR (4.05 mg/mmol [0.14-60] versus 0.4 mg/mmol [0.7-81], p = 0.01. The CKD-EPI equation without adjustment for ethnicity had both the lowest bias and the greatest precision. Differences between estimated GFRs using the CKP-EPI equation and measured GFRs decreased with increasing GFR values, whereas it increased with the Cockcroft-Gault and MDRD-v4 equations. Conclusions We confirm that SCD patients have a high rate of glomerular hyperfiltration, which is frequently associated with microalbuminuria or macroalbuminuria. In non-Afro-American SCD patients, the best method for estimating GFR from serum creatinine is the CKD-EPI equation without adjustment for ethnicity. This equation is particularly accurate to estimate high GFR values, including glomerular

  6. Attritional rupture of extensor pollicis longus: a rare complication following elastic stable intramedullary nailing of a paediatric radial fracture.

    LENUS (Irish Health Repository)

    Sproule, James A

    2011-01-01

    Elastic stable intramedullary nail fixation has become established as an acceptable method of treatment for diaphyseal fractures of both forearm bones in the paediatric population. It is considered safe, minimally invasive and does not compromise physeal growth. We report a case of delayed rupture of extensor pollicis longus due to attrition over the sharp edges of a protruding nail end after elastic stable intramedullary nailing of a paediatric radial diaphyseal fracture.

  7. On the radiative impact of aerosols on photolysis rates: comparison of simulations and observations in the Lampedusa island during the ChArMEx/ADRIMED campaign

    Directory of Open Access Journals (Sweden)

    S. Mailler

    2016-02-01

    Full Text Available The Mediterranean basin is characterized by large concentrations of aerosols from both natural and anthropogenic sources. These aerosols affect tropospheric photochemistry by modulating the photolytic rates. Three simulations of the atmospheric composition at basin scale have been performed with the CHIMERE chemistry-transport model for the period from 6 June to 15 July 2013 covered by the ADRIMED campaign, a campaign of intense measurements in the western Mediterranean basin. One simulation takes into account the radiative effect of the aerosols on photochemistry, the second one does not, and the third one is designed to quantify the model sensitivity to a bias in the ozone column. These simulations are compared to satellite and ground-based measurements, with a particular focus on the area of Lampedusa. Values of the aerosol optical depth (AOD are obtained from the MODIS instrument on the AQUA and TERRA satellites as well as from stations in the AERONET network and from the MFRSR sun photometer deployed at Lampedusa. Additional measurements from instruments deployed at Lampedusa either permanently or exceptionally are used for other variables: MFRSR sun photometer for AOD, diode array spectrometer for actinic fluxes, LIDAR for the aerosol backscatter, sequential sampler for speciation of aerosol and Brewer spectrophotometer for the total ozone column. It is shown that CHIMERE has a significant ability to reproduce observed peaks in the AOD, which in Lampedusa are mainly due to dust outbreaks during the ADRIMED period, and that taking into account the radiative effect of the aerosols in CHIMERE considerably improves the ability of the model to reproduce the observed day-to-day variations of the photolysis rate of ozone to O2 and O(1D, J(O1D, and that of NO2 to NO and O(3P, J(NO2. While in the case of J(O1D other variation factors such as the stratospheric ozone column are very important in representing correctly the day-to-day variations

  8. Prefrontal cortex activation is associated with a discrepancy between self- and observer-rated depression severities of major depressive disorder: a multichannel near-infrared spectroscopy study.

    Science.gov (United States)

    Akashi, Hiroyuki; Tsujii, Noa; Mikawa, Wakako; Adachi, Toru; Kirime, Eiji; Shirakawa, Osamu

