WorldWideScience

Sample records for model occupational stressors

  1. Occupational stressors in nursing

    Directory of Open Access Journals (Sweden)

    N. Nikpeyma

    2009-04-01

    Full Text Available Background and aimsNursing provides a wide range of potential workplace stressors as it is  a profession that requires a high level of skill, teamworking in a variety of situations and provision  of 24-hour delivery of care .Occupational stress is a major factor of Staff sickness an  absenteeism.This study investigates the main occupational stressors in nursing profession in the  hope of identification and reducing it.MethodsIn this study a questionnaire consisting of three parts:demoghraphic data,the nurses  background and questions about occupational stress from Revised index fulfilled by 140 nurses.ResultsLack of reward for work well done(48/6%, Heavy workload(46/4% ,lack of Participation in decisions (39/3% , poor Control of work place(38/4%and lack of job  development (36/4% have been the main sources of Occupational stress for nurses.chronic  diseases, Night Shift working and working hours were positively associated with occupstional  stress.Conclusion Analysis indicated that effects of work factors on occupational stress are more than demoghraphic data. The findings of this study can assist health service organisations to provide an attractive working climate in order to decrease side effects and consequences of occupational stress. Furthermore, understanding this situation can help to develop coping strategies in order to reduce work-related stress.

  2. Hotel housekeeping occupational stressors in Norway

    OpenAIRE

    Yap, Matthew H. T.

    2011-01-01

    Stress is evident in the Norwegian hotel industry and requires urgent attention as portrayed in Annbjørg’s housekeeping managerial occupation. Annbjørg’s occupational stressors derived from weak control of and support for demanding jobs in the housekeeping department and possibly under-reward in comparison to her tireless efforts. Hence, this case study provides a platform for educators, trainers, managers, students and learners to critically examine, discuss and argue managerial occupational...

  3. [Appraisal of occupational stressor in petrochemical industry workers].

    Science.gov (United States)

    Tang, Xiao-ping; Tian, Hong-er; Huang, Tong; Li, Zhi-yuan; Hu, Ke-ming; Ge, Xi-yong; Jin, Lei; Gao, Qi; Zhang, Jing-jing; Wang, Yu; Liu, Wen-he

    2009-12-01

    To discuss the origin of occupational stress among petrochemical industry workers and to access the main occupational stressors that impact job satisfaction and mental health of petrochemical industry workers. A survey on occupational stressor was carried out by Occupational Stress Indicator (OSI) in 532 petrochemical industry workers (345 chemical and 187 logistic workers). The environment in workplace of chemical group was worse than that of contrast. The chemical workers had less control over job and they experienced more hazards, monotonous as well as role stressors than the logistic group. The scores of job satisfaction and mental health of chemical group (36.867 +/- 0.656, 43.734 +/- 0.542, respectively) were higher than that of contrast (40.321 +/- 0.901, 46.714 +/- 0.745, respectively) (P job satisfaction and mental health with different levels.

  4. Occupational Stressors and Job Satisfaction of Pennsylvania School District Superintendents

    Science.gov (United States)

    Kane, Kevin T.

    2017-01-01

    Today's superintendents face increasingly non-routine and complex problems that are educational, managerial, and political in nature. This study investigated occupational stressors and job satisfaction of school superintendents in Pennsylvania. This was accomplished through self-report of superintendents and through the perspective of school board…

  5. Military Occupational Stressors in Garrison, Training, and Deployed Environments

    National Research Council Canada - National Science Library

    Adler, Amy

    2004-01-01

    As part of the Walter Reed Army Institute of Research (WRAIR) program to model soldier stress, health, and performance, stressors are analyzed across a variety of environments in terms of their impact on military personnel...

  6. Job-Occupation Misfit as an Occupational Stressor

    Science.gov (United States)

    Ford, Michael T.

    2012-01-01

    Drawing from theory on met expectations, person-environment fit, and social information processing, misfit between the pressure and autonomy experienced by workers and that which would be expected given their occupational roles was examined as a predictor of job satisfaction, perceived support, and depression. Results from a nationally (U.S.)…

  7. Considering Environmental and Occupational Stressors in Cumulative Risk Assessments

    Science.gov (United States)

    While definitions vary across the global scientific community, cumulative risk assessments (CRAs) typically are described as exhibiting a population focus and analyzing the combined risks posed by multiple stressors. CRAs also may consider risk management alternatives as an anal...

  8. Occupational stressors among nurses working in urgent and emergency care units

    Directory of Open Access Journals (Sweden)

    Denyson Santana PEREIRA

    Full Text Available The study aimed to assess occupational stressors among nurses working in urgent and emergency care facilities. It is a descriptive research developed in two public hospitals of different complexity degrees, with 49 nurses. Data were collected from June to September 2011. The Bianchi's Stress Scale, which is composed of six domains: Relationship, Unit functioning, Staff management, Nursing care, Unit coordination, and Work conditions was used to assess occupational stressors based on the regular activities performed by nurses. Data were analyzed by using descriptive statistics and Mann Whitney-U test. For the nurses working in the high complexity healthcare facility - hospital A the most stressful domain was Nursing care, while for those professionals working in the medium complexity healthcare facility - hospital B, Staff management was the most stressful domain. The nurses from hospital A perceived care-related activities as more stressful, while for those in hospital B administrative activities were considered more stressful.

  9. The Heath Occupational Model.

    Science.gov (United States)

    Heath, William E.

    1990-01-01

    Career development programs must identify occupational needs of adults. A model based on Maslow's hierarchy develops occupational questions related to individual motivations (physiology, safety, love, esteem, and self-actualization). Individual needs are then compared with characteristics and benefits of proposed jobs, companies, or careers. (SK)

  10. Occupational stressors, burnout and coping strategies between hospital and community psychiatric nurses in a Dublin region.

    Science.gov (United States)

    McTiernan, K; McDonald, N

    2015-04-01

    Burnout negatively impacts the delivery of mental health services. Psychiatric nurses face stressors that are distinct from other nursing specialities. The research was conducted in Ireland and captured a relatively large sample of respondents. The results compared the stressors, coping strategies and burnout levels between hospital and community-based psychiatric nurses. Occupational stress can negatively impact on the well-being of psychiatric nurses, which in turn can lead to poor client care. There is a dearth of published research conducted in Ireland that examines stress within the discipline. A between-groups study, undertaken in February 2011, investigated stressors, burnout and coping strategies between hospital and community-based psychiatric nurses in a Dublin region. Sixty-nine participants (8 males and 61 females), aged between 18 to 60 years voluntarily completed the Mental Health Professional Stress Scale, the Maslach Burnout Inventory and the PsychNurse Methods of Coping Scale. The findings revealed that nurses were operating in a moderately stressful environment. Stressors focused on organizational issues as opposed to client issues. The main stressors identified were lack of resources, workload and organizational structures/processes. Both groups reported average levels of emotional exhaustion, low levels of depersonalization and average levels of personal accomplishment. A Mann-Whitney U-test and Independent Samples t-test found significant differences between hospital and community-based nurses regarding depersonalization and personal accomplishment, respectively. Hospital nurses reported higher depersonalization scores, and community nurses had a greater sense of personal accomplishment. The personal accomplishment scores of hospital nurses were below mental health professional norms. No significant differences emerged regarding coping strategies. Avoidant coping strategies were favoured by both groups. It is recommended that interventions

  11. Associations of Occupational Stressors, Perceived Organizational Support, and Psychological Capital with Work Engagement among Chinese Female Nurses

    Directory of Open Access Journals (Sweden)

    Xiaoxi Wang

    2017-01-01

    Full Text Available This study aimed to explore the associations of occupational stressors (extrinsic effort, reward, and overcommitment, perceived organizational support (POS, and psychological capital (PsyCap and its components (self-efficacy, hope, resilience, and optimism with work engagement and the mediating roles of PsyCap and its components among Chinese female nurses within the framework of the job demands-resources (JD-R model. A cross-sectional sample (1,330 completed the Utrecht Work Engagement Scale, Effort-Reward Imbalance Scale, Survey of POS, and PsyCap Questionnaire, and effective respondents were 1,016 (76.4%. Hierarchical regression analysis and Preacher and Hayes’ asymptotic and resampling strategies were used. Extrinsic effort was negatively associated with vigor, dedication, and absorption, while POS, PsyCap, and hope were positively associated with them. Reward and overcommitment were positively associated with dedication and absorption. Optimism was positively associated with vigor and dedication. Optimism mediated the associations of extrinsic effort, reward, and POS with vigor and dedication. PsyCap and hope mediated the associations of POS with vigor, dedication, and absorption. There is a low level of work engagement among Chinese female nurses. Extrinsic effort could reduce work engagement, while reward, overcommitment, POS, PsyCap, hope, and optimism could enhance work engagement. Hospital managers should develop the PsyCap of female nurses through controlling occupational stressors and establishing supportive organizational climate to enhance their work engagement.

  12. Associations of Occupational Stressors, Perceived Organizational Support, and Psychological Capital with Work Engagement among Chinese Female Nurses.

    Science.gov (United States)

    Wang, Xiaoxi; Liu, Li; Zou, Futing; Hao, Junhui; Wu, Hui

    2017-01-01

    This study aimed to explore the associations of occupational stressors (extrinsic effort, reward, and overcommitment), perceived organizational support (POS), and psychological capital (PsyCap) and its components (self-efficacy, hope, resilience, and optimism) with work engagement and the mediating roles of PsyCap and its components among Chinese female nurses within the framework of the job demands-resources (JD-R) model. A cross-sectional sample (1,330) completed the Utrecht Work Engagement Scale, Effort-Reward Imbalance Scale, Survey of POS, and PsyCap Questionnaire, and effective respondents were 1,016 (76.4%). Hierarchical regression analysis and Preacher and Hayes' asymptotic and resampling strategies were used. Extrinsic effort was negatively associated with vigor, dedication, and absorption, while POS, PsyCap, and hope were positively associated with them. Reward and overcommitment were positively associated with dedication and absorption. Optimism was positively associated with vigor and dedication. Optimism mediated the associations of extrinsic effort, reward, and POS with vigor and dedication. PsyCap and hope mediated the associations of POS with vigor, dedication, and absorption. There is a low level of work engagement among Chinese female nurses. Extrinsic effort could reduce work engagement, while reward, overcommitment, POS, PsyCap, hope, and optimism could enhance work engagement. Hospital managers should develop the PsyCap of female nurses through controlling occupational stressors and establishing supportive organizational climate to enhance their work engagement.

  13. Association of Emotional Labor and Occupational Stressors with Depressive Symptoms among Women Sales Workers at a Clothing Shopping Mall in the Republic of Korea: A Cross-Sectional Study

    Directory of Open Access Journals (Sweden)

    Yuh-Jin Chung

    2017-11-01

    Full Text Available In the distribution service industry, sales people often experience multiple occupational stressors such as excessive emotional labor, workplace mistreatment, and job insecurity. The present study aimed to explore the associations of these stressors with depressive symptoms among women sales workers at a clothing shopping mall in Korea. A cross sectional study was conducted on 583 women who consist of clothing sales workers and manual workers using a structured questionnaire to assess demographic factors, occupational stressors, and depressive symptoms. Multiple regression analyses were performed to explore the association of these stressors with depressive symptoms. Scores for job stress subscales such as job demand, job control, and job insecurity were higher among sales workers than among manual workers (p < 0.01. The multiple regression analysis revealed the association between occupation and depressive symptoms after controlling for age, educational level, cohabiting status, and occupational stressors (sβ = 0.08, p = 0.04. A significant interaction effect between occupation and social support was also observed in this model (sβ = −0.09, p = 0.02. The multiple regression analysis stratified by occupation showed that job demand, job insecurity, and workplace mistreatment were significantly associated with depressive symptoms in both occupations (p < 0.05, although the strength of statistical associations were slightly different. We found negative associations of social support (sβ = −0.22, p < 0.01 and emotional effort (sβ = −0.17, p < 0.01 with depressive symptoms in another multiple regression model for sales workers. Emotional dissonance (sβ = 0.23, p < 0.01 showed positive association with depressive symptoms in this model. The result of this study indicated that reducing occupational stressors would be effective for women sales workers to prevent depressive symptoms. In particular, promoting social support could be the most

  14. The impact of environmental stressors and types of work contract on occupational stress.

    Science.gov (United States)

    Corrêa, Ana Paula; Ferreira, Maria Cristina

    2011-05-01

    This study aimed to investigate the impact of seven environmental stressors (role conflict, work overload, interpersonal difficulties, work-family conflict, work instability, lack of autonomy and pressure of responsibility) and the nature of the employment contract (permanent or atypical) on three psychological reactions to occupational stress (job satisfaction, positive emotions, and negative emotions at work). 305 Brazilian workers from both sexes participated in this research, distributed between permanent and atypical workers. The results showed that the role conflict and the work overload had a negative impact on job satisfaction. The role conflict had a negative impact on the positive emotions at work, while the pressure of responsibility interfered positively in it. The work overload interfered positively in the negative emotions at work, while the pressure of responsibility interfered negatively in it. The type of contract did not affect significantly any one of the dependent variables. The implications of the results for future research are discussed.

  15. Predictors of occupational burnout among nurses: a dominance analysis of job stressors.

    Science.gov (United States)

    Sun, Ji-Wei; Bai, Hua-Yu; Li, Jia-Huan; Lin, Ping-Zhen; Zhang, Hui-Hui; Cao, Feng-Lin

    2017-12-01

    To quantitatively compare dimensions of job stressors' effects on nurses' burnout. Nurses, a key group of health service providers, often experience stressors at work. Extensive research has examined the relationship between job stressors and burnout; however, less has specifically compared the effects of job stressor domains on nurses' burnout. A quantitative cross-sectional survey examined three general hospitals in Jinan, China. Participants were 602 nurses. We compared five potential stressors' ability to predict nurses' burnout using dominance analysis and assuming that each stressor was intercorrelated. Strong positive correlations were found between all five job stressors and burnout. Interpersonal relationships and management issues most strongly predicted participants' burnout (11·3% of average variance). Job stressors, and particularly interpersonal relationships and management issues, significantly predict nurses' job burnout. Understanding the relative effect of job stressors may help identify fruitful areas for intervention and improve nurse recruitment and retention. © 2017 John Wiley & Sons Ltd.

  16. Occupational stress among Thai emergency department nurses : Development and validation of an instrument for measuring stressors in emergency departments

    OpenAIRE

    Yuwanich, Nuttapol

    2017-01-01

    Working at an emergency department has some characteristics, which may generate stress. In this thesis, the stressors for emergency nurses were evaluated and an instrument was developed for measuring their impact. In order to gain a deeper understanding regarding the occupational stress among emergency nurses, a descriptive qualitative design with semi-structured interviews were used in two studies (I, II), one at a private and the other at a public hospital in Thailand. Three main categories...

  17. Association of Emotional Labor and Occupational Stressors with Depressive Symptoms among Women Sales Workers at a Clothing Shopping Mall in the Republic of Korea: A Cross-Sectional Study.

    Science.gov (United States)

    Chung, Yuh-Jin; Jung, Woo-Chul; Kim, Hyunjoo; Cho, Seong-Sik

    2017-11-23

    In the distribution service industry, sales people often experience multiple occupational stressors such as excessive emotional labor, workplace mistreatment, and job insecurity. The present study aimed to explore the associations of these stressors with depressive symptoms among women sales workers at a clothing shopping mall in Korea. A cross sectional study was conducted on 583 women who consist of clothing sales workers and manual workers using a structured questionnaire to assess demographic factors, occupational stressors, and depressive symptoms. Multiple regression analyses were performed to explore the association of these stressors with depressive symptoms. Scores for job stress subscales such as job demand, job control, and job insecurity were higher among sales workers than among manual workers ( p support was also observed in this model (sβ = -0.09, p = 0.02). The multiple regression analysis stratified by occupation showed that job demand, job insecurity, and workplace mistreatment were significantly associated with depressive symptoms in both occupations ( p support (sβ = -0.22, p women sales workers to prevent depressive symptoms. In particular, promoting social support could be the most effective way to promote women sales workers' mental health.

  18. Stressor Diversity: Introduction and Empirical Integration into the Daily Stress Model

    Science.gov (United States)

    Koffer, Rachel E.; Ram, Nilam; Conroy, David E.; Pincus, Aaron L.; Almeida, David M.

    2016-01-01

    The present study examined if and how stressor diversity, the extent to which one’s stressor events are spread across multiple types of stressors, contributes to daily affective well-being through the adult life span. Stressor diversity was examined as a unique predictor of daily affect and as a moderator of stressor exposure and stressor reactivity effects. Analyses span two independent studies of daily stress: the National Study of Daily Experiences with N=2,022 adults, aged 33–85, assessed over T=8 days, and the Intraindividual Study of Affect, Health, and Interpersonal Behavior with N=150 adults, aged 18–89, assessed over T=63 days. Across both studies, older age was associated with less stressor diversity. Additionally, multivariate multilevel models indicated higher stressor diversity was linked with better affective well-being. Age, however, was not a consistent moderator of such associations. The combination of low stressor diversity and high stressor exposure is discussed as an operationalization of chronic stressors, and this combination was associated with particularly high negative affect and low positive affect. We believe further work will benefit from including both the frequency and diversity of stressor experiences in analyses in order to better characterize individuals’ stressor experiences. PMID:27294713

  19. Stressor diversity: Introduction and empirical integration into the daily stress model.

    Science.gov (United States)

    Koffer, Rachel E; Ram, Nilam; Conroy, David E; Pincus, Aaron L; Almeida, David M

    2016-06-01

    The present study examined whether and how stressor diversity, the extent to which stressor events are spread across multiple types of stressors, contributes to daily affective well-being through the adult life span. Stressor diversity was examined as a unique predictor of daily affect and as a moderator of stressor exposure and stressor reactivity effects. Analyses span 2 independent studies of daily stress: the National Study of Daily Experiences with N = 2,022 adults, aged 33 to 85 years, assessed over T = 8 days, and the Intraindividual Study of Affect, Health, and Interpersonal Behavior with N = 150 adults, aged 18 to 89 years, assessed over T = 63 days. Across both studies, older age was associated with less stressor diversity. Additionally, multivariate multilevel models indicated higher stressor diversity was linked with better affective well-being. Age, however, was not a consistent moderator of such associations. The combination of low stressor diversity and high stressor exposure is discussed as an operationalization of chronic stressors, and this combination was associated with particularly high negative affect and low positive affect. We believe further work will benefit from including both the frequency and diversity of stressor experiences in analyses in order to better characterize individuals' stressor experiences. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  20. A non-linear relationship between the cumulative exposure to occupational stressors and nurses' burnout and the potentially emotion regulation factors.

    Science.gov (United States)

    Sun, Ji-Wei; Lin, Ping-Zhen; Zhang, Hui-Hui; Li, Jia-Huan; Cao, Feng-Lin

    2017-10-08

    Stressful situations can increase the likelihood of nurses experiencing negative emotions, especially burnout. To explore the association of cumulative exposure to occupational stressors and emotion regulation strategies with nurses' burnout. Participants were 602 nurses from three general hospitals in Jinan, China. Social demographic characteristics, occupational stress, burnout, and emotion regulation strategies (cognitive reappraisal, expressive suppression, and rumination), were assessed. Nearly 70% of nurses reported that they were burnt out. Those with a moderate level and high level of stressors were 3.203 times and 26.444 times more likely to have burnout, respectively (x 2 trend = 62.732). Logistic regression revealed that nurses had higher cognitive reappraisal score (odds ratios (OR) = 0.941), scored lower for burnout. Those who had higher expressive suppression score (OR = 1.054), higher rumination score (OR = 1.037), and a higher level of stressors (OR = 2.779-18.259) scored higher for burnout. The results of sensitivity analysis were similar. A non-linear relationship exists between the cumulative exposure to occupational stressors and nurses' burnout. Those who less frequently use cognitive reappraisal, more frequently use rumination and expressive suppression, and have a high level of stressors may be more likely to experience burnout.

  1. Occupational stressors and coping as determinants of burnout in female hospice nurses.

    Science.gov (United States)

    Payne, N

    2001-02-01

    Stressors, coping and demographic variables were examined as predictors of burnout in a sample of hospice nurses. The study aimed to investigate the level of burnout among hospice nurses; to ascertain which aspects of nursing work were positively or negatively related to burnout; to examine the relative contributions made by these different variables and to suggest individual and organizational interventions to reduce levels of burnout. Eighty-nine female nurses from nine hospices completed a battery of questionnaires comprising the Maslach Burnout Inventory, Nursing Stress Scale, Ways of Coping Scale and a demographic information form. In general, the level of burnout (characterized by high emotional exhaustion, high depersonalization of patients and low personal accomplishment) was found to be low. In multiple regression analyses, 'death and dying', "conflict with staff', 'accepting responsibility' and higher nursing grade contributed to emotional exhaustion. 'Conflict with staff', 'inadequate preparation', 'escape' and reduced 'planful problem-solving' contributed to depersonalization. 'Inadequate preparation', 'escape', reduced 'positive reappraisal' and fewer professional qualifications contributed to lower levels of personal accomplishment. Overall, stressors made the greatest contribution to burnout and demographic factors contributed the least. The importance of not labelling individuals as good and bad 'copers' was discussed, as the effectiveness of a strategy may depend on the situation. It was concluded that the investigation of problem-focused and emotion-focused coping in relation to burnout, was oversimplifying the coping-burnout relationship. Suggestions for stress management included staff training in counselling skills, monitoring staff conflict, implementing stress inoculation training to teach appropriate use of coping skills and finally, monitoring particularly vulnerable groups of hospice staff such as unqualified nursing assistants and

  2. Cumulative Risk and Impact Modeling on Environmental Chemical and Social Stressors.

    Science.gov (United States)

    Huang, Hongtai; Wang, Aolin; Morello-Frosch, Rachel; Lam, Juleen; Sirota, Marina; Padula, Amy; Woodruff, Tracey J

    2018-03-01

    The goal of this review is to identify cumulative modeling methods used to evaluate combined effects of exposures to environmental chemicals and social stressors. The specific review question is: What are the existing quantitative methods used to examine the cumulative impacts of exposures to environmental chemical and social stressors on health? There has been an increase in literature that evaluates combined effects of exposures to environmental chemicals and social stressors on health using regression models; very few studies applied other data mining and machine learning techniques to this problem. The majority of studies we identified used regression models to evaluate combined effects of multiple environmental and social stressors. With proper study design and appropriate modeling assumptions, additional data mining methods may be useful to examine combined effects of environmental and social stressors.

  3. The impacts of multiple stressors to model ecological structures

    International Nuclear Information System (INIS)

    Landis, W.G.; Kelly, S.A.; Markiewicz, A.J.; Matthews, R.A.; Matthews, G.B.

    1995-01-01

    The basis of the community conditioning hypothesis is that ecological structures are the result of their unique etiology. Systems that have been exposed to a variety of stressors should reflect this history. The authors how conducted a series of microcosm experiments that can compare the effects of multiple stressors upon community dynamics. The microcosm protocols are derived from the Standardized Aquatic Microcosm (SAM) and have Lemma and additional protozoan species. Two multiple stressor experiments have been conducted. In an extended length SAM (ELSAM), two of four treatments were dosed with the turbine fuel JP-8 one week into the experiment. Two treatments were later exposed to the heat stress, one that had received jet fuel and one that had not. Similarly, an ELSAM was conducted with the second stressor being the further addition of JP-8 replacing the heat shock. Biological, physical and chemical data were analyzed with multivariate techniques including nonmetric clustering and association analysis. Space-time worms and phase diagrams were also employed to ascertain the dynamic relationships of variables identified as important by the multivariate techniques. The experiments do not result in a simple additive linear response to the additional stressor. Examination of the relative population dynamics reveal alterations in trajectories that suggest treatment related effects. As in previous single stressor experiments, recovery does not occur even after extended experimental periods. The authors are now attempting to measure the resulting trajectories, changes in similarity vectors and overall dynamics. However, community conditioning does appear to be an important framework in understanding systems with a heterogeneous array of stressors

  4. Benthic macroinvertebrates and multiple stressors : quantification of the effects of multiple stressors in field, laboratory and model settings

    NARCIS (Netherlands)

    Peeters, E.T.H.M.

    2001-01-01

    Organisms are always exposed to several simultaneously operating stressors in nature. It appears that the combined effects of multiple stressors cannot be understood as a simple product of their individual effects. To understand how multiple stressors affect the composition and functioning

  5. An improved null model for assessing the net effects of multiple stressors on communities.

    Science.gov (United States)

    Thompson, Patrick L; MacLennan, Megan M; Vinebrooke, Rolf D

    2018-01-01

    Ecological stressors (i.e., environmental factors outside their normal range of variation) can mediate each other through their interactions, leading to unexpected combined effects on communities. Determining whether the net effect of stressors is ecologically surprising requires comparing their cumulative impact to a null model that represents the linear combination of their individual effects (i.e., an additive expectation). However, we show that standard additive and multiplicative null models that base their predictions on the effects of single stressors on community properties (e.g., species richness or biomass) do not provide this linear expectation, leading to incorrect interpretations of antagonistic and synergistic responses by communities. We present an alternative, the compositional null model, which instead bases its predictions on the effects of stressors on individual species, and then aggregates them to the community level. Simulations demonstrate the improved ability of the compositional null model to accurately provide a linear expectation of the net effect of stressors. We simulate the response of communities to paired stressors that affect species in a purely additive fashion and compare the relative abilities of the compositional null model and two standard community property null models (additive and multiplicative) to predict these linear changes in species richness and community biomass across different combinations (both positive, negative, or opposite) and intensities of stressors. The compositional model predicts the linear effects of multiple stressors under almost all scenarios, allowing for proper classification of net effects, whereas the standard null models do not. Our findings suggest that current estimates of the prevalence of ecological surprises on communities based on community property null models are unreliable, and should be improved by integrating the responses of individual species to the community level as does our

  6. A geospatial modelling approach to predict seagrass habitat recovery under multiple stressor regimes

    Science.gov (United States)

    Restoration of estuarine seagrass habitats requires a clear understanding of the modes of action of multiple interacting stressors including nutrients, climate change, coastal land-use change, and habitat modification. We have developed and demonstrated a geospatial modeling a...

  7. Occupant Protection Data Mining and Modeling Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Current National Aeronautics and Space Administration (NASA) occupant protection standards and requirements are based on extrapolations of biodynamic models, which...

  8. Relations of occupational stress to occupational class in Japanese civil servants : analysis by two occupational stress models

    OpenAIRE

    Kawaharada, Mariko; Saijo, Yasuaki; Yoshioka, Eiji; Sato, Tetsuro; Sato, Hirokazu; Kishi, Reiko

    2007-01-01

    The aim of the present study was to identify relations between occupational stress and occupational class in Japanese civil servants, using two occupational stress models – the Effort-Reward Imbalance (ERI) Model and the Job Demand-Control (JDC) Model. The subjects were employees of three local public organizations. We distributed self-administered questionnaires and assessed occupational stress by ERI and JDC. We used seven occupational categories based on the Standard Occupational Classific...

  9. An exploratory study to identify the range of occupational stressors that occur among ambulance workers in Johannesburg

    OpenAIRE

    2012-01-01

    M.A. This study looks into the types of stressors specific to the Emergency Medical Services. The study was undertaken over a period of two years with the following objectives: • A literature survey regarding stress, organisational stress in general and stress in the context of Emergency Medical Services in particular. • An investigation of the personnel of the Emergency Medical Services to ascertain the stressors perceived as stressful by them. • Recommendations on how to prevent or lower...

  10. Responding to Trauma at Sea: A Case Study in Psychological First Aid, Unique Occupational Stressors, and Resiliency Self-Care.

    Science.gov (United States)

    Millegan, Jeffrey; Delaney, Eileen M; Klam, Warren

    2016-11-01

    The U.S. Navy deploys Special Psychiatric Rapid Intervention Teams (SPRINT) to sites of military disasters to assist survivors and the command. SPRINT functions primarily as a consultant to help commands effectively respond to the mental health needs of their service members following a traumatic event. Utilizing the principles of psychological first aid, the overall goal of SPRINT is to mitigate long-term mental health dysfunction and facilitate recovery at both the individual and unit level. We present a case study of a SPRINT mission to a deployed U.S. Navy ship in response to a cluster of suicides and subsequent concerns about the well-being of the remaining crew. Throughout this mission, important themes emerged, such as the impact of accumulated operational stressors and the subsequent development of mental health stigma. Also, this case study demonstrates the potential effectiveness of introducing resiliency self-care meditation training to remote environments that lack ready access to mental health resources. From here, SPRINT can provide a model for immediate disaster mental health response that has potential relevancy beyond the military. Reprint & Copyright © 2016 Association of Military Surgeons of the U.S.

  11. The dynamics of life stressors and depressive symptoms in early adolescence: a test of six theoretical models.

    Science.gov (United States)

    Clements, Margaret; Aber, J Lawrence; Seidman, Edward

    2008-01-01

    Structural equation modeling was used to compare 6 competing theoretically based psychosocial models of the longitudinal association between life stressors and depressive symptoms in a sample of early adolescents (N= 907; 40% Hispanic, 32% Black, and 19% White; mean age at Time 1 = 11.4 years). Only two models fit the data, both of which included paths modeling the effect of depressive symptoms on stressors recall: The mood-congruent cognitive bias model included only depressive symptoms to life stressors paths (DS-->S), whereas the fully transactional model included paths representing both the DS-->S and stressors to depressive symptoms (S-->DS) effects. Social causation models and the stress generation model did not fit the data. Findings demonstrate the importance of accounting for mood-congruent cognitive bias in stressors-depressive symptoms investigations.

  12. Data linkage between the National Birth Defects Prevention Study and the Occupational Information Network (O*NET) to assess workplace physical activity, sedentary behaviors, and emotional stressors during pregnancy.

    Science.gov (United States)

    Lee, Laura J; Symanski, Elaine; Lupo, Philip J; Tinker, Sarah C; Razzaghi, Hilda; Pompeii, Lisa A; Hoyt, Adrienne T; Canfield, Mark A; Chan, Wenyaw

    2016-02-01

    Knowledge of the prevalence of work-related physical activities, sedentary behaviors, and emotional stressors among pregnant women is limited, and the extent to which these exposures vary by maternal characteristics remains unclear. Data on mothers of 6,817 infants without major birth defects, with estimated delivery during 1997 through 2009 who worked during pregnancy were obtained from the National Birth Defects Prevention Study. Information on multiple domains of occupational exposures was gathered by linking mother's primary job to the Occupational Information Network Version 9.0. The most frequent estimated physical activity associated with jobs during pregnancy was standing. Of 6,337 mothers, 31.0% reported jobs associated with standing for ≥75% of their time. There was significant variability in estimated occupational exposures by maternal age, race/ethnicity, and educational level. Our findings augment existing literature on occupational physical activities, sedentary behaviors, emotional stressors, and occupational health disparities during pregnancy. © 2015 Wiley Periodicals, Inc.

  13. Spatial occupancy models for large data sets

    Science.gov (United States)

    Johnson, Devin S.; Conn, Paul B.; Hooten, Mevin B.; Ray, Justina C.; Pond, Bruce A.

    2013-01-01

    Since its development, occupancy modeling has become a popular and useful tool for ecologists wishing to learn about the dynamics of species occurrence over time and space. Such models require presence–absence data to be collected at spatially indexed survey units. However, only recently have researchers recognized the need to correct for spatially induced overdisperison by explicitly accounting for spatial autocorrelation in occupancy probability. Previous efforts to incorporate such autocorrelation have largely focused on logit-normal formulations for occupancy, with spatial autocorrelation induced by a random effect within a hierarchical modeling framework. Although useful, computational time generally limits such an approach to relatively small data sets, and there are often problems with algorithm instability, yielding unsatisfactory results. Further, recent research has revealed a hidden form of multicollinearity in such applications, which may lead to parameter bias if not explicitly addressed. Combining several techniques, we present a unifying hierarchical spatial occupancy model specification that is particularly effective over large spatial extents. This approach employs a probit mixture framework for occupancy and can easily accommodate a reduced-dimensional spatial process to resolve issues with multicollinearity and spatial confounding while improving algorithm convergence. Using open-source software, we demonstrate this new model specification using a case study involving occupancy of caribou (Rangifer tarandus) over a set of 1080 survey units spanning a large contiguous region (108 000 km2) in northern Ontario, Canada. Overall, the combination of a more efficient specification and open-source software allows for a facile and stable implementation of spatial occupancy models for large data sets.

  14. Determining ecoregional numeric nutrient criteria by stressor-response models in Yungui ecoregion lakes, China.

    Science.gov (United States)

    Huo, Shouliang; Ma, Chunzi; Xi, Beidou; Tong, Zhonghua; He, Zhuoshi; Su, Jing; Wu, Fengchang

    2014-01-01

    The importance of developing numeric nutrient criteria has been recognized to protect the designated uses of water bodies from nutrient enrichment that is associated with broadly occurring levels of nitrogen/phosphorus pollution. The identification and estimation of stressor-response models in aquatic ecosystems has been shown to be useful in the determination of nutrient criteria. In this study, three methods based on stressor-response relationships were applied to determine nutrient criteria for Yungui ecoregion lakes with respect to total phosphorus (TP), total nitrogen (TN), and planktonic chlorophyll a (Chl a). Simple linear regression (SLR) models were established to provide an estimate of the relationship between a response variable and a stressor. Multiple linear regressions were used to simultaneously estimate the effect of TP and TN on Chl a. A morphoedaphic index (MEI) was applied to derive nutrient criteria using data from Yungui ecoregion lakes, which were considered as areas with less anthropogenic influences. Nutrient criteria, as determined by these three methods, showed broad agreement for all parameters. The ranges of numeric nutrient criteria for Yungui ecoregion lakes were determined as follows: TP 0.008-0.010 mg/L and TN 0.140-0.178 mg/L. The stressor-response analysis described will be of benefit to support countries in their numeric criteria development programs and to further the goal of reducing nitrogen/phosphorus pollution in China.

  15. Participation and occupation in occupational therapy models of practice: A discussion of possibilities and challenges.

    Science.gov (United States)

    Larsson-Lund, Maria; Nyman, Anneli

    2017-11-01

    Occupation has been the focus in occupational therapy practice to greater or lesser degrees from a historical viewpoint. This evokes a need to discuss whether concepts that are added to our field will enhance or blur our focus on occupation. To explore how the concept of participation in the International Classification of Functioning, Disability and Health (ICF) is related to the concept of occupation by reviewing and comparing its use in three models of practice within occupational therapy. The aim was also to generate discussion on possibilities and challenges concerning the relationship of participation and occupation. The models reviewed were The Model of Human Occupation (MOHO), the Canadian Model of Occupational Performance and Engagement (CMOP-E) and the Occupational Therapy Intervention Process Model (OTIPM). The concept of participation was related to occupation in different ways in these models. Based on the review some challenges and considerations for occupational therapy were generated. Relating the concept of participation from the ICF to the concept of occupation in models of practice can be challenging. At the same time, relating the concepts can be a resource to develop occupational therapy and the understanding of occupational issues in society.

  16. Dual diathesis-stressor model of emotional and linguistic contributions to developmental stuttering.

    Science.gov (United States)

    Walden, Tedra A; Frankel, Carl B; Buhr, Anthony P; Johnson, Kia N; Conture, Edward G; Karrass, Jan M

    2012-05-01

    This study assessed emotional and speech-language contributions to childhood stuttering. A dual diathesis-stressor framework guided this study, in which both linguistic requirements and skills, and emotion and its regulation, are hypothesized to contribute to stuttering. The language diathesis consists of expressive and receptive language skills. The emotion diathesis consists of proclivities to emotional reactivity and regulation of emotion, and the emotion stressor consists of experimentally manipulated emotional inductions prior to narrative speaking tasks. Preschool-age children who do and do not stutter were exposed to three emotion-producing overheard conversations-neutral, positive, and angry. Emotion and emotion-regulatory behaviors were coded while participants listened to each conversation and while telling a story after each overheard conversation. Instances of stuttering during each story were counted. Although there was no main effect of conversation type, results indicated that stuttering in preschool-age children is influenced by emotion and language diatheses, as well as coping strategies and situational emotional stressors. Findings support the dual diathesis-stressor model of stuttering.

  17. Cultural Stressors and the Hopelessness Model of Depressive Symptoms in Latino Adolescents

    Science.gov (United States)

    Stein, Gabriela L.; Gonzalez, Laura M.; Huq, Nadia

    2012-01-01

    Depressive symptoms in Latino youth have been related to both culturally-universal and culturally-based stressors. However, few studies have examined the unique contributions of culturally-based stressors above and beyond other types of stressors. Moreover, no past studies with Latinos have examined the role of culturally-based stressors within a…

  18. Translational relevance of rodent models of hypothalamic-pituitary-adrenal function and stressors in adolescence

    Directory of Open Access Journals (Sweden)

    Cheryl M. McCormick

    2017-02-01

    Full Text Available Elevations in glucocorticoids that result from environmental stressors can have programming effects on brain structure and function when the exposure occurs during sensitive periods that involve heightened neural development. In recent years, adolescence has gained increasing attention as another sensitive period of development, a period in which pubertal transitions may increase the vulnerability to stressors. There are similarities in physical and behavioural development between humans and rats, and rats have been used effectively as an animal model of adolescence and the unique plasticity of this period of ontogeny. This review focuses on benefits and challenges of rats as a model for translational research on hypothalamic-pituitary-adrenal (HPA function and stressors in adolescence, highlighting important parallels and contrasts between adolescent rats and humans, and we review the main stress procedures that are used in investigating HPA stress responses and their consequences in adolescence in rats. We conclude that a greater focus on timing of puberty as a factor in research in adolescent rats may increase the translational relevance of the findings.

  19. Tools for organisational risk evaluation for occupational health stressors (OREOHS) for the small-scale mining industry

    CSIR Research Space (South Africa)

    Edwards, AL

    2009-07-01

    Full Text Available access to knowledge and tools that will raise awareness and disseminate affordable, best practice methods for use by small-scale mines. With this in mind, the CSIR Occupational Health and Ergonomics research group have developed the OREOHS tool which is a...

  20. Correspondence model of occupational accidents

    Directory of Open Access Journals (Sweden)

    Juan C. Conte

    2011-09-01

    Full Text Available We present a new generalized model for the diagnosis and prediction of accidents among the Spanish workforce. Based on observational data of the accident rate in all Spanish companies over eleven years (7,519,732 accidents, we classified them in a new risk-injury contingency table (19×19. Through correspondence analysis, we obtained a structure composed of three axes whose combination identifies three separate risk and injury groups, which we used as a general Spanish pattern. The most likely or frequent relationships between the risk and injuries identified in the pattern facilitated the decision-making process in companies at an early stage of risk assessment. Each risk-injury group has its own characteristics, which are understandable within the phenomenological framework of the accident. The main advantages of this model are its potential application to any other country and the feasibility of contrasting different country results. One limiting factor, however, is the need to set a common classification framework for risks and injuries to enhance comparison, a framework that does not exist today. The model aims to manage work-related accidents automatically at any level.Apresentamos aqui um modelo generalizado para o diagnóstico e predição de acidentes na classe de trabalhadores da Espanha. Baseados em dados sobre a frequência de acidentes em todas as companhias da Espanha em 11 anos (7.519.732 acidentes, nós os classificamos em uma nova tabela de contingência risco-injúria (19×19. Através de uma análise por correspondência obtivemos uma estrutura composta por 3 eixos cuja combinação identifica 3 grupos separados de risco e injúria, que nós usamos como um perfil geral na Espanha. As mais prováveis ou frequentes relações entre risco e injúrias identificadas nesse perfil facilitaram o processo de decisão nas companhias em um estágio inicial de apreciação do risco. Cada grupo de risco-injúria tem suas próprias caracter

  1. Occupational stress in the armed forces: An Indian army perspective

    Directory of Open Access Journals (Sweden)

    Sakshi Sharma

    2015-09-01

    Full Text Available This study attempts to explore factors influencing occupational stress faced by Indian army soldiers and evaluate applicability of the scale used for measuring occupational stressors. Structured interview schedules were used to collect first hand data from a sample of 415 soldiers. Exploratory Factor Analysis (EFA highlights lack of control at work, role conflict, inadequate awareness about profession, workload and job pressure, and indifferent organisational attitude as the major occupational stressors in the Indian army. In addition, Confirmatory Factor Analysis (CFA confirms occupational stressor as an eight factor model in the army. The study recommends implementing commitment-based management approach and techniques such as Sahaja Yoga meditation in the army.

  2. Quantitative occupational risk model: Single hazard

    International Nuclear Information System (INIS)

    Papazoglou, I.A.; Aneziris, O.N.; Bellamy, L.J.; Ale, B.J.M.; Oh, J.

    2017-01-01

    A model for the quantification of occupational risk of a worker exposed to a single hazard is presented. The model connects the working conditions and worker behaviour to the probability of an accident resulting into one of three types of consequence: recoverable injury, permanent injury and death. Working conditions and safety barriers in place to reduce the likelihood of an accident are included. Logical connections are modelled through an influence diagram. Quantification of the model is based on two sources of information: a) number of accidents observed over a period of time and b) assessment of exposure data of activities and working conditions over the same period of time and the same working population. Effectiveness of risk reducing measures affecting the working conditions, worker behaviour and/or safety barriers can be quantified through the effect of these measures on occupational risk. - Highlights: • Quantification of occupational risk from a single hazard. • Influence diagram connects working conditions, worker behaviour and safety barriers. • Necessary data include the number of accidents and the total exposure of worker • Effectiveness of risk reducing measures is quantified through the impact on the risk • An example illustrates the methodology.

  3. Modelling coral reef futures to inform management: can reducing local-scale stressors conserve reefs under climate change?

    Science.gov (United States)

    Gurney, Georgina G; Melbourne-Thomas, Jessica; Geronimo, Rollan C; Aliño, Perry M; Johnson, Craig R

    2013-01-01

    Climate change has emerged as a principal threat to coral reefs, and is expected to exacerbate coral reef degradation caused by more localised stressors. Management of local stressors is widely advocated to bolster coral reef resilience, but the extent to which management of local stressors might affect future trajectories of reef state remains unclear. This is in part because of limited understanding of the cumulative impact of multiple stressors. Models are ideal tools to aid understanding of future reef state under alternative management and climatic scenarios, but to date few have been sufficiently developed to be useful as decision support tools for local management of coral reefs subject to multiple stressors. We used a simulation model of coral reefs to investigate the extent to which the management of local stressors (namely poor water quality and fishing) might influence future reef state under varying climatic scenarios relating to coral bleaching. We parameterised the model for Bolinao, the Philippines, and explored how simulation modelling can be used to provide decision support for local management. We found that management of water quality, and to a lesser extent fishing, can have a significant impact on future reef state, including coral recovery following bleaching-induced mortality. The stressors we examined interacted antagonistically to affect reef state, highlighting the importance of considering the combined impact of multiple stressors rather than considering them individually. Further, by providing explicit guidance for management of Bolinao's reef system, such as which course of management action will most likely to be effective over what time scales and at which sites, we demonstrated the utility of simulation models for supporting management. Aside from providing explicit guidance for management of Bolinao's reef system, our study offers insights which could inform reef management more broadly, as well as general understanding of reef

  4. Modelling coral reef futures to inform management: can reducing local-scale stressors conserve reefs under climate change?

    Directory of Open Access Journals (Sweden)

    Georgina G Gurney

    Full Text Available Climate change has emerged as a principal threat to coral reefs, and is expected to exacerbate coral reef degradation caused by more localised stressors. Management of local stressors is widely advocated to bolster coral reef resilience, but the extent to which management of local stressors might affect future trajectories of reef state remains unclear. This is in part because of limited understanding of the cumulative impact of multiple stressors. Models are ideal tools to aid understanding of future reef state under alternative management and climatic scenarios, but to date few have been sufficiently developed to be useful as decision support tools for local management of coral reefs subject to multiple stressors. We used a simulation model of coral reefs to investigate the extent to which the management of local stressors (namely poor water quality and fishing might influence future reef state under varying climatic scenarios relating to coral bleaching. We parameterised the model for Bolinao, the Philippines, and explored how simulation modelling can be used to provide decision support for local management. We found that management of water quality, and to a lesser extent fishing, can have a significant impact on future reef state, including coral recovery following bleaching-induced mortality. The stressors we examined interacted antagonistically to affect reef state, highlighting the importance of considering the combined impact of multiple stressors rather than considering them individually. Further, by providing explicit guidance for management of Bolinao's reef system, such as which course of management action will most likely to be effective over what time scales and at which sites, we demonstrated the utility of simulation models for supporting management. Aside from providing explicit guidance for management of Bolinao's reef system, our study offers insights which could inform reef management more broadly, as well as general

  5. Modelling Coral Reef Futures to Inform Management: Can Reducing Local-Scale Stressors Conserve Reefs under Climate Change?

    Science.gov (United States)

    Gurney, Georgina G.; Melbourne-Thomas, Jessica; Geronimo, Rollan C.; Aliño, Perry M.; Johnson, Craig R.

    2013-01-01

    Climate change has emerged as a principal threat to coral reefs, and is expected to exacerbate coral reef degradation caused by more localised stressors. Management of local stressors is widely advocated to bolster coral reef resilience, but the extent to which management of local stressors might affect future trajectories of reef state remains unclear. This is in part because of limited understanding of the cumulative impact of multiple stressors. Models are ideal tools to aid understanding of future reef state under alternative management and climatic scenarios, but to date few have been sufficiently developed to be useful as decision support tools for local management of coral reefs subject to multiple stressors. We used a simulation model of coral reefs to investigate the extent to which the management of local stressors (namely poor water quality and fishing) might influence future reef state under varying climatic scenarios relating to coral bleaching. We parameterised the model for Bolinao, the Philippines, and explored how simulation modelling can be used to provide decision support for local management. We found that management of water quality, and to a lesser extent fishing, can have a significant impact on future reef state, including coral recovery following bleaching-induced mortality. The stressors we examined interacted antagonistically to affect reef state, highlighting the importance of considering the combined impact of multiple stressors rather than considering them individually. Further, by providing explicit guidance for management of Bolinao's reef system, such as which course of management action will most likely to be effective over what time scales and at which sites, we demonstrated the utility of simulation models for supporting management. Aside from providing explicit guidance for management of Bolinao's reef system, our study offers insights which could inform reef management more broadly, as well as general understanding of reef

  6. A Model of Chronic Exposure to Unpredictable Mild Socio-Environmental Stressors Replicates Some Spaceflight-Induced Immunological Changes

    Directory of Open Access Journals (Sweden)

    Fanny Gaignier

    2018-05-01

    Full Text Available During spaceflight, astronauts face radiations, mechanical, and socio-environmental stressors. To determine the impact of chronic socio-environmental stressors on immunity, we exposed adult male mice to chronic unpredictable mild psychosocial and environmental stressors (CUMS model for 3 weeks. This duration was chosen to simulate a long flight at the human scale. Our data show that this combination of stressors induces an increase of serum IgA, a reduction of normalized splenic mass and tends to reduce the production of pro-inflammatory cytokines, as previously reported during or after space missions. However, CUMS did not modify major splenic lymphocyte sub-populations and the proliferative responses of splenocytes suggesting that these changes could be due to other factors such as gravity changes. Thus, CUMS, which is an easy to implement model, could contribute to deepen our understanding of some spaceflight-associated immune alterations and could be useful to test countermeasures.

  7. Stressor-response modeling using the 2D water quality model and regression trees to predict chlorophyll-a in a reservoir system

    Science.gov (United States)

    In order to control algal blooms, stressor-response relationships between water quality metrics, environmental variables, and algal growth should be understood and modeled. Machine-learning methods were suggested to express stressor-response relationships found by application of mechanistic water qu...

  8. Work stressors, depressive symptoms and sleep quality among US Navy members: a parallel process latent growth modelling approach across deployment.

    Science.gov (United States)

    Bravo, Adrian J; Kelley, Michelle L; Swinkels, Cindy M; Ulmer, Christi S

    2017-11-03

    The present study examined whether work stressors contribute to sleep problems and depressive symptoms over the course of deployment (i.e. pre-deployment, post-deployment and 6-month reintegration) among US Navy members. Specifically, we examined whether depressive symptoms or sleep quality mediate the relationships between work stressors and these outcomes. Participants were 101 US Navy members who experienced an 8-month deployment after Operational Enduring Freedom/Operation Iraqi Freedom. Using piecewise latent growth models, we found that increased work stressors were linked to increased depressive symptoms and decreased sleep quality across all three deployment stages. Further, increases in work stressors from pre- to post-deployment contributed to poorer sleep quality post-deployment via increasing depressive symptoms. Moreover, sleep quality mediated the association between increases in work stressors and increases in depressive symptoms from pre- to post-deployment. These effects were maintained from post-deployment through the 6-month reintegration. Although preliminary, our results suggest that changes in work stressors may have small, but significant implications for both depressive symptoms and quality of sleep over time, and a bi-directional relationship persists between sleep quality and depression across deployment. Strategies that target both stress and sleep could address both precipitating and perpetuating factors that affect sleep and depressive symptoms. © 2017 European Sleep Research Society.

  9. Effect of emotional dissonance on organizational citizenship behavior: testing the stressor-strain-outcome model.

    Science.gov (United States)

    Cheung, Francis Yue-Lok; Cheung, Ray Yu-Hin

    2013-01-01

    In this study, the stressor-strain-outcome (SSO) model developed by Koeske and Koeske was adopted to examine the mediating effect of burnout between emotional dissonance and organizational citizenship behavior (OCB). The study involved 264 full-time Chinese school teachers (82 men, 16 women, and 22 individuals whose genders were not specified; mean age = 34.4 years and SD = 8.09 years). Correlation analysis showed that emotional dissonance is positively related to all three burnout dimensions (i.e., emotional exhaustion, depersonalization, and lack of personal accomplishment). Emotional dissonance is also negatively related to OCB toward individuals. Results from structural equation modeling support the SSO model, which states that emotional dissonance first leads to burnout and then to lower OCB. The limitations and implications to the school management, such as provision of emotional regulation training and strengthening of the social network system, were also discussed.

  10. Studying historical occupational careers with multilevel growth models

    NARCIS (Netherlands)

    Schulz, W.; Maas, I.

    2010-01-01

    In this article we propose to study occupational careers with historical data by using multilevel growth models. Historical career data are often characterized by a lack of information on the timing of occupational changes and by different numbers of observations of occupations per individual.

  11. Modeling occupants in far-side impacts.

    Science.gov (United States)

    Douglas, Clay; Fildes, Brian; Gibson, Tom

    2011-10-01

    Far-side impacts are not part of any regulated NCAP, FMVSS, or similar test regime despite accounting for 43 percent of the seriously injured persons and 30 percent of the harm in U.S. side impact crashes. Furthermore, injuries to the head and thorax account for over half of the serious injuries sustained by occupants in far-side crashes. Despite this, there is no regulated or well-accepted anthropomorphic test device (ATD) or computer model available to investigate far-side impacts. As such, this presents an opportunity to assess a computer model that can be used to measure the effect of varying restraint parameters on occupant biomechanics in far-side impacts. This study sets out to demonstrate the modified TASS human facet model's (MOTHMO) capabilities in modeling whole-body response in far-side impacts. MOTHMO's dynamic response was compared to that of postmortem human subjects (PMHS), WorldSID, and Thor-NT in a series of far-side sled tests. The advantages, disadvantages, and differences of using MOTHMO compared to ATDs were highlighted and described in terms of model design and instrumentation. Potential applications and improvements for MOTHMO were also recommended. The results showed that MOTHMO is capable of replicating the seat belt-to-shoulder complex interaction, pelvis impacts, head displacement, neck and shoulder belt loading from inboard mounted belts, and impacts from multiple directions. Overall, the model performed better than Thor-NT and at least as well as WorldSID when compared to PMHS results. Though WorldSID and Thor-NT ATDs were capable of reproducing many of these impact loads, measuring the seat belt-to-shoulder complex interaction and thoracic deflection at multiple sites and directions was less accurately handled. This study demonstrated that MOTHMO is capable of modeling whole-body response in far-side impacts. Furthermore, MOTHMO can be used as a virtual design tool to explore the effect of varying restraint parameters on occupant

  12. Stressor-Response Models Relating Nutrient Enrichment to Algal Communities in Pacific Northwest Streams and Rivers

    Science.gov (United States)

    Sobota, D. J.; Hubler, S.; Paul, M. J.; Labiosa, R.

    2015-12-01

    Excessive algal growth in streams and rivers from nutrient enrichment can cause costly human health and environmental problems. As part of the US Environmental Protection Agency's Nutrient Scientific Technical Exchange Partnership and Support (N-STEPS) program, we have been developing stressor-response (S-R) models relating nutrients to attached algal (periphyton) communities to help prioritize monitoring for water quality impairments in Oregon (Pacific Northwest, USA) streams and rivers. Existing data from the state and neighboring states were compiled and standardized from the Oregon Department of Environmental Quality, US Environmental Protection Agency, and the US Geological Survey. To develop S-R models, algal community and biomass metrics were compared with nitrogen (N) and phosphorus (P) concentration data, including total, dissolved, and inorganic forms of these nutrients. In total, 928 paired algal-nutrient samples were compiled from the 8 Level-III Ecoregions occurring in Oregon. Relationships between algal biomass metrics and nutrient concentrations were weak, with only ash-free dry mass and standing stock of chlorophyll a showing slight positive relationships across gradients of total N and soluble reactive P concentrations, respectively. In contrast, metrics describing algal community composition, including percent diatoms and abundance of nutrient-sensitive species, showed very strong nonlinear relationships with total N or P concentrations. This suggests that data describing algal community composition can help identify specific nutrient stressors across environmentally-diverse streams and rivers in the Pacific Northwest. Future analyses will examine if nutrient-algal S-R models vary across different hydrological, physiographical, and ecological settings in the region.

  13. Investigating the Relationships among Stressors, Stress Level, and Mental Symptoms for Infertile Patients: A Structural Equation Modeling Approach.

    Directory of Open Access Journals (Sweden)

    Jong-Yi Wang

    Full Text Available Patients with infertility are a high risk group in depression and anxiety. However, an existing theoretically and empirically validated model of stressors, stress, and mental symptoms specific for infertile patients is still a void. This study aimed to determine the related factors and their relational structures that affect the level of depressive and anxiety symptoms among infertile patients.A cross-sectional sample of 400 infertility outpatients seeking reproduction treatments in three teaching hospitals across Taiwan participated in the structured questionnaire survey in 2011. The hypothesized model comprising 10 latent variables was tested by Structural Equation Modeling using AMOS 17.Goodness-of-fit indexes, including χ2/DF = 1.871, PGFI = 0.746, PNFI = 0.764, and others, confirmed the modified model fit the data well. Marital stressor, importance of children, guilt-and-blame, and social stressor showed a direct effect on perceived stress. Instead of being a factor of stress, social support was directly and positively related to self-esteem. Perceived stress and self-esteem were the two major mediators for the relationships between stressors and mental symptoms. Increase in social support and self-esteem led to decrease in mental symptoms among the infertile patients.The relational structures were identified and named as the Stressors Stress Symptoms Model, clinically applied to predict anxiety and depression from various stressors. Assessing sources and level of infertility-related stress and implementing culturally-sensitive counseling with an emphasis on positive personal value may assist in preventing the severity of depression and anxiety.

  14. Investigating the Relationships among Stressors, Stress Level, and Mental Symptoms for Infertile Patients: A Structural Equation Modeling Approach.

    Science.gov (United States)

    Wang, Jong-Yi; Li, Yi-Shan; Chen, Jen-De; Liang, Wen-Miin; Yang, Tung-Chuan; Lee, Young-Chang; Wang, Chia-Woei

    2015-01-01

    Patients with infertility are a high risk group in depression and anxiety. However, an existing theoretically and empirically validated model of stressors, stress, and mental symptoms specific for infertile patients is still a void. This study aimed to determine the related factors and their relational structures that affect the level of depressive and anxiety symptoms among infertile patients. A cross-sectional sample of 400 infertility outpatients seeking reproduction treatments in three teaching hospitals across Taiwan participated in the structured questionnaire survey in 2011. The hypothesized model comprising 10 latent variables was tested by Structural Equation Modeling using AMOS 17. Goodness-of-fit indexes, including χ2/DF = 1.871, PGFI = 0.746, PNFI = 0.764, and others, confirmed the modified model fit the data well. Marital stressor, importance of children, guilt-and-blame, and social stressor showed a direct effect on perceived stress. Instead of being a factor of stress, social support was directly and positively related to self-esteem. Perceived stress and self-esteem were the two major mediators for the relationships between stressors and mental symptoms. Increase in social support and self-esteem led to decrease in mental symptoms among the infertile patients. The relational structures were identified and named as the Stressors Stress Symptoms Model, clinically applied to predict anxiety and depression from various stressors. Assessing sources and level of infertility-related stress and implementing culturally-sensitive counseling with an emphasis on positive personal value may assist in preventing the severity of depression and anxiety.

  15. Representation of occupational information across resources and validation of the occupational data for health model.

    Science.gov (United States)

    Rajamani, Sripriya; Chen, Elizabeth S; Lindemann, Elizabeth; Aldekhyyel, Ranyah; Wang, Yan; Melton, Genevieve B

    2018-02-01

    Reports by the National Academy of Medicine and leading public health organizations advocate including occupational information as part of an individual's social context. Given recent National Academy of Medicine recommendations on occupation-related data in the electronic health record, there is a critical need for improved representation. The National Institute for Occupational Safety and Health has developed an Occupational Data for Health (ODH) model, currently in draft format. This study aimed to validate the ODH model by mapping occupation-related elements from resources representing recommendations, standards, public health reports and surveys, and research measures, along with preliminary evaluation of associated value sets. All 247 occupation-related items across 20 resources mapped to the ODH model. Recommended value sets had high variability across the evaluated resources. This study demonstrates the ODH model's value, the multifaceted nature of occupation information, and the critical need for occupation value sets to support clinical care, population health, and research. © The Author 2017. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  16. Investigations of HPA Function and the Enduring Consequences of Stressors in Adolescence in Animal Models

    Science.gov (United States)

    McCormick, Cheryl M.; Mathews, Iva Z.; Thomas, Catherine; Waters, Patti

    2010-01-01

    Developmental differences in hypothalamic-pituitary-adrenal (HPA) axis responsiveness to stressors and ongoing development of glucocorticoid-sensitive brain regions in adolescence suggest that similar to the neonatal period of ontogeny, adolescence may also be a sensitive period for programming effects of stressors on the central nervous system.…

  17. Study on a model for future occupational health: proposal for an occupational health service model in Japan.

    Science.gov (United States)

    Higashi, Toshiaki

    2006-10-01

    The Study Model for Future Occupational Health (funded by a research grant from the Ministry of Health, Welfare and Labor) is a joint research project involving various organizations and agencies undertaken from 2002 to 2004. Society has undergone a dramatic transformation due to technological developments and internationalization. At the same time a low birth rate and an aging population have resulted in an increase in both the percentage of workers experiencing strong anxiety and stress in relation to their jobs and the working environment and the number of suicides. As a natural consequence, occupational health services are now expected to provide EAP, consulting and other functions that were formerly considered outside the realm of occupational health. In consideration of this background, the present study propose the following issues to provide a model for future occupational health services that meet the conditions presently confronted by each worker. 1. How to provide occupational health services and occupational physicians' services: 1) a basic time of 20 minutes of occupational health services per year should be allotted to each worker and to all workers; 2) the obligatory regulations should be revised to expand the obligation from businesses each with 50 or more employees under the present laws to businesses each with 30 or more employees. 2. Providers of occupational health services and occupational physicians' services: (1) reinforcement of outside occupational health agencies; (2) fostering occupational health consultant firms; (3) development of an institute of occupational safety and health; (4) support of activities by authorized occupational physicians in the field; (5) expanding of joint selection of occupational physicians including subsidy increase and the extension of a period of subsidy to five hears; (6) licensing of new entry into occupational health undertaking. 3. Introduction of new report system: (1) establishment of the obligation to

  18. Empirically-based modeling and mapping to consider the co-occurrence of ecological receptors and stressors

    Science.gov (United States)

    Part of the ecological risk assessment process involves examining the potential for environmental stressors and ecological receptors to co-occur across a landscape. In this study, we introduce a Bayesian joint modeling framework for use in evaluating and mapping the co-occurrence...

  19. Role stressors and job attitudes: a mediated model of leader-member exchange.

    Science.gov (United States)

    Zhang, Rui-Ping; Tsingan, Li; Zhang, Long-Ping

    2013-01-01

    Workers with high levels of role stressors have been known to report low job satisfaction and high turnover intention. However, how the role stressors-job attitudes relationship is influenced by leader-member exchange has hardly been studied. This study examined the effect of leader-member exchange (leader support) on the relationship between chronic role stressors (i.e., role ambiguity and role conflict) and job attitudes (i.e., job satisfaction and turnover intention). Employees (N = 162) who enrolled in weekend psychology courses were investigated. The results showed that leader-member exchange mediated the effects of role stressors on job satisfaction and turnover intention. Implications of these results are discussed and directions for future research are suggested.

  20. Stressors, stress and stress consequences during long-duration manned space missions: a descriptive model

    Science.gov (United States)

    Geuna, Stefano; Brunelli, Francesco; Perino, Maria A.

    Keeping crew members in good health is a major factor in the success or failure of long-duration manned space missions. Among the many possible agents that can affect the crew's general well-being, stress is certainly one of the most critical because of its implications on human health and performance, both physical and mental. Nevertheless, very few studies have been performed on this fundamental issue and none of them has addressed it in its entirity, considering its diverse physical and psychological aspects. In this work, a descriptive model is proposed to expound the mechanism and sequence of events which mediate stress. A critical analysis of the information provided by past manned spaceflights and by dedicated research performed in analogous environments is presented, and an extrapolation of the available data on human stress in such extreme conditions is proposed. Both internal and external stressors have been identified, at physical and psychosocial levels, thus providing the basis for their early detection and preventive reduction. The possible negative consequences of stress that may lead to disease in crewmembers are described. Finally, the most effective instruments which may be of help in reducing space-related human stress and treating its negative consequences are suggested.

  1. Studying historical occupational careers with multilevel growth models

    Directory of Open Access Journals (Sweden)

    Wiebke Schulz

    2010-10-01

    Full Text Available In this article we propose to study occupational careers with historical data by using multilevel growth models. Historical career data are often characterized by a lack of information on the timing of occupational changes and by different numbers of observations of occupations per individual. Growth models can handle these specificities, whereas standard methods, such as event history analyses can't. We illustrate the use of growth models by studying career success of men and women, using data from the Historical Sample of the Netherlands. The results show that the method is applicable to male careers, but causes trouble when analyzing female careers.

  2. The contribution of gender-role orientation, work factors and home stressors to psychological well-being and sickness absence in male- and female-dominated occupational groups.

    Science.gov (United States)

    Evans, Olga; Steptoe, Andrew

    2002-02-01

    The associations of work stress, types of work and gender-role orientation with psychological well-being and sickness absence were investigated in a questionnaire survey of 588 male and female nurses and 387 male and female accountants. We hypothesised that health might be impaired among women working in the male-dominated occupation (accountancy), and men in the female-dominated occupation (nursing), but that effects might be moderated by job strain (perceptions of high demand and low control), work and home hassles, and traditional male (instrumentality) and female (expressivity) psychological characteristics. Responses were analysed from 172 female and 61 male nurses, and from 53 female and 81 male commercial accountants. Female accountants were more likely than other groups to have high anxiety scores on the Hospital Anxiety and Depression Scales, while male nurses had the highest rates of sickness absence. Male nurses and female accountants also reported more work-related hassles than did female nurses and male accountants. Men and women in the same occupation did not differ in job strain or job social support, but nurses reported greater job strain than accountants, due to higher ratings of demands and lower skill utilisation. After adjusting for age, sex, occupation, paid work hours and a measure of social desirability bias, risk of elevated anxiety was independently associated with higher job strain, lower job social support, more work hassles, more domestic responsibility, lower instrumentality and higher expressivity. The association between sex and anxiety was no longer significant after instrumentality had been entered into the regression model. Sickness absence of more than three days over the past 12 months was independently associated with higher job strain, more work hassles, lower instrumentality and higher expressivity. The results suggest that when men and women occupy jobs in which they are in the cultural and numerical minority, there may be

  3. Dynamic occupational risk model for offshore operations in harsh environments

    International Nuclear Information System (INIS)

    Song, Guozheng; Khan, Faisal; Wang, Hangzhou; Leighton, Shelly; Yuan, Zhi; Liu, Hanwen

    2016-01-01

    The expansion of offshore oil exploitation into remote areas (e.g., Arctic) with harsh environments has significantly increased occupational risks. Among occupational accidents, slips, trips and falls from height (STFs) account for a significant portion. Thus, a dynamic risk assessment of the three main occupational accidents is meaningful to decrease offshore occupational risks. Bow-tie Models (BTs) were established in this study for the risk analysis of STFs considering extreme environmental factors. To relax the limitations of BTs, Bayesian networks (BNs) were developed based on BTs to dynamically assess risks of STFs. The occurrence and consequence probabilities of STFs were respectively calculated using BTs and BNs, and the obtained probabilities verified BNs' rationality and advantage. Furthermore, the probability adaptation for STFs was accomplished in a specific scenario with BNs. Finally, posterior probabilities of basic events were achieved through diagnostic analysis, and critical basic events were analyzed based on their posterior likelihood to cause occupational accidents. The highlight is systematically analyzing STF accidents for offshore operations and dynamically assessing their risks considering the harsh environmental factors. This study can guide the allocation of prevention resources and benefit the safety management of offshore operations. - Highlights: • A novel dynamic risk model for occupational accidents. • First time consideration of harsh environment in occupational accident modeling. • A Bayesian network based model for risk management strategies.

  4. The EBD Teacher Stressors Questionnaire.

    Science.gov (United States)

    Center, David B.; Steventon, Candace

    2001-01-01

    Two studies examined the validity of a self-report instrument that assesses occupational stressors in teachers of students with emotional and behavioral disorders (EBD). Differences were found in the stress management resources of low and high scoring EBD teachers on the measure and between scores of EBD and general education teachers, although…

  5. Dual Diathesis-Stressor Model of Emotional and Linguistic Contributions to Developmental Stuttering

    Science.gov (United States)

    Walden, Tedra A.; Frankel, Carl B.; Buhr, Anthony P.; Johnson, Kia N.; Conture, Edward G.; Karrass, Jan M.

    2012-01-01

    This study assessed emotional and speech-language contributions to childhood stuttering. A dual diathesis-stressor framework guided this study, in which both linguistic requirements and skills, and emotion and its regulation, are hypothesized to contribute to stuttering. The language diathesis consists of expressive and receptive language skills.…

  6. Predicting carnivore occurrence with noninvasive surveys and occupancy modeling

    Science.gov (United States)

    Long, Robert A.; Donovan, Therese M.; MacKay, Paula; Zielinski, William J.; Buzas, Jeffrey S.

