On the Modeling of Electrical Effects Experienced by Space Explorers During Extra Vehicular Activities: Intracorporal Currents, Resistances, and Electric Fields

NASA Technical Reports Server (NTRS)

Cela, Carlos J.; Loizos, Kyle; Lazzi, Gianluca; Hamilton, Douglas; Lee, Raphael C.

2011-01-01

Recent research has shown that space explorers engaged in Extra Vehicular Activities (EVAs) may be exposed, under certain conditions, to undesired electrical currents. This work focuses on determining whether these undesired induced electrical currents could be responsible for involuntary neuromuscular activity in the subjects, possibly caused by either large diameter peripheral nerve activation or reflex activity from cutaneous afferent stimulation. An efficient multiresolution variant of the admittance method along with a millimeter-resolution model of a male human body were used to calculate induced electric fields, resistance between contact electrodes used to simulate the potential exposure condition, and currents induced in the human body model. Results show that, under realistic exposure conditions using a 15V source, current density magnitudes and total current injected are well above previously reported startle reaction thresholds. This indicates that, under the considered conditions, the subjects could experience involuntary motor response.

Current role challenges in New Zealand aged residential care: the potential consequences for healthcare assistant role expansion.

PubMed

Shannon, Kay; McKenzie-Green, Barbara

2016-01-01

Challenges facing healthcare assistants in aged residential care are a focus of global debate. These challenges involve remuneration, education, skill mix, work conditions and organisational structures. We enter the discussion by acknowledging current work, education and remuneration for healthcare assistants. We then consider the supervisory relationships between registered nurses (RNs), enrolled nurses (ENs) and healthcare assistants, educational levels for RNs, ENs and healthcare assistants, and the interplay between organisation and practice in aged residential care. We suggest that improving work for the healthcare assistant has the potential to lead change in all role levels. Discussion paper. We argue that adjustments to work structures, education and skill advancement of RNs, ENs and healthcare assistants could improve staff working conditions and clarify practice boundaries. The ultimate result is likely to be an improvement to quality of care and the life of residents in aged residential care.

Health Status and Working Condition of Migrant Workers: Major Public Health Problems

PubMed Central

Bener, Abdulbari

2017-01-01

Background: Very little research and survey have been performed on the occupational health, hazards, and working condition of urban and rural of workers in Qatar. The aim of the current study is to identify the health status, lifestyle condition, working-related problems, and accidents experienced by Indian subcontinental migrants (ISCM) in Qatar and their access to health-care facilities. Methods: This is a cross-sectional study based on a representative sample of 1186 workers and study covering sociodemographic characteristics, medical conditions, and health-seeking behaviors and personal experience. Results: There were statistically significant differences between semi-urban and urban migrant workers in terms of educational, occupation, income, working hours, and accommodation type (P < 0.001). Furthermore, there were statistically significant differences between migrant workers in terms of body mass index, delay in receiving salary, the right to medical insurance and sick day entitlement, cigarettes and shisha smoking, amenities, having on-site safety measure, and sleeping hours (P < 0.01). Moreover, there were statistically significant differences between semi-urban and urban migrant workers in terms of pain, cardiopulmonary, gastrointestinal, and pseudoneurologic and medical symptoms (P < 0.01). Multiple logistic regression was used for predictors’ health problems in migrant workers such as the absence of drinking water, tap water availability, safety facility tools, occupational status, shisha smoking, toilet facility, working hours, and accommodation type were considered the strong predictors. Conclusions: The current study revealed that there is a lack of insufficient information for the migrants about their lifestyle, medical conditions, health risks, injury, and rights privilege in relation to legal working condition and health services. PMID:28966757

Health Status and Working Condition of Migrant Workers: Major Public Health Problems.

PubMed

Bener, Abdulbari

2017-01-01

Very little research and survey have been performed on the occupational health, hazards, and working condition of urban and rural of workers in Qatar. The aim of the current study is to identify the health status, lifestyle condition, working-related problems, and accidents experienced by Indian subcontinental migrants (ISCM) in Qatar and their access to health-care facilities. This is a cross-sectional study based on a representative sample of 1186 workers and study covering sociodemographic characteristics, medical conditions, and health-seeking behaviors and personal experience. There were statistically significant differences between semi-urban and urban migrant workers in terms of educational, occupation, income, working hours, and accommodation type ( P < 0.001). Furthermore, there were statistically significant differences between migrant workers in terms of body mass index, delay in receiving salary, the right to medical insurance and sick day entitlement, cigarettes and shisha smoking, amenities, having on-site safety measure, and sleeping hours ( P < 0.01). Moreover, there were statistically significant differences between semi-urban and urban migrant workers in terms of pain, cardiopulmonary, gastrointestinal, and pseudoneurologic and medical symptoms ( P < 0.01). Multiple logistic regression was used for predictors' health problems in migrant workers such as the absence of drinking water, tap water availability, safety facility tools, occupational status, shisha smoking, toilet facility, working hours, and accommodation type were considered the strong predictors. The current study revealed that there is a lack of insufficient information for the migrants about their lifestyle, medical conditions, health risks, injury, and rights privilege in relation to legal working condition and health services.

Working and caring for a child with chronic illness: A review of current literature.

PubMed

Kish, A M; Newcombe, P A; Haslam, D M

2018-05-01

Advances in medical knowledge have contributed to the increase in the number of children living with some form of long-term chronic illness or condition. As a consequence of these advancements, treatments that are more accessible and easier to administer, usually within a child's home, have been developed. However, this may mean that parents take on greater treatment responsibility and require extra time and energy to meet these tasks, additional to other responsibilities. This review paper aims to summarize and critique existing literature on working parents of children with a chronic condition, by focusing on patterns of parent work, the challenges experienced, and the flow-on consequences to well-being. Employing a narrative, meta-synthesis of the current literature, this review identified 3 key themes related to working parents of children with chronic illness. The paper first identifies that although employment is less common, these parents are not necessarily nonworking. Second, these parents experience numerous challenges including balancing work and family, time constraints, stress, and feelings of "doing it all." And third, the above challenges lead to additional impacts on parental quality of life. This review summarizes what is currently known about work patterns, challenges, and consequences in parents of children with chronic conditions. Employment is clearly impacted for these parents. Although workplace challenges have been extensively researched, other challenges (eg, personal and family) and impacts on their well-being have not. This review discusses the present standing of this research. It outlines the strengths and limitations of the current literature, makes recommendations for future research, and suggests theoretical and practical implications of the further findings. © 2018 John Wiley & Sons Ltd.

Anomalous current in diffusive ferromagnetic Josephson junctions

NASA Astrophysics Data System (ADS)

Silaev, M. A.; Tokatly, I. V.; Bergeret, F. S.

2017-05-01

We demonstrate that in diffusive superconductor/ferromagnet/superconductor (S/F/S) junctions a finite, anomalous Josephson current can flow even at zero phase difference between the S electrodes. The conditions for the observation of this effect are noncoplanar magnetization distribution and a broken magnetization inversion symmetry of the superconducting current. The latter symmetry is intrinsic for the widely used quasiclassical approximation and prevented previous works based on this approximation from obtaining the Josephson anomalous current. We show that this symmetry can be removed by introducing spin-dependent boundary conditions for the quasiclassical equations at the superconducting/ferromagnet interfaces in diffusive systems. Using this recipe, we consider generic multilayer magnetic systems and determine the ideal experimental conditions in order to maximize the anomalous current.

Permanent Income and the Black-White Test Score Gap. NBER Working Paper No. 17610

ERIC Educational Resources Information Center

Rothstein, Jesse; Wozny, Nathan

2011-01-01

Analysts often examine the black-white test score gap conditional on family income. Typically only a current income measure is available. We argue that the gap conditional on permanent income is of greater interest, and we describe a method for identifying this gap using an auxiliary data set to estimate the relationship between current and…

Transcranial direct current stimulation to enhance cognition in euthymic bipolar disorder.

PubMed

Martin, Donel M; Chan, Herng-Nieng; Alonzo, Angelo; Green, Melissa J; Mitchell, Philip B; Loo, Colleen K

2015-12-01

To investigate the use of transcranial direct current stimulation (tDCS) for enhancing working memory and sustained attention in euthymic patients with bipolar disorder. Fifteen patients with bipolar disorder received anodal left prefrontal tDCS with an extracephalic cathode (prefrontal condition), anodal left prefrontal and cathodal cerebellar tDCS (fronto-cerebellar condition), and sham tDCS given 'online' during performance on a working memory and sustained attention task in an intra-individual, cross-over, sham-controlled experimental design. Exploratory cluster analyses examined responders and non-responders for the different active tDCS conditions on both tasks. For working memory, approximately one-third of patients in both active tDCS conditions showed performance improvement. For sustained attention, three of 15 patients showed performance improvement with prefrontal tDCS. Responders to active tDCS for working memory performed more poorly on the task during sham tDCS compared to non-responders. A single session of active prefrontal or fronto-cerebellar tDCS failed to improve working memory or sustained attention performance in euthymic patients with bipolar disorder. Several important considerations are discussed in relation to future studies investigating tDCS for enhancing cognition in patients with bipolar disorder. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Factors associated with pharmacists' perceptions of their working conditions and safety and effectiveness of patient care.

PubMed

Tsao, Nicole W; Lynd, Larry D; Gastonguay, Louise; Li, Kathy; Nakagawa, Bob; Marra, Carlo A

2016-01-01

In recent years, the role of pharmacists has changed, as have various provincial legislations, which now allow pharmacists to provide additional health services to patients. With these changes comes growing concern about how well the current pharmacy working environment is adapting and whether it may also be creating work-related stress that may contribute to potentially unsafe practices of patient care. To characterize the current working conditions of pharmacists in British Columbia, an online survey was developed and distributed to all College of Pharmacists of BC (CPBC) registrants by email. The survey consisted of questions on pharmacists' demographics, practice setting and perceptions of workplace conditions. Responses were collected from October 1 to November 10, 2013. All data were summarized using descriptive statistics, and regression models were constructed to assess the association between various factors and pharmacists' self-reported working conditions. Twenty-three percent (1241/5300) of pharmacists registered with the CPBC responded, with 78% working in the community pharmacy setting (58% chain, 19% independent). Pharmacists mostly disagreed with the statements that they had enough time for breaks or lunches or to do their jobs, as well as enough staffing support. Pharmacists' perceptions of their workplace environment were negatively associated with workplace-imposed advanced service quotas (for medication reviews, immunizations and prescription adaptations); being employed at chain store pharmacies, compared to independent pharmacies or hospitals/long-term care settings; and higher prescription volume. Pharmacists working in chain community pharmacies who are required to meet monthly quotas for expanded services reported a substantial negative impact on their working conditions and perceived safety of patient care. Can Pharm J (Ott) 2016;149:xx-xx.

Health inequalities among workers with a foreign background in Sweden: do working conditions matter?

PubMed

Dunlavy, Andrea C; Rostila, Mikael

2013-07-10

Employment and working conditions are key social determinants of health, yet current information is lacking regarding relationships between foreign background status, working conditions and health among workers in Sweden. This study utilized cross-sectional data from the 2010 Swedish Level of Living Survey (LNU) and the Level of Living Survey for Foreign Born Persons and their Children (LNU-UFB) to assess whether or not health inequalities exist between native Swedish and foreign background workers and if exposure to adverse psychosocial and physical working conditions contributes to the risk for poor health among foreign background workers. A sub-sample of 4,021 employed individuals aged 18-65 was analyzed using logistic regression. Eastern European, Latin American and Other Non-Western workers had an increased risk of both poor self-rated health and mental distress compared to native Swedish workers. Exposure to adverse working conditions only minimally influenced the risk of poor health. Further research should examine workers who are less integrated or who have less secure labor market attachments and also investigate how additional working conditions may influence associations between health and foreign background status.

Homeworking: Home Office or Home Sweatshop? Report on Current Conditions of Homeworkers in Toronto's Garment Industry. NALL Working Paper.

ERIC Educational Resources Information Center

Ng, Roxana; Wong, Renita Yuk-Lin; Choi, Angela

The current conditions of home workers in the garment industry in Toronto, Canada, were examined through in-depth telephone interviews with 30 Chinese-speaking immigrant women who were employed as home workers in 1999. The paper dicusses the formal training and informal learning experiences of immigrant woman who are garment workers. A comparison…

[The social hygiene problems in the operator work of hydroelectric power station workers and the means for enhancing work capacity].

PubMed

Karakashian, A N; Lepeshkina, T R; Ratushnaia, A N; Glushchenko, S S; Zakharenko, M I; Lastovchenko, V B; Diordichuk, T I

1993-01-01

Weight, tension and harmfulness of professional activity, peculiarities of labour conditions and characteristics of work, shift dynamics of operative personnel's working capacity were studied in the course of 8-hour working day currently accepted at hydroelectric power stations (HEPS) and experimental 12-hour schedule. Working conditions classified as "admissible", positive dynamics of operators' state, their social and material contentment were a basis for 12-hour two-shift schedule to be recommended as more appropriate. At the same time, problem of optimal shift schedules for operative personnel of HEPS remains unsolved and needs to be further explored.

The effects of extended work under sleep deprivation conditions on team-based performance.

PubMed

Pilcher, June J; Vander Wood, Melissa A; O'Connell, Kristina L

2011-07-01

Teamwork is becoming increasingly common in today's workplaces; however, little research has examined how well teams perform under sleep deprivation conditions. The purpose of the current study was to examine the effect of extended work under sleep deprivation conditions on team performance. A total of 24 participants were sleep deprived for 30 h and completed 16 h of sustained operations during the last portion of the sleep deprivation period. The participants completed the Wombat, a complex task including vigilance and cognitive components, with a partner in four 24-min testing sessions during the sustained operations period. The results indicated that team performance increased during the work period while, within each testing session, team performance on vigilance tasks remained stable and overall performance decreased. The current results suggest that performance on two-person teams results in improved performance but does not fully counteract the decreases in performance within each work period. Performance in two-person teams increased across an extended work shift under sleep deprivation conditions. However, vigilance performance remained stable while overall performance decreased when examining performance in 8-min segments. These results suggest that averaging team-based performance over a longer testing period may mask the negative effects of sleep deprivation. STATEMENT OF RELEVANCE: Performance in two-person teams increased across an extended work shift under sleep deprivation conditions. However, vigilance performance remained stable while overall performance decreased when examining performance in 8-min segments. These results suggest that averaging team-based performance over a longer testing period may mask the negative effects of sleep deprivation.

Working-Class Jobs and New Parents' Mental Health

ERIC Educational Resources Information Center

Perry-Jenkins, Maureen; Smith, JuliAnna Z.; Goldberg, Abbie E.; Logan, Jade

2011-01-01

Little research has explored linkages between work conditions and mental health in working-class employed parents. The current study aims to address this gap, employing hierarchical linear modeling techniques to examine how levels of and changes in job autonomy, job urgency, supervisor support, and coworker support predicted parents' depressive…

Preparing Social Work Students for Integrated Health Care: Results from a National Study

ERIC Educational Resources Information Center

Held, Mary Lehman; Mallory, Kim Crane; Cummings, Sherry

2017-01-01

Integrated health care serves a vital role in addressing interrelated physical and behavioral health conditions, but social work graduates often lack sufficient training to work on integrated teams. We surveyed 94 deans of master's of social work programs to assess the current and planned integrated health care curricula and the aptitude of…

Work disability resulting from chronic health conditions.

PubMed

Lerner, Debra; Allaire, Saralynn H; Reisine, Susan T

2005-03-01

To describe current programs and policies for addressing work disability among adults with chronic health conditions, and to identify opportunities for new research aimed at reducing the problem. The authors conducted secondary data analysis and a literature review. Millions of Americans with a chronic health condition have a work disability or are at risk of developing one. This public health problem is costing hundreds of billions of dollars a year nationally in lost productivity and diminishing the quality of life of millions of Americans. The medical care system, employers, and government--three traditional sources of help for adults with chronic health problems--are not sufficiently oriented toward the primary or secondary prevention of work disability. New research is urgently needed to reduce the burden of work disability on individuals and society.

Intervention strategies to eliminate truck-related fatalities in surface coal mining in West Virginia.

PubMed

Zhang, Meng; Kecojevic, Vladislav

2016-01-01

The main objective of this review was to build upon a previous study on the root causes of truck-related fatalities in surface coal mining operations in West Virginia, and to develop intervention strategies to eliminate these fatalities. This review considers a two-pronged approach to accident prevention: one that is fundamental and traditional (safety regulations, training and education, and engineering of the work environment); and one that is innovative and creative (e.g., applying technological advances to better control and eliminate the root causes of accidents). Suggestions for improving current training and education system are proposed, and recommendations are provided on improving the safety of mine working conditions, specifically safety conditions on haul roads, dump sites, and loading areas. We also discuss various currently available technologies that can help prevent haul truck-related fatal accidents. The results of this review should be used by mine personnel to help create safer working conditions and decrease truck-related fatalities in surface coal mining.

Prevalence of and interest in unionization among staff pharmacists.

PubMed

Zgarrick, David P; McHugh, Patrick P; Droege, Marcus

2006-09-01

Although the propensity for staff pharmacists to join a labor union has never been high, conditions in the profession and workplace have changed over the last decade. Some of these changes may result in staff pharmacists joining a labor union, as well as increased interest in staff pharmacists who are currently not union members to join. The objectives of this study were to (1) assess the degree of union membership among staff pharmacists in 6 states, (2) compare the practice settings, work activities and conditions, compensation, and demographic characteristics between union and nonunion staff pharmacists, (3) assess the level of interest in joining a union among nonunion staff pharmacists, and (4) compare the practice settings, work activities and working conditions, wages and benefits, and demographic characteristics between nonunion staff pharmacists interested in joining a union and nonunion staff pharmacists who were not interested in joining a union. A biennial pharmacist compensation study was conducted in 6 states (Florida, Iowa, Illinois, Minnesota, Tennessee, Wisconsin) in late 2003. Randomly selected pharmacists were mailed a self-administered questionnaire asking about their practice setting, work activities and conditions, wages and benefits, and demographic characteristics. Respondents were also asked to indicate current membership in a union and, if not a member, their desire to unionize their workplace. Compensation and unionization data were provided by 2,180 respondents (27% usable response rate), of which 1,226 (56%) were staff pharmacists. Eight percent of the staff pharmacists were union members, whereas 18% of nonunion members would vote to unionize their workplace. There were few statistically significant differences between union and nonunion staff pharmacists regarding work activities, working conditions, and hourly wages. However, the benefits provided to union staff pharmacists differed from those provided to nonunion staff pharmacists in several ways. Union staff pharmacists were younger than their nonunion counterparts (40.9 vs 44.5 years, P=.01), yet had worked for their current employers a longer time (11.1 vs 7.3 years, P=.03). Nonunion staff pharmacists interested in joining a union differed from those who would not by practice location and setting, working conditions, and benefits. Although the union membership rate among staff pharmacists is relatively low, there are geographic and practice areas where membership rates are higher. Differences in work activities, working conditions, wages, and benefits were noted between union and nonunion staff pharmacists as well as between those who would join a union and those who would not. These differences merit further investigation, especially with respect to evaluating the effectiveness of unions and identifying factors that may lead nonunionized staff pharmacists to join a union.

Swept-Ramp Detonation Initiation Performance in a High-Pressure Pulse Detonation Combustor

DTIC Science & Technology

2010-12-01

conditions at sea level, but at elevated temperatures of 300–500°F in the combustor. The current work was motivated by a need to experimentally...The current work was motivated by a need to experimentally evaluate the detonation initiation performance of a PDC at elevated combustor pressures...High-Speed Propulsion Technologies (After [3]) .....................2 Figure 2. Stationary One-Dimensional Combustion Wave Model (From [7

National working conditions surveys in Latin America: comparison of methodological characteristics

PubMed Central

Merino-Salazar, Pamela; Artazcoz, Lucía; Campos-Serna, Javier; Gimeno, David; Benavides, Fernando G.

2015-01-01

Background: High-quality and comparable data to monitor working conditions and health in Latin America are not currently available. In 2007, multiple Latin American countries started implementing national working conditions surveys. However, little is known about their methodological characteristics. Objective: To identify commonalities and differences in the methodologies of working conditions surveys (WCSs) conducted in Latin America through 2013. Methods: The study critically examined WCSs in Latin America between 2007 and 2013. Sampling design, data collection, and questionnaire content were compared. Results: Two types of surveys were identified: (1) surveys covering the entire working population and administered at the respondent's home and (2) surveys administered at the workplace. There was considerable overlap in the topics covered by the dimensions of employment and working conditions measured, but less overlap in terms of health outcomes, prevention resources, and activities. Conclusions: Although WCSs from Latin America are similar, there was heterogeneity across surveyed populations and location of the interview. Reducing differences in surveys between countries will increase comparability and allow for a more comprehensive understanding of occupational health in the region. PMID:26079314

National working conditions surveys in Latin America: comparison of methodological characteristics.

PubMed

Merino-Salazar, Pamela; Artazcoz, Lucía; Campos-Serna, Javier; Gimeno, David; Benavides, Fernando G

2015-01-01

High-quality and comparable data to monitor working conditions and health in Latin America are not currently available. In 2007, multiple Latin American countries started implementing national working conditions surveys. However, little is known about their methodological characteristics. To identify commonalities and differences in the methodologies of working conditions surveys (WCSs) conducted in Latin America through 2013. The study critically examined WCSs in Latin America between 2007 and 2013. Sampling design, data collection, and questionnaire content were compared. Two types of surveys were identified: (1) surveys covering the entire working population and administered at the respondent's home and (2) surveys administered at the workplace. There was considerable overlap in the topics covered by the dimensions of employment and working conditions measured, but less overlap in terms of health outcomes, prevention resources, and activities. Although WCSs from Latin America are similar, there was heterogeneity across surveyed populations and location of the interview. Reducing differences in surveys between countries will increase comparability and allow for a more comprehensive understanding of occupational health in the region.

Health Inequalities among Workers with a Foreign Background in Sweden: Do Working Conditions Matter?

PubMed Central

Dunlavy, Andrea C.; Rostila, Mikael

2013-01-01

Employment and working conditions are key social determinants of health, yet current information is lacking regarding relationships between foreign background status, working conditions and health among workers in Sweden. This study utilized cross-sectional data from the 2010 Swedish Level of Living Survey (LNU) and the Level of Living Survey for Foreign Born Persons and their Children (LNU-UFB) to assess whether or not health inequalities exist between native Swedish and foreign background workers and if exposure to adverse psychosocial and physical working conditions contributes to the risk for poor health among foreign background workers. A sub-sample of 4,021 employed individuals aged 18–65 was analyzed using logistic regression. Eastern European, Latin American and Other Non-Western workers had an increased risk of both poor self-rated health and mental distress compared to native Swedish workers. Exposure to adverse working conditions only minimally influenced the risk of poor health. Further research should examine workers who are less integrated or who have less secure labor market attachments and also investigate how additional working conditions may influence associations between health and foreign background status. PMID:23846669

Borderline personality symptoms and work performance: a population-based survey.

PubMed

Juurlink, Trees T; Ten Have, Margreet; Lamers, Femke; van Marle, Hein J F; Anema, Johannes R; de Graaf, Ron; Beekman, Aartjan T F

2018-06-19

This study aims to elucidate the interplay between borderline personality symptoms and working conditions as a pathway for impaired work performance among workers in the general population. Cross-sectional data from the Netherlands Mental Health Survey and Incidence Study-2 (NEMESIS-2) were used, including 3672 workers. Borderline personality symptoms were measured with the International Personality Disorder Examination (IPDE) questionnaire. Working conditions (decision latitude, psychological job demands, job security and co-worker support) were assessed with the Job Content Questionnaire (JCQ). Impaired work performance was assessed as total work loss days per month, defined as the sum of days of three types of impaired work performance (inability to work, cut-down to work, and diminished quality at work). These were assessed with the WHO Disability Assessment Schedule (WHO-DAS). Common mental disorders (CMD) were assessed with the Composite International Diagnostic Interview (CIDI). Number of borderline personality symptoms was consistently associated with impaired work performance, even after controlling for type or number of adverse working conditions and co-occurrence of CMD. Borderline personality symptoms were associated with low decision latitude, job insecurity and low co-worker support. The relationship between borderline personality symptoms and work performance diminished slightly after controlling for type or number of working conditions. The current study shows that having borderline personality symptoms is a unique determinant of work performance. This association seems partially explained through the impact of borderline personality symptoms on working conditions. Future studies are warranted to study causality and should aim at diminishing borderline personality symptoms and coping with working conditions.

Successful Aging in the Context of the Disablement Process: Working and Volunteering as Moderators on the Association Between Chronic Conditions and Subsequent Functional Limitations.

PubMed

Kail, Ben Lennox; Carr, Dawn C

2017-03-01

This study evaluated the successful aging model by assessing the impact of two forms of productive engagement-working and volunteering-as potential interventions in the process of disablement. The Health and Retirement Study was used to (a) estimate two-stage selection equations of (i) currently working part time and full time and (ii) currently volunteering less than 100 hours and volunteering 100 hours or more per year (net of chronic health problems) and (b) assess whether, net of selection, working, and volunteering moderate the association between chronic conditions and subsequent functional limitations. Chronic conditions were associated with elevated levels of subsequent functional limitations, whereas both working and volunteering were associated with lower levels of subsequent functional limitations. Moreover, workers and volunteers of less than 100 hours per year experienced a reduction in the association of chronic conditions on subsequent functional limitations. This research highlights the role of productive engagement as a key element in successful aging. Not only do work and volunteering have direct associations with health outcomes themselves, but they also act as potential interventions in the process of disablement by attenuating the way in which chronic conditions are translated into subsequent functional limitations. This suggests that (a) future research should apply successful aging models to health processes as well as health outcomes and (b) policy makers should support social institutions that foster late-life productive engagement. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Fatigue Crack Growth Behavior Evaluation of Grainex Mar-M 247 for NASA's High Temperature, High Speed Turbine Seal Test Rig

NASA Technical Reports Server (NTRS)

Delgado, Irebert R.; Steinetz, Bruce M.; Rimnac, Clare M.; Lewandowski, John J.

2008-01-01

The fatigue crack growth behavior of Grainex Mar-M 247 is evaluated for NASA s Turbine Seal Test Facility. The facility is used to test air-to-air seals primarily for use in advanced jet engine applications. Because of extreme seal test conditions of temperature, pressure, and surface speeds, surface cracks may develop over time in the disk bolt holes. An inspection interval is developed to preclude catastrophic disk failure by using experimental fatigue crack growth data. By combining current fatigue crack growth results with previous fatigue strain-life experimental work, an inspection interval is determined for the test disk. The fatigue crack growth life of the NASA disk bolt holes is found to be 367 cycles at a crack depth of 0.501 mm using a factor of 2 on life at maximum operating conditions. Combining this result with previous fatigue strain-life experimental work gives a total fatigue life of 1032 cycles at a crack depth of 0.501 mm. Eddy-current inspections are suggested starting at 665 cycles since eddy current detection thresholds are currently at 0.381 mm. Inspection intervals are recommended every 50 cycles when operated at maximum operating conditions.

A Galvanic Sensor for Monitoring the Corrosion Condition of the Concrete Reinforcing Steel: Relationship Between the Galvanic and the Corrosion Currents

PubMed Central

Pereira, Elsa Vaz; Figueira, Rita Bacelar; Salta, Maria Manuela Lemos; da Fonseca, Inês Teodora Elias

2009-01-01

This work reports a study carried out on the design and performance of galvanic and polarization resistance sensors to be embedded in concrete systems for permanent monitoring of the corrosion condition of reinforcing steel, aiming to establish a correlation between the galvanic currents, Igal, and the corrosion currents, Icorr, estimated from the polarization resistance, Rp. Sensors have been tested in saturated Ca(OH)2 aqueous solutions, under a variety of conditions, simulating the most important parameters that can accelerate the corrosion of concrete reinforcing steel, such as carbonation, ingress of chloride ions, presence or absence of O2. For all the conditions, the influence of temperature (20 to 55 °C) has also been considered. From this study, it could be concluded that the galvanic currents are sensitive to the various parameters following a trend similar to that of the Rp values. A relationship between the galvanic and the corrosion current densities was obtained and the limiting values of the Igal, indicative of the state condition of the reinforcing steel for the designed sensor, were established. PMID:22291514

How much work-related injury and illness is missed by the current national surveillance system?

PubMed

Rosenman, Kenneth D; Kalush, Alice; Reilly, Mary Jo; Gardiner, Joseph C; Reeves, Mathew; Luo, Zhewui

2006-04-01

We sought to estimate the undercount in the existing national surveillance system of occupational injuries and illnesses. Adhering to the strict confidentiality rules of the U.S. Bureau of Labor Statistics, we matched the companies and individuals who reported work-related injuries and illnesses to the Bureau in 1999, 2000, and 2001 in Michigan with companies and individuals reported in four other Michigan data bases, workers' compensation, OSHA Annual Survey, OSHA Integrated Management Information System, and the Occupational Disease Report. We performed capture-recapture analysis to estimate the number of cases missed by the combined systems. We calculated that the current national surveillance system did not include 61% and with capture-recapture analysis up to 68% of the work-related injuries and illnesses that occurred annually in Michigan. This was true for injuries alone, 60% and 67%, and illnesses alone 66% and 69%, respectively. The current national system for work-related injuries and illnesses markedly underestimates the magnitude of these conditions. A more comprehensive system, such as the one developed for traumatic workplace fatalities, that is not solely dependent on employer based data sources is needed to better guide decision-making and evaluation of public health programs to reduce work-related conditions.

Proactive interference and practice effects in visuospatial working memory span task performance.

PubMed

Blalock, Lisa Durrance; McCabe, David P

2011-01-01

In the current study the influence of proactive interference (PI) and practice on recall from a visuospatial working memory (WM) task was examined. Participants completed a visuospatial WM span task under either high-PI conditions (a traditional span task) or low-PI conditions (a span task with breaks between trials). Trials of each length (i.e., two to five to-be-remembered items) were equally distributed across three blocks in order to examine practice effects. Recall increased across blocks to a greater extent in the low-PI condition than in the high-PI condition, indicating that reducing PI increased recall from WM. Additionally, in the final block the correlation between fluid intelligence and WM recall was stronger for the high-PI condition than the low-PI condition, indicating that practice reduced the strength of the correlation between span task recall and fluid intelligence, but only in the low-PI condition. These results support current theories that propose that one source of variability in recall from WM span task is the build-up of PI, and that PI build-up is an important contributing factor to the relation between visuospatial WM span task recall and higher-level cognition.

Spatial interpolation of forest conditions using co-conditional geostatistical simulation

Treesearch

H. Todd Mowrer

2000-01-01

In recent work the author used the geostatistical Monte Carlo technique of sequential Gaussian simulation (s.G.s.) to investigate uncertainty in a GIS analysis of potential old-growth forest areas. The current study compares this earlier technique to that of co-conditional simulation, wherein the spatial cross-correlations between variables are included. As in the...

An examination of retention factors among registered nurses in Northeastern Ontario, Canada: Nurses intent to stay in their current position.

PubMed

Nowrouzi, Behdin; Rukholm, Ellen; Lariviere, Michel; Carter, Lorraine; Koren, Irene; Mian, Oxana; Giddens, Emilia

2016-03-10

The purpose of the study was to examine factors related to the retention of registered nurses in northeastern Ontario, Canada. A cross-sectional survey of registered nurses working in northeastern Ontario, Canada was conducted. Logistic regression analyses were used to consider intent to stay in current employment in relation to the following: 1) demographic factors, and 2) occupation and career satisfaction factors. A total of 459 (29.8% response rate) questionnaires were completed. The adjusted odds logistic regression analysis of RNs who intended to remain in their current position for the next five years, demonstrated that respondents in the 46 to 56 age group (OR: 2.65; 95% CI: 1.50 to 4.69), the importance of staff development in the organization (OR: 3.04; 95% CI: 1.13 to 8.13) northeastern Ontario lifestyle (OR: 2.61; 95% CI: 1.55 to 4.40), working in nursing for 14 to 22.5 years (OR: 2.55; 95% CI: 1.10 to 5.93), and working between 0 to 1 hour of overtime per week (OR: 1.20; 95% CI: 1.20 to 4.64) were significant factors in staying in their current position for the next five years. This study shows that a further understanding of the work environment could assist with developing retention for rural nurses. Furthermore, employers may use such information to ameliorate the working conditions of nurses, while researchers may use such evidence to develop interventions that are applicable to improving the working conditions of nurses.

Postsecondary Faculty: Life and Work in the People's Republic of China.

ERIC Educational Resources Information Center

Smith, Harold A.

Current working conditions of postsecondary faculty in the People's Republic of China are described, with a focus on what has changed since 1976 and the end of the Cultural Revolution. Based on field work in China and on personal correspondence with Chinese faculty members between 1984 and 1989, a broad overview is presented of college and…

Current conserving theory at the operator level

NASA Astrophysics Data System (ADS)

Yuan, Jiangtao; Wang, Yin; Wang, Jian

The basic assumption of quantum transport in mesoscopic systems is that the total charge inside the scattering region is zero. This means that the potential deep inside reservoirs is effectively screened and therefore the electric field at interface of scattering region is zero. Thus the current conservation condition can be satisfied automatically which is an important condition in mesoscopic transport. So far the current conserving ac theory is well developed by considering the displacement current which is due to Coulomb interaction if we just focus on the average current. However, the frequency dependent shot noise does not satisfy the conservation condition since we do not consider the current conservation at the operator level. In this work, we formulate a generalized current conserving theory at the operator level using non-equilibrium Green's function theory which could be applied to both average current and frequency dependent shot noise. A displacement operator is derived for the first time so that the frequency dependent correlation of displacement currents could be investigated. Moreover, the equilibrium shot noise is investigated and a generalized fluctuation-dissipation relationship is presented.

Material condition assessment with eddy current sensors

NASA Technical Reports Server (NTRS)

Goldfine, Neil J. (Inventor); Washabaugh, Andrew P. (Inventor); Sheiretov, Yanko K. (Inventor); Schlicker, Darrell E. (Inventor); Lyons, Robert J. (Inventor); Windoloski, Mark D. (Inventor); Craven, Christopher A. (Inventor); Tsukernik, Vladimir B. (Inventor); Grundy, David C. (Inventor)

2010-01-01

Eddy current sensors and sensor arrays are used for process quality and material condition assessment of conducting materials. In an embodiment, changes in spatially registered high resolution images taken before and after cold work processing reflect the quality of the process, such as intensity and coverage. These images also permit the suppression or removal of local outlier variations. Anisotropy in a material property, such as magnetic permeability or electrical conductivity, can be intentionally introduced and used to assess material condition resulting from an operation, such as a cold work or heat treatment. The anisotropy is determined by sensors that provide directional property measurements. The sensor directionality arises from constructs that use a linear conducting drive segment to impose the magnetic field in a test material. Maintaining the orientation of this drive segment, and associated sense elements, relative to a material edge provides enhanced sensitivity for crack detection at edges.

Evaluation of candidate working fluid formulations for the electrothermal-chemical wind tunnel

NASA Technical Reports Server (NTRS)

Akyurtlu, Jale F.; Akyurtlu, Ates

1993-01-01

A new hypersonic test facility which can simulate conditions typical of atmospheric flight at Mach numbers up to 20 is currently under study at the NASA/LaRC Hypersonic Propulsion Branch. In the proposed research, it was suggested that a combustion augmented electrothermal wind tunnel concept may be applied to the planned hypersonic testing facility. The purpose of the current investigation is to evaluate some candidate working fluid formulations which may be used in the chemical-electrothermal wind. The efforts in the initial phase of this research were concentrated on acquiring the code used by GASL to model the electrothermal wind tunnel and testing it using the conditions of GASL simulation. The early version of the general chemical kinetics code (GCKP84) was obtained from NASA and the latest updated version of the code (LSENS) was obtained from the author Dr. Bittker. Both codes are installed on a personal computer with a 486 25 MHz processor and 16 Mbyte RAM. Since the available memory was not sufficient to debug LSENS, for the current work GCKP84 was used.

Design and application of air-conditioning suit based on eddy current cooling principle for distribution network working with power uninterrupted

NASA Astrophysics Data System (ADS)

Xu, Li; Liu, Lanlan; Niu, Jie; Tang, Li; Li, Jinliang; Zhou, Zhanfan; Long, Chenhai; Yang, Qi; Yi, Ziqi; Guo, Hao; Long, Yang; Fu, Yanyi

2017-05-01

As social requirement of power supply reliability keeps rising, distribution network working with power uninterrupted has been widely carried out, while the high - temperature operating environment in summer can easily lead to physical discomfort for the operators, and then lead to safety incidents. Aiming at above problem, air-conditioning suit for distribution network working with power uninterrupted has been putted forward in this paper, and the structure composition and cooling principle of which has been explained, and it has been ultimately put to on-site application. The results showed that, cooling effect of air-conditioning suits was remarkable, and improved the working environment for the operators effectively, which is of great significance to improve Chinese level of working with power uninterrupted, reduce the probability of accidents and enhance the reliability of power supply.

Conducting polymer actuators: From basic concepts to proprioceptive systems

NASA Astrophysics Data System (ADS)

Martinez Gil, Jose Gabriel

Designers and engineers have been dreaming for decades of motors sensing, by themselves, working and surrounding conditions, as biological muscles do originating proprioception. Here bilayer full polymeric artificial muscles were checked up to very high cathodic potential limits (-2.5 V) in aqueous solution by cyclic voltammetry. The electrochemical driven exchange of ions from the conducting polymer film, and the concomitant Faradaic bending movement of the muscle, takes place in the full studied potential range. The presence of trapped counterion after deep reduction was corroborated by EDX determinations giving quite high electronic conductivity to the device. The large bending movement was used as a tool to quantify the amount of water exchanged per reaction unit (exchanged electron or ion). The potential evolutions of self-supported films of conducting polymers or conducting polymers (polypyrrole, polyaniline) coating different microfibers, during its oxidation/reduction senses working mechanical, thermal, chemical or electrical variables. The evolution of the muscle potential from electrochemical artificial muscles based on electroactive materials such as intrinsically conducting polymers and driven by constant currents senses, while working, any variation of the mechanical (trailed mass, obstacles, pressure, strain or stress), thermal or chemical conditions of work. One physically uniform artificial muscle includes one electrochemical motor and several sensors working simultaneously under the same driving reaction. Actuating (current and charge) and sensing (potential and energy) magnitudes are present, simultaneously, in the only two connecting wires and can be read by the computer at any time. From basic polymeric, mechanical and electrochemical principles a physicochemical equation describing artificial proprioception has been developed. It includes and describes, simultaneously, the evolution of the muscle potential during actuation as a function of the motor characteristics (rate and sense of the movement, relative position, and required energy) and the working variables (temperature, electrolyte concentration, mechanical conditions and driving current). By changing working conditions experimental results overlap theoretical predictions. The ensemble computer-generator-muscle-theoretical equation constitutes and describes artificial mechanical, thermal and chemical proprioception of the system. Proprioceptive tools and most intelligent zoomorphic or anthropomorphic soft robots can be envisaged.

Electrochemical characterization and control of triple-layer muscles

NASA Astrophysics Data System (ADS)

Otero, Toribio F.; Cortes, Maria T.

2000-06-01

The electrochemical characterization of triple-layers formed by a EPA (Electroactive Polymer)/double-sided tape/EPA, like artificial muscles is described. Those muscles were characterized working under constant potential or under constant current. Due to the electrochemical nature of the electrochemomechanical property, muscles working under constant current produce constant movements, consuming increasing energies at decreasing temperatures, decreasing concentrations of electrolytes or trailing increasing masses. Muscles working at constant potential response with a faster movement if the temperature or the concentration of the electrolyte increase, or if the trailed weight decreases. Specific charges and specific energies were determined for every experimental condition.

Training, Research, and Working Conditions for Urology Residents in Germany: A Contemporary Survey.

PubMed

Borgmann, Hendrik; Arnold, Hannah K; Meyer, Christian P; Bründl, Johannes; König, Justus; Nestler, Tim; Ruf, Christian; Struck, Julian; Salem, Johannes

2016-12-16

Excellent uniform training of urology residents is crucial to secure both high-quality patient care and the future of our specialty. Residency training has come under scrutiny following the demands of subspecialized care, economical aspects, and working hour regulations. To comprehensively assess the surgical training, research opportunities, and working conditions among urology residents in Germany. We sent a 29-item online survey via email to 721 members of the German Society of Residents in Urology. Descriptive analyses were conducted to describe the surveys' four domains: (1) baseline characteristics, (2) surgical training (cumulative completed case volume for all minor-, medium-, and major-complexity surgeries), (3) research opportunities, and (4) working conditions. Four hundred and seventy-two residents completed the online survey (response rate 65%). Surgical training: the median number of cumulative completed cases for postgraduate yr (PGY)-5 residents was 113 (interquartile range: 76-178). Minor surgeries comprised 57% of all surgeries and were performed by residents in all PGYs. Medium-complexity surgeries comprised 39% of all surgeries and were mostly performed by residents in PGYs 2-5. Major surgeries comprised 4% of all surgeries and were occasionally performed by residents in PGYs 3-5. Research opportunities: some 44% have attained a medical thesis (Dr. med.), and 39% are currently pursuing research. Working conditions: psychosocial work-related stress was high and for 82% of residents their effort exceeded their rewards. Some 44% were satisfied, 32% were undecided, and 24% were dissatisfied with their current working situation. Limitations include self-reported survey answers and a lack of validated assessment tools. Surgical exposure among German urology residents is low and comprises minor and medium-complex surgeries. Psychosocial work-related stress is high for the vast majority of residents indicating the need for structural improvements in German urology residency training. In this study, we evaluated the surgical training, research opportunities, and working conditions among urology residents in Germany. We found low surgical exposure and high rates for psychosocial work-related stress, indicating the need for structural improvements in German urology residency training. Copyright © 2016 European Association of Urology. Published by Elsevier B.V. All rights reserved.

Interim MELCOR Simulation of the Fukushima Daiichi Unit 2 Accident Reactor Core Isolation Cooling Operation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ross, Kyle W.; Gauntt, Randall O.; Cardoni, Jeffrey N.

2013-11-01

Data, a brief description of key boundary conditions, and results of Sandia National Laboratories’ ongoing MELCOR analysis of the Fukushima Unit 2 accident are given for the reactor core isolation cooling (RCIC) system. Important assumptions and related boundary conditions in the current analysis additional to or different than what was assumed/imposed in the work of SAND2012-6173 are identified. This work is for the U.S. Department of Energy’s Nuclear Energy University Programs fiscal year 2014 Reactor Safety Technologies Research and Development Program RC-7: RCIC Performance under Severe Accident Conditions.

Structures, Compositions, and Activities of Live Shewanella Biofilms Formed on Graphite Electrodes in Electrochemical Flow Cells

PubMed Central

Kitayama, Miho; Koga, Ryota; Kasai, Takuya; Kouzuma, Atsushi

2017-01-01

ABSTRACT An electrochemical flow cell equipped with a graphite working electrode (WE) at the bottom was inoculated with Shewanella oneidensis MR-1 expressing an anaerobic fluorescent protein, and biofilm formation on the WE was observed over time during current generation at WE potentials of +0.4 and 0 V (versus standard hydrogen electrodes), under electrolyte-flow conditions. Electrochemical analyses suggested the presence of unique electron-transfer mechanisms in the +0.4-V biofilm. Microscopic analyses revealed that, in contrast to aerobic biofilms, current-generating biofilm (at +0.4 V) was thin and flat (∼10 μm in thickness), and cells were evenly and densely distributed in the biofilm. In contrast, cells were unevenly distributed in biofilm formed at 0 V. In situ fluorescence staining and biofilm recovery experiments showed that the amounts of extracellular polysaccharides (EPSs) in the +0.4-V biofilm were much smaller than those in the aerobic and 0-V biofilms, suggesting that Shewanella cells suppress the production of EPSs at +0.4 V under flow conditions. We suggest that Shewanella cells perceive electrode potentials and modulate the structure and composition of biofilms to efficiently transfer electrons to electrodes. IMPORTANCE A promising application of microbial fuel cells (MFCs) is to save energy in wastewater treatment. Since current is generated in these MFCs by biofilm microbes under horizontal flows of wastewater, it is important to understand the mechanisms for biofilm formation and current generation under water-flow conditions. Although massive work has been done to analyze the molecular mechanisms for current generation by model exoelectrogenic bacteria, such as Shewanella oneidensis, limited information is available regarding the formation of current-generating biofilms over time under water-flow conditions. The present study developed electrochemical flow cells and used them to examine the electrochemical and structural features of current-generating biofilms under water-flow conditions. We show unique features of mature biofilms actively generating current, creating opportunities to search for as-yet-undiscovered current-generating mechanisms in Shewanella biofilms. Furthermore, information provided in the present study is useful for researchers attempting to develop anode architectures suitable for wastewater treatment MFCs. PMID:28625998

Structures, Compositions, and Activities of Live Shewanella Biofilms Formed on Graphite Electrodes in Electrochemical Flow Cells.

PubMed

Kitayama, Miho; Koga, Ryota; Kasai, Takuya; Kouzuma, Atsushi; Watanabe, Kazuya

2017-09-01

An electrochemical flow cell equipped with a graphite working electrode (WE) at the bottom was inoculated with Shewanella oneidensis MR-1 expressing an anaerobic fluorescent protein, and biofilm formation on the WE was observed over time during current generation at WE potentials of +0.4 and 0 V (versus standard hydrogen electrodes), under electrolyte-flow conditions. Electrochemical analyses suggested the presence of unique electron-transfer mechanisms in the +0.4-V biofilm. Microscopic analyses revealed that, in contrast to aerobic biofilms, current-generating biofilm (at +0.4 V) was thin and flat (∼10 μm in thickness), and cells were evenly and densely distributed in the biofilm. In contrast, cells were unevenly distributed in biofilm formed at 0 V. In situ fluorescence staining and biofilm recovery experiments showed that the amounts of extracellular polysaccharides (EPSs) in the +0.4-V biofilm were much smaller than those in the aerobic and 0-V biofilms, suggesting that Shewanella cells suppress the production of EPSs at +0.4 V under flow conditions. We suggest that Shewanella cells perceive electrode potentials and modulate the structure and composition of biofilms to efficiently transfer electrons to electrodes. IMPORTANCE A promising application of microbial fuel cells (MFCs) is to save energy in wastewater treatment. Since current is generated in these MFCs by biofilm microbes under horizontal flows of wastewater, it is important to understand the mechanisms for biofilm formation and current generation under water-flow conditions. Although massive work has been done to analyze the molecular mechanisms for current generation by model exoelectrogenic bacteria, such as Shewanella oneidensis , limited information is available regarding the formation of current-generating biofilms over time under water-flow conditions. The present study developed electrochemical flow cells and used them to examine the electrochemical and structural features of current-generating biofilms under water-flow conditions. We show unique features of mature biofilms actively generating current, creating opportunities to search for as-yet-undiscovered current-generating mechanisms in Shewanella biofilms. Furthermore, information provided in the present study is useful for researchers attempting to develop anode architectures suitable for wastewater treatment MFCs. Copyright © 2017 American Society for Microbiology.

The Rated Voltage Determination of DC Building Power Supply System Considering Human Beings Safety

NASA Astrophysics Data System (ADS)

Wang, Zhicheng; Yu, Kansheng; Xie, Guoqiang; Zou, Jin

2018-01-01

Generally two-level voltages are adopted for DC building power supply system. From the point of view of human beings safety, only the lower level voltage which may be contacted barehanded is discussed in this paper based on the related safety thresholds of human beings current effect. For several voltage levels below 100V recommended by IEC, the body current and current density of human electric shock under device normal work condition, as well as effect of unidirectional single impulse currents of short durations are calculated and analyzed respectively. Finally, DC 60V is recommended as the lower level rating voltage through the comprehensive consideration of technical condition and cost of safety criteria.

Creative Environment Formation in Design Professional Training

ERIC Educational Resources Information Center

Zakirova, Venera G.; Purik, Elza E.

2016-01-01

The current interest to the issue of this work lies in the fact that a professional competence of a designer needs highly developed abilities to create new and different projects of high aesthetic value in compliance with the current regulations. Image visualization abilities development needs special conditions encouraging personal creativity.…

Work-related reproductive, musculoskeletal and mental disorders among working women--history, current issues and future research directions.

PubMed

Kishi, Reiko; Kitahara, Teruyo; Masuchi, Ayumi; Kasai, Setsuko

2002-04-01

According to the recent changes of working environments and socio-economical conditions, the proportion of working women are increasing in Japan. Characteristics of occupational workload and stress of Japanese working women are consistent with those in many industrialized countries except man-dominant culture. In this review we describe the history, current issues, and future research directions on occupational health of working women, especially focused on reproductive health, work-related musculo-skeletal disorders (WMSDs), and mental disorders. In the reproductive health survey, traditionally main concern was about pregnancy outcomes, then fecundity studies, such as time to pregnancy, became topics recently. Future research will be shifted to outcomes not only during pregnancy but also disorders of hormonal balance and climacterium or health conditions after menopause. WMSDs are reviewed on mainly gender difference and its causative factors. Historically, mental health of working women in Japan has focused on the job stress of nurses. We compare results with a lot of recent researches in Europe and U.S.A., where interaction between occupational stress and family roles were studied. It is not easy to predict the prospective status of female workers in Japan, but social, workplace and familial supports will enhance their health promotion.

Ageing, working hours and work ability.

PubMed

Costa, G; Sartori, S

2007-11-01

The current paper reports the main results of several studies carried out on Italian workers using the work ability index as a complementary tool for workers' periodical health surveillance. The work ability index shows a general decreasing trend over the years, but it changes differently according to working conditions and personal health status. In jobs with higher mental involvement and autonomy, but lower physical constraint, it remains quite constant and high over the years, while it significantly decreases with a steeper trend the higher the physical work load and the lower the job control are. Sex and working hours appear to act concurrently in influencing work ability, particularly in association with more physically demanding jobs. It is therefore necessary to adopt flexible interventions, able to give ageing shift workers a proper support for maintaining a satisfactory work ability, by means of actions addressed both to work organization and psycho-physical conditions.

Improving Scientific Inquiry for Social Work in South Korea: The Center for Social Welfare Research at Yonsei University

ERIC Educational Resources Information Center

Choi, Jae-Sung; Choi, Soochan; Kim, Yujin

2009-01-01

This article examines current social issues and welfare needs in South Korea and discusses societal efforts to respond to these needs through social welfare systems nationwide. It also reviews how social work scholars, major contributors to the creation of a Korean welfare state, have contributed to the conditions of social work practice by…

Language and Society in South Asia. Final Report.

ERIC Educational Resources Information Center

Shapiro, Michael C.; Schiffman, Harold F.

This work attempts to provide an overview of linguistic diversity in South Asia and to place this diversity in a cultural context. The work tries to describe the current state of knowledge concerning socially conditioned language variation in the subcontinent. Each of five major language families contains numerous mutually intelligible and…

Study of influence of various factors on electrochemical signal of lead in water solutions

NASA Astrophysics Data System (ADS)

Zhikharev, Yu N.; Andrianova, L. I.; Ogudova, E. V.

2018-05-01

The conditions for obtaining a reproducible signal of lead in water solutions of indifferent electrolytes on various substrates (working electrodes) for analytical purposes were studied. Attention was also paid to studying the regularities of the initial stage of formation of lead sediments by the method of inversion voltammetry. The possibility of using different working electrodes to obtain stable current-potential curves is shown depending on the conditions of electrolysis, pH of the medium, the electrolysis potential and impurities.

Anode current density distribution in a cusped field thruster

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Huan, E-mail: wuhuan58@qq.com; Liu, Hui, E-mail: hlying@gmail.com; Meng, Yingchao

2015-12-15

The cusped field thruster is a new electric propulsion device that is expected to have a non-uniform radial current density at the anode. To further study the anode current density distribution, a multi-annulus anode is designed to directly measure the anode current density for the first time. The anode current density decreases sharply at larger radii; the magnitude of collected current density at the center is far higher compared with the outer annuli. The anode current density non-uniformity does not demonstrate a significant change with varying working conditions.

Work function measurements during plasma exposition at conditions relevant in negative ion sources for the ITER neutral beam injection.

PubMed

Gutser, R; Wimmer, C; Fantz, U

2011-02-01

Cesium seeded sources for surface generated negative hydrogen ions are major components of neutral beam injection systems in future large-scale fusion experiments such as ITER. The stability and delivered current density depend highly on the work function during vacuum and plasma phases of the ion source. One of the most important quantities that affect the source performance is the work function. A modified photocurrent method was developed to measure the temporal behavior of the work function during and after cesium evaporation. The investigation of cesium exposed Mo and MoLa samples under ITER negative hydrogen ion based neutral beam injection relevant surface and plasma conditions showed the influence of impurities which result in a fast degradation when the plasma exposure or the cesium flux onto the sample is stopped. A minimum work function close to that of bulk cesium was obtained under the influence of the plasma exposition, while a significantly higher work function was observed under ITER-like vacuum conditions.

[Scoping review about working conditions and health of immigrant workers in Spain].

PubMed

Ronda-Pérez, Elena; Agudelo-Suárez, Andrés A; López-Jacob, María José; García, Ana M; Benavides, Fernando G

2014-01-01

The relationship between immigration, work, and health is one of the most important challenges in occupational health at current, particularly in Spain, by the significant increase in the migrant workers in the labor market occurred. This investigation aims to know the relationship betwen working conditions and their effects on migrant workers. Scoping review of scientific papers on this topic at the Medline and Medes databases in Spanish and English (1998-2012). The articles included were full text reviewed. 20 studies were included, 13 with quantitative methodology and 7 qualitative. The topics address specific health problems related to work (primarily occupational accidents), disability, and differences in working conditions and employment. The findings of the studies show a higher incidence of injury accidents, lower rates of disability, higher prevalence of work presenteeism, exposure to psychosocial factors, and precariousness. Despite the uniqueness of the demographic process migration happened in Spain, health problems and determinants identified no different from those referenced in other countries, in other contexts and in other times.

Medical registrars in 2010: experience and expectations of the future consultant physicians of the UK.

PubMed

Goddard, Andrew F; Evans, Timothy; Phillips, Christopher

2011-12-01

In 2010, 2,176 medical registrars in England (43%) responded to a survey of attitudes to current and future working conditions. Regarding current working, 88% were currently happy with their job with respect to their specialty but only 49% were happy with respect to acute medicine. Even if pay was increased, 59% would only want to work a 48-hour week or less. Regarding future jobs, 59% were worried about future job prospects with 91% exploring ways of extending their training. Only 36% would consider working away from their current location as a consultant, only 42% of those trained in acute medicine wish to take part in the acute take, 15% would consider a 'sub-consultant' post and only 60% were looking forward to becoming a consultant. The findings of this survey show that medical registrars are very concerned about their future. From their perspective, clinical medicine in England is in poor health.

[Distress and job satisfaction among hospital physicians in internal medicine].

PubMed

Bauer, J; Groneberg, D A

2014-10-01

How physicians within the specialty of internal medicine perceive their stress-related working conditions, especially due to a changing health system with an impact on workflows and working hours, is examined in this study. A total of 1696 online questionnaires completed by internists were analyzed. The questionnaire was based upon the Effort-Reward Imbalance (ERI) model by Siegrist et al. and the Job-Demand-Control model (JDC) by Karasek et al. Working conditions in the specialty of internal medicine seem to have a high risk of leading to distress. As a result 62.1 % [95 % confidence interval (CI): 59.8-64.5] of the respondents described working conditions with unfavorable stress (distress). Analyzing the distress prevalence in subgroups, there were significant differences between gender (65.9 % of female physicians and 58.6 % of male physicians; p = 0.002; odds ratio (OR): 1.37; 95 % CI: 1.12-1.66), age (69.3 % of under 35-year-old to 56.6 % of 35- to 59-year-old), and functional position (38.3 % of chief physician to 69.1 % of junior physicians; OR: 7.17; 95 % CI: 3.91-13.16). Regarding job satisfaction 48.1 % of respondents said, they were very satisfied with their job. This study should be a cause for concern, since current data suggest a future shortage of qualified employers in the specialty of internal medicine. Taking this into account, working conditions in hospitals should be improved in order to bind current employees and attract new employees.

Damage and annealing recovery of boron-implanted ultra-shallow junction: The correlation between beam current and surface configuration

NASA Astrophysics Data System (ADS)

Chang, Feng-Ming; Wu, Zong-Zhe; Lin, Yen-Fu; Kao, Li-Chi; Wu, Cheng-Ta; JangJian, Shiu-Ko; Chen, Yuan-Nian; Lo, Kuang Yao

2018-03-01

The condition of the beam current in the implantation process is a key issue in the damage rate and structural evolution in the sequent annealing process, especially for ultra-shallow layers. In this work, we develop a compensative optical method combined with UV Raman, X-ray photoelectron spectroscopy (XPS), and X-ray absorption near edge spectroscopy (XANES) to inspect the influence of the beam current in the implantation process. The optima condition of the beam current in the implantation process is determined by higher effective Si-B bond portion in UV Raman spectra and less the peak of B-B bond in XPS spectra which is caused by B cluster defects. Results of XANES indicate that the B oxide layer is formed on the surface of the ultra-shallow junction. The defects in the ultra-shallow junction after annealing are analyzed by novel optical analyses, which cannot be inspected by a traditional thermal wave and resistance measurement. This work exhibits the structural variation of the ultra-shallow junction via a variant beam current and provides a valuable metrology in examining the chemical states and the effective activation in the implantation technology.

Low-Arousal Speech Noise Improves Performance in N-Back Task: An ERP Study

PubMed Central

Zhang, Dandan; Jin, Yi; Luo, Yuejia

2013-01-01

The relationship between noise and human performance is a crucial topic in ergonomic research. However, the brain dynamics of the emotional arousal effects of background noises are still unclear. The current study employed meaningless speech noises in the n-back working memory task to explore the changes of event-related potentials (ERPs) elicited by the noises with low arousal level vs. high arousal level. We found that the memory performance in low arousal condition were improved compared with the silent and the high arousal conditions; participants responded more quickly and had larger P2 and P3 amplitudes in low arousal condition while the performance and ERP components showed no significant difference between high arousal and silent conditions. These findings suggested that the emotional arousal dimension of background noises had a significant influence on human working memory performance, and that this effect was independent of the acoustic characteristics of noises (e.g., intensity) and the meaning of speech materials. The current findings improve our understanding of background noise effects on human performance and lay the ground for the investigation of patients with attention deficits. PMID:24204607

Sensing and Tactile Artificial Muscles from Reactive Materials

PubMed Central

Conzuelo, Laura Valero; Arias-Pardilla, Joaquín; Cauich-Rodríguez, Juan V.; Smit, Mascha Afra; Otero, Toribio Fernández

2010-01-01

Films of conducting polymers can be oxidized and reduced in a reversible way. Any intermediate oxidation state determines an electrochemical equilibrium. Chemical or physical variables acting on the film may modify the equilibrium potential, so that the film acts as a sensor of the variable. The working potential of polypyrrole/DBSA (Dodecylbenzenesulfonic acid) films, oxidized or reduced under constant currents, changes as a function of the working conditions: electrolyte concentration, temperature or mechanical stress. During oxidation, the reactive material is a sensor of the ambient, the consumed electrical energy being the sensing magnitude. Devices based on any of the electrochemical properties of conducting polymers must act simultaneously as sensors of the working conditions. Artificial muscles, as electrochemical actuators constituted by reactive materials, respond to the ambient conditions during actuation. In this way, they can be used as actuators, sensing the surrounding conditions during actuation. Actuating and sensing signals are simultaneously included by the same two connecting wires. PMID:22319265

Musculoskeletal pain in the workforce: the effects of back, arthritis, and fibromyalgia pain on quality of life and work productivity.

PubMed

McDonald, Margaret; DiBonaventura, Marco daCosta; Ullman, Stacey

2011-07-01

To investigate the impact of musculoskeletal pain on health-related quality of life and work productivity losses among US workers. Data from the 2008 US National Health and Wellness Survey were used. Among those currently employed aged 20 to 64 years (N = 30,868), workers with arthritis (n = 2,670), back (n = 4,920), and fibromyalgia (n = 439) pain were compared with workers without those respective musculoskeletal pain conditions. Arthritis, back, and fibromyalgia pain were all associated with significantly lower levels of health-related quality of life, often at clinically meaningful levels. All pain conditions were associated with higher levels of work productivity loss, even after adjusting for demographic and health characteristics. Musculoskeletal pain conditions were highly prevalent and associated with a significant burden. Improved management of these conditions may lead to improved productivity, benefiting both employers and workers alike.

The Development of Verbal and Visual Working Memory Processes: A Latent Variable Approach

ERIC Educational Resources Information Center

Koppenol-Gonzalez, Gabriela V.; Bouwmeester, Samantha; Vermunt, Jeroen K.

2012-01-01

Working memory (WM) processing in children has been studied with different approaches, focusing on either the organizational structure of WM processing during development (factor analytic) or the influence of different task conditions on WM processing (experimental). The current study combined both approaches, aiming to distinguish verbal and…

Designing and Developing a Work Experience Component for a Vocational Education Curriculum.

ERIC Educational Resources Information Center

Santos, Otto, Jr.; Olinzock, Anthony

A work experience component for vocational educator teacher education based on demonstrated competence is proposed. Its basis is research concerning vocational education; sociometric conditions and needs; analyses of the past, present, and future of vocational education; and the current state of the art relative to curriculum systems. This…

Renovation of the fixing and loading factors of the beam by the spectral data of free flexural vibrations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Akhymbek, Meiram Erkanatuly; Yessirkegenov, Nurgissa Amankeldiuly; Sadybekov, Makhmud Abdysametovich

2015-09-18

In the current paper, the problem of bending vibrations of a beam in which the binding on the right end is unknown and not available for visual inspection is studied. The main objective is to study an inverse problem: find additional unknown boundary conditions by additional spectral data, i.e., the conditions of fixing the right end of the rod. In this work, unlike many other works, as such additional conditions we choose the first natural frequencies (eigenvalues) of two new problems corresponding to the problem of bending vibrations of a beam with loads of different weights at the central point.

Results of hydrotreating the kerosene fraction of HTI`S first proof of concept run

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stohl, F.V.; Lott, S.E.; Diegert, K.V.

1996-06-01

The objective of Sandia`s hydrotreating study is to determine the relationships between hydrotreating conditions and product characteristics for coal liquids produced using current technologies. The coal-derived liquid used in the current work is the kerosene fraction of the product from Hydrocarbon Technologies Inc.`s first proof-of-concept run for it`s Catalytic Two-Stage Liquefaction Technology. Sandia`s hydrotreating experiments were performed in a continuous operation, microflow reactor system using aged HDN-60 catalyst. A factorial experimental design with three variables (temperature, pressure, liquid hourly space velocity) was used in this work. Nitrogen and sulfur contents of the feed and hydrotreated products were determined using anmore » Antek 7000 Sulfur and Nitrogen Analyzer. Multiple samples were collected at each set of reaction conditions to ensure that each condition was lined out. Hydrotreating at each set of reaction conditions was repeated so that results could be normalized for catalyst deactivation. The normalized results were statistically analyzed. Increases in temperature and pressure had the greatest effects on nitrogen removal. The highest severity condition (388{degrees}C, 1500 psig H{sub 2}, 1.5g/h/g(cat)) gave a measured nitrogen value of <5 ppm.« less

Results of hydrotreating the kerosene fraction of HTI`S first proof of concept run

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stohl, F.V.; Lott, S.E.; Diegert, K.V.

1996-12-31

The objective of Sandia`s hydrotreating study is to determine the relationships between hydrotreating conditions and product characteristics for coal liquids produced using current technologies. The coal-derived liquid used in the current work is the kerosene fraction of the product from Hydrocarbon Technologies Inc.`s first proof-of-concept run for it`s Catalytic Two-Stage Liquefaction Technology. Sandia`s hydrotreating experiments were performed in a continuous operation, microflow reactor system using aged HDN-60 catalyst. A factorial experimental design with three variables (temperature, pressure, liquid hourly space velocity) was used in this work. Nitrogen and sulfur contents of the feed and hydrotreated products were determined using anmore » Antek 7000 Sulfur and Nitrogen Analyzer. Multiple samples were collected at each set of reaction conditions to ensure that each condition was lined out. Hydrotreating at each set of reaction conditions was repeated so that results could be normalized for catalyst deactivation. The normalized results were statistically analyzed. Increases in temperature and pressure had the greatest effects on nitrogen removal. The highest severity condition (388{degrees}C, 1500 psig H{sub 2}, 1.5g/h/g(cat)) gave a measured nitrogen value of <5 ppm.« less

Education for Tomorrow.

ERIC Educational Resources Information Center

Blackstone, Tessa

1983-01-01

Implications of current social and economic conditions in Britain for educational planning are considered and some recommendations made addressing problems of disadvantaged youth, women, the industrial work force, and the retired and unemployed. (MJL)

Comparison the Results of Numerical Simulation And Experimental Results for Amirkabir Plasma Focus Facility

NASA Astrophysics Data System (ADS)

Goudarzi, Shervin; Amrollahi, R.; Niknam Sharak, M.