    2015-03-15

    Studies on major depressive disorder (MDD) show that the degree of correlation between the Beck Depression Inventory (BDI) and Hamilton Depression Rating Scale (HAMD) varies widely. We aimed to determine whether this discrepancy reflects specific functional abnormalities in the frontotemporal cortex. Mildly depressed or euthymic patients with MDD (n=52), including 21 patients with MDD with the discrepancy, i.e., those with low HAMD17 scores (≤13) but high BDI-II scores (>28), and 31 patients without the discrepancy, i.e., those with low HAMD17 scores and low BDI-II scores (≤28), participated in the study along with 48 control subjects. Regional changes of oxygenated hemoglobin (oxy-Hb) levels during a verbal fluency task (VFT) were monitored using a 52-channel near-infrared spectroscopy (NIRS) device. In the frontotemporal regions, mean oxy-Hb changes induced by the VFT were significantly smaller in patients with MDD than in control subjects. In 5 channels within frontal regions, the increase in mean oxy-Hb levels was significantly greater in MDD patients with the BDI-HAMD discrepancy than in those without the discrepancy. In 6 channels within the frontal region of the patients with MDD, significant positive correlations were observed between mean oxy-Hb changes and BDI total scores (ρ=0.38-0.59; Pdepressed patients, particularly those with melancholia. The distinct pattern of activation of the prefrontal cortex suggests that MDD with the BDI-HAMD discrepancy is pathophysiologically different from MDD without the discrepancy. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Peroneus Brevis Attrition & Longitudinal Split Tear without Subluxation and Associated Hypertrophy of Peronal Tubercle" - Treatment of an Uncommon Lesion.

    Science.gov (United States)

    Tiwari, Mukesh; Singh, Varun; Bhargava, Rakesh

    2015-01-01

    Peroneus brevis tendinitis with its attritional longitudinal split rupture without any subluxation from peroneal groove and associated enlarged peroneal tubercle is un common presentation. A 40 year old female presented with moderate swelling and tenderness over the lateral and dorso-lateral aspect of left ankle with history of old trauma to ankle with swelling, persistant pain and difficulty in walking. On physical examination during passive eversion and inversion the excursion of the peroneal tendons was painful. Most tender point was just posterior to the tip of the fibula. During surgery we found the intact superior peroneal ligament with both peroneal tendons placed at normal site without subluxation, tendon sheath was inflamed and swollen, on further dissection we could see the attrition of inner surface of the peroneus brevis and a 2 cm longitudinal split tear of the same. Although rare but peroneus brevis tendon attrition and tear can occur without subluxation from peronal groove. Refractory ankle pain on lateral aspect presenting with on and off swelling should arise suspicion of peroneal tendon tear. Correct diagnosis and proper surgical repair can produce excellent results.

  10. Elements related to attrition of women faculty at the University of Pittsburgh, School of Medicine: A case study

    Science.gov (United States)

    Gandhi, Pooja

    Recent studies have shown that the number of women faculty in academic medicine is much lesser than the number of women that are graduating from medical schools. Many academic institutes face the challenge of retaining talented faculty and this attrition from academic medicine prevents career advancement of women faculty. This case study attempts to identify some of the reasons for dissatisfaction that may be related to the attrition of women medical faculty at the University of Pittsburgh, School of Medicine. Data was collected using a job satisfaction survey, which consisted of various constructs that are part of a faculty's job and proxy measures to gather the faculty's intent to leave their current position at the University of Pittsburgh or academic medicine in general. The survey results showed that although women faculty were satisfied with their job at the University of Pittsburgh, there are some important factors that influenced their decision of potentially dropping out. The main reasons cited by the women faculty were related to funding pressures, work-life balance, mentoring of junior faculty and the amount of time spent on clinical responsibilities. The analysis of proxy measures showed that if women faculty decided to leave University of Pittsburgh, it would most probably be due to better opportunity elsewhere followed by pressure to get funding. The results of this study aim to provide the School of Medicine at the University of Pittsburgh with information related to attrition of its women faculty and provide suggestions for implications for policy to retain their women faculty.

  11. Delineating the third age: joint models of older people's quality of life and attrition in Britain 2002-2010.

    Science.gov (United States)

    Tampubolon, Gindo

    2015-07-01

    In the public mind, later life is being transformed by the emerging possibility of a flourishing third age with sustained quality of life. We draw trajectories of life quality measured using CASP-19 over eight years. We refine these trajectories by jointly modelling attrition, since older people tend to leave longitudinal studies (attrite) not at random. Growth curve models are applied to the English Longitudinal Study of Ageing waves 1 to 5. Then joint model is estimated where attrition is considered. Extensive predictors are entered including demographic attributes, social and economic status, health conditions, and behaviours. Strong non-linear age trajectory of life quality is revealed by the growth curve models where the peak is achieved in the late 60s. Then the joint model uncovers the peak somewhat later in time, and also reveals secular improvement in life quality experienced by recent cohorts. Sharp estimates for many predictors of higher levels of life quality are also found. For the first time, the trajectories of life quality in the third age are drawn and improvement across cohorts is demonstrated. The contributions are estimated for predictors amenable to intervention such as social capital. This can help in policy discussion on improving the lives of older people in the third age.