    2011-01-01

    Terrestrial carnivores typically have large home ranges and exist at low population densities, thus presenting challenges to wildlife researchers. We employed multiple, noninvasive survey methods—scat detection dogs, remote cameras, and hair snares—to collect detection–nondetection data for elusive American black bears (Ursus americanus), fishers (Martes pennanti), and bobcats (Lynx rufus) throughout the rugged Vermont landscape. We analyzed these data using occupancy modeling that explicitly incorporated detectability as well as habitat and landscape variables. For black bears, percentage of forested land within 5 km of survey sites was an important positive predictor of occupancy, and percentage of human developed land within 5 km was a negative predictor. Although the relationship was less clear for bobcats, occupancy appeared positively related to the percentage of both mixed forest and forested wetland habitat within 1 km of survey sites. The relationship between specific covariates and fisher occupancy was unclear, with no specific habitat or landscape variables directly related to occupancy. For all species, we used model averaging to predict occurrence across the study area. Receiver operating characteristic (ROC) analyses of our black bear and fisher models suggested that occupancy modeling efforts with data from noninvasive surveys could be useful for carnivore conservation and management, as they provide insights into habitat use at the regional and landscape scale without requiring capture or direct observation of study species.

  7. Modelling diversity in building occupant behaviour: a novel statistical approach

    DEFF Research Database (Denmark)

    Haldi, Frédéric; Calì, Davide; Andersen, Rune Korsholm

    2016-01-01

    We propose an advanced modelling framework to predict the scope and effects of behavioural diversity regarding building occupant actions on window openings, shading devices and lighting. We develop a statistical approach based on generalised linear mixed models to account for the longitudinal nat...

  8. [Application of occupational hazard risk index model in occupational health risk assessment in a decorative coating manufacturing enterprises].

    Science.gov (United States)

    He, P L; Zhao, C X; Dong, Q Y; Hao, S B; Xu, P; Zhang, J; Li, J G

    2018-01-20

    Objective: To evaluate the occupational health risk of decorative coating manufacturing enterprises and to explore the applicability of occupational hazard risk index model in the health risk assessment, so as to provide basis for the health management of enterprises. Methods: A decorative coating manufacturing enterprise in Hebei Province was chosen as research object, following the types of occupational hazards and contact patterns, the occupational hazard risk index model was used to evaluate occupational health risk factors of occupational hazards in the key positions of the decorative coating manufacturing enterprise, and measured with workplace test results and occupational health examination. Results: The positions of oily painters, water-borne painters, filling workers and packers who contacted noise were moderate harm. And positions of color workers who contacted chromic acid salts, oily painters who contacted butyl acetate were mild harm. Other positions were harmless. The abnormal rate of contacting noise in physical examination results was 6.25%, and the abnormality was not checked by other risk factors. Conclusion: The occupational hazard risk index model can be used in the occupational health risk assessment of decorative coating manufacturing enterprises, and noise was the key harzard among occupational harzards in this enterprise.

  9. A Linear Mixed-Effects Model of Wireless Spectrum Occupancy

    Directory of Open Access Journals (Sweden)

    Pagadarai Srikanth

    2010-01-01

    Full Text Available We provide regression analysis-based statistical models to explain the usage of wireless spectrum across four mid-size US cities in four frequency bands. Specifically, the variations in spectrum occupancy across space, time, and frequency are investigated and compared between different sites within the city as well as with other cities. By applying the mixed-effects models, several conclusions are drawn that give the occupancy percentage and the ON time duration of the licensed signal transmission as a function of several predictor variables.

  10. Modeling Single Occupant Vehicle Behavior in High-Occupancy Toll (HOT) Facilities

    Science.gov (United States)

    2009-12-14

    High-occupancy toll (HOT) lanes are in operation, under construction, and planned for in several major metropolitan areas. The premise behind HOT lanes is to allow single occupant vehicles (SOVs) to access high occupancy vehicle (HOV) lanes (and theo...

  11. Managing diverse occupational therapy resources in a creative, corporate model.

    Science.gov (United States)

    Baptiste, S

    1993-10-01

    Two occupational therapy departments were amalgamated into a corporate whole and charged with the development of a workable, corporate structure. The departmental model which was developed served to enhance the concepts of quality of working life, employee autonomy, management team and quality circle theory. This paper provides a background from business and organizational literature, and outlines the development of the departmental model, in concert with the adoption of the client-centred model of occupational performance as a department basis for practice. This development was taking place concurrently with larger, institutional changes into a decentralized clinical programme management model. Discussion highlights the level of staff satisfaction with the changes, areas of concern during the development of the system and plans for the future growth. During this period of massive and critical change in the delivery of health care services, there has been a trend in restructuring health care institutions towards decentralized models. This paper will describe the experience of one occupational therapy department in developing an innovative departmental structure involving participatory management amalgamation. It is believed that the experience of the past occupational therapy work units with one viable option for a renewed management model. Staff skill sets can be maximized and optimal potential realized while faced with inevitable resource shrinkage and service reorganization.

  12. An Integrated Modeling Framework Forecasting Ecosystem Exposure-- A Systems Approach to the Cumulative Impacts of Multiple Stressors

    Science.gov (United States)

    Johnston, J. M.

    2013-12-01

    Freshwater habitats provide fishable, swimmable and drinkable resources and are a nexus of geophysical and biological processes. These processes in turn influence the persistence and sustainability of populations, communities and ecosystems. Climate change and landuse change encompass numerous stressors of potential exposure, including the introduction of toxic contaminants, invasive species, and disease in addition to physical drivers such as temperature and hydrologic regime. A systems approach that includes the scientific and technologic basis of assessing the health of ecosystems is needed to effectively protect human health and the environment. The Integrated Environmental Modeling Framework 'iemWatersheds' has been developed as a consistent and coherent means of forecasting the cumulative impact of co-occurring stressors. The Framework consists of three facilitating technologies: Data for Environmental Modeling (D4EM) that automates the collection and standardization of input data; the Framework for Risk Assessment of Multimedia Environmental Systems (FRAMES) that manages the flow of information between linked models; and the Supercomputer for Model Uncertainty and Sensitivity Evaluation (SuperMUSE) that provides post-processing and analysis of model outputs, including uncertainty and sensitivity analysis. Five models are linked within the Framework to provide multimedia simulation capabilities for hydrology and water quality processes: the Soil Water Assessment Tool (SWAT) predicts surface water and sediment runoff and associated contaminants; the Watershed Mercury Model (WMM) predicts mercury runoff and loading to streams; the Water quality Analysis and Simulation Program (WASP) predicts water quality within the stream channel; the Habitat Suitability Index (HSI) model scores physicochemical habitat quality for individual fish species; and the Bioaccumulation and Aquatic System Simulator (BASS) predicts fish growth, population dynamics and bioaccumulation

  13. Advanced REACH tool: A Bayesian model for occupational exposure assessment

    NARCIS (Netherlands)

    McNally, K.; Warren, N.; Fransman, W.; Entink, R.K.; Schinkel, J.; Van Tongeren, M.; Cherrie, J.W.; Kromhout, H.; Schneider, T.; Tielemans, E.

    2014-01-01

    This paper describes a Bayesian model for the assessment of inhalation exposures in an occupational setting; the methodology underpins a freely available web-based application for exposure assessment, the Advanced REACH Tool (ART). The ART is a higher tier exposure tool that combines disparate

  14. Management decision making for fisher populations informed by occupancy modeling

    Science.gov (United States)

    Fuller, Angela K.; Linden, Daniel W.; Royle, J. Andrew

    2016-01-01

    Harvest data are often used by wildlife managers when setting harvest regulations for species because the data are regularly collected and do not require implementation of logistically and financially challenging studies to obtain the data. However, when harvest data are not available because an area had not previously supported a harvest season, alternative approaches are required to help inform management decision making. When distribution or density data are required across large areas, occupancy modeling is a useful approach, and under certain conditions, can be used as a surrogate for density. We collaborated with the New York State Department of Environmental Conservation (NYSDEC) to conduct a camera trapping study across a 70,096-km2 region of southern New York in areas that were currently open to fisher (Pekania [Martes] pennanti) harvest and those that had been closed to harvest for approximately 65 years. We used detection–nondetection data at 826 sites to model occupancy as a function of site-level landscape characteristics while accounting for sampling variation. Fisher occupancy was influenced positively by the proportion of conifer and mixed-wood forest within a 15-km2 grid cell and negatively associated with road density and the proportion of agriculture. Model-averaged predictions indicated high occupancy probabilities (>0.90) when road densities were low (0.50). Predicted occupancy ranged 0.41–0.67 in wildlife management units (WMUs) currently open to trapping, which could be used to guide a minimum occupancy threshold for opening new areas to trapping seasons. There were 5 WMUs that had been closed to trapping but had an average predicted occupancy of 0.52 (0.07 SE), and above the threshold of 0.41. These areas are currently under consideration by NYSDEC for opening a conservative harvest season. We demonstrate the use of occupancy modeling as an aid to management decision making when harvest-related data are unavailable and when budgetary

  15. A measurement model of perinatal stressors: identifying risk for postnatal emotional distress in mothers of high-risk infants.

    Science.gov (United States)

    DeMier, R L; Hynan, M T; Hatfield, R F; Varner, M W; Harris, H B; Manniello, R L

    2000-01-01

    A measurement model of perinatal stressors was first evaluated for reliability and then used to identify risk factors for postnatal emotional distress in high-risk mothers. In Study 1, six measures (gestational age of the baby, birthweight, length of the baby's hospitalization, a postnatal complications rating for the infant, and Apgar scores at 1 and 5 min) were obtained from chart reviews of preterm births at two different hospitals. Confirmatory factor analyses revealed that the six measures could be accounted for by three factors: (a) Infant Maturity, (b) Apgar Ratings, and (c) Complications. In Study 2, a modified measurement model indicated that Infant Maturity and Complications were significant predictors of postnatal emotional distress in an additional sample of mothers. This measurement model may also be useful in predicting (a) other measures of psychological distress in parents, and (b) measures of cognitive and motor development in infants.

  16. Neurotoxicity in Preclinical Models of Occupational Exposure to Organophosphorus Compounds

    Science.gov (United States)

    Voorhees, Jaymie R.; Rohlman, Diane S.; Lein, Pamela J.; Pieper, Andrew A.

    2017-01-01

    Organophosphorus (OPs) compounds are widely used as insecticides, plasticizers, and fuel additives. These compounds potently inhibit acetylcholinesterase (AChE), the enzyme that inactivates acetylcholine at neuronal synapses, and acute exposure to high OP levels can cause cholinergic crisis in humans and animals. Evidence further suggests that repeated exposure to lower OP levels insufficient to cause cholinergic crisis, frequently encountered in the occupational setting, also pose serious risks to people. For example, multiple epidemiological studies have identified associations between occupational OP exposure and neurodegenerative disease, psychiatric illness, and sensorimotor deficits. Rigorous scientific investigation of the basic science mechanisms underlying these epidemiological findings requires valid preclinical models in which tightly-regulated exposure paradigms can be correlated with neurotoxicity. Here, we review the experimental models of occupational OP exposure currently used in the field. We found that animal studies simulating occupational OP exposures do indeed show evidence of neurotoxicity, and that utilization of these models is helping illuminate the mechanisms underlying OP-induced neurological sequelae. Still, further work is necessary to evaluate exposure levels, protection methods, and treatment strategies, which taken together could serve to modify guidelines for improving workplace conditions globally. PMID:28149268

  17. Profissionais de saúde mental: estresse e estressores ocupacionais stress e estressores ocupacionais em saúde mental Profesionales de la salud mental: estrés y estresores ocupacionalesestrés y estresores ocupacionales en salud mental Mental health professionals: stress and occupational stressors stress and occupational stressors of mental health

    Directory of Open Access Journals (Sweden)

    Ana Flávia de Oliveira Santos

    2010-06-01

    ón en el trabajo fueron los factores más frecuentemente asociados a la percepción de estar bajo estrés. Se concluye que los profesionales vivencian estresores asociados a los cambios relativos al paradigma psicosocial de atención, apuntando a la necesidad de intervención dirigida al desarrollo de estrategias de enfrentamiento de las situaciones ocupacionales estresoras.Mental health professionals are particularly vulnerable to stress, considering the characteristics of the work they develop. The purpose of this study was to assess the manifestation of stress, self-perception of stress, and stressing work factors in substitutive mental health service professionals. Twenty-five workers, working for at least six months, took part in the study. The instruments employed were Lipp's Inventory of Stress Symptoms in Adults and a Complementary Script. Quantitative data were treated by descriptive statistics, and the remaining data were analyzed qualitatively. It was observed that 36.0% of the professional had stress manifestations, and 44.0% perceived they were under stress. Work conditions and relationships at work were the most frequent factors associated to the perception of being under stress. In conclusion, professionals experience stressors associated with the changes implied in the psychosocial paradigm of care. Thus, there is a need to make direct interventions toward the development of coping strategies in stressing occupational situations.

  18. International survey on current occupant modelling approaches in building performance simulation

    NARCIS (Netherlands)

    O'Brien, W.; Gaetani, I.; Gilani, S.; Carlucci, S.; Hoes, P.; Hensen, J.L.M.

    2017-01-01

    It is not evident that practitioners have kept pace with latest research developments in building occupant behaviour modelling; nor are the attitudes of practitioners regarding occupant behaviour modelling well understood. In order to guide research and development efforts, researchers,

  19. Does aging make employees more resilient to job stress? Age as a moderator in the job stressor-well-being relationship in three Finnish occupational samples.

    Science.gov (United States)

    Mauno, Saija; Ruokolainen, Mervi; Kinnunen, Ulla

    2013-01-01

    This study examined whether an employee's age moderates the relationships between job stressors (i.e. job insecurity, workload, work-family conflict) and self-rated well-being (i.e. work-family enrichment, life satisfaction, job satisfaction, vigor at work). Analysis of covariance and moderated hierarchical regression analysis were used to examine the cross-sectional Finnish data collected among service sector employees (N = 1037), nurses (N = 1719), and academic employees (N = 945). In a situation of high job insecurity, the younger nurses reported higher work-family enrichment, job satisfaction, and vigor compared to their older colleagues. A similar result was also found among the service sector workers in relation to vigor at work. Thus, young age buffered against negative outcomes related to job insecurity. Moreover, older age buffered against the negative effect of high workload on job satisfaction among the service sector and against high work-family conflict on life satisfaction among the academic employees. More attention should be paid to the ability of younger employees to manage problems related to work-family imbalance and high workload, and to older employees' ability to cope with job insecurity. The findings of this study recommend different stress management interventions for older and younger employees.

  20. Work stressors, sleep quality, and alcohol-related problems across deployment: A parallel process latent growth modeling approach among Navy members.

    Science.gov (United States)

    Bravo, Adrian J; Kelley, Michelle L; Hollis, Brittany F

    2017-10-01

    This study examined how work stressors were associated with sleep quality and alcohol-related problems among U.S. Navy members over the course of deployment. Participants were 101 U.S. Navy members assigned to an Arleigh Burke-class destroyer who experienced an 8-month deployment after Operational Enduring Freedom/Operation Iraqi Freedom. Approximately 6 weeks prior to deployment, 6 weeks after deployment, and 6 months reintegration, participants completed measures that assessed work stressors, sleep quality, and alcohol-related problems. A piecewise latent growth model was conducted in which the structural paths assessed if work stressors influenced sleep quality or its growth over time, and in turn if sleep quality influenced alcohol-related problems intercepts or growth over time. A significant indirect effect was found such that increases in work stressors from pre- to postdeployment predicted decreases in sleep quality, which in turn were associated with increases in alcohol-related problems from pre- to postdeployment. These effects were maintained from postdeployment through the 6-month reintegration. Findings suggest that work stressors may have important implications for sleep quality and alcohol-related problems. Positive methods of addressing stress and techniques to improve sleep quality are needed as both may be associated with alcohol-related problems among current Navy members. Copyright © 2016 John Wiley & Sons, Ltd.

  1. Mussel dynamics model: A hydroinformatics tool for analyzing the effects of different stressors on the dynamics of freshwater mussel communities

    Science.gov (United States)

    Morales, Y.; Weber, L.J.; Mynett, A.E.; Newton, T.J.

    2006-01-01

    A model for simulating freshwater mussel population dynamics is presented. The model is a hydroinformatics tool that integrates principles from ecology, river hydraulics, fluid mechanics and sediment transport, and applies the individual-based modelling approach for simulating population dynamics. The general model layout, data requirements, and steps of the simulation process are discussed. As an illustration, simulation results from an application in a 10 km reach of the Upper Mississippi River are presented. The model was used to investigate the spatial distribution of mussels and the effects of food competition in native unionid mussel communities, and communities infested by Dreissena polymorpha, the zebra mussel. Simulation results were found to be realistic and coincided with data obtained from the literature. These results indicate that the model can be a useful tool for assessing the potential effects of different stressors on long-term population dynamics, and consequently, may improve the current understanding of cause and effect relationships in freshwater mussel communities. ?? 2006 Elsevier B.V. All rights reserved.

  2. Combined chemical (fluoranthene) and drought effects on Lumbricus rubellus demonstrate the applicability of the independent action model for multiple stressor assessment.

    Science.gov (United States)

    Long, Sara M; Reichenberg, Fredrik; Lister, Lindsay J; Hankard, Peter K; Townsend, Joanna; Mayer, Philipp; Wright, Julian; Holmstrup, Martin; Svendsen, Claus; Spurgeon, David J

    2009-03-01

    The combined effect of a chemical (fluoranthene) and a nonchemical stress (reduced soil moisture content) to the widely distributed earthworm Lumbricus rubellus were investigated in a laboratory study. Neither fluoranthene (up to 500 microg/g) nor low soil moisture (15% below optimal) had a significant effect on the survival of the exposed worms, but a significant effect on reproduction (cocoon production rate) was found for both stressors (p IA) model that is widely used in pharmacology and chemical mixture risk assessment. Fitting of the IA model provided a good description of the combined stressor data (accounting for 53.7% of total variation) and was the most parsimonious model describing joint effect (i.e., the description of the data was not improved by addition of further parameters accounting for synergism or antagonism). Thus, the independent action of the two responses was further supported by measurement of internal fluoranthene exposure. The chemical activity of fluoranthene in worm tissue was correlated only with soil fluoranthene concentration and not with soil moisture content. Taken together these results suggest that the IA model can help interpret the joint effects of chemical and nonchemical stressors. Such analyses should, however, be done with caution since the literature data set suggests that there may be cases where interactions between stressors result in joint effects that differ significantly from IA predictions.

  3. Workplace and security stressors and mental health among migrant workers on the Thailand-Myanmar border.

    Science.gov (United States)

    Meyer, Sarah R; Decker, Michele R; Tol, Wietse A; Abshir, Nada; Mar, Aye Aye; Robinson, W Courtland

    2016-05-01

    Migrant workers in low-resource settings may experience multiple types of workplace and security-related stressors. This study explores the relationship between these stressors and adverse mental health outcomes, through a study of migrant workers from Myanmar, working in agriculture, factory, and sex industries in and around Mae Sot, Thailand. Respondent-driven sampling was used to recruit a total sample of 589 male and female migrants. Trained data collectors administered a survey, which included measures of workplace and security-related stressors, and depression and anxiety symptoms. Multivariate regression models were conducted separately for depression and anxiety symptoms. For male agricultural workers, security stressors (β = 1.9, p = .001) are associated with an increase in depression symptoms and coercive working conditions are associated with an increase in anxiety symptoms (β = .8, p = .000). For female agricultural workers, daily hassles and stressors were associated with both depression (β = 1.5, p = .000) and anxiety (β = .5, p = .027), and barriers to exit (β = 3.0, p = .005) and security stressors (β = .9, p = .010) were significantly associated with increased depression symptoms. In the factory subsample, sexual assault and abuse (depression: β = 2.7, p = .009; anxiety: β = 2.8, p = .002) and daily hassles and stressors (depression: β = .7, p = .007; anxiety: β = .7, p = .001) were both significantly associated with increased depression and anxiety symptoms for males. Other categories of stressors similarly showed different associations with mental health outcomes between occupational groups, and between male and female migrant workers. The differing influences of stressors on mental health between the three occupational groups, and between males and females, indicate the need for targeted and tailored approaches to reduce specific stressors and improve services to address mental health needs

  4. Identification of psychobiological stressors among HIV-positive women. HIV Neurobehavioral Research Center (HNRC) Group.

    Science.gov (United States)

    Semple, S J; Patterson, T L; Temoshok, L R; McCutchan, J A; Straits-Tröster, K A; Chandler, J L; Grant, I

    1993-01-01

    This research describes major stressors in the lives of women who have been infected with the human immunodeficiency virus (HIV). Thirty-one HIV antibody positive (HIV+) women infected primarily through heterosexual contact participated in a two hour semi-structured interview detailing the circumstances, context, and consequences of all stressful life events and difficulties experienced within the preceding six months. Qualitative methods of data analyses were utilized (Miles & Huberman, 1984). HIV-related life events and difficulties were classified into primary and secondary stressors based on the stress process model (Pearlin et al., 1981). Problems arising directly from one's seropositivity were defined as primary stressors. Stressful life events and difficulties occurring in other role areas were defined as secondary stressors. Six categories of HIV-related stressors were identified and quantified. Primary stressors were health-related, and included both gynecological problems (e.g., amenorrhea) and general symptoms of HIV infection (e.g., fatigue). Secondary stressors related to child and family (e.g., future guardianship of children), marital/partner relations (e.g., disclosure of HIV+ status), occupation (e.g., arranging time-off for medical appointments), economic problems (e.g., insurance "hassles"), and social network events (e.g., death of friends from AIDS). This research indicates that HIV-positive women are exposed to multiple stressors; some may be viewed as unique to women, whereas others may be considered common to both sexes. Identification of stressors has implications for the design of medical and psychiatric interventions for women.

  5. Occupant behavior in building energy simulation: towards a fit-for-purpose modeling strategy

    NARCIS (Netherlands)

    Gaetani, I.; Hoes, P.; Hensen, J.L.M.

    2016-01-01

    Occupant behavior is nowadays acknowledged as a main source of discrepancy between predicted and actual building performance; therefore, researchers attempt to model occupants' presence and adaptive actions more realistically. Literature shows a proliferation of increasingly complex, data-based

  6. An integrated occupational hygiene consultation model for the catering industry.

    Science.gov (United States)

    Lin, Yi-Kuei; Lee, Lien-Hsiung

    2010-07-01

    Vegetable oil used in food processing, during high-temperature exposure, will generate particulate matter (PM) and polycyclic aromatic hydrocarbons (PAHs), which are carcinogenic chemical compounds, with the potential to cause lung disease for restaurant kitchen staff. This study's design includes a three-stage consultation process with eight major consultation items, in order to build an integrated consultation model for occupational hygiene. This model combines inspection and consultation, targeting Chinese restaurants in the catering industry. Characteristics of the integrated consultation model include cooperation between different government departments and collaboration with nongovernmental, professional consulting organizations. An additional benefit of the model is the building of a good partnership relationship with the Catering Trade Association. The consultation model helps Chinese restaurants attain improvements in their work environments with minimal investment. Postconsultation, results show a 63.35% and 61.98% (P < 0.001) decrease in the mean time-weighted concentration of exposure to PM and PAHs, respectively. The overall regulation compliance rate of Chinese restaurants significantly increased from 34.3% to 89.6%. These results show that the integrated consultation model for occupational hygiene not only helps small and medium enterprises reduce exposure concentrations in the workplace but also has specific potential for successful implementation in Taiwan.

  7. Agreeableness, Extraversion, Stressor and Physiological Stress Response

    OpenAIRE

    Xiaoyuan Chu; Zhentao Ma; Yuan Li; Jing Han

    2015-01-01

    Based on the theoretical analysis, with first-hand data collection and using multiple regression models, this study explored the relationship between agreeableness, extraversion, stressor and stress response and figured out interactive effect of agreeableness, extraversion, and stressor on stress response. We draw on the following conclusions: (1) the interaction term of stressor (work) and agreeableness can negatively predict physiological stress response; (2) the interaction term of stresso...

  8. Occupational therapy influence on a carer peer support model in a clinical mental health service.

    Science.gov (United States)

    Bourke, Cate; Sanders, Bronwyn; Allchin, Becca; Lentin, Primrose; Lang, Shannon

    2015-10-01

    Current policy frameworks call for the participation of consumers and carers in all levels of mental health service delivery in Australia. Such inclusion leads to better outcomes for all, however, it is recognised that carers have needs and occupations beyond their carer role. The aim of this article is to describe an innovative carer peer support program developed by a group of occupational therapists. The article describes the rationale, phases of development and the role that occupational therapists played in developing and sustaining the model. This is followed by an exploration of the occupational therapy attitudes, knowledge and skills that contributed to the conceptualisation and implementation of the model. Five occupational therapists engaged in a review process involving documentation, literature review, evaluation, reflection and discussion. Four of the occupational therapists had either coordinated or managed the service described. The fifth author facilitated the process. Review of the model indicates it equips carers to perform their caring occupation and helps carers recognise the need for occupations beyond caring, for their health and wellbeing. Employing carers as paid workers values their 'real life' experience in their caring occupation. Findings also illustrate that the attitudes, knowledge, skills and competency standards of occupational therapists are well suited in enabling this emerging area of service delivery. Although this model has been developed in a clinical mental health setting, the key principles could be applied with carers or consumers across a variety of settings in which occupational therapists are employed. © 2015 Occupational Therapy Australia.

  9. Applying a realistic evaluation model to occupational safety interventions

    DEFF Research Database (Denmark)

    Pedersen, Louise Møller

    2018-01-01

    Background: Recent literature characterizes occupational safety interventions as complex social activities, applied in complex and dynamic social systems. Hence, the actual outcomes of an intervention will vary, depending on the intervention, the implementation process, context, personal characte......Background: Recent literature characterizes occupational safety interventions as complex social activities, applied in complex and dynamic social systems. Hence, the actual outcomes of an intervention will vary, depending on the intervention, the implementation process, context, personal...... and qualitative methods. This revised model has, however, not been applied in a real life context. Method: The model is applied in a controlled, four-component, integrated behaviour-based and safety culture-based safety intervention study (2008-2010) in a medium-sized wood manufacturing company. The interventions...... involve the company’s safety committee, safety manager, safety groups and 130 workers. Results: The model provides a framework for more valid evidence of what works within injury prevention. Affective commitment and role behaviour among key actors are identified as crucial for the implementation...

  10. A new contribution to the classification of stressors affecting nursing professionals

    Directory of Open Access Journals (Sweden)

    Jesús Cremades Puerto

    Full Text Available Objective: to identify and classify the most important occupational stressors affecting nursing professionals in the medical units within a hospital. Method: quantitative-qualitative, descriptive and prospective study performed with Delphi technique in the medical units of a general university hospital, with a sample of 30 nursing professionals. Results: the stressors were work overload, frequent interruptions in the accomplishment of their tasks, night working, simultaneity of performing different tasks, not having enough time to give emotional support to the patient or lack of time for some patients who need it, among others. Conclusion: the most consensual stressors were ranked as work overload, frequent interruptions in the accomplishment of their tasks, night working and, finally, simultaneity of performing different tasks. These results can be used as a tool in the clinical management of hospital units, aiming to improve the quality of life of nursing professionals, organizational models and, in addition, continuous improvement in clinical treatment.

  11. A conceptual model for the analysis of multi-stressors in linked groundwater-surface water systems.

    Science.gov (United States)

    Kaandorp, Vince P; Molina-Navarro, Eugenio; Andersen, Hans E; Bloomfield, John P; Kuijper, Martina J M; de Louw, Perry G B

    2018-06-15

    Groundwater and surface water are often closely coupled and are both under the influence of multiple stressors. Stressed groundwater systems may lead to a poor ecological status of surface waters but to date no conceptual framework to analyse linked multi-stressed groundwater - surface water systems has been developed. In this paper, a framework is proposed showing the effect of groundwater on surface waters in multiple stressed systems. This framework will be illustrated by applying it to four European catchments, the Odense, Denmark, the Regge and Dinkel, Netherlands, and the Thames, UK, and by assessing its utility in analysing the propagation or buffering of multi-stressors through groundwater to surface waters in these catchments. It is shown that groundwater affects surface water flow, nutrients and temperature, and can both propagate stressors towards surface waters and buffer the effect of stressors in space and time. The effect of groundwater on drivers and states depends on catchment characteristics, stressor combinations, scale and management practises. The proposed framework shows how groundwater in lowland catchments acts as a bridge between stressors and their effects within surface waters. It shows water managers how their management areas might be influenced by groundwater, and helps them to include this important, but often overlooked part of the water cycle in their basin management plans. The analysis of the study catchments also revealed a lack of data on the temperature of both groundwater and surface water, while it is an important parameter considering future climate warming. Copyright © 2018. Published by Elsevier B.V.

  12. Leadership and Occupational Stress

    Science.gov (United States)

    Stickle, Fred E.; Scott, Kelly

    2016-01-01

    In a leadership position, it is important to understand what stress is and how it affects others. In an occupational setting, stressors vary according to personality types, gender, and occupational rank. The purpose of this manuscript is to review the foundations of stress and to explore how personality characteristics influence stress.…

  13. Ecological Models to Predict and Test the Effects of Chemical Stressors: Integration across 2 EPA STAR cooperative agreements

    Science.gov (United States)

    Accessible tools to quantify adverse outcomes pathways (AOPs) that can predict the ecological effects of chemicals and other stressors are a major goal of Chemical Safety and Sustainability research within US EPA’s Office of Research and Development. To address this goal, w...

  14. Eco-SpaCE: An object-oriented, spatially explicit model to assess the risk of multiple environmental stressors on terrestrial vertebrate populations

    International Nuclear Information System (INIS)

    Loos, Mark; Ragas, Ad M.J.; Plasmeijer, Rinus; Schipper, Aafke M.; Hendriks, A. Jan

    2010-01-01

    Wildlife organisms are exposed to a combination of chemical, biological and physical stressors. Information about the relative impact of each stressor can support management decisions, e.g., by the allocation of resources to counteract those stressors that cause most harm. The present paper introduces Eco-SpaCE; a novel receptor-oriented cumulative exposure model for wildlife species that includes relevant ecological processes such as spatial habitat variation, food web relations, predation, and life history. A case study is presented in which the predicted mortality due to cadmium contamination is compared with the predicted mortality due to flooding, starvation, and predation for three small mammal species (Wood mouse, Common vole, and European mole) and a predator (Little owl) living in a lowland floodplain along the river Rhine in The Netherlands. Results indicated that cadmium is the principal stressor for European mole and Little owl populations. Wood mouse and Common vole population densities were mainly influenced by flooding and food availability. Their estimated population sizes were consistent with numbers reported in literature. Predictions for cadmium accumulation and flooding stress were in agreement with field data. The large uncertainty around cadmium toxicity for wildlife leads to the conclusion that more species-specific ecotoxicological data is required for more realistic risk assessments. The predictions for starvation were subject to the limited quantitative information on biomass obtainable as food for vertebrates. It is concluded that the modelling approach employed in Eco-SpaCE, combining ecology with ecotoxicology, provides a viable option to explore the relative contribution of contamination to the overall stress in an ecosystem. This can help environmental managers to prioritize management options, and to reduce local risks.

  15. At the heart of the Nordic occupational welfare model

    DEFF Research Database (Denmark)

    Greve, Bent

    2018-01-01

    Sweden and Denmark are countries with a strong tradition of the involvement of labor market partners in welfare policies, and this begs the question whether this influences the development of occupational welfare. This article depicts the reasons for, and the development of, occupational welfare,...

  16. Dynamic N -occupancy models: estimating demographic rates and local abundance from detection-nondetection data

    Science.gov (United States)

    Sam Rossman; Charles B. Yackulic; Sarah P. Saunders; Janice Reid; Ray Davis; Elise F. Zipkin

    2016-01-01

    Occupancy modeling is a widely used analytical technique for assessing species distributions and range dynamics. However, occupancy analyses frequently ignore variation in abundance of occupied sites, even though site abundances affect many of the parameters being estimated (e.g., extinction, colonization, detection probability). We introduce a new model (“dynamic

  17. Super heroes and lucky duckies: Racialized stressors among teachers.

    Science.gov (United States)

    Rauscher, Lauren; Wilson, Bianca D M

    2017-04-01

    This article explores the complex relationships between race and occupational stressors among an ethnically diverse sample of high school teachers and their implications for women's mental health. Interviews with Black, White, and Mexican American teachers suggest that workplaces are organized by subtle forms of gender and racial discrimination as well as White racial privilege; this context shapes women's experiences of occupational stressors. The data indicate that teachers experience racially specific stressors at work and make racially specific appraisals about common stressors among all teachers. Black and Mexican American women report chronic strains, such as differential workloads, perceptions of incompetence, and lack of support from administrators, whereas White teachers report, yet minimize, sexual harassment from male colleagues. Student misbehavior, a stressor shared by all teachers, is experienced and understood as a personal failing by White teachers and as a manifestation of systemic racism by teachers of color. The interviews offer important insights into the ways professional workplaces remain an arena marked by racial inequality and White privilege and that racialized stressors are differentially distributed among women. Findings support claims from intersectionality in that race, racism, and racial privilege operate in multiplicative ways that create different constellations of occupational stressors among women, which in turn have implications for wellbeing. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  18. A cohort study of psychosocial work stressors on work ability among Brazilian hospital workers.

    Science.gov (United States)

    Martinez, Maria Carmen; do Rosário Dias de Oliveira Latorre, Maria; Fischer, Frida Marina

    2015-07-01

    Hospital work is characterized by stressors that can influence work ability. The present study aims to assess the association between psychosocial work stressors and changes in work ability in a group of Brazilian hospital employees. From 1,022 workers included in a 3-year cohort started in 2009, 423 (41.4%) returned the applied questionnaires in 2012. Changes in work ability were considered as the dependent variable and the investigated psychosocial work stressors as independent variables. Logistic regression models adjusted for potential con-founders (demographic, occupational features, social support, overcommitment, and situations liable to cause pain/injury). High levels of exposure to psychosocial work stressors were significantly associated with decreased work ability: job strain (OR = 2.81), effort-reward imbalance (OR = 3.21). Strategies to reduce psychosocial work stressors should be considered to maintain hospital employees' work ability. Such strategies have implications for institutional and social policies and might be included in quality management programs. © 2015 Wiley Periodicals, Inc.

  19. A Review on Pharmacokinetic Modeling and the Effects of Environmental Stressors on Pharmacokinetics for Operational Medicine: Operational Pharmacokinetics

    Science.gov (United States)

    2009-09-01

    Manning et al. 1986), which may cause physiological changes. For example, emotional distress may lead to elevated heart rate, blood pressure and...related changes in renal functions were reported during a Stroop word color conflict test (Fauvel, Hadj-Aissa et al. 1991). Emotional stressors could...M. Skee, et al. (2001). "Pharmacokinetics of norelgestromin and ethinyl estradiol delivered by a contraceptive patch (Ortho Evra (TM)/Evra (TM

  20. Stochastic Modeling of Overtime Occupancy and Its Application in Building Energy Simulation and Calibration

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Kaiyu; Yan, Da; Hong, Tianzhen; Guo, Siyue

    2014-02-28

    Overtime is a common phenomenon around the world. Overtime drives both internal heat gains from occupants, lighting and plug-loads, and HVAC operation during overtime periods. Overtime leads to longer occupancy hours and extended operation of building services systems beyond normal working hours, thus overtime impacts total building energy use. Current literature lacks methods to model overtime occupancy because overtime is stochastic in nature and varies by individual occupants and by time. To address this gap in the literature, this study aims to develop a new stochastic model based on the statistical analysis of measured overtime occupancy data from an office building. A binomial distribution is used to represent the total number of occupants working overtime, while an exponential distribution is used to represent the duration of overtime periods. The overtime model is used to generate overtime occupancy schedules as an input to the energy model of a second office building. The measured and simulated cooling energy use during the overtime period is compared in order to validate the overtime model. A hybrid approach to energy model calibration is proposed and tested, which combines ASHRAE Guideline 14 for the calibration of the energy model during normal working hours, and a proposed KS test for the calibration of the energy model during overtime. The developed stochastic overtime model and the hybrid calibration approach can be used in building energy simulations to improve the accuracy of results, and better understand the characteristics of overtime in office buildings.

  1. Trends in measurement models and methods in understanding occupational health psychology.

    Science.gov (United States)

    Tetrick, Lois E

    2017-07-01

    Measurement of occupational health psychology constructs is the cornerstone to developing our understanding of occupational health and safety. It also is critical in the design, evaluation, and implementation of interventions to improve employees and organizations well-being. The purpose of this article is a brief review of the current state of measurement theory and practice in occupational health psychology. Also included are a discussion of development of newer measurement models and methods, which are in use in other disciplines of psychology, but have not been incorporated into the occupational health psychology. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  2. Translational PKPD modeling in schizophrenia: linking receptor occupancy of antipsychotics to efficacy and safety

    NARCIS (Netherlands)

    Pilla Reddy, Venkatesh; Kozielska, Magdalena; Johnson, Martin; Vermeulen, An; Liu, Jing; de Greef, Rik; Groothuis, Genoveva; Danhof, Meindert; Proost, Johannes

    2012-01-01

    Objectives: To link the brain dopamine D2 receptor occupancy (D2RO) of antipsychotic drugs with clinical endpoints of efficacy and safety to assess the therapeutic window of D2RO. Methods: Pharmacokinetic-Pharmacodynamic (PK-PD) models were developed to predict the D2 receptor occupancy of

  3. Occupational Decision-Related Processes for Amotivated Adolescents: Confirmation of a Model

    Science.gov (United States)

    Jung, Jae Yup; McCormick, John

    2011-01-01

    This study developed and (statistically) confirmed a new model of the occupational decision-related processes of adolescents, in terms of the extent to which they may be amotivated about choosing a future occupation. A theoretical framework guided the study. A questionnaire that had previously been administered to an Australian adolescent sample…

  4. Developing probabilistic models to predict amphibian site occupancy in a patchy landscape

    Science.gov (United States)

    R. A. Knapp; K.R. Matthews; H. K. Preisler; R. Jellison

    2003-01-01

    Abstract. Human-caused fragmentation of habitats is threatening an increasing number of animal and plant species, making an understanding of the factors influencing patch occupancy ever more important. The overall goal of the current study was to develop probabilistic models of patch occupancy for the mountain yellow-legged frog (Rana muscosa). This once-common species...

  5. Use of electronic music as an occupational therapy modality in spinal cord injury rehabilitation: an occupational performance model.

    Science.gov (United States)

    Lee, B; Nantais, T

    1996-05-01

    This article describes an electronic music program that allows clients with spinal cord injury (SCI) to form musical bands and play songs while performing therapeutic exercise in an occupational therapy program. Clients create the music by activating upper extremity exercise devices that are connected to a synthesizer through a computer. The bands choose the songs they would like to play and meet twice a week for 1 hr to practice. The 8-week program often concludes with a public performance. The music program is intended to motivate client participation in physical rehabilitation while promoting self-esteem, emotional expression, and peer support. It is based on the model of occupational performance and the theory of purposeful activity. To date, 33 persons have taken part. Client, therapist, and public response has been positive because this program highlights the abilities of persons with SCI, thereby encouraging their reintegration into the community.

  6. Application of the Human Activity Assistive Technology model for occupational therapy research.

    Science.gov (United States)

    Giesbrecht, Ed

    2013-08-01

    Theoretical models provide a framework for describing practice and integrating evidence into systematic research. There are few models that relate specifically to the provision of assistive technology in occupational therapy practice. The Human Activity Assistive Technology model is an enduring example that has continued to develop by integrating a social model of disability, concepts from occupational therapy theory and principles of assistive technology adoption and abandonment. This study first describes the core concepts of the Human Activity Assistive Technology model and reviews its development over three successive published versions. A review of the research literature reflects application of the model to clinical practice, study design, outcome measure selection and interpretation of results, particularly among occupational therapists. An evaluative framework is used to critique the adequacy of the Human Activity Assistive Technology model for practice and research, exploring attributes of clarity, simplicity, generality, accessibility and importance. Finally, recommendations are proposed for continued development of the model and research applications. Most of the existing research literature employs the Human Activity Assistive Technology model for background and study design; there is emerging evidence to support the core concepts as predictive factors. Although the concepts are generally simple, clear and applicable to occupational therapy practice and research, evolving terminology and outcomes become more complex with the conflation of integrated theories. The development of the Human Activity Assistive Technology model offers enhanced access and application for occupational therapists, but poses challenges to clarity among concepts. Suggestions are made for further development and applications of the model. © 2013 Occupational Therapy Australia.

  7. A dyadic multiple mediation model of patient and spouse stressors predicting patient dietary and exercise adherence via depression symptoms and diabetes self-efficacy.

    Science.gov (United States)

    Anderson, Jared R; Novak, Joshua R; Johnson, Matthew D; Deitz, Sharon L; Walker, Ann; Wilcox, Allison; Lewis, Virginia L; Robbins, David C

    2016-12-01

    Using dyadic data from 117 married couples in which one partner was diagnosed with Type 2 diabetes, the purpose of this study was to determine whether a number of specific patient and spouse stressors (chronic life stress, diabetes-specific stress, and physical health stress in the form of the number of comorbidities) were associated with Type 2 diabetes patients' dietary and exercise adherence through two potentially modifiable patient and spouse factors-depression symptoms and diabetes self-efficacy. We found that patient and spouse stressors, particularly patient and spouse diabetes stress and the number of patient comorbidities, were related to patient dietary and exercise adherence through patient depression symptoms and both patient and spouse diabetes self-efficacy. These conclusions were strengthened by incorporating a number of relevant control variables in our models and by testing four alternative models which supported our proposed model. These results are important because they provide further evidence of the significant role spouses' play in managing diabetes and they provide diabetes educators and clinicians with specific targets for intervention programming.

  8. Hidden Markov Models for indirect classification of occupant behaviour

    DEFF Research Database (Denmark)

    Liisberg, Jon Anders Reichert; Møller, Jan Kloppenborg; Bloem, H.

    2016-01-01

    Even for similar residential buildings, a huge variability in the energy consumption can be observed. This variability is mainly due to the different behaviours of the occupants and this impacts the thermal (temperature setting, window opening, etc.) as well as the electrical (appliances, TV......, computer, etc.) consumption. It is very seldom to find direct observations of occupant presence and behaviour in residential buildings. However, given the increasing use of smart metering, the opportunity and potential for indirect observation and classification of occupants’ behaviour is possible...... sequence of states was determined (global decoding). From reconstruction of the states, dependencies like ambient air temperature were investigated. Combined with an occupant survey, this was used to classify/interpret the states as (1) absent or asleep, (2) home, medium consumption and (3) home, high...

  9. Design and optimization for the occupant restraint system of vehicle based on a single freedom model

    Science.gov (United States)

    Zhang, Junyuan; Ma, Yue; Chen, Chao; Zhang, Yan

    2013-05-01

    Throughout the vehicle crash event, the interactions between vehicle, occupant, restraint system (VOR) are complicated and highly non-linear. CAE and physical tests are the most widely used in vehicle passive safety development, but they can only be done with the detailed 3D model or physical samples. Often some design errors and imperfections are difficult to correct at that time, and a large amount of time will be needed. A restraint system concept design approach which based on single-degree-of-freedom occupant-vehicle model (SDOF) is proposed in this paper. The interactions between the restraint system parameters and the occupant responses in a crash are studied from the view of mechanics and energy. The discrete input and the iterative algorithm method are applied to the SDOF model to get the occupant responses quickly for arbitrary excitations (impact pulse) by MATLAB. By studying the relationships between the ridedown efficiency, the restraint stiffness, and the occupant response, the design principle of the restraint stiffness aiming to reduce occupant injury level during conceptual design is represented. Higher ridedown efficiency means more occupant energy absorbed by the vehicle, but the research result shows that higher ridedown efficiency does not mean lower occupant injury level. A proper restraint system design principle depends on two aspects. On one hand, the restraint system should lead to as high ridedown efficiency as possible, and at the same time, the restraint system should maximize use of the survival space to reduce the occupant deceleration level. As an example, an optimization of a passenger vehicle restraint system is designed by the concept design method above, and the final results are validated by MADYMO, which is the most widely used software in restraint system design, and the sled test. Consequently, a guideline and method for the occupant restraint system concept design is established in this paper.

  10. Statistical Analysis and Modeling of Occupancy Patterns in Open-Plan Offices using Measured Lighting-Switch Data

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Wen-Kuei; Hong, Tianzhen

    2013-01-01

    Occupancy profile is one of the driving factors behind discrepancies between the measured and simulated energy consumption of buildings. The frequencies of occupants leaving their offices and the corresponding durations of absences have significant impact on energy use and the operational controls of buildings. This study used statistical methods to analyze the occupancy status, based on measured lighting-switch data in five-minute intervals, for a total of 200 open-plan (cubicle) offices. Five typical occupancy patterns were identified based on the average daily 24-hour profiles of the presence of occupants in their cubicles. These statistical patterns were represented by a one-square curve, a one-valley curve, a two-valley curve, a variable curve, and a flat curve. The key parameters that define the occupancy model are the average occupancy profile together with probability distributions of absence duration, and the number of times an occupant is absent from the cubicle. The statistical results also reveal that the number of absence occurrences decreases as total daily presence hours decrease, and the duration of absence from the cubicle decreases as the frequency of absence increases. The developed occupancy model captures the stochastic nature of occupants moving in and out of cubicles, and can be used to generate a more realistic occupancy schedule. This is crucial for improving the evaluation of the energy saving potential of occupancy based technologies and controls using building simulations. Finally, to demonstrate the use of the occupancy model, weekday occupant schedules were generated and discussed.

  11. Timing anthropogenic stressors to mitigate their impact on marine ecosystem resilience

    OpenAIRE

    Wu, Paul Pao-Yen; Mengersen, Kerrie; McMahon, Kathryn; Kendrick, Gary A.; Chartrand, Kathryn; York, Paul H.; Rasheed, Michael A.; Caley, M. Julian

    2017-01-01

    Better mitigation of anthropogenic stressors on marine ecosystems is urgently needed to address increasing biodiversity losses worldwide. We explore opportunities for stressor mitigation using whole-of-systems modelling of ecological resilience, accounting for complex interactions between stressors, their timing and duration, background environmental conditions and biological processes. We then search for ecological windows, times when stressors minimally impact ecological resilience, defined...

  12. Confirmatory factor analysis of Post-Occupancy Evaluation Model (POEM) for sustainable neighborhood development

    Science.gov (United States)

    Yaman, R.; Thadaniti, S.; Abdullah, J.; Ahmad, N.; Ishak, N. M.

    2018-02-01

    The sustainable urban development growth in the ASEAN region has accelerated tremendously. More demand on the sustainable development has led to bigger market driven certified green neighborhood and buildings. However, there is a lack of post-occupancy evaluation study conducted in assessing the end-users perspective on the certified sustainable neighborhood development. This paper aims to investigate the end-users point of view on sustainable dimension pillar (SDP) adaptation based on environment dimension, social dimension and economic dimension using Post-Occupancy Evaluation Model (POEM) framework. The research methodology employed stakeholders-Inclusion Approach survey questionnaires in order to obtained the sustainable dimensional adaptation score. The results show that there is sustainable dimension gap in POEM evaluation, hence, suggested the pre- occupancy criteria did not fulfill the SDP adaptation and pre-occupancy criteria and variables if differ from post-occupancy criteria and variables.

  13. Improving the accuracy of energy baseline models for commercial buildings with occupancy data

    International Nuclear Information System (INIS)

    Liang, Xin; Hong, Tianzhen; Shen, Geoffrey Qiping

    2016-01-01

    Highlights: • We evaluated several baseline models predicting energy use in buildings. • Including occupancy data improved accuracy of baseline model prediction. • Occupancy is highly correlated with energy use in buildings. • This simple approach can be used in decision makings of energy retrofit projects. - Abstract: More than 80% of energy is consumed during operation phase of a building’s life cycle, so energy efficiency retrofit for existing buildings is considered a promising way to reduce energy use in buildings. The investment strategies of retrofit depend on the ability to quantify energy savings by “measurement and verification” (M&V), which compares actual energy consumption to how much energy would have been used without retrofit (called the “baseline” of energy use). Although numerous models exist for predicting baseline of energy use, a critical limitation is that occupancy has not been included as a variable. However, occupancy rate is essential for energy consumption and was emphasized by previous studies. This study develops a new baseline model which is built upon the Lawrence Berkeley National Laboratory (LBNL) model but includes the use of building occupancy data. The study also proposes metrics to quantify the accuracy of prediction and the impacts of variables. However, the results show that including occupancy data does not significantly improve the accuracy of the baseline model, especially for HVAC load. The reasons are discussed further. In addition, sensitivity analysis is conducted to show the influence of parameters in baseline models. The results from this study can help us understand the influence of occupancy on energy use, improve energy baseline prediction by including the occupancy factor, reduce risks of M&V and facilitate investment strategies of energy efficiency retrofit.

  14. Ignoring imperfect detection in biological surveys is dangerous: a response to 'fitting and interpreting occupancy models'.

    Directory of Open Access Journals (Sweden)

    Gurutzeta Guillera-Arroita

    Full Text Available In a recent paper, Welsh, Lindenmayer and Donnelly (WLD question the usefulness of models that estimate species occupancy while accounting for detectability. WLD claim that these models are difficult to fit and argue that disregarding detectability can be better than trying to adjust for it. We think that this conclusion and subsequent recommendations are not well founded and may negatively impact the quality of statistical inference in ecology and related management decisions. Here we respond to WLD's claims, evaluating in detail their arguments, using simulations and/or theory to support our points. In particular, WLD argue that both disregarding and accounting for imperfect detection lead to the same estimator performance regardless of sample size when detectability is a function of abundance. We show that this, the key result of their paper, only holds for cases of extreme heterogeneity like the single scenario they considered. Our results illustrate the dangers of disregarding imperfect detection. When ignored, occupancy and detection are confounded: the same naïve occupancy estimates can be obtained for very different true levels of occupancy so the size of the bias is unknowable. Hierarchical occupancy models separate occupancy and detection, and imprecise estimates simply indicate that more data are required for robust inference about the system in question. As for any statistical method, when underlying assumptions of simple hierarchical models are violated, their reliability is reduced. Resorting in those instances where hierarchical occupancy models do no perform well to the naïve occupancy estimator does not provide a satisfactory solution. The aim should instead be to achieve better estimation, by minimizing the effect of these issues during design, data collection and analysis, ensuring that the right amount of data is collected and model assumptions are met, considering model extensions where appropriate.

  15. The role of Dynamic Energy Budget theory in predictive modeling of stressor impacts on ecological systems. Comment on: ;Physics of metabolic organization; by Marko Jusup et al.

    Science.gov (United States)

    Galic, Nika; Forbes, Valery E.

    2017-03-01

    Human activities have been modifying ecosystems for centuries, from pressures on wild populations we harvest to modifying habitats through urbanization and agricultural activities. Changes in global climate patterns are adding another layer of, often unpredictable, perturbations to ecosystems on which we rely for life support [1,2]. To ensure the sustainability of ecosystem services, especially at this point in time when the human population is estimated to grow by another 2 billion by 2050 [3], we need to predict possible consequences of our actions and suggest relevant solutions [4,5]. We face several challenges when estimating adverse impacts of our actions on ecosystems. We describe these in the context of ecological risk assessment of chemicals. Firstly, when attempting to assess risk from exposure to chemicals, we base our decisions on a very limited number of species that are easily cultured and kept in the lab. We assume that preventing risk to these species will also protect all of the untested species present in natural ecosystems [6]. Secondly, although we know that chemicals interact with other stressors in the field, the number of stressors that we can test is limited due to logistical and ethical reasons. Similarly, empirical approaches are limited in both spatial and temporal scale due to logistical, financial and ethical reasons [7,8]. To bypass these challenges, we can develop ecological models that integrate relevant life history and other information and make testable predictions across relevant spatial and temporal scales [8-10].

  16. Psychosocial stressors contributing to emergency psychiatric service utilization in a sample of ethno-culturally diverse clients with psychosis in Toronto.

    Science.gov (United States)

    Rotenberg, Martin; Tuck, Andrew; McKenzie, Kwame

    2017-09-02

    Understanding the psychosocial stressors of people with psychoses from minority ethnic groups may help in the development of culturally appropriate services. This study aimed to compare psychosocial factors associated with attendance at an emergency department (ED) for six ethnic groups. Preventing crises or supporting people better in the community may decrease hospitalization and improve outcomes. A cohort was created by retrospective case note analysis of people of East-Asian, South-Asian, Black-African, Black-Caribbean, White-North American and White-European origin groups attending a specialized psychiatric ED in Toronto with a diagnosis of psychosis between 2009 and 2011. The psychological or social stressors which were linked to the presentation at the ED that were documented by the attending physicians were collected for this study. Logistic regression models were constructed to analyze the odds of presenting with specific stressors. Seven hundred sixty-five clients were included in this study. Forty-four percent of the sample did not have a psychiatrist, and 53% did not have a primary care provider. Social environmental stressors were the most frequent psychosocial stressor across all six groups, followed by issues in the primary support group, occupational and housing stressors. When compared to White-North American clients, East-Asian and White-European origin clients were less likely to present with a housing stressor, while Black-African clients had decreased odds of presenting with primary support group stressor. Having a primary care provider or psychiatrist were predominantly protective factors. In Toronto, moving people with chronic mental health conditions out of poverty, increasing the social safety net and improving access to primary care and community based mental health services may decrease many of the stressors which contribute to ED attendance.

  17. Developing a multi-stressor gradient for coral reefs | Science ...

    Science.gov (United States)

    Coral reefs are often found near coastal waters where multiple anthropogenic stressors co-occur at areas of human disturbance. Developing coral reef biocriteria under the U.S. Clean Water Act requires relationships between anthropogenic stressors and coral reef condition to be established. Developing stressor gradients presents challenges including: stressors which co-occur but operate at different or unknown spatial and temporal scales, inconsistent data availability measuring stressor levels, and unknown effects on exposed reef biota. We are developing a generalized stressor model using Puerto Rico as case study location, to represent the cumulative spatial/temporal co-occurrence of multiple anthropogenic stressors. Our approach builds on multi-stressor research in streams and rivers, and focuses on three high-priority stressors identified by coral reef experts: land-based sources of pollution (LBSP), global climate change (GCC) related temperature anomalies, and fishing pressure. Landscape development intensity index, based on land use/land cover data, estimates human impact in watersheds adjacent to coral reefs and is proxy for LBSP. NOAA’s retrospective daily thermal anomaly data is used to determine GCC thermal anomalies. Fishing pressure is modeled using gear-specific and fishery landings data. Stressor data was adjusted to a common scale or weighted for relative importance, buffered to account for diminished impact further from source, and compared wit

  18. Spatial occupancy models applied to atlas data show Southern Ground Hornbills strongly depend on protected areas.

    Science.gov (United States)

    Broms, Kristin M; Johnson, Devin S; Altwegg, Res; Conquest, Loveday L

    2014-03-01

    Determining the range of a species and exploring species--habitat associations are central questions in ecology and can be answered by analyzing presence--absence data. Often, both the sampling of sites and the desired area of inference involve neighboring sites; thus, positive spatial autocorrelation between these sites is expected. Using survey data for the Southern Ground Hornbill (Bucorvus leadbeateri) from the Southern African Bird Atlas Project, we compared advantages and disadvantages of three increasingly complex models for species occupancy: an occupancy model that accounted for nondetection but assumed all sites were independent, and two spatial occupancy models that accounted for both nondetection and spatial autocorrelation. We modeled the spatial autocorrelation with an intrinsic conditional autoregressive (ICAR) model and with a restricted spatial regression (RSR) model. Both spatial models can readily be applied to any other gridded, presence--absence data set using a newly introduced R package. The RSR model provided the best inference and was able to capture small-scale variation that the other models did not. It showed that ground hornbills are strongly dependent on protected areas in the north of their South African range, but less so further south. The ICAR models did not capture any spatial autocorrelation in the data, and they took an order, of magnitude longer than the RSR models to run. Thus, the RSR occupancy model appears to be an attractive choice for modeling occurrences at large spatial domains, while accounting for imperfect detection and spatial autocorrelation.

  19. Eating your feelings? Testing a model of employees' work-related stressors, sleep quality, and unhealthy eating.

    Science.gov (United States)

    Liu, Yihao; Song, Yifan; Koopmann, Jaclyn; Wang, Mo; Chang, Chu-Hsiang Daisy; Shi, Junqi

    2017-08-01

    Although organizational research on health-related behaviors has become increasingly popular, little attention has been paid to unhealthy eating. Drawing on the self-regulation perspective, we conducted 2 daily diary studies to examine the relationships between work-related stressors, sleep quality, negative mood, and eating behaviors. Study 1 sampled 125 participants from 5 Chinese information technology companies and showed that when participants experienced higher levels of job demands in the morning, they consumed more types of unhealthy food and fewer types of healthy food in the evening. In addition, sleep quality from the previous night buffered the effect of morning job demands on evening unhealthy food consumption. Study 2 used data from 110 customer service employees from a Chinese telecommunications company and further demonstrated a positive association between morning customer mistreatment and evening overeating behaviors, as well as the buffering effect of sleep quality. Results from Study 2 also supported afternoon negative mood as a mediator linking morning customer mistreatment to evening overeating behaviors. Finally, our findings revealed that the buffering effect of sleep quality was channeled through employees' vigor in the morning, which subsequently weakened the effect of customer mistreatment on negative mood. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  20. Occupant feedback based model predictive control for thermal comfort and energy optimization: A chamber experimental evaluation

    International Nuclear Information System (INIS)

    Chen, Xiao; Wang, Qian; Srebric, Jelena

    2016-01-01

    Highlights: • This study evaluates an occupant-feedback driven Model Predictive Controller (MPC). • The MPC adjusts indoor temperature based on a dynamic thermal sensation (DTS) model. • A chamber model for predicting chamber air temperature is developed and validated. • Experiments show that MPC using DTS performs better than using Predicted Mean Vote. - Abstract: In current centralized building climate control, occupants do not have much opportunity to intervene the automated control system. This study explores the benefit of using thermal comfort feedback from occupants in the model predictive control (MPC) design based on a novel dynamic thermal sensation (DTS) model. This DTS model based MPC was evaluated in chamber experiments. A hierarchical structure for thermal control was adopted in the chamber experiments. At the high level, an MPC controller calculates the optimal supply air temperature of the chamber heating, ventilation, and air conditioning (HVAC) system, using the feedback of occupants’ votes on thermal sensation. At the low level, the actual supply air temperature is controlled by the chiller/heater using a PI control to achieve the optimal set point. This DTS-based MPC was also compared to an MPC designed based on the Predicted Mean Vote (PMV) model for thermal sensation. The experiment results demonstrated that the DTS-based MPC using occupant feedback allows significant energy saving while maintaining occupant thermal comfort compared to the PMV-based MPC.

  1. Using a spatially structured life cycle model to assess the influence of multiple stressors on an exploited coastal-nursery-dependent population

    Science.gov (United States)

    Archambault, B.; Rivot, E.; Savina, M.; Le Pape, O.

    2018-02-01

    Exploited coastal-nursery-dependent fish species are subject to various stressors occurring at specific stages of the life cycle: climate-driven variability in hydrography determines the success of the first eggs/larvae stages; coastal nursery habitat suitability controls juvenile growth and survival; and fisheries target mostly adults. A life cycle approach was used to quantify the relative influence of these stressors on the Eastern English Channel (EEC) population of the common sole (Solea solea), a coastal-nursery-dependent flatfish population which sustains important fisheries. The common sole has a complex life cycle: after eggs hatch, larvae spend several weeks drifting in open water. Survivors go on to metamorphose into benthic fish. Juveniles spend the first two years of their life in coastal and estuarine nurseries. Close to maturation, they migrate to deeper areas, where different subpopulations supplied by different nurseries reproduce and are exploited by fisheries. A spatially structured age-and stage-based hierarchical Bayesian model integrating various aspects of ecological knowledge, data sources and expert knowledge was built to quantitatively describe this complex life cycle. The model included the low connectivity among three subpopulations in the EEC, the influence of hydrographic variability, the availability of suitable juvenile habitat and fisheries. Scenarios were designed to quantify the effects of interacting stressors on population renewal. Results emphasized the importance of coastal nursery habitat availability and quality for the population renewal. Realistic restoration scenarios of the highly degraded Seine estuary produced a two-third increase in catch potential for the adjacent subpopulation. Fisheries, however, remained the main source of population depletion. Setting fishing mortality to the maximum sustainable yield led to substantial increases in biomass (+100%) and catch (+33%) at the EEC scale. The approach also showed how

  2. The Union Health Center: a working model of clinical care linked to preventive occupational health services.

    Science.gov (United States)

    Herbert, R; Plattus, B; Kellogg, L; Luo, J; Marcus, M; Mascolo, A; Landrigan, P J

    1997-03-01

    As health care provision in the United States shifts to primary care settings, it is vital that new models of occupational health services be developed that link clinical care to prevention. The model program described in this paper was developed at the Union Health Center (UHC), a comprehensive health care center supported by the International Ladies Garment Workers Union (now the Union of Needletrades, Industrial and Textile Employees) serving a population of approximately 50,000 primarily minority, female garment workers in New York City. The objective of this paper is to describe a model occupational medicine program in a union-based comprehensive health center linking accessible clinical care with primary and secondary disease prevention efforts. To assess the presence of symptoms suggestive of occupational disease, a health status questionnaire was administered to female workers attending the UHC for routine health maintenance. Based on the results of this survey, an occupational medicine clinic was developed that integrated direct clinical care with worker and employer education and workplace hazard abatement. To assess the success of this new approach, selected cases of sentinel health events were tracked and a chart review was conducted after 3 years of clinic operation. Prior to initiation of the occupational medicine clinic, 64% (648) of the workers surveyed reported symptoms indicative of occupational illnesses. However, only 42 (4%) reported having been told by a physician that they had an occupational illness and only 4 (.4%) reported having field a workers' compensation claim for an occupational disease. In the occupational medicine clinic established at the UHC, a health and safety specialist acts as a case manager, coordinating worker and employer education as well as workplace hazard abatement focused on disease prevention, ensuring that every case of occupational disease is treated as a potential sentinel health event. As examples of the success

  3. [The application of two occupation health risk assessment models in a wooden furniture manufacturing industry].

    Science.gov (United States)

    Wang, A H; Leng, P B; Bian, G L; Li, X H; Mao, G C; Zhang, M B

    2016-10-20

    Objective: To explore the applicability of 2 different models of occupational health risk assessment in wooden furniture manufacturing industry. Methods: American EPA inhalation risk model and ICMM model of occupational health risk assessment were conducted to assess occupational health risk in a small wooden furniture enterprises, respectively. Results: There was poor protective measure and equipment of occupational disease in the plant. The concentration of wood dust in the air of two workshops was over occupational exposure limit (OEL) , and the C TWA was 8.9 mg/m 3 and 3.6 mg/m 3 , respectively. According to EPA model, the workers who exposed to benzene in this plant had high risk (9.7×10 -6 ~34.3×10 -6 ) of leukemia, and who exposed to formaldehyde had high risk (11.4 × 10 -6 ) of squamous cell carcinoma. There were inconsistent evaluation results using the ICMM tools of standard-based matrix and calculated risk rating. There were very high risks to be attacked by rhinocarcinoma of the workers who exposed to wood dust for the tool of calculated risk rating, while high risk for the tool of standard-based matrix. For the workers who exposed to noise, risk of noise-induced deafness was unacceptable and medium risk using two tools, respectively. Conclusion: Both EPA model and ICMM model can appropriately predict and assessthe occupational health risk in wooden furniture manufactory, ICMM due to the relatively simple operation, easy evaluation parameters, assessment of occupational - disease - inductive factors comprehensively, and more suitable for wooden furniture production enterprise.

  4. Occupations at Risk and Organizational Well-Being: An Empirical Test of a Job Insecurity Integrated Model.

    Science.gov (United States)

    Chirumbolo, Antonio; Urbini, Flavio; Callea, Antonino; Lo Presti, Alessandro; Talamo, Alessandra

    2017-01-01

    One of the more visible effects of the societal changes is the increased feelings of uncertainty in the workforce. In fact, job insecurity represents a crucial occupational risk factor and a major job stressor that has negative consequences on both organizational well-being and individual health. Many studies have focused on the consequences about the fear and the perception of losing the job as a whole (called quantitative job insecurity), while more recently research has begun to examine more extensively the worries and the perceptions of losing valued job features (called qualitative job insecurity). The vast majority of the studies, however, have investigated the effects of quantitative and qualitative job insecurity separately. In this paper, we proposed the Job Insecurity Integrated Model aimed to examine the effects of quantitative job insecurity and qualitative job insecurity on their short-term and long-term outcomes. This model was empirically tested in two independent studies, hypothesizing that qualitative job insecurity mediated the effects of quantitative job insecurity on different outcomes, such as work engagement and organizational identification (Study 1), and job satisfaction, commitment, psychological stress and turnover intention (Study 2). Study 1 was conducted on 329 employees in private firms, while Study 2 on 278 employees in both public sector and private firms. Results robustly showed that qualitative job insecurity totally mediated the effects of quantitative on all the considered outcomes. By showing that the effects of quantitative job insecurity on its outcomes passed through qualitative job insecurity, the Job Insecurity Integrated Model contributes to clarifying previous findings in job insecurity research and puts forward a framework that could profitably produce new investigations with important theoretical and practical implications.

  5. Occupations at Risk and Organizational Well-Being: An Empirical Test of a Job Insecurity Integrated Model

    Science.gov (United States)

    Chirumbolo, Antonio; Urbini, Flavio; Callea, Antonino; Lo Presti, Alessandro; Talamo, Alessandra

    2017-01-01

    One of the more visible effects of the societal changes is the increased feelings of uncertainty in the workforce. In fact, job insecurity represents a crucial occupational risk factor and a major job stressor that has negative consequences on both organizational well-being and individual health. Many studies have focused on the consequences about the fear and the perception of losing the job as a whole (called quantitative job insecurity), while more recently research has begun to examine more extensively the worries and the perceptions of losing valued job features (called qualitative job insecurity). The vast majority of the studies, however, have investigated the effects of quantitative and qualitative job insecurity separately. In this paper, we proposed the Job Insecurity Integrated Model aimed to examine the effects of quantitative job insecurity and qualitative job insecurity on their short-term and long-term outcomes. This model was empirically tested in two independent studies, hypothesizing that qualitative job insecurity mediated the effects of quantitative job insecurity on different outcomes, such as work engagement and organizational identification (Study 1), and job satisfaction, commitment, psychological stress and turnover intention (Study 2). Study 1 was conducted on 329 employees in private firms, while Study 2 on 278 employees in both public sector and private firms. Results robustly showed that qualitative job insecurity totally mediated the effects of quantitative on all the considered outcomes. By showing that the effects of quantitative job insecurity on its outcomes passed through qualitative job insecurity, the Job Insecurity Integrated Model contributes to clarifying previous findings in job insecurity research and puts forward a framework that could profitably produce new investigations with important theoretical and practical implications. PMID:29250013

  6. Occupations at Risk and Organizational Well-Being: An Empirical Test of a Job Insecurity Integrated Model

    Directory of Open Access Journals (Sweden)

    Antonio Chirumbolo

    2017-11-01

    Full Text Available One of the more visible effects of the societal changes is the increased feelings of uncertainty in the workforce. In fact, job insecurity represents a crucial occupational risk factor and a major job stressor that has negative consequences on both organizational well-being and individual health. Many studies have focused on the consequences about the fear and the perception of losing the job as a whole (called quantitative job insecurity, while more recently research has begun to examine more extensively the worries and the perceptions of losing valued job features (called qualitative job insecurity. The vast majority of the studies, however, have investigated the effects of quantitative and qualitative job insecurity separately. In this paper, we proposed the Job Insecurity Integrated Model aimed to examine the effects of quantitative job insecurity and qualitative job insecurity on their short-term and long-term outcomes. This model was empirically tested in two independent studies, hypothesizing that qualitative job insecurity mediated the effects of quantitative job insecurity on different outcomes, such as work engagement and organizational identification (Study 1, and job satisfaction, commitment, psychological stress and turnover intention (Study 2. Study 1 was conducted on 329 employees in private firms, while Study 2 on 278 employees in both public sector and private firms. Results robustly showed that qualitative job insecurity totally mediated the effects of quantitative on all the considered outcomes. By showing that the effects of quantitative job insecurity on its outcomes passed through qualitative job insecurity, the Job Insecurity Integrated Model contributes to clarifying previous findings in job insecurity research and puts forward a framework that could profitably produce new investigations with important theoretical and practical implications.