2014-06-01

In this paper the results of the numerical simulation for Amirkabir Mather-type Plasma Focus Facility (16 kV, 36μF and 115 nH) in several experiments with Argon as working gas at different working conditions (different discharge voltages and gas pressures) have been presented and compared with the experimental results. Two different models have been used for simulation: five-phase model of Lee and lumped parameter model of Gonzalez. It is seen that the results (optimum pressures and current signals) of the Lee model at different working conditions show better agreement than lumped parameter model with experimental values.

Economic Ergonomic Approach to Design an Optimal Manpower and Mechanization in Rice Production

NASA Astrophysics Data System (ADS)

Muanah; Syuaib, M. F.; Liyantono

2018-05-01

Productivity of manpower could be improved by considering the economic and ergonomic aspect. The ergonomic aspect (human factor) is required to design an optimal manpower, while in the economic aspect, the well being of manpower could be evaluated from the amount of received income based on their work capability. This research was conducted on February 2016 to January 2017 in Gapoktan Silih Asih rice field Cigombong, Bogor. This study aims to analyze the income of manpower based on current conditions, increasement of working hours and mechanization addition. The results showed that manpower income based on the current condition and ergonomic consideration was Rp 1,174,030/person.month, by increasing the working hours with ergonomic consideration the obtained income was Rp 1,766,204/person.month. the revenues were based on the existing work system even though the increasement of working hours have not provided optimal income due to low productivity. Therefore the results of analysis with the addition of selective mechanization, showed self-ownership machinery was more profitable the obtained income have more than the Bogor minimum wage standard of Rp 2,969,325/person.month.

Effect of cold conditions on manual performance while wearing petroleum industry protective clothing.

PubMed

Wiggen, Øystein Nordrum; Heen, Sigri; Færevik, Hilde; Reinertsen, Randi Eidsmo

2011-01-01

The purpose of this study was to investigate manual performance and thermal responses during low work intensity in persons wearing standard protective clothing in the petroleum industry when they were exposed to a range of temperatures (5, -5, -15 and -25℃) that are relevant to environmental conditions for petroleum industry personnel in northern regions. Twelve men participated in the study. Protective clothing was adjusted for the given cold exposure according to current practices. The subjects performed manual tests five times under each environmental condition. The manual performance test battery consisted of four different tests: tactile sensation (Semmes-Weinstein monofilaments), finger dexterity (Purdue Pegboard), hand dexterity (Complete Minnesota dexterity test) and grip strength (grip dynamometer). We found that exposure to -5℃ or colder lowered skin and body temperatures and reduced manual performance during low work intensity. In conclusion the current protective clothing at a given cold exposure is not adequate to maintain manual performance and thermal balance for petroleum workers in the high north.

Quench dynamics of the Josephson current in a topological Josephson junction

NASA Astrophysics Data System (ADS)

Sun, Dihao; Liu, Jie

2018-01-01

The 4 π -periodic Josephson effect is a distinguishing feature of a topological Josephson junction. However, stringent conditions make it hard to observe in experiments. In this work, we study the transient transport properties in a topological Josephson junction numerically. We show that the 4 π Josephson current can be sustained under nonequilibrium conditions. The properties of the Josephson current are analyzed for different conditions and three main regimes are identified. First, when both the superconducting wires of the Josephson junction lie in the topologically nontrivial region, a 4 π Josephson current can appear upon suddenly applying a dc voltage. Second, when one superconducting wire lies in the trivial region, while the other wire lies in the nontrivial region, the Josephson current is 2 π periodic but the component of the higher-order Josephson current increases. Third, when both wires lie in the trivial region, a stable 2 π Josephson current is observed. Most importantly, the fractional Josephson effect is fragile in the presence of disorder. Hence experiments should be designed carefully to eliminate the effect of disorder. These results could be helpful to optimize fine-tuning of the experimental parameters to observe the 4 π -periodic Josephson current in a topological Josephson junction.

One-step electrochemical deposition of Schiff base cobalt complex as effective water oxidation catalyst

NASA Astrophysics Data System (ADS)

Huang, Binbin; Wang, Yan; Zhan, Shuzhong; Ye, Jianshan

2017-02-01

Schiff base metal complexes have been applied in many fields, especially, a potential homogeneous catalyst for water splitting. However, the high overpotential, time consumed synthesis process and complicated working condition largely limit their application. In the present work, a one-step approach to fabricate Schiff base cobalt complex modified electrode is developed. Microrod clusters (MRC) and rough spherical particles (RSP) can be obtained on the ITO electrode through different electrochemical deposition condition. Both of the MRC and RSP present favorable activity for oxygen evolution reaction (OER) compared to the commercial Co3O4, taking an overpotential of 650 mV and 450 mV to drive appreciable catalytic current respectively. The highly active and stable RSP shows a Tafel plot of 84 mV dec-1 and negligible decrease of the current density for 12 h bulk electrolysis. The synthesis strategy of effective and stable catalyst in this work provide a simple method to fabricate heterogeneous OER catalyst with Schiff base metal complex.

Hot-spot heating susceptibility due to reverse bias operating conditions

NASA Technical Reports Server (NTRS)

Gonzalez, C. C.

1985-01-01

Because of field experience (indicating that cell and module degradation could occur as a result of hot spot heating), a laboratory test was developed at JPL to determine hot spot susceptibility of modules. The initial hot spot testing work at JPL formed a foundation for the test development. Test parameters are selected as follows. For high shunt resistance cells, the applied back bias test current is set equal to the test cell current at maximum power. For low shunt resistance cells, the test current is set equal to the cell short circuit current. The shadow level is selected to conform to that which would lead to maximum back bias voltage under the appropriate test current level. The test voltage is determined by the bypass diode frequency. The test conditions are meant to simulate the thermal boundary conditions for 100 mW/sq cm, 40C ambient environment. The test lasts 100 hours. A key assumption made during the development of the test is that no current imbalance results from the connecting of multiparallel cell strings. Therefore, the test as originally developed was applicable for single string case only.

The protective effects of brief mindfulness meditation training.

PubMed

Banks, Jonathan B; Welhaf, Matthew S; Srour, Alexandra

2015-05-01

Mindfulness meditation has gained a great deal of attention in recent years due to the variety of physical and psychological benefits, including improved working memory, decreased mind wandering and reduced impact of stress on working memory. The current study examined a 1-week at home mindfulness meditation intervention compared to an active control intervention. Results suggest that mindfulness meditation does not increase working memory or decrease mind wandering but does prevent stress related working memory impairments. Mindfulness meditation appears to alter the factors that impair working memory such that the negative impact of mind wandering on working memory was only evident at higher levels of negative affect. The use of cognitive mechanism words in narratives of stressful events did not differ by condition but predicted poorer working memory in the control condition. The results support the use of an at home mindfulness meditation intervention for reducing stress-related impairments. Copyright © 2015 Elsevier Inc. All rights reserved.

[Fostering a breastfeeding-friendly workplace].

PubMed

Chen, Yi-Chun; Kuo, Shu-Chen

2013-02-01

Creating supportive environments that encourage mothers to breastfeed their children has emerged in recent years as a key health issue for women and children. Taiwan has a large and still growing number of new mothers in the workplace. Early postpartum return to work and inconvenient workplace conditions often discourage women from breastfeeding or cause early discontinuation. This study describes the current status of worksite breastfeeding-friendly policies in Taiwan and selected other countries and assesses the effects of work-related factors on working mother breastfeeding behavior. Although maternity leave has been positively correlated with breastfeeding duration, maternity leave in Taiwan remains significantly shorter than in other countries. Flexible working conditions, the provision of lactation rooms, and support from colleagues are critical components of promoting breastfeeding in the workplace.

Hematocrit levels as cardiovascular risk among taxi drivers in Bangkok, Thailand

PubMed Central

ISHIMARU, Tomohiro; ARPHORN, Sara; JIRAPONGSUWAN, Ann

2016-01-01

In Thailand, taxi drivers employed in the informal sector often experience hazardous working conditions. Previous studies revealed that elevated Hematocrit (HCT) is a predictor of cardiovascular disease (CVD) risk. This study assessed factors associated with HCT in taxi drivers to predict their occupational CVD risk factors. A cross-sectional study was conducted on 298 male taxi drivers who joined a health check-up campaign in Bangkok, Thailand. HCT and body mass index were retrieved from participant health check-up files. Self-administered questionnaires assessed demographics, driving mileage, working hours, and lifestyle. Statistical associations were analyzed using stepwise linear regression. Our results showed that obesity (p=0.007), daily alcohol drinking (p=0.003), and current or past smoking (p=0.016) were associated with higher HCT levels. While working hours were not directly associated with HCT levels in the current study, the effect on overworking is statistically arguable because most participants worked substantially longer hours. Our findings suggest that taxi drivers’ CVD risk may be increased by their unhealthy work styles. Initiatives to improve general working conditions for taxi drivers should take into account health promotion and CVD prevention. The policy of providing periodic health check-ups is important to make workers in the informal sector aware of their health status. PMID:27151439

Hematocrit levels as cardiovascular risk among taxi drivers in Bangkok, Thailand.

PubMed

Ishimaru, Tomohiro; Arphorn, Sara; Jirapongsuwan, Ann

2016-10-08

In Thailand, taxi drivers employed in the informal sector often experience hazardous working conditions. Previous studies revealed that elevated Hematocrit (HCT) is a predictor of cardiovascular disease (CVD) risk. This study assessed factors associated with HCT in taxi drivers to predict their occupational CVD risk factors. A cross-sectional study was conducted on 298 male taxi drivers who joined a health check-up campaign in Bangkok, Thailand. HCT and body mass index were retrieved from participant health check-up files. Self-administered questionnaires assessed demographics, driving mileage, working hours, and lifestyle. Statistical associations were analyzed using stepwise linear regression. Our results showed that obesity (p=0.007), daily alcohol drinking (p=0.003), and current or past smoking (p=0.016) were associated with higher HCT levels. While working hours were not directly associated with HCT levels in the current study, the effect on overworking is statistically arguable because most participants worked substantially longer hours. Our findings suggest that taxi drivers' CVD risk may be increased by their unhealthy work styles. Initiatives to improve general working conditions for taxi drivers should take into account health promotion and CVD prevention. The policy of providing periodic health check-ups is important to make workers in the informal sector aware of their health status.

AWPA biodeterioration hazard map revisited

Treesearch

Grant T. Kirker; Amy B. Bishell; William J. Hickey

2017-01-01

The fungal decay hazard map used by the American Wood Protection Association (AWPA) currently describes regional decay hazards in ground contact for North America and is based on condition assessments of utility poles from the 1970’s. Current work at the USDA Forest Service, Forest Products Laboratory is underway to analyze soil and wood samples from several National...

A Complete Multimode Equivalent-Circuit Theory for Electrical Design

PubMed Central

Williams, Dylan F.; Hayden, Leonard A.; Marks, Roger B.

1997-01-01

This work presents a complete equivalent-circuit theory for lossy multimode transmission lines. Its voltages and currents are based on general linear combinations of standard normalized modal voltages and currents. The theory includes new expressions for transmission line impedance matrices, symmetry and lossless conditions, source representations, and the thermal noise of passive multiports. PMID:27805153

Thermodynamic performance analysis of ramjet engine at wide working conditions

NASA Astrophysics Data System (ADS)

Ou, Min; Yan, Li; Tang, Jing-feng; Huang, Wei; Chen, Xiao-qian

2017-03-01

Although ramjet has the advantages of high-speed flying and higher specific impulse, the performance parameters will decline seriously with the increase of flight Mach number and flight height. Therefore, the investigation on the thermodynamic performance of ramjet is very crucial for broadening the working range. In the current study, a typical ramjet model has been employed to investigate the performance characteristics at wide working conditions. First of all, the compression characteristic analysis is carried out based on the Brayton cycle. The obtained results show that the specific cross-section area (A2 and A5) and the air-fuel ratio (f) have a great influence on the ramjet performance indexes. Secondly, the thermodynamic calculation process of ramjet is given from the view of the pneumatic thermal analysis. Then, the variable trends of the ramjet performance indexes with the flow conditions, the air-fuel ratio (f), the specific cross-sectional area (A2 and A5) under the fixed operating condition, equipotential dynamic pressure condition and variable dynamic pressure condition have been discussed. Finally, the optimum value of the specific cross-sectional area (A5) and the air-fuel ratio (f) of the ramjet model at a fixed work condition (Ma=3.5, H=12 km) are obtained.

Space Station Freedom pressurized element interior design process

NASA Technical Reports Server (NTRS)

Hopson, George D.; Aaron, John; Grant, Richard L.

1990-01-01

The process used to develop the on-orbit working and living environment of the Space Station Freedom has some very unique constraints and conditions to satisfy. The goal is to provide maximum efficiency and utilization of the available space, in on-orbit, zero G conditions that establishes a comfortable, productive, and safe working environment for the crew. The Space Station Freedom on-orbit living and working space can be divided into support for three major functions: (1) operations, maintenance, and management of the station; (2) conduct of experiments, both directly in the laboratories and remotely for experiments outside the pressurized environment; and (3) crew related functions for food preparation, housekeeping, storage, personal hygiene, health maintenance, zero G environment conditioning, and individual privacy, and rest. The process used to implement these functions, the major requirements driving the design, unique considerations and constraints that influence the design, and summaries of the analysis performed to establish the current configurations are described. Sketches and pictures showing the layout and internal arrangement of the Nodes, U.S. Laboratory and Habitation modules identify the current design relationships of the common and unique station housekeeping subsystems. The crew facilities, work stations, food preparation and eating areas (galley and wardroom), and exercise/health maintenance configurations, waste management and personal hygiene area configuration are shown. U.S. Laboratory experiment facilities and maintenance work areas planned to support the wide variety and mixtures of life science and materials processing payloads are described.

The impact of welfare reform on parents' ability to care for their children's health.

PubMed Central

Heymann, S J; Earle, A

1999-01-01

OBJECTIVES: Most of the national policy debate regarding welfare assumed that if middle-income mothers could balance work while caring for their children's health and development, mothers leaving welfare for work should be able to do so as well. Yet, previous research has not examined the conditions faced by mothers leaving welfare for work. METHODS: Using data from the National Longitudinal Survey of Youth, this study examined the availability of benefits that working parents commonly use to meet the health and developmental needs of their children; paid sick leave, vacation leave, and flexible hours. RESULTS: In comparison with mothers who had never received welfare, mothers who had been on Aid to Families with Dependent Children were more likely to be caring for at least 1 child with a chronic condition (37% vs 21%, respectively). Yet, they were more likely to lack sick leave for the entire time they worked (36% vs 20%) and less likely to receive other paid leave or flexibility. CONCLUSIONS: If current welfare recipients face similar conditions when they return to work, many will face working conditions that make it difficult or impossible to succeed in the labor force at the same time as meeting their children's health and developmental needs. PMID:10191791

Do Conditional Cash Transfers for Schooling Generate Lasting Benefits? A Five-Year Followup of PROGRESA/Oportunidades

ERIC Educational Resources Information Center

Behrman, Jere R.; Parker, Susan W.; Todd, Petra E.

2011-01-01

Conditional cash transfer (CCT) programs link public transfers to human capital investment in hopes of alleviating current poverty and reducing its intergenerational transmission. However, little is known about their long-term impacts. This paper evaluates longer-run impacts on schooling and work of the best-known CCT program, Mexico's…

[Study on empowerment factors for career continuity of hospital nurses].

PubMed

Kato, Hirosato; Ito, Yukie; Yoshida, Aki; Mizuno, Shizue; Ogoshi, Kumiko; Imamura, Tomoaki

2015-01-01

The resignation rate of nurses working in hospitals is extremely high. This study aims to identify both the factors related to the resignation of nurses and the empowerment factors supporting their job retention. In 2011 we conducted a Web-based questionnaire survey of nurses with less than 10 years of working experience. There were 25 survey items including the following reasons for choosing the current employment position, intention of continuing work, sense of fulfillment and the presence or absence of problems in the current workplace. In addition, nurses who previously had resigned were asked why they left their last workplace. The reasons why they chose the current workplace were markedly different between the not-resigned (A group) and previously resigned (B group) nurses. As a result of cluster analysis, the reasons for resignation were classified into six clusters; "overwork", "burnout", "bad atmosphere", "work life balance factors", "working conditions" and "marriage". In this study, it is shown that there is a positive correlation between the sense of fulfillment at work and the intention to do research work. It is suggested that encouragement of nurses to undertake research work is one of the empowerment factors supporting their job retention.

Association of active and passive smoking with occupational injury in manual workers: a cross-sectional study of the 2011 Korean working conditions survey.

PubMed

Kim, Hwan-Cheol; Lamichhane, Dirga Kumar; Jung, Dal-Young; Kim, Hyoung-Ryoul; Choi, Eun-Hee; Oh, Sung-Soo; Kang, Hee-Tae; Rhee, Kyung-Yong; Chang, Sei-Jin

2015-01-01

This study was conducted to investigate the relationship of active and passive smoking with occupational injury among manual workers. Data from the 2011 Korean Working Conditions Survey were analyzed for 12,507 manual workers aged ≥15 yr. Overall, 60.4% of men and 5.8% of women were current smokers. The prevalence of injury was higher among never smokers who were exposed to secondhand smoke (SHS) (7.7% in men and 8.1% in women) than current smokers (4.2% in men and 4.1% in women). After controlling for potential confounders, in men, compared to those who never smoked and were not exposed to SHS, people who never smoked and were exposed to SHS (adjusted odds ratio (aOR)=3.7, 2.2-6.4) and current smokers (aOR=2.5, 1.6-3.8) were more likely to experience injury. Among women, the aORs of occupational injury were 8.4 (4.2-16.7) for never smoking women with occasional exposure to SHS and 3.5 (95% CI: 1.4-8.7) for current smokers, in comparison to never smoking women who were never exposed to SHS at work (reference group). The present study suggests that exposure to SHS is a possible risk factor of occupational injury for never smoking men and women.

Adjunct Experiences with and Perceptions of Professional Development at a Texas Community College

ERIC Educational Resources Information Center

Miles, R. Mark

2017-01-01

Universities and colleges have developed an over-reliance on adjunct faculty, and as a result, researchers have begun to study adjunct faculty satisfaction as it relates to their working conditions. Current research indicates that professional development is a source that can contribute to satisfaction at work (Hoyt, 2012). However, the research…

A Great Place to Work: Improving Conditions for Staff in Young Children's Programs.

ERIC Educational Resources Information Center

Jorde-Bloom, Paula

This book discusses important issues of the day care profession. Topics include evaluation of the work place and the improvement of the day care environment for the benefit of staff, parents, and children. Organizational climate is considered in terms of the different types of early childhood programs and their relationship to current knowledge…

A follow-up study on the association of working conditions and lifestyles with the development of (perceived) mental symptoms in workers of a telecommunication enterprise.

PubMed

Suwazono, Y; Okubo, Y; Kobayashi, E; Kido, T; Nogawa, K

2003-10-01

This study investigated the association of working conditions and lifestyle with mental health in Japanese workers. A follow-up study was carried out in the Kanto district of Japan of workers in a telecommunications enterprise who received their first annual health check-up between 1992 and 1996 and were between 20 and 54 years old. Workers who reported mental symptoms, had a past history of disease, or current illness at their first check-up were excluded from the analysis. In total, the study included 23 837 workers. The association between working conditions and lifestyle and the development of mental symptoms was investigated by pooled logistic regression analyses. Working long hours and part-time work, as opposed to normal daytime hours of work, were factors associated with the development of mental symptoms in males, as were smoking, short sleeping hours, little physical exercise, rarely taking three meals a day, frequently eating within 1 h before sleep, much preference for salty meals and little preference for vegetables. Consumption of alcohol was negatively associated with the development of mental symptoms in males. Overall, the results suggested that the lower the Healthy Work and Lifestyle Score, the higher the risk of developing mental symptoms. Working conditions and lifestyle, especially food preferences, have an apparent influence on the mental health of Japanese workers. Moreover, the Healthy Work and Lifestyle Score indicates that working conditions and lifestyle appear to have a cumulative influence upon the mental health of Japanese workers.

The configuration of job placement for people with disabilities in the current economic contingencies in Italy: Social and clinical implications for health.

PubMed

Iudici, Antonio; Renzi, Cosimo

2015-10-01

In current socioeconomic conditions, working occupies a key role in people's lives, from both practical and existential perspectives. The absence of work can produce a considerable impact on the identity of individuals and entire communities. This emphasis on work is even more important for some groups in society, particularly for people with disabilities. In the Italian context, despite the existence of legislation on the subject, only 16% of people with disabilities have a job. This study was conducted to understand how people with disabilities become included in companies. This research proposes to highlight the ways in which corporate bodies' roles relate to people with disabilities' work in order to assess related theories, beliefs and critical aspects. Using the M.A.D.I.T. (Methodology of Textual Analysis of Computerized Data), some companies' placement managers for people with disabilities were interviewed. This analysis highlights conditions explaining current difficulties, especially in the absence of agreed upon criteria and a delegation. This research highlights the need to carry out a structural reorganization for the relationship between companies and employment agencies to avoid the risk that the lack of communication between the involved parties and the lack of support in the employment process may force companies to consider people with disabilities as an obstacle rather than a resource. Copyright © 2015 Elsevier Inc. All rights reserved.

[Staying and working at home or considering migrating: Survey-based study of African ophthalmologists].

PubMed

Nentwich, M M; Klauss, V; Wilhelm, F

2015-05-01

The shortage of ophthalmologists is a major obstacle in the struggle of fighting preventable blindness in sub-Saharan Africa. However, to date reasons affecting migration of ophthalmologists have not been completely understood. Evaluation of reasons reported by ophthalmologists for staying in their current work setting/country, of potential reasons for migration as well as of effects of German-African partnerships. In the years 2009-2011 and 2013 participants of continuous medical education courses in Ethiopia, Cameroon and Kenya were interviewed using a standardized questionnaire. A total of 106 ophthalmologists participated in this survey. In the years 2009/2010 participants were mainly board certified ophthalmologists, while the 2011/2013 surveys were answered mainly by residents. The main reasons for staying in their current region/country were good working conditions, commitment to help/patriotism, possibility of further training, good income and familial ties. Professional development elsewhere and better income abroad were named as the main reasons for considering migration followed by better technical equipment elsewhere and insecurity in the home country. Good working conditions and the possibility of further training were named as the top reasons for staying in the current region/country apart from commitment to help and familial ties. Therefore, international cooperation programs aiming at improving training of ophthalmologists and establishing an ophthalmic infrastructure may have a role in promoting ophthalmic care in Africa.

Level of functioning, perceived work ability, and work status among psychiatric patients with major mental disorders.

PubMed

Karpov, B; Joffe, G; Aaltonen, K; Suvisaari, J; Baryshnikov, I; Näätänen, P; Koivisto, M; Melartin, T; Oksanen, J; Suominen, K; Heikkinen, M; Isometsä, E

2017-07-01

Major mental disorders are highly disabling conditions that result in substantial socioeconomic burden. Subjective and objective measures of functioning or ability to work, their concordance, or risk factors for them may differ between disorders. Self-reported level of functioning, perceived work ability, and current work status were evaluated among psychiatric care patients with schizophrenia or schizoaffective disorder (SSA, n=113), bipolar disorder (BD, n=99), or depressive disorder (DD, n=188) within the Helsinki University Psychiatric Consortium Study. Correlates of functional impairment, subjective work disability, and occupational status were investigated using regression analysis. DD patients reported the highest and SSA patients the lowest perceived functional impairment. Depressive symptoms in all diagnostic groups and anxiety in SSA and BD groups were significantly associated with disability. Only 5.3% of SSA patients versus 29.3% or 33.0% of BD or DD patients, respectively, were currently working. About half of all patients reported subjective work disability. Objective work status and perceived disability correlated strongly among BD and DD patients, but not among SSA patients. Work status was associated with number of hospitalizations, and perceived work disability with current depressive symptoms. Psychiatric care patients commonly end up outside the labour force. However, while among patients with mood disorders objective and subjective indicators of ability to work are largely concordant, among those with schizophrenia or schizoaffective disorder they are commonly contradictory. Among all groups, perceived functional impairment and work disability are coloured by current depressive symptoms, but objective work status reflects illness course, particularly preceding psychiatric hospitalizations. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

‘Killing Me Softly With His/Her Song’: How Leaders Dismantle Followers’ Sense of Work Meaningfulness

PubMed Central

Kipfelsberger, Petra; Kark, Ronit

2018-01-01

Leaders influence followers’ meaning and play a key role in shaping their employees’ experience of work meaningfulness. While the dominant perspective in theory and in empirical work focuses on the positive influence of leaders on followers’ work meaningfulness, our conceptual model explores conditions in which leaders may harm followers’ sense of meaning. We introduce six types of conditions: leaders’ personality traits, leaders’ behaviors, the relationship between leader and follower, followers’ attributions, followers’ characteristics, and job design under which leaders’ meaning making efforts might harm or ‘kill’ followers’ sense of work meaningfulness. Accordingly, we explore how these conditions may interact with leaders’ meaning making efforts to lower levels of followers’ sense of meaning, and in turn, lead to negative personal outcomes (cynicism, lower well-being, and disengagement), as well as negative organizational outcomes (corrosive organizational energy, higher turnover rates, and lower organizational productivity). By doing so, our research extends the current literature, enabling a more comprehensive understanding of leaders’ influence on followers’ work meaningfulness, while considering the dark side of meaning making. PMID:29867638

[Effort-reward imbalance at work and depression: current research evidence].

PubMed

Siegrist, J

2013-01-01

In view of highly prevalent stressful conditions in modern working life, in particular increasing work pressure and job insecurity, it is of interest to know whether specific constellations of an adverse psychosocial work environment increase the risk of depressive disorder among employed people. This contribution gives a short overview of current research evidence based on an internationally established work stress model of effort-reward imbalance. Taken together, results from seven prospective epidemiological investigations demonstrate a two-fold elevated relative risk of incident depressive disorder over a mean observation period of 2.7 years among exposed versus non-exposed employees. Additional findings from experimental and quasi-experimental studies point to robust associations of effort-reward imbalance at work with proinflammatory cytokines and markers of reduced immune competence. These latter markers may indicate potential psychobiological pathways. In conclusion, incorporating this new knowledge into medical treatment and preventive efforts seems well justified.

Prevalence of Depressive Symptoms and Related Factors in Korean Employees: The Third Korean Working Conditions Survey (2011).

PubMed

Park, Ji Nam; Han, Mi Ah; Park, Jong; Ryu, So Yeon

2016-04-14

The aim of this study was to analyze the association between general working conditions and depressive symptoms among Korean employees. The target population of the study was native employees nationwide who were at least 15 years old, and 50,032 such individuals were enrolled in the study. Depressive symptoms was assessed using the WHO-5 wellbeing index. Associations between general characteristics, job-related characteristics, work environment, and depressive symptoms were tested using chi-square tests, t-tests, and multiple logistic regression analysis. The prevalence of depressive symptoms was 39% (40.7% in males and 36.5% in females). Multiple regression analysis revealed that male subjects, older subjects, subjects with higher education status, subjects with lower monthly income, current smokers, and frequent drinkers were more likely to have depressive symptoms. In addition, longer weekly work hours, occupation type (skilled, unskilled, operative, or economic sector), shift work, working to tight deadlines, exposure to stress at work, and hazard exposure were associated with depressive symptoms. This representative study will be a guide to help manage depression among Korean employees. We expect that further research will identify additional causal relationships between general or specific working conditions and depression.

Optimization of Experimental Conditions of the Pulsed Current GTAW Parameters for Mechanical Properties of SDSS UNS S32760 Welds Based on the Taguchi Design Method

NASA Astrophysics Data System (ADS)

Yousefieh, M.; Shamanian, M.; Saatchi, A.

2012-09-01

Taguchi design method with L9 orthogonal array was implemented to optimize the pulsed current gas tungsten arc welding parameters for the hardness and the toughness of super duplex stainless steel (SDSS, UNS S32760) welds. In this regard, the hardness and the toughness were considered as performance characteristics. Pulse current, background current, % on time, and pulse frequency were chosen as main parameters. Each parameter was varied at three different levels. As a result of pooled analysis of variance, the pulse current is found to be the most significant factor for both the hardness and the toughness of SDSS welds by percentage contribution of 71.81 for hardness and 78.18 for toughness. The % on time (21.99%) and the background current (17.81%) had also the next most significant effect on the hardness and the toughness, respectively. The optimum conditions within the selected parameter values for hardness were found as the first level of pulse current (100 A), third level of background current (70 A), first level of % on time (40%), and first level of pulse frequency (1 Hz), while they were found as the second level of pulse current (120 A), second level of background current (60 A), second level of % on time (60%), and third level of pulse frequency (5 Hz) for toughness. The Taguchi method was found to be a promising tool to obtain the optimum conditions for such studies. Finally, in order to verify experimental results, confirmation tests were carried out at optimum working conditions. Under these conditions, there were good agreements between the predicted and the experimental results for the both hardness and toughness.

[Risk of certain obstetric pathologies in women employed in working conditions non-complying with the current legal status on work load and working conditions appropriate for pregnant women].

PubMed

Makowiec-Dabrowska, Teresa; Hanke, Wojciech; Sobala, Wojciech; Radwan-Włodarczyk, Zyta; Koszada-Włodarczyk, Wiesława

2003-01-01

The aim of the study was to define the incidence of prematurity and small-for-gestational age (SGA) infants in occupationally involved pregnant women, and to find out how far working conditions departing from binding regulations contribute to the risk of the development of these pathologies. The study was carried out on a representative sample of 3050 women employed for longer than one week during pregnancy in the Łódź district. An interview conducted with the subjects few days after delivery was the source of information about working conditions. The obtained information was compared with the real situation in about 10% of randomly selected workposts. A high level of consistence was observed. The study revealed that almost 60% of women work in conditions, which do not comply with the Labor Code provisions setting working conditions permissible for pregnant women. In the study group, 4.68% of prematurity and 6.15% of SGA were recorded. A 66% excess in the risk of delivering SGA infants in case of at least one factor not complying with regulations was revealed. The excess was growing with the increased number of departures from regulations and continuation of employment during pregnancy. It was estimated that the number of SGA cases would decrease by 28% if the working conditions would have met the requirements. A prolonged time of work, local vibration for > 4h/shift, forced work pace, excessive effort and forced body position during the work performance contributed mostly to the risk of pathology. Interestingly, the risk of premature delivery was lower by about 40% in women working in unsatisfactory conditions, which is attributed to termination of work immediately after the occurrence of pregnancy-threatening symptoms. Only those women whose pregnancy was not threatened with pathology could continue their work. The study revealed a quite large number of workplaces not complying with regulations on working conditions permissible for pregnant women. Therefore, studies in this area should be continued by physicians attending pregnant women, under programs aimed at preventing prematurity, and they should be expanded to include the detection of SGA during gestation and the implementation of relevant prophylactics.

The effect of resting blood flow occlusion on exercise tolerance and W'.

PubMed

Broxterman, Ryan M; Craig, Jesse C; Ade, Carl J; Wilcox, Samuel L; Barstow, Thomas J

2015-09-15

It has previously been postulated that the anaerobic work capacity (W') may be utilized during resting blood flow occlusion in the absence of mechanical work. We tested the hypothesis that W' would not be utilized during an initial range of time following the onset of resting blood flow occlusion, after which W' would be utilized progressively more. Seven men completed blood flow occlusion constant power severe intensity handgrip exercise to task failure following 0, 300, 600, 900, and 1,200 s of resting blood flow occlusion. The work performed above critical power (CP) was not significantly different between the 0-, 300-, and 600-s conditions and was not significantly different from the total W' available. Significantly less work was performed above CP during the 1,200-s condition than the 900-s condition (P < 0.05), while both conditions were significantly less than the 0-, 300-, and 600-s conditions (P < 0.05). The work performed above CP during these conditions was significantly less than the total W' available (P < 0.05). The utilization of W' during resting blood flow occlusion did not begin until 751 ± 118 s, after which time W' was progressively utilized. The current findings demonstrate that W' is not utilized during the initial ∼751 s of resting blood flow occlusion, but is progressively utilized thereafter, despite no mechanical work being performed. Thus, the utilization of W' is not exclusive to exercise, and a constant amount of work that can be performed above CP is not the determining mechanism of W'. Copyright © 2015 the American Physiological Society.

Mindblindness: metaphor and neuroaesthetics in the works of Silas Weir Mitchell and Simon Baron-Cohen.

PubMed

Swenson, Kristine

2013-01-01

Silas Weir Mitchell's novel, When All the Woods are Green (1894), acknowledges the medical use of mindblindness (agnosia) but also casts it as a developmental disorder, bringing it provocatively close to how current neuropsychologist, Simon Baron-Cohen and his followers use the term in relation to autism. This chapter traces the mindblindess metaphor in the works of Mitchell and Baron-Cohen to show how mindblindness informs the larger paradigms by which they theorize the brain. This analysis suggests that Baron-Cohen, and thus much current thinking about autism spectrum conditions, is influenced by Victorian-era cultural assumptions and neurosexism, a connection that calls for scrutiny of Baron-Cohen's current models of the brain and theories of autism. This chapter also demonstrates the extent to which Mitchell used fiction and advocated writing as neuroaesthetic tools and thus bridged in his work cognitive science and aesthetics--a connection that current scholars of neuroaesthetics are now theorizing. © 2013 Elsevier B.V. All rights reserved.

Profile of Women Collegiate Strength and Conditioning Coaches.

PubMed

Laskowski, Karisa D; Ebben, William P

2016-12-01

Laskowski, KD and Ebben, WP. Profile of women collegiate strength and conditioning coaches. J Strength Cond Res 30(12): 3481-3493, 2016-This study describes the careers of women collegiate strength and conditioning coaches, including specifics of the universities and athletic departments they work for, responsibilities and demands of their jobs, compensation and benefits, preparation and qualifications, likes and dislikes about their work, and the role that gender plays in their work. Forty-three coaches participated for a response rate of 29.1% (43 of 148). The survey was divided into 5 sections, including university profile, position profile, personal profile, job satisfaction, and comments. Results show that women occupy approximately 32% of all strength and conditioning positions. Those who are full-time coaches work approximately 55.6 hours per week, starting their workday at 6:02 AM and ending at 5:40 PM, on average. Part-time coaches worked 42.5 hours per week. Those who were in director positions earned approximately $76,000 per year, whereas full-time assistants averaged approximately $39,300 per year. Most coaches had master's degree and held the CSCS and USAW certifications. These coaches averaged 7.14 years of full-time experience. Coaches identified a variety of advantages and disadvantages associated with their work and described the influence of gender in their work. These results provide normative data about employment conditions of women strength and conditioning coaches and those who are considering this career. These data also document the current state of affairs in the profession and can be used in comparison with the past benchmarks in an attempt to understand the role of women in the collegiate strength and conditioning profession.

Modern Interactive Technologies of Professional Self-Determination under the Conditions of Overcoming Conflicting Realities

ERIC Educational Resources Information Center

Hasanova, Irina I.; Kotova, Svetlana S.; Kandrashina, Elena A.

2016-01-01

The urgency of the problem under study is due to the fact that the professional life of a person under current conditions is highly dynamic; moreover, the attitude to the profession, the meaning of work, and its results is changing. The purpose of this article is to develop innovative psychological and pedagogical support of the professional…

Forest conditions and trends in the northern United States

Treesearch

Stephen R. Shifley; Francisco X. Aguilar; Nianfu Song; Susan I. Stewart; David J. Nowak; Dale D. Gormanson; W. Keith Moser; Sherri Wormstead; Eric J. Greenfield

2012-01-01

This section describes current conditions and trends for the 20 Northern States by focusing on selected characteristics associated with forest sustainability. Its format is based upon a set of 64 indicators within 7 broad criteria that the United States and 11 other countries have adopted under the auspices of the Montréal Process Working Group on Criteria and...

The Role of Cognitive Load in Intentional Forgetting Using the Think/No-Think Task.

PubMed

Noreen, Saima; de Fockert, Jan W

2017-01-01

We investigated the role of cognitive control in intentional forgetting by manipulating working memory load during the think/no-think task. In two experiments, participants learned a series of cue-target word pairs and were asked to recall the target words associated with some cues or to avoid thinking about the target associated with other cues. In addition to this, participants also performed a modified version of the n-back task which required them to respond to the identity of a single target letter present in the currently presented cue word (n = 0 condition, low working memory load), and in either the previous cue word (n = 1 condition, high working memory load, Experiment 1) or the cue word presented two trials previously (n = 2 condition, high working memory load, Experiment 2). Participants' memory for the target words was subsequently tested using same and novel independent probes. In both experiments it was found that although participants were successful at forgetting on both the same and independent-probe tests in the low working memory load condition, they were only successful at forgetting on the same-probe test in the high working memory load condition. We argue that our findings suggest that the high load working memory task diverted attention from direct suppression and acted as an interference-based strategy. Thus, when cognitive resources are limited participants can switch between the strategies they use to prevent unwanted memories from coming to mind.

Job Satisfaction Analysis in Rural China: A Qualitative Study of Doctors in a Township Hospital

PubMed Central

Chen, Qiwei; Yang, Lan; Tighe, Scott S.

2017-01-01

Background. Township hospitals in China provide rural communities with basic but much needed critical health care services. The doctors working in these hospitals often feel unsatisfied when considering their work schedules and financial rewards. Method. To explore job satisfaction of health workers in a township hospital, a qualitative study was conducted of 39 doctors from five township hospitals in Guangxi Zhuang Autonomous Region. The goal was to understand the level of job satisfaction of doctors and to make recommendations for improvements. Results. About 75% (28/39) of the doctors expressed negative attitudes related to their work conditions. Slightly more than half (22/39) mentioned they should receive greater compensation for their work and more than one were seriously considering other options. Many participants (35/39) showed their satisfaction about the achievement of serving as a doctor. Conclusion. Their main concerns related to job satisfaction included working conditions, financial rewards, and the doctor's relationships with patients. Increasing the incomes and fringe benefits of healthcare workers, improving their work conditions, and providing training and continuing education opportunities would help rural clinics retain doctors and eliminate the current unsatisfactory conditions. The findings also highlight the need for the government to increase financial support of township hospitals. PMID:28409052

Working Memory and Mental Arithmetic: A Case for Dual Central Executive Resources

ERIC Educational Resources Information Center

Ketelsen, Kirk; Welsh, Marilyn

2010-01-01

The current study was designed to examine the possible existence of two limited-capacity pools of central executive resources: one each for verbal and visuospatial processing. Ninety-one college students (M age = 19.0, SD = 2.2) were administered a verbal working memory task that involved updating numbers in 2-, 3-, and 4-load conditions. The task…

Optimal management of non-Markovian biological populations

USGS Publications Warehouse

Williams, B.K.

2007-01-01

Wildlife populations typically are described by Markovian models, with population dynamics influenced at each point in time by current but not previous population levels. Considerable work has been done on identifying optimal management strategies under the Markovian assumption. In this paper we generalize this work to non-Markovian systems, for which population responses to management are influenced by lagged as well as current status and/or controls. We use the maximum principle of optimal control theory to derive conditions for the optimal management such a system, and illustrate the effects of lags on the structure of optimal habitat strategies for a predator-prey system.

[Distress among physicians in hospitals - an investigation in Baden-Württemberg, Germany].

PubMed

Bauer, J; Groneberg, D A

2013-11-01

Current working conditions of physicians in hospitals display characteristics, which on the long term are harmful for the physicians mental and physical health (distress). There are problems concerning the work flow and the organization of working time which finally leads to gratification crises. How physicians perceive their stress-related working conditions is the issue this study wants to investigate. In this study 12 062 physicians in hospitals were invited to an anonymized online-survey. 2064 physicians took part. The basis of this investigation is built by 2 theoretical stress models: The effort-reward-imbalance models of Siegrist and the job-demand-control model of Karasek. Through these theoretical models distress is measured. The study revealed a high prevalence (55,5 %) of distress among physicians in hospitals. Furthermore there were significant differences between gender (59,7 % of female and 51,5 % of male physicians; OR 1,40; 95 %-CI 1,17‑1,66; p < 0,001), between age (61,9 % of under 35-year-old and 49,4 % of over 59-year-old; OR 1,67; 95 %-CI 1,06-2,62; p < 0,001) and between the functional position (24,6 % of chief physician and 63,8 % of junior doctors; OR 5,40; 95 %-CI 3,03-9,65; p < 0,001). An additional analysis of the psychosocial aspects of the working conditions showed that these aspects are rated positively by this sample. These results have to be considered as a cause for concern, because this high prevalence of distress will lead sooner or later to a migration of qualified physicians abroad or to other (less stressful) jobs. In order to prevent a future shortage of qualified physicians, the working conditions have to be adapted to current needs and expectations of the younger generation. © Georg Thieme Verlag KG Stuttgart · New York.

Working Conditions of the Nursing Workforce Excerpts from a Policy Roundtable at AcademyHealth's 2003 Annual Research Meeting

PubMed Central

Hope, Hollis A

2004-01-01

The role of nursing in the delivery of health care has emerged as a complex and cross-cutting issue ripe for inquiry and multidisciplinary research. Indeed, problems in the nursing workforce have risen high on the agendas on many influential organizations, including the American Academy of Nursing, the Institute of Medicine, the National Quality Forum, The Robert Wood Johnson Foundation, and others. In an effort to clarify current research issues and advance an agenda for future investigations, Dr. Peter Buerhaus at Vanderbilt University organized a round table focused on the working conditions of the nursing workforce at the AcademyHealth 2003 Annual Research Meeting in Nashville, Tenn. Chaired by the University of California, Los Angeles, School of Public Health's Jack Needleman, the “Working Conditions of the Nursing Workforce” roundtable proved to be a provocative exchange of views among researchers and users of research. Participants shared background about their role in advancing the research, identified gaps in current research, and suggested specific areas for further research. What follows is an edited transcript of the Roundtable that, in addition to Dr. Needleman, included Ellen Kurtzman, National Quality Forum; Barbara Mark, University of North Carolina, Chapel Hill; Lori Melichar, The Robert Wood Johnson Foundation; and Donald Steinwachs, Johns Hopkins University. PMID:15149473

Trout Creek, Oregon Watershed Assessment; Findings, Condition Evaluation and Action Opportunities, 2002 Technical Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Runyon, John

The purpose of the assessment is to characterize historical and current watershed conditions in the Trout Creek Watershed. Information from the assessment is used to evaluate opportunities for improvements in watershed conditions, with particular reference to improvements in the aquatic environment. Existing information was used, to the extent practicable, to complete this work. The assessment will aid the Trout Creek Watershed Council in identifying opportunities and priorities for watershed restoration projects.

Psychosocial working conditions and diabetes self-management at work: A qualitative study.

PubMed

Loerbroks, Adrian; Nguyen, Xuan Quynh; Vu-Eickmann, Patricia; Krichbaum, Michael; Kulzer, Bernhard; Icks, Andrea; Angerer, Peter

2018-06-01

We conducted a qualitative study to expand our current understanding of the potential link between psychosocial working conditions and diabetes self-management at work. Thirty employed adults with diabetes mellitus living in Germany (n = 19 with type 1, n = 11 with type 2, 57% female, aged 24-64 years) were recruited. Using a topic guide, we carried out in-depth interviews in face-to-face contact or by telephone. Interviews were transcribed and content-analyzed using MaxQDA. Psychosocial working conditions perceived to detrimentally affect self-management activities included, amongst others, a high workload, poor job control, unhygienic working environments, the requirement to work under high or fluctuating temperature, perceived social norms at the workplace, and the attitude to prioritize work-related demands as opposed to diabetes-related demands. The types of self-management activities considered to be adversely affected related to glucose monitoring, insulin injections, dietary control, the ability to recognize hypoglycemia and health care use. Various types of occupational psychosocial factors may determine diabetes self-management practices at the workplace. Quantitative studies are needed to confirm our observations. Subsequently, interventions could be developed and evaluated to improve opportunities to adequately engage into diabetes self-management at work. Copyright © 2018 Elsevier B.V. All rights reserved.

Associations of psychosocial working conditions with health outcomes, quality of care and intentions to leave the profession: results from a cross-sectional study among physician assistants in Germany.

PubMed

Vu-Eickmann, Patricia; Li, Jian; Müller, Andreas; Angerer, Peter; Loerbroks, Adrian

2018-04-24

Numerous epidemiological studies among health care staff have documented associations of adverse psychosocial working conditions with poorer health-related outcomes, a reduced quality of patient care and intentions to leave the profession. The evidence for physician assistants in Germany remains limited though. We surveyed a total of 994 physician assistants between September 2016 and April 2017. Psychosocial working conditions were measured by the established effort-reward imbalance (ERI) questionnaire and by a questionnaire specifically developed to capture psychosocial working conditions among physicians. Health outcomes (i.e., self-rated health, depression, anxiety), self-rated quality of care and the intention to leave the profession were assessed by established measures. We ran multivariable logistic regression analyses. The prevalence of work stress in terms of ERI equalled 73.77%. Work stress according to the ERI model was associated with significantly poorer self-rated health [odds ratio (OR) 3.62], elevated symptoms of depression (OR 8.83) and anxiety (OR 4.95), poorer quality of care (OR for medical errors 4.04; OR for interference of work with patient care 3.88) and an increased intention to leave one's current profession (OR 3.74). The PA-specific questionnaire showed similar, albeit weaker, associations (all ORs > 1.22). Our results are in line with previous findings among health care staff and provide specific and novel evidence for physician assistants. Interventions aiming at the improvement of working conditions seem needed given their potential adverse consequences in terms of employee health, quality of care, and personnel policy.

The Work-It Study for people with arthritis: Study protocol and baseline sample characteristics.

PubMed

Keysor, Julie J; AlHeresh, Rawan; Vaughan, Molly; LaValley, Michael P; Allaire, Saralynn

2016-06-14

People with arthritis are at risk of work disability. Job accommodation and educational programs delivered before imminent work loss can minimize work disability, yet are not currently being widely implemented. The Work-It Study is a randomized controlled trial testing the efficacy of a problem solving program delivered by physical and occupational therapy practitioners to prevent work loss over a two-year period among people with arthritis and rheumatological conditions. The purpose of this paper is to describe the protocol of the randomized controlled trial, and describe the baseline characteristics of the subjects and their work outcomes. 287 participants were recruited from the Boston area in Massachusetts, USA. Eligible participants were aged between 21-65, self-reported a physicians' diagnosis of arthritis, rheumatic condition, or chronic back pain, reported a concern about working now or in the near future due to your health, worked at least 15 hours a week, had plans to continue working, and worked or lived in Massachusetts. Subjects were recruited through community sources and rheumatology offices. Participants in the experimental group received a structured interview and an education and resource packet, while participants in the control received the resource packet only. The baseline characteristics and work related outcomes of the participants were analyzed. To our knowledge, the Work-It Study is the largest and most diverse randomized controlled trial to date aiming to identify and problem solve work-related barriers, promote advocacy, and foster work disability knowledge among people with chronic disabling musculoskeletal conditions. Despite advances in medical management of arthritis and other rheumatological and musculoskeletal conditions, many people still have concerns about their ability to remain employed and are seeking strategies to help them sustain employment.

Measurement system for determination of current-voltage characteristics of PV modules

NASA Astrophysics Data System (ADS)

Idzkowski, Adam; Walendziuk, Wojciech; Borawski, Mateusz; Sawicki, Aleksander

2015-09-01

The realization of a laboratory stand for testing photovoltaic panels is presented here. The project of the laboratory stand was designed in SolidWorks software. The aim of the project was to control the electrical parameters of a PV panel. For this purpose a meter that measures electrical parameters i.e. voltage, current and power, was realized. The meter was created with the use of LabJack DAQ device and LabVIEW software. The presented results of measurements were obtained in different conditions (variable distance from the source of light, variable tilt angle of the panel). Current voltage characteristics of photovoltaic panel were created and all parameters could be detected in different conditions. The standard uncertainties of sample voltage, current, power measurements were calculated. The paper also gives basic information about power characteristics and efficiency of a solar cell.

Demographic, migration status, and work-related changes in Asian female sex workers surveyed in Sydney, 1993 and 2003.

PubMed

Pell, C; Dabbhadatta, J; Harcourt, C; Tribe, K; O'Connor, C

2006-04-01

To compare demography, sexual health awareness, migration and workplace conditions of Asian female sex workers in Sydney in 1993 and 2003. A Chinese interpreter and a Thai-speaking health education officer (HEO) were used to administer a questionnaire survey to Thai- and Chinese-speaking sex workers attending sexual health clinics in 1993. A follow-up survey, which included some women contacted at work as well as clinic attenders, was administered by Thai- and Chinese-speaking HEOs in 2003. Ninety-one female sex workers were surveyed in 1993 and 165 in 2003. Median age increased (26 years vs. 33 years, p=0.000), as did numbers of Chinese- versus Thai-speakers (1993, 25.3% Chinese vs. 2003, 58.2% Chinese, p=0.000). In 2003, the women reported more years of schooling and better English skills. Fewer reported previous sex work (48.4% vs. 17.6%, p=0.000). Numbers currently or ever on a contract decreased sharply (27.5% vs. 9.1%, p=0.000) and the majority were apparently working legally. Condom use at work for vaginal (51.6% vs. 84.8%) and oral sex (39.6% vs. 66.1%) increased significantly (p=0.001). Chinese-speaking sex workers were less informed about HIV transmission and safer sex practices than were Thai sex workers. Drug and alcohol use was low. Positive changes have occurred in the conditions of Asian female sex workers surveyed over 10 years in Sydney. Maintaining current levels of health service delivery will ensure continued improvements in health and workplace conditions and address inequalities between language groups.

The research on thermal adaptability reinforcement technology for photovoltaic modules

NASA Astrophysics Data System (ADS)

Su, Nana; Zhou, Guozhong

2015-10-01

Nowadays, Photovoltaic module contains more high-performance components in smaller space. It is also demanded to work in severe temperature condition for special use, such as aerospace. As temperature rises, the failure rate will increase exponentially which makes reliability significantly reduce. In order to improve thermal adaptability of photovoltaic module, this paper makes a research on reinforcement technologies. Thermoelectric cooler is widely used in aerospace which has harsh working environment. So, theoretical formulas for computing refrigerating efficiency, refrigerating capacity and temperature difference are described in detail. The optimum operating current of three classical working condition is obtained which can be used to guide the design of driven circuit. Taken some equipment enclosure for example, we use thermoelectric cooler to reinforce its thermal adaptability. By building physical model and thermal model with the aid of physical dimension and constraint condition, the model is simulated by Flotherm. The temperature field cloud is shown to verify the effectiveness of reinforcement.

Effect of process parameters on metal transfer of hyperbaric GMAW of duplex stainless steels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Olsen, J.M.; Dos Santos, J.F.; Richardson, I.M.

1994-12-31

This work presents the preliminary results of a comprehensive and systematic evaluation of current rise and fall rates as well as shielding gas composition and their affect on the metal transfer, when duplex stainless steels are GMA welded under hyperbaric conditions using the short circuit metal transfer mode. The evaluation of the test results are based on an examination of the welding process signals recorded on a transient recorder. Over a time period of 500 ms, the signal was measured to assess the process instability, current rise and fall rates and their inter-relationship. The results presented in this study indicatemore » that for a given welding condition, the appropriate selection of current rise and fall rates can minimize the effect of instabilities caused by high ambient pressure. The presence of active gases in the shielding did not significantly affect the metal transfer behavior. All the experiments described in this work have been carried out in the hyperbaric test facilities of the GKSS-Forschungszentrum in Germany.« less

Current problems and working status of female anesthesiologists in Japan.

PubMed

Komori, Makiko; Nishiyama, Keiko; Ichikawa, Junko; Kodaka, Mitsuharu; Tomizawa, Yasuko

2014-05-01

The rapid growth of the elderly population and the progress in surgical techniques in Japan have led to increased numbers of patients who undergo surgery. Anesthetics are essential for surgery. A survey conducted by the Japanese Society of Anesthesiologists showed that, during the past 10 years, the proportion of females among all the members has increased from 27 to 35 %, and the proportion of female councilors has risen from 3.9 to 6.7 %. However, the conditions of full-time employment remain inadequate for female physicians. Therefore, many female physicians in their 30s or older do not work as anesthesiologists. To support female anesthesiologists and their vital roles in surgical diagnosis and treatment, return-to-work assistance programs have been developed. It is also necessary to improve the working conditions for female anesthesiologists to allow them to continue their work, and to provide education for young female physicians to enhance their professional pride.

Theory of step on leading edge of negative corona current pulse

NASA Astrophysics Data System (ADS)

Gupta, Deepak K.; Mahajan, Sangeeta; John, P. I.

2000-03-01

Theoretical models taking into account different feedback source terms (e.g., ion-impact electron emission, photo-electron emission, field emission, etc) have been proposed for the existence and explanation of the shape of negative corona current pulse, including the step on the leading edge. In the present work, a negative corona current pulse with the step on the leading edge is obtained in the presence of ion-impact electron emission feedback source only. The step on the leading edge is explained in terms of the plasma formation process and enhancement of the feedback source. Ionization wave-like movement toward the cathode is observed after the step. The conditions for the existence of current pulse, with and without the step on the leading edge, are also described. A qualitative comparison with earlier theoretical and experimental work is also included.

Paradigm Change: Alternate Approaches to Constitutive and Necking Models for Sheet Metal Forming

NASA Astrophysics Data System (ADS)

Stoughton, Thomas B.; Yoon, Jeong Whan

2011-08-01

This paper reviews recent work proposing paradigm changes for the currently popular approach to constitutive and failure modeling, focusing on the use of non-associated flow rules to enable greater flexibility to capture the anisotropic yield and flow behavior of metals using less complex functions than those needed under associated flow to achieve that same level of fidelity to experiment, and on the use of stress-based metrics to more reliably predict necking limits under complex conditions of non-linear forming. The paper discusses motivating factors and benefits in favor of both associated and non-associated flow models for metal forming, including experimental, theoretical, and practical aspects. This review is followed by a discussion of the topic of the forming limits, the limitations of strain analysis, the evidence in favor of stress analysis, the effects of curvature, bending/unbending cycles, triaxial stress conditions, and the motivation for the development of a new type of forming limit diagram based on the effective plastic strain or equivalent plastic work in combination with a directional parameter that accounts for the current stress condition.

Stress, health and satisfaction of Australian and German doctors--a comparative study.

PubMed

Mache, Stefanie; Vitzthum, Karin; Klapp, Burghard F; Groneberg, David A

2012-01-01

Currently no study exists focusing on international differences in perception of stress, working conditions and satisfaction of hospital staff. Therefore the present study aimed to examine and compare the work and privacy situation of Australian and German physicians. The present study was designed as a cross-sectional comparison using questionnaire data. The population consisted of representative samples of 310 German and 256 Australian hospital doctors who received mailed questionnaires. The questionnaires contained items on demography, perception of stress, working conditions, job satisfaction and Life satisfaction. According to the comparison, German physicians perceived higher values of work stress. They work significantly longer hours than Australian doctors. In general, work intensity and demands are highly rated in both countries. In terms of job and life satisfaction, Australian doctors responded more positively than German doctors. This is the first comparative study illustrating a subjective evaluation of physicians' perception of stress, their work and privacy situation in two different countries. Based on these results health policy decisions can be developed.

Quality of work life: experiences of Iranian nurses.

PubMed

Vagharseyyedin, Seyyed Abolfazl; Vanaki, Zohreh; Mohammadi, Eesa

2011-03-01

The purpose of this qualitative study was to describe the experiences of Iranian nurses concerning their quality of work life. A purposive sample of nurses (n = 14) was recruited from two university hospitals. The data were collected through unstructured interviews and were analyzed by using qualitative content analysis. The results indicated that the participants discerned their quality of work life by assessing how favorable were their working conditions, the level of fulfilment of their personal needs, and the impact of their working conditions on their private life and their social life. Three main themes were identified: quality of work life, as experienced from a personal perspective; quality of work life, as experienced from a sociocultural perspective; and quality of work life, as experienced from an organizational-professional perspective. The results of the present study will help Iranian nurse administrators to adopt effective strategies in order to improve nurses' quality of work life. Future research can broaden the scope of the current results and offer a more comprehensive understanding of nurses' quality of work life. © 2011 Blackwell Publishing Asia Pty Ltd.

Inflationary tensor fossils in large-scale structure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dimastrogiovanni, Emanuela; Fasiello, Matteo; Jeong, Donghui

Inflation models make specific predictions for a tensor-scalar-scalar three-point correlation, or bispectrum, between one gravitational-wave (tensor) mode and two density-perturbation (scalar) modes. This tensor-scalar-scalar correlation leads to a local power quadrupole, an apparent departure from statistical isotropy in our Universe, as well as characteristic four-point correlations in the current mass distribution in the Universe. So far, the predictions for these observables have been worked out only for single-clock models in which certain consistency conditions between the tensor-scalar-scalar correlation and tensor and scalar power spectra are satisfied. Here we review the requirements on inflation models for these consistency conditions to bemore » satisfied. We then consider several examples of inflation models, such as non-attractor and solid-inflation models, in which these conditions are put to the test. In solid inflation the simplest consistency conditions are already violated whilst in the non-attractor model we find that, contrary to the standard scenario, the tensor-scalar-scalar correlator probes directly relevant model-dependent information. We work out the predictions for observables in these models. For non-attractor inflation we find an apparent local quadrupolar departure from statistical isotropy in large-scale structure but that this power quadrupole decreases very rapidly at smaller scales. The consistency of the CMB quadrupole with statistical isotropy then constrains the distance scale that corresponds to the transition from the non-attractor to attractor phase of inflation to be larger than the currently observable horizon. Solid inflation predicts clustering fossils signatures in the current galaxy distribution that may be large enough to be detectable with forthcoming, and possibly even current, galaxy surveys.« less

Parallel, staged opening switch power conditioning techniques for flux compression generator applications

NASA Astrophysics Data System (ADS)

Reinovsky, R. E.; Levi, P. S.; Bueck, J. C.; Goforth, J. H.

The Air Force Weapons Laboratory, working jointly with Los Alamos National Laboratory, has conducted a series of experiments directed at exploring composite, or staged, switching techniques for use in opening switches in applications which require the conduction of very high currents (or current densities) with very low losses for relatively long times (several tens of microseconds), and the interruption of these currents in much shorter times (ultimately a few hundred nanoseconds). The results of those experiments are reported.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harrington, Timothy D.; Babauta, Jerome T.; Davenport, Emily K.

We investigated ion transport limitations on 3D graphite felt electrodes by growing Geobacter sulfurreducens biofilms with advection to eliminate external mass transfer limitations. We characterized ion transport limitations by: (i) showing that serially increasing NaCl concentration up to 200mM increased current linearly up to a total of þ273% vs. 0mM NaCl under advective conditions; (ii) growing the biofilm with a starting concentration of 200mM NaCl, which led to a maximum current increase of 400% vs. current generation without NaCl, and (iii) showing that un-colonized surface area remained even after steadystate current was reached. After accounting for iR effects, we confirmedmore » that the excess surface area existed despite a non-zero overpotential. The fact that the biofilm was constrained from colonizing and producing further current under these conditions confirmed the biofilms under study here were ion transport-limited. Our work demonstrates that the use of high surface area electrodes may not increase current density when the system design allows ion transport limitations to become dominant.« less

Convection and Solidification with Applications to Crystal Growth

NASA Technical Reports Server (NTRS)

DeVahl Davis, Graham

1994-01-01

An outline is given of research on the directional solidification of a liquid, and of the effects of natural convection thereon. Three problems which have been studied are described. Finally, current work on solidification in microgravity conditions is discussed.

Global precarious employment and health inequalities: working conditions, social class, or precariat?

PubMed

Muntaner, Carles

2016-06-20

Changes in employment conditions since the 1980s have been referred to as precarious employment, and terms like flexible, atypical, temporary, part-time, contract, self-employed, irregular, or non-standard employment have also been used. In this essay I review some of the current critiques to the precarious employment construct and advance some potential solutions for its use in epidemiology and public health.

The Value of Biomedical Simulation Environments to Future Human Space Flight Missions

NASA Technical Reports Server (NTRS)

Mulugeta, Lealem; Myers, Jerry G.; Skytland, Nicholas G.; Platts, Steven H.

2010-01-01

With the ambitious goals to send manned missions to asteroids and onto Mars, substantial work will be required to ensure the well being of the men and women who will undertake these difficult missions. Unlike current International Space Station or Shuttle missions, astronauts will be required to endure long-term exposure to higher levels of radiation, isolation and reduced gravity. These new operation conditions will pose health risks that are currently not well understood and perhaps unanticipated. Therefore, it is essential to develop and apply advanced tools to predict, assess and mitigate potential hazards to astronaut health. NASA s Digital Astronaut Project (DAP) is working to develop and apply computational models of physiologic response to space flight operation conditions over various time periods and environmental circumstances. The collective application and integration of well vetted models assessing the physiology, biomechanics and anatomy is referred to as the Digital Astronaut. The Digital Astronaut simulation environment will serve as a practical working tool for use by NASA in operational activities such as the prediction of biomedical risks and functional capabilities of astronauts. In additional to space flight operation conditions, DAP s work has direct applicability to terrestrial biomedical research by providing virtual environments for hypothesis testing, experiment design, and to reduce animal/human testing. A practical application of the DA to assess pre and post flight responses to exercise is illustrated and the difficulty in matching true physiological responses is discussed.

[Third working conditions and health survey in Navarre, Spain: main findings].

PubMed

García, Vega

To describe health problems and working conditions perceived by workers of Navarra, Spain. Conduct of the Third Survey of Working Conditions and Health in Navarre. We administered the Seventh Spanish National Survey of Working Conditions questionnaire by personal interviews conducted in the workers' homes between October 2014 and December 2014, and using a three-stage stratified sampling approach, by economic activity, work establishment size and gender. A total of 2744 interviews were completed, with a confidence level of 95.5% and P=Q, error ± 1.99. The analysis was weighted by the sampling variables. The results were summarized as percentages for qualitative variables and point estimates for quantitative variables. Among the postivie findings, 85% of respondents were well informed of job risks, 68% had access to a health and safety representative, 50% underwent risk assessments and 60% received periodic medical examinations. Among the notable self-reported occupational risk factors were exposure to loud noise (16%), chemicals (33%), accident-prone situations (76%), repetitive movements (62%), awkward postures (41%) and biological agents (11%). Issues of concern include a high percentage of overtime work (44% of men and 39% of women), feelings of being overworked (30.6% and 29.4%, respectively) and exposure to abusive behaviors (11.7% for verbal abuse), especially among women, healthcare workers and teachers. The most prevalent health problems were musculoskeletal (49% reporting back pain) and issues related to work stress (20%). The current working conditions in Navarre feature improved preventive services, persistence of traditional occupational risk factors and emergence of new issues such as violence and work stressors. Copyright belongs to the Societat Catalana de Salut Laboral.

Effects of working memory load on visual selective attention: behavioral and electrophysiological evidence.

PubMed

Pratt, Nikki; Willoughby, Adrian; Swick, Diane

2011-01-01

Working memory and attention interact in a way that enables us to focus on relevant items and maintain current goals. The influence of working memory on attention has been noted in several studies using dual task designs. Multitasking increases the demands on working memory and reduces the amount of resources available for cognitive control functions such as resolving stimulus conflict. However, few studies have investigated the temporal activation of the cortex while multitasking. The present study addresses the extent to which working memory load influences early (P1) and late (P300) attention-sensitive event-related potential components using a dual task paradigm. Participants performed an arrow flanker task alone (single task condition) or concurrently with a Sternberg memory task (dual task condition). In the flanker task, participants responded to the direction of a central arrow surrounded by congruent or incongruent arrows. In the dual task condition, participants were presented with a Sternberg task that consisted of either four or seven consonants to remember prior to a short block of flanker trials. Participants were slower and less accurate on incongruent versus congruent trials. Furthermore, accuracy on incongruent trials was reduced in both dual task conditions. Likewise, P300 amplitude to incongruent flanker stimuli decreased when working memory load increased. These findings suggest that interference from incongruent flankers was more difficult to suppress when working memory was taxed. In addition, P1 amplitude was diminished on all flanker trials in the dual task condition. This result indicates that top-down attentional control over early visual processing is diminished by increasing demands on working memory. Both the behavioral and electrophysiological results suggest that working memory is critical in maintaining attentional focus and resolving conflict.

Effects of Working Memory Load on Visual Selective Attention: Behavioral and Electrophysiological Evidence

PubMed Central

Pratt, Nikki; Willoughby, Adrian; Swick, Diane

2011-01-01

Working memory and attention interact in a way that enables us to focus on relevant items and maintain current goals. The influence of working memory on attention has been noted in several studies using dual task designs. Multitasking increases the demands on working memory and reduces the amount of resources available for cognitive control functions such as resolving stimulus conflict. However, few studies have investigated the temporal activation of the cortex while multitasking. The present study addresses the extent to which working memory load influences early (P1) and late (P300) attention-sensitive event-related potential components using a dual task paradigm. Participants performed an arrow flanker task alone (single task condition) or concurrently with a Sternberg memory task (dual task condition). In the flanker task, participants responded to the direction of a central arrow surrounded by congruent or incongruent arrows. In the dual task condition, participants were presented with a Sternberg task that consisted of either four or seven consonants to remember prior to a short block of flanker trials. Participants were slower and less accurate on incongruent versus congruent trials. Furthermore, accuracy on incongruent trials was reduced in both dual task conditions. Likewise, P300 amplitude to incongruent flanker stimuli decreased when working memory load increased. These findings suggest that interference from incongruent flankers was more difficult to suppress when working memory was taxed. In addition, P1 amplitude was diminished on all flanker trials in the dual task condition. This result indicates that top-down attentional control over early visual processing is diminished by increasing demands on working memory. Both the behavioral and electrophysiological results suggest that working memory is critical in maintaining attentional focus and resolving conflict. PMID:21716633

[Thermal load at workstations in the underground coal mining: Results of research carried out in 6 coal mines].