  12. Attrition of limestones by impact loading in fluidized beds: The influence of reaction conditions

    Energy Technology Data Exchange (ETDEWEB)

    Scala, Fabrizio [Istituto di Ricerche sulla Combustione, Consiglio Nazionale delle Ricerche, Napoli (Italy); Salatino, Piero [Istituto di Ricerche sulla Combustione, Consiglio Nazionale delle Ricerche, Napoli (Italy); Dipartimento di Ingegneria Chimica, Universita degli Studi di Napoli Federico II, Napoli (Italy)

    2010-09-15

    The extent of attrition associated with impact loading was studied for five different limestones pre-processed in fluidized bed under different reaction conditions. The experimental procedure was based on the measurement of the amount and the particle size distribution of the debris generated upon impact of sorbent samples against a target at velocities between 10 and 45 m/s. The effect of calcination, sulfation and calcination/re-carbonation on impact damage was assessed. Fragmentation by impact loading of the limestones was significant and increased with the impact velocity. Lime samples displayed the largest propensity to undergo impact damage, followed by sulfated, re-carbonated and raw limestones. Fragmentation of the sulfated samples followed a pattern typical of the failure of brittle materials. On the other hand, the behaviour of lime samples better conformed to a disintegration failure mode, with extensive generation of very fine fragments. Raw limestone and re-carbonated lime samples followed either of the two patterns depending on the sorbent nature. The extent of particle fragmentation increased after multiple impacts, but the incremental amount of fragments generated upon one impact decreased with the number of successive impacts. (author)

  13. Prevention of weld-decay in austenitic stainless steel by using surface mechanical attrition treatment

    Science.gov (United States)

    Laleh, Majid; Kargar, Farzad; Rouhaghdam, Alireza Sabour

    2012-11-01

    Surface mechanical attrition treatment (SMAT) was applied to the samples of a type AISI 304 stainless steel in order to induce grain refinement as well as formation of twins. Transmission electron microscopy and X-ray diffraction analysis results showed that the average grain size at the surface of the SMATed sample was about 10 nm. The untreated and SMATed samples were then welded using a one-pass gas tungsten arc procedure. The heat-affected zone (HAZ) of the samples was examined by optical microscopy and corrosion tests. Results of the double loop electrochemical potentiokinetic reactivation tests showed that the degree of sensitization in the HAZ for the SMATed sample was very low as compared to that of the untreated one. The pre-SMATed sample was resistant to intergranular corrosion. This is mainly due to the formation of high density of twins which are not prone to carbide precipitation because of their regular and coherent atomic structure and extreme low grain boundary energy as compared with those of other grain boundaries.

  14. POSSIBILITY OF BENEFICIATION OF SILICA SAND FROM THE CROATIAN DEPOSITS USING ATTRITION SCRUBBING

    Directory of Open Access Journals (Sweden)

    Ivan Sobota

    2011-12-01

    Full Text Available To meet high quality requirements defined for specific industrial applications, the raw sand often has to be subjected to extensive physical and chemical processing. The possibility of achieving silica sand concentrate of required quality depends mostly on raw sand properties, primarily mineral impurity types and contents, and features of applied beneficiation methods. When the impurities occur in the form of oxide coatings on the surfaces of the single sand grains, attriton scrubbing is applied. By reducing the proportion of oxide coatings on the grains, the quality of sand can be improved. With the aim to determine the possibilities of the beneficiation of silica sand from significant Croatian deposits (“Vrtlinska”, “Štefanac” and “Španovica” and achieve concentrate grade complying with the requirements of domestic industry, laboratory tests were conducted on three raw sand samples with different SiO2 and impurity contents. Grain size distribution, chemical and mineral composition of raw sand samples, and the possibility of their quality improvement by applying the washing, classification and attrition scrubbing were defined by analysis of test results (the paper is published in Croatian.