  7. Modelling of occupational exposure to inhalable nickel compounds.

    Science.gov (United States)

    Kendzia, Benjamin; Pesch, Beate; Koppisch, Dorothea; Van Gelder, Rainer; Pitzke, Katrin; Zschiesche, Wolfgang; Behrens, Thomas; Weiss, Tobias; Siemiatycki, Jack; Lavoué, Jerome; Jöckel, Karl-Heinz; Stamm, Roger; Brüning, Thomas

    2017-07-01

    The aim of this study was to estimate average occupational exposure to inhalable nickel (Ni) using the German exposure database MEGA. This database contains 8052 personal measurements of Ni collected between 1990 and 2009 in adjunct with information on the measurement and workplace conditions. The median of all Ni concentrations was 9 μg/m 3 and the 95th percentile was 460 μg/m 3 . We predicted geometric means (GMs) for welders and other occupations centered to 1999. Exposure to Ni in welders is strongly influenced by the welding process applied and the Ni content of the used welding materials. Welding with consumable electrodes of high Ni content (>30%) was associated with 10-fold higher concentrations compared with those with a low content (exposure levels (GMs ≥20 μg/m 3 ) were observed in gas metal and shielded metal arc welders using welding materials with high Ni content, in metal sprayers, grinders and forging-press operators, and in the manufacture of batteries and accumulators. The exposure profiles are useful for exposure assessment in epidemiologic studies as well as in industrial hygiene. Therefore, we recommend to collect additional exposure-specific information in addition to the job title in community-based studies when estimating the health risks of Ni exposure.

  8. Parents' explanatory models and hopes for outcomes of occupational therapy using a sensory integration approach.

    Science.gov (United States)

    Cohn, Ellen S; Kramer, Jessica; Schub, Jamie A; May-Benson, Teresa

    2014-01-01

    PURPOSE. To describe parents' concerns and hopes for their children who would be receiving occupational therapy using a sensory integration approach. METHOD. Content analysis of 275 parental responses to three open-ended questions on developmental-sensory history intake forms. FINDINGS. Parents' descriptions of why they sought for their children were categorized into four overarching concerns about their children's challenges: self-regulation, interacting with peers, participating in skilled motor activities, and self-confidence. Parents often linked these concerns together, revealing explanatory models of how they make sense of potential relationships among their children's challenges and how these challenges affect occupational performance. Parents hoped occupational therapy would help their children develop self-understanding and frustration tolerance to self-regulate their behavior in socially acceptable ways. IMPLICATIONS. Assessment and intervention should explicitly focus on links among self-regulation, social participation, skills, and perceived competence to address parents' expectations. Copyright © 2014 by the American Occupational Therapy Association, Inc.

  9. Stressors and reactions to stressors among university students.

    Science.gov (United States)

    Hamaideh, Shaher H

    2011-01-01

    University students are prone to stressors due to the transitional nature of university life. High levels of stress are believed to affect students' health as well as their academic performance. The aims of this study were to identify stressors and reactions to stressors among university students, and to examine the correlations between student stressors and study variables. A correlational descriptive design was used. Student-life Stress Inventory (SSI) was used to measure the stressors and reactions to stressors. Stratified random sampling was employed to recruit participants. The final sample consisted of 877 participants (students). s indicated that the highest group of stressors experienced by students were 'self-imposed' stressors followed by 'pressures'. Cognitive responses were found to be the highest responses to stressors experienced by students. Negative correlations were found with student's perception of health, and father's and mother's level of education. This study revealed that stressors among university students come from 'self-imposed' stressors and 'pressures'. Stress management, assertiveness skills, time management and counselling sessions will be effective in reducing stress experienced by students.

  10. The relationship between occupational culture dimensions and reward preferences: A structural equation modelling approach

    Directory of Open Access Journals (Sweden)

    Mark Bussin

    2016-06-01

    Full Text Available Orientation: Reward has links to employee attraction and retention and as such has a role to play in managing talent. However, despite a range of research, there is still lack of clarity on employee preferences relating to reward. Research purpose: The purpose of the research was to recommend and appraise a theoretical model of the relationship between occupational culture dimensions and reward preferences of specific occupational groups in the South African context. Motivation for the study: The motivation for this study was to address the gap that exists with reward preferences and occupational culture with a view to identifying and gaining insight into individual preferences. Research design, approach and method: A structural equation modelling approach was adopted in exploring the proposed relationships. A South African Information, Communication, and Technology (ICT organisation served as the population, and a web-based survey assisted in gathering study data (n = 1362. Main findings: The findings provided support for the relationship between occupational culture dimensions and certain reward preferences. In particular, statistically significant results were obtained with the inclusion of the Environment, Team, and Time occupational culture dimensions as independent variables. Practical implications and value-add: The study provides workable input to organisations and reward professionals in the design of their reward strategies and programmes. Keywords: compensation; employee preferences; occupational culture; remuneration; reward preferences

  11. Why employees with higher challenging appraisals style are more affectively engaged at work? The role of challenging stressors: a moderated mediation model.

    Science.gov (United States)

    Lin, Shin-Huei; Wu, Chia-Huei; Chen, Mei-Yen; Chen, Lung Hung

    2014-10-01

    Challenging stressors have been positively linked to various work outcomes. However, the role of individual differences in stress appraisal in shaping the function of challenging stressors and work outcomes has been rarely discussed. Drawing on the individual differences perspective, the authors propose that employees higher in challenge appraisal are more likely to have challenging stressors and are more responsive to such stressors to have a higher positive affect at work. Results obtained from 117 employees supported the hypotheses. The results indicated that challenge appraisal is positively related to challenging stressors. In addition, challenging stressors has a positive association with positive affect at work when challenge appraisal is high but has a null association when challenge appraisal is low. The findings suggest that challenging stressors does not necessarily bring positive work outcomes as suggested in past studies and highlight the importance of considering dispositional tendency in stress appraisal when looking into the function of challenging stressors and work outcomes. © 2014 International Union of Psychological Science.

  12. Life-Long Implications of Developmental Exposure to Environmental Stressors

    DEFF Research Database (Denmark)

    Grandjean, Philippe; Barouki, Robert; Bellinger, David C

    2015-01-01

    The Developmental Origins of Health and Disease (DOHaD) paradigm is one of the most rapidly expanding areas of biomedical research. Environmental stressors that can impact on DOHaD encompass a variety of environmental and occupational hazards as well as deficiency and oversupply of nutrients and ...

  13. Occupational safety and health program for a model uranium mill

    International Nuclear Information System (INIS)

    Miller, H.T.

    1981-01-01

    The basic purpose of this paper is to suggest procedures and practices to insure that no employee working in a uranium milling operation receives exposure to radioactive, toxic, or other materials or agents that might produce a permanent, deleterious effect upon his physical health and well-being. This program is also designed to insure that each employee can carry out his assigned duties without risk to his health or to that of his fellow workers. The total program is envisioned as a balanced combination of occupational hygiene and radiation monitoring. This includes surveying, air sampling, personnel dosimetry, bioassay, medical surveillance, epidemiology, and training - all backed by a thoroughly tested and evaluated set of emergency procedures. The program, as presented, is keyed to the results of monitoring, surveying, air sampling, medical surveillance, and epidemiology - it being obvious that no problem can result when no hazard can be identified

  14. Using occupancy models of forest breeding birds to prioritize conservation planning

    Science.gov (United States)

    De Wan, A. A.; Sullivan, P.J.; Lembo, A.J.; Smith, C.R.; Maerz, J.C.; Lassoie, J.P.; Richmond, M.E.

    2009-01-01

    As urban development continues to encroach on the natural and rural landscape, land-use planners struggle to identify high priority conservation areas for protection. Although knowing where urban-sensitive species may be occurring on the landscape would facilitate conservation planning, research efforts are often not sufficiently designed to make quality predictions at unknown locations. Recent advances in occupancy modeling allow for more precise estimates of occupancy by accounting for differences in detectability. We applied these techniques to produce robust estimates of habitat occupancy for a subset of forest breeding birds, a group that has been shown to be sensitive to urbanization, in a rapidly urbanizing yet biological diverse region of New York State. We found that detection probability ranged widely across species, from 0.05 to 0.8. Our models suggest that detection probability declined with increasing forest fragmentation. We also found that the probability of occupancy of forest breeding birds is negatively influenced by increasing perimeter-area ratio of forest fragments and urbanization in the surrounding habitat matrix. We capitalized on our random sampling design to produce spatially explicit models that predict high priority conservation areas across the entire region, where interior-species were most likely to occur. Finally, we use our predictive maps to demonstrate how a strict sampling design coupled with occupancy modeling can be a valuable tool for prioritizing biodiversity conservation in land-use planning. ?? 2009 Elsevier Ltd.

  15. Police work stressors and cardiac vagal control.

    Science.gov (United States)

    Andrew, Michael E; Violanti, John M; Gu, Ja K; Fekedulegn, Desta; Li, Shengqiao; Hartley, Tara A; Charles, Luenda E; Mnatsakanova, Anna; Miller, Diane B; Burchfiel, Cecil M

    2017-09-10

    This study examines relationships between the frequency and intensity of police work stressors and cardiac vagal control, estimated using the high frequency component of heart rate variability (HRV). This is a cross-sectional study of 360 officers from the Buffalo New York Police Department. Police stress was measured using the Spielberger police stress survey, which includes exposure indices created as the product of the self-evaluation of how stressful certain events were and the self-reported frequency with which they occurred. Vagal control was estimated using the high frequency component of resting HRV calculated in units of milliseconds squared and reported in natural log scale. Associations between police work stressors and vagal control were examined using linear regression for significance testing and analysis of covariance for descriptive purposes, stratified by gender, and adjusted for age and race/ethnicity. There were no significant associations between police work stressor exposure indices and vagal control among men. Among women, the inverse associations between the lack of support stressor exposure and vagal control were statistically significant in adjusted models for indices of exposure over the past year (lowest stressor quartile: M = 5.57, 95% CI 5.07 to 6.08, and highest stressor quartile: M = 5.02, 95% CI 4.54 to 5.51, test of association from continuous linear regression of vagal control on lack of support stressor β = -0.273, P = .04). This study supports an inverse association between lack of organizational support and vagal control among female but not male police officers. © 2017 Wiley Periodicals, Inc.

  16. Reconceptualizing synergism and antagonism among multiple stressors.

    Science.gov (United States)

    Piggott, Jeremy J; Townsend, Colin R; Matthaei, Christoph D

    2015-04-01

    The potential for complex synergistic or antagonistic interactions between multiple stressors presents one of the largest uncertainties when predicting ecological change but, despite common use of the terms in the scientific literature, a consensus on their operational definition is still lacking. The identification of synergism or antagonism is generally straightforward when stressors operate in the same direction, but if individual stressor effects oppose each other, the definition of synergism is paradoxical because what is synergistic to one stressor's effect direction is antagonistic to the others. In their highly cited meta-analysis, Crain et al. (Ecology Letters, 11, 2008: 1304) assumed in situations with opposing individual effects that synergy only occurs when the cumulative effect is more negative than the additive sum of the opposing individual effects. We argue against this and propose a new systematic classification based on an additive effects model that combines the magnitude and response direction of the cumulative effect and the interaction effect. A new class of "mitigating synergism" is identified, where cumulative effects are reversed and enhanced. We applied our directional classification to the dataset compiled by Crain et al. (Ecology Letters, 11, 2008: 1304) to determine the prevalence of synergistic, antagonistic, and additive interactions. Compared to their original analysis, we report differences in the representation of interaction classes by interaction type and we document examples of mitigating synergism, highlighting the importance of incorporating individual stressor effect directions in the determination of synergisms and antagonisms. This is particularly pertinent given a general bias in ecology toward investigating and reporting adverse multiple stressor effects (double negative). We emphasize the need for reconsideration by the ecological community of the interpretation of synergism and antagonism in situations where

  17. Journalists' Occupational Stress: A Comparative Study between Reporting Critical Events and Domestic News.

    Science.gov (United States)

    Monteiro, Susana; Marques-Pinto, Alexandra

    2017-07-27

    Nowadays, journalism is considered a stressful occupation, not only due to the stress perceived in journalists' daily work but also due to the critical, potentially traumatic events they report. However, research on journalists' occupational stress in both these professional settings is still scarce. This study aims to characterize and compare occupational stress variables perceived by journalists in their daily work and in critical scenarios. Taking the Holistic Model of Occupational Stress by Nelson and Simmons (2003) as a framework, 25 Portuguese journalists, all with experience in reporting critical events, were interviewed on their perceptions of some core variables of the model: occupational stressors, distress and eustress emotional reactions, and the consequences of these experiences on their well-being. Differences among these core variables, according to the number of deployments to a critical event, were statistically analysed in order to ascertain whether repeated exposure to trauma influenced journalists' occupational stress perceptions. The data content analysis showed that occupational stressors and emotional reactions differed across settings, while the consequences associated with journalists' experiences were perceived as being mainly negative in both occupational contexts. Significant differences were identified in some of these variables according to the number of deployments to a critical event (p studies.

  18. Monitoring carnivore populations at the landscape scale: occupancy modelling of tigers from sign surveys

    Science.gov (United States)

    Karanth, Kota Ullas; Gopalaswamy, Arjun M.; Kumar, Narayanarao Samba; Vaidyanathan, Srinivas; Nichols, James D.; MacKenzie, Darryl I.

    2011-01-01

    1. Assessing spatial distributions of threatened large carnivores at landscape scales poses formidable challenges because of their rarity and elusiveness. As a consequence of logistical constraints, investigators typically rely on sign surveys. Most survey methods, however, do not explicitly address the central problem of imperfect detections of animal signs in the field, leading to underestimates of true habitat occupancy and distribution. 2. We assessed habitat occupancy for a tiger Panthera tigris metapopulation across a c. 38 000-km2 landscape in India, employing a spatially replicated survey to explicitly address imperfect detections. Ecological predictions about tiger presence were confronted with sign detection data generated from occupancy sampling of 205 sites, each of 188 km2. 3. A recent occupancy model that considers Markovian dependency among sign detections on spatial replicates performed better than the standard occupancy model (ΔAIC = 184·9). A formulation of this model that fitted the data best showed that density of ungulate prey and levels of human disturbance were key determinants of local tiger presence. Model averaging resulted in a replicate-level detection probability [inline image] = 0·17 (0·17) for signs and a tiger habitat occupancy estimate of [inline image] = 0·665 (0·0857) or 14 076 (1814) km2 of potential habitat of 21 167 km2. In contrast, a traditional presence-versus-absence approach underestimated occupancy by 47%. Maps of probabilities of local site occupancy clearly identified tiger source populations at higher densities and matched observed tiger density variations, suggesting their potential utility for population assessments at landscape scales. 4. Synthesis and applications. Landscape-scale sign surveys can efficiently assess large carnivore spatial distributions and elucidate the factors governing their local presence, provided ecological and observation processes are both explicitly modelled. Occupancy

  19. Using occupancy models to understand the distribution of an amphibian pathogen, Batrachochytrium dendrobatidis

    Science.gov (United States)

    Adams, Michael J.; Chelgren, Nathan; Reinitz, David M.; Cole, Rebecca A.; Rachowicz, L.J.; Galvan, Stephanie; Mccreary, Brome; Pearl, Christopher A.; Bailey, Larissa L.; Bettaso, Jamie B.; Bull, Evelyn L.; Leu, Matthias

    2010-01-01

    Batrachochytrium dendrobatidis is a fungal pathogen that is receiving attention around the world for its role in amphibian declines. Study of its occurrence patterns is hampered by false negatives: the failure to detect the pathogen when it is present. Occupancy models are a useful but currently underutilized tool for analyzing detection data when the probability of detecting a species is <1. We use occupancy models to evaluate hypotheses concerning the occurrence and prevalence of B. dendrobatidis and discuss how this application differs from a conventional occupancy approach. We found that the probability of detecting the pathogen, conditional on presence of the pathogen in the anuran population, was related to amphibian development stage, day of the year, elevation, and human activities. Batrachochytrium dendrobatidis was found throughout our study area but was only estimated to occur in 53.4% of 78 populations of native amphibians and 66.4% of 40 populations of nonnative Rana catesbeiana tested. We found little evidence to support any spatial hypotheses concerning the probability that the pathogen occurs in a population, but did find evidence of some taxonomic variation. We discuss the interpretation of occupancy model parameters, when, unlike a conventional occupancy application, the number of potential samples or observations is finite.

  20. On 4-degree-of-freedom biodynamic models of seated occupants: Lumped-parameter modeling

    Science.gov (United States)

    Bai, Xian-Xu; Xu, Shi-Xu; Cheng, Wei; Qian, Li-Jun

    2017-08-01

    It is useful to develop an effective biodynamic model of seated human occupants to help understand the human vibration exposure to transportation vehicle vibrations and to help design and improve the anti-vibration devices and/or test dummies. This study proposed and demonstrated a methodology for systematically identifying the best configuration or structure of a 4-degree-of-freedom (4DOF) human vibration model and for its parameter identification. First, an equivalent simplification expression for the models was made. Second, all of the possible 23 structural configurations of the models were identified. Third, each of them was calibrated using the frequency response functions recommended in a biodynamic standard. An improved version of non-dominated sorting genetic algorithm (NSGA-II) based on Pareto optimization principle was used to determine the model parameters. Finally, a model evaluation criterion proposed in this study was used to assess the models and to identify the best one, which was based on both the goodness of curve fits and comprehensive goodness of the fits. The identified top configurations were better than those reported in the literature. This methodology may also be extended and used to develop the models with other DOFs.

  1. Callings and Work Engagement: Moderated Mediation Model of Work Meaningfulness, Occupational Identity, and Occupational Self-Efficacy

    Science.gov (United States)

    Hirschi, Andreas

    2012-01-01

    Scholarly interest in callings is growing, but researchers' understanding of how and when callings relate to career outcomes is incomplete. The present study investigated the possibility that the relationship of calling to work engagement is mediated by work meaningfulness, occupational identity, and occupational self-efficacy--and that this…

  2. Development of a multi-body nonlinear model for a seat-occupant system

    Science.gov (United States)

    Azizi, Yousof

    A car seat is an important component of today's cars, which directly affects ride comfort experienced by occupants. Currently, the process of ride comfort evaluation is subjective. Alternatively, the ride comfort can be evaluated by a series of objective metrics in the dynamic response of the occupant. From previous studies it is well known that the dynamic behavior of a seat-occupant system is greatly affected by soft nonlinear viscoelastic materials used in the seat cushion. Therefore, in this research, especial attention was given to efficiently modeling the behavior of seat cushion. In the first part of this research, a phenomenological nonlinear viscoelastic foam model was proposed and its ability to capture uniaxial behavior of foam was investigated. The model is based on the assumption that the total stress can be decomposed into the sum of a nonlinear elastic component, modeled by a higher order polynomial of strain, and a nonlinear hereditary type viscoelastic component. System identification procedures were developed to estimate the model parameters using uniaxial cyclic compression data from experiments conducted at different rates on two types of low density polyurethane foams and three types of high density CONFOR foams. The performance of the proposed model was compared to that of other traditional continuum models. For each foam type, it was observed that lower order models are sufficient to describe the uniaxial behavior of the foam compressed at different rates. Although, the estimated model parameters were functions of the input strain rate. Alternatively, higher order comprehensive models, with strain independent parameters, were estimated as well. The estimated comprehensive model predicts foam responses under different compression rates. Also, a methodology was proposed to predict the stress-response of a layered foam system using the estimated models of each foam in the layers. Next, the estimated foam model was incorporated into a single

  3. Occupancy modeling of autonomously recorded vocalizations to predict distribution of rallids in tidal wetlands

    Science.gov (United States)

    Stiffler, Lydia L.; Anderson, James T.; Katzner, Todd

    2018-01-01

    Conservation and management for a species requires reliable information on its status, distribution, and habitat use. We identified occupancy and distributions of king (Rallus elegans) and clapper (R. crepitans) rail populations in marsh complexes along the Pamunkey and Mattaponi Rivers in Virginia, USA by modeling data on vocalizations recorded from autonomous recording units (ARUs). Occupancy probability for both species combined was 0.64 (95% CI: 0.53, 0.75) in marshes along the Pamunkey and 0.59 (0.45, 0.72) in marshes along the Mattaponi. Occupancy probability along the Pamunkey was strongly influenced by salinity, increasing logistically by a factor of 1.62 (0.6, 2.65) per parts per thousand of salinity. In contrast, there was not a strong salinity gradient on the Mattaponi and therefore vegetative community structure determined occupancy probability on that river. Estimated detection probability across both marshes was 0.63 (0.62, 0.65), but detection rates decreased as the season progressed. Monitoring wildlife within wetlands presents unique challenges for conservation managers. Our findings provide insight not only into how rails responded to environmental variation but also into the general utility of ARUs for occupancy modeling of the distribution and habitat associations of rails within tidal marsh systems.

  4. Prioritizing ecological restoration among sites in multi-stressor landscapes.

    Science.gov (United States)

    Neeson, Thomas M; Smith, Sigrid D P; Allan, J David; McIntyre, Peter B

    2016-09-01

    Most ecosystems are impacted by multiple local and long-distance stressors, many of which interact in complex ways. We present a framework for prioritizing ecological restoration efforts among sites in multi-stressor landscapes. Using a simple model, we show that both the economic and sociopolitical costs of restoration will typically be lower at sites with a relatively small number of severe problems than at sites with numerous lesser problems. Based on these results, we propose using cumulative stress and evenness of stressor impact as complementary indices that together reflect key challenges of restoring a site to improved condition. To illustrate this approach, we analyze stressor evenness across the world's rivers and the Laurentian Great Lakes. This exploration reveals that evenness and cumulative stress are decoupled, enabling selection of sites where remediating a modest number of high-intensity stressors could substantially reduce cumulative stress. Just as species richness and species evenness are fundamental axes of biological diversity, we argue that cumulative stress and stressor evenness constitute fundamental axes for identifying restoration opportunities in multi-stressor landscapes. Our results highlight opportunities to boost restoration efficiency through strategic use of multi-stressor datasets to identify sites that maximize ecological response per stressor remediated. This prioritization framework can also be expanded to account for the feasibility of remediation and the expected societal benefits of restoration projects. © 2016 by the Ecological Society of America.

  5. Use of Occupancy Models to Evaluate Expert Knowledge-based Species-Habitat Relationships

    Directory of Open Access Journals (Sweden)

    Monica N. Iglecia

    2012-12-01

    Full Text Available Expert knowledge-based species-habitat relationships are used extensively to guide conservation planning, particularly when data are scarce. Purported relationships describe the initial state of knowledge, but are rarely tested. We assessed support in the data for suitability rankings of vegetation types based on expert knowledge for three terrestrial avian species in the South Atlantic Coastal Plain of the United States. Experts used published studies, natural history, survey data, and field experience to rank vegetation types as optimal, suitable, and marginal. We used single-season occupancy models, coupled with land cover and Breeding Bird Survey data, to examine the hypothesis that patterns of occupancy conformed to species-habitat suitability rankings purported by experts. Purported habitat suitability was validated for two of three species. As predicted for the Eastern Wood-Pewee (Contopus virens and Brown-headed Nuthatch (Sitta pusilla, occupancy was strongly influenced by vegetation types classified as "optimal habitat" by the species suitability rankings for nuthatches and wood-pewees. Contrary to predictions, Red-headed Woodpecker (Melanerpes erythrocephalus models that included vegetation types as covariates received similar support by the data as models without vegetation types. For all three species, occupancy was also related to sampling latitude. Our results suggest that covariates representing other habitat requirements might be necessary to model occurrence of generalist species like the woodpecker. The modeling approach described herein provides a means to test expert knowledge-based species-habitat relationships, and hence, help guide conservation planning.

  6. Secretaries' Perceived Strategies for Coping with Occupational ...

    African Journals Online (AJOL)

    Secretaries' Perceived Strategies for Coping with Occupational Stress in Banks in Anambra State. ... Journal Home > Vol 9, No 3 (2015) > ... Results revealed that bank secretaries perceived work functions as cause of stress; these stressors ...

  7. Development of Optimal Stressor Scenarios for New Operational Energy Systems

    Science.gov (United States)

    2017-12-01

    OPTIMAL STRESSOR SCENARIOS FOR NEW OPERATIONAL ENERGY SYSTEMS by Geoffrey E. Fastabend December 2017 Thesis Advisor: Alejandro S... ENERGY SYSTEMS 5. FUNDING NUMBERS 6. AUTHOR(S) Geoffrey E. Fastabend 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Naval Postgraduate School...developed and tested simulation model for operational energy related systems in order to develop better stressor scenarios for acceptance testing

  8. Daily Stressors in School-Age Children: A Multilevel Approach

    Science.gov (United States)

    Escobar, Milagros; Alarcón, Rafael; Blanca, María J.; Fernández-Baena, F. Javier; Rosel, Jesús F.; Trianes, María Victoria

    2013-01-01

    This study uses hierarchical or multilevel modeling to identify variables that contribute to daily stressors in a population of schoolchildren. Four hierarchical levels with several predictive variables were considered: student (age, sex, social adaptation of the student, number of life events and chronic stressors experienced, and educational…

  9. Can occupancy-abundance models be used to monitor wolf abundance?

    Directory of Open Access Journals (Sweden)

    M Cecilia Latham

    Full Text Available Estimating the abundance of wild carnivores is of foremost importance for conservation and management. However, given their elusive habits, direct observations of these animals are difficult to obtain, so abundance is more commonly estimated from sign surveys or radio-marked individuals. These methods can be costly and difficult, particularly in large areas with heavy forest cover. As an alternative, recent research has suggested that wolf abundance can be estimated from occupancy-abundance curves derived from "virtual" surveys of simulated wolf track networks. Although potentially more cost-effective, the utility of this approach hinges on its robustness to violations of its assumptions. We assessed the sensitivity of the occupancy-abundance approach to four assumptions: variation in wolf movement rates, changes in pack cohesion, presence of lone wolves, and size of survey units. Our simulations showed that occupancy rates and wolf pack abundances were biased high if track surveys were conducted when wolves made long compared to short movements, wolf packs were moving as multiple hunting units as opposed to a cohesive pack, and lone wolves were moving throughout the surveyed landscape. We also found that larger survey units (400 and 576 km2 were more robust to changes in these factors than smaller survey units (36 and 144 km2. However, occupancy rates derived from large survey units rapidly reached an asymptote at 100% occupancy, suggesting that these large units are inappropriate for areas with moderate to high wolf densities (>15 wolves/1,000 km2. Virtually-derived occupancy-abundance relationships can be a useful method for monitoring wolves and other elusive wildlife if applied within certain constraints, in particular biological knowledge of the surveyed species needs to be incorporated into the design of the occupancy surveys. Further, we suggest that the applicability of this method could be extended by directly incorporating some of its

  10. Statement on the suitability of the BEEHAVE model for its potential use in a regulatory context and for the risk assessment of multiple stressors in honeybees at the landscape level

    DEFF Research Database (Denmark)

    EFSA PPR Panel (EFSA Panel on Plant Protection Products and their Residues); Topping, Christopher John

    2015-01-01

    The Panel has interpreted the Terms of Reference by carrying out a stepwise evaluation of the BEEHAVE simulation model with a view to assessing its suitability for use in a regulatory context and for risk assessment of multiple stressors at the landscape level. The EFSA opinion on good modelling...... practice was used to evaluate the model and its documentation systematically. The overall conclusion is that BEEHAVE performs well in modelling honeybee colony dynamics, and the supporting documentation is generally good but does not fully meet the criteria of the good modelling opinion. BEEHAVE is not yet...... of the effects of interactions of pesticides with multiple stressors. BEEHAVE currently uses a very simple representation of a landscape and this should be extended. There is only one environmental scenario in the present version of BEEHAVE (European central zone—weather scenarios for Germany and the UK...

  11. INCORPORATING NONCHEMICAL STRESSORS INTO CUMMULATIVE RISK ASSESSMENTS

    Science.gov (United States)

    The risk assessment paradigm has begun to shift from assessing single chemicals using "reasonable worst case" assumptions for individuals to considering multiple chemicals and community-based models. Inherent in community-based risk assessment is examination of all stressors a...

  12. Accounting for false-positive acoustic detections of bats using occupancy models

    Science.gov (United States)

    Clement, Matthew J.; Rodhouse, Thomas J.; Ormsbee, Patricia C.; Szewczak, Joseph M.; Nichols, James D.

    2014-01-01

    1. Acoustic surveys have become a common survey method for bats and other vocal taxa. Previous work shows that bat echolocation may be misidentified, but common analytic methods, such as occupancy models, assume that misidentifications do not occur. Unless rare, such misidentifications could lead to incorrect inferences with significant management implications.

  13. Modelling Occupational Stress and Employee Health and Wellbeing in a Chinese Higher Education Institution

    Science.gov (United States)

    Sang, Xiaoli; Teo, Stephen T. T.; Cooper, Cary L.; Bohle, Philip

    2013-01-01

    Extensive change is evident in higher education in the People's Republic of China but there have been few studies of the effect of work stress on wellbeing in the higher education sector. The main aim of this study is to test and refine the ASSET ("An Organizational Stress Screening Tool") model of occupational stress in a sample of 150…

  14. Extending the Challenge-Hindrance Model of Occupational Stress: The Role of Appraisal

    Science.gov (United States)

    Webster, Jennica R.; Beehr, Terry A.; Love, Kevin

    2011-01-01

    Interest regarding the challenge-hindrance occupational stress model has increased in recent years, however its theoretical foundation has not been tested. Drawing from the transactional theory of stress, this study tests the assumptions made in past research (1) that workload and responsibility are appraised as challenges and role ambiguity and…

  15. [Prevention of occupational accidents with biological material as per Green and Kreuter Model].

    Science.gov (United States)

    Manetti, Marcela Luisa; da Costa, João Carlos Souza; Marziale, Maria Helena Palucci; Trovó, Marli Elisa

    2006-03-01

    This study aimed at diagnosing the occurrence of occupational accidents deriving from exposition to biological substance among workers of a hospital from São Paulo, Brazil, analyzing the adopted safety measures and elaborating a flowchart of preventive actions according to the Health Promotion Model by Green and Kreuter. It is an exploratory study with data collected electronically from the website REPAT - Electronic Network for the Prevention of Occupational Accidents with biological substances. The strategy used by the hospital did not reduce the injures. Results were used to elaborate a flowchart of preventive actions in order to improve the workers' quality of life.

  16. Study regarding seat’s rigidity during rear end collisions using a MADYMO occupant model

    Science.gov (United States)

    Ionut Radu, Alexandru; Cofaru, Corneliu; Tolea, Bogan; Popescu, Mihaela

    2017-10-01

    The aim of this paper is to study the effects of different front occupant backseat’s rigidities in the case of a rear end collision using a multibody virtual model of an occupant. Simulation will be conducted in PC Crash, the most common accident reconstruction software using a MADYMO multibody occupant to simulate kinematics and dynamic of the passenger. Different backseat torques will be used to see how this will influence the acceleration in the head and torso of the occupant. Also, a real crash test is made to analyze the kinematics of the occupant. We believe that the softer seat’s rigidity will reduce not only the head’s acceleration but also reduces the effect of „whiplash” upon the neck due to the fact that the backseat will rotate backwards increasing its displacement and absorb some of the energy generated by the collision. Although a softer seat could reduce the head’s acceleration, a broken seat will increase it due to the fact that the impact of the backseat with the vehicle’s rear seats will generate a second collision. So, in order to achieve a lower acceleration, a controlled torque is recommended and a controlled angular displacement of the backseat is to be used.

  17. Factors influencing the occupational injuries of physical therapists in Taiwan: A hierarchical linear model approach.

    Science.gov (United States)

    Tao, Yu-Hui; Wu, Yu-Lung; Huang, Wan-Yun

    2017-01-01

    The evidence literature suggests that physical therapy practitioners are subjected to a high probability of acquiring work-related injuries, but only a few studies have specifically investigated Taiwanese physical therapy practitioners. This study was conducted to determine the relationships among individual and group hospital-level factors that contribute to the medical expenses for the occupational injuries of physical therapy practitioners in Taiwan. Physical therapy practitioners in Taiwan with occupational injuries were selected from the 2013 National Health Insurance Research Databases (NHIRD). The age, gender, job title, hospitals attributes, and outpatient data of physical therapy practitioners who sustained an occupational injury in 2013 were obtained with SAS 9.3. SPSS 20.0 and HLM 7.01 were used to conduct descriptive and hierarchical linear model analyses, respectively. The job title of physical therapy practitioners at the individual level and the hospital type at the group level exert positive effects on per person medical expenses. Hospital hierarchy moderates the individual-level relationships of age and job title with the per person medical expenses. Considering that age, job title, and hospital hierarchy affect medical expenses for the occupational injuries of physical therapy practitioners, we suggest strengthening related safety education and training and elevating the self-awareness of the risk of occupational injuries of physical therapy practitioners to reduce and prevent the occurrence of such injuries.

  18. Stressors in Atopic Dermatitis.

    Science.gov (United States)

    Barilla, Steven; Felix, Kayla; Jorizzo, Joseph L

    2017-01-01

    As with other inflammatory skin disorders, atopic dermatitis has a tendency to cause stress and also be exacerbated by it. Patients with atopic dermatitis have several disease-associated stressors, some of which include physical discomfort due to itching and altered appearance due to flare-ups. These stressors have been shown to effect patients psychosocially by altering sleep patterns, decreasing self-esteem and interfering with interpersonal relationships. In combination with its direct effect on patients, atopic dermatitis also causes stress for parents and caregivers. Studies suggest that atopic dermatitis is strongly correlated with co-sleeping habits, which can negatively impact the health and mood of parents or caregivers. It has also been reported to interfere with the formation of a strong mother-child relationship. In order to optimize treatment for patients with atopic dermatitis, it is important to note the impact that it has on quality of life. By implementing patient counseling, sleep-targeted therapies, and the use of quality of life (QoL) indices, atopic dermatitis patients and caregivers have the potential to experience greater satisfaction with treatment.

  19. Occupational stress among dentists

    DEFF Research Database (Denmark)

    Moore, Rod

    2011-01-01

    Dentists report a high degree of occupational stress.(Cooper, Mallinger, and Kahn, 1978;Coster, Carstens, and Harris, 1987;DiMatteo, Shugars, and Hays, 1993;Hakeberg et al., 1992;Möller and Spangenberg, 1996;Moore, 2000;Myers and Myers, 2004;O'Shea, Corah, and Ayer, 1984) This chapter reviews...... the literature of studies that elaborate on the circumstances of occupational stress of dentists. These will include the frequency of occurrence of occupational stress among dentists in several countries, frequency and intensity of identified stressors specific to dentistry, as well as the consequences...... of this occupational stress. The literature on consequences includes effects on dentists' physical health, personal and occupational performance, including "burnout" phenomena, as well as topics of alcohol or substance abuse and reports of suicidal behaviour among dentists. One specific and less conventionally...

  20. Occupational Therapy and Video Modeling for Children with Autism

    Science.gov (United States)

    Becker, Emily Ann; Watry-Christian, Meghan; Simmons, Amanda; Van Eperen, Ashleigh

    2016-01-01

    This review explores the evidence in support of using video modeling for teaching children with autism. The process of implementing video modeling, the use of various perspectives, and a wide range of target skills are addressed. Additionally, several helpful clinician resources including handheld device applications, books, and websites are…

  1. Predicted and actual indoor environmental quality: Verification of occupants' behaviour models in residential buildings

    DEFF Research Database (Denmark)

    Andersen, Rune Korsholm; Fabi, Valentina; Corgnati, Stefano P.

    2016-01-01

    with the building controls (windows, thermostats, solar shading etc.). During the last decade, studies about stochastic models of occupants' behaviour in relation to control of the indoor environment have been published. Often the overall aim of these models is to enable more reliable predictions of building...... performance using building energy performance simulations (BEPS). However, the validity of these models has only been sparsely tested. In this paper, stochastic models of occupants' behaviour from literature were tested against measurements in five apartments. In a monitoring campaign, measurements of indoor....... However, comparisons of the average stochastic predictions with the measured temperatures, relative humidity and CO2 concentrations revealed that the models did not predict the actual indoor environmental conditions well....

  2. A novel modeling tool with multi-stressor functionality for organic contaminant transport and fate in the Baltic Sea

    Energy Technology Data Exchange (ETDEWEB)

    Undeman, E., E-mail: emma.undeman@itm.su.se [Baltic Nest Institute, Baltic Sea Centre, Stockholm University, 10691 Stockholm (Sweden); Department of Applied Environmental Science, Stockholm University, 11418 Stockholm (Sweden); Gustafsson, E., E-mail: erik.gustafsson@su.se [Baltic Nest Institute, Baltic Sea Centre, Stockholm University, 10691 Stockholm (Sweden); Gustafsson, B.G., E-mail: bo.gustafsson@su.se [Baltic Nest Institute, Baltic Sea Centre, Stockholm University, 10691 Stockholm (Sweden)

    2014-11-01

    The coupled physical–biogeochemical model BALTSEM, previously used to assess nutrient/carbon cycles and eutrophication in the Baltic Sea, has been expanded to include algorithms for calculations of organic contaminant environmental transport and fate. This novel model version (BALTSEM-POP) is evaluated for polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) and hexachlorobenzene (HCB) in Baltic Sea surface water and sediment. Modeled dissolved concentrations are usually within a factor of 2–4 of observed concentrations, however with larger deviations for furans. Calculated concentrations in particulate organic matter are less accurate (within factors of 1–700), likely due to errors in estimated pelagic biomass, particulate matter–water partitioning, and large natural variability in field data. Concentrations in sediments are usually predicted within a factor of 6. The good performance of the model illustrates its usefulness for exploration of contaminant fate in response to variations in nutrient input and climatic conditions in the Baltic Sea marine environment. - Highlights: • A new model for organic chemical transport and fate in the Baltic Sea is presented. • Physical and biogeochemical processes are linked to organic contaminant transport. • The model is evaluated for PCBs, HCB and PCDD/Fs. • The model can predict dissolved concentrations within a factor of ca 2–4. • Predictions for concentrations in particulate matter and sediment are less accurate.

  3. Statistical Modeling of Occupational Exposure to Polycyclic Aromatic Hydrocarbons Using OSHA Data.

    Science.gov (United States)

    Lee, Derrick G; Lavoué, Jérôme; Spinelli, John J; Burstyn, Igor

    2015-01-01

    Polycyclic aromatic hydrocarbons (PAHs) are a group of pollutants with multiple variants classified as carcinogenic. The Occupational Safety and Health Administration (OSHA) provided access to two PAH exposure databanks of United States workplace compliance testing data collected between 1979 and 2010. Mixed-effects logistic models were used to predict the exceedance fraction (EF), i.e., the probability of exceeding OSHA's Permissible Exposure Limit (PEL = 0.2 mg/m3) for PAHs based on industry and occupation. Measurements of coal tar pitch volatiles were used as a surrogate for PAHs. Time, databank, occupation, and industry were included as fixed-effects while an identifier for the compliance inspection number was included as a random effect. Analyses involved 2,509 full-shift personal measurements. Results showed that the majority of industries had an estimated EF < 0.5, although several industries, including Standardized Industry Classification codes 1623 (Water, Sewer, Pipeline, and Communication and Powerline Construction), 1711 (Plumbing, Heating, and Air-Conditioning), 2824 (Manmade Organic Fibres), 3496 (Misc. Fabricated Wire products), and 5812 (Eating Places), and Major group's 13 (Oil and Gas Extraction) and 30 (Rubber and Miscellaneous Plastic Products), were estimated to have more than an 80% likelihood of exceeding the PEL. There was an inverse temporal trend of exceeding the PEL, with lower risk in most recent years, albeit not statistically significant. Similar results were shown when incorporating occupation, but varied depending on the occupation as the majority of industries predicted at the administrative level, e.g., managers, had an estimated EF < 0.5 while at the minimally skilled/laborer level there was a substantial increase in the estimated EF. These statistical models allow the prediction of PAH exposure risk through individual occupational histories and will be used to create a job-exposure matrix for use in a population-based case

  4. Dynamic modeling of presence of occupants using inhomogeneous Markov chains

    DEFF Research Database (Denmark)

    Andersen, Philip Hvidthøft Delff; Iversen, Anne; Madsen, Henrik

    2014-01-01

    on time of day, and by use of a filter of the observations it is able to capture per-employee sequence dynamics. Simulations using this method are compared with simulations using homogeneous Markov chains and show far better ability to reproduce key properties of the data. The method is based...... on inhomogeneous Markov chains with where the transition probabilities are estimated using generalized linear models with polynomials, B-splines, and a filter of passed observations as inputs. For treating the dispersion of the data series, a hierarchical model structure is used where one model is for low presence...

  5. A goodness-of-fit test for occupancy models with correlated within-season revisits

    Science.gov (United States)

    Wright, Wilson; Irvine, Kathryn M.; Rodhouse, Thomas J.

    2016-01-01

    Occupancy modeling is important for exploring species distribution patterns and for conservation monitoring. Within this framework, explicit attention is given to species detection probabilities estimated from replicate surveys to sample units. A central assumption is that replicate surveys are independent Bernoulli trials, but this assumption becomes untenable when ecologists serially deploy remote cameras and acoustic recording devices over days and weeks to survey rare and elusive animals. Proposed solutions involve modifying the detection-level component of the model (e.g., first-order Markov covariate). Evaluating whether a model sufficiently accounts for correlation is imperative, but clear guidance for practitioners is lacking. Currently, an omnibus goodnessof- fit test using a chi-square discrepancy measure on unique detection histories is available for occupancy models (MacKenzie and Bailey, Journal of Agricultural, Biological, and Environmental Statistics, 9, 2004, 300; hereafter, MacKenzie– Bailey test). We propose a join count summary measure adapted from spatial statistics to directly assess correlation after fitting a model. We motivate our work with a dataset of multinight bat call recordings from a pilot study for the North American Bat Monitoring Program. We found in simulations that our join count test was more reliable than the MacKenzie–Bailey test for detecting inadequacy of a model that assumed independence, particularly when serial correlation was low to moderate. A model that included a Markov-structured detection-level covariate produced unbiased occupancy estimates except in the presence of strong serial correlation and a revisit design consisting only of temporal replicates. When applied to two common bat species, our approach illustrates that sophisticated models do not guarantee adequate fit to real data, underscoring the importance of model assessment. Our join count test provides a widely applicable goodness-of-fit test and

  6. Uncertainties in neural network model based on carbon dioxide concentration for occupancy estimation

    Energy Technology Data Exchange (ETDEWEB)

    Alam, Azimil Gani; Rahman, Haolia; Kim, Jung-Kyung; Han, Hwataik [Kookmin University, Seoul (Korea, Republic of)

    2017-05-15

    Demand control ventilation is employed to save energy by adjusting airflow rate according to the ventilation load of a building. This paper investigates a method for occupancy estimation by using a dynamic neural network model based on carbon dioxide concentration in an occupied zone. The method can be applied to most commercial and residential buildings where human effluents to be ventilated. An indoor simulation program CONTAMW is used to generate indoor CO{sub 2} data corresponding to various occupancy schedules and airflow patterns to train neural network models. Coefficients of variation are obtained depending on the complexities of the physical parameters as well as the system parameters of neural networks, such as the numbers of hidden neurons and tapped delay lines. We intend to identify the uncertainties caused by the model parameters themselves, by excluding uncertainties in input data inherent in measurement. Our results show estimation accuracy is highly influenced by the frequency of occupancy variation but not significantly influenced by fluctuation in the airflow rate. Furthermore, we discuss the applicability and validity of the present method based on passive environmental conditions for estimating occupancy in a room from the viewpoint of demand control ventilation applications.

  7. Efficient occupancy model-fitting for extensive citizen-science data

    Science.gov (United States)

    Morgan, Byron J. T.; Freeman, Stephen N.; Ridout, Martin S.; Brereton, Tom M.; Fox, Richard; Powney, Gary D.; Roy, David B.

    2017-01-01

    Appropriate large-scale citizen-science data present important new opportunities for biodiversity modelling, due in part to the wide spatial coverage of information. Recently proposed occupancy modelling approaches naturally incorporate random effects in order to account for annual variation in the composition of sites surveyed. In turn this leads to Bayesian analysis and model fitting, which are typically extremely time consuming. Motivated by presence-only records of occurrence from the UK Butterflies for the New Millennium data base, we present an alternative approach, in which site variation is described in a standard way through logistic regression on relevant environmental covariates. This allows efficient occupancy model-fitting using classical inference, which is easily achieved using standard computers. This is especially important when models need to be fitted each year, typically for many different species, as with British butterflies for example. Using both real and simulated data we demonstrate that the two approaches, with and without random effects, can result in similar conclusions regarding trends. There are many advantages to classical model-fitting, including the ability to compare a range of alternative models, identify appropriate covariates and assess model fit, using standard tools of maximum likelihood. In addition, modelling in terms of covariates provides opportunities for understanding the ecological processes that are in operation. We show that there is even greater potential; the classical approach allows us to construct regional indices simply, which indicate how changes in occupancy typically vary over a species’ range. In addition we are also able to construct dynamic occupancy maps, which provide a novel, modern tool for examining temporal changes in species distribution. These new developments may be applied to a wide range of taxa, and are valuable at a time of climate change. They also have the potential to motivate citizen

  8. Meta-modeling of occupancy variables and analysis of their impact on energy outcomes of office buildings

    International Nuclear Information System (INIS)

    Wang, Qinpeng; Augenbroe, Godfried; Kim, Ji-Hyun; Gu, Li

    2016-01-01

    Highlights: • A meta-analysis framework for a stochastic characterization of occupancy variables. • Sensitivity ranking of occupancy variability against all other sources of uncertainty. • Sensitivity of occupant presence for building energy consumption is low. • Accurate mean knowledge is sufficient for predicting building energy consumption. • Prediction of peak demand behavior requires stochastic occupancy modeling. - Abstract: Occupants interact with buildings in various ways via their presence (passive effects) and control actions (active effects). Therefore, understanding the influence of occupants is essential if we are to evaluate the performance of a building. In this paper, we model the mean profiles and variability of occupancy variables (presence and actions) separately. We will use a multi-variate Gaussian distribution to generate mean profiles of occupancy variables, while the variability will be represented by a multi-dimensional time series model, within a framework for a meta-analysis that synthesizes occupancy data gathered from a pool of buildings. We then discuss variants of occupancy models with respect to various outcomes of interest such as HVAC energy consumption and peak demand behavior via a sensitivity analysis. Results show that our approach is able to generate stochastic occupancy profiles, requiring minimum additional input from the energy modeler other than standard diversity profiles. Along with the meta-analysis, we enable the generalization of previous research results and statistical inferences to choose occupancy variables for future buildings. The sensitivity analysis shows that for aggregated building energy consumption, occupant presence has a smaller impact compared to lighting and appliance usage. Specifically, being accumulatively 55% wrong with regard to presence, only translates to 2% error in aggregated cooling energy in July and 3.6% error in heating energy in January. Such a finding redirects focus to the

  9. Two-species occupancy modeling accounting for species misidentification and nondetection

    Science.gov (United States)

    Chambert, Thierry; Grant, Evan H. Campbell; Miller, David A. W.; Nichols, James; Mulder, Kevin P.; Brand, Adrianne B,

    2018-01-01

    1. In occupancy studies, species misidentification can lead to false positive detections, which can cause severe estimator biases. Currently, all models that account for false positive errors only consider omnibus sources of false detections and are limited to single species occupancy. 2. However, false detections for a given species often occur because of the misidentification with another, closely-related species. To exploit this explicit source of false positive detection error, we develop a two-species occupancy model that accounts for misidentifications between two species of interest. As with other false positive models, identifiability is greatly improved by the availability of unambiguous detections at a subset of site-occasions. Here, we consider the case where some of the field observations can be confirmed using laboratory or other independent identification methods (“confirmatory data”). 3. We performed three simulation studies to (1) assess the model’s performance under various realistic scenarios, (2) investigate the influence of the proportion of confirmatory data on estimator accuracy, and (3) compare the performance of this two-species model with that of the single-species false positive model. The model shows good performance under all scenarios, even when only small proportions of detections are confirmed (e.g., 5%). It also clearly outperforms the single-species model.

  10. Occupant-vehicle dynamics and the role of the internal model

    Science.gov (United States)

    Cole, David J.

    2018-05-01

    With the increasing need to reduce time and cost of vehicle development there is increasing advantage in simulating mathematically the dynamic interaction of a vehicle and its occupant. The larger design space arising from the introduction of automated vehicles further increases the potential advantage. The aim of the paper is to outline the role of the internal model hypothesis in understanding and modelling occupant-vehicle dynamics, specifically the dynamics associated with direction and speed control of the vehicle. The internal model is the driver's or passenger's understanding of the vehicle dynamics and is thought to be employed in the perception, cognition and action processes of the brain. The internal model aids the estimation of the states of the vehicle from noisy sensory measurements. It can also be used to optimise cognitive control action by predicting the consequence of the action; thus model predictive control (MPC) theory provides a foundation for modelling the cognition process. The stretch reflex of the neuromuscular system also makes use of the prediction of the internal model. Extensions to the MPC approach are described which account for: interaction with an automated vehicle; robust control; intermittent control; and cognitive workload. Further work to extend understanding of occupant-vehicle dynamic interaction is outlined. This paper is based on a keynote presentation given by the author to the 13th International Symposium on Advanced Vehicle Control (AVEC) conference held in Munich, September 2016.

  11. Capturing the response of Clostridium acetobutylicum to chemical stressors using a regulated genome-scale metabolic model

    International Nuclear Information System (INIS)

    Dash, Satyakam; Mueller, Thomas J.; Venkataramanan, Keerthi P.; Papoutsakis, Eleftherios T.; Maranas, Costas D.

    2014-01-01

    Clostridia are anaerobic Gram-positive Firmicutes containing broad and flexible systems for substrate utilization, which have been used successfully to produce a range of industrial compounds. Clostridium acetobutylicum has been used to produce butanol on an industrial scale through acetone-butanol-ethanol (ABE) fermentation. A genome-scale metabolic (GSM) model is a powerful tool for understanding the metabolic capacities of an organism and developing metabolic engineering strategies for strain development. The integration of stress related specific transcriptomics information with the GSM model provides opportunities for elucidating the focal points of regulation

  12. Climate change and other stressors change modeled population size and hybridization potential for San Joaquin kit fox

    Science.gov (United States)

    The San Joaquin kit fox was once widely distributed across the southern San Joaquin Valley, but agriculture and development have replaced much of the endangered subspecies’ habitat. We modeled impacts of climate change, land-use change, and rodenticide exposure on kit fox p...

  13. Hemodialysis: stressors and coping strategies.

    Science.gov (United States)

    Ahmad, Muayyad M; Al Nazly, Eman K

    2015-01-01

    End-stage renal disease (ESRD) is an irreversible and life-threatening condition. In Jordan, the number of ESRD patients treated with hemodialysis is on the rise. Identifying stressors and coping strategies used by patients with ESRD may help nurses and health care providers to gain a clearer understanding of the condition of these patients and thus institute effective care planning. The purpose of this study was to identify stressors perceived by Jordanian patients on hemodialysis, and the coping strategies used by them. A convenience sample of 131 Jordanian men and women was recruited from outpatients' dialysis units in four hospitals. Stressors perceived by participants on hemodialysis and the coping strategies were measured using Hemodialysis Stressor Scale, and Ways of Coping Scale-Revised. Findings showed that patients on hemodialysis psychosocial stressors scores mean was higher than the physiological stressors mean. Positive reappraisal coping strategy had the highest mean among the coping strategies and the lowest mean was accepting responsibility. Attention should be focused towards the psychosocial stressors of patients on hemodialysis and also helping patients utilize the coping strategies that help to alleviate the stressors. The most used coping strategy was positive reappraisal strategy which includes faith and prayer.

  14. Impact of Deployment-Related Sexual Stressors on Psychiatric Symptoms After Accounting for Predeployment Stressors: Findings From a U.S. National Guard Cohort.

    Science.gov (United States)

    McCallum, Ethan B; Murdoch, Maureen; Erbes, Christopher R; Arbisi, Paul; Polusny, Melissa A

    2015-08-01

    This study used a longitudinal research design to examine the impact of predeployment stressors and deployment-related sexual stressors on self-reported psychiatric symptoms of U.S. National Guard soldiers returning from deployments to Iraq or Afghanistan. Prior to deployment, participants completed measures of depression and posttraumatic stress symptoms, along with an inventory of predeployment stressor experiences. At 3-months postdeployment, participants (468 men, 60 women) again completed self-report measures of psychiatric symptoms, along with an inventory of sexual stressors experienced during deployment. We compared a cross-sectional model of sexual stressors' impact on psychiatric symptoms, in which only postdeployment reports were considered, to a longitudinal model in which we adjusted for participants' predeployment stressors and psychiatric symptoms. No participants reported sexual assault during deployment, though sexual harassment was common. The cross-sectional model suggested that deployment-related sexual stressors were significantly associated with postdeployment depression (R(2) = .11) and posttraumatic stress symptoms (R(2) = .10). Once predeployment factors were taken into consideration, however, sexual stressors were no longer significant. The results did not support the notion of lasting negative impact for low-level sexual stressors (e.g., sexual harassment) during deployment after predeployment stressors are accounted for. Future studies of sexual stressors should consider longitudinal designs. © 2015 International Society for Traumatic Stress Studies.

  15. The Ambivalence of Challenge Stressors: Time Pressure Associated with Both Negative and Positive Well-Being

    Science.gov (United States)

    Widmer, Pascale S.; Semmer, Norbert K.; Kalin, Wolfgang; Jacobshagen, Nicola; Meier, Laurenz L.

    2012-01-01

    According to the challenge-hindrance model, challenge stressors contain both stressful and challenging aspects, hindrance stressors only stressful aspects. Typically, negative outcomes of challenge stressors refer to well-being (strain), positive outcomes to so-called work outcomes (e.g., productivity, intention to quit). As both effects occur…

  16. Toward a Better Understanding of the Effects of Hindrance and Challenge Stressors on Work Behavior

    Science.gov (United States)

    Webster, Jennica R.; Beehr, Terry A.; Christiansen, Neil D.

    2010-01-01

    This study investigated the processes whereby hindrance and challenge stressors may affect work behavior. Three mechanisms were examined to explain the differential effects these stressors have demonstrated: job satisfaction, strains, and work self-efficacy. A model is proposed in which both types of stressors will result in increases in strains,…

  17. An ecological process model of female sex offending: the role of victimization, psychological distress, and life stressors.

    Science.gov (United States)

    DeCou, Christopher R; Cole, Trevor T; Rowland, Sarah E; Kaplan, Stephanie P; Lynch, Shannon M

    2015-06-01

    Female sex offenders may be implicated in up to one fifth of all sex crimes committed in the United States. Despite previous research findings that suggest unique patterns of offending among female sex offenders, limited empirical research has investigated the motivations and processes involved. The present study qualitatively examined female sex offenders' offense-related experiences and characterized the internal and external factors that contributed to offending. Semi-structured interviews with 24 female sex offenders were analyzed by a team of coders with limited exposure to the existing literature using grounded theory analysis. A conceptual framework emerged representing distinctive processes for solo- and co-offending, contextualized within ecological layers of social and environmental influence. This model extends previous work by offering an example of nested vulnerabilities proximal to female sexual offending. Implications for future research, prevention, and treatment are discussed. © The Author(s) 2014.

  18. Measuring and modelling occupancy time in NHS continuing healthcare

    Directory of Open Access Journals (Sweden)

    Millard Peter H

    2011-06-01

    Full Text Available Abstract Background Due to increasing demand and financial constraints, NHS continuing healthcare systems seek to find better ways of forecasting demand and budgeting for care. This paper investigates two areas of concern, namely, how long existing patients stay in service and the number of patients that are likely to be still in care after a period of time. Methods An anonymised dataset containing information for all funded admissions to placement and home care in the NHS continuing healthcare system was provided by 26 (out of 31 London primary care trusts. The data related to 11289 patients staying in placement and home care between 1 April 2005 and 31 May 2008 were first analysed. Using a methodology based on length of stay (LoS modelling, we captured the distribution of LoS of patients to estimate the probability of a patient staying in care over a period of time. Using the estimated probabilities we forecasted the number of patients that are likely to be still in care after a period of time (e.g. monthly. Results We noticed that within the NHS continuing healthcare system there are three main categories of patients. Some patients are discharged after a short stay (few days, some others staying for few months and the third category of patients staying for a long period of time (years. Some variations in proportions of discharge and transition between types of care as well as between care groups (e.g. palliative, functional mental health were observed. A close agreement of the observed and the expected numbers of patients suggests a good prediction model. Conclusions The model was tested for care groups within the NHS continuing healthcare system in London to support Primary Care Trusts in budget planning and improve their responsiveness to meet the increasing demand under limited availability of resources. Its applicability can be extended to other types of care, such as hospital care and re-ablement. Further work will be geared towards

  19. Relationship of occupational and non-occupational stress with smoking in automotive industry workers.

    Science.gov (United States)

    Hassani, Somayeh; Yazdanparast, Taraneh; Seyedmehdi, Seyed Mohammad; Ghaffari, Mostafa; Attarchi, Mirsaeed; Bahadori, Baharak

    2014-01-01

    Tobacco use is the second cause of death and first cause of preventable mortality worldwide. Smoking in the workplace is particularly concerning. Smoking-free workplaces decrease the risk of exposure of non-smoking personnel to cigarette smoke. Recent studies have mostly focused on the effect of daily or non-occupational stressors (in comparison with occupational stress) on prevalence of smoking. Occupational stress is often evaluated in workplaces for smoking cessation or control programs, but the role of non-occupational stressors is often disregarded in this respect. This cross-sectional study was conducted in an automobile manufacturing company. The response of automotive industry workers to parts of the validated, reliable, Farsi version of Musculoskeletal Intervention Center (MUSIC)-Norrtalje questionnaire was evaluated. A total of 3,536 factory workers participated in this study. Data were analyzed using SPSS and P<0.05 was considered statistically significant. The correlation of smoking with demographic factors, occupational stressors and life events was evaluated. The results of logistic regression analysis showed that even after adjusting for the confounding factors, cigarette smoking was significantly correlated with age, sex, level of education, job control and life events (P<0.05). The results showed that of occupational and non-occupational stressors, only job control was correlated with cigarette smoking. Non-occupational stressors had greater effect on cigarette smoking. Consideration of both non-occupational and occupational stressors can enhance the success of smoking control programs. On the other hand, a combination of smoking control and stress (occupational and non-occupational) control programs can be more effective than smoking cessation interventions alone.

  20. Modelling and forecasting occupational accidents of different severity levels in Spain

    International Nuclear Information System (INIS)

    Carmen Carnero, Maria; Jose Pedregal, Diego

    2010-01-01

    The control of accidents at the work place is a critical issue all over the world. The consequences of occupational accidents in terms of costs for the company in which the accidents take place is only one minor matter, being the social impact and the loss of human life the most controversial effects of this important problem. The methods used to forecast future evolution of accidents are often limited to trend estimations and projections, being the scientific literature on this topic rather scarce. This paper aims at showing and predicting the evolution of Spanish occupational accidents of different levels of severity, allowing the evaluation of the influence that preventive actions carried out by public administrations or private companies may have over the number of occupational accidents. Though some contributions may be found on this topic for Spain, this paper is the first contribution that forecast occupational accidents for different levels of severity using Multivariate Unobserved Components models developed in a State Space framework extended to deal with the irregular sampling interval of the data. Data from 1998 to 2009 have been used to test the efficacy of the forecasting system.

  1. Concept Analysis of Occupational Therapy Handling in the Children with Cerebral Palsy: A Hybrid Model

    Directory of Open Access Journals (Sweden)

    Hamid Dalvand

    2015-07-01

    Full Text Available Objective: This study aimed to analyze the concept of occupational therapy handling in the children with cerebral palsy from the perspective of occupational therapy instructors and clinicians in Iran. Materials & Methods: In this qualitative study, using hybrid model to clarify the concept of handling through three phases. For the theoretical phase, attributes of handling were recognized through a review of the literature (until February 2014, and six in-depth semi - structured interviews, two observations and one panel of experts were conducted for the fieldwork to develop attributes from the data and to verify those identified from the literature review. In the third phase attributes and final analysis of handling were extracted from the first and second phase. Results: The results were classified in five main categories that were identified as: (1 care of child, (2 management of treatment, (3 manual techniques, (4 education of activities of daily living (ADL, and (5 lifting and carrying. Core attributes of handling include "control, safety, transfer and positioning". Conclusion: It seems that the results of this study may help in clarifying the concept of handling in children with CP. In addition, by identifying the process, barriers and facilitative factors, and the concept of handling, occupational therapy instructors and therapists will be able to design and run their educational activities based on scientific findings which can provide them with the necessary conditions for education, learning and proper execution of handling in occupational therapy.

  2. Modeling Net Land Occupation of Hydropower Reservoirs in Norway for Use in Life Cycle Assessment.

    Science.gov (United States)

    Dorber, Martin; May, Roel; Verones, Francesca

    2018-02-20

    Increasing hydropower electricity production constitutes a unique opportunity to mitigate climate change impacts. However, hydropower electricity production also impacts aquatic and terrestrial biodiversity through freshwater habitat alteration, water quality degradation, and land use and land use change (LULUC). Today, no operational model exists that covers any of these cause-effect pathways within life cycle assessment (LCA). This paper contributes to the assessment of LULUC impacts of hydropower electricity production in Norway in LCA. We quantified the inundated land area associated with 107 hydropower reservoirs with remote sensing data and related it to yearly electricity production. Therewith, we calculated an average net land occupation of 0.027 m 2 ·yr/kWh of Norwegian storage hydropower plants for the life cycle inventory. Further, we calculated an adjusted average land occupation of 0.007 m 2 ·yr/kWh, accounting for an underestimation of water area in the performed maximum likelihood classification. The calculated land occupation values are the basis to support the development of methods for assessing the land occupation impacts of hydropower on biodiversity in LCA at a damage level.

  3. A respiratory model for uranium aluminide based on occupational data

    International Nuclear Information System (INIS)

    Leggett, R W; Eckerman, K F; Jr, J D Boice

    2005-01-01

    As part of an epidemiological study, doses from intake of radionuclides were estimated for workers employed during a 52-year period at the Rocketdyne/Atomics International facility in California. The facility was involved in a variety of research programmes, including nuclear fuel fabrication, spent nuclear fuel decladding, and reactor operation and disassembly. Most of the documented intakes involved inhalation of enriched uranium (U), fission products, or plutonium (Pu). Highest doses were estimated for a group of workers exposed to airborne uranium aluminide (UAl x ) during the fabrication of reactor fuel plates. Much of the exposure to UAl x occurred early in the fuel fabrication programme, before it was recognised that intake and lung retention were being underestimated from urinary data due to an unexpected delayed dissolution of the inhaled material. In workers who had been removed from exposure, the rate of urinary excretion of U increased for a few months, peaked, and then declined at a rate consistent with moderately soluble material. This pattern differs markedly from the monotonically decreasing absorption rates represented by the default absorption types in the Human Respiratory Tract Model (HRTM) of the International Commission on Radiological Protection (ICRP). This paper summarises the findings on the behaviour of UAl x in these workers and describes material-specific parameter values of the HRTM based on this information

  4. Predictive models for the assessment of occupational exposure to chemicals: A new challenge for employers

    Directory of Open Access Journals (Sweden)

    Jan Piotr Gromiec

    2013-10-01

    Full Text Available Employers are obliged to carry out and document the risk associated with the use of chemical substances. The best but the most expensive method is to measure workplace concentrations of chemicals. At present no "measureless" method for risk assessment is available in Poland, but predictive models for such assessments have been developed in some countries. The purpose of this work is to review and evaluate the applicability of selected predictive methods for assessing occupational inhalation exposure and related risk to check the compliance with Occupational Exposure Limits (OELs, as well as the compliance with REACH obligations. Based on the literature data HSE COSHH Essentials, EASE, ECETOC TRA, Stoffenmanager, and EMKG-Expo-Tool were evaluated. The data on validation of predictive models were also examined. It seems that predictive models may be used as a useful method for Tier 1 assessment of occupational exposure by inhalation. Since the levels of exposure are frequently overestimated, they should be considered as "rational worst cases" for selection of proper control measures. Bearing in mind that the number of available exposure scenarios and PROC categories is limited, further validation by field surveys is highly recommended. Predictive models may serve as a good tool for preliminary risk assessment and selection of the most appropriate risk control measures in Polish small and medium size enterprises (SMEs providing that they are available in the Polish language. This also requires an extensive training of their future users. Med Pr 2013;64(5:699–716

  5. TREXMO: A Translation Tool to Support the Use of Regulatory Occupational Exposure Models.

    Science.gov (United States)

    Savic, Nenad; Racordon, Dimitri; Buchs, Didier; Gasic, Bojan; Vernez, David

    2016-10-01

    Occupational exposure models vary significantly in their complexity, purpose, and the level of expertise required from the user. Different parameters in the same model may lead to different exposure estimates for the same exposure situation. This paper presents a tool developed to deal with this concern-TREXMO or TRanslation of EXposure MOdels. TREXMO integrates six commonly used occupational exposure models, namely, ART v.1.5, STOFFENMANAGER(®) v.5.1, ECETOC TRA v.3, MEASE v.1.02.01, EMKG-EXPO-TOOL, and EASE v.2.0. By enabling a semi-automatic translation between the parameters of these six models, TREXMO facilitates their simultaneous use. For a given exposure situation, defined by a set of parameters in one of the models, TREXMO provides the user with the most appropriate parameters to use in the other exposure models. Results showed that, once an exposure situation and parameters were set in ART, TREXMO reduced the number of possible outcomes in the other models by 1-4 orders of magnitude. The tool should manage to reduce the uncertain entry or selection of parameters in the six models, improve between-user reliability, and reduce the time required for running several models for a given exposure situation. In addition to these advantages, registrants of chemicals and authorities should benefit from more reliable exposure estimates for the risk characterization of dangerous chemicals under Regulation, Evaluation, Authorisation and restriction of CHemicals (REACH). © The Author 2016. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  6. Evaluating Performance of Safety Management and Occupational Health Using Total Quality Safety Management Model (TQSM

    Directory of Open Access Journals (Sweden)

    E Mohammadfam

    2015-11-01

    Full Text Available Introduction: All organizations, whether public or private, necessitate performance evaluation systems in regard with growth, stability, and development in the competitive fields. One of the existing models for performance evaluation of occupational health and safety management is Total Quality Safety Management model (TQSM. Therefore, the present study aimed to evaluate performance of safety management and occupational health utilizing TQSM model. Methods: In this descriptive-analytic study, the population consisted of 16 individuals, including managers, supervisors, and members of technical protection and work health committee. Then the participants were asked to respond to TQSM questionnaire before and after the implementation of Occupational Health & Safety Advisory Services 18001 (OHSAS18001. Ultimately, the level of each program as well as the TQSM status were determined before and after the implementation of OHSAS18001. Results: The study results showed that the scores obtained by the company before OHSAS 18001’s implementation, was 43.7 out of 312. After implementing OHSAS 18001 in the company and receiving the related certificate, the total score of safety program that company could obtain was 127.12 out of 312 demonstrating a rise of 83.42 scores (26.8%. The paired t-test revealed that mean difference of TQSM scores before and after OHSAS 18001 implementation was proved to be significant (p> 0.05. Conclusion: The study findings demonstrated that TQSM can be regarded as an appropriate model in order to monitor the performance of safety management system and occupational health, since it possesses the ability to quantitatively evaluate the system performance.