PubMed

Słota, Krzysztof; Słota, Zbigniew; Kułagowska, Ewa

Statistics shows that almost half of Polish extraction in underground mines takes place at workstations where temperature exceeds 28°C. The number of employees working in such conditions is gradually increasing, therefore, the problem of safety and health protection is still growing. In the present study we assessed the heat load of employees at different workstations in the mining industry, taking into account current thermal conditions and work costs. The evaluation of energy cost of work was carried out in 6 coal mines. A total of 221 miners employed at different workstations were assessed. Individual groups of miners were characterized and thermal safety of the miners was assessed relying on thermal discomfort index. The results of this study indicate considerable differences in the durations of analyzed work processes at individual workstations. The highest average energy cost was noted during the work performed in the forehead. The lowest value was found in the auxiliary staff. The calculated index of discomfort clearly indicated numerous situations in which the admissible range of thermal load exceeded the parameters of thermal load safe for human health. It should be noted that the values of average labor cost fall within the upper, albeit admissible, limits of thermal load. The results of the study indicate that in some cases work in mining is performed in conditions of thermal discomfort. Due to high variability and complexity of work conditions it becomes necessary to verify the workers' load at different workstations, which largely depends on the environmental conditions and work organization, as well as on the performance of workers themselves. Med Pr 2016;67(4):477-498. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

The Effects of Working at Gaining Employment Skills on the Social and Vocational Skills of Adolescents with Disabilities: A School-Based Intervention

ERIC Educational Resources Information Center

Murray, Christopher; Doren, Bonnie

2013-01-01

The current investigation was designed to evaluate the effects of the Working at Gaining Employment Skills (WAGES) curriculum on the social and occupational skills of adolescents with disabilities. Adolescents with disabilities were assigned to either an intervention or control condition. Youth in the intervention group were exposed to the WAGES…

Narrating the 1980s and 1990s: Voices of Poor and Working-Class White and African American Men.

ERIC Educational Resources Information Center

Weis, Lois; Fine, Michelle

1996-01-01

The divergent views of poor and working-class African-American and White men regarding the causes of their current condition are presented. Different "biographies of race" encourage African-American men to blame the economy and racism but White men to blame Black males for the economic plight of White men. The ways in which the two…

Unrestrained outsourcing in Brazil: more precarization and health risks for workers.

PubMed

Druck, Graça

2016-06-20

This article discusses the current status of outsourcing in Brazil, with new regulation underway featuring a bill of law under review by the National Congress, aimed at allowing outsourcing for all activities. The authors argue that outsourcing and precarization of work are inseparable phenomena, based on the results of 20 years of research in Brazil that reveals the more precarious working conditions of outsourced workers in different occupational categories. They focus particularly on workers' health: outsourcing of risks has led to more fatal work accidents, invariably at higher rates in outsourced workers. Finally, the article contends that to remove restraints on outsourcing in Brazil amounts to legalizing and legitimizing predatory workforce exploitation, disregarding workers' physical limits, exposing them to risk of fatal accidents, and reverting to forms of work that violate the human condition.

Learning at work: competence development or competence-stress.

PubMed

Paulsson, Katarina; Ivergård, Toni; Hunt, Brian

2005-03-01

Changes in work and the ways in which it is carried out bring a need for upgrading workplace knowledge, skills and competencies. In today's workplaces, and for a number of reasons, workloads are higher than ever and stress is a growing concern (Health Risk Soc. 2(2) (2000) 173; Educat. Psychol. Meas. 61(5) (2001) 866). Increased demand for learning brings a risk that this will be an additional stress factor and thus a risk to health. Our research study is based on the control-demand-support model of Karasek and Theorell (Health Work: Stress, Productivity and the Reconstruction of Working Life, Basic Books/Harper, New York, 1990). We have used this model for our own empirical research with the aim to evaluate the model in the modern workplace. Our research enables us to expand the model in the light of current workplace conditions-especially those relating to learning. We report empirical data from a questionnaire survey of working conditions in two different branches of industry. We are able to define differences between companies in terms of working conditions and competence development. We describe and discuss the effects these conditions have on workplace competence development. Our research results show that increased workers' control of the learning process makes competence development more stimulating, is likely to simplify the work and reduces (learning-related) stress. It is therefore important that learning at work allows employees to control their learning and also allows time for the process of learning and reflection.

Preference conditioning in healthy individuals: correlates with hazardous drinking.

PubMed

Balodis, Iris M; Lockwood, Kathleen P; Magrys, Sylvia A; Olmstead, Mary C

2010-06-01

Conditioned reward is a classic measure of drug-induced brain changes in animal models of addiction. The process can be examined in humans using the Conditioned Pattern Preference (CPP) task, in which participants associate nonverbal cues with reward but demonstrate low awareness of this conditioning. Previously, we reported that alcohol intoxication does not affect CPP acquisition in humans, but our data indicated that prior drug use may impact conditioning scores. To test this possibility, the current study examined the relationship between self-reported alcohol use and preference conditioning in the CPP task. Working memory was assessed during conditioning by asking participants to count the cues that appeared at each location on a computer screen. Participants (69 female and 23 male undergraduate students) completed the Alcohol Use Disorders Identification Test (AUDIT) and the Rutgers Alcohol Problem Index (RAPI) as measures of hazardous drinking. Self-reported hazardous drinking was significantly correlated with preference conditioning in that individuals who scored higher on these scales exhibited an increased preference for the reward-paired cues. In contrast, hazardous drinking did not affect working memory errors on the CPP task. These findings support evidence that repeated drug use sensitizes neural pathways mediating conditioned reward and point to a neurocognitive disposition linking substance misuse and responses to reward-paired stimuli. The relationship between hazardous drinking and conditioned reward is independent of changes in cognitive function, such as working memory.

Quits and job changes among home care workers in Maine: the role of wages, hours, and benefits.

PubMed

Morris, Lisa

2009-10-01

Figuring out how to make home care jobs more attractive has become a top policy priority. This study investigates the impact of wages, hours, and benefits on the retention of home care workers. Using a 2-wave survey design and a sample of home care workers from Maine, the factors associated with turnover intentions, actual turnover, and job-to-job transitions are examined. The analysis uses actual data on hours, wages, and benefits at current and subsequent jobs and controls for perceived rewards and work conditions, personal characteristics, and local labor market conditions. Although the analysis finds that improved work conditions and non-pecuniary rewards of home-based direct care work have significant negative effects on turnover intentions, compensation accounts for more actual job turnover. Higher wages, more hours, and travel cost reimbursement are found to be significantly associated with reduced turnover. Although wages and hours appear to have stronger effects, health benefits do appear to have some significance in predicting job-to-job transitions. Although improving compensation presents budgetary challenges to home care agencies, for this low-income workforce, the ability to earn higher wages and work more hours may be more of an imperative than improved work conditions.

Precarious employment and health: analysis of the Comprehensive National Survey in Japan.

PubMed

Tsurugano, Shinobu; Inoue, Mariko; Yano, Eiji

2012-01-01

Recent studies suggest that unstable employment contracts may affect the health of workers. Many Japanese workers working full time in ostensibly permanent positions actually operate within unstable and precarious employment conditions. We compared the health status of Japanese workers with precarious employment contracts with that of permanent workers using the 2007 Comprehensive Survey of Living Conditions of the People on Health and Welfare (n=205,994). We classified their employment status as 'permanent' vs. 'precarious' (part-time, dispatch, or contract/non-regular) and compared their health conditions. Among both sexes, precarious workers were more likely than permanent workers to have poor self-rated health or more subjective symptoms, with more workers in full-time employment suffering from serious psychological distress (SPD) and more female workers who smoke. Using logistic regression, we identified a positive association between precarious employment and SPD and current smoking among workers engaged in full-time employment after adjusting for age, marital status, and work-related conditions. This study demonstrates that precarious employment contracts are associated with poor self-rated health, psychological distress, and tobacco use, especially among people working full-time jobs. These results suggest that engagement in full-time work under unstable employment status impairs workers' health.

Enhancing Motivation for Learning and Work.

ERIC Educational Resources Information Center

Kirkhorn, Judith

1988-01-01

Discusses motivation based on adult learning conditions, and suggests appropriate motivation plans for leaders and trainers that will enhance performance. The steps to develop motivation plans include assessing current thinking on motivation and reinforcement options; objectively describing expected behaviors; and developing motivational…

Positive current collector for Li||Sb-Pb liquid metal battery

NASA Astrophysics Data System (ADS)

Ouchi, Takanari; Sadoway, Donald R.

2017-07-01

Corrosion in grid-scale energy storage devices adversely affects service lifetime and thus has a significant economic impact on their deployment. In this work, we investigate the corrosion of steel and stainless steels (SSs) as positive current collectors in the Li||Sb-Pb liquid metal battery. The erosion and formation of new phases on low-carbon steel, SS301, and SS430 were evaluated both in static conditions and under cell operating conditions. The cell performance is not adversely affected by the dissolution of iron or chromium but rather nickel. Furthermore, the in situ formation of a Fe-Cr-Sb layer helps mitigate the recession of SS430.

Working conditions survey and trainees situation: new approach to auditing the situation of European trainees in obstetrics and gynaecology ten years later.

PubMed

Rodríguez, David; Christopoulos, Panagiotis; Martins, Nuno; Pärgmäe, Pille; Werner, Henrica M J

2009-12-01

(1) To review the training and working conditions for trainees in obstetrics and gynaecology (Ob/Gyn) in Europe. (2) To suggest further improvements in working conditions for trainees in Ob/Gyn. It is an observational, descriptive, and cross-sectional study. The sample is constituted of the answers from the representatives of 25 European Network of Trainees in Ob/Gyn (ENTOG) member countries to a survey designed by ENTOG's executive. The current survey is based on the former ENTOG working conditions survey published in 1997, but has been extended to include questions that have become important recently, and to include new countries that have entered the European Union (EU) since that time. The total number of trainees represented in this study is 6056. The male/female ratio is 35/65. The average number of official working hours is 51.6 h weekly, but varies widely. The average number of duties/month is five, but varies widely from two to nine. Fewer than 50% of countries have a hospital visitation system implemented. Training abroad is possible in most training systems. Compared with the 1997 survey further harmonisation is taking place. Steps towards harmonisation are being made. Hospital visitation systems should be further introduced. Not all countries have remunerated training posts. Assessment should become more homogeneous. Compliance with the European Working Time Directive (EWTD) is a big challenge.

Calcium dependent current recordings in Xenopus laevis oocytes in microgravity

NASA Astrophysics Data System (ADS)

Wuest, Simon L.; Roesch, Christian; Ille, Fabian; Egli, Marcel

2017-12-01

Mechanical unloading by microgravity (or weightlessness) conditions triggers profound adaptation processes at the cellular and organ levels. Among other mechanisms, mechanosensitive ion channels are thought to play a key role in allowing cells to transduce mechanical forces. Previous experiments performed under microgravity have shown that gravity affects the gating properties of ion channels. Here, a method is described to record a calcium-dependent current in native Xenopus laevis oocytes under microgravity conditions during a parabolic flight. A 3-voltage-step protocol was applied to provoke a calcium-dependent current. This current increased with extracellular calcium concentration and could be reduced by applying extracellular gadolinium. The custom-made ;OoClamp; hardware was validated by comparing the results of the 3-voltage-step protocol to results obtained with a well-established two-electrode voltage clamp (TEVC). In the context of the 2nd Swiss Parabolic Flight Campaign, we tested the OoClamp and the method. The setup and experiment protocol worked well in parabolic flight. A tendency that the calcium-dependent current was smaller under microgravity than under 1 g condition could be observed. However, a conclusive statement was not possible due to the small size of the data base that could be gathered.

[Formation of working conditions and the problems of hygienic assessment of industrial environmental factors in railway tunnels].

PubMed

Kurenkova, G V; Lemeshevskaya, E P

Tunnels are an integral part of the ways and artificial constructions of the railway. Objective assessment of working conditions is important, because current regulations fail to allow to give a definite hygienic assessment of some factors of the production environment of the tunnels. Objective: to reveal the peculiarities of the formation of working conditions in railway tunnels with the subsequent hygienic assessment for the development of preventive measures. Measurement of the factors of working process and working environment is carried out with the use of the certified equipment for the approved the hygienic and sanitary-chemical methods in workplaces in tunnels of the East-Siberian railway. Specific conditions were shown to be formed due to constructive solutions, climate and geographical location, the length of railway tunnels, the composition of the rocks through which the tunnel, the nature of the maintenance tunnels, ventilation system, repetition rate and type of passing rolling stock. All employees from occupational groups from examined tunnels were established to be exposed to high concentrations of aerosols with predominantly fibrogenic action, noise levels, adverse climate (low positive and negative temperatures, high relative humidity and mobility of air), the lack of natural lighting, low levels of artificial light, hard exertion of labor (dynamic physical load, working position, the slopes of the body, movement in space). Additionally, high levels of the vibration, nonionizing and ionizing radiation were typical for jobs of the Baikal and the North-Muya tunnel. There is proposed the algorithm of hygienic assessment of the microclimate, light environment at the working places depending on the time of the works in the underground conditions and constructional features of tunnels, methods of accounting personnel dose rates from natural sources.

Galvanic corrosion of nitinol under deaerated and aerated conditions.

PubMed

Pound, Bruce G

2016-10-01

Various studies have examined the corrosion rate of nitinol generally under deaerated conditions. Likewise, galvanic corrosion studies have typically involved deaerated solutions. This work addressed the effect of galvanic coupling on the corrosion current of electropolished nitinol in phosphate buffered saline and 0.9% sodium chloride under dearated and aerated conditions for times up to 24 h. Tests were performed on nitinol alone and coupled with MP35N in both the mechanically polished and passivated conditions. Aeration and galvanic coupling were found to have relatively little effect, indicating that the corrosion current is controlled by the anodic reaction. The current can be attributed entirely to Ni(2+) dissolution, which appears to be governed by solid-state mass transport of Ni(2+) through the passive oxide film. Because corrosion of EP nitinol is controlled by the anodic reaction, contact between EP nitinol and MP35N or other biomedical Co-Cr alloys is unlikely to result in significant galvanic effects in vivo. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1322-1327, 2016. © 2015 Wiley Periodicals, Inc.

Health Behaviors and Overweight in Nursing Home Employees: Contribution of Workplace Stressors and Implications for Worksite Health Promotion.

PubMed

Miranda, Helena; Gore, Rebecca J; Boyer, Jon; Nobrega, Suzanne; Punnett, Laura

2015-01-01

Many worksite health promotion programs ignore the potential influence of working conditions on unhealthy behaviors. A study of nursing home employees (56% nursing aides) utilized a standardized questionnaire. We analyzed the cross-sectional associations between workplace stressors and obesity, cigarette smoking, and physical inactivity. Of 1506 respondents, 20% reported exposure to three or more workplace stressors (physical or organizational), such as lifting heavy loads, low decision latitude, low coworker support, regular night work, and physical assault. For each outcome, the prevalence ratio was between 1.5 and 2 for respondents with four or five job stressors. Individuals under age 40 had stronger associations between workplace stressors and smoking and obesity. Workplace stressors were strongly associated with smoking, obesity, and physical inactivity, even among the lowest-status workers. Current working conditions affected younger workers more than older workers. Although this study is cross-sectional, it has other strengths, including the broad range of work stressors studied. Strenuous physical work and psychosocial strain are common among low-wage workers such as nursing home aides. Workplace health promotion programs may be more effective if they include measures to reduce stressful work environment features, so that working conditions support rather than interfere with employee health.

Health Behaviors and Overweight in Nursing Home Employees: Contribution of Workplace Stressors and Implications for Worksite Health Promotion

PubMed Central

Miranda, Helena; Gore, Rebecca J.; Boyer, Jon; Nobrega, Suzanne; Punnett, Laura

2015-01-01

Background. Many worksite health promotion programs ignore the potential influence of working conditions on unhealthy behaviors. Methods. A study of nursing home employees (56% nursing aides) utilized a standardized questionnaire. We analyzed the cross-sectional associations between workplace stressors and obesity, cigarette smoking, and physical inactivity. Results. Of 1506 respondents, 20% reported exposure to three or more workplace stressors (physical or organizational), such as lifting heavy loads, low decision latitude, low coworker support, regular night work, and physical assault. For each outcome, the prevalence ratio was between 1.5 and 2 for respondents with four or five job stressors. Individuals under age 40 had stronger associations between workplace stressors and smoking and obesity. Conclusions. Workplace stressors were strongly associated with smoking, obesity, and physical inactivity, even among the lowest-status workers. Current working conditions affected younger workers more than older workers. Although this study is cross-sectional, it has other strengths, including the broad range of work stressors studied. Strenuous physical work and psychosocial strain are common among low-wage workers such as nursing home aides. Workplace health promotion programs may be more effective if they include measures to reduce stressful work environment features, so that working conditions support rather than interfere with employee health. PMID:26380373

The Utrecht approach to exercise in chronic childhood conditions: the decade in review.

PubMed

van Brussel, Marco; van der Net, Janjaap; Hulzebos, Erik; Helders, Paul J M; Takken, Tim

2011-01-01

To summarize and discuss current evidence and understanding of clinical pediatric exercise physiology focusing on the work the research group at Utrecht and others have performed in the last decade in a variety of chronic childhood conditions as a continuation of the legacy of Dr Bar-Or. The report discusses current research findings on the cardiopulmonary exercise performance of children (and adolescents) with juvenile idiopathic arthritis, osteogenesis imperfecta, achondroplasia, hemophilia, cerebral palsy, spina bifida, cystic fibrosis, and childhood cancer. Exercise recommendations and contraindications are provided for each condition. Implications for clinical practice and future research in this area are discussed for each of the chronic conditions presented. The authors provide a basic framework for developing an individual and/or disease-specific training program, introduce the physical activity pyramid, and recommend a core set of clinical measures to be used in clinical research.

Social Stress at Work and Change in Women’s Body Weight

PubMed Central

KOTTWITZ, Maria U.; GREBNER, Simone; SEMMER, Norbert K.; TSCHAN, Franziska; ELFERING, Achim

2014-01-01

Social stressors at work (such as conflict or animosities) imply disrespect or a lack of appreciation and thus a threat to self. Stress induced by this offence to self might result, over time, in a change in body weight. The current study investigated the impact of changing working conditions —specifically social stressors, demands, and control at work— on women’s change in weighted Body-Mass-Index over the course of a year. Fifty-seven women in their first year of occupational life participated at baseline and thirty-eight at follow-up. Working conditions were assessed by self-reports and observer-ratings. Body-Mass-Index at baseline and change in Body-Mass-Index one year later were regressed on self-reported social stressors as well as observed work stressors, observed job control, and their interaction. Seen individually, social stressors at work predicted Body-Mass-Index. Moreover, increase in social stressors and decrease of job control during the first year of occupational life predicted increase in Body-Mass-Index. Work redesign that reduces social stressors at work and increases job control could help to prevent obesity epidemic. PMID:24429516

Original research: New nurses: has the recession increased their commitment to their jobs?

PubMed

Brewer, Carol S; Kovner, Christine T; Yingrengreung, Siritorn; Djukic, Maja

2012-03-01

Current evidence suggests that the economic recession has induced retired RNs to reenter nursing and working nurses to work more hours and delay retirement, thus easing the projected RN shortage. We wondered whether the economic downturn had affected new nurses' work attitudes and behaviors, including those related to turnover. The purpose of this study was to compare perceptions about job opportunities, as well as key attitudinal variables (such as job satisfaction and intent to stay), in two cohorts of newly licensed RNs. Our data came from two sources: a subset of new RNs licensed between August 1, 2004, and July 31, 2005, who were part of a larger 2006 study on turnover, and a later cohort of new RNs licensed between August 1, 2007, and July 31, 2008. We mailed survey questionnaires to one cohort before the recession in 2006 and to a second cohort during the recession in 2009. We found that RNs' commitment to their current employers was higher in the later cohort than in the earlier one, although neither nurses' incomes nor their reported job satisfaction levels had changed. Our findings suggest that, despite some improvements in working conditions, newly licensed RNs may just be waiting for the recession to end before changing jobs. Health care organizations' efforts to improve RNs' working conditions and wages, and to implement or support existing programs aimed at increasing retention, should be continued.

Improved equivalent magnetic network modeling for analyzing working points of PMs in interior permanent magnet machine

NASA Astrophysics Data System (ADS)

Guo, Liyan; Xia, Changliang; Wang, Huimin; Wang, Zhiqiang; Shi, Tingna

2018-05-01

As is well known, the armature current will be ahead of the back electromotive force (back-EMF) under load condition of the interior permanent magnet (PM) machine. This kind of advanced armature current will produce a demagnetizing field, which may make irreversible demagnetization appeared in PMs easily. To estimate the working points of PMs more accurately and take demagnetization under consideration in the early design stage of a machine, an improved equivalent magnetic network model is established in this paper. Each PM under each magnetic pole is segmented, and the networks in the rotor pole shoe are refined, which makes a more precise model of the flux path in the rotor pole shoe possible. The working point of each PM under each magnetic pole can be calculated accurately by the established improved equivalent magnetic network model. Meanwhile, the calculated results are compared with those calculated by FEM. And the effects of d-axis component and q-axis component of armature current, air-gap length and flux barrier size on working points of PMs are analyzed by the improved equivalent magnetic network model.

Psychosocial job conditions, fear avoidance beliefs and expected return to work following acute coronary syndrome: a cross-sectional study of fear-avoidance as a potential mediator.

PubMed

Söderberg, Mia; Rosengren, Annika; Gustavsson, Sara; Schiöler, Linus; Härenstam, Annika; Torén, Kjell

2015-12-21

Despite improvements in treatment, acute coronary syndrome remains a substantial cause for prolonged sick absences and premature retirement. Knowledge regarding what benefits return to work is limited, especially the effect of psychological processes and psychosocial work factors. The purposes of this cross-sectional study were two-fold: to examine associations between adverse psychosocial job conditions and fear-avoidance beliefs towards work, and to determine whether such beliefs mediated the relationship between work conditions and expected return to work in acute coronary syndrome survivors. Study inclusion criteria: acute myocardial infarction or unstable angina diagnosis, below 65 years of age, being a resident in the West county of Sweden and currently working. In all, 509 individuals (21.8 % women) accepted study participation and for whom all data of study interest were available for analysis. Psychosocial work variables; job demand-control and effort-reward imbalance, were assessed with standard questionnaire batteries. Linear regression models were used to investigate relationships between psychosocial factors and fear-avoidance, and to evaluate mediator effects for fear-avoidance. Both total sample and gender stratified analyses were calculated. Fear-avoidance beliefs about work were associated to psychosocial job environments characterized by high strain (β 1.4; CI 1.2-1.6), active and passive work and high effort-reward imbalance (β 0.6; CI 0.5-0.7). Further, such beliefs also mediated the relationship between adverse work conditions and expected time for return to work. However, these results were only observed in total sample analyses or among or male participants. For women only high strain was linked to fear-avoidance, and these relationships became non-significant when entering chosen confounders. This cross-sectional study showed that acute coronary syndrome survivors, who laboured under adverse psychosocial work conditions, held fear-avoidance beliefs towards their workplace. Furthermore, these beliefs mediated the relationships between - high strained or high effort-reward imbalanced work - and expected return to work. However, mentioned results were primarily found among men, which could results from few female study participants or gender differences in return to work mechanisms. Still, an earlier return to work might be promoted by interventions focusing on improved psychosocial work conditions and cognitive behavioural therapy targeting fear-avoidance beliefs.

[Job crisis and transformations in the new model of accumulation].

PubMed

Zerda-Sarmiento, Alvaro

2012-06-01

The general and structural crisis capitalism is going through is the token of the difficulties accumulation model has been dealing with since 70's in developed countries. This model has been trying to settle down again on the basis of neoliberal principle and a new technical-economical paradigm. The new accumulation pattern has had a effect in employment sphere which have been made evident at all the elements that constitute work relationships. In Colombia, this model implementation has been partial and segmented. However, its consequences (and the long-term current crisis) have been evident in unemployment, precarious work, segmentation, informal work and restricted and private health insurance. Besides, financial accumulation makes labour profits flow at different levels. The economic model current government has aimed to implement leads to strengthening exports, so making population life conditions more difficult. In order to overcome the current state of affairs, the work sphere needs to become more creative. This creative approach should look for new schemes for expression and mobilization of work sphere's claims. This is supposed to be done by establishing a different economic model aimed to build a more inclusive future, with social justice.

Surface currents on the plasma-vacuum interface in MHD equilibria

NASA Astrophysics Data System (ADS)

Hanson, James D.

2016-10-01

The VMEC non-axisymmetric MHD equilibrium code can compute free-boundary equilibria. Since VMEC assumes that magnetic fields within the plasma form closed and nested flux surfaces, the plasma-vacuum interface is a flux surface, and the total magnetic field there has no normal component. VMEC imposes this condition of zero normal field using the potential formulation of Merkel, and solves a Neumann problem for the magnetic potential in the exterior region. This boundary condition necessarily admits the possibility of a surface current on the plasma-vacuum interface. While this current may be small in MHD equilibrium, this current may be readily computed in terms of a magnetic potential in both the interior and exterior regions. Examples of the surface current for VMEC equilibria will be shown. This material is based upon work supported by Auburn University and the U.S. Department of Energy, Office of Science, Office of Fusion Energy Sciences under Award Number DE-FG02-03ER54692.

Nursing overtime: why, how much, and under what working conditions?

PubMed

Bae, Sung-Heui

2012-01-01

To provide the best care to patients, the physical wellness of nursing staff is essential. Current evidence indicates long work hours can lead to adverse nurse and patient outcomes. To provide quality and safe patient care, both staff nurses and nurse managers need to recognize the adverse effects of overtime, whether it is mandatory or voluntary. Results of this study showed overtime was not used more when there was an increase in nursing shortages. Further, overtime was not used to control shortages; rather, understaffing was an underlying condition of the nursing practice, at least in the study sample. Thus, efforts must be made not only to prevent nurses from working long hours, but also to resolve the problem of understaffing in order to retain qualified nurses in hospitals.

Toward Improved CFD Predictions of Slender Airframe Aerodynamics Using the F-16XL Aircraft (CAWAPI-2)

NASA Technical Reports Server (NTRS)

Luckring, James M.; Rizzi, Arthur; Davis, M. Bruce

2014-01-01

A coordinated project has been underway to improve CFD predictions of slender airframe aerodynamics. The work is focused on two flow conditions and leverages a unique flight data set obtained with an F-16XL aircraft. These conditions, a low-speed high angleof- attack case and a transonic low angle-of-attack case, were selected from a prior prediction campaign wherein the CFD failed to provide acceptable results. In this paper the background, objectives and approach to the current project are presented. The work embodies predictions from multiple numerical formulations that are contributed from multiple organizations, and the context of this campaign to other multi-code, multiorganizational efforts is included. The relevance of this body of work toward future supersonic commercial transport concepts is also briefly addressed.

A comparison of methods for teaching receptive language to toddlers with autism.

PubMed

Vedora, Joseph; Grandelski, Katrina

2015-01-01

The use of a simple-conditional discrimination training procedure, in which stimuli are initially taught in isolation with no other comparison stimuli, is common in early intensive behavioral intervention programs. Researchers have suggested that this procedure may encourage the development of faulty stimulus control during training. The current study replicated previous work that compared the simple-conditional and the conditional-only methods to teach receptive labeling of pictures to young children with autism spectrum disorder. Both methods were effective, but the conditional-only method required fewer sessions to mastery. © Society for the Experimental Analysis of Behavior.

Behavior data of battery and battery pack SOC estimation under different working conditions.

PubMed

Zhang, Xu; Wang, Yujie; Yang, Duo; Chen, Zonghai

2016-12-01

This article provides the dataset of operating conditions of battery behavior. The constant current condition and the dynamic stress test (DST) condition were carried out to analyze the battery discharging and charging features. The datasets were achieved at room temperature, in April, 2016. The shared data contributes to clarify the battery pack state-of-charge (SOC) and the battery inconsistency, which is also shown in the article of "An on-line estimation of battery pack parameters and state-of-charge using dual filters based on pack model" (X. Zhang, Y. Wang, D. Yang, et al., 2016) [1].

Climate Twins - a tool to explore future climate impacts by assessing real world conditions: Exploration principles, underlying data, similarity conditions and uncertainty ranges

NASA Astrophysics Data System (ADS)

Loibl, Wolfgang; Peters-Anders, Jan; Züger, Johann

2010-05-01

To achieve public awareness and thorough understanding about expected climate changes and their future implications, ways have to be found to communicate model outputs to the public in a scientifically sound and easily understandable way. The newly developed Climate Twins tool tries to fulfil these requirements via an intuitively usable web application, which compares spatial patterns of current climate with future climate patterns, derived from regional climate model results. To get a picture of the implications of future climate in an area of interest, users may click on a certain location within an interactive map with underlying future climate information. A second map depicts the matching Climate Twin areas according to current climate conditions. In this way scientific output can be communicated to the public which allows for experiencing climate change through comparison with well-known real world conditions. To identify climatic coincidence seems to be a simple exercise, but the accuracy and applicability of the similarity identification depends very much on the selection of climate indicators, similarity conditions and uncertainty ranges. Too many indicators representing various climate characteristics and too narrow uncertainty ranges will judge little or no area as regions with similar climate, while too little indicators and too wide uncertainty ranges will address too large regions as those with similar climate which may not be correct. Similarity cannot be just explored by comparing mean values or by calculating correlation coefficients. As climate change triggers an alteration of various indicators, like maxima, minima, variation magnitude, frequency of extreme events etc., the identification of appropriate similarity conditions is a crucial question to be solved. For Climate Twins identification, it is necessary to find a right balance of indicators, similarity conditions and uncertainty ranges, unless the results will be too vague conducting a useful Climate Twins regions search. The Climate Twins tool works actually comparing future climate conditions of a certain source area in the Greater Alpine Region with current climate conditions of entire Europe and the neighbouring southern as well south-eastern areas as target regions. A next version will integrate web crawling features for searching information about climate-related local adaptations observed today in the target region which may turn out as appropriate solution for the source region under future climate conditions. The contribution will present the current tool functionally and will discuss which indicator sets, similarity conditions and uncertainty ranges work best to deliver scientifically sound climate comparisons and distinct mapping results.

Women: work and health.

PubMed

Wagener, D K; Walstedt, J; Jenkins, L; Burnett, C; Lalich, N; Fingerhut, M

1997-12-01

This report describes the sociodemographics, household characteristics, and health of women according to workforce status and job conditions. The report also presents data on men for comparison. This report combines data from numerous data systems, including: The National Health Interview Survey, National Health and Nutrition Examination Survey, National Maternal and Infant Health Survey, National Hospital Ambulatory Medical Care Survey, National Traumatic Occupational Fatalities Surveillance System, and the National Occupational Mortality Surveillance System, which are conducted by the U.S. Department of Health and Human Services; the Census of Fatal Occupational Injuries and Annual Survey of Occupational injuries and illnesses conducted by the U.S. Department of Labor; and the Current Population Survey conducted by the U.S. Department of Commerce. The report also presents selected tables from publications of the Women's Bureau and the Bureau of Labor Statistics, U.S. Department of Labor. The report presents summary data on physical conditions and exposures, health conditions attributed to work, other health conditions that impact on work, health promotion in the workplace, and health-related benefits provided by employers. Most estimates are shown according to sex, age, race, ethnicity, educational attainment, and major occupational group.

Work-family interface from a life and career stage perspective: the role of demands and resources.

PubMed

Demerouti, Evangelia; Peeters, Maria C W; van der Heijden, Beatrice I J M

2012-01-01

Work-family conflict and enrichment are experiences that occur daily and have substantial consequences for employees, their families, and the organizations that employ them. The aim of the current review is to make a link between life and career stage, work and family conditions, and the work-family interface. The basic proposition is that life stages partly determine career development, and consequently the specific working conditions (job demands and job resources) and family conditions (family demands and family resources) that individuals are exposed to. As a result, the specific demands and resources in the work and family domains determine to what extent individuals experience that work and family are conflicting or enriching life domains. In this review we suggest that individuals in early adulthood will experience high inter-role conflict and low facilitation due to high demands and low resources in both life domains, while individuals in late adulthood will experience the opposite pattern; that is, low conflict and high facilitation due to low demands and high resources in both domains. Individuals in middle adulthood will experience high work-family conflict but also high family-work facilitation due to the presence of high job demands and resources in both life domains. Integrating life and career stage perspectives and the experience of work-family interface is of notable practical utility because it provides a mechanism to make more informed decisions about the relative need for and corresponding benefits of work-family programs.

The Effects of Age, Priming, and Working Memory on Decision-Making.

PubMed

Wood, Meagan; Black, Sheila; Gilpin, Ansley

2016-01-11

In the current study, we examined the effects of priming and personality on risky decision-making while playing the Game of Dice Task (GDT). In the GDT, participants decide how risky they wish to be on each trial. In this particular study prior to playing the GDT, participants were randomly assigned to one of three priming conditions: Risk-Aversive, Risk-Seeking, or Control. In the Risk-Seeking condition, a fictional character benefitted from risky behavior while in the Risk-Aversive condition, a fictional character benefitted from exercising caution. Although not explicitly stated in the instructions, participants need to make "safe" rather than risky choices to optimize performance on the GDT. Participants were also given Daneman and Carpenter's assessment of working memory task. Interestingly, although older adults self-reported being more cautious than younger adults on the Domain Specific Risk Attitude scale (DOSPERT), older adults made riskier decisions than younger adults on the GDT. However, after controlling for working memory, the age differences on the GDT became insignificant, indicating that working memory mediated the relation between age and risky decisions on the GDT.

The Effects of Age, Priming, and Working Memory on Decision-Making

PubMed Central

Wood, Meagan; Black, Sheila; Gilpin, Ansley

2016-01-01

In the current study, we examined the effects of priming and personality on risky decision-making while playing the Game of Dice Task (GDT). In the GDT, participants decide how risky they wish to be on each trial. In this particular study prior to playing the GDT, participants were randomly assigned to one of three priming conditions: Risk-Aversive, Risk-Seeking, or Control. In the Risk-Seeking condition, a fictional character benefitted from risky behavior while in the Risk-Aversive condition, a fictional character benefitted from exercising caution. Although not explicitly stated in the instructions, participants need to make “safe” rather than risky choices to optimize performance on the GDT. Participants were also given Daneman and Carpenter’s assessment of working memory task. Interestingly, although older adults self-reported being more cautious than younger adults on the Domain Specific Risk Attitude scale (DOSPERT), older adults made riskier decisions than younger adults on the GDT. However, after controlling for working memory, the age differences on the GDT became insignificant, indicating that working memory mediated the relation between age and risky decisions on the GDT. PMID:26761023

The effect of acute aerobic and resistance exercise on working memory.

PubMed

Pontifex, Matthew B; Hillman, Charles H; Fernhall, Bo; Thompson, Kelli M; Valentini, Teresa A

2009-04-01

The goal of this investigation was to assess the influence of acute bouts of aerobic versus resistance exercise on the executive control of working memory. Twenty-one young adult participants completed a cardiorespiratory fitness test and maximal strength tests. On subsequent days, task performance measures of reaction time (RT) and accuracy were collected while participants completed a modified Sternberg working memory task before the start of, immediately after, and 30 min after an intervention consisting of 30 min of either resistance or aerobic exercise and a seated rest control. Findings indicated shorter RT immediately and 30 min after acute aerobic exercise relative to the preexercise baseline with no such effects observed after resistance exercise or seated rest. Further, in the aerobic condition, a larger reduction in RT from the baseline occurred during task conditions requiring increased working memory capacity. Again, no effect was observed in the resistance exercise or the seated rest conditions. These data extend the current knowledge base by indicating that acute exercise-induced changes in cognition are disproportionately related to executive control and may be specific to the aerobic exercise domain.

Physicians' perceptions of capacity building for managing chronic disease in seniors using integrated interprofessional care models.

PubMed

Lee, Linda; Heckman, George; McKelvie, Robert; Jong, Philip; D'Elia, Teresa; Hillier, Loretta M

2015-03-01

To explore the barriers to and facilitators of adapting and expanding a primary care memory clinic model to integrate care of additional complex chronic geriatric conditions (heart failure, falls, chronic obstructive pulmonary disease, and frailty) into care processes with the goal of improving outcomes for seniors. Mixed-methods study using quantitative (questionnaires) and qualitative (interviews) methods. Ontario. Family physicians currently working in primary care memory clinic teams and supporting geriatric specialists. Family physicians currently working in memory clinic teams (n = 29) and supporting geriatric specialists(n = 9) were recruited as survey participants. Interviews were conducted with memory clinic lead physicians (n = 16).Statistical analysis was done to assess differences between family physician ratings and geriatric specialist ratings related to the capacity for managing complex chronic geriatric conditions, the role of interprofessional collaboration within primary care, and funding and staffing to support geriatric care. Results from both study methods were compared to identify common findings. Results indicate overall support for expanding the memory clinic model to integrate care for other complex conditions. However, the current primary care structure is challenged to support optimal management of patients with multiple comorbidities, particularly as related to limited funding and staffing resources. Structured training, interprofessional teams, and an active role of geriatric specialists within primary care were identified as important facilitators. The memory clinic model, as applied to other complex chronic geriatric conditions, has the potential to build capacity for high-quality primary care, improve health outcomes,promote efficient use of health care resources, and reduce healthcare costs.

[Analyzing the attributes of surgeons and working environment required for a successful career path and work-life balance: results of a survey administered to doctors working at Kyoto University Hospital].

PubMed

Okoshi, Kae; Tanabe, Tomoko; Hisamoto, Norio; Sakai, Yoshiharu

2012-05-01

We conducted a survey in March 2010 of all physicians at Kyoto University Hospital on working environments, levels of satisfaction, and level of exhaustion. A comparison of surgeons with other physicians showed tendencies among surgeons toward longer working hours and lower income. The findings indicated that surgeons experienced satisfaction from teamwork with fellow physicians, opportunities to manage interesting cases, and patient gratitude. Surgeons tended to have low fatigue level and were satisfied with their working environments, despite their low wages and long working hours. Although surgical treatment is currently built upon the feelings of accomplishment and satisfaction of individual surgeons, there is always a limit to his/her psychological strength. Indeed, the number of young surgeons is not increasing. In the future, efforts must be taken to prevent the departure of currently practicing surgeons. Consideration must also be given to reducing nonsurgical duties by increasing the numbers of medical staff, and making work conditions more appealing to young surgeons by guaranteeing income and prohibiting long working hours, particularly consecutive working hours.

Fine motor movements while drawing during the encoding phase of a serial verbal recall task reduce working memory performance.

PubMed

Tindle, Richard; Longstaff, Mitchell G

2016-02-01

The time-based resource-sharing (TBRS) model of working memory indicates that secondary tasks that capture attention for relatively long periods can result in the interference of working memory processing and maintenance. The current study investigates if discrete and continuous movements have differing effects on a concurrent, verbal serial recall task. In the listening condition, participants were asked to recall spoken words presented in lists of six. In the drawing conditions, participants performed the same task while producing discrete (star) or continuous (circle) movements. As hypothesised, participants recalled more words overall in the listening condition compared to the combined drawing conditions. The prediction that the continuous movement condition would reduce recall compared to listening was also supported. Fine-grained analysis at each serial position revealed significantly more words were recalled at mid serial positions in the listening condition, with worst recall for the continuous condition at position 5 compared to the listening and discrete conditions. Kinematic analysis showed that participants increased the size and speed of the continuous movements resulting in a similar duration and number of strokes for each condition. The duration of brief pauses in the discrete condition was associated with the number of words recalled. The results indicate that fine motor movements reduced working memory performance; however, it was not merely performing a movement but the type of the movement that determined how resources were diverted. In the context of the TBRS, continuous movements could be capturing attention for longer periods relative to discrete movements, reducing verbal serial recall. Copyright © 2016 Elsevier B.V. All rights reserved.

Transient tracking of low and high-order eccentricity-related components in induction motors via TFD tools

NASA Astrophysics Data System (ADS)

Climente-Alarcon, V.; Antonino-Daviu, J.; Riera-Guasp, M.; Pons-Llinares, J.; Roger-Folch, J.; Jover-Rodriguez, P.; Arkkio, A.

2011-02-01

The present work is focused on the diagnosis of mixed eccentricity faults in induction motors via the study of currents demanded by the machine. Unlike traditional methods, based on the analysis of stationary currents (Motor Current Signature Analysis (MCSA)), this work provides new findings regarding the diagnosis approach proposed by the authors in recent years, which is mainly focused on the fault diagnosis based on the analysis of transient quantities, such as startup or plug stopping currents (Transient Motor Current Signature Analysis (TMCSA)), using suitable time-frequency decomposition (TFD) tools. The main novelty of this work is to prove the usefulness of tracking the transient evolution of high-order eccentricity-related harmonics in order to diagnose the condition of the machine, complementing the information obtained with the low-order components, whose transient evolution was well characterised in previous works. Tracking of high-order eccentricity-related harmonics during the transient, through their associated patterns in the time-frequency plane, may significantly increase the reliability of the diagnosis, since the set of fault-related patterns arising after application of the corresponding TFD tool is very unlikely to be caused by other faults or phenomena. Although there are different TFD tools which could be suitable for the transient extraction of these harmonics, this paper makes use of a Wigner-Ville distribution (WVD)-based algorithm in order to carry out the time-frequency decomposition of the startup current signal, since this is a tool showing an excellent trade-off between frequency resolution at both high and low frequencies. Several simulation results obtained with a finite element-based model and experimental results show the validity of this fault diagnosis approach under several faulty and operating conditions. Also, additional signals corresponding to the coexistence of the eccentricity and other non-fault related phenomena making difficult the diagnosis (fluctuating load torque) are included in the paper. Finally, a comparison with an alternative TFD tool - the discrete wavelet transform (DWT) - applied in previous papers, is also carried out in the contribution. The results are promising regarding the usefulness of the methodology for the reliable diagnosis of eccentricities and for their discrimination against other phenomena.

Effects of the Indianapolis Vocational Intervention Program (IVIP) on Defeatist Beliefs, Work Motivation, and Work Outcomes in Serious Mental Illness

PubMed Central

Mervis, Joshua E.; Fiszdon, Joanna M.; Lysaker, Paul H.; Nienow, Tasha M.; Mathews, Laura; Wardwell, Patricia; Petrik, Tammy; Thime, Warren; Choi, Jimmy

2016-01-01

Defeatist beliefs and amotivation are prominent obstacles in vocational rehabilitation for people with serious mental illnesses (SMI). The CBT-based Indianapolis Vocational Intervention Program (IVIP) was specifically designed to reduce defeatist beliefs related to work functioning. In the current study, we examined the impact of IVIP on defeatist beliefs and motivation for work, hypothesizing that IVIP would be associated with a reduction in defeatist beliefs and greater motivation for work. We also examined the effects of IVIP on these variables as well as work outcomes during a 12-month follow-up. Participants with SMI (n=64) enrolled in a four-month work therapy program were randomized to IVIP or a support therapy group (SG). Assessments were conducted at baseline, post-treatment (4 months), and follow-up (1 year). Compared to those in SG condition, individuals randomized to IVIP condition reported greater reductions in defeatist beliefs and greater motivation for work at follow-up, along with greater supported employment retention rates. Specifically treating and targeting negative expectations for work therapy improves outcomes, even once active supports of the IVIP program and work therapy are withdrawn. PMID:27802910

Effects of the Indianapolis Vocational Intervention Program (IVIP) on defeatist beliefs, work motivation, and work outcomes in serious mental illness.

PubMed

Mervis, Joshua E; Fiszdon, Joanna M; Lysaker, Paul H; Nienow, Tasha M; Mathews, Laura; Wardwell, Patricia; Petrik, Tammy; Thime, Warren; Choi, Jimmy

2017-04-01

Defeatist beliefs and amotivation are prominent obstacles in vocational rehabilitation for people with serious mental illnesses (SMI). The CBT-based Indianapolis Vocational Intervention Program (IVIP) was specifically designed to reduce defeatist beliefs related to work functioning. In the current study, we examined the impact of IVIP on defeatist beliefs and motivation for work, hypothesizing that IVIP would be associated with a reduction in defeatist beliefs and greater motivation for work. We also examined the effects of IVIP on these variables as well as work outcomes during a 12-month follow-up. Participants with SMI (n=64) enrolled in a four-month work therapy program were randomized to IVIP or a support therapy group (SG). Assessments were conducted at baseline, post-treatment (4months), and follow-up (1year). Compared to those in SG condition, individuals randomized to IVIP condition reported greater reductions in defeatist beliefs and greater motivation for work at follow-up, along with greater supported employment retention rates. Specifically treating and targeting negative expectations for work therapy improves outcomes, even once active supports of the IVIP program and work therapy are withdrawn. Copyright © 2016 Elsevier B.V. All rights reserved.

Age differences in proactive interference, working memory, and abstract reasoning

PubMed Central

Emery, Lisa; Hale, Sandra; Myerson, Joel

2008-01-01

It has been hypothesized that older adults are especially susceptible to proactive interference (PI), and that this may contribute to age differences in working memory performance. In young adults, individual differences in PI affect both working memory and reasoning ability, but the relations between PI, working memory, and reasoning in older adults have not been examined. In the current study, young, old, and very old adults performed a modified operation span task that induced several cycles of PI buildup and release, as well as two tests of abstract reasoning ability. Age differences in working memory scores increased as PI built up, consistent with the hypothesis that older adults are more susceptible to PI, but both young and older adults showed complete release from PI. Young adults' reasoning ability was best predicted by working memory performance under high-PI conditions, replicating Bunting (2006). In contrast, older adults' reasoning ability was best predicted by their working memory performance under low-PI conditions, thereby raising questions regarding the general role of susceptibility to PI in differences in higher cognitive function among older adults. PMID:18808252

Random Vibration Testing of Advanced Wet Tantalum Capacitors

NASA Technical Reports Server (NTRS)

Teverovsky, Alexander

2015-01-01

Advanced wet tantalum capacitors allow for improved performance of power supply systems along with substantial reduction of size and weight of the systems that is especially beneficial for space electronics. Due to launch-related stresses, acceptance testing of all space systems includes random vibration test (RVT). However, many types of advanced wet tantalum capacitors cannot pass consistently RVT at conditions specified in MIL-PRF-39006, which impedes their use in space projects. This requires a closer look at the existing requirements, modes and mechanisms of failures, specifics of test conditions, and acceptance criteria. In this work, different lots of advanced wet tantalum capacitors from four manufacturers have been tested at step stress random vibration conditions while their currents were monitored before, during, and after the testing. It has been shown that the robustness of the parts and their reliability are mostly due to effective self-healing processes and limited current spiking or minor scintillations caused by RVT do not increase the risk of failures during operation. A simple model for scintillations events has been used to simulate current spiking during RVT and optimize test conditions. The significance of scintillations and possible effects of gas generation have been discussed and test acceptance criteria for limited current spiking have been suggested.

Work zone variable speed limit systems: Effectiveness and system design issues.

DOT National Transportation Integrated Search

2010-03-01

Variable speed limit (VSL) systems have been used in a number of countries, particularly in Europe, as a method to improve flow and increase safety. VSLs use detectors to collect data on current traffic and/or weather conditions. Posted speed limits ...

Work zone variable speed limit systems : effectiveness and system design issues.

DOT National Transportation Integrated Search

2010-03-01

Variable speed limit (VSL) systems have been used in a number of countries, particularly in Europe, as a method to improve flow and increase safety. VSLs use detectors to collect data on current traffic and/or weather conditions. Posted speed limits ...

Electrochemical reduction of nitrate and nitrite in concentrated sodium hydroxide at platinum and nickel electrodes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hu Lin Li; Robertson, D.H.; Chambers, J.Q.

1996-10-01

This work describes the electrochemical reduction of nitrate in alkaline solutions. Conditions which maximize the current efficiency for the production of dinitrogen and/or ammonia gases could be very important for the treatment of radioactive waste solutions.

System for Anomaly and Failure Detection (SAFD) system development

NASA Technical Reports Server (NTRS)

Oreilly, D.

1992-01-01

This task specified developing the hardware and software necessary to implement the System for Anomaly and Failure Detection (SAFD) algorithm, developed under Technology Test Bed (TTB) Task 21, on the TTB engine stand. This effort involved building two units; one unit to be installed in the Block II Space Shuttle Main Engine (SSME) Hardware Simulation Lab (HSL) at Marshall Space Flight Center (MSFC), and one unit to be installed at the TTB engine stand. Rocketdyne personnel from the HSL performed the task. The SAFD algorithm was developed as an improvement over the current redline system used in the Space Shuttle Main Engine Controller (SSMEC). Simulation tests and execution against previous hot fire tests demonstrated that the SAFD algorithm can detect engine failure as much as tens of seconds before the redline system recognized the failure. Although the current algorithm only operates during steady state conditions (engine not throttling), work is underway to expand the algorithm to work during transient condition.

Cyber-physical system for a water reclamation plant: Balancing aeration, energy, and water quality to maintain process resilience

NASA Astrophysics Data System (ADS)

Zhu, Junjie

Aeration accounts for a large fraction of energy consumption in conventional water reclamation plants (WRPs). Although process operations at older WRPs can satisfy effluent permit requirements, they typically operate with excess aeration. More effective process controls at older WRPs can be challenging as operators work to balance higher energy costs and more stringent effluent limitations while managing fluctuating loads. Therefore, understandings of process resilience or ability to quickly return to original operation conditions at a WRP are important. A state-of-art WRP should maintain process resilience to deal with different kinds of perturbations even after optimization of energy demands. This work was to evaluate the applicability and feasibility of cyber-physical system (CPS) for improving operation at Metropolitan Water Reclamation District of Greater Chicago (MWRDGC) Calumet WRP. In this work, a process model was developed and used to better understand the conditions of current Calumet WRP, with additional valuable information from two dissolved oxygen field measurements. Meanwhile, a classification system was developed to reveal the pattern of historical influent scenario based on cluster analysis and cross-tabulation analysis. Based on the results from the classification, typical process control options were investigated. To ensure the feasibility of information acquisition, the reliability and flexibility of soft sensors were assessed to typical influent conditions. Finally, the process resilience was investigated to better balance influent perturbations, energy demands, and effluent quality for long-term operations. These investigations and evaluations show that although the energy demands change as the influent conditions and process controls. In general, aeration savings could be up to 50% from the level of current consumption; with a more complex process controls, the saving could be up to 70% in relatively steady-state conditions and at least 40% in relatively challenging transient conditions. The soft sensors can provide reliable and flexible performance on target predictions. The plant can still maintain at a similar level of process resilience after 50% aeration saving, even during long-term perturbations. Overall, this work shows that it is well feasible to provide more cost-effective operations at the Calumet WRP, and meanwhile influent perturbations, effluent quality, and process resilience are well in balance.

A Study on Management of Contract Conditions of Yen Loan Projects in Philippine and Vietnam

NASA Astrophysics Data System (ADS)

Matsuba, Yasutaka; Ozawa, Kazumasa; Yasutani, Satoru

FIDIC conditions of contract are used in many cases as general conditions for public works funded by Japanese yen loan, but there are cases where the particular conditions are written as to add some special clauses or change some clauses of FIDIC general conditions based on their own current contract conditions and customs, which will lead to restriction of rights and duties of the Engineer and Contractor. This paper focuses on yen loan projects in Philippine and Vietnam, and describes the actual contract management of FIDIC conditions of contract from the viewpoints such as: a) relationship between Client, Contractor and the Engineer b) claim for rights and contract managements. Based on interviews to parties concerned and literature reviews of public works concerned, contractor's rights are granted relatively wider in yen loan projects compared with locally-funded projects. However, it is also observed that the Engineer's rights are restricted by particular conditions, which is written in line with their own public procurement policies of both countries. Some discussions are added how these local procurement policies affect the implementation of FIDIC conditions of contract, and clarified what are the differences of contract management between both countries.

Excess surface area in bioelectrochemical systems causes ion transport limitations.

PubMed

Harrington, Timothy D; Babauta, Jerome T; Davenport, Emily K; Renslow, Ryan S; Beyenal, Haluk

2015-05-01

We investigated ion transport limitations on 3D graphite felt electrodes by growing Geobacter sulfurreducens biofilms with advection to eliminate external mass transfer limitations. We characterized ion transport limitations by: (i) showing that serially increasing NaCl concentration up to 200 mM increased current linearly up to a total of +273% vs. 0 mM NaCl under advective conditions; (ii) growing the biofilm with a starting concentration of 200 mM NaCl, which led to a maximum current increase of 400% vs. current generation without NaCl, and (iii) showing that un-colonized surface area remained even after steady-state current was reached. After accounting for iR effects, we confirmed that the excess surface area existed despite a non-zero overpotential. The fact that the biofilm was constrained from colonizing and producing further current under these conditions confirmed the biofilms under study here were ion transport-limited. Our work demonstrates that the use of high surface area electrodes may not increase current density when the system design allows ion transport limitations to become dominant. © 2014 Wiley Periodicals, Inc.

Performance Improvements to the Naval Postgraduate School Turbopropulsion Labs Transonic Axially Splittered Rotor

DTIC Science & Technology

2013-12-01

Implementation of current NPS TPL design procedure that uses COTS software (MATLAB, SolidWorks, and ANSYS - CFX ) for the geometric rendering and...procedure that uses commercial-off-the-shelf software (MATLAB, SolidWorks, and ANSYS - CFX ) for the geometric rendering and analysis was modified and... CFX The CFD simulation program in ANSYS Workbench. CFX -Pre CFX boundary conditions and solver settings module. CFX -Solver CFX solver program. CFX

[Study of allergic morbidity in children of female workers from various fields of national economy].

PubMed

Khakimova, R F; Dautov, F F; Iusupova, N Z

2007-01-01

To study the factors contributing to the development of allergic disease in children has recently become of current importance. To determine the indirect influence of maternal working environmental factors on allergic morbidity in children, the authors have examined the working conditions and morbidity of female workers engaged in that or that field of national economy and the health status and allergic diseases in children. The variance analysis was made. The proposed guidelines allow one to study the indirect influence of working environmental factors on allergic morbidity in children.

Graded recombination layers for multijunction photovoltaics.

PubMed

Koleilat, Ghada I; Wang, Xihua; Sargent, Edward H

2012-06-13

Multijunction devices consist of a stack of semiconductor junctions having bandgaps tuned across a broad spectrum. In solar cells this concept is used to increase the efficiency of photovoltaic harvesting, while light emitters and detectors use it to achieve multicolor and spectrally tunable behavior. In series-connected current-matched multijunction devices, the recombination layers must allow the hole current from one cell to recombine, with high efficiency and low voltage loss, with the electron current from the next cell. We recently reported a tandem solar cell in which the recombination layer was implemented using a progression of n-type oxides whose doping densities and work functions serve to connect, with negligible resistive loss at solar current densities, the constituent cells. Here we present the generalized conditions for design of efficient graded recombination layer solar devices. We report the number of interlayers and the requirements on work function and doping of each interlayer, to bridge an work function difference as high as 1.6 eV. We also find solutions that minimize the doping required of the interlayers in order to minimize optical absorption due to free carriers in the graded recombination layer (GRL). We demonstrate a family of new GRL designs experimentally and highlight the benefits of the progression of dopings and work functions in the interlayers.

Thermal diode utilizing asymmetric contacts to heat baths.

PubMed

Komatsu, Teruhisa S; Ito, Nobuyasu

2010-01-01

We propose a simple thermal diode passively acting as a rectifier of heat current. The key design of the diode is the size asymmetry of the areas in contact with two distinct heat baths. The heat-conducting medium is liquid, inside of which gaslike regions are induced depending on the applied conditions. Simulating nanoscale systems of this diode, the rectification of heat current is demonstrated. If the packing density of the medium and the working regime of temperature are properly chosen, the heat current is effectively cut off when the heat bath with narrow contact is hotter, but it flows normally under opposite temperature conditions. In the former case, the gaslike region is induced in the system and it acts as a thermal insulator because it covers the entire narrow area of contact with the bath.

Reconstruction of thin fluorophore-filled capillaries in thick scattering medium using fluorescence diffuse optical tomography within the diffusion approximation

NASA Astrophysics Data System (ADS)

Desrochers, Johanne; Vermette, Patrick; Fontaine, Réjean; Bérubé-Lauzière, Yves

2009-02-01

Current efforts in tissue engineering target the growth of 3D volumes of tissue cultures in bioreactor conditions. Fluorescence optical tomography has the potential to monitor cells viability and tissue growth non-destructively directly within the bioreactor via bio-molecular fluorescent labelling strategies. We currently work on developing the imaging instrumentation for tissue cultures in bioreactor conditions. Previously, we localized in 3D thin fluorescent-labelled capillaries in a cylindrically shaped bioreactor phantom containing a diffusive medium with our time-of-flight localization technique. Here, we present our first reconstruction results of the spatial distribution of fluorophore concentrations for labelled capillaries embedded in a bioreactor phantom.

OTVE turbopump condition monitoring, task E.5

NASA Technical Reports Server (NTRS)

Coleman, Paul T.; Collins, J. J.

1989-01-01

Recent work has been carried out on development of isotope wear analysis and optical and eddy current technologies to provide bearing wear measurements and real time monitoring of shaft speed, shaft axial displacement and shaft orbit of the Orbit Transfer Vehicle hydrostatic bearing tester. Results show shaft axial displacement can be optically measured (at the same time as shaft orbital motion and speed) to within 0.3 mils by two fiberoptic deflectometers. Evaluation of eddy current probes showed that, in addition to measuring shaft orbital motion, they can be used to measure shaft speed without having to machine grooves on the shaft surface as is the usual practice for turbomachinery. The interim results of this condition monitoring effort are presented.

Workplace characteristics and work disability onset for men and women.

PubMed

Crimmins, Eileen M; Hayward, Mark D

2004-01-01

This paper investigates the association between job characteristics and work disability among men and women in older working ages in the United States. We examine whether the association persists when controlling for major chronic disease experience. We also address whether job characteristics are ultimately associated with the receipt of disability benefits. Data are from the Health and Retirement Survey and are nationally representative of noninstitutionalized persons 51-61 in 1992. Disability onset is estimated using a hazard modeling approach for those working at wave 1 (N = 5,999). A logistic regression analysis of disability benefits is based on a risk set of 525 persons who become work-disabled before the second interview. Women's disability onset and health problems appear less related to job characteristics than men's. For men, work disability is associated with stressful jobs, lack of job control, and environmentally hazardous conditions but is not associated with physical demands. Participation in disability benefit programs among those with work disability is unrelated to most job characteristics or health conditions. Understanding of the differing process to work disability for men and women and the relationship between work and health by gender is important for current policy development.

Mitochondrial DNA disease—molecular insights and potential routes to a cure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Russell, Oliver; Turnbull, Doug, E-mail: doug.turnbull@newcastle.ac.uk

2014-07-01

Mitochondrial DNA diseases are common neurological conditions caused by mutations in the mitochondrial genome or nuclear genes responsible for its maintenance. Current treatments for these disorders are focussed on the management of the symptoms, rather than the correction of biochemical defects caused by the mutation. This review focuses on the molecular effects of mutations, the symptoms they cause and current work focusing on the development of targeted treatments for mitochondrial DNA disease. - Highlights: • We discuss several common disease causing mtDNA mutations. • We highlight recent work linking pathogenicity to deletion size and heteroplasmy. • We discuss recent advancesmore » in the development of targeted mtDNA disease treatments.« less

Modelling of thermal stresses in bearing steel structure generated by electrical current impulses

NASA Astrophysics Data System (ADS)

Birjukovs, M.; Jakovics, A.; Holweger, W.

2018-05-01

This work is the study of one particular candidate for white etching crack (WEC) initiation mechanism in wind turbine gearbox bearings: discharge current impulses flowing through bearing steel with associated thermal stresses and material fatigue. Using data/results from previously published works, the authors develop a series of models that are utilized to simulate these processes under various conditions/local microstructure configurations, as well as to verify the results of the previous numerical studies. Presented models show that the resulting stresses are several orders of magnitude below the fatigue limit/yield strength for the parameters used herein. Results and analysis of models provided by Scepanskis, M. et al. also indicate that certain effects predicted in their previous work resulted from a physically unfounded assumption about material thermodynamic properties and numerical model implementation issues.

The Bulgarian Academic Profession in Transition.

ERIC Educational Resources Information Center

Slantcheva, Snejana

2003-01-01

Analyzes the current status of the academic profession in Bulgaria at a time of difficult socioeconomic transition. After providing a brief overview of the historical development of Bulgarian academia, discusses faculty working conditions, the career path within the profession, and the legal framework for the professoriate. Highlights future key…

[Stress and job satisfaction in the discipline of inpatient anesthesiology : results of a web-based survey].

PubMed

Bauer, J; Groneberg, D A

2014-01-01

How do physicians in the specialty of anesthesiology perceive the working conditions regarding stress and job satisfaction? The health system in Germany has been confronted with a rapidly changing framework over the last 20 years: For example, an increased influence of economic patterns on the workflow and the medical decision of physicians has been established forcing them to always take the economic aspects into account. Moreover, a new generation (generation Y) of physicians with other requirements of the work place, meaning mainly a demand for a better work-life balance, has gained a foothold in hospitals. These changes make it very important to investigate the status quo of current working conditions. Working conditions in hospitals in the specialty of anesthesiology is the main issue investigated in this study. For this study 1,321 completed online-questionnaires from physicians in hospitals with the specialty of anesthesiology were analyzed. The questionnaire was based on the stress theory, the effort-reward-imbalance model (ERI) and the job-demand-control model (JDC).The items used in the questionnaire were taken from the ERI questionnaire and the short questionnaire on work analysis (KFZA). By calculating a certain ratio of several items (according to the stress theory), the prevalence of distress could be measured. In addition the overall job satisfaction in the field of anesthesiology was measured and analyzed. In this study 47.0 % (95 %-CI: 44.3-49.7 %) of all respondents showed signs of distress. Simultaneously, 61.8 % (95 %-CI: 59.2-64.5 %) were very satisfied with the job situation. Regarding gender, female physicians perceived a lower control of the work situation whereas male physicians perceived a much higher decision level. This led to a higher prevalence of distress in the group of female physicians regarding the JDC model (odds ratio, OR: 1.54, 95 %-CI: 1.19-2.01). Regarding age, the prevalence of distress increased from 36.5 % in the respondents under 35 years old to 50.7 % in those 35-59 years old (OR: 1.79, 95 %-CI: 1.38-2.32). Looking at the different functional positions in the hospital, senior doctors showed a much higher prevalence of distress (52.8 %) than junior doctors (OR: 1.57, 95 %-CI: 1.21-2.05). Analyzing job satisfaction with respect to the functional position, the highest significant proportion was shown by senior doctors (65.8 %). This study revealed a high prevalence of unfavorable working conditions for anesthetists in hospitals. Taking the forthcoming shortage of qualified physicians in German hospitals into account, these results have to be considered as a cause for concern. Constant unfavorable working conditions have a negative effect on the mental and physical health of employees. Sooner or later a migration of qualified physicians abroad could be the consequence. To prevent a future shortage of qualified physicians and to make the hospital work place more appealing, working conditions have to be adapted to current needs and expectations of employees. The focus should be put on balanced working conditions according to stress models shown in this study.

[Future psychotherapists? Vocational plans and motivation for choosing psychotherapy as a career in german psychology students].

PubMed

Glaesmer, Heide; Spangenberg, Lena; Sonntag, Astrid; Brähler, Elmar; Strauss, Bernhard

2010-12-01

in Germany psychology students can be seen as the major personal resource in psychotherapy. Nevertheless there are few studies on their vocational plans and their interest in psychotherapeutic training. 480 psychology students completed a self-developed questionnaire on their career expectations. 90% of respondents report interest in clinical work and psychotherapeutic training. Most frequently they mention improving therapeutic competencies and career options as pros and current training requirements as cons. Their theoretical orientation (38% behaviour therapy, 19% psychodynamic therapy) is associated with their psychotherapeutic knowledge, study conditions and respondent's characteristics. psychology students consider working and training conditions for psychologists and psychotherapists, when thinking about their future career.

Temperature dependent charge transport in poly(3-hexylthiophene) diodes

NASA Astrophysics Data System (ADS)

Rahaman, Abdulla Bin; Sarkar, Atri; Banerjee, Debamalya

2018-04-01

In this work, we present charge transport properties of poly(3-hexylthiophene) (P3HT) diodes under dark conditions. Temperature dependent current-voltage (J-V) characteristics shows that charge transport represents a transition from ohomic to trap limited current. The forward current density obeys a power law J˜Vm, m>2 represents the space charge limited current region in presence of traps within the band gap. Frequency dependent conductivity has been studied in a temperature range 150K-473K. The dc conductivity values show Arrhenius like behavior and it gives conductivity activation energy 223 meV. Temperature dependent conductivity indicates a thermodynamic transition of our system.