  15. Retaining the mental health nursing workforce: early indicators of retention and attrition.

    Science.gov (United States)

    Robinson, Sarah; Murrells, Trevor; Smith, Elizabeth M

    2005-12-01

    In the UK, strategies to improve retention of the mental health workforce feature prominently in health policy. This paper reports on a longitudinal national study into the careers of mental health nurses in the UK. The findings reveal little attrition during the first 6 months after qualification. Investigation of career experiences showed that the main sources of job satisfaction were caregiving opportunities and supportive working relationships. The main sources of dissatisfaction were pay in relation to responsibility, paperwork, continuing education opportunities, and career guidance. Participants were asked whether they predicted being in nursing in the future. Gender and ethnicity were related to likelihood to remain in nursing in 5 years time. Age, having children, educational background, ethnic background, and time in first job were associated with likelihood of remaining in nursing at 10 years. Associations between elements of job satisfaction (quality of clinical supervision, ratio of qualified to unqualified staff, support from immediate line manager, and paperwork) and anticipated retention are complex and there are likely to be interaction effects because of the complexity of the issues. Sustaining positive experiences, remedying sources of dissatisfaction, and supporting diplomats from all backgrounds should be central to the development of retention strategies.

  16. Association between recruitment methods and attrition in Internet-based studies.

    Directory of Open Access Journals (Sweden)

    Paolo Bajardi

    Full Text Available Internet-based systems for epidemiological studies have advantages over traditional approaches as they can potentially recruit and monitor a wider range of individuals in a relatively inexpensive fashion. We studied the association between communication strategies used for recruitment (offline, online, face-to-face and follow-up participation in nine Internet-based cohorts: the Influenzanet network of platforms for influenza surveillance which includes seven cohorts in seven different European countries, the Italian birth cohort Ninfea and the New Zealand birth cohort ELF. Follow-up participation varied from 43% to 89% depending on the cohort. Although there were heterogeneities among studies, participants who became aware of the study through an online communication campaign compared with those through traditional offline media seemed to have a lower follow-up participation in 8 out of 9 cohorts. There were no clear differences in participation between participants enrolled face-to-face and those enrolled through other offline strategies. An Internet-based campaign for Internet-based epidemiological studies seems to be less effective than an offline one in enrolling volunteers who keep participating in follow-up questionnaires. This suggests that even for Internet-based epidemiological studies an offline enrollment campaign would be helpful in order to achieve a higher participation proportion and limit the cohort attrition.

  17. The Views of Ex-Police Officers on Child Abuse Case Attrition in the United Kingdom.

    Science.gov (United States)

    Krahenbuhl, Sarah J; Dent, Helen R

    2017-11-01

    Attrition in child abuse cases is of continuing concern. International research has produced evidence to suggest that the form and quality of the evidence available in many child abuse cases is of insufficient quality to allow progression through the judicial system. Recent revelations have led to an increase in public and professional awareness of the prevalence of child sexual abuse, and how this is managed by the legal and social care systems. The aim of this research was to explore the opinions of ex-Police Officers who had direct experience relating to the management of child abuse cases about the factors affecting case progression. Seven ex-Police Officers were interviewed and the transcribed data were thematically analyzed. The five main themes derived from the data were Global Myths, Assumptions, and Misconceptions; Suitability; Resources; Professionals' Attributes; and Working Together. These themes demonstrated that the primary issues indicated by ex-Police Officers were more about relationships between professionals, an understanding of the child's perspective, and their subsequent involvement in the legal processes than simply being related to a lack of resources.

  18. Observed Characteristics and Teacher Quality: Impacts of Sample Selection on a Value Added Model

    Science.gov (United States)

    Winters, Marcus A.; Dixon, Bruce L.; Greene, Jay P.