  7. Evaluating multi-level models to test occupancy state responses of Plethodontid salamanders

    Science.gov (United States)

    Kroll, Andrew J.; Garcia, Tiffany S.; Jones, Jay E.; Dugger, Catherine; Murden, Blake; Johnson, Josh; Peerman, Summer; Brintz, Ben; Rochelle, Michael

    2015-01-01

    Plethodontid salamanders are diverse and widely distributed taxa and play critical roles in ecosystem processes. Due to salamander use of structurally complex habitats, and because only a portion of a population is available for sampling, evaluation of sampling designs and estimators is critical to provide strong inference about Plethodontid ecology and responses to conservation and management activities. We conducted a simulation study to evaluate the effectiveness of multi-scale and hierarchical single-scale occupancy models in the context of a Before-After Control-Impact (BACI) experimental design with multiple levels of sampling. Also, we fit the hierarchical single-scale model to empirical data collected for Oregon slender and Ensatina salamanders across two years on 66 forest stands in the Cascade Range, Oregon, USA. All models were fit within a Bayesian framework. Estimator precision in both models improved with increasing numbers of primary and secondary sampling units, underscoring the potential gains accrued when adding secondary sampling units. Both models showed evidence of estimator bias at low detection probabilities and low sample sizes; this problem was particularly acute for the multi-scale model. Our results suggested that sufficient sample sizes at both the primary and secondary sampling levels could ameliorate this issue. Empirical data indicated Oregon slender salamander occupancy was associated strongly with the amount of coarse woody debris (posterior mean = 0.74; SD = 0.24); Ensatina occupancy was not associated with amount of coarse woody debris (posterior mean = -0.01; SD = 0.29). Our simulation results indicate that either model is suitable for use in an experimental study of Plethodontid salamanders provided that sample sizes are sufficiently large. However, hierarchical single-scale and multi-scale models describe different processes and estimate different parameters. As a result, we recommend careful consideration of study questions

  8. Evaluating Multi-Level Models to Test Occupancy State Responses of Plethodontid Salamanders.

    Directory of Open Access Journals (Sweden)

    Andrew J Kroll

    Full Text Available Plethodontid salamanders are diverse and widely distributed taxa and play critical roles in ecosystem processes. Due to salamander use of structurally complex habitats, and because only a portion of a population is available for sampling, evaluation of sampling designs and estimators is critical to provide strong inference about Plethodontid ecology and responses to conservation and management activities. We conducted a simulation study to evaluate the effectiveness of multi-scale and hierarchical single-scale occupancy models in the context of a Before-After Control-Impact (BACI experimental design with multiple levels of sampling. Also, we fit the hierarchical single-scale model to empirical data collected for Oregon slender and Ensatina salamanders across two years on 66 forest stands in the Cascade Range, Oregon, USA. All models were fit within a Bayesian framework. Estimator precision in both models improved with increasing numbers of primary and secondary sampling units, underscoring the potential gains accrued when adding secondary sampling units. Both models showed evidence of estimator bias at low detection probabilities and low sample sizes; this problem was particularly acute for the multi-scale model. Our results suggested that sufficient sample sizes at both the primary and secondary sampling levels could ameliorate this issue. Empirical data indicated Oregon slender salamander occupancy was associated strongly with the amount of coarse woody debris (posterior mean = 0.74; SD = 0.24; Ensatina occupancy was not associated with amount of coarse woody debris (posterior mean = -0.01; SD = 0.29. Our simulation results indicate that either model is suitable for use in an experimental study of Plethodontid salamanders provided that sample sizes are sufficiently large. However, hierarchical single-scale and multi-scale models describe different processes and estimate different parameters. As a result, we recommend careful consideration of

  9. A longitudinal study of teachers' occupational well-being: Applying the job demands-resources model.

    Science.gov (United States)

    Dicke, Theresa; Stebner, Ferdinand; Linninger, Christina; Kunter, Mareike; Leutner, Detlev

    2018-04-01

    The job demands-resources model (JD-R model; Bakker & Demerouti, 2014) is well established in occupational research, and the proposed processes it posits have been replicated numerous times. Thus, the JD-R model provides an excellent framework for explaining the occupational well-being of beginning teachers-an occupation associated with particularly high levels of strain and consequently, high attrition rates. However, the model's assumptions have to date mostly been tested piecewise, and seldom on the basis of longitudinal models. With a series of longitudinal autoregressive SEM models (N = 1,700) we tested all assumptions of the JD-R model simultaneously in one model with an applied focus on beginning teachers. We assessed self-reports of beginning teachers at three time waves: at the beginning and end (one and a half to two years later) of their preservice period, and again, one year later. Results revealed significant direct effects of resources (self-efficacy) on engagement, of demands (classroom disturbances) on strain (emotional exhaustion), and a significant reverse path of engagement on self-efficacy. Additionally, the results showed two moderation effects: Self-efficacy buffered the demands-strain relationship, while self-efficacy also predicted engagement, especially when disturbances were high. Thus, self-efficacy in classroom management plays an important role in the teachers' stress development process, as it will, in case of high classroom disturbances, not only buffer the strain-enhancing effects, but also boost engagement. Commitment was predicted directly by emotional exhaustion and engagement, but indirectly only by self-efficacy (via engagement). Thus, we provide strong empirical support for the JD-R model. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  10. Occupancy modeling and estimation of the holiday darter species complex within the Etowah River system

    Science.gov (United States)

    Anderson, Gregory B.; Freeman, Mary C.; Hagler, Megan M.; Freeman, Byron J.

    2012-01-01

    Documenting the status of rare fishes is a crucial step in effectively managing populations and implementing regulatory mechanisms of protection. In recent years, site occupancy has become an increasingly popular metric for assessing populations, but species distribution models that do not account for imperfect detection can underestimate the proportion of sites occupied and the strength of the relationship with a hypothesized covariate. However, valid detection requires temporal or spatial replication, which is often not feasible due to logistical or budget constraints. In this study, we used a method that allowed for spatial replication during a single visit to evaluate the current status of the holiday darter species complex, Etheostoma sp. cf. E. brevirostrum, within the Etowah River system. Moreover, the modeling approach used in this study facilitated comparisons of factors influencing stream occupancy as well as species detection within sites. The results suggest that there is less habitat available for the Etowah holiday darter form (Etheostoma sp. cf. E. brevirostrum B) than for the Amicalola holiday darter form (Etheostoma sp. cf. E. brevirostrum A). Additionally, occupancy models suggest that even small decreases in forest cover within these headwater systems adversely affect holiday darter populations.

  11. Using multi-species occupancy models in structured decision making on managed lands

    Science.gov (United States)

    Sauer, John R.; Blank, Peter J.; Zipkin, Elise F.; Fallon, Jane E.; Fallon, Frederick W.

    2013-01-01

    Land managers must balance the needs of a variety of species when manipulating habitats. Structured decision making provides a systematic means of defining choices and choosing among alternative management options; implementation of a structured decision requires quantitative approaches to predicting consequences of management on the relevant species. Multi-species occupancy models provide a convenient framework for making structured decisions when the management objective is focused on a collection of species. These models use replicate survey data that are often collected on managed lands. Occupancy can be modeled for each species as a function of habitat and other environmental features, and Bayesian methods allow for estimation and prediction of collective responses of groups of species to alternative scenarios of habitat management. We provide an example of this approach using data from breeding bird surveys conducted in 2008 at the Patuxent Research Refuge in Laurel, Maryland, evaluating the effects of eliminating meadow and wetland habitats on scrub-successional and woodland-breeding bird species using summed total occupancy of species as an objective function. Removal of meadows and wetlands decreased value of an objective function based on scrub-successional species by 23.3% (95% CI: 20.3–26.5), but caused only a 2% (0.5, 3.5) increase in value of an objective function based on woodland species, documenting differential effects of elimination of meadows and wetlands on these groups of breeding birds. This approach provides a useful quantitative tool for managers interested in structured decision making.

  12. Job stressors, personality and burnout in primary school teachers.

    Science.gov (United States)

    Kokkinos, Constantinos M

    2007-03-01

    Teaching is considered a highly stressful occupation. Burnout is a negative affective response occurring as a result of chronic work stress. While the early theories of burnout focused exclusively on work-related stressors, recent research adopts a more integrative approach where both environmental and individual factors are studied. Nevertheless, such studies are scarce with teacher samples. The present cross-sectional study sought to investigate the association between burnout, personality characteristics and job stressors in primary school teachers from Cyprus. The study also investigates the relative contribution of these variables on the three facets of burnout - emotional exhaustion, depersonalization and reduced personal accomplishment. A representative sample of 447 primary school teachers participated in the study. Teachers completed measures of burnout, personality and job stressors along with demographic and professional data. Surveys were delivered by courier to schools, and were distributed at faculty meetings. Results showed that both personality and work-related stressors were associated with burnout dimensions. Neuroticism was a common predictor of all dimensions of burnout although in personal accomplishment had a different direction. Managing student misbehaviour and time constraints were found to systematically predict dimensions of burnout. Teachers' individual characteristics as well as job related stressors should be taken into consideration when studying the burnout phenomenon. The fact that each dimension of the syndrome is predicted by different variables should not remain unnoticed especially when designing and implementing intervention programmes to reduce burnout in teachers.

  13. Evaluation of Mid-Size Male Hybrid III Models for use in Spaceflight Occupant Protection Analysis

    Science.gov (United States)

    Putnam, J.; Somers, J.; Wells, J.; Newby, N.; Currie-Gregg, N.; Lawrence, C.

    2016-01-01

    Introduction: In an effort to improve occupant safety during dynamic phases of spaceflight, the National Aeronautics and Space Administration (NASA) has worked to develop occupant protection standards for future crewed spacecraft. One key aspect of these standards is the identification of injury mechanisms through anthropometric test devices (ATDs). Within this analysis, both physical and computational ATD evaluations are required to reasonably encompass the vast range of loading conditions any spaceflight crew may encounter. In this study the accuracy of publically available mid-size male HIII ATD finite element (FE) models are evaluated within applicable loading conditions against extensive sled testing performed on their physical counterparts. Methods: A series of sled tests were performed at the Wright Patterson Air force Base (WPAFB) employing variations of magnitude, duration, and impact direction to encompass the dynamic loading range for expected spaceflight. FE simulations were developed to the specifications of the test setup and driven using measured acceleration profiles. Both fast and detailed FE models of the mid-size male HIII were ran to quantify differences in their accuracy and thus assess the applicability of each within this field. Results: Preliminary results identify the dependence of model accuracy on loading direction, magnitude, and rate. Additionally the accuracy of individual response metrics are shown to vary across each model within evaluated test conditions. Causes for model inaccuracy are identified based on the observed relationships. Discussion: Computational modeling provides an essential component to ATD injury metric evaluation used to ensure the safety of future spaceflight occupants. The assessment of current ATD models lays the groundwork for how these models can be used appropriately in the future. Identification of limitations and possible paths for improvement aid in the development of these effective analysis tools.

  14. Impact of Noncaregiving-Related Stressors on Informal Caregiver Outcomes.

    Science.gov (United States)

    Austrom, Mary Guerriero; Lu, Yvonne Yueh-Feng; Perkins, Anthony J; Boustani, Malaz; Callahan, Christopher M; Hendrie, Hugh C

    2014-08-01

    Caregivers of persons with dementia are stressed. Stressors not related to care recipients' needs impact caregiver outcomes, yet are seldom reported. The purpose of this study was to report the most stressful events experienced by spouse caregivers of older adults with Alzheimer s disease during a 6-month period. 31 caregivers completed the Most Stressful Event form, Patient Health Questionnaire (PHQ-9) and the Revised Memory Behavioral Problem Checklist (R-MBPC). Fisher's exact test and two-sample t-test were used to compare Most Stressful Events between caregivers. ANOVA model tested whether the PHQ-9 and R-MBPC subscales differed by stressor. Caregivers reported no stressors 21.5% of the time, 1-2 stressors 25% of the time, and 3 stressors 53% of the time with 318 stressors reported in total. Care recipient needs (30.2%), caregiver needs (26.7%), and decision-making (16.7%) were the most frequently reported stressors. Using a mixed effects model, there were associations between the Most Stressful Events and depression (p = 0.016), mobility (p = 0.024) and caregiver issues (p = 0.009) subscales of R-MBPC. Results can be used to develop targeted intervention and support strategies for spouse caregivers experiencing non-caregiving related stressorsas well as the traditional challenges with caregiving related issues. © The Author(s) 2014.

  15. Occupational Clusters.

    Science.gov (United States)

    Pottawattamie County School System, Council Bluffs, IA.

    The 15 occupational clusters (transportation, fine arts and humanities, communications and media, personal service occupations, construction, hospitality and recreation, health occupations, marine science occupations, consumer and homemaking-related occupations, agribusiness and natural resources, environment, public service, business and office…

  16. Using occupancy models to understand the distribution of an amphibian pathogen, Batrachochytrium dendrobatidis

    Science.gov (United States)

    Adams, Michael J.; Chelgren, Nathan; Reinitz, David M.; Cole, Rebecca A.; Rachowicz, L.J.; Galvan, Stephanie; Mccreary, Brome; Pearl, Christopher A.; Bailey, Larissa L.; Bettaso, Jamie B.; Bull, Evelyn L.; Leu, Matthias

    2010-01-01

    Batrachochytrium dendrobatidis is a fungal pathogen that is receiving attention around the world for its role in amphibian declines. Study of its occurrence patterns is hampered by false negatives: the failure to detect the pathogen when it is present. Occupancy models are a useful but currently underutilized tool for analyzing detection data when the probability of detecting a species is population, was related to amphibian development stage, day of the year, elevation, and human activities. Batrachochytrium dendrobatidis was found throughout our study area but was only estimated to occur in 53.4% of 78 populations of native amphibians and 66.4% of 40 populations of nonnative Rana catesbeiana tested. We found little evidence to support any spatial hypotheses concerning the probability that the pathogen occurs in a population, but did find evidence of some taxonomic variation. We discuss the interpretation of occupancy model parameters, when, unlike a conventional occupancy application, the number of potential samples or observations is finite.

  17. The complexity of role balance: support for the Model of Juggling Occupations.

    Science.gov (United States)

    Evans, Kiah L; Millsteed, Jeannine; Richmond, Janet E; Falkmer, Marita; Falkmer, Torbjorn; Girdler, Sonya J

    2014-09-01

    This pilot study aimed to establish the appropriateness of the Model of Juggling Occupations in exploring the complex experience of role balance amongst working women with family responsibilities living in Perth, Australia. In meeting this aim, an evaluation was conducted of a case study design, where data were collected through a questionnaire, time diary, and interview. Overall role balance varied over time and across participants. Positive indicators of role balance occurred frequently in the questionnaires and time diaries, despite the interviews revealing a predominance of negative evaluations of role balance. Between-role balance was achieved through compatible role overlap, buffering, and renewal. An exploration of within-role balance factors demonstrated that occupational participation, values, interests, personal causation, and habits were related to role balance. This pilot study concluded that the Model of Juggling Occupations is an appropriate conceptual framework to explore the complex and dynamic experience of role balance amongst working women with family responsibilities. It was also confirmed that the case study design, including the questionnaire, time diary, and interview methods, is suitable for researching role balance from this perspective.

  18. AN EFFECTIVE RISK-PREVENTIVE MODEL PROPOSAL FOR OCCUPATIONAL ACCIDENTS AT SHIPYARDS

    Directory of Open Access Journals (Sweden)

    Ozge Acuner

    2016-03-01

    Full Text Available According to the statistics of occupational accidents, it is observed that the number of accidents occurred in shipbuilding industry is high and the rate of deaths and serious injuries among these accidents is higher than in other industries. However, the number of the studies to prevent these accidents in both industrial and scientific practices is considerably low. Therefore, the objective of this study is to develop an efficient risk preventive model in accordance with occupational health and safety regulations for industrial organizations. The approach proposed in this study differs from those described in the literature, because it is based on fuzzy set theory in order to cope with uncertainties on probability and severity definitions in terms of occupational health and safety. Furthermore, in this paper, risk severity is considered in terms of harm to worker, harm to environment, and harm to hardware, whereas in the literature, risk severity is generally considered solely in terms of only harm to worker. Then, risk magnitude is obtained by utilizing fuzzy inference system. The proposed approach is applied to a shipyard located in the Marmara Region in order to illustrate the applicability of the model.

  19. A novel approach to surveying sturgeon using side-scan sonar and occupancy modeling

    Science.gov (United States)

    Flowers, H. Jared; Hightower, Joseph E.

    2013-01-01

    Technological advances represent opportunities to enhance and supplement traditional fisheries sampling approaches. One example with growing importance for fisheries research is hydroacoustic technologies such as side-scan sonar. Advantages of side-scan sonar over traditional techniques include the ability to sample large areas efficiently and the potential to survey fish without physical handling-important for species of conservation concern, such as endangered sturgeons. Our objectives were to design an efficient survey methodology for sampling Atlantic Sturgeon Acipenser oxyrinchus by using side-scan sonar and to developmethods for analyzing these data. In North Carolina and South Carolina, we surveyed six rivers thought to contain varying abundances of sturgeon by using a combination of side-scan sonar, telemetry, and video cameras (i.e., to sample jumping sturgeon). Lower reaches of each river near the saltwater-freshwater interface were surveyed on three occasions (generally successive days), and we used occupancy modeling to analyze these data.We were able to detect sturgeon in five of six rivers by using these methods. Side-scan sonar was effective in detecting sturgeon, with estimated gear-specific detection probabilities ranging from 0.2 to 0.5 and river-specific occupancy estimates (per 2-km river segment) ranging from 0.0 to 0.8. Future extensions of this occupancy modeling framework will involve the use of side-scan sonar data to assess sturgeon habitat and abundance in different river systems.

  20. Symmetry-adapted configurational modelling of fractional site occupancy in solids

    Energy Technology Data Exchange (ETDEWEB)

    Grau-Crespo, R [Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ (United Kingdom); Hamad, S [Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ (United Kingdom); Catlow, C R A [Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ (United Kingdom); Leeuw, N H de [Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ (United Kingdom)

    2007-06-27

    A methodology is presented, which reduces the number of site-occupancy configurations to be calculated when modelling site disorder in solids, by taking advantage of the crystal symmetry of the lattice. Within this approach, two configurations are considered equivalent when they are related by an isometric operation; a trial list of possible isometric transformations is provided by the group of symmetry operators in the parent structure, which is used to generate all configurations via atomic substitutions. We have adapted the equations for configurational statistics to operate in the reduced configurational space of the independent configurations. Each configuration in this space is characterized by its reduced energy, which includes not only its energy but also a contribution from its degeneracy in the complete configurational space, via an entropic term. The new computer program SOD (site-occupancy disorder) is presented, which performs this analysis in systems with arbitrary symmetry and any size of supercell. As a case study we use the distribution of cations in iron antimony oxide FeSbO{sub 4}, where we also introduce some general considerations for the modelling of site-occupancy disorder in paramagnetic systems.

  1. A study of critical reasoning in online learning: application of the Occupational Performance Process Model.

    Science.gov (United States)

    Mitchell, Anita Witt; Batorski, Rosemary E

    2009-01-01

    This study examined the effect of an online guided independent study on critical reasoning skills. Twenty-one first-semester Master of Occupational Therapy students completed an online assignment designed to facilitate application of the Occupational Performance Process Model (Fearing & Clark) and kept reflective journals. Data from the journals were analyzed in relation to the three sets of questions, question type and results of the Watson-Glaser Critical Thinking Appraisal (WGCTA). This assignment appeared to be effective for enhancing awareness and use of critical reasoning skills. Differences in patterns of critical reasoning between students with high and low WGCTA scores and results of an inductive analysis of the journal entries are discussed. Future research investigating the types of feedback that effectively facilitate development of critical reasoning and whether students with high and low WGCTA scores might benefit from different types of instruction and/or feedback is recommended. Copyright (c) 2009 John Wiley & Sons, Ltd.

  2. Chemical and natural stressors combined:

    DEFF Research Database (Denmark)

    Gergs, André; Zenker, Armin; Grimm, Volker

    2013-01-01

    In addition to natural stressors, populations are increasingly exposed to chemical pollutants released into the environment. We experimentally demonstrate the loss of resilience for Daphnia magna populations that are exposed to a combination of natural and chemical stressors even though effects...... demonstrates that population size can be a poor endpoint for risk assessments of chemicals and that ignoring disturbance interactions can lead to severe underestimation of extinction risk...

  3. Longitudinal associations between stressors and work ability in hospital workers.

    Science.gov (United States)

    Carmen Martinez, Maria; da Silva Alexandre, Tiago; Dias de Oliveira Latorre, Maria do Rosario; Marina Fischer, Frida

    This study sought to assess associations between work stressors and work ability in a cohort (2009-2012) of 498 hospital workers. Time-dependent variables associated with the Work Ability Index (WAI) were evaluated using general linear mixed models. Analyses included effects of individual and work characteristics. Except for work demands, the work stressors (job control, social support, effort-reward imbalance, overcommitment and work-related activities that cause pain/injury) were associated with WAI (p work and morning shift work were associated with decreased WAI (p Work stressors negatively affected work ability over time independently of other variables.

  4. Additive effects prevail: The response of biota to multiple stressors in an intensively monitored watershed.

    Science.gov (United States)

    Gieswein, Alexander; Hering, Daniel; Feld, Christian K

    2017-09-01

    Freshwater ecosystems are impacted by a range of stressors arising from diverse human-caused land and water uses. Identifying the relative importance of single stressors and understanding how multiple stressors interact and jointly affect biology is crucial for River Basin Management. This study addressed multiple human-induced stressors and their effects on the aquatic flora and fauna based on data from standard WFD monitoring schemes. For altogether 1095 sites within a mountainous catchment, we used 12 stressor variables covering three different stressor groups: riparian land use, physical habitat quality and nutrient enrichment. Twenty-one biological metrics calculated from taxa lists of three organism groups (fish, benthic invertebrates and aquatic macrophytes) served as response variables. Stressor and response variables were subjected to Boosted Regression Tree (BRT) analysis to identify stressor hierarchy and stressor interactions and subsequently to Generalised Linear Regression Modelling (GLM) to quantify the stressors standardised effect size. Our results show that riverine habitat degradation was the dominant stressor group for the river fauna, notably the bed physical habitat structure. Overall, the explained variation in benthic invertebrate metrics was higher than it was in fish and macrophyte metrics. In particular, general integrative (aggregate) metrics such as % Ephemeroptera, Plecoptera and Trichoptera (EPT) taxa performed better than ecological traits (e.g. % feeding types). Overall, additive stressor effects dominated, while significant and meaningful stressor interactions were generally rare and weak. We concluded that given the type of stressor and ecological response variables addressed in this study, river basin managers do not need to bother much about complex stressor interactions, but can focus on the prevailing stressors according to the hierarchy identified. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Model for Estimating Noise-Induced Hearing Loss Associated With Occupational Noise Exposure in a Specified US Navy Population

    National Research Council Canada - National Science Library

    Tufts, Jennifer; Weathersby, Paul K; Marshall, Lynne; Sachs, Felix

    2007-01-01

    This report details the initial steps in the development of a method for modeling the noise-induced hearing loss accrued by a population of Sailors exposed to high-level steady-state occupational noise...

  6. Distal Stressors and Depression among Homeless Men

    OpenAIRE

    Coohey, Carol; Easton, Scott D.

    2016-01-01

    Depression is a common problem among homeless men that may interfere with functional tasks, such as securing stable housing, obtaining employment, and accessing health services. Previous research on depression among homeless men has largely focused on current psychosocial resources, substance abuse, and past victimization. Guided by Ensel and Lin’s life course stress process model, the authors examined whether distal stressors, including victimization and exposure to parent problems in childh...

  7. Integrating occupancy modeling and interview data for corridor identification: A case study for jaguars in Nicaragua

    Science.gov (United States)

    Zeller, K.A.; Nijhawan, S.; Salom-Perez, R.; Potosme, S.H.; Hines, J.E.

    2011-01-01

    Corridors are critical elements in the long-term conservation of wide-ranging species like the jaguar (Panthera onca). Jaguar corridors across the range of the species were initially identified using a GIS-based least-cost corridor model. However, due to inherent errors in remotely sensed data and model uncertainties, these corridors warrant field verification before conservation efforts can begin. We developed a novel corridor assessment protocol based on interview data and site occupancy modeling. We divided our pilot study area, in southeastern Nicaragua, into 71, 6. ??. 6 km sampling units and conducted 160 structured interviews with local residents. Interviews were designed to collect data on jaguar and seven prey species so that detection/non-detection matrices could be constructed for each sampling unit. Jaguars were reportedly detected in 57% of the sampling units and had a detection probability of 28%. With the exception of white-lipped peccary, prey species were reportedly detected in 82-100% of the sampling units. Though the use of interview data may violate some assumptions of the occupancy modeling approach for determining 'proportion of area occupied', we countered these shortcomings through study design and interpreting the occupancy parameter, psi, as 'probability of habitat used'. Probability of habitat use was modeled for each target species using single state or multistate models. A combination of the estimated probabilities of habitat use for jaguar and prey was selected to identify the final jaguar corridor. This protocol provides an efficient field methodology for identifying corridors for easily-identifiable species, across large study areas comprised of unprotected, private lands. ?? 2010 Elsevier Ltd.

  8. An integrated data model to estimate spatiotemporal occupancy, abundance, and colonization dynamics

    Science.gov (United States)

    Williams, Perry J.; Hooten, Mevin B.; Womble, Jamie N.; Esslinger, George G.; Bower, Michael R.; Hefley, Trevor J.

    2017-01-01

    Ecological invasions and colonizations occur dynamically through space and time. Estimating the distribution and abundance of colonizing species is critical for efficient management or conservation. We describe a statistical framework for simultaneously estimating spatiotemporal occupancy and abundance dynamics of a colonizing species. Our method accounts for several issues that are common when modeling spatiotemporal ecological data including multiple levels of detection probability, multiple data sources, and computational limitations that occur when making fine-scale inference over a large spatiotemporal domain. We apply the model to estimate the colonization dynamics of sea otters (Enhydra lutris) in Glacier Bay, in southeastern Alaska.

  9. A Model for Occupational Safety and Health Intervention Diffusion to Small Businesses

    Science.gov (United States)

    Sinclair, Raymond C.; Cunningham, Thomas R.; Schulte, Paul A.

    2015-01-01

    Background Smaller businesses differ from their larger counterparts in having higher rates of occupational injuries and illnesses and fewer resources for preventing those losses. Intervention models developed outside the United States have addressed the resource deficiency issue by incorporating intermediary organizations such as trade associations. Methods This paper extends previous models by using exchange theory and by borrowing from the diffusion of innovations model. It emphasizes that occupational safety and health (OSH) organizations must understand as much about intermediary organizations as they do about small businesses. OSH organizations (“initiators”) must understand how to position interventions and information to intermediaries as added value to their relationships with small businesses. Examples from experiences in two midwestern states are used to illustrate relationships and types of analyses implied by the extended model. Results The study found that intermediary organizations were highly attuned to providing smaller businesses with what they want, including OSH services. The study also found that there are opinion leader organizations and individual champions within intermediaries who are key to decisions and actions about OSH programming. Conclusions The model places more responsibility on both initiators and intermediaries to develop and market interventions that will be valued in the competitive small business environment where the resources required to adopt each new business activity could always be used in other ways. The model is a candidate for empirical validation, and it offers some encouragement that the issue of sustainable OSH assistance to small businesses might be addressed. PMID:24115112

  10. Role models and occupational ambitions of in-school male adolescents

    Directory of Open Access Journals (Sweden)

    Suhail Ahmad Azmi

    2014-01-01

    Full Text Available Background: A role model is perceived as worthy of imitation, their selection can indicate significant elements of psychosocial health and self-projection in adolescents. Patterns of behavior and lifestyle choices established during adolescence can have immediate and lasting effects on health. Materials and Methods: Cross-sectional study was undertaken in the schools of Aligarh, Uttar Pradesh, India. The sample frame was 2347, out of which a sample of 390 students was studied. Data collected were entered and analyzed by SPSS for Windows version 10%. Results: Majority (62.7% of adolescents revealed that their role models were Film Star (34.8% and their Teachers (27.9%, Parents (14.3%, Sportsman (12.0%. Politicians as the role models were opted by least proportion (1.2%. Desire of future occupation was Businessmen (27.9%, Doctor (18.6, and Engineer (14.4%. Conclusion: Nearly all adolescents had a role model. There is greater impact of cinema on the minds of adolescents, which resulted in choosing film actors as their role model. Aspiration of future occupation was not related to the characteristics of the role model.

  11. The Challenge of Cultural Competency in the Multicultural 21st Century: A Conceptual Model to Guide Occupational Therapy Practice

    Directory of Open Access Journals (Sweden)

    Wesam Darawsheh

    2015-04-01

    Full Text Available bstract Background: Occupational therapists increasingly encounter clients from diverse cultural backgrounds and need to meet their professional obligation of delivering culturally competent practice. Yet the process of cultural competency is poorly understood in occupational therapy practice. There is a need for a clear understanding of the meaning and process of cultural competency as it is enacted in practice with a wide range of individuals from culturally diverse backgrounds. Aim: To investigate the process, stages, characteristics, and requirements of cultural competency as practiced by experienced occupational therapists. Method: Semi-structured interviews were carried out with 13 community occupational therapists experienced in delivering occupational therapy services in clients’ homes in a culturally diverse area in London, England. Findings: Interview data were analyzed and ordered into the format of a conceptual process model where cultural competency formed the core concept. The model of cultural competency that emerged from this study comprised six stages: cultural awareness, cultural preparedness, a cultural picture of the person, cultural responsiveness, cultural readiness, and cultural competence. Conclusion: Cultural competency is a complex process that needs to be based on underpinning occupational theory and actualized at the level of practice. Further research is needed to test out the model and illuminate the process of cultural competency in different areas of occupational therapy practice.

  12. A participatory model for improving occupational health and safety: improving informal sector working conditions in Thailand.

    Science.gov (United States)

    Manothum, Aniruth; Rukijkanpanich, Jittra; Thawesaengskulthai, Damrong; Thampitakkul, Boonwa; Chaikittiporn, Chalermchai; Arphorn, Sara

    2009-01-01

    The purpose of this study was to evaluate the implementation of an Occupational Health and Safety Management Model for informal sector workers in Thailand. The studied model was characterized by participatory approaches to preliminary assessment, observation of informal business practices, group discussion and participation, and the use of environmental measurements and samples. This model consisted of four processes: capacity building, risk analysis, problem solving, and monitoring and control. The participants consisted of four local labor groups from different regions, including wood carving, hand-weaving, artificial flower making, and batik processing workers. The results demonstrated that, as a result of applying the model, the working conditions of the informal sector workers had improved to meet necessary standards. This model encouraged the use of local networks, which led to cooperation within the groups to create appropriate technologies to solve their problems. The authors suggest that this model could effectively be applied elsewhere to improve informal sector working conditions on a broader scale.

  13. Dynamic occupancy modelling reveals a hierarchy of competition among fishers, grey foxes and ringtails.

    Science.gov (United States)

    Green, David S; Matthews, Sean M; Swiers, Robert C; Callas, Richard L; Scott Yaeger, J; Farber, Stuart L; Schwartz, Michael K; Powell, Roger A

    2018-05-01

    Determining how species coexist is critical for understanding functional diversity, niche partitioning and interspecific interactions. Identifying the direct and indirect interactions among sympatric carnivores that enable their coexistence is particularly important to elucidate because they are integral for maintaining ecosystem function. We studied the effects of removing nine fishers (Pekania pennanti) on their population dynamics and used this perturbation to elucidate the interspecific interactions among fishers, grey foxes (Urocyon cinereoargenteus) and ringtails (Bassariscus astutus). Grey foxes (family: Canidae) are likely to compete with fishers due to their similar body sizes and dietary overlap, and ringtails (family: Procyonidae), like fishers, are semi-arboreal species of conservation concern. We used spatial capture-recapture to investigate fisher population numbers and dynamic occupancy models that incorporated interspecific interactions to investigate the effects members of these species had on the colonization and persistence of each other's site occupancy. The fisher population showed no change in density for up to 3 years following the removals of fishers for translocations. In contrast, fisher site occupancy decreased in the years immediately following the translocations. During this same time period, site occupancy by grey foxes increased and remained elevated through the end of the study. We found a complicated hierarchy among fishers, foxes and ringtails. Fishers affected grey fox site persistence negatively but had a positive effect on their colonization. Foxes had a positive effect on ringtail site colonization. Thus, fishers were the dominant small carnivore where present and negatively affected foxes directly and ringtails indirectly. Coexistence among the small carnivores we studied appears to reflect dynamic spatial partitioning. Conservation and management efforts should investigate how intraguild interactions may influence the

  14. Social support, stressors, and frailty among older Mexican American adults.

    Science.gov (United States)

    Peek, M Kristen; Howrey, Bret T; Ternent, Rafael Samper; Ray, Laura A; Ottenbacher, Kenneth J

    2012-11-01

    There is little research on the effects of stressors and social support on frailty. Older Mexican Americans, in particular, are at higher risk of medical conditions, such as diabetes, that could contribute to frailty. Given that the Mexican American population is rapidly growing in the United States, it is important to determine whether there are modifiable social factors related to frailty in this older group. To address the influence of social support and stressors on frailty among older Mexican Americans, we utilized five waves of the Hispanic Established Populations for the Epidemiologic Study of the Elderly (Hispanic EPESE) to examine the impact of stressors and social support on frailty over a 12-year period. Using a modified version of the Fried and Walston Frailty Index, we estimated the effects of social support and stressors on frailty over time using trajectory modeling (SAS 9.2, PROC TRAJ). We first grouped respondents according to one of three trajectories: low, progressive moderate, and progressive high frailty. Second, we found that the effects of stressors and social support on frailty varied by trajectory and by type of stressor. Health-related stressors and financial strain were related to increases in frailty over time, whereas social support was related to less-steep increases in frailty. Frailty has been hypothesized to reflect age-related physiological vulnerability to stressors, and the analyses presented indicate partial support for this hypothesis in an older sample of Mexican Americans. Future research needs to incorporate measures of stressors and social support in examining those who become frail, especially in minority populations.

  15. Generalizable occupant-driven optimization model for domestic hot water production in NZEB

    International Nuclear Information System (INIS)

    Kazmi, H.; D’Oca, S.; Delmastro, C.; Lodeweyckx, S.; Corgnati, S.P.

    2016-01-01

    Highlights: • Smart meter data for domestic hot water consumption is collected for 46 NZEB. • Reinforcement learning optimizes energy consumed while constrained on user comfort. • Online optimization models learn occupant behaviour and system thermodynamics. • Offline generalizable models calibrate dynamically the storage vessel operation. • Real world application of the active controls resulted in energy savings of 27%. - Abstract: The primary objective of this paper is to demonstrate improved energy efficiency for domestic hot water (DHW) production in residential buildings. This is done by deriving data-driven optimal heating schedules (used interchangeably with policies) automatically. The optimization leverages actively learnt occupant behaviour and models for thermodynamics of the storage vessel to operate the heating mechanism – an air-source heat pump (ASHP) in this case – at the highest possible efficiency. The proposed algorithm, while tested on an ASHP, is essentially decoupled from the heating mechanism making it sufficiently robust to generalize to other types of heating mechanisms as well. Simulation results for this optimization based on data from 46 Net-Zero Energy Buildings (NZEB) in the Netherlands are presented. These show a reduction of energy consumption for DHW by 20% using a computationally inexpensive heuristic approach, and 27% when using a more intensive hybrid ant colony optimization based method. The energy savings are strongly dependent on occupant comfort level. This is demonstrated in real-world settings for a low-consumption house where active control was performed using heuristics for 3.5 months and resulted in energy savings of 27% (61 kW h). It is straightforward to extend the same models to perform automatic demand side management (ADSM) by treating the DHW vessel as a flexibility bearing device.

  16. Stressor controllability modulates fear extinction in humans

    Science.gov (United States)

    Hartley, Catherine A.; Gorun, Alyson; Reddan, Marianne C.; Ramirez, Franchesca; Phelps, Elizabeth A.

    2014-01-01

    Traumatic events are proposed to play a role in the development of anxiety disorders, however not all individuals exposed to extreme stress experience a pathological increase in fear. Recent studies in animal models suggest that the degree to which one is able to control an aversive experience is a critical factor determining its behavioral consequences. In this study, we examined whether stressor controllability modulates subsequent conditioned fear expression in humans. Participants were randomly assigned to an escapable stressor condition, a yoked inescapable stressor condition, or a control condition involving no stress exposure. One week later, all participants underwent fear conditioning, fear extinction, and a test of extinction retrieval the following day. Participants exposed to inescapable stress showed impaired fear extinction learning and increased fear expression the following day. In contrast, escapable stress improved fear extinction and prevented the spontaneous recovery of fear. Consistent with the bidirectional controllability effects previously reported in animal models, these results suggest that one's degree of control over aversive experiences may be an important factor influencing the development of psychological resilience or vulnerability in humans. PMID:24333646

  17. Integrated presentation of ecological risk from multiple stressors

    OpenAIRE

    Goussen, Benoit Regis Marc; Price, Oliver R.; Rendal, Cecilie; Ashauer, Roman

    2016-01-01

    Current environmental risk assessments (ERA) do not account explicitly for ecological factors (e.g. species composition, temperature or food availability) and multiple stressors. Assessing mixtures of chemical and ecological stressors is needed as well as accounting for variability in environmental conditions and uncertainty of data and models. Here we propose a novel probabilistic ERA framework to overcome these limitations, which focusses on visualising assessment outcomes by construct-ing ...

  18. Examining the mediating effect of work-to-family conflict on the associations between job stressors and employee psychological distress: a prospective cohort study.

    Science.gov (United States)

    Oshio, Takashi; Inoue, Akiomi; Tsutsumi, Akizumi

    2017-08-03

    The mediating effect of work-to-family conflict (WFC) on the associations between eight types of job stressors (measured based on the job demands-control, effort-reward imbalance and organisational justice models) and psychological distress in employees was examined. This study employed a prospective design. An occupational cohort study in Japan (Japanese Study of Health, Occupation, and Psychosocial Factors Related Equity; J-HOPE). 5859 men and 1560 women who were working for 11 firms and participated at three consecutive waves of J-HOPE, at 1-year intervals, from 2010 to 2013. Psychological distress, as measured by Kessler 6 scores. Mediation analysis using data on job stressors at baseline, WFC at 1-year follow-up and psychological distress at 2-year follow-up showed that WFC mediated 39.1% (95% CI 29.1% to 49.1%) and 44.5% (95% CI 31.4% to 51.7%) of the associations of psychological distress with job demands and effort, respectively, for men. The mediating effect of WFC was smaller for job stressors indicating reduced job resources, compared with job demands and effort. The mediating effect of WFC was somewhat larger for women than it was for men, with WFC mediating 47.5% (95% CI 22.5% to 72.6%) and 64.0% (95% CI 24.3% to 100.0%) of the associations of psychological distress with job demands and effort, respectively. WFC was a key mediator in the associations between most job stressors and employee psychological distress. Results suggest that policy measures and support from supervisors, to prevent job stressors from adding to WFC, are needed to reduce employee psychological distress. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  19. Examining the mediating effect of work-to-family conflict on the associations between job stressors and employee psychological distress: a prospective cohort study

    Science.gov (United States)

    Oshio, Takashi; Inoue, Akiomi; Tsutsumi, Akizumi

    2017-01-01

    Objectives The mediating effect of work-to-family conflict (WFC) on the associations between eight types of job stressors (measured based on the job demands-control, effort–reward imbalance and organisational justice models) and psychological distress in employees was examined. Design This study employed a prospective design. Setting An occupational cohort study in Japan (Japanese Study of Health, Occupation, and Psychosocial Factors Related Equity; J-HOPE). Participants 5859 men and 1560 women who were working for 11 firms and participated at three consecutive waves of J-HOPE, at 1-year intervals, from 2010 to 2013. Main outcome measures Psychological distress, as measured by Kessler 6 scores. Results Mediation analysis using data on job stressors at baseline, WFC at 1-year follow-up and psychological distress at 2-year follow-up showed that WFC mediated 39.1% (95% CI 29.1% to 49.1%) and 44.5% (95% CI 31.4% to 51.7%) of the associations of psychological distress with job demands and effort, respectively, for men. The mediating effect of WFC was smaller for job stressors indicating reduced job resources, compared with job demands and effort. The mediating effect of WFC was somewhat larger for women than it was for men, with WFC mediating 47.5% (95% CI 22.5% to 72.6%) and 64.0% (95% CI 24.3% to 100.0%) of the associations of psychological distress with job demands and effort, respectively. Conclusions WFC was a key mediator in the associations between most job stressors and employee psychological distress. Results suggest that policy measures and support from supervisors, to prevent job stressors from adding to WFC, are needed to reduce employee psychological distress. PMID:28775183

  20. Recommended survey designs for occupancy modelling using motion-activated cameras: insights from empirical wildlife data

    Directory of Open Access Journals (Sweden)

    Graeme Shannon

    2014-08-01

    Full Text Available Motion-activated cameras are a versatile tool that wildlife biologists can use for sampling wild animal populations to estimate species occurrence. Occupancy modelling provides a flexible framework for the analysis of these data; explicitly recognizing that given a species occupies an area the probability of detecting it is often less than one. Despite the number of studies using camera data in an occupancy framework, there is only limited guidance from the scientific literature about survey design trade-offs when using motion-activated cameras. A fuller understanding of these trade-offs will allow researchers to maximise available resources and determine whether the objectives of a monitoring program or research study are achievable. We use an empirical dataset collected from 40 cameras deployed across 160 km2 of the Western Slope of Colorado, USA to explore how survey effort (number of cameras deployed and the length of sampling period affects the accuracy and precision (i.e., error of the occupancy estimate for ten mammal and three virtual species. We do this using a simulation approach where species occupancy and detection parameters were informed by empirical data from motion-activated cameras. A total of 54 survey designs were considered by varying combinations of sites (10–120 cameras and occasions (20–120 survey days. Our findings demonstrate that increasing total sampling effort generally decreases error associated with the occupancy estimate, but changing the number of sites or sampling duration can have very different results, depending on whether a species is spatially common or rare (occupancy = ψ and easy or hard to detect when available (detection probability = p. For rare species with a low probability of detection (i.e., raccoon and spotted skunk the required survey effort includes maximizing the number of sites and the number of survey days, often to a level that may be logistically unrealistic for many studies. For common

  1. The effect of precrash velocity reduction on occupant response using a human body finite element model.

    Science.gov (United States)

    Guleyupoglu, B; Schap, J; Kusano, K D; Gayzik, F S

    2017-07-04

    The objective of this study is to use a validated finite element model of the human body and a certified model of an anthropomorphic test dummy (ATD) to evaluate the effect of simulated precrash braking on driver kinematics, restraint loads, body loads, and computed injury criteria in 4 commonly injured body regions. The Global Human Body Models Consortium (GHBMC) 50th percentile male occupant (M50-O) and the Humanetics Hybrid III 50th percentile models were gravity settled in the driver position of a generic interior equipped with an advanced 3-point belt and driver airbag. Fifteen simulations per model (30 total) were conducted, including 4 scenarios at 3 severity levels: median, severe, and the U.S. New Car Assessment Program (U.S.-NCAP) and 3 extra per model with high-intensity braking. The 4 scenarios were no precollision system (no PCS), forward collision warning (FCW), FCW with prebraking assist (FCW+PBA), and FCW and PBA with autonomous precrash braking (FCW + PBA + PB). The baseline ΔV was 17, 34, and 56.4 kph for median, severe, and U.S.-NCAP scenarios, respectively, and were based on crash reconstructions from NASS/CDS. Pulses were then developed based on the assumed precrash systems equipped. Restraint properties and the generic pulse used were based on literature. In median crash severity cases, little to no risk (braking cases (1.0-1.4 g), head injury criterion (HIC), brain injury criterion (BrIC), and chest deflection injury measures increased with increased braking intensity. All other measures for these cases tended to decrease. The ATD also predicted and trended similar to the human body models predictions for both the median, severe, and NCAP cases. Forward excursion for both models decreased across median, severe, and NCAP cases and diverged from each other in cases above 1.0 g of braking intensity. The addition of precrash systems simulated through reduced precrash speeds caused reductions in some injury criteria, whereas others (chest

  2. Exploring the squeezed three-point galaxy correlation function with generalized halo occupation distribution models

    Science.gov (United States)

    Yuan, Sihan; Eisenstein, Daniel J.; Garrison, Lehman H.

    2018-04-01

    We present the GeneRalized ANd Differentiable Halo Occupation Distribution (GRAND-HOD) routine that generalizes the standard 5 parameter halo occupation distribution model (HOD) with various halo-scale physics and assembly bias. We describe the methodology of 4 different generalizations: satellite distribution generalization, velocity bias, closest approach distance generalization, and assembly bias. We showcase the signatures of these generalizations in the 2-point correlation function (2PCF) and the squeezed 3-point correlation function (squeezed 3PCF). We identify generalized HOD prescriptions that are nearly degenerate in the projected 2PCF and demonstrate that these degeneracies are broken in the redshift-space anisotropic 2PCF and the squeezed 3PCF. We also discuss the possibility of identifying degeneracies in the anisotropic 2PCF and further demonstrate the extra constraining power of the squeezed 3PCF on galaxy-halo connection models. We find that within our current HOD framework, the anisotropic 2PCF can predict the squeezed 3PCF better than its statistical error. This implies that a discordant squeezed 3PCF measurement could falsify the particular HOD model space. Alternatively, it is possible that further generalizations of the HOD model would open opportunities for the squeezed 3PCF to provide novel parameter measurements. The GRAND-HOD Python package is publicly available at https://github.com/SandyYuan/GRAND-HOD.

  3. Modeled occupational exposures to gas-phase medical laser-generated air contaminants.

    Science.gov (United States)

    Lippert, Julia F; Lacey, Steven E; Jones, Rachael M

    2014-01-01

    Exposure monitoring data indicate the potential for substantive exposure to laser-generated air contaminants (LGAC); however the diversity of medical lasers and their applications limit generalization from direct workplace monitoring. Emission rates of seven previously reported gas-phase constituents of medical laser-generated air contaminants (LGAC) were determined experimentally and used in a semi-empirical two-zone model to estimate a range of plausible occupational exposures to health care staff. Single-source emission rates were generated in an emission chamber as a one-compartment mass balance model at steady-state. Clinical facility parameters such as room size and ventilation rate were based on standard ventilation and environmental conditions required for a laser surgical facility in compliance with regulatory agencies. All input variables in the model including point source emission rates were varied over an appropriate distribution in a Monte Carlo simulation to generate a range of time-weighted average (TWA) concentrations in the near and far field zones of the room in a conservative approach inclusive of all contributing factors to inform future predictive models. The concentrations were assessed for risk and the highest values were shown to be at least three orders of magnitude lower than the relevant occupational exposure limits (OELs). Estimated values do not appear to present a significant exposure hazard within the conditions of our emission rate estimates.

  4. A novel complex air supply model for indoor air quality control via the occupant micro-environment demand ventilation

    International Nuclear Information System (INIS)

    Yang, Jie; Zhou, Bo; Jin, Maozhu; Wang, Jun; Xiong, Feng

    2016-01-01

    Protection of indoor air quality and human health can be achieved via ventilation, which has becomes one of the most important tasks for sustainable buildings. This approach also requires highly efficient and energy saving methods for modern building ventilations consisting of a set of parameters of the complex indoor system. Therefore, the advancement in understanding the characteristics of various ventilation methods is highly necessary. This study presents one novel air supply model for the complex occupant micro-environment demand control ventilations, to analyze the efficiency of various ventilation types. This model is established primarily according to the momentum and mass conservations, and goal of occupant micro-environment demand, which is a complex system with the characteristics of diversity and dynamic variation. As for different occupant densities, characteristics of outdoor air supply for controlling gaseous pollutant and three basic features of outdoor airflow supply reaching occupant micro-environment were obtained. This research shows that for various types of occupant density and storey height, the rising and descending rates of the demand outdoor airflow in mixing ventilation are higher than those under displacement ventilation conditions. In addition, since the structure is better designed and sewage flow is more efficient, the mixing ventilation also requires a much higher peak demand outdoor airflow than its counterpart. The increase of storey height will lead to a decline of pollutants in the breathing zone and the demand outdoor airflow. Fluctuations of air flow diffusion caused by the change of occupant density in architectural space, will lead to variations of outdoor airflow reaching occupant micro-environment. Accordingly, it would lead to the different peak values of demand outdoor airflow, and the difference becomes even significant if the occupant density increases. The variations of the air supply and fraction of air reaching the

  5. Analysis and modeling of active occupancy of the residential sector in Spain: An indicator of residential electricity consumption

    International Nuclear Information System (INIS)

    López-Rodríguez, M.A.; Santiago, I.; Trillo-Montero, D.; Torriti, J.; Moreno-Munoz, A.

    2013-01-01

    The growing energy consumption in the residential sector represents about 30% of global demand. This calls for Demand Side Management solutions propelling change in behaviors of end consumers, with the aim to reduce overall consumption as well as shift it to periods in which demand is lower and where the cost of generating energy is lower. Demand Side Management solutions require detailed knowledge about the patterns of energy consumption. The profile of electricity demand in the residential sector is highly correlated with the time of active occupancy of the dwellings; therefore in this study the occupancy patterns in Spanish properties was determined using the 2009–2010 Time Use Survey (TUS), conducted by the National Statistical Institute of Spain. The survey identifies three peaks in active occupancy, which coincide with morning, noon and evening. This information has been used to input into a stochastic model which generates active occupancy profiles of dwellings, with the aim to simulate domestic electricity consumption. TUS data were also used to identify which appliance-related activities could be considered for Demand Side Management solutions during the three peaks of occupancy. -- Highlights: •Active occupancy profiles of Spanish dwellings has been obtained and modeled from Time Use Survey data. •Occupancy profiles resulting from the model can be used to model domestic energy consumption. •The presence of three peaks of active occupation was verified, which coincide with morning, noon and evening. •Manual and incentive-based DSM programmes are considered the most suitable for Spanish dwellings. •TV electricity consumption becomes important at aggregate level

  6. Distal Stressors and Depression among Homeless Men.

    Science.gov (United States)

    Coohey, Carol; Easton, Scott D

    2016-05-01

    Depression is a common problem among homeless men that may interfere with functional tasks, such as securing stable housing, obtaining employment, and accessing health services. Previous research on depression among homeless men has largely focused on current psychosocial resources, substance abuse, and past victimization. Guided by Ensel and Lin's life course stress process model, the authors examined whether distal stressors, including victimization and exposure to parent problems in childhood, contributed to men's depression above and beyond current (or proximal) stressors, such as substance abuse and health problems, and social resources. The sample consisted of 309 homeless men who had entered a federally funded emergency shelter. Using the Burns Depression Checklist, the authors found that one out of three men met the threshold for moderate to severe depression during the past week. The logistic regression showed that past exposure to parent problems was related to depression after accounting for current stressors and social resources (number of close adult relationships and whether their emotional support needs were met). Past victimization was not related to depression. To address men's depression, workers should concurrently provide services that meet men's basic needs (for example, housing) and address their relationship needs, including their need for emotional support.

  7. Job stress, fatigue, and job dissatisfaction in Dutch lorry drivers: towards an occupation specific model of job demands and control.

    Science.gov (United States)

    de Croon, E M; Blonk, R W B; de Zwart, B C H; Frings-Dresen, M H W; Broersen, J P J

    2002-06-01

    Building on Karasek's model of job demands and control (JD-C model), this study examined the effects of job control, quantitative workload, and two occupation specific job demands (physical demands and supervisor demands) on fatigue and job dissatisfaction in Dutch lorry drivers. From 1181 lorry drivers (adjusted response 63%) self reported information was gathered by questionnaire on the independent variables (job control, quantitative workload, physical demands, and supervisor demands) and the dependent variables (fatigue and job dissatisfaction). Stepwise multiple regression analyses were performed to examine the main effects of job demands and job control and the interaction effect between job control and job demands on fatigue and job dissatisfaction. The inclusion of physical and supervisor demands in the JD-C model explained a significant amount of variance in fatigue (3%) and job dissatisfaction (7%) over and above job control and quantitative workload. Moreover, in accordance with Karasek's interaction hypothesis, job control buffered the positive relation between quantitative workload and job dissatisfaction. Despite methodological limitations, the results suggest that the inclusion of (occupation) specific job control and job demand measures is a fruitful elaboration of the JD-C model. The occupation specific JD-C model gives occupational stress researchers better insight into the relation between the psychosocial work environment and wellbeing. Moreover, the occupation specific JD-C model may give practitioners more concrete and useful information about risk factors in the psychosocial work environment. Therefore, this model may provide points of departure for effective stress reducing interventions at work.

  8. Daily Emotional and Physical Reactivity to Stressors Among Widowed and Married Older Adults

    Science.gov (United States)

    2014-01-01

    Objectives. Widowhood may result in declines in health and potentially stressful changes to daily routines. However, little research has examined how daily stressors contribute to physical and emotional well-being in widowhood. The objectives of the current study were to examine daily stressor exposure and reactivity in widowed versus married older adults. Method. Participants included all 100 widowed and 342 married adults aged 65 and older from the National Study of Daily Experiences, a daily diary study from the second wave of the Midlife in the United States. Daily stressors were measured using the Daily Inventory of Stressful Events; multilevel modeling assessed daily reactivity to stressors using daily negative affect (emotional reactivity) and daily physical symptoms (physical reactivity) as outcomes. Results. Married participants reported more stressors in general, and specifically more interpersonal stressors (e.g., arguments). Both married and widowed participants were reactive to daily stressors. Married participants were physically and emotionally reactive to interpersonal stressors. Widowed participants were more physically reactive to home-related stressors. Discussion. Attention to the types of daily stressors that widowed older adults experience in daily life and the potential physical effects of daily stressors during widowhood may help to alleviate some of the physical distress that widowed older adults may experience. PMID:23685921

  9. Daily emotional and physical reactivity to stressors among widowed and married older adults.

    Science.gov (United States)

    Hahn, Elizabeth A; Cichy, Kelly E; Small, Brent J; Almeida, David M

    2014-01-01

    Widowhood may result in declines in health and potentially stressful changes to daily routines. However, little research has examined how daily stressors contribute to physical and emotional well-being in widowhood. The objectives of the current study were to examine daily stressor exposure and reactivity in widowed versus married older adults. Participants included all 100 widowed and 342 married adults aged 65 and older from the National Study of Daily Experiences, a daily diary study from the second wave of the Midlife in the United States. Daily stressors were measured using the Daily Inventory of Stressful Events; multilevel modeling assessed daily reactivity to stressors using daily negative affect (emotional reactivity) and daily physical symptoms (physical reactivity) as outcomes. Married participants reported more stressors in general, and specifically more interpersonal stressors (e.g., arguments). Both married and widowed participants were reactive to daily stressors. Married participants were physically and emotionally reactive to interpersonal stressors. Widowed participants were more physically reactive to home-related stressors. Attention to the types of daily stressors that widowed older adults experience in daily life and the potential physical effects of daily stressors during widowhood may help to alleviate some of the physical distress that widowed older adults may experience.

  10. Modeling of Individual and Organizational Factors Affecting Traumatic Occupational Injuries Based on the Structural Equation Modeling: A Case Study in Large Construction Industries.

    Science.gov (United States)

    Mohammadfam, Iraj; Soltanzadeh, Ahmad; Moghimbeigi, Abbas; Akbarzadeh, Mehdi

    2016-09-01

    Individual and organizational factors are the factors influencing traumatic occupational injuries. The aim of the present study was the short path analysis of the severity of occupational injuries based on individual and organizational factors. The present cross-sectional analytical study was implemented on traumatic occupational injuries within a ten-year timeframe in 13 large Iranian construction industries. Modeling and data analysis were done using the structural equation modeling (SEM) approach and the IBM SPSS AMOS statistical software version 22.0, respectively. The mean age and working experience of the injured workers were 28.03 ± 5.33 and 4.53 ± 3.82 years, respectively. The portions of construction and installation activities of traumatic occupational injuries were 64.4% and 18.1%, respectively. The SEM findings showed that the individual, organizational and accident type factors significantly were considered as effective factors on occupational injuries' severity (P accidents' severity in large construction industries.

  11. Evaluating the predictive abilities of community occupancy models using AUC while accounting for imperfect detection

    Science.gov (United States)

    Zipkin, Elise F.; Grant, Evan H. Campbell; Fagan, William F.

    2012-01-01

    The ability to accurately predict patterns of species' occurrences is fundamental to the successful management of animal communities. To determine optimal management strategies, it is essential to understand species-habitat relationships and how species habitat use is related to natural or human-induced environmental changes. Using five years of monitoring data in the Chesapeake and Ohio Canal National Historical Park, Maryland, USA, we developed four multi-species hierarchical models for estimating amphibian wetland use that account for imperfect detection during sampling. The models were designed to determine which factors (wetland habitat characteristics, annual trend effects, spring/summer precipitation, and previous wetland occupancy) were most important for predicting future habitat use. We used the models to make predictions of species occurrences in sampled and unsampled wetlands and evaluated model projections using additional data. Using a Bayesian approach, we calculated a posterior distribution of receiver operating characteristic area under the curve (ROC AUC) values, which allowed us to explicitly quantify the uncertainty in the quality of our predictions and to account for false negatives in the evaluation dataset. We found that wetland hydroperiod (the length of time that a wetland holds water) as well as the occurrence state in the prior year were generally the most important factors in determining occupancy. The model with only habitat covariates predicted species occurrences well; however, knowledge of wetland use in the previous year significantly improved predictive ability at the community level and for two of 12 species/species complexes. Our results demonstrate the utility of multi-species models for understanding which factors affect species habitat use of an entire community (of species) and provide an improved methodology using AUC that is helpful for quantifying the uncertainty in model predictions while explicitly accounting for

  12. Using Satellite and Airborne LiDAR to Model Woodpecker Habitat Occupancy at the Landscape Scale

    Science.gov (United States)

    Vierling, Lee A.; Vierling, Kerri T.; Adam, Patrick; Hudak, Andrew T.

    2013-01-01

    Incorporating vertical vegetation structure into models of animal distributions can improve understanding of the patterns and processes governing habitat selection. LiDAR can provide such structural information, but these data are typically collected via aircraft and thus are limited in spatial extent. Our objective was to explore the utility of satellite-based LiDAR data from the Geoscience Laser Altimeter System (GLAS) relative to airborne-based LiDAR to model the north Idaho breeding distribution of a forest-dependent ecosystem engineer, the Red-naped sapsucker (Sphyrapicus nuchalis). GLAS data occurred within ca. 64 m diameter ellipses spaced a minimum of 172 m apart, and all occupancy analyses were confined to this grain scale. Using a hierarchical approach, we modeled Red-naped sapsucker occupancy as a function of LiDAR metrics derived from both platforms. Occupancy models based on satellite data were weak, possibly because the data within the GLAS ellipse did not fully represent habitat characteristics important for this species. The most important structural variables influencing Red-naped Sapsucker breeding site selection based on airborne LiDAR data included foliage height diversity, the distance between major strata in the canopy vertical profile, and the vegetation density near the ground. These characteristics are consistent with the diversity of foraging activities exhibited by this species. To our knowledge, this study represents the first to examine the utility of satellite-based LiDAR to model animal distributions. The large area of each GLAS ellipse and the non-contiguous nature of GLAS data may pose significant challenges for wildlife distribution modeling; nevertheless these data can provide useful information on ecosystem vertical structure, particularly in areas of gentle terrain. Additional work is thus warranted to utilize LiDAR datasets collected from both airborne and past and future satellite platforms (e.g. GLAS, and the planned IceSAT2

  13. Burnout and hopelessness among farmers: The Farmers Stressors Inventory.

    Science.gov (United States)

    Truchot, Didier; Andela, Marie

    2018-05-03

    Farming is a stressful occupation with a high rate of suicide. However, there have been relatively few studies that have examined the antecedents of stress and suicide in farmers. We also lack methodologically sound scales aimed at assessing the stressors faced by farmers. Therefore, the purposes of this study were to develop an instrument assessing the stressors met by farmers, The Farmers Stressors Inventory, and to test its factorial structure, internal consistency and criterion validity. First, based on the existing literature and interviews with farmers, we designed a scale containing 37 items. Then a sample of 2142 French farmers completed a questionnaire containing the 37 items along with two measures: The MBIGS that assesses burnout and the BHS that assesses hopelessness. The statistical analyses (EFA and CFA) revealed eight factors in accordance with different aspects of farmers job stressors: workload and lack of time, incertitude toward the future and the financial market, agricultural legislation pressure, social and geographical isolation, financial worry, conflicts with associates or family members, family succession of the farm, and unpredictable interference with farm work. The internal consistency of the eight subscales was satisfactory. Correlation between these eight dimensions and burnout on the one side and hopelessness on the other side support the criterion-related validity of the scale.

  14. Landscape capability models as a tool to predict fine-scale forest bird occupancy and abundance

    Science.gov (United States)

    Loman, Zachary G.; DeLuca, William; Harrison, Daniel J.; Loftin, Cynthia S.; Rolek, Brian W.; Wood, Petra B.

    2018-01-01

    ContextSpecies-specific models of landscape capability (LC) can inform landscape conservation design. Landscape capability is “the ability of the landscape to provide the environment […] and the local resources […] needed for survival and reproduction […] in sufficient quantity, quality and accessibility to meet the life history requirements of individuals and local populations.” Landscape capability incorporates species’ life histories, ecologies, and distributions to model habitat for current and future landscapes and climates as a proactive strategy for conservation planning.ObjectivesWe tested the ability of a set of LC models to explain variation in point occupancy and abundance for seven bird species representative of spruce-fir, mixed conifer-hardwood, and riparian and wooded wetland macrohabitats.MethodsWe compiled point count data sets used for biological inventory, species monitoring, and field studies across the northeastern United States to create an independent validation data set. Our validation explicitly accounted for underestimation in validation data using joint distance and time removal sampling.ResultsBlackpoll warbler (Setophaga striata), wood thrush (Hylocichla mustelina), and Louisiana (Parkesia motacilla) and northern waterthrush (P. noveboracensis) models were validated as predicting variation in abundance, although this varied from not biologically meaningful (1%) to strongly meaningful (59%). We verified all seven species models [including ovenbird (Seiurus aurocapilla), blackburnian (Setophaga fusca) and cerulean warbler (Setophaga cerulea)], as all were positively related to occupancy data.ConclusionsLC models represent a useful tool for conservation planning owing to their predictive ability over a regional extent. As improved remote-sensed data become available, LC layers are updated, which will improve predictions.

  15. Novel application of explicit dynamics occupancy models to ongoing aquatic invasions

    Science.gov (United States)

    Sepulveda, Adam J.

    2018-01-01

    Identification of suitable habitats, where invasive species can establish, is an important step towards controlling their spread. Accurate identification is difficult for new or slow invaders because unoccupied habitats may be suitable, given enough time for dispersal, while occupied habitats may prove to be unsuitable for establishment.To identify the suitable habitat of a recent invader, I used an explicit dynamics occupancy modelling framework to evaluate habitat covariates related to successful and failed establishments of American bullfrogs (Lithobates catesbeianus) within the Yellowstone River floodplain of Montana, USA from 2012-2016.During this five-year period, bullfrogs failed to establish at most sites they colonized. Bullfrog establishment was most likely to occur and least likely to fail at sites closest to human-modified ponds and lakes and those with emergent vegetation. These habitat covariates were generally associated with the presence of permanent water.Suitable habitat for bullfrog establishment is abundant in the Yellowstone River floodplain, though many sites with suitable habitat remain uncolonized. Thus, the maximum distribution of bullfrogs is much greater than their current distribution.Synthesis and applications. Focused control efforts on habitats with or proximate to permanent waters are most likely to reduce the potential for invasive bullfrog establishment and spread in the Yellowstone River. The novel application of explicit dynamics occupancy models is a useful and widely applicable tool for guiding management efforts towards those habitats where new or slow invaders are most likely to establish and persist.

  16. Occupancy Models for Monitoring Marine Fish: A Bayesian Hierarchical Approach to Model Imperfect Detection with a Novel Gear Combination

    Science.gov (United States)

    Coggins, Lewis G.; Bacheler, Nathan M.; Gwinn, Daniel C.

    2014-01-01

    Occupancy models using incidence data collected repeatedly at sites across the range of a population are increasingly employed to infer patterns and processes influencing population distribution and dynamics. While such work is common in terrestrial systems, fewer examples exist in marine applications. This disparity likely exists because the replicate samples required by these models to account for imperfect detection are often impractical to obtain when surveying aquatic organisms, particularly fishes. We employ simultaneous sampling using fish traps and novel underwater camera observations to generate the requisite replicate samples for occupancy models of red snapper, a reef fish species. Since the replicate samples are collected simultaneously by multiple sampling devices, many typical problems encountered when obtaining replicate observations are avoided. Our results suggest that augmenting traditional fish trap sampling with camera observations not only doubled the probability of detecting red snapper in reef habitats off the Southeast coast of the United States, but supplied the necessary observations to infer factors influencing population distribution and abundance while accounting for imperfect detection. We found that detection probabilities tended to be higher for camera traps than traditional fish traps. Furthermore, camera trap detections were influenced by the current direction and turbidity of the water, indicating that collecting data on these variables is important for future monitoring. These models indicate that the distribution and abundance of this species is more heavily influenced by latitude and depth than by micro-scale reef characteristics lending credence to previous characterizations of red snapper as a reef habitat generalist. This study demonstrates the utility of simultaneous sampling devices, including camera traps, in aquatic environments to inform occupancy models and account for imperfect detection when describing factors

  17. Occupancy models for monitoring marine fish: a bayesian hierarchical approach to model imperfect detection with a novel gear combination.