Toward Improved Predictions of Slender Airframe Aerodynamics Using the F-16XL Aircraft

NASA Technical Reports Server (NTRS)

Luckring, James M.; Rizzi, Arthur; Davis, M. Bruce

2016-01-01

A coordinated project has been underway to improve computational fluid dynamics predictions of slender airframe aerodynamics. The work is focused on two flow conditions and leverages a unique flight data set obtained with an F-16XL aircraft. These conditions, a low-speed high angle-of-attack case and a transonic low angle-of-attack case, were selected from a prior prediction campaign wherein the computational fluid dynamics failed to provide acceptable results. In this paper, the background, objectives, and approach to the current project are presented. The work embodies predictions from multiple numerical formulations that are contributed from multiple organizations, and the context of this campaign to other multicode, multi-organizational efforts is included. The relevance of this body of work toward future supersonic commercial transport concepts is also briefly addressed.

Profile of female sex workers in a Chinese county: does it differ by where they came from and where they work?

PubMed

Fang, Xiaoyi; Li, Xiaoming; Yang, Hongmei; Hong, Yan; Zhao, Ran; Dong, Baiqing; Liu, Wei; Zhou, Yuejiao; Liang, Shaoling; Stanton, Bonita

2007-01-01

Since the 1980s, informal or clandestine sex work in the service or entertainment industry has spread from municipalities to small towns in most areas of China. Despite recognition of the important role of female sex workers in HIV and STD epidemics in China, limited data are available regarding their individual characteristics and the social and environmental context of their work. Furthermore, most existing studies on commercial sex in China have been conducted in large cities or tourist attractions. Using data from 454 female sex workers in a rural Chinese county, the current study was designed to explore the individual profiles of commercial sex workers and to examine whether the profile and sexual risk behaviour differ by where the female sex workers came from and where they work. The sample in the current study was different from previous studies in a number of key individual characteristics. However, similarly to previous studies, the subjects in the current study were driven into commercial sex by poverty or limited employment opportunities, lived a stressful life, were subject to sexual harassment and related violence, and engaged in a number of health-compromising behaviours including behaviours that put them at risk of HIV/STD infection and depression. The findings of the current study underscore the urgent need for effective HIV/STD prevention, intervention and mental health promotion programs among female sex workers in China. The data in the current study suggest a strong association of individual profile with the economic conditions of work sites and residence status (in-province residency vs. out-of-province residency), which suggests that such efforts must take the social and cultural contextual factors of working environment (and sexual risks) into consideration.

Profile of female sex workers in a Chinese county: Does it differ by where they came from and where they work?

PubMed Central

Fang, Xiaoyi; Li, Xiaoming; Yang, Hongmei; Hong, Yan; Zhao, Ran; Dong, Baiqing; Liu, Wei; Zhou, Yuejiao; Liang, Shaoling; Stanton, Bonita

2007-01-01

Since the 1980s, informal or clandestine sex work in the service or entertainment industry has spread from municipalities to small towns in most areas of China. Despite recognition of the important role of female sex workers in HIV and STD epidemics in China, limited data are available regarding their individual characteristics and social and environmental context of their work. Furthermore, most existing studies on commercial sex in China have been conducted in large cities or tourist attractions. Using data from 454 female sex workers in a rural Chinese county, the current study was designed to explore the individual profile of commercial sex workers and to examine whether the profile and sexual risk behavior differ by where the female sex workers came from and where they work. The sample in the current study was different from previous studies in a number of key individual characteristics. However, similar to previous studies, the sample in the current study were driven into commercial sex by poverty or limited employment opportunities, lived in a stressful life, were subject to sexual harassment and related violence, and engaged in a number of health-compromising behaviors including behaviors that put them at risk of HIV/STD infection and depression. The findings of the current study underscore the urgent needs for effective HIV/STD prevention intervention and mental health promotion program among female sex workers in China. The data in the current study suggest a strong association of individual profile with the economic conditions of work sites and residence status (in-province residency versus out-province residence) which suggests that such efforts must take the social and cultural contextual factors of their working environment (and sexual risks) into consideration. PMID:18270499

Measuring Plasma Formation Field Strength and Current Loss in Pulsed Power Diodes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnston, Mark D.; Patel, Sonal G.; Falcon, Ross Edward

This LDRD investigated plasma formation, field strength, and current loss in pulsed power diodes. In particular the Self-Magnetic Pinch (SMP) e-beam diode was studied on the RITS-6 accelerator. Magnetic fields of a few Tesla and electric fields of several MV/cm were measured using visible spectroscopy techniques. The magnetic field measurements were then used to determine the current distribution in the diode. This distribution showed that significant beam current extends radially beyond the few millimeter x-ray focal spot diameter. Additionally, shielding of the magnetic field due to dense electrode surface plasmas was observed, quantified, and found to be consistent with themore » calculated Spitzer resistivity. In addition to the work on RITS, measurements were also made on the Z-machine looking to quantify plasmas within the power flow regions. Measurements were taken in the post-hole convolute and final feed gap regions on Z. Dopants were applied to power flow surfaces and measured spectroscopically. These measurements gave species and density/temperature estimates. Preliminary B-field measurements in the load region were attempted as well. Finally, simulation work using the EMPHASIS, electromagnetic particle in cell code, was conducted using the Z MITL conditions. The purpose of these simulations was to investigate several surface plasma generations models under Z conditions for comparison with experimental data.« less

Unveiling factors that contribute to functional aging among health care shiftworkers in São Paulo, Brazil.

PubMed

Fischer, Frida Marina; Bellusci, Silvia M; Teixeira, Liliane R; Borges, Flávio N S; Ferreira, Regiane M; Gonçalves, Mariana B L; Martins, Samantha E; Christoffolete, Marcelo A

2002-01-01

The aims of this study were to evaluate aging factors associated with work stressors, work ability, and the quality of living conditions, among health care personnel. A cross-sectional study was conducted among 176 health care shiftworkers. Two health survey questionnaires (Tuomi et al., 1997, Scandinavian Journal of Work, Environment and Health, 17(Suppl 1), 67-74; and Tepas, 1996, unpublished instrument) were completed and ergonomic work analyses (Rohmert & Landau, 1983, A new technique for job analysis, London and New York: Taylor & Francis) were carried out at the emergency wards. Main concerns about exposure at the workplace were changes in equipment and technology, transportation, and changes in employer policies. Main concerns about off-the-job conditions were personal safety, increases in the cost of living, food safety, and water and air quality. 81.7% scored adequate (> 36.5 points) in the Work Ability Index, and considered themselves having adequate current work ability to cope with physical, mental, and social demands. The most frequently reported diseases were musculoskeletal disorders and minor emotional problems.

Asthma Among Employed Adults, by Industry and Occupation - 21 States, 2013.

PubMed

Dodd, Katelynn E; Mazurek, Jacek M

2016-12-02

Workers in various industries and occupations are at risk for work-related asthma* (1). Data from the 2006-2007 adult Behavioral Risk Factor Surveillance System (BRFSS) Asthma Call-back Survey (ACBS), an in-depth asthma survey conducted with respondents who report an asthma diagnosis, from 33 states indicated that up to 48% of adult current asthma might be related to work and could therefore potentially be prevented (2). Identification of the industries and occupations with increased prevalence of asthma might inform work-related asthma intervention and prevention efforts. To assess the industry-specific and occupation-specific proportions of adults with current asthma by state, CDC analyzed data from the 2013 BRFSS industry and occupation module, collected from 21 states for participants aged ≥18 years who, at the time of the survey interview, were employed or had been out of work for <12 months. Among these respondents, 7.7% had current asthma; based on the Asthma Call-back Survey results, this finding means as many as 2.7 million U.S. workers might have asthma caused by or exacerbated by workplace conditions. State-specific variations in the prevalence of current asthma by industry and occupation were observed. By state, current asthma prevalence was highest among workers in the information industry (18.0%) in Massachusetts and in health care support occupations (21.5%) in Michigan. Analysis of BRFSS industry and occupation and optional asthma modules can be used to identify industries and occupations to assess for asthma among workers, identify workplace exposures, and guide the design and evaluation of effective work-related asthma prevention and education programs (1).

Equity and working time: a challenge to achieve.

PubMed

Fischer, Frida Marina; Rotenberg, Lúcia; de Castro Moreno, Claudia Roberta

2004-01-01

Equity is a humanitarian issue that gained strength during the transition from the 20th to the 21st century due to the mounting global discussion and social crisis involving human rights, health, and work. This article aims at (1) introducing the concept of equity as it applies to work environments, particularly to situations involving demanding work schedules, (2) discussing the role of science in equity issues related to work, (3) introducing a new scientific society dedicated to working-time issues, and (4) presenting an overview of new research on working time and health as addressed by the series of manuscripts published in this special issue of Chronobiology International devoted to the XVIth International Symposium on Night and Shiftwork, held in Santos, Brazil, November 2003. The concept of equity has a political as a well as a scientific dimension. Many worldwide organizations, e.g., civil society, academia, and occupational health research institutions, advocate prompt actions toward equity as a strategy to attain sustainable development and to reduce poverty. The analyses of current tendencies in work settings reveal a general situation of disrespect for equity principles, which is expressed by heavy workloads, long work hours, poor work conditions, and deregulation of established labor laws, mainly in (but not restricted to) developing countries. In spite of the great contribution of science in the past five decades, obstacles stand in the way of effectively improving good working conditions, particularly in times of precarious employment. The Working Time Society is a new scientific society that aims at promoting research into working time and health and offers practical advice on how to minimize adverse effects of working hours on workers' health and well-being. An updated view of the research on working times and health includes studies on the relationship between work schedules, worker health, and well-being; effects of night and shiftwork on the internal synchronization of circadian rhythms and laboratory and field interventions; new methods of investigation or new approaches in shift-work studies; and prediction of risks in night and shift work. Current tendencies of work organization contribute to the amplification of inequality across groups and populations, revealing that equity remains a challenge to achieve.

Extracting black-hole rotational energy: The generalized Penrose process

NASA Astrophysics Data System (ADS)

Lasota, J.-P.; Gourgoulhon, E.; Abramowicz, M.; Tchekhovskoy, A.; Narayan, R.

2014-01-01

In the case involving particles, the necessary and sufficient condition for the Penrose process to extract energy from a rotating black hole is absorption of particles with negative energies and angular momenta. No torque at the black-hole horizon occurs. In this article we consider the case of arbitrary fields or matter described by an unspecified, general energy-momentum tensor Tμν and show that the necessary and sufficient condition for extraction of a black hole's rotational energy is analogous to that in the mechanical Penrose process: absorption of negative energy and negative angular momentum. We also show that a necessary condition for the Penrose process to occur is for the Noether current (the conserved energy-momentum density vector) to be spacelike or past directed (timelike or null) on some part of the horizon. In the particle case, our general criterion for the occurrence of a Penrose process reproduces the standard result. In the case of relativistic jet-producing "magnetically arrested disks," we show that the negative energy and angular-momentum absorption condition is obeyed when the Blandford-Znajek mechanism is at work, and hence the high energy extraction efficiency up to ˜300% found in recent numerical simulations of such accretion flows results from tapping the black hole's rotational energy through the Penrose process. We show how black-hole rotational energy extraction works in this case by describing the Penrose process in terms of the Noether current.

Gender and Ageing at Work in Chile: Employment, Working Conditions, Work-Life Balance and Health of Men and Women in an Ageing Workforce.

PubMed

Vives, Alejandra; Gray, Nora; González, Francisca; Molina, Agustín

2018-04-18

In Chile, working after retirement age has grown substantially over the last years. This, in addition to the country's current discussion about extending retirement age, motivates the need of generating evidence on the occupational health and safety of the working old, with a special focus on women, who are critically disadvantaged in Chile's labour market. The objective of this paper is to describe and compare the ageing workforce of women and men in Chile in terms of labour market participation, employment and working conditions, work-life balance, and health. The social determinants of health and employment sustainability frameworks guide this study. Cross-sectional data from three publicly available sources: the Chilean Labour Force Survey, NENE (2010); the first Chilean Employment and working conditions survey, ENETS (2009-2010) and the second National Health Survey, ENS (2009). Participation rates and employment conditions (NENE and ENETS), working conditions, occupational health and work-life balance (ENETS) and chronic health conditions (ENS) were described by 5-year age groups separately for women and men. Descriptions cover all age groups in order to identify trends and patterns characteristic of older workers. Rates of occupation decrease sharply after age 54 in women and 59 in men. Ageing women and men who continue to work are more likely to be in own-account (self-employed) work than younger workers; in the case of women, in households as domestic workers, and men, in agriculture. Social protection and workplace rights are markedly reduced in older workers. Part-time work increases from the age of 50 onwards, especially among women, but average working hours do not decrease under 30 h a week for either women or men. Interestingly, between ages 60 and 64, there is a peak increase of day and night shift-work among women, which co-occurs with a peak in domestic work, possibly corresponding to women working as caretakers of elderly people. Several workplace risks continue to be high into old age: intensive work and demanding physical work, especially in men, and the combination of paid and unpaid care work in women, which continues to be high up to the age of 70 years. The health of older workers is better than that of non-working people of the same age, a gap which is markedly larger for women than men and tends to increase among women as they age. Results indicate that Chileans working into old age face precarious jobs with limited protection and several adverse working conditions. Noteworthy, women carry the double burden of paid and unpaid work into their late years. In addition, results suggest they are affected more profoundly by the healthy worker effect whereby the health condition determines the probability of finding and keeping a job-also known as a health selection mechanism-which increases as they age. These employment and working conditions indicate that working into old age is not yet sustainable in Chile and counts as evidence that needs to be taken into account in discussions about delaying the retirement age in the country, as well as incorporating support systems to alleviate the double work burden of ageing working women.

Two-Phase Flow in Packed Columns and Generation of Bubbly Suspensions for Chemical Processing in Space

NASA Technical Reports Server (NTRS)

Motil, Brian J.; Green, R. D.; Nahra, H. K.; Sridhar, K. R.

2000-01-01

For long-duration space missions, the life support and In-Situ Resource Utilization (ISRU) systems necessary to lower the mass and volume of consumables carried from Earth will require more sophisticated chemical processing technologies involving gas-liquid two-phase flows. This paper discusses some preliminary two-phase flow work in packed columns and generation of bubbly suspensions, two types of flow systems that can exist in a number of chemical processing devices. The experimental hardware for a co-current flow, packed column operated in two ground-based low gravity facilities (two-second drop tower and KC- 135 low-gravity aircraft) is described. The preliminary results of this experimental work are discussed. The flow regimes observed and the conditions under which these flow regimes occur are compared with the available co-current packed column experimental work performed in normal gravity. For bubbly suspensions, the experimental hardware for generation of uniformly sized bubbles in Couette flow in microgravity conditions is described. Experimental work was performed on a number of bubbler designs, and the capillary bubble tube was found to produce the most consistent size bubbles. Low air flow rates and low Couette flow produce consistent 2-3 mm bubbles, the size of interest for the "Behavior of Rapidly Sheared Bubbly Suspension" flight experiment. Finally the mass transfer implications of these two-phase flows is qualitatively discussed.

Paediatric Palliative Care and Intellectual Disability--A Unique Context

ERIC Educational Resources Information Center

Duc, Jacqueline K.; Herbert, Anthony Robert; Heussler, Helen S.

2017-01-01

Background: Paediatric palliative care is a nuanced area of practice with additional complexities in the context of intellectual disability. There is currently minimal research to guide clinicians working in this challenging area of care. Method: This study describes the complex care of children with life-limiting conditions and intellectual…

Issues of Teaching Metrology in Higher Education Institutions of Civil Engineering in Russia

ERIC Educational Resources Information Center

Pukharenko, Yurii Vladimirovich; Norin, Veniamin Aleksandrovich

2017-01-01

The work analyses the training process condition in teaching the discipline "Metrology, Standardization, Certification and Quality Control." It proves that the current educational standard regarding the instruction of the discipline "Metrology, Standardization, Certification and Quality Control" does not meet the needs of the…

Improving the Efficiency of Dialogue in Tutoring

ERIC Educational Resources Information Center

Kopp, Kristopher J.; Britt, M. Anne; Millis, Keith; Graesser, Arthur C.

2012-01-01

The current studies investigated the efficient use of dialogue in intelligent tutoring systems that use natural language interaction. Such dialogues can be relatively time-consuming. This work addresses the question of how much dialogue is needed to produce significant learning gains. In Experiment 1, a full dialogue condition and a read-only…

Sleepless in Academia

ERIC Educational Resources Information Center

Acker, Sandra; Armenti, Carmen

2004-01-01

The conditions under which women academics work provide the impetus for this article. Current trends in feminist and other writing are moving us away from dwelling on the disadvantages women experience in the academy. Yet the findings from the two Canadian studies reported here suggest that issues around children and career, anxieties about…

Graduate Students' Mental Health: Departmental Contexts as a Source of Differential Risk

ERIC Educational Resources Information Center

La Touche, Rachel A.

2017-01-01

Research in higher education acknowledges academic performance, progress and general health as adversely impacted by mental health challenges. These challenges are consistent with numerous life changes that accompany the student experience, including changes related to work, finances, social interactions and living conditions. Current scholarship…

Somalia: Current Conditions and Prospects for a Lasting Peace

DTIC Science & Technology

2011-04-20

hijacked. In 2009, the Ukrainian-owned ship, MV Faina, which was carrying 33 T-72 tanks and other weapons and a Japanese -owned ship, MV Chemstar, were...characterized as extremist and jihadist. The ICU was accused of shutting down cinemas and prohibiting women from working. Some of these measures were

Somalia: Current Conditions and Prospects for a Lasting Peace

DTIC Science & Technology

2010-12-16

tanks and other weapons and a Japanese -owned ship, MV Chemstar, were released. In February 2010, a Libyan-owned cargo ship, reportedly flying a North... cinemas and prohibiting women from working. Some of these measures were taken by the Courts, although for reasons other than the Courts’ alleged

Somalia: Current Conditions and Prospects for a Lasting Peace

DTIC Science & Technology

2010-02-04

weapons and a Japanese -owned ship, MV Chemstar, were released. The pirates have reportedly earned more than $120 million in ransom payments, and have...shutting down cinemas and prohibiting women from working. Some of these measures were taken by the Courts, although for different reasons and not because

Somalia: Current Conditions and Prospects for a Lasting Peace

DTIC Science & Technology

2010-08-06

Ukrainian-owned ship, MV Faina, which was carrying 33 T-72 tanks and other weapons and a Japanese -owned ship, MV Chemstar, were released. In February...and jihadist. The ICU was accused of shutting down cinemas and prohibiting women from working. Some of these measures were taken by the Courts

Somalia: Current Conditions and Prospects for a Lasting Peace

DTIC Science & Technology

2009-05-21

February 2009, Somali pirates released several ships, including a Japanese -owned ship, MV Chemstar, and the MV Faina. The pirates have reportedly earned...extremist and jihadist. The ICU was accused of shutting down cinemas and prohibiting women from working. Some of these measures were taken by the Courts

The Effects of Levels of Elaboration on Learners' Strategic Processing of Text

ERIC Educational Resources Information Center

Dornisch, Michele; Sperling, Rayne A.; Zeruth, Jill A.

2011-01-01

In the current work, we examined learners' comprehension when engaged with elaborative processing strategies. In Experiment 1, we randomly assigned students to one of five elaborative processing conditions and addressed differences in learners' lower- and higher-order learning outcomes and ability to employ elaborative strategies. Findings…

Effect of Surge Current Testing on Reliability of Solid Tantalum Capacitors

NASA Technical Reports Server (NTRS)

Teverovsky, Alexander

2008-01-01

Tantalum capacitors manufactured per military specifications are established reliability components and have less than 0.001% of failures per 1000 hours for grades D or S, thus positioning these parts among electronic components with the highest reliability characteristics. Still, failures of tantalum capacitors do happen and when it occurs it might have catastrophic consequences for the system. To reduce this risk, further development of a screening and qualification system with special attention to the possible deficiencies in the existing procedures is necessary. The purpose of this work is evaluation of the effect of surge current stress testing on reliability of the parts at both steady-state and multiple surge current stress conditions. In order to reveal possible degradation and precipitate more failures, various part types were tested and stressed in the range of voltage and temperature conditions exceeding the specified limits. A model to estimate the probability of post-surge current testing-screening failures and measures to improve the effectiveness of the screening process has been suggested.

Finite-Element Analysis of Current-Induced Thermal Stress in a Conducting Sphere

NASA Astrophysics Data System (ADS)

Liu, Ming; Yang, Fuqian

2012-02-01

Understanding the electrothermal-mechanical behavior of electronic interconnects is of practical importance in improving the structural reliability of electronic devices. In this work, we use the finite-element method to analyze the Joule-heating-induced thermomechanical deformation of a metallic sphere that is sandwiched between two rigid plates. The deformation behavior of the sphere is elastic-perfectly plastic with Young's modulus and yield stress decreasing with temperature. The mechanical stresses created by Joule heating are found to depend on the thermal and mechanical contact conditions between the sphere and the plates. The temperature rise in the sphere for the diathermal condition between the sphere and the plates deviates from the square relation between Joule heat and electric current, due to the temperature dependence of the electrothermal properties of the material. For large electric currents, the simulations reveal the decrease of von Mises stress near the contact interfaces, which suggests that current-induced structural damage will likely occur near the contact interfaces.

Physicians’ perceptions of capacity building for managing chronic disease in seniors using integrated interprofessional care models

PubMed Central

Lee, Linda; Heckman, George; McKelvie, Robert; Jong, Philip; D’Elia, Teresa; Hillier, Loretta M.

2015-01-01

Abstract Objective To explore the barriers to and facilitators of adapting and expanding a primary care memory clinic model to integrate care of additional complex chronic geriatric conditions (heart failure, falls, chronic obstructive pulmonary disease, and frailty) into care processes with the goal of improving outcomes for seniors. Design Mixed-methods study using quantitative (questionnaires) and qualitative (interviews) methods. Setting Ontario. Participants Family physicians currently working in primary care memory clinic teams and supporting geriatric specialists. Methods Family physicians currently working in memory clinic teams (n = 29) and supporting geriatric specialists (n = 9) were recruited as survey participants. Interviews were conducted with memory clinic lead physicians (n = 16). Statistical analysis was done to assess differences between family physician ratings and geriatric specialist ratings related to the capacity for managing complex chronic geriatric conditions, the role of interprofessional collaboration within primary care, and funding and staffing to support geriatric care. Results from both study methods were compared to identify common findings. Main findings Results indicate overall support for expanding the memory clinic model to integrate care for other complex conditions. However, the current primary care structure is challenged to support optimal management of patients with multiple comorbidities, particularly as related to limited funding and staffing resources. Structured training, interprofessional teams, and an active role of geriatric specialists within primary care were identified as important facilitators. Conclusion The memory clinic model, as applied to other complex chronic geriatric conditions, has the potential to build capacity for high-quality primary care, improve health outcomes, promote efficient use of health care resources, and reduce health care costs. PMID:25932482

Alcohol Use, Working Conditions, Job Benefits, and the Legacy of the “Dop” System among Farm Workers in the Western Cape Province, South Africa: Hope Despite High Levels of Risky Drinking

PubMed Central

Gossage, J. Phillip; Snell, Cudore L.; Parry, Charles D. H.; Marais, Anna-Susan; Barnard, Ronel; de Vries, Marlene; Blankenship, Jason; Seedat, Soraya; Hasken, Julie M.; May, Philip A.

2014-01-01

This study describes alcohol consumption in five Western Cape Province communities. Cross-sectional data from a community household sample (n = 591) describe the alcohol use patterns of adult males and females, and farm workers vs. others. Data reveal that men were more likely to be current drinkers than women, 75.1% vs. 65.8% (p = 0.033); farm laborers were more likely to be current drinkers than individuals in other occupations 83.1% vs. 66.8% (p = 0.004). Group, binge drinking on weekends was the norm; men were more likely to be binge drinkers in the past week than women 59.8% vs. 48.8% (p = 0.086); farm workers were more likely to binge than others 75.0% vs. 47.5% (p < 0.001). The legacy of “Dop” contributes to current risky drinking behaviors. Farm owners or managers were interviewed on 11 farms, they described working conditions on their farms and how the legacy of “Dop” is reflected in the current use of alcohol by their workers. “Dop” was given to farm workers in the past on six of the 11 farms, but was discontinued for different reasons. There is zero tolerance for coming to work intoxicated; farm owners encourage responsible use of alcohol and assist farm workers in getting help for alcohol problems when necessary. The farm owners report some positive initiatives, were ahead of the movement to provide meaningful wages, and provide other important amenities. Further research is needed to assess whether progressive practices on some farms will reduce harmful alcohol use. PMID:25050650

Effect of the cesium and potassium doping of multiwalled carbon nanotubes grown in an electrical arc on their emission characteristics

NASA Astrophysics Data System (ADS)

Izrael'yants, K. R.; Orlov, A. P.; Ormont, A. B.; Chirkova, E. G.

2017-04-01

The effect of cesium and potassium atoms deposited onto multiwalled carbon nanotubes grown in an electrical arc on their emission characteristics was studied. The current-voltage characteristics of the field electron emission of specimens with cesium or potassium doped multiwalled carbon nanotubes of this type were revealed to retain their linear character in the Fowler-Nordheim coordinates within several orders of magnitude of change in the emission current. The deposition of cesium and potassium atoms was shown to lead to a considerable increase in the emission current and a decrease in the work function φ of studied emitters with multiwalled nanotubes. The work function was established to decrease to φ 3.1 eV at an optimal thickness of coating with cesium atoms and to φ 2.9 eV in the case of doping with potassium atoms. Cesium and potassium deposition conditions optimal for the attainment of a maximum emission current were found.

Review article: Staff perception of the emergency department working environment: Integrative review of the literature

PubMed Central

Abraham, Louisa; Greenslade, Jaimi; Thom, Ogilvie; Carlstrom, Eric; Wallis, Marianne; Crilly, Julia

2016-01-01

Abstract Employees in EDs report increasing role overload because of critical staff shortages, budgetary cuts and increased patient numbers and acuity. Such overload could compromise staff satisfaction with their working environment. This integrative review identifies, synthesises and evaluates current research around staff perceptions of the working conditions in EDs. A systematic search of relevant databases, using MeSH descriptors ED/EDs, Emergency room/s, ER/s, or A&E coupled with (and) working environment, working condition/s, staff perception/s, as well as reference chaining was conducted. We identified 31 key studies that were evaluated using the mixed methods assessment tool (MMAT). These comprised 24 quantitative‐descriptive studies, four mixed descriptive/comparative (non‐randomised controlled trial) studies and three qualitative studies. Studies included varied widely in quality with MMAT scores ranging from 0% to 100%. A key finding was that perceptions of working environment varied across clinical staff and study location, but that high levels of autonomy and teamwork offset stress around high pressure and high volume workloads. The large range of tools used to assess staff perception of working environment limits the comparability of the studies. A dearth of intervention studies around enhancing working environments in EDs limits the capacity to recommend evidence‐based interventions to improve staff morale. © 2016 The Authors. Emergency Medicine Australasia published by John Wiley & Sons Australia, Ltd on behalf of Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine PMID:26784282

Arrester Resistive Current Measuring System Based on Heterogeneous Network

NASA Astrophysics Data System (ADS)

Zhang, Yun Hua; Li, Zai Lin; Yuan, Feng; Hou Pan, Feng; Guo, Zhan Nan; Han, Yue

2018-03-01

Metal Oxide Arrester (MOA) suffers from aging and poor insulation due to long-term impulse voltage and environmental impact, and the value and variation tendency of resistive current can reflect the health conditions of MOA. The common wired MOA detection need to use long cables, which is complicated to operate, and that wireless measurement methods are facing the problems of poor data synchronization and instability. Therefore a novel synchronous measurement system of arrester current resistive based on heterogeneous network is proposed, which simplifies the calculation process and improves synchronization, accuracy and stability and of the measuring system. This system combines LoRa wireless network, high speed wireless personal area network and the process layer communication, and realizes the detection of arrester working condition. Field test data shows that the system has the characteristics of high accuracy, strong anti-interference ability and good synchronization, which plays an important role in ensuring the stable operation of the power grid.

Some Aspects of Advanced Tokamak Modeling in DIII-D

NASA Astrophysics Data System (ADS)

St John, H. E.; Petty, C. C.; Murakami, M.; Kinsey, J. E.

2000-10-01

We extend previous work(M. Murakami, et al., General Atomics Report GA-A23310 (1999).) done on time dependent DIII-D advanced tokamak simulations by introducing theoretical confinement models rather than relying on power balance derived transport coefficients. We explore using NBCD and off axis ECCD together with a self-consistent aligned bootstrap current, driven by the internal transport barrier dynamics generated with the GLF23 confinement model, to shape the hollow current profile and to maintain MHD stable conditions. Our theoretical modeling approach uses measured DIII-D initial conditions to start off the simulations in a smooth consistent manner. This mitigates the troublesome long lived perturbations in the ohmic current profile that is normally caused by inconsistent initial data. To achieve this goal our simulation uses a sequence of time dependent eqdsks generated autonomously by the EFIT MHD equilibrium code in analyzing experimental data to supply the history for the simulation.

Muscular and Aerobic Fitness, Working Memory, and Academic Achievement in Children.

PubMed

Kao, Shih-Chun; Westfall, Daniel R; Parks, Andrew C; Pontifex, Matthew B; Hillman, Charles H

2017-03-01

This study investigated the relationship between aerobic and muscular fitness with working memory and academic achievement in preadolescent children. Seventy-nine 9- to 11-yr-old children completed an aerobic fitness assessment using a graded exercise test; a muscular fitness assessment consisting of upper body, lower body, and core exercises; a serial n-back task to assess working memory; and an academic achievement test of mathematics and reading. Hierarchical regression analyses indicated that after controlling for demographic variables (age, sex, grade, IQ, socioeconomic status), aerobic fitness was associated with greater response accuracy and d' in the 2-back condition and increased mathematic performance in algebraic functions. Muscular fitness was associated with increased response accuracy and d', and longer reaction time in the 2-back condition. Further, the associations of muscular fitness with response accuracy and d' in the 2-back condition were independent of aerobic fitness. The current findings suggest the differential relationships between the aerobic and the muscular aspects of physical fitness with working memory and academic achievement. With the majority of research focusing on childhood health benefits of aerobic fitness, this study suggests the importance of muscular fitness to cognitive health during preadolescence.

The effects of maternal working conditions and mastery on child behavior problems: studying the intergenerational transmission of social control.

PubMed

Rogers, S J; Parcel, T L; Menaghan, E G

1991-06-01

We assess the impact of maternal sense of mastery and maternal working conditions on maternal perceptions of children's behavior problems as a means to study the transmission of social control across generations. We use a sample of 521 employed mothers and their four-to six-year-old children from the National Longitudinal Survey's Youth Cohort in 1986. Regarding working conditions, we consider mother's hourly wage, work hours, and job content including involvement with things (vs. people), the requisite level of physical activity, and occupational complexity. We also consider maternal and child background and current family characteristics, including marital status, family size, and home environment. Maternal mastery was related to fewer reported behavior problems among children. Lower involvement with people and higher involvement with things, as well as low physical activity, were related significantly to higher levels of perceived problems. In addition, recent changes in maternal marital status, including maternal marriage or remarriage, increased reports of problems; stronger home environments had the opposite effect. We interpret these findings as suggesting how maternal experiences of control in the workplace and personal resources of control can influence the internalization of control in children.

Mount Rainier National Park

USGS Publications Warehouse

Hoffman, Robert; Woodward, Andrea; Haggerty, Patricia K.; Jenkins, Kurt J.; Griffin, Paul C.; Adams, Michael J.; Hagar, Joan; Cummings, Tonnie; Duriscoe, Dan; Kopper, Karen; Riedel, Jon; Samora, Barbara; Marin, Lelaina; Mauger, Guillaume S.; Bumbaco, Karen; Littell, Jeremy S.

2014-01-01

Natural Resource Condition Assessments (NRCAs) evaluate current conditions for a subset of natural resources and resource indicators in national parks. NRCAs also report on trends in resource condition (when possible), identify critical data gaps, and characterize a general level of confidence for study findings. The resources and indicators emphasized in a given project depend on the park’s resource setting, status of resource stewardship planning and science in identifying high-priority indicators, and availability of data and expertise to assess current conditions for a variety of potential study resources and indicators. Although the primary objective of NRCAs is to report on current conditions relative to logical forms of reference conditions and values, NRCAs also report on trends, when appropriate (i.e., when the underlying data and methods support such reporting), as well as influences on resource conditions. These influences may include past activities or conditions that provide a helpful context for understanding current conditions and present-day threats and stressors that are best interpreted at park, watershed, or landscape scales (though NRCAs do not report on condition status for land areas and natural resources beyond park boundaries). Intensive cause-andeffect analyses of threats and stressors, and development of detailed treatment options, are outside the scope of NRCAs. It is also important to note that NRCAs do not address resources that lack sufficient data for assessment. For Mount Rainier National Park, this includes most invertebrate species and many other animal species that are subject to significant stressors from climate change and other anthropogenic sources such as air pollutants and recreational use. In addition, we did not include an analysis of the physical hydrology associated with streams (such as riverine landforms, erosion and aggradation which is significant in MORA streams), due to a loss of staff expertise from the USGS-BRD staff conducting the work, and human disturbance landcover issues such as the effects of roads, trails, and other anthropogenic developments due to lack of funds.

A partially reflecting random walk on spheres algorithm for electrical impedance tomography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maire, Sylvain, E-mail: maire@univ-tln.fr; Simon, Martin, E-mail: simon@math.uni-mainz.de

2015-12-15

In this work, we develop a probabilistic estimator for the voltage-to-current map arising in electrical impedance tomography. This novel so-called partially reflecting random walk on spheres estimator enables Monte Carlo methods to compute the voltage-to-current map in an embarrassingly parallel manner, which is an important issue with regard to the corresponding inverse problem. Our method uses the well-known random walk on spheres algorithm inside subdomains where the diffusion coefficient is constant and employs replacement techniques motivated by finite difference discretization to deal with both mixed boundary conditions and interface transmission conditions. We analyze the global bias and the variance ofmore » the new estimator both theoretically and experimentally. Subsequently, the variance of the new estimator is considerably reduced via a novel control variate conditional sampling technique which yields a highly efficient hybrid forward solver coupling probabilistic and deterministic algorithms.« less

Creep-Rupture Behavior and Recrystallization in HR6W and Haynes Alloy 230 Cold-Bent Boiler Tubing for Ultrasupercritical (USC) Steam Boiler Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shingledecker, John P

2007-01-01

Creep-rupture experiments were conducted on HR6W and Haynes 230, candidate Ultrasupercritical (USC) alloys, tubes to evaluate the effects of cold-work and recrystallization during high-temperature service. These creep tests were performed by internally pressurizing cold-bent boiler tubes at 775 C for times up to 8000 hours. The bends were fabricated with cold-work levels beyond the current ASME Boiler and Pressure Vessel (ASME B&PV) Code Section I limits for austenitic stainless steels. Destructive metallographic evaluation of the crept tube bends was used to determine the effects of cold-work and the degree of recrystallization. The metallographic analysis combined with an evaluation of themore » creep and rupture data suggest that solid-solution strengthened nickel-based alloys can be fabricated for high-temperature service at USC conditions utilizing levels of cold-work higher than the current allowed levels for austenitic stainless steels.« less

Leader empowering behaviours, staff nurse empowerment and work engagement/burnout.

PubMed

Greco, Paula; Laschinger, Heather K Spence; Wong, Carol

2006-12-01

Efforts to improve nursing working conditions are critical to retaining nurses currently in the system and attracting newcomers to the profession (Laschinger et al. 2003b). The nurse leader's empowering behaviours can be pivotal in the way nurses react to their work environment. The purpose of this study was to test a model examining the relationship between nurse leaders' empowerment behaviours, perceptions of staff empowerment, areas of work life and work engagement using Kanter's theory of structural power in organizations. A cross-sectional correlational survey design tested the model in a random sample of 322 staff nurses in acute care hospitals across Ontario. Overall, staff nurses perceived their leaders' behaviours to be somewhat empowering and their work environment to be moderately empowering. Fifty-three percent reported severe levels of burnout. Leader empowering behaviour had an indirect effect on emotional exhaustion (burnout) through structural empowerment and overall fit in the six areas of work life. The final model statistics revealed a good fit (chi(2)=30.4, chi=3, chi=0.96, chi=0.95, chi=0.95). These findings suggest that the Leader's empowering behaviours can enhance person-job fit and prevent burnout. These findings have important implications in the current nursing shortage.

Working memory capacity in social anxiety disorder: Revisiting prior conclusions.

PubMed

Waechter, Stephanie; Moscovitch, David A; Vidovic, Vanja; Bielak, Tatiana; Rowa, Karen; McCabe, Randi E

2018-04-01

In one of the few studies examining working memory processes in social anxiety disorder (SAD), Amir and Bomyea (2011) recruited participants with and without SAD to complete a working memory span task with neutral and social threat words. Those with SAD showed better working memory performance for social threat words compared to neutral words, suggesting an enhancement in processing efficiency for socially threatening information in SAD. The current study sought to replicate and extend these findings. In this study, 25 participants with a principal diagnosis of SAD, 24 anxious control (AC) participants with anxiety disorders other than SAD, and 27 healthy control (HC) participants with no anxiety disorder completed a working memory task with social threat, general threat, and neutral stimuli. The groups in the current study demonstrated similar working memory performance within each of the word type conditions, thus failing to replicate the principal findings of Amir and Bomyea (2011). Post hoc analyses revealed a significant association between higher levels of anxiety symptomatology and poorer overall WM performance. These results inform our understanding of working memory in the anxiety disorders and support the importance of replication in psychological research. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Attention allocation: Relationships to general working memory or specific language processing.

PubMed

Archibald, Lisa M D; Levee, Tyler; Olino, Thomas

2015-11-01

Attention allocation, updating working memory, and language processing are interdependent cognitive tasks related to the focused direction of limited resources, refreshing and substituting information in the current focus of attention, and receiving/sending verbal communication, respectively. The current study systematically examined the relationship among executive attention, working memory executive skills, and language abilities while adjusting for individual differences in short-term memory. School-age children completed a selective attention task requiring them to recall whether a presented shape was in the same place as a previous target shape shown in an array imposing a low or high working memory load. Results revealed a selective attention cost when working above but not within memory span capacity. Measures of general working memory were positively related to overall task performance, whereas language abilities were related to response time. In particular, higher language skills were associated with faster responses under low load conditions. These findings suggest that attentional control and storage demands have an additive impact on working memory resources but provide only limited evidence for a domain-general mechanism in language learning. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.

A new Method for Determining the Interplanetary Current-Sheet Local Orientation

NASA Astrophysics Data System (ADS)

Blanco, J. J.; Rodríguez-pacheco, J.; Sequeiros, J.

2003-03-01

In this work we have developed a new method for determining the interplanetary current sheet local parameters. The method, called `HYTARO' (from Hyperbolic Tangent Rotation), is based on a modified Harris magnetic field. This method has been applied to a pool of 57 events, all of them recorded during solar minimum conditions. The model performance has been tested by comparing both, its outputs and noise response, with these of the `classic MVM' (from Minimum Variance Method). The results suggest that, despite the fact that in many cases they behave in a similar way, there are specific crossing conditions that produce an erroneous MVM response. Moreover, our method shows a lower noise level sensitivity than that of MVM.

Operational seasonal and interannual predictions of ocean conditions

NASA Technical Reports Server (NTRS)

Leetmaa, Ants

1992-01-01

Dr. Leetmaa described current work at the U.S. National Meteorological Center (NMC) on coupled systems leading to a seasonal prediction system. He described the way in which ocean thermal data is quality controlled and used in a four dimensional data assimilation system. This consists of a statistical interpolation scheme, a primitive equation ocean general circulation model, and the atmospheric fluxes that are required to force this. This whole process generated dynamically consist thermohaline and velocity fields for the ocean. Currently routine weekly analyses are performed for the Atlantic and Pacific oceans. These analyses are used for ocean climate diagnostics and as initial conditions for coupled forecast models. Specific examples of output products were shown both in the Pacific and the Atlantic Ocean.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hasanah, Lilik, E-mail: lilikhasanah@upi.edu; Suhendi, Endi; Tayubi, Yuyu Rahmat

In this work we discuss the surface roughness of Si interface impact to the tunneling current of the Si/Si{sub 1-x}Ge{sub x}/Si heterojunction bipolar transistor. The Si interface surface roughness can be analyzed from electrical characteristics through the transversal electron velocity obtained as fitting parameter factor. The results showed that surface roughness increase as Ge content of virtual substrate increase This model can be used to investigate the effect of Ge content of the virtual substrate to the interface surface condition through current-voltage characteristic.

The changing patterns of psychosocial exposures at work in the south of Europe: Spain as a labor market laboratory.

PubMed

Utzet, Mireia; Moncada, Salvador; Molinero, Emilia; Llorens, Clara; Moreno, Neus; Navarro, Albert

2014-09-01

To examine the pattern of psychosocial risk exposures at work among wage-earners in Spain in 2005 and 2010, and to analyze changes in exposure inequalities by gender and job category. Psychosocial exposures were compared using the COPSOQ-ISTAS21 method, based on two surveys representative of the Spanish wage-earning population (2005 and 2010). Statistical analysis was conducted using correspondence analysis. There was an increase in exposure to high Double Presence, low Social Support, high Work Pace, and high Insecurity about finding a job; and reduction in exposure to high Insecurity about losing a job, and to high Insecurity over worsening of employment conditions. A gender- and occupation-related gradient was maintained. Although this study analyzes wage-earner "survivors" after the outbreak of the current economic crisis, it shows a worsening of harmful exposures to some psychosocial risks. In a context of job destruction, concerns about worsening working conditions appear to be subordinate to insecurity about job loss. © 2014 Wiley Periodicals, Inc.

The Role of Grain Boundary Energy on Grain Boundary Complexion Transitions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bojarski, Stephanie A.; Rohrer, Gregory S.

Grain boundary complexions are distinct equilibrium structures and compositions of a grain boundary and complexion transformations are transition from a metastable to an equilibrium complexion at a specific thermodynamic and geometric conditions. Previous work indicates that, in the case of doped alumina, a complexion transition that increased the mobility of transformed boundaries and resulted in abnormal grain growth also caused a decrease in the mean relative grain boundary energy as well as an increase in the anisotropy of the grain boundary character distribution (GBCD). The current work will investigate the hypothesis that the rates of complexion transitions that result inmore » abnormal grain growth (AGG) depend on grain boundary character and energy. Furthermore, the current work expands upon this understanding and tests the hypothesis that it is possible to control when and where a complexion transition occurs by controlling the local grain boundary energy distribution.« less

Excessive work and risk of haemorrhagic stroke: a nationwide case-control study.

PubMed

Kim, Beom Joon; Lee, Seung-Hoon; Ryu, Wi-Sun; Kim, Chi Kyung; Chung, Jong-Won; Kim, Dohoung; Park, Hong-Kyun; Bae, Hee-Joon; Park, Byung-Joo; Yoon, Byung-Woo

2013-10-01

Adverse effect of excessive work on health has been suggested previously, but it was not documented in cerebrovascular diseases. The authors investigated whether excessive working conditions would associate with increased risk of haemorrhagic stroke. A nationwide matched case-control study database, which contains 940 cases of incident haemorrhagic stroke (498 intracerebral haemorrhages and 442 sub-arachnoid haemorrhages) with 1880 gender- and age- (± 5-year) matched controls, was analysed. Work-related information based on the regular job situation, including type of occupation, regular working time, duration of strenuous activity during regular work and shift work, was gathered through face-to-face interviews. Conditional logistic regression analyses were used for the multivariable analyses. Compared with white-collar workers, blue-collar workers had a higher risk for haemorrhagic stroke (odds ratio, 1.33 [95% confidence interval, 1.06-1.66]). Longer regular working time was associated with increased risk of haemorrhagic stroke [odds ratio, 1.38 (95% confidence interval, 1.05-1.81) for 8-12 h/day; odds ratio, 1.95 (95% confidence interval, 1.33-2.86) for ≥ 13 h/day; compared with ≤ 4 h/day]. Exposure to ≥ 8 h/week of strenuous activity also associated haemorrhagic stroke risk [odds ratio, 1.61 (95% confidence interval, 1.26-2.05); compared with no strenuous activity]. Shift work was not associated with haemorrhagic stroke (P = 0.98). Positive associations between working condition indices and haemorrhagic stroke risk were consistent regardless of haemorrhagic stroke sub-types and current employment status. Blue-collar occupation, longer regular working time and extended duration of strenuous activity during work may relate to an increased risk of haemorrhagic stroke. © 2012 The Authors. International Journal of Stroke © 2012 World Stroke Organization.

Auditory Information Systems in Military Aircraft: Current Configurations Versus the State of the Art.

DTIC Science & Technology

1984-06-01

types of conditions, discriminable differences in intensity, pitch, or use of beats or harmonics shall be provided. If absolute discrimination is...shall be directed to the operator’s headset as well as to the work area. Binaural headsets should not be used in any operational environment below 85...signals are to be used to alert an operator to different types of conditions, discriminable difference in Intensity, pitch, or use of beats and harmonics

Multiple feedback control apparatus for power conditioning equipment

NASA Technical Reports Server (NTRS)

Biess, John (Inventor); Yu, Yuan (Inventor)

1977-01-01

An improved feedback control system to govern the cyclic operation of the power switch of a non-dissipative power conditioning equipment. The apparatus includes two or three control loops working in unison. The first causes the output DC level to be compared with a reference, and the error amplified for control purposes. The second utilizes the AC component of the voltage across the output filter inductor or the current through the output filter capacitor, and the third loop senses the output transients.

Evaluation of Winter Operational Runway Friction Measurement Equipment, Procedures, and Research

NASA Technical Reports Server (NTRS)

1995-01-01

This document produced by the FAA/Industry Winter Runway Friction Measurement and Reporting Working Group, is designed to provide an overview of current information on the present guidance, practices, and procedures for reporting runway pavement surface conditions during winter operations at airports. It contains recommendations on the desirability of providing the best procedural consistency and standardization and discusses the available means to implement the guidance that will result in improved aviation safety at airports during hazardous winter conditions.

Influence of collector heat capacity and internal conditions of heat exchanger on cool-down process of small gas liquefier

NASA Astrophysics Data System (ADS)

Saberimoghaddam, Ali; Bahri Rasht Abadi, Mohammad Mahdi

2018-01-01

Joule-Thomson cooling systems are commonly used in gas liquefaction. In small gas liquefiers, transient cool-down time is high. Selecting suitable conditions for cooling down process leads to decrease in time and cost. In the present work, transient thermal behavior of Joule-Thomson cooling system including counter current helically coiled tube in tube heat exchanger, expansion valve, and collector was studied using experimental tests and simulations. The experiments were performed using small gas liquefier and nitrogen gas as working fluid. The heat exchanger was thermally studied by experimental data obtained from a small gas liquefier. In addition, the simulations were performed using experimental data as variable boundary conditions. A comparison was done between presented and conventional methods. The effect of collector heat capacity and convection heat transfer coefficient inside the tubes on system performance was studied using temperature profiles along the heat exchanger.

Employment of persons with spinal cord lesions injured more than 20 years ago.

PubMed

Lidal, Ingeborg Beate; Hjeltnes, Nils; Røislien, Jo; Stanghelle, Johan Kvalvik; Biering-Sørensen, Fin

2009-01-01

The primary objective was to study factors influencing post-injury employment and withdrawal from work in persons who sustained traumatic spinal cord injury (SCI) more than 20 years ago. A secondary objective was to study life satisfaction in the same patients. A cross-sectional study with retrospective data of 165 SCI-patients admitted to Sunnaas Rehabilitation Hospital 1961-1982. Multiple logistic regression was used to identify predictors for obtaining work post-injury. A Cox proportional hazards regression model was used to study factors influencing early withdrawal from work, i.e. time from injury until discontinuing employment. Sixty-five percent of the participants were employed at some point after the injury. Thirty-five percent still had work at the time of the survey. The odds of obtaining work after injury were higher in persons of younger age at injury, higher in males versus females, higher for persons with paraplegia versus tetraplegia, and for persons classified as Frankel D-E compared to a more severe SCI. Factors associated with shorter time from injury until discontinuing employment were higher age at injury, incidence of injury after 1975 versus before, and a history of pre-injury medical condition(s). Life satisfaction was better for currently employed participants. The study indicates a low employment-rate in persons with SCI, even several years after injury. From the results, we suggest more support, especially to persons of older age at injury and/or with a history of pre-injury medical condition(s), to help them to obtain work and sustain employed for more years after injury.

An R package for simulating growth and organic wastage in aquaculture farms in response to environmental conditions and husbandry practices

PubMed Central

Baldan, Damiano; Porporato, Erika Maria Diletta; Pastres, Roberto

2018-01-01

A new R software package, RAC, is presented. RAC allows to simulate the rearing cycle of 4 species, finfish and shellfish, highly important in terms of production in the Mediterranean Sea. The package works both at the scale of the individual and of the farmed population. Mathematical models included in RAC were all validated in previous works, and account for growth and metabolism, based on input data characterizing the forcing functions—water temperature, and food quality/quantity. The package provides a demo dataset of forcings for each species, as well as a typical set of husbandry parameters for Mediterranean conditions. The present work illustrates RAC main features, and its current capabilities/limitations. Three test cases are presented as a proof of concept of RAC applicability, and to demonstrate its potential for integrating different open products nowadays provided by remote sensing and operational oceanography. PMID:29723208

Relationships of working conditions, health problems and vehicle accidents in bus rapid transit (BRT) drivers.

PubMed

Gómez-Ortiz, Viviola; Cendales, Boris; Useche, Sergio; Bocarejo, Juan P

2018-04-01

The aim of this study was to estimate accident risk rates and mental health of bus rapid transit (BRT) drivers based on psychosocial risk factors at work leading to increased stress and health problems. A cross-sectional research design utilized a self-report questionnaire completed by 524 BRT drivers. Some working conditions of BRT drivers (lack of social support from supervisors and perceived potential for risk) may partially explain Bogota's BRT drivers' involvement in road accidents. Drivers' mental health problems were associated with higher job strain, less support from co-workers, fewer rewards and greater signal conflict while driving. To prevent bus accidents, supervisory support may need to be increased. To prevent mental health problems, other interventions may be needed such as reducing demands, increasing job control, reducing amount of incoming information, simplifying current signals, making signals less contradictory, and revising rewards. © 2018 Wiley Periodicals, Inc.

Field emission study of carbon nanostructures

NASA Astrophysics Data System (ADS)

Zhao, Xin

Recently, carbon nanosheets (CNS), a novel nanostructure, were developed in our laboratory as a field emission source for high emission current. To characterize, understand and improve the field emission properties of CNS, a ultra-high vacuum surface analysis system was customized to conduct relevant experimental research in four distinct areas. The system includes Auger electron spectroscopy (AES), field emission energy spectroscopy (FEES), field emission I-V testing, and thermal desorption spectroscopy (TDS). Firstly, commercial Mo single tips were studied to calibrate the customized system. AES and FEES experiments indicate that a pyramidal nanotip of Ca and O elements formed on the Mo tip surface by field induced surface diffusion. Secondly, field emission I-V testing on CNS indicates that the field emission properties of pristine nanosheets are impacted by adsorbates. For instance, in pristine samples, field emission sources can be built up instantaneously and be characterized by prominent noise levels and significant current variations. However, when CNS are processed via conditioning (run at high current), their emission properties are greatly improved and stabilized. Furthermore, only H2 desorbed from the conditioned CNS, which indicates that only H adsorbates affect emission. Thirdly, the TDS study on nanosheets revealed that the predominant locations of H residing in CNS are sp2 hybridized C on surface and bulk. Fourthly, a fabricating process was developed to coat low work function ZrC on nanosheets for field emission enhancement. The carbide triple-peak in the AES spectra indicated that Zr carbide formed, but oxygen was not completely removed. The Zr(CxOy) coating was dispersed as nanobeads on the CNS surface. Although the work function was reduced, the coated CNS emission properties were not improved due to an increased beta factor. Further analysis suggest that for low emission current (<1 uA), the H adsorbates affect emission by altering the work function. In high emission current (>10 uA), thermal, ionic or electronic transition effects may occur, which differently affect the field emission process.

Effect of Wind Flow on Convective Heat Losses from Scheffler Solar Concentrator Receivers

NASA Astrophysics Data System (ADS)

Nene, Anita Arvind; Ramachandran, S.; Suyambazhahan, S.

2018-05-01

Receiver is an important element of solar concentrator system. In a Scheffler concentrator, solar rays get concentrated at focus of parabolic dish. While radiation losses are more predictable and calculable since strongly related to receiver temperature, convective looses are difficult to estimate in view of additional factors such as wind flow direction, speed, receiver geometry, prior to current work. Experimental investigation was carried out on two geometries of receiver namely cylindrical and conical with 2.7 m2 Scheffler to find optimum condition of tilt to provide best efficiency. Experimental results showed that as compared to cylindrical receiver, conical receiver gave maximum efficiency at 45° tilt angle. However effect of additional factors like wind speed, wind direction on especially convective losses could not be separately seen. The current work was undertaken to investigate further the same two geometries using computation fluid dynamics using FLUENT to compute convective losses considering all variables such at tilt angle of receiver, wind velocity and wind direction. For cylindrical receiver, directional heat transfer coefficient (HTC) is remarkably high to tilt condition meaning this geometry is critical to tilt leading to higher convective heat losses. For conical receiver, directional average HTC is remarkably less to tilt condition leading to lower convective heat loss.

Design Support System for Open Distance Learning Student Teamwork

NASA Astrophysics Data System (ADS)

Putranto, A.; Pradipto, Y. D.

2017-01-01

Open distance learning students in doing team assignment, they seldom face to some problems such as student fell unfair in numbers of workload contribution, instructors also do not know which students do more work than others. So there are some questions ie: how to connect between instructor, team members, and working documents. Methods will be used are first, analyzing current condition and last by designing systems to connect between instructor, team members, and document. The expected result is support systems for open distance learning student teamwork.

A comparison of licensed and un-licensed artisanal and small-scale gold miners (ASGM) in terms of socio-demographics, work profiles, and injury rates.

PubMed

Calys-Tagoe, Benedict N L; Clarke, Edith; Robins, Thomas; Basu, Niladri

2017-11-06

Artisanal and small-scale gold mining (ASGM) represents one of the most hazardous work environments. While formalization of this sector has been suggested (e.g., Minamata Convention) as a means to improve working conditions, we are unaware of empirical evidence that supports this notion. This study aimed to compare sociodemographic profiles, work profiles, and injury rates among miners working in licensed versus un-licensed ASGM sites. In the Tarkwa mining region of Ghana, 404 small-scale miners were recruited in 2014 and interviewed regarding their occupational injury experiences over the preceding 10 years. Workers were drawn from 9 mining sites, of which 5 were licensed and 4 were not licensed. Sociodemographic characteristics of miners from the two groups were relatively similar. Those currently working in an un-licensed mine have spent more time in the ASGM sector than those currently working in a licensed mine (94 vs. 70 months). Miners working in an un-licensed site tended to experience more injury episodes (e.g., 26% vs. 8% had 3 or more injury events) and not use personal protective equipment during the time of an injury (92% indicated to not using vs. 73%) when compared to miners working in a licensed site. A total of 121 injury episodes were recorded for 2245 person years of ASGM work. The injury rate for those working in un-licensed mines was 5.9 per 100 person years (59 injuries in 995 person years) versus 5.0 (62 injuries in 1250 person-years) in the licensed mines. When focusing on the male miners, there was a significant difference in injury rates between those working in a licensed mine (4.2 per 100 person years) versus an un-licensed mine (6.1 per 100 person years). These findings advance our understanding of injuries amongst ASGM workers, and help identify important differences in socio-demographics, work profiles, and injury rates between miners working in a licensed versus and un-licensed site. The findings suggest that certain working conditions in a licensed site may be safer.

Trends in the job market of nurses in the view of managers.

PubMed

Oliveira, Jonas Sâmi Albuquerque de; Pires, Denise Elvira Pires de; Alvarez, Ângela Maria; Sena, Roseni Rosângela de; Medeiros, Soraya Maria de; Andrade, Selma Regina de

2018-01-01

to identify and interpret the main trends of the labor market for nurses in Rio Grande do Norte, based on the opinion of managers of training institutions and employers. Data were collected through interviews with key informants, organized using Atlas.ti software resources and examined under the thematic content review. the study showed six trends in the labor market of nurses: availability of professionals to the market; worsening working conditions with precariousness; indication for insertion in employment; unemployment for nurses; shortage of nurses; and the existence of a cooperative of nursing professionals. the current scenario of growth in the number of registered nurses without the expansion of the job supply has remained, unemployment tends to increase and work conditions will worsen.

A Proposed Collaborative Framework for Prefabricated Housing Construction Using RFID Technology

NASA Astrophysics Data System (ADS)

Charnwasununth, Phatsaphan; Yabuki, Nobuyoshi; Tongthong, Tanit

Despite the popularity of prefabricated housing construction in Thailand and many other countries, due to the lack of collaboration in current practice, undesired low productivity and a number of mistakes are identified. This research proposes a framework to raise the collaborative level for improving productivity and reducing mistake occurrences at sites. In this framework, RFID system bridges the gap between the real situation and the design, and the proposed system can cope with the unexpected construction conditions by generating proper alternatives. This system is composed of PDAs, RFID readers, laptop PCs, and a desktop PC. Six main modules and a database system are implemented in laptop PCs for recording actual site conditions, generating working alternatives, providing related information, and evaluating the work.

Evaluation of Supercapacitors Effects on Hybrid Energy Systems for Automotive

NASA Astrophysics Data System (ADS)

Lungoci, Carmen; Helerea, Elena

This work aims at evaluating the effects of the supercapacitors presence in hybrid energy systems used in automotive. The design and the electrical schema of a hybrid energy system that contains batteries and supercapacitors and propel a synchronous motor are purposed. The motor operating regime is described, detailing the drive evolution of the cycle speed imposed. In these conditions, to model the systems behavior, simulations developed in Matlab/Simulink environment are carried out. Two energies management strategies for the ensemble energy system-motor are implemented. Simulations are done and the energy management is discussed, making the comparative analyses. Applying a current control strategy on the supercapacitors, under two working conditions, functional diagrams are showed and compared. The results obtained highlight the advantages of the supercapacitors.

The influence of winding direction of two-layer HTS DC cable on the critical current

NASA Astrophysics Data System (ADS)

Vyatkin, V. S.; Kashiwagi, K.; Ivanov, Y. V.; Otabe, E. S.; Yamaguchi, S.

2017-09-01

The design of twist pitch and direction of winding in multilayer HTS coaxial cable is important. For HTS AC transmitting cables, the main condition of twist pitch is the balance of inductances of each layer for providing the current balance between layers. In this work, the finite element method analysis for the coaxial cables with both same and opposite directions winding is used to calculate magnetic field distribution, and critical current of the cable is estimated. It was found that the critical current of the cable with same direction winding is about 10 percent higher than that in the case of the cable with the opposite direction winding.

The influence of secondary conditions on job acquisition and retention in adults with spinal cord injury.

PubMed

Meade, Michelle A; Forchheimer, Martin B; Krause, James S; Charlifue, Susan

2011-03-01

To examine the associations of job acquisition and job retention to secondary conditions, hospitalizations, and nursing home stays for adults with spinal cord injury (SCI). Retrospective analysis of longitudinal data from multicenter study. Community setting. Two samples of adults participating in the SCI Model Systems; the first sample consisted of persons who reported being unemployed at follow-up (n=9501); the second sample consisted of those who reported working at follow-up (n=5,150). Not applicable. Job acquisition (change from not working at 1 anniversary of injury to working at the following data collection) and job retention (maintenance of work between 2 assessment periods). Discrete time hazard modeling was used to assess how secondary conditions affect job acquisition. After controlling for the effects of demographic and injury characteristics, hospitalizations within the last 12 months were associated with decreased chance of having obtained employment. Hierarchic logistic regression analyses were used to examine job retention. Hospitalizations and the presence of PUs were associated with lower odds of job retention once demographic and injury characteristics were controlled. Secondary conditions from the previous assessment period were not significantly related to either job acquisition or job retention after the variance from demographic and injury characteristics and current secondary conditions were controlled. Hospitalization, as well as a limited number of secondary conditions, were associated with reduced odds of both job acquisition and job retention among adults with SCI. Interventions that can prevent secondary conditions and reduce the need for hospitalizations may be beneficial in improving employment for this population. Copyright © 2011 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Applying Best Practices to Florida Local Government Retrofit Programs

DOE Office of Scientific and Technical Information (OSTI.GOV)

McIlvaine, J.; Sutherland, K.

In some communities, local government and non-profit entities have funds to purchase and renovate distressed, foreclosed homes for resale in the affordable housing market. Numerous opportunities to improve whole house energy efficiency are inherent in these comprehensive renovations. BA-PIRC worked together in a multi-year field study making recommendations in individual homes, meanwhile compiling improvement costs, projected energy savings, practical challenges, and labor force factors surrounding common energy-related renovation measures. The field study, Phase 1 of this research, resulted in a set of best practices appropriate to the current labor pool and market conditions in central Florida to achieve projected annualmore » energy savings of 15-30% and higher. This report describes Phase 2 of the work where researchers worked with a local government partner to implement and refine the 'current best practices.' A simulation study was conducted to characterize savings potential under three sets of conditions representing varying replacement needs for energy-related equipment and envelope components. The three scenarios apply readily to the general remodeling industry as for renovation of foreclosed homes for the affordable housing market. Our new local government partner, the City of Melbourne, implemented the best practices in a community-scale renovation program that included ten homes in 2012.« less

Existing Whole-House Solutions Case Study: Applying Best Practices to Florida Local Government Retrofit Programs - Central Florida

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

In some communities, local government and non-profit entities have funds to purchase and renovate distressed, foreclosed homes for resale in the affordable housing market. Numerous opportunities to improve whole house energy efficiency are inherent in these comprehensive renovations. BA-PIRC worked together in a multiyear field study making recommendations in individual homes, meanwhile compiling improvement costs, projected energy savings, practical challenges, and labor force factors surrounding common energy-related renovation measures. The field study, Phase 1 of this research, resulted in a set of best practices appropriate to the current labor pool and market conditions in central Florida to achieve projected annualmore » energy savings of 15%-30% and higher. This case study describes Phase 2 of the work where researchers worked with a local government partner to implement and refine the "current best practices". A simulation study was conducted to characterize savings potential under three sets of conditions representing varying replacement needs for energy-related equipment and envelope components. The three scenarios apply readily to the general remodeling industry as for renovation of foreclosed homes for the affordable housing market. The new local government partner, the City of Melbourne, implemented the best practices in a community-scale renovation program that included ten homes in 2012.« less

Applying Best Practices to Florida Local Government Retrofit Programs, Central Florida (Fact Sheet)

DOE Office of Scientific and Technical Information (OSTI.GOV)

None, None

In some communities, local government and non-profit entities have funds to purchase and renovate distressed, foreclosed homes for resale in the affordable housing market. Numerous opportunities to improve whole house energy efficiency are inherent in these comprehensive renovations. BA-PIRC worked together in a multi-year field study making recommendations in individual homes, meanwhile compiling improvement costs, projected energy savings, practical challenges, and labor force factors surrounding common energy-related renovation measures. The field study, Phase 1 of this research, resulted in a set of best practices appropriate to the current labor pool and market conditions in central Florida to achieve projected annualmore » energy savings of 15-30% and higher. This report describes Phase 2 of the work where researchers worked with a local government partner to implement and refine the "current best practices". A simulation study was conducted to characterize savings potential under three sets of conditions representing varying replacement needs for energy-related equipment and envelope components. The three scenarios apply readily to the general remodeling industry as for renovation of foreclosed homes for the affordable housing market. Our new local government partner, the City of Melbourne, implemented the best practices in a community-scale renovation program that included ten homes in 2012.« less

Applying Best Practices to Florida Local Government Retrofit Programs

DOE Office of Scientific and Technical Information (OSTI.GOV)

McIlvaine, J.; Sutherland, K.

In some communities, local government and non-profit entities have funds to purchase and renovate distressed, foreclosed homes for resale in the affordable housing market. Numerous opportunities to improve whole house energy efficiency are inherent in these comprehensive renovations. BA-PIRC worked together in a multiyear field study making recommendations in individual homes, meanwhile compiling improvement costs, projected energy savings, practical challenges, and labor force factors surrounding common energy-related renovation measures. The field study, Phase 1 of this research, resulted in a set of best practices appropriate to the current labor pool and market conditions in central Florida to achieve projected annualmore » energy savings of 15%-30% and higher. This report describes Phase 2 of the work where researchers worked with a local government partner to implement and refine the "current best practices". A simulation study was conducted to characterize savings potential under three sets of conditions representing varying replacement needs for energy-related equipment and envelope components. The three scenarios apply readily to the general remodeling industry as for renovation of foreclosed homes for the affordable housing market. The new local government partner, the City of Melbourne, implemented the best practices in a community-scale renovation program that included ten homes in 2012.« less

Configurations of power relations in the Brazilian emergency care system: analyzing a context of visible practices.

