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Sample records for stress moderation model

  1. Perceived stress and resilience in Alzheimer's disease caregivers: testing moderation and mediation models of social support.

    Science.gov (United States)

    Wilks, Scott E; Croom, Beth

    2008-05-01

    The study examined whether social support functioned as a protective, resilience factor among Alzheimer's disease (AD) caregivers. Moderation and mediation models were used to test social support amid stress and resilience. A cross-sectional analysis of self-reported data was conducted. Measures of demographics, perceived stress, family support, friend support, overall social support, and resilience were administered to caregiver attendees (N=229) of two AD caregiver conferences. Hierarchical regression analysis showed the compounded impact of predictors on resilience. Odds ratios generated probability of high resilience given high stress and social supports. Social support moderation and mediation were tested via distinct series of regression equations. Path analyses illustrated effects on the models for significant moderation and/or mediation. Stress negatively influenced and accounted for most variation in resilience. Social support positively influenced resilience, and caregivers with high family support had the highest probability of elevated resilience. Moderation was observed among all support factors. No social support fulfilled the complete mediation criteria. Evidence of social support as a protective, moderating factor yields implications for health care practitioners who deliver services to assist AD caregivers, particularly the promotion of identification and utilization of supportive familial and peer relations.

  2. Workplace ostracism And workplace behaviors: A moderated mediation model of perceived stress and psychological empowerment.

    Science.gov (United States)

    Chung, Yang Woon

    2018-05-01

    Workplace ostracism research has examined numerous underlying mechanisms to understand the link between workplace ostracism and behavioral outcomes. Ostracism has been suggested to be an interpersonal stressor; however, research has not investigated workplace ostracism from a stress perspective. Therefore, the study investigated the mediating effect of perceived stress for the relationships between workplace ostracism and helping behavior, voicing behavior, and task performance. The study also investigated the moderating effect of psychological empowerment for the relationships between perceived stress and behavioral outcomes. The study design was a three-wave self-reported questionnaire. The study sampled 225 full-time employees in South Korea and regression analyses with bootstrapping were conducted to test the moderated mediation models. The bootstrapped 95% CI around the indirect effects did not contain zero; therefore, perceived stress mediated the relationship between workplace ostracism and helping behavior (-.06), voicing behavior (-.07), and task performance (-.07). Further, the moderated mediation analyses found perceived stress mediated the relationships between workplace ostracism and behavioral outcomes only when individuals perceived low levels of psychological empowerment. The findings suggest that workplace ostracism is a stressor and psychological empowerment can mitigate the negative effects of ostracism on behavioral outcomes.

  3. Discrimination, acculturation, acculturative stress, and Latino psychological distress: a moderated mediational model.

    Science.gov (United States)

    Torres, Lucas; Driscoll, Mark W; Voell, Maria

    2012-01-01

    Prior research has found that perceived discrimination is associated with adverse mental health outcomes among Latinos. However, the process by which this relationship occurs remains an understudied area. The present study investigated the role of acculturative stress in underlying the relationship between perceived discrimination and Latino psychological distress. Also examined was the ability of acculturation to serve as a moderator between perceived discrimination and acculturative stress. Among a sample of Latino adults (N = 669), moderated mediational analyses revealed that acculturative stress mediated the perceived discrimination-psychological distress relationship, and that the link between perceived discrimination and acculturative stress was moderated by Anglo behavioral orientation but not Latino behavioral orientation. The findings are discussed within a stress and coping perspective that identifies the psychological consequences associated with perceived discrimination and acculturative stress.

  4. Depression amongst Chinese Adolescents in Hong Kong: An Evaluation of a Stress Moderation Model

    Science.gov (United States)

    Ng, Catalina S. M.; Hurry, Jane

    2011-01-01

    Stress has an established association with depression. However, not all adolescents experiencing stressors become depressed and it is helpful to identify potential resilience factors. The current study tests a theoretical extension of a stress-diathesis model of depression in a Chinese context, with stress, coping, family relationships, and…

  5. High-risk diagnosis, social stress, and parent-child relationships: A moderation model.

    Science.gov (United States)

    Bentley, Eryn; Millman, Zachary B; Thompson, Elizabeth; Demro, Caroline; Kline, Emily; Pitts, Steven C; DeVylder, Jordan E; Smith, Melissa Edmondson; Reeves, Gloria; Schiffman, Jason

    2016-07-01

    Stress is related to symptom severity among youth at clinical high-risk (CHR) for psychosis, although this relation may be influenced by protective factors. We explored whether the association of CHR diagnosis with social stress is moderated by the quality of parent-child relationships in a sample of 96 (36 CHR; 60 help-seeking controls) adolescents and young adults receiving mental health services. We examined self-reported social stress and parent-child relationships as measured by the Behavior Assessment System for Children, Second Edition (BASC-2), and determined CHR status from the clinician-administered Structured Interview for Psychosis-Risk Syndrome (SIPS). The social stress subscale, part of the clinical domain of the BASC-2, assesses feelings of stress and tension in personal relationships and the relations with parents subscale, part of the adaptive domain of the BASC-2, assesses perceptions of importance in family and quality of parent-child relationship. There was a modest direct relation between risk diagnosis and social stress. Among those at CHR, however, there was a significant relation between parent-child relationships and social stress (b=-0.73, t[92]=-3.77, psocial stress for those at risk for psychosis. Findings provide additional evidence to suggest that interventions that simultaneously target both social stress and parent-child relationships might be relevant for adolescents and young adults at clinical high-risk for psychosis. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Relationships Between Stress, Negative Emotions, Resilience, and Smoking: Testing a Moderated Mediation Model.

    Science.gov (United States)

    Wang, Yan; Chen, Xinguang; Gong, Jie; Yan, Yaqiong

    2016-01-01

    More effective tobacco prevention and cessation programs require in-depth understanding of the mechanism by which multiple factors interact with each other to affect smoking behaviors. Stress has long been recognized as a risk factor for smoking. However, the underlying mediation and moderation mechanisms are far from clear. The purpose of this study was to examine the role of negative emotions in mediating the link between stress and smoking and whether this indirect link was modified by resilience. Survey data were collected using audio computer-assisted self-interview (ACASI) from a large random sample of urban residents (n = 1249, mean age = 35.1, 45.3% male) in Wuhan, China. Perceived stress, negative emotions (anxiety, depression), resilience were measured with reliable instruments also validated in China. Self-reported smoking was validated with exhaled carbon monoxide. Mediation analysis indicated that two negative emotions fully mediated the link between stress and intensity of smoking (assessed by number of cigarettes smoked per day, effect =.082 for anxiety and.083 for depression) and nicotine dependence (assessed by DSM-IV standard, effect =.134 for anxiety and.207 for depression). Moderated mediation analysis demonstrated that the mediation effects of negative emotions were negatively associated with resilience. Results suggest resilience interacts with stress and negative emotions to affect the risk of tobacco use and nicotine dependence among Chinese adults. Further research with longitudinal data is needed to verify the findings of this study and to estimate the effect size of resilience in tobacco intervention and cessation programs.

  7. Posttraumatic Stress, Family Functioning, and Externalizing in Adolescents Exposed to Violence: A Moderated Mediation Model.

    Science.gov (United States)

    Deane, Kyle; Richards, Maryse; Mozley, Michaela; Scott, Darrick; Rice, Catherine; Garbarino, James

    2016-09-02

    Exposure to community violence disproportionately impacts low-income, minority youth and is associated with posttraumatic stress symptoms and maladaptive adjustment. This study investigates whether posttraumatic stress mediates the relation between exposure to community violence and externalizing symptoms and the moderating role of family cohesion and daily family support in buffering these effects on later externalizing. Low-income, African American 7th-grade students (M age = 12.57 years; N = 254) from high-crime neighborhoods participated in a 2-year longitudinal study measuring the effects of community violence exposure. The students completed questionnaires administered by research staff over 5 consecutive days for each year of the study. Family cohesion and daily family support exhibited a significant buffering effect for several outcomes. Posttraumatic stress significantly mediated the effect of witnessing community violence on subsequent aggression. The strength of these indirect effects depended on level of family cohesion. The findings provide evidence in support of interventions provided at both individual and family levels. Mental health providers working with this population should be aware of the intertwined nature of exposure to community violence, posttraumatic stress, and subsequent maladaptive outcomes.

  8. The Effect of Short Moderate Stress on the Midbrain CRF System in a Macaque Model of Functional Hypothalamic Amenorrhea

    Science.gov (United States)

    Bethea, Cynthia L; Phu, Kenny; Reddy, Arubala P; Cameron, Judy L

    2014-01-01

    Objective To study the effect of moderate stress on CRF components in the serotonergic midbrain region in a monkey model of FHA. Design After characterization of stress sensitivity, monkeys were moved to a novel room and given 20% less chow for 5 days prior to euthanasia. Setting University of Pittsburgh nonhuman primate facility. Animals Female cynomolgus macaques (Macaca fascicularis) characterized as highly stress resilient (HSR, n=5), medium stress resilient (MSR, N=4) or stress sensitive (SS, n=4). Intervention 5 days of diet in a novel room with unfamiliar conspecifics. Main Outcome Measures Density of CRF axons in the serotonergic dorsal raphe nucleus; the number of UCN1 cells; the density of UCN1 axons; the expression of CRF-R1 and CRF-R2 in the dorsal raphe nucleus. Results CRF innervation was higher in HSR than SS animals; UCN1 cell number was higher in HSR than SS animals and UCN1 axon bouton density was not different, all opposite of non-stressed animals. CRF-R1 was not different between the sensitivity groups, but CRF-R2 was higher in HSR than SS animals. The relative expression of CRF-R1 and R2 was similar to non-stressed animals. Conclusions HSR animals respond to stress with an increase in CRF delivery to serotonin neurons. With stress, UCN1 transport decreases in HSR animals. CRF receptor expression was similar with or without stress. These changes may contribute to resilience in HSR animals. PMID:23849846

  9. Male Asian international students' perceived racial discrimination, masculine identity, and subjective masculinity stress: a moderated mediation model.

    Science.gov (United States)

    Wong, Y Joel; Tsai, Pei-Chun; Liu, Tao; Zhu, Qingqing; Wei, Meifen

    2014-10-01

    This study examined male Asian international college students' perceptions of racial discrimination, subjective masculinity stress, centrality of masculine identity, and psychological distress by testing a moderated mediation model. Participants were 160 male Asian international college students from 2 large public universities. Participants' perceived racial discrimination was positively related to their subjective masculinity stress only at high (but not low) levels of masculine identity centrality. Additionally, subjective masculinity stress was positively related to psychological distress, although this association was stronger among those who reported high levels of masculine identity centrality. The authors also detected a moderated mediation effect in which subjective masculinity stress mediated the relationship between perceived racial discrimination and psychological distress only at high (but not low) levels of masculine identity centrality. These findings contribute to the counseling psychology literature by highlighting the connections between race- and gender-related stressors as well as the relevance of masculine identity to an understanding of men's mental health. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  10. Moderated Online Social Therapy: A Model for Reducing Stress in Carers of Young People Diagnosed with Mental Health Disorders.

    Science.gov (United States)

    Gleeson, John; Lederman, Reeva; Koval, Peter; Wadley, Greg; Bendall, Sarah; Cotton, Sue; Herrman, Helen; Crisp, Kingsley; Alvarez-Jimenez, Mario

    2017-01-01

    Family members caring for a young person diagnosed with the onset of mental health problems face heightened stress, depression, and social isolation. Despite evidence for the effectiveness of family based interventions, sustaining access to specialist family interventions is a major challenge. The availability of the Internet provides possibilities to expand and sustain access to evidence-based psychoeducation and personal support for family members. In this paper we describe the therapeutic model and the components of our purpose-built moderated online social therapy (MOST) program for families. We outline the background to its development, beginning with our face-to-face EPISODE II family intervention, which informed our selection of therapeutic content, and the integration of recent developments in positive psychology. Our online interventions for carers integrate online therapy, online social networking, peer and expert support, and online social problem solving which has been designed to reduce stress in carers. The initial version of our application entitled Meridian was shown to be safe, acceptable, and feasible in a feasibility study of carers of youth diagnosed with depression and anxiety. There was a significant reduction in self-reported levels of stress in caregivers and change in stress was significantly correlated with use of the system. We have subsequently launched a cluster RCT for caregivers with a relative diagnosed with first-episode psychosis. Our intervention has the potential to improve access to effective specialist support for families facing the onset of serious mental health problems in their young relative.

  11. A Model of Oxidative Stress Management: Moderation of Carbohydrate Metabolizing Enzymes in SOD1-Null Drosophila melanogaster

    Science.gov (United States)

    Bernard, Kristine E.; Parkes, Tony L.; Merritt, Thomas J. S.

    2011-01-01

    The response to oxidative stress involves numerous genes and mutations in these genes often manifest in pleiotropic ways that presumably reflect perturbations in ROS-mediated physiology. The Drosophila melanogaster SOD1-null allele (cSODn108) is proposed to result in oxidative stress by preventing superoxide breakdown. In SOD1-null flies, oxidative stress management is thought to be reliant on the glutathione-dependent antioxidants that utilize NADPH to cycle between reduced and oxidized form. Previous studies suggest that SOD1-null Drosophila rely on lipid catabolism for energy rather than carbohydrate metabolism. We tested these connections by comparing the activity of carbohydrate metabolizing enzymes, lipid and triglyceride concentration, and steady state NADPH:NADP+ in SOD1-null and control transgenic rescue flies. We find a negative shift in the activity of carbohydrate metabolizing enzymes in SOD1-nulls and the NADP+-reducing enzymes were found to have significantly lower activity than the other enzymes assayed. Little evidence for the catabolism of lipids as preferential energy source was found, as the concentration of lipids and triglycerides were not significantly lower in SOD1-nulls compared with controls. Using a starvation assay to impact lipids and triglycerides, we found that lipids were indeed depleted in both genotypes when under starvation stress, suggesting that oxidative damage was not preventing the catabolism of lipids in SOD1-null flies. Remarkably, SOD1-nulls were also found to be relatively resistant to starvation. Age profiles of enzyme activity, triglyceride and lipid concentration indicates that the trends observed are consistent over the average lifespan of the SOD1-nulls. Based on our results, we propose a model of physiological response in which organisms under oxidative stress limit the production of ROS through the down-regulation of carbohydrate metabolism in order to moderate the products exiting the electron transport chain. PMID

  12. Stress and alcohol use in rural Chinese residents: A moderated mediation model examining the roles of resilience and negative emotions.

    Science.gov (United States)

    Wang, Yan; Chen, Xinguang

    2015-10-01

    Little research has been done on alcohol use and dependence among rural residents in China, a sub-population that might be under increased stress due to the rapid modernization and urbanization processes. We aimed to assess rural residents' levels of stress, negative emotions, resilience, alcohol use/dependence and the complex relationships among them. Survey data from a large random sample (n=1145, mean age=35.9, SD=7.7, 50.7% male) of rural residents in Wuhan, China were collected using Audio Computer-Assisted Self-Interview. The sample had high prevalence of frequently perceived stress (47%) and high prevalence of ever (54.4%), past 30-day (40.4%), and binge drinking (13.8%). Approximately 11% met the criterion for intermediate to severe alcohol dependence. Mediation analysis indicated that the association between perceived stress (predictor) and alcohol dependence (outcome) was fully mediated by anxiety (indirect effect=.203, pstress and two negative emotions (mediators) was significantly modified by resilience (moderator); an integrative moderated mediation analysis indicated that the indirect effect from stress to alcohol dependence through negative emotions was also moderated by resilience. Negative emotions play a key role in bridging stress and alcohol dependence, while resilience significantly buffers the impact of stress on depression, reducing the risk of alcohol dependence. Resilience training may be an effective component for alcohol intervention in rural China. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  13. Accuracy of finite-element models for the stress analysis of multiple-holed moderator blocks

    International Nuclear Information System (INIS)

    Smith, P.D.; Sullivan, R.M.; Lewis, A.C.; Yu, H.J.

    1981-01-01

    Two steps have been taken to quantify and improve the accuracy in the analysis. First, the limitations of various approximation techniques have been studied with the aid of smaller benchmark problems containing fewer holes. Second, a new family of computer programs has been developed for handling such large problems. This paper describes the accuracy studies and the benchmark problems. A review is given of some proposed modeling techniques including local mesh refinement, homogenization, a special-purpose finite element, and substructuring. Some limitations of these approaches are discussed. The new finite element programs and the features that contribute to their efficiency are discussed. These include a standard architecture for out-of-core data processing and an equation solver that operates on a peripheral array processor. The central conclusions of the paper are: (1) modeling approximation methods such as local mesh refinement and homogenization tend to be unreliable, and they should be justified by a fine mesh benchmark analysis; and (2) finite element codes are now available that can achieve accurate solutions at a reasonable cost, and there is no longer a need to employ modeling approximations in the two-dimensional analysis of HTGR fuel elements. 10 figures

  14. The effect of short moderate stress on the midbrain corticotropin-releasing factor system in a macaque model of functional hypothalamic amenorrhea.

    Science.gov (United States)

    Bethea, Cynthia L; Phu, Kenny; Reddy, Arubala P; Cameron, Judy L

    2013-10-01

    To study the effect of moderate stress on corticotropin-releasing factor (CRF) components in the serotonergic midbrain region in a monkey model of functional hypothalamic amenorrhea. After characterization of stress sensitivity, monkeys were moved to a novel room and given 20% less chow for 5 days before euthanasia. Primate research center. Female cynomolgus macaques (Macaca fascicularis) characterized as highly stress resilient (HSR, n = 5), medium stress resilient (n = 4), or stress sensitive (SS, n = 4). Five days of diet in a novel room with unfamiliar conspecifics. Density of CRF axons in the serotonergic dorsal raphe nucleus; the number of urocortin 1 (UCN1) cells; the density of UCN1 axons; the expression of CRF receptor 1 (CRF-R1) and CRF-R2 in the dorsal raphe nucleus. The CRF innervation was higher in HSR than in SS animals; UCN1 cell number was higher in HSR than in SS animals and UCN1 axon bouton density was not different; all opposite of nonstressed animals. The CRF-R1 was not different between the sensitivity groups, but CRF-R2 was higher in HSR than in SS animals. The relative expression of CRF-R1 and CRF-R2 was similar to nonstressed animals. The HSR animals respond to stress with an increase in CRF delivery to serotonin neurons. With stress, UCN1 transport decreases in HSR animals. The CRF receptor expression was similar with or without stress. These changes may contribute to resilience in HSR animals. Copyright © 2013 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  15. Role of stressful life events, avoidant coping styles, and neuroticism in online game addiction among college students: a moderated mediation model

    Directory of Open Access Journals (Sweden)

    Li Huanhuan

    2016-11-01

    Full Text Available Online game addiction (OGA is becoming a significant problem worldwide. The aim of this study was to explore the incidence of OGA and the roles of stressful life events, avoidant coping styles (ACSs, and neuroticism in OGA. A total of 651 Chinese college students were selected by random cluster sampling. Subjects completed the Chinese version of Young’s eight-item Internet Addiction Scale (CIAS, Online Game Cognition Addiction Scale (OGCAS, Revised Eysenck Personality Questionnaire Short Scale in Chinese (EPQ-RSC, Chinese College-student Stress Questionnaire (CCSQ, and Coping Style Questionnaire (CSQ. Structural equation modeling (SEM was used to explore the interactive effects of stressful life events, ACSs, and neuroticism on OGA. Of the 651 participants in the sample, 31 (4.8% were identified as addicts. The incidence of OGA was two times higher for males than females. The addicts had markedly higher scores on the neuroticism subscale of the EPQ-RSC than non-addicts. Compared to non-addicts, addicts were more apt to use ACSs. Having an avoidant coping strategy mediated the effect of stressful life events on OGA. Furthermore, neuroticism moderated the indirect effect of stressful life events on OGA via ACSs. Applications of these findings to etiological research and clinical treatment programs are discussed.

  16. Role of Stressful Life Events, Avoidant Coping Styles, and Neuroticism in Online Game Addiction among College Students: A Moderated Mediation Model.

    Science.gov (United States)

    Li, Huanhuan; Zou, Yingmin; Wang, Jiaqi; Yang, Xuelin

    2016-01-01

    Online game addiction (OGA) is becoming a significant problem worldwide. The aim of this study was to explore the incidence of OGA and the roles of stressful life events, avoidant coping styles (ACSs), and neuroticism in OGA. A total of 651 Chinese college students were selected by random cluster sampling. Subjects completed the Chinese version of Young's eight-item Internet Addiction Scale (CIAS), Online Game Cognition Addiction Scale (OGCAS), Revised Eysenck Personality Questionnaire Short Scale in Chinese (EPQ-RSC), Chinese College-student Stress Questionnaire, and Coping Style Questionnaire. Structural equation modeling (SEM) was used to explore the interactive effects of stressful life events, ACSs, and neuroticism on OGA. Of the 651 participants in the sample, 31 (4.8%) were identified as addicts. The incidence of OGA was two times higher for males than females. The addicts had markedly higher scores on the neuroticism subscale of the EPQ-RSC than non-addicts. Compared to non-addicts, addicts were more apt to use ACSs. Having an avoidant coping strategy mediated the effect of stressful life events on OGA. Furthermore, neuroticism moderated the indirect effect of stressful life events on OGA via ACSs. Applications of these findings to etiological research and clinical treatment programs are discussed.

  17. Role of Stressful Life Events, Avoidant Coping Styles, and Neuroticism in Online Game Addiction among College Students: A Moderated Mediation Model

    Science.gov (United States)

    Li, Huanhuan; Zou, Yingmin; Wang, Jiaqi; Yang, Xuelin

    2016-01-01

    Online game addiction (OGA) is becoming a significant problem worldwide. The aim of this study was to explore the incidence of OGA and the roles of stressful life events, avoidant coping styles (ACSs), and neuroticism in OGA. A total of 651 Chinese college students were selected by random cluster sampling. Subjects completed the Chinese version of Young’s eight-item Internet Addiction Scale (CIAS), Online Game Cognition Addiction Scale (OGCAS), Revised Eysenck Personality Questionnaire Short Scale in Chinese (EPQ-RSC), Chinese College-student Stress Questionnaire, and Coping Style Questionnaire. Structural equation modeling (SEM) was used to explore the interactive effects of stressful life events, ACSs, and neuroticism on OGA. Of the 651 participants in the sample, 31 (4.8%) were identified as addicts. The incidence of OGA was two times higher for males than females. The addicts had markedly higher scores on the neuroticism subscale of the EPQ-RSC than non-addicts. Compared to non-addicts, addicts were more apt to use ACSs. Having an avoidant coping strategy mediated the effect of stressful life events on OGA. Furthermore, neuroticism moderated the indirect effect of stressful life events on OGA via ACSs. Applications of these findings to etiological research and clinical treatment programs are discussed. PMID:27920734

  18. Effects of high-intensity interval versus continuous moderate-intensity aerobic exercise on apoptosis, oxidative stress and metabolism of the infarcted myocardium in a rat model.

    Science.gov (United States)

    Lu, Kai; Wang, Li; Wang, Changying; Yang, Yuan; Hu, Dayi; Ding, Rongjing

    2015-08-01

    The optimal aerobic exercise training (AET) protocol for patients following myocardial infarction (MI) has remained under debate. The present study therefore aimed to compare the effects of continuous moderate-intensity training (CMT) and high-intensity interval training (HIT) on cardiac functional recovery, and to investigate the potential associated mechanisms in a post-MI rat model. Female Sprague Dawley rats (8-10 weeks old) undergoing MI or sham surgery were subsequently submitted to CMT or HIT, or kept sedentary for eight weeks. Prior to and following AET, echocardiographic parameters and exercise capacity of the rats were measured. Western blotting was used to evaluate the levels of apoptosis and associated signaling pathway protein expression. The concentrations of biomarkers of oxidative stress were also determined by ELISA assay. Messenger (m)RNA levels and activity of the key enzymes for glycolysis and fatty acid oxidation, as well as the rate of adenosine triphosphate (ATP) synthesis, were also measured. Compared with the MI group, exercise capacity and cardiac function were significantly improved following AET, particularly following HIT. Left ventricular ejection fraction and fraction shortening were further improved in the MI-HIT group in comparison to that of the MI-CMT group. The two forms of AET almost equally attenuated apoptosis of the post-infarction myocardium. CMT and HIT also alleviated oxidative stress by decreasing the concentration of malondialdehyde and increasing the concentration of superoxide dismutase and glutathione peroxidase (GPx). In particular, HIT induced a greater increase in the concentration of GPx than that of CMT. AET, and HIT in particular, significantly increased the levels of mRNA and the maximal activity of phosphofructokinase-1 and carnitine palmitoyl transferase-1, as well as the maximal ratio of ATP synthesis. In addition, compared with the MI group, the expression of signaling proteins PI3K, Akt, p38mapk and AMPK

  19. Cognitive control moderates parenting stress effects on children's diurnal cortisol

    OpenAIRE

    Raffington, Laurel; Schmiedek, Florian; Heim, Christine; Shing, Yee Lee

    2018-01-01

    This study investigated associations between parenting stress in parents and self-reported stress in children with children's diurnal cortisol secretion and whether these associations are moderated by known stress-regulating capacities, namely child cognitive control. Salivary cortisol concentrations were assessed from awakening to evening on two weekend days from 53 6-to-7-year-old children. Children completed a cognitive control task and a self-report stress questionnaire with an experiment...

  20. The Role of Rumination and Stressful Life Events in the Relationship between the Qi Stagnation Constitution and Depression in Women: A Moderated Mediation Model

    Science.gov (United States)

    Liu, Qiaosheng

    2017-01-01

    The qi stagnation constitution is associated with depression in traditional Chinese medicine. It is unclear how rumination and stressful life events affect the relationship between the qi stagnation constitution and depression. The Qi Stagnation Constitution Scale, Ruminative Response Scale, Center for Epidemiologic Studies Depression Scale, and Adolescent Self-Rating Life Events Checklist were used to assess this association in 1200 female college students. The results revealed that the qi stagnation constitution was positively associated with depression. Furthermore, rumination was a partial mediator of the relationship between the qi stagnation constitution and depression. In addition, stressful life events moderated the direct effect and mediating effect of the qi stagnation constitution on depression. These findings indicate that rumination and stressful life events may affect the relationship between the qi stagnation constitution and depression in women. PMID:28757889

  1. The Role of Rumination and Stressful Life Events in the Relationship between the Qi Stagnation Constitution and Depression in Women: A Moderated Mediation Model

    Directory of Open Access Journals (Sweden)

    Mingfan Liu

    2017-01-01

    Full Text Available The qi stagnation constitution is associated with depression in traditional Chinese medicine. It is unclear how rumination and stressful life events affect the relationship between the qi stagnation constitution and depression. The Qi Stagnation Constitution Scale, Ruminative Response Scale, Center for Epidemiologic Studies Depression Scale, and Adolescent Self-Rating Life Events Checklist were used to assess this association in 1200 female college students. The results revealed that the qi stagnation constitution was positively associated with depression. Furthermore, rumination was a partial mediator of the relationship between the qi stagnation constitution and depression. In addition, stressful life events moderated the direct effect and mediating effect of the qi stagnation constitution on depression. These findings indicate that rumination and stressful life events may affect the relationship between the qi stagnation constitution and depression in women.

  2. Role Stress Revisited: Job Structuring Antecedents, Work Outcomes, and Moderating Effects of Locus of Control

    Science.gov (United States)

    Conley, Sharon; You, Sukkyung

    2014-01-01

    A previous study examined role stress in relation to work outcomes; in this study, we added job structuring antecedents to a model of role stress and examined the moderating effects of locus of control. Structural equation modeling was used to assess the plausibility of our conceptual model, which specified hypothesized linkages among teachers'…

  3. Resilience amid Academic Stress: The Moderating Impact of Social Support among Social Work Students

    Directory of Open Access Journals (Sweden)

    Scott E. Wilks

    2008-12-01

    Full Text Available Purpose: The purpose of this study was to examine the relationship between academic stress and perceived resilience among social work students, and to identify social support as a protective factor of resilience on this relationship. A conceptual model of moderation was used to test the role of social support as protective. Methods: The sample consisted of 314 social work students (BSW=144; MSW=170 from three accredited schools/programs in the southern United States. Voluntary survey data were collected on demographics and constructs of academic stress, family support, friend support, and resilience. Hierarchical regression analysis was conducted to show the composite impact of demographic and model factors on the resilience outcome. Moderation was tested using a traditional regression series as guidelines of moderation with continuous variables. Path analyses illustrated main effects and moderation in the study’s conceptual model. Results: The sample reported moderate levels of academic stress and social support, and a fairly high level of resilience. Academic stress negatively related to social support and resilience. Social support positively influenced resilience. Academic stress accounted for the most variation in resilience scores. Friend support significantly moderated the negative relationship between academic stress and resilience. Conclusion: The current study demonstrated the likelihood that friend support plays a protective role with resilience amid an environment of academic stress. Implications for social work faculty and internship agency practitioners are discussed.

  4. The involvement of oxidative stress in the mechanisms of damaging cadmium action in bone tissue: A study in a rat model of moderate and relatively high human exposure

    International Nuclear Information System (INIS)

    Brzoska, Malgorzata M.; Rogalska, Joanna; Kupraszewicz, Elzbieta

    2011-01-01

    It was investigated whether cadmium (Cd) may induce oxidative stress in the bone tissue in vivo and in this way contribute to skeleton damage. Total antioxidative status (TAS), antioxidative enzymes (glutathione peroxidase, superoxide dismutase, catalase), total oxidative status (TOS), hydrogen peroxide (H 2 O 2 ), lipid peroxides (LPO), total thiol groups (TSH) and protein carbonyl groups (PC) as well as Cd in the bone tissue at the distal femoral epiphysis and femoral diaphysis of the male rats that received drinking water containing 0, 5, or 50 mg Cd/l for 6 months were measured. Cd, depending on the level of exposure and bone location, decreased the bone antioxidative capacity and enhanced its oxidative status resulting in oxidative stress and oxidative protein and/or lipid modification. The treatment with 5 and 50 mg Cd/l decreased TAS and activities of antioxidative enzymes as well as increased TOS and concentrations of H 2 O 2 and PC at the distal femur. Moreover, at the higher exposure, the concentration of LPO increased and that of TSH decreased. The Cd-induced changes in the oxidative/antioxidative balance of the femoral diaphysis, abundant in cortical bone, were less advanced than at the distal femur, where trabecular bone predominates. The results provide evidence that, even moderate, exposure to Cd induces oxidative stress and oxidative modifications in the bone tissue. Numerous correlations noted between the indices of oxidative/antioxidative bone status, and Cd accumulation in the bone tissue as well as indices of bone turnover and bone mineral status, recently reported by us (Toxicology 2007, 237, 89-103) in these rats, allow for the hypothesis that oxidative stress is involved in the mechanisms of damaging Cd action in the skeleton. The paper is the first report from an in vivo study indicating that Cd may affect bone tissue through disorders in its oxidative/antioxidative balance resulting in oxidative stress.

  5. Stress and Quality of Life in Breast Cancer Recurrence: Moderation or Mediation of Coping?

    Science.gov (United States)

    Yang, Hae-Chung; Brothers, Brittany M.; Andersen, Barbara L.

    2008-01-01

    Background/Purpose Diagnosis with breast cancer recurrence often brings high levels of stress. Successful coping to alleviate stress could improve patients' quality of life (QoL). The intervening role coping plays between stress and QoL may depend on the types of stress encountered and the types of coping strategies used. The present study investigates the longitudinal relationships between stress, coping, and mental health QoL. Methods Breast cancer patients recently diagnosed with recurrence (N=65) were assessed shortly after the diagnosis and 4 months later. Four moderation and four mediation models were tested using hierarchical multiple regressions and path analyses. In the models, either traumatic stress or symptom-related stress at recurrence diagnosis was a predictor of mental health QoL at follow-up. Both engagement and disengagement coping strategies were tested as moderators or mediators between stress and QoL. Results Engagement coping moderated the effect of symptom stress on mental health QoL, whereas disengagement coping mediated the effects of both traumatic stress and symptom stress on mental health QoL. Conclusion The findings imply that interventions teaching engagement coping strategies would be important for patients experiencing high symptom stress, while discouraging the use of disengagement coping strategies would be important for all patients. PMID:18347897

  6. Evaluating personality as a moderator of the association between life events stress and cardiovascular reactivity to acute stress.

    Science.gov (United States)

    Gallagher, Stephen; O'Riordan, Adam; McMahon, Grace; Creaven, Ann-Marie

    2018-04-01

    The present study investigated the possible interaction between life events stress and personality in predicting cardiovascular stress responses. Participants (N = 184) completed psychometric measures of life event stress and personality styles and had cardiovascular responses monitored during a standardised stress testing protocol. In adjusted models, the observed blunted association between life event stress and SBP and DBP was moderated by openness; this was more evident at -1SD below the mean openness value. Further, the association between life event stress and TPR vascular resistance was found to be moderated by conscientiousness. In particular, we found conscientiousness at both the mean and 1SD above the mean buffered against the negative impact of life stress on TPR reactivity. The findings are discussed in relation to theory and future directions. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Examining the Effects of Jyoti Meditation on Stress and the Moderating Role of Emotional Intelligence

    Science.gov (United States)

    Gutierrez, Daniel; Conley, Abigail H.; Young, Mark

    2016-01-01

    The authors examined whether Jyoti meditation (JM), a spiritually based meditation (Singh, 2012), influenced student counselors' (N = 60) level of stress and emotional intelligence (EI). Results from a randomized controlled trial and growth curve analysis provided a multilevel model in which JM reduced stress and EI moderated the effect.

  8. Insulin resistance and its possible personal stress moderators

    Directory of Open Access Journals (Sweden)

    Oleg G. Motovilin

    2017-08-01

    Full Text Available Background. Recently, insulin resistance (IR has been actively investigated by experts in various fields. Here we aim to study the effect of stress on the development of IR. Objective. To study the associations between IR and personal stress moderators (self-attitude, locus of control and coping strategies as well as the related performance lifestyles. Methods. The study included 63 patients (16 men; mean age, 48.2 ± 11.7 years. Of these participants, 26 were diagnosed with type 2 diabetes mellitus, 10 with impaired glucose tolerance, 6 with impaired fasting glucose and 21 with normal glucose tolerance. The levels of HbA1c and IR ratio were determined using HOMA. Well-known psychological assessment questionnaires were used to assess the effect of personal stress moderators. Results. There was a significant relationship between IR and personal stress moderators. A positive self-attitude was associated with a lower risk of IR (p < 0.05, which can be explained by a decrease in the risk of developing stress. Assertive coping strategies were most pronounced in subjects with a low level of IR (p < 0.05. Personal characteristics also determined an individual’s lifestyle, which may have an impact on the increase in IR. There was an association between high levels of IR and unhealthy alimentary preferences (p < 0.05. Such preferences were also associated with personal characteristics, such as external locus of control, less positive self-attitude and passive coping strategies (p < 0.05. People with high IR rarely engage in a regular physical activity; there was a direct correlation between the frequency of physical activity and assertive coping strategies (p < 0.01. Married participants had high levels of IR (p < 0.05. Conclusion. There were significant relationships between IR and personal stress moderators, such as self-attitude and coping strategies. Besides the direct effects on stress levels, personality traits may also indirectly increase the

  9. Stress vulnerability and the effects of moderate daily stress on sleep polysomnography and subjective sleepiness.

    Science.gov (United States)

    Petersen, Helena; Kecklund, Göran; D'Onofrio, Paolo; Nilsson, Jens; Åkerstedt, Torbjörn

    2013-02-01

    The purpose of this study was to investigate if and how sleep physiology is affected by naturally occurring high work stress and identify individual differences in the response of sleep to stress. Probable upcoming stress levels were estimated through weekly web questionnaire ratings. Based on the modified FIRST-scale (Ford insomnia response to stress) participants were grouped into high (n = 9) or low (n = 19) sensitivity to stress related sleep disturbances (Drake et al., 2004). Sleep was recorded in 28 teachers with polysomnography, sleep diaries and actigraphs during one high stress and one low stress condition in the participants home. EEG showed a decrease in sleep efficiency during the high stress condition. Significant interactions between group and condition were seen for REM sleep, arousals and stage transitions. The sensitive group had an increase in arousals and stage transitions during the high stress condition and a decrease in REM, whereas the opposite was seen in the resilient group. Diary ratings during the high stress condition showed higher bedtime stress and lower ratings on the awakening index (insufficient sleep and difficulties awakening). Ratings also showed lower cognitive function and preoccupation with work thoughts in the evening. KSS ratings of sleepiness increased during stress for the sensitive group. Saliva samples of cortisol showed no effect of stress. It was concluded that moderate daily stress is associated with a moderate negative effect on sleep sleep efficiency and fragmentation. A slightly stronger effect was seen in the sensitive group. © 2012 European Sleep Research Society.