    2012-01-01

    We measure the impact of observed teacher characteristics on student math and reading proficiency using a rich dataset from Florida. We expand upon prior work by accounting directly for nonrandom attrition of teachers from the classroom in a sample selection framework. We find evidence that sample selection is present in the estimation of the…

  19. Tackle-related injury rates and nature of injuries in South African Youth Week tournament rugby union players (under-13 to under-18): an observational cohort study

    NARCIS (Netherlands)

    Burger, N.; Lambert, M.I.; Viljoen, W.; Brown, J.; Readhead, C.; Hendricks, S.

    2014-01-01

    Objectives: The tackle situation is most often associated with the high injury rates in rugby union. Tackle injury epidemiology in rugby union has previously been focused on senior cohorts but less is known about younger cohorts. The aim of this study was to report on the nature and rates of

  20. High Aneuploidy Rates Observed in Embryos Derived from Donated Oocytes are Related to Male Aging and High Percentages of Sperm DNA Fragmentation

    Directory of Open Access Journals (Sweden)

    Javier García-Ferreyra

    2015-01-01

    Full Text Available Capsule Male aging effects on aneuploidy rates in embryos. Objective Paternal age is associated with decreasing sperm quality; however, it is unknown if it influences chromosomal abnormalities in embryos. The objective of this study is to evaluate if the aneuploidy rates in embryos are affected by advanced paternal age. Methods A total of 286 embryos, obtained from 32 in vitro fertilization/intracytoplasmic sperm injection cycles with donated oocytes in conjunction with preimplantation genetic diagnosis, were allocated according to paternal age in three groups: Group A: ≤39 years (n = 44 embryos; Group B: 40-49 years (n = 154 embryos; and Group C: ≥50 years (n = 88 embryos. Fertilization rates, embryo quality at day 3, blastocyst development, and aneuploidy embryo rates were then compared. Results There was no difference in the seminal parameters (volume, concentration, and motility in the studied groups. Fertilization rate, percentages of zygotes underwent cleavage, and good quality embryos on day 3 were similar between the three evaluated groups. The group of men ≥50 years had significantly more sperm with damaged DNA, low blastocyst development rate, and higher aneuploidy rates in embryos compared to the other two evaluated groups ( P 50 years old.

  1. Actual exclusive breastfeeding rates and determinants among a cohort of children living in Gampaha district Sri Lanka: A prospective observational study

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    Perera Priyantha J

    2012-12-01

    Full Text Available Abstract Background Exclusive breastfeeding (EBF during the early months of life reduce infant morbidity and mortality. Current recommendation in Sri Lanka is to continue exclusive breastfeeding up to six months of age. Exclusive breastfeeding rates are generally assessed by the 24 recall method which overestimates the actual rates. The objective of this study was to determine actual exclusive breast feeding rates in a cohort of Sri Lankan children and to determine the reasons that lead to cessation of breastfeeding before six months of age. Methods From a cohort of 2215 babies born in Gampaha district, 500 were randomly selected and invited for the study. They were followed up at two (n = 404, four (n = 395 and six (n = 286 months. An interviewer administered questionnaire asked about feeding history and socio-demographic characteristics. Child health development record was used to assess the growth. Results Exclusive breastfeeding rates at two, four and six months were 98.0%, 75.4% and 71.3% respectively. The main reasons to stop exclusive breastfeeding between two to four months was concerns regarding weight gain and between four to six months were mothers starting to work. Majority of the babies that were not exclusively breastfed still continued to have breast milk. Mothers above 30 years had lower exclusive breastfeeding rates compared to younger mothers. Second born babies had higher rates than first borns. There was no significant association between maternal education and exclusive breastfeeding rates. Conclusions Exclusive breastfeeding rates were high among this cohort of children. A decrease in EBF was noted between two and four months. EBF up to six months does not cause growth failure. Mothers starting to work and concerns regarding adequacy of breast milk were the major reasons to cease EBF. The actual exclusive breastfeeding rates up to six months was 65.9%.

  2. Retrospective observation on contribution and limitations of screening for breast cancer with mammography in Korea: detection rate of breast cancer and incidence rate of interval cancer of the breast.