PubMed

Velloso, Isabela; Ceci, Christine; Alves, Marilia

2013-09-01

In this paper, we make explicit the changing configurations of power relations that currently characterize the Brazilian Emergency Care System (SAMU) team in Belo Horizonte, Brazil. The SAMU is a recent innovation in Brazilian healthcare service delivery. A qualitative case study methodology was used to explore SAMU's current organizational arrangements, specifically the power relations that have developed and that demonstrate internal team struggles over space and defense of particular occupational interests. The argument advanced in this paper is that these professionals are developing their work in conditions of exposure, that is, they are always being observed by someone, and that such observational exposure provides the conditions whereby everyday emergency care practices are enacted such that practice is shaped by, as well as shapes, particular, yet recognizable power relationships. Data were collected through the observation of the SAMU's work processes and through semi-structured interviews. Research materials were analyzed using discourse analysis. In the emergency care process of work, visibility is actually embedded in the disciplinary context and can thus be analyzed as a technique applied to produce disciplined individuals through the simple mechanisms elaborated by Foucault such as hierarchical surveillance, normalizing judgment, and the examination. © 2012 John Wiley & Sons Ltd.

An Exploration of the Factors Considered When Forming Expectations for Returning to Work following Sickness Absence Due to a Musculoskeletal Condition.

PubMed

Young, Amanda E; Choi, YoonSun; Besen, Elyssa

2015-01-01

Workers' own expectations for returning to work following a period of sickness absence have been found to be one of the best predictors of future work status; however, there is a limited understanding of why people expect what they do. The current study was undertaken with the aim of determining what people take into consideration when forming their expectations for returning to work. Thirty-four people (8 women, 26 men), who were off work due to a musculoskeletal condition, participated in one of 14 focus groups. Participants were aged 25 to 65 (M = 45, SD = 12.6), and all had been out of work for 3 months or less. All participants reported expecting to return to work, with the most common timeframe being approximately 30 days (Range = 1 day-12 months). When explaining what they thought about when forming their expectations, participants referenced numerous considerations. Much of what was spoken about could be compartmentalized to reflect features of themselves, their condition, or their broader environmental contexts. Participant's subjective experience of these features influenced his or her expectations. Prominent themes included concerns about employability, a desire to get back to normal, no job to go back to, mixed emotions, re-injury concerns, the judgments of workplace stakeholders, being needed by their employer, waiting for input, until the money runs out, and working out what was in their best interest. Indications are that many of the reported considerations are amenable to intervention, suggesting opportunities to assist workers in the process of returning to work.

Life-Course Effects of Work and Family Circumstances on Children.

ERIC Educational Resources Information Center

Cooksey, Elizabeth C.; Menaghan, Elizabeth G.; Jekielek, Susan M.

1997-01-01

Data from the National Longitudinal Survey of Youth on 2,342 children aged 6-7 and born between 1979 and 1984 suggest that children's behavior problems are related to current family and parental employment conditions and earlier maternal resources and vulnerabilities (early deviance, self-esteem in 1980, smoking during pregnancy, cognitive…

Girls in the Education Market: Choice, Competition and Complexity.

ERIC Educational Resources Information Center

Ball, Stephen J.; Gewirtz, Sharon

1997-01-01

Considers the role of girls' schools in the United Kingdom education market and the positioning and "value" of girls by examining the workings of market forces in education. It reveals that current conditions of competition offer some advantages to girls but that these advantages have to be set against the continuing contradictions and…

Shear design of wood beams : state of the art

Treesearch

Lawrence A. Soltis; Terry D. Gerhardt

1988-01-01

Current shear design technology in the United States for lumber or glued- laminated beams is confusing. This report summarizes shear stress and strength research including both analytical and experimental approaches. Both checked and unchecked beams are included. The analytical work has been experimentally verified for only limited load conditions and span-to- depth...

Comparisons of Performance and Job Insecurity in Union and Nonunion Sites of a Manufacturing Company

ERIC Educational Resources Information Center

Filipkowski, Monica; Johnson, C. Merle

2008-01-01

Layoffs and employment changes caused by current economic conditions have significant effects on employee work behavior and emotions as well as organizational outcomes. We examined the relationships between measures of job insecurity, organizational commitment, turnover, absenteeism, and worker performance within a manufacturer in Chapter 11…

Raising Teacher Salaries: The Funds Are There.

ERIC Educational Resources Information Center

Haberman, Martin

2005-01-01

School districts currently spend $2.6 billion annually on maintaining a system of recruiting and hiring teachers who quit or fail. The 120 major urban districts are the primary locus of this teacher churn. The causes include the negative conditions of work in these districts, the impersonal hiring procedures which recruit and hire the wrong people…

Tribal, Proletarian and Entrepreneurial Career Stories: Junior Academics as a Case in Point

ERIC Educational Resources Information Center

Ylijoki, Oili-Helena; Henriksson, Lea

2017-01-01

This paper explores the career-building of junior academics in the current higher education environment, which is characterised by short-term employment conditions. The paper is based on focus group discussions with Finnish early career academics working in the social sciences. Drawing upon a narrative approach, five career stories are…

Forest productivity: an integrated research and development program

Treesearch

Daniel C. Dey; Thomas R. Crow; Don E. Riemenschneider

2003-01-01

In 2000, the North Central Research Station initiated the Forest Productivity Integrated Research Program (North Central Research Station 2001). This program combines the efforts of scientists from across the Station's 13 research work units to examine the current condition of the forests in the North Central Region and their prospects for producing wood and fiber...

Somalia: Current Conditions and Prospects for a Lasting Peace

DTIC Science & Technology

2010-10-08

ship, MV Faina, which was carrying 33 T-72 tanks and other weapons and a Japanese -owned ship, MV Chemstar, were released. In February 2010, a Libyan...The ICU was accused of shutting down cinemas and prohibiting women from working. Some of these measures were taken by the Courts, although for

Wundt on Introspection: Reflection on Current Controversy.

ERIC Educational Resources Information Center

Leahey, Thomas H.; And Others

Wilhelm Wundt provided a complete and concise description of his introspective method in a 1907 paper criticizing the thought experiments conducted by the Wurzburg psychologists. This major work is now being translated for the first time. For Wundt, the role of experimental method was to ensure the best conditions for observing and reporting…

The Impact of Motivational and Metacognitive Cultural Intelligence on the Study Abroad Experience

ERIC Educational Resources Information Center

Racicot, Bernadette M.; Ferry, Diane L.

2016-01-01

The current study used a time-lagged design to examine the effects of Metacognitive and Motivational Cultural Intelligence (CQ) prior to studying abroad on the experiential behavior of students during their study abroad trip and their future interest in work and study abroad opportunities. Using Hayes' conditional process analysis, results…

"Brain Drain" from Turkey: Survey Evidence of Student Non-Return.

ERIC Educational Resources Information Center

Tansel, Aysit; Gungor, Nil Demet

2003-01-01

An Internet survey of Turkish students studying abroad received 1,103 responses. Although 53% initially intended to return, only 13.5% have that intention currently. Reasons for staying abroad include better career prospects, Turkish economic conditions, lack of relevant work in Turkey, and avoidance of compulsory military service. (Contains 28…

Diversity Exiting the Academy: Influential Factors for the Career Choice of Well-Represented and Underrepresented Minority Scientists

ERIC Educational Resources Information Center

Layton, Rebekah L.; Brandt, Patrick D.; Freeman, Ashalla M.; Harrell, Jessica R.; Hall, Joshua D.; Sinche, Melanie

2016-01-01

A national sample of PhD-trained scientists completed training, accepted subsequent employment in academic and nonacademic positions, and were queried about their previous graduate training and current employment. Respondents indicated factors contributing to their employment decision (e.g., working conditions, salary, job security). The data…

Interference Impacts Working Memory in Mild Cognitive Impairment

PubMed Central

Aurtenetxe, Sara; García-Pacios, Javier; del Río, David; López, María E.; Pineda-Pardo, José A.; Marcos, Alberto; Delgado Losada, Maria L.; López-Frutos, José M.; Maestú, Fernando

2016-01-01

Mild cognitive impairment (MCI) is considered a transitional stage between healthy aging and dementia, specifically Alzheimer's disease (AD). The most common cognitive impairment of MCI includes episodic memory loss and difficulties in working memory (WM). Interference can deplete WM, and an optimal WM performance requires an effective control of attentional resources between the memoranda and the incoming stimuli. Difficulties in handling interference lead to forgetting. However, the interplay between interference and WM in MCI is not well-understood and needs further investigation. The current study investigated the effect of interference during a WM task in 20 MCIs and 20 healthy elder volunteers. Participants performed a delayed match-to-sample paradigm which consisted in two interference conditions, distraction and interruption, and one control condition without any interference. Results evidenced a disproportionate impact of interference on the WM performance of MCIs, mainly in the presence of interruption. These findings demonstrate that interference, and more precisely interruption, is an important proxy for memory-related deficits in MCI. Thus, the current findings reveal novel evidence regarding the causes of WM forgetting in MCI patients, associated with difficulties in the mechanisms of attentional control. PMID:27790082

Phase Equilibrium of TiO2 Nanocrystals in Flame-Assisted Chemical Vapor Deposition.

PubMed

Liu, Changran; Camacho, Joaquin; Wang, Hai

2018-01-19

Nano-scale titanium oxide (TiO 2 ) is a material useful for a wide range of applications. In a previous study, we showed that TiO 2 nanoparticles of both rutile and anatase crystal phases could be synthesized over the size range of 5 to 20 nm in flame-assisted chemical vapor deposition. Rutile was unexpectedly dominant in oxygen-lean synthesis conditions, whereas anatase is the preferred phase in oxygen-rich gases. The observation is in contrast to the 14 nm rutile-anatase crossover size derived from the existing crystal-phase equilibrium model. In the present work, we made additional measurements over a wider range of synthesis conditions; the results confirm the earlier observations. We propose an improved model for the surface energy that considers the role of oxygen desorption at high temperatures. The model successfully explains the observations made in the current and previous work. The current results provide a useful path to designing flame-assisted chemical vapor deposition of TiO 2 nanocrystals with controllable crystal phases. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Motivational determinants among physicians in Lahore, Pakistan.

PubMed

Malik, Ahmad Azam; Yamamoto, Shelby Suzanne; Souares, Aurélia; Malik, Zeeshan; Sauerborn, Rainer

2010-07-09

Human resource crises in developing countries have been identified as a critical aspect of poor quality and low accessibility in health care. Worker motivation is an important facet of this issue. Specifically, motivation among physicians, who are an important bridge between health systems and patients, should be considered. This study aimed to identify the determinants of job motivation among physicians, a neglected perspective, especially in developing countries. A stratified random sample of 360 physicians was selected from public primary, public secondary and public and private tertiary health facilities in the Lahore district, Pakistan. Pretested, semi-structured, self-administered questionnaires were used. For the descriptive part of this study, physicians were asked to report their 5 most important work motivators and demotivators within the context of their current jobs and in general. Responses were coded according to emergent themes and frequencies calculated. Of the 30 factors identified, 10 were classified as intrinsic, 16 as organizational and 4 as socio-cultural. Intrinsic and socio-cultural factors like serving people, respect and career growth were important motivators. Conversely, demotivators across setups were mostly organizational, especially in current jobs. Among these, less pay was reported the most frequently. Fewer opportunities for higher qualifications was a demotivator among primary and secondary physicians. Less personal safety and poor working conditions were important in the public sector, particularly among female physicians. Among private tertiary physicians financial incentives other than pay and good working conditions were motivators in current jobs. Socio-cultural and intrinsic factors like less personal and social time and the inability to financially support oneself and family were more important among male physicians. Motivational determinants differed across different levels of care, sectors and genders. Nonetheless, the important motivators across setups in this study were mostly intrinsic and socio-cultural, which are difficult to affect while the demotivators were largely organizational. Many can be addressed even at the facility level such as less personal safety and poor working conditions. Thus, in resource limited settings a good strategic starting point could be small scale changes that may markedly improve physicians' motivation and subsequently the quality of health care.

Work Engagement, Burnout and Personal Accomplishments Among Social Workers: A Comparison Between Those Working in Children and Adults' Services in England.

PubMed

Hussein, Shereen

2018-04-26

Social workers (SWs) provide emotional and practical support to vulnerable service users who are likely to suffer from emotional trauma and mental health conditions. Stress and burnout levels are reported to be high among SWs, however, little is known about their relationships with different characteristics. The current article utilises unique and large dataset (n = 3786) on SWs working in adults and children's services to examine factors associated with burnout. Employing job-demand/resources model and structural equations modelling, we highlight the varying significant impact of work-engagement, administrative support and work experience as moderating factors to burnout across adult and children service specialism in this sample.

Women in dentistry in South Africa: a survey of their experiences and opinions.

PubMed

Naidoo, S

2005-08-01

Women form an increasingly important part of the dentally trained workforce in South Africa. However, little is known about the professional issues and work-related problems affecting women dentists. A postal survey was undertaken of registered female dental practitioners in the country, with the aim to document their experiences. The survey (i) ascertained their current pattern of work, (ii) identified factors influencing their work patterns and (iii) identified factors that would help women remain in the profession or re-enter it more easily after an absence. A self-administered 50-item questionnaire containing open and closed-ended questions was used. Questions related to professional status, working patterns, practice ownership, postgraduate qualifications and career satisfaction. Nine hundred and sixty questionnaires were sent out and 280 were returned (29% response rate). Although a significant majority were currently practicing (96%), about 20% were employed or worked part-time and 7 reported that they were not in practice at the time of the survey for various reasons including maternity leave, ill-health, retirement or that they were now working outside the dental field. Major factors identified in this study were the women's dual responsibility at home and at work. Few women find themselves in specialist practice, although 68% indicated that they would liked to have specialised. Home responsibilities and inflexible working conditions were commonly reported difficulties experienced with further studies. In addition, the lack of part-time training and the geographical location of training facilities also played a role. Women dentists need more flexible working schedules and conditions of employment. Part-time training and part-time career options should be extended. Retraining and refresher courses for Women dentists who have had a break in their careers should be available to enable them to return sooner and more easily to practice. Tertiary training dental facilities throughout the country should take up this challenge and run courses that are tailored to the local need and domestic commitments of the women involved.

Coherence enhanced quantum metrology in a nonequilibrium optical molecule

NASA Astrophysics Data System (ADS)

Wang, Zhihai; Wu, Wei; Cui, Guodong; Wang, Jin

2018-03-01

We explore the quantum metrology in an optical molecular system coupled to two environments with different temperatures, using a quantum master equation beyond secular approximation. We discover that the steady-state coherence originating from and sustained by the nonequilibrium condition can enhance quantum metrology. We also study the quantitative measures of the nonequilibrium condition in terms of the curl flux, heat current and entropy production at the steady state. They are found to grow with temperature difference. However, an apparent paradox arises considering the contrary behaviors of the steady-state coherence and the nonequilibrium measures in relation to the inter-cavity coupling strength. This paradox is resolved by decomposing the heat current into a population part and a coherence part. Only the latter, the coherence part of the heat current, is tightly connected to the steady-state coherence and behaves similarly with respect to the inter-cavity coupling strength. Interestingly, the coherence part of the heat current flows from the low-temperature reservoir to the high-temperature reservoir, opposite to the direction of the population heat current. Our work offers a viable way to enhance quantum metrology for open quantum systems through steady-state coherence sustained by the nonequilibrium condition, which can be controlled and manipulated to maximize its utility. The potential applications go beyond quantum metrology and extend to areas such as device designing, quantum computation and quantum technology in general.

Telerobotic Perception During Asteroid and Mars Regolith Operations Project

NASA Technical Reports Server (NTRS)

Gaddis, Steven; Zeitlin, Nancy (Compiler); Mueller, Robert (Compiler)

2015-01-01

Current space telerobotic systems are constrained to only operating in bright light and dust-free conditions. This project will study the effects of difficult lighting and dust conditions on telerobotic perception systems to better assess and refine regolith operations on other neighboring celestial bodies. In partnership with Embry-Riddle Aeronautical University and Caterpillar, Inc., optical, LiDAR and RADAR sensing equipment will be used in performing the study. This project will create a known dust environment in the Swamp Works Granular Mechanics & Regolith Operations (GMRO) Laboratory regolith test bin to characterize the behavior of the sensing equipment in various calibrated lighting and dust conditions. It will also identify potential methods for mitigating the impacts of these undesirable conditions on the performance of the sensing equipment. Enhancing the capability of telerobotic perception systems will help improve life on earth for those working in dangerous, dusty mining conditions, as well as help advance the same technologies used for safer self-driving automobiles in various lighting and weather conditions. It will also prove to be a critical skill needed for advancing robotic and human exploration throughout our solar system, for activities such as mining on an asteroid or pioneering the first colony on Mars.

Chronic and integrated care in Catalonia

PubMed Central

Contel, Juan Carlos; Ledesma, Albert; Blay, Carles; Mestre, Assumpció González; Cabezas, Carmen; Puigdollers, Montse; Zara, Corine; Amil, Paloma; Sarquella, Ester; Constante, Carles

2015-01-01

Introduction The Chronicity Prevention and Care Programme set up by the Health Plan for Catalonia 2011–2015 has been an outstanding and excellent opportunity to create a new integrated care model in Catalonia. People with chronic conditions require major changes and transformation within the current health and social system. The new and gradual context of ageing, increase in the number of chronic diseases and the current fragmented system requires this transformation to be implemented. Method The Chronicity Prevention and Care Programme aims to implement actions which drive the current system towards a new scenario where organisations and professionals must work collaboratively. New tools should facilitate this new context- or work-like integrated health information systems, an integrative financing and commissioning scheme and provide a new approach to virtual care by substituting traditional face-to-face care with transfer and shared responsibilities between patients, citizens and health care professionals. Results It has been observed some impact reducing the rate of emergency admissions and readmission related to chronic conditions and better outcome related to better chronic disease control. Some initiative like the Catalan Expert Patient Program has obtained good results and an appropriate service utilization. Discussion The implementation of a Chronic Care Program show good results but it is expected that the new integrated health and social care agenda could provoke a real change and transformation. Some of the results related to better health outcomes and a decrease in avoidable hospital admissions related to chronic conditions confirm we are on the right track to make our health and social system more sustainable for the decades to come. PMID:26150763

Statistical analysis of the effect of temperature and inlet humidities on the parameters of a semiempirical model of the internal resistance of a polymer electrolyte membrane fuel cell

NASA Astrophysics Data System (ADS)

Giner-Sanz, J. J.; Ortega, E. M.; Pérez-Herranz, V.

2018-03-01

The internal resistance of a PEM fuel cell depends on the operation conditions and on the current delivered by the cell. This work's goal is to obtain a semiempirical model able to reproduce the effect of the operation current on the internal resistance of an individual cell of a commercial PEM fuel cell stack; and to perform a statistical analysis in order to study the effect of the operation temperature and the inlet humidities on the parameters of the model. First, the internal resistance of the individual fuel cell operating in different operation conditions was experimentally measured for different DC currents, using the high frequency intercept of the impedance spectra. Then, a semiempirical model based on Springer and co-workers' model was proposed. This model is able to successfully reproduce the experimental trends. Subsequently, the curves of resistance versus DC current obtained for different operation conditions were fitted to the semiempirical model, and an analysis of variance (ANOVA) was performed in order to determine which factors have a statistically significant effect on each model parameter. Finally, a response surface method was applied in order to obtain a regression model.

Motivations for entry into sex work and HIV risk among mobile female sex workers in India.

PubMed

Saggurti, Niranjan; Verma, Ravi K; Halli, Shiva S; Swain, Suvakanta N; Singh, Rajendra; Modugu, Hanimi Reddy; Ramarao, Saumya; Mahapatra, Bidhubhusan; Jain, Anrudh K

2011-09-01

This paper assesses the reasons for entry into sex work and its association with HIV risk behaviours among mobile female sex workers (FSWs) in India. Data were collected from a cross-sectional survey conducted in 22 districts across four high HIV prevalence states in India during 2007-2008. Analyses were limited to 5498 eligible mobile FSWs. The reasons given by FSWs for entering sex work and associations with socio-demographic characteristics were assessed. Reported reasons for entering sex work include poor or deprived economic conditions; negative social circumstances in life; own choice; force by an external person; and family tradition. The results from multivariate analyses indicate that those FSWs who entered sex work due to poor economic conditions or negative social circumstances in life or force demonstrated elevated levels of current inconsistent condom use as well as in the past in comparison with those FSWs who reported entering sex work by choice or family tradition. This finding indicates the need for a careful assessment of the pre-entry contexts among HIV prevention interventions since these factors may continue to hinder the effectiveness of efforts to reduce the spread of HIV/AIDS in India and elsewhere.

Prediction of Tidal Elevations and Barotropic Currents in the Gulf of Bone

NASA Astrophysics Data System (ADS)

Purnamasari, Rika; Ribal, Agustinus; Kusuma, Jeffry

2018-03-01

Tidal elevation and barotropic current predictions in the gulf of Bone have been carried out in this work based on a two-dimensional, depth-integrated Advanced Circulation (ADCIRC-2DDI) model for 2017. Eight tidal constituents which were obtained from FES2012 have been imposed along the open boundary conditions. However, even using these very high-resolution tidal constituents, the discrepancy between the model and the data from tide gauge is still very high. In order to overcome such issues, Green’s function approach has been applied which reduced the root-mean-square error (RMSE) significantly. Two different starting times are used for predictions, namely from 2015 and 2016. After improving the open boundary conditions, RMSE between observation and model decreased significantly. In fact, RMSEs for 2015 and 2016 decreased 75.30% and 88.65%, respectively. Furthermore, the prediction for tidal elevations as well as tidal current, which is barotropic current, is carried out. This prediction was compared with the prediction conducted by Geospatial Information Agency (GIA) of Indonesia and we found that our prediction is much better than one carried out by GIA. Finally, since there is no tidal current observation available in this area, we assume that, when tidal elevations have been fixed, then the tidal current will approach the actual current velocity.

Methods of evaluating protective clothing relative to heat and cold stress: thermal manikin, biomedical modeling, and human testing.

PubMed

O'Brien, Catherine; Blanchard, Laurie A; Cadarette, Bruce S; Endrusick, Thomas L; Xu, Xiaojiang; Berglund, Larry G; Sawka, Michael N; Hoyt, Reed W

2011-10-01

Personal protective equipment (PPE) refers to clothing and equipment designed to protect individuals from chemical, biological, radiological, nuclear, and explosive hazards. The materials used to provide this protection may exacerbate thermal strain by limiting heat and water vapor transfer. Any new PPE must therefore be evaluated to ensure that it poses no greater thermal strain than the current standard for the same level of hazard protection. This review describes how such evaluations are typically conducted. Comprehensive evaluation of PPE begins with a biophysical assessment of materials using a guarded hot plate to determine the thermal characteristics (thermal resistance and water vapor permeability). These characteristics are then evaluated on a thermal manikin wearing the PPE, since thermal properties may change once the materials have been constructed into a garment. These data may be used in biomedical models to predict thermal strain under a variety of environmental and work conditions. When the biophysical data indicate that the evaporative resistance (ratio of permeability to insulation) is significantly better than the current standard, the PPE is evaluated through human testing in controlled laboratory conditions appropriate for the conditions under which the PPE would be used if fielded. Data from each phase of PPE evaluation are used in predictive models to determine user guidelines, such as maximal work time, work/rest cycles, and fluid intake requirements. By considering thermal stress early in the development process, health hazards related to temperature extremes can be mitigated while maintaining or improving the effectiveness of the PPE for protection from external hazards.

NIDDK international conference report on diabetes and depression: current understanding and future directions.

PubMed

Holt, Richard I G; de Groot, Mary; Lucki, Irwin; Hunter, Christine M; Sartorius, Norman; Golden, Sherita H

2014-08-01

Comorbid diabetes and depression are a major clinical challenge as the outcomes of each condition are worsened by the other. This article is based on the presentations and discussions during an international meeting on diabetes and depression convened by the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) in collaboration with the National Institute of Mental Health and the Dialogue on Diabetes and Depression. While the psychological burden of diabetes may contribute to depression in some cases, this explanation does not sufficiently explain the relationship between these two conditions. Shared biological and behavioral mechanisms, such as hypothalamic-pituitary-adrenal axis activation, inflammation, autonomic dysfunction, sleep disturbance, inactive lifestyle, poor dietary habits, and environmental and cultural risk factors, are important to consider in understanding the link between depression and diabetes. Both individual psychological and pharmacological depression treatments are effective in people with diabetes, but the current range of treatment options is limited and has shown mixed effects on glycemic outcomes. More research is needed to understand what factors contribute to individual differences in vulnerability, treatment response, and resilience to depression and metabolic disorders across the life course and how best to provide care for people with comorbid diabetes and depression in different health care settings. Training programs are needed to create a cross-disciplinary workforce that can work in different models of care for comorbid conditions. © 2014 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

Ergonomic evaluation and comparison of wood harvesting systems in Northwest Russia.

PubMed

Gerasimov, Yuri; Sokolov, Anton

2014-03-01

A comparison of 14 currently applicable wood harvesting systems was assessed with respect to ergonomic point of view. For this purpose, the research method, based on the Hodges-Lehmann rule and the integrated work-severity rate of single machinery, was developed for ergonomic evaluation of cut-to-length, tree-length and full-tree harvesting systems. Altogether, about 130 different parameters of 36 units of equipment that impact on the ergonomics and work conditions were measured and estimated in interviews undertaken directly at forestry harvesting workplaces in 15 logging companies in the Republic of Karelia, Northwest Russia. Then the results were compared to the effective norms, and the degree of compliance with the stipulated values was determined. The estimates obtained for the degree of compliance were combined. This permits a direct comparison of the workload on forestry harvesting workers such as operators, lumberjacks and choker setters. In many respects, the current ergonomic standard is standard, except for the operators of cable skidders, chainsaws and choker settings. Visibility and work postures were considered to be the most critical features influencing the operator's performance. Problems still exist, despite the extensive development of cabs. The best working conditions in terms of harvesting systems were provided by "harvester + forwarder" in cut-to-length harvesting, and "feller-buncher + grapple skidder" in full-tree harvesting. The motor-manual tree-length harvesting performed with cable skidders showed the worst results in terms of ergonomics. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

The technique of entropy optimization in motor current signature analysis and its application in the fault diagnosis of gear transmission

NASA Astrophysics Data System (ADS)

Chen, Xiaoguang; Liang, Lin; Liu, Fei; Xu, Guanghua; Luo, Ailing; Zhang, Sicong

2012-05-01

Nowadays, Motor Current Signature Analysis (MCSA) is widely used in the fault diagnosis and condition monitoring of machine tools. However, although the current signal has lower SNR (Signal Noise Ratio), it is difficult to identify the feature frequencies of machine tools from complex current spectrum that the feature frequencies are often dense and overlapping by traditional signal processing method such as FFT transformation. With the study in the Motor Current Signature Analysis (MCSA), it is found that the entropy is of importance for frequency identification, which is associated with the probability distribution of any random variable. Therefore, it plays an important role in the signal processing. In order to solve the problem that the feature frequencies are difficult to be identified, an entropy optimization technique based on motor current signal is presented in this paper for extracting the typical feature frequencies of machine tools which can effectively suppress the disturbances. Some simulated current signals were made by MATLAB, and a current signal was obtained from a complex gearbox of an iron works made in Luxembourg. In diagnosis the MCSA is combined with entropy optimization. Both simulated and experimental results show that this technique is efficient, accurate and reliable enough to extract the feature frequencies of current signal, which provides a new strategy for the fault diagnosis and the condition monitoring of machine tools.

Workout at work: laboratory test of psychological and performance outcomes of active workstations.

PubMed

Sliter, Michael; Yuan, Zhenyu

2015-04-01

With growing concerns over the obesity epidemic in the United States and other developed countries, many organizations have taken steps to incorporate healthy workplace practices. However, most workers are still sedentary throughout the day--a major contributor to individual weight gain. The current study sought to gather preliminary evidence of the efficacy of active workstations, which are a possible intervention that could increase employees' physical activity while they are working. We conducted an experimental study, in which boredom, task satisfaction, stress, arousal, and performance were evaluated and compared across 4 randomly assigned conditions: seated workstation, standing workstation, cycling workstation, and walking workstation. Additionally, body mass index (BMI) and exercise habits were examined as moderators to determine whether differences in these variables would relate to increased benefits in active conditions. The results (n = 180) showed general support for the benefits of walking workstations, whereby participants in the walking condition had higher satisfaction and arousal and experienced less boredom and stress than those in the passive conditions. Cycling workstations, on the other hand, tended to relate to reduced satisfaction and performance when compared with other conditions. The moderators did not impact these relationships, indicating that walking workstations might have psychological benefits to individuals, regardless of BMI and exercise habits. The results of this study are a preliminary step in understanding the work implications of active workstations. (c) 2015 APA, all rights reserved).

Age-related changes in decision making: comparing informed and noninformed situations.

PubMed

Van Duijvenvoorde, Anna C K; Jansen, Brenda R J; Bredman, Joren C; Huizenga, Hilde M

2012-01-01

Advantageous decision making progressively develops into early adulthood, most specifically in complex and motivationally salient decision situations in which direct feedback on gains and losses is provided (Figner & Weber, 2011). However, the factors that underlie this developmental improvement in decision making are still not well understood. The current study therefore investigates 2 potential factors, long-term memory and working memory, by assigning a large developmental sample (7-29 years of age) to a condition with either high or low demands on long-term and working memory. The first condition featured an age-adapted version of the Iowa Gambling Task (IGT; Bechara, Damasio, Damasio, & Anderson, 1994; i.e., a noninformed situation), whereas the second condition provided an external store where explicit information on gains, losses, and probabilities per choice option was presented (i.e., an informed situation). Consistent with previous developmental IGT studies, children up to age 12 did not learn to prefer advantageous options in the noninformed condition. In contrast, all age groups learned to prefer the advantageous options in the informed conditions, although a slight developmental increase in advantageous decision making remained. These results indicate that lowering dependence on long-term and working memory improves children's advantageous decision making. The results additionally suggest that other factors, like inhibitory control processes, may play an additional role in the development of advantageous decision making.

Effects of Aging Stereotype Threat on Working Self-Concepts: An Event-Related Potentials Approach

PubMed Central

Zhang, Baoshan; Lin, Yao; Gao, Qianyun; Zawisza, Magdalena; Kang, Qian; Chen, Xuhai

2017-01-01

Although the influence of stereotype threat (ST) on working self-concepts has been highlighted in recent years, its neural underpinnings are unclear. Notably, the aging ST, which largely influences older adults’ cognitive ability, mental and physical health, did not receive much attention. In order to investigate these issues, electroencephalogram (EEG) data were obtained from older adults during a modified Stroop task using neutral words, positive and negative self-concept words in aging ST vs. neutral control conditions. Results showed longer reaction times (RTs) for identifying colors of words under the aging ST compared to the neutral condition. More importantly, the negative self-concept elicited more positive late P300 amplitudes and enhanced theta band activities compared to the positive self-concept or neutral words under the aging ST condition, whereas no difference was found between these self-concepts and neutral words in the control condition. Furthermore, the aging ST induced smaller theta band synchronization and enhanced alpha band synchronization compared to the control condition. Moreover, we also observed valence differences in self-concepts where the negative self-concept words reduced early P150/N170 complex relative to neutral words. These findings suggest that priming ST could activate negative self-concepts as current working self-concept, and that this influence occurred during a late neural time course. PMID:28747885

Determination of battery stability with advanced diagnostics.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lamb, Joshua; Torres-Castro, Loraine; Orendorff, Christopher

Lithium ion batteries for use in battery electric vehicles (BEVs) has seen considerable expansion over the last several years. It is expected that market share and the total number of BEVs will continue to increase over coming years and that there will be changes in the environmental and use conditions for BEV batteries. Specifically aging of the batteries and exposure to an increased number of crash conditions presents a distinct possibility that batteries may be in an unknown state posing danger to the operator, emergency response personnel and other support personnel. The present work expands on earlier efforts to exploremore » the ability to rapidly monitor using impedance spectroscopy techniques and characterize the state of different battery systems during both typical operations and under abusive conditions. The work has found that it is possible to detect key changes in performance for strings of up to four cells in both series and parallel configurations for both typical and abusive response. As a method the sensitivity for detecting change is enhanced for series configurations. For parallel configurations distinct changes are more difficult to ascertain, but under abusive conditions and for key frequencies it is feasible to use current rapid impedance techniques to identify change. The work has also found it feasible to use rapid impedance as an evaluation method for underload conditions, especially for series strings of cells.« less

The Health and Working Conditions of Women Employed in Child Care

PubMed Central

Linnan, Laura; Arandia, Gabriela; Bateman, Lori A.; Vaughn, Amber; Smith, Natalie; Ward, Dianne

2017-01-01

Over one million women are employed in child care and are among the lowest wage workers in the US. The health and working conditions of 674 child care workers (118 administrators and 556 staff) from 74 centers is described using baseline data from a larger intervention trial. Participants were 39.9 (±13.0) years old; 55.4% African American, 37.1% Caucasian, and 5.3% of Hispanic ethnicity. Seventy-six percent reported having an Associate’s degree or less; 42% were classified as at or below poverty (<$20,000); and exhibited many health risks such as excess weight, insufficient activity, poor diet, and inadequate sleep. We investigated potential differences by income and job category. Lower income participants were significantly more likely to be current smokers (19.9% vs. 11.7%), drink more sweetened beverages (1.9 vs. 1.5), and report higher depressive symptoms (15.5 vs. 12.6). Administrators worked more hours weekly compared to staff (46.4 vs. 40.6), are less active (100 vs. 126 min/week), more sedentary (501 vs. 477 min/day), and reported higher job demands (13.3 vs. 12.5). Given the numerous health issues and challenging work conditions, we hope our results serve as a call to action for addressing low wages and the work environment as a means of influencing the health and well-being of child care workers. PMID:28282940

The Health and Working Conditions of Women Employed in Child Care.

PubMed

Linnan, Laura; Arandia, Gabriela; Bateman, Lori A; Vaughn, Amber; Smith, Natalie; Ward, Dianne

2017-03-09

Over one million women are employed in child care and are among the lowest wage workers in the US. The health and working conditions of 674 child care workers (118 administrators and 556 staff) from 74 centers is described using baseline data from a larger intervention trial. Participants were 39.9 (±13.0) years old; 55.4% African American, 37.1% Caucasian, and 5.3% of Hispanic ethnicity. Seventy-six percent reported having an Associate's degree or less; 42% were classified as at or below poverty (<$20,000); and exhibited many health risks such as excess weight, insufficient activity, poor diet, and inadequate sleep. We investigated potential differences by income and job category. Lower income participants were significantly more likely to be current smokers (19.9% vs. 11.7%), drink more sweetened beverages (1.9 vs. 1.5), and report higher depressive symptoms (15.5 vs. 12.6). Administrators worked more hours weekly compared to staff (46.4 vs. 40.6), are less active (100 vs. 126 min/week), more sedentary (501 vs. 477 min/day), and reported higher job demands (13.3 vs. 12.5). Given the numerous health issues and challenging work conditions, we hope our results serve as a call to action for addressing low wages and the work environment as a means of influencing the health and well-being of child care workers.

Organizational climate and intensive care unit nurses' intention to leave.

PubMed

Stone, Patricia W; Larson, Elaine L; Mooney-Kane, Cathy; Smolowitz, Janice; Lin, Susan X; Dick, Andrew W

2006-07-01

The purposes of this study were to a) estimate the incidence of intensive care units nurses' intention to leave due to working conditions; and b) identify factors predicting this phenomenon. Cross-sectional design. Hospitals and critical care units. Registered nurses (RNs) employed in adult intensive care units. Organizational climate, nurse demographics, intention to leave, and reason for intending to leave were collected using a self-report survey. Nurses were categorized into two groups: a) those intending to leave due to working conditions; and b) others (e.g., those not leaving or retirees). The measure of organizational climate had seven subscales: professional practice, staffing/resource adequacy, nurse management, nursing process, nurse/physician collaboration, nurse competence, and positive scheduling climate. Setting characteristics came from American Hospital Association data and a survey of chief nursing officers. A total of 2,323 RNs from 66 hospitals and 110 critical care units were surveyed across the nation. On average, the RN was 39.5 yrs old (SD = 9.40), had 15.6 yrs (SD = 9.20) experience in health care, and had worked in his or her current position for 8.0 yrs (SD = 7.50). Seventeen percent (n = 391) of the respondents indicated intending to leave their position in the coming year. Of those, 52% (n = 202) reported that the reason was due to working conditions. Organizational climate factors that had an independent effect on intensive care unit nurse intention to leave due to working conditions were professional practice, nurse competence, and tenure (p < .05). Improving professional practice in the work environment and clinical competence of the nurses as well as supporting new hires may reduce turnover and help ensure a stable and qualified workforce.

Influence of boundary conditions on the hydrodynamic forces of an oscillating sphere

NASA Astrophysics Data System (ADS)

Mirauda, Domenica; Negri, Marco; Martinelli, Luca; Malavasi, Stefano

2018-06-01

The design of submerged structures in sea currents presents certain problems that are not only connected to the shape of the obstacle but also to the number of acting forces as well as the correct modelling of the structures dynamic response. Currently, the common approach is that of integrated numerical modelling, which considers the contribution of both current and structure. The reliability of such an approach is better verified with experimental tests performed on models of simple geometry. On the basis of these considerations, the present work analyses the hydrodynamic forces acting on a sphere, which is characterised by a low mass ratio and damping. The sphere is immersed in a free surface flow and can oscillate along the streamwise and transverse flow direction. It is located at three different positions inside the current: close to the channel bottom, near the free surface and in the middle, and equally distant from both the bottom and free surface. The obtained results for different boundaries and flow kinematic conditions show a relevant influence of the free surface on the hydrodynamic forces along both the streamwise and transverse flow directions.

The Independent School Financial Model Is Broken: Here's How We Fix It

ERIC Educational Resources Information Center

Farber, John S.

2012-01-01

All of those who work in independent schools have read a variety of material regarding strategies to improve their financial model. But as the author sees it, in the current economic conditions, there are really only two possible solutions for improving financial structures. They can no longer rely on their traditional strategy of increasing…

Perceptions of Future and Current Teachers on the Organization of Elementary Schools: A Dissonance Approach to the Investigation of Job Satisfaction.

ERIC Educational Resources Information Center

Menon, Maria E.; Christou, Constantinos

2002-01-01

Factor analysis of data from 66 inservice and 79 preservice elementary teachers in Cyprus revealed that future teachers had lower satisfaction with the headmaster's role, school organization, and school climate. Satisfaction with teacher incentives and work conditions was lower for inservice teachers. (Contains 20 references.) (SK)

Research into the Current Plight of Farmworkers in the United States.

ERIC Educational Resources Information Center

Thedinger, Bob

Farmworkers suffer from the same economic and social problems as other poor people but to a greater degree. Among classes of the disadvantaged designated for special Federal attention, only farmworkers are an occupational group. Their plight is unique because it is their working conditions which give rise to most of the other problems endemic to…

Initial Evaluation of the Dermoskeleton Concept: Application of Biomechatronics and Artificial Intelligence to Address the Soldiers Overload Challenge

DTIC Science & Technology

2011-05-01

leg prosthesis for above-the-knee amputees currently commercialized by Ossur hf and developed by Victhom Human Bionics Inc., a medical device...did not feel they worked as hard when wearing the K-SRDTM version POC during the loaded conditions. However, based on our heart rate measured, there

76 FR 2143 - Agency Information Collection Activities: Revision and Extension of a Currently Approved...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-12

... bring foreign workers to the United States on a permanent basis. The information collection consists of..., Administrator, Office of Foreign Labor Certification, U.S. Department of Labor, Room C4312, 200 Constitution Ave... working conditions of U.S. workers similarly employed and that there are not sufficient U.S. workers able...

Pride and confidence at work: potential predictors of occupational health in a hospital setting

PubMed Central

Nilsson, Kerstin; Hertting, Anna; Petterson, Inga-Lill; Theorell, Töres

2005-01-01

Background This study focuses on determinants of a healthy work environment in two departments in a Swedish university hospital. The study is based on previously conducted longitudinal studies at the hospital (1994–2001), concerning working conditions and health outcomes among health care personnel in conjunction with downsizing processes. Overall, there was a general negative trend in relation to mental health, as well as long-term sick leave during the study period. The two departments chosen for the current study differed from the general hospital trend in that they showed stable health development. The aim of the study was to identify and analyse experiential determinants of healthy working conditions. Methods Thematic open-ended interviews were carried out with seventeen managers and key informants, representing different groups of co-workers in the two departments. The interviews were transcribed verbatim and an inductive content analysis was made. Results In the two studied departments the respondents perceived that it was advantageous to belong to a small department, and to work in cooperation-oriented care. The management approaches described by both managers and co-workers could be interpreted as transformational, due to a strain of visionary, delegating, motivating, confirmative, supportive attitudes and a strongly expressed solution-oriented attitude. The daily work included integrated learning activities. The existing organisational conditions, approaches and attitudes promoted tendencies towards a work climate characterised by trust, team spirit and professionalism. In the description of the themes organisational conditions, approaches and climate, two core determinants, work-pride and confidence, for healthy working conditions were interpreted. Our core determinants augment the well-established concepts: manageability, comprehensiveness and meaningfulness. These favourable conditions seem to function as a buffer against the general negative effects of downsizing observed elsewhere in the hospital, and in the literature. Conclusion Research illuminating health-promoting aspects is rather unusual. This study could be seen as explorative. The themes and core dimensions we found could be used as a basis for further intervention studies in similar health-care settings. The result could also be used in future health promotion studies in larger populations. One of the first steps in such a strategy is to formulate relevant questions, and we consider that this study contributes to this. PMID:16137331

Pride and confidence at work: potential predictors of occupational health in a hospital setting.

PubMed

Nilsson, Kerstin; Hertting, Anna; Petterson, Inga-Lill; Theorell, Töres

2005-09-01

This study focuses on determinants of a healthy work environment in two departments in a Swedish university hospital. The study is based on previously conducted longitudinal studies at the hospital (1994-2001), concerning working conditions and health outcomes among health care personnel in conjunction with downsizing processes. Overall, there was a general negative trend in relation to mental health, as well as long-term sick leave during the study period. The two departments chosen for the current study differed from the general hospital trend in that they showed stable health development. The aim of the study was to identify and analyse experiential determinants of healthy working conditions. Thematic open-ended interviews were carried out with seventeen managers and key informants, representing different groups of co-workers in the two departments. The interviews were transcribed verbatim and an inductive content analysis was made. In the two studied departments the respondents perceived that it was advantageous to belong to a small department, and to work in cooperation-oriented care. The management approaches described by both managers and co-workers could be interpreted as transformational, due to a strain of visionary, delegating, motivating, confirmative, supportive attitudes and a strongly expressed solution-oriented attitude. The daily work included integrated learning activities. The existing organisational conditions, approaches and attitudes promoted tendencies towards a work climate characterised by trust, team spirit and professionalism. In the description of the themes organisational conditions, approaches and climate, two core determinants, work-pride and confidence, for healthy working conditions were interpreted. Our core determinants augment the well-established concepts: manageability, comprehensiveness and meaningfulness. These favourable conditions seem to function as a buffer against the general negative effects of downsizing observed elsewhere in the hospital, and in the literature. Research illuminating health-promoting aspects is rather unusual. This study could be seen as explorative. The themes and core dimensions we found could be used as a basis for further intervention studies in similar health-care settings. The result could also be used in future health promotion studies in larger populations. One of the first steps in such a strategy is to formulate relevant questions, and we consider that this study contributes to this.

Comparison of four MPPT techniques for PV systems

NASA Astrophysics Data System (ADS)

Atik, L.; Petit, P.; Sawicki, J. P.; Ternifi, Z. T.; Bachir, G.; Aillerie, M.

2016-07-01

The working behavior of a module / PV array is non-linear and highly dependent on working conditions. As a given condition, there is only one point at which the level of available power at its output is maximum. This point varies with time, enlightenment and temperature. To ensure optimum operation, the use of MPPT control allows us to extract the maximum power. This paper presents a comparative study of four widely-adopted MPPT algorithms, such as Perturb and Observe, Incremental Conductance, Measurements of the variation of the open circuit voltage or of the short-circuit current. Their performance is evaluated using, for all these techniques. In particular, this study compares the behaviors of each technique in presence of solar irradiation variations and temperature fluctuations. These MPPT techniques will be compared using the Matlab / Simulink tool.

Unmet need for disability-related health care services and employment status among adults with disabilities in the Massachusetts Medicaid program.

PubMed

Henry, Alexis D; Long-Bellil, Linda; Zhang, Jianying; Himmelstein, Jay

2011-10-01

The employment rate among adults with disabilities is significantly lower than that among adults without disabilities. Ensuring access to rehabilitative and other health care services may help to address health-related barriers to employment for working-age people with disabilities. This study examined the relationship of unmet need for 6 disability-related health care services to current employment status among working-age adults with disabilities enrolled in the Massachusetts Medicaid (MassHealth Standard) program. Study participants included 436 MassHealth Standard members aged 19 to 64 who responded to the 2005/2006 MassHealth Employment and Disability Survey. Variables included members' demographic characteristics; Medicaid health plan and Medicare enrollment; members' self-report of potentially disabling conditions and current health status; access to health care as well as need and unmet need for 6 specific disability-related health care services (medications, mental health services, substance abuse services, medical supplies, durable medical equipment, personal assistance services); and current employment status. Fifteen percent of members reported currently working. Logistic regression analysis showed that (controlling for demographics, disability, health status, and other factors) members with greater unmet need were significantly less likely to be working (odds ratio = 0.58; 95% confidence interval = 0.33 to 0.99). Members' experience of unmet need was significantly greater for physical health services (supplies, durable medical equipment, personal assistance services) than for behavioral health services (mental health and substance abuse services) or medications. Working members generally rated services as important to work. Approximately 10% to 22% of nonworking members thought they would be able to work if needs were met. Meeting unmet needs for disability-related health care services may result in modest increases in employment among certain working-age adults with disabilities enrolled in the Massachusetts Medicaid program. Copyright © 2011 Elsevier Inc. All rights reserved.

Beam brilliance investigation of high current ion beams at GSI heavy ion accelerator facility.

PubMed

Adonin, A A; Hollinger, R

2014-02-01

In this work the emittance measurements of high current Ta-beam provided by VARIS (Vacuum Arc Ion Source) ion source are presented. Beam brilliance as a function of beam aperture at various extraction conditions is investigated. Influence of electrostatic ion beam compression in post acceleration gap on the beam quality is discussed. Use of different extraction systems (single aperture, 7 holes, and 13 holes) in order to achieve more peaked beam core is considered. The possible ways to increase the beam brilliance are discussed.

Cryogenic gear technology for an orbital transfer vehicle engine and tester design

NASA Technical Reports Server (NTRS)

Calandra, M.; Duncan, G.

1986-01-01

Technology available for gears used in advanced Orbital Transfer Vehicle rocket engines and the design of a cryogenic adapted tester used for evaluating advanced gears are presented. The only high-speed, unlubricated gears currently in cryogenic service are used in the RL10 rocket engine turbomachinery. Advanced rocket engine gear systems experience operational load conditions and rotational speed that are beyond current experience levels. The work under this task consisted of a technology assessment and requirements definition followed by design of a self-contained portable cryogenic adapted gear test rig system.

An Exploration of the Factors Considered When Forming Expectations for Returning to Work following Sickness Absence Due to a Musculoskeletal Condition

PubMed Central

Young, Amanda E.; Choi, YoonSun; Besen, Elyssa

2015-01-01

Introduction Workers’ own expectations for returning to work following a period of sickness absence have been found to be one of the best predictors of future work status; however, there is a limited understanding of why people expect what they do. The current study was undertaken with the aim of determining what people take into consideration when forming their expectations for returning to work. Methods Thirty-four people (8 women, 26 men), who were off work due to a musculoskeletal condition, participated in one of 14 focus groups. Participants were aged 25 to 65 (M = 45, SD = 12.6), and all had been out of work for 3 months or less. Results All participants reported expecting to return to work, with the most common timeframe being approximately 30 days (Range = 1 day-12 months). When explaining what they thought about when forming their expectations, participants referenced numerous considerations. Much of what was spoken about could be compartmentalized to reflect features of themselves, their condition, or their broader environmental contexts. Participant’s subjective experience of these features influenced his or her expectations. Prominent themes included concerns about employability, a desire to get back to normal, no job to go back to, mixed emotions, re-injury concerns, the judgments of workplace stakeholders, being needed by their employer, waiting for input, until the money runs out, and working out what was in their best interest. Conclusions Indications are that many of the reported considerations are amenable to intervention, suggesting opportunities to assist workers in the process of returning to work. PMID:26580559

Novel plasma source for safe beryllium spectral line studies in the presence of beryllium dust

NASA Astrophysics Data System (ADS)

Stankov, B. D.; Vinić, M.; Gavrilović Božović, M. R.; Ivković, M.

2018-05-01

Plasma source for beryllium spectral line studies in the presence of beryllium dust particles was realised. The guideline during construction was to prevent exposure to formed dust, considering the toxicity of beryllium. Plasma source characterization through determination of optimal working conditions is described. The necessary conditions for Be spectral line appearance and optimal conditions for line shape measurements are found. It is proven experimentally that under these conditions dust appears coincidently with the second current maximum. The electron density measured after discharge current maximum is determined from the peak separation of the hydrogen Balmer beta spectral line, and the electron temperature is determined from the ratios of the relative intensities of Be spectral lines emitted from successive ionized stages of atoms. Maximum values of electron density and temperature are measured to be 9.3 × 1022 m-3 and 16 800 K, respectively. Construction details and testing of the BeO discharge tube in comparison with SiO2 and Al2O3 discharge tubes are also presented in this paper.

A concurrent multiscale micromorphic molecular dynamics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Shaofan, E-mail: shaofan@berkeley.edu; Tong, Qi

2015-04-21

In this work, we have derived a multiscale micromorphic molecular dynamics (MMMD) from first principle to extend the (Andersen)-Parrinello-Rahman molecular dynamics to mesoscale and continuum scale. The multiscale micromorphic molecular dynamics is a con-current three-scale dynamics that couples a fine scale molecular dynamics, a mesoscale micromorphic dynamics, and a macroscale nonlocal particle dynamics together. By choosing proper statistical closure conditions, we have shown that the original Andersen-Parrinello-Rahman molecular dynamics is the homogeneous and equilibrium case of the proposed multiscale micromorphic molecular dynamics. In specific, we have shown that the Andersen-Parrinello-Rahman molecular dynamics can be rigorously formulated and justified from firstmore » principle, and its general inhomogeneous case, i.e., the three scale con-current multiscale micromorphic molecular dynamics can take into account of macroscale continuum mechanics boundary condition without the limitation of atomistic boundary condition or periodic boundary conditions. The discovered multiscale scale structure and the corresponding multiscale dynamics reveal a seamless transition from atomistic scale to continuum scale and the intrinsic coupling mechanism among them based on first principle formulation.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fertig, Fabian, E-mail: fabian.fertig@ise.fraunhofer.de; Greulich, Johannes; Rein, Stefan

Spatially resolved determination of solar cell parameters is beneficial for loss analysis and optimization of conversion efficiency. One key parameter that has been challenging to access by an imaging technique on solar cell level is short-circuit current density. This work discusses the robustness of a recently suggested approach to determine short-circuit current density spatially resolved based on a series of lock-in thermography images and options for a simplified image acquisition procedure. For an accurate result, one or two emissivity-corrected illuminated lock-in thermography images and one dark lock-in thermography image have to be recorded. The dark lock-in thermography image can bemore » omitted if local shunts are negligible. Furthermore, it is shown that omitting the correction of lock-in thermography images for local emissivity variations only leads to minor distortions for standard silicon solar cells. Hence, adequate acquisition of one image only is sufficient to generate a meaningful map of short-circuit current density. Beyond that, this work illustrates the underlying physics of the recently proposed method and demonstrates its robustness concerning varying excitation conditions and locally increased series resistance. Experimentally gained short-circuit current density images are validated for monochromatic illumination in comparison to the reference method of light-beam induced current.« less

Preliminary Work for Modeling the Propellers of an Aircraft as a Noise Source in an Acoustic Boundary Element Analysis

NASA Technical Reports Server (NTRS)

Vlahopoulos, Nickolas; Lyle, Karen H.; Burley, Casey L.

1998-01-01

An algorithm for generating appropriate velocity boundary conditions for an acoustic boundary element analysis from the kinematics of an operating propeller is presented. It constitutes the initial phase of Integrating sophisticated rotorcraft models into a conventional boundary element analysis. Currently, the pressure field is computed by a linear approximation. An initial validation of the developed process was performed by comparing numerical results to test data for the external acoustic pressure on the surface of a tilt-rotor aircraft for one flight condition.

The Physician-Patient Working Alliance in Hemodialysis Treatment.

PubMed

Fuertes, Jairo N; Rubinstein, Sofia; Reyes, Mariela; Iampornpipopchai, Pichet; Mujeeb, Shanza; Smith, Carroll R; Toporovsky, Arielle

2017-01-01

Over the past 20 years, the role of psychological and social factors, including the physician-patient working alliance, have emerged as integral components of medical care for patients with a myriad of health conditions. The current study examines a model comprised of psychological-interpersonal factors and the extent to which it explains patient satisfaction with and adherence to hemodialysis treatment. One hundred and seven adults with end-stage renal disease who were receiving regular outpatient hemodialysis participated in the study. Path analyses show that the physician-patient working alliance indirectly predicts patient adherence through patient satisfaction and patients' outcome expectations. The working alliance directly predicts patients' quality of life. It is concluded that consistent with previous research, the physician-patient working alliance is a significant factor in predicting key patient behaviors in medical care.

Effects of Amplitude Variations on Deformation and Damage Evolution in SnAgCu Solder in Isothermal Cycling

NASA Astrophysics Data System (ADS)

Wentlent, Luke; Alghoul, Thaer M.; Greene, Christopher M.; Borgesen, Peter

2018-02-01

Although apparently simpler than in thermal cycling, the behavior of SnAgCu (SAC) solder joints in cyclic bending or vibration is not currently well understood. The rate of damage has been shown to scale with the inelastic work per cycle, and excursions to higher amplitudes lead to an apparent softening, some of which remains so that damage accumulation is faster in subsequent cycling at lower amplitudes. This frequently leads to a dramatic breakdown of current damage accumulation rules. An empirical damage accumulation rule has been proposed to account for this, but any applicability to the extrapolation of accelerated test results to life under realistic long-term service conditions remains to be validated. This will require a better understanding of the underlying mechanisms. The present work provides experimental evidence to support recent suggestions that the observed behavior is a result of cycling-induced dislocation structures providing for increased diffusion creep. It is argued that this means that the measured work is an indicator of the instantaneous dislocation density, rather than necessarily reflecting the actual work involved in the creation of the damage.

New technology in turbine aerodynamics

NASA Technical Reports Server (NTRS)

Glassman, A. J.; Moffitt, T. P.

1972-01-01

A cursory review is presented of some of the recent work that has been done in turbine aerodynamic research at NASA-Lewis Research Center. Topics discussed include the aerodynamic effect of turbine coolant, high work-factor (ratio of stage work to square of blade speed) turbines, and computer methods for turbine design and performance prediction. An extensive bibliography is included. Experimental cooled-turbine aerodynamics programs using two-dimensional cascades, full annular cascades, and cold rotating turbine stage tests are discussed with some typical results presented. Analytically predicted results for cooled blade performance are compared to experimental results. The problems and some of the current programs associated with the use of very high work factors for fan-drive turbines of high-bypass-ratio engines are discussed. Turbines currently being investigated make use of advanced blading concepts designed to maintain high efficiency under conditions of high aerodynamic loading. Computer programs have been developed for turbine design-point performance, off-design performance, supersonic blade profile design, and the calculation of channel velocities for subsonic and transonic flow fields. The use of these programs for the design and analysis of axial and radial turbines is discussed.

Studies in High Current Density Ion Sources for Heavy Ion Fusion Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chacon-Golcher, Edwin

This dissertation develops diverse research on small (diameter ~ few mm), high current density (J ~ several tens of mA/cm 2) heavy ion sources. The research has been developed in the context of a programmatic interest within the Heavy Ion Fusion (HIF) Program to explore alternative architectures in the beam injection systems that use the merging of small, bright beams. An ion gun was designed and built for these experiments. Results of average current density yield () at different operating conditions are presented for K + and Cs + contact ionization sources and potassium aluminum silicate sources. Maximum valuesmore » for a K + beam of ~90 mA/cm 2 were observed in 2.3 μs pulses. Measurements of beam intensity profiles and emittances are included. Measurements of neutral particle desorption are presented at different operating conditions which lead to a better understanding of the underlying atomic diffusion processes that determine the lifetime of the emitter. Estimates of diffusion times consistent with measurements are presented, as well as estimates of maximum repetition rates achievable. Diverse studies performed on the composition and preparation of alkali aluminosilicate ion sources are also presented. In addition, this work includes preliminary work carried out exploring the viability of an argon plasma ion source and a bismuth metal vapor vacuum arc (MEVVA) ion source. For the former ion source, fast rise-times (~ 1 μs), high current densities (~ 100 mA/cm +) and low operating pressures (< 2 mtorr) were verified. For the latter, high but acceptable levels of beam emittance were measured (ε n ≤ 0.006 π· mm · mrad) although measured currents differed from the desired ones (I ~ 5mA) by about a factor of 10.« less

Criminalisation of clients: reproducing vulnerabilities for violence and poor health among street-based sex workers in Canada—a qualitative study

PubMed Central

Krüsi, A; Pacey, K; Bird, L; Taylor, C; Chettiar, J; Allan, S; Bennett, D; Montaner, J S; Kerr, T; Shannon, K

2014-01-01

Objectives To explore how criminalisation and policing of sex buyers (clients) rather than sex workers shapes sex workers’ working conditions and sexual transactions including risk of violence and HIV/sexually transmitted infections (STIs). Design Qualitative and ethnographic study triangulated with sex work-related violence prevalence data and publicly available police statistics. Setting Vancouver, Canada, provides a unique opportunity to evaluate the impact of policies that criminalise clients as the local police department adopted a sex work enforcement policy in January 2013 that prioritises sex workers’ safety over arrest, while continuing to target clients. Participants 26 cisgender and 5 transgender women who were street-based sex workers (n=31) participated in semistructured interviews about their working conditions. All had exchanged sex for money in the previous 30 days in Vancouver. Outcome measures Thematic analysis of interview transcripts and ethnographic field notes focused on how police enforcement of clients shaped sex workers’ working conditions and sexual transactions, including risk of violence and HIV/STIs, over an 11-month period postpolicy implementation (January–November 2013). Results Sex workers’ narratives and ethnographic observations indicated that while police sustained a high level of visibility, they eased charging or arresting sex workers and showed increased concern for their safety. However, participants’ accounts and police statistics indicated continued police enforcement of clients. This profoundly impacted the safety strategies sex workers employed. Sex workers continued to mistrust police, had to rush screening clients and were displaced to outlying areas with increased risks of violence, including being forced to engage in unprotected sex. Conclusions These findings suggest that criminalisation and policing strategies that target clients reproduce the harms created by the criminalisation of sex work, in particular, vulnerability to violence and HIV/STIs. The current findings support decriminalisation of sex work to ensure work conditions that support the health and safety of sex workers in Canada and globally. PMID:24889853

Photoelectrochemistry of III-V epitaxial layers and nanowires for solar energy conversion

NASA Astrophysics Data System (ADS)

Parameshwaran, Vijay; Enck, Ryan; Chung, Roy; Kelley, Stephen; Sampath, Anand; Reed, Meredith; Xu, Xiaoqing; Clemens, Bruce

2017-05-01

III-V materials, which exhibit high absorption coefficients and charge carrier mobility, are ideal templates for solar energy conversion applications. This work describes the photoelectrochemistry research in several IIIV/electrolyte junctions as an enabler for device design for solar chemical reactions. By designing lattice-matched epitaxial growth of InGaP and GaP on GaAs and Si, respectively, extended depletion region electrodes achieve photovoltages which provide an additional boost to the underlying substrate photovoltage. The InGaP/GaAs and GaP/Si electrodes drive hydrogen evolution currents under aqueous conditions. By using nanowires of InN and InP under carefully controlled growth conditions, current and capacitance measurements are obtained to reveal the nature of the nanowire-electrolyte interface and how light is translated into photocurrent for InP and a photovoltage in InN. The materials system is expanded into the III-V nitride semiconductors, in which it is shown that varying the morphology of GaN on silicon yields insights to how the interface and light conversion is modulated as a basis for future designs. Current extensions of this work address growth and tuning of the III-V nitride electrodes with doping and polarization engineering for efficient coupling to solar-driven chemical reactions, and rapid-throughput methods for III-V nanomaterials synthesis in this materials space.

Electrical Characterization of Critical Phase Change Conditions in Nanoscale Ge2Sb2Te5 Pillars

NASA Astrophysics Data System (ADS)

Ozatay, Ozhan; Stipe, Barry; Katine, Jordan; Terris, Bruce

2008-03-01

Following the original work of Ovshinsky on disordered semiconductors that exhibit ovonic threshold switching (OTS) there has been substantial interest in the electronic reversible switching properties of chalcogenides^1. The current induced phase transitions between polycrystalline and amorphous states in these materials offer orders of magnitude changes in the conductance which makes them an ideal candidate for non-volatile data storage applications. In this work we investigate the scaling of critical programming conditions required to observe such transitions between highly resistive (disordered) and highly conductive (ordered) states by constructing a resistance map with various pulse widths and amplitudes under different cooling conditions (as a function of pulse trailing edge). We study the evolution of critical phase change conditions as a function of contact size (50nm-1μm) and shape (circle-square-rectangle). We compare the resulting switching behaviour with the predictions of a finite-element model of the electro-thermal physics to analyze the nature of the switching dynamics at the nanoscale. ^1 S-H. Lee, Y. Jung, R. Agarwal, Nature Nanotechnology; doi:10:1038/nnano.2007.291

Quantification of the Conditioning Phase in Cooled Pixelated TlBr Detectors

NASA Astrophysics Data System (ADS)

Koehler, Will; He, Zhong; O'Neal, Sean; Yang, Hao; Kim, Hadong; Cirignano, Leonard; Shah, Kanai

2015-08-01

Thallium-bromide (TlBr) is currently under investigation as an alternative room-temperature semiconductor gamma-ray spectrometer due to its favorable material properties (large bandgap, high atomic numbers, and high density). Previous work has shown that 5 mm thick pixelated TlBr detectors can achieve sub-1% FWHM energy resolution at 662 keV for single-pixel events. These results are limited to - 20° C operation where detector performance is stable. During the first one to five days of applied bias at - 20° C, many TlBr detectors undergo a conditioning phase, where the energy resolution improves and the depth-dependent electron drift velocity stabilizes. In this work, the spectroscopic performance, drift velocity, and freed electron concentrations of multiple 5 mm thick pixelated TlBr detectors are monitored throughout the conditioning phase. Additionally, conditioning is performed twice on the same detector at different times to show that improvement mechanisms relax when the detector is stored without bias. We conclude that the improved spectroscopy results from internal electric field stabilization and uniformity caused by fewer trapped electrons.

Proof-of-Concept Testing of the Passive Cooling System (T-CLIP™) for Solar Thermal Applications at an Elevated Temperature

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Seung Jun; Quintana, Donald L.; Vigil, Gabrielle M.

2015-11-30

The Applied Engineering and Technology-1 group (AET-1) at Los Alamos National Laboratory (LANL) conducted the proof-of-concept tests of SolarSPOT LLC’s solar thermal Temperature- Clipper, or T-CLIP™ under controlled thermal conditions using a thermal conditioning unit (TCU) and a custom made environmental chamber. The passive T-CLIP™ is a plumbing apparatus that attaches to a solar thermal collector to limit working fluid temperature and to prevent overheating, since overheating may lead to various accident scenarios. The goal of the current research was to evaluate the ability of the T-CLIP™ to control the working fluid temperature by using its passive cooling mechanism (i.e.more » thermosiphon, or natural circulation) in a small-scale solar thermal system. The assembled environmental chamber that is thermally controlled with the TCU allows one to simulate the various possible weather conditions, which the solar system will encounter. The performance of the T-CLIP™ was tested at two different target temperatures: 1) room temperature (70 °F) and 2) an elevated temperature (130 °F). The current test campaign demonstrated that the T-CLIP™ was able to prevent overheating by thermosiphon induced cooling in a small-scale solar thermal system. This is an important safety feature in situations where the pump is turned off due to malfunction or power outages.« less

Implementation of early intensive behavioural intervention for children with autism in Switzerland.

PubMed

Studer, Nadja; Gundelfinger, Ronnie; Schenker, Tanja; Steinhausen, Hans-Christoph

2017-01-21

There is a major gap between the US and most European countries regarding the implementation of early intensive behavioural intervention (EIBI) for children with autism. The present paper reports on the current status of EIBI in Switzerland and on the effectiveness of EIBI under clinical conditions in a Swiss pilot project. The paper combines a narrative report of the care system for children with autism in Switzerland and an initial evaluation of EIBI as implemented in the Department of Child and Adolescent Psychiatry, University of Zurich. The current situation of the implementation of EIBI for children with autism in Switzerland is characterized by marked deficits in its acceptance. Major reasons include insufficient governmental approval and lacking legal and financial support. In addition, ignorance among health care providers and educational professionals has contributed to this situation precluding that children with autism receive the most beneficial assistance. The authors have initiated and been working in an intervention centre offering EIBI for a decade and report on their experience with the implementation of EIBI. Based on their clinical practice, they document that EIBI also works efficiently under ordinary mental health service conditions. EIBI needs to be implemented more intensively in Switzerland. Although the effects of EIBI as implemented in Zurich are promising, the results are not as pronounced as under controlled research conditions.