    Directory of Open Access Journals (Sweden)

    Lewis G Coggins

    Full Text Available Occupancy models using incidence data collected repeatedly at sites across the range of a population are increasingly employed to infer patterns and processes influencing population distribution and dynamics. While such work is common in terrestrial systems, fewer examples exist in marine applications. This disparity likely exists because the replicate samples required by these models to account for imperfect detection are often impractical to obtain when surveying aquatic organisms, particularly fishes. We employ simultaneous sampling using fish traps and novel underwater camera observations to generate the requisite replicate samples for occupancy models of red snapper, a reef fish species. Since the replicate samples are collected simultaneously by multiple sampling devices, many typical problems encountered when obtaining replicate observations are avoided. Our results suggest that augmenting traditional fish trap sampling with camera observations not only doubled the probability of detecting red snapper in reef habitats off the Southeast coast of the United States, but supplied the necessary observations to infer factors influencing population distribution and abundance while accounting for imperfect detection. We found that detection probabilities tended to be higher for camera traps than traditional fish traps. Furthermore, camera trap detections were influenced by the current direction and turbidity of the water, indicating that collecting data on these variables is important for future monitoring. These models indicate that the distribution and abundance of this species is more heavily influenced by latitude and depth than by micro-scale reef characteristics lending credence to previous characterizations of red snapper as a reef habitat generalist. This study demonstrates the utility of simultaneous sampling devices, including camera traps, in aquatic environments to inform occupancy models and account for imperfect detection when

  18. Occupancy models for monitoring marine fish: a bayesian hierarchical approach to model imperfect detection with a novel gear combination.

    Science.gov (United States)

    Coggins, Lewis G; Bacheler, Nathan M; Gwinn, Daniel C

    2014-01-01

    Occupancy models using incidence data collected repeatedly at sites across the range of a population are increasingly employed to infer patterns and processes influencing population distribution and dynamics. While such work is common in terrestrial systems, fewer examples exist in marine applications. This disparity likely exists because the replicate samples required by these models to account for imperfect detection are often impractical to obtain when surveying aquatic organisms, particularly fishes. We employ simultaneous sampling using fish traps and novel underwater camera observations to generate the requisite replicate samples for occupancy models of red snapper, a reef fish species. Since the replicate samples are collected simultaneously by multiple sampling devices, many typical problems encountered when obtaining replicate observations are avoided. Our results suggest that augmenting traditional fish trap sampling with camera observations not only doubled the probability of detecting red snapper in reef habitats off the Southeast coast of the United States, but supplied the necessary observations to infer factors influencing population distribution and abundance while accounting for imperfect detection. We found that detection probabilities tended to be higher for camera traps than traditional fish traps. Furthermore, camera trap detections were influenced by the current direction and turbidity of the water, indicating that collecting data on these variables is important for future monitoring. These models indicate that the distribution and abundance of this species is more heavily influenced by latitude and depth than by micro-scale reef characteristics lending credence to previous characterizations of red snapper as a reef habitat generalist. This study demonstrates the utility of simultaneous sampling devices, including camera traps, in aquatic environments to inform occupancy models and account for imperfect detection when describing factors

  19. Occupational stress and psychopathology in health professionals: an explorative study with the multiple indicators multiple causes (MIMIC) model approach.

    Science.gov (United States)

    Iliceto, Paolo; Pompili, Maurizio; Spencer-Thomas, Sally; Ferracuti, Stefano; Erbuto, Denise; Lester, David; Candilera, Gabriella; Girardi, Paolo

    2013-03-01

    Occupational stress is a multivariate process involving sources of pressure, psycho-physiological distress, locus of control, work dissatisfaction, depression, anxiety, mental health disorders, hopelessness, and suicide ideation. Healthcare professionals are known for higher rates of occupational-related distress (burnout and compassion fatigue) and higher rates of suicide. The purpose of this study was to explain the relationships between occupational stress and some psychopathological dimensions in a sample of health professionals. We investigated 156 nurses and physicians, 62 males and 94 females, who were administered self-report questionnaires to assess occupational stress [occupational stress inventory (OSI)], temperament (temperament evaluation of Memphis, Pisa, Paris, and San Diego autoquestionnaire), and hopelessness (Beck hopelessness scale). The best Multiple Indicators Multiple Causes model with five OSI predictors yielded the following results: χ2(9) = 14.47 (p = 0.11); χ2/df = 1.60; comparative fit index = 0.99; root mean square error of approximation = 0.05. This model provided a good fit to the empirical data, showing a strong direct influence of casual variables such as work dissatisfaction, absence of type A behavior, and especially external locus of control, psychological and physiological distress on latent variable psychopathology. Occupational stress is in a complex relationship with temperament and hopelessness and also common among healthcare professionals.

  20. Dynamic multistate site occupancy models to evaluate hypotheses relevant to conservation of Golden Eagles in Denali National Park, Alaska

    Science.gov (United States)

    Martin, Julien; McIntyre, Carol L.; Hines, James E.; Nichols, James D.; Schmutz, Joel A.; MacCluskie, Margaret C.

    2009-01-01

    The recent development of multistate site occupancy models offers great opportunities to frame and solve decision problems for conservation that can be viewed in terms of site occupancy. These models have several characteristics (e.g., they account for detectability) that make them particularly well suited for addressing management and conservation problems. We applied multistate site occupancy models to evaluate hypotheses related to the conservation and management of Golden Eagles (Aquila chrysaetos) in Denali National Park, Alaska, and provided estimates of transition probabilities among three occupancy states for nesting areas (occupied with successful reproduction, occupied with unsuccessful reproduction, and unoccupied). Our estimation models included the effect of potential recreational activities (hikers) and environmental covariates such as a snowshoe hare (Lepus americanus) index on transition probabilities among the three occupancy states. Based on the most parsimonious model, support for the hypothesis of an effect of potential human disturbance on site occupancy dynamics was equivocal. There was some evidence that potential human disturbance negatively affected local colonization of territories, but there was no evidence of an effect on reproductive performance parameters. In addition, models that assume a positive relationship between the hare index and successful reproduction were well supported by the data. The statistical approach that we used is particularly useful to parameterize management models that can then be used to make optimal decisions related to the management of Golden Eagles in Denali. Although in our case we were particularly interested in managing recreational activities, we believe that such models should be useful to for a broad class of management and conservation problems.

  1. Graph configuration model based evaluation of the education-occupation match.

    Science.gov (United States)

    Gadar, Laszlo; Abonyi, Janos

    2018-01-01

    To study education-occupation matchings we developed a bipartite network model of education to work transition and a graph configuration model based metric. We studied the career paths of 15 thousand Hungarian students based on the integrated database of the National Tax Administration, the National Health Insurance Fund, and the higher education information system of the Hungarian Government. A brief analysis of gender pay gap and the spatial distribution of over-education is presented to demonstrate the background of the research and the resulted open dataset. We highlighted the hierarchical and clustered structure of the career paths based on the multi-resolution analysis of the graph modularity. The results of the cluster analysis can support policymakers to fine-tune the fragmented program structure of higher education.

  2. Resources, stressors and psychological distress among older adults in Chennai, India.

    Science.gov (United States)

    Chokkanathan, Srinivasan

    2009-01-01

    Scant information exists on the complex interaction between resources and stressors and their subsequent influence on the psychological distress of older adults in India. Within the framework of resource theory, the present study examined the various pathways through which resources and stressors influence psychological distress by testing four models - the independence model, the stress-suppression model, the counteractive model and the resource-deterioration model. The independence model posits that resources and stressors have a direct relationship with psychological distress. The stress-suppression model hypothesizes that stressors mediate the influence of resources on psychological distress. The counteractive model postulates that stressors mobilize resources, which in turn influence psychological distress. The resource-deterioration model states that stressors deplete resources and subsequently exacerbate distress. In the present study, resources include social support, religiosity and mastery; stressors include life events, abuse and health problems. Psychological distress was measured using the Center for Epidemiological Studies Depression scale and Geriatric Depression Scale. Interviews were conducted among 400 adults aged 65 years and above, randomly selected from the electoral list of urban Chennai, India. The battery of instruments was translated into Tamil (local language) by back-translation. Structural Equation Modeling was conducted to test the three models. The results supported the stress-suppressor model. Resources had an indirect, negative relationship with psychological distress, and stressors had a direct, positive effect on distress. As such there is a need to identify and strengthen the resources available to older adults in India.

  3. Estimation of occupational and nonoccupational nitrogen dioxide exposure for Korean taxi drivers using a microenvironmental model

    International Nuclear Information System (INIS)

    Son, Busoon; Yang, Wonho; Breysse, Patrick; Chung, Taewoong; Lee, Youngshin

    2004-01-01

    Occupational and nonoccupational personal nitrogen dioxide (NO 2 ) exposures were measured using passive samplers for 31 taxi drivers in Asan and Chunan, Korea. Exposures were also estimated using a microenvironmental time-weighted average model based on indoor, outdoor and inside the taxi area measurements. Mean NO 2 indoor and outdoor concentrations inside and outside the taxi drivers' houses were 24.7±10.7 and 23.3±8.3 ppb, respectively, with a mean indoor to outdoor NO 2 ratio of 1.1. Mean personal NO 2 exposure of taxi drivers was 30.3±9.7 ppb. Personal NO 2 exposures for drivers were more strongly correlated with interior vehicle NO 2 levels (r=0.89) rather than indoor residential NO 2 levels (r=0.74) or outdoor NO 2 levels (r=0.71). The main source of NO 2 exposure for taxi drivers was considered to be occupational driving. Interestingly, the NO 2 exposures for drivers' using LPG-fueled vehicles (26.3±1.3 ppb) were significantly lower than those (38.1±1.3 ppb) using diesel-fueled vehicle (P 2 exposure with indoor and outdoor NO 2 levels of the residence, and interior vehicle NO 2 levels (P 2 levels because they drive diesel-using vehicles outdoors in Korea

  4. Calibration of Airframe and Occupant Models for Two Full-Scale Rotorcraft Crash Tests

    Science.gov (United States)

    Annett, Martin S.; Horta, Lucas G.; Polanco, Michael A.

    2012-01-01

    Two full-scale crash tests of an MD-500 helicopter were conducted in 2009 and 2010 at NASA Langley's Landing and Impact Research Facility in support of NASA s Subsonic Rotary Wing Crashworthiness Project. The first crash test was conducted to evaluate the performance of an externally mounted composite deployable energy absorber under combined impact conditions. In the second crash test, the energy absorber was removed to establish baseline loads that are regarded as severe but survivable. Accelerations and kinematic data collected from the crash tests were compared to a system integrated finite element model of the test article. Results from 19 accelerometers placed throughout the airframe were compared to finite element model responses. The model developed for the purposes of predicting acceleration responses from the first crash test was inadequate when evaluating more severe conditions seen in the second crash test. A newly developed model calibration approach that includes uncertainty estimation, parameter sensitivity, impact shape orthogonality, and numerical optimization was used to calibrate model results for the second full-scale crash test. This combination of heuristic and quantitative methods was used to identify modeling deficiencies, evaluate parameter importance, and propose required model changes. It is shown that the multi-dimensional calibration techniques presented here are particularly effective in identifying model adequacy. Acceleration results for the calibrated model were compared to test results and the original model results. There was a noticeable improvement in the pilot and co-pilot region, a slight improvement in the occupant model response, and an over-stiffening effect in the passenger region. This approach should be adopted early on, in combination with the building-block approaches that are customarily used, for model development and test planning guidance. Complete crash simulations with validated finite element models can be used

  5. Job stress, fatigue, and job dissatisfaction in Dutch lorry drivers: towards an occupation specific model of job demands and control

    NARCIS (Netherlands)

    Croon, E.M. de; Blonk, R.W.B.; Zwart, B.C.H. de; Frings-Dresen, M.H.W.; Broersen, J.P.J.

    2002-01-01

    Building on Karasek's model of job demands and control (JD-C model), this study examined the effects of job control, quantitative workload, and two occupation specific job demands on fatigue and job dissatisfaction in Dutch lorry drivers. From 1181 lorry drivers self reported information was

  6. Job stress, fatigue, and job dissatisfaction in Dutch lorry drivers: towards an occupation specific model of job demands and control

    NARCIS (Netherlands)

    de Croon, E. M.; Blonk, R. W. B.; de Zwart, B. C. H.; Frings-Dresen, M. H. W.; Broersen, J. P. J.

    2002-01-01

    Objectives: Building on Karasek's model of job demands and control (JD-C model), this study examined the effects of job control, quantitative workload, and two occupation specific job demands (physical demands and supervisor demands) on fatigue and job dissatisfaction in Dutch lorry drivers.

  7. Adolescent Decision-Making Processes regarding University Entry: A Model Incorporating Cultural Orientation, Motivation and Occupational Variables

    Science.gov (United States)

    Jung, Jae Yup

    2013-01-01

    This study tested a newly developed model of the cognitive decision-making processes of senior high school students related to university entry. The model incorporated variables derived from motivation theory (i.e. expectancy-value theory and the theory of reasoned action), literature on cultural orientation and occupational considerations. A…

  8. Modeling of site occupancy dynamics for northern spotted owls, with emphasis on the effects of barred owls

    Science.gov (United States)

    Olson, Gail S.; Anthony, Robert G.; Forsman, Eric D.; Ackers, Steven H.; Loschl, Peter J.; Reid, Janice A.; Dugger, Katie M.; Glenn, Elizabeth M.; Ripple, William J.

    2005-01-01

    Northern spotted owls (Strix occidentalis caurina) have been studied intensively since their listing as a threatened species by the U.S. Fish and Wildlife Service in 1990. Studies of spotted owl site occupancy have used various binary response measures, but most of these studies have made the assumption that detectability is perfect, or at least high and not variable. Further, previous studies did not consider temporal variation in site occupancy. We used relatively new methods for open population modeling of site occupancy that incorporated imperfect and variable detectability of spotted owls and allowed modeling of temporal variation in site occupancy, extinction, and colonization probabilities. We also examined the effects of barred owl (S. varia) presence on these parameters. We used spotted owl survey data from 1990 to 2002 for 3 study areas in Oregon, USA, and we used program MARK to develop and analyze site occupancy models. We found per visit detection probabilities averaged variable among study years and study areas. Site occupancy probabilities for owl pairs declined greatly on 1 study area and slightly on the other 2 areas. For all owls, including singles and pairs, site occupancy was mostly stable through time. Barred owl presence had a negative effect on spotted owl detection probabilities, and it had either a positive effect on local-extinction probabilities or a negative effect on colonization probabilities. We conclude that further analyses of spotted owls must account for imperfect and variable detectability and barred owl presence to properly interpret results. Further, because barred owl presence is increasing within the range of northern spotted owls, we expect to see further declines in the proportion of sites occupied by spotted owls.

  9. Mechanistic understanding of human-wildlife conflict through a novel application of dynamic occupancy models.

    Science.gov (United States)

    Goswami, Varun R; Medhi, Kamal; Nichols, James D; Oli, Madan K

    2015-08-01

    Crop and livestock depredation by wildlife is a primary driver of human-wildlife conflict, a problem that threatens the coexistence of people and wildlife globally. Understanding mechanisms that underlie depredation patterns holds the key to mitigating conflicts across time and space. However, most studies do not consider imperfect detection and reporting of conflicts, which may lead to incorrect inference regarding its spatiotemporal drivers. We applied dynamic occupancy models to elephant crop depredation data from India between 2005 and 2011 to estimate crop depredation occurrence and model its underlying dynamics as a function of spatiotemporal covariates while accounting for imperfect detection of conflicts. The probability of detecting conflicts was consistently year). The probability of crop depredation occurrence ranged from 0.29 (SE 0.09) to 0.96 (SE 0.04). The probability that sites raided by elephants in primary period t would not be raided in primary period t + 1 varied with elevation gradient in different seasons and was influenced negatively by mean rainfall and village density and positively by distance to forests. Negative effects of rainfall variation and distance to forests best explained variation in the probability that sites not raided by elephants in primary period t would be raided in primary period t + 1. With our novel application of occupancy models, we teased apart the spatiotemporal drivers of conflicts from factors that influence how they are observed, thereby allowing more reliable inference on mechanisms underlying observed conflict patterns. We found that factors associated with increased crop accessibility and availability (e.g., distance to forests and rainfall patterns) were key drivers of elephant crop depredation dynamics. Such an understanding is essential for rigorous prediction of future conflicts, a critical requirement for effective conflict management in the context of increasing human-wildlife interactions. © 2015

  10. Integrating occupational therapy in treating combat stress reaction within a military unit: An intervention model.

    Science.gov (United States)

    Gindi, Shahar; Galili, Giora; Volovic-Shushan, Shani; Adir-Pavis, Shirly

    2016-01-01

    Combat stress reaction (CR) is a syndrome with a wide range of symptoms including changes in soldiers' behaviors, emotional and physiological responses, avoidance and a decrease in both personal and military functioning. The short-term goal in treating CR is a speedy return to healthy functioning, whereas the long-term goal is to prevent the development of PTSD. Previous research has indicated that the achievement of this short-term goal affects the achievement of the long-term goal and vice versa. Effective treatment requires intervention by trained professionals proficient in reinforcing personal and functional identity without psychiatric labelling. The present paper presents a therapeutic model integrating OT in treating CR within a military setting. The model emphasizes the importance of preventing fixation to the role of 'patient' and a rapid return to maximal functioning. Based on Kielhofner's Model of Human Occupation, which aims to promote adaptive and efficient functioning by engaging soldiers in tasks supporting their military identity, empowering functionality, and increasing their perceived competency. The model emphasizes the therapeutic milieu within a military environment. Practical application of this model focuses on interdisciplinary aspects and client-focused application. The paper describes an assessment process for each soldier entering the CR unit and a treatment model integrating OT.

  11. Life-Long Implications of Developmental Exposure to Environmental Stressors: New Perspectives.

    Science.gov (United States)

    Grandjean, Philippe; Barouki, Robert; Bellinger, David C; Casteleyn, Ludwine; Chadwick, Lisa H; Cordier, Sylvaine; Etzel, Ruth A; Gray, Kimberly A; Ha, Eun-Hee; Junien, Claudine; Karagas, Margaret; Kawamoto, Toshihiro; Paige Lawrence, B; Perera, Frederica P; Prins, Gail S; Puga, Alvaro; Rosenfeld, Cheryl S; Sherr, David H; Sly, Peter D; Suk, William; Sun, Qi; Toppari, Jorma; van den Hazel, Peter; Walker, Cheryl L; Heindel, Jerrold J

    2015-10-01

    The Developmental Origins of Health and Disease (DOHaD) paradigm is one of the most rapidly expanding areas of biomedical research. Environmental stressors that can impact on DOHaD encompass a variety of environmental and occupational hazards as well as deficiency and oversupply of nutrients and energy. They can disrupt early developmental processes and lead to increased susceptibility to disease/dysfunctions later in life. Presentations at the fourth Conference on Prenatal Programming and Toxicity in Boston, in October 2014, provided important insights and led to new recommendations for research and public health action. The conference highlighted vulnerable exposure windows that can occur as early as the preconception period and epigenetics as a major mechanism than can lead to disadvantageous "reprogramming" of the genome, thereby potentially resulting in transgenerational effects. Stem cells can also be targets of environmental stressors, thus paving another way for effects that may last a lifetime. Current testing paradigms do not allow proper characterization of risk factors and their interactions. Thus, relevant exposure levels and combinations for testing must be identified from human exposure situations and outcome assessments. Testing of potential underpinning mechanisms and biomarker development require laboratory animal models and in vitro approaches. Only few large-scale birth cohorts exist, and collaboration between birth cohorts on a global scale should be facilitated. DOHaD-based research has a crucial role in establishing factors leading to detrimental outcomes and developing early preventative/remediation strategies to combat these risks.

  12. Analysis of third-party certification approaches using an occupational health and safety conformity-assessment model.

    Science.gov (United States)

    Redinger, C F; Levine, S P

    1998-11-01

    The occupational health and safety conformity-assessment model presented in this article was developed (1) to analyze 22 public and private programs to determine the extent to which these programs use third parties in conformity-assessment determinations, and (2) to establish a framework to guide future policy developments related to the use of third parties in occupational health and safety conformity-assessment activities. The units of analysis for this study included select Occupational Safety and Health Administration programs and standards, International Organization for Standardization-based standards and guidelines, and standards and guidelines developed by nongovernmental bodies. The model is based on a 15-cell matrix that categorizes first-, second-, and third-party activities in terms of assessment, accreditation, and accreditation-recognition activities. The third-party component of the model has three categories: industrial hygiene/safety testing and sampling; product, equipment, and laboratory certification; and, occupational health and safety management system registration/certification. Using the model, 16 of the 22 programs were found to have a third-party component in their conformity-assessment structure. The analysis revealed that (1) the model provides a useful means to describe and analyze various third-party approaches, (2) the model needs modification to capture aspects of traditional governmental conformity-assessment/enforcement activities, and (3) several existing third-party conformity-assessment systems offer robust models that can guide future third-party policy formulation and implementation activities.

  13. Exploring the Stressors of New Librarians

    Science.gov (United States)

    Larrivee, Anne

    2014-01-01

    This article describes the different stressors and anxieties facing new librarians. It also addresses the various ways that new librarians can cope with location, emotional, and work-related stressors. The article is broken into four different categories of stress; some stressors have been more explored than others. The research is based on an…

  14. Military Occupational Stressors in Garrison, Training, and Deployed Environments

    National Research Council Canada - National Science Library

    Adler, Amy

    2004-01-01

    .... According to Lazarus and Folkman (1984), an event or situation is considered stressful when perceived by the individual as taxing or exceeding coping resources, competencies, values, or self-concept...

  15. Integrated presentation of ecological risk from multiple stressors

    Science.gov (United States)

    Goussen, Benoit; Price, Oliver R.; Rendal, Cecilie; Ashauer, Roman

    2016-10-01

    Current environmental risk assessments (ERA) do not account explicitly for ecological factors (e.g. species composition, temperature or food availability) and multiple stressors. Assessing mixtures of chemical and ecological stressors is needed as well as accounting for variability in environmental conditions and uncertainty of data and models. Here we propose a novel probabilistic ERA framework to overcome these limitations, which focusses on visualising assessment outcomes by construct-ing and interpreting prevalence plots as a quantitative prediction of risk. Key components include environmental scenarios that integrate exposure and ecology, and ecological modelling of relevant endpoints to assess the effect of a combination of stressors. Our illustrative results demonstrate the importance of regional differences in environmental conditions and the confounding interactions of stressors. Using this framework and prevalence plots provides a risk-based approach that combines risk assessment and risk management in a meaningful way and presents a truly mechanistic alternative to the threshold approach. Even whilst research continues to improve the underlying models and data, regulators and decision makers can already use the framework and prevalence plots. The integration of multiple stressors, environmental conditions and variability makes ERA more relevant and realistic.

  16. Integrated presentation of ecological risk from multiple stressors.

    Science.gov (United States)

    Goussen, Benoit; Price, Oliver R; Rendal, Cecilie; Ashauer, Roman

    2016-10-26

    Current environmental risk assessments (ERA) do not account explicitly for ecological factors (e.g. species composition, temperature or food availability) and multiple stressors. Assessing mixtures of chemical and ecological stressors is needed as well as accounting for variability in environmental conditions and uncertainty of data and models. Here we propose a novel probabilistic ERA framework to overcome these limitations, which focusses on visualising assessment outcomes by construct-ing and interpreting prevalence plots as a quantitative prediction of risk. Key components include environmental scenarios that integrate exposure and ecology, and ecological modelling of relevant endpoints to assess the effect of a combination of stressors. Our illustrative results demonstrate the importance of regional differences in environmental conditions and the confounding interactions of stressors. Using this framework and prevalence plots provides a risk-based approach that combines risk assessment and risk management in a meaningful way and presents a truly mechanistic alternative to the threshold approach. Even whilst research continues to improve the underlying models and data, regulators and decision makers can already use the framework and prevalence plots. The integration of multiple stressors, environmental conditions and variability makes ERA more relevant and realistic.

  17. Affective reactivity to daily stressors is associated with elevated inflammation.

    Science.gov (United States)

    Sin, Nancy L; Graham-Engeland, Jennifer E; Ong, Anthony D; Almeida, David M

    2015-12-01

    Inflammation increases the risk of chronic diseases, but the links between emotional responses to daily events and inflammation are unknown. We examined individual differences in affective reactivity to daily stressors (i.e., changes in positive and negative affect in response to stressors) as predictors of inflammatory markers interleukin-6 (IL-6) and C-reactive protein (CRP). A cross-sectional sample of 872 adults from the National Study of Daily Experiences (substudy of Midlife in the United States II) reported daily stressors and affect during telephone interviews for 8 days. Blood samples were obtained at a separate clinic visit and assayed for inflammatory markers. Multilevel models estimated trait affective reactivity slopes for each participant, which were inputted into regression models to predict inflammation. People who experienced greater decreases in positive affect on days when stressors occurred (i.e., positive affect reactivity) had elevated log IL-6, independent of demographic, physical, psychological, and behavioral factors (B = 1.12, SE = 0.45, p = .01). Heightened negative affect reactivity was associated with higher log CRP among women (p = .03) but not men (p = .57); health behaviors accounted for this association in women. Adults who fail to maintain positive affect when faced with minor stressors in everyday life appear to have elevated levels of IL-6, a marker of inflammation. Women who experience increased negative affect when faced with minor stressors may be at particular risk of elevated inflammation. These findings add to growing evidence regarding the health implications of affective reactivity to daily stressors. (c) 2015 APA, all rights reserved).

  18. Affective reactivity to daily stressors is associated with elevated inflammation

    Science.gov (United States)

    Sin, Nancy L.; Graham-Engeland, Jennifer E.; Ong, Anthony D.; Almeida, David M.

    2015-01-01

    Objective Inflammation increases the risk of chronic diseases, but the links between emotional responses to daily events and inflammation are unknown. We examined individual differences in affective reactivity to daily stressors (i.e., changes in positive and negative affect in response to stressors) as predictors of inflammatory markers interleukin-6 (IL-6) and C-reactive protein (CRP). Methods A cross-sectional sample of 872 adults from the National Study of Daily Experiences (sub-study of Midlife in the United States II) reported daily stressors and affect during telephone interviews for 8 days. Blood samples were obtained at a separate clinic visit and assayed for inflammatory markers. Multilevel models estimated trait affective reactivity slopes for each participant, which were inputted into regression models to predict inflammation. Results People who experienced greater decreases in positive affect on days when stressors occurred (i.e, positive affect reactivity) had elevated log IL-6, independent of demographic, physical, psychological, and behavioral factors (B = 1.12, SE = 0.45, p = 0.01). Heightened negative affect reactivity was associated with higher log CRP among women (p = 0.03) but not men (p = 0.57); health behaviors accounted for this association in women. Conclusions Adults who fail to maintain positive affect when faced with minor stressors in everyday life appear to have elevated levels of IL-6, a marker of inflammation. Women who experience increased negative affect when faced with minor stressors may be at particular risk of elevated inflammation. These findings add to growing evidence regarding the health implications of affective reactivity to daily stressors. PMID:26030309

  19. Stressors, locus of control, and social support as consequences of affective psychological well-being.

    Science.gov (United States)

    Daniels, K; Guppy, A

    1997-04-01

    Tests of the influence of affective psychological well-being on stressors, locus of control, and social support in a 1-month follow-up study of 210 male and 34 female British accountants is reported. There was a marginally significant association between the level of psychological symptoms and subsequent reports of intensity of quantitative workload stressors. A significant interaction between psychological symptoms and a measure of depression-enthusiasm was found to predict subsequent locus of control. The results indicate a differential pattern of associations between aspects of affective well-being and subsequent reports of social support. The results also indicate that initially more frequent stressors are associated with subsequently less intense stressors of the same type. The findings highlight the dynamic and reciprocal nature of the occupational stress process.

  20. Occupational risk perception, safety training, and injury prevention: testing a model in the Italian printing industry.

    Science.gov (United States)

    Leiter, Michael P; Zanaletti, William; Argentero, Piergiorgio

    2009-01-01

    This study examined occupational risk perception in relation to safety training and injuries. In a printing industry, 350 workers from 6 departments completed a survey. Data analysis showed significant differences in risk perceptions among departments. Differences in risk perception reflected the type of work and the injury incidents in the departments. A structural equation analysis confirmed a model of risk perception on the basis of employees' evaluation of the prevalence and lethalness of hazards as well as the control over hazards they gain from training. The number of injuries sustained was positively related to the perception of risk exposure and negatively related to evaluations about the safety training. The results highlight the importance of training interventions in increasing workers' adoption of safety procedures and prevention of injuries.

  1. The Occupancy Rate Modeling of Kendari Hotel Room using Mexican Hat Transformation and Partial Least Squares

    Directory of Open Access Journals (Sweden)

    Margaretha Ohyver

    2016-12-01

    Full Text Available Partial Least Squares (PLS method was developed in 1960 by Herman Wold. The method particularly suits with construct a regression model when the number of independent variables is many and highly collinear. The PLS can be combined with other methods, one of which is a Continuous Wavelet Transformation (CWT. By considering that the presence of outliers can lead to a less reliable model, and this kind of transformation may be required at a stage of pre-processing, the data is free of noise or outliers. Based on the previous study, Kendari hotel room occupancy rate was affected by the outlier, and it had a low value of R2. Therefore, this research aimed to obtain a good model by combining the PLS method and CWT transformation using the Mexican Hats them other wavelet of CWT. The research concludes that merging the PLS and the Mexican Hat transformation has resulted in a better model compared to the model that combined the PLS and the Haar wavelet transformation as shown in the previous study. The research shows that by changing the mother of the wavelet, the value of R2 can be improved significantly. The result provides information on how to increase the value of R2. The other advantage is the information for hotel managements to notice the age of the hotel, the maximum rates, the facilities, and the number of rooms to increase the number of visitors.

  2. Workplace Stressors and Coping Strategies Among Public Hospital Nurses in Medan, Indonesia

    Directory of Open Access Journals (Sweden)

    Achmad Fathi

    2012-08-01

    Full Text Available Background: Nursing is considered as a stressful job when compared with other jobs. Prolonged stress without effective coping strategies affects not only nurses’ occupational life but also their nursing competencies. Medan is the biggest city in Sumatera Island of Indonesia. Two tertiary public hospital nurses in this city hold the responsibility in providing excellent care to their patients. Objective: To investigate the relationships between the nurse’s workplace stressors and the coping strategies used. Method: The descriptive correlational study was conducted to examine the relationships between workplace stressors and the coping strategies used in nurses of two public hospitals in Medan. The sample size of 126 nurses was drawn from selected in-patient units. Data were collected by using self-report questionnaires and focus group interview. The majority of subjects experienced low workplace stressors, where death/dying was the most commonly reported workplace stressor followed by workload. Religion was the most commonly used coping strategy. Result: Significant correlations were found between subscales of workplace stressors and coping strategies. Most of subjects used emotion-focused and dysfunctional coping strategies rather than problem-focused coping strategies. Conclusion: The nurse administrators in the hospitals need to advocate their in order to use problem-focused coping strategies more frequent than emotion-focused and dysfunctional coping strategies when dealing with workplace stressors. Keywords: workplace stressor, coping strategy, public hospital nurses

  3. Application of a model for delivering occupational safety and health to smaller businesses: Case studies from the US.

    Science.gov (United States)

    Cunningham, Thomas R; Sinclair, Raymond

    2015-01-01

    Smaller firms are the majority in every industry in the US, and they endure a greater burden of occupational injuries, illnesses, and fatalities than larger firms. Smaller firms often lack the necessary resources for effective occupational safety and health activities, and many require external assistance with safety and health programming. Based on previous work by researchers in Europe and New Zealand, NIOSH researchers developed for occupational safety and health intervention in small businesses. This model was evaluated with several intermediary organizations. Four case studies which describe efforts to reach small businesses with occupational safety and health assistance include the following: trenching safety training for construction, basic compliance and hazard recognition for general industry, expanded safety and health training for restaurants, and fall prevention and respirator training for boat repair contractors. Successful efforts included participation by the initiator among the intermediaries' planning activities, alignment of small business needs with intermediary offerings, continued monitoring of intermediary activities by the initiator, and strong leadership for occupational safety and health among intermediaries. Common challenges were a lack of resources among intermediaries, lack of opportunities for in-person meetings between intermediaries and the initiator, and balancing the exchanges in the initiator-intermediary-small business relationships. The model offers some encouragement that initiator organizations can contribute to sustainable OSH assistance for small firms, but they must depend on intermediaries who have compatible interests in smaller businesses and they must work to understand the small business social system.

  4. Application of a model for delivering occupational safety and health to smaller businesses: Case studies from the US

    Science.gov (United States)

    Cunningham, Thomas R.; Sinclair, Raymond

    2015-01-01

    Smaller firms are the majority in every industry in the US, and they endure a greater burden of occupational injuries, illnesses, and fatalities than larger firms. Smaller firms often lack the necessary resources for effective occupational safety and health activities, and many require external assistance with safety and health programming. Based on previous work by researchers in Europe and New Zealand, NIOSH researchers developed for occupational safety and health intervention in small businesses. This model was evaluated with several intermediary organizations. Four case studies which describe efforts to reach small businesses with occupational safety and health assistance include the following: trenching safety training for construction, basic compliance and hazard recognition for general industry, expanded safety and health training for restaurants, and fall prevention and respirator training for boat repair contractors. Successful efforts included participation by the initiator among the intermediaries’ planning activities, alignment of small business needs with intermediary offerings, continued monitoring of intermediary activities by the initiator, and strong leadership for occupational safety and health among intermediaries. Common challenges were a lack of resources among intermediaries, lack of opportunities for in-person meetings between intermediaries and the initiator, and balancing the exchanges in the initiator–intermediary–small business relationships. The model offers some encouragement that initiator organizations can contribute to sustainable OSH assistance for small firms, but they must depend on intermediaries who have compatible interests in smaller businesses and they must work to understand the small business social system. PMID:26300585

  5. A multi-society examination of the impact of psychological resources on stressor-strain relationships

    NARCIS (Netherlands)

    Ralston, D.; Lee, C.H.; Perrewe, P.L.; van Deuven, C.; Vollmer, G.; Maignan, I.S.J.; Tang, M.; Wan, P.

    2010-01-01

    This paper sequentially addresses a conceptual and an empirical goal. Our conceptual goal was to develop a globally relevant model of the relationship between work role stressors and strain using conservation of resources (COR) theory as our foundation. Stressors included in the model are role

  6. Stressors in elite sport: a coach perspective.

    Science.gov (United States)

    Thelwell, Richard C; Weston, Neil J V; Greenlees, Iain A; Hutchings, Nicholas V

    2008-07-01

    We examined the varying performance and organizational stressors experienced by coaches who operate with elite athletes. Following interviews with eleven coaches, content analysis of the data revealed coaches to experience comparable numbers of performance and organizational stressors. Performance stressors were divided between their own performance and that of their athletes, while organizational stressors included environmental, leadership, personal, and team factors. The findings provide evidence that coaches experience a variety of stressors that adds weight to the argument that they should be labelled as "performers" in their own right. A variety of future research topics and applied issues are also discussed.

  7. A conceptual-practice model for occupational therapy to facilitate return to work in breast cancer patients.

    Science.gov (United States)

    Désiron, Huguette A M; Donceel, Peter; de Rijk, Angelique; Van Hoof, Elke

    2013-12-01

    Improved therapies and early detection have significantly increased the number of breast cancers survivors, leading to increasing needs regarding return to work (RTW). Occupational therapy (OT) interventions provide successful RTW assistance for other conditions, but are not validated in breast cancer. This paper aims to identify a theoretical framework for OT intervention by questioning how OT models can be used in OT interventions in RTW of breast cancer patients; criteria to be used to select these models and adaptations that would be necessary to match the OT model(s) to breast cancer patients' needs? Using research specific criteria derived from OT literature (conceptual OT-model, multidisciplinary, referring to the International Classification of functioning (ICF), RTW in breast cancer) a search in 9 electronic databases was conducted to select articles that describe conceptual OT models. A content analysis of those models complying to at least two of the selection criteria was realised. Checking for breast cancer specific issues, results were matched with literature of care-models regarding RTW in breast cancer. From the nine models initially identified, three [Canadian Model of Occupational Performance, Model of Human Occupation (MOHO), Person-Environment-Occupation-Performance model] were selected based on the selection criteria. The MOHO had the highest compliance rate with the criteria. To enhance usability in breast cancer, some adaptations are needed. No OT model to facilitate RTW in breast cancer could be identified, indicating a need to fill this gap. Individual and societal needs of breast cancer patients can be answered by using a MOHO-based OT model, extended with indications for better treatment, work-outcomes and longitudinal process factors.

  8. ICT and OTs: a model of information and communication technology acceptance and utilisation by occupational therapists.

    Science.gov (United States)

    Schaper, Louise K; Pervan, Graham P

    2007-06-01

    There is evidence to suggest that health professionals are reluctant to accept and utilise information and communication technologies (ICT) and concern is growing within health informatics research that this is contributing to the lag in adoption and utilisation of ICT across the health sector. Technology acceptance research within the field of information systems has been limited in its application to health and there is a concurrent need to develop and gain empirical support for models of technology acceptance within health and to examine acceptance and utilisation issues amongst health professionals to improve the success of information system implementation in this arena. This paper outlines a project that examines ICT acceptance and utilisation by Australian occupational therapists. It describes the theoretical basis behind the development of a research model and the methodology being employed to empirically validate the model using substantial quantitative, qualitative and longitudinal data. Preliminary results from Phase II of the study are presented. The theoretical significance of this work is that it uses a thoroughly constructed research model, with potentially the largest sample size ever tested, to extend technology acceptance research into the health sector.

  9. Timing anthropogenic stressors to mitigate their impact on marine ecosystem resilience.

    Science.gov (United States)

    Wu, Paul Pao-Yen; Mengersen, Kerrie; McMahon, Kathryn; Kendrick, Gary A; Chartrand, Kathryn; York, Paul H; Rasheed, Michael A; Caley, M Julian

    2017-11-02

    Better mitigation of anthropogenic stressors on marine ecosystems is urgently needed to address increasing biodiversity losses worldwide. We explore opportunities for stressor mitigation using whole-of-systems modelling of ecological resilience, accounting for complex interactions between stressors, their timing and duration, background environmental conditions and biological processes. We then search for ecological windows, times when stressors minimally impact ecological resilience, defined here as risk, recovery and resistance. We show for 28 globally distributed seagrass meadows that stressor scheduling that exploits ecological windows for dredging campaigns can achieve up to a fourfold reduction in recovery time and 35% reduction in extinction risk. Although the timing and length of windows vary among sites to some degree, global trends indicate favourable windows in autumn and winter. Our results demonstrate that resilience is dynamic with respect to space, time and stressors, varying most strongly with: (i) the life history of the seagrass genus and (ii) the duration and timing of the impacting stress.

  10. Personality and Stressor-Related Affect

    Science.gov (United States)

    Leger, Kate A.; Charles, Susan T.; Turiano, Nicholas A.; Almeida, David M.

    2015-01-01

    Greater increases in negative affect and greater decreases in positive affect on days stressors occur portend poorer mental and physical health years later. Although personality traits influence stressor-related affect, only neuroticism and extraversion among the Big Five personality traits have been examined in any detail. Moreover, personality traits may shape how people appraise daily stressors, yet few studies have examined how stressor-related appraisals may account for associations between personality and stressor-related affect. Two studies used participants (N=2022, age 30–84) from the National Study of Daily Experiences II (NSDE II) to examine the associations between Big Five personality traits and stressor-related affect, in addition to how appraisals may account for these relationships. Results from Study 1 indicate that higher levels of extraversion, conscientiousness, and openness to experience, and lower levels of neuroticism, are related to less stressor-related negative affect. Only agreeableness was associated with stressor-related positive affect, such that higher levels were related to greater decreases in positive affect on days stressors occur. The second study found that stressor-related appraisals partially accounted for the significant associations between stressor-related negative affect and personality. Implications for these findings in relation to how personality may influence physical and emotional health are discussed. PMID:26796984

  11. Use of multispecies occupancy models to evaluate the response of bird communities to forest degradation associated with logging.

    Science.gov (United States)

    Carrillo-Rubio, Eduardo; Kéry, Marc; Morreale, Stephen J; Sullivan, Patrick J; Gardner, Beth; Cooch, Evan G; Lassoie, James P

    2014-08-01

    Forest degradation is arguably the greatest threat to biodiversity, ecosystem services, and rural livelihoods. Therefore, increasing understanding of how organisms respond to degradation is essential for management and conservation planning. We were motivated by the need for rapid and practical analytical tools to assess the influence of management and degradation on biodiversity and system state in areas subject to rapid environmental change. We compared bird community composition and size in managed (ejido, i.e., communally owned lands) and unmanaged (national park) forests in the Sierra Tarahumara region, Mexico, using multispecies occupancy models and data from a 2-year breeding bird survey. Unmanaged sites had on average higher species occupancy and richness than managed sites. Most species were present in low numbers as indicated by lower values of detection and occupancy associated with logging-induced degradation. Less than 10% of species had occupancy probabilities >0.5, and degradation had no positive effects on occupancy. The estimated metacommunity size of 125 exceeded previous estimates for the region, and sites with mature trees and uneven-aged forest stand characteristics contained the highest species richness. Higher estimation uncertainty and decreases in richness and occupancy for all species, including habitat generalists, were associated with degraded young, even-aged stands. Our findings show that multispecies occupancy methods provide tractable measures of biodiversity and system state and valuable decision support for landholders and managers. These techniques can be used to rapidly address gaps in biodiversity information, threats to biodiversity, and vulnerabilities of species of interest on a landscape level, even in degraded or fast-changing environments. Moreover, such tools may be particularly relevant in the assessment of species richness and distribution in a wide array of habitats. © 2014 Society for Conservation Biology.

  12. Nurses′ workplace stressors and coping strategies

    Directory of Open Access Journals (Sweden)

    Vickie A Lambert

    2008-01-01

    Full Text Available Prior research has suggested that nurses, regardless of workplace or culture, are confronted with a variety of stressors. As the worldwide nursing shortage increases, the aged population becomes larger, there is an increase in the incidence of chronic illnesses and technology continues to advance, nurses continually will be faced with numerous workplace stressors. Thus, nurses, especially palliative care nurses, need to learn how to identify their workplace stressors and to cope effectively with these stressors to attain and maintain both their physical and mental health. This article describes workplace stressors and coping strategies, compares and contrasts cross-cultural literature on nurses′ workplace stressors and coping strategies, and delineates a variety of stress management activities that could prove helpful for contending with stressors in the workplace.

  13. Development and validation of rear impact computer simulation model of an adult manual transit wheelchair with a seated occupant.

    Science.gov (United States)

    Salipur, Zdravko; Bertocci, Gina

    2010-01-01

    It has been shown that ANSI WC19 transit wheelchairs that are crashworthy in frontal impact exhibit catastrophic failures in rear impact and may not be able to provide stable seating support and thus occupant protection for the wheelchair occupant. Thus far only limited sled test and computer simulation data have been available to study rear impact wheelchair safety. Computer modeling can be used as an economic and comprehensive tool to gain critical knowledge regarding wheelchair integrity and occupant safety. This study describes the development and validation of a computer model simulating an adult wheelchair-seated occupant subjected to a rear impact event. The model was developed in MADYMO and validated rigorously using the results of three similar sled tests conducted to specifications provided in the draft ISO/TC 173 standard. Outcomes from the model can provide critical wheelchair loading information to wheelchair and tiedown manufacturers, resulting in safer wheelchair designs for rear impact conditions. (c) 2009 IPEM. Published by Elsevier Ltd. All rights reserved.

  14. Spatial clustering and halo occupation distribution modelling of local AGN via cross-correlation measurements with 2MASS galaxies

    Science.gov (United States)

    Krumpe, Mirko; Miyaji, Takamitsu; Coil, Alison L.; Aceves, Hector

    2018-02-01

    We present the clustering properties and halo occupation distribution (HOD) modelling of very low redshift, hard X-ray-detected active galactic nuclei (AGN) using cross-correlation function measurements with Two-Micron All Sky Survey galaxies. Spanning a redshift range of 0.007 2MASS galaxies.

  15. Development and validation of a prediction model for long-term sickness absence based on occupational health survey variables

    NARCIS (Netherlands)

    Roelen, Corne; Thorsen, Sannie; Heymans, Martijn; Twisk, Jos; Bultmann, Ute; Bjorner, Jakob

    2018-01-01

    Purpose: The purpose of this study is to develop and validate a prediction model for identifying employees at increased risk of long-term sickness absence (LTSA), by using variables commonly measured in occupational health surveys. Materials and methods: Based on the literature, 15 predictor

  16. Model versus Military Pilot: A Mixed-Methods Study of Adolescents' Attitudes toward Women in Varied Occupations

    Science.gov (United States)

    Daniels, Elizabeth A.; Sherman, Aurora M.

    2016-01-01

    Using an experimental methodology, the present study investigated adolescents' attitudes toward media images of women in non-appearance-focused (CEO and military pilot) and appearance-focused occupations (model and actor). One hundred adolescent girls and 76 adolescent boys provided ratings of likability, competence, and similarity to self after…

  17. Collaborative Occupational Therapy: Teachers' Impressions of the Partnering for Change (P4C) Model.

    Science.gov (United States)

    Wilson, A L; Harris, S R

    2018-05-01

    Occupational therapists (OTs) often face barriers when trying to collaborate with teachers in school-based settings. Partnering for change (P4C), a collaborative practice model designed to support children with developmental coordination disorder, could potentially support all students with special needs. Therefore, the aim of this study was to explore how teachers experience OT services delivered using the P4C model to support children with a variety of special needs. P4C was implemented at one elementary school in Courtenay, British Columbia. Eleven teachers participated in two focus groups and a one-on-one interview to gather descriptive, qualitative data. Grounded theory techniques were used for data analysis. Four themes (collaborating in the thick of it all, learning and taking risks, managing limited time and resources, and appreciating responsive OT support) represented teachers' experiences of P4C. Teachers strongly preferred collaborative OT services based on the P4C model. Students with a variety of special needs were supported within their classrooms as teachers learned new strategies from the OT and found ways to embed these strategies into their daily routines.

  18. A structural regression model for relationship between indoor air quality with dissatisfaction of occupants in education environment

    Science.gov (United States)

    Hosseini, Hamid Reza; Yunos, Mohd Yazid Mohd; Ismail, Sumarni; Yaman, Maheran

    2017-12-01

    This paper analysis the effects of indoor air elements on the dissatisfaction of occupants in education of environments. Tries to find the equation model for increasing the comprehension about these affects and optimizes satisfaction of occupants about indoor environment. Subsequently, increase performance of students, lecturers and staffs. As the method, a satisfaction questionnaire (SQ) and measuring environment elements (MEE) was conducted, 143 respondents at five classrooms, four staff rooms and five lectures rooms were considered. Temperature, air velocity and humidity (TVH) were used as independent variables and dissatisfaction as dependent variable. The hypothesis was tested for significant relationship between variables, and analysis was applied. Results found that indoor air quality presents direct effects on dissatisfaction of occupants and indirect effects on performance and the highest effects fallowed by temperature. These results may help to optimize the quality of efficiency and effectiveness in education environments.

  19. Time-dependent occupation numbers in reduced-density-matrix-functional theory: Application to an interacting Landau-Zener model

    International Nuclear Information System (INIS)

    Requist, Ryan; Pankratov, Oleg

    2011-01-01

    We prove that if the two-body terms in the equation of motion for the one-body reduced density matrix are approximated by ground-state functionals, the eigenvalues of the one-body reduced density matrix (occupation numbers) remain constant in time. This deficiency is related to the inability of such an approximation to account for relative phases in the two-body reduced density matrix. We derive an exact differential equation giving the functional dependence of these phases in an interacting Landau-Zener model and study their behavior in short- and long-time regimes. The phases undergo resonances whenever the occupation numbers approach the boundaries of the interval [0,1]. In the long-time regime, the occupation numbers display correlation-induced oscillations and the memory dependence of the functionals assumes a simple form.

  20. Bus use and older people: a literature review applying the Person-Environment-Occupation model in macro practice.

    Science.gov (United States)

    Broome, Kieran; McKenna, Kryss; Fleming, Jennifer; Worrall, Linda

    2009-03-01

    The same reasons that prompt older people to give up driving can also result in difficulties with accessing public transport. Difficulties using public transport can limit older people's participation in society, thereby impacting negatively on their health. Focusing on public buses, this review explicates the link between bus usability and the health of older people and frames existing evidence on bus usability issues. The Person-Environment-Occupation (PEO) model offers a framework by which bus usability can be assessed. A combination of person-centred, environmental, and occupation-related factors, including bus design, service provision and performance, information, and the attitudes of staff and the community, impact on older people's ability to catch buses. More systematic research needs to take place in order to develop a comprehensive understanding of bus usability. Occupational therapy has a key role to play in conceptualizing, implementing, and evaluating improvements in bus usability for older people.

  1. Work stressors and impaired sleep: rumination as a mediator.

    Science.gov (United States)

    Berset, Martial; Elfering, Achim; Lüthy, Stefan; Lüthi, Simon; Semmer, Norbert K

    2011-04-01

    An association between stress at work and impaired sleep is theoretically plausible and supported by empirical evidence. The current study's main aim was to investigate how the influence of stressors is carried over into the evening and the night. We assume that this relationship is mediated by perseverative cognitions. We tested this assumption in two cross-sectional samples with structural equation modeling, using bootstrapped standard errors to test for significance. Effort–reward imbalance and time pressure were used as stressors, and rumination as a measure for perseverative cognitions. Results show that the stressors are related to perseverative cognitions, and these are related to impaired sleep in both samples. Indirect effects are significant in both samples. With rumination controlled, direct effects of stressors on sleep are only significant in one out of four cases. Thus, there is full mediation in three out of four cases, and partial mediation in the fourth one. Our results underscore the notion that perseverative cognitions are crucial for transferring negative effects of work stressors into private life, including sleep, thus hindering individuals to successfully recover.

  2. Changes of individual perception in psychosocial stressors related to German reunification in 1989/1990 and cardiovascular risk factors and cardiovascular diseases in a population-based study in East Germany.

    Science.gov (United States)

    Bohley, Stefanie; Kluttig, Alexander; Werdan, Karl; Nuding, Sebastian; Greiser, Karin Halina; Kuss, Oliver; Markus, Marcello Ricardo Paulista; Schmidt, Carsten Oliver; Völzke, Henry; Krabbe, Christine; Haerting, Johannes

    2016-01-04

    Aim was to examine the relationship between individually perceived changes in psychosocial stressors associated with German reunification and cardiovascular effects. We hypothesised that higher levels of psychosocial stress related to German reunification were associated with an increase in cardiovascular risk factors and cardiovascular diseases (CVDs). Cross-sectional data from 2 cohort studies in East Germany were used: Cardiovascular Disease, Living and Ageing in Halle Study (CARLA), and Study of Health in Pomerania (SHIP). 2 populations in East Germany. CARLA study: 1779 participants, aged 45-83 years at baseline (812 women), SHIP study: 4308 participants, aged 20-79 years at baseline (2193 women). Psychosocial stressors related to reunification were operationalised by the Reunification Stress Index (RSI; scale from 0 to 10). This index was composed of questions that were related to individually perceived changes in psychosocial stressors (occupational, financial and personal) after reunification. To examine the associations between the RSI and each stressor separately with cardiovascular risk factors and CVD, regression models were used. RSI was associated with CVD in women (RR=1.15, 95% CI 1.00 to 1.33). Cardiovascular risk factors were associated with RSI for both men and women, with strongest associations between RSI and diabetes in women (RR=1.10, 95% CI 1.01 to 1.20) and depressive disorders in men (RR=1.15, 95% CI 1.07 to 2.77). The change in occupational situation related to reunification was the major contributing psychosocial stressor. We observed a strong association with CVD in women who experienced occupational deterioration after reunification (RR=4.04, 95% CI 1.21 to 13.43). Individually perceived deterioration of psychosocial stressors (occupational, financial and personal) related to German reunification was associated with cardiovascular risk factors and CVD. The associations were stronger for women than for men. An explanation for these

  3. Associations of financial stressors and physical intimate partner violence perpetration.

    Science.gov (United States)

    Schwab-Reese, Laura M; Peek-Asa, Corinne; Parker, Edith

    2016-12-01

    Contextual factors, such as exposure to stressors, may be antecedents to IPV perpetration. These contextual factors may be amenable to modification through intervention and prevention. However, few studies have examined specific contextual factors. To begin to address this gap, we examined the associations between financial stressors and three types of physical IPV perpetration. This analysis used data from Wave IV of The National Longitudinal Study of Adolescent to Adult Health. We used logistic regression to examine the associations of financial stressors and each type of IPV (minor, severe, causing injury), and multinomial logit regression to examine the associations of financial stressors and patterns of co-occurring types of IPV perpetration (only minor; only severe; minor and severe; minor, severe, and causing injury; compared with no perpetration). Fewer men perpetrated threats/minor physical IPV (6.7 %) or severe physical IPV (3.4 %) compared with women (11.4 % and 8.8 %, respectively). However, among physical IPV perpetrators, a higher percentage of men (32.0 %) than women (21.0 %) reported their partner was injured as a result of the IPV. In logistic regression models of each type of IPV perpetration, both the number of stressors experienced and several types of financial stressors were associated with perpetrating each type of IPV. Utilities nonpayment, housing nonpayment, food insecurity, and no phone service were associated with increased odds of perpetrating each form of IPV in adjusted analysis. Eviction was associated with perpetrating severe physical IPV but not threats/minor IPV or IPV causing injury. In multinomial logit regression comparing patterns of IPV perpetration to perpetrating no physical IPV, the relationships of financial stressors were less consistent. Food insecurity was associated with perpetrating only minor physical IPV. Comparatively, overall number of financial stressors and four types of financial stressors (utilities

  4. Teachers' Occupation-Specific Work-Family Conflict

    Science.gov (United States)

    Cinamon, Rachel Gali; Rich, Yisrael; Westman, Mina

    2007-01-01

    To expand work-family conflict (WFC) research to specific occupations, this study investigated how work and family generic and occupation-specific stressors and support variables related to family interfering with work (F [right arrow] W) and work interfering with family (W [right arrow] F) among 230 Israeli high school teachers. Further expanding…

  5. Translational Modeling in Schizophrenia: Predicting Human Dopamine D2 Receptor Occupancy.

    Science.gov (United States)

    Johnson, Martin; Kozielska, Magdalena; Pilla Reddy, Venkatesh; Vermeulen, An; Barton, Hugh A; Grimwood, Sarah; de Greef, Rik; Groothuis, Geny M M; Danhof, Meindert; Proost, Johannes H

    2016-04-01

    To assess the ability of a previously developed hybrid physiology-based pharmacokinetic-pharmacodynamic (PBPKPD) model in rats to predict the dopamine D2 receptor occupancy (D2RO) in human striatum following administration of antipsychotic drugs. A hybrid PBPKPD model, previously developed using information on plasma concentrations, brain exposure and D2RO in rats, was used as the basis for the prediction of D2RO in human. The rat pharmacokinetic and brain physiology parameters were substituted with human population pharmacokinetic parameters and human physiological information. To predict the passive transport across the human blood-brain barrier, apparent permeability values were scaled based on rat and human brain endothelial surface area. Active efflux clearance in brain was scaled from rat to human using both human brain endothelial surface area and MDR1 expression. Binding constants at the D2 receptor were scaled based on the differences between in vitro and in vivo systems of the same species. The predictive power of this physiology-based approach was determined by comparing the D2RO predictions with the observed human D2RO of six antipsychotics at clinically relevant doses. Predicted human D2RO was in good agreement with clinically observed D2RO for five antipsychotics. Models using in vitro information predicted human D2RO well for most of the compounds evaluated in this analysis. However, human D2RO was under-predicted for haloperidol. The rat hybrid PBPKPD model structure, integrated with in vitro information and human pharmacokinetic and physiological information, constitutes a scientific basis to predict the time course of D2RO in man.

  6. Stressor-related drinking and future alcohol problems among university students.

    Science.gov (United States)

    Russell, Michael A; Almeida, David M; Maggs, Jennifer L

    2017-09-01

    Research using daily designs has shown that daily stressors (i.e., conflict, school/work demands) are associated with alcohol use, and that the strength of within-person links between stressors and alcohol use differs from person to person. However, to our knowledge no research has tested whether individual differences in stressor-related drinking-characterized by within-person associations between daily stressors and drinking-predict risk for future alcohol problems, a relationship suggested by theoretical models. The current study used an Internet-based daily diary design among 744 university students to (a) examine the day-level relationship between stressors and alcohol use during the first 3 years of college, and (b) test whether individual differences in the stressor-drinking relationship, captured by person-specific slopes generated from multilevel models, predicted alcohol problems as measured by the Alcohol Use Disorders Identification Test (AUDIT) in the fourth year of college. Results showed that students were more likely to drink on days with many versus fewer stressors, and on drinking days, students consumed more drinks with each additional stressor they experienced. Next, using individual multilevel modeling slopes as predictors, we found that students whose odds of drinking alcohol increased more sharply on high- versus low-stressor days (steeper slopes) had more severe AUDIT alcohol problems in the fourth year than students whose drinking odds increased less sharply (flatter slopes). Findings highlight the role of daily stressors in college student drinking and suggest stressor-related drinking as a risk factor for future alcohol problems. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  7. Effect of occupational mobility and health status on life satisfaction of Chinese residents of different occupations: logistic diagonal mobility models analysis of cross-sectional data on eight Chinese provinces

    Science.gov (United States)

    2014-01-01

    Background Life satisfaction research in China is in development, requiring new perspectives for enrichment. In China, occupational mobility is accompanied by changes in economic liberalization and the emergence of occupational stratification. On the whole, however, occupational mobility has rarely been used as an independent variable. Health status is always used as the observed or dependent variable in studies of the phenomenon and its influencing factors. A research gap still exists for enriching this field. Methods The data used in this study were obtained from the China Health and Nutrition Survey (CHNS). The study included nine provinces in China. The survey was conducted from 1989 to 2009.Every survey involved approximately 4400 families or 19,000 individual samples and parts of community data. Results First, we built a 5 × 5 social mobility table and calculated life satisfaction of Chinese residents of different occupations in each table. Second, gender, age, marital status, education level, annual income and hukou, health status, occupational mobility were used as independent variables. Lastly, we used logistic diagonal mobility models to analyze the relationship between life satisfaction and the variables. Model 1 was the basic model, which consisted of the standard model and controlled variables and excluded drift variables. Model 2 was the total model, which consisted of all variables of interest in this study. Model 3 was the screening model, which excluded the insignificant drift effect index in Model 2. Conclusion From the perspective of the analysis of controlled variables, health conditions, direction, and distance of occupational mobility significantly affected life satisfaction of Chinese residents of different occupations. (1) From the perspective of health status, respondents who have not been sick or injured had better life satisfaction than those who had been sick or injured. (2) From the perspective of occupational mobility direction

  8. Effect of occupational mobility and health status on life satisfaction of Chinese residents of different occupations: logistic diagonal mobility models analysis of cross-sectional data on eight Chinese provinces.

    Science.gov (United States)

    Liang, Ying; Lu, Peiyi

    2014-02-08

    Life satisfaction research in China is in development, requiring new perspectives for enrichment. In China, occupational mobility is accompanied by changes in economic liberalization and the emergence of occupational stratification. On the whole, however, occupational mobility has rarely been used as an independent variable. Health status is always used as the observed or dependent variable in studies of the phenomenon and its influencing factors. A research gap still exists for enriching this field. The data used in this study were obtained from the China Health and Nutrition Survey (CHNS). The study included nine provinces in China. The survey was conducted from 1989 to 2009.Every survey involved approximately 4400 families or 19,000 individual samples and parts of community data. First, we built a 5 × 5 social mobility table and calculated life satisfaction of Chinese residents of different occupations in each table. Second, gender, age, marital status, education level, annual income and hukou, health status, occupational mobility were used as independent variables. Lastly, we used logistic diagonal mobility models to analyze the relationship between life satisfaction and the variables. Model 1 was the basic model, which consisted of the standard model and controlled variables and excluded drift variables. Model 2 was the total model, which consisted of all variables of interest in this study. Model 3 was the screening model, which excluded the insignificant drift effect index in Model 2. From the perspective of the analysis of controlled variables, health conditions, direction, and distance of occupational mobility significantly affected life satisfaction of Chinese residents of different occupations. (1) From the perspective of health status, respondents who have not been sick or injured had better life satisfaction than those who had been sick or injured. (2) From the perspective of occupational mobility direction, the coefficients of occupational

  9. Multiple stressors for oceanic primary production

    KAUST Repository

    Agusti, Susana

    2015-12-15

    Marine ecosystems are increasingly exposed to stress factors of anthropogenic origin that change their function, structure and services they deliver society. Climate change occurs simultaneously with other changes in the environment acting jointly in a context of global environmental change. For oceanic phytoplankton communities, the research conducted so far has identified stress factors associated with global change and their impact individually (warming, acidification, increased UVB radiation, pollutants). But when several stressors act simultaneously interactions and responses are not equal to the sum of individual impacts, but may have synergistic effects (the effects are multiplied) or antagonistic (cancel out the effects) that hinder predictions of the vulnerability of ecosystems to global change. Here we will examine the vulnerability of oceanic primary producers to the accumulation of different stressors associated with global change. The trend for autotrophic picoplankton to increase with temperature in the ocean has led to predictions that autotrophic picoplankton abundance will increase with warming. However, it is documented a trend towards a decline in productivity, due to declined autotroph biomass and production with warming and the associated stratification in the subtropical ocean. Models predicting an increase in abundance are in contradiction with the reported decrease in productivity in several oceanic areas, and associate oligotrophication. Here we perform a global study to analyze the relationships of autotrophic picoplankton with oceanic temperature, nutrients, underwater light and ultraviolet B (UVB) radiation, and productivity. We built a model to project the future changes of autotrophic picoplankton considering multiple environmental changes in future climate scenarios for the subtropical gyres. We considered increased water temperature, and associated changes in productivity and underwater light and UVB. The model show that warming and

  10. Multiple stressors for oceanic primary production

    KAUST Repository

    Agusti, Susana; Llabré s, Moira; Lubiá n, Luis M.; Moreno-Ostos, Enrique; Estrada, Marta; Duarte, Carlos M.; Cerezo, Maria I.

    2015-01-01

    Marine ecosystems are increasingly exposed to stress factors of anthropogenic origin that change their function, structure and services they deliver society. Climate change occurs simultaneously with other changes in the environment acting jointly in a context of global environmental change. For oceanic phytoplankton communities, the research conducted so far has identified stress factors associated with global change and their impact individually (warming, acidification, increased UVB radiation, pollutants). But when several stressors act simultaneously interactions and responses are not equal to the sum of individual impacts, but may have synergistic effects (the effects are multiplied) or antagonistic (cancel out the effects) that hinder predictions of the vulnerability of ecosystems to global change. Here we will examine the vulnerability of oceanic primary producers to the accumulation of different stressors associated with global change. The trend for autotrophic picoplankton to increase with temperature in the ocean has led to predictions that autotrophic picoplankton abundance will increase with warming. However, it is documented a trend towards a decline in productivity, due to declined autotroph biomass and production with warming and the associated stratification in the subtropical ocean. Models predicting an increase in abundance are in contradiction with the reported decrease in productivity in several oceanic areas, and associate oligotrophication. Here we perform a global study to analyze the relationships of autotrophic picoplankton with oceanic temperature, nutrients, underwater light and ultraviolet B (UVB) radiation, and productivity. We built a model to project the future changes of autotrophic picoplankton considering multiple environmental changes in future climate scenarios for the subtropical gyres. We considered increased water temperature, and associated changes in productivity and underwater light and UVB. The model show that warming and

  11. Relationship between occupational stress and cardiovascular diseases risk factors in drivers.

    Science.gov (United States)

    Biglari, Hamed; Ebrahimi, Mohammad Hossein; Salehi, Maryam; Poursadeghiyan, Mohsen; Ahmadnezhad, Iman; Abbasi, Milad

    2016-11-18

    Of all work stressors, occupational stress is the leading cause of many disorders among workers. Drivers are classified as a high risk group for work related stress. This study set out to determine the relationship between risk factors of cardiovascular diseases and occupational stress among drivers. Two hundred and twenty two Ilam's intercity drivers were selected for the study. For measuring work stress, the Osipow work stress questionnaire was used. After a 10-h fasting period, systolic and diastolic blood pressure was recorded. Intravenous blood samples were taken to determine cholesterol, triglyceride and blood glucose levels. The independent samples t-test and Pearson's correlation test were used to assess the relationship between variables and occupational stress. Seventy-one percent of the intercity drivers suffered from average to acute stress, and 3.1% of them suffered from acute stress. There was no significant relationship between occupational stress and diastolic blood pressure (p = 0.254) among the drivers. Nevertheless, the Pearson's correlation test demonstrated a strong relationship between work stress and blood glucose (p stress were observed in the Ilam's intercity drivers. Occupational stress may have effect on blood glucose levels but the results did not suggest a considerable relationship between risk factors of cardiovascular diseases and occupational stress among intercity drivers. Int J Occup Med Environ Health 2016;29(6):895-901. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  12. Occupational asthma caused by samba (Triplochiton scleroxylon) wood dust in a professional maker of wooden models of airplanes: a case study.

    Science.gov (United States)

    Krawczyk-Szulc, Patrycja; Wiszniewska, Marta; Pałczyński, Cezary; Nowakowska-Świrta, Ewa; Kozak, Anna; Walusiak-Skorupa, Jolanta

    2014-06-01

    Wood dust is a known occupational allergen that may induce, in exposed workers, respiratory diseases including asthma and allergic rhinitis. Samba (obeche, Triplochiton scleroxylon) is a tropical tree, which grows in West Africa, therefore, Polish workers are rarely exposed to it. This paper describes a case of occupational asthma caused by samba wood dust. The patient with suspicion of occupational asthma due to wood dust was examined at the Department of Occupational Diseases and Clinical Toxicology in the Nofer Institute of Occupational Medicine. Clinical evaluation included: analysis of occupational history, skin prick tests (SPT) to common and occupational allergens, determination of serum specific IgE to occupational allergens, serial spirometry measurements, metacholine challenge test and specific inhalation challenge test with samba dust SPT and specific serum IgE assessment revealed sensitization to common and occupational allergens including samba. Spirometry measurements showed mild obstruction. Metacholine challenge test revealed a high level of bronchial hyperactivity. Specific inhalation challenge test was positive and cellular changes in nasal lavage and induced sputum confirmed allergic reaction to samba. IgE mediated allergy to samba wood dust was confirmed. This case report presents the first documented occupational asthma and rhinitis due to samba wood dust in wooden airplanes model maker in Poland.

  13. Occupational asthma caused by samba (Triplochiton scleroxylon wood dust in a professional maker of wooden models of airplanes: A case study

    Directory of Open Access Journals (Sweden)

    Patrycja Krawczyk-Szulc

    2014-08-01

    Full Text Available Objectives: Wood dust is a known occupational allergen that may induce, in exposed workers, respiratory diseases including asthma and allergic rhinitis. Samba (obeche, Triplochiton scleroxylon is a tropical tree, which grows in West Africa, therefore, Polish workers are rarely exposed to it. This paper describes a case of occupational asthma caused by samba wood dust. Material and Methods: The patient with suspicion of occupational asthma due to wood dust was examined at the Department of Occupational Diseases and Clinical Toxicology in the Nofer Institute of Occupational Medicine. Clinical evaluation included: analysis of occupational history, skin prick tests (SPT to common and occupational allergens, determination of serum specific IgE to occupational allergens, serial spirometry measurements, metacholine challenge test and specific inhalation challenge test with samba dust. Results: SPT and specific serum IgE assessment revealed sensitization to common and occupational allergens including samba. Spirometry measurements showed mild obstruction. Metacholine challenge test revealed a high level of bronchial hyperactivity. Specific inhalation challenge test was positive and cellular changes in nasal lavage and induced sputum confirmed allergic reaction to samba. Conclusions: IgE mediated allergy to samba wood dust was confirmed. This case report presents the first documented occupational asthma and rhinitis due to samba wood dust in wooden airplanes model maker in Poland.