  10. Perceived stress and dietary choices: The moderating role of stress management.

    Science.gov (United States)

    Errisuriz, Vanessa L; Pasch, Keryn E; Perry, Cheryl L

    2016-08-01

    Many college students exhibit unhealthy eating behaviors, consuming large quantities of high-fat foods and few fruits and vegetables. Perceived stress has been linked to daily dietary choices among college students; however, this work has been conducted among predominantly white, female populations. The role of perceived stress management in moderating this relationship is unclear. This study investigated the relationship between perceived stress and dietary choices among a diverse sample of male and female college freshmen and assessed whether perceived ability to manage stress moderated this relationship. 613 students from a large, public university completed an online survey which assessed past week consumption of various foods and beverages (e.g. soda, fast food, fruits, vegetables), as well as perceived stress and ability to manage stress. Hierarchical linear regression examined the association between perceived stress and past week dietary choices, and the moderating effect of perceived ability to manage stress, controlling for demographic variables. Perceived stress was positively associated with past week soda, coffee, energy drink, salty snack, frozen food, and fast food consumption (pmoderated the relationship between stress and sweet snack consumption. Individuals who reported low ability to manage stress consumed greater amounts. Findings indicate greater stress is associated with poor dietary choices among college freshmen. The relationship between stress and sweet snack consumption was exacerbated among those who reported low ability to manage stress. It may be important for college nutrition education programs to focus on the relationship between stress and diet and promote effective stress management techniques. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Effect of perceived stress on depression of Chinese "Ant Tribe" and the moderating role of dispositional optimism.

    Science.gov (United States)

    Liu, Bo; Pu, Jun; Hou, Hanpo

    2015-05-08

    This study examines the moderating role of dispositional optimism on the relationship between perceived stress and depression of the Chinese "Ant Tribe." A total of 427 participants from an Ant Tribe community completed the measures of perceived stress, optimism, and depression. The structural equation modeling (SEM) analysis showed that dispositional optimism moderated the association between perceived stress and depression. The Ant Tribe with high perceived stress reported higher scores in depression than those with low perceived stress at low dispositional optimism level. However, the impact of perceived stress on depression was insignificant in the high dispositional optimism group. © The Author(s) 2015.

  12. Exploring the Role of the Built and Social Neighborhood Environment in Moderating Stress and Health

    Science.gov (United States)

    Yang, Tse-Chuan

    2014-01-01

    Background Health researchers have explored how different aspects of neighborhood characteristics contribute to health and well-being, but current understanding of built environment factors is limited. Purpose This study explores whether the association between stress and health varies by residential neighborhood, and if yes, whether built and social neighborhood environment characteristics act as moderators. Methods This study uses multilevel modeling and variables derived from geospatial data to explore the role of neighborhood environment in moderating the association of stress with health. Individual-level data (N=4,093) were drawn from residents of 45 neighborhoods within Philadelphia County, PA, collected as part of the 2006 Philadelphia Health Management Corporation's Household Health Survey. Results We find that the negative influence of high stress varied by neighborhood, that residential stability and affluence (social characteristics) attenuated the association of high stress with health, and that the presence of hazardous waste facilities (built environment characteristics) moderated health by enhancing the association with stress. Conclusions Our findings suggest that neighborhood environment has both direct and moderating associations with health, after adjusting for individual characteristics. The use of geospatial data could broaden the scope of stress–health research and advance knowledge by untangling the intertwined relationship between built and social environments, stress, and health. In particular, future studies should integrate built environment characteristics in health-related research; these characteristics are modifiable and can facilitate health promotion policies. PMID:20300905

  13. A numerical study of internal brick stresses in AGR moderator bricks

    Energy Technology Data Exchange (ETDEWEB)

    McNally, K., E-mail: kevin.mcnally@hsl.gsi.gov.uk [Health and Safety Laboratory, Harpur Hill, Buxton, Derbyshire SK17 9JN (United Kingdom); Fahad, M. [NGRG, School of MACE, University of Manchester, Manchester M13 9PL (United Kingdom); Tan, E.; Warren, N. [Health and Safety Laboratory, Harpur Hill, Buxton, Derbyshire SK17 9JN (United Kingdom); Hall, G.N.; Marsden, B.J. [NGRG, School of MACE, University of Manchester, Manchester M13 9PL (United Kingdom)

    2016-12-01

    Highlights: • A methodology for studying the uncertainty in internal brick stresses was developed. • A computationally efficient methodology based upon a surrogate model was utilised. • Uncertainty in material relationships, particularly those related to secondary creep was the dominant source of uncertainty. - Abstract: Physically-based models are often used to model changes in geometry and the associated stress fields of graphite moderator bricks within an advanced gas-cooled reactor (AGR). These models require inputs that describe the loading conditions, and coded relationships describing the behaviour of material properties. Material relationships are primarily based upon data obtained from inspection campaigns at operating reactors. However, the data from trepanning campaigns do not provide information on some of the key relationships and parameters that affect the internal stresses generated within the moderator bricks. In this work we explore how uncertain material property relationships affect the internal brick stresses in early- and late-life. We describe two computer experiments designed to study early- and late-life brick stresses and report the results from global sensitivity analysis of the models. The work makes use of an emulator, a surrogate for the FE model, in order to make the sensitivity analyses computationally feasible.

  14. A numerical study of internal brick stresses in AGR moderator bricks

    International Nuclear Information System (INIS)

    McNally, K.; Fahad, M.; Tan, E.; Warren, N.; Hall, G.N.; Marsden, B.J.

    2016-01-01

    Highlights: • A methodology for studying the uncertainty in internal brick stresses was developed. • A computationally efficient methodology based upon a surrogate model was utilised. • Uncertainty in material relationships, particularly those related to secondary creep was the dominant source of uncertainty. - Abstract: Physically-based models are often used to model changes in geometry and the associated stress fields of graphite moderator bricks within an advanced gas-cooled reactor (AGR). These models require inputs that describe the loading conditions, and coded relationships describing the behaviour of material properties. Material relationships are primarily based upon data obtained from inspection campaigns at operating reactors. However, the data from trepanning campaigns do not provide information on some of the key relationships and parameters that affect the internal stresses generated within the moderator bricks. In this work we explore how uncertain material property relationships affect the internal brick stresses in early- and late-life. We describe two computer experiments designed to study early- and late-life brick stresses and report the results from global sensitivity analysis of the models. The work makes use of an emulator, a surrogate for the FE model, in order to make the sensitivity analyses computationally feasible.

  15. Stress moderates the relationship between problematic Internet use by parents and problematic Internet use by adolescents.

    Science.gov (United States)

    Lam, Lawrence T; Wong, Emmy M Y

    2015-03-01

    Based on the theoretical framework of Problem Behavior and Stress Reduction theories for problematic Internet use (PIU), this study aimed to investigate the relationship between parental PIU and the PIU among adolescents taking into consideration the stress levels of young people. This was a population-based parent and adolescent dyad health survey utilizing a random sampling technique. PIU for both parents and adolescents was measured by the Internet addiction test designed by Young. The stress level of adolescents was assessed using the stress subscale of the Depression Anxiety Stress Scale (DASS). Data were analyzed using logistic regression modeling techniques with adjustment for potential confounding factors with analysis on the modification effect of stress levels on the relationship between parent and adolescent PIU. Of the total 1,098 parent and adolescent dyads with usable information, 263 adolescents (24.0%) and 62 parents (5.7%) could be classified as moderate and severe problematic users of the Internet. About 14% (n = 157) of adolescents could be classified with moderate-to-severe stress. Regression analysis results suggested a significant interaction between parental PIU and adolescents' stress levels on adolescent PIU. Stratified regression analyses by stress level resulted in a significant parent and adolescent PIU relationship in the low stress group (odds ratio, 3.18; 95% confidence interval 1.65-6.14). However, the association between parent and adolescent PIU in the high stress group became insignificant. There was a significant parent and adolescent PIU relationship; however, this relationship is differentially affected by the stress status of the adolescent. The direct implication of the results is that parental Internet use should also be assessed and included as part of the treatment regime for adolescents. Copyright © 2015 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  16. Association of stress coping strategies with Internet addiction in college students: The moderating effect of depression.

    Science.gov (United States)

    Chou, Wei-Po; Ko, Chih-Hung; Kaufman, Erin A; Crowell, Sheila E; Hsiao, Ray C; Wang, Peng-Wei; Lin, Jin-Jia; Yen, Cheng-Fang

    2015-10-01

    This study examined the association between stress-related coping strategies and Internet addiction and the moderating effect of depression in a sample of Taiwanese college students. A total of 500 college students (238 men and 262 women) participated in this study. Internet addiction was assessed using the Chen Internet Addiction Scale. Participants' stress coping strategies and depressive symptoms were measured using the Coping Orientation to Problems Experienced and the Beck Depression Inventory-II, respectively. We used t and chi-square tests to examine differences in demographic characteristics, depression, and stress coping strategies between participants with and without Internet addiction. Significant variables were used in a logistic regression model to examine the association between stress coping strategies and Internet addiction and the moderating effect of depression on the association. Results indicated that use of restraint coping was negatively associated with Internet addiction (odds ratio [OR]=0.886, 95% confidence interval [CI]: 0.802-0.977), whereas denial (OR=1.177, 95% CI: 1.029-1.346) and mental disengagement (OR=2.673, 95% CI: 1.499-4.767) were positively associated with Internet addiction. Depression had a moderating effect on the association between denial and Internet addiction (OR=0.701, 95% CI: 0.530-0.927). Stress coping strategies and depression are important factors to evaluate when developing intervention programs targeting college undergraduate students with Internet addiction. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Is the Relationship Between Marital Adjustment and Parenting Stress Mediated or Moderated by Parenting Alliance?

    Directory of Open Access Journals (Sweden)

    Elena Camisasca

    2014-05-01

    Full Text Available The purpose of this study was to explore the mediating and moderating effects of parenting alliance on the relationship between marital adjustment, as represented by the dimensions dyadic consensus, dyadic satisfaction, dyadic cohesion, and affectional expression, and maternal and paternal stress. Self-report data were gathered from 236 Italian families (236 mothers: M = 40.9; SD = 4.4 and 236 fathers: M = 42.9; SD = 4.8 of children aged 6–11 years (M = 8.6; SD = 1.7. A set of regression analyses were conducted to examine whether parenting alliance mediates or moderates the relationship between marital adjustment and parenting stress. Regression analyses were consistent with a model of coparenting as a mediator but not as a moderator of the relationship between marital adjustment and parenting stress. In the case of mothers, parenting alliance mediates the relationships between two dimensions of marital adjustment (dyadic consensus and dyadic cohesion on parenting stress; in the case of fathers, parenting alliance serves as a mediator of the relationship between the marital adjustment (in terms of dyadic satisfaction and parenting stress. Implications for future research and interventions are discussed.

  18. Keep your eyes open: dispositional vigilance moderates the relationship between operational police stress and stress symptoms.

    Science.gov (United States)

    Kubiak, Jeanette; Krick, Annika; Egloff, Boris

    2017-09-01

    Vigilant coping is characterized by a deep processing of threat-related information. In many cases, vigilant coping increases stress symptoms, whereas avoidant coping decreases negative affect. However, vigilance may be beneficial when stress-eliciting situations involve a risk of injury or escalation as is usually the case in police operations. We investigated the roles of vigilance and cognitive avoidance in police operations in a cross-sectional survey. The participants were 137 students (104 men, M age  = 28.54, SD = 8.04) from the Federal University of Applied Administrative Sciences; 76 of them were already police officers (work experience: M = 12.59 years), and 61 were police officer candidates who had completed a 3- to 6-month police internship. Participants completed a paper-and-pencil survey and reported their operational stress, dispositional vigilance and cognitive avoidance in police operations, and stress symptoms. We found that vigilance was negatively associated with stress symptoms and moderated the relationship between operational stress and stress symptoms. Cognitive avoidance, on the other hand, just missed the level of statistical significance in our test of whether it was positively associated with stress symptoms. Our findings demonstrate that vigilance may protect against the negative consequences of stress in police operations.

  19. The Moderating Effect of Impulsivity on the Relationship between Stressful Life Events and Depression among College Women

    Science.gov (United States)

    Clarke, Dave

    2012-01-01

    Based on the transpersonal model of stress, the purpose of the study was to investigate the moderating effect of impulsivity on the relationship between stressful life events (SLE) and depression among first year university women. Impulsivity consists of tendencies towards lack of premeditation, lack of perseverance, urgency and sensation seeking.…

  20. Resilience amid Academic Stress: The Moderating Impact of Social Support among Social Work Students

    OpenAIRE

    Scott E. Wilks

    2008-01-01

    Purpose: The purpose of this study was to examine the relationship between academic stress and perceived resilience among social work students, and to identify social support as a protective factor of resilience on this relationship. A conceptual model of moderation was used to test the role of social support as protective. Methods: The sample consisted of 314 social work students (BSW=144; MSW=170) from three accredited schools/programs in the southern United States. Voluntary survey data we...

  1. Healthy eating at different risk levels for job stress: testing a moderated mediation.

    Science.gov (United States)

    Fodor, Daniel P; Antoni, Conny H; Wiedemann, Amelie U; Burkert, Silke

    2014-04-01

    Health behavior, like fruit and vegetable consumption (FVC), is affected by unfavorable job conditions. However, there is little research to date that combines job stress models and health-behavior change models. This longitudinal study examined the contribution of risk factors associated with job stress to the intention-planning-FVC relationship. In the context of the Health Action Process Approach, action planning (when-where-how plans) and coping planning (plans to overcome anticipated barriers) have been shown to be successful mediators in the translation of health-related intentions into action. Risk factors for job stress are operationalized as the interaction of job demands and job resources in line with the Job Demands-Resources (JD-R) model. Two hundred seventy-two employees (mean age 41.2 years, 73.9% female) from different jobs completed measures of intention at baseline (t1), action planning and coping planning 2 weeks later (t2), and FVC another 2 weeks later (t3). Job demands and job resources were assessed at t1 and t2. A moderated mediation analysis indicated that risk factors for job stress moderate the translation of intention into action planning (B = -0.23, p < .05) and coping planning (B = -0.14, p < .05). No moderation effect of the planning-FVC relationship by risk factors for job stress was found. However, coping planning directly predicted FVC (B = 0.36, p < .001). Findings suggest that employees intending to eat healthily use action planning and coping planning when job demands exceed job resources. For increasing FVC, coping planning appears most beneficial.

  2. Strength through adversity: Moderate lifetime stress exposure is associated with psychological resilience in breast cancer survivors.

    Science.gov (United States)

    Dooley, Larissa N; Slavich, George M; Moreno, Patricia I; Bower, Julienne E

    2017-12-01

    Stress research typically emphasizes the toxic effects of stress, but recent evidence has suggested that stress exposure, in moderation, can facilitate resilience. To test whether moderate stress exposure promotes psychological resilience to cancer, we examined the relationship between lifetime stress exposure prior to cancer diagnosis and postdiagnosis psychological functioning among 122 breast cancer survivors. Lifetime acute and chronic stress was assessed using an interview-based measure, and psychological functioning was assessed using measures of cancer-related intrusive thoughts and positive and negative affect. Results indicated that acute stress exposure was associated with cancer-related intrusive thoughts in a quadratic fashion (p = .016), such that participants with moderate acute stress reported fewer intrusive thoughts compared to those with low or high acute stress. Similarly, a quadratic relationship emerged between acute stress exposure and positive affect (p = .009), such that individuals with moderate acute stress reported the highest levels of positive affect. In contrast, acute and chronic stress were related to negative affect in a positive, linear fashion (ps < .05). In conclusion, moderate stress exposure was associated with indicators of psychological resilience among breast cancer survivors, supporting stress exposure as a key factor influencing adjustment to breast cancer and providing evidence for stress-induced resilience in a novel population. Copyright © 2017 John Wiley & Sons, Ltd.

  3. Problem-solving skills and perceived stress among undergraduate students: The moderating role of hardiness.

    Science.gov (United States)

    Abdollahi, Abbas; Abu Talib, Mansor; Carlbring, Per; Harvey, Richard; Yaacob, Siti Nor; Ismail, Zanariah

    2016-06-01

    This study was designed to examine the relationships between problem-solving skills, hardiness, and perceived stress and to test the moderating role of hardiness in the relationship between problem-solving skills and perceived stress among 500 undergraduates from Malaysian public universities. The analyses showed that undergraduates with poor problem-solving confidence, external personal control of emotion, and approach-avoidance style were more likely to report perceived stress. Hardiness moderated the relationships between problem-solving skills and perceived stress. These findings reinforce the importance of moderating role of hardiness as an influencing factor that explains how problem-solving skills affect perceived stress among undergraduates.

  4. STRESS, RELATIONSHIP SATISFACTION, AND HEALTH AMONG AFRICAN AMERICAN WOMEN: GENETIC MODERATION OF EFFECTS

    Science.gov (United States)

    Lei, Man-Kit; Beach, Steven R. H.; Simons, Ronald L.; Barr, Ashley B.; Cutrona, Carolyn E.; Philibert, Robert A.

    2015-01-01

    We examined whether romantic relationship satisfaction would serve as a link between early and later stressors which in turn would influence the Thyroid Function Index (TFI), an indicator of physiological stress response. Using the framework of genetic susceptibility theory combined with hypotheses derived from the vulnerability-stress-adaptation and stress-generation models, we tested whether the hypothesized mediational model would be conditioned by 5-HTTLPR genotype, with greater effects and stronger evidence of mediation among carriers of the “s” allele. In a sample of African American women in romantic relationships (n = 270), we found that 5-HTTLPR moderated each stage of the hypothesized mediational model in a “for better or for worse” manner. That is genetic polymorphisms function to exacerbate not only the detrimental impact of negative environments (i.e. “for worse effects”) but also the beneficial impact of positive environments (i.e. “for better effects”). The effect of early stress on relationship satisfaction was greater among carriers of the “short” allele than among those who did not carry the short allele, and was significantly different in both the “for better” and “for worse” direction. Likewise, the effect of relationship satisfaction on later stressors was moderated in a “for better” or “for worse” manner. Finally, impact on physiological stress, indexed using TFI level, indicated that the impact of later stressors on TFI level was greater in the presence of the short allele, and also followed a “for better” or “for worse” pattern. As expected, the proposed mediational model provided a better fit for “s” allele carriers. PMID:26376424

  5. Moderate Childhood Stress Buffers Against Depressive Response to Proximal Stressors: A Multi-Wave Prospective Study of Early Adolescents

    Science.gov (United States)

    Shapero, Benjamin G.; Hamilton, Jessica L.; Stange, Jonathan P.; Liu, Richard T.; Y.Abramson, Lyn; Alloy, Lauren B.

    2015-01-01

    Although the majority of research in the field has focused on childhood stressors as a risk factor for psychopathology, a burgeoning body of literature has focused on the possible steeling effect of moderate types of stressful events. The current study investigated the effects of proximal life stressors on prospective changes in depressive symptoms, and whether a history of moderate childhood adversity would moderate this relationship in a multi-wave study of a diverse community sample of early adolescents (N = 163, 52% female, 51% Caucasian). Hierarchical linear modeling was run with four waves of data. Adolescents with greater moderately severe early life events evinced a blunted depressive symptom response to changes in proximal stressful events in the previous 9 months, compared to those with fewer early moderately severe experiences of adversity. These results held after controlling for between-subject factors such as race, gender, severe early life stress, and average stress over the four waves of data. Findings indicate that greater exposure to moderate childhood stressors may buffer against the negative effects of subsequent stressors, suggesting the importance of a nuanced developmental approach to studying the effects of early life stress. PMID:25911194

  6. Moderate Childhood Stress Buffers Against Depressive Response to Proximal Stressors: A Multi-Wave Prospective Study of Early Adolescents.

    Science.gov (United States)

    Shapero, Benjamin G; Hamilton, Jessica L; Stange, Jonathan P; Liu, Richard T; Abramson, Lyn Y; Alloy, Lauren B

    2015-11-01

    Although the majority of research in the field has focused on childhood stressors as a risk factor for psychopathology, a burgeoning body of literature has focused on the possible steeling effect of moderate types of stressful events. The current study investigated the effects of proximal life stressors on prospective changes in depressive symptoms, and whether a history of moderate childhood adversity would moderate this relationship in a multi-wave study of a diverse community sample of early adolescents (N = 163, 52 % female, 51 % Caucasian). Hierarchical linear modeling was run with four waves of data. Adolescents with greater moderately severe early life events evinced a blunted depressive symptom response to changes in proximal stressful events in the previous 9 months, compared to those with fewer early moderately severe experiences of adversity. These results held after controlling for between-subject factors such as race, gender, severe early life stress, and average stress over the four waves of data. Findings indicate that greater exposure to moderate childhood stressors may buffer against the negative effects of subsequent stressors, suggesting the importance of a nuanced developmental approach to studying the effects of early life stress.

  7. Social support moderates the effects of stress on sleep in adolescents.

    Science.gov (United States)

    van Schalkwijk, Frank J; Blessinga, Agaath N; Willemen, Agnes M; Van Der Werf, Ysbrand D; Schuengel, Carlo

    2015-08-01

    Academic expectations and demands become primary sources of stress during adolescence, negatively affecting sleep. To cope with stress, adolescents may turn to social support figures. The present study tested the extent of main and moderating effects of various sources of social support on the association between stress and sleep. Adolescents (n = 202, meanage 14.6 years, standard deviation = 0.71) reported on academic stress, sleep, and support using questionnaires during a low- and high-stress period, defined by the absence or presence of examinations, respectively. Inquiries were made regarding social support from parents, friends, and class supervisor. During both stress periods, academic stress was associated negatively with sleep quality and positively with sleep reduction. Social support increased sleep quality and lowered sleep reduction. In addition, social support moderated the effects of academic stress on sleep, thus improving sleep quality and lowering sleep reduction. Moderating effects were stronger during a period of high stress. The present study showed that adolescents can benefit from stress moderation through social support by improvements of sleep quality and sleep reduction. Such moderating effects should be taken into account when studying stress and sleep. Implications and recommendations based on these findings are discussed. © 2015 European Sleep Research Society.

  8. Assessments of the stresses and deformations in an RBMK graphite moderator brick

    International Nuclear Information System (INIS)

    Jones, C.J.; Davies, M.A.; Marsden, B.J.; Bougaenko, S.E.; Baldin, V.D.; Demintievski, V.N.; Rodtchenkov, B.S.; Sinitsyn, E.N.

    1996-01-01

    The RBMK reactors, designed by RDIPE (Moscow), are graphite moderated and cooled by light water. Graphite dimensions and thermo-mechanical properties change significantly in a complex manner during reactor life due to fast neutron damage and these changes have implications on the safe operation of all graphite moderated reactors. A joint programme of work is being carried out between AEA Technology (UK) and RDIPE (Russia) to assess the life of the RBMK graphite stack under normal operating conditions. The programme has included the modelling of graphite dimensional changes due to irradiation through reactor life and the assessment of the implications of these changes on the stresses and deformations in the graphite stack. Calculations have been carried out to assess the deformations of a moderator brick over a period from start of life up to 30 years of operation. The assessment have also included an analysis of the stresses in the bricks so that the time to brick failure could be determined. This paper describes the RBMK core design, the data and assessment methodology used in the analysis of the RBMK core and presents some results from analyses of the Leningrad Unit 1 RBMK reactor. (author). 2 refs, 8 figs

  9. Teacher Stress Predicts Child Executive Function: Moderation by School Poverty

    Science.gov (United States)

    Neuenschwander, Regula; Friedman-Krauss, Allison; Raver, Cybele; Blair, Clancy

    2017-01-01

    Research Findings: Recent research has explored relations between classroom quality and child executive function (EF), but little is known about how teachers' well-being, including stress, relates to child EF--a crucial component of self-regulation. We hypothesized that teacher stress is negatively or curvilinearly related to child EF and…

  10. The Moderating Effect of Perceived Social Support on Stress and Depression among University Students

    Directory of Open Access Journals (Sweden)

    Prashanth Talwar

    2016-10-01

    Full Text Available Background and objectives: The omnipresence of stress and depression among university students is a cause for concern, as it can have adverse consequences on all aspects of their life. Understanding the role of social support as a protective factor within this context, may well be vital to the enhancement of overall wellbeing among students. The main aim of the present study was to examine the moderating effect of perceived social support on the relationship between stress and depression. Methods: A cross-sectional survey was conducted to garner data from 254 university students for hierarchical multiple regression and structural equation modeling analysis. Results: Firstly, the present study replicated the frequently reported positive relationship between stress and depression. Secondly, an inverse association between social support and depression was also depicted. Finally, the results also supported an interaction between perceived social support and stress in predicting depression among students. Conclusion: In sum, the results of the current study may well augment our understanding of the role of perceived social support in combating stress and depression among students, and thereby convey important implications for intervention strategies tailored to this demographic.

  11. The moderating role of meaning in life in the relationship between perceived stress and diurnal cortisol.

    Science.gov (United States)

    Pulopulos, Matias M; Kozusznik, Malgorzata W

    2018-05-01

    Previous studies have suggested that meaning in life may buffer the negative effects of stress. This study is the first to investigate the moderating role of meaning in life in the relationship between the perception of stress and diurnal cortisol in two independent samples of healthy adults. In study 1 (n = 172, men = 82, women = 90, age range = 21-55 years, mean age = 37.58 years), the results of moderated regression analyses revealed that there was a significant positive relationship between overall perceived stress in the past month and both diurnal cortisol levels (area-under-the-curve with respect to the ground; AUCg) and the diurnal cortisol slope (DCS) only in individuals with low levels of meaning in life conceptualized as the degree to which one engages in activities that are personally valued and important. In study 2 (n = 259, men = 125, women = 134, age range = 18-54 years, mean age = 29.06 years), we found a non-significant interaction term between meaning in life conceptualized as having goals and a sense of excitement regarding one's future and perception of stress in a model of both adjusted AUCg and DCS. The results were independent of age, sex, body mass index, education, and race. The results shed light on the importance and the complexity of the construct of meaning in life and offer a possible explanation for why some people who face stressors may be more vulnerable than others to developing stress-related health problems.

  12. Social support moderates the effects of stress on sleep in adolescents

    OpenAIRE

    van Schalkwijk, Frank J; Blessinga, Agaath N; Willemen, Agnes M; Van Der Werf, Ysbrand D; Schuengel, Carlo

    2015-01-01

    Academic expectations and demands become primary sources of stress during adolescence, negatively affecting sleep. To cope with stress, adolescents may turn to social support figures. The present study tested the extent of main and moderating effects of various sources of social support on the association between stress and sleep. Adolescents (n = 202, meanage 14.6 years, standard deviation = 0.71) reported on academic stress, sleep, and support using questionnaires during a low- and high-str...

  13. For whom does mindfulness-based stress reduction work? : An examination of moderating effects of personality

    NARCIS (Netherlands)

    Nyklicek, I.; Irrmischer, M.

    2017-01-01

    The aim of the present study was to examine potentially moderating effects of personality characteristics regarding changes in anxious and depressed mood associated with Mindfulness-Based Stress Reduction (MBSR), controlling forsociodemographicactors.Meditation-naïvearticipants from the general

  14. [Nearby nature as a moderator of stress during childhood].

    Science.gov (United States)

    Corraliza, José Antonio; Collado, Silvia

    2011-04-01

    The aim of this investigation is to study the relation between the amount of nature existing in children's daily environments and the way children deal with stressful events. Every day, children are exposed to situations that cause stress. Taking into account previous studies, it is thought that the greener the place where children spend their time, the better they cope with adversities. Thus, when comparing the stress level of children who are exposed to the same amount of adverse situations, the children who have more frequent daily contact with nature will show less stress than those who do not spend time in nature. This effect from nearby nature is called a buffering effect. The present study provides empirical evidence of the buffering effect caused by the existence of Nature in the residential and the school environment. Therefore, our results show that children who have more access to nature increase their resilience, showing a lower stress level than children whose contact with nature is less frequent.

  15. History of sexual trauma moderates psychotherapy outcome for posttraumatic stress disorder.

    Science.gov (United States)

    Markowitz, John C; Neria, Yuval; Lovell, Karina; Van Meter, Page E; Petkova, Eva

    2017-08-01

    Moderators of differential psychotherapy outcome for posttraumatic stress disorder (PTSD) are rare, yet have crucial clinical importance. We tested the moderating effects of trauma type for three psychotherapies in 110 unmedicated patients with chronic DSM-IV PTSD. Patients were randomized to 14 weeks of prolonged exposure (PE, N = 38), interpersonal psychotherapy (IPT, N = 40), or relaxation therapy (RT, N = 32). The Clinician-Administered PTSD Scale (CAPS) was the primary outcome measure. Moderator candidates were trauma type: interpersonal, sexual, physical. We fit a regression model for week 14 CAPS as a function of treatment (a three-level factor), an indicator of trauma type presence/absence, and their interactions, controlling for baseline CAPS, and evaluated potential confounds. Thirty-nine (35%) patients reported sexual, 68 (62%) physical, and 102 (93%) interpersonal trauma. Baseline CAPS scores did not differ by presence/absence of trauma types. Sexual trauma as PTSD criterion A significantly moderated treatment effect: whereas all therapies had similar efficacy among nonsexually-traumatized patients, IPT had greater efficacy among sexually traumatized patients (efficacy difference with and without sexual trauma: IPT vs. PE and IPT vs. RT P's < .05), specifically in PTSD symptom clusters B and D (P's < .05). Few studies have assessed effects of varying trauma types on effects of differing psychotherapies. In this exploratory study, sexual trauma moderated PTSD outcomes of three therapies: IPT showed greater benefit for sexually traumatized patients than PE or RT. The IPT focuses on affect to help patients determine trust in their current environments may particularly benefit patients who have suffered sexual assault. © 2017 Wiley Periodicals, Inc.

  16. Life Changes and Social Support: Stress and Its Moderators.

    Science.gov (United States)

    1981-04-17

    enjoy traveling to strange places, prefer the unfamiliar to the familiar, and participate in activities such as skydiving, automobile racing... automobile drivers stop. Other situations are universally salient because their overwhelming characteristics evoke similar stress reactions in large...883 6 November 1979 LIST 7 HRM Officer in Charge Human Resource Management Detachment Naval Air Station Alameda, CA 94591 Officer in Charge Human

  17. Stress and performance: do service orientation and emotional energy moderate the relationship?

    Science.gov (United States)

    Smith, Michael R; Rasmussen, Jennifer L; Mills, Maura J; Wefald, Andrew J; Downey, Ronald G

    2012-01-01

    The current study examines the moderating effect of customer service orientation and emotional energy on the stress-performance relationship for 681 U.S. casual dining restaurant employees. Customer service orientation was hypothesized to moderate the stress-performance relationship for Front-of-House (FOH) workers. Emotional energy was hypothesized to moderate stress-performance for Back-of-House (BOH) workers. Contrary to expectations, customer service orientation failed to moderate the effects of stress on performance for FOH employees, but the results supported that customer service orientation is likely a mediator of the relationship. However, the hypothesis was supported for BOH workers; emotional energy was found to moderate stress performance for these employees. This finding suggests that during times of high stress, meaningful, warm, and empathetic relationships are likely to impact BOH workers' ability to maintain performance. These findings have real-world implications in organizational practice, including highlighting the importance of developing positive and meaningful social interactions among workers and facilitating appropriate person-job fits. Doing so is likely to help in alleviating worker stress and is also likely to encourage worker performance.

  18. Social support moderates the effects of stress on sleep in adolescents

    NARCIS (Netherlands)

    van Schalkwijk, Frank J; Blessinga, Agaath N; Willemen, Agnes M; Van Der Werf, Ysbrand D; Schuengel, Carlo

    Academic expectations and demands become primary sources of stress during adolescence, negatively affecting sleep. To cope with stress, adolescents may turn to social support figures. The present study tested the extent of main and moderating effects of various sources of social support on the

  19. Moderate alcohol consumption after a mental stressor attenuates the endocrine stress response

    NARCIS (Netherlands)

    Schrieks, I.C.; Joosten, M.M.; Klöpping-Ketelaars, W.A.A.; Witkamp, R.F.; Hendriks, H.F.J.

    2016-01-01

    Alcohol is often consumed to reduce tension and improve mood when exposed to stressful situations. Previous studies showed that moderate alcohol consumption may reduce stress when alcohol is consumed prior to a stressor, but data on the effect of alcohol consumption after a mental stressor is

  20. Moderate alcohol consumption after a mental stressor attenuates the endocrine stress response

    NARCIS (Netherlands)

    Schrieks, I.C.; Joosten, M.M.; Klöpping-Ketelaars, W.A.A.; Witkamp, R.F.; Hendriks, H.F.J.

    2016-01-01

    Alcohol is often consumed to reduce tension and improve mood when exposed to stressful situations. Previous studies showed that moderate alcohol consumption may reduce stress when alcohol is consumed prior to a stressor, but data on the effect of alcohol consumption after a mental stressor is

  1. Does Self-Esteem Moderate the Relations among Perceived Stress, Coping, and Depression?

    Science.gov (United States)

    Eisenbarth, Chris

    2012-01-01

    This study examined self-esteem as a moderator of the influence of perceived stress and coping on symptoms of depression in a sample of 713 college students. The results suggest that self-esteem may play an important role in the development of depressive symptoms in college students through interactions with perceived stress and coping. If an…

  2. College Stress and Psychological Well-Being: Self-Transcendence Meaning of Life as a Moderator

    Science.gov (United States)

    Hong, Li

    2008-01-01

    The central aim of this study is to examine the moderating effects of self-transcendence meaning on psychological well-being in respective of college students. The theoretical background of self-transcendence meaning is mainly oriental Buddhism and Taoism philosophy. Measures of stress and psychological well-being are College Stress Scale (CSS)…

  3. Associations of social support and stress with postpartum maternal mental health symptoms: Main effects, moderation, and mediation.

    Science.gov (United States)

    Schwab-Reese, Laura M; Schafer, Ellen J; Ashida, Sato

    2017-07-01

    Poor maternal mental health during the postpartum period can have significant effects on the health of mothers, infants, and families. The findings from cross-sectional studies suggest that stress and social support are related to maternal mental health. This study contributes to the literature through the use of longitudinal data, and examines moderation and mediation among these factors. In 2012-2013, mothers completed surveys assessing stress, social support, and depressive and anxiety symptoms following birth (n = 125), and 3 months (n = 110) and 6 months (n = 99) after birth. The authors examined temporal associations, moderation, and mediation of social support on the relationship between stress and postpartum depressive and anxiety symptoms using modified Poisson regression models and the counterfactual approach to mediation. Current levels of stress and social support were associated with depressive and anxiety symptoms, both independently and when considered together at multiple time points. Social support did not strongly moderate or mediate the relationships between stress and maternal mental health. Interventions to reduce current perceptions of stress and increase social support for mothers during the postpartum period may help improve maternal mental health symptoms. Efforts are needed to assess the current needs of mothers continuously.

  4. Anxiety, affect, self-esteem, and stress: mediation and moderation effects on depression.

    Science.gov (United States)

    Nima, Ali Al; Rosenberg, Patricia; Archer, Trevor; Garcia, Danilo

    2013-01-01

    Mediation analysis investigates whether a variable (i.e., mediator) changes in regard to an independent variable, in turn, affecting a dependent variable. Moderation analysis, on the other hand, investigates whether the statistical interaction between independent variables predict a dependent variable. Although this difference between these two types of analysis is explicit in current literature, there is still confusion with regard to the mediating and moderating effects of different variables on depression. The purpose of this study was to assess the mediating and moderating effects of anxiety, stress, positive affect, and negative affect on depression. Two hundred and two university students (males  = 93, females  = 113) completed questionnaires assessing anxiety, stress, self-esteem, positive and negative affect, and depression. Mediation and moderation analyses were conducted using techniques based on standard multiple regression and hierarchical regression analyses. The results indicated that (i) anxiety partially mediated the effects of both stress and self-esteem upon depression, (ii) that stress partially mediated the effects of anxiety and positive affect upon depression, (iii) that stress completely mediated the effects of self-esteem on depression, and (iv) that there was a significant interaction between stress and negative affect, and between positive affect and negative affect upon depression. The study highlights different research questions that can be investigated depending on whether researchers decide to use the same variables as mediators and/or moderators.

  5. Anxiety, affect, self-esteem, and stress: mediation and moderation effects on depression.

    Directory of Open Access Journals (Sweden)

    Ali Al Nima

    Full Text Available Mediation analysis investigates whether a variable (i.e., mediator changes in regard to an independent variable, in turn, affecting a dependent variable. Moderation analysis, on the other hand, investigates whether the statistical interaction between independent variables predict a dependent variable. Although this difference between these two types of analysis is explicit in current literature, there is still confusion with regard to the mediating and moderating effects of different variables on depression. The purpose of this study was to assess the mediating and moderating effects of anxiety, stress, positive affect, and negative affect on depression.Two hundred and two university students (males  = 93, females  = 113 completed questionnaires assessing anxiety, stress, self-esteem, positive and negative affect, and depression. Mediation and moderation analyses were conducted using techniques based on standard multiple regression and hierarchical regression analyses.The results indicated that (i anxiety partially mediated the effects of both stress and self-esteem upon depression, (ii that stress partially mediated the effects of anxiety and positive affect upon depression, (iii that stress completely mediated the effects of self-esteem on depression, and (iv that there was a significant interaction between stress and negative affect, and between positive affect and negative affect upon depression.The study highlights different research questions that can be investigated depending on whether researchers decide to use the same variables as mediators and/or moderators.