    Science.gov (United States)

    Lee, Kunsei; Kim, Hyeongsu; Lee, Jung Hyun; Jeong, Hyoseon; Shin, Soon Ae; Han, Taehwa; Seo, Young Lan; Yoo, Youngbum; Nam, Sang Eun; Park, Jong Heon; Park, Yoo Mi

    2016-11-18

    The purpose of this study was to determine the benefits and limitations of screening for breast cancer using mammography. Descriptive design with follow-up was used in the study. Data from breast cancer screening and health insurance claim data were used. The study population consisted of all participants in breast cancer screening from 2009 to 2014. Crude detection rate, positive predictive value and sensitivity and specificity of breast cancer screening and, incidence rate of interval cancer of the breast were calculated. The crude detection rate of breast cancer screening per 100,000 participants increased from 126.3 in 2009 to 182.1 in 2014. The positive predictive value of breast cancer screening per 100,000 positives increased from 741.2 in 2009 to 1,367.9 in 2014. The incidence rate of interval cancer of the breast per 100,000 negatives increased from 51.7 in 2009 to 76.3 in 2014. The sensitivities of screening for breast cancer were 74.6% in 2009 and 75.1% in 2014 and the specificities were 83.1% in 2009 and 85.7% in 2014. To increase the detection rate of breast cancer by breast cancer screening using mammography, the participation rate should be higher and an environment where accurate mammography and reading can be performed and reinforcement of quality control are required. To reduce the incidence rate of interval cancer of the breast, it will be necessary to educate women after their 20s to perform self-examination of the breast once a month regardless of participation in screening for breast cancer.

  3. Observing participating observation

    DEFF Research Database (Denmark)

    Keiding, Tina Bering

    2011-01-01

    Current methodology concerning participating observation in general leaves the act of observation unobserved. Approaching participating observation from systems theory offers fundamental new insights into the topic. Observation is always participation. There is no way to escape becoming...

  4. Observing participating observation

    DEFF Research Database (Denmark)

    Keiding, Tina Bering

    2010-01-01

    Current methodology concerning participating observation in general leaves the act of observation unobserved. Approaching participating observation from systems theory offers fundamental new insights into the topic. Observation is always participation. There is no way to escape becoming...

  5. Application of the Nelson model to four timelag fuel classes using Oklahoma field observations: Model evaluation and comparison with national Fire Danger Rating System algorithms

    Science.gov (United States)

    J. D. Carlson; Larry S. Bradshaw; Ralph M. Nelson; Randall R Bensch; Rafal Jabrzemski

    2007-01-01

    The application of a next-generation dead-fuel moisture model, the 'Nelson model', to four timelag fuel classes using an extensive 21-month dataset of dead-fuel moisture observations is described. Developed by Ralph Nelson in the 1990s, the Nelson model is a dead-fuel moisture model designed to take advantage of frequent automated weather observations....

  6. Not by strength alone : children's conflict expectations follow the logic of the asymmetric war of attrition.

    Science.gov (United States)

    Pietraszewski, David; Shaw, Alex

    2015-03-01

    The Asymmetric War of Attrition (AWA) model of animal conflict in evolutionary biology (Maynard Smith and Parker in Nature, 246, 15-18, 1976) suggests that an organism's decision to withdraw from a conflict is the result of adaptations designed to integrate the expected value of winning, discounted by the expected costs that would be incurred by continuing to compete, via sensitivity to proximate cues of how quickly each side can impose costs on the other (Resource Holding Potential), and how much each side will gain by winning. The current studies examine whether human conflict expectations follow the formalized logic of this model. Children aged 6-8 years were presented with third-party conflict vignettes and were then asked to predict the likely winner. Cues of ownership, hunger, size, strength, and alliance strength were systematically varied across conditions. Results demonstrate that children's expectations followed the logic of the AWA model, even in complex situations featuring multiple, competing cues, such that the actual relative costs and benefits that would accrue during such a conflict were reflected in children's expectations. Control conditions show that these modifications to conflict expectations could not have resulted from more general experimental artifacts or demand characteristics. To test the selectivity of these effects to conflict, expectations of search effort were also assessed. As predicted, they yielded a different pattern of results. These studies represent one of the first experimental tests of the AWA model in humans and suggest that future research on the psychology of ownership, conflict, and value may be aided by formalized models from evolutionary biology.