  14. Occupational cancer

    International Nuclear Information System (INIS)

    Alderson, M.

    1986-01-01

    This book aims to review the occurrence and causes of occupational cancer and is aimed at assisting medical and safety staff, management and health and safety representatives. It is presented in the following chapters: 1) Epidemiological method 2) Agents causing occupationally induced cancer, including radiation 3) Occupations associated with risk of cancer 4) Aetiology of cancer 5) Control of occupationally induced cancer, research, prevention, legislation, national and international bodies, control of specific occupational carcinogens, including irradiation. (U.K.)

  15. Reconceptualizing synergism and antagonism among multiple stressors

    OpenAIRE

    Piggott, Jeremy J; Townsend, Colin R; Matthaei, Christoph D

    2015-01-01

    The potential for complex synergistic or antagonistic interactions between multiple stressors presents one of the largest uncertainties when predicting ecological change but, despite common use of the terms in the scientific literature, a consensus on their operational definition is still lacking. The identification of synergism or antagonism is generally straightforward when stressors operate in the same direction, but if individual stressor effects oppose each other, the definition of syner...

  16. 76 FR 31453 - Special Conditions: Gulfstream Model GVI Airplane; Single-Occupant Side-Facing Seats

    Science.gov (United States)

    2011-06-01

    ... or furnishing that will support the pelvis, upper arm, chest, and head of an occupant seated next to.... 3. Thoracic Trauma: Thoracic trauma index (TTI) injury criterion must be substantiated by dynamic...

  17. From eyeballing to statistical modelling : methods for assessment of occupational exposure

    NARCIS (Netherlands)

    Kromhout, H.

    1994-01-01

    In this thesis methods for assessment of occupational exposure are evaluated and developed. These methods range from subjective methods (qualitative and semiquantitative) to more objective quantitative methods based on actual measurement of personal exposure to chemical and physical

  18. Occupational health purchasing behaviour by SMEs--a new theoretical model.

    Science.gov (United States)

    Harrison, J; Woods, A; Dickson, K

    2013-10-01

    Factors influencing corporate decisions to purchase occupational health (OH) are unknown. To assist the marketing of OH services to small- and medium-sized enterprises (SMEs) by characterizing purchasing behaviour. We developed a 2×2 model, based on published studies, to describe OH purchasing behaviour by SMEs. We tested the model by analysis of responses to a cross-sectional market research survey carried out in November 2007. The companies surveyed were SMEs employing 30-250 employees, within the localities of five UK National Health Service OH services: West London, Buckinghamshire, Cambridge, Portsmouth and York. We chose a sample representative of all SMEs for each location. The survey explored knowledge of OH and the perceived importance of a variety of services. We obtained responses from 387 companies (19%); 81% indicated that they knew about OH and 24% had purchased OH services. OH was rated 'very important' by 35%, and 65% rated it as 'quite' or 'very important'. Sickness absence and its business impact were monitored by 89%. Enterprises claiming OH understanding were significantly more likely to purchase OH services (odds ratio [OR] 3.5, 95% confidence interval [CI] 1.6-8.0). Companies employing fewer than 90 employees were significantly less likely to purchase such services than larger ones (OR 0.17, 95% CI 0.09-0.3). OH knowledge and company size are key determinants of SME purchasing behaviour. Our findings support our proposed theoretical model. However, more research could explore claimed knowledge of OH with respect to the proposed purchaser types and business benefits.

  19. The Halo Occupation Distribution of obscured quasars: revisiting the unification model

    Science.gov (United States)

    Mitra, Kaustav; Chatterjee, Suchetana; DiPompeo, Michael A.; Myers, Adam D.; Zheng, Zheng

    2018-06-01

    We model the projected angular two-point correlation function (2PCF) of obscured and unobscured quasars selected using the Wide-field Infrared Survey Explorer (WISE), at a median redshift of z ˜ 1 using a five parameter Halo Occupation Distribution (HOD) parametrization, derived from a cosmological hydrodynamic simulation by Chatterjee et al. The HOD parametrization was previously used to model the 2PCF of optically selected quasars and X-ray bright active galactic nuclei (AGNs) at z ˜ 1. The current work shows that a single HOD parametrization can be used to model the population of different kinds of AGN in dark matter haloes suggesting the universality of the relationship between AGN and their host dark matter haloes. Our results show that the median halo mass of central quasar hosts increases from optically selected (4.1^{+0.3}_{-0.4} × 10^{12} h^{-1} M_{⊙}) and infra-red (IR) bright unobscured populations (6.3^{+6.2}_{-2.3} × 10^{12} h^{-1} M_{⊙}) to obscured quasars (10.0^{+2.6}_{-3.7} × 10^{12} h^{-1} M_{⊙}), signifying an increase in the degree of clustering. The projected satellite fractions also increase from optically bright to obscured quasars and tend to disfavour a simple `orientation only' theory of active galactic nuclei unification. Our results also show that future measurements of the small-scale clustering of obscured quasars can constrain current theories of galaxy evolution where quasars evolve from an IR-bright obscured phase to the optically bright unobscured phase.

  20. Spatial interaction models from Irish commuting data: variations in trip length by occupation and gender

    Science.gov (United States)

    O'Kelly, Morton E.; Niedzielski, Michael A.; Gleeson, Justin

    2012-10-01

    Core and peripheral contrasts in journey-to-work trip length can be interpreted as imputing the relative value of origin and destination accessibility (yielding theoretical proxies for rent and wages). Because the main variables are shown to be critically dependent on spatial structure, they may be interpreted as showing the shadow prices due to comparative location. There is also a unifying connection between these results and the existing literature on many dimensions: rent gradients, accessibility, and emissivity. In an empirical example, the advantages of a panoramic view of national commuting statistics are shown, using an Irish data set. Variations in the rates of participation in trip making by location, occupation, and gender are examined. Places that emit more trips than would be expected from their relative location are identified. Further, examining ways in which such emissivity is sensitive to a change in trip length highlights the regions where trips could possibly be adjusted to produce a shorter average trip length or which might be especially sensitive to reduction in employment. A careful reinterpretation of one of the key outputs from a calibrated spatial interaction model is shown to be consistent with the declining rent gradient expected from Alonso's theory of land use.

  1. Let It Go: Lingering Negative Affect in Response to Daily Stressors Is Associated With Physical Health Years Later.

    Science.gov (United States)

    Leger, Kate A; Charles, Susan T; Almeida, David M

    2018-03-01

    The way we respond to life's daily stressors has strong implications for our physical health. Researchers have documented the detrimental effects of initial emotional reactivity to daily stressors on future physical health outcomes but have yet to examine the effects of emotions that linger after a stressor occurs. The current study investigated how negative affect that lingers the day after a minor stressor occurs is associated with health-related outcomes. Participants ( N = 1,155) in a community-based, nationwide study answered questions about daily stressors and affect across 8 consecutive days and about their physical health almost 10 years later. Multilevel models indicated that people experience heightened levels of negative affect the day after a stressor occurs. Furthermore, higher levels of lingering negative affect are associated with greater numbers of chronic conditions and worse functional limitations 10 years later. Findings suggest that affective recovery from daily stressors has unique importance for long-term physical health.

  2. Management of Local Stressors Can Improve the Resilience of Marine Canopy Algae toGlobal Stressors

    NARCIS (Netherlands)

    Strain, E.M.A.; van Belzen, J.; van Dalen, J.; Bouma, T.J.; Airoldi, L.

    2015-01-01

    Coastal systems are increasingly threatened by multiple local anthropogenic and global climatic stressors. With the difficulties in remediating global stressors, management requires alternative approaches that focus on local scales. We used manipulative experiments to test whether reducing local

  3. Predictive performance of two PK-PD models of D2 receptor occupancy of the antipsychotics risperidone and paliperidone in rats

    NARCIS (Netherlands)

    Kozielska, Magdalena; Johnson, Martin; Pilla Reddy, Venkatesh; Vermeulen, An; de Greef, Rik; Li, Cheryl; Grimwood, Sarah; Liu, Jing; Groothuis, Genoveva; Danhof, Meindert; Proost, Johannes

    2010-01-01

    Objectives: The level of dopamine D2 receptor occupancy is predictive of efficacy and safety in schizophrenia. Population PK-PD modelling has been used to link observed plasma and brain concentrations to receptor occupancy. The objective of this study was to compare the predictive performance of two

  4. Using occupancy models to investigate the prevalence of ectoparasitic vectors on hosts: an example with fleas on prairie dogs

    Science.gov (United States)

    Eads, David A.; Biggins, Dean E.; Doherty, Paul F.; Gage, Kenneth L.; Huyvaert, Kathryn P.; Long, Dustin H.; Antolin, Michael F.

    2013-01-01

    Ectoparasites are often difficult to detect in the field. We developed a method that can be used with occupancy models to estimate the prevalence of ectoparasites on hosts, and to investigate factors that influence rates of ectoparasite occupancy while accounting for imperfect detection. We describe the approach using a study of fleas (Siphonaptera) on black-tailed prairie dogs (Cynomys ludovicianus). During each primary occasion (monthly trapping events), we combed a prairie dog three consecutive times to detect fleas (15 s/combing). We used robust design occupancy modeling to evaluate hypotheses for factors that might correlate with the occurrence of fleas on prairie dogs, and factors that might influence the rate at which prairie dogs are colonized by fleas. Our combing method was highly effective; dislodged fleas fell into a tub of water and could not escape, and there was an estimated 99.3% probability of detecting a flea on an occupied host when using three combings. While overall detection was high, the probability of detection was always dogs, flea occupancy was heightened in old/natural colonies of prairie dogs, and on hosts that were in poor condition. Occupancy was initially low in plots with high densities of prairie dogs, but, as the study progressed, the rate of flea colonization increased in plots with high densities of prairie dogs in particular. Our methodology can be used to improve studies of ectoparasites, especially when the probability of detection is low. Moreover, the method can be modified to investigate the co-occurrence of ectoparasite species, and community level factors such as species richness and interspecific interactions.

  5. The relationships of working conditions, recent stressors and childhood trauma with salivary cortisol levels

    NARCIS (Netherlands)

    Holleman, M.; Vreeburg, S.A.; Dekker, J.J.M.; Penninx, B.W.J.H.

    2012-01-01

    Background: An etiological model has been suggested where stress leads to high cortisol levels and hypothalamic-pituitary-adrenal (HPA) axis dysregulation, resulting in somatic diseases and psychopathology. To evaluate this model we examined the association of different stressors (working

  6. The relationships of working conditions, recent stressors and childhood trauma with salivary cortisol levels

    NARCIS (Netherlands)

    Holleman, Michiel; Vreeburg, Sophie A.; Dekker, Jack J. M.; Penninx, Brenda W. J. H.

    Background: An etiological model has been suggested where stress leads to high cortisol levels and hypothalamic-pituitary-adrenal (HPA) axis dysregulation, resulting in somatic diseases and psychopathology. To evaluate this model we examined the association of different stressors (working

  7. Controlling intake of uranium in the workplace: Applications of biokinetic modeling and occupational monitoring data

    Energy Technology Data Exchange (ETDEWEB)

    Leggett, Richard Wayne [ORNL; Eckerman, Keith F [ORNL; McGinn, Wilson [ORNL; Meck, Dr. Robert A. [U.S. Nuclear Regulatory Commission

    2012-01-01

    This report provides methods for interpreting and applying occupational uranium monitoring data. The methods are based on current international radiation protection guidance, current information on the chemical toxicity of uranium, and best available biokinetic models for uranium. Emphasis is on air monitoring data and three types of bioassay data: the concentration of uranium in urine; the concentration of uranium in feces; and the externally measured content of uranium in the chest. Primary Reference guidance levels for prevention of chemical effects and limitation of radiation effects are selected based on a review of current scientific data and regulatory principles for setting standards. Generic investigation levels and immediate action levels are then defined in terms of these primary guidance levels. The generic investigation and immediate actions levels are stated in terms of radiation dose and concentration of uranium in the kidneys. These are not directly measurable quantities, but models can be used to relate the generic levels to the concentration of uranium in air, urine, or feces, or the total uranium activity in the chest. Default investigation and immediate action levels for uranium in air, urine, feces, and chest are recommended for situations in which there is little information on the form of uranium taken into the body. Methods are prescribed also for deriving case-specific investigation and immediate action levels for uranium in air, urine, feces, and chest when there is sufficient information on the form of uranium to narrow the range of predictions of accumulation of uranium in the main target organs for uranium: kidneys for chemical effects and lungs for radiological effects. In addition, methods for using the information herein for alternative guidance levels, different from the ones selected for this report, are described.

  8. Abiotic stressors and stress responses

    DEFF Research Database (Denmark)

    Sulmon, Cecile; Van Baaren, Joan; Cabello-Hurtado, Francisco

    2015-01-01

    Abstract Organisms are regularly subjected to abiotic stressors related to increasing anthropogenic activities, including chemicals and climatic changes that induce major stresses. Based on various key taxa involved in ecosystem functioning (photosynthetic microorganisms, plants, invertebrates), we...... review how organisms respond and adapt to chemical- and temperature-induced stresses from molecular to population level. Using field-realistic studies, our integrative analysis aims to compare i) how molecular and physiological mechanisms related to protection, repair and energy allocation can impact...... life history traits of stressed organisms, and ii) to what extent trait responses influence individual and population responses. Common response mechanisms are evident at molecular and cellular scales but become rather difficult to define at higher levels due to evolutionary distance and environmental...

  9. Teaching Practice generated stressors and coping mechanisms ...

    African Journals Online (AJOL)

    Teaching Practice generated stressors and coping mechanisms among student teachers in Zimbabwe. ... South African Journal of Education ... We sought to establish stressors and coping mechanisms for student teachers on Teaching Practice from a Christian-related university and a government-owned teachers' college ...

  10. Stressor sensor and stress management system

    NARCIS (Netherlands)

    2012-01-01

    A stressor detection system (100) comprises sensor means (101) arranged for being attached to a person for obtaining a time-varying signal representing a physical quantity relating to an environment of the person, and processing means (102) for deriving a stressor value from the obtained signal

  11. Southern Nevada ecosystem stressors [Chapter 2

    Science.gov (United States)

    Burton K. Pendleton; Jeanne C. Chambers; Mathew L. Brooks; Steven M. Ostoja

    2013-01-01

    Southern Nevada ecosystems and their associated resources are subject to a number of global and regional/local stressors that are affecting the sustainability of the region. Global stressors include elevated carbon dioxide (CO2) concentrations and associated changes in temperature and precipitation patterns and amounts, solar radiation, and nutrient cycles (Smith and...

  12. Predictive habitat models derived from nest-box occupancy for the endangered Carolina northern flying squirrel in the southern Appalachians

    Science.gov (United States)

    Ford, W. Mark; Evans, A.M.; Odom, Richard H.; Rodrigue, Jane L.; Kelly, C.A.; Abaid, Nicole; Diggins, Corinne A.; Newcomb, Doug

    2016-01-01

    In the southern Appalachians, artificial nest-boxes are used to survey for the endangered Carolina northern flying squirrel (CNFS; Glaucomys sabrinus coloratus), a disjunct subspecies associated with high elevation (>1385 m) forests. Using environmental parameters diagnostic of squirrel habitat, we created 35 a priori occupancy models in the program PRESENCE for boxes surveyed in western North Carolina, 1996-2011. Our best approximating model showed CNFS denning associated with sheltered landforms and montane conifers, primarily red spruce Picea rubens. As sheltering decreased, decreasing distance to conifers was important. Area with a high probability (>0.5) of occupancy was distributed over 18662 ha of habitat, mostly across 10 mountain ranges. Because nest-box surveys underrepresented areas >1750 m and CNFS forage in conifers, we combined areas of high occupancy with conifer GIS coverages to create an additional distribution model of likely habitat. Regionally, above 1385 m, we determined that 31795 ha could be occupied by CNFS. Known occupied patches ranged from

  13. Spatial modelling of rural infant mortality and occupation in 19th-century Britain

    Directory of Open Access Journals (Sweden)

    Paul Atkinson

    2017-04-01

    Full Text Available Background: Infant mortality in 19th century rural places has been largely neglected: to study it offers new insight into rural demography. Objective: This study examines infant mortality, and census occupations, between 1851 and 1911 across all the rural Registration Districts (RDs of England and Wales. Methods: The decadal 1850s−1900s RD-level demographic data in the GB Historical GIS (GBHGIS is analysed using latent trajectory analysis to identify clusters of RDs whose infant mortality rate (IMR trajectories are most similar: these are mapped in ArcGIS. The recently published Integrated Census Microdata (I-CeM resource is then used to study relationships between IMR and census-reported occupation. Geographically Weighted Regression is employed to explore spatial variation in the coefficient with which occupation affected IMR. Results: The study describes a previously unreported pattern of mortality variation, identifying seven groups of RDs with distinctive trajectories of infant mortality. A spatially varying link between IMR and female occupation rates in agriculture is noted. Conclusions: Spatial variation in rural social structures had demographic consequences. The decline in female agricultural occupation may have removed a source of harm to infant lives in the arable economy of the south and east, but simultaneously a source of benefit in the upland, pastoral north and west. Contribution: Findings about the costs and benefits of female agricultural employment can help explain the different trajectories of infant mortality in different regions, suggesting that female occupation and the details of what work women did could be a strong influence, positive or negative, on infant mortality.

  14. Restoring fish ecological quality in estuaries: Implication of interactive and cumulative effects among anthropogenic stressors.

    Science.gov (United States)

    Teichert, Nils; Borja, Angel; Chust, Guillem; Uriarte, Ainhize; Lepage, Mario

    2016-01-15

    Estuaries are subjected to multiple anthropogenic stressors, which have additive, antagonistic or synergistic effects. Current challenges include the use of large databases of biological monitoring surveys (e.g. the European Water Framework Directive) to help environmental managers prioritizing restoration measures. This study investigated the impact of nine stressor categories on the fish ecological status derived from 90 estuaries of the North East Atlantic countries. We used a random forest model to: 1) detect the dominant stressors and their non-linear effects; 2) evaluate the ecological benefits expected from reducing pressure from stressors; and 3) investigate the interactions among stressors. Results showed that largest restoration benefits were expected when mitigating water pollution and oxygen depletion. Non-additive effects represented half of pairwise interactions among stressors, and antagonisms were the most common. Dredged sediments, flow changes and oxygen depletion were predominantly implicated in non-additive interactions, whereas the remainder stressors often showed additive impacts. The prevalence of interactive impacts reflects a complex scenario for estuaries management; hence, we proposed a step-by-step restoration scheme focusing on the mitigation of stressors providing the maximum of restoration benefits under a multi-stress context. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Bisexual-Specific Minority Stressors, Psychological Distress, and Suicidality in Bisexual Individuals: the Mediating Role of Loneliness.

    Science.gov (United States)

    Mereish, Ethan H; Katz-Wise, Sabra L; Woulfe, Julie

    2017-08-01

    Bisexual individuals are at higher risk for poor mental health outcomes compared to heterosexual as well as lesbian and gay individuals and experience minority stressors, such as discrimination, from both heterosexual and sexual minority communities. However, there is little research examining the negative effects of bisexual-specific minority stressors on bisexual individuals' mental health as well as psychological factors that might help explain minority stressors' deleterious effects. This research examined the effects of distal minority stressors (i.e., anti-bisexual experiences from both heterosexual as well as lesbian and gay people) and proximal stressors (i.e., internalized heterosexism and sexual orientation concealment) on psychological distress and suicidality among bisexual adults (N = 503). Building on the relational framing of the minority stress model, we also tested one relational factor (i.e., loneliness) as a mediator of the associations between distal and proximal minority stressors and poor mental health (i.e., psychological distress and suicidality). Structural equation modeling analyses were used to test the mediating effects of loneliness on the associations between minority stressors and psychological distress and suicidality. Although distal and proximal minority stressors were not associated with each other, loneliness mediated the effects of distal and proximal minority stressors on psychological distress and suicidality. The results of this study underscore the importance of targeting bisexual-specific minority stressors as well as loneliness in preventive interventions to improve the mental health of bisexual individuals.

  16. Implications for environmental health of multiple stressors

    International Nuclear Information System (INIS)

    Mothersill, Carmel; Seymour, Colin

    2009-01-01

    Recent insights into the mechanisms underlying the biological effects of low dose effects of ionising radiation have revealed that similar mechanisms can be induced by chemical stressors in the environment. This means that interactions between radiation and chemicals are likely and that the outcomes following mixed exposures to radiation and chemicals may not be predictable for human health, by consideration of single agent effects. Our understanding of the biological effects of low dose exposure has undergone a major paradigm shift. We now possess technologies which can detect very subtle changes in cells due to small exposures to radiation or other pollutants. We also understand much more now about cell communication, systems biology and the need to consider effects of low dose exposure at different hierarchical levels of organisation from molecules up to and including ecosystems. Furthermore we understand, at least in part, some of the mechanisms which drive low dose effects and which perpetuate these not only in the exposed organism but also in its progeny and in certain cases, its kin. This means that previously held views about safe doses or lack of harmful effects cannot be sustained. The International Commission on Radiological Protection (ICRP) and all national radiation and environmental protection organisations have always accepted a theoretical risk and have applied the precautionary principle and the LNT (linear-non-threshold) model which basically says that there is no safe dose of radiation. Therefore even in the absence of visible effects, exposure of people to radiation is strictly limited. This review will consider the historical context and the new discoveries and will focus on evidence for emergent effects after mixed exposures to combined stressors which include ionising radiation. The implications for regulation of low dose exposures to protect human health and environmental security will be discussed.

  17. Can "good" stressors spark "bad" behaviors? The mediating role of emotions in links of challenge and hindrance stressors with citizenship and counterproductive behaviors.

    Science.gov (United States)

    Rodell, Jessica B; Judge, Timothy A

    2009-11-01

    The authors combined affective events theory (H. M. Weiss & Cropanzano, 1996) and the transactional stress model (R. S. Lazarus & Folkman, 1984) to build and test a model specifying the dynamic, emotion-based relationships among challenge and hindrance stressors and citizenship and counterproductive behaviors. The study employed an experience sampling methodology. Results showed that challenge stressors had offsetting indirect links with citizenship behaviors through attentiveness and anxiety and a positive indirect effect on counterproductive behaviors through anxiety. Hindrance stressors had a negative indirect effect on citizenship behaviors through anxiety and a positive indirect effect on counterproductive behaviors through anxiety and anger. Finally, multilevel moderating effects showed that the relationship between hindrance stressors and anger varied according to employees' levels of neuroticism.

  18. Effect of Changing Work Stressors and Coping Resources on the Risk of Type 2 Diabetes: The OHSPIW Cohort Study.

    Science.gov (United States)

    Lian, Yulong; Sun, Qing; Guan, Suzhen; Ge, Hua; Tao, Ning; Jiang, Yu; Zhang, YanXia; Ning, Li; Xiao, Jing; Liu, Jiwen

    2018-03-01

    Little is known about the relationship between changing psychosocial work conditions and type 2 diabetes. We determined whether changing work stressors and coping resources affect the risk of type 2 diabetes. In this prospective cohort (2003-2014) of 3,740 workers without diabetes (OHSPIW [Occupational Health Study of Petroleum Industry Workers]), participants completed an evaluation of work-related stress and coping resources and type 2 diabetes diagnosis at baseline and 12 years follow-up (two waves). The changes in work stressors and coping resources were measured with the Occupation Stress Inventory-Revised and the Instrument for Stress-Related Job Analysis (Version 6.0). Type 2 diabetes was diagnosed on the basis of an oral glucose tolerance test supplemented by physician report. Increased task stressors (relative risk [RR] 1.57 [95% CI 1.03-2.63]) and decreased coping resources (RR 1.68 [95% CI 1.02-2.83]) were associated with risk of type 2 diabetes. The main risk factors were increased role overload, increased role insufficiency, increased physical environment stressors, decreased self-care, and decreased rational coping. Increased coping resources also had a buffering effect on increased task stressors and type 2 diabetes. Changes in work stressors and coping resources have an influence on the risk for type 2 diabetes, highlighting the importance of preventive measures against adverse psychosocial work conditions and reduced coping resources for diabetes prevention in the workplace. © 2017 by the American Diabetes Association.

  19. Gender differences in stressors and reactions to stressors among Jordanian university students.

    Science.gov (United States)

    Hamaideh, Shaher H

    2012-01-01

    Stress among university students has been a topic of interest for researchers and teachers for many years because it affects not only their academic performance but also their physiological and psychological health. Male and female students perceive and react to stressors differently due to their differences in appraising stressful situations. The aims of this study were to examine differences in the perception of stressors and reactions to stressors between male and female Jordanian university students, and to identify the best predictors of stressors among them. Descriptive cross-sectional design was employed. The Student-Life Stress Inventory was used to measure stressors and reactions to stressors of 465 male and 485 female Jordanian university students recruited through stratified random sampling. There were statistical differences between male and female students regarding their perception and reactions to stressors. Female students reported a higher perception of stressors in frustrations, conflict, pressures and changes, as well as emotional reactions to stressors. Male students reported higher behavioural and cognitive reactions to stressors than female students. Participation in stress workshops, perception of general health, and perception of stress level in general were found to predict stressors among male students, while mother's educational level, perception of general health, and perception of stress level in general were found to predict stressors among female students. This study showed that gender differences in perception of stressors and reactions to stressors are similar to previous studies conducted all over the world. Interventions can be developed to help students better cope with stress. Conducting specific stress-training programmes for male and female students will help in reducing stress levels.

  20. Monitoring Least Bitterns (Ixobrychis exilis) in Vermont: Detection probability and occupancy modeling

    Science.gov (United States)

    Cherukuri, Aswini; Strong, Allan; Donovan, Therese M.

    2018-01-01

    Ixobrychus exillis (Least Bittern) is listed as a species of high concern in the North American Waterbird Conservation Plan and is a US Fish and Wildlife Service migratory bird species of conservation concern in the Northeast. Little is known about the population of Least Bitterns in the Northeast because of their low population density, tendency to nest in dense wetland vegetation, and secretive behavior. Urban and agricultural development is expected to encroach on and degrade suitable wetland habitat; however, we cannot predict the effects on Least Bittern populations without more accurate information on their abundance and distribution. We conducted surveys of wetlands in Vermont to assess the efficacy of a monitoring protocol and to establish baseline Least Bittern abundance and distribution data at a sample of 29 wetland sites. Surveys yielded detections of 31 individuals at 15 of 29 sites across 3 biophysical regions and at 5 sites where occupancy had not been previously reported. Probability of occupancy was positively related to wetland size and number of patches, though the relationships were not strong enough to conclude if these were true determinants of occupancy. Call—response broadcast surveys yielded 30 detections, while passive surveys yielded 13. Call—response broadcasts (P = 0.897) increased the rate of detection by 55% compared to passive surveys (P = 0.577). Our results suggest that call—response broadcast surveys are an effective means of assessing Least Bittern occupancy and may reduce bias in long-term monitoring programs.

  1. An Organizational and Task Perspective Model Aimed at Enhancing Teachers’ Professional Development and Occupational Expertise

    NARCIS (Netherlands)

    Evers, Arnoud; Van der Heijden, Béatrice; Kreijns, Karel; Gerrichhauzen, John

    2017-01-01

    Currently, many countries, including the Netherlands, are “plagued” by severe, both quantitative and qualitative, teacher shortages that are even expected to increase in the years to come. Teachers’ occupational development, therefore, has become an important issue on the research agenda of the

  2. Enhanced FAA-hybrid III numerical dummy model in Madymo for aircraft occupant safety assessment

    NARCIS (Netherlands)

    Boucher, H.; Waagmeester, C.D.

    2003-01-01

    To improve survivability and to minimize the risk of injury to occupants in helicopter crash events, a complete Cabin Safety System concept including safety features and an enhanced FAA-Hybrid III dummy were developed within the HeliSafe project. A numerical tool was also created and validated to

  3. Basic occupational health services (BOHS) in community primary care: the MSF (Dhaka) model.

    Science.gov (United States)

    Muralidhar, Venkiteswaran; Ahasan, Md Faizul; Khan, Ahad Mahmud; Alam, Mohammad Shariful

    2017-03-20

    The Médecins Sans Frontiérs (MSF) established basic occupational health services to diagnose and treat work-related diseases among tannery, metal, plastics and garment workers and families in one of the more polluted areas of the world populated by 600 000 people. In spite of project limitations, an analysis of the 6-month data showed that of the original cohort of 5000, 3200 (64%) came for at least 1 consultation. Among them, 468 (14.6%) were diagnosed with suspected work-related diseases as per defined protocols. Follow-up consultation was performed for 1447 cases of occupational diseases and work-related injuries. The MSF experience begs the need for replication of such services in densely populated urban areas in developing nations like Bangladesh and India, where no specialty occupational health clinics exist in primary care but are desperately needed and where occupational health clinics on factory premises are exclusive to industry workers and are not accessible to communities. 2017 BMJ Publishing Group Ltd.

  4. Evaluating Amphibian Declines with Site Revisits and Occupancy Models: Status of Montane Anurans in the Pacific Northwest USA

    Directory of Open Access Journals (Sweden)

    Brome McCreary

    2009-12-01

    Full Text Available Amphibian declines have been reported in mountainous areas around the western USA. Few data quantify the extent of population losses in the Pacific Northwest, a region in which amphibian declines have received much attention. From 2001–2004, we resurveyed historical breeding sites of two species of conservation concern, the Western Toad (Bufo [=Anaxyrus] boreas and Cascades Frog (Rana cascadae. We detected B. boreas breeding at 75.9% and R. cascadae breeding at 66.6% of historical sites. When we analyzed the data using occupancy models that accounted for detection probability, we estimated the current use of historically occupied sites in our study area was 84.9% (SE = 4.9 for B. boreas and 72.4% (SE = 6.6 for R. cascadae. Our ability to detect B. boreas at sites where they were present was lower in the first year of surveys (a low snowpack year and higher at sites with introduced fish. Our ability to detect R. cascadae was lower at sites with fish. The probability that B. boreas still uses a historical site for breeding was related to the easting of the site (+ and the age of record (-. None of the variables we analyzed was strongly related to R. cascadae occupancy. Both species had increased odds of occupancy with higher latitude, but model support for this variable was modest. Our analysis suggests that while local losses are possible, these two amphibians have not experienced recent, broad population losses in the Oregon Cascades. Historical site revisitation studies such as ours cannot distinguish between population losses and site switching, and do not account for colonization of new habitats, so our analysis may overestimate declines in occupancy within our study area.

  5. Suicide Mortality Across Broad Occupational Groups in Greece: A Descriptive Study

    Directory of Open Access Journals (Sweden)

    Evangelos C. Alexopoulos

    2016-03-01

    Conclusion: Further research is needed into the work-related stressors of occupations with high suicide mortality risk and focused suicide prevention strategies should be applied within vulnerable working age populations.

  6. The impact of automation on pharmacy staff experience of workplace stressors.

    Science.gov (United States)

    James, K Lynette; Barlow, Dave; Bithell, Anne; Hiom, Sarah; Lord, Sue; Oakley, Pat; Pollard, Mike; Roberts, Dave; Way, Cheryl; Whittlesea, Cate

    2013-04-01

    Determine the effect of installing an original pack automated dispensing system (ADS) on staff experience of occupational stressors. Pharmacy staff in a National Health Service hospital in Wales, UK, were administered an anonymous occupational stressor questionnaire pre- (n = 45) and post-automation (n = 32). Survey responses pre- and post-automation were compared using Mann-Whitney U test. Statistical significance was P ≤ 0.05. Four focus groups were conducted (two groups of accredited checking technicians (ACTs) (group 1: n = 4; group 2: n = 6), one group of pharmacists (n = 17), and one group of technicians (n = 4) post-automation to explore staff experiences of occupational stressors. Focus group transcripts were analysed according to framework analysis. Survey response rate pre-automation was 78% (n = 35) and 49% (n = 16) post-automation. Automation had a positive impact on staff experience of stress (P = 0.023), illogical workload allocation (P = 0.004) and work-life balance (P = 0.05). All focus-group participants reported that automation had created a spacious working environment. Pharmacists and ACTs reported that automation had enabled the expansion of their roles. Technicians felt like 'production-line workers.' Robot malfunction was a source of stress. The findings suggest that automation had a positive impact on staff experience of stressors, improving working conditions and workload. Technicians reported that ADS devalued their skills. When installing ADS, pharmacy managers must consider the impact of automation on staff. Strategies to reduce stressors associated with automation include rotating staff activities and role expansions. © 2012 The Authors. IJPP © 2012 Royal Pharmaceutical Society.

  7. Expanding the occupational health methodology: A concatenated artificial neural network approach to model the burnout process in Chinese nurses.

    Science.gov (United States)

    Ladstätter, Felix; Garrosa, Eva; Moreno-Jiménez, Bernardo; Ponsoda, Vicente; Reales Aviles, José Manuel; Dai, Junming

    2016-01-01

    Artificial neural networks are sophisticated modelling and prediction tools capable of extracting complex, non-linear relationships between predictor (input) and predicted (output) variables. This study explores this capacity by modelling non-linearities in the hardiness-modulated burnout process with a neural network. Specifically, two multi-layer feed-forward artificial neural networks are concatenated in an attempt to model the composite non-linear burnout process. Sensitivity analysis, a Monte Carlo-based global simulation technique, is then utilised to examine the first-order effects of the predictor variables on the burnout sub-dimensions and consequences. Results show that (1) this concatenated artificial neural network approach is feasible to model the burnout process, (2) sensitivity analysis is a prolific method to study the relative importance of predictor variables and (3) the relationships among variables involved in the development of burnout and its consequences are to different degrees non-linear. Many relationships among variables (e.g., stressors and strains) are not linear, yet researchers use linear methods such as Pearson correlation or linear regression to analyse these relationships. Artificial neural network analysis is an innovative method to analyse non-linear relationships and in combination with sensitivity analysis superior to linear methods.

  8. Perceived challenges of working in a fertility clinic: a qualitative analysis of work stressors and difficulties working with patients.

    Science.gov (United States)

    Boivin, Jacky; Bunting, Laura; Koert, Emily; Ieng U, Chin; Verhaak, Christianne

    2017-02-01

    'Misinformation and lack of knowledge' (27.8%, e.g. Dr Google). Finally, the topics participants would be willing to address in Workshops were 'Communicating and Counselling with Patients' (24.9%), 'Dealing with Patient-related sources' (19.6%) and 'Clinical topics' (19.6%). Three general themes emerged. First, a theme of 'time and time trade-offs' expressed the oft-mentioned need to trade-off time spent on one activity (e.g. managing patient demands) against another activity (e.g. clinical workload, administration) with stress level dependent on the efficacy of trading-off. Second, the theme of 'multifactorial causes' of challenging patient interactions that embodied the many sources of difficulties working with patients. What staff would be willing to address in workshops was indicated by the final general theme of 'a little of everything', which linked to the need for multiple workshops addressing the multifactorial nature of challenges in fertility clinics. Only about 10% of members receiving the survey participated. The work was limited to the stressful and difficult aspects of working in fertility clinics, which may give a more negative impression than if questions about the rewards and benefits had also been included. The nature of stressors and difficulties of working in a fertility clinic are consistent with models of occupational stress and patient complexity. Specialized psychologists, management consultants and other occupational experts could assist fertility teams in overcoming many of the challenges. More research is required on the effect of encountered work stressors and perceived sources of difficulties in working with patients on staff and patient outcomes. None declared. © The Author 2017. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  9. A multistudy examination of organizational stressors, emotional labor, burnout, and turnover in sport organizations.

    Science.gov (United States)

    Larner, R J; Wagstaff, C R D; Thelwell, R C; Corbett, J

    2017-12-01

    While a growing body of research has examined the types of organizational stressors encountered by individuals and their allied responses, little is known about how such individuals manage their emotional responses to these stressors or the consequences of such behaviors. This article presents novel findings from two studies examining the moderating role that emotional labor plays in the relationship between the frequency of organizational stressor experience, burnout, turnover intentions, and actual turnover in sport. In study 1, participants (n=487) completed measures of organizational stressors (OSI-SP), emotional labor (ELS), burnout (ABQ), and turnover intentions. In study 2, a 6-month longitudinal design was used to examine measures of organizational stressors (OSI-SP), emotional labor (ELS), turnover intentions, and actual turnover. Study 1 showed that surface acting moderated the relationship between the frequency of organizational stressors and burnout in sport. Further, surface acting acted as an important mechanism through which burnout mediated the relationship between the frequency of organizational stressors and turnover intentions. Study 2 showed that surface acting moderated the relationship between the organizational stressor frequency and turnover intentions-but not actual turnover-over time. These results highlight the importance of surface acting in understanding how individuals respond to organizational stressors encountered in sport, expanding our understanding of the positive and negative responses component of the meta-model of stress, emotions, and performance. These findings also highlight potentially deleterious emotion-management behaviors that practitioners might consider when aiming to support individuals encountering organizational stressors in sport. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Assessing the influence of multiple stressors on stream diatom metrics in the upper Midwest, USA

    Science.gov (United States)

    Munn, Mark D.; Waite, Ian R.; Konrad, Christopher P.

    2018-01-01

    Water resource managers face increasing challenges in identifying what physical and chemical stressors are responsible for the alteration of biological conditions in streams. The objective of this study was to assess the comparative influence of multiple stressors on benthic diatoms at 98 sites that spanned a range of stressors in an agriculturally dominated region in the upper Midwest, USA. The primary stressors of interest included: nutrients, herbicides and fungicides, sediment, and streamflow; although the influence of physical habitat was incorporated in the assessment. Boosted Regression Tree was used to examine both the sensitivity of various diatom metrics and the relative importance of the primary stressors. Percent Sensitive Taxa, percent Highly Motile Taxa, and percent High Phosphorus Taxa had the strongest response to stressors. Habitat and total phosphorous were the most common discriminators of diatom metrics, with herbicides as secondary factors. A Classification and Regression Tree (CART) model was used to examine conditional relations among stressors and indicated that fine-grain streams had a lower percentage of Sensitive Taxa than coarse-grain streams, with Sensitive Taxa decreasing further with increased water temperature (>30 °C) and triazine concentrations (>1500 ng/L). In contrast, streams dominated by coarse-grain substrate contained a higher percentage of Sensitive Taxa, with relative abundance increasing with lower water temperatures (water depth (water temperature appears to be a major limiting factor in Midwest streams; whereas both total phosphorus and percent fines showed a slight subsidy-stress response. While using benthic algae for assessing stream quality can be challenging, field-based studies can elucidate stressor effects and interactions when the response variables are appropriate, sufficient stressor resolution is achieved, and the number and type of sites represent a gradient of stressor conditions and at least a quasi

  11. Using occupancy modeling and logistic regression to assess the distribution of shrimp species in lowland streams, Costa Rica: Does regional groundwater create favorable habitat?

    Science.gov (United States)

    Snyder, Marcia; Freeman, Mary C.; Purucker, S. Thomas; Pringle, Catherine M.

    2016-01-01

    Freshwater shrimps are an important biotic component of tropical ecosystems. However, they can have a low probability of detection when abundances are low. We sampled 3 of the most common freshwater shrimp species, Macrobrachium olfersii, Macrobrachium carcinus, and Macrobrachium heterochirus, and used occupancy modeling and logistic regression models to improve our limited knowledge of distribution of these cryptic species by investigating both local- and landscape-scale effects at La Selva Biological Station in Costa Rica. Local-scale factors included substrate type and stream size, and landscape-scale factors included presence or absence of regional groundwater inputs. Capture rates for 2 of the sampled species (M. olfersii and M. carcinus) were sufficient to compare the fit of occupancy models. Occupancy models did not converge for M. heterochirus, but M. heterochirus had high enough occupancy rates that logistic regression could be used to model the relationship between occupancy rates and predictors. The best-supported models for M. olfersii and M. carcinus included conductivity, discharge, and substrate parameters. Stream size was positively correlated with occupancy rates of all 3 species. High stream conductivity, which reflects the quantity of regional groundwater input into the stream, was positively correlated with M. olfersii occupancy rates. Boulder substrates increased occupancy rate of M. carcinus and decreased the detection probability of M. olfersii. Our models suggest that shrimp distribution is driven by factors that function at local (substrate and discharge) and landscape (conductivity) scales.

  12. Occupational stress and strain in the Royal Navy 2007.

    Science.gov (United States)

    Bridger, R S; Brasher, K; Dew, A; Kilminster, S

    2008-12-01

    Previous surveys of psychological strain in the Naval Service (NS) have shown higher than expected levels of strain when compared to the general population. To repeat the survey last carried out in 2004 and to obtain further information on the nature of the occupational stressors associated with strain. General Health Questionnaire-12 strain rates and job/life stressors were measured using a Work and Well-Being Questionnaire. Models of strain were developed for male and female personnel in the Royal Navy (RN) and males in the Royal Marines (RM). The response rate was 57%. The psychological strain rate was 31.5% overall. Personnel suffering from strain tended to be 'overcommitted' to work, had low levels of commitment to the NS and had suffered stressful life events (SLEs) in the previous 12 months. Strain rates declined with age and rank in males, but not in females. Strain was significantly positively correlated with levels of overcommitment, effort-reward imbalance (ERI), role conflict, work-family conflict, organizational commitment and exposure to SLEs. Models of strain in the males and females in the RN and in the RM accounted for between 37 and 44% of the variance in strain. The survey provides evidence for both the demand control and ERI models-components of these models contribute independently to strain. High levels of commitment to the organization were associated with lower strain and exposure to SLEs to higher strain.

  13. Evaluating the efficacy of a landscape scale feral cat control program using camera traps and occupancy models.

    Science.gov (United States)

    Comer, Sarah; Speldewinde, Peter; Tiller, Cameron; Clausen, Lucy; Pinder, Jeff; Cowen, Saul; Algar, Dave

    2018-03-28

    The impact of introduced predators is a major factor limiting survivorship and recruitment of many native Australian species. In particular, the feral cat and red fox have been implicated in range reductions and population declines of many conservation dependent species across Australia, including ground-nesting birds and small to medium-sized mammals. The impact of predation by feral cats since their introduction some 200 years ago has altered the structure of native fauna communities and led to the development of landscape-scale threat abatement via baiting programs with the feral cat bait, Eradicat. Demonstrating the effectiveness of broad-scale programs is essential for managers to fine tune delivery and timing of baiting. Efficacy of feral cat baiting at the Fortescue Marsh in the Pilbara, Western Australia was tested using camera traps and occupancy models. There was a significant decrease in probability of site occupancy in baited sites in each of the five years of this study, demonstrating both the effectiveness of aerial baiting for landscape-scale removal of feral cats, and the validity of camera trap monitoring techniques for detecting changes in feral cat occupancy during a five-year baiting program.

  14. Using occupancy models to accommodate uncertainty in the interpretation of aerial photograph data: status of beaver in Central Oregon, USA

    Science.gov (United States)

    Pearl, Christopher A.; Adams, Michael J.; Haggerty, Patricia K.; Urban, Leslie

    2015-01-01

    Beavers (Castor canadensis) influence habitat for many species and pose challenges in developed landscapes. They are increasingly viewed as a cost-efficient means of riparian habitat restoration and water storage. Still, information on their status is rare, particularly in western North America. We used aerial photography to evaluate changes in beaver occupancy between 1942–1968 and 2009 in upper portions of 2 large watersheds in Oregon, USA. We used multiple observers and occupancy modeling to account for bias related to photo quality, observers, and imperfect detection of beaver impoundments. Our analysis suggested a slightly higher rate of beaver occupancy in the upper Deschutes than the upper Klamath basin. We found weak evidence for beaver increases in the west and declines in eastern parts of the study area. Our study presents a method for dealing with observer variation in photo interpretation and provides the first assessment of the extent of beaver influence in 2 basins with major water-use challenges. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

  15. Timing matters: the interval between acute stressors within chronic mild stress modifies behavioral and physiologic stress responses in male rats.

    Science.gov (United States)

    Cavigelli, Sonia A; Bao, Alexander D; Bourne, Rebecca A; Caruso, Michael J; Caulfield, Jasmine I; Chen, Mary; Smyth, Joshua M

    2018-04-12

    Chronic mild stress can lead to negative health outcomes. Frequency, duration, and intensity of acute stressors can affect health-related processes. We tested whether the temporal pattern of daily acute stressors (clustered or dispersed across the day) affects depression-related physiology. We used a rodent model to keep stressor frequency, duration, and intensity constant, and experimentally manipulated the temporal pattern of acute stressors delivered during the active phase of the day. Adult male Sprague-Dawley rats were exposed to one of three chronic mild stress groups: Clustered: stressors that occurred within 1 hour of each other (n = 21), Dispersed: stressors that were spread out across the active phase (n = 21), and Control: no stressors presented (n = 21). Acute mild stressors included noise, strobe lights, novel cage, cage tilt, wet bedding, and water immersion. Depression-related outcomes included: sucrose preference, body weight, circulating glucocorticoid (corticosterone) concentration after a novel acute stressor and during basal morning and evening times, and endotoxin-induced circulating interleukin-6 concentrations. Compared to control rats, those in the Clustered group gained less weight, consumed less sucrose, had a blunted acute corticosterone response, and an accentuated acute interleukin-6 response. Rats in the Dispersed group had an attenuated corticosterone decline during the active period and after an acute stressor compared to the Control group. During a chronic mild stress experience, the temporal distribution of daily acute stressors affected health-related physiologic processes. Regular exposure to daily stressors in rapid succession may predict more depression-related symptoms, whereas exposure to stressors dispersed throughout the day may predict diminished glucocorticoid negative feedback.

  16. Development of a numerical model for calculating exposure to toxic and nontoxic stressors in the water column and sediment from drilling discharges.

    Science.gov (United States)

    Rye, Henrik; Reed, Mark; Frost, Tone Karin; Smit, Mathijs G D; Durgut, Ismail; Johansen, Øistein; Ditlevsen, May Kristin

    2008-04-01

    Drilling discharges are complex mixtures of chemical components and particles which might lead to toxic and nontoxic stress in the environment. In order to be able to evaluate the potential environmental consequences of such discharges in the water column and in sediments, a numerical model was developed. The model includes water column stratification, ocean currents and turbulence, natural burial, bioturbation, and biodegradation of organic matter in the sediment. Accounting for these processes, the fate of the discharge is modeled for the water column, including near-field mixing and plume motion, far-field mixing, and transport. The fate of the discharge is also modeled for the sediment, including sea floor deposition, and mixing due to bioturbation. Formulas are provided for the calculation of suspended matter and chemical concentrations in the water column, and burial, change in grain size, oxygen depletion, and chemical concentrations in the sediment. The model is fully 3-dimensional and time dependent. It uses a Lagrangian approach for the water column based on moving particles that represent the properties of the release and an Eulerian approach for the sediment based on calculation of the properties of matter in a grid. The model will be used to calculate the environmental risk, both in the water column and in sediments, from drilling discharges. It can serve as a tool to define risk mitigating measures, and as such it provides guidance towards the "zero harm" goal.

  17. Shared effects of organic microcontaminants and environmental stressors on biofilms and invertebrates in impaired rivers

    International Nuclear Information System (INIS)

    Sabater, S.; Barceló, D.; De Castro-Català, N.; Ginebreda, A.; Kuzmanovic, M.; Petrovic, M.; Picó, Y.; Ponsatí, L.; Tornés, E.; Muñoz, I.

    2016-01-01

    Land use type, physical and chemical stressors, and organic microcontaminants were investigated for their effects on the biological communities (biofilms and invertebrates) in several Mediterranean rivers. The diversity of invertebrates, and the scores of the first principal component of a PCA performed with the diatom communities were the best descriptors of the distribution patterns of the biological communities against the river stressors. These two metrics decreased according to the progressive site impairment (associated to higher area of agricultural and urban-industrial, high water conductivity, higher dissolved organic carbon and dissolved inorganic nitrogen concentrations, and higher concentration of organic microcontaminants, particularly pharmaceutical and industrial compounds). The variance partition analyses (RDAs) attributed the major share (10%) of the biological communities' response to the environmental stressors (nutrients, altered discharge, dissolved organic matter), followed by the land use occupation (6%) and of the organic microcontaminants (2%). However, the variance shared by the three groups of descriptors was very high (41%), indicating that their simultaneous occurrence determined most of the variation in the biological communities. - Highlights: • River impairment was associated to increasing agricultural and urban-industrial areas, and sites were having waters with high water conductivity and nutrient concentrations, and higher concentrations of organic microcontaminants, particularly pharmaceutical and alkylphenol compounds. • Physico-chemical stressors (high nutrients and dissolved organic matter, altered water flow) were the ones mostly affecting biodiversity. • The simultaneous occurrence of microcontaminants with physico-chemical stressors in urban-industrial areas produced a much higher effect than the simple addition of stressors. - Organic microcontaminants reinforce the effects of environmental and land use stressors on

  18. High level of work stressors increase the risk of mental-emotional disturbances among airline pilots

    Directory of Open Access Journals (Sweden)

    Indah S. Widyahening

    2007-06-01

    Full Text Available Civilian airline pilots have one of the most stressful occupations. The aim of this study was to identify the effect of work stressors and other factors on mental-emotional disturbances among airline pilots. A cross-sectional study was done by interviewing selected pilots of an airline using appropriate questionnaires, during their routine medical examination from May to July 1999 in Jakarta. Five aspects of work stressor were assessed: working conditions, physical conditions of working environment, career development, organization and interpersonal relationship. Mental-emotional disturbances were determined by using the Symptom Checklist 90 (SCL 90 questionnaire. Data analysis was carried out using relative risk by Cox regression with constant time. From 128 subjects interviewed, 109 could be analyzed. Most of the subjects were married (73.4% and college graduates (91.7%. The number of captains and first officers were almost equal. The prevalence of mental-emotional disturbances was 39.4%. Mental-emotional disturbances were significantly related to work stressors and moderately related to household tension (P = 0.184. Compared to pilots with low levels of work stressors, those with high or very high levels of work stressors had a risk of 4.6 times of mental-emotional disturbances [adjusted relative risk (RRa = 4.64; 95% confidence interval (CI = 1.01 – 19.65]. Adequate guides to cope work stressors and household tension which related to mental-emotional disturbance is recommended. (Med J Indones 2007; 16:117-21Keywords: mental-emotional disturbance, work stressors, household tension, airline pilots

  19. Landscape-scale evaluation of asymmetric interactions between Brown Trout and Brook Trout using two-species occupancy models

    Science.gov (United States)

    Wagner, Tyler; Jefferson T. Deweber,; Jason Detar,; John A. Sweka,

    2013-01-01

    Predicting the distribution of native stream fishes is fundamental to the management and conservation of many species. Modeling species distributions often consists of quantifying relationships between species occurrence and abundance data at known locations with environmental data at those locations. However, it is well documented that native stream fish distributions can be altered as a result of asymmetric interactions between dominant exotic and subordinate native species. For example, the naturalized exotic Brown Trout Salmo trutta has been identified as a threat to native Brook Trout Salvelinus fontinalis in the eastern United States. To evaluate large-scale patterns of co-occurrence and to quantify the potential effects of Brown Trout presence on Brook Trout occupancy, we used data from 624 stream sites to fit two-species occupancy models. These models assumed that asymmetric interactions occurred between the two species. In addition, we examined natural and anthropogenic landscape characteristics we hypothesized would be important predictors of occurrence of both species. Estimated occupancy for Brook Trout, from a co-occurrence model with no landscape covariates, at sites with Brown Trout present was substantially lower than sites where Brown Trout were absent. We also observed opposing patterns for Brook and Brown Trout occurrence in relation to percentage forest, impervious surface, and agriculture within the network catchment. Our results are consistent with other studies and suggest that alterations to the landscape, and specifically the transition from a forested catchment to one that contains impervious surface or agriculture, reduces the occurrence probability of wild Brook Trout. Our results, however, also suggest that the presence of Brown Trout results in lower occurrence probability of Brook Trout over a range of anthropogenic landscape characteristics, compared with streams where Brown Trout were absent.

  20. An assessment of anthropogenic and climatic stressors on estuaries using a spatio-temporal GIS-modelling approach for sustainability: Towamba estuary, southeastern Australia.

    Science.gov (United States)

    Al-Nasrawi, Ali K M; Hamylton, Sarah M; Jones, Brian G

    2018-06-03

    Monitoring estuarine ecological-geomorphological dynamics has become a crucial aspect of studying the impacts of climate change and worldwide infrastructure development in coastal zones. Together, these factors have changed the natural eco-geomorphic processes that affect estuarine regimes and comprehensive modelling of coastal resources can assist managers to make appropriate decisions about their sustainable use. This study has utilised Towamba estuary (southeastern NSW, Australia), to demonstrate the value and priority of modelling estuarine dynamism as a measure of the rates and consequences of eco-geomorphic changes. This research employs several geoinformatic modelling approaches over time to investigate and assess how climate change and human activities have altered this estuarine eco-geomorphic setting. Multitemporal trend/change analysis of sediment delivery, shoreline positions and land cover, determined from fieldwork and GIS analysis of remote sensing datasets, shows significant spatio-temporal changes to the elevation and areal extent of sedimentary facies in the Towamba estuary over the past 65 years. Geomorphic growth (~ 2600 m 2 annually) has stabilised the estuarine habitats, particularly within native vegetation, salt marsh and mangrove areas. Geomorphic changes have occurred because of a combination of sediment runoff from the mostly unmodified terrestrial catchment, nearshore processes (ocean dynamics) and human activities. The construction of GIS models, verified with water and sediment samples, can characterise physical processes and quantify changes within the estuarine ecosystem. Such robust models will allow resource managers to evaluate the potential effects of changes to the current coastal ecosystems.

  1. Inference for occupancy and occupancy dynamics

    Science.gov (United States)

    O'Connell, Allan F.; Bailey, Larissa L.; O'Connell, Allan F.; Nichols, James D.; Karanth, K. Ullas

    2011-01-01

    This chapter deals with the estimation of occupancy as a state variable to assess the status of, and track changes in, species distributions when sampling with camera traps. Much of the recent interest in occupancy estimation and modeling originated from the models developed by MacKenzie et al. (2002, 2003), although similar methods were developed independently (Azuma et al. 1990; Bayley and Petersen 2001; Nichols and Karanth, 2002; Tyre et al. 2003), all of which deal with species occurrence information and imperfect detection. Less than a decade after these publications, the modeling and estimation of species occurrence and occupancy dynamics have increased significantly. Special features of scientific journals have explored innovative uses of detection–nondetection data with occupancy models (Vojta 2005), and an entire volume has synthesized the use and application of occupancy estimation methods (MacKenzie et al. 2006). Reviews of the topical concepts, philosophical considerations, and various sampling designs that can be used for occupancy estimation are now readily available for a range of audiences (MacKenzie and Royle 2005; MacKenzie et al. 2006; Bailey et al. 2007; Royle and Dorazio 2008; Conroy and Carroll 2009; Kendall and White 2009; Hines et al. 2010; Link and Barker 2010). As a result, it would be pointless here to recast all that these publications have so eloquently articulated, but that said, a review of any scientific topic requires sufficient context and relevant background information, especially when relatively new methodologies and techniques such as occupancy estimation and camera traps are involved. This is especially critical in a digital age where new information is published at warp speed, making it increasingly difficult to stay abreast of theoretical advances and research developments.

  2. Community occupancy before-after-control-impact (CO-BACI) analysis of Hurricane Gudrun on Swedish forest birds.

    Science.gov (United States)

    Russell, James C; Stjernman, Martin; Lindström, Åke; Smith, Henrik G

    2015-04-01

    Resilience of ecological communities to perturbation is important in the face of increased global change from anthropogenic stressors. Monitoring is required to detect the impact of, and recovery from, perturbations, and before-after-control-impact (BACI) analysis provides a powerful framework in this regard. However, species in a community are not observed with perfect detection, and occupancy analysis is required to correct for imperfect detectability of species. We present a Bayesian community occupancy before-after-control-impact (CO-BACI) framework to monitor ecological community response to perturbation when constituent species are imperfectly detected. We test the power of the model to detect changes in community composition following an acute perturbation with simulation. We then apply the model to a study of the impact of a large hurricane on the forest bird community of Sweden, using data from the national bird survey scheme. Although simulation shows the model can detect changes in community occupancy following an acute perturbation, application to a Swedish forest bird community following a major hurricane detected no change in community occupancy despite widespread forest loss. Birds with landscape occupancy less than 50% required correcting for detectability. We conclude that CO-BACI analysis is a useful tool that can incorporate rare species in analyses and detect occupancy changes in ecological communities following perturbation, but, because it does not include abundance, some impacts may be overlooked.

  3. The role of door orientation on occupant injury in a nearside impact: a CIREN, MADYMO modeling and experimental study.

    Science.gov (United States)

    Tencer, Allan F; Kaufman, Robert; Huber, Philippe; Mock, Charles

    2005-12-01

    This study addressed the effects of vehicle height mismatch in side impact crashes. A light truck or SUV tends to strike the door of a passenger car higher causing the upper border to lead into the occupant space. Conversely, an impact centered lower on the door, from a passenger car, causes the lower border to lead. We proposed the hypothesis that the type of injury sustained by the occupant could be related to door orientation during its intrusion into the passenger compartment. Data on door orientation and nearside occupant injuries were collected from 125 side impact crashes reported in the CIREN database. Experimental testing was performed using a pendulum carrying a frame and a vehicle door, impacting against a USDOT SID. The frame allowed the door orientation to be changed. A model was developed in MADYMO (v 6.2) using the more biofidelic dummies, BIOSID, and SIDIIs as well as USDOT SID. In side impact crashes with the lower border of the door leading, 81% of occupants sustained pelvic injury, 42% suffered rib fractures, and the rate of organ injury was 0.84. With the upper border leading, 46% of occupants sustained pelvic injury, 71% sustained rib fracture, and the rate of organ injuries per case increased to 1.13. The differences in the groups with respect to pelvic injury were significant at p = 0.01, rib fracture, p = 0.10, and organ injury, p = 0.001. Experimental testing showed that when the door angle changed from lower to upper border leading, peak T4 acceleration increased by 273% and pelvic acceleration decreased by 44%. The model demonstrated that when the door angle changed from lower to upper border leading, the USDOT SID showed a 29% increase in T4 acceleration and a 57% decrease in pelvic acceleration. The BIOSID dummy demonstrated a 36% increase in T1 acceleration, a 44% increase in abdominal rib 1 deflection, a 91% increase in thoracic rib 1 deflection, and a 33% decrease in pelvic acceleration. These data add more insight to the problem of

  4. Common Mental Disorders among Occupational Groups: Contributions of the Latent Class Model

    Directory of Open Access Journals (Sweden)

    Kionna Oliveira Bernardes Santos

    2016-01-01

    Full Text Available Background. The Self-Reporting Questionnaire (SRQ-20 is widely used for evaluating common mental disorders. However, few studies have evaluated the SRQ-20 measurements performance in occupational groups. This study aimed to describe manifestation patterns of common mental disorders symptoms among workers populations, by using latent class analysis. Methods. Data derived from 9,959 Brazilian workers, obtained from four cross-sectional studies that used similar methodology, among groups of informal workers, teachers, healthcare workers, and urban workers. Common mental disorders were measured by using SRQ-20. Latent class analysis was performed on each database separately. Results. Three classes of symptoms were confirmed in the occupational categories investigated. In all studies, class I met better criteria for suspicion of common mental disorders. Class II discriminated workers with intermediate probability of answers to the items belonging to anxiety, sadness, and energy decrease that configure common mental disorders. Class III was composed of subgroups of workers with low probability to respond positively to questions for screening common mental disorders. Conclusions. Three patterns of symptoms of common mental disorders were identified in the occupational groups investigated, ranging from distinctive features to low probabilities of occurrence. The SRQ-20 measurements showed stability in capturing nonpsychotic symptoms.

  5. Development of a numerical model for calculating exposure to toxic and nontoxic stressors in the water column and sediment from drilling discharges

    NARCIS (Netherlands)

    Rye, H.; Reed, M.; Frost, T.K.; Smit, M.G.D.; Durgut, S.

    2008-01-01

    Drilling discharges are complex mixtures of chemical components and particles which might lead to toxic and nontoxic stress in the environment. In order to be able to evaluate the potential environmental consequences of such discharges in the water column and in sediments, a numerical model was

  6. Psychosocial stressors at work and musculoskeletal problems

    NARCIS (Netherlands)

    Houtman, I.L.D.; Bongers, P.M.; Smulders, P.G.W.; Kompier, M.A.J.

    1994-01-01

    Objectives - This paper examines the relationship between work stressors and the following health indicators: psychosomatic complaints, health behavior, and musculoskeletal problems. Methods - Secondary analyses were performed on data from the National Work and Living Condition Survey, which

  7. Direct and indirect effects of multiple stressors on stream invertebrates across watershed, reach and site scales: A structural equation modelling better informing on hydromorphological impacts.

    Science.gov (United States)

    Villeneuve, B; Piffady, J; Valette, L; Souchon, Y; Usseglio-Polatera, P

    2018-01-15

    The purpose of our approach was to take into account the nested spatial scales driving stream functioning in the description of pressures/ecological status links by analysing the results of a hierarchical model. The development of this model has allowed us to answer the following questions: Does the consideration of the indirect links between anthropogenic pressures and stream ecological status modify the hierarchy of pressure types impacting benthic invertebrates? Do the different nested scales play different roles in the anthropogenic pressures/ecological status relationship? Does this model lead to better understanding of the specific role of hydromorphology in the evaluation of stream ecological status? To achieve that goal, we used the Partial Least Square (PLS) path modelling method to develop a structural model linking variables describing (i) land use and hydromorphological alterations at the watershed scale, (ii) hydromorphological alterations at the reach scale, (iii) nutrients-organic matter contamination levels at the site scale, and (iv) substrate characteristics at the sampling site scale, to explain variation in values of a macroinvertebrate-based multimetric index: the French I 2 M 2 . We have highlighted the importance of land use effects exerted on both hydromorphological and chemical characteristics of streams observed at finer scales and their subsequent indirect impact on stream ecological status. Hydromorphological alterations have an effect on the substrate mosaic structure and on the concentrations of nutrients and organic matter at site scale. This result implies that stream hydromorphology can have a major indirect effect on macroinvertebrate assemblages and that the hierarchy of impacts of anthropogenic pressures on stream ecological status generally described in the literature - often determining strategic restoration priorities - has to be re-examined. Finally, the effects of nutrients and organic matter on macroinvertebrate assemblages

  8. Occupational rhinitis.

    Science.gov (United States)

    Petrick, Maria M; Slavin, Raymond G

    2003-05-01

    This article aims to define occupational rhinitis, classify its various causes, review the steps in its diagnosis, and describe its nonpharmacologic and pharmacologic principles of management. Occupational rhinitis frequently coexists with asthma but also occurs alone. Although it does not have the same impact as occupational asthma, occupational rhinitis causes distress, discomfort, and work inefficiency. By concentrating on the patient's workplace, the clinician has an opportunity to practice preventive medicine: to recognize substances in the patient's micro- and macroenvironment that are causing the problems and then to intervene by altering the environment or removing the patient from the environment.

  9. A model teacher education program in health occupations at the University of Illinois, Urbana-Champaign, Illinois, USA.

    Science.gov (United States)

    Vittetoe, M C

    1977-01-01

    The Health Occupations Teacher Education Program at the University of Illinois, Urbana-Champaign, U.S.A. has been shown to be a viable and productive model for the preparation of health occupations teacher for both traditional and non-traditional educational settings. Since 1971 the undergraduate program has grown from twelve students to 30 students on-campus, with more than two hundred students in the extramural and part-time programs. Recruitment has been accomplished through professional association meetings, journals and personal contacts. More recently, persons have heard of the program through extramural classes and from students, graduates or University personnel who have become familiar with the program. Program development has been effected through the "capstone" concept, which allows for transfer of technical credit in one's specialty, capped by teacher education courses and concentrated courses to enhance one's expertise in the teaching role. Courses developed by the HOTEP faculty are based on perceived student needs, and were designed as both integrative and collaborative courses to be taken with other health care practitioners and teachers. Evaluation procedures have shown the health occupations teacher education program to be effective in preparing graduates for their predicted roles. The numbers of new students, kinds of health practitioners, and numbers of graduates have increased steadily. Implementation of courses into the Health Occupations Teacher Education Program curriculum has been gradual, so that the undergraduate core of courses is now considered to be nearly complete. Much curriculum planning has already been completed on the master's program, from which some students have already graduated. A doctoral program is also open to those ready for this level of preparation. More time and effort needs to be and will be expended on courses for the master's and doctoral level programs being developed. This health occupations teacher education has

  10. Development and validation of a prediction model for long-term sickness absence based on occupational health survey variables.

    Science.gov (United States)

    Roelen, Corné; Thorsen, Sannie; Heymans, Martijn; Twisk, Jos; Bültmann, Ute; Bjørner, Jakob

    2018-01-01

    The purpose of this study is to develop and validate a prediction model for identifying employees at increased risk of long-term sickness absence (LTSA), by using variables commonly measured in occupational health surveys. Based on the literature, 15 predictor variables were retrieved from the DAnish National working Environment Survey (DANES) and included in a model predicting incident LTSA (≥4 consecutive weeks) during 1-year follow-up in a sample of 4000 DANES participants. The 15-predictor model was reduced by backward stepwise statistical techniques and then validated in a sample of 2524 DANES participants, not included in the development sample. Identification of employees at increased LTSA risk was investigated by receiver operating characteristic (ROC) analysis; the area-under-the-ROC-curve (AUC) reflected discrimination between employees with and without LTSA during follow-up. The 15-predictor model was reduced to a 9-predictor model including age, gender, education, self-rated health, mental health, prior LTSA, work ability, emotional job demands, and recognition by the management. Discrimination by the 9-predictor model was significant (AUC = 0.68; 95% CI 0.61-0.76), but not practically useful. A prediction model based on occupational health survey variables identified employees with an increased LTSA risk, but should be further developed into a practically useful tool to predict the risk of LTSA in the general working population. Implications for rehabilitation Long-term sickness absence risk predictions would enable healthcare providers to refer high-risk employees to rehabilitation programs aimed at preventing or reducing work disability. A prediction model based on health survey variables discriminates between employees at high and low risk of long-term sickness absence, but discrimination was not practically useful. Health survey variables provide insufficient information to determine long-term sickness absence risk profiles. There is a need for

  11. Early post-stressor intervention with minocycline, a second-generation tetracycline, attenuates post-traumatic stress response in an animal model of PTSD.