The work-based predictors of job engagement and job satisfaction experienced by community health professionals.

PubMed

Noblet, Andrew J; Allisey, Amanda F; Nielsen, Ingrid L; Cotton, Stacey; LaMontagne, Anthony D; Page, Kathryn M

Job engagement represents a critical resource for community-based health care agencies to achieve high levels of effectiveness. However, studies examining the organizational sources of job engagement among health care professionals have generally overlooked those workers based in community settings. This study drew on the demand-control model, in addition to stressors that are more specific to community health services (e.g., unrewarding management practices), to identify conditions that are closely associated with the engagement experienced by a community health workforce. Job satisfaction was also included as a way of assessing how the predictors of job engagement differ from those associated with other job attitudes. Health and allied health care professionals (n = 516) from two Australian community health services took part in the current investigation. Responses from the two organizations were pooled and analyzed using linear multiple regression. The analyses revealed that three working conditions were predictive of both job engagement and job satisfaction (i.e., job control, quantitative demands, and unrewarding management practices). There was some evidence of differential effects with cognitive demands being associated with job engagement, but not job satisfaction. The results provide important insights into the working conditions that, if addressed, could play key roles in building a more engaged and satisfied community health workforce. Furthermore, working conditions like job control and management practices are amenable to change and thus represent important areas where community health services could enhance the energetic and motivational resources of their employees.

Vitamin-D Deficiency As a Potential Environmental Risk Factor in Multiple Sclerosis, Schizophrenia, and Autism.

PubMed

Kočovská, Eva; Gaughran, Fiona; Krivoy, Amir; Meier, Ute-Christiane

2017-01-01

In this short review, we want to summarize the current findings on the role of vitamin-D in multiple sclerosis (MS), schizophrenia, and autism. Many studies have highlighted hypovitaminosis-D as a potential environmental risk factor for a variety of conditions such as MS, asthma, cardiovascular disease, and, more recently, psychiatric diseases. However, whether hypovitaminosis-D is a potential causative factor for the development or activity in these conditions or whether hypovitaminosis-D may be due to increased vitamin-D consumption by an activated immune system (reverse causation) is the focus of intense research. Here, we will discuss current evidence exploring the role of vitamin-D in MS, schizophrenia, and autism and its impact on adaptive and innate immunity, antimicrobial defense, the microbiome, neuroinflammation, behavior, and neurogenesis. More work is needed to gain insight into its role in the underlying pathophysiology of these conditions as it may offer attractive means of intervention and prevention.

Amplifiers dedicated for large area SiC photodiodes

NASA Astrophysics Data System (ADS)

Doroz, P.; Duk, M.; Korwin-Pawlowski, M. L.; Borecki, M.

2016-09-01

Large area SiC photodiodes find applications in optoelectronic sensors working at special conditions. These conditions include detection of UV radiation in harsh environment. Moreover, the mentioned sensors have to be selective and resistant to unwanted signals. For this purpose, the modulation of light at source unit and the rejection of constant current and low frequency component of signal at detector unit are used. The popular frequency used for modulation in such sensor is 1kHz. The large area photodiodes are characterized by a large capacitance and low shunt resistance that varies with polarization of the photodiode and can significantly modify the conditions of signal pre-amplification. In this paper two pre-amplifiers topology are analyzed: the transimpedance amplifier and the non-inverting voltage to voltage amplifier with negative feedback. The feedback loops of both pre-amplifiers are equipped with elements used for initial constant current and low frequency signals rejections. Both circuits are analyzed and compared using simulation and experimental approaches.

Precommitting to Serve the Underserved

PubMed Central

Eyal, Nir; Bärnighausen, Till

2014-01-01

In many countries worldwide, especially in Sub-Saharan Africa, a shortage of physicians limits the provision of lifesaving interventions. One existing strategy to increase the number of physicians in areas of critical shortage is conditioning medical school scholarships on a precommitment to work in medically underserved areas later. Current practice is usually to demand only one year of service for each year of funded studies. We show the effectiveness of scholarships conditional on such precommitment for increasing physician supplies in underserved areas. Then we defend these scholarships against ethical worries that they constitute slavery contracts; rely on involuntary, biased, or unauthorized early consent by a young signatory; put excessive strains on signed commitments; give rise to domination; and raise suspicion of slavery contracts. Importantly, we find that scholarships involving far longer commitment than current practice allows would also withstand these worries. Policymakers should consider introducing conditional scholarships, including long-term versions, as a means to increasing the supply of physicians to medically underserved areas. PMID:22548519

Precommitting to serve the underserved.

PubMed

Eyal, Nir; Bärnighausen, Till

2012-01-01

In many countries worldwide, especially in sub-Saharan Africa, a shortage of physicians limits the provision of lifesaving interventions. One existing strategy to increase the number of physicians in areas of critical shortage is conditioning medical school scholarships on a precommitment to work in medically underserved areas later. Current practice is usually to demand only one year of service for each year of funded studies. We show the effectiveness of scholarships conditional on such precommitment for increasing physician supplies in underserved areas. Then we defend these scholarships against ethical worries that they constitute slavery contracts; rely on involuntary, biased, or unauthorized early consent by a young signatory; put excessive strains on signed commitments; give rise to domination; and raise suspicion of slavery contracts. Importantly, we find that scholarships involving far longer commitment than current practice allows would also withstand these worries. Policymakers should consider introducing conditional scholarships, including long-term versions, as a means to increasing the supply of physicians to medically underserved areas.

Fuse Selection for the Two-Stage Explosive Type Switches

NASA Astrophysics Data System (ADS)

Muravlev, I. O.; Surkov, M. A.; Tarasov, E. V.; Uvarov, N. F.

2017-04-01

In the two-level explosive switch destruction of a delay happens in the form of electric explosion. Criteria of similarity of electric explosion in transformer oil are defined. The challenge of protecting the power electrical equipment from short circuit currents is still urgent, especially with the growth of unit capacity. Is required to reduce the tripping time as much as possible, and limit the amplitude of the fault current, that is very important for saving of working capacity of life-support systems. This is particularly important when operating in remote stand-alone power supply systems with a high share of renewable energy, working through the inverter transducers, as well as inverter-type diesel generators. The explosive breakers copes well with these requirements. High-speed flow of transformer oil and high pressure provides formation rate of a contact gap of 20 - 100 m/s. In these conditions there is as a rapid increase in voltage on the discontinuity, and recovery of electric strength (Ures) after current interruption.

Current phase relation from graphs and diagrams and application to thick ferromagnetic Josephson junctions

NASA Astrophysics Data System (ADS)

Margaris, I.; Paltoglou, V.; Flytzanis, N.

2018-05-01

In this work we present a method of representing terms in the current-phase-relation of a ballistic Josephson junction by combinations of diagrams, used in previous work to represent an equivalent of the matching condition determinant of the junction. This is accomplished by the expansion of the logarithm of this determinant in Taylor series and keeping track of surviving terms, i.e. terms that do not annihilate each other. The types of the surviving terms are represented by connected graphs, whose points represent diagrammatic terms of the determinant expansion. Then the theory is applied to obtain approximations of the current-phase relation of relatively thick ballistic ferromagnetic Josephson junctions with non-collinear magnetizations. This demonstrates the versatility of the method in developing approximations schemes and providing physical insight into the nature of contributions to the supercurrent from the available particle excitations in the junction. We also discuss the strong second harmonic contribution to the supercurrent in junctions with three mutually orthogonal magnetization vectors and a weak intermediate ferromagnet.

[International migration, health, and work: an analysis of Haitians in Mato Grosso State, Brazil].

PubMed

Leão, Luís Henrique da Costa; Muraro, Ana Paula; Palos, Cássia Carraco; Martins, Maria Angela C; Borges, Fabiano Tonaco

2017-07-27

This article addresses the relations between immigration, health, and work in Haitian immigrants in Cuiabá and Várzea Grande, Mato Grosso State, Brazil, emphasizing their work conditions. This was an exploratory study based on primary data collected through a survey of the Haitian population in Cuiabá in 2014-2015. A total of 452 Haitians were interviewed, living in Cuiabá and Várzea Grande (373 men and 79 women), and the findings point to the precarious social situation of Haitian immigrants in Mato Grosso State, marked by high unemployment. Of the immigrants interviewed, 52.7% were currently working and 26.5% reported a workweek greater than 48 hours. The two main occupations for Haitian immigrants in Cuiabá were construction and services, and most were working below their original level of training, skills sets, and job experience in Haiti. The main risks identified in these two sectors were physical (53.2% and 63.4%, respectively) and accidents (23.4% and 17.1%, respectively), in addition to reports of physical and psychosocial distress. The study points to the precarious social, economic, and labor conditions of the Haitian population in the capital of Mato Grosso.

Digital mapping in extreme and remote environments

NASA Astrophysics Data System (ADS)

Andersson, Joel; Bauer, Tobias; Sarlus, Zimer; Zainy, Maher; Brethes, Anais

2017-04-01

During the last few years, Luleå University of Technology has performed a series of research projects in remote areas with extreme climatic conditions using digital mapping technologies. The majority of past and ongoing research projects focus on the arctic regions of the Fennoscandian Shield and Greenland but also on the Zagros fold-and-thrust belt in northern Iraq. Currently, we use the Midland Valley application FieldMove on iPad mini devices with ruggedized casings. As all projects have a strong focus on geological field work, harsh climatic conditions are a challenge not only for the geologists but also for the digital mapping hardware. In the arctic regions especially cold temperatures affect battery lifetime and performance of the screens. But also high temperatures are restricting digital mapping. From experience, a typical temperature range where digital mapping, using iPad tablets, is possible lies between -20 and +40 degrees. Furthermore, the remote character of field areas complicates access but also availability of electricity. By a combination of robust solar chargers and ruggedized batteries we are able to work entirely autarkical. Additionally, we are currently installing a drone system that allows us to map outcrops normally inaccessible because of safety reasons or time deficiency. The produced data will subsequently be taken into our Virtual Reality studio for interpretation and processing. There we will be able to work also with high resolution DEM data from Lidar scanning allowing us to interpret structural features such as post-glacial faults in areas that are otherwise only accessible by helicopter. By combining digital field mapping with drone technique and a Virtual Reality studio we are able to work in hardly accessible areas, improve safety during field work and increase efficiency substantially.

A new modified listening span task to enhance validity of working memory assessment for people with and without aphasia.

PubMed

Ivanova, Maria V; Hallowell, Brooke

2014-01-01

Deficits in working memory (WM) are an important subset of cognitive processing deficits associated with aphasia. However, there are serious limitations to research on WM in aphasia largely due to the lack of an established valid measure of WM impairment for this population. The aim of the current study was to address shortcomings of previous measures by developing and empirically evaluating a novel WM task with a sentence-picture matching processing component designed to circumvent confounds inherent in existing measures of WM in aphasia. The novel WM task was presented to persons with (n=27) and without (n=33) aphasia. Results demonstrated high concurrent validity of a novel WM task. Individuals with aphasia performed significantly worse on all conditions of the WM task compared to individuals without aphasia. Different patterns of performance across conditions were observed for the two groups. Additionally, WM capacity was significantly related to auditory comprehension abilities in individuals with mild aphasia but not those with moderate aphasia. Strengths of the novel WM task are that it allows for differential control for length versus complexity of verbal stimuli and indexing of the relative influence of each, minimizes metalinguistic requirements, enables control for complexity of processing components, allows participants to respond with simple gestures or verbally, and eliminates reading requirements. Results support the feasibility and validity of using a novel task to assess WM in individuals with and without aphasia. Readers will be able to (1) discuss the limitations of current working memory measures for individuals with aphasia; (2) describe how task design features of a new working memory task for people with aphasia address shortcomings of existing measures; (3) summarize the evidence supporting the validity of the novel working memory task. Copyright © 2014 Elsevier Inc. All rights reserved.

The AAS Working Group on Accessibility and Disability (WGAD): progress, current projects, and prospects for making astronomy accessible to all

NASA Astrophysics Data System (ADS)

Aarnio, Alicia; Diaz-Merced, Wanda; Monkiewicz, Jacqueline; Knierman, Karen; AAS WGAD

2018-01-01

Representation of astronomers with disabilities is low at the earliest career stages and losses compound with career stage thereafter; single-digit and lower percentage representation statistics are in large part due to systemic barriers to access and failure to accommodate the needs of users of a wide range of abilities. In this presentation, we discuss the barriers currently inhibiting broad access to astronomical publications, databases, and conferences. The WGAD was formed in January of 2016 to work toward removal of these barriers to make our field inclusive of astronomers with disabilities at all career stages. We have productively engaged with publishers and accessibility audits have been performed. Database accessibility evaluation is underway, and we are working with the AAS and other professional organizations on conference accessibility. We are keeping users centrally focused via surveys and user test groups, and holding paramount the overarching idea that meeting present accessibility standards is a necessary but insufficient condition for full access.

Development of Eddy Current Techniques for Detection of Deep Fatigue Cracks in Multi-Layer Airframe Components

NASA Technical Reports Server (NTRS)

Wincheski, Russell A.

2008-01-01

Thick, multi-layer aluminum structure has been widely used in aircraft design in critical wing splice areas. The multi-layer structure generally consists of three or four aluminum layers with different geometry and varying thickness, which are held together with fasteners. The detection of cracks under fasteners with ultrasonic techniques in subsurface layers away from the skin is impeded primarily by interlayer bonds and faying sealant condition. Further, assessment of such sealant condition is extremely challenging in terms of complexity of structure, limited access, and inspection cost. Although Eddy current techniques can be applied on in-service aircraft from the exterior of the skin without knowing sealant condition, the current eddy current techniques are not able to detect defects with wanted sensitivity. In this work a series of low frequency eddy current probes have been designed, fabricated and tested for this application. A probe design incorporating a shielded magnetic field sensor concentrically located in the interior of a drive coil has been employed to enable a localized deep diffusion of the electromagnetic field into the part under test. Due to the required low frequency inspections, probes have been testing using a variety of magnetic field sensors (pickup coil, giant magneto-resistive, anisotropic magneto-resistive, and spin-dependent tunneling). The probe designs as well as capabilities based upon a target inspection for sub-layer cracking in an airframe wing spar joint is presented.

Verification of the technical parameters of head-only electrical stunning of pigs under commercial conditions.

PubMed

Végh, Akos; Abonyi-Tóth, Zsolt; Rafai, Pál

2010-06-01

The European Food Safety Authority recommends a minimum current of 1.3 Amps for the electrical head-only stunning of pigs. However, it is stated as well that 'the technical reference data for head-only electrical stunning of pigs such as 1.3 Amps are either rather old or worked out under experimental laboratory conditions'. This study was carried out to verify the electrical parameters of pig stunning under commercial conditions. Altogether 145 fattener pigs (body weight range: 30-150 kg, median 109 kg) were tested at four different private slaughterhouses in Hungary where head-only electrical stunners were used with different constant voltage settings. In each case the following data were recorded: individual liveweight (kg), current (A) and voltage (V) (measured with an individually developed analogue device placed in the circuit), current duration (s), effectiveness of stunning, grading of carcass. Correlations between these parameters and effectiveness were examined. Besides that, any correlation between the test parameters and impedance of head was examined. In 128 out of the 145 cases the stunning was effective (88.3%). Effectiveness was significantly related to current but not to other parameters such as voltage and duration of load. Impedance of head was not correlated with the size of the animal and the meat grading scores. Generally, it was concluded that the use of a single electrical parameter (e.g. a minimum current of 1.3 A) as a prerequisite of good stunning is not ideal.

Expatriates' Multiple Fears, from Terrorism to Working Conditions: Development of a Model.

PubMed

Giorgi, Gabriele; Montani, Francesco; Fiz-Perez, Javier; Arcangeli, Giulio; Mucci, Nicola

2016-01-01

Companies' internationalization appears to be fundamental in the current globalized and competitive environment and seems important not only for organizational success, but also for societal development and sustainability. On one hand, global business increases the demand for managers for international assignment. On the other hand, emergent fears, such as terrorism, seem to be developing around the world, enhancing the risk of expatriates' potential health problems. The purpose of this paper is to examine the relationships between the emergent concept of fear of expatriation with further workplace fears (economic crisis and dangerous working conditions) and with mental health problems. The study uses a quantitative design. Self-reported data were collected from 265 Italian expatriate workers assigned to both Italian and worldwide projects. Structural equation model analyses showed that fear of expatriation mediates the relationship of mental health with fear of economic crisis and with perceived dangerous working conditions. As expected, in addition to fear, worries of expatriation are also related to further fears. Although, the study is based on self-reports and the cross-sectional study design limits the possibility of making causal inferences, the new constructs introduced add to previous research.

Expatriates’ Multiple Fears, from Terrorism to Working Conditions: Development of a Model

PubMed Central

Giorgi, Gabriele; Montani, Francesco; Fiz-Perez, Javier; Arcangeli, Giulio; Mucci, Nicola

2016-01-01

Companies’ internationalization appears to be fundamental in the current globalized and competitive environment and seems important not only for organizational success, but also for societal development and sustainability. On one hand, global business increases the demand for managers for international assignment. On the other hand, emergent fears, such as terrorism, seem to be developing around the world, enhancing the risk of expatriates’ potential health problems. The purpose of this paper is to examine the relationships between the emergent concept of fear of expatriation with further workplace fears (economic crisis and dangerous working conditions) and with mental health problems. The study uses a quantitative design. Self-reported data were collected from 265 Italian expatriate workers assigned to both Italian and worldwide projects. Structural equation model analyses showed that fear of expatriation mediates the relationship of mental health with fear of economic crisis and with perceived dangerous working conditions. As expected, in addition to fear, worries of expatriation are also related to further fears. Although, the study is based on self-reports and the cross-sectional study design limits the possibility of making causal inferences, the new constructs introduced add to previous research. PMID:27790173

Quantitative investigation of hydraulic mixing energy input during batch mode anaerobic digestion and its impact on performance.

PubMed

McLeod, James; Othman, Maazuza Z; Parthasarathy, Rajarathinam

2018-05-26

The relationship between mixing energy input and biogas production was investigated by anaerobically digesting sewage sludge in lab scale, hydraulically mixed, batch mode digesters at six different specific energy inputs. The goal was to identify how mixing energy influenced digestion performance at quantitative levels to help explain the varying results in other published works. The results showed that digester homogeneity was largely uninfluenced by energy input, whereas cumulative biogas production and solids destruction were. With similar solids distributions between conditions, the observed differences were attributed to shear forces disrupting substrate-microbe flocs rather than the formation of temperature and/or concentration gradients. Disruption of the substrate-microbe flocs produced less favourable conditions for hydrolytic bacteria, resulting in less production of biomass and more biogas. Overall, this hypothesis explains the current body of research including the inhibitory conditions reported at extreme mixing power inputs. However, further work is required to definitively prove it. Copyright © 2018 Elsevier Ltd. All rights reserved.

Situational Leadership in Air Traffic Control

NASA Technical Reports Server (NTRS)

Arvidsson, Marcus; Johansson, Curt R.; Ek, Asa; Akselsson, Roland

2007-01-01

In high-risk environments such as air traffic control, leadership on different levels plays a certain role in establishing, promoting, and maintaining a good safety culture. The current study aimed to investigate how leadership styles, leadership style adaptability, and over and under task leadership behavior differed across situations, operative conditions, leadership structures, and working tasks in an air traffic control setting. Study locations were two air traffic control centers in Sweden with different operational conditions and leadership structures, and an administrative air traffic management unit. Leadership was measured with a questionnaire based on Leader Effectiveness and Adaptability Description (LEAD; Blanchard, Zigarmi & Zigarmi, 2003; Hersey & Blanchard, 1988). The results showed that the situation had strong impact on the leadership in which the leadership behavior was more relationship oriented in Success and Group situations than in Hardship and Individual situations. The leadership adaptability was further superior in Success and Individual situations compared with Hardship and Group situations. Operational conditions, leadership structures and working tasks were, on the other hand, not associated with leadership behavior.

Brief encounters: what do primary care professionals contribute to peoples' self-care support network for long-term conditions? A mixed methods study.

PubMed

Rogers, Anne; Vassilev, Ivaylo; Brooks, Helen; Kennedy, Anne; Blickem, Christian

2016-02-17

Primary care professionals are presumed to play a central role in delivering long-term condition management. However the value of their contribution relative to other sources of support in the life worlds of patients has been less acknowledged. Here we explore the value of primary care professionals in people's personal communities of support for long-term condition management. A mixed methods survey with nested qualitative study designed to identify relationships and social network member's (SNM) contributions to the support work of managing a long-term condition conducted in 2010 in the North West of England. Through engagement with a concentric circles diagram three hundred participants identified 2544 network members who contributed to illness management. The results demonstrated how primary care professionals are involved relative to others in ongoing self-care management. Primary care professionals constituted 15.5 % of overall network members involved in chronic illness work. Their contribution was identified as being related to illness specific work providing less in terms of emotional work than close family members or pets and little to everyday work. The qualitative accounts suggested that primary care professionals are valued mainly for access to medication and nurses for informational and monitoring activities. Overall primary care is perceived as providing less input in terms of extended self-management support than the current literature on policy and practice suggests. Thus primary care professionals can be described as providing 'minimally provided support'. This sense of a 'minimally' provided input reinforces limited expectations and value about what primary care professionals can provide in terms of support for long-term condition management. Primary care was perceived as having an essential but limited role in making a contribution to support work for long-term conditions. This coalesces with evidence of a restricted capacity of primary care to take on the work load of self-management support work. There is a need to prioritise exploring the means by which extended self-care support could be enhanced out-with primary care. Central to this is building a system capable of engaging network capacity to mobilise resources for self-management support from open settings and the broader community.

The Development of Duct for a Horizontal Axis Turbine Using CFD

NASA Astrophysics Data System (ADS)

Ghani, Mohamad Pauzi Abdul; Yaacob, Omar; Aziz, Azliza Abdul

2010-06-01

Malaysia is heavily dependent on the fossil fuels to satisfy its energy demand. Nowadays, renewable energy which has attracted great interest is marine current energy, which extracted by a device called a device called marine current turbine. This energy resource has agreat potential to be exploited on a large scale because of its predictability and intensity. This paper will focus on developing a Horizontal Axis Marine Current Turbine (HAMCT) rotor to extract marine current energy suitable for Malaysian sea conditions. This work incorporates the characteristic of Malaysia's ocean of shallow water and low speed current in developing the turbines. The HAMCT rotor will be developed and simulated using CAD and CFD software for various combination of inlet and oulet duct design. The computer simulation results of the HAMCT being developed will be presented.

Sterile working in ultrasonography: the use of dedicated ultrasound covers and sterile ultrasound gel.

PubMed

Marhofer, Peter; Fritsch, Gerhard

2015-01-01

Ultrasound is currently an important tool for diagnostic and interventional procedures. Ultrasound imaging provides significant advantages as compared to other imaging methods. The widespread use of ultrasound also carries the risk of drawbacks such as cross-infections. A large body of literature reports this possibly life-threatening side effect and specific patient populations are particularly at risk (e.g., neonates). Various methods of ultrasound probe disinfection are described; however, none of the mechanical or chemical probe disinfection procedures is optimal and, in particular, disinfection with high concentration of alcohol might be associated with ultrasound probe damage. The preparation of ultrasound probes with dedicated probe covers is a useful alternative for sterile working conditions. One ultrasound probe cover discussed in this paper is directly glued on to the ultrasound probe without the use of ultrasound coupling gel. By the use of sterile ultrasound coupling gel at the outer surface, additional effects on aseptic working conditions can be obtained.

78. Augmenting NMDA Receptor Signaling Enhances Working Memory and Alters Gamma Oscillations in Patients With Schizophrenia

PubMed Central

Forsyth, Jennifer; Bachman, Peter; Asarnow, Robert

2017-01-01

Abstract Background: Gamma band oscillations (30–80 Hz) are associated with numerous sensory and higher cognitive functions and are abnormal in patients with schizophrenia. Glutamate signaling at the N-methyl-D-aspartate receptor (NMDAR) is theorized to play a key role in the pathophysiology of schizophrenia and NMDAR antagonists disrupt working memory and gamma oscillations in healthy individuals. It has therefore been suggested that NMDAR dysfunction may contribute to abnormalities in gamma oscillations and working memory in schizophrenia. In the current study, we examined the effects of acutely augmenting NMDAR signaling using the NMDAR agonist, d-cycloserine (DCS), on working memory and gamma power in patients with schizophrenia. Methods: In a double-blind design, patients with schizophrenia were randomized to receive a single dose of 100 mg DCS (SZ-DCS; n = 24) or Placebo (SZ-PLC; n = 21). Patients completed a spatial n-back task involving a 0-back control condition and 1-back and 2-back working memory loads while undergoing EEG recording. Gamma power (30–80 Hz) during the 0-back condition assessed gamma power associated with basic perceptual, motor, and attentive processes. Change in gamma power for correct working memory trials relative to the 0-back condition assessed gamma power associated with working memory function. Results: Among patients who performed above chance (SZ-DCS = 17, SZ-PLC = 16), patients who received DCS showed superior working memory performance compared to patients who received Placebo. Gamma power during the 0-back control condition was similar between SZ-DCS and SZ-PLC who performed above chance. However, gamma power associated with working memory function was significantly suppressed in SZ-DCS compared to SZ-PLC, particularly over frontal right channels. In addition, whereas higher working memory gamma power over frontal right channels was associated with better working memory performance in SZ-PLC, this relationship was not evident in SZ-DCS. Conclusion: Results suggest that augmenting NMDAR signaling enhanced working memory performance and suppressed gamma activity associated with working memory function in patients with schizophrenia. Given prior reports that schizophrenia patients may utilize excessive gamma power for successful working memory performance, these findings suggest that augmenting NMDAR signaling may improve the efficiency of neural encoding for successful working memory function in schizophrenia.

3D magnetohydrodynamic modelling of a dc low-current plasma arc batch reactor at very high pressure in helium

NASA Astrophysics Data System (ADS)

Lebouvier, A.; Iwarere, S. A.; Ramjugernath, D.; Fulcheri, L.

2013-04-01

This paper deals with a three-dimensional (3D) time-dependent magnetohydrodynamic (MHD) model under peculiar conditions of very high pressures (from 2 MPa up to 10 MPa) and low currents (<1 A). Studies on plasma arc working under these unusual conditions remain almost unexplored because of the technical and technological challenges to develop a reactor able to sustain a plasma at very high pressures. The combined effect of plasma reactivity and high pressure would probably open the way towards new promising applications in various fields: chemistry, lightning, materials or nanomaterial synthesis. A MHD model helps one to understand the complex and coupled phenomena surrounding the plasma which cannot be understood by simply experimentation. The model also provides data which are difficult to directly determine experimentally. The model simulates an experimental-based batch reactor working with helium. The particular reactor in question was used to investigate the Fischer-Tropsch application, fluorocarbon production and CO2 retro-conversion. However, as a first approach in terms of MHD, the model considers the case for helium as a non-reactive working gas. After a detailed presentation of the model, a reference case has been fully analysed (P = 8 MPa, I = 0.35 A) in terms of physical properties. The results show a bending of the arc and displacement of the anodic arc root towards the top of the reactor, due to the combined effects of convection, gravity and electromagnetic forces. A parametric study on the pressure (2-10 MPa) and current (0.25-0.4 A) was then investigated. The operating pressure does not show an influence on the contraction of the arc but higher pressures involve a higher natural convection in the reactor, driven by the density gradients between the cold and hot gas.

Improving Best Air Conditioner Efficiency by 20-30% through a High Efficiency Fan and Diffuser Stage Coupled with an Evaporative Condenser Pre-Cooler

DOE Office of Scientific and Technical Information (OSTI.GOV)

Parker, Danny S; Sherwin, John R; Raustad, Richard

2014-04-10

The Florida Solar Energy Center (FSEC) conducted a research project to improve the best residential air conditioner condenser technology currently available on the market by retrofitting a commercially-available unit with both a high efficiency fan system and an evaporative pre-cooler. The objective was to integrate these two concepts to achieve an ultra-efficient residential air conditioner design. The project produced a working prototype that was 30% more efficient compared to the best currently-available technologies; the peak the energy efficiency ratio (EER) was improved by 41%. Efficiency at the Air-Conditioning and Refrigeration Institute (ARI) standard B-condition which is used to estimate seasonalmore » energy efficiency ratio (SEER), was raised from a nominal 21 Btu/Wh to 32 Btu/Wh.« less

Photovoltaic Plasma Interaction Test 2

NASA Technical Reports Server (NTRS)

Kaufman, Bradford A.; Chrulski, Daniel; Myers, Roger M.

1996-01-01

The International Space Station (ISS) program is developing a plasma contactor to mitigate the harmful effects of charge collection on the station's large photovoltaic arrays. The purpose of the present test was to examine the effects of charge collection on the solar array electrical circuit and to verify the effectiveness of the plasma contactor. The results showed that the plasma contactor was able to eliminate structure arcing for any array output voltage. However, the current requirements of the plasma contactor were higher than those for prior testing and predicted by analysis. Three possible causes for this excess current demand are discussed. The most likely appeared to be a high local pressure on or very near the surface of the array as a result of vacuum tank conditions. Therefore, in actual space conditions, the plasma contactor should work as predicted.

The effects of hydrogen embrittlement by cathodic protection on the CTOD of buried natural gas pipeline

NASA Astrophysics Data System (ADS)

Kim, Cheol-man; Kim, Woo-sik; Kho, Young-tai

2002-04-01

For the corrosion protection of natural gas transmission pipelines, two methods are used, cathodic protection and a coating technique. In the case of cathodic protection, defects are embrittled by hydrogen occurring at crack tips or surfaces of materials. It is, however, very important to evaluate whether cracks in the embrittled area can grow or not, especially in weld metal. In this work, on the basis of elastic plastic fracture mechanics, we performed CTOD testing under various test conditions, such as potential and current density. The CTOD of the base steel and weld metal showed a strong dependence on the test conditions. The CTOD decreased with increasing cathodic potential and current density. The morphology of the fracture surface showed quasi-cleavage. Cathodic overprotection results in hydrogen embrittlement at the crack tip.

A review of protocols for monitoring streams and juvenile fish in forested regions of the Pacific Northwest.

Treesearch

Scott A. Stolnack; Mason D. Bryant; Robert C. Wissmar

2005-01-01

This document reviews existing and proposed protocols used to monitor stream ecosystem conditions and responses to land management activities in the Pacific Northwest. Because of recent work aimed at improving the utility of habitat survey and fish abundance assessment methods, this review focuses on current (since 1993) monitoring efforts that assess stream habitat...

The Curriculum Debate: Why It Is Important Today. IBE Working Papers on Curriculum Issues No. 10

ERIC Educational Resources Information Center

Tedesco, Juan Carlos; Opertti, Renato; Amadio, Massimo

2013-01-01

The current debates on the purpose and role of education are linked to social imaginaries which should be convening and achievable. At the core of these imaginaries is the construction of a more just society. Increasingly, education is viewed as a necessary condition for such visions to be achievable. However, this situation is concomitant with…

Non-cooperative Brownian donkeys: A solvable 1D model

NASA Astrophysics Data System (ADS)

Jiménez de Cisneros, B.; Reimann, P.; Parrondo, J. M. R.

2003-12-01

A paradigmatic 1D model for Brownian motion in a spatially symmetric, periodic system is tackled analytically. Upon application of an external static force F the system's response is an average current which is positive for F < 0 and negative for F > 0 (absolute negative mobility). Under suitable conditions, the system approaches 100% efficiency when working against the external force F.

Special Education Teacher Evaluation: Why It Matters, What Makes It Challenging, and How to Address These Challenges

ERIC Educational Resources Information Center

Johnson, Evelyn; Semmelroth, Carrie Lisa

2014-01-01

There is currently little consensus on how special education teachers should be evaluated. The lack of consensus may be due to several reasons. Special education teachers work under a variety of complex conditions, with a very heterogeneous population, and support student progress toward a very individualized set of goals. In addition, special…

The Effectiveness of Interventions to Address Childhood Asthma: A Scan of the Literature and Current Approaches. MDRC Working Paper

ERIC Educational Resources Information Center

Lee, Helen; McCullough, Colleen

2016-01-01

Asthma is the leading chronic health condition among children in the United States and a major cause of childhood disability. It also disproportionately affects low-income and racial and ethnic minorities. Although a wide range of interventions have been implemented to improve asthma-related outcomes among socioeconomically disadvantaged and…

A comparison of the adaptations of strains of Lymantria dispar multiple nucleopolyhedrovirus to hosts from spatially isolated populations

Treesearch

V.V. Martemyanov; J.D. Podgwaite; I.A. Belousova; S.V. Pavlushin; J.M. Slavicek; O.A. Baturina; M.R. Kabilov; A.V. Ilyinykh

2017-01-01

The adaptation of pathogens to either their hosts or to environmental conditions is the focus of many current ecological studies. In this work we compared the ability of six spatially-distant Lymantria dispar (gypsy moth) multiple nucleopolyhedrovirus (LdMNPV) strains (three from eastern North America and three from central Asia) to induce acute...

The impact of nurse empowerment on job satisfaction.

PubMed

Ning, Sun; Zhong, He; Libo, Wang; Qiujie, Li

2009-12-01

This paper is a report of a study conducted to test Kanter's organizational empowerment theoretical model specifying the relationships among demographics, structural empowerment, and job satisfaction. Empowerment has become an increasingly important factor in determining nurses' job satisfaction in current restructured work environments in China. A correlational, cross-sectional design was used to test Kanter's organizational empowerment model with a sample of 650 full-time nurses employed in six Chinese hospitals in 2007, with a response rate of 92% (n = 598). The instruments used were the Demographic Data Questionnaire, Conditions of Work Effectiveness Questionnaire-II, and Job Satisfaction Scale. The three lowest scoring items for Conditions of Work Effectiveness Questionnaire-II were resources, opportunity and informal power. The job satisfaction items revealing most dissatisfaction were workload and compensation, professional promotion, amount of work responsibility, work environments, and organizational policies. A statistically significant positive correlation was found between empowerment and job satisfaction (r = 0.547, P < 0.01). The demographic factors influencing empowerment were work objectives and age. The influencing factors for job satisfaction were work objectives and education level. The results provide support for Kanter's organizational empowerment theory in the Chinese nurse population. Nurses who view their work environments as empowering are more likely to provide high quality care. Enhancing empowerment in a supportive environment would allow nurses to experience satisfaction with their jobs.

[Workflow involving preventive health care promotes the economic development of a company].

PubMed

Braun, M

2003-12-01

Today's working society obviously develops from industrial production to knowledge-intensive service. In service-oriented working conditions, the importance of the human being as a main performer of economic success increases. Thus, the development leads to a changing spectrum of occupational health risks. Together with socio-demographic developments, individual strain-oriented health disorders connected to one's occupation might endanger an enterprise's capacity of performance and innovation as well as its sustainable enterprise development. Only healthy, motivated and qualified employees are able and ready to keep their creative and customer-oriented potential harnessed and thereby work to the best of their ability. Consequently, occupational health gains a more important role within the enterprise. Although in many enterprises the benefit contribution of preventive work design has not yet been considered that relevant, enterprises have realised that a preventive health-oriented work design might help to better manage current business challenges. An up-to-date definition of health includes the goals of health improvement, personality development as well as a comprehensive well-being. Health is a prerequisite and result of a productive reflection upon the conditions and challenges of work. Business practice shows that a preventive work design should involve an economic benefit for the enterprise. If occupational health is seen as a characteristic of quality and a prerequisite for sustainable enterprise development, economic potentials of preventive work designs will expand considerably.

Does the chronic care model meet the emerging needs of people living with multimorbidity? A systematic review and thematic synthesis

PubMed Central

Abu Dabrh, Abd Moain; Gionfriddo, Michael R.; Erwin, Patricia; Montori, Victor M.

2018-01-01

Background The Chronic Care Model (CCM) emerged in the 1990s as an approach to re-organize primary care and implement critical elements that enable it to proactively attend to patients with chronic conditions. The chronic care landscape has evolved further, as most patients now present with multiple chronic conditions and increasing psychosocial complexity. These patients face accumulating and overwhelming complexity resulting from the sum of uncoordinated responses to each of their problems. Minimally Disruptive Medicine (MDM) was proposed to respond to this challenge, aiming at improving outcomes that matter to patients with the smallest burden of treatment. We sought to critically appraise the extent to which MDM constructs (e.g., reducing patient work, improving patients’ capacity) have been adopted within CCM implementations. Methods We conducted a systematic review and qualitative thematic synthesis of reports of CCM implementations published from 2011–2016. Results CCM implementations were mostly aligned with the healthcare system’s goals, condition-specific, and targeted disease-specific outcomes or healthcare utilization. No CCM implementation addressed patient work. Few reduced treatment workload without adding additional tasks. Implementations supported patient capacity by offering information, but rarely offered practical resources (e.g., financial assistance, transportation), helped patients reframe their biography with chronic illness, or assisted them in engaging with a supportive social network. Few implementations aimed at improving functional status or quality of life, and only one-third of studies were targeted for patients of low socioeconomic status. Conclusion MDM provides a lens to operationalize how to care for patients with multiple chronic conditions, but its constructs remain mostly absent from how implementations of the CCM are currently reported. Improvements to the primary care of patients with multimorbidity may benefit from the application of MDM, and the current CCM implementations that do apply MDM constructs should be considered exemplars for future implementation work. PMID:29420543

Advanced image collection, information extraction, and change detection in support of NN-20 broad area search and analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Petrie, G.M.; Perry, E.M.; Kirkham, R.R.

1997-09-01

This report describes the work performed at the Pacific Northwest National Laboratory (PNNL) for the U.S. Department of Energy`s Office of Nonproliferation and National Security, Office of Research and Development (NN-20). The work supports the NN-20 Broad Area Search and Analysis, a program initiated by NN-20 to improve the detection and classification of undeclared weapons facilities. Ongoing PNNL research activities are described in three main components: image collection, information processing, and change analysis. The Multispectral Airborne Imaging System, which was developed to collect georeferenced imagery in the visible through infrared regions of the spectrum, and flown on a light aircraftmore » platform, will supply current land use conditions. The image information extraction software (dynamic clustering and end-member extraction) uses imagery, like the multispectral data collected by the PNNL multispectral system, to efficiently generate landcover information. The advanced change detection uses a priori (benchmark) information, current landcover conditions, and user-supplied rules to rank suspect areas by probable risk of undeclared facilities or proliferation activities. These components, both separately and combined, provide important tools for improving the detection of undeclared facilities.« less

You make me tired: An experimental test of the role of interpersonal operant conditioning in fatigue.

PubMed

Lenaert, Bert; Jansen, Rebecca; van Heugten, Caroline M

2018-04-01

Chronic fatigue is highly prevalent in the general population as well as in multiple chronic diseases and psychiatric disorders. Its etiology however remains poorly understood and cannot be explained by biological factors alone. Occurring in a psychosocial context, the experience and communication of fatigue may be shaped by social interactions. In particular, interpersonal operant conditioning may strengthen and perpetuate fatigue complaints. In this experiment, individuals (N = 44) repeatedly rated their currently experienced fatigue while engaging in cognitive effort (working memory task). Subtle social reward was given when fatigue increased relative to the previous rating; or disapproval when fatigue decreased. In the control condition, only neutral feedback was given. Although all participants became more fatigued during cognitive effort, interpersonal operant conditioning led to increased fatigue reporting relative to neutral feedback. This effect occurred independently of conscious awareness. Interestingly, the experimental condition also performed worse on the working memory task. Results suggest that fatigue complaints (and cognitive performance) may become controlled by their consequences such as social reward, and not exclusively by their antecedents such as effort. Results have implications for treatment development and suggest that interpersonal operant conditioning may contribute to fatigue becoming a chronic symptom. Copyright © 2018 Elsevier Ltd. All rights reserved.

Analytical expression for the tunnel current through the redox-mediated tunneling contact in the case of the adiabatic electron transfer at one of the working electrodes and any possible type of the electron transfer at the other electrode

NASA Astrophysics Data System (ADS)

Medvedev, Igor G.

2017-11-01

We study the tunnel current through a one-level redox molecule immersed into the electrolyte solution for the case when the coupling of the molecule to one of the working electrodes is strong while it is arbitrary to the other electrode. Using the Feynman-Vernon influence functional theory and the perturbation expansion of the effective action of the classical oscillator coupled both to the valence level of the redox molecule and to the thermal bath representing the classical fluctuations of the polarization of the solvent, we obtain, following the canonical way, the Langevin equation for the oscillator. It is found that for the aqueous electrolyte solution, the damping and the stochastic forces which arise due to the tunnel current are much smaller than those due to the thermal bath and therefore can be neglected. We estimate the higher-order corrections to the effective action and show that the Langevin dynamics takes place in this case for arbitrary parameters of the tunneling junction under the condition of the strong coupling of the redox molecule to one of the working electrodes. Then the steady-state coordinate distribution function of the oscillator resulting from the corresponding Fokker-Planck equation is the Boltzmann distribution function which is determined by the adiabatic free energy surface arising from the mean current-induced force. It enables us to obtain the expression for the tunnel current in the case when the coupling of the redox molecule to one of the working electrodes is strong while it is arbitrary to the other electrode.

Analytical expression for the tunnel current through the redox-mediated tunneling contact in the case of the adiabatic electron transfer at one of the working electrodes and any possible type of the electron transfer at the other electrode.

PubMed

Medvedev, Igor G

2017-11-21

We study the tunnel current through a one-level redox molecule immersed into the electrolyte solution for the case when the coupling of the molecule to one of the working electrodes is strong while it is arbitrary to the other electrode. Using the Feynman-Vernon influence functional theory and the perturbation expansion of the effective action of the classical oscillator coupled both to the valence level of the redox molecule and to the thermal bath representing the classical fluctuations of the polarization of the solvent, we obtain, following the canonical way, the Langevin equation for the oscillator. It is found that for the aqueous electrolyte solution, the damping and the stochastic forces which arise due to the tunnel current are much smaller than those due to the thermal bath and therefore can be neglected. We estimate the higher-order corrections to the effective action and show that the Langevin dynamics takes place in this case for arbitrary parameters of the tunneling junction under the condition of the strong coupling of the redox molecule to one of the working electrodes. Then the steady-state coordinate distribution function of the oscillator resulting from the corresponding Fokker-Planck equation is the Boltzmann distribution function which is determined by the adiabatic free energy surface arising from the mean current-induced force. It enables us to obtain the expression for the tunnel current in the case when the coupling of the redox molecule to one of the working electrodes is strong while it is arbitrary to the other electrode.

Finite-deformation phase-field chemomechanics for multiphase, multicomponent solids

NASA Astrophysics Data System (ADS)

Svendsen, Bob; Shanthraj, Pratheek; Raabe, Dierk

2018-03-01

The purpose of this work is the development of a framework for the formulation of geometrically non-linear inelastic chemomechanical models for a mixture of multiple chemical components diffusing among multiple transforming solid phases. The focus here is on general model formulation. No specific model or application is pursued in this work. To this end, basic balance and constitutive relations from non-equilibrium thermodynamics and continuum mixture theory are combined with a phase-field-based description of multicomponent solid phases and their interfaces. Solid phase modeling is based in particular on a chemomechanical free energy and stress relaxation via the evolution of phase-specific concentration fields, order-parameter fields (e.g., related to chemical ordering, structural ordering, or defects), and local internal variables. At the mixture level, differences or contrasts in phase composition and phase local deformation in phase interface regions are treated as mixture internal variables. In this context, various phase interface models are considered. In the equilibrium limit, phase contrasts in composition and local deformation in the phase interface region are determined via bulk energy minimization. On the chemical side, the equilibrium limit of the current model formulation reduces to a multicomponent, multiphase, generalization of existing two-phase binary alloy interface equilibrium conditions (e.g., KKS). On the mechanical side, the equilibrium limit of one interface model considered represents a multiphase generalization of Reuss-Sachs conditions from mechanical homogenization theory. Analogously, other interface models considered represent generalizations of interface equilibrium conditions consistent with laminate and sharp-interface theory. In the last part of the work, selected existing models are formulated within the current framework as special cases and discussed in detail.

Theoretical analysis of shock induced depolarization and current generation in ferroelectrics

NASA Astrophysics Data System (ADS)

Agrawal, Vinamra; Bhattacharya, Kaushik

Ferroelectric generators are used to generate large magnitude current pulse by impacting a polarized ferroelectric material. The impact causes depolarization of the material and at high impact speeds, dielectric breakdown. Depending on the loading conditions and the electromechanical boundary conditions, the current or voltage profiles obtained vary. In this study, we explore the large deformation dynamic response of a ferroelectric material. Using the Maxwell's equations, conservation laws and the second law of thermodynamics, we derive the governing equations for the phase boundary propagation as well as the driving force acting on it. We allow for the phase boundary to contain surface charges which introduces the contribution of curvature of phase boundary in the governing equations and the driving force. This type of analysis accounts for the dielectric breakdown and resulting conduction in the material. Next, we implement the equations derived to solve a one dimensional impact problem on a ferroelectric material under different electrical boundary conditions. The constitutive law is chosen to be piecewise quadratic in polarization and quadratic in the strain. We solve for the current profile generated in short circuit case and for voltage profile in open circuited case. This work was made possible by the financial support of the US Air Force Office of Scientific Research through the Center of Excellence in High Rate Deformation Physics of Heterogeneous Materials (Grant: FA 9550-12-1-0091).

Impact of different environmental conditions on lithium-ion batteries performance through the thermal monitoring with fiber sensors

NASA Astrophysics Data System (ADS)

Nascimento, Micael; Ferreira, Marta S.; Pinto, João. L.

2017-08-01

In this work, an optical fiber sensing network has been developed to assess the impact of different environmental conditions on lithium batteries performance through the real time thermal monitoring. The battery is submitted to constant current charge and different discharge C-rates, under normal and abusive operating conditions. The results show that for the discharge C-rate of 5.77C, the LiB under cold and dry climates had 32.5% and 27.2% lower temperature variations, when compared with temperate climates, respectively. The higher temperature shift detected in the temperate climate was related to the battery better performance regarding discharge capacity and power capabilities.

Reliability and Characteristics of Wafer-Level Chip-Scale Packages under Current Stress

NASA Astrophysics Data System (ADS)

Chen, Po-Ying; Kung, Heng-Yu; Lai, Yi-Shao; Hsiung Tsai, Ming; Yeh, Wen-Kuan

2008-02-01

In this work, we present a novel approach and method for elucidating the characteristics of wafer-level chip-scale packages (WLCSPs) for electromigration (EM) tests. The die in WLCSP was directly attached to the substrate via a soldered interconnect. The shrinking of the area of the die that is available for power, and the solder bump also shrinks the volume and increases the density of electrons for interconnect efficiency. The bump current density now approaches to 106 A/cm2, at which point the EM becomes a significant reliability issue. As known, the EM failure depends on numerous factors, including the working temperature and the under bump metallization (UBM) thickness. A new interconnection geometry is adopted extensively with moderate success in overcoming larger mismatches between the displacements of components during current and temperature changes. Both environments and testing parameters for WLCSP are increasingly demanded. Although failure mechanisms are considered to have been eliminated or at least made manageable, new package technologies are again challenging its process, integrity and reliability. WLCSP technology was developed to eliminate the need for encapsulation to ensure compatibility with smart-mount technology (SMT). The package has good handing properties but is now facing serious reliability problems. In this work, we investigated the reliability of a WLCSP subjected to different accelerated current stressing conditions at a fixed ambient temperature of 125 °C. A very strong correlation exists between the mean time to failure (MTTF) of the WLCSP test vehicle and the mean current density that is carried by a solder joint. A series of current densities were applied to the WLCSP architecture; Black's power law was employed in a failure mode simulation. Additionally, scanning electron microscopy (SEM) was adopted to determine the differences existing between high- and low-current-density failure modes.

Presynaptic miniature GABAergic currents in developing interneurons.

PubMed

Trigo, Federico F; Bouhours, Brice; Rostaing, Philippe; Papageorgiou, George; Corrie, John E T; Triller, Antoine; Ogden, David; Marty, Alain

2010-04-29

Miniature synaptic currents have long been known to represent random transmitter release under resting conditions, but much remains to be learned about their nature and function in central synapses. In this work, we describe a new class of miniature currents ("preminis") that arise by the autocrine activation of axonal receptors following random vesicular release. Preminis are prominent in gabaergic synapses made by cerebellar interneurons during the development of the molecular layer. Unlike ordinary miniature postsynaptic currents in the same cells, premini frequencies are strongly enhanced by subthreshold depolarization, suggesting that the membrane depolarization they produce belongs to a feedback loop regulating neurotransmitter release. Thus, preminis could guide the formation of the interneuron network by enhancing neurotransmitter release at recently formed synaptic contacts. Copyright 2010 Elsevier Inc. All rights reserved.

Integration methods for thermosensitive gel systems in garments

NASA Astrophysics Data System (ADS)

Reich, A.; Rödel, H.; Stoll, A.; Liske, A.; Zehm, D.

2017-10-01

Humans live and work under severe thermophysiological conditions, which are characterized by extreme temperatures and humidities. Furthermore, additional burdens can arise from physical activities of the human body or the work conditions (resulting in psychological stress) [1]. The thermoregulation of the human body compensates such situations and maintains the core body temperature at 37°C (98,6 °F). The currently used systems for supporting human thermoregulation, such as PCM-equipped surface structures or mobile water-based cooling units have the disadvantage that the running cooling process is neither switchable nor reversible. Another promising possibility for a personal cooling is the use of temperature-dependent superabsorbers (so-called LCST and UCST) in garments, which absorb the human sweat and transmit it to the environment by evaporation. Cooling during evaporation results in heat transfer from the human body.

Comparison of four MPPT techniques for PV systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Atik, L., E-mail: lotfi.atik@univ-usto.dz; Ternifi, Z. T.; Université de Lorraine, LMOPS, EA 4423, 57070 Metz

2016-07-25

The working behavior of a module / PV array is non-linear and highly dependent on working conditions. As a given condition, there is only one point at which the level of available power at its output is maximum. This point varies with time, enlightenment and temperature. To ensure optimum operation, the use of MPPT control allows us to extract the maximum power. This paper presents a comparative study of four widely-adopted MPPT algorithms, such as Perturb and Observe, Incremental Conductance, Measurements of the variation of the open circuit voltage or of the short-circuit current. Their performance is evaluated using, formore » all these techniques. In particular, this study compares the behaviors of each technique in presence of solar irradiation variations and temperature fluctuations. These MPPT techniques will be compared using the Matlab / Simulink tool.« less

A randomised controlled trial investigating the benefits of adaptive working memory training for working memory capacity and attentional control in high worriers.

PubMed

Hotton, Matthew; Derakshan, Nazanin; Fox, Elaine

2018-01-01

The process of worry has been associated with reductions in working memory capacity and availability of resources necessary for efficient attentional control. This, in turn, can lead to escalating worry. Recent investigations into working memory training have shown improvements in attentional control and cognitive performance in high trait-anxious individuals and individuals with sub-clinical depression. The current randomised controlled trial investigated the effects of 15 days of adaptive n-back working memory training, or an active control task, on working memory capacity, attentional control and worry in a sample of high worriers. Pre-training, post-training and one-month follow-up measures of working memory capacity were assessed using a Change Detection task, while a Flanker task was used to assess attentional control. A breathing focus task was used as a behavioural measure of worry in addition to a number of self-report assessments of worry and anxiety. Overall there was no difference between the active training and the active control condition with both groups demonstrating similar improvements in working memory capacity and worry, post-training and at follow-up. However, training-related improvements on the n-back task were associated with gains in working memory capacity and reductions in worry symptoms in the active training condition. These results highlight the need for further research investigating the role of individual differences in working memory training. Copyright © 2017. Published by Elsevier Ltd.

Professional development themes in strength and conditioning coaches.

PubMed

Tod, David A; Bond, Kath A; Lavallee, David

2012-03-01

The purpose of this study was to explore professional development themes in experienced strength and conditioning coaches. Strength and conditioning coaches (N = 15, mean age = 34.3 years, SD = 5.2 years) with 11.4 (SD = 4.9) years experience working with elite, professional, or talented athletes were interviewed about their professional development. The interviews were transcribed verbatim and content analyzed. Over time, subjects' service-delivery practices became more flexible and client driven. Their role understanding also broadened to include various dimensions, such as the need to consider various stakeholders and the value of good relationships with athletes. The subjects shifted from relying on external justification for professional decision making to their experience-based knowledge. The subjects believed athlete work experience, interactions with senior strength and conditioning coaches and other colleagues, the professional literature, and nonprofessional experiences, such as their own athletic experience and sales or managerial training, were the primary influences on their professional development. Typically, the subjects experienced anxiety about their competence, both early in their careers and when working in new contexts or with new athlete groups, but over time, they developed increased confidence. In addition, the subjects experienced reduced narcissism over time about the control they had over athletes and their competitive results. The current results provide information about the characteristics of effective strength and conditioning coaches, the ways they develop their competencies to help athletes, and the emotions they experience throughout their careers. These results may help strength and conditioning practitioners in planning and optimizing their professional development and effectiveness with athletes.

Development of software to improve AC power quality on large spacecraft

NASA Technical Reports Server (NTRS)

Kraft, L. Alan

1991-01-01

To insure the reliability of a 20 kHz, alternating current (AC) power system on spacecraft, it is essential to analyze its behavior under many adverse operating conditions. Some of these conditions include overloads, short circuits, switching surges, and harmonic distortions. Harmonic distortions can become a serious problem. It can cause malfunctions in equipment that the power system is supplying, and, during distortions such as voltage resonance, it can cause equipment and insulation failures due to the extreme peak voltages. To address the harmonic distortion issue, work was begun under the 1990 NASA-ASEE Summer Faculty Fellowship Program. Software, originally developed by EPRI, called HARMFLO, a power flow program capable of analyzing harmonic conditions on three phase, balanced, 60 Hz AC power systems, was modified to analyze single phase, 20 kHz, AC power systems. Since almost all of the equipment used on spacecraft power systems is electrically different from equipment used on terrestrial power systems, it was also necessary to develop mathematical models for the equipment to be used on the spacecraft. The modelling was also started under the same fellowship work period. Details of the modifications and models completed during the 1990 NASA-ASEE Summer Faculty Fellowship Program can be found in a project report. As a continuation of the work to develop a complete package necessary for the full analysis of spacecraft AC power system behavior, deployment work has continued through NASA Grant NAG3-1254. This report details the work covered by the above mentioned grant.

[Aging of the working population in the European Union].

PubMed

Ilmarinen, J; Costa, G

2000-01-01

The working population over 50 years of age will grow considerably during the next 15 years. After 2010, the number of retired people over 65 years of age will be almost double that of 1995, with a strong impact also on working conditions and the labour market. Work ability is a dynamic process that changes, through its components, throughout life and is the result of the interaction between individual resources (including health, functional capacity, education and skills), working conditions, and the surrounding society. Work ability creates the basis for the employability of an individual, which can be supported by a number of actions (e.g. legislation on work and retirement) and social attitudes (e.g. age discrimination). Consequently, the prevalence of limitations in work ability varies significantly according to how it is evaluated and the frequency of work disability can vary considerably in different times, locations and populations. The Work Ability Index, created and used in a Finnish 11-year longitudinal study, has been proved a useful practical tool for the assessment of workers' fitness and a good predictor of work disability. Measures able to restore, maintain or promote work ability depend on the current work status and the needs of the target groups, and must concentrate on work content, physical work environment and the work community. The actions targeted towards the individual, on the other hand, concentrate on strengthening the health status and functional resources of the workers and developing professional expertise and skills. Correctly targeted and integrated measures improve work ability of ageing workers and therefore lead to improved work quality, increased productivity and also improved quality of life and well-being. They also have positive long-term effects on the "third age", when the worker retires.

Reluctant entrepreneurs: musicians and entrepreneurship in the 'new' music industry.

PubMed

Haynes, Jo; Marshall, Lee

2018-06-01

Changing labour conditions in the creative industries - with celebrations of autonomy and entrepreneurialism intertwined with increasing job insecurity, portfolio careers and short-term, project-based contracts - are often interpreted as heralding changes to employment relations more broadly. The position of musicians' labour in relation to these changes is unclear, however, given that these kinds of conditions have defined musicians' working practices over much longer periods of time (though they may have intensified due to well-documented changes to the music industry brought about by digitization and disintermediation). Musicians may thus be something of a barometer of current trends, as implied in the way that the musically derived label 'gig economy' is being used to describe the spread of precarious working conditions to broader sections of the population. This article, drawing on original qualitative research that investigated the working practices of musicians, explores one specific aspect of these conditions: whether musicians are self-consciously entrepreneurial towards their work and audience. We found that, while the musicians in our study are routinely involved in activities that could be construed as entrepreneurial, generally they were reluctant to label themselves as entrepreneurs. In part this reflected understandings of entrepreneurialism as driven by profit-seeking but it also reflected awareness that being a popular musician has always involved business and commercial dimensions. Drawing on theoretical conceptions of entrepreneurship developed by Joseph Schumpeter we highlight how the figure of the entrepreneur and the artist/musician share much in common and reflect various aspects of romantic individualism. Despite this, there are also some notable differences and we conclude that framing musicians' labour as entrepreneurial misrepresents their activities through an overemphasis on the economic dimensions of their work at the expense of the cultural. © The Author 2017.

Working conditions of female part-time and full-time teachers in relation to health status.

PubMed

Seibt, Reingard; Matz, Annerose; Hegewald, Janice; Spitzer, Silvia

2012-08-01

Teacher's volume of employment and health status are controversially discussed in the current literature. This study focused on female teachers with part-time versus full-time jobs in association with working conditions and health status depending on age. A sample of 263 part-time and 367 full-time female teachers (average age 46.7 ± 7.8 vs. 46.0 ± 6.3) participated in an occupational health screening. Specific work conditions, stressors (job history-questionnaire) and effort-reward-imbalance ratio (ERI-Q) were measured and their relationships to mental and physical health were analysed. Health status was quantified by complaints (BFB questionnaire), general mental health status (GHQ-12) and cardiovascular risk factors. On average, teachers in part-time positions reported 36 and in full-time positions 42 h per week. The effort-reward ratios were significantly associated with the volume of employment. Teachers in part-time jobs had only a slightly lower ERI-ratio. There were no differences between full-time and part-time teachers regarding health status. Eighteen percentage of both groups reported impaired mental health (GHQ ≥ 5), 48% of part-time teachers and 53% of full-time teachers suffered from high blood pressure. Low physical fitness was observed in 12% of part-time and 6% of full-time teachers. In this study, neither the volume of employment nor working conditions were found to be significantly correlated with health status. Part-time and full-time employment status did not appear to influence health in the teaching profession. Although there are differences in quantitative working demands, while the health status does not differ between both teacher groups.

The relationship between agreeableness and the development of the working alliance in patients with borderline personality disorder.

PubMed

Hirsh, Jacob B; Quilty, Lena C; Bagby, R Michael; McMain, Shelley F

2012-08-01

The working alliance between therapist and patient is an important component of effective interventions for borderline personality disorder (BPD). The current study examines whether client personality affects the development of the working alliance during the treatment of BPD, and whether this influences treatment effectiveness. Data was based on 87 patients with BPD who were participants in a randomized controlled trial comparing Dialectical Behavior Therapy (DBT) and general psychiatric management. Higher levels of trait Agreeableness were associated with steeper increases in working alliance throughout treatment, but only in the DBT condition. Increases in working alliance were in turn associated with better clinical outcomes. Mediation models revealed a significant indirect path from Agreeableness to better clinical outcomes, mediated through larger improvements in working alliance over time. These results highlight the role that patient personality can play during the therapeutic process, with a specific focus on the importance of Agreeableness for alliance development.

The impact of a microsavings intervention on reducing violence against women engaged in sex work: a randomized controlled study.

PubMed

Tsai, Laura Cordisco; Carlson, Catherine E; Aira, Toivgoo; Norcini Pala, Andrea; Riedel, Marion; Witte, Susan S

2016-10-28

Women who engage in sex work are at risk for experiencing violence from numerous perpetrators, including paying partners. Empirical evidence has shown mixed results regarding the impact of participation in microfinance interventions on women's experiences of violence, with some studies demonstrating reductions in intimate partner violence (IPV) and others showing heightened risk for IPV. The current study reports on the impact of participation in a microsavings intervention on experiences of paying partner violence among women engaged in sex work in Mongolia. Between 2011 and 2013, we conducted a two-arm, non-blinded randomized controlled trial (RCT) comparing an HIV/STI risk reduction intervention (HIVSRR) (control condition) to a combined microsavings and HIVSRR intervention (treatment condition). Eligible women (aged 18 or older, reported having engaged in unprotected sex with paying partner in past 90 days, expressed interest in microsavings intervention) were invited to participate. One hundred seven were randomized, including 50 in the control and 57 in the treatment condition. Participants completed assessments at baseline, immediate post-test following HIVSRR, and at 3-months and 6-months after completion of the treatment group intervention. Outcomes for the current study include any violence (physical and/or sexual), sexual violence, and physical violence from paying partners in the past 90 days. An intention-to-treat approach was utilized. Linear growth models revealed significant reductions over time in both conditions for any violence (β = -0.867, p < 0.001), physical violence (β = -0.0923, p < 0.001), and sexual violence (β = -1.639, p = 0.001) from paying partners. No significant differences between groups were found for any violence (β = 0.118, p = 0.389), physical violence (β = 0.091, p = 0.792), or sexual violence (β = 0.379, p = 0.114) from paying partners. Microsavings participation did not significantly impact women's risk for paying partner violence. Qualitative research is recommended to understand the cause for reductions in paying partner violence in both study conditions. Evaluating a Microfinance Intervention for High Risk Women in Mongolia; NCT01861431 ; May 20, 2013.

Conditional bistability, a generic cellular mnemonic mechanism for robust and flexible working memory computations.

PubMed

Rodriguez, Guillaume; Sarazin, Matthieu; Clemente, Alexandra; Holden, Stephanie; Paz, Jeanne T; Delord, Bruno

2018-04-30

Persistent neural activity, the substrate of working memory, is thought to emerge from synaptic reverberation within recurrent networks. However, reverberation models do not robustly explain fundamental dynamics of persistent activity, including high-spiking irregularity, large intertrial variability, and state transitions. While cellular bistability may contribute to persistent activity, its rigidity appears incompatible with persistent activity labile characteristics. Here, we unravel in a cellular model a form of spike-mediated conditional bistability that is robust, generic and provides a rich repertoire of mnemonic computations. Under asynchronous synaptic inputs of the awakened state, conditional bistability generates spiking/bursting episodes, accounting for the irregularity, variability and state transitions characterizing persistent activity. This mechanism has likely been overlooked because of the sub-threshold input it requires and we predict how to assess it experimentally. Our results suggest a reexamination of the role of intrinsic properties in the collective network dynamics responsible for flexible working memory. SIGNIFICANCE STATEMENT This study unravels a novel form of intrinsic neuronal property, i.e. conditional bistability. We show that, thanks of its conditional character, conditional bistability favors the emergence of flexible and robust forms of persistent activity in PFC neural networks, in opposition to previously studied classical forms of absolute bistability. Specifically, we demonstrate for the first time that conditional bistability 1) is a generic biophysical spike-dependent mechanism of layer V pyramidal neurons in the PFC and that 2) it accounts for essential neurodynamical features for the organisation and flexibility of PFC persistent activity (the large irregularity and intertrial variability of the discharge and its organization under discrete stable states), which remain unexplained in a robust fashion by current models. Copyright © 2018 the authors.

Patterns and expenditures of multi-morbidity in an insured working population in the United States: insights for a sustainable health care system and building healthier lives.

PubMed

Greene, Robert; Dasso, Edwin; Ho, Sam; Frank, Jerry; Scandrett, Graeme; Genaidy, Ash

2013-12-01

The U.S. health care system is currently heading toward unsustainable health care expenditures and increased dissatisfaction with health outcomes. The objective of this population-based study is to uncover practical insights regarding patients with 1 or more chronic illnesses. A cross-sectional investigation was designed to gather data from health records drawn from diverse US geographic markets. A database of 9.74 million fully-insured, working individuals was used, together with members in the same households. Among nearly 3.43 million patients with claims, 2.22 million had chronic conditions. About 24.3% had 1 chronic condition and 40.4% had multi-morbidity. Health care expenditures for chronic conditions accounted for 92% of all costs (52% for chronic costs and 40% for nonchronic costs). Psychiatry, orthopedics-rheumatology, endocrinology, and cardiology areas accounted for two thirds of these chronic condition costs; nonchronic condition costs were dominated by otolaryngology, gastroenterology, dermatology, orthopedics-rheumatology conditions, and preventive services. About 50.1% of all households had 2 or more members with chronic conditions. In summary, multi-morbidity is prevalent not only among those older than age 65 years but also in younger and working individuals, and commonly occurs among several members of a household. The authors suggest that the disease-focused model of medicine should change to a more holistic illness-wellness model, emphasizing not only the physical but also the mental and social elements that can influence individual health. In that way the chronic care model could be broadened in context and content to improve the health of patients and households.