  7. Migration as a form of workforce attrition: a nine-country study of pharmacists.

    Science.gov (United States)

    Wuliji, Tana; Carter, Sarah; Bates, Ian

    2009-04-09

    There is a lack of evidence to inform policy development on the reasons why health professionals migrate. Few studies have sought to empirically determine factors influencing the intention to migrate and none have explored the relationship between factors. This paper reports on the first international attempt to investigate the migration intentions of pharmacy students and identify migration factors and their relationships. Responses were gathered from 791 final-year pharmacy students from nine countries: Australia, Bangladesh, Croatia, Egypt, Portugal, Nepal, Singapore, Slovenia and Zimbabwe. Data were analysed by means of Principal Components Analysis (PCA) and two-step cluster analysis to determine the relationships between factors influencing migration and the characteristics of subpopulations most likely and least likely to migrate. Results showed a significant difference in attitudes towards the professional and sociopolitical environment of the home country and perceptions of opportunities abroad between those who have no intention of migrating and those who intend to migrate on a long-term basis. Attitudes of students planning short-term migration were not significantly different from those of students who did not intend to migrate. These attitudes, together with gender, knowledge of other migrant pharmacists and past experiences abroad, are associated with an increased propensity for migration. Given the influence of the country context and environment on migration intentions, research and policy should frame the issue of migration in the context of the wider human resource agenda, thus viewing migration as one form of attrition and a symptom of other root causes. Remuneration is not an independent stand-alone factor influencing migration intentions and cannot be decoupled from professional development factors. Comprehensive human resource policy development that takes into account the issues of both remuneration and professional development are necessary

  8. An electromyographic study to assess the minimal time duration for using the splint to raise the vertical dimension in patients with generalized attrition of teeth

    Directory of Open Access Journals (Sweden)

    Aditi Nanda

    2011-01-01

    Full Text Available Background: To investigate the effect of restoration of lost vertical by centric stabilizing splint on electromyographic (EMG activity of masseter and anterior temporalis muscles bilaterally in patients with generalized attrition of teeth. Materials and Methods: EMG activity of anterior temporalis and masseter muscle was recorded bilaterally for 10 patients whose vertical was restored with centric stabilizing splint. The recording was done at postural rest position and in maximum voluntary clenching for each subject before the start of treatment, immediately after placement of splint and at subsequent recall visits, with splint and without the splint. Results: The EMG activity at postural rest position (PRP and maximum voluntary clench (MVC decreased till 1 month for both the muscles. In the third month, an increase in muscle activity toward normalization was noted at PRP, both with and without splint. At MVC in the third month, the muscle activity without splint decreased significantly as compared to pretreatment values for anterior temporalis and masseter, while with the splint an increase was seen beyond the pretreatment values. Conclusion: A definite response of anterior temporalis and masseter muscle was observed over a period of 3 months. This is suggestive that the reversible increase in vertical prior to irreversible intervention must be carried out for a minimum of 3 months to achieve neuromuscular deprogramming. This allows the muscle to get adapted to the new postural position and attain stability in occlusion following splint therapy.

  9. The role of nocturnal delivery and delivery during the holiday period in Finland on obstetric anal sphincter rupture rates- a population based observational study

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    Vehviläinen-Julkunen Katri

    2010-02-01

    Full Text Available Abstract Background Obstetric anal sphincter rupture (OASR is a serious complication of delivery, which frequently results in faecal incontinence despite primary repair and has serious implications for women's health. The objective of this study was to assess whether human factors, workload and staffing at night, at weekends and during holidays has an effect on the increasing OASR rates among all singleton vaginal deliveries (n = 514,741 having occurred between 1997 and 2007 in Finland. Women (n = 2,849 with OASR were compared in terms of possible risk factors to women without OASR using stepwise logistic regression analysis. Findings In Finland, the increase in OASR rate is striking, from 0.2% in 1997 to 0.9% in 2007. OASR rates varied from 0.49% to 0.58% (≤ 0.001 according to the time of day, and were lowest at night. After adjustment for patient-mix and the use of interventions, the risk of OASR was 11% lower (95% CI 3-18% at night and 15% lower (95% CI 3-26% in July - the main holiday month. Only 14% of the increased OASR risk during the day time (8-23.59 was attributable to vacuum assistance and birth weight, whereas the holiday period had no effect. Conclusions Decreased OASR rates at night and in July suggest that human factors such as decreased alertness due to fatigue or hospitals' administrative factors such as workload and staffing did not increase the rates of OASR.