  6. Anxiety, Affect, Self-Esteem, and Stress: Mediation and Moderation Effects on Depression

    Science.gov (United States)

    Nima, Ali Al; Rosenberg, Patricia; Archer, Trevor; Garcia, Danilo

    2013-01-01

    Background Mediation analysis investigates whether a variable (i.e., mediator) changes in regard to an independent variable, in turn, affecting a dependent variable. Moderation analysis, on the other hand, investigates whether the statistical interaction between independent variables predict a dependent variable. Although this difference between these two types of analysis is explicit in current literature, there is still confusion with regard to the mediating and moderating effects of different variables on depression. The purpose of this study was to assess the mediating and moderating effects of anxiety, stress, positive affect, and negative affect on depression. Methods Two hundred and two university students (males  = 93, females  = 113) completed questionnaires assessing anxiety, stress, self-esteem, positive and negative affect, and depression. Mediation and moderation analyses were conducted using techniques based on standard multiple regression and hierarchical regression analyses. Main Findings The results indicated that (i) anxiety partially mediated the effects of both stress and self-esteem upon depression, (ii) that stress partially mediated the effects of anxiety and positive affect upon depression, (iii) that stress completely mediated the effects of self-esteem on depression, and (iv) that there was a significant interaction between stress and negative affect, and between positive affect and negative affect upon depression. Conclusion The study highlights different research questions that can be investigated depending on whether researchers decide to use the same variables as mediators and/or moderators. PMID:24039896

  7. Moderators and Mediators of the Relationship Between Stress and Insomnia: Stressor Chronicity, Cognitive Intrusion, and Coping

    Science.gov (United States)

    Pillai, Vivek; Roth, Thomas; Mullins, Heather M.; Drake, Christopher L.

    2014-01-01

    Study Objectives: To assess moderators, such as stressor chronicity, and mediators, including stress response in the form of cognitive intrusion and coping behavior, of the prospective association between naturalistic stress and incident insomnia. Design: Longitudinal. Setting: Epidemiological. Participants: A community-based sample of good sleepers (n = 2,892) with no lifetime history of insomnia. Interventions: None. Measurements and Results: Participants reported the number of stressful events they had encountered at baseline, as well as the perceived severity and chronicity of each event. Similarly, volitional stress responses such as coping, as well as more involuntary responses such as cognitive intrusion were assayed for each stressor. Follow-up assessment 1 y hence revealed an insomnia incidence rate of 9.1%. Stress exposure was a significant predictor of insomnia onset, such that the odds of developing insomnia increased by 19% for every additional stressor. Chronicity significantly moderated this relationship, such that the likelihood of developing insomnia as a result of stress exposure increased as a function of chronicity. Cognitive intrusion significantly mediated the association between stress exposure and insomnia. Finally, three specific coping behaviors also acted as mediators: behavioral disengagement, distraction, and substance use. Conclusions: Most studies characterize the relationship between stress exposure and insomnia as a simple dose-response phenomenon. However, our data suggest that certain stressor characteristics significantly moderate this association. Stress response in the form of cognitive intrusion and specific maladaptive coping behaviors mediate the effects of stress exposure. These findings highlight the need for a multidimensional approach to stress assessment in future research and clinical practice. Citation: Pillai V, Roth T, Mullins HM, Drake CL. Moderators and mediators of the relationship between stress and insomnia

  8. Moderation analysis using a two-level regression model.

    Science.gov (United States)

    Yuan, Ke-Hai; Cheng, Ying; Maxwell, Scott

    2014-10-01

    Moderation analysis is widely used in social and behavioral research. The most commonly used model for moderation analysis is moderated multiple regression (MMR) in which the explanatory variables of the regression model include product terms, and the model is typically estimated by least squares (LS). This paper argues for a two-level regression model in which the regression coefficients of a criterion variable on predictors are further regressed on moderator variables. An algorithm for estimating the parameters of the two-level model by normal-distribution-based maximum likelihood (NML) is developed. Formulas for the standard errors (SEs) of the parameter estimates are provided and studied. Results indicate that, when heteroscedasticity exists, NML with the two-level model gives more efficient and more accurate parameter estimates than the LS analysis of the MMR model. When error variances are homoscedastic, NML with the two-level model leads to essentially the same results as LS with the MMR model. Most importantly, the two-level regression model permits estimating the percentage of variance of each regression coefficient that is due to moderator variables. When applied to data from General Social Surveys 1991, NML with the two-level model identified a significant moderation effect of race on the regression of job prestige on years of education while LS with the MMR model did not. An R package is also developed and documented to facilitate the application of the two-level model.

  9. Underground water stress release models

    Science.gov (United States)

    Li, Yong; Dang, Shenjun; Lü, Shaochuan

    2011-08-01

    The accumulation of tectonic stress may cause earthquakes at some epochs. However, in most cases, it leads to crustal deformations. Underground water level is a sensitive indication of the crustal deformations. We incorporate the information of the underground water level into the stress release models (SRM), and obtain the underground water stress release model (USRM). We apply USRM to the earthquakes occurred at Tangshan region. The analysis shows that the underground water stress release model outperforms both Poisson model and stress release model. Monte Carlo simulation shows that the simulated seismicity by USRM is very close to the real seismicity.

  10. Towards a moderated mediation model of innovative work behaviour enhancement

    NARCIS (Netherlands)

    Stoffers, Jol M.; van der Heijden, Beatrice; Notelaers, Guy L.A.

    2014-01-01

    Purpose – The purpose of this paper is to investigate a moderated mediation model of innovative work behaviour enhancement. Perceived firm (organizational and market) performance was assumed to moderate the relationships between leader-member exchange (LMX) and organizational citizenship behaviour

  11. Parenting stress and harsh discipline in China: The moderating roles of marital satisfaction and parent gender.

    Science.gov (United States)

    Liu, Li; Wang, Meifang

    2015-05-01

    This research examined the relationships between parents' parenting stress and their harsh discipline (psychological aggression and corporal punishment) and the moderating effects of marital satisfaction and parent gender in Chinese societies. Using a sample of 639 Chinese father-mother dyads with preschoolers, findings revealed that both mothers' and fathers' parenting stress were directly associated with their harsh discipline. Mothers' marital satisfaction attenuated the association between their parenting stress and harsh discipline. However, fathers' marital satisfaction did not moderate the association between their parenting stress and harsh discipline. Findings from the current study highlight the importance of considering how the dyadic marital relationship factors may interact with individuals' parenting stress to influence both maternal and paternal disciplinary behaviors. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Intergenerational transmission of harsh discipline: The moderating role of parenting stress and parent gender.

    Science.gov (United States)

    Niu, Hua; Liu, Li; Wang, Meifang

    2018-05-01

    The present study examined the intergenerational transmission of harsh discipline (psychological aggression and corporal punishment) and the moderating effects of parenting stress and parent gender in Chinese societies. Utilizing a sample of 634 Chinese father-mother dyads with preschoolers, findings revealed that both mothers' and fathers' harsh discipline were transmitted across generations and the strength of transmission varied by the severity of harsh discipline and the parent gender. For both mothers and fathers, high parenting stress intensified the intergenerational transmission of psychological aggression and corporal punishment, whereas low parenting stress weakened the transmission of psychological aggression and even disrupted the transmission of corporal punishment. Moreover, the moderating effects of parenting stress on the transmission were stronger for mothers than for fathers. Findings from the present study highlight the importance of considering how the proximal environmental factors (such as parenting stress) may influence the intergenerational transmission of harsh discipline. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Stress moderates the relationships between problem-gambling severity and specific psychopathologies.

    Science.gov (United States)

    Ronzitti, Silvia; Kraus, Shane W; Hoff, Rani A; Potenza, Marc N

    2018-01-01

    The purpose of this study was to examine the extent to which stress moderated the relationships between problem-gambling severity and psychopathologies. We analyzed Wave-1 data from 41,869 participants of the National Epidemiologic Survey of Alcohol and Related Conditions (NESARC). Logistic regression showed that as compared to a non-gambling (NG) group, individuals at-risk gambling (ARG) and problem gambling (PPG) demonstrated higher odds of multiple Axis-I and Axis-II disorders in both high- and low-stress groups. Interactions odds ratios were statistically significant for stress moderating the relationships between at-risk gambling (versus non-gambling) and Any Axis-I and Any Axis-II disorder, with substance-use and Cluster-A and Cluster-B disorders contributing significantly. Some similar patterns were observed for pathological gambling (versus non-gambling), with stress moderating relationships with Cluster-B disorders. In all cases, a stronger relationship was observed between problem-gambling severity and psychopathology in the low-stress versus high-stress groups. The findings suggest that perceived stress accounts for some of the variance in the relationship between problem-gambling severity and specific forms of psychopathology, particularly with respect to lower intensity, subsyndromal levels of gambling. Findings suggest that stress may be particularly important to consider in the relationships between problem-gambling severity and substance use and Cluster-B disorders. Published by Elsevier B.V.

  14. Job Stress and Police Burnout: Moderating Roles of Gender and Marital Status

    Directory of Open Access Journals (Sweden)

    Bolanle Ogungbamila

    2016-12-01

    Full Text Available Previous studies on occupational burnout among police personnel did not pay enough attention to how gender and marital status may influence the connection between job stress and occupational burnout, especially where cultural beliefs direct gender and marital issues in relation to work, such as Nigeria. This study, therefore, investigated the extent to which gender and marital status moderate the relationship between job stress and occupational burnout. Participants were 213 police personnel (male = 120; female = 93 selected from 10 urban and 10 semi-urban police divisions in Nigeria. Their ages ranged between 20 and 54 years (Mage=38.15 years; SD =10.0. Results revealed that job stress significantly predicted occupational burnout such that an increase in job stress led to increase in the level of occupational burnout. Gender moderated the effects of job stress on occupational burnout in such a way that job stress tended to result in higher level of occupational burnout in female than in male police personnel. Similarly, marital status moderated the relationship between job stress and occupational burnout in such a way that police personnel who were married tended to report higher level of occupational burnout in the presence of job stress than those who were single. Implications for gender sensitivity and family supportiveness were discussed.

  15. Academic stress and positive affect: Asian value and self-worth contingency as moderators among Chinese international students.

    Science.gov (United States)

    Liao, Kelly Yu-Hsin; Wei, Meifen

    2014-01-01

    The theoretical model proposed by Berry and colleagues (Berry, 1997; Berry, Kim, Minde, & Mok, 1987) highlights the importance of identifying moderators in the acculturation process. Accordingly, the current study examined the Asian cultural value of family recognition through achievement (FRTA) and contingency of self-worth on academic competence (CSW-AC) as moderators in the association between academic stress and positive affect among Chinese international students. A total of 370 Chinese international students completed online surveys. Results from a hierarchical regression indicated that while academic stress was negatively associated with positive affect, FRTA was positively associated with positive affect. In other words, those with high academic stress reported a lower level of positive affect. However, individuals who endorsed high levels of FRTA reported a higher level of positive affect. In addition, results also revealed a significant interaction between academic stress and CSW-AC on positive affect. Thus, the study's finding supported the moderator role of CSW-AC. Simple effect analyses were conducted to examine the significant interaction. The results showed that higher levels of CSW-AC strengthened the negative association between academic stress and positive affect but lower levels of CSW-AC did not. Future research directions and implications are discussed.

  16. Organizational Stress as Moderator of Relationship Between Mental Health Provider Adaptability and Organizational Commitment.

    Science.gov (United States)

    Green, Amy E; Dishop, Christopher R; Aarons, Gregory A

    2016-10-01

    Community mental health providers often operate within stressful work environments and are at high risk of emotional exhaustion, which can negatively affect job performance and client satisfaction with services. This cross-sectional study examined the relationships between organizational stress, provider adaptability, and organizational commitment. Variables were analyzed with moderated multilevel regression in a sample of 311 mental health providers from 49 community mental health programs. Stressful organizational climate, characterized by high levels of emotional exhaustion, role conflict, and role overload, was negatively related to organizational commitment. Organizational stress moderated the relationship between provider adaptability and organizational commitment, such that those who were more adaptable had greater levels of organizational commitment when organizational stress was low but were less committed than those who were less adaptable when organizational stress was high. Providers higher in adaptability may perceive their organization as a greater fit when the work environment is less stressful; however, highly adaptable providers may also exercise choice that manifests in lower commitment to staying in an overly stressful work environment. Service systems and organizational contexts are becoming increasingly demanding and stressful for direct mental health service providers. Therefore, community mental health organizations should assess and understand their organizational climate and intervene with empirically based organizational strategies when necessary to reduce stressful climates and maintain adaptable employees.

  17. Organizational Stress Moderates the Relationship between Mental Health Provider Adaptability and Organizational Commitment

    Science.gov (United States)

    Green, Amy E.; Dishop, Christopher; Aarons, Gregory A

    2016-01-01

    Objective Community mental health providers often operate within stressful work environments and are at high risk for emotional exhaustion, which can negatively affect job performance and client satisfaction with services. This cross-sectional study examines the relationships between organizational stress, provider adaptability, and organizational commitment. Methods Variables were analyzed using moderated multi-level regression in a sample of 311 mental health providers from 49 community mental health programs. Results Stressful organizational climate, characterized by high levels of emotional exhaustion, role conflict, and role overload, was negatively related to organizational commitment. Organizational stress moderated the relationship between provider adaptability and organizational commitment, such that those who were more adaptable had greater levels of organizational commitment when organizational stress was low, but were less committed than those who were less adaptable when organizational stress was high. Conclusions In the current study, providers higher in adaptability may perceive their organization as a greater fit when characterized by lower levels of stressfulness; however, highly adaptable providers may also exercise choice that manifests in lower commitment to staying in an overly stressful work environment. Service systems and organizational contexts are becoming increasingly demanding and stressful for direct mental health service providers. Therefore, community mental health organizations should assess and understand their organizational climate and intervene with empirically based organizational strategies when necessary to reduce stressful climates and maintain desirable employees. PMID:27301760

  18. Parent-adolescent relationship and adolescent internet addiction: A moderated mediation model.

    Science.gov (United States)

    Wang, Wei; Li, Dongping; Li, Xian; Wang, Yanhui; Sun, Wenqiang; Zhao, Liyan; Qiu, Lilan

    2018-09-01

    Substantial research has found that positive parent-adolescent relationship is associated with low levels of adolescent Internet addiction (IA). However, little is known about the mediating and moderating mechanisms underlying this relation. The present study examined a moderated mediation model that included the parent-adolescent relationship (predictor variable), emotion regulation ability (mediator), stressful life events (moderator), and IA (outcome variable) simultaneously. A total of 998 (M age  = 15.15 years, SD = 1.57) Chinese adolescents completed the Parent-Adolescent Relationship Scale, Emotion Regulation Ability Scale, Adolescent Stressful Life Events Scale, and Internet Addiction Diagnostic Questionnaire. After controlling for adolescent gender, age, and family socioeconomic status, results revealed that good parent-adolescent relationship was positively associated with adolescent emotion regulation ability, which in turn was negatively associated with their IA. Moreover, stressful life events moderated the second part of the mediation process. In accordance with the reverse stress-buffering model, the relation between emotion regulation ability and adolescent IA was stronger for adolescents who experienced lower levels of stressful life events. The findings and their implications are discussed and a resilient contextual perspective proposed. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. Neutronic characteristics of coupled moderator proposed in integrated model

    International Nuclear Information System (INIS)

    Teshigawara, Makoto; Meigo, Shin-ichiro; Sakata, Hideaki; Kai, Tetsuya; Harada, Masahide; Ikeda, Yujiro; Watanabe, Noboru

    2001-05-01

    A pulsed spallation source for the materials science and the life science is currently developing for its construction in the High Intensity Proton Accelerator Project proposed jointly by the Japan Atomic Energy Research Institute (JAERI) and the High Energy Accelerator Research Organization (KEK). This report presents the analytical results of the neutronic characteristics of the coupled moderator based on the analytical results obtained by using an integrated model which has established on the extensive neutronic and technical study. Total heat deposition in a hydrogen (H 2 ) moderator working as the main moderator was about 420 W/MW. Maximum nuclear heat density in the H 2 moderator was about 1 W/cm 3 /MW. Also total heat deposition in a premoderator was about 9.2 kW/MW. The heat density of the premoderator was comparable to that of the moderator vessel made of aluminum alloy. The heat density of the premoderator and the moderator vessel is about 1.2-2 times higher than that of the hydrogen moderator. The temperature from 300 K to 400 K of the premoderator did not affect on neutron intensity of the H 2 moderator. This suggested an engineering advantage on the thermal and hydraulic design. 6000 or 7000 type of a aluminum alloy was considered from the viewpoint of the neutron beam transmission. The proton beams scattered by the proton beam window did not affect on the nuclear heating in the H 2 moderator. The heat deposition in the H 2 moderator and the neutron intensity of the H 2 moderator did not depend on the proton beam profile but it did on the distance between the proton beam and the moderator. (author)

  20. Family cohesion moderates the relationship between acculturative stress and depression in Japanese adolescent temporary residents.

    Science.gov (United States)

    Roley, Michelle E; Kawakami, Ryoko; Baker, Jessica; Hurtado, Gabriela; Chin, Andrew; Hovey, Joseph D

    2014-12-01

    Acculturative stress is a risk factor for depression, and may be important in the risk for depression among acculturating Japanese adolescents. However, little to no research has been published on the mental health of acculturating Japanese adolescents. Further, although family cohesion has been shown to be protective against depression across ethnic groups, no prior research has examined family cohesion as a protective factor for Japanese adolescents. To examine these relationships, 26 Japanese temporary resident adolescents and 76 parents in the Midwest were recruited to participate. Moderate to strong correlations between acculturative stress, depression, likelihood for and seriousness of family conflict were found. A regression analysis found that likelihood for family conflict moderated the relationship between acculturative stress and depression. Findings broaden our understanding of the role of acculturative stress and family conflict on depression risk for Japanese adolescent immigrants.

  1. Links between white matter microstructure and cortisol reactivity to stress in early childhood: Evidence for moderation by parenting

    Directory of Open Access Journals (Sweden)

    Haroon I. Sheikh

    2014-01-01

    Full Text Available Activity of the hypothalamic–pituitary–adrenal axis (measured via cortisol reactivity may be a biological marker of risk for depression and anxiety, possibly even early in development. However, the structural neural correlates of early cortisol reactivity are not well known, although these would potentially inform broader models of mechanisms of risk, especially if the early environment further shapes these relationships. Therefore, we examined links between white matter architecture and young girls' cortisol reactivity and whether early caregiving moderated these links. We recruited 45 6-year-old girls based on whether they had previously shown high or low cortisol reactivity to a stress task at age 3. White matter integrity was assessed by calculating fractional anisotropy (FA of diffusion-weighted magnetic resonance imaging scans. Parenting styles were measured via a standardized parent–child interaction task. Significant associations were found between FA in white matter regions adjacent to the left thalamus, the right anterior cingulate cortex, and the right superior frontal gyrus (all ps < .001. Further, positive early caregiving moderated the effect of high cortisol reactivity on white matter FA (all ps ≤ .05, with high stress reactive girls who received greater parent positive affect showing white matter structure more similar to that of low stress reactive girls. Results show associations between white matter integrity of various limbic regions of the brain and early cortisol reactivity to stress and provide preliminary support for the notion that parenting may moderate associations.

  2. Stress Erythropoiesis Model Systems.

    Science.gov (United States)

    Bennett, Laura F; Liao, Chang; Paulson, Robert F

    2018-01-01

    Bone marrow steady-state erythropoiesis maintains erythroid homeostasis throughout life. This process constantly generates new erythrocytes to replace the senescent erythrocytes that are removed by macrophages in the spleen. In contrast, anemic or hypoxic stress induces a physiological response designed to increase oxygen delivery to the tissues. Stress erythropoiesis is a key component of this response. It is best understood in mice where it is extramedullary occurring in the adult spleen and liver and in the fetal liver during development. Stress erythropoiesis utilizes progenitor cells and signals that are distinct from bone marrow steady-state erythropoiesis. Because of that observation many genes may play a role in stress erythropoiesis despite having no effect on steady-state erythropoiesis. In this chapter, we will discuss in vivo and in vitro techniques to study stress erythropoiesis in mice and how the in vitro culture system can be extended to study human stress erythropoiesis.

  3. Preschoolers’ Genetic, Physiological, and Behavioral Sensitivity Factors Moderate Links Between Parenting Stress and Child Internalizing, Externalizing, and Sleep Problems

    Science.gov (United States)

    Davis, Molly; Thomassin, Kristel; Bilms, Joanie; Suveg, Cynthia; Shaffer, Anne; Beach, Steven R. H.

    2017-01-01

    This study examined three potential moderators of the relations between maternal parenting stress and preschoolers’ adjustment problems: a genetic polymorphism - the short allele of the serotonin transporter (5-HTTLPR, ss/sl allele) gene, a physiological indicator - children’s baseline respiratory sinus arrhythmia (RSA), and a behavioral indicator - mothers’ reports of children’s negative emotionality. A total of 108 mothers (Mage = 30.68 years, SDage = 6.06) reported on their parenting stress as well as their preschoolers’ (Mage = 3.50 years, SDage = .51, 61% boys) negative emotionality and internalizing, externalizing, and sleep problems. Results indicated that the genetic sensitivity variable functioned according to a differential susceptibility model; however, the results involving physiological and behavioral sensitivity factors were most consistent with a diathesis-stress framework. Implications for prevention and intervention efforts to counter the effects of parenting stress are discussed. PMID:28295263

  4. During stress, heart rate variability moderates the impact of childhood adversity in women with breast cancer.

    Science.gov (United States)

    Tell, Dina; Mathews, Herbert L; Burr, Robert L; Witek Janusek, Linda

    2018-03-01

    Childhood adversity has long-lasting neuro-biological effects that can manifest as exaggerated stress responsivity to environmental challenge. These manifestations include a dysregulated hypothalamic-pituitary-adrenocortical (HPA) axis as well as increased levels of inflammatory mediators in response to stress. In this investigation, vagal parasympathetic activity was assessed for its capacity to moderate the relationship between childhood adversity and stress responsivity (cortisol and inflammation) during an acute laboratory challenge (Trier Social Stress Test-TSST). Thirty women recently diagnosed with breast cancer underwent the TSST during which their heart rate was recorded and saliva samples collected for measurement of cortisol and the proinflammatory cytokine, IL-6. Vagal activity during the TSST was calculated as the high-frequency (HF) component of heart rate variability (HRV). Vagal activity during the TSST moderated the effect of childhood adversity on both the cortisol and the IL-6 response. Women who had lower vagal stress-reactivity during the TSST and reported greater childhood adversity showed a larger rise in cortisol and IL-6 when compared to women with lower childhood adversity. The findings demonstrate that women with exposure to childhood adversity and low vagal stress-reactivity (reduced parasympathetic activity) exhibit an elevated stress response characterized by greater cortisol and proinflammatory cytokine release. Inflammatory burden and HPA dysregulation subsequent to stress may impair cancer control.

  5. Stress and skin disease quality of life: the moderating role of anxiety sensitivity social concerns.

    Science.gov (United States)

    Dixon, L J; Witcraft, S M; McCowan, N K; Brodell, R T

    2018-04-01

    Stress is an important factor in the onset, exacerbation and reoccurrence of many skin diseases. Little is known about psychological risk factors that affect the association between stress and dermatological conditions. One relevant factor that may modulate this link is anxiety sensitivity (AS) social concerns - the propensity to respond fearfully to anxiety-related sensations (e.g. sweating, flushing) owing to perceived social consequences (e.g. rejection or humiliation). To gain insight into psychological factors affecting skin disease, we examined the moderating role of AS social concerns in the relationship between stress and skin disease quality of life (QoL). Participants [n = 237 (161 female), mean ± SD age 34·18 ± 9·57 years] with active skin disease symptoms were recruited online and completed questionnaires assessing stress, AS social concerns, skin disease QoL and global skin disease symptom severity. AS social concerns moderated the association between stress and skin-related emotional and social functioning in adults with skin disease. Stress was a significant predictor of the impairment associated with skin disease. Stress was linked to skin disease-related emotional and functional impairment associated with skin disease among individuals with high AS social concerns. These results highlight the potential for AS reduction interventions to break the vicious cycle of stress and skin disease symptoms and to improve psychosocial well-being in dermatology patients. © 2017 British Association of Dermatologists.

  6. Finding benefits from acculturative stress among Asian Americans: Self-reflection moderating the mediating effects of ethnocultural empathy on positive outcomes.

    Science.gov (United States)

    Wei, Meifen; Li, Chun-I; Wang, Cixin; Ko, Stacy Y

    2016-11-01

    This study examined a moderated mediation model to see whether self-reflection moderated (a) the association between acculturative stress and ethnocultural empathy and (b) the indirect effects of acculturative stress on 2 positive outcomes (i.e., bicultural competence and making positive sense of adversity) through ethnocultural empathy. A total of 330 Asian American college students from a West coast university participated in an online survey. Results from PROCESS supported hypotheses. First, self-reflection significantly moderated the effects of acculturative stress on ethnocultural empathy. Specifically, the effect of acculturative stress on ethnocultural empathy was significantly positive for those with lower self-reflection. Conversely, this effect was not significant for those with higher self-reflection, but ethnocultural empathy was consistently high across all levels of acculturative stress for those with higher self-reflection. Post hoc exploratory analyses examined the moderated mediation model using each of the 5 domains of acculturative stress as predictors; results supported the moderated mediation hypotheses for 2 domains, discrimination and cultural isolation. Second, self-reflection significantly moderated the indirect effects of acculturative stress on 2 positive outcomes through ethnocultural empathy. Results from conditional indirect effects suggested that the indirect effects of acculturative stress on 2 positive outcomes through ethnocultural empathy were significantly positive for those with lower self-reflection. Conversely, the indirect effects were not significant for those with higher self-reflection, but the 2 positive outcomes stayed high at all levels of acculturative stress. Post hoc analyses found that 5 of 6 components of bicultural competence used as outcome variables supported the moderation mediation hypotheses. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  7. Moderate Thermal Stress Causes Active and Immediate Expulsion of Photosynthetically Damaged Zooxanthellae (Symbiodinium from Corals.

    Directory of Open Access Journals (Sweden)

    Lisa Fujise

    Full Text Available The foundation of coral reef biology is the symbiosis between corals and zooxanthellae (dinoflagellate genus Symbiodinium. Recently, coral bleaching, which often results in mass mortality of corals and the collapse of coral reef ecosystems, has become an important issue around the world as coral reefs decrease in number year after year. To understand the mechanisms underlying coral bleaching, we maintained two species of scleractinian corals (Acroporidae in aquaria under non-thermal stress (27°C and moderate thermal stress conditions (30°C, and we compared the numbers and conditions of the expelled Symbiodinium from these corals. Under non-thermal stress conditions corals actively expel a degraded form of Symbiodinium, which are thought to be digested by their host coral. This response was also observed at 30°C. However, while the expulsion rates of Symbiodinium cells remained constant, the proportion of degraded cells significantly increased at 30°C. This result indicates that corals more actively digest and expel damaged Symbiodinium under thermal stress conditions, likely as a mechanism for coping with environmental change. However, the increase in digested Symbiodinium expulsion under thermal stress may not fully keep up with accumulation of the damaged cells. There are more photosynthetically damaged Symbiodinium upon prolonged exposure to thermal stress, and corals release them without digestion to prevent their accumulation. This response may be an adaptive strategy to moderate stress to ensure survival, but the accumulation of damaged Symbiodinium, which causes subsequent coral deterioration, may occur when the response cannot cope with the magnitude or duration of environmental stress, and this might be a possible mechanism underlying coral bleaching during prolonged moderate thermal stress.

  8. Moderate Thermal Stress Causes Active and Immediate Expulsion of Photosynthetically Damaged Zooxanthellae (Symbiodinium) from Corals.

    Science.gov (United States)

    Fujise, Lisa; Yamashita, Hiroshi; Suzuki, Go; Sasaki, Kengo; Liao, Lawrence M; Koike, Kazuhiko

    2014-01-01

    The foundation of coral reef biology is the symbiosis between corals and zooxanthellae (dinoflagellate genus Symbiodinium). Recently, coral bleaching, which often results in mass mortality of corals and the collapse of coral reef ecosystems, has become an important issue around the world as coral reefs decrease in number year after year. To understand the mechanisms underlying coral bleaching, we maintained two species of scleractinian corals (Acroporidae) in aquaria under non-thermal stress (27°C) and moderate thermal stress conditions (30°C), and we compared the numbers and conditions of the expelled Symbiodinium from these corals. Under non-thermal stress conditions corals actively expel a degraded form of Symbiodinium, which are thought to be digested by their host coral. This response was also observed at 30°C. However, while the expulsion rates of Symbiodinium cells remained constant, the proportion of degraded cells significantly increased at 30°C. This result indicates that corals more actively digest and expel damaged Symbiodinium under thermal stress conditions, likely as a mechanism for coping with environmental change. However, the increase in digested Symbiodinium expulsion under thermal stress may not fully keep up with accumulation of the damaged cells. There are more photosynthetically damaged Symbiodinium upon prolonged exposure to thermal stress, and corals release them without digestion to prevent their accumulation. This response may be an adaptive strategy to moderate stress to ensure survival, but the accumulation of damaged Symbiodinium, which causes subsequent coral deterioration, may occur when the response cannot cope with the magnitude or duration of environmental stress, and this might be a possible mechanism underlying coral bleaching during prolonged moderate thermal stress.

  9. Trait Resilience Moderates the Longitudinal Linkage between Adolescent Posttraumatic Stress Disorder Symptoms and Posttraumatic Growth

    Science.gov (United States)

    Ying, Liuhua; Wang, Yanli; Lin, Chongde; Chen, Chuansheng

    2016-01-01

    The current study examined the longitudinal association between posttraumatic stress disorder (PTSD) symptoms and posttraumatic growth (PTG) as well as the moderating role of trait resilience in that association. Participants completed measures of PTSD symptoms, PTG, and trait resilience at 12, 18, and 24 months after the Wenchuan earthquake.…

  10. Moderate water stress affects tomato leaf water relations in dependence on the nitrogen supply

    NARCIS (Netherlands)

    Garcia, A.L.; Marcelis, L.F.M.; Garcia-Sanchez, F.; Nicolas, N.; Martinez, V.

    2007-01-01

    The responses of water relations, stomatal conductance (g(s)) and growth parameters of tomato (Lycopersicon esculentum Mill. cv. Royesta) plants to nitrogen fertilisation and drought were studied. The plants were subjected to a long-term, moderate and progressive water stress by adding 80 % of the

  11. For Whom Does Mindfulness-Based Stress Reduction Work? : Moderating Effects of Personality

    NARCIS (Netherlands)

    Nyklíček, Ivan; Irrmischer, Mona

    2017-01-01

    The aim of the present study was to examine potentially moderating effects of personality characteristics regarding changes in anxious and depressed mood associated with Mindfulness-Based Stress Reduction (MBSR), controlling for socio-demographic factors. Meditation-naïve participants from the

  12. Family Roles as Moderators of the Relationship between Schedule Flexibility and Stress

    Science.gov (United States)

    Jang, Soo Jung; Zippay, Allison; Park, Rhokeun

    2012-01-01

    Employer initiatives that address the spillover of work strain onto family life include flexible work schedules. This study explored the mediating role of negative work-family spillover in the relationship between schedule flexibility and employee stress and the moderating roles of gender, family workload, and single-parent status. Data were drawn…

  13. Predictors and moderators of biopsychological social stress responses following brief self-compassion meditation training.

    Science.gov (United States)

    Arch, Joanna J; Landy, Lauren N; Brown, Kirk Warren

    2016-07-01

    Arch et al. (2014) demonstrated that brief self-compassion meditation training (SCT) dampened sympathetic (salivary alpha-amylase) and subjective anxiety responses to the Trier Social Stress Test (TSST), relative to attention and no-instruction control conditions. The present study examined baseline predictors and moderators of these SCT intervention effects. Baseline characteristics included two stress vulnerability traits (social anxiety and rumination) and two potential resiliency traits (non-attachment and self-compassion). We investigated how these traits moderated the effects of SCT on response to the TSST, relative to the control conditions. We also tested how these individual differences predicted TSST responses across conditions in order to uncover characteristics that confer increased vulnerability and resiliency to social stressors. Trait non-attachment, rumination (for sympathetic TSST response only), and social anxiety (for subjective TSST response only) interacted with training condition to moderate TSST responses such that following SCT, lower attachment and lower social anxiety predicted lower TSST stress responses, relative to those scoring higher on these traits. In contrast, trait self-compassion neither moderated nor predicted responses to the TSST. Thus, although SCT had robust effects on buffering stress across individuals with varying levels of trait self-compassion, other psychological traits enhanced or dampened the effect of SCT on TSST responses. These findings support the importance of examining the role of relevant baseline psychological traits to predict sympathetic and subjective responses to social evaluative threat, particularly in the context of resiliency training. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Profiles of Observed Infant Anger Predict Preschool Behavior Problems: Moderation by Life Stress

    Science.gov (United States)

    Brooker, Rebecca J.; Buss, Kristin A.; Lemery-Chalfant, Kathryn; Aksan, Nazan; Davidson, Richard J.; Goldsmith, H. Hill

    2014-01-01

    Using both traditional composites and novel profiles of anger, we examined associations between infant anger and preschool behavior problems in a large, longitudinal data set (N = 966). We also tested the role of life stress as a moderator of the link between early anger and the development of behavior problems. Although traditional measures of…

  15. Developing models of how cognitive improvements change functioning: Mediation, moderation and moderated mediation

    Science.gov (United States)

    Wykes, Til; Reeder, Clare; Huddy, Vyv; Taylor, Rumina; Wood, Helen; Ghirasim, Natalia; Kontis, Dimitrios; Landau, Sabine

    2012-01-01

    Background Cognitive remediation (CRT) affects functioning but the extent and type of cognitive improvements necessary are unknown. Aim To develop and test models of how cognitive improvement transfers to work behaviour using the data from a current service. Method Participants (N49) with a support worker and a paid or voluntary job were offered CRT in a Phase 2 single group design with three assessments: baseline, post therapy and follow-up. Working memory, cognitive flexibility, planning and work outcomes were assessed. Results Three models were tested (mediation — cognitive improvements drive functioning improvement; moderation — post treatment cognitive level affects the impact of CRT on functioning; moderated mediation — cognition drives functioning improvements only after a certain level is achieved). There was evidence of mediation (planning improvement associated with improved work quality). There was no evidence that cognitive flexibility (total Wisconsin Card Sorting Test errors) and working memory (Wechsler Adult Intelligence Scale III digit span) mediated work functioning despite significant effects. There was some evidence of moderated mediation for planning improvement if participants had poorer memory and/or made fewer WCST errors. The total CRT effect on work quality was d = 0.55, but the indirect (planning-mediated CRT effect) was d = 0.082 Conclusion Planning improvements led to better work quality but only accounted for a small proportion of the total effect on work outcome. Other specific and non-specific effects of CRT and the work programme are likely to account for some of the remaining effect. This is the first time complex models have been tested and future Phase 3 studies need to further test mediation and moderated mediation models. PMID:22503640

  16. Emotional intelligence as a moderator in the stress-burnout relationship: a questionnaire study on nurses.

    Science.gov (United States)

    Görgens-Ekermans, Gina; Brand, Tamari

    2012-08-01

    To investigate inter-relationships between emotional intelligence (EI), work stress and burnout in a group of nurses in the Western Cape Province, South Africa. The moderating effect of EI in the stress-burnout relationship and group differences (nurses working in different wards) in burnout were also investigated. Stress and subsequent burnout commonly threaten the occupational health and well-being of nurses in South Africa and elsewhere. Developing EI in nurses may increase individual stress resistance and combat burnout. A cross-sectional research design with anonymous questionnaires was conducted. Self-report data were used. Survey data were collected from 122 nurses working in different wards at four hospitals from a private hospital group. The Swinburne University Emotional Intelligence Test, Sources of Work Stress Inventory and Maslach Burnout Inventory were used to measure EI, stress and burnout, respectively. Consistent inverse relationships between emotional control and management as dimensions of EI, and stress and burnout emerged. A differential effect of high vs. low EI on the stress-burnout relationship was evident. Workload and the work/family interface emerged as significant predictors of burnout. Respondents working in maternity, paediatric and ER wards reported more feelings of personal accomplishment than those working in general wards. Higher EI is significantly related with lower stress and burnout in a sample of South African nurses. The moderator effect of EI in the stress-burnout relationship suggests that enhanced EI may help diminish burnout development when chronic stress is experienced. EI developmental interventions, if introduced in nursing curricula, may increase emotional coping resources and enhanced social skills, which may benefit the long-term occupational health of nurses. This may be relevant in developing countries, where environmental stressors related to the organisational context (budget constraints) and wider social

  17. Stress and multiple sclerosis: A systematic review considering potential moderating and mediating factors and methods of assessing stress.