Explicit wave action conservation for water waves on vertically sheared flows

NASA Astrophysics Data System (ADS)

Quinn, Brenda; Toledo, Yaron; Shrira, Victor

2016-04-01

Water waves almost always propagate on currents with a vertical structure such as currents directed towards the beach accompanied by an under-current directed back toward the deep sea or wind-induced currents which change magnitude with depth due to viscosity effects. On larger scales they also change their direction due to the Coriolis force as described by the Ekman spiral. This implies that the existing wave models, which assume vertically-averaged currents, is an approximation which is far from realistic. In recent years, ocean circulation models have significantly improved with the capability to model vertically-sheared current profiles in contrast with the earlier vertically-averaged current profiles. Further advancements have coupled wave action models to circulation models to relate the mutual effects between the two types of motion. Restricting wave models to vertically-averaged non-turbulent current profiles is obviously problematic in these cases and the primary goal of this work is to derive and examine a general wave action equation which accounts for these shortcoming. The formulation of the wave action conservation equation is made explicit by following the work of Voronovich (1976) and using known asymptotic solutions of the boundary value problem which exploit the smallness of the current magnitude compared to the wave phase velocity and/or its vertical shear and curvature. The adopted approximations are shown to be sufficient for most of the conceivable applications. This provides correction terms to the group velocity and wave action definition accounting for the shear effects, which are fitting for application to operational wave models. In the limit of vanishing current shear, the new formulation reduces to the commonly used Bretherton & Garrett (1968) no-shear wave action equation where the invariant is calculated with the current magnitude taken at the free surface. It is shown that in realistic oceanic conditions, the neglect of the vertical structure of the currents in wave modelling which is currently universal, might lead to significant errors in wave amplitude and the predicted wave ray paths. An extension of the work toward the more complex case of turbulent currents will also be discussed.

Probabilistic modeling of condition-based maintenance strategies and quantification of its benefits for airliners

NASA Astrophysics Data System (ADS)

Pattabhiraman, Sriram

Airplane fuselage structures are designed with the concept of damage tolerance, wherein small damage are allowed to remain on the airplane, and damage that otherwise affect the safety of the structure are repaired. The damage critical to the safety of the fuselage are repaired by scheduling maintenance at pre-determined intervals. Scheduling maintenance is an interesting trade-off between damage tolerance and cost. Tolerance of larger damage would require less frequent maintenance and hence, a lower cost, to maintain a certain level of reliability. Alternatively, condition-based maintenance techniques have been developed using on-board sensors, which track damage continuously and request maintenance only when the damage size crosses a particular threshold. This effects a tolerance of larger damage than scheduled maintenance, leading to savings in cost. This work quantifies the savings of condition-based maintenance over scheduled maintenance. The work also quantifies converting the cost savings into weight savings. Structural health monitoring will need time to be able to establish itself as a stand-alone system for maintenance, due to concerns on its diagnosis accuracy and reliability. This work also investigates the effect of synchronizing structural health monitoring system with scheduled maintenance. This work uses on-board SHM equipment skip structural airframe maintenance (a subsect of scheduled maintenance), whenever deemed unnecessary while maintain a desired level of safety of structure. The work will also predict the necessary maintenance for a fleet of airplanes, based on the current damage status of the airplanes. The work also analyses the possibility of false alarm, wherein maintenance is being requested with no critical damage on the airplane. The work use SHM as a tool to identify lemons in a fleet of airplanes. Lemons are those airplanes that would warrant more maintenance trips than the average behavior of the fleet.

Electrical coupled Morris-Lecar neurons: From design to pattern analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Binczak, S.; Behdad, R.; Rossé, M.

2016-06-08

In this study, an experimental electronic neuron based on Morris-Lecar model is presented, able to become an experimental unit tool to study collective association of robust coupled neurons. The circuit design is given according to the ionic currents of this model. A weak coupling of such neurons under Multisim Software can generate clusters based on the boundary conditions of the neurons and their initial conditions. For this study, we work in the region close to the fold bifurcation of limit cycles. In this region two limit cycles exist, one of the cycles is stable and another one is unstable.

Control of arc length during gas metal arc welding

DOE Office of Scientific and Technical Information (OSTI.GOV)

Madigan, R.B.; Quinn, T.P.

1994-12-31

An arc-length control system has been developed for gas metal arc welding (GMAW) under spray transfer welding conditions. The ability to monitor and control arc length during arc welding allows consistent weld characteristics to be maintained and therefore improves weld quality. Arc length control has only been implemented for gas tungsten arc welding (GTAW), where an automatic voltage control (AVC) unit adjusts torch-to-work distance. The system developed here compliments the voltage- and current-sensing techniques commonly used for control of GMAW. The system consists of an arc light intensity sensor (photodiode), a Hall-effect current sensor, a personal computer and software implementingmore » a data interpretation and control algorithms. Arc length was measured using both arc light and arc current signals. Welding current was adjusted to maintain constant arc length. A proportional-integral-derivative (PID) controller was used. Gains were automatically selected based on the desired welding conditions. In performance evaluation welds, arc length varied from 2.5 to 6.5 mm while welding up a sloped workpiece (ramp in CTWD) without the control. Arc length was maintained within 1 mm of the desired (5 mm ) with the control.« less

Optical spectroscopy of laser-produced plasmas for standoff isotopic analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harilal, Sivanandan S.; Brumfield, Brian E.; LaHaye, Nicole L.

2018-04-20

This review article covers the present status of isotope detection through emission, absorption, and fluorescence spectroscopy of atoms and molecules in a laser-produced plasma formed from a solid sample. A description of the physics behind isotope shifts in atoms and molecules is presented, followed by the physics behind solid sampling of laser ablation plumes, optical methods for isotope measurements, the suitable physical conditions of laser-produced plasma plumes for isotopic analysis, and the current status. Finally, concluding remarks will be made on the existing gaps between previous works in the literature and suggestions for future work.

Optical spectroscopy of laser-produced plasmas for standoff isotopic analysis

DOE PAGES

Harilal, S. S.; Brumfield, B. E.; LaHaye, N. L.; ...

2018-04-20

This review article covers the present status of isotope detection through emission, absorption, and fluorescence spectroscopy of atoms and molecules in a laser-produced plasma formed from a solid sample. A description of the physics behind isotope shifts in atoms and molecules is presented, followed by the physics behind solid sampling of laser ablation plumes, optical methods for isotope measurements, the suitable physical conditions of laser-produced plasma plumes for isotopic analysis, and the current status. Lastly, concluding remarks will be made on the existing gaps between previous works in the literature and suggestions for future work.

Optical spectroscopy of laser-produced plasmas for standoff isotopic analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harilal, S. S.; Brumfield, B. E.; LaHaye, N. L.

This review article covers the present status of isotope detection through emission, absorption, and fluorescence spectroscopy of atoms and molecules in a laser-produced plasma formed from a solid sample. A description of the physics behind isotope shifts in atoms and molecules is presented, followed by the physics behind solid sampling of laser ablation plumes, optical methods for isotope measurements, the suitable physical conditions of laser-produced plasma plumes for isotopic analysis, and the current status. Finally, concluding remarks will be made on the existing gaps between previous works in the literature and suggestions for future work.

Optical spectroscopy of laser-produced plasmas for standoff isotopic analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harilal, S. S.; Brumfield, B. E.; LaHaye, N. L.

This review article covers the present status of isotope detection through emission, absorption, and fluorescence spectroscopy of atoms and molecules in a laser-produced plasma formed from a solid sample. A description of the physics behind isotope shifts in atoms and molecules is presented, followed by the physics behind solid sampling of laser ablation plumes, optical methods for isotope measurements, the suitable physical conditions of laser-produced plasma plumes for isotopic analysis, and the current status. Lastly, concluding remarks will be made on the existing gaps between previous works in the literature and suggestions for future work.

Addressing the migration of health professionals: the role of working conditions and educational placements.

PubMed

Witt, Julia

2009-11-18

This article provides a brief overview of the global health-worker shortage, which could undermine the Millennium Development Goal to halt and begin to reverse the spread of HIV/AIDS. The current situation suggests that long-term solutions to shortages can only be found by addressing the problem from a global perspective; that is, to eliminate shortages through substantial investments in training and retaining health workers in developed and developing countries, and not through policies that do not work towards solving this underlying problem, such as ones that restrict migration.

Optical spectroscopy of laser-produced plasmas for standoff isotopic analysis

DOE PAGES

Harilal, S. S.; Brumfield, B. E.; LaHaye, N. L.; ...

2018-06-01

This review article covers the present status of isotope detection through emission, absorption, and fluorescence spectroscopy of atoms and molecules in a laser-produced plasma formed from a solid sample. A description of the physics behind isotope shifts in atoms and molecules is presented, followed by the physics behind solid sampling of laser ablation plumes, optical methods for isotope measurements, the suitable physical conditions of laser-produced plasma plumes for isotopic analysis, and the current status. Finally, concluding remarks will be made on the existing gaps between previous works in the literature and suggestions for future work.

The Effects of Neutral Inertia on Ionospheric Currents in the High-Latitude Thermosphere Following a Geomagnetic Storm

NASA Technical Reports Server (NTRS)

Deng, W.; Killeen, T. L.; Burns, A. G.; Roble, R. G.; Slavin, J. A.; Wharton, L. E.

1993-01-01

Results of an experimental and theoretical investigation into the effects of the time dependent neutral wind flywheel on high-latitude ionospheric electrodynamics are presented. The results extend our previous work which used the National Center for Atmospheric Research Thermosphere/Ionosphere General Circulation Model (NCAR TIGCM) to theoretically simulate flywheel effects in the aftermath of a geomagnetic storm. The previous results indicated that the neutral circulation, set up by ion-neutral momentum coupling in the main phase of a geomagnetic storm, is maintained for several hours after the main phase has ended and may dominate height-integrated Hall currents and field-aligned currents for up to 4-5 hours. We extend the work of Deng et al. to include comparisons between the calculated time-dependent ionospheric Hall current system in the storm-time recovery period and that measured by instruments on board the Dynamics Explorer 2 (DE 2) satellite. Also, comparisons are made between calculated field-aligned currents and those derived from DE 2 magnetometer measurements. These calculations also allow us to calculate the power transfer rate (sometimes called the Poynting flux) between the magnetosphere and ionosphere. The following conclusions have been drawn: (1) Neutral winds can contribute significantly to the horizontal ionospheric current system in the period immediately following the main phase of a geomagnetic storm, especially over the magnetic polar cap and in regions of ion drift shear. (2) Neutral winds drive Hall currents that flow in the opposite direction to those driven by ion drifts. (3) The overall morphology of the calculated field-aligned current system agrees with previously published observations for the interplanetary magnetic field (IMF) B(sub Z) southward conditions, although the region I and region 2 currents are smeared by the TI(ICM model grid resolution. (4) Neutral winds can make significant contributions to the field-aligned current system when B(sub Z) northward conditions prevail following the main phase of a storm, but can account for only a fraction of the observed currents. (5) DE 2 measurements provide a demonstration of "local" (satellite-altitude) flywheel effects. (6) On the assumption that the magnetosphere acts as an insulator, we calculate neutral-wind-induced polarization electric fields of approx. 20-30 kV in the period immediately following the geomagnetic storm.

A Social Practice Approach to Understanding Teachers' Learning to Use Technology and Digital Literacies in the Classroom

ERIC Educational Resources Information Center

Kalman, Judy; Guerrero, Elsa

2013-01-01

Current educational policy in Mexico, as in many other parts of the world, leans heavily on teachers to use computers in their classrooms. This article explores under what conditions teachers are willing to learn about and use digital technology in their work. The authors' central premise is that incorporating technology into teaching is a complex…

Defibrillation of the Heart With Low Tension Currents in Experimental Conditions.

DTIC Science & Technology

1960-05-04

the coronary vessels. It became clear with the accumulation of subsequent ob- servations that chemical preparations in themselves are not im...the recommended chemopharmaceutical means against difibrillation were directed towards a decrease of the excitability Of the hearti numerous...Intracardiac Conductivity. "Klin. Med." (Clinical Medicine), No 3, 1956. Litman, N., Surgical Treatment of Heart Diseases . Works of the 26th Congress of

The Effects of Childhood ADHD on Adult Labor Market Outcomes. NBER Working Paper No. 18689

ERIC Educational Resources Information Center

Fletcher, Jason

2013-01-01

While several types of mental illness, including substance abuse disorders, have been linked with poor labor market outcomes, no current research has been able to examine the effects of childhood ADHD. As ADHD has become one of the most prevalent childhood mental conditions, it is useful to understand the full set of consequences of the illness.…

Profile of Home Care Aides, Nursing Home Aides, and Hospital Aides: Historical Changes and Data Recommendations

ERIC Educational Resources Information Center

Yamada, Yoshiko

2002-01-01

Purpose: To examine demographic characteristics and work conditions of home care aides, nursing home aides, and hospital aides in the late 1980s and late 1990s. Design and Methods: This study replicated a previous study which examined the Current Population Survey (CPS) March supplement from 1987 to 1989. The present study examined CPS data from…

International Work Group for Indigenous Affairs Newsletter, July 1991-December 1992 = Boletin de Grupo Internacional de Trabajo sobre Asuntos Indigenas, Septiembre 1991-Diciembre 1992.

ERIC Educational Resources Information Center

IWGIA Newsletter, 1992

1992-01-01

This document contains seven consecutive English-language issues of the IWGIA Newsletter, from July 1991 through December 1992, followed by the seven corresponding issues in Spanish. These newsletters provide educators with a resource on the history, current conditions, and struggles for self-determination of indigenous peoples around the world.…

From the Telescope to the Laboratory and Back Again: The Center for Astrophysical Plasma Properties

NASA Astrophysics Data System (ADS)

Houston Montgomery, Michael; Winget, Don; Schaeuble, Marc; Hawkins, Keith; Wheeler, Craig

2018-01-01

The Center for Astrophysical Plasma Properties (CAPP) is a new center focusing on the spectroscopic properties of stars and accretion disks using “at-parameter” experiments. Currently, these experiments use the X-ray output of the Z machine at Sandia National Laboratories—the largest X-ray source in the world—to heat plasmas to the same conditions (temperature, density, and radiation environment) as those observed in astronomical objects. Current experiments include measuring (1) density-dependent opacities of iron-peak elements at solar interior conditions, (2) spectral lines of low-Z elements at white dwarf photospheric conditions, (3) atomic population kinetics of neon in a radiation-dominated environment, and (4) resonant Auger destruction (RAD) of silicon at accretion disk conditions around supermassive black holes. We will be moving to new astrophysical environments and additional experimental facilities, such as the National Ignition Facility (NIF) and the OMEGA facility at the Laboratory for Laser Energetics (LLE). We seek students and collaborators to work on these experiments as well as the calculations that complement them. CAPP has funding for 5 years and can support up to six graduate students and three post-docs.

Why S, Not X, Marks the Spot for CME/Flare Eruptions

NASA Technical Reports Server (NTRS)

Moore, Ronald L.; Sterling, Alphonse; Gary, Allen; Cirtain, Jonathan; Falconer, David

2010-01-01

For any major CME/flare eruption: I. The field that erupts is an arcade in which the interior is greatly sheared and twisted. Most of the free magnetic energy to be released: a) Is in the shear and twist of the interior field. b) Is Not due to a big current sheet. The eruption is unleashed by reconnection at a growing current sheet. The current sheet is still little when the reconnection turns on. The unleashed eruption then makes the current sheet much bigger by building it up faster than the reconnection can tear it down. II. Most X-ray jets work the opposite way: a) Tapped free energy is in the field of a pre-jet current sheet. b) Current sheet built by small arcade emerging into ambient field. c) Current sheet still much smaller than the arcade when reconnection turns on and tears it down, producing a jet. III. These rules reflect the low-beta condition in the eruptive magnetic field

The authentic worker's well-being and performance: the relationship between authenticity at work, well-being, and work outcomes.

PubMed

van den Bosch, Ralph; Taris, Toon W

2014-01-01

Previous research on authenticity has mainly focused on trait conceptualizations of authenticity (e.g., Wood et al., 2008), whereas in specific environments (e.g., at work) state conceptualizations of authenticity (cf. Van den Bosch & Taris, 2013) are at least as relevant. For example, working conditions are subject to change, and this could well have consequences for employees' perceived level of authenticity at work. The current study employs a work-specific, state-like conceptualization of authenticity to investigate the relations between authenticity at work, well-being, and work outcomes. A series of ten separate hierarchical regression analyses using data from 685 participants indicated that after controlling for selected work characteristics and demographic variables, authenticity at work accounted for on average 11% of the variance of various wellbeing and work outcomes. Of the three subscales of authenticity at work (i.e., authentic living, self-alienation, and accepting influence), self-alienation was the strongest predictor of outcomes, followed by authentic living and accepting external influence, respectively. These findings are discussed in the light of their practical and theoretical implications.

Ink dating using thermal desorption and gas chromatography/mass spectrometry: comparison of results obtained in two laboratories.

PubMed

Koenig, Agnès; Bügler, Jürgen; Kirsch, Dieter; Köhler, Fritz; Weyermann, Céline

2015-01-01

An ink dating method based on solvent analysis was recently developed using thermal desorption followed by gas chromatography/mass spectrometry (GC/MS) and is currently implemented in several forensic laboratories. The main aims of this work were to implement this method in a new laboratory to evaluate whether results were comparable at three levels: (i) validation criteria, (ii) aging curves, and (iii) results interpretation. While the results were indeed comparable in terms of validation, the method proved to be very sensitive to maintenances. Moreover, the aging curves were influenced by ink composition, as well as storage conditions (particularly when the samples were not stored in "normal" room conditions). Finally, as current interpretation models showed limitations, an alternative model based on slope calculation was proposed. However, in the future, a probabilistic approach may represent a better solution to deal with ink sample inhomogeneity. © 2014 American Academy of Forensic Science.

Novel Signal-Amplified Fenitrothion Electrochemical Assay, Based on Glassy Carbon Electrode Modified with Dispersed Graphene Oxide

NASA Astrophysics Data System (ADS)

Wang, Limin; Dong, Jinbo; Wang, Yulong; Cheng, Qi; Yang, Mingming; Cai, Jia; Liu, Fengquan

2016-03-01

A novel signal-amplified electrochemical assay for the determination of fenitrothion was developed, based on the redox behaviour of organophosphorus pesticides on a glassy carbon working electrode. The electrode was modified using graphene oxide dispersion. The electrochemical response of fenitrothion at the modified electrode was investigated using cyclic voltammetry, current-time curves, and square-wave voltammetry. Experimental parameters, namely the accumulation conditions, pH value, and volume of dispersed material, were optimised. Under the optimum conditions, a good linear relationship was obtained between the oxidation peak current and the fenitrothion concentration. The linear range was 1-400 ng·mL-1, with a detection limit of 0.1 ng·mL-1 (signal-to-nose ratio = 3). The high sensitivity of the sensor was demonstrated by determining fenitrothion in pakchoi samples.

Ergonomics Risk Assessment among support staff in Universiti Malaysia Pahang

NASA Astrophysics Data System (ADS)

Jusoh, Faisal; Nafis Osman Zahid, Muhammed

2018-03-01

Awareness of ergonomic risk assessment among workers are getting intense in many industries nowadays. It is essential since most of the workers spend 7 to 8 hours of their time in the workplaces. Previous study shown that spending too much time with static posture in sitting at workplace leads to the problem of Musculoskeletal Disorders (MSDs). The implications are not only harmful to human body but also effect the productivity. Currently, there are no scientific study conducted to assess the conditions of workers in Universiti Malaysia Pahang (UMP). Therefore, the problem of MSDs could not be justified clearly and the top management did not acknowledge this issue. This study aims to present current scenario of ergonomic risk level at UMP by using structured model. It focuses on operational staff from faculties and Human Resources Department (HRD). Initially, three types of assessments are executed based on general working condition, Cornell Muscokeletal Discomfort Questionnaire (CMDQ) and Rapid Office Strain Assessment (ROSA). Based on the findings, 90% of the respondents felt discomfort at workplace but prefer to rectify the issues by themselves. Almost 50% of them evaluated themselves in level 4-5 of discomfort level. The CMDQ result shown the discomfort area at faculties and HRD. The workplace at faculties and HRD had been assessed through ROSA and the overall result shown the risk level is medium level respectively. Therefore, further investigation is requires and improvement of workplace need to be proposed to establish good working condition.

Bioaerosols, Noise, and Ultraviolet Radiation Exposures for Municipal Solid Waste Handlers

PubMed Central

Ncube, Esper Jacobeth; Voyi, Kuku

2017-01-01

Few studies have investigated the occupational hazards of municipal solid waste workers, particularly in developing countries. Resultantly these workers are currently exposed to unknown and unabated occupational hazards that may endanger their health. We determined municipal solid waste workers' work related hazards and associated adverse health endpoints. A multifaceted approach was utilised comprising bioaerosols sampling, occupational noise, thermal conditions measurement, and field based waste compositional analysis. Results from our current study showed highest exposure concentrations for Gram-negative bacteria (6.8 × 103 cfu/m3) and fungi (12.8 × 103 cfu/m3), in the truck cabins. Significant proportions of toxic, infectious, and surgical waste were observed. Conclusively, municipal solid waste workers are exposed to diverse work related risks requiring urgent sound interventions. A framework for assessing occupational risks of these workers must prioritize performance of exposure assessment with regard to the physical, biological, and chemical hazards of the job. PMID:28167969

Bioaerosols, Noise, and Ultraviolet Radiation Exposures for Municipal Solid Waste Handlers.

PubMed

Ncube, France; Ncube, Esper Jacobeth; Voyi, Kuku

2017-01-01

Few studies have investigated the occupational hazards of municipal solid waste workers, particularly in developing countries. Resultantly these workers are currently exposed to unknown and unabated occupational hazards that may endanger their health. We determined municipal solid waste workers' work related hazards and associated adverse health endpoints. A multifaceted approach was utilised comprising bioaerosols sampling, occupational noise, thermal conditions measurement, and field based waste compositional analysis. Results from our current study showed highest exposure concentrations for Gram-negative bacteria (6.8 × 10 3  cfu/m 3 ) and fungi (12.8 × 10 3  cfu/m 3 ), in the truck cabins. Significant proportions of toxic, infectious, and surgical waste were observed. Conclusively, municipal solid waste workers are exposed to diverse work related risks requiring urgent sound interventions. A framework for assessing occupational risks of these workers must prioritize performance of exposure assessment with regard to the physical, biological, and chemical hazards of the job.

2,3 Butanediol production in an obligate photoautotrophic cyanobacterium in dark conditions via diverse sugar consumption.

PubMed

McEwen, Jordan T; Kanno, Masahiro; Atsumi, Shota

2016-07-01

Cyanobacteria are under investigation as a means to utilize light energy to directly recycle CO2 into chemical compounds currently derived from petroleum. Any large-scale photosynthetic production scheme must rely on natural sunlight for energy, thereby limiting production time to only lighted hours during the day. Here, an obligate photoautotrophic cyanobacterium was engineered for enhanced production of 2,3-butanediol (23BD) in continuous light, 12h:12h light-dark diurnal, and continuous dark conditions via supplementation with glucose or xylose. This study achieved 23BD production under diurnal conditions comparable to production under continuous light conditions. The maximum 23BD titer was 3.0gL(-1) in 10d. Also achieving chemical production under dark conditions, this work enhances the feasibility of using cyanobacteria as industrial chemical-producing microbes. Copyright © 2016 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

Generation of synthetic surface electromyography signals under fatigue conditions for varying force inputs using feedback control algorithm.

PubMed

Venugopal, G; Deepak, P; Ghosh, Diptasree M; Ramakrishnan, S

2017-11-01

Surface electromyography is a non-invasive technique used for recording the electrical activity of neuromuscular systems. These signals are random, complex and multi-component. There are several techniques to extract information about the force exerted by muscles during any activity. This work attempts to generate surface electromyography signals for various magnitudes of force under isometric non-fatigue and fatigue conditions using a feedback model. The model is based on existing current distribution, volume conductor relations, the feedback control algorithm for rate coding and generation of firing pattern. The result shows that synthetic surface electromyography signals are highly complex in both non-fatigue and fatigue conditions. Furthermore, surface electromyography signals have higher amplitude and lower frequency under fatigue condition. This model can be used to study the influence of various signal parameters under fatigue and non-fatigue conditions.

Low-energy ion irradiation in HiPIMS to enable anatase TiO2 selective growth

NASA Astrophysics Data System (ADS)

Cemin, Felipe; Tsukamoto, Makoto; Keraudy, Julien; Antunes, Vinícius Gabriel; Helmersson, Ulf; Alvarez, Fernando; Minea, Tiberiu; Lundin, Daniel

2018-06-01

High power impulse magnetron sputtering (HiPIMS) has already demonstrated great potential for synthesizing the high-energy crystalline phase of titanium dioxide (rutile TiO2) due to large quantities of highly energetic ions present in the discharge. In this work, it is shown that the metastable anatase phase can also be obtained by HiPIMS. The required deposition conditions have been identified by systematically studying the phase formation, microstructure and chemical composition as a function of mode of target operation as well as of substrate temperature, working pressure, and peak current density. It is found that films deposited in the metal and transition modes are predominantly amorphous and contain substoichiometric TiO x compounds, while in compound mode they are well-crystallized and present only O2‑ ions bound to Ti4+, i.e. pure TiO2. Anatase TiO2 films are obtained for working pressures between 1 and 2 Pa, a peak current density of ~1 A cm‑2 and deposition temperatures lower than 300 °C. Rutile is favored at lower pressures (<1 Pa) and higher peak current densities (>2 A cm‑2), while amorphous films are obtained at higher pressures (5 Pa). Microstructural characterization of selected films is also presented.

Polypyrrol/chitosan hydrogel hybrid microfiber as sensing artificial muscle

NASA Astrophysics Data System (ADS)

Ismail, Yahya A.; Martínez, Jose G.; Al Harrasi, Ahmad S.; Kim, Seon J.; Fernández Otero, Toribio F.

2011-04-01

An electrochemical actuator demands that it should act as a sensor of the working conditions for its efficient application in devices. Actuation and sensing characteristics of a biopolymer/conducting polymer hybrid microfiber artificial muscle fabricated through wet spinning of a chitosan solution followed by in situ chemical polymerization with pyrrol employing bis(triflouro methane sulfonyl) imide as dopant and ferric chloride as a catalyst is presented. The polypyrrol/chitosan hybrid microfiber was investigated by FTIR, scanning electron microscopy (SEM), electrical conductivity measurement, cyclic voltammetric and chronopotentiometric methods. The electrochemical measurements related to the sensing abilities were performed as a function of applied current, concentration and temperature keeping two of the variables constant at a given time using NaCl as electrolyte. Cyclic voltammograms confirmed that the electro activity is imparted by polypyrrol (pPy). The fiber showed an electrical conductivity of 3.21x10-1 Scm-1and an average linear electrochemical actuation strain of 0.54%. The chronopotentiometric responses during the oxidation/reduction processes of the microfiber for the different anodic/cathodic currents and the linear fit observed for the consumed electrical energy during the reaction for various applied currents suggested that it can act as a sensor of applied current. The chronopotentiometric responses and the linear fit of consumed electrical energy at different temperatures suggested that the actuator can act as a temperature sensor. Similarly a semi logarithmic dependence of the consumed electrical energy with concentration of the electrolyte during reaction is suggestive of its applicability as a concentration sensor. The demand that an electrochemical actuator to be a sensor of the working conditions, for its efficient application in devices is thus verified in this material.

The ergonomic process of an automotive company in Brazil: a study case.

PubMed

Bustos, Carolina; Fischer, Daniela; Ballardin, Lucimara; Nielsen, Rudolf

2012-01-01

The goal of this paper is to present the ergonomic process of an automotive company, whose focus is on the adaptation of the work conditions to the psychophysiological characteristics of its employees. The planning and the development of the ergonomic actions took place in three distinctive stages: ergonomic analysis of the work post (stage 1), ergonomic adaptations (stage 2) and Ergonomic Committee (stage 3). The activities started in June 2006 and have lasted to the current date, keeping a permanent improving process. The procedure adopted was based on the ergonomic analysis methodology proposed by Wisner (1994:1997) and the stages of the Ergonomic Analysis of Work presented in the 17 NR Regulatory Manual (MET, 2002). The paper's approach focused on the voluntary participation of workers from different areas and different hierarchical levels of the organization throughout all the stages of the process. The methodological procedures included descriptive research techniques, exploratory and qualitative research criteria, background and guidelines available in literature and legislation, as well as company information. Among the main results it can be mentioned the satisfaction of the employees regarding the appropriate work conditions, cultural and organizational changes and the creation of an Ergonomic Committee in the company.

Working memory training in healthy young adults: Support for the null from a randomized comparison to active and passive control groups.

PubMed

Clark, Cameron M; Lawlor-Savage, Linette; Goghari, Vina M

2017-01-01

Training of working memory as a method of increasing working memory capacity and fluid intelligence has received much attention in recent years. This burgeoning field remains highly controversial with empirically-backed disagreements at all levels of evidence, including individual studies, systematic reviews, and even meta-analyses. The current study investigated the effect of a randomized six week online working memory intervention on untrained cognitive abilities in a community-recruited sample of healthy young adults, in relation to both a processing speed training active control condition, as well as a no-contact control condition. Results of traditional null hypothesis significance testing, as well as Bayesian factor analyses, revealed support for the null hypothesis across all cognitive tests administered before and after training. Importantly, all three groups were similar at pre-training for a variety of individual variables purported to moderate transfer of training to fluid intelligence, including personality traits, motivation to train, and expectations of cognitive improvement from training. Because these results are consistent with experimental trials of equal or greater methodological rigor, we suggest that future research re-focus on: 1) other promising interventions known to increase memory performance in healthy young adults, and; 2) examining sub-populations or alternative populations in which working memory training may be efficacious.

Expanded solutions of force-free electrodynamics on general Kerr black holes

NASA Astrophysics Data System (ADS)

Li, Huiquan; Wang, Jiancheng

2017-07-01

In this work, expanded solutions of force-free magnetospheres on general Kerr black holes are derived through a radial distance expansion method. From the regular conditions both at the horizon and at spatial infinity, two previously known asymptotical solutions (one of them is actually an exact solution) are identified as the only solutions that satisfy the same conditions at the two boundaries. Taking them as initial conditions at the boundaries, expanded solutions up to the first few orders are derived by solving the stream equation order by order. It is shown that our extension of the exact solution can (partially) cure the problems of the solution: it leads to magnetic domination and a mostly timelike current for restricted parameters.

Undocumented Migrants in Canada: A scope literature review on health, access to services, and working conditions

PubMed Central

Carrasco, Christine; Gastaldo, Denise

2011-01-01

It is estimated that there are 30 to 40 million undocumented workers worldwide. Although undocumented migration has become an issue of high international relevance, it has been strikingly understudied in Canada, especially with respect to its impact on health. The purpose of this study is to explore the concept of undocumentedness in Canada through a scoping review of peer-reviewed and grey literature written in English, French, Portuguese and Spanish between 2002 and 2008. The specific aims are to: i) summarize and disseminate current academic and community-based findings on the health, service access and working conditions of undocumented migrants in Canada; ii) examine the sources and use of evidence; iii) identify significant gaps in existing knowledge; iv) set recommendations for policy and research, including considerations on transnationalism, ethics, interdisciplinary approaches, gender differences, resilience, and impact on the children of non-status parents. PMID:19657739

Effects of Distributed Generation on Overcurrent Relay Coordination and an Adaptive Protection Scheme

NASA Astrophysics Data System (ADS)

Ilik, Semih C.; Arsoy, Aysen B.

2017-07-01

Integration of distributed generation (DG) such as renewable energy sources to electrical network becomes more prevalent in recent years. Grid connection of DG has effects on load flow directions, voltage profile, short circuit power and especially protection selectivity. Applying traditional overcurrent protection scheme is inconvenient when system reliability and sustainability are considered. If a fault happens in DG connected network, short circuit contribution of DG, creates additional branch element feeding the fault current; compels to consider directional overcurrent (OC) protection scheme. Protection coordination might get lost for changing working conditions when DG sources are connected. Directional overcurrent relay parameters are determined for downstream and upstream relays when different combinations of DG connected singular or plural, on radial test system. With the help of proposed flow chart, relay parameters are updated and coordination between relays kept sustained for different working conditions in DigSILENT PowerFactory program.

Scaled Rocket Testing in Hypersonic Flow

NASA Technical Reports Server (NTRS)

Dufrene, Aaron; MacLean, Matthew; Carr, Zakary; Parker, Ron; Holden, Michael; Mehta, Manish

2015-01-01

NASA's Space Launch System (SLS) uses four clustered liquid rocket engines along with two solid rocket boosters. The interaction between all six rocket exhaust plumes will produce a complex and severe thermal environment in the base of the vehicle. This work focuses on a recent 2% scale, hot-fire SLS base heating test. These base heating tests are short-duration tests executed with chamber pressures near the full-scale values with gaseous hydrogen/oxygen engines and RSRMV analogous solid propellant motors. The LENS II shock tunnel/Ludwieg tube tunnel was used at or near flight duplicated conditions up to Mach 5. Model development was strongly based on the Space Shuttle base heating tests with several improvements including doubling of the maximum chamber pressures and duplication of freestream conditions. Detailed base heating results are outside of the scope of the current work, rather test methodology and techniques are presented along with broader applicability toward scaled rocket testing in supersonic and hypersonic flow.

Adaptive Working Memory Training Reduces the Negative Impact of Anxiety on Competitive Motor Performance.

PubMed

Ducrocq, Emmanuel; Wilson, Mark; Smith, Tim J; Derakshan, Nazanin

2017-12-01

Optimum levels of attentional control are essential to prevent athletes from experiencing performance breakdowns under pressure. The current study explored whether training attentional control using the adaptive dual n-back paradigm, designed to directly target processing efficiency of the main executive functions of working memory (WM), would result in transferrable effects on sports performance outcomes. A total of 30 tennis players were allocated to an adaptive WM training or active control group and underwent 10 days of training. Measures of WM capacity as well as performance and objective gaze indices of attentional control in a tennis volley task were assessed in low- and high-pressure posttraining conditions. Results revealed significant benefits of training on WM capacity, quiet eye offset, and tennis performance in the high-pressure condition. Our results confirm and extend previous findings supporting the transfer of cognitive training benefits to objective measures of sports performance under pressure.

Empirically Supported Treatment’s Impact on Organizational Culture and Climate

PubMed Central

Patterson-Silver Wolf, David A.; Dulmus, Catherine N.; Maguin, Eugene

2012-01-01

Objectives With the continued push to implement empirically supported treatments (ESTs) into community-based organizations, it is important to investigate whether working condition disruptions occur during this process. While there are many studies investigating best practices and how to adopt them, the literature lacks studies investigating the working conditions in programs that currently use ESTs. Method This study compared the culture and climate scores of a large organization’s programs that use ESTs and those programs indicating no EST usage. Results Of the total 55 different programs (1,273 frontline workers), 27 programs used ESTs. Results indicate that the programs offering an EST had significantly more rigid and resistant cultures, compared to those without any ESTs. In regard to climate, programs offering an EST were significantly less engaged, less functional, and more stressed. Conclusion Outcomes indicate a significant disruption in organizational culture and climate for programs offering ESTs. PMID:23243379

Empirically Supported Treatment's Impact on Organizational Culture and Climate.

PubMed

Patterson-Silver Wolf, David A; Dulmus, Catherine N; Maguin, Eugene

2012-11-01

OBJECTIVES: With the continued push to implement empirically supported treatments (ESTs) into community-based organizations, it is important to investigate whether working condition disruptions occur during this process. While there are many studies investigating best practices and how to adopt them, the literature lacks studies investigating the working conditions in programs that currently use ESTs. METHOD: This study compared the culture and climate scores of a large organization's programs that use ESTs and those programs indicating no EST usage. RESULTS: Of the total 55 different programs (1,273 frontline workers), 27 programs used ESTs. Results indicate that the programs offering an EST had significantly more rigid and resistant cultures, compared to those without any ESTs. In regard to climate, programs offering an EST were significantly less engaged, less functional, and more stressed. CONCLUSION: Outcomes indicate a significant disruption in organizational culture and climate for programs offering ESTs.

Investigative study of holographic recording materials development

NASA Technical Reports Server (NTRS)

1972-01-01

The potential of certain cis-trans isomers and doped LiNbO3 for the holographic read/write/erase memory application was investigated. The cis-trans work involved the photochemical investigation of a number of potential materials as well as specific molecular engineering efforts on alpha-methyl stilbene and its derivatives. These efforts resulted in an increase in the change in index of refraction, and thereby, in potential recording utility, of an order of magnitude. The work on LiNbO3 was directed toward a preliminary investigation of the dynamics of the writing process. Several samples and a variety of writing conditions were investigated. An unexpected and as yet unexplained improvement in material behavior with continued recycling was observed. In addition, some effort was devoted to an analysis of the physical conditions under which several current theories of the optical damage process are valid.

Environmentally Friendly Economical Sequestration of Rare Earth Metals from Geothermal Waters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stull, Dean P.

The purpose of this work was to complete a proof of concept study to apply and validate a novel method developed by Tusaar for the capture and recovery of rare earth elements (known as REEs) and other critical and valuable elements from geothermal waters produced from deep within the earth. Geothermal water provides heat for power production at many geothermal power plants in the western United States. The target elements, the REEs, are vital to modern day electronics, batteries, motors, automobiles and many other consumer favorites and necessities. Currently there are no domestic sources of REEs while domestic and internationalmore » demand for the products they are used in continues to rise. Many of the REEs are considered “strategically” important. A secure supply of REEs in the USA would benefit consumers and the country at large. A new method to recover these REEs from geothermal waters used at existing geothermal power plants around the country is a high priority and would benefit consumers and the USA. The result of this project was the successful development and demonstration of an integrated process for removal and recovery of the REEs from synthetic geothermal brines on a small laboratory scale. The work included preparation of model geothermal brines to test, selection of the most effective proprietary sorbent media to capture the REEs and testing of the media under a variety of potential operating conditions. Geothermal brines are generally very high in salt content and contain a wide range of elements and anions associated with the rock layers from which they are produced. Processing the geothermal water is difficult because it is corrosive and the dissolved minerals in the water precipitate easily once the temperature and pressure change. No commercial technologies have been shown to be effective or robust enough under these geothermal brine conditions to be commercially viable for removal of REEs. Technologies including ion exchange, traditional sorptive media and membrane concentration are too expensive, difficult or impossible to regenerate and easily rendered ineffective under these working conditions. The work completed during this project has demonstrated that a selective media that is robust and durable under the conditions associated with geothermal brines is possible. The initial economic analysis indicates that the process would not be financially viable at current market prices for REEs. The world market price for REEs has been turbulent over the past several years and are currently near historical lows. Historical trends and market forces suggest that the world price is stabilizing and will rise. At the same time, further development has the potential to reduce the costs associated with the technology. This work opened the door to the idea that a large scale process for removal and recovery of REEs from geothermal brines is possible. Upward price pressures coupled with technology improvements suggest that this process has the opportunity to be commercially successful at a point in the future.« less

Work related musculoskeletal disorders amongst therapists in physically demanding roles: qualitative analysis of risk factors and strategies for prevention.

PubMed

Passier, Leanne; McPhail, Steven

2011-01-25

Physiotherapy and occupational therapy are two professions at high risk of work related musculoskeletal disorders (WRMD). This investigation aimed to identify risk factors for WRMD as perceived by the health professionals working in these roles (Aim 1), as well as current and future strategies they perceive will allow them to continue to work in physically demanding clinical roles (Aim 2). A two phase exploratory investigation was undertaken. The first phase included a survey administered via a web based platform with qualitative open response items. The second phase involved four focus group sessions which explored topics obtained from the survey. Thematic analysis of qualitative data from the survey and focus groups was undertaken. Overall 112 (34.3%) of invited health professionals completed the survey; 66 (58.9%) were physiotherapists and 46 (41.1%) were occupational therapists. Twenty-four health professionals participated in one of four focus groups. The risk factors most frequently perceived by health professionals included: work postures and movements, lifting or carrying, patient related factors and repetitive tasks. The six primary themes for strategies to allow therapists to continue to work in physically demanding clinical roles included: organisational strategies, workload or work allocation, work practices, work environment and equipment, physical condition and capacity, and education and training. Risk factors as well as current and potential strategies for reducing WRMD amongst these health professionals working in clinically demanding roles have been identified and discussed. Further investigation regarding the relative effectiveness of these strategies is warranted.

A Description of the Development, Capabilities, and Operational Status of the Test SLATE Data Acquisition System at the National Transonic Facility

NASA Technical Reports Server (NTRS)

Cramer, Christopher J.; Wright, James D.; Simmons, Scott A.; Bobbitt, Lynn E.; DeMoss, Joshua A.

2015-01-01

The paper will present a brief background of the previous data acquisition system at the National Transonic Facility (NTF) and the reasoning and goals behind the upgrade to the current Test SLATE (Test Software Laboratory and Automated Testing Environments) data acquisition system. The components, performance characteristics, and layout of the Test SLATE system within the NTF control room will be discussed. The development, testing, and integration of Test SLATE within NTF operations will be detailed. The operational capabilities of the system will be outlined including: test setup, instrumentation calibration, automatic test sequencer setup, data recording, communication between data and facility control systems, real time display monitoring, and data reduction. The current operational status of the Test SLATE system and its performance during recent NTF testing will be highlighted including high-speed, frame-by-frame data acquisition with conditional sampling post-processing applied. The paper concludes with current development work on the system including the capability for real-time conditional sampling during data acquisition and further efficiency enhancements to the wind tunnel testing process.

Method of operator safety assessment for underground mobile mining equipment

NASA Astrophysics Data System (ADS)

Działak, Paulina; Karliński, Jacek; Rusiński, Eugeniusz

2018-01-01

The paper presents a method of assessing the safety of operators of mobile mining equipment (MME), which is adapted to current and future geological and mining conditions. The authors focused on underground mines, with special consideration of copper mines (KGHM). As extraction reaches into deeper layers of the deposit it can activate natural hazards, which, thus far, have been considered unusual and whose range and intensity are different depending on the field of operation. One of the main hazards that affect work safety and can become the main barrier in the exploitation of deposits at greater depths is climate threat. The authors have analysed the phenomena which may impact the safety of MME operators, with consideration of accidents that have not yet been studied and are not covered by the current safety standards for this group of miners. An attempt was made to develop a method for assessing the safety of MME operators, which takes into account the mentioned natural hazards and which is adapted to current and future environmental conditions in underground mines.

The associations of household wealth and income with self-rated health--a study on economic advantage in middle-aged Finnish men and women.

PubMed

Aittomäki, Akseli; Martikainen, Pekka; Laaksonen, Mikko; Lahelma, Eero; Rahkonen, Ossi

2010-09-01

The economic resources available to an individual or a household have been hypothesised to affect health through the direct material effects of living conditions as well as through social comparison and experiences of deprivation. The focus so far has been mainly on current individual or household income, and there is a lack of studies on wealth, a potentially relevant part of household resources. We studied the associations of household wealth and household income with self-rated health, and addressed some theoretical issues related to economic advantage and health. The data were from questionnaire survey of Finnish men and women aged from 45 to 67 years, who were employed by the City of Helsinki from five to seven years before the collection of the data in 2007. We found household wealth to have a strong and consistent association with self-rated health, poor health decreasing with increasing wealth. The relationship was only partly attributable to the association of wealth with employment status, household income, work conditions and health-related behaviour. In contrast, the association of household income with self-rated health was greatly attenuated by taking into account employment status and wealth, and even further attenuated by work conditions. The results suggested a significant contribution of wealth differentials to differences in health status. The insufficiency of current income as the only measure of material welfare was demonstrated. Conditions associated with long-term accumulation of material welfare may be a significant aspect of the causal processes that lead to socioeconomic inequalities in ill health. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

A flexible nursing workforce: realities and fallouts.

PubMed

Grinspun, Doris

2002-01-01

While policy-makers are increasingly concerned about a looming nursing shortage, almost half of Canada's nursing workforce is currently employed on a part-time or casual basis. Why are so many nurses not working full-time and providing the nursing care that would help to alleviate such shortages in our healthcare organizations? Do nurses want to work part-time, or are they driven into this by labour market forces, life demands, poor working conditions and policy decisions external to them? The answers to these questions are critical to ensure that care will be there for all of us. This article presents a brief analysis of flexible employment arrangements in nursing, particularly part-time and casual work, and the impact on nurses, patients and the healthcare system as a whole. Given the sharp increases in these work arrangements in Canada during the last decade, the limited discussion of these trends in the literature is both surprising and troublesome.

Influence of different estrogens on neuroplasticity and cognition in the hippocampus.

PubMed

Barha, Cindy K; Galea, Liisa A M

2010-10-01

Estrogens modulate the morphology and function of the hippocampus. Recent studies have focused on the effects of different types of estrogens on neuroplasticity in the hippocampus and cognition. There are three main forms of estrogens found in mammals: estradiol, estrone, and estriol. The vast majority of studies have used estradiol to investigate the effects of estrogens on the brain. This review focuses on the effects of different estrogens on adult hippocampal neurogenesis, synaptic plasticity in the hippocampus, and cognition in female rats. Different forms of estrogens modulate neuroplasticity and cognition in complex and intriguing ways. Specifically, estrogens upregulate adult hippocampal neurogenesis (via cell proliferation) and synaptic protein levels in the hippocampus in a time- and dose-dependent manner. Low levels of estradiol facilitate spatial working memory and contextual fear conditioning while high levels of estradiol impair spatial working, spatial reference memory and contextual fear conditioning. In addition, estrone impairs contextual fear conditioning. Advances in our knowledge of how estrogens exert their effects on the brain may ultimately lead to refinements in targeted therapies for cognitive impairments at all stages of life. However caution should be taken in interpreting current research and in conducting future studies as estrogens likely work differently in males than in females. Copyright © 2010 Elsevier B.V. All rights reserved.

Intellectual developmental disorders: towards a new name, definition and framework for "mental retardation/intellectual disability" in ICD-11.

PubMed

Salvador-Carulla, Luis; Reed, Geoffrey M; Vaez-Azizi, Leila M; Cooper, Sally-Ann; Martinez-Leal, Rafael; Bertelli, Marco; Adnams, Colleen; Cooray, Sherva; Deb, Shoumitro; Akoury-Dirani, Leyla; Girimaji, Satish Chandra; Katz, Gregorio; Kwok, Henry; Luckasson, Ruth; Simeonsson, Rune; Walsh, Carolyn; Munir, Kemir; Saxena, Shekhar

2011-10-01

Although "intellectual disability" has widely replaced the term "mental retardation", the debate as to whether this entity should be conceptualized as a health condition or as a disability has intensified as the revision of the World Health Organization (WHO)'s International Classification of Diseases (ICD) advances. Defining intellectual disability as a health condition is central to retaining it in ICD, with significant implications for health policy and access to health services. This paper presents the consensus reached to date by the WHO ICD Working Group on the Classification of Intellectual Disabilities. Literature reviews were conducted and a mixed qualitative approach was followed in a series of meetings to produce consensus-based recommendations combining prior expert knowledge and available evidence. The Working Group proposes replacing mental retardation with intellectual developmental disorders, defined as "a group of developmental conditions characterized by significant impairment of cognitive functions, which are associated with limitations of learning, adaptive behaviour and skills". The Working Group further advises that intellectual developmental disorders be incorporated in the larger grouping (parent category) of neurodevelopmental disorders, that current subcategories based on clinical severity (i.e., mild, moderate, severe, profound) be continued, and that problem behaviours be removed from the core classification structure of intellectual developmental disorders and instead described as associated features.

On-board fault management for autonomous spacecraft

NASA Technical Reports Server (NTRS)

Fesq, Lorraine M.; Stephan, Amy; Doyle, Susan C.; Martin, Eric; Sellers, Suzanne

1991-01-01

The dynamic nature of the Cargo Transfer Vehicle's (CTV) mission and the high level of autonomy required mandate a complete fault management system capable of operating under uncertain conditions. Such a fault management system must take into account the current mission phase and the environment (including the target vehicle), as well as the CTV's state of health. This level of capability is beyond the scope of current on-board fault management systems. This presentation will discuss work in progress at TRW to apply artificial intelligence to the problem of on-board fault management. The goal of this work is to develop fault management systems. This presentation will discuss work in progress at TRW to apply artificial intelligence to the problem of on-board fault management. The goal of this work is to develop fault management systems that can meet the needs of spacecraft that have long-range autonomy requirements. We have implemented a model-based approach to fault detection and isolation that does not require explicit characterization of failures prior to launch. It is thus able to detect failures that were not considered in the failure and effects analysis. We have applied this technique to several different subsystems and tested our approach against both simulations and an electrical power system hardware testbed. We present findings from simulation and hardware tests which demonstrate the ability of our model-based system to detect and isolate failures, and describe our work in porting the Ada version of this system to a flight-qualified processor. We also discuss current research aimed at expanding our system to monitor the entire spacecraft.

ROSE: the road simulation environment

NASA Astrophysics Data System (ADS)

Liatsis, Panos; Mitronikas, Panogiotis

1997-05-01

Evaluation of advanced sensing systems for autonomous vehicle navigation (AVN) is currently carried out off-line with prerecorded image sequences taken by physically attaching the sensors to the ego-vehicle. The data collection process is cumbersome and costly as well as highly restricted to specific road environments and weather conditions. This work proposes the use of scientific animation in modeling and representation of real-world traffic scenes and aims to produce an efficient, reliable and cost-effective concept evaluation suite for AVN sensing algorithms. ROSE is organized in a modular fashion consisting of the route generator, the journey generator, the sequence description generator and the renderer. The application was developed in MATLAB and POV-Ray was selected as the rendering module. User-friendly graphical user interfaces have been designed to allow easy selection of animation parameters and monitoring of the generation proces. The system, in its current form, allows the generation of various traffic scenarios, providing for an adequate number of static/dynamic objects, road types and environmental conditions. Initial tests on the robustness of various image processing algorithms to varying lighting and weather conditions have been already carried out.

A mathematical model for simulating noise suppression of lined ejectors

NASA Technical Reports Server (NTRS)

Watson, Willie R.

1994-01-01

A mathematical model containing the essential features embodied in the noise suppression of lined ejectors is presented. Although some simplification of the physics is necessary to render the model mathematically tractable, the current model is the most versatile and technologically advanced at the current time. A system of linearized equations and the boundary conditions governing the sound field are derived starting from the equations of fluid dynamics. A nonreflecting boundary condition is developed. In view of the complex nature of the equations, a parametric study requires the use of numerical techniques and modern computers. A finite element algorithm that solves the differential equations coupled with the boundary condition is then introduced. The numerical method results in a matrix equation with several hundred thousand degrees of freedom that is solved efficiently on a supercomputer. The model is validated by comparing results either with exact solutions or with approximate solutions from other works. In each case, excellent correlations are obtained. The usefulness of the model as an optimization tool and the importance of variable impedance liners as a mechanism for achieving broadband suppression within a lined ejector are demonstrated.

Fuel sensor-less control of a liquid feed fuel cell under dynamic loading conditions for portable power sources (II)

NASA Astrophysics Data System (ADS)

Chang, C. L.; Chen, C. Y.; Sung, C. C.; Liou, D. H.; Chang, C. Y.; Cha, H. C.

This work presents a new fuel sensor-less control scheme for liquid feed fuel cells that is able to control the supply to a fuel cell system for operation under dynamic loading conditions. The control scheme uses cell-operating characteristics, such as potential, current, and power, to regulate the fuel concentration of a liquid feed fuel cell without the need for a fuel concentration sensor. A current integral technique has been developed to calculate the quantity of fuel required at each monitoring cycle, which can be combined with the concentration regulating process to control the fuel supply for stable operation. As verified by systematic experiments, this scheme can effectively control the fuel supply of a liquid feed fuel cell with reduced response time, even under conditions where the membrane electrolyte assembly (MEA) deteriorates gradually. This advance will aid the commercialization of liquid feed fuel cells and make them more adaptable for use in portable and automotive power units such as laptops, e-bikes, and handicap cars.

Performance costs when emotion tunes inappropriate cognitive abilities: implications for mental resources and behavior.

PubMed

Storbeck, Justin

2012-08-01

Emotion tunes cognition, such that approach-motivated positive states promote verbal cognition, whereas withdrawal-motivated negative states promote spatial cognition (Gray, 2001). The current research examined whether self-control resources become depleted and influence subsequent behavior when emotion tunes an inappropriate cognitive tendency. In 2 experiments, either an approach-motivated positive state or a withdrawal-motivated negative state was induced, and then participants completed a verbal or a spatial working memory task creating conditions of emotion-cognition alignment (e.g., approach/verbal) or misalignment (e.g., approach/spatial). A control condition was also included. To examine behavioral costs due to depleted self-control resources, participants completed either a Stroop task (Stroop, 1935; Experiment 1) or a Black/White implicit association test (IAT; Greenwald, McGhee, & Schwartz, 1998; Experiment 2). Participants in the misalignment conditions performed worse on the Stroop task, and they were worse at controlling their implicit attitude biases on the IAT. Thus, when emotion tunes inappropriate cognitive tendencies for one's current environment, self-control resources become depleted, impairing behavioral control. (PsycINFO Database Record (c) 2012 APA, all rights reserved).

Enhancement of Operating Efficiency Of The Central Coal-Preparation Plant of "MMK - UGOL" Ltd. Under Current Conditions

NASA Astrophysics Data System (ADS)

Basarygin, Maksim

2017-11-01

In this article the subject of enhancement of operating efficiency of the central coal-preparation plant of OOO "MMK-UGOL" is encompassed. Modern trends in the development of technologies and equipment for coal beneficiation are due to the following requirements: improving competitiveness of coal products, improvement of quality of marketable products, reduction of coal production cost, environmental requirements: polluting emission abatement, prepared coal saving, improvement of the effectiveness of resource conservation; complex mechanization and beneficiation process automation. In the article the contemporary problems of raw coal benefication under current conditions of the increased dilution of withdrawable coals with rock fractions are considered. Comparative analysis of efficiency of application of modern concentrating equipment under the conditions of the CCPP of OOO "MMK-UGOL" is carried out on the basis of research works. Particular attention is paid to dehydration of produced coal concentrate with content of volatile agents of more than 35.0% and content of fine-dispersed particles in flotation concentrate of more than 50.0%. Comparative analysis of the coal concentrate dehydration technologies is conducted.

Criminalisation of clients: reproducing vulnerabilities for violence and poor health among street-based sex workers in Canada-a qualitative study.

PubMed

Krüsi, A; Pacey, K; Bird, L; Taylor, C; Chettiar, J; Allan, S; Bennett, D; Montaner, J S; Kerr, T; Shannon, K

2014-06-02

To explore how criminalisation and policing of sex buyers (clients) rather than sex workers shapes sex workers' working conditions and sexual transactions including risk of violence and HIV/sexually transmitted infections (STIs). Qualitative and ethnographic study triangulated with sex work-related violence prevalence data and publicly available police statistics. Vancouver, Canada, provides a unique opportunity to evaluate the impact of policies that criminalise clients as the local police department adopted a sex work enforcement policy in January 2013 that prioritises sex workers' safety over arrest, while continuing to target clients. 26 cisgender and 5 transgender women who were street-based sex workers (n=31) participated in semistructured interviews about their working conditions. All had exchanged sex for money in the previous 30 days in Vancouver. Thematic analysis of interview transcripts and ethnographic field notes focused on how police enforcement of clients shaped sex workers' working conditions and sexual transactions, including risk of violence and HIV/STIs, over an 11-month period postpolicy implementation (January-November 2013). Sex workers' narratives and ethnographic observations indicated that while police sustained a high level of visibility, they eased charging or arresting sex workers and showed increased concern for their safety. However, participants' accounts and police statistics indicated continued police enforcement of clients. This profoundly impacted the safety strategies sex workers employed. Sex workers continued to mistrust police, had to rush screening clients and were displaced to outlying areas with increased risks of violence, including being forced to engage in unprotected sex. These findings suggest that criminalisation and policing strategies that target clients reproduce the harms created by the criminalisation of sex work, in particular, vulnerability to violence and HIV/STIs. The current findings support decriminalisation of sex work to ensure work conditions that support the health and safety of sex workers in Canada and globally. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Low Current Surface Flashover for Initiation of Electric Propulsion Devices

NASA Astrophysics Data System (ADS)

Dary, Omar G.

There has been a recent increase in interest in miniaturization of propulsion systems for satellites. These systems are needed to propel micro- and nano-satellites, where platforms are much smaller than conventional satellites and require smaller levels of thrust. Micro-propulsion systems for these satellites are in their infancy and they must manage with smaller power systems and smaller propellant volumes. Electric propulsion systems operating on various types of electric discharges are typically used for these needs. One of the central components of such electrical micropropulsion systems are ignitor subsystems, which are required for creation the breakdown and initiation of the main discharge. Ignitors have to provide reliable ignition for entire lifetime of the micropropulsion system. Electric breakdown in vacuum usually require high voltage potentials of hundreds of kilovolts per mm to induce breakdown. The breakdown voltage can be significantly decreased (down to several kVs per mm) if dielectric surface flashover is utilized. However, classical dielectric surface flashover operates at large electric current (100s of Amperes) and associated with overheating and damage of the electrodes/dielectric assembly after several flashover events. The central idea of this work was to eliminate the damage to the flashover electrode assembly by limiting the flashover currents to low values in milliampere range (Low Current Surface Flashover -LCSF) and utilize LCSF system as an ignition source for the main discharge on the micropropulsion system. The main objective of this research was to create a robust LCSF ignition system, capable producing a large number of surface flashover triggering events without significant damage to the LCSF electrode assembly. The thesis aims to characterize the plasma plume created at LCSF, study electrodes ablation and identify conditions required for robust triggering of main discharge utilized on micro-propulsion system. Conditioning of a new LCSF assembly (flashover current was limited to <100 mA in all experiments) was measured and breakdown voltages in the range of 8kV to 12kV were observed for the fully conditioned assembly. No damage to the LCSF electrode assembly was observed after about 104 LCSF events. The LCSF assembly created sufficient amount of seed plasma in order to bridge a vacuum gap between the high-current electrodes and to reliably ignite high-current arcs (10A-12A arc were used in this work). Ignition of the high-current arc was observed at three different cases of LCSF with limiting currents 100 mA, 33 mA and 20 mA respectively. Plasma parameter measurements were conducted with variety of Langmuir probes inside the LCSF plume. Ion currents created by the LCSF were primarily expelled directly perpendicular from the insulator surface. The plasma expansion for the LCSF assembly was measured to be 2 x 106-6 x 106 cm/s. Plasma density was measured to range 10 10-1011 cm-3. The plasma density was maximal near the LCSF assembly and quickly reduced radially. Temporal decay of the plasma was observed on a time scale of about 5 micros after the LCSF event. The results of this work are significant for creation of ignitor for micropropulsion systems. LCSF system offers reliable triggering for numerous ignition pulses for entire lifetime of the micropropulsion system and reduces complexity and volume of the system by excluding moving parts and the need for an external gas tanks.

The research subject as wage earner.

PubMed

Anderson, James A; Weijer, Charles

2002-01-01

The practice of paying research subjects for participating in clinical trials has yet to receive an adequate moral analysis. Dickert and Grady argue for a wage payment model in which research subjects are paid an hourly wage based on that of unskilled laborers. If we accept this approach, what follows? Norms for just working conditions emerge from workplace legislation and political theory. All workers, including paid research subjects under Dickert and Grady's analysis, have a right to at least minimum wage, a standard work week, extra pay for overtime hours, a safe workplace, no fault compensation for work-related injury, and union organization. If we accept that paid research subjects are wage earners like any other, then the implications for changes to current practice are substantial.

Operational Analysis in the Launch Environment

NASA Technical Reports Server (NTRS)

James, George; Kaouk, Mo; Cao, Tim; Fogt, Vince; Rocha, Rodney; Schultz, Ken; Tucker, Jon-Michael; Rayos, Eli; Bell,Jeff; Alldredge, David;

Transcranial Direct Current Stimulation Improves Executive Dysfunctions in ADHD: Implications for Inhibitory Control, Interference Control, Working Memory, and Cognitive Flexibility.

PubMed

Nejati, Vahid; Salehinejad, Mohammad Ali; Nitsche, Michael A; Najian, Asal; Javadi, Amir-Homayoun

2017-09-01

This study examined effects of transcranial direct current stimulation (tDCS) over the dorsolateral prefrontal cortex (DLPFC) and orbitofrontal cortex (OFC) on major executive functions (EFs), including response inhibition, executive control, working memory (WM), and cognitive flexibility/task switching in ADHD. ADHD children received (a) left anodal/right cathodal DLPFC tDCS and (b) sham stimulation in Experiment 1 and (a) left anodal DLPFC/right cathodal OFC tDCS, (b) left cathodal DLPFC/right anodal OFC tDCS, and (c) sham stimulation in Experiment 2. The current intensity was 1 mA for 15 min with a 72-hr interval between sessions. Participants underwent Go/No-Go task, N-back test, Wisconsin Card Sorting Test (WCST), and Stroop task after each tDCS condition. Anodal left DLPFC tDCS most clearly affected executive control functions (e.g., WM, interference inhibition), while cathodal left DLPFC tDCS improved inhibitory control. Cognitive flexibility/task switching benefited from combined DLPFC-OFC, but not DLPFC stimulation alone. Task-specific stimulation protocols can improve EFs in ADHD.

Update on developments at SNIF

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zacks, J., E-mail: jamie.zacks@ccfe.ac.uk; Turner, I.; Day, I.

The Small Negative Ion Facility (SNIF) at CCFE has been undergoing continuous development and enhancement to both improve operational reliability and increase diagnostic capability. SNIF uses a CW 13.56MHz, 5kW RF driven volume source with a 30kV triode accelerator. Improvement and characterisation work includes: Installation of a new “L” type RF matching unit, used to calculate the load on the RF generator. Use of the electron suppressing biased insert as a Langmuir probe under different beam extraction conditions. Measurement of the hydrogen Fulcher molecular spectrum, used to calculate gas temperature in the source. Beam optimisation through parameter scans, using coppermore » target plate and visible cameras, with results compared with AXCEL-INP to provide beam current estimate. Modelling of the beam power density profile on the target plate using ANSYS to estimate beam power and provide another estimate of beam current. This work is described, and has allowed an estimation of the extracted beam current of approximately 6mA (4mA/cm2) at 3.5kW RF power and a source pressure of 0.6Pa.« less

Impact of typical steady-state conditions and transient conditions on flow ripple and its test accuracy for axial piston pump

NASA Astrophysics Data System (ADS)

Xu, Bing; Hu, Min; Zhang, Junhui

2015-09-01

The current research about the flow ripple of axial piston pump mainly focuses on the effect of the structure of parts on the flow ripple. Therein, the structure of parts are usually designed and optimized at rated working conditions. However, the pump usually has to work in large-scale and time-variant working conditions. Therefore, the flow ripple characteristics of pump and analysis for its test accuracy with respect to variant steady-state conditions and transient conditions in a wide range of operating parameters are focused in this paper. First, a simulation model has been constructed, which takes the kinematics of oil film within friction pairs into account for higher accuracy. Afterwards, a test bed which adopts Secondary Source Method is built to verify the model. The simulation and tests results show that the angular position of the piston, corresponding to the position where the peak flow ripple is produced, varies with the different pressure. The pulsating amplitude and pulsation rate of flow ripple increase with the rise of pressure and the variation rate of pressure. For the pump working at a constant speed, the flow pulsation rate decreases dramatically with the increasing speed when the speed is less than 27.78% of the maximum speed, subsequently presents a small decrease tendency with the speed further increasing. With the rise of the variation rate of speed, the pulsating amplitude and pulsation rate of flow ripple increase. As the swash plate angle augments, the pulsating amplitude of flow ripple increases, nevertheless the flow pulsation rate decreases. In contrast with the effect of the variation of pressure, the test accuracy of flow ripple is more sensitive to the variation of speed. It makes the test accuracy above 96.20% available for the pulsating amplitude of pressure deviating within a range of ±6% from the mean pressure. However, with a variation of speed deviating within a range of ±2% from the mean speed, the attainable test accuracy of flow ripple is above 93.07%. The model constructed in this research proposes a method to determine the flow ripple characteristics of pump and its attainable test accuracy under the large-scale and time-variant working conditions. Meanwhile, a discussion about the variation of flow ripple and its obtainable test accuracy with the conditions of the pump working in wide operating ranges is given as well.