    Science.gov (United States)

    Levkovitz, Yechiel; Fenchel, Daphna; Kaplan, Zeev; Zohar, Joseph; Cohen, Hagit

    2015-01-01

    We assessed the effects of minocycline, a tetracycline with anti-inflammatory, anti-apoptotic and neuroprotective capacities, in an animal model of post-traumatic stress disorder (PTSD). Rats were exposed to psychogenic stress and treated 1h later with minocycline or saline. Behavioral measures included the elevated plus-maze (EPM) and acoustic startle response (ASR) 7 days post stress-exposure. One day after behavioral testing, animals were exposed to a trauma cue and freezing response was assessed. Local levels of cytokines interleukin-1 (IL-1), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in the hippocampus, frontal cortex (FC) and hypothalamus were then examined. Minocycline attenuated anxious-like behaviors in stress-exposed rats. In addition, decreased levels of cytokines were measured in exposed rats treated with minocycline compared to their counterparts treated with saline. This study suggests a potential use of minocycline in preventing physiological and behavioral alternations resulting from acute exposure to psychological stress. As this is the first study to report beneficial outcomes for minocycline treatment in an animal model of PTSD, further investigations of the use of minocycline in stress-related conditions with emphasis on PTSD is needed. Copyright © 2014 Elsevier B.V. and ECNP. All rights reserved.

  12. Intra-family stressors among adult siblings sharing caregiving for parents.

    Science.gov (United States)

    Ngangana, Pamela C; Davis, Bertha L; Burns, Dorothy P; McGee, Zina T; Montgomery, Arlene J

    2016-12-01

    The aim of this study was to describe a Neuman Systems Model-guided study of perceptions of family stressors experienced by adult siblings who share caregiving for their parents and the influence of these stressors on adult siblings' relationships. The task of providing informal care for disabled parents is often shared by adult siblings. Family stressors experienced as part of caregiving may affect the sibling relationship. A mixed-method study design was used. Data were collected during 2013-2014 from 84 adult sibling caregivers. Seventy-two caregivers provided quantitative data for the Lifespan Sibling Relationship Scale and the Zarit Burden Scale and 79 provided qualitative data for the open-ended question. Adult siblings experienced mild-to-moderate levels of burden from family stressors when they share parental caregiving. The amount of burden from intra-family stressors was negatively related to the adult sibling relationship. Beneficial and noxious stressors were evident in the participants' responses to an open-ended question. The health of the parents affected the lives of adult siblings in both negative and positive ways. Although the majority of the adult siblings expressed a willingness to care for their parent(s) in an attempt to reciprocate the care, they had received from them, challenges emerged from dealing with family stressors. © 2016 John Wiley & Sons Ltd.

  13. The Effects of Daily Co-Occurrence of Affect on Older Adults’ Reactivity to Health Stressors

    Science.gov (United States)

    Ramsey, Jennifer L.; Neupert, Shevaun D.; Mroczek, Daniel K.; Spiro, Avron

    2015-01-01

    Objectives The present study examined age differences among older adults in the daily co-occurrence of affect and its potential role in buffering the negative effects of health stressors. Design Participants were from the Veterans Affairs Normative Aging Study (NAS) and included 249 young-old adults (age = 60–79 years, M=71.6) and 64 old-old adults (age = 80–89, M = 82.9) who completed questionnaires assessing stressors, physical health symptoms, and positive and negative affect on eight consecutive days. Results An independent samples t-test showed young-old and old-old adults did not significantly differ in their mean levels of daily co-occurrence of affect. The between-person relationships among stressors, health, and daily co-occurrence of affect revealed that neither stressors nor health were significantly related to daily co-occurrence of affect. However, results from a multilevel model revealed a three-way cross-level interaction (Health Stressor X Age Group X Co-Occurrence of Affect) where old-old adults with higher levels of co-occurrence of affect were less emotionally reactive to health stressors than young-old adults. Conclusion These findings provide support for the assertion that co-occurrence of affect functions in an adaptive capacity and highlight the importance of examining domain specific stressors. PMID:26518259

  14. The effects of daily co-occurrence of affect on older adults' reactivity to health stressors.

    Science.gov (United States)

    Ramsey, Jennifer L; Neupert, Shevaun D; Mroczek, Daniel K; Spiro, Avron

    2016-01-01

    The present study examined age differences among older adults in the daily co-occurrence of affect and its potential role in buffering the negative effects of health stressors. Participants were from the Veterans Affairs Normative Aging Study and included 249 young-old adults (age = 60-79 years, M = 71.6) and 64 old-old adults (age = 80-89, M = 82.9) who completed questionnaires assessing stressors, physical health symptoms, and positive and negative affect for eight consecutive days. An independent samples t-test showed young-old and old-old adults did not significantly differ in their mean levels of daily co-occurrence of affect. The between-person relationships among stressors, health and daily co-occurrence of affect revealed that neither stressors nor health were significantly related to daily co-occurrence of affect. However, results from a multilevel model revealed a three-way cross-level interaction (health stressor × age group × co-occurrence of affect) where old-old adults with higher levels of co-occurrence of affect were less emotionally reactive to health stressors than young-old adults. These findings provide support for the assertion that co-occurrence of affect functions in an adaptive capacity and highlight the importance of examining domain-specific stressors.

  15. Psychosocial stressors in inter-human relationships and health at each life stage: A review.

    Science.gov (United States)

    Kagamimori, Sadanobu; Nasermoaddeli, Ali; Wang, Hongbing

    2004-05-01

    Currently, psychosocial stressors' impacts on health are increasing. Among these stressors, this review focused on inter-human relationships. Since social supports could be protective against ill health, consequences contributing to psychosocial stressors are discussed here in relation to social supports for each stage of childhood, adulthood and elderly status.For childhood, parental divorce/isolation, and child abuse/neglect appeared to be determinants of healthy development at either the initial or later stages. According to prospective studies, such stressors, especially those occurring until around 3 years of age, were associated with later adverse life quality in adulthood. Therefore, nationwide preventive strategies were developed in each country to monitor protective social programs.For adulthood, job strain was focused on Karasek's job strain model, effort-reward imbalance, employment grade and working hours. These psychosocial stressors were shown to affect not only the physical health but also the mental health of working people. These days, since Karoshi and even suicide related to excessive workloads are taking a toll on workplace organization, stress-coping abilities such as a sense of coherence were introduced from the individual-social interaction aspect.For elderly status, retirement, caring for the elderly, and spouse bereavement were discussed as psychosocial stressors. Some evidence indicates that these stressors could be determiants of health. Finally, social supports have been demonstrated to promote health and protect the elderly against diseases and death.

  16. Acute Stressor Effects on Goal-Directed Action in Rats

    Science.gov (United States)

    Braun, Stephanie; Hauber, Wolfgang

    2013-01-01

    Here we examined effects of acute stressors that involve either systemic coadministration of corticosterone/yohimbine (3 mg/kg each) to increase glucocorticoid/noradrenaline activity (denoted as "pharmacological" stressor) or one or several distinct restraint stressors (denoted as "single" vs. "multiple" stressor) on…

  17. An Occupational Therapy and Teaching Partnership: Applying a Scholarship of Practice Model.

    Science.gov (United States)

    Fitzgerald, Brian; MacCobb, Siobhán

    2017-07-01

    Occupational therapists must generate knowledge and evidence that relates specifically to their practice context especially when there is a paucity of literature for emerging areas of practice. This paper describes the process of adopting a scholarship of practice approach with other professionals to generate evidence for practice in mainstream post primary school settings with students with social, emotional and behavioral difficulties (SEBD). Scholarship of practice and clinical reasoning are closely intertwined as therapists generate evidence on their practice to make informed decisions and judgments. In this paper, there are a number of important concepts needing to be highlighted for their meaning in this specific context.

  18. Aggregate Exposure and Cumulative Risk Assessment--Integrating Occupational and Non-occupational Risk Factors.

    Science.gov (United States)

    Lentz, T J; Dotson, G S; Williams, P R D; Maier, A; Gadagbui, B; Pandalai, S P; Lamba, A; Hearl, F; Mumtaz, M

    2015-01-01

    Occupational exposure limits have traditionally focused on preventing morbidity and mortality arising from inhalation exposures to individual chemical stressors in the workplace. While central to occupational risk assessment, occupational exposure limits have limited application as a refined disease prevention tool because they do not account for all of the complexities of the work and non-occupational environments and are based on varying health endpoints. To be of greater utility, occupational exposure limits and other risk management tools could integrate broader consideration of risks from multiple exposure pathways and routes (aggregate risk) as well as the combined risk from exposure to both chemical and non-chemical stressors, within and beyond the workplace, including the possibility that such exposures may cause interactions or modify the toxic effects observed (cumulative risk). Although still at a rudimentary stage in many cases, a variety of methods and tools have been developed or are being used in allied risk assessment fields to incorporate such considerations in the risk assessment process. These approaches, which are collectively referred to as cumulative risk assessment, have potential to be adapted or modified for occupational scenarios and provide a tangible path forward for occupational risk assessment. Accounting for complex exposures in the workplace and the broader risks faced by the individual also requires a more complete consideration of the composite effects of occupational and non-occupational risk factors to fully assess and manage worker health problems. Barriers to integrating these different factors remain, but new and ongoing community-based and worker health-related initiatives may provide mechanisms for identifying and integrating risk from aggregate exposures and cumulative risks from all relevant sources, be they occupational or non-occupational.

  19. ICT & OTs: a model of information and communications technology acceptance and utilisation by occupational therapists (part 2).

    Science.gov (United States)

    Schaper, Louise; Pervan, Graham

    2007-01-01

    The research reported in this paper describes the development, empirical validation and analysis of a model of technology acceptance by Australian occupational therapists. The study described involved the collection of quantitative data through a national survey. The theoretical significance of this work is that it uses a thoroughly constructed research model, with one of the largest sample sizes ever tested (n=1605), to extend technology acceptance research into the health sector. Results provide strong support for the model. This work reveals the complexity of the constructs and relationships that influence technology acceptance and highlights the need to include sociotechnical and system issues in studies of technology acceptance in healthcare to improve information system implementation success in this arena. The results of this study have practical and theoretical implications for health informaticians and researchers in the field of health informatics and information systems, tertiary educators, Commonwealth and State Governments and the allied health professions.

  20. Criminal Justice Contact, Stressors, and Obesity-Related Health Problems Among Black Adults in the USA.

    Science.gov (United States)

    Archibald, Paul C; Parker, Lauren; Thorpe, Roland

    2018-04-01

    Criminal justice contact-defined as lifetime arrest, parole, or incarceration, seems to exacerbate chronic conditions, and those who are most likely to have had contact with the criminal justice system, such as Black adults, often already have pre-existing disproportionately high rates of stress and chronic conditions due to the social determinants of health that affect underrepresented minorities. Findings from this study suggest that there is a mechanism that links the stressors among Black adults manifested by such factors as family, financial, neighborhood, and personal problems with criminal justice contact to obesity-related health status. Using the National Survey of American Life (NSAL), modified Poisson regression analyses were used to determine the association between criminal justice contact, stressors, and obesity-related health problems among a national sample of Black adults (n = 5008). In the full model, the odds of experiencing obesity-related health problems for Black adults who had criminal justice contact was reduced (PR, 1.23 to 1.14) and not statistically significant. Black adults who reported experiencing family stressors (PR, 1.21; 95% CI, 1.08, 1.36), financial stressors (PR, 1.30; 95% CI, 1.16, 1.47), and personal stressors (PR, 1.16; 95% CI, 1.02, 1.31) were statistically significant and higher than those who reported not experiencing any of these stressors; neighborhood stressors was not statistically significant. The evidence suggests a relationship between the stressors associated with criminal justice contact and obesity-related health status. These findings emphasize the need to further explore the family, financial, and personal stressors for Black adults with criminal justice contact in order to further our understanding of their obesity-related health problems.ᅟ.

  1. Impact of multiple stressors on juvenile fish in estuaries of the northeast Pacific.

    Science.gov (United States)

    Toft, Jason D; Munsch, Stuart H; Cordell, Jeffery R; Siitari, Kiira; Hare, Van C; Holycross, Brett M; DeBruyckere, Lisa A; Greene, Correigh M; Hughes, Brent B

    2018-05-01

    A key step in identifying global change impacts on species and ecosystems is to quantify effects of multiple stressors. To date, the science of global change has been dominated by regional field studies, experimental manipulation, meta-analyses, conceptual models, reviews, and studies focusing on a single stressor or species over broad spatial and temporal scales. Here, we provide one of the first studies for coastal systems examining multiple stressor effects across broad scales, focused on the nursery function of 20 estuaries spanning 1,600 km of coastline, 25 years of monitoring, and seven fish and invertebrate species along the northeast Pacific coast. We hypothesized those species most estuarine dependent and negatively impacted by human activities would have lower presence and abundances in estuaries with greater anthropogenic land cover, pollution, and water flow stress. We found significant negative relationships between juveniles of two of seven species (Chinook salmon and English sole) and estuarine stressors. Chinook salmon were less likely to occur and were less abundant in estuaries with greater pollution stress. They were also less abundant in estuaries with greater flow stress, although this relationship was marginally insignificant. English sole were less abundant in estuaries with greater land cover stress. Together, we provide new empirical evidence that effects of stressors on two fish species culminate in detectable trends along the northeast Pacific coast, elevating the need for protection from pollution, land cover, and flow stressors to their habitats. Lack of response among the other five species could be related to differing resistance to specific stressors, type and precision of the stressor metrics, and limitations in catch data across estuaries and habitats. Acquiring improved measurements of impacts to species will guide future management actions, and help predict how estuarine nursery functions can be optimized given anthropogenic

  2. Are Leadership Fairness, Psychological Distress, and Role Stressors Interrelated? A Two-Wave Prospective Study of Forward and Reverse Relationships

    Directory of Open Access Journals (Sweden)

    Morten B. Nielsen

    2018-02-01

    Full Text Available While previous research has mainly considered leadership as an antecedent to psychological distress and role stressors (i.e., role ambiguity and role conflict among subordinates, a reverse relationship where these variables influence reports of leadership is also possible. To determine the directionality of the associations this two-wave prospective study assesses bidirectional relationships between fair leadership and role stressors and examines whether psychological distress mediates the reciprocal associations between fair leadership and the role stressors. Analyses were conducted in a sample of 6,790 Norwegian employees with a 2-year time-lag between measurement points. Fair leadership was associated with lower stability adjusted role ambiguity, but not role conflict, over time. Role conflict, but not role ambiguity, was related to subsequent reports of the immediate leader as less fair. Psychological distress did neither mediate the relationship between fair leadership and subsequent reports of role stressors, nor the association between role stressors and subsequent reports of fair leadership. The findings suggest that the fair leadership – role stressor association is not a one-directional process, but that exposure to role stressors also influence subordinates’ perceptions of leadership. An implication of the findings is that theoretical models of organizational leadership should include this reverse impact of role stressors. To reduce the effects of role stressors, organizations could set consistent, clear and attractive goals and provide employees with necessary information for conducting their work tasks in order to help workers understand and master their roles at the workplace.

  3. Are Leadership Fairness, Psychological Distress, and Role Stressors Interrelated? A Two-Wave Prospective Study of Forward and Reverse Relationships.

    Science.gov (United States)

    Nielsen, Morten B; Christensen, Jan O; Finne, Live B; Knardahl, Stein

    2018-01-01

    While previous research has mainly considered leadership as an antecedent to psychological distress and role stressors (i.e., role ambiguity and role conflict) among subordinates, a reverse relationship where these variables influence reports of leadership is also possible. To determine the directionality of the associations this two-wave prospective study assesses bidirectional relationships between fair leadership and role stressors and examines whether psychological distress mediates the reciprocal associations between fair leadership and the role stressors. Analyses were conducted in a sample of 6,790 Norwegian employees with a 2-year time-lag between measurement points. Fair leadership was associated with lower stability adjusted role ambiguity, but not role conflict, over time. Role conflict, but not role ambiguity, was related to subsequent reports of the immediate leader as less fair. Psychological distress did neither mediate the relationship between fair leadership and subsequent reports of role stressors, nor the association between role stressors and subsequent reports of fair leadership. The findings suggest that the fair leadership - role stressor association is not a one-directional process, but that exposure to role stressors also influence subordinates' perceptions of leadership. An implication of the findings is that theoretical models of organizational leadership should include this reverse impact of role stressors. To reduce the effects of role stressors, organizations could set consistent, clear and attractive goals and provide employees with necessary information for conducting their work tasks in order to help workers understand and master their roles at the workplace.

  4. Are Leadership Fairness, Psychological Distress, and Role Stressors Interrelated? A Two-Wave Prospective Study of Forward and Reverse Relationships

    Science.gov (United States)

    Nielsen, Morten B.; Christensen, Jan O.; Finne, Live B.; Knardahl, Stein

    2018-01-01

    While previous research has mainly considered leadership as an antecedent to psychological distress and role stressors (i.e., role ambiguity and role conflict) among subordinates, a reverse relationship where these variables influence reports of leadership is also possible. To determine the directionality of the associations this two-wave prospective study assesses bidirectional relationships between fair leadership and role stressors and examines whether psychological distress mediates the reciprocal associations between fair leadership and the role stressors. Analyses were conducted in a sample of 6,790 Norwegian employees with a 2-year time-lag between measurement points. Fair leadership was associated with lower stability adjusted role ambiguity, but not role conflict, over time. Role conflict, but not role ambiguity, was related to subsequent reports of the immediate leader as less fair. Psychological distress did neither mediate the relationship between fair leadership and subsequent reports of role stressors, nor the association between role stressors and subsequent reports of fair leadership. The findings suggest that the fair leadership – role stressor association is not a one-directional process, but that exposure to role stressors also influence subordinates’ perceptions of leadership. An implication of the findings is that theoretical models of organizational leadership should include this reverse impact of role stressors. To reduce the effects of role stressors, organizations could set consistent, clear and attractive goals and provide employees with necessary information for conducting their work tasks in order to help workers understand and master their roles at the workplace. PMID:29467702

  5. Individual and Neighborhood Stressors, Air Pollution and Cardiovascular Disease

    Science.gov (United States)

    Hazlehurst, Marnie F.; Nurius, Paula S.; Hajat, Anjum

    2018-01-01

    Psychosocial and environmental stress exposures across the life course have been shown to be relevant in the development of cardiovascular disease (CVD). Assessing more than one stressor from different domains (e.g., individual and neighborhood) and across the life course moves us towards a more integrated picture of how stress affects health and well-being. Furthermore, these individual and neighborhood psychosocial stressors act on biologic pathways, including immune function and inflammatory response, which are also impacted by ubiquitous environmental exposures such as air pollution. The objective of this study is to evaluate the interaction between psychosocial stressors, at both the individual and neighborhood level, and air pollution on CVD. This study used data from the 2009–2011 Behavioral Risk Factor Surveillance System (BRFSS) from Washington State. Adverse childhood experiences (ACEs) measured at the individual level, and neighborhood deprivation index (NDI) measured at the zip code level, were the psychosocial stressors of interest. Exposures to three air pollutants—particulate matter (both PM2.5 and PM10) and nitrogen dioxide (NO2)—were also calculated at the zip code level. Outcome measures included several self-reported CVD-related health conditions. Both multiplicative and additive interaction quantified using the relative excess risk due to interaction (RERI), were evaluated. This study included 32,151 participants in 502 unique zip codes. Multiplicative and positive additive interactions were observed between ACEs and PM10 for diabetes, in models adjusted for NDI. The prevalence of diabetes was 1.58 (95% CI: 1.40, 1.79) times higher among those with both high ACEs and high PM10 compared to those with low ACEs and low PM10 (p-value = 0.04 for interaction on the multiplicative scale). Interaction was also observed between neighborhood-level stressors (NDI) and air pollution (NO2) for the stroke and diabetes outcomes on both multiplicative and

  6. Individual and Neighborhood Stressors, Air Pollution and Cardiovascular Disease.

    Science.gov (United States)

    Hazlehurst, Marnie F; Nurius, Paula S; Hajat, Anjum

    2018-03-08

    Psychosocial and environmental stress exposures across the life course have been shown to be relevant in the development of cardiovascular disease (CVD). Assessing more than one stressor from different domains (e.g., individual and neighborhood) and across the life course moves us towards a more integrated picture of how stress affects health and well-being. Furthermore, these individual and neighborhood psychosocial stressors act on biologic pathways, including immune function and inflammatory response, which are also impacted by ubiquitous environmental exposures such as air pollution. The objective of this study is to evaluate the interaction between psychosocial stressors, at both the individual and neighborhood level, and air pollution on CVD. This study used data from the 2009-2011 Behavioral Risk Factor Surveillance System (BRFSS) from Washington State. Adverse childhood experiences (ACEs) measured at the individual level, and neighborhood deprivation index (NDI) measured at the zip code level, were the psychosocial stressors of interest. Exposures to three air pollutants-particulate matter (both PM 2.5 and PM 10 ) and nitrogen dioxide (NO₂)-were also calculated at the zip code level. Outcome measures included several self-reported CVD-related health conditions. Both multiplicative and additive interaction quantified using the relative excess risk due to interaction (RERI), were evaluated. This study included 32,151 participants in 502 unique zip codes. Multiplicative and positive additive interactions were observed between ACEs and PM 10 for diabetes, in models adjusted for NDI. The prevalence of diabetes was 1.58 (95% CI: 1.40, 1.79) times higher among those with both high ACEs and high PM 10 compared to those with low ACEs and low PM 10 ( p -value = 0.04 for interaction on the multiplicative scale). Interaction was also observed between neighborhood-level stressors (NDI) and air pollution (NO₂) for the stroke and diabetes outcomes on both

  7. Probing for Neuroadaptations to Unpredictable Stressors in Addiction: Translational Methods and Emerging Evidence

    Science.gov (United States)

    Kaye, Jesse T.; Bradford, Daniel E.; Magruder, Katherine P.; Curtin, John J.

    2017-01-01

    Stressors clearly contribute to addiction etiology and relapse in humans, but our understanding of specific mechanisms remains limited. Rodent models of addiction offer the power, flexibility, and precision necessary to delineate the causal role and specific mechanisms through which stressors influence alcohol and other drug use. This review describes a program of research using startle potentiation to unpredictable stressors that is well positioned to translate between animal models and clinical research with humans on stress neuroadaptations in addiction. This research rests on a solid foundation provided by three separate pillars of evidence from (a) rodent behavioral neuroscience on stress neuroadaptations in addiction, (b) rodent affective neuroscience on startle potentiation, and (c) human addiction and affective science with startle potentiation. Rodent stress neuroadaptation models implicate adaptations in corticotropin-releasing factor and norepinephrine circuits within the central extended amygdala following chronic alcohol and other drug use that mediate anxious behaviors and stress-induced reinstatement among drug-dependent rodents. Basic affective neuroscience indicates that these same neural mechanisms are involved in startle potentiation to unpredictable stressors in particular (vs. predictable stressors). We believe that synthesis of these evidence bases should focus us on the role of unpredictable stressors in addiction etiology and relapse. Startle potentiation in unpredictable stressor tasks is proposed to provide an attractive and flexible test bed to encourage tight translation and reverse translation between animal models and human clinical research on stress neuroadaptations. Experimental therapeutics approaches focused on unpredictable stressors hold high promise to identify, repurpose, or refine pharmacological and psychosocial interventions for addiction. PMID:28499100

  8. Probing for Neuroadaptations to Unpredictable Stressors in Addiction: Translational Methods and Emerging Evidence.

    Science.gov (United States)

    Kaye, Jesse T; Bradford, Daniel E; Magruder, Katherine P; Curtin, John J

    2017-05-01

    Stressors clearly contribute to addiction etiology and relapse in humans, but our understanding of specific mechanisms remains limited. Rodent models of addiction offer the power, flexibility, and precision necessary to delineate the causal role and specific mechanisms through which stressors influence alcohol and other drug use. This review describes a program of research using startle potentiation to unpredictable stressors that is well positioned to translate between animal models and clinical research with humans on stress neuroadaptations in addiction. This research rests on a solid foundation provided by three separate pillars of evidence from (a) rodent behavioral neuroscience on stress neuroadaptations in addiction, (b) rodent affective neuroscience on startle potentiation, and (c) human addiction and affective science with startle potentiation. Rodent stress neuroadaptation models implicate adaptations in corticotropin-releasing factor and norepinephrine circuits within the central extended amygdala following chronic alcohol and other drug use that mediate anxious behaviors and stress-induced reinstatement among drug-dependent rodents. Basic affective neuroscience indicates that these same neural mechanisms are involved in startle potentiation to unpredictable stressors in particular (vs. predictable stressors). We believe that synthesis of these evidence bases should focus us on the role of unpredictable stressors in addiction etiology and relapse. Startle potentiation in unpredictable stressor tasks is proposed to provide an attractive and flexible test bed to encourage tight translation and reverse translation between animal models and human clinical research on stress neuroadaptations. Experimental therapeutics approaches focused on unpredictable stressors hold high promise to identify, repurpose, or refine pharmacological and psychosocial interventions for addiction.

  9. Heterogeneous occupancy and density estimates of the pathogenic fungus Batrachochytrium dendrobatidis in waters of North America.

    Directory of Open Access Journals (Sweden)

    Tara Chestnut

    Full Text Available Biodiversity losses are occurring worldwide due to a combination of stressors. For example, by one estimate, 40% of amphibian species are vulnerable to extinction, and disease is one threat to amphibian populations. The emerging infectious disease chytridiomycosis, caused by the aquatic fungus Batrachochytrium dendrobatidis (Bd, is a contributor to amphibian declines worldwide. Bd research has focused on the dynamics of the pathogen in its amphibian hosts, with little emphasis on investigating the dynamics of free-living Bd. Therefore, we investigated patterns of Bd occupancy and density in amphibian habitats using occupancy models, powerful tools for estimating site occupancy and detection probability. Occupancy models have been used to investigate diseases where the focus was on pathogen occurrence in the host. We applied occupancy models to investigate free-living Bd in North American surface waters to determine Bd seasonality, relationships between Bd site occupancy and habitat attributes, and probability of detection from water samples as a function of the number of samples, sample volume, and water quality. We also report on the temporal patterns of Bd density from a 4-year case study of a Bd-positive wetland. We provide evidence that Bd occurs in the environment year-round. Bd exhibited temporal and spatial heterogeneity in density, but did not exhibit seasonality in occupancy. Bd was detected in all months, typically at less than 100 zoospores L(-1. The highest density observed was ∼3 million zoospores L(-1. We detected Bd in 47% of sites sampled, but estimated that Bd occupied 61% of sites, highlighting the importance of accounting for imperfect detection. When Bd was present, there was a 95% chance of detecting it with four samples of 600 ml of water or five samples of 60 mL. Our findings provide important baseline information to advance the study of Bd disease ecology, and advance our understanding of amphibian exposure to free

  10. Interaction of 5-HTTLPR and Idiographic Stressors Predicts Prospective Depressive Symptoms Specifically among Youth in a Multiwave Design

    Science.gov (United States)

    Hankin, Benjamin L.; Jenness, Jessica; Abela, John R. Z.; Smolen, Andrew

    2011-01-01

    5-HTTLPR, episodic stressors, depressive and anxious symptoms were assessed prospectively (child and parent report) every 3 months over 1 year (5 waves of data) among community youth ages 9 to 15 (n = 220). Lagged hierarchical linear modeling analyses showed 5-HTTLPR interacted with idiographic stressors (increases relative to the child's own…

  11. Analysis of structural relationship among the occupational dysfunction on the psychological problem in healthcare workers: a study using structural equation modeling

    Directory of Open Access Journals (Sweden)

    Mutsumi Teraoka

    2015-11-01

    Full Text Available Purpose. The purpose of this study is to demonstrate the hypothetical model based on structural relationship with the occupational dysfunction on psychological problems (stress response, burnout syndrome, and depression in healthcare workers.Method. Three cross sectional studies were conducted to assess the following relations: (1 occupational dysfunction on stress response (n = 468, (2 occupational dysfunction on burnout syndrome (n = 1,142, and (3 occupational dysfunction on depression (n = 687. Personal characteristics were collected through a questionnaire (such as age, gender, and job category, opportunities for refreshment, time spent on leisure activities, and work relationships as well as the Classification and Assessment of Occupational Dysfunction (CAOD. Furthermore, study 1 included the Stress Response Scale-18 (SRS-18, study 2 used the Japanese Burnout Scale (JBS, and study 3 employed the Center for Epidemiological Studies Depression Scale (CES-D. The Kolmogorov–Smirnov test, confirmatory factor analysis (CFA, exploratory factor analysis (EFA, and path analysis of structural equation modeling (SEM analysis were used in all of the studies. EFA and CFA were used to measure structural validity of four assessments; CAOD, SRS-18, JBS, and CES-D. For examination of a potential covariate, we assessed the correlation of the total and factor score of CAOD and personal factors in all studies. Moreover, direct and indirect effects of occupational dysfunction on stress response (Study 1, burnout syndrome (Study 2, and depression (Study 3 were also analyzed.Results. In study 1, CAOD had 16 items and 4 factors. In Study 2 and 3, CAOD had 16 items and 5 factors. SRS-18 had 18 items and 3 factors, JBS had 17 items and 3 factors, and CES-D had 20 items and 4 factors. All studies found that there were significant correlations between the CAOD total score and the personal factor that included opportunities for refreshment, time spent on leisure

  12. Identifying Stressors and Reactions to Stressors in Gifted and Non-Gifted Students

    Science.gov (United States)

    Amini, Marzieh

    2005-01-01

    Using the Student Life Stress Inventory and the Coopersmith Self-Esteem Inventory, stressors and reactions to stressors were identified in gifted high school students and compared with non-gifted students. Altogether, 340 boys and girls (156 gifted and 184 non-gifted students) from four high schools in Shiraz (two high schools for gifted and two…

  13. Alveolar macrophages have a dual role in a rat model for trimellitic anhydride-induced occupational asthma

    International Nuclear Information System (INIS)

    Valstar, Dingena L.; Schijf, Marcel A.; Nijkamp, Frans P.; Storm, Gert; Arts, Josje H.E.; Kuper, C. Frieke; Bloksma, Nanne; Henricks, Paul A.J.

    2006-01-01

    Occupational exposure to low molecular weight chemicals, like trimellitic anhydride (TMA), can result in occupational asthma. Alveolar macrophages (AMs) are among the first cells to encounter inhaled compounds. These cells can produce many different mediators that have a putative role in asthma. In this study, we examined the role of AMs in lung function and airway inflammation of rats exposed to TMA. Female Brown Norway rats were sensitized by dermal application of TMA or received vehicle alone on days 0 and 7. One day before challenge, rats received intratracheally either empty or clodronate-containing liposomes to deplete the lungs of AMs. On day 21, all rats were challenged by inhalation of TMA in air. Lung function parameters were measured before, during, within 1 h after, and 24 h after challenge. IgE levels and parameters of inflammation and tissue damage were assessed 24 h after challenge. Sensitization with TMA led to decreased lung function parameters during and within 1 h after challenge as compared to non-sensitized rats. AM depletion alleviated the TMA-induced drop in lung function parameters and induced a faster recovery compared to sham-depleted TMA-sensitized rats. It also decreased the levels of serum IgE 24 h after challenge, but did not affect the sensitization-dependent increase in lung lavage fluid IL-6 and tissue TNF-α levels. In contrast, AM depletion augmented the TMA-induced tissue damage and inflammation 24 h after challenge. AMs seem to have a dual role in this model for TMA-induced occupational asthma since they potentiate the immediate TMA-induced decrease in lung function but tended to dampen the TMA-induced inflammatory reaction 24 h later

  14. Occupational choice and values.

    OpenAIRE

    Kantas, A.

    1985-01-01

    It is suggested that psychological and sociological approaches to occupational choice can be linked together by employment of three concepts: work salience, values and motivation. Employing Vroom's (1964) cognitive model of motivation occupational choice was examined as a value attainment process. The subjects were 225 male pupils of two different school complexes in Athens, Greece. They were asked to respond to a work salience questionnaire and to rank order a set of ...

  15. Radiation protection: occupational exposure

    International Nuclear Information System (INIS)

    Shah, G.A.

    1990-01-01

    The basis of the occupational exposure limit of 50 mSv recommended by the ICRP is questioned. New dosimetry at Hiroshima and Nagasaki, the fact that the dose-response curve may be non-linear and that the relative risk model may be applicable, are some of the arguments advanced to support a reduction in the occupational exposure dose limits. 5 refs., 2 tabs., 3 figs

  16. Occupational health in Malaysia.

    Science.gov (United States)

    Rampal, Krishna Gopal; Aw, Tar-Ching; Jefferelli, Shamsul Bahrin

    2002-01-01

    This article provides a detailed examination of Malaysian occupational health agencies and their roles in formulating and enforcing standards, promoting occupational health and safety (OSH), and providing advisory services. Available OSH training is described, and the need for policies and personnel in various industries is outlined. Further, the authors discuss how international models and collaboration have influenced Malaysian OSH, and how some successes can be repeated and failures remedied.

  17. Human Stressors Are Driving Coastal Benthic Long-Lived Sessile Fan Mussel Pinna nobilis Population Structure More than Environmental Stressors.

    Directory of Open Access Journals (Sweden)

    Salud Deudero

    Full Text Available Coastal degradation and habitat disruption are severely compromising sessile marine species. The fan shell Pinna nobilis is an endemic, vulnerable species and the largest bivalve in the Mediterranean basin. In spite of species legal protection, fan shell populations are declining. Models analyzed the contributions of environmental (mean depth, wave height, maximum wave height, period of waves with high energy and mean direction of wave source versus human-derived stressors (anchoring, protection status, sewage effluents, fishing activity and diving as explanatory variables depicting Pinna nobilis populations at a mesoscale level. Human stressors were explaining most of the variability in density spatial distribution of fan shell, significantly disturbing benthic communities. Habitat protection affected P. nobilis structure and physical aggression by anchoring reveals a high impact on densities. Environmental variables instead played a secondary role, indicating that global change processes are not so relevant in coastal benthic communities as human-derived impacts.

  18. Human Stressors Are Driving Coastal Benthic Long-Lived Sessile Fan Mussel Pinna nobilis Population Structure More than Environmental Stressors.

    Science.gov (United States)

    Deudero, Salud; Vázquez-Luis, Maite; Álvarez, Elvira

    2015-01-01

    Coastal degradation and habitat disruption are severely compromising sessile marine species. The fan shell Pinna nobilis is an endemic, vulnerable species and the largest bivalve in the Mediterranean basin. In spite of species legal protection, fan shell populations are declining. Models analyzed the contributions of environmental (mean depth, wave height, maximum wave height, period of waves with high energy and mean direction of wave source) versus human-derived stressors (anchoring, protection status, sewage effluents, fishing activity and diving) as explanatory variables depicting Pinna nobilis populations at a mesoscale level. Human stressors were explaining most of the variability in density spatial distribution of fan shell, significantly disturbing benthic communities. Habitat protection affected P. nobilis structure and physical aggression by anchoring reveals a high impact on densities. Environmental variables instead played a secondary role, indicating that global change processes are not so relevant in coastal benthic communities as human-derived impacts.

  19. Occupational Stress

    OpenAIRE

    Löblová, Klára

    2011-01-01

    The thesis deals with load, stress and related questions of the working life. Work-related stress brings numerous difficulties not only to affected individuals, but as a result also to organizations. The thesis follows symptoms, impacts, somatic and mental aspects of stress, its types and also types of stressors, which cause this problem. It is concentrated on workload as a specific area of work-related stress, individual resistance to the load, factors of workload and work-related stress and...

  20. Combined exposures to workplace psychosocial stressors: relationships with mental health in a sample of NZ cleaners and clerical workers.

    Science.gov (United States)

    Lilley, R; Lamontagne, A D; Firth, H

    2011-05-01

    A combined measure of two common psychosocial stressors, called job pressure has previously been shown to be strongly associated with poor mental health in high status workers. This study tests the generalizability of this association to lower status workers. A national random sample of cleaners and clerical workers was obtained from the New Zealand (NZ) electoral roll by occupational title (n = 596). Cross-sectional data on job stressors, demographics, and mental health (GHQ-12) was collected by computer-assisted telephone interviews. Combined exposure to low job control, high job demands, and job insecurity (high job pressure) was associated with markedly elevated odds (13-fold or higher) of poor mental health after adjustment for age, sex, occupation, and education. Combined with previous findings this suggests simultaneous exposure to more than one occupational psychosocial stressor may greatly increase the risk of poor mental health among both lower and higher status workers. This report adds to the larger literature in this area, supporting the need for expanded policy and practice intervention to reduce job stressors across the working population. Copyright © 2011 Wiley-Liss, Inc.

  1. Entrepreneurial stressors as predictors of entrepreneurial burnout.

    Science.gov (United States)

    Wei, Xueyan; Cang, Shuangxin; Hisrich, Robert D

    2015-02-01

    Research on the effects of entrepreneurial stressors is limited, especially regarding its relation to the burnout that frequently occurs in the process of starting and growing a venture. The effect of the role of entrepreneurial stressors (workload, competitive comparison, demands-of-knowledge, managing responsibility, and resource requirements) on burnout (emotional exhaustion, depersonalization, and reduced personal accomplishment) was examined in a Chinese sample of entrepreneurs. Entrepreneurial stressors emerged as a significant predictor of burnout in the process of entrepreneurship in a sample of 289 entrepreneurs (63.8% men; M age = 26.2 yr.; 39.6% of their parents have been self-employed). The findings clarify the functional relationship between entrepreneurial stressors and burnout. Entrepreneurial stressors played multiple roles. Managing responsibility was an active contributor to the sense of achievement and to emotional exhaustion. Workload was an active contributor to emotional exhaustion. Demands-of-knowledge negatively affected three of the dimensions of burnout. Theoretical and practical implications for management of the effect of these relationships are discussed.

  2. The influence of flooring on environmental stressors: a study of three flooring materials in a hospital.

    Science.gov (United States)

    Harris, Debra D

    2015-01-01

    Three flooring materials, terrazzo, rubber, and carpet tile, in patient unit corridors were compared for absorption of sound, comfort, light reflectance, employee perceptions and preferences, and patient satisfaction. Environmental stressors, such as noise and ergonomic factors, effect healthcare workers and patients, contributing to increased fatigue, anxiety and stress, decreased productivity, and patient safety and satisfaction. A longitudinal comparative cohort study comparing three types of flooring assessed sound levels, healthcare worker responses, and patient Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) ratings over 42 weeks. A linear mixed model analysis was conducted to determine significant differences between the means for participant responses and objective sound meter data during all three phases of the study. A significant difference was found for sound levels between flooring type for equivalent continuous sound levels. Carpet tile performed better for sound attenuation by absorption, reducing sound levels 3.14 dBA. Preferences for flooring materials changed over the course of the study. The HCAHPS ratings aligned with the sound meter data showing that patients perceived the noise levels to be lower with carpet tiles, improving patient satisfaction ratings. Perceptions for healthcare staff and patients were aligned with the sound meter data. Carpet tile provides sound absorption that affects sound levels and influences occupant's perceptions of environmental factors that contribute to the quality of the indoor environment. Flooring that provides comfort underfoot, easy cleanability, and sound absorption influence healthcare worker job satisfaction and patient satisfaction with their patient experience. © The Author(s) 2015.

  3. Analysis of structural relationship among the occupational dysfunction on the psychological problem in healthcare workers: a study using structural equation modeling.

    Science.gov (United States)

    Teraoka, Mutsumi; Kyougoku, Makoto

    2015-01-01

    Purpose. The purpose of this study is to demonstrate the hypothetical model based on structural relationship with the occupational dysfunction on psychological problems (stress response, burnout syndrome, and depression) in healthcare workers. Method. Three cross sectional studies were conducted to assess the following relations: (1) occupational dysfunction on stress response (n = 468), (2) occupational dysfunction on burnout syndrome (n = 1,142), and (3) occupational dysfunction on depression (n = 687). Personal characteristics were collected through a questionnaire (such as age, gender, and job category, opportunities for refreshment, time spent on leisure activities, and work relationships) as well as the Classification and Assessment of Occupational Dysfunction (CAOD). Furthermore, study 1 included the Stress Response Scale-18 (SRS-18), study 2 used the Japanese Burnout Scale (JBS), and study 3 employed the Center for Epidemiological Studies Depression Scale (CES-D). The Kolmogorov-Smirnov test, confirmatory factor analysis (CFA), exploratory factor analysis (EFA), and path analysis of structural equation modeling (SEM) analysis were used in all of the studies. EFA and CFA were used to measure structural validity of four assessments; CAOD, SRS-18, JBS, and CES-D. For examination of a potential covariate, we assessed the correlation of the total and factor score of CAOD and personal factors in all studies. Moreover, direct and indirect effects of occupational dysfunction on stress response (Study 1), burnout syndrome (Study 2), and depression (Study 3) were also analyzed. Results. In study 1, CAOD had 16 items and 4 factors. In Study 2 and 3, CAOD had 16 items and 5 factors. SRS-18 had 18 items and 3 factors, JBS had 17 items and 3 factors, and CES-D had 20 items and 4 factors. All studies found that there were significant correlations between the CAOD total score and the personal factor that included opportunities for refreshment, time spent on leisure

  4. Evidence for multiple stressor interactions and effects on coral reefs.

    Science.gov (United States)

    Ban, Stephen S; Graham, Nicholas A J; Connolly, Sean R

    2014-03-01

    Concern is growing about the potential effects of interacting multiple stressors, especially as the global climate changes. We provide a comprehensive review of multiple stressor interactions in coral reef ecosystems, which are widely considered to be one of the most sensitive ecosystems to global change. First, we synthesized coral reef studies that examined interactions of two or more stressors, highlighting stressor interactions (where one stressor directly influences another) and potentially synergistic effects on response variables (where two stressors interact to produce an effect that is greater than purely additive). For stressor-stressor interactions, we found 176 studies that examined at least 2 of the 13 stressors of interest. Applying network analysis to analyze relationships between stressors, we found that pathogens were exacerbated by more costressors than any other stressor, with ca. 78% of studies reporting an enhancing effect by another stressor. Sedimentation, storms, and water temperature directly affected the largest number of other stressors. Pathogens, nutrients, and crown-of-thorns starfish were the most-influenced stressors. We found 187 studies that examined the effects of two or more stressors on a third dependent variable. The interaction of irradiance and temperature on corals has been the subject of more research (62 studies, 33% of the total) than any other combination of stressors, with many studies reporting a synergistic effect on coral symbiont photosynthetic performance (n = 19). Second, we performed a quantitative meta-analysis of existing literature on this most-studied interaction (irradiance and temperature). We found that the mean effect size of combined treatments was statistically indistinguishable from a purely additive interaction, although it should be noted that the sample size was relatively small (n = 26). Overall, although in aggregate a large body of literature examines stressor effects on coral reefs and coral

  5. Highland rural constellations. Territory occupation logics and models of order at the North of Traslasierra [Córdoba, Argentina

    Directory of Open Access Journals (Sweden)

    Fernando Diaz Terreno

    2013-07-01

    Full Text Available A set of intentioned readings made on an ancient Córdoba’s landscape reveal the occupation logics developed over centuries of territorial construction. These logics result from the combination of cultural ways of domination and exploitation of space, technical resources available and the natural landscape conditions imposed. From these processes, models of territorial order emerge as operational synthesis from the accumulation of human labor in the territory, gathering –in their own material structure– the key for future planning criteria. Just like constellation structures, order models express a form of spatial organization and some type of rurality specific from Northern Traslasierra. The aim is to arrive at a deep understanding of this postponed territory, show its cultural and natural resources and, through those, build a territorial narrative that places them back on the map of Córdoba’s regions.

  6. Relationships of role stressors with organizational citizenship behavior: a meta-analysis.

    Science.gov (United States)

    Eatough, Erin M; Chang, Chu-Hsiang; Miloslavic, Stephanie A; Johnson, Russell E

    2011-05-01

    Several quantitative reviews have documented the negative relationships that role stressors have with task performance. Surprisingly, much less attention has been directed at the impact of role stressors on other aspects of job performance, such as organizational citizenship behavior (OCB). The goal of this study was to therefore estimate the overall relationships of role stressors (i.e., role ambiguity, conflict, and overload) with OCB. A meta-analysis of 42 existing studies indicated that role ambiguity and role conflict were negatively related to OCB and that these relationships were moderated by the target of OCB, type of organization, OCB rating source, and publication status. As expected, role conflict had a stronger negative relationship with OCB than it did with task performance. Finally, we found support for a path model in which job satisfaction mediated relationships of role stressors with OCB and for a positive direct relationship between role overload and OCB.

  7. Rates and impact of trauma and current stressors among Darfuri refugees in Eastern Chad.

    Science.gov (United States)

    Rasmussen, Andrew; Nguyen, Leanh; Wilkinson, John; Vundla, Sikhumbuzo; Raghavan, Sumithra; Miller, Kenneth E; Keller, Allen S

    2010-04-01

    Darfur refugees face hardships associated with chronic displacement, including lack of basic needs and safety concerns. Psychiatric research on refugees has focused on trauma, but daily stressors may contribute more to variance in distress. This article reports rates of past trauma and current stressors among Darfur refugees and gauges the contribution of each to psychological distress and functional impairment. A representative sample of 848 Darfuris in 2 refugee camps were interviewed about traumatic events, stressors faced in the camps, psychological distress, and functional impairment. Basic needs and safety concerns were more strongly correlated with measures of distress (rs = .19-.31) than were war-related traumatic events (rs = .09-.20). Hierarchical regression supported models in which effects of trauma on distress were mediated by current stressors. Although war-related traumatic events are the initial causes of refugees' hardship, findings suggest that the day-to-day challenges and concerns in camps mediate psychological distress associated with these events.

  8. The effects of conscientiousness on the appraisals of daily stressors.

    Science.gov (United States)

    Gartland, Nicola; O'Connor, Daryl B; Lawton, Rebecca

    2012-02-01

    Conscientiousness (C) is positively associated with health and longevity although the mechanisms underlying this relationship are not fully understood. Stress may play a role in explaining the C-longevity relationship. This study investigated whether C predicted the cognitive appraisals of daily stressors/hassles. Participants (N=102) completed measures of C and cognitive appraisal in relation to the most stressful hassle they had experienced in the last 7 days. Correlational analysis revealed that Total C, Order and Industriousness were positively correlated with primary appraisals, and Responsibility was positively correlated with secondary appraisals. The facets of C were then entered into hierarchical regression models, controlling for age and gender. This demonstrated that Order (β=0.27, paccounting for 15.8% of the variance. Responsibility significantly predicted secondary appraisals (β=0.44, paccounting for 16.3% of the variance. These findings indicate that higher Order and Industriousness are related to having a greater stake in daily stressors, whereas higher Responsibility is related to greater confidence in one's ability to deal with daily stressors. These results are the first demonstration that C is related to the appraisals of daily hassles and suggest that C may moderate the experience of stress in daily life. Copyright © 2011 John Wiley & Sons, Ltd.

  9. Occupational Stress and Strain of Support Staff at a Higher Education Institution in the North West Province

    Science.gov (United States)

    Mahomed, F. E.; Naude, J. L. P.

    2006-01-01

    The aim of this study was to determine the occupational stressors and strains for support staff at a higher education institution in the North West Province, and to assess the differences between the stressors and strains of different biographical groups. A cross-sectional survey design (N = 315) was used. The ASSET and a biographical…

  10. A pilot study on the operationalization of the Model of Occupational Self Efficacy: A model for the reintegration of persons with brain injuries to their worker roles.

    Science.gov (United States)

    Soeker, Shaheed

    2015-01-01

    Traumatic brain injury causes functional limitations that can cause people to struggle to reintegrate in the workplace despite participating in work rehabilitation programmes. The aim of the study was to explore, and describe the experiences of individuals with Traumatic Brain Injury regarding returning to work through the use of the model of occupational self-efficacy. In the study 10 individuals who were diagnosed with a mild to moderate brain injury participated in the study. The research study was positioned within the qualitative paradigm specifically utilizing case study methodology. In order to gather data from the participants, individual interviews and participant observation techniques were used. Two themes emerged from the findings of the study theme one reflected the barriers related to the use of the model (i.e. Theme one: Effective participation in the model is affected by financial assistance). The second theme related to the enabling factors related to the use of the model (i.e. Theme two: A sense of normality). The findings of this study indicated that the Model of Occupational Self Efficacy (MOS) is a useful model to use in retraining the work skills of individual's who sustained a traumatic brain injury. The participants in this study could maintain employment in the open labour market for a period of at least 12 months and it improved their ability to accept their brain injury as well as adapt to their worker roles. The MOS also provides a framework for facilitating community integration.

  11. Embracing Creativity in Occupational Therapy

    Directory of Open Access Journals (Sweden)

    Lydia Royeen, MOT, OTR/L

    2015-01-01

    Full Text Available Jen Gash, an occupational therapist and creativity coach living in the UK, provided the cover art for the winter 2015 issue of The Open Journal of Occupational Therapy. The picture is titled “Over the Exe.” Jen uses her inspiration of the Kawa River model in this painting. The painting is of her husband and daughter standing where the river meets the sea. This is a metaphoric representation of rejoining the greater collective. In addition, Jen has a passion for occupational therapists to encompass creativity. A core aspect of occupational therapy is the multi-dimensional concept of occupations; it allows for occupational therapists to incorporate creativity into daily practice. Jen’s goal is for occupational therapy to embrace its creative theoretical roots.

  12. Climate Change and Interacting Stressors: Implications for ...

    Science.gov (United States)

    EPA announced the release of the final document, Climate Change and Interacting Stressors: Implications for Coral Reef Management in American Samoa. This report provides a synthesis of information on the interactive effects of climate change and other stressors on the reefs of American Samoa as well as an assessment of potential management responses. This report provides the coral reef managers of American Samoa, as well as other coral reef managers in the Pacific region, with some management options to help enhance the capacity of local coral reefs to resist the negative effects of climate change. This report was designed to take advantage of diverse research and monitoring efforts that are ongoing in American Samoa to: analyze and compile the results of multiple research projects that focus on understanding climate-related stressors and their effects on coral reef ecosystem degradation and recovery; and assess implications for coral reef managment of the combined information, including possible response options.

  13. Stressors affecting nursing students in Pakistan.

    Science.gov (United States)

    Watson, R; Rehman, S; Ali, P A

    2017-12-01

    To determine factors contributing to stress experienced by preregistration nursing students in Pakistan, using the Stressors in Nursing Students scale. The aim was to explore the psychometric properties of this instrument and to investigate the effect of a range of demographic variables on the perception of stressors in nursing students. Nursing is a stressful profession, and nursing students may experience more stress due to competing demands and challenges of nursing education, assessment, placements and worries about employment prospects. In this cross-sectional survey, data from 726 nursing students from 11 schools of nursing in Karachi, Pakistan, were collected using a questionnaire. Data were analysed using descriptive as well inferential statistics. An exploratory factor analysis was also conducted. There was no apparent factor structure to the Stressors in Nursing Students scale, unlike in previous studies. The total score on the Stressors in Nursing Students scale was related to gender with males scoring higher. The score generally increased over 4 years of the programme, and students in private schools of nursing scored higher than those in public schools of nursing. Nursing students in Pakistan do not appear to differentiate between different stressors, and this may be due to cultural differences in the students and to the structure of the programme and the articulation between the academic and clinical aspects. Likewise, cultural reasons may account for differences between stress experienced by male and female students. The fact that scores on the Stressors in Nursing Students scale increased over 4 years of the programme and males scored higher than females should alert nursing schools and policymakers related to nursing education and workforce to pay attention to prevent attrition from nursing programmes. © 2017 International Council of Nurses.

  14. Exposure to stressors and trajectories of perceived stress among older adults.

    Science.gov (United States)

    Vasunilashorn, Sarinnapha; Lynch, Scott M; Glei, Dana A; Weinstein, Maxine; Goldman, Noreen

    2015-03-01

    Models of stress incorporate both the environmental demands experienced by individuals (stressors) and the appraisal of these life events (perceptions). Because little is known about the extent to which experience and perceptions are related, we examine this relationship in a nationally representative population of older Taiwanese adults. Using growth models applied to data from 3 waves (1999, 2003, and 2007) of the Taiwan Longitudinal Study of Aging, we (a) investigate patterns of change in perceived stress in later adulthood and (b) examine how experienced stressors influence perceived stress. Participants were asked to report the presence of, and in some cases the degree of, exposure to stressors including total number of medical conditions, difficulty with activities of daily living, difficulty with mobility functions, being financially worse off compared with the prior wave, experiencing the death of a child, and experiencing a marital disruption. Items reflecting perceived stress included concerns about various domains pertaining to the respondent and his/her family member. Our results indicate that exposure to stressors increases, whereas perceived stress decreases, over time. Change in exposure to stressors is not generally associated with change in perceptions of stress, with the exception of a summary measure of health-related exposure to stressors. An increase in poor health over time is related to an increase in perceived stress in all domains. The results underscore the importance of distinguishing between perceptions of stress and exposure to stressors when studying the links between stress and health among older adults. Furthermore, the diminishing linkage between experienced stressors and perceptions of stress suggests that older adults' appraisal may be an adaptive coping strategy that emerges to buffer some of the difficulties that are inevitable in later life. © The Author 2014. Published by Oxford University Press on behalf of The

  15. Managing for interactions between local and global stressors of ecosystems.

    Science.gov (United States)

    Brown, Christopher J; Saunders, Megan I; Possingham, Hugh P; Richardson, Anthony J

    2013-01-01

    Global stressors, including climate change, are a major threat to ecosystems, but they cannot be halted by local actions. Ecosystem management is thus attempting to compensate for the impacts of global stressors by reducing local stressors, such as overfishing. This approach assumes that stressors interact additively or synergistically, whereby the combined effect of two stressors is at least the sum of their isolated effects. It is not clear, however, how management should proceed for antagonistic interactions among stressors, where multiple stressors do not have an additive or greater impact. Research to date has focussed on identifying synergisms among stressors, but antagonisms may be just as common. We examined the effectiveness of management when faced with different types of interactions in two systems--seagrass and fish communities--where the global stressor was climate change but the local stressors were different. When there were synergisms, mitigating local stressors delivered greater gains, whereas when there were antagonisms, management of local stressors was ineffective or even degraded ecosystems. These results suggest that reducing a local stressor can compensate for climate change impacts if there is a synergistic interaction. Conversely, if there is an antagonistic interaction, management of local stressors will have the greatest benefits in areas of refuge from climate change. A balanced research agenda, investigating both antagonistic and synergistic interaction types, is needed to inform management priorities.

  16. Managing for interactions between local and global stressors of ecosystems.

    Directory of Open Access Journals (Sweden)

    Christopher J Brown

    Full Text Available Global stressors, including climate change, are a major threat to ecosystems, but they cannot be halted by local actions. Ecosystem management is thus attempting to compensate for the impacts of global stressors by reducing local stressors, such as overfishing. This approach assumes that stressors interact additively or synergistically, whereby the combined effect of two stressors is at least the sum of their isolated effects. It is not clear, however, how management should proceed for antagonistic interactions among stressors, where multiple stressors do not have an additive or greater impact. Research to date has focussed on identifying synergisms among stressors, but antagonisms may be just as common. We examined the effectiveness of management when faced with different types of interactions in two systems--seagrass and fish communities--where the global stressor was climate change but the local stressors were different. When there were synergisms, mitigating local stressors delivered greater gains, whereas when there were antagonisms, management of local stressors was ineffective or even degraded ecosystems. These results suggest that reducing a local stressor can compensate for climate change impacts if there is a synergistic interaction. Conversely, if there is an antagonistic interaction, management of local stressors will have the greatest benefits in areas of refuge from climate change. A balanced research agenda, investigating both antagonistic and synergistic interaction types, is needed to inform management priorities.

  17. Occupancy and Occupants’ Actions

    DEFF Research Database (Denmark)

    Schweiker, Marcel; Carlucci, Salvatore; Andersen, Rune

    2018-01-01

    to study, measure, and ultimately model. The categories are physiological, individual, environmental, and spatial adjustments. Third, a list of adaptive and non-adaptive triggers together with contextual factors that could influence occupant behavior is presented. Individual elements are further grouped...... into physical environmental, physiological, psychological, and social aspects. Finally, a comprehensive table of studies related to occupant behavior and the corresponding significant and non-significant predictors, based on an extensive literature review, is shown. This table highlights areas of research where......Occupants’ presence and actions within the built environment are crucial aspects related to understanding variations in energy use. Within this chapter, first, a nomenclature for the field of research dealing with occupants in buildings is defined. This nomenclature distinguishes between occupants...

  18. Occupants' window opening behaviour

    DEFF Research Database (Denmark)

    Fabi, Valentina; Andersen, Rune Korsholm; Corgnati, Stefano

    2012-01-01

    Energy consumption in buildings is influenced by several factors related to the building properties and the building controls, some of them highly connected to the behaviour of their occupants.In this paper, a definition of items referring to occupant behaviour related to the building control...... systems is proposed, based on studies presented in literature and a general process leading to the effects on energy consumptions is identified.Existing studies on the topic of window opening behaviour are highlighted and a theoretical framework to deal with occupants' interactions with building controls......, aimed at improving or maintaining the preferred indoor environmental conditions, is elaborated. This approach is used to look into the drivers for the actions taken by the occupants (windows opening and closing) and to investigate the existing models in literature of these actions for both residential...

  19. Occupational Health

    Science.gov (United States)

    Occupational health problems occur at work or because of the kind of work you do. These problems can include ... by exposure to radiation Exposure to germs in health care settings Good job safety and prevention practices ...

  20. Occupational cancer

    International Nuclear Information System (INIS)

    Choril, A.C.; McCracken, W.J.; Dowd, E.C.; Stewart, Charles; Burton, D.F.; Dyer, D.W.

    1981-01-01

    This paper reviews the experience of the Workmen's Compensation Board of Ontario in identifying cases of cancer that could be attributed to occupational hazards. Workers' claims for compensation are allowed if there is reasonable medical evidence that their cancer was caused by exposure to risk factors associated with their occupation. Details of the types of cancers associated with specific carcinogens or fields of employment are discussed. About 50% of the cases were related to exposure in particular industrial operations that functioned for relatively brief periods. The number of deaths from cancer identified as being caused by occupational factors is compared with the total for cancer from all causes in Ontario during the period 1971 through 1975. Although all workers eligible for compensation may not have been identified, the data suggest that less than 1% is presently caused by occupational factors

  1. Occupational Cancer

    Science.gov (United States)

    ... November 3, 2015 Content source: National Institute for Occupational Safety and Health Division of Surveillance, Hazard Evaluations, and Field Studies ... Fear Act OIG 1600 Clifton Road Atlanta , GA 30329-4027 ...

  2. Occupational health

    CERN Document Server

    Fingret, Dr Ann

    2013-01-01

    Offers a comprehensive view of health and safety issues at work. An invaluable resource for managers, personnel professionals and occupational health practitioners. Recommended by the Institute of Personnel Management.

  3. Occupational cancer

    International Nuclear Information System (INIS)

    Nelson, N.

    1987-01-01

    Cancer resulting from occupational exposure is now receiving major attention, focusing on identification, regulation, and control of cancer-causing agents. Such cancer can result from exposure to chemicals and ionizing and nonionizing radiation. Extended exposure (often years) and an extended latent period of perhaps decades may intervene before tumor appearance. Although the actual extent of occupational cancer is in debate, estimates have ranged from 4 to 15 per cent of all cancer

  4. Occupational health

    OpenAIRE

    Coosemans, R.

    1997-01-01

    Health at work and healthy work environments are among the most valuable assets of individuals, communities and countries. Nowadays, new broader approach is promoted, recognizing the fact that occupational health is a key, but not a unique element of workers’ health. Workers health is a public health approach to resolving the health problems of working populations including all determinants of health recognized as targets of risk management. It focuses on primary prevention of occupational an...

  5. Recovery experiences during vacation and their association with job stressors and health

    Directory of Open Access Journals (Sweden)

    Diana Pereira

    2017-04-01

    Full Text Available Vacations offer opportunities for recovery from work-related stress. However, little is known about the impact of job stressors on recovery experiences during vacation, such as psychological detachment and relaxation. This study investigated detachment and relaxation to mediate the influence of job stressors prior to vacation on recovery during vacation. A total of 136 employees from various occupations completed a questionnaire on their ability to relax and mentally detach from work during a recent vacation. Participants rated perceived time pressure and social exclusion at work prior to their vacation as well as any psychosomatic health complaints or sleep problems during vacation. The results of bootstrap mediation analysis confirmed the mediating role of recovery experiences. The association between job stressors and sleep problems was fully mediated by detachment and relaxation, whereas the association between social exclusion and psychosomatic complaints was fully mediated by relaxation. Furthermore, relaxation partially mediated the association between time pressure and psychosomatic complaints. Not only should the ability of employees to relax and mentally detach be fostered, but job stressors should be reduced in order to allow employees to reach optimal recovery during vacation.

  6. Physical and Organizational Job Stressors in Pregnancy and Associations With Primary Cesarean Deliveries.

    Science.gov (United States)

    Guendelman, Sylvia; Gemmill, Alison; Hosang, Nap; MacDonald, Leslie A

    2017-06-01

    The aim of this study was to assess the relationship between exposure to physical and organizational job stressors during pregnancy and cesarean delivery. We sampled 580 employed women in California who participated in a nested population-based case-control study of birth outcomes. Adjusted multivariate regression analyses estimated associations between heavy lifting, frequent bending, high noise, extreme temperature, prolonged standing and organizational stressors (shift work, inflexible schedules, effort-reward ratio), and primary cesarean (vs vaginal) delivery, controlling for covariates. Women occupationally exposed had higher odds of cesarean. Those exposed to daily manual lifting more than 15 pounds [adjusted odds ratio = 2.54; 95% confidence interval (95% CI) 1.21 to 5.32] and at least four physical job stressors (adjusted odds ratio = 3.49; 95% CI 1.21 to 10.09) had significantly elevated odds of cesarean delivery. Exposed morbid women experienced greater risk; risk was lower among those with schedule flexibility. Associations were found between modifiable exposure to physical job stressors during pregnancy and cesarean delivery.

  7. Marital Quality for Men and Women in Stepfamilies: Examining the Role of Economic Pressure, Common Stressors, and Stepfamily-Specific Stressors

    Science.gov (United States)

    Schramm, David G.; Adler-Baeder, Francesca

    2012-01-01

    Although economic pressure and family stress models have been examined with samples of men and women in first marriages, previous models have neglected to focus on men and women in stepfamilies and to examine stress sources unique to stepfamilies. This study examines the effect of economic pressure on both common stressors and stepfamily-specific…

  8. Randomised controlled trial of a psychiatric consultation model for treatment of common mental disorder in the occupational health setting

    Directory of Open Access Journals (Sweden)

    de Jong Fransina J

    2007-02-01

    Full Text Available Abstract Background Common mental disorders are the most prevalent of all mental disorders, with the highest burden in terms of work absenteeism and utilization of health care services. Evidence-based treatments are available, but recognition and treatment could be improved, especially in the occupational health setting. The situation in this setting has recently changed in the Netherlands because of new legislation, which has resulted in reduced sickness absence. Severe mental disorder has now become one of the main causes of work absenteeism. Occupational physicians (OPs are expected to take an active role in diagnosis and treatment, and seem to be in need of support for a new approach to handle cases of more complex mental disorders. Psychiatric consultation can be a collaborative care model to achieve this. Methods/design This is a two-armed cluster-randomized clinical trial, with randomization among OPs. Forty OPs in two big companies providing medical care for multiple companies will be randomized to either the intervention group, i.e. psychiatric consultation embedded in a training programme, or the control group, i.e. only training aimed at recognition and providing Care As Usual. 60 patients will be included who have been absent from work for 6–52 weeks and who, after screening and a MINI interview, are diagnosed with depressive disorder, anxiety disorder or somatoform disorder based on DSM-IV criteria. Baseline measurements and follow up measurements (at 3 months and 6 months will be assessed with questionnaires and an interview. The primary outcome measure is level of general functioning according to the SF-20. Secondary measures are severity of the mental disorder according to the PHQ and the SCL-90, quality of life (EQ-D5, measures of Return To Work and cost-effectiveness of the treatment assessed with the TiC-P. Process measures will be adherence to the treatment plan and assessment of the treatment provided by the Psychiatric

  9. Predicting spatial and temporal gene expression using an integrative model of transcription factor occupancy and chromatin state.

    Directory of Open Access Journals (Sweden)

    Bartek Wilczynski

    Full Text Available Precise patterns of spatial and temporal gene expression are central to metazoan complexity and act as a driving force for embryonic development. While there has been substantial progress in dissecting and predicting cis-regulatory activity, our understanding of how information from multiple enhancer elements converge to regulate a gene's expression remains elusive. This is in large part due to the number of different biological processes involved in mediating regulation as well as limited availability of experimental measurements for many of them. Here, we used a Bayesian approach to model diverse experimental regulatory data, leading to accurate predictions of both spatial and temporal aspects of gene expression. We integrated whole-embryo information on transcription factor recruitment to multiple cis-regulatory modules, insulator binding and histone modification status in the vicinity of individual gene loci, at a genome-wide scale during Drosophila development. The model uses Bayesian networks to represent the relation between transcription factor occupancy and enhancer activity in specific tissues and stages. All parameters are optimized in an Expectation Maximization procedure providing a model capable of predicting tissue- and stage-specific activity of new, previously unassayed genes. Performing the optimization with subsets of input data demonstrated that neither enhancer occupancy nor chromatin state alone can explain all gene expression patterns, but taken together allow for accurate predictions of spatio-temporal activity. Model predictions were validated using the expression patterns of more than 600 genes recently made available by the BDGP consortium, demonstrating an average 15-fold enrichment of genes expressed in the predicted tissue over a naïve model. We further validated the model by experimentally testing the expression of 20 predicted target genes of unknown expression, resulting in an accuracy of 95% for temporal

  10. Discrimination, Other Psychosocial Stressors, and Self-Reported Sleep Duration and Difficulties

    Science.gov (United States)

    Slopen, Natalie; Williams, David R.