  10. Incidence rate of non-Hodgkin’s lymphomas among males in Saudi Arabia: an observational descriptive epidemiological analysis of data from the Saudi Cancer Registry, 2001–2008

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    Alghamdi IG

    2014-06-01

    Full Text Available Ibrahim G Alghamdi,1,2 Issam I Hussain,1 Mohamed S Alghamdi,3 Ahlam A Dohal,4 Mansour M Alghamdi,4 Mohammed A El-Sheemy5 1School of Life Sciences, University of Lincoln, Lincoln, UK; 2Albaha University, Al Baha city, Saudi Arabia; 3General Directorate of Health Affairs, Ministry of Health, Al Baha, 4King Fahad Specialist Hospital, Dammam, Saudi Arabia; 5Research and Development, Lincoln Hospital, United Lincolnshire Hospitals NHSTrust, Lincoln, UK Background: This study describes epidemiological data of non-Hodgkin’s lymphoma (NHL diagnosed from 2001 to 2008 among Saudi men. Materials and methods: Retrospective data from all NHL cancer cases among Saudi men recorded in the Saudi Cancer Registry (SCR between January 2001 and December 2008 were used. Descriptive statistics, analysis of variance, Poisson regression, and simple linear regression were also used. Results: In total, 2,555 new cases of NHL were recorded between January 2001 and December 2008. The region of Riyadh, Saudi Arabia had the highest overall age-standardized incidence rate (ASIR at 7.8, followed by the Eastern region at 6.8, and Makkah at 6.1 per 100,000 men; however, Jazan, Hail, and Baha had the lowest average ASIRs at 2.5, 3.7, and 3.9 per 100,000 men, respectively. The incidence-rate ratio for the number of NHL cases was significantly higher in Riyadh (4.68, 95% confidence interval [CI] 4.11–5.32, followed by Makkah (4.47, 95% CI 3.94–5.07, and the Eastern region of Saudi Arabia (3.27, 95% CI 2.90–3.69 than that in the reference region of Jazan. Jouf had the highest changes in the ASIRs of NHL among Saudi men from 2001 and 2008 (5.0 per 100,000 men. Conclusion: A significant increase in the crude incidence rate and ASIR for NHL in Saudi Arabia between 2001 and 2008 was found. Riyadh, the Eastern region, and Makkah had the highest overall ASIR in Saudi Arabia. Jazan, Hail, and Baha had the lowest rates. Additionally, Riyadh, Makkah, and the Eastern region had the

  11. Optimizing removal of arsenic, chromium, copper, pentachlorophenol and polychlorodibenzo-dioxins/furans from the 1-4 mm fraction of polluted soil using an attrition process.

    Science.gov (United States)

    Guemiza, Karima; Coudert, Lucie; Tran, Lan Huong; Metahni, Sabrine; Blais, Jean-François; Besner, Simon; Mercier, Guy

    2017-08-01

    The objective of this study was to evaluate, at a pilot scale, the performance of an attrition process for removing As, Cr, Cu, pentachlorophenol (PCP) and polychlorodibenzodioxins and furans (PCDDF) from a 1-4 mm soil fraction. A Box-Behnken experimental design was utilized to evaluate the influence of several parameters (temperature, surfactant concentration and pulp density) and to optimize the main operating parameters of this attrition process. According to the results, the concentration of surfactant (cocamidopropylbetaine-BW) was the main parameter influencing both PCP and PCDDF removal from the 1-4 mm soil fraction by attrition. The behavior of each 2,3,7,8-PCDD/F congener during the attrition process was studied. The results indicated that the concentration of surfactant had a significant and positive effect on the removal of almost all of the dioxin and furan. The removal of 56%, 55%, 50%, 67% and 62% of the contaminants were obtained for As, Cr, Cu, PCP and PCDDF, respectively, using the optimized conditions ([BW]= 2% (w.w-1), T = 25°C and PD = 40% (w.w-1)). These results showed that attrition in the presence of a surfactant can be efficiently used to