    Science.gov (United States)

    Briones-Buixassa, Laia; Milà, Raimon; Mª Aragonès, Josep; Bufill, Enric; Olaya, Beatriz; Arrufat, Francesc Xavier

    2015-07-01

    Research about the effects of stress on multiple sclerosis has yielded contradictory results. This study aims to systematically review the evidence focusing on two possible causes: the role of stress assessment and potential moderating and mediating factors. The Web of Knowledge (MEDLINE and Web of Science), Scopus, and PsycINFO databases were searched for relevant articles published from 1900 through December 2014 using the terms "stress*" AND "multiple sclerosis." Twenty-three articles were included. Studies focused on the effect of stress on multiple sclerosis onset ( n  = 9) were mostly retrospective, and semi-structured interviews and scales yielded the most consistent associations. Studies focused on multiple sclerosis progression ( n  = 14) were mostly prospective, and self-reported diaries yielded the most consistent results. The most important modifying factors were stressor duration, severity, and frequency; cardiovascular reactivity and heart rate; and social support and escitalopram intake. Future studies should consider the use of prospective design with self-reported evaluations and the study of moderators and mediators related to amount of stress and autonomic nervous system reactivity to determine the effects of stress on multiple sclerosis.

  18. Stress and multiple sclerosis: A systematic review considering potential moderating and mediating factors and methods of assessing stress

    Directory of Open Access Journals (Sweden)

    Laia Briones-Buixassa

    2015-11-01

    Full Text Available Research about the effects of stress on multiple sclerosis has yielded contradictory results. This study aims to systematically review the evidence focusing on two possible causes: the role of stress assessment and potential moderating and mediating factors. The Web of Knowledge (MEDLINE and Web of Science, Scopus, and PsycINFO databases were searched for relevant articles published from 1900 through December 2014 using the terms “stress*” AND “multiple sclerosis.” Twenty-three articles were included. Studies focused on the effect of stress on multiple sclerosis onset ( n  = 9 were mostly retrospective, and semi-structured interviews and scales yielded the most consistent associations. Studies focused on multiple sclerosis progression ( n  = 14 were mostly prospective, and self-reported diaries yielded the most consistent results. The most important modifying factors were stressor duration, severity, and frequency; cardiovascular reactivity and heart rate; and social support and escitalopram intake. Future studies should consider the use of prospective design with self-reported evaluations and the study of moderators and mediators related to amount of stress and autonomic nervous system reactivity to determine the effects of stress on multiple sclerosis.

  19. Mediation and Moderation of the Relationship Between Combat Experiences and Post-Traumatic Stress Symptoms in Active Duty Military Personnel.

    Science.gov (United States)

    Steele, Marshall; Germain, Anne; Campbell, Justin S

    2017-05-01

    Post-traumatic stress disorder (PTSD) is a major health concern among the U.S. military population, affecting up to 12% to 24% of veterans returning from Iraq and Afghanistan. Sleep disturbances, neuroticism, and childhood trauma have all been associated with the development of PTSD in military populations, especially in relation to combat experiences. The effects of disrupted sleep and post-traumatic stress can affect the physical well-being of soldier and sailors in the field and impact them for years after deployment. This study aimed to evaluate the relationship between self-reported measures of combat experiences, PTSD symptoms, sleep, neuroticism, and childhood adversity in an active duty military population. 972 U.S. Navy Sailors serving in Afghanistan were given anonymous surveys that assess scales of combat stressors, PTSD symptoms, sleep problems, neuroticism, adverse child experiences (ACEs), and other covariates. Sleep disturbances were hypothesized as moderators, having an indirect effect on the relationship between combat experiences and PTSD symptoms. Neuroticism scores and ACEs were proposed as moderators of the combat-PTSD symptom relationship. Mediation and moderation models were developed and tested using logistic regressions. Increased number of combat experiences was found to be a significant predictor of PTSD, even when adjusting for all covariates (p moderating factor. These results indicate that the presence of nightmares may partially explain how traumatic combat experiences lead to the development of PTSD. The study also reaffirms neuroticism as risk factor for developing PTSD symptoms. These findings highlight the importance of sleep hygiene and operational stress models in combat situations and may help stress control professionals address risk factors associated with PTSD symptoms. Reprint & Copyright © 2017 Association of Military Surgeons of the U.S.

  20. Moderate alcohol consumption after a mental stressor attenuates the endocrine stress response.

    Science.gov (United States)

    Schrieks, I C; Joosten, M M; Klöpping-Ketelaars, W A A; Witkamp, R F; Hendriks, H F J

    2016-12-01

    Alcohol is often consumed to reduce tension and improve mood when exposed to stressful situations. Previous studies showed that moderate alcohol consumption may reduce stress when alcohol is consumed prior to a stressor, but data on the effect of alcohol consumption after a mental stressor is limited. Therefore, our objective was to study whether moderate alcohol consumption immediately after a mental stressor attenuates the stress response. Twenty-four healthy men (age 21-40 y, BMI 18-27 kg/m 2 ) participated in a placebo-controlled trial. They randomly consumed 2 cans (660 mL, ∼26 g alcohol) of beer or alcohol-free beer immediately after a mental stressor (Stroop task and Trier Social Stress Test). Physiological and immunological stress response was measured by monitoring heart rate and repeated measures of the hypothalamic-pituitary-adrenal axis (HPA-axis), white blood cells and a set of cytokines. After a mental stressor, cortisol and adrenocorticotropic hormone (ACTH) concentrations were 100% and 176% more reduced at 60 min (P = 0.012 and P = 0.001, respectively) and 92% and 60% more reduced at 90 min (P stress recovery period after beer consumption than after alcohol-free beer consumption (P stress response as reflected by decreasing plasma ACTH and cortisol. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. The moderator role of emotion regulation ability in the link between stress and well-being

    Directory of Open Access Journals (Sweden)

    Natalio eExtremera

    2015-10-01

    Full Text Available This article examined the moderating role of a central core dimension of emotional intelligence – emotion-regulation ability – in the relationship between perceived stress and indicators of well-being (depression and subjective happiness in a sample from a community adult population. The relationships for males and females on these dimensions were also compared. Results revealed that emotion-regulation abilities moderated both the association between perceived stress and depression/happiness for the total sample. However, a gender-specific analysis showed that the moderation effect was only significant for males. In short, when males reported a high level of perceived stress, those with high scores in regulating emotions reported higher scores in subjective happiness and lower depression symptoms than those with low regulating emotions. However, no interaction effect of regulating emotions and stress for predicting subjective happiness and depression was found for females. In developing stress management programmes for reducing depression and increasing well-being, these findings suggest that training in emotional regulation may be more beneficial for males than females. Our findings are discussed in terms of the need for future research to understand the different gender associations and to consider these differences in further intervention programmes.

  2. PENGARUH KOMITMEN ORGANISASI DAN KOMITMEN PROFESIONALTERHADAP KEPUASAN KERJA AKUNTAN PUBLIK:ROLE STRESS SEBAGAI VARIABEL MODERATING

    Directory of Open Access Journals (Sweden)

    R. Ardi Agung Heriawan

    2016-02-01

    Full Text Available The purpose of this research is to analyzed the influence of organizational commitment, professional commitment to job satisfaction of public accountants with a role stress as moderating variable. The samples of this research are 44 public accountants that worked at public accountants office which registered in Yogyakarta and Semarang. The data were analyzed by multiple regression method with moderating variable.The result of this analysis of individual test show that role conflict is not moderated of relation by organizational commitment with job satisfaction. Also with role ambiguity which not moderated or relation by organizational commitment with job satisfaction. The main practical implication of this research is that the public accountants organizational must be attention to jobs expectation of their auditors. Because that is the factors that rising the organizational commitment and in the future it will be to give a high school satisfaction.

  3. A General Model for Testing Mediation and Moderation Effects

    Science.gov (United States)

    MacKinnon, David P.

    2010-01-01

    This paper describes methods for testing mediation and moderation effects in a dataset, both together and separately. Investigations of this kind are especially valuable in prevention research to obtain information on the process by which a program achieves its effects and whether the program is effective for subgroups of individuals. A general model that simultaneously estimates mediation and moderation effects is presented, and the utility of combining the effects into a single model is described. Possible effects of interest in the model are explained, as are statistical methods to assess these effects. The methods are further illustrated in a hypothetical prevention program example. PMID:19003535

  4. Sociotropic cognition moderates stress-induced cardiovascular responsiveness in college women.

    Science.gov (United States)

    Sauro, M D; Jorgensen, R S; Larson, C A; Frankowski, J J; Ewart, C K; White, J

    2001-10-01

    This study examined the moderating effects of sociotropic cognition (SC), a nondefensive need for approval, on stress-induced cardiovascular responsiveness (CVR) in women. Sixty-seven college-age females had blood pressure (BP) and heart rate (HR) monitored during baseline, anticipation, story-telling (where participants were randomly assigned to a low or high threat condition), and recovery periods. SC showed a positive association with CVR only in the high interpersonal threat context during task and early stages of the recovery periods. SC was positively correlated with such variables as anxiety, ruminative style, dysphoria, and anger. This is the first report examining the moderating effects of SC on interpersonal stress-induced CVR prior to, during, and following a task, using an explicit manipulation of social evaluation. The data help define risk factors for CVR in women, which may aid in the understanding of how emotions and stress affect physical health and well-being.

  5. Work stress and alcohol consumption among adolescents: moderation by family and peer influences.

    Science.gov (United States)

    Liu, Xianfang C; Keyes, Katherine M; Li, Guohua

    2014-12-18

    Excessive alcohol use in adolescence can be detrimental to health and academic performance. Few studies consider the moderating effects of parental and peer influence within the context of adolescent work outside of the school environment. This study aims to examine work stress among adolescents and the association with alcohol use and drunkenness, in the context of parental and peer influences. Grade 12 students who participated in Monitoring the Future surveys between 2005 and 2009 (n = 12,341) were included in this study. Independent variables included work stress (job satisfaction, perceived safety, and perceived safety of possessions), self-reported perceptions towards academics and influence from parents and peers. Frequency of alcohol use and drunkenness were measured for lifetime, last 30 days and 12 months. The moderating effects of academic aspiration, parental, and peer influence were assessed on the relationship between work stress and alcohol use. Any work stress was positively associated with alcohol use over the past 12 months (odds ratio = 1.12, 95% confidence interval (CI) 1.02-1.23). Stratified analysis found that peer influence significantly moderated the relationship between work stress and alcohol use over the lifetime and past 12 months. Among adolescents with work stress, odds ratios of alcohol use over the lifetime was 0.83 (95% CI 0.71-0.97) for those with low negative peer influence and 1.09 (95% CI 0.97-1.22) for those with high negative peer influence. Problematic drinking patterns were more apparent among high school students who experienced stress at work. Positive peer influence, however, may buffer the adverse effect of work stress on alcohol use.

  6. The 5-HTTLPR polymorphism moderates the effect of stressful life events on drinking behavior in college students of African descent.

    Science.gov (United States)

    Kranzler, Henry R; Scott, Denise; Tennen, Howard; Feinn, Richard; Williams, Carla; Armeli, Stephen; Taylor, Robert E; Briggs-Gowan, Margaret J; Covault, Jonathan

    2012-07-01

    Covault et al. [Covault et al. (2007); Biol Psychiatry 61(5): 609-616] reported that the common functional polymorphism, 5-HTTLPR, in the serotonin transporter gene moderated the association between past-year stressful events and daily reports of drinking in a sample of European-American (EA) college students. We examined this effect in college students of African descent. Students recruited at a Historically Black University (n = 564) completed web-based measures of past-year stressful life experiences and daily reports of drinking and heavy drinking over a 30-day period. Participants were genotyped for the tri-allelic 5-HTTLPR polymorphism and dichotomized as low-activity S' allele carriers or high-activity L' homozygotes. Generalized linear models were used to examine the effects of life stress, genotype, and their interaction on the two drinking measures. In students who completed 15 or more daily surveys (n = 393), there was a significant interaction of past-year stressful events, 5-HTTLPR genotype, and gender on the number of drinking days (P = 0.002). Similar findings were obtained in relation to heavy drinking days (P = 0.007). Men showed a main effect of past-year stressful events on both drinking outcomes (P's life stressors on the frequency of drinking and heavy drinking days (P's stressful events were associated with more frequent drinking and heavy drinking, an effect that was moderated by the 5-HTTLPR polymorphism. However, in contrast to the findings in EA students, in the current sample, 5-HTTLPR moderated the association only among women. Copyright © 2012 Wiley Periodicals, Inc.

  7. A Mediated Moderation Model of Conformative Peer Bullying

    Science.gov (United States)

    Cho, Yoonju; Chung, Ock-Boon

    2012-01-01

    We investigated the relationship between conformative peer bullying and issues of peer conformity among adolescents. This relationship is examined through the establishment of a mediated moderation model for conformative peer bullying using structural equation modeling in a sample of 391 second-year middle school students in Seoul, South Korea. We…

  8. Modeling of high speed micro rotors in moderate flow confinement

    NARCIS (Netherlands)

    Dikmen, E.; van der Hoogt, Peter; Aarts, Ronald G.K.M.; Sas, P.; Bergen, B.

    2008-01-01

    The recent developments in high speed micro rotating machinery lead to the need for multiphysical modeling of the rotor and the surrounding medium. In this study, thermal and flow induced effects on rotor dynamics of geometries with moderate flow confinement are studied. The structure is modeled via

  9. Contingent self-worth moderates the relationship between school stressors and psychological stress responses.

    Science.gov (United States)

    Ishizu, Kenichiro

    2017-04-01

    This study examined the moderating role of contingent self-worth on the relationships between school stressors and psychological stress responses among Japanese adolescents. A total of 371 Japanese junior high school students (184 boys and 187 girls, M age  = 12.79 years, SD = 0.71) completed the Japanese version of the Self-Worth Contingency Questionnaire and a mental health checklist at two points separated by a two-month interval. Hierarchical multiple regression analyses were then used to determine whether contingent self-worth moderated the relationship between school stressors and psychological stress responses. The results indicated that, when psychological stress responses were controlled for at Time 1, contingent self-worth did not predict the psychological stress responses at Time 2. However, a two-way interaction between contingent self-worth and stressors was found to significantly influence psychological stress responses, thus indicating that stressors had a stronger impact on psychological stress responses among those with high contingent self-worth compared to those with low contingent self-worth. Copyright © 2017 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

  10. Does Organizational and Coworker Support Moderate Diabetes Risk and Job Stress Among Employees?

    Science.gov (United States)

    Wolff, Marilyn B; Gay, Jennifer L; Wilson, Mark G; DeJoy, David M; Vandenberg, Robert J

    2018-05-01

    Examine the moderating role of perceived organizational and coworker support on the relationship between job stress and type 2 diabetes risk among employees. A cross-sectional survey was administered to employees at the workplace. One national retail organization. Baseline data were obtained from 1595 employees in 21 retail stores. Self-reported organizational and coworker support to encourage and fulfill job responsibilities and job stress. Diabetes risk was calculated using age, gender, race/ethnicity, blood pressure, physical activity, weight status, and self-reported diagnosed type 2 diabetes. Multilevel multiple regression was conducted to test the interaction effect of support on the association between job stress and diabetes risk. Mean age was 37.95 years (±12.03) and body mass index was 26.72 (±4.95). Three percent of participants reported diagnosed diabetes. Organizational support was positively associated with coworker support. Both were negatively associated with job stress. Organizational support, but not coworker support, moderated the relationship of job stress with diabetes risk. Participants with greater perceived organizational support had lower diabetes risk scores compared to those with lower perceived organizational support. Organizational support may be a key factor for workplaces to reduce stress and diabetes risk. Further testing of organizations' supportive role on employee health may be helpful in developing future workplace programs.

  11. Moderate altitude but not additional endurance training increases markers of oxidative stress in exhaled breath condensate.

    Science.gov (United States)

    Heinicke, Ilmar; Boehler, Annette; Rechsteiner, Thomas; Bogdanova, Anna; Jelkmann, Wolfgang; Hofer, Markus; Rawlings, Pablo; Araneda, Oscar F; Behn, Claus; Gassmann, Max; Heinicke, Katja

    2009-07-01

    Oxidative stress occurs at altitude, and physical exertion might enhance this stress. In the present study, we investigated the combined effects of exercise and moderate altitude on redox balance in ten endurance exercising biathletes, and five sedentary volunteers during a 6-week-stay at 2,800 m. As a marker for oxidative stress, hydrogen peroxide (H(2)O(2)) was analyzed by the biosensor measuring system Ecocheck, and 8-iso prostaglandin F2alpha (8-iso PGF2alpha) was determined by enzyme immunoassay in exhaled breath condensate (EBC). To determine the whole blood antioxidative capacity, we measured reduced glutathione (GSH) enzymatically using Ellman's reagent. Exercising athletes and sedentary volunteers showed increased levels of oxidative markers at moderate altitude, contrary to our expectations; there was no difference between both groups. Therefore, all subjects' data were pooled to examine the oxidative stress response exclusively due to altitude exposure. H(2)O(2) levels increased at altitude and remained elevated for 3 days after returning to sea level (p altitude, but declined immediately after returning to sea level (p altitude resulted in elevated GSH levels (p altitude (p altitude for up to 6 weeks increases markers of oxidative stress in EBC independent of additional endurance training. Notably, this oxidative stress is still detectable 3 days upon return to sea level.

  12. Occupational Stress and Mental Health Symptoms: Examining the Moderating Effect of Work Recovery Strategies in Firefighters.

    Science.gov (United States)

    Sawhney, Gargi; Jennings, Kristen S; Britt, Thomas W; Sliter, Michael T

    2017-06-12

    The goal of this research was to examine the moderating effect of work recovery strategies on the relationship between occupational stress experienced by firefighters and mental health symptoms. Work recovery strategies were identified through semistructured interviews with 20 firefighters and a literature search on recovery strategies. A total of 7 work recovery strategies emerged using the 2 methods: work-related talks, stress-related talks, time with coworkers/supervisor, exercise, recreational activities, relaxation, and mastery experiences. Using a prospective study design with a 1-month time interval in a sample of 268 firefighters, experienced occupational stress at Time 1 was positively related to mental health symptoms at Time 2. In addition, with the exception of spending time with coworkers/supervisor, exercise and mastery experiences, recovery strategies at Time 1 were negatively related to mental health symptoms at Time 2. Lastly, all work recovery strategies, except stress-related talks and relaxation, moderated the relationship between experienced occupational stress at Time 1 and mental health symptoms at Time 2. Specifically, the positive relationship between experienced occupational stress and mental health symptoms was stronger when firefighters engaged in low, rather than high, work recovery strategies. Implications for research and practice are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  13. Mediating and moderating effects of work-home interference upon farm stresses and psychological distress.

    Science.gov (United States)

    McShane, Connar Jo; Quirk, Frances

    2009-10-01

    This study investigated whether work-home (WHI) or home-work interference (HWI) explained or affected the strength of the relationship between farmers' stresses and reported psychological distress. Distribution of questionnaire package; included Work-Home Conflict Scale, Farm Stress Survey, Depression Anxiety Stress Scale. Participants recruited via advertising in newsletters and newspapers, and distribution through businesses and meetings. The majority of farmers (N = 51, male = 45, female = 5) were recruited from the one district. Farmers were individuals who identified their occupation as a farm owner, farm manager, or farm hand. It was predicted farmers would report higher levels of WHI than HWI; time, a determinant of interference, would mediate the relationship between farmers' stresses and psychological distress; WHI and HWI would moderate farmers' stresses and their psychological distress; overall reported level of psychological distress would be in normal to mild range because of positive general economic conditions. Farmers reported significantly higher levels of WHI than HWI (M = 3.21, M = 2.76, P stresses and psychological distress, particularly anxiety. WHI, time and strain, determinants of WHI mediated personal finances and subcomponents of psychological distress (stress, anxiety, depression). Time-based HWI mediated personal finances and stress. No moderating effects were found for WHI (r = -0.02, P = 0.882) or HWI (r = 0.15, P = 0.306). Farmers of this specific sample presented a unique work-home interface. Limitations include the small sample size, recruitment methods, and culturally irrelevant measures as well as only assessing work-related stresses. Future research should aim to develop measures appropriate for farmers of Australia.

  14. Cognitive Moderators of Children's Adjustment to Stressful Divorce Events: The Role of Negative Cognitive Errors and Positive Illusions.

    Science.gov (United States)

    Mazur, Elizabeth; Wolchik, Sharlene A.; Virdin, Lynn; Sandler, Irwin N.; West, Stephen G.

    1999-01-01

    Examined whether children's cognitive biases moderated impact of stressful divorce-related events on adjustment in 9- to 12-year olds. Found that endorsing negative cognitive errors for hypothetical divorce events moderated relations between stressful divorce events and self- and maternal-reports of internalizing and externalizing symptoms for…

  15. Psychosocial Pain Management Moderation: The Limit, Activate, and Enhance Model.

    Science.gov (United States)

    Day, Melissa A; Ehde, Dawn M; Jensen, Mark P

    2015-10-01

    There is a growing emphasis in the pain literature on understanding the following second-order research questions: Why do psychosocial pain treatments work? For whom do various treatments work? This critical review summarizes research that addresses the latter question and proposes a moderation model to help guide future research. A theoretical moderation framework for matching individuals to specific psychosocial pain interventions has been lacking. However, several such frameworks have been proposed in the broad psychotherapy and implementation science literature. Drawing on these theories and adapting them specifically for psychosocial pain treatment, here we propose a Limit, Activate, and Enhance model of pain treatment moderation. This model is unique in that it includes algorithms not only for matching treatments on the basis of patient weaknesses but also for directing patients to interventions that build on their strengths. Critically, this model provides a basis for specific a priori hypothesis generation, and a selection of the possible hypotheses drawn from the model are proposed and discussed. Future research considerations are presented that could refine and expand the model based on theoretically driven empirical evidence. The Limit, Activate, and Enhance model presented here is a theoretically derived framework that provides an a priori basis for hypothesis generation regarding psychosocial pain treatment moderators. The model will advance moderation research via its unique focus on matching patients to specific treatments that (1) limit maladaptive responses, (2) activate adaptive responses, and (3) enhance treatment outcomes based on patient strengths and resources. Copyright © 2015 American Pain Society. Published by Elsevier Inc. All rights reserved.

  16. A Model of Teacher Stress

    Science.gov (United States)

    Kyriacou, Chris; Sutcliffe, John

    1978-01-01

    A definition and model of teacher stress is presented which conceptualizes teacher stress as a response syndrome (anger or depression) mediated by (1) an appraisal of threat to the teacher's self-esteem or well-being and (2) coping mechanisms activated to reduce the perceived threat. (Author)

  17. Stressful Life Events: Moderators of the Relationships of Gender and Gender Roles to Self-Reported Depression and Suicidality among College Students.

    Science.gov (United States)

    Waelde, Lynn C.; And Others

    1994-01-01

    Examines whether relationships of self-reported depression and suicidality to gender roles or gender are moderated by stressful life events. Results with 290 female and 247 male undergraduates support the androgyny model of adjustment and a self-schema model of depression. (SLD)

  18. Moderate Level Alcohol During Pregnancy, Prenatal Stress, or Both and Limbic-Hypothalamic-Pituitary-Adrenocortical Axis Response to Stress in Rhesus Monkeys

    Science.gov (United States)

    Schneider, Mary L.; Moore, Colleen F.; Kraemer, Gary W.

    2004-01-01

    This study examined the relationship between moderate-level prenatal alcohol exposure, prenatal stress, and postnatal response to a challenging event in 6-month-old rhesus monkeys. Forty-one rhesus monkey (Macaca mulatta) infants were exposed prenatally to moderate level alcohol, maternal stress, or both. Offspring plasma cortisol and…

  19. Linking perceptions of role stress and incivility to workplace aggression: the moderating role of personality.

    Science.gov (United States)

    Taylor, Shannon G; Kluemper, Donald H

    2012-07-01

    Although research on workplace aggression has long recognized job stressors as antecedents, little is known about the process through which employee responses to stressful workplace demands escalate from relatively mild interactions into more intense behaviors. This study investigates the influence that employees' perceptions of role stress (ambiguity, conflict, overload) have on their aggressive behavior by affecting their perceptions of incivility, and whether these downstream effects depend on personality traits (neuroticism, agreeableness, conscientiousness). Results supported moderated mediation, such that the indirect effects of perceived role ambiguity and role conflict on enacted aggression through experienced incivility varied according to individual differences in personality.

  20. Use of e-Learning for Stress management – Multi-group moderation analysis

    OpenAIRE

    Aamir Sarwar; Chitapa Ketavan; Nadeem Shafique Butt

    2016-01-01

    The goal of this study is to find out the moderating role of type of industry and different levels of management with respect to eLearning perception, eLearning advantages and use of eLearning for Stress Management. Study tried to find out relationship between perceptions of eLearning, eLearning Advantages, perception of using eLearning for corporate training and more specifically for stress management. A cross sectional survey is conducted through structured questionnaire to collect the data...

  1. Differential sensitization of parenting on early adolescent cortisol: Moderation by profiles of maternal stress.

    Science.gov (United States)

    Martin, Christina Gamache; Kim, Hyoun K; Fisher, Philip A

    2016-05-01

    The hypothalamic-pituitary-adrenal (HPA) axis is a critical component of the body's stress-response neurobiological system, and its development and functioning are shaped by the social environment. Much of our understanding of the effects of the caregiving environment on the HPA axis is based on (a) parenting in young children and (b) individual maternal stressors, such as depression. Yet, less is known about how parenting behaviors and maternal stressors interact to influence child cortisol regulation, particularly in older children. With an ethnically diverse sample of 199 mothers and their early adolescent children (M=11.00years; 54% female), a profile analytic approach was used to investigate how multiple phenotypes of maternal stress co-occur and moderate the relation between parenting behaviors and youths' diurnal cortisol rhythms. Latent profile analysis yielded 4 profiles: current parenting stress, concurrent parenting and childhood stress, childhood stress, and low stress. For mothers with the concurrent parenting and childhood stress profile, inconsistent discipline, poor parental supervision, and harsh caregiving behaviors each were related to flattened diurnal cortisol rhythms in their adolescents. For mothers with the current parenting stress and childhood stress profiles, their use of inconsistent discipline was associated with flattened diurnal cortisol rhythms in their adolescents. For mothers with the low stress profile, none of the parenting behaviors was related to their adolescents' cortisol regulation. Findings suggest that based on mothers' stress profile, parenting behaviors are differentially related to youths' diurnal cortisol rhythms. Implications for parenting interventions are discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. For Whom Does Mindfulness-Based Stress Reduction Work? Moderating Effects of Personality.

    Science.gov (United States)

    Nyklíček, Ivan; Irrmischer, Mona

    2017-01-01

    The aim of the present study was to examine potentially moderating effects of personality characteristics regarding changes in anxious and depressed mood associated with Mindfulness-Based Stress Reduction (MBSR), controlling for socio-demographic factors. Meditation-naïve participants from the general population self-presenting with psychological stress complaints ( n  = 167 participants, 70% women, mean age 45.8 ± 9.3 years) were assessed in a longitudinal investigation of change in mood before and after the intervention and at a 3-month follow-up. Participants initially scoring high on neuroticism showed stronger decreases in both anxious and depressed mood (both p  moderating effects, when controlled for baseline mood. Only neuroticism showed to be associated with delayed benefit. Results are discussed in the context of findings from similar research using more traditional cognitive-behavioral interventions.

  3. Water Stress Projection Modeling

    Science.gov (United States)

    2016-09-01

    water consumption stress in coming decades is electricity generation in two surrounding counties, El Paso and Doña Ana, which are expected to...better able to predict and prepare for a changing climate. Army installations will be affected by climate change. It behooves the Army to understand...stationing analysis, the resources ex- amined were: a. Training land b. Energy ( electricity and natural gas) c. Water and wastewater treatment and solid

  4. Encouraging moderation: clues from a simple model of ideological conflict.

    Science.gov (United States)

    Marvel, Seth A; Hong, Hyunsuk; Papush, Anna; Strogatz, Steven H

    2012-09-14

    Some of the most pivotal moments in intellectual history occur when a new ideology sweeps through a society, supplanting an established system of beliefs in a rapid revolution of thought. Yet in many cases the new ideology is as extreme as the old. Why is it then that moderate positions so rarely prevail? Here, in the context of a simple model of opinion spreading, we test seven plausible strategies for deradicalizing a society and find that only one of them significantly expands the moderate subpopulation without risking its extinction in the process.

  5. "Don't crack under pressure!"--Do leisure time physical activity and self-esteem moderate the relationship between school-based stress and psychosomatic complaints?

    Science.gov (United States)

    Gerber, Markus; Pühse, Uwe

    2008-10-01

    Stressful experiences occupy a central role in most etiological models of developmental psychopathology. Stress alone, however, insufficiently explains negative health outcomes. This raises the question why some children and adolescents are more vulnerable to the development of psychopathological symptoms than others. The primary purpose of this research was to demonstrate whether leisure time physical activity and self-esteem protect against stress-induced health problems. The findings are based on a cross-sectional study of 407 Swiss boys and girls (M=14.01 years). All variables are self-reported. Analyses of covariance were applied to test for main and moderator effects. The findings suggest that school-based stress and psychosomatic complaints are important issues during adolescence. The results show that a higher level of psychosomatic complaints accompanies stress. Surprisingly, psychosomatic complaints and physical activity were unrelated. Likewise, no association was found between physical activity and stress. In contrast, students with high self-esteem reported significantly less complaints and a lower extent of perceived stress. Finally, the results do not support the stress-moderation hypothesis. Neither physical activity nor self-esteem buffered against the detrimental effects of school-based stress on psychosomatic health. The findings lend support to previous research with German-speaking samples but are in marked contrast to Anglo-Saxon studies, which generally support the role of physical activity as a moderator of the health-illness relationship. In this investigation, developmental features and methodological limitations may have accounted for the insignificant results.

  6. Social Support Moderates the Relationship Between Perceived Stress and Quality of Life in Patients With a Left Ventricular Assist Device.

    Science.gov (United States)

    Abshire, Martha; Russell, Stuart D; Davidson, Patricia M; Budhathoki, Chakra; Han, Hae-Ra; Grady, Kathleen L; Desai, Shashank; Dennison Himmelfarb, Cheryl

    2018-04-20

    Living with a left ventricular assist device has significant psychosocial sequelae that affect health-related quality of life (HRQOL). The purpose of this study was to (1) describe psychosocial indicators of stress including perceived stress, depression, fatigue, and coping; (2) examine relationships among stress indicators by level of perceived stress; (3) examine relationships among indicators of stress and clinical outcomes; and (4) test the moderation of social support on the relationship between stress and clinical outcomes. Participants were recruited from 2 outpatient clinics in a cross-sectional study design. Standardized measures were self-administered via survey. Descriptive statistics, correlation, and multiple linear regression analysis were conducted. The sample (N = 62) was mostly male (78%), black (47%), and married (66%), with a mean age of 56.5 ± 13 years. The overall sample had a moderate stress profile: moderate perceived stress (mean, 11.7 ± 7), few depressive symptoms (mean, 3.2 ± 3.9), and moderate fatigue (mean, 14.3 ± 9.1). Increased perceived stress was associated with fatigue, depressive symptoms, and maladaptive coping (P stress and fatigue were significant correlates of overall HRQOL (adj. R = 0.41, P relationship between perceived stress and HRQOL, controlling for fatigue (R = 0.49, P stress have worse depressive symptoms, fatigue, and coping. The influence of high social support to improve the relationship between stress and HRQOL underscores the importance of a comprehensive plan to address psychosocial factors.

  7. Ethnicity moderates the relationship between perceived stress and benefit finding in HIV+ men who have sex with men (MSM).

    Science.gov (United States)

    Seay, Julia S; Fekete, Erin M; Antoni, Michael H; Ironson, Gail; Fletcher, MaryAnn; Schneiderman, Neil

    2014-04-01

    Numerous studies conducted within the USA demonstrate higher levels of benefit finding in ethnic minority individuals compared to nonminority individuals living with chronic disease. As benefit finding may be a salient buffer for the effects of stress, the current study examined the association between perceived stress and benefit finding in human immunodeficiency virus (HIV)+ men who have sex with men (MSM) living in the southeast USA and investigated whether ethnicity was a moderator of this relationship. We hypothesized that benefit finding would be greater in ethnic minority MSM than in white MSM and that ethnic minority MSM with high levels of stress would experience greater benefit finding than their white MSM counterparts. The current study utilized baseline (T1) and 3-month follow-up (T2) data drawn from a previous trial of a psychosocial intervention in HIV+ MSM. Participants were 130 HIV+ MSM; 52 % were white and 48 % belonged to minority ethnic groups (African-American, Caribbean-American, Hispanic). Analyses revealed that benefit finding was greater in ethnic minority MSM at baseline; however, this difference became nonsignificant when age, education level, highly active antiretroviral therapy adherence, and CD4 count were added to the model. Moderated regression analyses revealed a significant interaction between T1 perceived stress and ethnicity in predicting T2 benefit finding, such that higher levels of T1 perceived stress predicted lower levels of T2 benefit finding in ethnic minority MSM only. This association was independent of intervention group assignment. The current study's results highlight potential differences in the relationship between stress and benefit finding processes in white and ethnic minority HIV+ MSM.

  8. Integrated Inflammatory Stress (ITIS) Model

    DEFF Research Database (Denmark)

    Bangsgaard, Elisabeth O.; Hjorth, Poul G.; Olufsen, Mette S.

    2017-01-01

    maintains a long-term level of the stress hormone cortisol which is also anti-inflammatory. A new integrated model of the interaction between these two subsystems of the inflammatory system is proposed and coined the integrated inflammatory stress (ITIS) model. The coupling mechanisms describing....... A constant activation results in elevated levels of the variables in the model while a prolonged change of the oscillations in ACTH and cortisol concentrations is the most pronounced result of different LPS doses predicted by the model....

  9. The moderating role of rational beliefs in the relationship between irrational beliefs and posttraumatic stress symptomology.

    Science.gov (United States)

    Hyland, Philip; Shevlin, Mark; Adamson, Gary; Boduszek, Daniel

    2014-05-01

    Rational Emotive Behaviour Therapy (REBT) assumes that rational beliefs act as cognitive protective factors against the development of psychopathology; however little empirical evidence exists regarding the nature of the possible protective effects that they offer. The current study investigates whether rational beliefs moderate the impact of irrational beliefs on posttraumatic stress symptomology (PTS). Three hundred and thirteen active law enforcement, military, and related emergency service personnel took part in the current study. Sequential moderated multiple regression analysis was employed to investigate: (i) the direct impact of irrational beliefs on PTS; (ii) the direct impact of rational beliefs on PTS; (iii) the moderating effects of rational beliefs in the relationship between irrational beliefs and PTS. The irrational beliefs predicted by REBT theory emerged as critical predictors of PTS symptomology, in particular Depreciation beliefs. Rational beliefs (Preferences, and Acceptance beliefs) had a direct, negative impact on levels of PTS, and Acceptance beliefs moderated the impact of Catastrophizing beliefs on PTS. Irrational beliefs are important cognitive vulnerability factors in symptoms of PTS, while rational beliefs (Acceptance) appear to have a protective role in the emergence of PTS symptoms, both directly and by moderating the impact of Catastrophizing beliefs.

  10. The Moderating Role of Coping Skills on the Relationship between Self-Leadership and Stress among College Students

    Science.gov (United States)

    Maykrantz, Sherry Azadi

    2017-01-01

    Stress remains the number one health concern among college students today; therefore, research on student stress is imperative, from both an organizational and an individual perspective. This research study explored the moderating role of coping skills on the relationship between self-leadership and stress among college students. Using the ALSQ,…

  11. Links between white matter microstructure and cortisol reactivity to stress in early childhood: evidence for moderation by parenting.