Development of Surface Mechanical Attrition Treatment (SMAT) and Electrodeposition Process for Generating Nanostructured Materials and Study of Their Tensile Properties

NASA Astrophysics Data System (ADS)

Chan, Hoi Lam

This work systematically investigates two of the most promising synthesis methods for producing nanostructured (NS) materials: surface mechanical attrition treatment (SMAT) and the electrodeposition (ED) process, and obtains the proper conditions for fabricating NS materials in bulk form and studies the properties of these materials. SMAT is one of the recently developed processes to form nano-crystallized surface layer and refine grains in the subsurface layers, by actuating a number of spherical projectiles to impact the sample surface. In this work, the detailed measurement of ball impinging velocity is presented, and the resulted strain-rate and strains are theoretically modeled. Consequently the relation between plastic strain history and the observed microstructures is established. The SMAT process with different numbers of balls is explored to manifest that an optimum number of balls exists for the highest efficiency. ED process is widely used in producing NS materials these days. In this work, the relationships among non-metallic substrates, current type, current densities, microstructure and crystallographic textures, and mechanical properties is presented in order to demonstrate the influences of the deposition parameters in obtaining nano-grains and nano-twins microstructures. This work also examines the availability of obtaining bulk NS materials with desirable ductility in production-scale conditions through understanding these relationships. In the last part of the study, the effect of SMAT on the electrodeposits is studied. Tensile properties, microstructures and textures of the SMATed electrodeposits have been examined. The results demonstrate that the NS matrix obtained by the ED process with sufficient thickness retains desirable ductility after employing SMAT technology, and the SMAT process further enhances the strength of the electrodeposits.

The Exchange Relationship between Work-Family Enrichment and Affective Commitment: the Moderating Role of Gender.

PubMed

Marques, António Manuel; Chambel, Maria José; Pinto, Inês

2015-06-03

Workers' perception that their job experience enriches their family life has been considered a mechanism that explains their positive attitudes toward the organization where they work. However, because women and men live their work and family differently, gender may condition this relationship between the work-family enrichment and workers' attitudes. With a sample of 1885 workers from one Portuguese bank, with 802 women, the current study investigated the relationship between work-family enrichment and organizational affective commitment as well as the role of sex as a moderator of this relationship. The hypotheses were tested by using regression analysis. The results indicated that the perception held by workers that their work enriches their family is positively correlated with their affective commitment toward the organization. Furthermore, the data revealed that this relationship is stronger for women than for men. Study results have implications for management, particularly for human resource management, enhancing their knowledge about the relationship of work-family enrichment and workers' affective commitment toward organization.

Soil moisture observations using L-, C-, and X-band microwave radiometers

NASA Astrophysics Data System (ADS)

Bolten, John Dennis

The purpose of this thesis is to further the current understanding of soil moisture remote sensing under varying conditions using L-, C-, and X-band. Aircraft and satellite instruments are used to investigate the effects of frequency and spatial resolution on soil moisture sensitivity. The specific objectives of the research are to examine multi-scale observed and modeled microwave radiobrightness, evaluate new EOS Aqua Advanced Microwave Scanning Radiometer (AMSR-E) brightness temperature and soil moisture retrievals, and examine future satellite-based technologies for soil moisture sensing. The cycling of Earth's water, energy and carbon is vital to understanding global climate. Over land, these processes are largely dependent on the amount of moisture within the top few centimeters of the soil. However, there are currently no methods available that can accurately characterize Earth's soil moisture layer at the spatial scales or temporal resolutions appropriate for climate modeling. The current work uses ground truth, satellite and aircraft remote sensing data from three large-scale field experiments having different land surface, topographic and climate conditions. A physically-based radiative transfer model is used to simulate the observed aircraft and satellite measurements using spatially and temporally co-located surface parameters. A robust analysis of surface heterogeneity and scaling is possible due to the combination of multiple datasets from a range of microwave frequencies and field conditions. Accurate characterization of spatial and temporal variability of soil moisture during the three field experiments is achieved through sensor calibration and algorithm validation. Comparisons of satellite observations and resampled aircraft observations are made using soil moisture from a Numerical Weather Prediction (NWP) model in order to further demonstrate a soil moisture correlation where point data was unavailable. The influence of vegetation, spatial scaling, and surface heterogeneity on multi-scale soil moisture prediction is presented. This work demonstrates that derived soil moisture using remote sensing provides a better coverage of soil moisture spatial variability than traditional in-situ sensors. Effects of spatial scale were shown to be less significant than frequency on soil moisture sensitivity. Retrievals of soil moisture using the current methods proved inadequate under some conditions; however, this study demonstrates the need for concurrent spaceborne frequencies including L-, C, and X-band.

ASSESSMENT OF DYNAMIC PRA TECHNIQUES WITH INDUSTRY AVERAGE COMPONENT PERFORMANCE DATA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yadav, Vaibhav; Agarwal, Vivek; Gribok, Andrei V.

In the nuclear industry, risk monitors are intended to provide a point-in-time estimate of the system risk given the current plant configuration. Current risk monitors are limited in that they do not properly take into account the deteriorating states of plant equipment, which are unit-specific. Current approaches to computing risk monitors use probabilistic risk assessment (PRA) techniques, but the assessment is typically a snapshot in time. Living PRA models attempt to address limitations of traditional PRA models in a limited sense by including temporary changes in plant and system configurations. However, information on plant component health are not considered. Thismore » often leaves risk monitors using living PRA models incapable of conducting evaluations with dynamic degradation scenarios evolving over time. There is a need to develop enabling approaches to solidify risk monitors to provide time and condition-dependent risk by integrating traditional PRA models with condition monitoring and prognostic techniques. This paper presents estimation of system risk evolution over time by integrating plant risk monitoring data with dynamic PRA methods incorporating aging and degradation. Several online, non-destructive approaches have been developed for diagnosing plant component conditions in nuclear industry, i.e., condition indication index, using vibration analysis, current signatures, and operational history [1]. In this work the component performance measures at U.S. commercial nuclear power plants (NPP) [2] are incorporated within the various dynamic PRA methodologies [3] to provide better estimates of probability of failures. Aging and degradation is modeled within the Level-1 PRA framework and is applied to several failure modes of pumps and can be extended to a range of components, viz. valves, generators, batteries, and pipes.« less

Canceling buoyancy of gaseous fuel flames in a gravitational environment using an ion-driven wind.

PubMed

Papac, M J; Dunn-Rankin, D

2006-09-01

Electric fields applied to combustion plasmas can be used to manipulate the thermofluid flow field to reduce buoyant forces and, hence, convection in locations near and within the flame. The resulting flow field is similar to that which is obtained in microgravity. Previous work has shown that buoyancy is modified in a non-premixed methane-air capillary flame when it burns in a capillary-to-plane configuration and an electric field is applied, and that regions of neutral or microbuoyancy exist, as indicated by the examined temperature and oxidizer profiles. The aim of this article is to examine in more detail this microbuoyancy condition and the coupling between the ion wind and resulting thermofluid flow field. To this end, the voltage-current characteristics (VCC) of CH4, C2H2, C2H4, C2H6, and C3H8 are measured and compared. Soot generated in the C2H(X) and propane flames lead to a hysteresis in the VCC curve whereby increased sooting leads to lower ion currents at constant flow rates and applied potentials. Buoyancy regimes for these flames in this configuration are determined. Methane can achieve the highest flow rate without sooting at the microbuoyant condition, and does not exhibit hysteresis in the VCC for the flow rates examined here. Furthermore, in this geometry, the microbuoyant condition for methane is found to coincide with ion current saturation when the capillary-to-plane distance is varied. These results allow for several simplifications to be made when modeling the flame at these conditions: the imposition of a spherical flame boundary with known ion current, and negligible recombination in the domain.

Impact of Climate Conditions on Occupational Health and Related Economic Losses: A New Feature of Global and Urban Health in the Context of Climate Change.

PubMed

Kjellstrom, Tord

2016-03-01

One feature of climate change is the increasing heat exposure in many workplaces where efficient cooling systems cannot be applied. Excessive heat exposure is a particular problem for working people because of the internal heat production when muscle work is carried out. The physiological basis for severe heat stroke, other clinical effects, and heat exhaustion is well known. One feature of this health effect of excessive workplace heat exposure is reduced work capacity, and new research has started to quantify this effect in the context of climate change. Current climate conditions in tropical and subtropical parts of the world are already so hot during the hot seasons that occupational health effects occur and work capacity for many working people is affected. The Hothaps-Soft database and software andClimateCHIP.orgwebsite make it possible to rapidly produce estimates of local heat conditions and trends. The results can be mapped to depict the spatial distribution of workplace heat stress. In South-East Asia as much as 15% to 20% of annual work hours may already be lost in heat-exposed jobs, and this may double by 2050 as global climate change progresses. By combining heat exposure data and estimates of the economic consequences, the vulnerability of many low- and middle-income countries is evident. The annual cost of reduced labor productivity at country level already in 2030 can be several percent of GDP, which means billions of US dollars even for medium-size countries. The results provide new arguments for effective climate change adaptation and mitigation policies and preventive actions in all countries. © 2015 APJPH.

Can psychosocial work conditions protect against age-related cognitive decline? Results from a systematic review

PubMed Central

Nexø, Mette Andersen; Meng, Annette; Borg, Vilhelm

2016-01-01

According to the use it or lose it hypothesis, intellectually stimulating activities postpone age-related cognitive decline. A previous systematic review concluded that a high level of mental work demands and job control protected against cognitive decline. However, it did not distinguish between outcomes that were measured as cognitive function at one point in time or as cognitive decline. Our study aimed to systematically review which psychosocial working conditions were prospectively associated with high levels of cognitive function and/or changes in cognitive function over time. Articles were identified by a systematic literature search (MEDLINE, Web of Science (WOS), PsycNET, Occupational Safety and Health (OSH)). We included only studies with longitudinal designs examining the impact of psychosocial work conditions on outcomes defined as cognitive function or changes in cognitive function. Two independent reviewers compared title-abstract screenings, full-text screenings and quality assessment ratings. Eleven studies were included in the final synthesis and showed that high levels of mental work demands, occupational complexity or job control at one point in time were prospectively associated with higher levels of cognitive function in midlife or late life. However, the evidence to clarify whether these psychosocial factors also affected cognitive decline was insufficient, conflicting or weak. It remains speculative whether job control, job demands or occupational complexity can protect against cognitive decline. Future studies using methodological advancements can reveal whether workers gain more cognitive reserve in midlife and late life than the available evidence currently suggests. The public health implications of a previous review should thereby be redefined accordingly. PMID:27178844

Do Working Memory Deficits Underlie Reading Problems in Attention-Deficit/Hyperactivity Disorder (ADHD)?

PubMed

Kofler, Michael J; Spiegel, Jamie A; Soto, Elia F; Irwin, Lauren N; Wells, Erica L; Austin, Kristin E

2018-06-19

Reading problems are common in children with ADHD and show strong covariation with these children's underdeveloped working memory abilities. In contrast, working memory training does not appear to improve reading performance for children with ADHD or neurotypical children. The current study bridges the gap between these conflicting findings, and combines dual-task methodology with Bayesian modeling to examine the role of working memory for explaining ADHD-related reading problems. Children ages 8-13 (M = 10.50, SD = 1.59) with and without ADHD (N = 78; 29 girls; 63% Caucasian/Non-Hispanic) completed a counterbalanced series of reading tasks that systematically manipulated concurrent working memory demands. Adding working memory demands produced disproportionate decrements in reading comprehension for children with ADHD (d = -0.67) relative to Non-ADHD children (d = -0.18); comprehension was significantly reduced in both groups when working memory demands were increased. These effects were robust to controls for foundational reading skills (decoding, sight word vocabulary) and comorbid reading disability. Concurrent working memory demands did not slow reading speed for either group. The ADHD group showed lower comprehension (d = 1.02) and speed (d = 0.69) even before adding working memory demands beyond those inherently required for reading. Exploratory conditional effects analyses indicated that underdeveloped working memory overlapped with 41% (comprehension) and 85% (speed) of these between-group differences. Reading problems in ADHD appear attributable, at least in part, to their underdeveloped working memory abilities. Combined with prior cross-sectional and longitudinal findings, the current experimental evidence positions working memory as a potential causal mechanism that is necessary but not sufficient for effectively understanding written language.

Correlations between properties and applications of the CVD amorphous silicon carbide films

NASA Astrophysics Data System (ADS)

Kleps, Irina; Angelescu, Anca

2001-12-01

The aim of this paper is to emphasise the correlation between film preparation conditions, film properties and their applications. Low pressure chemical vapour deposition amorphous silicon carbide (a-SiC) and silicon carbonitride (SiCN) films obtained from liquid precursors have different structure and composition depending on deposition conditions. Thus, the films deposited under kinetic working conditions reveal a stable structure and composition. Deposition at moderate temperature leads to stoichiometric SiC, while the films deposited at high temperatures have a composition closer to Si 1- xC x, with x=0.75. These films form a very reactive interface with metallic layers. The films realised under kinetic working regime can be used in Si membrane fabrication process or as coating films for field emission applications. SiC layers field emission properties were investigated; the field emission current density of the a-SiC/Si structures was 2.4 mA/cm 2 at 25 V/μm. An Si membrane technology based on moderate temperatures (770-850 °C) a-SiC etching mask is presented.

Constant-current corona triode adapted and optimized for the characterization of thin dielectric films

NASA Astrophysics Data System (ADS)

Giacometti, José A.

2018-05-01

This work describes an enhanced corona triode with constant current adapted to characterize the electrical properties of thin dielectric films used in organic electronic devices. A metallic grid with a high ionic transparency is employed to charge thin films (100 s of nm thick) with a large enough charging current. The determination of the surface potential is based on the grid voltage measurement, but using a more sophisticated procedure than the previous corona triode. Controlling the charging current to zero, which is the open-circuit condition, the potential decay can be measured without using a vibrating grid. In addition, the electric capacitance and the characteristic curves of current versus the stationary surface potential can also be determined. To demonstrate the use of the constant current corona triode, we have characterized poly(methyl methacrylate) thin films with films with thicknesses in the range from 300 to 500 nm, frequently used as gate dielectric in organic field-effect transistors.

Evaluation Tools in the European Higher Education Area (EHEA): An Assessment for Evaluating the Competences of the Final Year Project in the Social Sciences

ERIC Educational Resources Information Center

Mateo, Joan; Escofet, Anna; Martinez-Olmo, Francesc; Ventura, Javier; Vlachopoulos, Dimitrios

2012-01-01

The guidelines of the European Higher Education Area (EHEA) imply the rethinking of many of the current evaluation systems, since the new pedagogical models now focus on the learning acquired through the students' personal work and on the establishment of the ideal conditions for them to achieve the learning outcomes of the proposed educational…

Symbolic Model of Perception in Dynamic 3D Environments

DTIC Science & Technology

2006-11-01

can retrieve memories , work on goals, recognize visual or aural percepts, and perform actions. ACT-R has been selected for the current...types of memory . Procedural memory is the store of condition- action productions that are selected and executed by the core production system...a declarative memory chunk that is made available to the core production system through the vision module . 4 The vision module has been

Assessing the shielding of engine noise by the wings for current aircraft using model predictions and measurements.

PubMed

Vieira, Ana; Snellen, Mirjam; Simons, Dick G

2018-01-01

Reducing aircraft noise is a major issue to be dealt with by the aerospace industry. In addition to lowering noise emissions from the engine and airframe, also the shielding of engine noise by the aircraft is considered as a promising means for reducing the perceived noise on the ground. In literature, noise shielding predictions indicate significant reductions in received noise levels for blended wing body configurations, but also for conventional aircraft with the engines placed above the wings. Little work has been done in assessing these potential shielding effects for full aircraft under real operational conditions. Therefore, in this work, noise shielding for current aircraft is investigated using both measurements and model predictions. The predictions are based on the Kirchhoff integral theory and the Modified Theory of Physical Optics. For the comparison between the predictions and measurements, Twenty Fokker 70 flyovers are considered. The data analysis approach for the extraction of shielding levels for aircraft under these operational conditions is presented. Directly under the flight path, the simulations predict an engine noise shielding of 6 dB overall sound pressure level. This is confirmed by some of the flyover data. On average, the measurements show somewhat lower shielding levels.

[IR spectral-analysis-based range estimation for an object with small temperature difference from background].

PubMed

Fu, Xiao-Ning; Wang, Jie; Yang, Lin

2013-01-01

It is a typical passive ranging technology that estimation of distance of an object is based on transmission characteristic of infrared radiation, it is also a hotspot in electro-optic countermeasures. Because of avoiding transmitting energy in the detection, this ranging technology will significantly enhance the penetration capability and infrared conceal capability of the missiles or unmanned aerial vehicles. With the current situation in existing passive ranging system, for overcoming the shortage in ranging an oncoming target object with small temperature difference from background, an improved distance estimation scheme was proposed. This article begins with introducing the concept of signal transfer function, makes clear the working curve of current algorithm, and points out that the estimated distance is not unique due to inherent nonlinearity of the working curve. A new distance calculation algorithm was obtained through nonlinear correction technique. It is a ranging formula by using sensing information at 3-5 and 8-12 microm combined with background temperature and field meteorological conditions. The authors' study has shown that the ranging error could be mainly kept around the level of 10% under the condition of the target and background apparent temperature difference equal to +/- 5 K, and the error in estimating background temperature is no more than +/- 15 K.

Offline detection of broken rotor bars in AC induction motors

NASA Astrophysics Data System (ADS)

Powers, Craig Stephen

ABSTRACT. OFFLINE DETECTION OF BROKEN ROTOR BARS IN AC INDUCTION MOTORS. The detection of the broken rotor bar defect in medium- and large-sized AC induction machines is currently one of the most difficult tasks for the motor condition and monitoring industry. If a broken rotor bar defect goes undetected, it can cause a catastrophic failure of an expensive machine. If a broken rotor bar defect is falsely determined, it wastes time and money to physically tear down and inspect the machine only to find an incorrect diagnosis. Previous work in 2009 at Baker/SKF-USA in collaboration with the Korea University has developed a prototype instrument that has been highly successful in correctly detecting the broken rotor bar defect in ACIMs where other methods have failed. Dr. Sang Bin and his students at the Korea University have been using this prototype instrument to help the industry save money in the successful detection of the BRB defect. A review of the current state of motor conditioning and monitoring technology for detecting the broken rotor bar defect in ACIMs shows improved detection of this fault is still relevant. An analysis of previous work in the creation of this prototype instrument leads into the refactoring of the software and hardware into something more deployable, cost effective and commercially viable.

Resonant Raman scattering background in XRF spectra of binary samples

NASA Astrophysics Data System (ADS)

Sánchez, Héctor Jorge; Leani, Juan José

2015-02-01

In x-ray fluorescence analysis, spectra present singular characteristics produced by the different scattering processes. When atoms are irradiated with incident energy lower and close to an absorption edge, scattering peaks appear due to an inelastic process known as resonant Raman scattering. In this work we present theoretical calculations of the resonant Raman scattering contributions to the background of x-ray fluorescence spectra of binary samples of current technological or biological interest. On one hand, a binary alloy of Fe with traces of Mn (Mn: 0.01%, Fe: 99.99%) was studied because of its importance in the stainless steels industries. On the second hand a pure sample of Ti with V traces (Ti: 99%, V: 1%) was analyzed due to the current relevance in medical applications. In order to perform the calculations the Shiraiwa and Fujino's model was used to calculate characteristic intensities and scattering interactions. This model makes certain assumptions and approximations to achieve the calculations, especially in the case of the geometrical conditions and the incident and take-off beams. For the binary sample studied in this work and the considered experimental conditions, the calculations show that the resonant Raman scattering background is significant under the fluorescent peak, affects the symmetry of the peaks and, depending on the concentrations, overcomes the enhancements contributions (secondary fluorescence).

Contextual and Auditory Fear Conditioning Continue to Emerge during the Periweaning Period in Rats

PubMed Central

Burman, Michael A.; Erickson, Kristen J.; Deal, Alex L.; Jacobson, Rose E.

2014-01-01

Anxiety disorders often emerge during childhood. Rodent models using classical fear conditioning have shown that different types of fear depend upon different neural structures and may emerge at different stages of development. For example, some work has suggested that contextual fear conditioning generally emerges later in development (postnatal day 23–24) than explicitly cued fear conditioning (postnatal day 15–17) in rats. This has been attributed to an inability of younger subjects to form a representation of the context due to an immature hippocampus. However, evidence that contextual fear can be observed in postnatal day 17 subjects and that cued fear conditioning continues to emerge past this age raises questions about the nature of this deficit. The current studies examine this question using both the context pre-exposure facilitation effect for immediate single-shock contextual fear conditioning and traditional cued fear conditioning using Sprague-Dawley rats. The data suggest that both cued and contextual fear conditioning are continuing to develop between PD 17 and 24, consistent with development occurring the in essential fear conditioning circuit. PMID:24977415

Factors related to the continuation of employment during pregnancy among Japanese women.

PubMed

Matsuzaki, Masayo; Haruna, Megumi; Ota, Erika; Murayama, Ryoko; Murashima, Sachiyo

2011-12-01

To determine the relationship between the working situation (full-time housewife, stopped working during pregnancy, or currently employed) and the lifestyle factors, reasons for stopping work during pregnancy, and effects of working conditions in order to identify the factors that are related to the continuation of employment among pregnant Japanese women. In a cross-sectional study, a questionnaire was administered to pregnant women who visited an obstetrics clinic in a Tokyo suburb for an outpatient medical check-up during July and August 2004. The data of 530 healthy pregnant women were analyzed. The pregnant women who stopped working during their pregnancy had lower mental health scores than the full-time housewives and employed pregnant women. In each trimester, the employed pregnant women reported a shorter daytime sleep duration than the pregnant women who stopped working during their pregnancy and the full-time housewives. The reasons for stopping work during pregnancy were categorized as somatic symptoms due to pregnancy, working conditions, and a sense of values or social reasons. The employed women in the third trimester more often reported the availability of, and access to, a rest area in their company, compared to those in the first and second trimesters. The lifestyle factors of the pregnant women were different, based on their work situation. In particular, the employed pregnant women had a shorter daytime sleep duration. The pregnant women who stopped working during their pregnancy could have benefited from mental health support. In addition, the reasons for stopping work during pregnancy were different in the three trimesters. A flexible system is needed for working women that adapts to the physical changes that occur during pregnancy. © 2011 The Authors. Japan Journal of Nursing Science © 2011 Japan Academy of Nursing Science.

Self-pulsing discharge of a plasma brush operated in atmospheric-pressure argon

NASA Astrophysics Data System (ADS)

Li, Xuechen; Liu, Runfu; Jia, Pengying; Bao, Wenting; Shang, Yong

2013-06-01

A plasma brush excited by DC voltage is developed with argon as working gas in the ambient air. The time evolution of the discharge current, the light emission, and the sustaining voltage are analyzed under different conditions. The self-pulsing phenomenon of the discharge is observed with oscillated voltage and intermittent current. The self-pulsing frequency ranges from several tens hertz to several hundred hertz depending on the output power and the gas flow rate. It increases with the increasing of the gas flow rate, while it decreases as the output power increases. The phenomenon is explained qualitatively based on a spatially resolved measurement about the discharge.

Experimental testing of scattering polarization models

NASA Astrophysics Data System (ADS)

Li, Wenxian; Casini, Roberto; Tomczyk, Steven; Landi Degl'Innocenti, Egidio; Marsell, Brandan

2018-06-01

We realized a laboratory experiment to study the polarization of the Na I doublet at 589.3 nm, in the presence of a magnetic field. The purpose of the experiment is to test the theory of scattering polarization for illumination conditions typical of astrophysical plasmas. This work was stimulated by solar observations of the Na I doublet that have proven particularly challenging to reproduce with current models of polarized line formation, even casting doubts on our very understanding of the physics of scattering polarization on the Sun. The experiment has confirmed the fundamental correctness of the current theory, and demonstrated that the "enigmatic'' polarization of those observations is exclusively of solar origin.

Research on resistance characteristics of YBCO tape under short-time DC large current impact

NASA Astrophysics Data System (ADS)

Zhang, Zhifeng; Yang, Jiabin; Qiu, Qingquan; Zhang, Guomin; Lin, Liangzhen

2017-06-01

Research of the resistance characteristics of YBCO tape under short-time DC large current impact is the foundation of the developing DC superconducting fault current limiter (SFCL) for voltage source converter-based high voltage direct current system (VSC-HVDC), which is one of the valid approaches to solve the problems of renewable energy integration. SFCL can limit DC short-circuit and enhance the interrupting capabilities of DC circuit breakers. In this paper, under short-time DC large current impacts, the resistance features of naked tape of YBCO tape are studied to find the resistance - temperature change rule and the maximum impact current. The influence of insulation for the resistance - temperature characteristics of YBCO tape is studied by comparison tests with naked tape and insulating tape in 77 K. The influence of operating temperature on the tape is also studied under subcooled liquid nitrogen condition. For the current impact security of YBCO tape, the critical current degradation and top temperature are analyzed and worked as judgment standards. The testing results is helpful for in developing SFCL in VSC-HVDC.

Satisfaction with organizational aspects of health care provision among Lithuanian physicians.

PubMed

Kairys, Jonas; Zebiene, Egle; Sapoka, Virginijus; Zokas, Ignas

2008-03-01

Physician satisfaction is considered an important factor influencing quality of health care provision, patient compliance, and costs to health care systems. Dissatisfaction leads to an increase in turnover of physicians and early retirement, which has a negative impact on continuity and quality of health care. Physician dissatisfaction with certain aspects of health care provision may also help to identify potential weaknesses in satisfactory functioning of health care systems. The aim of the current research project is to study the satisfaction with different organizational aspects of health care provision in Lithuania as judged by a selection of physicians. The study was conducted in Lithuania in June 2004. Physicians in randomly selected health care centers were invited to take part in the survey, 505 primary and secondary care physicians were interviewed by external interviewers during the study period. Physicians were asked to express their satisfaction on items presented in a questionnaire. The questionnaire consisted of 22 questions, evaluating different aspects of health care services - working conditions, workload, financial remuneration, organization of health care infrastructure and availability of laboratory services. Answers were presented by the 5 point Likert type scale, ranging from "very satisfied" (5) to "very dissatisfied" (1). Physicians who were most satisfied with their working conditions were working in private primary health care practices (91.1% satisfied or very satisfied), as compared with 54% of physicians working in state-owned primary care institutions and 49.7% in hospitals. Physicians working in cities and regional centers or towns were more satisfied with organizational aspects of health care services than physicians working in rural health care centers. Satisfaction with their financial remuneration showed that 74% of respondents stated they were "dissatisfied" or "very dissatisfied". While asked about potential deficiencies in their health care institutions, the most important identified by respondents in all localities was a perceived lack of financial support for these institutions. There is a significant difference in the perception of physicians in private and state health care institutions with regard to financial remuneration as well as availability of laboratory diagnostic and treatment equipment and working conditions. Based on the study findings, possibilities to increase Primary Care financing should be considered in order to improve the quality of the delivery of health care services as well as retain physicians within the health care system. Results of this study demonstrate a need of further research to quantify what could be reasonably expected from diagnostic and investigative resources to support health care in Lithuania in current economic situation.

The effect of structural empowerment and perceived organizational support on middle level nurse managers' role satisfaction.

PubMed

Patrick, Allison; Laschinger, Heather K Spence

2006-01-01

The restructuring of Canadian health care organizations during the past decade has reduced the visibility of nursing leadership. This has resulted in job conditions that have disempowered nurse managers and influenced their ability to create positive work environments, mentor potential nurse leaders, and gain satisfaction in the leadership role. These conditions threaten the retention of a cadre of high quality nurse leaders in today's chaotic health care setting. The purpose of this study was to examine the relationship between structural empowerment and perceived organizational support and the effect of these factors on the role satisfaction of middle level nurse managers. A secondary analysis was conducted as part of a larger study of 126 middle level nurse managers working in Canadian acute care hospitals, randomly selected from the Ontario provincial registry. Eighty-four nurse managers responded to a questionnaire mailed to their home addresses. Structural empowerment was positively associated with middle level nurse managers' perceived organizational support. The combination of empowerment and perceptions of organizational support were significant predictors of middle level nurse managers' role satisfaction. The findings support R.M. Kanter's (1977, 1993; Men and Women of the Corporation. Basic Books, New York) contention that empowering work conditions have an impact on employees' feelings of support and sense of accomplishment at work. Positive perceptions of organizational support may play an important role in retaining current middle managers, and possibly attracting future leaders to management positions.

Exposure to Unsolvable Anagrams Impairs Performance on the Iowa Gambling Task

PubMed Central

Starcke, Katrin; Agorku, Janet D.; Brand, Matthias

2017-01-01

Recent research indicates that external manipulations, such as stress or mood induction, can affect decision-making abilities. In the current study, we investigated whether the exposure to an unsolvable task affected subsequent performance on the Iowa Gambling Task. Participants were randomly assigned to a condition in which they were exposed to unsolvable anagrams (n = 20), or a condition in which they worked on solvable anagrams (n = 22). Afterwards, all participants played the Iowa Gambling Task, a prominent task that measures decision making under uncertain conditions with no explicit rules for gains and losses. In this task, it is essential to process feedback from previous decisions. The results demonstrated that participants who worked on unsolvable anagrams made more disadvantageous decisions on the Iowa Gambling Task than the other participants. In addition, a significant gender effect was observed: Males who worked on unsolvable anagrams made a more disadvantageous decisions than the other male participants. Females who worked on unsolvable anagrams also made more disadvantageous decision than the other female participants, but differences were small and not significant. We conclude that the exposure to unsolvable anagrams induced the experience of uncontrollability which can elicit stress and learned helplessness. Stress and learned helplessness might have reduced the ability to learn from the given feedback, particularly in male participants. We assume that in real life, uncontrollable challenges that last longer than a single experimental manipulation can affect decision making severely, at least in males. PMID:28642693

Trapped particles at a magnetic discontinuity

NASA Technical Reports Server (NTRS)

Stern, D. P.

1972-01-01

At a tangential discontinuity between two constant magnetic fields a layer of trapped particles can exist, this work examines the conditions under which the current carried by such particles tends to maintain the discontinuity. Three cases are examined. If the discontinuity separates aligned vacuum fields, the only requirement is that they be antiparallel. With arbitrary relative orientations, the field must have equal intensities on both sides. Finally, with a guiding center plasma on both sides, the condition reduces to a relation which is also derivable from hydromagnetic theory. Arguments are presented for the occurrence of such trapped modes in the magnetopause and for the non-existence of specular particle reflection.

Impact of structural and psychological empowerment on job strain in nursing work settings: expanding Kanter's model.

PubMed

Laschinger, H K; Finegan, J; Shamian, J; Wilk, P

2001-05-01

In this study, we tested an expanded model of Kanter's structural empowerment, which specified the relationships among structural and psychological empowerment, job strain, and work satisfaction. Strategies proposed in Kanter's empowerment theory have the potential to reduce job strain and improve employee work satisfaction and performance in current restructured healthcare settings. The addition to the model of psychological empowerment as an outcome of structural empowerment provides an understanding of the intervening mechanisms between structural work conditions and important organizational outcomes. A predictive, nonexperimental design was used to test the model in a random sample of 404 Canadian staff nurses. The Conditions of Work Effectiveness Questionnaire, the Psychological Empowerment Questionnaire, the Job Content Questionnaire, and the Global Satisfaction Scale were used to measure the major study variables. Structural equation modelling analyses revealed a good fit of the hypothesized model to the data based on various fit indices (chi 2 = 1140, df = 545, chi 2/df ratio = 2.09, CFI = 0.986, RMSEA = 0.050). The amount of variance accounted for in the model was 58%. Staff nurses felt that structural empowerment in their workplace resulted in higher levels of psychological empowerment. These heightened feelings of psychological empowerment in turn strongly influenced job strain and work satisfaction. However, job strain did not have a direct effect on work satisfaction. These results provide initial support for an expanded model of organizational empowerment and offer a broader understanding of the empowerment process.

The Effect of Noise on the Relationship Between Auditory Working Memory and Comprehension in School-Age Children.

PubMed

Sullivan, Jessica R; Osman, Homira; Schafer, Erin C

2015-06-01

The objectives of the current study were to examine the effect of noise (-5 dB SNR) on auditory comprehension and to examine its relationship with working memory. It was hypothesized that noise has a negative impact on information processing, auditory working memory, and comprehension. Children with normal hearing between the ages of 8 and 10 years were administered working memory and comprehension tasks in quiet and noise. The comprehension measure comprised 5 domains: main idea, details, reasoning, vocabulary, and understanding messages. Performance on auditory working memory and comprehension tasks were significantly poorer in noise than in quiet. The reasoning, details, understanding, and vocabulary subtests were particularly affected in noise (p < .05). The relationship between auditory working memory and comprehension was stronger in noise than in quiet, suggesting an increased contribution of working memory. These data suggest that school-age children's auditory working memory and comprehension are negatively affected by noise. Performance on comprehension tasks in noise is strongly related to demands placed on working memory, supporting the theory that degrading listening conditions draws resources away from the primary task.

Pharmacology, physiology and performance: occupational drug use and HIV risk among female entertainment and sex workers in Cambodia.

PubMed

Dixon, Thomas Crewe; Ngak, Song; Stein, Ellen; Carrico, Adam; Page, Kimberly; Maher, Lisa

2015-10-16

In Cambodia, HIV prevalence among female entertainment and sex workers (FESW) is up to twenty times higher than in the general population. Use of amphetamine-type stimulants (ATS) has been associated with increased risk of HIV and other sexually transmitted infections in key populations, including FESW. While one in four Cambodian FESW report recent ATS use, little attention has been paid to how the occupational contexts of sex work shape patterns of use. Currently, no HIV prevention interventions target ATS use in this population. We conducted in-depth interviews with FESW (n = 30) with the goal of exploring experiences and motivations for ATS use and informing the development of a conditional cash transfer (CCT) intervention designed to reduce ATS use and HIV risk. Interviews were conducted and transcribed in Khmer and translated into English. Interview narratives were read and re-read and emerging themes reviewed and refined to develop an initial coding scheme. Data were formally coded using both open and axial coding to clarify and consolidate initial themes. The most common driver of ATS use among FESW was increased functionality. ATS was seen as a performance enhancer, acting as an appetite suppressant and enabling women to meet the physiological demands of sex work, including long working hours, multiple clients and extended sexual transactions. While our results are consistent with studies linking ATS use to heightened sexual risk, via unprotected and/or prolonged sex, for women in the current study, the negative consequences of ATS use were outweighed by perceived functional benefits. FESW in Cambodia harness the pharmacological properties of ATS to meet the physiological demands of sex work in a context of limited economic opportunities. There is an urgent need to both provide Cambodian women with options for income generation that do not risk their health and to better regulate the conditions of sex work to provide safer working environments. Structural and economic interventions, including CCT programmes, combined with awareness and enforcement of sex workers' rights, are also necessary to facilitate harm reduction and occupational health and work safety within the Cambodian sex and entertainment industry.

Continuing professional development: issues raised by nurses and allied health professionals working in musculoskeletal settings.

PubMed

Haywood, Hannah; Pain, Helen; Ryan, Sarah; Adams, Jo

2013-09-01

Nurses and allied health professionals (AHPs) are required to evidence their engagement in continuing professional development (CPD) in order to retain their professional registration. Many challenges to CPD are reported, but little literature has explored pertinent CPD issues for clinicians with specialist roles or working in specialist services. No literature to date has explored the perceptions of CPD held by patients who receive these specialist services. Three focus groups and two conference calls were conducted with nurses, physiotherapists, podiatrists and occupational therapists who work in musculoskeletal (MSK) services; managers of these services; and people who use MSK services. These focus groups aimed: to explore the CPD needs and issues for this group of clinicians; to explore the perceptions of CPD held by people who have MSK conditions; and to compare the above with current literature to discern any factors specific to MSK settings. The focus groups and conference calls were audio-recorded. The recordings were coded by the researchers using a priori and inductive coding. The main issues discussed were: funding and time for CPD, providing examples of ways to provide CPD in spite of the challenges faced; that CPD needs changed with level of experience; initiatives by clinical specialists to reduce professional isolation; and future trends in CPD, including concerns about succession planning. The views of people with MSK conditions demonstrated an emphasis on communication skills that was seldom raised by managers and clinicians. Sufficient time, funding and provision of study leave were key to facilitating CPD activity for nurses and AHPs working in MSK services. People with MSK conditions particularly valued health professionals who combined good listening and communication skills with an attempt to understand what it was like to live with their condition. Copyright © 2012 John Wiley & Sons, Ltd.

Integrated modeling of second phase precipitation in cold-worked 316 stainless steels under irradiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mamivand, Mahmood; Yang, Ying; Busby, Jeremy T.

The current work combines the Cluster Dynamics (CD) technique and CALPHAD-based precipitation modeling to address the second phase precipitation in cold-worked (CW) 316 stainless steels (SS) under irradiation at 300–400 °C. CD provides the radiation enhanced diffusion and dislocation evolution as inputs for the precipitation model. The CALPHAD-based precipitation model treats the nucleation, growth and coarsening of precipitation processes based on classical nucleation theory and evolution equations, and simulates the composition, size and size distribution of precipitate phases. We benchmark the model against available experimental data at fast reactor conditions (9.4 × 10 –7 dpa/s and 390 °C) and thenmore » use the model to predict the phase instability of CW 316 SS under light water reactor (LWR) extended life conditions (7 × 10 –8 dpa/s and 275 °C). The model accurately predicts the γ' (Ni 3Si) precipitation evolution under fast reactor conditions and that the formation of this phase is dominated by radiation enhanced segregation. The model also predicts a carbide volume fraction that agrees well with available experimental data from a PWR reactor but is much higher than the volume fraction observed in fast reactors. We propose that radiation enhanced dissolution and/or carbon depletion at sinks that occurs at high flux could be the main sources of this inconsistency. The integrated model predicts ~1.2% volume fraction for carbide and ~3.0% volume fraction for γ' for typical CW 316 SS (with 0.054 wt% carbon) under LWR extended life conditions. Finally, this work provides valuable insights into the magnitudes and mechanisms of precipitation in irradiated CW 316 SS for nuclear applications.« less

Integrated modeling of second phase precipitation in cold-worked 316 stainless steels under irradiation

DOE PAGES

Mamivand, Mahmood; Yang, Ying; Busby, Jeremy T.; ...

2017-03-11

The current work combines the Cluster Dynamics (CD) technique and CALPHAD-based precipitation modeling to address the second phase precipitation in cold-worked (CW) 316 stainless steels (SS) under irradiation at 300–400 °C. CD provides the radiation enhanced diffusion and dislocation evolution as inputs for the precipitation model. The CALPHAD-based precipitation model treats the nucleation, growth and coarsening of precipitation processes based on classical nucleation theory and evolution equations, and simulates the composition, size and size distribution of precipitate phases. We benchmark the model against available experimental data at fast reactor conditions (9.4 × 10 –7 dpa/s and 390 °C) and thenmore » use the model to predict the phase instability of CW 316 SS under light water reactor (LWR) extended life conditions (7 × 10 –8 dpa/s and 275 °C). The model accurately predicts the γ' (Ni 3Si) precipitation evolution under fast reactor conditions and that the formation of this phase is dominated by radiation enhanced segregation. The model also predicts a carbide volume fraction that agrees well with available experimental data from a PWR reactor but is much higher than the volume fraction observed in fast reactors. We propose that radiation enhanced dissolution and/or carbon depletion at sinks that occurs at high flux could be the main sources of this inconsistency. The integrated model predicts ~1.2% volume fraction for carbide and ~3.0% volume fraction for γ' for typical CW 316 SS (with 0.054 wt% carbon) under LWR extended life conditions. Finally, this work provides valuable insights into the magnitudes and mechanisms of precipitation in irradiated CW 316 SS for nuclear applications.« less

New innovations for contrast enhancement in electron microscopy

NASA Astrophysics Data System (ADS)

Mohan, A.

In this study two techniques for producing and improving contrast in Electron Microscopy are discussed. The first technique deals with the production of secondary contrast in a Variable Pressure SEM under poor vacuum conditions using the specimen current signal. A review of the prior work in this field shows that the presence of the gas ions in the microscope column results in the amplification of the specimen current signal which is enriched in secondary content. The focus of this study is to establish practical conditions for imaging samples in the microscope using specimen current with gas amplification. This is done by understanding the different variables in the microscope which affect the image formation process and then finding out optimum conditions for obtaining the best possible image, i.e., the image most enhanced in secondary contrast. A few 'real life' samples analyzed using this technique show that the gas amplified specimen current images contain secondary information and, in some cases, provide clear advantages to imaging with conventional secondary and backscattered detectors. The second technique dealing with the production of phase contrast in the TEM for extremely thin, electron transparent samples, is analyzed. A review of the literature regarding prior work in the field shows that, while the theoretical aspects of production of phase contrast in the TEM using a phase plate are well understood, there have been problems in practically implementing this in the microscope. One major assumption with most of the studies is that a fiber, partially coated with gold, results in the formation of point charges which is an essential requirement for symmetrically shifting the phase of the electron beam. The focus of this portion of the dissertation is to image the type of fields associated with such a phase plate using the technique of electron holography. It is found that there are two types of fields associated with a phase plate of this sort. One is a cylindrical field which extends along the length of the fiber while the other is a localized spherically symmetric field. A series of simulations show that the spherical field can produce phase contrast in the TEM and also improve the contrast transfer properties of the microscope.

Determinants of Problem Drinking and Depression among Latino Day Laborers

PubMed Central

Bacio, Guadalupe A.; Moore, Alison A.; Karno, Mitchell P.; Ray, Lara

2014-01-01

Little is known about alcohol misuse and depression among Latino day laborers despite the fact that they encounter multiple stressors (e.g. job instability, unsafe work environments). A structural equation model tested the relationships among laborer stress, social support, health status, current alcohol misuse, and depression. A sample of 89 male, urban Latino day laborers completed measures assessing these constructs in 2011. Stress was negatively related to physical health status, which was associated with depression. Findings suggest that stressors specific to being a day laborer resulting from their work and living conditions generate and maintain health disparities in this vulnerable population. PMID:24779503

Working conditions and health among employees at information technology--enabled services: a review of current evidence.

PubMed

Kesavachandran, C; Rastogi, S K; Das, Mohan; Khan, Asif M

2006-07-01

Workers in information technology (IT)-enabled services like business process outsourcing and call centers working with visual display units are reported to have various health and psycho-social disorders. Evidence from previously published studies in peer- reviewed journals and internet sources were examined to explore health disorders and psycho-social problems among personnel employed in IT-based services, for a systematic review on the topic. In addition, authors executed a questionnaire- based pilot study. The available literature and the pilot study, both suggest health disorders and psychosocial problems among workers of business process outsourcing. The details are discussed in the review.

Home monitoring of patients with Parkinson's disease via wearable technology and a web-based application.

PubMed

Patel, Shyamal; Chen, Bor-Rong; Buckley, Thomas; Rednic, Ramona; McClure, Doug; Tarsy, Daniel; Shih, Ludy; Dy, Jennifer; Welsh, Matt; Bonato, Paolo

2010-01-01

Objective long-term health monitoring can improve the clinical management of several medical conditions ranging from cardiopulmonary diseases to motor disorders. In this paper, we present our work toward the development of a home-monitoring system. The system is currently used to monitor patients with Parkinson's disease who experience severe motor fluctuations. Monitoring is achieved using wireless wearable sensors whose data are relayed to a remote clinical site via a web-based application. The work herein presented shows that wearable sensors combined with a web-based application provide reliable quantitative information that can be used for clinical decision making.

Oxygen and iron production by electrolytic smelting of lunar soil

NASA Technical Reports Server (NTRS)

Haskin, Larry A.

1989-01-01

Previous work has shown that Fe(sup 0) and O2 can be derived by electrolysis from silicate smelt of a composition typical of lunar soils (Lindstrom and Haskin 1979). In the present study, the goal is to refine further the conditions necessary to optimize production and to determine efficiencies of production (how much product is derived for a given current) and purity of products. These depend on several factors, including potential imposed between electrodes, configuration and surface area of the electrodes, composition of the electrolyzed silicate melt, and oxygen fugacity. Experiments were designed to measure the dependence on these variables of three parameters that must be known before production by electrolysis can be optimized. These parameters are: Limiting Current; Actual Current; and Efficiencies of Production.

Conditioning of BPM pickup signals for operations of the Duke storage ring with a wide range of single-bunch current

NASA Astrophysics Data System (ADS)

Xu, Wei; Li, Jing-Yi; Huang, Sen-Lin; Z. Wu, W.; Hao, H.; P., Wang; K. Wu, Y.

2014-10-01

The Duke storage ring is a dedicated driver for the storage ring based oscillator free-electron lasers (FELs), and the High Intensity Gamma-ray Source (HIGS). It is operated with a beam current ranging from about 1 mA to 100 mA per bunch for various operations and accelerator physics studies. High performance operations of the FEL and γ-ray source require a stable electron beam orbit, which has been realized by the global orbit feedback system. As a critical part of the orbit feedback system, the electron beam position monitors (BPMs) are required to be able to precisely measure the electron beam orbit in a wide range of the single-bunch current. However, the high peak voltage of the BPM pickups associated with high single-bunch current degrades the performance of the BPM electronics, and can potentially damage the BPM electronics. A signal conditioning method using low pass filters is developed to reduce the peak voltage to protect the BPM electronics, and to make the BPMs capable of working with a wide range of single-bunch current. Simulations and electron beam based tests are performed. The results show that the Duke storage ring BPM system is capable of providing precise orbit measurements to ensure highly stable FEL and HIGS operations.

Depression and Behavioral Problems Among Adolescent Girls and Young Women Employees of the Textile Industry in India.

PubMed

Gnanaselvam, Nancy Angeline; Joseph, Bobby

2018-01-01

Stress and depression are common in textile industry employees due to inadequate working conditions and challenging socioeconomic conditions. The objective of the study was to assess depression and mental health among adolescent and young females currently employed in a textile factory located in Tamil Nadu compared with past employees and women who have never been employed. This cross-sectional study included a total of 107 participants in each study group who were interviewed. The Patient Health Questionnaire-9 and Strengths and Difficulties Questionnaire were administered to screen participants for depression and mental health. More current employees (16.82%) and past employees (15.88%) suffered from depression severe enough to require treatment compared with never employed girls and young women (2.8%). Of the study participants, 59.8% of current employees, 63.6% of past employees, and 32.7% of never employed women had mental health or behavior problems. In the regression model, history of abuse was significantly associated with depression. Participants who were current employees and reported family debt and a history of abuse were significantly more likely to have mental health or behavior problems. Mental health issues such as depression and behavior problems were more likely among adolescent girls currently employed in textile industries. Further studies into the causes of this phenomenon are needed.

Effects of Psychological and Social Factors in Shiftwork on Symptoms of Anxiety and Depression in Nurses: A 1-Year Follow-Up.

PubMed

Berthelsen, Mona; Pallesen, Ståle; Magerøy, Nils; Tyssen, Reidar; Bjorvatn, Bjørn; Moen, Bente Elisabeth; Knardahl, Stein

2015-10-01

The aim of the current study was to elucidate prospective effects of both shift schedules and work environment on mental distress. A total of 2059 nurses participated at baseline (38.1%), and 1582 nurses completed wave 2 of the survey (76.8%). Psychosocial work factors were measured by the General Nordic Questionnaire for Psychological and Social factors at work and the Swedish Demand-Control-Support Questionnaire. Mental distress was measured by Hospital Anxiety and Depression Scale. Shiftwork was not associated with "caseness" anxiety or depression. Effects of shiftwork on mental distress were not moderated by psychosocial work factors. Mental distress predicted role clarity, role conflict, fair leadership, and social support. Job demands predicted symptoms of depression. Whether psychosocial working conditions buffer mental health effects of shiftwork remains undecided. Prospective studies with multiple measurement points are needed to elucidate potential mutual relationships between work factors and mental distress.

[Alcohol and work: the role of the company physician in the occupational health and safety management systems].

PubMed

Patussi, V; Muran, A

2010-01-01

The organization of safety in the working places and the increasing attention to behaviours and life styles of workers that may lead to increasing occupational risks are the pick innovative aspects of the recent changes in our country's legislation about occupational safety. In this organization, the role of the company physician is becoming more and more important and his work of evaluation beginning with the knowledge both of the working places and of the workers's lifestyles, is irreplaceable. His role in organizing the managing standards of occupational safety and health cannot be limited to health supervision but must be an essential element in risk assessment in the prevision of workplaces and of safe working conditions, in workers training and information, in organizing the control system of each business. The present paper examines--referring to the current regulation--the duties and functions of a company physician when facing the problems concerning the working risks tied to alcohol assumption.

Investigations of current limiting properties of the MgB2 wires subjected to pulse overcurrents in the benchtop tester

NASA Astrophysics Data System (ADS)

Ye, Lin; Majoros, M.; Campbell, A. M.; Coombs, T.; Harrison, S.; Sargent, P.; Haslett, M.; Husband, M.

2007-04-01

A laboratory scale desktop test system including a cryogenic system, an AC pulse generation system and a real time data acquisition program in LabView/DAQmx, has been developed to evaluate the quench properties of MgB2 wires as an element in a superconducting fault current limiter under pulse overcurrents at 25 K in self-field conditions. The MgB2 samples started from a superconducting state and demonstrated good current limiting properties characterized by a fast transition to the normal state during the first half of the cycle and a continuously limiting effect in the subsequent cycles without burnouts. The experimental and numerical simulation results on the quench behaviour indicate the feasibility of using MgB2 for future superconducting fault current limiter (SFCL) applications. This work is supported by Rolls-Royce Plc and the UK Department of Trade & Industry (DTI).

Thermal Modelling Analysis of Spiral Wound Supercapacitor under Constant-Current Cycling

PubMed Central

Wang, Kai; Li, Liwei; Yin, Huaixian; Zhang, Tiezhu; Wan, Wubo

2015-01-01

A three-dimensional modelling approach is used to study the effects of operating and ambient conditions on the thermal behaviour of the spiral wound supercapacitor. The transient temperature distribution during cycling is obtained by using the finite element method with an implicit predictor-multicorrector algorithm. At the constant current of 2A, the results show that the maximum temperature appears in core area. After 5 cycles, the maximum temperature is 34.5°C, while in steady state, it’s up to 42.5°C. This paper further studies the relationship between the maximum temperature and charge-discharge current. The maximum temperature will be more than 60°C after 5 cycles at the current of 4A, and cooling measurements should be taken at that time. It can provide thoughts on inner temperature field distribution and structure design of the spiral wound supercapacitor in working process. PMID:26444687

Mutagenic and genotoxic potential of direct electric current in Escherichia coli and Salmonella thyphimurium strains.

PubMed

Gomes, Marina das Neves; Cardoso, Janine Simas; Leitão, Alvaro Costa; Quaresma, Carla Holandino

2016-05-01

Direct electric current has several therapeutic uses such as antibacterial and antiprotozoal action, tissues scarring and regeneration, as well as tumor treatment. This method has shown promising results in vivo and in vitro, with significant efficacy and almost no side effects. Considering lack of studies regarding direct electric current mutagenic and/or genotoxic effects, the present work evaluated both aspects by using five different bacterial experimental assays: survival of repair-deficient mutants, Salmonella-histidine reversion mutagenesis (Ames test), forward mutations to rifampicin resistance, phage reactivation, and lysogenic induction. In these experimental conditions, cells were submitted to an approach that allows evaluation of anodic, cathodic, and electro-ionic effects generated by 2 mA of direct electric current, with doses ranging from 0.36 to 3.60 Coulombs. Our results showed these doses did not induce mutagenic or genotoxic effects. © 2016 Wiley Periodicals, Inc.

Reduced intensity conditioning allogeneic hematopoietic cell transplantation for adult acute myeloid leukemia in complete remission - a review from the Acute Leukemia Working Party of the EBMT

PubMed Central

Sengsayadeth, Salyka; Savani, Bipin N.; Blaise, Didier; Malard, Florent; Nagler, Arnon; Mohty, Mohamad

2015-01-01

Acute myeloid leukemia is the most common indication for an allogeneic hematopoietic cell transplant. The introduction of reduced intensity conditioning has expanded the recipient pool for transplantation, which has importantly made transplant an option for the more commonly affected older age groups. Reduced intensity conditioning allogeneic transplantation is currently the standard of care for patients with intermediate or high-risk acute myeloid leukemia and is now most often employed in older patients and those with medical comorbidities. Despite being curative for a significant proportion of patients, post-transplant relapse remains a challenge in the reduced intensity conditioning setting. Herein we discuss the studies that demonstrate the feasibility of reduced intensity conditioning allogeneic transplants, compare the outcomes of reduced intensity conditioning versus chemotherapy and conventional myeloablative conditioning regimens, describe the optimal donor and stem cell source, and consider the impact of post-remission consolidation, comorbidities, center experience, and more intensive (reduced toxicity conditioning) regimens on outcomes. Additionally, we discuss the need for further prospective studies to optimize transplant outcomes. PMID:26130513

Approaches to long-term conditions management and care for older people: similarities or differences?

PubMed

Tullett, Michael; Neno, Rebecca

2008-03-01

In the past few years, there has been an increased emphasis both on the care for older people and the management of long-term conditions within the United Kingdom. Currently, the Department of Health and the Scottish Executive identify and manage these two areas as separate entities. The aim of this article is to examine the current approaches to both of these areas of care and identify commonalities and articulate differences. The population across the world and particularly within the United Kingdom is ageing at an unprecedented rate. The numbers suffering long-term illness conditions has also risen sharply in recent years. As such, nurses need to be engaged at a strategic level in the design of robust and appropriate services for this increasing population group. A comprehensive literature review on long-term conditions and the care of older people was undertaken in an attempt to identify commonalities and differences in strategic and organizational approaches. A policy analysis was conducted to support the paper and establish links that may inform local service development. Proposing service development based on identified needs rather than organizational boundaries after the establishment of clear links between health and social care for those with long-term conditions and the ageing population. Nurse Managers need to be aware of the similarities and differences in political and theoretical approaches to the care for older people and the management of long-term conditions. By adopting this view, creativity in the service redesign and service provision can be fostered and nurtured as well as achieving a renewed focus on partnership working across organizational boundaries. With the current renewed political focus on health and social care, there is an opportunity in the UK to redefine the structure of care. This paper proposes similarities between caring for older people and for those with long-term conditions, and it is proposed these encapsulate the wider issues that need to be debated to achieve a truly joint approach to care.

Scaling the Shear-flow Stabilized Z-pinch to Reactor Conditions

NASA Astrophysics Data System (ADS)

McLean, H. S.; Schmidt, A.; Shumlak, U.; Nelson, B. A.; Golingo, R. P.; Cleveau, E.

2015-11-01

We present a conceptual design along with scaling calculations for a pulsed fusion reactor based on the shear-flow-stabilized Z-pinch device. Experiments performed on the ZaP device, at the University of Washington, have demonstrated stable operation for durations of 20 usec at ~100kA discharge current for pinches that are ~1 cm in diameter and 100 cm long. The inverse of the pinch diameter and plasma energy density scale strongly with pinch current and calculations show that maintaining stabilization durations of ~7 usec for increased discharge current (~15x) in a shortened pinch (10 cm) results in a pinch diameter of ~200 um and plasma conditions that approach those needed to support significant fusion burn and energy gain (Ti ~ 30keV, density ~ 3e26/m3, ntau ~1.4e20 sec/m3). Compelling features of the concept include operation at modest discharge current (1.5 MA) and voltage (40kV) along with direct adoption of liquid metals for at least one electrode--technological capabilities that have been proven in existing, commercial, pulse power devices such as large ignitrons. LLNL-ABS-674920. This work performed under the auspices of the U.S. Department of Energy ARPAe ALPHA Program by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

Association Between Employee Sleep With Workplace Health and Economic Outcomes.

PubMed

Burton, Wayne N; Chen, Chin-Yu; Schultz, Alyssa B; Li, Xingquan

2017-02-01

Poor sleep can impact occupational functioning. The current study examines health risks, medical conditions, and workplace economic outcomes associated with self-reported hours of sleep among employees. Employees of a global financial services corporation were categorized on the basis of their self-reported average hours of sleep. Differences in health care costs, productivity measures, health risks, and medical conditions were analyzed by hours of sleep while controlling for confounding variables. A strong U-shaped relationship between health care costs, short-term disability, absenteeism, and presenteeism (on-the-job work loss) and the hours of sleep was found among employees. The nadir of the "U" occurs for 7 or 8 hours of sleep per night. Worksite wellness programs often address health risks and medical conditions and may benefit from incorporating sleep education.

Physical exercise improves learning in zebrafish, Danio rerio.

PubMed

Luchiari, Ana Carolina; Chacon, Diana Marques Martins

2013-11-01

Zebrafish is an ideal vertebrate model for neuroscience studies focusing on learning and memory. Although genetic manipulation of zebrafish is available, behavioral protocols are often lacking. In this study we tested whether physical activity can facilitate zebrafish's learning process in an associative conditioning task. Learning was inferred by the approach of the feeding area just after the conditioned stimulus (light). Unexercised zebrafish showed conditioning response from the 5th testing day while fish previously submitted to swim against the water current showed learning by the 3rd day of testing. It seems that physical activity may accelerate associative learning response in zebrafish, indicating the benefits of exercise for cognitive processes. We suggest that this preliminary work could be useful for high throughput screening. Copyright © 2013 Elsevier B.V. All rights reserved.

Optimal chemotactic responses in stochastic environments

PubMed Central

Godány, Martin

2017-01-01

Although the “adaptive” strategy used by Escherichia coli has dominated our understanding of bacterial chemotaxis, the environmental conditions under which this strategy emerged is still poorly understood. In this work, we study the performance of various chemotactic strategies under a range of stochastic time- and space-varying attractant distributions in silico. We describe a novel “speculator” response in which the bacterium compare the current attractant concentration to the long-term average; if it is higher then they tumble persistently, while if it is lower than the average, bacteria swim away in search of more favorable conditions. We demonstrate how this response explains the experimental behavior of aerobically-grown Rhodobacter sphaeroides and that under spatially complex but slowly-changing nutrient conditions the speculator response is as effective as the adaptive strategy of E. coli. PMID:28644830

Juggling work and motherhood: the impact of employment and maternity leave on breastfeeding duration: a survival analysis on Growing Up in Scotland data.

PubMed

Skafida, Valeria

2012-02-01

In 2005, Scotland became the first nation to make breastfeeding in public a legal right, but current breastfeeding targets and maternity leave allowance do not acknowledge the conflicting demands women face when juggling employment and motherhood. This paper explores how employment and maternity leave relate to breastfeeding duration among mothers in Scotland. The Growing Up in Scotland national longitudinal cohort study of 5,217 babies born in 2004-2005 was used. Multivariate proportional hazards regression models were specified using one cross-sectional wave of data to predict breastfeeding duration. Mothers working as employees, full-time (Hazard Ratio 1.6) or part-time (HR1.3), had a higher risk of earlier breastfeeding cessation than non-working mothers. However, self-employed mothers did not differ significantly from non-working mothers in their breastfeeding patterns. Mothers who took longer maternity leave breastfed for longer. The relationships between employment, maternity leave and breastfeeding duration were significant when controlling for known predictors of breastfeeding. Younger mothers, those with less formal education, single mothers, those of white ethnic background, and first-time mothers were more likely to stop breastfeeding sooner, as has been noted in previous research. Employment and early return to work are both factors associated with a shorter duration of breastfeeding. More flexible working conditions and more generous employment leave could help to prolong breastfeeding among working mothers. Current health and employment policy in Scotland and the UK could be better coordinated so that working mothers have the adequate support to meet the conflicting demands of employment and motherhood.

Systematic parameter estimation and sensitivity analysis using a multidimensional PEMFC model coupled with DAKOTA.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Chao Yang; Luo, Gang; Jiang, Fangming

2010-05-01

Current computational models for proton exchange membrane fuel cells (PEMFCs) include a large number of parameters such as boundary conditions, material properties, and numerous parameters used in sub-models for membrane transport, two-phase flow and electrochemistry. In order to successfully use a computational PEMFC model in design and optimization, it is important to identify critical parameters under a wide variety of operating conditions, such as relative humidity, current load, temperature, etc. Moreover, when experimental data is available in the form of polarization curves or local distribution of current and reactant/product species (e.g., O2, H2O concentrations), critical parameters can be estimated inmore » order to enable the model to better fit the data. Sensitivity analysis and parameter estimation are typically performed using manual adjustment of parameters, which is also common in parameter studies. We present work to demonstrate a systematic approach based on using a widely available toolkit developed at Sandia called DAKOTA that supports many kinds of design studies, such as sensitivity analysis as well as optimization and uncertainty quantification. In the present work, we couple a multidimensional PEMFC model (which is being developed, tested and later validated in a joint effort by a team from Penn State Univ. and Sandia National Laboratories) with DAKOTA through the mapping of model parameters to system responses. Using this interface, we demonstrate the efficiency of performing simple parameter studies as well as identifying critical parameters using sensitivity analysis. Finally, we show examples of optimization and parameter estimation using the automated capability in DAKOTA.« less

Unilateral prefrontal direct current stimulation effects are modulated by working memory load and gender.

PubMed

Meiron, Oded; Lavidor, Michal

2013-05-01

Recent studies revealed that anodal transcranial direct current stimulation (tDCS) to the left dorsolateral prefrontal cortex (DLPFC) may improve verbal working memory (WM) performance in humans. In the present study, we evaluated executive attention, which is the core of WM capacity, considered to be significantly involved in tasks that require active maintenance of memory representations in interference-rich conditions, and is highly dependent on DLPFC function. We investigated verbal WM accuracy using a WM task that is highly sensitive to executive attention function. We were interested in how verbal WM accuracy may be affected by WM load, unilateral DLPFC stimulation, and gender, as previous studies showed gender-dependent brain activation during verbal WM tasks. We utilized a modified verbal n-Back task hypothesized to increase demands on executive attention. We examined "online" WM performance while participants received transcranial direct current stimulation (tDCS), and implicit learning performance in a post-stimulation WM task. Significant lateralized "online" stimulation effects were found only in the highest WM load condition revealing that males benefit from left DLPFC stimulation, while females benefit from right DLPFC stimulation. High WM load performance in the left DLPFC stimulation was significantly related to post-stimulation recall performance. Our findings support the idea that lateralized stimulation effects in high verbal WM load may be gender-dependent. Further, our post-stimulation results support the idea that increased left hemisphere activity may be important for encoding verbal information into episodic memory as well as for facilitating retrieval of context-specific targets from semantic memory. Copyright © 2013 Elsevier Inc. All rights reserved.

Experimental study on magnetically insulated transmission line electrode surface evolution process under MA/cm current density

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, PengFei; Qiu, Aici; State Key Laboratory of Intense Pulse Radiation of Simulation and Effect, Northwest Institute of Nuclear Technology, Xi'an 710024

The design of high-current density magnetically insulated transmission line (MITL) is a difficult problem of current large-scale Z-pinch device. In particular, a thorough understanding of the MITL electrode surface evolution process under high current density is lacking. On the “QiangGuang-I” accelerator, the load area possesses a low inductance short-circuit structure with a diameter of 2.85 mm at the cathode, and three reflux columns with a diameter of 3 mm and uniformly distributed circumference at the anode. The length of the high density MITL area is 20 mm. A laser interferometer is used to assess and analyze the state of the MITL cathode andmore » anode gap, and their evolution process under high current density. Experimental results indicate that evident current loss is not observed in the current density area at pulse leading edge, and peak when the surface current density reaches MA/cm. Analysis on electrode surface working conditions indicates that when the current leading edge is at 71.5% of the peak, the total evaporation of MITL cathode structure can be realized by energy deposition caused by ohmic heating. The electrode state changes, and diffusion conditions are reflected in the laser interferometer image. The MITL cathode area mainly exists in metal vapor form. The metal vapor density in the cathode central region is higher than the upper limit of laser penetration density (∼4 × 10{sup 21}/cm{sup 3}), with an expansion velocity of ∼0.96 km/s. The metal vapor density in the electrode outer area may lead to evident distortion of fringes, and its expansion velocity is faster than that in the center area (1.53 km/s).« less

Top-down influences on ambiguous perception: the role of stable and transient states of the observer

PubMed Central

Scocchia, Lisa; Valsecchi, Matteo; Triesch, Jochen

2014-01-01

The world as it appears to the viewer is the result of a complex process of inference performed by the brain. The validity of this apparently counter-intuitive assertion becomes evident whenever we face noisy, feeble or ambiguous visual stimulation: in these conditions, the state of the observer may play a decisive role in determining what is currently perceived. On this background, ambiguous perception and its amenability to top-down influences can be employed as an empirical paradigm to explore the principles of perception. Here we offer an overview of both classical and recent contributions on how stable and transient states of the observer can impact ambiguous perception. As to the influence of the stable states of the observer, we show that what is currently perceived can be influenced (1) by cognitive and affective aspects, such as meaning, prior knowledge, motivation, and emotional content and (2) by individual differences, such as gender, handedness, genetic inheritance, clinical conditions, and personality traits and by (3) learning and conditioning. As to the impact of transient states of the observer, we outline the effects of (4) attention and (5) voluntary control, which have attracted much empirical work along the history of ambiguous perception. In the huge literature on the topic we trace a difference between the observer's ability to control dominance (i.e., the maintenance of a specific percept in visual awareness) and reversal rate (i.e., the switching between two alternative percepts). Other transient states of the observer that have more recently drawn researchers' attention regard (6) the effects of imagery and visual working memory. (7) Furthermore, we describe the transient effects of prior history of perceptual dominance. (8) Finally, we address the currently available computational models of ambiguous perception and how they can take into account the crucial share played by the state of the observer in perceiving ambiguous displays. PMID:25538601