    2014-01-01

    Objectives: To advance understanding of the relationship between discrimination and sleep duration and difficulties, with consideration of multiple dimensions of discrimination, and attention to concurrent stressors; and to examine the contribution of discrimination and other stressors to racial/ ethnic differences in these outcomes. Design: Cross-sectional probability sample. Setting: Chicago, IL. Participants: There were 2,983 black, Hispanic, and white adults. Measurements and Results: Outcomes included self-reported sleep duration and difficulties. Discrimination, including racial and nonracial everyday and major experiences of discrimination, workplace harassment and incivilities, and other stressors were assessed via questionnaire. In models adjusted for sociodemographic characteristics, greater exposure to racial (β = -0.14)) and nonracial (β = -0.08) everyday discrimination, major experiences of discrimination attributed to race/ethnicity (β = -0.17), and workplace harassment and incivilities (β = -0.14) were associated with shorter sleep (P stressors (i.e., acute events, childhood adversity, and financial, community, employment, and relationship stressors). Racial (β = 0.04) and non-racial (β = 0.05) everyday discrimination and racial (β = 0.04) and nonracial (β = 0.04) major experiences of discrimination, and workplace harassment and incivilities (β = 0.04) were also associated with more (log) sleep difficulties, and associations between racial and nonracial everyday discrimination and sleep difficulties remained after adjustment for other stressors (P 0.05). Conclusions: Discrimination was associated with shorter sleep and more sleep difficulties, independent of socioeconomic status and other stressors, and may account for some of the racial/ethnic differences in sleep. Citation: Slopen N; Williams DR. Discrimination, other psychosocial stressors, and self-reported sleep duration and difficulties. SLEEP 2014;37(1):147-156. PMID:24381373

  11. Psychosocial stressors and cigarette smoking among African American adults in midlife.

    Science.gov (United States)

    Slopen, Natalie; Dutra, Lauren M; Williams, David R; Mujahid, Mahasin S; Lewis, Tené T; Bennett, Gary G; Ryff, Carol D; Albert, Michelle A

    2012-10-01

    Psychosocial stress is a significant risk factor for smoking, and Blacks experience higher levels of psychosocial stress relative to other racial/ethnic groups. Limited research has comprehensively examined psychosocial stressors in relation to smoking among Blacks. We examined psychosocial stressors in relation to smoking status (current, previous, and never) in middle-aged Blacks (34-85 years, n = 592) from Milwaukee, Wisconsin, a subset of the Midlife in the United States Study II (2004-2006). Eleven stressor domains were assessed, including psychological and physical work stress, work-family conflict, perceived inequality, relationship stress, neighborhood stress, discrimination, financial stress, recent problems, stressful events, and childhood adversity. We also calculated a cumulative score. Multinomial models were adjusted for age, gender, education, and income. Seven of the 11 stressors and the cumulative score were associated with higher odds of being a current smoker compared with a never-smoker: neighborhood, financial, relationship, and psychological work stress, perceived inequality, stressful events, childhood adversity (p values <.05; ORs ranged from 1.28 to 1.77). Three stressors and the cumulative score were associated with higher odds of being a previous smoker versus a never-smoker (p < .05). Individuals who scored in the top quartile on 5 or more stressors were 3.74 (95% CI = 2.09-6.71) times as likely to be current smokers, and more than twice as likely to be previous smokers, compared with individuals with no high stressors. These results demonstrate a strong relationship between stress and smoking among urban middle-aged Blacks and suggest that cessation programs should address modifiable individual and community-level stressors.

  12. Negative Aging Attitudes Predict Greater Reactivity to Daily Stressors in Older Adults.

    Science.gov (United States)

    Bellingtier, Jennifer A; Neupert, Shevaun D

    2016-08-03

    In order to understand conflicting findings regarding the emotional reactions of older adults to daily stressors, we examined the possibility that negative aging attitudes could function as an important individual differences factor related to stressor reactivity. Using a daily dairy design, we examined the aging attitudes of 43 older adults reporting on 380 total days. Participants reported their aging attitudes on Day 1, followed by their stressor exposure and negative affect on Days 2-9. Covariates included age, gender, education, and personality. Using multilevel modeling, our results suggest that individuals with more positive aging attitudes report consistent levels of affect across study days regardless of stressors, whereas those with more negative aging attitudes reported increased emotional reactivity to daily stressors. Positive aging attitudes may serve as a resource that helps buffer reactions to daily stressors. © 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.

  13. Density dependence governs when population responses to multiple stressors are magnified or mitigated.

    Science.gov (United States)

    Hodgson, Emma E; Essington, Timothy E; Halpern, Benjamin S

    2017-10-01

    Population endangerment typically arises from multiple, potentially interacting anthropogenic stressors. Extensive research has investigated the consequences of multiple stressors on organisms, frequently focusing on individual life stages. Less is known about population-level consequences of exposure to multiple stressors, especially when exposure varies through life. We provide the first theoretical basis for identifying species at risk of magnified effects from multiple stressors across life history. By applying a population modeling framework, we reveal conditions under which population responses from stressors applied to distinct life stages are either magnified (synergistic) or mitigated. We find that magnification or mitigation critically depends on the shape of density dependence, but not the life stage in which it occurs. Stressors are always magnified when density dependence is linear or concave, and magnified or mitigated when it is convex. Using Bayesian numerical methods, we estimated the shape of density dependence for eight species across diverse taxa, finding support for all three shapes. © 2017 by the Ecological Society of America.

  14. Chronic stressors and trauma: prospective influences on the course of bipolar disorder

    Science.gov (United States)

    Gershon, A.; Johnson, S. L.; Miller, I.

    2013-01-01

    Background Exposure to life stress is known to adversely impact the course of bipolar disorder. Few studies have disentangled the effects of multiple types of stressors on the longitudinal course of bipolar I disorder. This study examines whether severity of chronic stressors and exposure to trauma are prospectively associated with course of illness among bipolar patients. Method One hundred and thirty-one participants diagnosed with bipolar I disorder were recruited through treatment centers, support groups and community advertisements. Severity of chronic stressors and exposure to trauma were assessed at study entry with in-person interviews using the Bedford College Life Event and Difficulty Schedule (LEDS). Course of illness was assessed by monthly interviews conducted over the course of 24 months (over 3000 assessments). Results Trauma exposure was related to more severe interpersonal chronic stressors. Multiple regression models provided evidence that severity of overall chronic stressors predicted depressive but not manic symptoms, accounting for 7.5% of explained variance. Conclusions Overall chronic stressors seem to be an important determinant of depressive symptoms within bipolar disorder, highlighting the importance of studying multiple forms of life stress. PMID:23419615

  15. A review of hydrological and chemical stressors in the Adige catchment and its ecological status.

    Science.gov (United States)

    Chiogna, Gabriele; Majone, Bruno; Cano Paoli, Karina; Diamantini, Elena; Stella, Elisa; Mallucci, Stefano; Lencioni, Valeria; Zandonai, Fabiana; Bellin, Alberto

    2016-01-01

    Quantifying the effects of multiple stressors on Alpine freshwater ecosystems is challenging, due to the lack of tailored field campaigns for the contemporaneous measurement of hydrological, chemical and ecological parameters. Conducting exhaustive field campaigns is costly and hence most of the activities so far have been performed addressing specific environmental issues. An accurate analysis of existing information is therefore useful and necessary, to identify stressors that may act in synergy and to design new field campaigns. We present an extended review of available studies and datasets concerning the hydrological, chemical and ecological status of the Adige, which is the second longest river and the third largest river basin in Italy. The most relevant stressors are discussed in the light of the information extracted from a large number of studies. The detailed analysis of these studies identified that hydrological alterations caused by hydropower production are the main source of stress for the freshwater ecosystems in the Adige catchment. However, concurrent effects with other stressors, such as the release of pollutants from waste water treatment plants or from agricultural and industrial activities, have not been explored at depth, so far. A wealth of available studies address a single stressor separately without exploring their concurrent effect. It is concluded that a combination of extended experimental field campaigns, focusing on the coupled effects of multiple stressors, and modeling activities is highly needed in order to quantify the impact of the multifaceted human pressures on freshwater ecosystems in the Adige river. Copyright © 2015. Published by Elsevier B.V.

  16. Chronic stressors and trauma: prospective influences on the course of bipolar disorder.

    Science.gov (United States)

    Gershon, A; Johnson, S L; Miller, I

    2013-12-01

    Exposure to life stress is known to adversely impact the course of bipolar disorder. Few studies have disentangled the effects of multiple types of stressors on the longitudinal course of bipolar I disorder. This study examines whether severity of chronic stressors and exposure to trauma are prospectively associated with course of illness among bipolar patients. One hundred and thirty-one participants diagnosed with bipolar I disorder were recruited through treatment centers, support groups and community advertisements. Severity of chronic stressors and exposure to trauma were assessed at study entry with in-person interviews using the Bedford College Life Event and Difficulty Schedule (LEDS). Course of illness was assessed by monthly interviews conducted over the course of 24 months (over 3000 assessments). Trauma exposure was related to more severe interpersonal chronic stressors. Multiple regression models provided evidence that severity of overall chronic stressors predicted depressive but not manic symptoms, accounting for 7.5% of explained variance. Overall chronic stressors seem to be an important determinant of depressive symptoms within bipolar disorder, highlighting the importance of studying multiple forms of life stress.

  17. Childhood Stress : Stressors, Coping, and Factors.

    NARCIS (Netherlands)

    Nijboer, J.M.

    2007-01-01

    Burnout is a matter of imbalance in life very often (Nijboer, 2006). In order to know more about imbalance and exhaustion in children, stress and coping in children will be investigated in this literature study. The goal is to identify common childhood stressors, the ways children cope with stress,

  18. Habituation to a stressor predicts adolescents' adiposity

    Science.gov (United States)

    Background and Objectives: Stress is associated with gains in adiposity. One factor that determines how much stress is experienced is how quickly an adolescent reduces responding (habituates) across repeated stressors. The purpose of this study was to determine the association of body mass index pe...

  19. Overview of Atherosclerosis and Chemical Stressors

    Science.gov (United States)

    Dr. Cascio’s presentation at the workshop titled, “titled “Understanding the Combined Effects of Environmental Chemical and Non-Chemical Stressors: Atherosclerosis as a Model” will highlight atherosclerosis’s rapidly growing role as a cause of increa...

  20. Daily Stressors in Primary Education Students

    Science.gov (United States)

    Fernández-Baena, F. Javier; Trianes, María V.; Escobar, Milagros; Blanca, María J.; Muñoz, Ángela M.

    2015-01-01

    Daily stress can have a bearing on children's emotional and academic development. This study aimed to assess daily stressors and to determine their prevalence among primary education students, taking into account their gender, academic year, social adaptation, and the school location. A sample of 7,354 Spanish schoolchildren aged between 6 and 13…

  1. District Stressors and Teacher Evaluation Ratings

    Science.gov (United States)

    Lenhoff, Sarah Winchell; Pogodzinski, Ben; Mayrowetz, David; Superfine, Benjamin Michael; Umpstead, Regina R.

    2018-01-01

    Purpose: Federal and state policymakers in the USA have sought to better differentiate the performance of K-12 teachers by enacting more rigorous evaluation policies. The purpose of this paper is to investigate whether these policies are working as intended and explore whether district stressors such as funding, enrollment, and governance are…

  2. Occupational stress and coping strategies among emergency department nurses of China.

    Science.gov (United States)

    Lu, Dong-Mei; Sun, Ning; Hong, Su; Fan, Yu-ying; Kong, Fan-ying; Li, Qiu-jie

    2015-08-01

    Emergency department(ED) nurses work in a rapidly changing environment with patients that have wide variety of conditions. Occupational stress in emergency department nurses is a common problem. The purpose of this study was to describe the relationship between coping strategies and occupational stress among ED nurses in China. A correlational, cross-sectional design was adopted. Two questionnaires were given to a random sample of 127 ED nurses registered at the Heilongjiang Nurses' Association. Data were collected from the nurses that worked in the ED of five general hospitals in Harbin China. Occupational stress and coping strategies were measured by two questionnaires. A multiple regression model was applied to analyze the relationship between stress and coping strategies. The stressors of ED nurses mainly come from the ED specialty of nursing (2.97±0.55), workload and time distribution (2.97±0.58). The mean score of positive coping strategies was 2.19±0.35, higher than the norm (1.78±0.52). The mean score of negative coping strategies was 1.20±0.61, lower than the norm (1.59±0.66), both had significant statistical difference (Pwork, criticism, instrument equipment shortage, night shift, rank of professional were the influence factors about occupational stress to positive coping styles. Too much documents work, and medical insurance for ED nurses were the influential factors on occupational stress to negative coping styles. This study identified several factors associated with occupational stress in ED nurses. These results could be used to guide nurse managers of ED nurses to reduce work stress. The managers could pay more attention to the ED nurse's coping strategies which can further influence their health state and quality of nursing care. Reducing occupational stress and enhancing coping strategies are vital not only for encouraging nurses but also for the future of nursing development. Copyright © 2015. Published by Elsevier Inc.

  3. Development and Validation of the Total HUman Model for Safety (THUMS) Version 5 Containing Multiple 1D Muscles for Estimating Occupant Motions with Muscle Activation During Side Impacts.

    Science.gov (United States)

    Iwamoto, Masami; Nakahira, Yuko

    2015-11-01

    Accurate prediction of occupant head kinematics is critical for better understanding of head/face injury mechanisms in side impacts, especially far-side occupants. In light of the fact that researchers have demonstrated that muscle activations, especially in neck muscles, can affect occupant head kinematics, a human body finite element (FE) model that considers muscle activation is useful for predicting occupant head kinematics in real-world automotive accidents. In this study, we developed a human body FE model called the THUMS (Total HUman Model for Safety) Version 5 that contains 262 one-dimensional (1D) Hill-type muscle models over the entire body. The THUMS was validated against 36 series of PMHS (Post Mortem Human Surrogate) and volunteer test data in this study, and 16 series of PMHS and volunteer test data on side impacts are presented. Validation results with force-time curves were also evaluated quantitatively using the CORA (CORrelation and Analysis) method. The validation results suggest that the THUMS has good biofidelity in the responses of the regional or full body for side impacts, but relatively poor biofidelity in its local level of responses such as brain displacements. Occupant kinematics predicted by the THUMS with a muscle controller using 22 PID (Proportional-Integral- Derivative) controllers were compared with those of volunteer test data on low-speed lateral impacts. The THUMS with muscle controller reproduced the head kinematics of the volunteer data more accurately than that without muscle activation, although further studies on validation of torso kinematics are needed for more accurate predictions of occupant head kinematics.

  4. Interpersonal workplace stressors and well-being: a multi-wave study of employees with and without arthritis.

    Science.gov (United States)

    Potter, Phillip T; Smith, Bruce W; Strobel, Kari R; Zautra, Alex J

    2002-08-01

    The within-person influence of interpersonal stressors on affective well-being and physical well-being was investigated for 109 women with and without arthritis. Participants were interviewed on a weekly basis for 12 consecutive weeks, and the prospective data were analyzed by using hierarchical linear modeling. Overall, interpersonal workplace stressors independently predicted both well-being outcomes. Interpersonal stressors outside the workplace were related to negative affect but not to arthritis symptoms. Compared with healthy controls, arthritis patients' ratings of negative affect were equally reactive to workplace stressors. Neuroticism did not moderate stressor reactivity for either dependent variable but did predict mean levels of negative affect. The data support the hypothesis that the psychosocial environment of the workplace contributes unique effects on well-being.

  5. The relationship between length of vocational disability, psychiatric illness, life stressors and sociodemographic variables.

    Science.gov (United States)

    Chandarana, P; Jackson, T; Kohr, R; Iezzi, T

    1997-01-01

    The primary objective of this study was to examine the relationship between vocational disability, psychiatric illness, life stressors and sociodemographic factors. Information on a variety of variables was obtained from insurance files of 147 subjects who had submitted claims for monetary compensation on grounds of psychiatric symptoms. The majority of subjects received a diagnosis of mood disorder or anxiety disorder. Extended vocational disability was associated with longer duration of psychiatric illness, rating of poorer prognosis by the treating physician, and lower income and occupational levels. Individuals with recent onset of disability reported more stressors than those experiencing extended disability. Although longer duration of psychiatric illness was associated with vocational disability, other variables play an important role in accounting for extended vocational disability.

  6. Habitat Modeling of Alien Plant Species at Varying Levels of Occupancy

    Directory of Open Access Journals (Sweden)

    Jennifer A. Brown

    2012-09-01

    Full Text Available Distribution models of invasive plants are very useful tools for conservation management. There are challenges in modeling expanding populations, especially in a dynamic environment, and when data are limited. In this paper, predictive habitat models were assessed for three invasive plant species, at differing levels of occurrence, using two different habitat modeling techniques: logistic regression and maximum entropy. The influence of disturbance, spatial and temporal heterogeneity, and other landscape characteristics is assessed by creating regional level models based on occurrence records from the USDA Forest Service’s Forest Inventory and Analysis database. Logistic regression and maximum entropy models were assessed independently. Ensemble models were developed to combine the predictions of the two analysis approaches to obtain a more robust prediction estimate. All species had strong models with Area Under the receiver operator Curve (AUC of >0.75. The species with the highest occurrence, Ligustrum spp., had the greatest agreement between the models (93%. Lolium arundinaceum had the most disagreement between models at 33% and the lowest AUC values. Overall, the strength of integrative modeling in assessing and understanding habitat modeling was demonstrated.

  7. Stressors and their Influence on Job Performance of Career ...

    African Journals Online (AJOL)

    Stressors and their Influence on Job Performance of Career Administrative Staff in ... African Research Review ... Abstract. The purpose of this study was to determine stressors and how they influence university career administrative staff in the ...

  8. Community Level Stressors and Their Impacts on Food Contamination

    Science.gov (United States)

    Research is needed to understand a community’s food resources, utilization of those resources, and how the built and natural environment impact access to resources and potential chemical exposures. This research will identify stressors, relationships between those stressors...

  9. Work environment stressors and personnel efficacy in Nigeria's ...

    African Journals Online (AJOL)

    Work environment stressors and personnel efficacy in Nigeria's maritime industry. ... Journal Home > Vol 15, No 1 (2017) > ... employees and corporate organizations need to manage stress by identifying the stressors and stress levels.

  10. Reactivity to Daily Stressors in Adulthood: The Importance of Stressor Type in Characterizing Risk Factors

    OpenAIRE

    Hay, Elizabeth L.; Diehl, Manfred

    2010-01-01

    This study examined daily stressors in adults aged 18 to 89 years (M = 49.6 years) over 30 days. We examined the role of individual factors (i.e., age, self-concept differentiation, perceived control) in physical and psychological reactivity to interpersonal, network, home, and health stressors. Findings were consistent with the perspective that adults were less reactive to stress on days they felt in control and that younger adults and adults with high self-concept differentiation (SCD) were...

  11. A model of Occupational Safety and Health Management System (OSHMS) for promoting and controlling health and safety in textile industry.

    Science.gov (United States)

    Manimaran, S; Rajalakshmi, R; Bhagyalakshmi, K

    2015-01-01

    The development of Occupational Safety and Health Management System in textile industry will rejuvenate the workers and energize the economy as a whole. In India, especially in Tamil Nadu, approximately 1371 textile business is running with the help of 38,461 workers under Ginning, Spinning, Weaving, Garment and Dyeing sectors. Textile industry of contributes to the growth of Indian economy but it fails to foster education and health as key components of human development and help new democracies. The present work attempts to measure and develop OSHMS which reduce the hazards and risk involved in textile industry. Among all other industries textile industry is affected by enormous hazards and risk because of negligence by management and Government. It is evident that managements are not abiding by law when an accident has occurred. Managements are easily deceiving workers and least bothered about the Quality of Work Life (QWL). A detailed analysis of factors promoting safety and health to the workers has been done by performing confirmatory factor analysis, evaluating Risk Priority Number and the framework of OHMS has been conceptualized using Structural Equation Model. The data have been collected using questionnaire and interview method. The study finds occupation health for worker in Textile industry is affected not only by safety measure but also by technology and management. The work shows that difficulty in identifying the cause and effect of hazards, the influence of management in controlling and promoting OSHMS under various dimensions. One startling fact is existence of very low and insignificance correlation between health factors and outcome.

  12. Life Change Units (LCU Rating as Stressors in Iranian Hospitals’ Nurses

    Directory of Open Access Journals (Sweden)

    Hossein Dargahi

    2012-02-01

    Full Text Available Healthcare workers suffer from work-related or occupational stress. This can lead to severe distress, burnout or physical illness, and finally to decrease quality of work life and services provision. Nurses must be aware of retential stressors, because they add to the cumulative effect of other stressful events. Holmes and Rahe both found a relationship between life change unit as stressors and health changes. This research reported here aims to measure the life change units as stressors among Iranian Hospitals Nurses by LCU rating. A cross - sectional, descriptive and analytical study was conducted among 389 nurses working in 15 teaching hospitals in Tehran, Iran. The respondents were asked to select each of 54 events that cause stress ranked in order of their life change units developed by Holmes and Rahe as stress scale. Before beginning the main study, the reliability and coincidental validity was performed. All data were analyzed using SPSS for windows version 18, t-test, Anova statistical methods. Approximately, half of the nurses associated major mortgage, foreclosure of mortgage or loan. More than 50% of the Iranian nurses had 150-300 and more than 300 LCU rating which had the chance to expose to extremely serious risk to health.Iranian hospitals nurses suffer from stress that caused by Life Change Units organizational factors such as change in the financial state, change in the work environment and major mortgage. We recommend to Iranian nursing policy-makers to choose strategies to help nurses cope effectively with workplace stressors. Nursing managers and / or nursing management should develop strategies to address and improve the quality of working conditions for nurses in the hospitals. Providing educational and career prospects can contribute to decrease nurses occupational stress level, the maintaining their work ability.

  13. Characterizing the Life Stressors of Children of Alcoholic Parents

    OpenAIRE

    Hussong, Andrea M.; Bauer, Daniel J.; Huang, Wenjing; Chassin, Laurie; Sher, Kenneth J.; Zucker, Robert A.

    2008-01-01

    The current study examined differences between children of alcoholic (COAs) and non-alcoholic parents in their experience of negative life events across three, longitudinal studies together spanning the first three decades of life. We posited that COAs would differ from their peers in the life domains in which they are vulnerable to stressors, in the recurrence of stressors, and in the severity of stressors. Scale- and item-level analyses of adjusted odds-ratios based on stressors across seve...

  14. Cost Effectiveness of the Instrumentalism in Occupational Therapy (IOT) Conceptual Model as a Guide for Intervention with Adolescents with Emotional and Behavioral Disorders (EBD)

    Science.gov (United States)

    Ikiugu, Moses N.; Anderson, Lynne

    2007-01-01

    The purpose of this paper was to demonstrate the cost-effectiveness of using the Instrumentalism in Occupational Therapy (IOT) conceptual practice model as a guide for intervention to assist teenagers with emotional and behavioral disorders (EBD) transition successfully into adulthood. The cost effectiveness analysis was based on a project…

  15. Job Stressors, Organizational Innovation Climate, and Employees' Innovative Behavior

    Science.gov (United States)

    Ren, Feifei; Zhang, Jinghuan

    2015-01-01

    This study attempted to examine the influence of job stressors and organizational innovation climate on employees' innovative behavior. Data were obtained from 282 employees in 4 cities of China. Results indicated that the nature of stressors matters in predicting employees' idea generation. Specifically, stressors that employees tend to appraise…

  16. Predicting occupancy for pygmy rabbits in Wyoming: an independent evaluation of two species distribution models

    Science.gov (United States)

    Germaine, Stephen S.; Ignizio, Drew; Keinath, Doug; Copeland, Holly

    2014-01-01

    Species distribution models are an important component of natural-resource conservation planning efforts. Independent, external evaluation of their accuracy is important before they are used in management contexts. We evaluated the classification accuracy of two species distribution models designed to predict the distribution of pygmy rabbit Brachylagus idahoensis habitat in southwestern Wyoming, USA. The Nature Conservancy model was deductive and based on published information and expert opinion, whereas the Wyoming Natural Diversity Database model was statistically derived using historical observation data. We randomly selected 187 evaluation survey points throughout southwestern Wyoming in areas predicted to be habitat and areas predicted to be nonhabitat for each model. The Nature Conservancy model correctly classified 39 of 77 (50.6%) unoccupied evaluation plots and 65 of 88 (73.9%) occupied plots for an overall classification success of 63.3%. The Wyoming Natural Diversity Database model correctly classified 53 of 95 (55.8%) unoccupied plots and 59 of 88 (67.0%) occupied plots for an overall classification success of 61.2%. Based on 95% asymptotic confidence intervals, classification success of the two models did not differ. The models jointly classified 10.8% of the area as habitat and 47.4% of the area as nonhabitat, but were discordant in classifying the remaining 41.9% of the area. To evaluate how anthropogenic development affected model predictive success, we surveyed 120 additional plots among three density levels of gas-field road networks. Classification success declined sharply for both models as road-density level increased beyond 5 km of roads per km-squared area. Both models were more effective at predicting habitat than nonhabitat in relatively undeveloped areas, and neither was effective at accounting for the effects of gas-energy-development road networks. Resource managers who wish to know the amount of pygmy rabbit habitat present in an

  17. Using the Job Burden-Capital Model of Occupational Stress to Predict Depression and Well-Being among Electronic Manufacturing Service Employees in China

    Directory of Open Access Journals (Sweden)

    Chao Wang

    2016-08-01

    Full Text Available Background: This study aimed to identify the association between occupational stress and depression-well-being by proposing a comprehensive and flexible job burden-capital model with its corresponding hypotheses. Methods: For this research, 1618 valid samples were gathered from the electronic manufacturing service industry in Hunan Province, China; self-rated questionnaires were administered to participants for data collection after obtaining their written consent. The proposed model was fitted and tested through structural equation model analysis. Results: Single-factor correlation analysis results indicated that coefficients between all items and dimensions had statistical significance. The final model demonstrated satisfactory global goodness of fit (CMIN/DF = 5.37, AGFI = 0.915, NNFI = 0.945, IFI = 0.952, RMSEA = 0.052. Both the measurement and structural models showed acceptable path loadings. Job burden and capital were directly associated with depression and well-being or indirectly related to them through personality. Multi-group structural equation model analyses indicated general applicability of the proposed model to basic features of such a population. Gender, marriage and education led to differences in the relation between occupational stress and health outcomes. Conclusions: The job burden-capital model of occupational stress-depression and well-being was found to be more systematic and comprehensive than previous models.

  18. Using the Job Burden-Capital Model of Occupational Stress to Predict Depression and Well-Being among Electronic Manufacturing Service Employees in China.

    Science.gov (United States)

    Wang, Chao; Li, Shuang; Li, Tao; Yu, Shanfa; Dai, Junming; Liu, Xiaoman; Zhu, Xiaojun; Ji, Yuqing; Wang, Jin

    2016-08-12

    This study aimed to identify the association between occupational stress and depression-well-being by proposing a comprehensive and flexible job burden-capital model with its corresponding hypotheses. For this research, 1618 valid samples were gathered from the electronic manufacturing service industry in Hunan Province, China; self-rated questionnaires were administered to participants for data collection after obtaining their written consent. The proposed model was fitted and tested through structural equation model analysis. Single-factor correlation analysis results indicated that coefficients between all items and dimensions had statistical significance. The final model demonstrated satisfactory global goodness of fit (CMIN/DF = 5.37, AGFI = 0.915, NNFI = 0.945, IFI = 0.952, RMSEA = 0.052). Both the measurement and structural models showed acceptable path loadings. Job burden and capital were directly associated with depression and well-being or indirectly related to them through personality. Multi-group structural equation model analyses indicated general applicability of the proposed model to basic features of such a population. Gender, marriage and education led to differences in the relation between occupational stress and health outcomes. The job burden-capital model of occupational stress-depression and well-being was found to be more systematic and comprehensive than previous models.

  19. Using the Job Burden-Capital Model of Occupational Stress to Predict Depression and Well-Being among Electronic Manufacturing Service Employees in China

    Science.gov (United States)

    Wang, Chao; Li, Shuang; Li, Tao; Yu, Shanfa; Dai, Junming; Liu, Xiaoman; Zhu, Xiaojun; Ji, Yuqing; Wang, Jin

    2016-01-01

    Background: This study aimed to identify the association between occupational stress and depression-well-being by proposing a comprehensive and flexible job burden-capital model with its corresponding hypotheses. Methods: For this research, 1618 valid samples were gathered from the electronic manufacturing service industry in Hunan Province, China; self-rated questionnaires were administered to participants for data collection after obtaining their written consent. The proposed model was fitted and tested through structural equation model analysis. Results: Single-factor correlation analysis results indicated that coefficients between all items and dimensions had statistical significance. The final model demonstrated satisfactory global goodness of fit (CMIN/DF = 5.37, AGFI = 0.915, NNFI = 0.945, IFI = 0.952, RMSEA = 0.052). Both the measurement and structural models showed acceptable path loadings. Job burden and capital were directly associated with depression and well-being or indirectly related to them through personality. Multi-group structural equation model analyses indicated general applicability of the proposed model to basic features of such a population. Gender, marriage and education led to differences in the relation between occupational stress and health outcomes. Conclusions: The job burden-capital model of occupational stress-depression and well-being was found to be more systematic and comprehensive than previous models. PMID:27529267

  20. Common Occupational Disability Tests and Case Law References: An Ontario MVA perspective on interpretation and best practice methodology supporting a holistic model, Part I of III (Pre-104 IRB).

    Science.gov (United States)

    Salmon, J Douglas; Gouws, Jacques J; Bachmann, Corina Anghel

    2016-05-01

    This three-part paper presents practical holistic models of determining impairment and occupational disability with respect to common "own occupation" and "any occupation" definitions. The models consider physical, emotional and cognitive impairments in unison, and draw upon case law support for empirically based functional assessment of secondary cognitive symptoms arising from psychological conditions, including chronic pain disorders. Case law is presented, primarily in the context of Ontario motor vehicle accident legislation, to demonstrate how triers of fact have addressed occupational disability in the context of chronic pain; and interpreted the "own occupation" and "any occupation" definitions. In interpreting the definitions of "own occupation" and "any occupation", courts have considered various concepts, such as: work as an integrated whole, competitive productivity, demonstrated job performance vs. employment, work adaptation relative to impairment stability, suitable work, retraining considerations, self-employment, and remuneration/socio-economic status. The first segment of the paper reviews the above concepts largely in the context of pre-104 Income Replacement Benefit (IRB) entitlement, while the second segment focuses on post-104 IRB entitlement. In the final segment, the paper presents a critical evaluation of computerized transferable skills analysis (TSAs) in the occupational disability context. By contrast, support is offered for the notion that (neuro) psychovocational assessments and situational work assessments should play a key role in "own occupation" disability determination, even where specific vocational rehabilitation/retraining recommendations are not requested by the referral source (e.g., insurer disability examination).

  1. Stressors and anxiety in dementia caregiving: multiple mediation analysis of rumination, experiential avoidance, and leisure.

    Science.gov (United States)

    Romero-Moreno, R; Losada, A; Márquez-González, M; Mausbach, B T

    2016-11-01

    Despite the robust associations between stressors and anxiety in dementia caregiving, there is a lack of research examining which factors contribute to explain this relationship. This study was designed to test a multiple mediation model of behavioral and psychological symptoms of dementia (BPSD) and anxiety that proposes higher levels of rumination and experiential avoidance and lower levels of leisure satisfaction as potential mediating variables. The sample consisted of 256 family caregivers. In order to test a simultaneously parallel multiple mediation model of the BPSD to anxiety pathway, a PROCESS method was used and bias-corrected and accelerated bootstrapping method was used to test confidence intervals. Higher levels of stressors significantly predicted anxiety. Greater stressors significantly predicted higher levels of rumination and experiential avoidance, and lower levels of leisure satisfaction. These three coping variables significantly predicted anxiety. Finally, rumination, experiential avoidance, and leisure satisfaction significantly mediated the link between stressors and anxiety. The explained variance for the final model was 47.09%. Significant contrasts were found between rumination and leisure satisfaction, with rumination being a significantly higher mediator. The results suggest that caregivers' experiential avoidance, rumination, and leisure satisfaction may function as mechanisms through which BPSD influence on caregivers' anxiety. Training caregivers in reducing their levels of experiential avoidance and rumination by techniques that foster their ability of acceptance of their negative internal experiences, and increase their level of leisure satisfaction, may be helpful to reduce their anxiety symptoms developed by stressors.

  2. Virtual traumatology of pregnant women: the PRegnant car Occupant Model for Impact Simulations (PROMIS).

    Science.gov (United States)

    Auriault, F; Thollon, L; Peres, J; Delotte, J; Kayvantash, K; Brunet, C; Behr, M

    2014-01-03

    This study report documents the development of a finite element (FE) model for analyzing trauma in pregnant women involved in road accidents and help the design of a specific safety device. The model is representative of a 50th percentile pregnant woman at 26 weeks of pregnancy in sitting position. To achieve this, the HUMOS 2 model, which has been validated in a wide range of dynamic tests, was scaled to the morphology of a woman in the 50th percentile and coupled with a model of gravid uterus. During scaling, special attention was paid to the pelvic region which is known to differ considerably in morphological terms between men and women. The gravid uterus model includes a placenta, a fetus, uterosacral ligaments and the amniotic fluid by means of fluid structure interaction formulation. The uterus and the female model were coupled using an original method whereby the growth of an uterus was simulated to compress the abdominal organs in a realistic manner. The model was validated based on experimental tests described in the literature. Additional tests based on abdominal loadings with a seatbelt on Post Mortem Human Surrogates (PMHS) coupled to silicone uterus were also performed. Results highlighted the role of the possible interaction of the fetus in the pregnant woman abdominal response. Experimental corridors taking into account the presence of this fetus could therefore be proposed. © 2013 Elsevier Ltd. All rights reserved.

  3. Does the Role Checklist Measure Occupational Participation?

    Directory of Open Access Journals (Sweden)

    Tore Bonsaksen

    2015-07-01

    Full Text Available Background: Among the Model of Human Occupation (MOHO assessments, the Role Checklist is one of the most established. In spite of its widespread use, no studies have examined role examples and their association with the three embedded levels of doing, as established in the MOHO theory. Method: A cross-sectional survey of 293 respondents from the US, the UK, Japan, Switzerland, Sweden, and Norway produced 7,182 role examples. The respondents completed Part I of the Role Checklist and provided examples of each internalized role they performed. Responses were classified as occupational skill, occupational performance, or occupational participation. Results: Thirty-three percent of the examples were classified as examples of occupational participation, whereas 65% were classified as examples of occupational performance. Four roles linked mostly with occupational participation, another four roles linked mostly with occupational performance, and the two remaining roles were mixed between occupational participation and occupational performance. Discussion: The Role Checklist assesses a person’s involvement in internalized roles at the level of both occupational participation and occupational performance. There are differences among countries with regard to how roles are perceived and exemplified, and different roles relate differently to the occupational performance and occupational participation levels of doing. There are related implications for occupational therapists.

  4. Acute thermal stressor increases glucocorticoid response but minimizes testosterone and locomotor performance in the cane toad (Rhinella marina.

    Directory of Open Access Journals (Sweden)

    Edward J Narayan

    Full Text Available Climatic warming is a global problem and acute thermal stressor in particular could be considered as a major stressor for wildlife. Cane toads (Rhinella marina have expanded their range into warmer regions of Australia and they provide a suitable model species to study the sub-lethal impacts of thermal stressor on the endocrine physiology of amphibians. Presently, there is no information to show that exposure to an acute thermal stressor could initiate a physiological stress (glucocorticoid response and secondly, the possible effects on reproductive hormones and performance. Answering these questions is important for understanding the impacts of extreme temperature on amphibians. In this study, we experimented on cane toads from Queensland, Australia by acclimating them to mildly warm temperature (25°C and then exposing to acute temperature treatments of 30°, 35° or 40°C (hypothetical acute thermal stressors. We measured acute changes in the stress hormone corticosterone and the reproductive hormone testosterone using standard capture and handling protocol and quantified the metabolites of both hormones non-invasively using urinary enzyme-immunoassays. Furthermore, we measured performance trait (i.e. righting response score in the control acclimated and the three treatment groups. Corticosterone stress responses increased in all toads during exposure to an acute thermal stressor. Furthermore, exposure to a thermal stressor also decreased testosterone levels in all toads. The duration of the righting response (seconds was longer for toads that were exposed to 40°C than to 30°, 35° or 25°C. The increased corticosterone stress response with increased intensity of the acute thermal stressor suggests that the toads perceived this treatment as a stressor. Furthermore, the results also highlight a potential trade-off with performance and reproductive hormones. Ultimately, exposure acute thermal stressors due to climatic variability could impact

  5. Acute thermal stressor increases glucocorticoid response but minimizes testosterone and locomotor performance in the cane toad (Rhinella marina).

    Science.gov (United States)

    Narayan, Edward J; Hero, Jean-Marc

    2014-01-01

    Climatic warming is a global problem and acute thermal stressor in particular could be considered as a major stressor for wildlife. Cane toads (Rhinella marina) have expanded their range into warmer regions of Australia and they provide a suitable model species to study the sub-lethal impacts of thermal stressor on the endocrine physiology of amphibians. Presently, there is no information to show that exposure to an acute thermal stressor could initiate a physiological stress (glucocorticoid) response and secondly, the possible effects on reproductive hormones and performance. Answering these questions is important for understanding the impacts of extreme temperature on amphibians. In this study, we experimented on cane toads from Queensland, Australia by acclimating them to mildly warm temperature (25°C) and then exposing to acute temperature treatments of 30°, 35° or 40°C (hypothetical acute thermal stressors). We measured acute changes in the stress hormone corticosterone and the reproductive hormone testosterone using standard capture and handling protocol and quantified the metabolites of both hormones non-invasively using urinary enzyme-immunoassays. Furthermore, we measured performance trait (i.e. righting response score) in the control acclimated and the three treatment groups. Corticosterone stress responses increased in all toads during exposure to an acute thermal stressor. Furthermore, exposure to a thermal stressor also decreased testosterone levels in all toads. The duration of the righting response (seconds) was longer for toads that were exposed to 40°C than to 30°, 35° or 25°C. The increased corticosterone stress response with increased intensity of the acute thermal stressor suggests that the toads perceived this treatment as a stressor. Furthermore, the results also highlight a potential trade-off with performance and reproductive hormones. Ultimately, exposure acute thermal stressors due to climatic variability could impact amphibians at

  6. Biotic interactions modify multiple-stressor effects on juvenile brown trout in an experimental stream food web.

    Science.gov (United States)

    Bruder, Andreas; Salis, Romana K; Jones, Peter E; Matthaei, Christoph D

    2017-09-01

    Agricultural land use results in multiple stressors affecting stream ecosystems. Flow reduction due to water abstraction, elevated levels of nutrients and chemical contaminants are common agricultural stressors worldwide. Concurrently, stream ecosystems are also increasingly affected by climate change. Interactions among multiple co-occurring stressors result in biological responses that cannot be predicted from single-stressor effects (i.e. synergisms and antagonisms). At the ecosystem level, multiple-stressor effects can be further modified by biotic interactions (e.g. trophic interactions). We conducted a field experiment using 128 flow-through stream mesocosms to examine the individual and combined effects of water abstraction, nutrient enrichment and elevated levels of the nitrification inhibitor dicyandiamide (DCD) on survival, condition and gut content of juvenile brown trout and on benthic abundance of their invertebrate prey. Flow velocity reduction decreased fish survival (-12% compared to controls) and condition (-8% compared to initial condition), whereas effects of nutrient and DCD additions and interactions among these stressors were not significant. Negative effects of flow velocity reduction on fish survival and condition were consistent with effects on fish gut content (-25% compared to controls) and abundance of dominant invertebrate prey (-30% compared to controls), suggesting a negative metabolic balance driving fish mortality and condition decline, which was confirmed by structural equation modelling. Fish mortality under reduced flow velocity increased as maximal daily water temperatures approached the upper limit of their tolerance range, reflecting synergistic interactions between these stressors. Our study highlights the importance of indirect stressor effects such as those transferred through trophic interactions, which need to be considered when assessing and managing fish populations and stream food webs in multiple-stressor situations

  7. Towards inclusive occupational therapy: Introducing the CORE approach for inclusive and occupation-focused practice.

    Science.gov (United States)

    Pereira, Robert B

    2017-12-01

    Occupation is a human right and a social determinant of health. It is also taken for granted. Having access to, and participating in, occupation, is intricately linked to positive health and wellbeing. Despite theory and evidence to support the link between occupation, health and wellbeing, occupational therapists can struggle with applying an occupation focus in practice and knowing how to use occupational frameworks to enable occupation. The purpose of this paper is to introduce the Capabilities, Opportunities, Resources and Environments (CORE) approach for inclusive and occupation-focused practice. It provides occupational therapists with a means of operationalising occupational enablement and facilitating social inclusion. The CORE approach is introduced by linking its main ideas to Economist and Nobel Prize Laureate Amartya Sen's capabilities approach, as well as findings from the author's doctoral research into entrenched disadvantage and social inclusion. Practical questions guided by the CORE approach's acronym are given to explore how the approach can be utilised alongside other occupational models and frameworks to encourage strategies for effective enablement through occupation for social inclusion. As experts in enabling occupation, occupational therapists can use the CORE approach to design occupation-focused interventions and promote inclusive occupational therapy. © 2017 Occupational Therapy Australia.

  8. Modeling the potential area of occupancy at fine resolution may reduce uncertainty in species range estimates

    DEFF Research Database (Denmark)

    Jiménez-Alfaro, Borja; Draper, David; Nogues, David Bravo

    2012-01-01

    and maximum entropy modeling to assess whether different sampling (expert versus systematic surveys) may affect AOO estimates based on habitat suitability maps, and the differences between such measurements and traditional coarse-grid methods. Fine-scale models performed robustly and were not influenced...... by survey protocols, providing similar habitat suitability outputs with high spatial agreement. Model-based estimates of potential AOO were significantly smaller than AOO measures obtained from coarse-scale grids, even if the first were obtained from conservative thresholds based on the Minimal Predicted...... permit comparable measures among species. We conclude that estimates of AOO based on fine-resolution distribution models are more robust tools for risk assessment than traditional systems, allowing a better understanding of species ranges at habitat level....

  9. Software for occupational health and safety risk analysis based on a fuzzy model.

    Science.gov (United States)

    Stefanovic, Miladin; Tadic, Danijela; Djapan, Marko; Macuzic, Ivan

    2012-01-01

    Risk and safety management are very important issues in healthcare systems. Those are complex systems with many entities, hazards and uncertainties. In such an environment, it is very hard to introduce a system for evaluating and simulating significant hazards. In this paper, we analyzed different types of hazards in healthcare systems and we introduced a new fuzzy model for evaluating and ranking hazards. Finally, we presented a developed software solution, based on the suggested fuzzy model for evaluating and monitoring risk.

  10. Rating impacts in a multi-stressor world: a quantitative assessment of 50 stressors affecting the Great Lakes.

    Science.gov (United States)

    Smith, Sigrid D P; Mcintyre, Peter B; Halpern, Benjamin S; Cooke, Roger M; Marino, Adrienne L; Boyer, Gregory L; Buchsbaum, Andy; Burton, G A; Campbell, Linda M; Ciborowski, Jan J H; Doran, Patrick J; Infante, Dana M; Johnson, Lucinda B; Read, Jennifer G; Rose, Joan B; Rutherford, Edward S; Steinman, Alan D; Allan, J David

    2015-04-01

    Ecosystems often experience multiple environmental stressors simultaneously that can differ widely in their pathways and strengths of impact. Differences in the relative impact of environmental stressors can guide restoration and management prioritization, but few studies have empirically assessed a comprehensive suite of stressors acting on a given ecosystem. To fill this gap in the Laurentian Great Lakes, where considerable restoration investments are currently underway, we used expert elicitation via a detailed online survey to develop ratings of the relative impacts of 50 potential stressors. Highlighting the multiplicity of stressors in this system, experts assessed all 50 stressors as having some impact on ecosystem condition, but ratings differed greatly among stressors. Individual stressors related to invasive and nuisance species (e.g., dreissenid mussels and ballast invasion risk) and climate change were assessed as having the greatest potential impacts. These results mark a shift away from the longstanding emphasis on nonpoint phosphorus and persistent bioaccumulative toxic substances in the Great Lakes. Differences in impact ratings among lakes and ecosystem zones were weak, and experts exhibited surprisingly high levels of agreement on the relative impacts of most stressors. Our results provide a basin-wide, quantitative summary of expert opinion on the present-day influence of all major Great Lakes stressors. The resulting ratings can facilitate prioritizing stressors to achieve management objectives in a given location, as well as providing a baseline for future stressor impact assessments in the Great Lakes and elsewhere.

  11. Demonstration of a modelling-based multi-criteria decision analysis procedure for prioritisation of occupational risks from manufactured nanomaterials.

    Science.gov (United States)

    Hristozov, Danail; Zabeo, Alex; Alstrup Jensen, Keld; Gottardo, Stefania; Isigonis, Panagiotis; Maccalman, Laura; Critto, Andrea; Marcomini, Antonio

    2016-11-01

    Several tools to facilitate the risk assessment and management of manufactured nanomaterials (MN) have been developed. Most of them require input data on physicochemical properties, toxicity and scenario-specific exposure information. However, such data are yet not readily available, and tools that can handle data gaps in a structured way to ensure transparent risk analysis for industrial and regulatory decision making are needed. This paper proposes such a quantitative risk prioritisation tool, based on a multi-criteria decision analysis algorithm, which combines advanced exposure and dose-response modelling to calculate margins of exposure (MoE) for a number of MN in order to rank their occupational risks. We demonstrated the tool in a number of workplace exposure scenarios (ES) involving the production and handling of nanoscale titanium dioxide, zinc oxide (ZnO), silver and multi-walled carbon nanotubes. The results of this application demonstrated that bag/bin filling, manual un/loading and dumping of large amounts of dry powders led to high emissions, which resulted in high risk associated with these ES. The ZnO MN revealed considerable hazard potential in vivo, which significantly influenced the risk prioritisation results. In order to study how variations in the input data affect our results, we performed probabilistic Monte Carlo sensitivity/uncertainty analysis, which demonstrated that the performance of the proposed model is stable against changes in the exposure and hazard input variables.

  12. Shared and unshared exposure measurement error in occupational cohort studies and their effects on statistical inference in proportional hazards models

    Science.gov (United States)

    Laurier, Dominique; Rage, Estelle

    2018-01-01

    Exposure measurement error represents one of the most important sources of uncertainty in epidemiology. When exposure uncertainty is not or only poorly accounted for, it can lead to biased risk estimates and a distortion of the shape of the exposure-response relationship. In occupational cohort studies, the time-dependent nature of exposure and changes in the method of exposure assessment may create complex error structures. When a method of group-level exposure assessment is used, individual worker practices and the imprecision of the instrument used to measure the average exposure for a group of workers may give rise to errors that are shared between workers, within workers or both. In contrast to unshared measurement error, the effects of shared errors remain largely unknown. Moreover, exposure uncertainty and magnitude of exposure are typically highest for the earliest years of exposure. We conduct a simulation study based on exposure data of the French cohort of uranium miners to compare the effects of shared and unshared exposure uncertainty on risk estimation and on the shape of the exposure-response curve in proportional hazards models. Our results indicate that uncertainty components shared within workers cause more bias in risk estimation and a more severe attenuation of the exposure-response relationship than unshared exposure uncertainty or exposure uncertainty shared between individuals. These findings underline the importance of careful characterisation and modeling of exposure uncertainty in observational studies. PMID:29408862

  13. Radiography student perceptions of clinical stressors.

    Science.gov (United States)

    Mason, Starla L

    2006-01-01

    Technological change and the increasingly rapid pace of life in the United States and globally have contributed to increased levels of stress and burnout experienced by workers and their families. Although studies are available on the levels of workplace stress and burnout affecting radiographers, little to no research has been conducted to assess the stressors encountered by radiography students in the clinical environment. This study was designed to pinpoint the primary sources of stress for radiography students and to determine the most effective measures to alleviate the stress that students experience in the clinical environment. It also sought to identify the clinical activities and practices that enhance learning. A convenience sample of radiography students attending an Association of Collegiate Educators in Radiologic Technology meeting was surveyed. Students were asked to rank their greatest stressors in the clinical environment, the most desired qualities in a clinical instructor and clinical environment, and the clinical practices and activities that best enhance their learning. Descriptive statistics were used to report the results. Data were collected for 82 first-year and second-year students. Students identified 7 primary clinical stressors: fear of making a mistake/repeat, feeling unprepared/inexperienced, intimidation by staff and by instructors, difficult/critical patients, hurtful criticism, too much supervision and negative responses to questions/requests for help. Students indicated that more frequent feedback, availability of the clinical instructor and other staff, assurance that mistakes happen and the opportunity to make mistakes were clinical practices that eased stress. The majority of students cited hands-on learning and repetition as the clinical activities that most reinforced their learning. Summary Radiography students in this survey experience some of the same clinical stressors as radiographers and other allied health workers

  14. Multiple stressor effects in Chlamydomonas reinhardtii--toward understanding mechanisms of interaction between effects of ultraviolet radiation and chemical pollutants.

    Science.gov (United States)

    Korkaric, Muris; Behra, Renata; Fischer, Beat B; Junghans, Marion; Eggen, Rik I L

    2015-05-01

    The effects of chemical pollutants and environmental stressors, such as ultraviolet radiation (UVR), can interact when organisms are simultaneously exposed, resulting in higher (synergistic) or lower (antagonistic) multiple stressor effects than expected based on the effects of single stressors. Current understanding of interactive effects is limited due to a lack of mechanism-based multiple stressor studies. It has been hypothesized that effect interactions may generally occur if chemical and non-chemical stressors cause similar physiological effects in the organism. To test this hypothesis, we exposed the model green alga Chlamydomonas reinhardtii to combinations of UVR and single chemicals displaying modes of action (MOA) similar or dissimilar to the impact of UVR on photosynthesis. Stressor interactions were analyzed based on the independent action model. Effect interactions were found to depend on the MOA of the chemicals, and also on their concentrations, the exposure time and the measured endpoint. Indeed, only chemicals assumed to cause effects on photosynthesis similar to UVR showed interactions with UVR on photosynthetic yield: synergistic in case of Cd(II) and paraquat and antagonistic in case of diuron. No interaction on photosynthesis was observed for S-metolachlor, which acts dissimilarly to UVR. However, combined effects of S-metolachlor and UVR on algal reproduction were synergistic, highlighting the importance of considering additional MOA of UVR. Possible mechanisms of stressor effect interactions are discussed. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. When things don't add up: quantifying impacts of multiple stressors from individual metabolism to ecosystem processing.

    Science.gov (United States)

    Galic, Nika; Sullivan, Lauren L; Grimm, Volker; Forbes, Valery E

    2018-04-01

    Ecosystems are exposed to multiple stressors which can compromise functioning and service delivery. These stressors often co-occur and interact in different ways which are not yet fully understood. Here, we applied a population model representing a freshwater amphipod feeding on leaf litter in forested streams. We simulated impacts of hypothetical stressors, individually and in pairwise combinations that target the individuals' feeding, maintenance, growth and reproduction. Impacts were quantified by examining responses at three levels of biological organisation: individual-level body sizes and cumulative reproduction, population-level abundance and biomass and ecosystem-level leaf litter decomposition. Interactive effects of multiple stressors at the individual level were mostly antagonistic, that is, less negative than expected. Most population- and ecosystem-level responses to multiple stressors were stronger than expected from an additive model, that is, synergistic. Our results suggest that across levels of biological organisation responses to multiple stressors are rarely only additive. We suggest methods for efficiently quantifying impacts of multiple stressors at different levels of biological organisation. © 2018 John Wiley & Sons Ltd/CNRS.

  16. Cation interdependency in acute stressor states.

    Science.gov (United States)

    Khan, M Usman; Komolafe, Babatunde O; Weber, Karl T

    2013-05-01

    Acute stressor states are inextricably linked to neurohormonal activation which includes the adrenergic nervous system. Consequent elevations in circulating epinephrine and norepinephrine unmask an interdependency that exists between K+, Mg2+ and Ca2+. Catecholamines, for example, regulate the large number of Mg2+-dependent Na/K ATPase pumps present in skeletal muscle. A hyperadrenergic state accounts for a sudden translocation of K+ into muscle and rapid appearance of hypokalemia. In the myocardium, catecholamines promote Mg2+ efflux from cardiomyocytes, whereas intracellular Ca2+ influx and overloading account for the induction of oxidative stress and necrosis of these cells with leakage of their contents, including troponins. Accordingly, acute stressor states can be accompanied by nonischemic elevations in serum troponins, together with the concordant appearance of hypokalemia, hypomagnesemia and ionized hypocalcemia, causing a delay in myocardial repolarization and electrocardiographic QTc prolongation raising the propensity for arrhythmias, including atrial fibrillation and polymorphic ventricular tachycardia. In this review, we focus on the interdependency between K+, Mg2+ and Ca2+ which are clinically relevant to acute stressor states.

  17. Multiple stressor effects in Chlamydomonas reinhardtii – Toward understanding mechanisms of interaction between effects of ultraviolet radiation and chemical pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Korkaric, Muris [Eawag, Swiss Federal Institute of Aquatic Science and Technology, Department of Environmental Toxicology, 8600, Duebendorf (Switzerland); ETH Zürich, Institute of Biogeochemistry and Pollutant Dynamics, 8092 Zürich (Switzerland); Behra, Renata; Fischer, Beat B. [Eawag, Swiss Federal Institute of Aquatic Science and Technology, Department of Environmental Toxicology, 8600, Duebendorf (Switzerland); Junghans, Marion [Swiss Center for Applied Ecotoxicology Eawag-EPFL, 8600, Duebendorf (Switzerland); Eggen, Rik I.L., E-mail: rik.eggen@eawag.ch [Eawag, Swiss Federal Institute of Aquatic Science and Technology, Department of Environmental Toxicology, 8600, Duebendorf (Switzerland); ETH Zürich, Institute of Biogeochemistry and Pollutant Dynamics, 8092 Zürich (Switzerland)

    2015-05-15

    Highlights: • Systematic study of multiple stressor effects of UVR and chemicals in C. reinhardtii. • UVR and chemicals did not act independently on algal photosynthesis and reproduction. • Multiple stressor effects of UVR and chemicals depended on chemical MOA. • Synergistic effect interactions not limited to oxidative stress inducing chemicals. • Multiple MOAs of UVR may limit applicability of current prediction models. - Abstract: The effects of chemical pollutants and environmental stressors, such as ultraviolet radiation (UVR), can interact when organisms are simultaneously exposed, resulting in higher (synergistic) or lower (antagonistic) multiple stressor effects than expected based on the effects of single stressors. Current understanding of interactive effects is limited due to a lack of mechanism-based multiple stressor studies. It has been hypothesized that effect interactions may generally occur if chemical and non-chemical stressors cause similar physiological effects in the organism. To test this hypothesis, we exposed the model green alga Chlamydomonas reinhardtii to combinations of UVR and single chemicals displaying modes of action (MOA) similar or dissimilar to the impact of UVR on photosynthesis. Stressor interactions were analyzed based on the independent action model. Effect interactions were found to depend on the MOA of the chemicals, and also on their concentrations, the exposure time and the measured endpoint. Indeed, only chemicals assumed to cause effects on photosynthesis similar to UVR showed interactions with UVR on photosynthetic yield: synergistic in case of Cd(II) and paraquat and antagonistic in case of diuron. No interaction on photosynthesis was observed for S-metolachlor, which acts dissimilarly to UVR. However, combined effects of S-metolachlor and UVR on algal reproduction were synergistic, highlighting the importance of considering additional MOA of UVR. Possible mechanisms of stressor effect interactions are

  18. Multiple stressor effects in Chlamydomonas reinhardtii – Toward understanding mechanisms of interaction between effects of ultraviolet radiation and chemical pollutants

    International Nuclear Information System (INIS)

    Korkaric, Muris; Behra, Renata; Fischer, Beat B.; Junghans, Marion; Eggen, Rik I.L.

    2015-01-01

    Highlights: • Systematic study of multiple stressor effects of UVR and chemicals in C. reinhardtii. • UVR and chemicals did not act independently on algal photosynthesis and reproduction. • Multiple stressor effects of UVR and chemicals depended on chemical MOA. • Synergistic effect interactions not limited to oxidative stress inducing chemicals. • Multiple MOAs of UVR may limit applicability of current prediction models. - Abstract: The effects of chemical pollutants and environmental stressors, such as ultraviolet radiation (UVR), can interact when organisms are simultaneously exposed, resulting in higher (synergistic) or lower (antagonistic) multiple stressor effects than expected based on the effects of single stressors. Current understanding of interactive effects is limited due to a lack of mechanism-based multiple stressor studies. It has been hypothesized that effect interactions may generally occur if chemical and non-chemical stressors cause similar physiological effects in the organism. To test this hypothesis, we exposed the model green alga Chlamydomonas reinhardtii to combinations of UVR and single chemicals displaying modes of action (MOA) similar or dissimilar to the impact of UVR on photosynthesis. Stressor interactions were analyzed based on the independent action model. Effect interactions were found to depend on the MOA of the chemicals, and also on their concentrations, the exposure time and the measured endpoint. Indeed, only chemicals assumed to cause effects on photosynthesis similar to UVR showed interactions with UVR on photosynthetic yield: synergistic in case of Cd(II) and paraquat and antagonistic in case of diuron. No interaction on photosynthesis was observed for S-metolachlor, which acts dissimilarly to UVR. However, combined effects of S-metolachlor and UVR on algal reproduction were synergistic, highlighting the importance of considering additional MOA of UVR. Possible mechanisms of stressor effect interactions are

  19. Assessing Risks to Wildlife Populations from Multiple Stressors: Overview of the Problem and Research Needs.

    Directory of Open Access Journals (Sweden)

    Wayne R. Munns, Jr.

    2006-06-01

    Full Text Available Wildlife populations are experiencing increasing pressure from human-induced changes in the landscape. Stressors including agricultural and urban land use, introduced invasive and exotic species, nutrient enrichment, direct human disturbance, and toxic chemicals directly or indirectly influence the quality and quantity of habitat used by terrestrial and aquatic wildlife. Governmental agencies such as the U.S. Environmental Protection Agency are required to assess risks to wildlife populations, in its broadest definition, that result from exposure to these stressors, yet considerable uncertainty exists with respect to how such assessments should be conducted. This uncertainty is compounded by questions concerning the interactive effects of co-occurring stressors, appropriate spatial scales of analysis, extrapolation of response data among species and from organisms to populations, and imperfect knowledge and use of limited data sets. Further, different risk problems require varying degrees of sophistication, methodological refinement, and data quality. These issues suggest a number of research needs to improve methods for wildlife risk assessments, including continued development of population dynamics models to evaluate the effects of multiple stressors at varying spatial scales, methods for extrapolating across endpoints and species with reasonable confidence, stressor-response relations and methods for combining them in predictive and diagnostic assessments, and accessible data sets describing the ecology of terrestrial and aquatic species. Case study application of models and methods for assessing wildlife risk will help to demonstrate their strengths and limitations for solving particular risk problems.

  20. Combining public participatory surveillance and occupancy modelling to predict the distributional response of Ixodes scapularis to climate change.

    Science.gov (United States)

    Lieske, David J; Lloyd, Vett K

    2018-03-01

    Ixodes scapularis, a known vector of Borrelia burgdorferi sensu stricto (Bbss), is undergoing range expansion in many parts of Canada. The province of New Brunswick, which borders jurisdictions with established populations of I. scapularis, constitutes a range expansion zone for this species. To better understand the current and potential future distribution of this tick under climate change projections, this study applied occupancy modelling to distributional records of adult ticks that successfully overwintered, obtained through passive surveillance. This study indicates that I. scapularis occurs throughout the southern-most portion of the province, in close proximity to coastlines and major waterways. Milder winter conditions, as indicated by the number of degree days model with a predictive accuracy of 0.845 (range: 0.828-0.893). Both RCP 4.5 and RCP 8.5 climate projections predict that a significant proportion of the province (roughly a quarter to a third) will be highly suitable for I. scapularis by the 2080s. Comparison with cases of canine infection show good spatial agreement with baseline model predictions, but the presence of canine Borrelia infections beyond the climate envelope, defined by the highest probabilities of tick occurrence, suggest the presence of Bbss-carrying ticks distributed by long-range dispersal events. This research demonstrates that predictive statistical modelling of multi-year surveillance information is an efficient way to identify areas where I. scapularis is most likely to occur, and can be used to guide subsequent active sampling efforts in order to better understand fine scale species distributional patterns. Copyright © 2018 The Authors. Published by Elsevier GmbH.. All rights reserved.

  1. Knowledge-Based Energy Damage Model for Evaluating Industrialised Building Systems (IBS Occupational Health and Safety (OHS Risk

    Directory of Open Access Journals (Sweden)

    Abas Nor Haslinda

    2016-01-01

    Full Text Available Malaysia’s construction industry has been long considered hazardous, owing to its poor health and safety record. It is proposed that one of the ways to improve safety and health in the construction industry is through the implementation of ‘off-site’ systems, commonly termed ‘industrialised building systems (IBS’ in Malaysia. This is deemed safer based on the risk concept of reduced exposure, brought about by the reduction in onsite workers; however, no method yet exists for determining the relative safety of various construction methods, including IBS. This study presents a comparative evaluation of the occupational health and safety (OHS risk presented by different construction approaches, namely IBS and traditional methods. The evaluation involved developing a model based on the concept of ‘argumentation theory’, which helps construction designers integrate the management of OHS risk into the design process. In addition, an ‘energy damage model’ was used as an underpinning framework. Development of the model was achieved through three phases, namely Phase I – knowledge acquisitaion, Phase II – argument trees mapping, and Phase III – validation of the model. The research revealed that different approaches/methods of construction projects carried a different level of energy damage, depending on how the activities were carried out. A study of the way in which the risks change from one construction process to another shows that there is a difference in the profile of OHS risk between IBS construction and traditional methods.Therefore, whether the option is an IBS or traditional approach, the fundamental idea of the model is to motivate construction designers or decision-makers to address safety in the design process and encourage them to examine carefully the probable OHS risk variables surrounding an action, thus preventing accidents in construction.

  2. Occupation as a risk factor for hypertensive disorders of pregnancy.

    Science.gov (United States)

    Bilhartz, Terry D; Bilhartz, Patty

    2013-02-01

    Hypertensive disorders of pregnancy (HDP) are leading causes of morbidity and mortality and have been rising in incidence. Little is known about the effects of worker classifications on HDP. This large-scale study examines associations between occupational classifications and HDP. We examined 385,537 Texas Electronic Registrar Birth Registration 2005 birth certificates. Maternal occupations were coded using the Standard Occupational Classification (SOC). Crude and adjusted risks for HDP among working women within occupational groupings were analyzed and compared with risks of nonemployed women. The risk of developing HDP varies across SOC occupational classifications. After controlling for known confounders, women employed in business, management, and the legal and social services, teaching, counseling, and healthcare professions are at higher risk for developing HDP than women employed in support industries, such as food preparation, housekeeping, cosmetic and personal care services, or nonemployed women. Women employed in computer, engineering, architectural, and scientific occupations also carry greater risks, although these increased risks do not affect women of normal weight. Worker classification is an independent risk factor for HDP. Additional work must be done to examine the complex interactions among individual maternal genetics, biology, and physical and mental abilities and how they affect adverse health outcomes. Examining job stressors may shed light on these occupational variations and their potential HDP associations. Strategies to mitigate job stressors in the workplace should be considered.

  3. Using occupancy and population models to assess habitat conservation opportunities for an isolated carnivore population

    Science.gov (United States)

    Wayne Spencer; Heather Rustigian-Romsos; James Strittholt; Robert Scheller; William Zielinski; Richard Truex

    2011-01-01

    An isolated population of the fisher (Martes pennanti) in the southern Sierra Nevada, California, is threatened by small size and habitat alteration from wildfires, fuels management, and other factors. We assessed the population’s status and conservation options for its habitat using a spatially explicit population model coupled with a...

  4. The Effect of Occupational Stress on Health and Illness: A Model.

    Science.gov (United States)

    Taylor, William L.; Cangemi, Joseph P.

    1988-01-01

    Examines brief history of stress research and concludes that psychological factors can affect job satisfaction, work adjustment, work attitudes, and overall well-being in the work environment. Establishes relationship between mental and physiological functioning disturbances. Presents model relating effect of stress on health and illness. (Author)

  5. Using satellite and airborne LiDAR to model woodpecker habitat occupancy at the landscape scale

    Science.gov (United States)

    Lee A. Vierling; Kerri T. Vierling; Patrick Adam; Andrew T. Hudak

    2013-01-01

    Incorporating vertical vegetation structure into models of animal distributions can improve understanding of the patterns and processes governing habitat selection. LiDAR can provide such structural information, but these data are typically collected via aircraft and thus are limited in spatial extent. Our objective was to explore the utility of satellite-based LiDAR...

  6. The effects of working conditions and financial state as job stressors : A comparison of the chronic job stressors and job event stressors of two companies

    OpenAIRE

    Kosugi, Shoutaro; Otsuka, Yasumasa

    2000-01-01

    This study examined the effects of working conditions and the financial state as chronic job stressors and job event stressors. In study 1, the Job Stress Scale was applied to a total of 6,312 employees in an industrial research institute and a construction company to measure chronic job stressors. In study 2, 1,423 employees of these companies filled out the Job Events Checklist to measure job event stressors. Result: Employees in the industrial research institute had more chronic job stress...

  7. An etiologic prediction model incorporating biomarkers to predict the bladder cancer risk associated with occupational exposure to aromatic amines: a pilot study

    OpenAIRE

    Mastrangelo, Giuseppe; Carta, Angela; Arici, Cecilia; Pavanello, Sofia; Porru, Stefano

    2017-01-01

    Background No etiological prediction model incorporating biomarkers is available to predict bladder cancer risk associated with occupational exposure to aromatic amines. Methods Cases were 199 bladder cancer patients. Clinical, laboratory and genetic data were predictors in logistic regression models (full and short) in which the dependent variable was 1 for 15 patients with aromatic amines related bladder cancer and 0 otherwise. The receiver operating characteristics approach was adopted; th...

  8. Cancer Survivors’ Responses to Daily Stressors: Implications for Quality of Life

    Science.gov (United States)

    Costanzo, Erin S.; Stawski, Robert S.; Ryff, Carol D.; Coe, Christopher L.; Almeida, David M.

    2012-01-01

    Objective This study examined cancer survivors’ experience of and responses to challenges and stressors associated with every-day living. The impact of daily stressors on quality of life concerns and cortisol patterns was also investigated. Design Participants were 111 cancer survivors who participated in a national telephone diary study of daily experiences (NSDE). Their responses were compared with those of 111 sociodemographically-matched participants with no cancer history using a multilevel modeling approach. Main Outcome Measures Over an 8-day period, participants completed a daily inventory of the occurrence and impact of stressful events, affect, and physical symptoms. Salivary cortisol was sampled 4 times per day, and indices of awakening response (CAR), diurnal slope, and overall output (AUC) were examined. Results Cancer survivors experienced similar numbers and types of stressful events as the comparison group. While appraisals were largely comparable, cancer survivors showed a modest tendency to perceive stressors as more severe and disruptive, particularly those involving interpersonal tensions. The occurrence of stressors was associated with increased negative affect, decreased positive affect, and increased physical symptoms, but little change in cortisol. Relative to the comparison group, cancer survivors showed less pronounced changes in positive affect and cortisol output when stressors occurred, but a greater increase in negative affect in response to interpersonal conflicts. Conclusions Findings indicate that cancer survivors show a resilient ability to respond to day-to-day stressors and challenges. However, daily stressors can have a significant impact on survivors’ mood and physical symptoms and therefore may be an important intervention target. PMID:22268712

  9. Daily Stressor Reactivity during Adolescence: The Buffering Role of Parental Warmth

    Science.gov (United States)

    Lippold, Melissa; Davis, Kelly D.; McHale, Susan M.; Buxton, Orfeu; Almeida, David M.

    2016-01-01

    Objective This study examined youth stressor reactivity in the form of links between daily stressors and adolescents’ negative affect, physical health symptoms, and cortisol patterns. We also tested whether youth gender and parental warmth moderated these linkages. Method Participants were the children of employees in the Information Technology division of a large company (N = 132, mean age = 13.39 years, 55% female). Youth completed daily diary telephone interviews on 8 consecutive evenings and provided saliva samples at 4 time points over 4 days to assess daily stressors and youth physiological and affective functioning. Parental warmth was assessed during in-home interviews. Multi-level modeling was used to account for interdependencies in the data. Result