    Science.gov (United States)

    Sheikh, Haroon I; Joanisse, Marc F; Mackrell, Sarah M; Kryski, Katie R; Smith, Heather J; Singh, Shiva M; Hayden, Elizabeth P

    2014-01-01

    Activity of the hypothalamic-pituitary-adrenal axis (measured via cortisol reactivity) may be a biological marker of risk for depression and anxiety, possibly even early in development. However, the structural neural correlates of early cortisol reactivity are not well known, although these would potentially inform broader models of mechanisms of risk, especially if the early environment further shapes these relationships. Therefore, we examined links between white matter architecture and young girls' cortisol reactivity and whether early caregiving moderated these links. We recruited 45 6-year-old girls based on whether they had previously shown high or low cortisol reactivity to a stress task at age 3. White matter integrity was assessed by calculating fractional anisotropy (FA) of diffusion-weighted magnetic resonance imaging scans. Parenting styles were measured via a standardized parent-child interaction task. Significant associations were found between FA in white matter regions adjacent to the left thalamus, the right anterior cingulate cortex, and the right superior frontal gyrus (all ps parent positive affect showing white matter structure more similar to that of low stress reactive girls. Results show associations between white matter integrity of various limbic regions of the brain and early cortisol reactivity to stress and provide preliminary support for the notion that parenting may moderate associations.

  12. Thermomechanical Stress in Cryopreservation Via Vitrification With Nanoparticle Heating as a Stress-Moderating Effect.

    Science.gov (United States)

    Eisenberg, David P; Bischof, John C; Rabin, Yoed

    2016-01-01

    This study focuses on thermomechanical effects in cryopreservation associated with a novel approach of volumetric heating by means on nanoparticles in an alternating electromagnetic field. This approach is studied for the application of cryopreservation by vitrification, where the crystalline phase is completely avoided-the cornerstone of cryoinjury. Vitrification can be achieved by quickly cooling the material to cryogenic storage, where ice cannot form. Vitrification can be maintained at the end of the cryogenic protocol by quickly rewarming the material back to room temperature. The magnitude of the rewarming rates necessary to maintain vitrification is much higher than the magnitude of the cooling rates that are required to achieve it in the first place. The most common approach to achieve the required cooling and rewarming rates is by exposing the specimen's surface to a temperature-controlled environment. Due to the underlying principles of heat transfer, there is a size limit in the case of surface heating beyond which crystallization cannot be prevented at the center of the specimen. Furthermore, due to the underlying principles of solid mechanics, there is a size limit beyond which thermal expansion in the specimen can lead to structural damage and fractures. Volumetric heating during the rewarming phase of the cryogenic protocol can alleviate these size limitations. This study suggests that volumetric heating can reduce thermomechanical stress, when combined with an appropriate design of the thermal protocol. Without such design, this study suggests that the level of stress may still lead to structural damage even when volumetric heating is applied. This study proposes strategies to harness nanoparticles heating in order to reduce thermomechanical stress in cryopreservation by vitrification.

  13. The influence of mastery on mother's health in middle years: Moderating role of stressful life context.

    Science.gov (United States)

    King, Victoria; Wickrama, K A S; Klopack, Erick; Lorenz, Frederick O

    2018-06-07

    Using data from 416 middle-aged mothers gathered over the course of a decade, this study examined the influence of mastery trajectories (the initial level and change), on change in physical health. Mastery is defined as one's ability to control and influence his/her life and environment to reach a desired outcome or goal. Both the initial level and change in mastery from 1991 to 1994 were associated with decreased physical health problems over the middle years (1991-2001). Contextual moderation of this association by stressful life contexts including negative life events and work-family conflict was investigated. Moderation analysis showed that under conditions of low contextual life stressors, the level and increase in mastery significantly contributed to decreases in physical health problems in middle-aged mothers. Alternatively, conditions of high contextual life stressors inhibited the ability of mastery to influence physical health of mothers, suggesting that the positive health impact of mastery on physical health is mitigated by stressful life experiences. Implications for the need to maintain important personal resources, such as mastery, during times of stress are discussed. Copyright © 2018 John Wiley & Sons, Ltd.

  14. Heat stress and sudden infant death syndrome--stress gene expression after exposure to moderate heat stress

    DEFF Research Database (Denmark)

    Rohde, Marianne Cathrine; Corydon, Thomas Juhl; Hansen, Jakob

    2013-01-01

    The aim of the present study was to investigate stress gene expression in cultured primary fibroblasts established from Achilles tendons collected during autopsies from sudden infant death syndrome (SIDS) cases, and age-matched controls (infants dying in a traumatic event). Expression of 4 stress...... responsive genes, HSPA1B, HSPD1, HMOX1, and SOD2, was studied by quantitative reverse transcriptase PCR analysis of RNA purified from cells cultured under standard or various thermal stress conditions. The expression of all 4 genes was highly influenced by thermal stress in both SIDS and control cells. High...... interpersonal variance found in the SIDS group indicated that they represented a more heterogeneous group than controls. The SIDS group responded to thermal stress with a higher expression of the HSPA1B and HSPD1 genes compared to the control group, whereas no significant difference was observed...

  15. Use of e-Learning for Stress management – Multi-group moderation analysis

    Directory of Open Access Journals (Sweden)

    Aamir Sarwar

    2016-12-01

    Full Text Available The goal of this study is to find out the moderating role of type of industry and different levels of management with respect to eLearning perception, eLearning advantages and use of eLearning for Stress Management. Study tried to find out relationship between perceptions of eLearning, eLearning Advantages, perception of using eLearning for corporate training and more specifically for stress management. A cross sectional survey is conducted through structured questionnaire to collect the data from 686 managers working at different levels including 331 from manufacturing sector and 355 from services sector. Results of the study show positive relationship between perception of eLearning and eLearning for stress management and this relationship is significantly stronger for services industry. Positive relationship between eLearning advantages and eLearning for stress management and this relationship is significantly stronger for manufacturing industry. Study also revealed that positive relationship between eLearning perception and eLearning for stress management and this relationship is not significantly stronger for senior management than for middle management.

  16. Job stress and family social behavior: the moderating role of neuroticism.

    Science.gov (United States)

    Wang, Shu-wen; Repetti, Rena L; Campos, Belinda

    2011-10-01

    We investigated the role of neuroticism in the associations between job stress and working adults' social behavior during the first hour after work with their spouse and school-age children. Thirty dual-earner families were videotaped in their homes on two weekday afternoons and evenings. An observational coding system was developed to assess behavioral involvement and negative emotion expression. Participants also completed self-report measures of job stressors and trait neuroticism. There were few overall associations between job stress and social behavior during the first hour adults were at home with their spouse and school-age children. However, significant moderator effects indicated that linkages between work experiences and family behavior varied for men who reported different levels of trait neuroticism, which captures a dispositional tendency toward emotional instability. Among men who reported high neuroticism, job stress was linked to more active and more negative social behavior. Conversely, for men reporting low neuroticism, job stress was related to less talking and less negative emotion. These patterns were not found for the women in the study. The findings suggest that when work is stressful, men who are higher on neuroticism (i.e., less emotionally stable) may show a negative spillover effect, whereas men who are lower on neuroticism (i.e., more emotionally stable) may withdraw from social interactions. (PsycINFO Database Record (c) 2011 APA, all rights reserved).

  17. The serotonin transporter gene polymorphism 5-HTTLPR moderates the effects of stress on attention-deficit/hyperactivity disorder.

    Science.gov (United States)

    van der Meer, Dennis; Hartman, Catharina A; Richards, Jennifer; Bralten, Janita B; Franke, Barbara; Oosterlaan, Jaap; Heslenfeld, Dirk J; Faraone, Stephen V; Buitelaar, Jan K; Hoekstra, Pieter J

    2014-12-01

    The role of the serotonin transporter gene polymorphism 5-HTTLPR in attention-deficit/hyperactivity disorder (ADHD) is unclear. Heterogeneity of findings may be explained by gene-environment interactions (GxE), as it has been suggested that S-allele carriers are more reactive to psychosocial stress than L-allele homozygotes. This study aimed to investigate whether 5-HTTLPR genotype moderates the effects of stress on ADHD in a multisite prospective ADHD cohort study. 5-HTTLPR genotype, as well as the number of stressful life events in the past 5 years and ongoing long-term difficulties, was determined in 671 adolescents and young adults with ADHD, their siblings, and healthy controls (57.4% male, average age 17.3 years). Linear mixed models, accounting for family relatedness, were applied to investigate the effects of genotype, experienced stress, and their interaction on ADHD severity at time point T2, while controlling for ADHD severity at T1 (mean follow-up time 5.9 years) and for comorbid internalizing problems at T2. The interaction between genotype and stress significantly predicted ADHD severity at T2 (p = .006), which was driven by the effect on hyperactivity-impulsivity (p = .004). Probing of the interaction effect made clear that S-allele carriers had a significantly more positive correlation between stress and ADHD severity than L-allele homozygotes. The results show that the interaction between 5-HTTLPR and stress is a mechanism involved particularly in the hyperactivity/impulsivity dimension of ADHD, and that this is independent of comorbid internalizing problems. Further research into the neurobiological mechanisms underlying this interaction effect is warranted. © 2014 The Authors. Journal of Child Psychology and Psychiatry. © 2014 Association for Child and Adolescent Mental Health.

  18. Effects of moderate treadmill exercise and fluoxetine on behavioural and cognitive deficits, hypothalamic-pituitary-adrenal axis dysfunction and alternations in hippocampal BDNF and mRNA expression of apoptosis - related proteins in a rat model of post-traumatic stress disorder.

    Science.gov (United States)

    Shafia, Sakineh; Vafaei, Abbas Ali; Samaei, Seyed Afshin; Bandegi, Ahmad Reza; Rafiei, Alireza; Valadan, Reza; Hosseini-Khah, Zahra; Mohammadkhani, Raziyeh; Rashidy-Pour, Ali

    2017-03-01

    Post-traumatic stress disorder (PTSD) is a condition that develops after an individual has experienced a major trauma. Currently, selective serotonin reuptake inhibitors (SSRIs) like fluoxetine are the first-line choice in PTSD drug treatment but their moderate response rates and side effects indicate an urgent need for the development of new treatment. Physical activity is known to improve symptoms of certain neuropsychiatric disorders. The present study investigated the effects of moderate treadmill exercise, the antidepressant fluoxetine and the combined treatment on behavioural deficits, and hypothalamic-pituitary-adrenal (HPA) axis dysfunction. We also examined alternations in hippocampal brain-derived neurotrophic factor (BDNF) and mRNA expression of apoptosis - related proteins in a rat model of PTSD: the single prolonged stress (SPS) model. Rats were exposed to SPS (restraint for 2h, forced swimming for 20min and ether anaesthesia) and were then kept undisturbed for 14days. After that, SPS rats were subjected to chronic treatment with fluoxetine (10mg/kg/day, for 4weeks), moderate treadmill running (4weeks, 5day per week) and the combined treatment (fluoxetine plus treadmill exercise), followed by behavioural, biochemical and apoptosis markers assessments. SPS rats exhibited increased anxiety levels in the elevated plus maze and light/dark box, impaired fear conditioning and extinction in inhibitory avoidance (IA) task, impaired spatial memory in a recognition location memory task and enhanced negative feedback on the HPA axis following a dexamethasone suppression test. SPS rats also showed reduced hippocampal BDNF and enhanced apoptosis. Moderate treadmill exercise, fluoxetine and the combined treatment alleviated the SPS-induced alterations in terms of anxiety levels, HPA axis inhibition, IA conditioning and extinction, hippocampal BDNF and apoptosis markers. Furthermore, the combined treatment was more effective than fluoxetine alone, but in most tests

  19. Pre-treatment Social Anxiety Severity Moderates the Impact of Mindfulness-Based Stress Reduction and Aerobic Exercise

    Science.gov (United States)

    Jazaieri, Hooria; Lee, Ihno A.; Goldin, Philippe R.; Gross, James J.

    2015-01-01

    We examined whether social anxiety severity at pre-treatment would moderate the impact of Mindfulness-Based Stress Reduction (MBSR) or Aerobic Exercise (AE) for generalized social anxiety disorder. MBSR and AE produced equivalent reductions in weekly social anxiety symptoms. Improvements were moderated by pre-treatment social anxiety severity. PMID:25684277

  20. Psychological stress moderates the relationship between running volume and CD4+ T cell subpopulations.

    Science.gov (United States)

    Rehm, K E; Sunesara, I; Tull, M T; Marshall, G D

    2016-01-01

    Endurance-based exercise training can lead to alterations in components of the immune system, but it is unknown how psychological stress (another potent immunomodulator) may impact these changes. The purpose of this study was to determine the moderating role of psychological stress on exercise-induced immune changes. Twenty-nine recreational runners were recruited for this study four weeks before completing a marathon. Each subject reported: weekly training volume (miles/wk) for the week prior to the study visit; completed the Perceived Stress Scale (PSS), the state version of the State-Trait Anxiety Inventory (STAI) and the Penn State Worry Questionnaire (PSWQ); and donated blood for assessment of CD4+ T cell subpopulations and mitogen-induced cytokine production. Participants ran an average of 30 (±13.4) miles (1 mile=1.6 km) per week. Average values (SD) for immune biomarkers were: regulatory T cells (Treg), 3.2% (±1.2%); type 1 regulatory cells (Tr1), 27.1% (±8.3%); T helper 3 (Th3), 1.8% (±0.7%); interferon gamma (IFNγ), 3.1 pg/ml (±1.0); interleukin (IL)-4, 1.4 pg/ml (±1.1); IFNγ/IL-4, 8.6 (±1.2); IL-10, 512 pg/ml (±288). There was a significant relationship between running volume and both Treg cell numbers (slope of the regression line (β)=0.05, p less than 0.001) and IL-10 production β=-10.6, p=0.002), and there was a trending relationship between running volume and Tr1 cell numbers (β=-0.2%, p=0.064). Perceived stress was a trending moderator of the running volume-Treg relationship, whereas worry was a significant moderator of the running volume-IFNγ and running volume-IFNγ/IL-4 relationships. These data indicate that various forms of psychological stress can impact endurance exercise-based changes in certain immune biomarkers. These changes may reflect an increased susceptibility to clinical risks in some individuals.

  1. Ownership type and team climate in elderly care facilities: the moderating effect of stress factors.

    Science.gov (United States)

    Heponiemi, Tarja; Elovainio, Marko; Kouvonen, Anne; Noro, Anja; Finne-Soveri, Harriet; Sinervo, Timo

    2012-03-01

    This paper is a report of a study examining the association between ownership type and perceived team climate among older people care staff. In addition, we examined whether work stress factors (time pressure, resident-related stress, role conflicts and role ambiguity) mediated or moderated the above mentioned association. There has been a trend towards contracting out in older people care facilities in Finland and the number of private for-profit firms has increased. Studies suggest that there may be differences in employee well-being and quality of care according to the ownership type of older people care. Cross-sectional survey data was collected during the autumn of 2007 from 1084 Finnish female older people care staff aged 18-69 years were used. Team Climate Inventory was used to measure team climate. Ownership type was divided into four categories: for-profit sheltered homes, not-for-profit sheltered homes, public sheltered homes and not-for-profit nursing homes. Analyses of covariance were used to examine the associations. Team climate dimensions participative safety, vision and support for innovation were higher in not-for-profit organizations (both sheltered homes and nursing homes) compared to for-profit sheltered homes and public sheltered homes. Stress factors did not account for these associations but acted as moderators in a way that in terms of task orientation and participative safety employees working in for-profit organizations seemed to be slightly more sensitive to work-related stress than others. Our results suggest that for-profit organizations and public organizations may have difficulties in maintaining their team climate. In consequence, these organizations should focus more effort on improving their team climate. © 2011 Blackwell Publishing Ltd.

  2. Chronic family stress moderates the association between a TOMM40 variant and triglyceride levels in two independent Caucasian samples

    DEFF Research Database (Denmark)

    Jiang, Rong; Brummett, Beverly H; Hauser, Elizabeth R

    2013-01-01

    independent Caucasian samples (242 U.S. women and men; 466 Danish men) testing the hypothesis that chronic family stress also moderates the association between rs157580 and triglyceride levels. The interaction of rs157580 and family stress in predicting triglyceride levels was statistically significant...... in the U.S. sample (p=0.004) and marginally significant (p=0.075) in the Danish sample. The G allele of rs157580 was associated with increased triglyceride levels among family stressed cases in both samples compared with A/A cases, but not among controls. Chronic family stress moderates the association......TOMM40 SNP rs157580 has been associated with triglyceride levels in genome-wide association studies (GWAS). Chronic caregiving stress moderates the association between triglyceride levels and a nearby SNP rs439401 that is associated with triglyceride levels in GWAS. Here, we report data from two...

  3. Preschoolers' genetic, physiological, and behavioral sensitivity factors moderate links between parenting stress and child internalizing, externalizing, and sleep problems.

    Science.gov (United States)

    Davis, Molly; Thomassin, Kristel; Bilms, Joanie; Suveg, Cynthia; Shaffer, Anne; Beach, Steven R H

    2017-05-01

    This study examined three potential moderators of the relations between maternal parenting stress and preschoolers' adjustment problems: a genetic polymorphism-the short allele of the serotonin transporter (5-HTTLPR, ss/sl allele) gene, a physiological indicator-children's baseline respiratory sinus arrhythmia (RSA), and a behavioral indicator-mothers' reports of children's negative emotionality. A total of 108 mothers (M age  = 30.68 years, SD age  = 6.06) reported on their parenting stress as well as their preschoolers' (M age  = 3.50 years, SD age  = 0.51, 61% boys) negative emotionality and internalizing, externalizing, and sleep problems. Results indicated that the genetic sensitivity variable functioned according to a differential susceptibility model; however, the results involving physiological and behavioral sensitivity factors were most consistent with a diathesis-stress framework. Implications for prevention and intervention efforts to counter the effects of parenting stress are discussed. © 2017 Wiley Periodicals, Inc.

  4. Adversity and persecutory ideation: A moderated mediational model.

    Science.gov (United States)

    Valiente, Carmen; Espinosa, Regina; Villavicencio, Patricia; Cantero, Dolores; Fuentenebro, Filiberto

    2017-12-01

    Adversity has been identified as an important factor in models of psychopathology and can help in understanding persecutory ideation, although potential moderators and mediators for adult psychopathology have not been sufficiently examined. Experiential avoidance (EA) and Self-esteem (SE) are relevant factors to understand how adversity leads to persecutory ideation. This study hypothesized that adversity would be associated with persecutory ideation through heightened EA, and that this association would be strengthened in individuals with a discrepant high SE. Participants with persecutory ideation (n = 52), with depression (n = 35) and healthy controls (n = 51) were assessed with the Trauma History Screen, the Paranoia and Deservedness Scale, and the Beck Depression Inventory. A SE discrepancy index was calculated subtracting the normalized explicit SE score from the normalized implicit SE score (measured by a version of a Go/No-go association task). Our analysis revealed that adversity was associated with higher levels of paranoia and was mediated by EA. In addition, we found that the relationship between adversity and EA was moderated by SE discrepancy. Identification of moderating and mediating variables allows for increased understanding of persecutory ideation and the processes that should be targeted in the course of recovery. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Mathematical modeling of the moderate storm on 28 February 2008

    Science.gov (United States)

    Eroglu, Emre

    2018-04-01

    The sun is an active star with plasma-filled prominences. The sudden ejection of the solar plasma creates storms in the form of bursting or spraying. A magnetospheric storm is a typical phenomenon that lasts 1-3 days and involves all magnetosphere from the earth's ionosphere to the magnetotail. The storms are known by different categorical names such as weak, moderate, strong, intense. One of these is the moderate geomagnetic storm on February 28, 2008, which occurred in the 24th solar cycle. The reason for discussing this storm is that it is the first moderate storm in the 24th solar cycle. In this study, we investigate the storm and entered the 24th solar cycle. The correlation among the parametres has been investigated via statistics. The solar wind parameters and the zonal geomagnetic indices have been analyzed separately and then the interaction with each other has been exhibited. The author has concluded the work with two new nonlinear mathematical models. These explain the storm with 79.1% and 87.5% accuracy.

  6. The Evolution of Post-Traumatic Stress Disorder following Moderate-to-Severe Traumatic Brain Injury.

    Science.gov (United States)

    Alway, Yvette; Gould, Kate Rachel; McKay, Adam; Johnston, Lisa; Ponsford, Jennie

    2016-05-01

    Increasing evidence indicates that post-traumatic stress disorder (PTSD) may develop following traumatic brain injury (TBI), despite most patients having no conscious memory of their accident. This prospective study examined the frequency, timing of onset, symptom profile, and trajectory of PTSD and its psychiatric comorbidities during the first 4 years following moderate-to-severe TBI. Participants were 85 individuals (78.8% male) with moderate or severe TBI recruited following admission to acute rehabilitation between 2005 and 2010. Using the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Disorders (SCID-I), participants were evaluated for pre- and post-injury PTSD soon after injury and reassessed at 6 months, 12 months, 2 years, 3 years, and 4 years post-injury. Over the first 4 years post-injury, 17.6% developed injury-related PTSD, none of whom had PTSD prior to injury. PTSD onset peaked between 6 and 12 months post-injury. The majority of PTSD cases (66.7%) had a delayed-onset, which for a third was preceded by subsyndromal symptoms in the first 6 months post-injury. PTSD frequency increased over the first year post-injury, remained stable during the second year, and gradually declined thereafter. The majority of subjects with PTSD experienced a chronic symptom course and all developed one or more than one comorbid psychiatric disorder, with mood, other anxiety, and substance-use disorders being the most common. Despite event-related amnesia, post-traumatic stress symptoms, including vivid re-experiencing phenomena, may develop following moderate-to-severe TBI. Onset is typically delayed and symptoms may persist for several years post-injury.

  7. Posttraumatic stress disorder as a moderator of the association between negative affect and bulimic symptoms: an ecological momentary assessment study.

    Science.gov (United States)

    Karr, Trisha M; Crosby, Ross D; Cao, Li; Engel, Scott G; Mitchell, James E; Simonich, Heather; Wonderlich, Stephen A

    2013-01-01

    The purpose of this study was to examine the potential moderating effect of posttraumatic stress disorder (PTSD) on the emotion-behavior relationship in individuals with bulimia nervosa (BN). A total of 119 women with BN were involved in the study. Participants were divided into 2 groups: those with BN and PTSD (n = 20) and those with BN only (n = 99). Ecological momentary assessment procedures were used for the examination of affect, frequency of bulimic behaviors, and the relationship of affect and bulimic behavior over time. The Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Axis I Disorders was conducted for the diagnosis of BN, PTSD, mood disorders, anxiety disorders, and substance use disorders. Mood disorders, anxiety disorders, and substance use disorders functioned as covariates in all analyses. Statistical models showed that those in the PTSD group reported a greater daily mean level of negative affect (NA) and a greater daily frequency of bulimic behaviors than those in the BN-only group. Moderation was found for the association between NA and time in that the PTSD group showed a faster acceleration in NA before purging and faster deceleration in NA after purging. The association between positive affect and time was also moderated by group, indicating that the PTSD group had a faster acceleration in positive affect after purging than the BN-only group. These findings highlight the importance of recognizing PTSD when interpreting the emotion-behavior relationship in individuals with BN. Published by Elsevier Inc.

  8. Mother's Childrearing History and Current Parenting: Patterns of Association and the Moderating Role of Current Life Stress

    Science.gov (United States)

    Hill, Carri; Stein, Jennifer; Keenan, Kate; Wakschlag, Lauren S.

    2006-01-01

    This study examined the association between positive and negative aspects of childrearing history and current parenting and the moderating effect of current stress. Seventy mother-child dyads participated in this study. Mothers provided retrospective reports of childrearing histories and current reports of life stress. Parenting was assessed via…

  9. Gender as a Moderator of the Relation between Race-Related Stress and Mental Health Symptoms for African Americans

    Science.gov (United States)

    Greer, Tawanda M.; Laseter, Adrian; Asiamah, David

    2009-01-01

    The present study tested gender as a moderator of the relationship between race-related stress and mental health symptoms among African American adults. Because African American women are exposed to stressors associated with race and gender, we hypothesized that African American women would have higher levels of race-related stress and more severe…

  10. The moderating effects of aging and cognitive abilities on the association between work stress and negative affect.

    Science.gov (United States)

    Hyun, Jinshil; Sliwinski, Martin J; Almeida, David M; Smyth, Joshua M; Scott, Stacey B

    2018-05-01

    Given that the association between work stress and negative affect can exacerbate negative health and workplace outcomes, it is important to identify the protective and risk factors that moderate this association. Socioemotional aging and cognitive abilities might influence how people utilize emotion regulation skills and engage in practical problem solving to manage their work stress. The aim of this study is to examine whether age and cognitive abilities independently and interactively moderate the association between work-related stress and negative affect. A diverse working adult sample (N = 139, age 25-65, 69% of females) completed a cross-sectional survey that assessed chronic work stress, negative affect, and fluid and crystallized cognitive abilities. Results from regression analyses suggested that both fluid and crystallized cognitive abilities, but not age, moderated the association between work stress and negative affect. Further, we found that crystallized cognition had a stronger attenuating effect on the work stress-negative affect association for older compared to younger workers. The moderating effect of fluid cognition was invariant across age. Our findings demonstrate that cognitive abilities are an important personal resource that might protect individuals against the negative impacts of work stress and negative affect. Although the role that fluid cognition plays in work stress-negative affect association is comparably important for both younger and older workers, crystallized cognition might play a more valuable role for older than younger workers.

  11. Moderate summer heat stress does not modify immunological parameters of Holstein dairy cows

    Science.gov (United States)

    Lacetera, Nicola; Bernabucci, Umberto; Ronchi, Bruno; Scalia, Daniela; Nardone, Alessandro

    2002-02-01

    The study was undertaken during spring and summer months in a territory representative of the Mediterranean climate to assess the effects of season on some immunological parameters of dairy cows. Twenty Holstein cows were used. Eleven of those cows gave birth during spring; the remaining nine cows gave birth in summer. The two groups of cows were homogeneous for parity. Values of air temperatures and relative humidity were recorded both during spring and summer, and were utilized to calculate the temperature humidity index (THI). One week before the expected calving, rectal temperatures and respiratory rates of the cows were recorded (1500 hours), and cell-mediated immunity was assessed by measuring the proliferation of mitogen-stimulated peripheral blood mononuclear cells (PBMC). Within 3 h of calving, one colostrum sample was taken from each cow and analysed to determine content of immunoglobulin (Ig) G1, IgG2, IgM and IgA. At 48 h after birth, passive immunization of the calves was assessed by measuring total serum IgG. During summer, daytime (0900-2000 hours) THI values were above the upper critical value of 72 [75.2, (SD 2.6)] indicating conditions that could represent moderate heat stress. That THI values were able to predict heat stress was confirmed by the values of rectal temperatures and respiratory rates, which were higher ( P cows. Results indicated that moderate heat stress due to the hot Mediterranean summer does not modify cell-mediated immunity, the protective value of colostrum and passive immunization of the offspring in dairy cows.

  12. Coping strategies as mediators and moderators between stress and quality of life among parents of children with autistic disorder.

    Science.gov (United States)

    Dardas, Latefa A; Ahmad, Muayyad M

    2015-02-01

    The purpose of this cross-sectional study was to examine coping strategies as mediators and moderators between stress and quality of life (QoL) among parents of children with autistic disorder. The convenience sample of the study consisted of 184 parents of children with autistic disorder. Advanced statistical methods for analyses of mediator and moderator effects of coping strategies were used. The results revealed that 'accepting responsibility' was the only mediator strategy in the relationship between stress and QoL. The results also revealed that only 'seeking social support' and 'escape avoidance' were moderator strategies in the relationship between stress and QoL. This study is perhaps the first to investigate the mediating and moderating effects of coping on QoL of parents of children with autistic disorder. Recommendations for practice and future research are presented. © 2013 John Wiley & Sons, Ltd.

  13. Masculinity and Bystander Attitudes: Moderating Effects of Masculine Gender Role Stress.

    Science.gov (United States)

    Leone, Ruschelle M; Parrott, Dominic J; Swartout, Kevin M; Tharp, Andra Teten

    2016-01-01

    The purpose of the current study was to examine the bystander decision-making process as a mechanism by which men's adherence to various dimensions of traditional masculinity is associated with their confidence to intervene in sexually aggressive events. Further, this study examined the stress men experience from their attempts to adhere to traditional male gender roles as a moderator of this mediational path. Participants ( n = 252) completed measures of traditional masculinity, decisional balance (i.e., weighing the pros and cons) for intervening, masculine gender roles stress, and bystander efficacy. The belief that men must attain social status was associated with more confidence in men's ability to intervene. This effect was mediated by greater perceived positive consequences for intervention among men high, but not low, in masculine gender role stress. The belief that men should be tough and aggressive was associated with greater perceived negative consequences for intervention and less confidence to intervene. The belief that men should not act in stereotypically feminine ways was directly associated with less confidence for intervention. Findings highlight the importance of examining masculinity from a multidimensional perspective to better understand how adherence to various norms differentially influences bystander behavior. These findings may help to inform bystander intervention programming.

  14. Masculinity and Bystander Attitudes: Moderating Effects of Masculine Gender Role Stress

    Science.gov (United States)

    Leone, Ruschelle M.; Parrott, Dominic J.; Swartout, Kevin M.; Tharp, Andra Teten

    2018-01-01

    Objective The purpose of the current study was to examine the bystander decision-making process as a mechanism by which men’s adherence to various dimensions of traditional masculinity is associated with their confidence to intervene in sexually aggressive events. Further, this study examined the stress men experience from their attempts to adhere to traditional male gender roles as a moderator of this mediational path. Method Participants (n = 252) completed measures of traditional masculinity, decisional balance (i.e., weighing the pros and cons) for intervening, masculine gender roles stress, and bystander efficacy. Results The belief that men must attain social status was associated with more confidence in men’s ability to intervene. This effect was mediated by greater perceived positive consequences for intervention among men high, but not low, in masculine gender role stress. The belief that men should be tough and aggressive was associated with greater perceived negative consequences for intervention and less confidence to intervene. The belief that men should not act in stereotypically feminine ways was directly associated with less confidence for intervention. Conclusions Findings highlight the importance of examining masculinity from a multidimensional perspective to better understand how adherence to various norms differentially influences bystander behavior. These findings may help to inform bystander intervention programming. PMID:29593932

  15. Does perceived stress moderate the association between depressive symptoms and socioemotional and behavioural strengths and difficulties in adolescence?

    Science.gov (United States)

    Lätsch, Alexander

    2018-04-01

    More and more students report high level of perceived stress during childhood and adolescence, which is associated with socioemotional and behavioural strengths and difficulties. This study aims-based on the cognitive vulnerability-transactional stress theory-to examine perceived stress in early adolescence as a potential moderator in the association between depressive symptoms and socioemotional and behavioural strengths and difficulties from early to middle adolescence. Results of latent moderated structural equations with questionnaire data from a longitudinal study with 1,088 German students (Time 1: M age  = 13.70, SD = 0.53; Time 2: N = 845, M age  = 15.32, SD = 0.49) indicate that perceived stress functions as a moderator in the above-mentioned association and dominates the interaction if perceived strongly. Copyright © 2017 John Wiley & Sons, Ltd.

  16. Stress and sleep reactivity: a prospective investigation of the stress-diathesis model of insomnia.

    Science.gov (United States)

    Drake, Christopher L; Pillai, Vivek; Roth, Thomas

    2014-08-01

    To prospectively assess sleep reactivity as a diathesis of insomnia, and to delineate the interaction between this diathesis and naturalistic stress in the development of insomnia among normal sleepers. Longitudinal. Community-based. 2,316 adults from the Evolution of Pathways to Insomnia Cohort (EPIC) with no history of insomnia or depression (46.8 ± 13.2 y; 60% female). None. Participants reported the number of stressful events they encountered at baseline (Time 1), as well as the level of cognitive intrusion they experienced in response to each stressor. Stressful events (OR = 1.13; P stress-induced cognitive intrusion (OR = 1.61; P stressful events on risk for insomnia (P sleep reactivity significantly increased risk for insomnia (OR = 1.78; P sleep reactivity moderated the effects of stress-induced intrusion (P sleep reactivity. Trait sleep reactivity also constituted a significant risk for depression (OR = 1.67; P sleep reactivity is a significant risk factor for incident insomnia, and that it triggers insomnia by exacerbating the effects of stress-induced intrusion. Sleep reactivity is also a precipitant of depression, as mediated by insomnia. These findings support the stress-diathesis model of insomnia, while highlighting sleep reactivity as an important diathesis. Drake CL, Pillai V, Roth T. Stress and sleep reactivity: a prospective investigation of the stress-diathesis model of insomnia.

  17. Oxidative stress, telomere shortening, and DNA methylation in relation to low-to-moderate occupational exposure to welding fumes.

    Science.gov (United States)

    Li, Huiqi; Hedmer, Maria; Wojdacz, Tomasz; Hossain, Mohammad Bakhtiar; Lindh, Christian H; Tinnerberg, Håkan; Albin, Maria; Broberg, Karin

    2015-10-01

    Evidence suggests that exposure to welding fumes is a risk factor for lung cancer. We examined relationships between low-to-moderate occupational exposure to particles from welding fumes and cancer-related biomarkers for oxidative stress, changes in telomere length, and alterations in DNA methylation. We enrolled 101 welders and 127 controls (all currently nonsmoking men) from southern Sweden. We performed personal sampling of respirable dust and measured 8-oxodG concentrations in urine using a simplified liquid chromatography tandem mass spectrometry method. Telomere length in peripheral blood was measured by quantitative polymerase chain reaction. Methylation status of 10 tumor suppressor genes was determined by methylation-sensitive high-resolution melting analysis. All analyses were adjusted for age, body mass index, previous smoking, passive smoking, current residence, and wood burning stove/boiler at home. Welders were exposed to respirable dust at 1.2 mg/m(3) (standard deviation, 3.3 mg/m(3); range, 0.1-19.3), whereas control exposures did not exceed 0.1 mg/m(3) (P < 0.001). Welders and controls did not differ in 8-oxodG levels (β = 1.2, P = 0.17) or relative telomere length (β = -0.053, P = 0.083) in adjusted models. Welders showed higher probability of adenomatous polyposis coli (APC) methylation in the unadjusted model (odds ratio = 14, P = 0.014), but this was not significant in the fully adjusted model (P = 0.052). Every working year as a welder was associated with 0.0066 units shorter telomeres (95% confidence interval -0.013 to -0.00053, P = 0.033). Although there were no clear associations between concentrations of respirable dust and the biomarkers, there were modest signs of associations between oxidative stress, telomere alterations, DNA methylation, and occupational exposure to low-to-moderate levels of particles. © 2015 Wiley Periodicals, Inc.

  18. An examination of psychosocial variables moderating the relationship between life stress and injury time-loss among athletes of a high standard.

    Science.gov (United States)

    Ford, I W; Eklund, R C; Gordon, S

    2000-05-01

    Based on Williams and Andersen's model of stress and athletic injury, six psychosocial variables were assessed as possible moderators of the relationship between life stress and injury among 121 athletes (65 males, 56 females) competing in a variety of sports at state, national or international level. No significant effects of the sex of the participants were evident. Correlational analyses revealed moderator effects of several variables. Specifically, dispositional optimism and hardiness were related to decreased injury time-loss in athletes when positive life change increased, and global self-esteem was associated with decreased injury time-loss when both negative life change and total life change increased. The results indicate that athletes with more optimism, hardiness or global self-esteem may cope more effectively with life change stress, resulting in reduced injury vulnerability and recovery rates.

  19. Hypothalamic-pituitary-adrenal axis genetic variation and early stress moderates amygdala function.

    Science.gov (United States)

    Di Iorio, Christina R; Carey, Caitlin E; Michalski, Lindsay J; Corral-Frias, Nadia S; Conley, Emily Drabant; Hariri, Ahmad R; Bogdan, Ryan

    2017-06-01

    Early life stress may precipitate psychopathology, at least in part, by influencing amygdala function. Converging evidence across species suggests that links between childhood stress and amygdala function may be dependent upon hypothalamic-pituitary-adrenal (HPA) axis function. Using data from college-attending non-Hispanic European-Americans (n=308) who completed the Duke Neurogenetics Study, we examined whether early life stress (ELS) and HPA axis genetic variation interact to predict threat-related amygdala function as well as psychopathology symptoms. A biologically-informed multilocus profile score (BIMPS) captured HPA axis genetic variation (FKBP5 rs1360780, CRHR1 rs110402; NR3C2 rs5522/rs4635799) previously associated with its function (higher BIMPS are reflective of higher HPA axis activity). BOLD fMRI data were acquired while participants completed an emotional face matching task. ELS and depression and anxiety symptoms were measured using the childhood trauma questionnaire and the mood and anxiety symptom questionnaire, respectively. The interaction between HPA axis BIMPS and ELS was associated with right amygdala reactivity to threat-related stimuli, after accounting for multiple testing (empirical-p=0.016). Among individuals with higher BIMPS (i.e., the upper 21.4%), ELS was positively coupled with threat-related amygdala reactivity, which was absent among those with average or low BIMPS. Further, higher BIMPS were associated with greater self-reported anxious arousal, though there was no evidence that amygdala function mediated this relationship. Polygenic variation linked to HPA axis function may moderate the effects of early life stress on threat-related amygdala function and confer risk for anxiety symptomatology. However, what, if any, neural mechanisms may mediate the relationship between HPA axis BIMPS and anxiety symptomatology remains unclear. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Avoidant coping moderates the relationship between paternal involvement in the child's type 1 diabetes (T1D) care and parenting stress.

    Science.gov (United States)

    Teasdale, Ashley; Limbers, Christine

    2018-01-01

    Fathers may experience greater parenting stress and anxiety when they are more involved in their child's type 1 diabetes (T1D) care. The present study evaluated whether seeking social support and avoidant coping strategies moderate the relationship between paternal involvement in the child's T1D care and parenting stress in an international sample. Two hundred forty-nine fathers of young children with T1D completed the Parenting Stress Index (PSI), Pediatric Inventory for Parents (PIP), Dads' Active Disease Support scale (DADS), COPE Inventory, Self-Care Inventory (SCI-R), and a demographic questionnaire online. Pearson's product moment correlations were computed, and multiple linear regression analysis was conducted with three separate models in which the PSI Child Domain, PIP Frequency, and PIP Difficulty scores represented different parenting stress outcomes. The interaction between use of denial coping and DADS Involvement was significantly correlated with general parenting stress ( p diabetes treatment regimen ( p management.

  1. The Consistent Kinetics Porosity (CKP) Model: A Theory for the Mechanical Behavior of Moderately Porous Solids

    Energy Technology Data Exchange (ETDEWEB)

    BRANNON,REBECCA M.

    2000-11-01

    A theory is developed for the response of moderately porous solids (no more than {approximately}20% void space) to high-strain-rate deformations. The model is consistent because each feature is incorporated in a manner that is mathematically compatible with the other features. Unlike simple p-{alpha} models, the onset of pore collapse depends on the amount of shear present. The user-specifiable yield function depends on pressure, effective shear stress, and porosity. The elastic part of the strain rate is linearly related to the stress rate, with nonlinear corrections from changes in the elastic moduli due to pore collapse. Plastically incompressible flow of the matrix material allows pore collapse and an associated macroscopic plastic volume change. The plastic strain rate due to pore collapse/growth is taken normal to the yield surface. If phase transformation and/or pore nucleation are simultaneously occurring, the inelastic strain rate will be non-normal to the yield surface. To permit hardening, the yield stress of matrix material is treated as an internal state variable. Changes in porosity and matrix yield stress naturally cause the yield surface to evolve. The stress, porosity, and all other state variables vary in a consistent manner so that the stress remains on the yield surface throughout any quasistatic interval of plastic deformation. Dynamic loading allows the stress to exceed the yield surface via an overstress ordinary differential equation that is solved in closed form for better numerical accuracy. The part of the stress rate that causes no plastic work (i.e-, the part that has a zero inner product with the stress deviator and the identity tensor) is given by the projection of the elastic stressrate orthogonal to the span of the stress deviator and the identity tensor.The model, which has been numerically implemented in MIG format, has been exercised under a wide array of extremal loading and unloading paths. As will be discussed in a companion

  2. Fibromyalgia: anti-inflammatory and stress responses after acute moderate exercise.

    Science.gov (United States)

    Bote, Maria Elena; Garcia, Juan Jose; Hinchado, Maria Dolores; Ortega, Eduardo

    2013-01-01

    Fibromyalgia (FM) is characterized in part by an elevated inflammatory status, and "modified exercise" is currently proposed as being a good therapeutic help for these patients. However, the mechanisms involved in the exercise-induced benefits are still poorly understood. The objective was to evaluate the effect of a single bout of moderate cycling (45 min at 55% VO2 max) on the inflammatory (serum IL-8; chemotaxis and O2 (-) production by neutrophils; and IL-1β, TNF-α, IL-6, IL-10, and IL-18 release by monocytes) and stress (cortisol; NA; and eHsp72) responses in women diagnosed with FM compared with an aged-matched control group of healthy women (HW). IL-8, NA, and eHsp72 were determined by ELISA. Cytokines released by monocytes were determined by Bio-Plex® system (LUMINEX). Cortisol was determined by electrochemoluminiscence, chemotaxis was evaluated in Boyden chambers and O2 (-) production by NBT reduction. In the FM patients, the exercise induced a decrease in the systemic concentration of IL-8, cortisol, NA, and eHsp72; as well as in the neutrophil's chemotaxis and O2 (-) production and in the inflammatory cytokine release by monocytes. This was contrary to the completely expected exercise-induced increase in all those biomarkers in HW. In conclusion, single sessions of moderate cycling can improve the inflammatory status in FM patients, reaching values close to the situation of aged-matched HW at their basal status. The neuroendocrine mechanism seems to be an exercise-induced decrease in the stress response of these patients.

  3. Fibromyalgia: anti-inflammatory and stress responses after acute moderate exercise.

    Directory of Open Access Journals (Sweden)

    Maria Elena Bote

    Full Text Available Fibromyalgia (FM is characterized in part by an elevated inflammatory status, and "modified exercise" is currently proposed as being a good therapeutic help for these patients. However, the mechanisms involved in the exercise-induced benefits are still poorly understood. The objective was to evaluate the effect of a single bout of moderate cycling (45 min at 55% VO2 max on the inflammatory (serum IL-8; chemotaxis and O2 (- production by neutrophils; and IL-1β, TNF-α, IL-6, IL-10, and IL-18 release by monocytes and stress (cortisol; NA; and eHsp72 responses in women diagnosed with FM compared with an aged-matched control group of healthy women (HW. IL-8, NA, and eHsp72 were determined by ELISA. Cytokines released by monocytes were determined by Bio-Plex® system (LUMINEX. Cortisol was determined by electrochemoluminiscence, chemotaxis was evaluated in Boyden chambers and O2 (- production by NBT reduction. In the FM patients, the exercise induced a decrease in the systemic concentration of IL-8, cortisol, NA, and eHsp72; as well as in the neutrophil's chemotaxis and O2 (- production and in the inflammatory cytokine release by monocytes. This was contrary to the completely expected exercise-induced increase in all those biomarkers in HW. In conclusion, single sessions of moderate cycling can improve the inflammatory status in FM patients, reaching values close to the situation of aged-matched HW at their basal status. The neuroendocrine mechanism seems to be an exercise-induced decrease in the stress response of these patients.

  4. Enhanced Thermostability of Arabidopsis Rubisco activase improves photosynthesis and growth rates under moderate heat stress.

    Science.gov (United States)

    Kurek, Itzhak; Chang, Thom Kai; Bertain, Sean M; Madrigal, Alfredo; Liu, Lu; Lassner, Michael W; Zhu, Genhai

    2007-10-01

    Plant photosynthesis declines when the temperature exceeds its optimum range. Recent evidence indicates that the reduction in photosynthesis is linked to ribulose-1,5-bis-phosphate carboxylase/oxygenase (Rubisco) deactivation due to the inhibition of Rubisco activase (RCA) under moderately elevated temperatures. To test the hypothesis that thermostable RCA can improve photosynthesis under elevated temperatures, we used gene shuffling technology to generate several Arabidopsis thaliana RCA1 (short isoform) variants exhibiting improved thermostability. Wild-type RCA1 and selected thermostable RCA1 variants were introduced into an Arabidopsis RCA deletion (Deltarca) line. In a long-term growth test at either constant 26 degrees C or daily 4-h 30 degrees C exposure, the transgenic lines with the thermostable RCA1 variants exhibited higher photosynthetic rates, improved development patterns, higher biomass, and increased seed yields compared with the lines expressing wild-type RCA1 and a slight improvement compared with untransformed Arabidopsis plants. These results provide clear evidence that RCA is a major limiting factor in plant photosynthesis under moderately elevated temperatures and a potential target for genetic manipulation to improve crop plants productivity under heat stress conditions.

  5. Parenting stress and child physical health among a low-income sample: The moderating role of child anxiety.

    Science.gov (United States)

    Kidwell, Katherine M; Nelson, Timothy D; Van Dyk, Tori

    2015-11-01

    This study examined child anxiety as a potential moderator of the relationship between parenting stress and child physical health. Low-income youth (N = 109, M = 9.51 years old) and their parents completed measures of anxiety, health-related quality of life, and parenting stress in an outpatient clinic. As an objective measure of physical health, medical service utilization was extracted from medical records. Parenting stress was associated significantly with worse health-related quality of life and higher service utilization. Child anxiety moderated the relationship between stress and health. Health psychologists should target both family stress and child anxiety in promoting better health outcomes among low-income families. © The Author(s) 2013.

  6. Work satisfaction and posttraumatic growth 1 year after the 2008 Wenchuan earthquake: the perceived stress as a moderating factor.

    Science.gov (United States)

    Xu, Jiuping; Wu, Wei

    2014-06-01

    This study investigated the role of perceived stress as a possible moderating factor between posttraumatic growth (PTG) and work satisfaction. A stratified random sampling strategy was used to survey 2080 adult survivors of the 2008 Sichuan earthquake. The Posttraumatic Growth Inventory, the Job Satisfaction Index Scale and the Perceived Stress Scale were used in the assessment of the posttraumatic growth, work satisfaction and perceived stress respectively, and hierarchical multiple regression analyses were used for the analysis. The findings highlight work satisfaction as an important factor in both the prediction of posttraumatic growth and for its moderating effect on perceived stress. Some demographic characteristics, such as gender, education level, and housing condition were found to also affect the survivors' posttraumatic growth. This conclusion indicates that managers should pay closer attention to their employees' psychological state after a disaster and medical practitioners should consider survivors' work status and perceived stress when dispensing mental health care. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Conscientiousness Moderates the Relationship Between Perceived Stress and Depressive Symptoms Among U.S. Chinese Older Adults.

    Science.gov (United States)

    Chen, Yiwei; Peng, Yisheng; Ma, Xiaodong; Dong, Xinqi

    2017-07-01

    The present study examined whether individuals' personality traits, Neuroticism and Conscientiousness, moderated the relationship between perceived stress and depressive symptoms among U.S. Chinese older adults. Data analysis was based on the Population Study of Chinese Elderly in Chicago (PINE). Three thousand one hundred and fifty-nine Chinese adults aged 60 years and older participated in the PINE study. They completed scales that assessed their personality (ie, Neuroticism and Conscientiousness of the NEO Five-Factor Inventory), perceived stress (the Chinese Perceived Stress Scale), and depressive symptoms (the Patient Health Questionnaire). Perceived stress was positively related to depressive symptoms among U.S. Chinese older adults. No moderation effects were found for Neuroticism. Conscientiousness significantly moderated the perceived stress-depressive symptom relationship. The positive relationship between perceived stress and depressive symptoms was weaker for people who were higher in Conscientiousness than those who were lower in Conscientiousness. Conscientiousness mitigated the stress-depressive symptom relationship among U.S. Chinese older adults. Future research is needed to identify the psychological and sociocultural profiles of individuals who show stress resilience and those who are vulnerable. Social services and psychological interventions are needed to promote health and well-being among U.S. Chinese older adults. © The Author 2017. 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.

  8. Transient Moderator Simulation Using CFX10-CAMO, a CANDU Moderator Analysis Model Based on a Coupled Solver

    International Nuclear Information System (INIS)

    Yoon, Churl; Park, Joo Hwan

    2007-01-01

    When a PHT(Primary Heat Transfer) system fails to remove excess heat from fuel channels for some loss of coolant accidents(LOCA's) in CANDU NPP's, the fuel channel temperature could increase until the pressure tube strains (i.e., balloon or sag) to contact its surrounding Calandria tube.(PT/CT contact) Following a PT/CT contact, there is a spike in the heat flux to the moderator surrounding the Calandria tube, which may lead to a sustained CT dryout and also a failure of a fuel channel. The prevention of a CT dryout following a PT/CT contact depends on the local moderator subcooling. That is, fuel channel integrity depends on the capability of the moderator to act as the ultimate heat sink for some LOCA's in a CANDU reactor. In KAERI, Yoon et al. developed a CFD model for predicting a CANDU-6 moderator temperature on the basis of a commercial CFD code CFX-4(ANSYS Inc.). This analytic model has the strength of modelling the hydraulic resistances in the core region and accounting for a heat source term in the energy equations. But convergence difficulties and a slow computing speed are the limitations of this model, because the CFX-4 code adapts a segregated solver to resolve a moderator circulation including a strong coupled-effect. Compared to a segregated solver, a coupled-solver is highly efficient and robust especially for a flow with a strong interference between the variables such as combustion

  9. Stress field models from Maxwell stress functions: southern California

    Science.gov (United States)

    Bird, Peter

    2017-08-01

    The lithospheric stress field is formally divided into three components: a standard pressure which is a function of elevation (only), a topographic stress anomaly (3-D tensor field) and a tectonic stress anomaly (3-D tensor field). The boundary between topographic and tectonic stress anomalies is somewhat arbitrary, and here is based on the modeling tools available. The topographic stress anomaly is computed by numerical convolution of density anomalies with three tensor Green's functions provided by Boussinesq, Cerruti and Mindlin. By assuming either a seismically estimated or isostatic Moho depth, and by using Poisson ratio of either 0.25 or 0.5, I obtain four alternative topographic stress models. The tectonic stress field, which satisfies the homogeneous quasi-static momentum equation, is obtained from particular second derivatives of Maxwell vector potential fields which are weighted sums of basis functions representing constant tectonic stress components, linearly varying tectonic stress components and tectonic stress components that vary harmonically in one, two and three dimensions. Boundary conditions include zero traction due to tectonic stress anomaly at sea level, and zero traction due to the total stress anomaly on model boundaries at depths within the asthenosphere. The total stress anomaly is fit by least squares to both World Stress Map data and to a previous faulted-lithosphere, realistic-rheology dynamic model of the region computed with finite-element program Shells. No conflict is seen between the two target data sets, and the best-fitting model (using an isostatic Moho and Poisson ratio 0.5) gives minimum directional misfits relative to both targets. Constraints of computer memory, execution time and ill-conditioning of the linear system (which requires damping) limit harmonically varying tectonic stress to no more than six cycles along each axis of the model. The primary limitation on close fitting is that the Shells model predicts very sharp

  10. Social Support and Relationship Satisfaction as Moderators of the Stress-Mood-Alcohol Link Association in US Navy Members.

    Science.gov (United States)

    Kelley, Michelle L; Milletich, Robert J; Hollis, Brittany F; Veprinsky, Anna; Robbins, Allison T; Snell, Alicia K

    2017-02-01

    The present study examined associations between stress and problematic alcohol use among US Navy members anticipating deployment, whether depressive symptoms mediated the stress-alcohol link, and whether social support and relationship satisfaction moderated associations between stress, depressive symptoms, and problematic alcohol use. Participants were 108 US Navy members assigned to an Arleigh Burke-class destroyer anticipating an 8-month deployment after Operational Enduring Freedom/Operation Iraqi Freedom. Stress was indirectly related to problematic alcohol use such that higher levels of stress were associated with higher levels of depressive symptoms, which were further associated with higher levels of alcohol use. The indirect effect of stress to problematic alcohol use via depressive symptoms was tested at different levels of social support and relationship satisfaction. At higher levels of social support and relationship satisfaction, the association between stress and problematic alcohol use via depressive symptoms decreased. Results help identify targets for alcohol prevention efforts among current military members.

  11. Cortisol responses to chronic stress in adult macaques: moderation by a polymorphism in the serotonin transporter gene.

    Science.gov (United States)

    Qin, Dongdong; Rizak, Joshua; Feng, Xiaoli; Yang, Shangchuan; Yang, Lichuan; Fan, Xiaona; Lü, Longbao; Chen, Lin; Hu, Xintian

    2015-02-01

    Accumulating evidence has shown that a polymorphism in the promoter region of the serotonin transporter gene (5-HTTLPR) moderates the association between stress and depressive symptoms. However, the exact etiologies underlying this moderation are not well understood. Here it is reported that among adult female rhesus macaques, an orthologous polymorphism (rh5-HTTLPR) exerted an influence on cortisol responses to chronic stress. It was found that females with two copies of the short allele were associated with increased cortisol responses to chronic stress in comparison to their counterparts who have one or two copies of the long allele. In the absence of stress, no differences related to genotype were observed in these females. This genetic moderation was found without a genetic influence on exposure to stressful situations. Rather it was found to be a genetic modulation of cortisol responses to chronic stress. These findings indicate that the rh5-HTTLPR polymorphism is closely related to hypothalamus-pituitary-adrenal (HPA) axis reactivity, which may increase susceptibility to depression in females with low serotonin transporter efficiency and a history of stress. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Moderately thin advertising models are optimal, most of the time: Moderation of the quadratic effect of model body-size on ad attitude by fashion leadership

    NARCIS (Netherlands)

    Janssen, D.M.; Paas, L.J.

    2014-01-01

    The authors hypothesize and find that an advertising model's body size has an inverted U-shaped relationship with ad attitude in the apparel product category, in which moderately thin advertising models are optimal. They assess the moderating effect of consumers' fashion leadership on this quadratic

  13. Stress-induced and cue-induced craving for alcohol in heavy drinkers: Preliminary evidence of genetic moderation by the OPRM1 and CRH-BP genes.

    Science.gov (United States)

    Ray, Lara A

    2011-01-01

    Neurobiological theories of addiction have highlighted disruption in stress pathways as a central feature of addictive disorders, and pharmacological treatments targeting stress mechanisms hold great promise. This study examines genetic determinants of stress-induced and cue-induced craving in heavy drinkers by testing single-nucleotide polymorphisms (SNPs) of the corticotrophin-releasing hormone binding protein (CRH-BP) gene and the mu-opioid receptor (OPRM1) gene. This study combines guided imagery stress exposure and in vivo alcohol cue exposure in a sample of 64 (23 women) non-treatment-seeking heavy drinkers. Analyses, uncorrected for multiple comparisons, revealed that a tag SNP of the CRH-BP gene (rs10055255) moderated stress-induced craving in this sample. The same SNP predicted greater affective responses to the stress manipulation, including greater levels of subjective tension and negative mood. The Asp40 allele of the OPRM1 was associated with greater cue-induced alcohol craving following the neutral imagery condition. These initial results extend recent preclinical and clinical findings implicating the CRH-BP in stress-related alcoholism and confirm the role of the Asp40 allele of the OPRM1 gene in reward-driven alcohol phenotypes. Human laboratory models of stress and cue-induced craving may be useful in pharmacotherapy development targeting dysregulation of stress systems. Larger studies are needed to validate these preliminary findings, which should also be extended to clinical samples. Copyright © 2010 by the Research Society on Alcoholism.

  14. Testing direct and moderating effects of coping styles on the relationship between perceived stress and antenatal anxiety symptoms.

    Science.gov (United States)

    Lau, Ying; Wang, Yuqiong; Kwong, Dennis Ho Keung; Wang, Ying

    2015-01-01

    The objective of this study was to test the direct and moderating effects of different coping styles in mitigating perceived stress associated with antenatal anxiety symptoms among 755 pregnant women in Chengdu. A cross-sectional study using a questionnaire survey was carried out. The Perceived Stress Scale, the Trait Coping Style Questionnaire and the Zung Self-rating Anxiety Scale were used to measure stress, coping and anxiety symptoms, respectively. Hierarchical regression analysis was used to test the direct and moderating effects of coping styles in the relationship between perceived stress and antenatal anxiety symptoms. Direct effects of negative coping (NC) styles were found. Women with higher NC scores were more likely to have anxiety symptoms. Positive coping (PC) styles had moderating effects on perceived stress, whereas NC styles did not. The findings of this study highlight the direct and moderating effects of coping styles. This knowledge is important to healthcare professionals in planning health service provision. Health services should dedicate resources to teaching pregnant women how to enhance PC styles, alter NC styles and cultivate optimistic thinking to alleviate anxiety symptoms.

  15. Kinetics model of bainitic transformation with stress

    Science.gov (United States)

    Zhou, Mingxing; Xu, Guang; Hu, Haijiang; Yuan, Qing; Tian, Junyu

    2018-01-01

    Thermal simulations were conducted on a Gleeble 3800 simulator. The main purpose is to investigate the effects of stress on the kinetics of bainitic transformation in a Fe-C-Mn-Si advanced high strength bainitic steel. Previous studies on modeling the kinetics of stress affected bainitic transformation only considered the stress below the yield strength of prior austenite. In the present study, the stress above the yield strength of prior austenite is taken into account. A new kinetics model of bainitic transformation dependent on the stress (including the stresses below and above the yield strength of prior austenite) and the transformation temperature is proposed. The new model presents a good agreement with experimental results. In addition, it is found that the acceleration degree of stress on bainitic transformation increases with the stress whether its magnitude is below or above the yield strength of austenite, but the increasing rate gradually slows down when the stress is above the yield strength of austenite.

  16. Cognitive moderators of children's adjustment to stressful divorce events: the role of negative cognitive errors and positive illusions.

    Science.gov (United States)

    Mazur, E; Wolchik, S A; Virdin, L; Sandler, I N; West, S G

    1999-01-01

    This study examined whether children's cognitive appraisal biases moderate the impact of stressful divorce-related events on psychological adjustment in 355 children ages 9 to 12, whose families had experienced divorce within the past 2 years. Multiple regression indicated that endorsement of negative cognitive errors for hypothetical divorce events moderates the relations between stressful divorce events and self- and maternal reports of internalizing and externalizing symptoms, but only for older children. Positive illusions buffer the effects of stressful divorce events on child-reported depression and mother-reported externalizing problems. Implications of these results for theories of stress and coping, as well as for interventions for children of divorced families, are discussed.

  17. Does substance use moderate the association of neighborhood disadvantage with perceived stress and safety in the activity spaces of urban youth?

    Science.gov (United States)

    Mennis, Jeremy; Mason, Michael; Light, John; Rusby, Julie; Westling, Erika; Way, Thomas; Zahakaris, Nikola; Flay, Brian

    2016-08-01

    This study investigates the association of activity space-based exposure to neighborhood disadvantage with momentary perceived stress and safety, and the moderation of substance use on those associations, among a sample of 139 urban, primarily African American, adolescents. Geospatial technologies are integrated with Ecological Momentary Assessment (EMA) to capture exposure to neighborhood disadvantage and perceived stress and safety in the activity space. A relative neighborhood disadvantage measure for each subject is calculated by conditioning the neighborhood disadvantage observed at the EMA location on that of the home neighborhood. Generalized estimating equations (GEE) are used to model the effect of relative neighborhood disadvantage on momentary perceived stress and safety, and the extent to which substance use moderates those associations. Relative neighborhood disadvantage is significantly associated with higher perceived stress, lower perceived safety, and greater substance use involvement. The association of relative neighborhood disadvantage with stress is significantly stronger among those with greater substance use involvement. This research highlights the value of integrating geospatial technologies with EMA and developing personalized measures of environmental exposure for investigating neighborhood effects on substance use, and suggests substance use intervention strategies aimed at neighborhood conditions. Future research should seek to disentangle the causal pathways of influence and selection that relate neighborhood environment, stress, and substance use, while also accounting for the role of gender and family and peer social contexts. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  18. Mediator or moderator? The role of mindfulness in the association between child behavior problems and parental stress.

    Science.gov (United States)

    Chan, Tim Oi; Lam, Shui-Fong

    2017-11-01

    Raising a child with intellectual disability (ID) may be stressful for parents. Previous studies have suggested the mediating role of mindfulness in the association between child behavior problems and parental stress. The present study examined whether this mediating role is a result of parents' self-report bias. It also explored whether mindfulness has a moderating role instead when child behavior problems are reported by teachers. In a questionnaire survey, 271 Chinese parents of children with ID in 6 Hong Kong special schools reported their levels of stress and mindfulness, as well as their children's behavior problems. The latter was also reported by teachers. When child behavior problems were reported by parents, parental mindfulness was a mediator between child behavior problems and parental stress. In contrast, when child behavior problems were reported by teachers, parental mindfulness was a moderator between child behavior problems and parental stress. The mediation role of mindfulness maybe an artifact of measurement. The findings provide an encouraging message that parenting a child with ID and behavior problems does not necessarily mean more stress among all parents. Parents with a high level of mindfulness may experience less stress than those with a low level of mindfulness. Parents of children with intellectual disability (ID) tend to report high psychological stress. Previous self-report studies have identified mindfulness as a mediator in the association between child behavior problems and parental stress. The present study differs from previous studies by including third-party's reports. It has contributed to the existing body of knowledge in two respects. First, it examined whether the mediation effect resulted from parent self-report bias. Second, it tested an alternative hypothesis of the moderation effect by using teachers' reports to measure child behavior problems. The results showed that when child behavior problems were measured by parents

  19. Partner Accommodation Moderates Treatment Outcomes for Couple Therapy for Posttraumatic Stress Disorder

    Science.gov (United States)

    Fredman, Steffany J.; Pukay-Martin, Nicole D.; Macdonald, Alexandra; Wagner, Anne C.; Vorstenbosch, Valerie; Monson, Candice M.

    2015-01-01

    Objective Partner accommodation of posttraumatic stress disorder (PTSD) symptoms (i.e., altering one’s own behaviors to minimize patient distress and/or relationship conflict due to patients’ PTSD symptoms) has been shown to be positively associated with patient and partner psychopathology and negatively associated with patient and partner relationship satisfaction cross-sectionally. However, the prognostic value of partner accommodation in treatment outcomes is unknown. The goals of the present study were to determine if partner accommodation decreases as a function of couple therapy for PTSD and if pretreatment partner accommodation moderates the efficacy of couple therapy for PTSD. Method Thirty-nine patients with PTSD and their intimate partners (n = 39) were enrolled in a randomized controlled trial of cognitive-behavioral conjoint therapy (CBCT) for PTSD (Monson & Fredman, 2012) and received CBCT for PTSD immediately or after three months of waiting. Blinded assessors determined clinician-rated PTSD symptoms and patient-rated PTSD and depressive symptoms and relationship satisfaction at baseline, mid-treatment/4 weeks of waiting, and posttreatment/12 weeks of waiting. Results Contrary to expectation, partner accommodation levels did not change over time for either treatment condition. However, baseline partner accommodation significantly moderated treatment outcomes. Higher levels of partner accommodation were associated with greater improvements in PTSD, depressive symptoms, and relationship satisfaction among patients receiving CBCT for PTSD compared with waiting list. At lower levels of partner accommodation, patients in both groups improved or remained at low levels of these outcomes. Conclusions Individuals with PTSD who have more accommodating partners may be particularly well-suited for couple therapy for PTSD. PMID:26501498

  20. STRESS RESPONSE STUDIES USING ANIMAL MODELS

    Science.gov (United States)

    This presentation will provide the evidence that ozone exposure in animal models induce neuroendocrine stress response and this stress response modulates lung injury and inflammation through adrenergic and glucocorticoid receptors.

  1. The link between perceived human resource management practices, engagement and employee behaviour : A moderated mediation model

    NARCIS (Netherlands)

    Alfes, K.; Shantz, A.D.; Truss, C.; Soane, E.C.

    2013-01-01

    This study contributes to our understanding of the mediating and moderating processes through which human resource management (HRM) practices are linked with behavioural outcomes. We developed and tested a moderated mediation model linking perceived HRM practices to organisational citizenship

  2. Transcriptome analysis provides insights into hepatic responses to moderate heat stress in the rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Li, Yongjuan; Huang, Jinqiang; Liu, Zhe; Zhou, Yanjing; Xia, Binpeng; Wang, Yongjie; Kang, Yujun; Wang, Jianfu

    2017-07-01

    The rainbow trout is an economically important fish in the world. The limited stress tolerance of this species to high summer-like temperatures usually leads to mass mortality and great economic loss. However, there is limited information on the mechanisms underlying moderate heat responses in the liver of the rainbow trout. Here, we performed transcriptome profiling of rainbow trout liver under moderate heat stress by using the Hiseq™ 4000 sequencing platform. More than 277 million clean reads were obtained from 6 libraries and aligned against the rainbow trout genome. A total of 128 unique transcripts were differentially expressed in the liver under heat-stress and control conditions, many heat shock protein genes for thermoregulation and some novel genes involved in heat stress were identified. Nine of the differently expressed genes were further validated by qRT-PCR. Gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses revealed that several pathways, including those for protein metabolism, energy metabolism, and immune system, were influenced by heat stress. Moreover, an important protein-processing pathway in the endoplasmic reticulum (ER) was identified, and the key role of ER-associated degradation and function of calpain as an upstream regulator of apoptosis were confirmed under heat stress. The results of this study provide a comprehensive overview of heat stress-induced transcriptional patterns in rainbow trout liver and would be particularly useful for further studies on the molecular mechanisms underlying responses to heat stress in this species. Copyright © 2017. Published by Elsevier B.V.

  3. STRESS INDUCED OBESITY: LESSONS FROM RODENT MODELS OF STRESS

    Directory of Open Access Journals (Sweden)

    Zachary Robert Patterson

    2013-07-01

    Full Text Available Stress is defined as the behavioral and physiological responses generated in the face of, or in anticipation of, a perceived threat. The stress response involves activation of the sympathetic nervous system and recruitment of the hypothalamic-pituitary-adrenal (HPA axis. When an organism encounters a stressor (social, physical, etc., these endogenous stress systems are stimulated in order to generate a fight-or-flight response, and manage the stressful situation. As such, an organism is forced to liberate energy resources in attempt to meet the energetic demands posed by the stressor. A change in the energy homeostatic balance is thus required to exploit an appropriate resource and deliver useable energy to the target muscles and tissues involved in the stress response. Acutely, this change in energy homeostasis and the liberation of energy is considered advantageous, as it is required for the survival of the organism. However, when an organism is subjected to a prolonged stressor, as is the case during chronic stress, a continuous irregularity in energy homeostasis is considered detrimental and may lead to the development of metabolic disturbances such as cardiovascular disease, type II diabetes mellitus and obesity. This concept has been studied extensively using animal models, and the neurobiological underpinnings of stress induced metabolic disorders are beginning to surface. However, different animal models of stress continue to produce divergent metabolic phenotypes wherein some animals become anorexic and loose body mass while others increase food intake and body mass and become vulnerable to the development of metabolic disturbances. It remains unclear exactly what factors associated with stress models can be used to predict the metabolic outcome of the organism. This review will explore a variety of rodent stress models and discuss the elements that influence the metabolic outcome in order to further our understanding of stress

  4. Oxidative stress in elite athletes training at moderate altitude and at sea level.

    Science.gov (United States)

    León-López, Josefa; Calderón-Soto, Carmen; Pérez-Sánchez, Matías; Feriche, Belén; Iglesias, Xavier; Chaverri, Diego; Rodréguez, Ferran A

    2018-03-24

    Using a controlled parallel group longitudinal trial design, we investigated the effects of different training interventions on the prooxidant/antioxidant status of elite athletes: living and training at moderate altitude for 3 (Hi-Hi3) and 4 weeks (Hi-Hi), and for 4 weeks too, living high and training high and low (Hi-HiLo) and living and training at sea level (Lo-Lo). From 61 swimmers, 54 completed the study. Nitrites, carbonyls, and lipid peroxidation (LPO) levels were assessed in plasma. Enzymatic antioxidants glutathione peroxidase (GPx) and glutathione reductase (GRd), and non-enzymatic antioxidants total glutathione (GST), reduced glutathione (GSH) and oxidized glutathione (GSSG) were analysed in the erythrocyte fraction. At the end of the intervention, nitrites levels were similar in all altitude groups but higher than in the Lo-Lo controls (P = .02). Hi-HiLo had greater GPx activity than Hi-Hi and Hi-Hi3 during most of the intervention (P ≤ .001). GRd activity was higher in Lo-Lo than in Hi-Hi at the end of the training camp (P ≤ .001). All groups showed increased levels of LPO, except Lo-Lo, and carbonyls at the end of the study (P ≤ .001). Training at altitude for 3 or 4 weeks drives oxidative stress leading to cellular damage mainly by worsening the antioxidant capacities. The GSSG/GSH ratio appears to be related to perceived exertion and fatigue. The stronger antioxidant defence showed by the Hi-HiLo group suggests an inverse relationship between redox alterations and performance. Further studies are required to investigate the role of oxidative stress in acclimatization, performance, and health.

  5. The effect of acute moderate psychological stress on working memory-related neural activity is modulated by a genetic variation in catecholaminergic function in humans

    Directory of Open Access Journals (Sweden)

    Shaozheng eQin

    2012-05-01

    Full Text Available Acute stress has an important impact on higher-order cognitive functions supported by the prefrontal cortex (PFC such as working memory (WM. In rodents, such effects are mediated by stress-induced alterations in catecholaminergic signaling, but human data in support of this notion is lacking. A common variation in the gene encoding Catechol-O-methyltransferase (COMT is known to affect basal catecholaminergic availability and PFC functions. Here, we investigated whether this genetic variation (Val158Met modulates effects of stress on WM-related prefrontal activity in humans. In a counterbalanced crossover design, 41 healthy young men underwent functional Magnetic Resonance Imaging (fMRI while performing a numerical N-back WM task embedded in a stressful or neutral context. Moderate psychological stress was induced by a well-controlled procedure involving viewing strongly aversive (versus emotionally neutral movie material in combination with a self-referencing instruction. Acute stress resulted in genotype-dependent effects on WM performance and WM-related activation in the dorsolateral PFC, with a relatively negative impact of stress in COMT Met-homozygotes as opposed to a relatively positive effect in Val-carriers. A parallel interaction was found for WM-related deactivation in the anterior medial temporal lobe. Our findings suggest that individuals with higher baseline catecholaminergic availability (COMT Met-homozygotes appear to reach a supraoptimal state under moderate levels of stress. In contrast, individuals with lower baselines (Val-carriers may reach an optimal state. Thus, our data show that effects of acute stress on higher-order cognitive functions vary depending on catecholaminergic availability at baseline, and thereby corroborate animal models of catecholaminergic signaling that propose a non-linear relationship between catecholaminergic activity and prefrontal functions.

  6. Capital Structure: Target Adjustment Model and a Mediation Moderation Model with Capital Structure as Mediator

    OpenAIRE

    Abedmajid, Mohammed

    2015-01-01

    This study consists of two models. Model one is conducted to check if there is a target adjustment toward optimal capital structure, in the context of Turkish firm listed on the stock market, over the period 2003-2014. Model 2 captures the interaction between firm size, profitability, market value and capital structure using the moderation mediation model. The results of model 1 have shown that there is a partial adjustment of the capital structure to reach target levels. The results of...

  7. Specificity in mediated pathways by anxiety symptoms linking adolescent stress profiles to depressive symptoms: Results of a moderated mediation approach.

    Science.gov (United States)

    Anyan, Frederick; Bizumic, Boris; Hjemdal, Odin

    2018-03-01

    We investigated the specificity in mediated pathways that separately link specific stress dimensions through anxiety to depressive symptoms and the protective utility of resilience. Thus, this study goes beyond lumping together potential mediating and moderating processes that can explain the relations between stress and (symptoms of) psychopathology and the buffering effect of resilience. Ghanaian adolescents between 13 and 17 years (female = 285; male = 244) completed the Adolescent Stress Questionnaire (ASQ), Spielberger State Anxiety Inventory (STAI), Short Mood Feeling Questionnaire (SMFQ) and the Resilience Scale for Adolescents (READ). Independent samples t-test, multivariate analysis of covariance with follow-up tests and moderated mediation analyses were performed. Evidences were found for specificity in the associations between dimensions of adolescent stressors and depressive symptoms independent of transient anxiety. Transient anxiety partly accounted for the indirect effects of eight stress dimensions on depressive symptoms. Except stress of school attendance and school/leisure conflict, resilience moderated the indirect effects of specific stress dimensions on depressive symptoms. Results suggested differences in how Ghanaian adolescents view the various stress dimensions, and mediated pathways associated with anxiety and depressive symptoms. Use of cross-sectional data does not show causal process and temporal changes over time. Findings support and clarify the specificity in the interrelations and mediated pathways among dimensions of adolescent stress, transient anxiety, and depressive symptoms. Conditional process analyses shows that resilience does not only buffer direct, but also indirect psychological adversities. Interventions for good mental health may focus on low resilience subgroups in specific stress dimensions while minimizing transient anxiety. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. To stress or not to stress: a question of models.

    Science.gov (United States)

    Gray, J Megan; Chaouloff, Francis; Hill, Matthew N

    2015-01-05

    Stress research is a rapidly evolving field that encompasses numerous disciplines ranging from neuroscience to metabolism. With many new researchers migrating into the field, navigating the hows and whys of specific research questions can sometimes be enigmatic given the availability of so many models in the stress field. Additionally, as with every field, there are many seemingly minor experimental details that can have dramatic influences on data interpretation, although many of these are unknown to those not familiar with the field. The aim of this overview is to provide some suggestions and points to guide researchers moving into the stress field and highlight relevant methodological points that they should consider when choosing a model for stress and deciding how to structure a study. We briefly provide a primer on the basics of endpoint measurements in the stress field, factors to consider when choosing a model for acute stress, the difference between repeated and chronic stress, and importantly, influencing variables that modulate endpoints of analysis in stress work. Copyright © 2015 John Wiley & Sons, Inc.

  9. Coping Self-Efficacy and Academic Stress among Hispanic First-Year College Students: The Moderating Role of Emotional Intelligence

    Science.gov (United States)

    Watson, Joshua C.; Watson, April A.

    2016-01-01

    In this study, the authors examined the role that emotional intelligence plays in moderating the relationship between academic stress and coping self-efficacy among a sample of 125 Hispanic 1st-year college students enrolled at a medium-size, southern Hispanic-serving institution. Results of a 2-stage hierarchical multiple regression analysis…

  10. Financial Stress, Parenting Quality, and the Moderating Effect of Co-Parenting Alliance within the Marital Dissolution Population

    Science.gov (United States)

    Mao, Dung Minh

    2017-01-01

    In this study, the relationship between the perception of financial stress (measured by income inadequacy), parenting quality (measured by positive parenting, consistent discipline, and good supervision), and the moderating effect that cooperative co-parenting (measured by co-parenting alliance) were investigated within a sample of parents who…

  11. Self-reported Cognitive Biases Moderate the Associations Between Social Stress and Paranoid Ideation in a Virtual Reality Experimental Study

    NARCIS (Netherlands)

    Pot-Kolder, Roos; Veling, Wim; Counotte, Jacqueline; van der Gaag, Mark

    2017-01-01

    Introduction: Cognitive biases are associated with psychosis liability and paranoid ideation. This study investigated the moderating relationship between pre-existing self-reported cognitive biases and the occurrence of paranoid ideation in response to different levels of social stress in a virtual

  12. Impulsivity as a Moderator and Mediator between Life Stress and Pathological Gambling among Chinese Treatment-Seeking Gamblers

    Science.gov (United States)

    Tang, Catherine So-kum; Wu, Anise M. S.

    2012-01-01

    This study examined the role of impulsivity and its interplay with gambling correlates in influencing the severity of pathological gambling in Chinese societies. It also investigated the extent to which impulsivity would moderate and/or mediate the relationship between life stress and pathological gambling in 94 Chinese treatment-seeking gamblers.…

  13. Age As Moderator of Emotional Stroop Task Performance in Posttraumatic Stress Disorder (PTSD

    Directory of Open Access Journals (Sweden)

    Maksymilian Bielecki

    2017-09-01

    Full Text Available Emotional Stroop task (EST has been extensively used to investigate attentional processes in posttraumatic stress disorder (PTSD. Even though aging significantly changes the dynamics of emotion-cognition interactions, very little is known about its role in shaping EST performance in PTSD patients. In the present study we tested a uniquely large sample of motor vehicle accident victims. Data of 194 participants (75.3% female; mean age = 36.64 years, SD = 12.3 were included in the analysis, out of which 136 (70.1% were diagnosed with PTSD. Prior to the psychiatric assessment, participants completed the pictorial version of EST (neutral, positive, negative, and accidents photos were presented. Comparison of the PTSD and control groups revealed a specific increase in reaction times (RTs related to the exposure of trauma-related material. At the same time, previously unreported, moderating effects of age were also discovered. Older participants, in contrast to the younger group, showed no increase in RTs and interference scores in trials where accident photos were presented. Our study points to the key role of age as a previously understudied factor modifying EST performance in PTSD patients.

  14. Age As Moderator of Emotional Stroop Task Performance in Posttraumatic Stress Disorder (PTSD).

    Science.gov (United States)

    Bielecki, Maksymilian; Popiel, Agnieszka; Zawadzki, Bogdan; Sedek, Grzegorz

    2017-01-01

    Emotional Stroop task (EST) has been extensively used to investigate attentional processes in posttraumatic stress disorder (PTSD). Even though aging significantly changes the dynamics of emotion-cognition interactions, very little is known about its role in shaping EST performance in PTSD patients. In the present study we tested a uniquely large sample of motor vehicle accident victims. Data of 194 participants (75.3% female; mean age = 36.64 years, SD = 12.3) were included in the analysis, out of which 136 (70.1%) were diagnosed with PTSD. Prior to the psychiatric assessment, participants completed the pictorial version of EST (neutral, positive, negative, and accidents photos were presented). Comparison of the PTSD and control groups revealed a specific increase in reaction times (RTs) related to the exposure of trauma-related material. At the same time, previously unreported, moderating effects of age were also discovered. Older participants, in contrast to the younger group, showed no increase in RTs and interference scores in trials where accident photos were presented. Our study points to the key role of age as a previously understudied factor modifying EST performance in PTSD patients.

  15. Interpersonal trauma moderates the relationship between personality factors and suicidality of individuals with posttraumatic stress disorder.

    Science.gov (United States)

    Yoo, Yongjoon; Park, Hyeon-Ju; Park, Soowon; Cho, Maeng Je; Cho, Seong-Jin; Lee, Ji Yeon; Choi, Soo-Hee; Lee, Jun-Young

    2018-01-01

    Individuals with posttraumatic stress disorder (PTSD) are more prone to suicidal ideation and behavior. While those who have experienced interpersonal trauma exhibit more suicidality than those who have experienced non-interpersonal trauma, it is unclear how the traumatic effects are related to an individual's personality characteristics. This study examined the association between interpersonal trauma and personality factors with suicidality, and elucidated the moderating role of interpersonal trauma in individuals with PTSD. The study included 6,022 participants from the Korean Epidemiologic Catchment Area Study 2011. The Korean Version of Composite International Diagnostic Interview was used for the survey, including the participants' history of suicidality, the traumas they have experienced, and their PTSD symptoms. The 11-item version of the Big Five Inventory (BFI-11) was used to assess the participants' personality factors. 76 individuals were diagnosed with PTSD, while 810 had been exposed to trauma but were not diagnosed with any DSM-IV mental disorder. Among the individuals with PTSD, those who had experienced interpersonal trauma were more likely to have suicidal ideation than those who had experienced non-interpersonal trauma (p = .020; odds ratio [OR] = 3.643; 95% confidence interval of OR = [1.226, 10.825]). High agreeableness and conscientiousness predicted less suicidality in those exposed to non-interpersonal trauma, while predicting more suicidality in those exposed to interpersonal trauma. Clinicians examining individuals with PTSD should pay closer attention to the trauma that they have experienced, as well as their personality factors, to provide appropriate treatment.

  16. Work-family conflict and alcohol use: examination of a moderated mediation model.

    Science.gov (United States)

    Wolff, Jennifer M; Rospenda, Kathleen M; Richman, Judith A; Liu, Li; Milner, Lauren A

    2013-01-01

    Research consistently documents the negative effects of work-family conflict; however, little research focuses on alcohol use. This study embraces a tension reduction theory of drinking, wherein alcohol use is thought to reduce the negative effects of stress. The purpose of the study was to test a moderated mediation model of the relationship between work-family conflict and alcohol use in a Chicagoland community sample of 998 caregivers. Structural equation models showed that distress mediated the relationship between work-family conflict and alcohol use. Furthermore, tension reduction expectancies of alcohol exacerbated the relationship between distress and alcohol use. The results advance the study of work-family conflict and alcohol use, helping explain this complicated relationship using sophisticated statistical techniques. Implications for theory and practice are discussed.

  17. Does leisure time moderate or mediate the effect of daily stress on positive affect? An examination using eight-day diary data

    Science.gov (United States)

    Qian, Xinyi Lisa; Yarnal, Careen M.; Almeida, David M.

    2013-01-01

    This study tested the applicability of moderation and mediation models to leisure time as a stress coping resource. Analyzing eight-day diary data (N=2,022), we examined the within-person process of using leisure time to cope with daily stressors. We found that relatively high daily stress frequency, while reducing positive affect, prompted an individual to allocate more time to leisure than usual, which then increased positive affect, thus partially remedying the damage by high daily stress frequency. This within-person process, however, is significantly stronger among those with less leisure time on average than leisure-rich individuals. The findings support a partial counteractive mediation model, demonstrate between-person difference in the within-person coping process, and reveal the importance of positive affect as a coping outcome. PMID:25221350

  18. Does leisure time moderate or mediate the effect of daily stress on positive affect? An examination using eight-day diary data.

    Science.gov (United States)

    Qian, Xinyi Lisa; Yarnal, Careen M; Almeida, David M

    2014-01-01

    This study tested the applicability of moderation and mediation models to leisure time as a stress coping resource. Analyzing eight-day diary data (N=2,022), we examined the within -person process of using leisure time to cope with daily stressors. We found that relatively high daily stress frequency, while reducing positive affect, prompted an individual to allocate more time to leisure than usual, which then increased positive affect, thus partially remedying the damage by high daily stress frequency. This within-person process, however, is significantly stronger among those with less leisure time on average than leisure-rich individuals. The findings support a partial counteractive mediation model, demonstrate between-person difference in the within-person coping process, and reveal the importance of positive affect as a coping outcome.

  19. The Stress-Metabolic Syndrome Relationship in Adolescents: An Examination of the Moderating Potential of Physical Activity.

    Science.gov (United States)

    Holmes, Megan E; Pivarnik, Jim; Pfeiffer, Karin; Maier, Kimberly S; Eisenmann, Joey C; Ewing, Martha

    2016-10-01

    The role of psychosocial stress in the development of obesity and metabolic syndrome is receiving increased attention and has led to examination of whether physical activity may moderate the stress-metabolic syndrome relationship. The current study examined relationships among physical activity, stress, and metabolic syndrome in adolescents. Participants (N = 126; 57 girls, 69 boys) were assessed for anthropometry, psychosocial stress, physical activity, and metabolic syndrome variables; t tests were used to examine sex differences, and regression analysis was used to assess relationships among variables controlling for sex and maturity status. Mean body mass index approached the 75th percentile for both sexes. Typical sex differences were observed for systolic blood pressure, time spent in moderate and vigorous physical activity, and perceived stress. Although stress was not associated with MetS (β = -.001, P = .82), a modest, positive relationship was observed with BMI (β = .20, P = .04). Strong relationships between physical activity and stress with MetS or BMI were not found in this sample. Results may be partially explained by overall good physical health status of the participants. Additional research in groups exhibiting varying degrees of health is needed.

  20. Chronic family stress moderates the association between a TOMM40 variant and triglyceride levels in two independent Caucasian samples.

    Science.gov (United States)

    Jiang, Rong; Brummett, Beverly H; Hauser, Elizabeth R; Babyak, Michael A; Siegler, Ilene C; Singh, Abanish; Astrup, Arne; Pedersen, Oluf; Hansen, Torben; Holst, Claus; Sørensen, Thorkild I A; Williams, Redford B

    2013-04-01

    TOMM40 SNP rs157580 has been associated with triglyceride levels in genome-wide association studies (GWAS). Chronic caregiving stress moderates the association between triglyceride levels and a nearby SNP rs439401 that is associated with triglyceride levels in GWAS. Here, we report data from two independent Caucasian samples (242 U.S. women and men; 466 Danish men) testing the hypothesis that chronic family stress also moderates the association between rs157580 and triglyceride levels. The interaction of rs157580 and family stress in predicting triglyceride levels was statistically significant in the U.S. sample (p=0.004) and marginally significant (p=0.075) in the Danish sample. The G allele of rs157580 was associated with increased triglyceride levels among family stressed cases in both samples compared with A/A cases, but not among controls. Chronic family stress moderates the association of rs157580 variants with triglyceride levels and should be taken into account for disease risk assessment and potential intervention. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. The Moderator Role of Perceived Emotional Intelligence in the Relationship between Sources of Stress and Mental Health in Teachers.

    Science.gov (United States)

    Pulido-Martos, Manuel; Lopez-Zafra, Esther; Estévez-López, Fernando; Augusto-Landa, José María

    2016-03-03

    This study analyzes the role of Perceived Emotional Intelligence (PEI) on sources of job stress and mental health in 250 elementary school teachers from Jaén (Spain). The aim of the study was two-fold: (1) to analyze the associations between Perceived Emotional Intelligence (PEI), sources of occupational stress and mental health; and (2) to determine whether PEI moderates the relationship between sources of occupational stress and mental health. An initial sample of 250 teachers was assessed Three questionnaires, the Trait Meta-Mood Scale, the Sources of Stress Scale in Teachers and the Medical Outcomes Study 36-item Short Form Health Survey, were used to evaluate PEI, sources of occupational stress and mental health, respectively. Teachers with higher levels of emotional attention reported lower levels of mental health (r = -.30; p relationship between sources of occupational stress and emotional role. Specifically, each significant interaction (i.e., deficiencies x attention, adaptation x attention, and adaptation x clarity) made a small and unique contribution in the explanation of emotional role (all p < .05, all sr 2 ∼ .02). Finally, our results imply that PEI is an important moderator of teachers´ occupational stressors on mental health.

  2. Posttraumatic stress and worry as mediators and moderators between political stressors and emotional and behavioral disorders in Palestinian children.

    Science.gov (United States)

    Khamis, Vivian

    2012-01-01

    This study was designed to assess whether the symptoms of posttraumatic stress mediate or moderate the relationship between political stressors and emotional and behavioral disorders in Palestinian children. It was hypothesized that (a) posttraumatic stress and worry mediate the effect of political stressors on behavioral and emotional disorders and (b) the relationship between political stressors and behavioral and emotional disorders should be attenuated for children with low levels of worry and posttraumatic stress and strengthened for children with high levels of worry and posttraumatic stress. The total sample was 1267 school age children of both sexes with a mean age of 11.97 years. Interviews were conducted with children at school. As hypothesized, the results indicated that posttraumatic stress and worry mediated and moderated the relationship between political stressors and emotional and behavioral disorders in children. Cognitive-behavioral therapy may be used to reduce the incidence of posttraumatic stress and decrease self-reported worry, somatic symptoms, general anxiety, and depression among children exposed to political trauma. Cognitive-behavioral treatment that exclusively targets excessive worry can lead to clinical change in the other interacting subsystems at the cognitive, physiological, affective and behavioral levels.

  3. Interpersonal trauma moderates the relationship between personality factors and suicidality of individuals with posttraumatic stress disorder

    Science.gov (United States)

    Yoo, Yongjoon; Park, Hyeon-Ju; Park, Soowon; Cho, Maeng Je; Cho, Seong-Jin; Lee, Ji Yeon

    2018-01-01

    Individuals with posttraumatic stress disorder (PTSD) are more prone to suicidal ideation and behavior. While those who have experienced interpersonal trauma exhibit more suicidality than those who have experienced non-interpersonal trauma, it is unclear how the traumatic effects are related to an individual’s personality characteristics. This study examined the association between interpersonal trauma and personality factors with suicidality, and elucidated the moderating role of interpersonal trauma in individuals with PTSD. The study included 6,022 participants from the Korean Epidemiologic Catchment Area Study 2011. The Korean Version of Composite International Diagnostic Interview was used for the survey, including the participants’ history of suicidality, the traumas they have experienced, and their PTSD symptoms. The 11-item version of the Big Five Inventory (BFI-11) was used to assess the participants’ personality factors. 76 individuals were diagnosed with PTSD, while 810 had been exposed to trauma but were not diagnosed with any DSM-IV mental disorder. Among the individuals with PTSD, those who had experienced interpersonal trauma were more likely to have suicidal ideation than those who had experienced non-interpersonal trauma (p = .020; odds ratio [OR] = 3.643; 95% confidence interval of OR = [1.226, 10.825]). High agreeableness and conscientiousness predicted less suicidality in those exposed to non-interpersonal trauma, while predicting more suicidality in those exposed to interpersonal trauma. Clinicians examining individuals with PTSD should pay closer attention to the trauma that they have experienced, as well as their personality factors, to provide appropriate treatment. PMID:29329352

  4. Mindfulness may both moderate and mediate the effect of physical fitness on cardiovascular responses to stress: a speculative hypothesis

    Science.gov (United States)

    Demarzo, Marcelo M. P.; Montero-Marin, Jesús; Stein, Phyllis K.; Cebolla, Ausiàs; Provinciale, Jaime G.; García-Campayo, Javier

    2014-01-01

    The psychological construct of mindfulness refers to an awareness that emerges by intentionally paying attention to the present experience in a non-judgmental or evaluative way. This particular quality of awareness has been associated to several indicators of physical and psychological health, and can be developed using mindfulness-based interventions (MBIs), and therefore MBIs have been successfully applied as preventive and complementary interventions and therapies in medicine and psychology. Together with quiet sitting and lying meditation practices, mindful physical exercises such as “mindful walking” and “mindful movement” are key elements in MBIs and couple muscular activity with an internally directed focus, improving interoceptive attention to bodily sensations. In addition, MBIs seem to share similar mechanisms with physical fitness (PF) by which they may influence cardiovascular responses to stress. Based on these facts, it is feasible to raise the question of whether physical training itself may induce the development of that particular quality of awareness associated with mindfulness, or if one's dispositional mindfulness (DM) (the tendency to be more mindful in daily life) could moderate the effects of exercise on cardiovascular response to stress. The role of mindfulness as a mediator or moderator of the effect of exercise training on cardiovascular responses to stress has barely been studied. In this study, we have hypothesized pathways (moderation and mediation) by which mindfulness could significantly influence the effects of PF on cardiovascular responses to stress and discussed potential practical ways to test these hypotheses. PMID:24723891

  5. Mindfulness may both moderate and mediate the effect of physical fitness on cardiovascular responses to stress: a speculative hypothesis.

    Directory of Open Access Journals (Sweden)

    Marcelo Marcos Piva Demarzo

    2014-03-01

    Full Text Available The psychological construct of mindfulness refers to an awareness that emerges by intentionally paying attention to the present experience in a non-judgmental or evaluative way. This particular quality of awareness has been associated to several indicators of physical and psychological health, and can be developed using mindfulness-based interventions (MBIs, and therefore MBIs have been successfully applied as preventive and complementary interventions and therapies in medicine and psychology. Together with quiet sitting and lying meditation practices, mindful physical exercises such as mindful walking and mindful movement are key elements in MBIs and couple muscular activity with an internally directed focus, improving interoceptive attention to bodily sensations. In addition, MBIs seem to share similar mechanisms with physical fitness by which they may influence cardiovascular responses to stress. Based on these facts, it is feasible to raise the question of whether physical training itself may induce the development of that particular quality of awareness associated with mindfulness, or if one’s dispositional mindfulness (the tendency to be more mindful in daily life could moderate the effects of exercise on cardiovascular response to stress. The role of mindfulness as a mediator or moderator of the effect of exercise training on cardiovascular responses to stress has barely been studied. In this study, we have hypothesized pathways (moderation and mediation by which mindfulness could significantly influence the effects of physical fitness on cardiovascular responses to stress and have discuss potential practical ways to test these hypotheses.

  6. Mindfulness may both moderate and mediate the effect of physical fitness on cardiovascular responses to stress: a speculative hypothesis.

    Science.gov (United States)

    Demarzo, Marcelo M P; Montero-Marin, Jesús; Stein, Phyllis K; Cebolla, Ausiàs; Provinciale, Jaime G; García-Campayo, Javier

    2014-01-01

    The psychological construct of mindfulness refers to an awareness that emerges by intentionally paying attention to the present experience in a non-judgmental or evaluative way. This particular quality of awareness has been associated to several indicators of physical and psychological health, and can be developed using mindfulness-based interventions (MBIs), and therefore MBIs have been successfully applied as preventive and complementary interventions and therapies in medicine and psychology. Together with quiet sitting and lying meditation practices, mindful physical exercises such as "mindful walking" and "mindful movement" are key elements in MBIs and couple muscular activity with an internally directed focus, improving interoceptive attention to bodily sensations. In addition, MBIs seem to share similar mechanisms with physical fitness (PF) by which they may influence cardiovascular responses to stress. Based on these facts, it is feasible to raise the question of whether physical training itself may induce the development of that particular quality of awareness associated with mindfulness, or if one's dispositional mindfulness (DM) (the tendency to be more mindful in daily life) could moderate the effects of exercise on cardiovascular response to stress. The role of mindfulness as a mediator or moderator of the effect of exercise training on cardiovascular responses to stress has barely been studied. In this study, we have hypothesized pathways (moderation and mediation) by which mindfulness could significantly influence the effects of PF on cardiovascular responses to stress and discussed potential practical ways to test these hypotheses.

  7. A Behavioral Weight Reduction Model for Moderately Mentally Retarded Adolescents.

    Science.gov (United States)

    Rotatori, Anthony F.; And Others

    1980-01-01

    A behavioral weight reduction treatment and maintenance program for moderately mentally retarded adolescents which involves six phases from background information collection to followup relies on stimulus control procedures to modify eating behaviors. Data from pilot studies show an average weekly weight loss of .5 to 1 pound per S. (CL)

  8. Cognitive reserve and self-efficacy as moderators of the relationship between stress exposure and executive functioning among spousal dementia caregivers.

    Science.gov (United States)

    Pertl, M M; Hannigan, C; Brennan, S; Robertson, I H; Lawlor, B A

    2017-04-01

    A substantial literature has reported that stress negatively impacts on cognitive processes. As dementia caregiving can be stressful, it has been hypothesized that the challenges of dementia care may increase caregivers' own vulnerability to cognitive decline. Prefrontal processes are thought to be most vulnerable to stress; however, few studies have examined whether greater caregiver stress predicts poorer executive dysfunction, and no previous research has considered potential moderators of this relationship. We examined (1) whether greater psychological stress mediated a relationship between caregiver stress exposure and executive functioning and (2) whether greater self-efficacy and cognitive reserve (CR) moderated this relationship. Spousal dementia caregivers (n = 253) completed the Neuropsychiatric Inventory Questionnaire (stress exposure), the Perceived Stress Scale, the National Adult Reading Test (CR), the Fortinsky dementia-specific caregiver self-efficacy scale, and the Color Trails Test (executive functioning). Moderated mediation was tested using the PROCESS macro. Age, gender, and dementia risk factors were included as covariates. Greater stress exposure indirectly predicted executive functioning through psychological stress. Stronger relationships between greater psychological stress and poorer executive functioning were observed among caregivers with lower CR; there was no evidence that self-efficacy moderated the relationship between stress exposure and psychological stress. Our findings are in line with the idea that greater psychological stress in response to challenges associated with dementia care predicts poorer caregiver executive functioning, particularly among caregivers with low CR. However, these findings are cross sectional; it is also possible that poorer executive functioning contributes to greater caregiver stress.

  9. Genetic moderation of the association between adolescent romantic involvement and depression: Contributions of serotonin transporter gene polymorphism, chronic stress, and family discord

    OpenAIRE

    Starr, Lisa R.; Hammen, Constance

    2015-01-01

    Studies support a link between adolescent romantic involvement and depression. Adolescent romantic relationships may increase depression risk by introducing chronic stress, and genetic vulnerability to stress reactivity/emotion dysregulation may moderate these associations. We tested genetic moderation of longitudinal associations between adolescent romantic involvement and later depressive symptoms by a polymorphism in the serotonin transporter linked polymorphic region gene (5-HTTLPR), and ...

  10. Moderation and Assessment Project--South West. A Presentation of a Model for Moderating Pupils' Work That Is Teacher Assessed, Developed in England, UK.

    Science.gov (United States)

    Radnor, Hilary

    The Moderation and Assessment Project, South West, was an outgrowth of the Technical and Vocational Educational Initiative of the government of the United Kingdom that attempted to develop more courses with vocational relevance for adolescents. Growing from research projects under the Moderation and Assessment project, a new model of moderation is…

  11. Big Five Personality Traits and the General Factor of Personality as Moderators of Stress and Coping Reactions Following an Emergency Alarm on a Swiss University Campus.

    Science.gov (United States)

    Hengartner, Michael P; van der Linden, Dimitri; Bohleber, Laura; von Wyl, Agnes

    2017-02-01

    We conducted an online survey including 306 participants aged 18-64 years to assess the general factor of personality (GFP) and Big Five personality traits in relation to individual stress and coping reactions following a shooting emergency alarm at a Swiss university campus. Although the emergency eventually turned out to be a false alarm, various witnesses showed pronounced distress owing to a vast police operation. The GFP structure was replicated using two alternative modelling approaches. Neuroticism related substantially to acute fear and traumatic distress as well as to more enduring maladaptive coping. Agreeableness was negatively associated with the coping strategy of medication use, whereas both agreeableness and conscientiousness related positively to social activity following the emergency. The GFP related moderately to peri-traumatic distress and showed a substantial negative association with medication use and a strong positive association with social activity. In conclusion, both the GFP and Big Five traits significantly moderate stress responses following a stressful life event. The GFP predominantly relates to socially adaptive coping, whereas in particular neuroticism accounts for acute stress reactions such as fear and traumatic distress. These findings support the notion that personality influences how persons react in the face of adversity. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  12. Stressful life events, perceived stress, and 12-month course of geriatric depression: direct effects and moderation by the 5-HTTLPR and COMT Val158Met polymorphisms.

    Science.gov (United States)

    Zannas, Anthony S; McQuoid, Douglas R; Steffens, David C; Chrousos, George P; Taylor, Warren D

    2012-07-01

    Although the relation between stressful life events (SLEs) and risk of major depressive disorder is well established, important questions remain about the effects of stress on the course of geriatric depression. Our objectives were (1) to examine how baseline stress and change in stress is associated with course of geriatric depression and (2) to test whether polymorphisms of serotonin transporter (5-HTTLPR) and catechol-O-methyltransferase (COMT Val158Met) genes moderate this relation. Two-hundred and sixteen depressed subjects aged 60 years or older were categorized by remission status (Montgomery-Asberg depression rating scale≤6) at 6 and 12 months. At 6 months, greater baseline numbers of self-reported negative and total SLEs and greater baseline perceived stress severity were associated with lower odds of remission. At 12 months, only baseline perceived stress predicted remission. When we examined change in stress, 12-month decrease in negative SLEs and level of perceived stress were associated with improved odds of 12-month remission. When genotype data were included, COMT Val158Met genotype did not influence these relations. However, when compared with 5-HTTLPR L/L homozygotes, S allele carriers with greater baseline numbers of negative SLEs and with greater decrease in negative SLEs were more likely to remit at 12 months. This study demonstrates that baseline SLEs and perceived stress severity may influence the 12-month course of geriatric depression. Moreover, changes in these stress measures over time correlate with depression outcomes. 5-HTTLPR S carriers appear to be more susceptible to both the effects of enduring stress and the benefit of interval stress reduction.

  13. Workplace Bullying and Employee Outcomes: A Moderated Mediated Model

    OpenAIRE

    Sheehan, M.; McCabe, T J.; Garavan, Thomas.

    2018-01-01

    This paper investigates the relationship between workplace bullying and employee outcomes in a healthcare setting. Drawing on HR process theory, we investigate the mediating role of the perceived effectiveness of implementation of anti-bullying practices on employee outcomes and whether targeted line manager training was a moderator of that relationship. Our multi-level analysis (utilising responses from 1,507 employees within forty-seven hospitals with matched HR Director interviews), finds ...

  14. Psychological stress and musculoskeletal pain: the moderating effect of childhood and adulthood trauma

    OpenAIRE

    Woodward, April

    2015-01-01

    The aetiology of widespread musculoskeletal pain is complex. Psychological stress is a robust predictor of symptom onset and persistence but not everyone who experiences stress goes on to develop widespread pain. The aim of the studies presented in this thesis was to ascertain whether individuals with a history of trauma have an increased susceptibility to widespread pain when they experience psychological stress; to identify psychosocial mediators of the stress pain relationship, and ascerta...

  15. Pre-treatment social anxiety severity moderates the impact of mindfulness-based stress reduction and aerobic exercise.

    Science.gov (United States)

    Jazaieri, Hooria; Lee, Ihno A; Goldin, Philippe R; Gross, James J

    2016-06-01

    We examined whether social anxiety severity at pre-treatment would moderate the impact of mindfulness-based stress reduction (MBSR) or aerobic exercise (AE) for generalized social anxiety disorder. MBSR and AE produced equivalent reductions in weekly social anxiety symptoms. Improvements were moderated by pre-treatment social anxiety severity. Mindfulness-based stress reduction (MBSR) and aerobic exercise (AE) are effective in reducing symptoms of social anxiety. Pre-treatment social anxiety severity can be used to inform treatment recommendations. Both MBSR and AE produced equivalent reductions in weekly levels of social anxiety symptoms. MBSR appears to be most effective for patients with lower pre-treatment social anxiety symptom severity. AE appears to be most effective for patients with higher pre-treatment social anxiety symptom severity. © 2015 The British Psychological Society.

  16. Moderators of Coronary Vasomotion during Mental Stress in Coronary Artery Disease Patients: Stress Reactivity, Serum Lipoproteins, and Severity of Atherosclerosis

    National Research Council Canada - National Science Library

    Howell, Robert H

    1996-01-01

    Impaired coronary artery vasomotion in response to behavioral triggers such as mental stress may be an important pathophysiological process involved in acute manifestations of coronary artery disease...

  17. Stress-related clinical pain and mood in women with chronic pain: moderating effects of depression and positive mood induction.

    Science.gov (United States)

    Davis, Mary C; Thummala, Kirti; Zautra, Alex J

    2014-08-01

    Chronic pain with comorbid depression is characterized by poor mood regulation and stress-related pain. This study aims to compare depressed and non-depressed pain patients in mood and pain stress reactivity and recovery, and test whether a post-stress positive mood induction moderates pain recovery. Women with fibromyalgia and/or osteoarthritis (N = 110) underwent interpersonal stress and were then randomly assigned by pain condition and depression status, assessed via the Center for Epidemiological Studies-Depression scale, to positive versus neutral mood induction. Depression did not predict stress-related reactivity in despondency, joviality, or clinical pain. However, depression × mood condition predicted recovery in joviality and clinical pain; depressed women recovered only in the positive mood condition, whereas non-depressed women recovered in both mood conditions. Depression does not alter pain and mood stress reactivity, but does impair recovery. Boosting post-stress jovial mood ameliorates pain recovery deficits in depressed patients, a finding relevant to chronic pain interventions.

  18. Transactional Associations between Youths' Responses to Peer Stress and Depression: The Moderating Roles of Sex and Stress Exposure

    Science.gov (United States)

    Agoston, Anna M.; Rudolph, Karen D.

    2011-01-01

    This study examined transactional associations between responses to peer stress and depression in youth. Specifically, it tested the hypotheses that (a) depression would predict fewer effortful responses and more involuntary, dysregulated responses to peer stress over time; and (b) fewer adaptive and more maladaptive responses would predict…

  19. Modelling of an experiment INSS and paraffin moderator at JINR

    International Nuclear Information System (INIS)

    Goyal, Uttam; Kumawat, Harphool; Kumar, V.; Barashenkov, V.S.

    2002-01-01

    Intense neutron spallation source (INSS) described elsewhere is studied with paraffin moderator using the Dubna cascade code. For the present study paraffin is assumed having configuration corresponding to C 22 H 46 with density = 0.87 g/cm 3 6 cm thickness of paraffin is coated around the Pb-spallation target of size ΦxL = 8x20 cm 2 and proton beam with E lab = 1 GeV is allowed to collide at the center of the left face

  20. Anxiety, Affect, Self-Esteem, and Stress: Mediation and Moderation Effects on Depression

    OpenAIRE

    Nima, Ali Al; Rosenberg, Patricia; Archer, Trevor; Garcia, Danilo

    2013-01-01

    Background Mediation analysis investigates whether a variable (i.e., mediator) changes in regard to an independent variable, in turn, affecting a dependent variable. Moderation analysis, on the other hand, investigates whether the statistical interaction between independent variables predict a dependent variable. Although this difference between these two types of analysis is explicit in current literature, there is still confusion with regard to the mediating and moderating effects of differ...

  1. Social support as moderator of the stress on unemployed people’s health

    OpenAIRE

    Guarino, Leticia Rosaria; Universidad Simón Bolívar; Sojo, Victor; Universidad Central de Venezuela, Caracas

    2011-01-01

    The aim of this research was to assess moderating role of two indexes of social support in the relationship between the length of unemployment and the physical and mental health of Venezuelan unemployed. Self-report measures were administered to a sample of 328 unemployed residents in Caracas, Venezuela. Results indicated that perceived social support acted as moderator in predicting better general health and lower somatization in the unemployed, acting as buffer of longer periods of unemploy...

  2. Predictors of Emotional Eating during Adolescents' Transition to College: Does Body Mass Index Moderate the Association between Stress and Emotional Eating?

    Science.gov (United States)

    Wilson, Shana M.; Darling, Katherine E.; Fahrenkamp, Amy J.; D'Auria, Alexandra L.; Sato, Amy F.

    2015-01-01

    Objective: This study sought to (1) examine perceived stress and resources to cope with stress as predictors of emotional eating during the transition to college and (2) determine whether body mass index (BMI) moderated the emotional eating-stress relationship. Participants: Participants were 97 college freshmen (73% female; BMI: M = 25.3…

  3. Work Stress and Alcohol Use: Developing and Testing a Biphasic Self-Medication Model

    OpenAIRE

    Frone, Michael R.

    2016-01-01

    This study developed and tested a moderated-mediation model of work stress and alcohol use, based on the biphasic (stimulant and sedative) effects of alcohol and the self-medication and stress-vulnerability models of alcohol use. The model proposes that exposure to work stressors can increase both negative affect and work fatigue, and that these two sources of strain can subsequently motivate the use of alcohol. However, the relations of negative affect and work fatigue to a...

  4. Dispositional Affect Moderates the Stress-Buffering Effect of Social Support on Risk for Developing the Common Cold.

    Science.gov (United States)

    Janicki Deverts, Denise; Cohen, Sheldon; Doyle, William J

    2017-10-01

    The aim was to examine whether trait positive and negative affect (PA, NA) moderate the stress-buffering effect of perceived social support on risk for developing a cold subsequent to being exposed to a virus that causes mild upper respiratory illness. Analyses were based on archival data from 694 healthy adults (M age  = 31.0 years, SD = 10.7 years; 49.0% female; 64.6% Caucasian). Perceived social support and perceived stress were assessed by self-report questionnaire and trait affect by aggregating responses to daily mood items administered by telephone interview across several days. Subsequently, participants were exposed to a virus that causes the common cold and monitored for 5 days for clinical illness (infection + objective signs of illness). Two 3-way interactions emerged-Support × Stress × PA and Support × Stress × NA. The nature of these effects was such that among persons with high trait PA or low trait NA, greater social support attenuated the risk of developing a cold when under high but not low perceived stress; this stress-buffering effect did not emerge among persons with low trait PA or high trait NA. Dispositional affect might be used to identify individuals who may be most responsive to social support and support-based interventions. © 2016 Wiley Periodicals, Inc.

  5. Community violence exposure and post-traumatic stress reactions among Gambian youth: the moderating role of positive school climate.

    Science.gov (United States)

    O'Donnell, Deborah A; Roberts, William C; Schwab-Stone, Mary E

    2011-01-01

    Community violence exposure among youth can lead to various negative outcomes, including post-traumatic stress symptoms. Research in the Western world indicates that a number of social support factors may moderate the relation between violence exposure and internalizing symptoms. Little research has been carried out in non-Western countries. This study aimed to fill this gap by exploring the relations among violence exposure, parental warmth, positive school climate, and post-traumatic stress reactions among youth in The Republic of The Gambia, Africa. A school-based survey of youth behaviors, feelings, attitudes, and perceptions was administered to 653 students at senior secondary schools in four Gambian communities. Students reported high levels of exposure to violence. Over half of students reported witnessing someone threatened with serious physical harm, beaten up or mugged, attacked or stabbed with a knife/piece of glass, or seriously wounded in an incident of violence. Nearly half of students reported being beaten up or mugged during the past year, and nearly a quarter reported being threatened with serious physical harm. There were no sex differences in levels of exposure. Traumatic stress symptoms were common, especially among females. Both violence witnessing and violent victimization significantly predicted post-traumatic stress symptoms, and positive school climate moderated the relationship. Among youth victimized by violence, positive school climate was most strongly correlated with lower levels of post-traumatic stress at low levels of exposure. Among youth who had witnessed violence, positive school climate was most strongly correlated with lower levels of post-traumatic stress at high levels of exposure. Community-based programs that bring together parents, schools, and youth may play an important role in combating the negative effects of some types of violence exposure among Gambian youth. Youth experiencing high levels of violent victimization

  6. Academic Stress and Health: Exploring the Moderating Role of Personality Hardiness

    Science.gov (United States)

    Hystad, Sigurd W.; Eid, Jarle; Laberg, Jon C.; Johnsen, Bjorn H.; Bartone, Paul T.

    2009-01-01

    Attending university is a pleasurable experience for many students. Yet for others it represents a highly stressful time of extensive studying and pressure to meet the requirements of academia. Academic stress is associated with a variety of negative outcomes such as physical illness and deteriorating mental health. This paper explores the…

  7. Relationship Between Intrinsic Motivation and Undergraduate Students' Depression and Stress: The Moderating Effect of Interpersonal Conflict.

    Science.gov (United States)

    Huang, Yunhui; Lv, Wei; Wu, Jiang

    2016-10-01

    This study examined the effect of intrinsic academic motivation and interpersonal conflict on the perceived depression and stress. Participants were 537 Chinese undergraduate students (191 males and 346 females; M age = 20.4 years, SD age = 1.3). They completed four scales measuring intrinsic academic motivation, interpersonal conflict, stress, and depression. Linear regressions were conducted with intrinsic academic motivation, interpersonal conflict, and their interaction as independent variables to predict depression and stress. Results showed that intrinsic academic motivation was negatively, while interpersonal conflict was positively, associated with depression and stress. Moreover, the interaction was significant: negative association of "intrinsic academic motivation and depression" and that of "intrinsic academic motivation and stress" was weaker among participants who reported higher (vs. lower) levels of interpersonal conflict. © The Author(s) 2016.

  8. Effort-reward imbalance and organisational injustice among aged nurses: a moderated mediation model.

    Science.gov (United States)

    Topa, Gabriela; Guglielmi, Dina; Depolo, Marco

    2016-09-01

    To test the effort-reward imbalance model among older nurses, expanding it to include the moderation of overcommitment and age in the stress-health complaints relationship, mediated by organisational injustice. The theoretical framework included the effort-reward imbalance, the uncertainty management and the socio-emotional selectivity models. Employing a two-wave design, the participants were 255 nurses aged 45 years and over, recruited from four large hospitals in Spain (Madrid and Basque Country). The direct effect of imbalance on health complaints was supported: it was significant when overcommitment was low but not when it was high. Organisational injustice mediated the influence of effort-reward imbalance on health complaints. The conditional effect of the mediation of organisational injustice was significant in three of the overcommitment/age conditions but it weakened, becoming non-significant, when the level of overcommitment was low and age was high. The study tested the model in nursing populations and expanded it to the settings of occupational health and safety at work. The results of this study highlight the importance of effort-reward imbalance and organisational justice for creating healthy work environments. © 2016 John Wiley & Sons Ltd.

  9. Work Stress and Depressive Symptoms in Fishermen With a Smoking Habit: A Mediator Role of Nicotine Dependence and Possible Moderator Role of Expressive Suppression and Cognitive Reappraisal.

    Science.gov (United States)

    Jiang, Hongjuan; Li, Sailan; Yang, Juan

    2018-01-01

    This study examined pathways of influence between work stress, depressive symptoms, nicotine dependence, expressive suppression, and cognitive reappraisal in fishermen with smoking habits in Qionghai, Hainan province, China (N = 1068). These fishermen responded to multiple assessments a week before leaving on a deep-sea fishing trip, including a Mental Stressor Investigation Questionnaire (MSIQ), the Center for Epidemiological Studies Depression Scale (CES-D), the Russell Reason for Smoking Questionnaire (RRSQ), and an Emotion Regulation Questionnaire (ERQ). Structural equation modeling (SEM) analyses of the collected data in Mplus 7 showed that work stress and nicotine dependence were independent predictors of depressive symptoms. The relationship between work stress and depressive symptoms was found to be partially mediated by nicotine dependence and be moderated by cognitive reappraisal. The evidence suggests it advantageous to examine the need of work stress, nicotine dependence, and cognitive reappraisal when attempting to understand depressive symptoms in fishermen with a smoking habit. These findings suggest that improving nicotine dependence through work stress management and training in cognitive reappraisal could be utilized as effective modalities for improving depressive symptoms.

  10. The Role of Coping in Moderating the Relationship between Racism-Related Stress and Self-Reported General Health among Asians and Latinas/os in the United States

    OpenAIRE

    Castro, Denise Carina

    2017-01-01

    Previous research has shown an association between racism-related stress and negative health outcomes among African Americans and the moderating effect of coping strategies on this relationship. Yet, scant attention has been paid to this relationship for two of the largest minority groups in the United States: Asians and Latinos/as. Using the 2009 California Health Interview Survey (CHIS) and a framework derived from stress process and biopsychosocial models, this study examines the relation...

  11. Co-rumination via cellphone moderates the association of perceived interpersonal stress and psychosocial well-being in emerging adults.

    Science.gov (United States)

    Murdock, Karla Klein; Gorman, Sarah; Robbins, Maia

    2015-01-01

    Adolescents' and emerging adults' social interactions increasingly revolve around cellphone use, but little research has investigated the psychological properties of cellphone interactions. The current study explored co-rumination via cellphone; that is, the use of cellphone functions to excessively communicate about problems or negative feelings. Face-to-face co-rumination and co-rumination via cellphone were examined as potential moderators of the association between perceived interpersonal stress and psychosocial well-being (i.e., positive mental health and social burnout) in a sample of 142 college students. Face-to-face co-rumination was not a moderator. However, co-rumination via cellphone was a significant moderator such that higher levels of perceived interpersonal stress were associated with lower levels of well-being only among college students who reported higher levels of co-rumination via cellphone. Co-rumination via cellphone should be further investigated to elucidate its developmental trajectory and mental health correlates. Copyright © 2014 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

  12. The moderating role of resilience on the relationship between perceived stress and binge eating symptoms among young adult women.

    Science.gov (United States)

    Thurston, Idia B; Hardin, Robin; Kamody, Rebecca C; Herbozo, Sylvia; Kaufman, Caroline

    2018-04-01

    Adolescence and young adulthood are developmental periods during the life course that are sometimes associated with heightened stress and engagement in binge eating. Binge eating has been linked to psychiatric comorbidity, poorer physical health, and lower quality of life. However, less is known about protective factors that could buffer against binge eating behaviors. The current study examined the moderating role of resilience on the relationship between perceived stress and binge eating symptoms among emerging adult female college students. Participants were 297 young adult women aged 18-25 years (M age  = 19.22, SD = 1.51; 52% self-identifying as a racial/ethnic minority) with Body Mass Index ranging from 15 to 66 (M BMI  = 25.01, SD = 6.18). Women completed this cross-sectional study while they were attending universities in the Western or Southern United States. Participants provided demographic and height/weight information, and completed the following measures: Perceived Stress Scale, Binge Eating Scale, and Brief Resilience Scale. Higher perceived stress was significantly associated with more severe binge eating symptoms (b = 0.31; p relationship between perceived stress and binge eating symptoms varied by resilience level (b = -0.16; p stress were more likely to engage in binge eating relative to women experiencing low stress; however, resilience attenuated this association. Resilience could be targeted to reduce the negative effects of perceived stress on eating behaviors in young women. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Optimism moderates psychophysiological responses to stress in older people with Type 2 diabetes.

    Science.gov (United States)

    Puig-Perez, S; Hackett, R A; Salvador, A; Steptoe, A

    2017-04-01

    Optimism is thought to be beneficial for health, and these effects may be mediated through modifications in psychophysiological stress reactivity. Type 2 diabetes (T2D) is associated with reduced cardiovascular responses to stress and heightened cortisol over the day. This study assessed the relationships between optimism, stress responsivity, and daily cortisol output in people with T2D. A total of 140 participants with T2D were exposed to laboratory stress. Heart rate (HR), systolic (SBP), diastolic blood pressure (DBP), and cortisol were measured throughout the session. Cortisol output over the day was also assessed. Optimism and self-reported health were measured using the revised Life Orientation Test and the Short Form Health Survey. Optimism was associated with heightened SBP and DBP stress reactivity (ps Optimism was not related to HR, cortisol stress responses, or the cortisol awakening response (ps > .180). Low optimism was related to poorer self-reported physical and mental health (ps Optimism could have a protective role in modulating stress-related autonomic and neuroendocrine dysregulation in people with T2D. © 2016 The Authors. Psychophysiology published by Wiley Periodicals, Inc. on behalf of Society for Psychophysiological Research.

  14. A novel locus in the oxidative stress-related gene ALOX12 moderates the association between PTSD and thickness of the prefrontal cortex.

    Science.gov (United States)

    Miller, Mark W; Wolf, Erika J; Sadeh, Naomi; Logue, Mark; Spielberg, Jeffrey M; Hayes, Jasmeet P; Sperbeck, Emily; Schichman, Steven A; Stone, Angie; Carter, Weleetka C; Humphries, Donald E; Milberg, William; McGlinchey, Regina

    2015-12-01

    Oxidative stress has been implicated in many common age-related diseases and is hypothesized to play a role in posttraumatic stress disorder (PTSD)-related neurodegeneration (Miller and Sadeh, 2014). This study examined the influence of the oxidative stress-related genes ALOX 12 and ALOX 15 on the association between PTSD and cortical thickness. Factor analyses were used to identify and compare alternative models of the structure of cortical thickness in a sample of 218 veterans. The best-fitting model was then used for a genetic association analysis in White non-Hispanic participants (n=146) that examined relationships between 33 single nucleotide polymorphisms (SNPs) spanning the two genes, 8 cortical thickness factors, and each SNP×PTSD interaction. Results identified a novel ALOX12 locus (indicated by two SNPs in perfect linkage disequilibrium: rs1042357 and rs10852889) that moderated the association between PTSD and reduced thickness of the right prefrontal cortex. A whole-cortex vertex-wise analysis showed this effect to be localized to clusters spanning the rostral middle frontal gyrus, superior frontal gyrus, rostral anterior cingulate cortex, and medial orbitofrontal cortex. These findings illustrate a novel factor-analytic approach to neuroimaging-genetic analyses and provide new evidence for the possible involvement of oxidative stress in PTSD-related neurodegeneration. Published by Elsevier Ltd.

  15. The Relationship between Teacher Stress and Burnout in Hong Kong: Positive Humour and Gender as Moderators

    Science.gov (United States)

    Ho, Sammy K.

    2017-01-01

    In this study, we report on the relationship between positive humour and burnout among 379 secondary school teachers in Hong Kong, and explore whether the relationship varies according to gender. The moderating effects of both affiliative and self-enhancing humour on each burnout component were then examined. High affiliative and self-enhancing…

  16. Impaired transcriptional activity of Nrf2 in age-related myocardial oxidative stress is reversible by moderate exercise training.

    Directory of Open Access Journals (Sweden)

    Sellamuthu S Gounder

    Full Text Available Aging promotes accumulation of reactive oxygen/nitrogen species (ROS/RNS in cardiomyocytes, which leads to contractile dysfunction and cardiac abnormalities. These changes may contribute to increased cardiovascular disease in the elderly. Inducible antioxidant pathways are regulated by nuclear erythroid 2 p45-related factor 2 (Nrf2 through antioxidant response cis-elements (AREs and are impaired in the aging heart. Whereas acute exercise stress (AES activates Nrf2 signaling and promotes myocardial antioxidant function in young mice (~2 months, aging mouse (>23 months hearts exhibit significant oxidative stress as compared to those of the young. The purpose of this study was to investigate age-dependent regulation of Nrf2-antioxidant mechanisms and redox homeostasis in mouse hearts and the impact of exercise. Old mice were highly susceptible to oxidative stress following high endurance exercise stress (EES, but demonstrated increased adaptive redox homeostasis after moderate exercise training (MET; 10m/min, for 45 min/day for ~6 weeks. Following EES, transcription and protein levels for most of the ARE-antioxidants were increased in young mice but their induction was blunted in aging mice. In contrast, 6-weeks of chronic MET promoted nuclear levels of Nrf2 along with its target antioxidants in the aging heart to near normal levels as seen in young mice. These observations suggest that enhancing Nrf2 function and endogenous cytoprotective mechanisms by MET, may combat age-induced ROS/RNS and protect the myocardium from oxidative stress diseases.

  17. Alcohol Use Disorder History Moderates the Relationship Between Avoidance Coping and Posttraumatic Stress Symptoms

    OpenAIRE

    Hruska, Bryce; Fallon, William; Spoonster, Eileen; Sledjeski, Eve M.; Delahanty, Douglas L.

    2011-01-01

    Avoidance coping (AVC) is common in individuals with posttraumatic stress disorder (PTSD) and in individuals with alcohol use disorder (AUD). Given that PTSD and AUD commonly co-occur, AVC may represent a risk factor for the development of comorbid post-traumatic stress and alcohol use. In this study, the relationship between AVC and PTSD symptoms (PTSS) was examined in individuals with versus without AUDs. Motor vehicle accident (MVA) victims were assessed 6-weeks post accident for AUD histo...

  18. Hierarchy stability moderates the effect of status on stress and performance in humans.

    Science.gov (United States)

    Knight, Erik L; Mehta, Pranjal H

    2017-01-03

    High social status reduces stress responses in numerous species, but the stress-buffering effect of status may dissipate or even reverse during times of hierarchical instability. In an experimental test of this hypothesis, 118 participants (57.3% female) were randomly assigned to a high- or low-status position in a stable or unstable hierarchy and were then exposed to a social-evaluative stressor (a mock job interview). High status in a stable hierarchy buffered stress responses and improved interview performance, but high status in an unstable hierarchy boosted stress responses and did not lead to better performance. This general pattern of effects was observed across endocrine (cortisol and testosterone), psychological (feeling in control), and behavioral (competence, dominance, and warmth) responses to the stressor. The joint influence of status and hierarchy stability on interview performance was explained by feelings of control and testosterone reactivity. Greater feelings of control predicted enhanced interview performance, whereas increased testosterone reactivity predicted worse performance. These results provide direct causal evidence that high status confers adaptive benefits for stress reduction and performance only when the social hierarchy is stable. When the hierarchy is unstable, high status actually exacerbates stress responses.

  19. Number of recent stressful life events and incident cardiovascular disease: Moderation by lifetime depressive disorder.

    Science.gov (United States)

    Berntson, Jessica; Patel, Jay S; Stewart, Jesse C

    2017-08-01

    We investigated whether number of recent stressful life events is associated with incident cardiovascular disease (CVD) and whether this relationship is stronger in adults with a history of clinical depression. Prospective data from 28,583 U.S. adults (mean age=45years) initially free of CVD who participated in Waves 1 (2001-2002) and 2 (2004-2005) of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) were examined. Number of past-year stressful life events (Wave 1), lifetime depressive disorder (Wave 1), and incident CVD (Wave 2) were determined by structured interviews. There were 1069 cases of incident CVD. Each additional stressful life event was associated with a 15% increased odds of incident CVD [Odds Ratio (OR)=1.15, 95% Confidence Interval (CI): 1.11, 1.19]. As hypothesized, a stressful life events by lifetime depressive disorder interaction was detected (P=0.003). Stratified analyses indicated that stressful life events had a stronger association with incident CVD among adults with (OR=1.18, 95% CI: 1.10, 1.27, n=4908) versus without (OR=1.10, 95% CI: 1.07, 1.14, n=23,675) a lifetime depressive disorder. Our findings suggest that a greater number of recent stressful life events elevate the risk of new-onset CVD and that this risk is potentiated in adults with a history of clinical depression. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Social Support as Mediator and Moderator of the Relationship Between Parenting Stress and Life Satisfaction Among the Chinese Parents of Children with ASD.

    Science.gov (United States)

    Lu, Ming-Hui; Wang, Guang-Hai; Lei, Hao; Shi, Meng-Liang; Zhu, Rui; Jiang, Fan

    2018-04-01

    Although numerous studies have demonstrated that social support affects a range of life experiences, few have examined its moderating and mediating effects. In the current study, 479 Chinese parents of children with ASD (aged 3-18 years) completed the surveys assessing parenting stress, social support and life satisfaction. Results indicated that parenting stress, social support and life satisfaction were significantly related. Moreover, social support both mediated and moderated the influence of parenting stress on life satisfaction. These findings imply that parenting stress and social support are critical indicators of life satisfaction and can serve as basic intervention strategies that promote life satisfaction among Chinese parents of children with ASD.

  1. Caregiver Burden Among Caregivers of Individuals With Severe Mental Illness: Testing the Moderation and Mediation Models of Resilience.

    Science.gov (United States)

    Mulud, Zamzaliza Abdul; McCarthy, Geraldine

    2017-02-01

    The association between the socio-demographic characteristics of caregivers, such as gender and caregiver burden, is well documented; however, the process underlying this relationship is poorly understood. Based on the stress process model, we designed a cross-sectional study to examine the mediating and moderating effect of resilience on the relationship between gender and caregiver burden. Caregivers of individuals with severe mental illness (n=201) were recruited in two psychiatric outpatient clinics in Malaysia. The relationship between the gender of the caregiver and caregiver burden was mediated by resilience, thus supporting the stress process model. The findings from the present research contribute to the growing evidence of the interaction between socio-demographic variables of caregivers and resilience, and caregiver burden. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Models, Mechanisms and Moderators Dissociating Empathy and Theory of Mind.

    Science.gov (United States)

    Kanske, Philipp; Böckler, Anne; Singer, Tania

    Most instances of social interaction provide a wealth of information about the states of other people, be it sensations, feelings, thoughts, or convictions. How we represent these states has been a major question in social neuroscience, leading to the identification of two routes to understanding others: an affective route for the direct sharing of others' emotions (empathy) that involves, among others, anterior insula and middle anterior cingulate cortex and a cognitive route for representing and reasoning about others' states (Theory of Mind) that entails, among others, ventral temporoparietal junction and anterior and posterior midline regions. Additionally, research has revealed a number of situational and personal factors that shape the functioning of empathy and Theory of Mind. Concerning situational modulators, it has been shown, for instance, that ingroup membership enhances empathic responding and that Theory of Mind performance seems to be susceptible to stress. Personal modulators include psychopathological conditions, for which alterations in empathy and mentalizing have consistently been demonstrated; people on the autism spectrum, for instance, are impaired specifically in mentalizing, while spontaneous empathic responding seems selectively reduced in psychopathy. Given the multifaceted evidence for separability of the two routes, current research endeavors aiming at fostering interpersonal cooperation explore the differential malleability of affective and cognitive understanding of others.

  3. The impact of eurythmy therapy on stress coping strategies and health-related quality of life in healthy, moderately stressed adults.

    Science.gov (United States)

    Kanitz, Jenny Lena; Pretzer, Kim; Reif, Marcus; Voss, Andreas; Brand, Ralf; Warschburger, Petra; Längler, Alfred; Henze, Günter; Seifert, Georg

    2011-10-01

    'Stress' and 'health-related quality of life' (HRQoL) are two important theoretical constructs for modern therapy evaluation with clinical relevance. Eurythmy therapy (EYT) is a mind-body-therapy derived from anthroposophic medicine with promising effects on heart rate variability (HRV), HRQoL and disease scores. The purpose of this study was to investigate the impact of EYT on stress coping strategies (SCS) and HRQoL in a controlled study with moderately stressed participants. 68 healthy, moderately stressed adults (mean age: 42.2; SD: 8.2) performed 10h of EYT in a group setting over a period of six weeks. A non-randomised control group of 22 healthy adults (mean age: 43.6; SD: 13.7) received no intervention and did only complete the questionnaires at the same data points. Outcomes were measured before and after the intervention (AVEM & SF-36). A significant impact on SCS was found in seven AVEM scales (MANOVA, F (1/74)=4.59; p=.04). With regard to changes in risk pattern affiliation (AVEM), 24% of the participants receiving EYT (n=55) changed over time from a risky stress coping pattern to a healthier pattern. Concerning the HRQoL four normally distributed scales of the SF-36 ('vitality', 'social functioning', 'mental health' and 'physical functioning') showed a significant group×time interaction favouring the EYT group (MANOVA, F (1/74)=17.26; phealthy individuals and possibly in patients with chronic diseases, for example. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. Oxidative stress and antioxidant biomarker responses after a moderate-intensity soccer training session.

    Science.gov (United States)

    Mello, Rodrigo; Mello, Ricardo; Gomes, Diego; Paz, Gabriel Andrade; Nasser, Igor; Miranda, Humberto; Salerno, Verônica P

    2017-01-01

    The present study investigated the effects of a moderate-intensity soccer training session on the production of reactive oxygen species (ROS) and the antioxidant capacity in athletes along with the biomarkers creatine kinase and transaminases for lesions in muscle and liver cells. Twenty-two male soccer players participated in this study. Blood samples were collected 5 min before and after a moderate-intensity game simulation. The results showed a decrease in the concentration of reduced glutathione (GSH) from an elevation in the production of ROS that maintained the redox homeostasis. Although the session promoted an elevated energy demand, observed by an increase in lactate and glucose levels, damage to muscle and/or liver cells was only suggested by a significant elevation in the levels of alanine transaminase (ALT). Of the two biomarkers analysed, the results suggest that measurements of the ALT levels could be adopted as a method to monitor recovery in athletes.

  5. Daily family stress and HPA axis functioning during adolescence: The moderating role of sleep

    Science.gov (United States)

    Chiang, Jessica J.; Tsai, Kim M.; Park, Heejung; Bower, Julienne E.; Almeida, David M.; Dahl, Ronald E.; Irwin, Michael R.; Seeman, Teresa E.; Fuligni, Andrew J.

    2017-01-01

    The present study examined the moderating role of sleep in the association between family demands and conflict and hypothalamic-pituitary-adrenal (HPA) axis functioning in a sample of ethnically diverse adolescents (n = 316). Adolescents completed daily diary reports of family demands and conflict for 15 days, and wore actigraph watches during the first 8 nights to assess sleep. Participants also provided five saliva samples for 3 consecutive days to assess diurnal cortisol rhythms. Regression analyses indicated that sleep latency and efficiency moderated the link between family demands and the cortisol awakening response. Specifically, family demands were related to a smaller cortisol awakening response only among adolescents with longer sleep latency and lower sleep efficiency. These results suggest that certain aspects of HPA axis functioning may be sensitive to family demands primarily in the context of longer sleep latency and lower sleep efficiency. PMID:27235639

  6. Does political ideology moderate stress: the special case of soldiers conducting forced evacuation.

    Science.gov (United States)

    Shechner, Tomer; Slone, Michelle; Bialik, Gadi

    2007-04-01

    This study examined the moderating role of political ideology on psychological outcomes for Israeli soldiers participating in the forced evacuation of Jewish settlements from Gaza. Change in psychopathology and well-being was assessed for 3 concurrent mission groups differing in their political ideological contentiousness--forced evacuation, Gaza security, and Northern border security. After soldiers in each mission group were classified on the basis of relatively left- or right-wing political ideological tendencies, the authors examined differential impact of each mission on soldiers of differing political ideology. Results confirmed strong moderation effects of political ideology on psychological outcomes in these extreme contexts. Implications for research, prevention, and treatment are discussed. 2007 APA, all rights reserved

  7. Leadership styles and occupational stress among college athletic directors: the moderating effect of program goals.

    Science.gov (United States)

    Ryska, Todd A

    2002-03-01

    The interaction between an individual's abilities and the perceived demands of the workplace appears to make a unique contribution to job-related stress above and beyond that of dispositional or situational factors alone (R. S. Lazarus, 1990). In the present study, the author evaluated this contention among 245 male intercollegiate athletic directors by assessing the combined influence of leadership style and program goals on occupational stress. Regression analyses revealed the presence of both significant main effects and interaction effects of leadership style and program goals in the prediction of emotional exhaustion, daily job stress, and personal accomplishment. Findings are discussed in terms of person-environment fit theory (J. R. P. French, R. D. Caplan, & R. V. Harrison, 1982) and the notion of perceived control within the occupational setting.

  8. Moderation instead of modelling: some arguments against formal engineering methods

    NARCIS (Netherlands)

    Rauterberg, G.W.M.; Sikorski, M.; Rauterberg, G.W.M.

    1998-01-01

    The more formal the used engineering techniques are, the less non-technical facts can be captured. Several business process reengineering and software development projects fail, because the project management concentrates to much on formal methods and modelling approaches. A successful change of

  9. Adiposity moderates links from early adversity and depressive symptoms to inflammatory reactivity to acute stress during late adolescence.

    Science.gov (United States)

    Chiang, Jessica J; Bower, Julienne E; Irwin, Michael R; Taylor, Shelley E; Fuligni, Andrew J

    2017-11-01

    Both early adversity and depression are associated with heightened inflammation. However, few studies have focused on inflammatory reactivity to psychosocial stress and examined adiposity as a potential moderator. Yet, repeated heightened inflammatory reactivity over time is thought to contribute to low-grade chronic inflammation and adipose tissue is a key source of pro-inflammatory cytokines. The purpose of the present study was to examine whether early adversity and depressive symptoms were related to stress-induced inflammation and whether these associations varied by total body and abdominal adiposity as measured by body mass index (BMI) and waist circumference (WC) in a sample of late adolescents. Participants reported on their early family environment and current depressive symptoms, had their height, weight, and WC assessed for adiposity markers, and provided blood samples for IL-6 assessment before and after a standardized laboratory stress task. No main effect of early adversity on IL-6 reactivity to acute stress was observed. However, significant interactions between early adversity and BMI and WC emerged. Greater exposure to early adversity was associated with greater IL-6 responses only among adolescents with higher BMI or WC. The same pattern of findings was observed for depressive symptoms. Additionally, moderated mediation analyses indicated that among adolescents with greater adiposity, early adversity indirectly influenced IL-6 reactivity via current depressive symptoms. These findings contribute to our understanding of vulnerability factors that may amplify the associations between early adversity and depressive symptoms and inflammation during relatively early stages of life. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Perceived stress and life satisfaction: social network service use as a moderator.

    Science.gov (United States)

    Niu, Qikun; Liu, Yihao; Sheng, Zitong; He, Yue; Shao, Xiaolin

    2011-01-01

    Social Network Service (SNS) has become a buzzword in recent media coverage with the development of the second generation of Web-based communities. In China, SNS has played an increasingly important role in its users' daily lives, especially among students. With a sample of 471 college students, we tested the direct relationship between perceived stress and life satisfaction using a regression analysis. Moreover, we found SNS use could buffer the negative effect of perceived stress. This study has practical implications on Internet users' SNS use.

  11. ANSYS Modeling of Hydrostatic Stress Effects

    Science.gov (United States)

    Allen, Phillip A.

    1999-01-01

    Classical metal plasticity theory assumes that hydrostatic pressure has no effect on the yield and postyield behavior of metals. Plasticity textbooks, from the earliest to the most modem, infer that there is no hydrostatic effect on the yielding of metals, and even modem finite element programs direct the user to assume the same. The object of this study is to use the von Mises and Drucker-Prager failure theory constitutive models in the finite element program ANSYS to see how well they model conditions of varying hydrostatic pressure. Data is presented for notched round bar (NRB) and "L" shaped tensile specimens. Similar results from finite element models in ABAQUS are shown for comparison. It is shown that when dealing with geometries having a high hydrostatic stress influence, constitutive models that have a functional dependence on hydrostatic stress are more accurate in predicting material behavior than those that are independent of hydrostatic stress.

  12. Revised Reynolds Stress and Triple Product Models

    Science.gov (United States)

    Olsen, Michael E.; Lillard, Randolph P.

    2017-01-01

    Revised versions of Lag methodology Reynolds-stress and triple product models are applied to accepted test cases to assess the improvement, or lack thereof, in the prediction capability of the models. The Bachalo-Johnson bump flow is shown as an example for this abstract submission.

  13. Temperament Moderates Associations between Exposure to Stress and Children's Externalizing Problems

    Science.gov (United States)

    Schermerhorn, Alice C.; Bates, John E.; Goodnight, Jackson A.; Lansford, Jennifer E.; Dodge, Kenneth A.; Pettit, Gregory S.

    2013-01-01

    The interaction between a temperament profile (four groups determined by high vs. low resistance to control [unmanageability] and unadaptability [novelty distress]) and family stress in predicting externalizing problems at school in children followed from kindergarten through eighth grade (ages 5-13) was investigated. The sample consisted of 556…

  14. Reward dependence moderates smoking-cue- and stress-induced cigarette cravings.

    Science.gov (United States)

    Michalowski, Alexandra; Erblich, Joel

    2014-12-01

    Cigarette cravings following exposure to smoking cues in a smoker's environment are thought to play an important role in cessation failure. The possibility that dispositional factors may impact cue-induced cravings, though intriguing, has received little attention. According to Cloninger's Tridimensional Personality Theory, factors such as reward dependence (RD), harm avoidance (HA), and novelty seeking (NS) may figure prominently in risk for addiction, as well as relapse, in individuals attempting to abstain from drug and alcohol use. Particularly interesting in this regard is the possibility that smokers with higher levels of RD, who are especially sensitive to reward signals, will have heightened craving reactions to smoking cues. To that end, non-treatment-seeking nicotine dependent smokers (n=96, mean age=41.1, 47% African American, 17% Caucasian, 22% Hispanic, 19.3cigs/day, FTND=7.5) underwent a classic experimental cue-induction, during which they were exposed to imagery of: (1) smoking, (2) neutral, and (3) stress cues, and reported their cigarette cravings (0-100) before and after each exposure. Participants also completed the Tridimensional Personality Questionnaire. Not surprisingly, smoking and stress cues (but not neutral cues) elicited significant elevations in craving (p'scues (pcues (pcues. Furthermore, the similar effects of RD on stress-induced craving suggest that both cue-and stress-induced cravings may be influenced by a common underlying disposition. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Family-Level Coparenting Processes and Child Gender as Moderators of Family Stress and Toddler Adjustment

    Science.gov (United States)

    Kolak, Amy M.; Vernon-Feagans, Lynne

    2008-01-01

    The goal of this multi-method study was to examine how child gender and coparenting processes influence associations between family stress and toddlers' social adjustment. The participants, 104 dual-earner couples and their 2-year-old children, were videotaped in their home during a freeplay activity. Mothers and fathers completed questionnaires…

  16. 5-HTTLPR X Stress in Adolescent Depression: Moderation by MAOA and Gender

    Science.gov (United States)

    Priess-Groben, Heather A.; Hyde, Janet Shibley

    2013-01-01

    Depression surges in adolescence, especially among girls. Most evidence indicates that the short allele of a polymorphism in the promoter region of the serotonin transporter gene (5-HTTLPR) interacts with stress to influence the onset of depression. This effect appears to be less robust in adolescents, particularly among boys, and may be moderated…

  17. Attachment Representation and Sensitivity : The Moderating Role of Posttraumatic Stress Disorder in a Refugee Sample

    NARCIS (Netherlands)

    van Ee, Elisa; Jongmans, Marian J; van der Aa, Niels; Kleber, Rolf J

    2016-01-01

    It has been hypothesized that adult attachment representations guide caregiving behavior and influence parental sensitivity, and thus affect the child's socio-emotional development. Several studies have shown a link between posttraumatic stress disorder (PTSD) and reduced parental sensitivity, so it

  18. Role Stress and Aggression among Young Adults: The Moderating Influences of Gender and Adolescent Aggression

    Science.gov (United States)

    Liu, Ruth X.; Kaplan, Howard B.

    2004-01-01

    Using data provided by a panel of non-Hispanic white respondents, this study explored whether aggressive response to severe role stress during early adulthood depends on gender and on an adolescent history of aggression. Logistic regression analysis yielded these findings: Men who reported aggression during early adolescence were significantly…

  19. Humor Use Moderates the Relation of Stressful Life Events With Psychological Distress.

    Science.gov (United States)

    Fritz, Heidi L; Russek, Leslie N; Dillon, Melissa M

    2017-06-01

    Three studies examined humor and adjustment to stressful events. In Study 1, patients with fibromyalgia syndrome ( N = 22) reported on mental and physical adjustment, social interaction, and reappraisal of their illness. Dispositional humor was associated with reduced distress and fewer physical symptoms. Study 2 ( N = 109) examined undergraduates' reports of stressful events. Dispositional, self-enhancing, affiliative, and self-defeating humor showed direct effects on distress, which were mediated by social interaction and reappraisal. Moreover, dispositional and aggressive humor showed stress-buffering effects. Study 3 ( N = 105) examined undergraduates' adjustment to the September 11, 2001, attacks at 1 and 3 months postattack. At T1, affiliative humor showed a stress-buffering effect on distress. Social interaction mediated the relation of self-enhancing humor with reduced T1 distress, and mediated relations of aggressive and self-defeating humor with greater distress. Relations of T1 dispositional and self-defeating humor to changes in T2 distress were mediated by reappraisal.

  20. The rate of diffusion into advanced gas cooled reactor moderator bricks: an equivalent cylinder model

    International Nuclear Information System (INIS)

    Kyte, W.S.

    1980-01-01

    The graphite moderator bricks which make up the moderator of an advanced gas-cooled nuclear reactor (AGR) are of many different and complex shapes. Many physico-chemical processes that occur within these porous bricks include a diffusional step and thus to model these processes it is necessary to solve the diffusion equation (with chemical reaction) in a porous medium of complex shape. A finite element technique is applied to calculating the rate at which nitrogen diffuses into and out of the porous moderator graphite during operation of a shutdown procedure for an AGR. However, the finite element method suffers from several disadvantages that undermine its general usefulness for calculating rates of diffusion in AGR moderator cores. A model which overcomes some of these disadvantages is presented (the equivalent cylinder model) and it is shown that this gives good results for a variety of different boundary and initial conditions

  1. Maternal mind-mindedness and toddler behavior problems: The moderating role of maternal trauma and posttraumatic stress.

    Science.gov (United States)

    Easterbrooks, M Ann; Crossman, Molly K; Caruso, Alessandra; Raskin, Maryna; Miranda-Julian, Claudia

    2017-10-01

    Maternal mind-mindedness (MM) reflects a caregiver's tendency to view a child as an individual with an independent mind. Research has linked higher MM with more favorable parenting and child adaptation. The aim of this study was to examine whether MM was associated with toddlers' behavior problems and competence, and the moderating role of trauma and posttraumatic stress disorder (PTSD) in a sample (N = 212) of adolescent mothers and their toddlers. MM was coded from maternal utterances during free play; mothers completed the University of California at Los Angeles Trauma and Posttraumatic Stress Disorder Reaction Index and reported on children's behavior problems and competence using the Brief Infant-Toddler Social and Emotional Assessment. The majority of mothers (84%) experienced trauma; 45% of these mothers met criteria for partial or full PTSD. Trauma was related to greater behavior problems, and PTSD moderated MM-child functioning relations. When mothers experienced full PTSD, there was no relation between MM and behavior problems. With child competence, when compared to children of mothers with no trauma exposure, children of mothers experiencing partial PTSD symptoms were more likely to have delays in competence when mothers made more MM comments. Results are discussed in light of how MM, in the context of trauma and PTSD, may affect parenting.

  2. Fatigue Moderates the Relationship Between Perceived Stress and Suicidal Ideation: Evidence From Two High-Resolution Studies.

    Science.gov (United States)

    Kleiman, Evan M; Turner, Brianna J; Chapman, Alexander L; Nock, Matthew K

    2018-01-01

    Theoretical models of self-harm suggest that high perceived stress and high fatigue (which might affect the ability to cope with stress) may interact to predict the short-term occurrence of suicidal ideation and nonsuicidal self-injury (NSSI). We tested 3 approaches to examining this interaction, each of which provided a different understanding of the specific nature of these associations: comparing each individual's daily stress/fatigue to the entire sample's overall average (i.e., grand-mean centering), comparing each individual's daily perceived stress/fatigue to his or her overall average (i.e., group- or participant-mean centering), and comparing each individual's average perceived stress/fatigue to the sample's overall average (i.e., centering participant means on overall grand mean). In 2 studies, adolescents (n = 30; 574 daily reports, M age = 17.3 years, range = 12-19; 87.6% female) and young adults (n = 60; 698 daily reports; M age = 23.25 years, range = 18-35; 85% female) completed daily measures of perceived stress, fatigue, suicidal ideation, and NSSI. In both samples, the interaction between high daily perceived stress and high daily fatigue predicted greater odds of daily suicidal ideation (but not NSSI). Only the model comparing each individual's daily stress/fatigue to the entire sample's overall average was consistently significant across the two studies. Participants were most likely to experience suicidal ideation on days when both perceived stress and fatigue were elevated relative to the average level experienced across people and time points. Studies should build upon these findings with more in-depth examination of the temporal nature of stability and change in these factors as they relate to sustained suicidal ideation.

  3. Perceived causal relations between anxiety, posttraumatic stress and depression: extension to moderation, mediation, and network analysis.

    Science.gov (United States)

    Frewen, Paul A; Schmittmann, Verena D; Bringmann, Laura F; Borsboom, Denny

    2013-01-01

    Previous research demonstrates that posttraumatic memory reexperiencing, depression, anxiety, and guilt-shame are frequently co-occurring problems that may be causally related. The present study utilized Perceived Causal Relations (PCR) scaling in order to assess participants' own attributions concerning whether and to what degree these co-occurring problems may be causally interrelated. 288 young adults rated the frequency and respective PCR scores associating their symptoms of posttraumatic reexperiencing, depression, anxiety, and guilt-shame. PCR scores were found to moderate associations between the frequency of posttraumatic memory reexperiencing, depression, anxiety, and guilt-shame. Network analyses showed that the number of feedback loops between PCR scores was positively associated with symptom frequencies. Results tentatively support the interpretation of PCR scores as moderators of the association between different psychological problems, and lend support to the hypothesis that increased symptom frequencies are observed in the presence of an increased number of causal feedback loops between symptoms. Additionally, a perceived causal role for the reexperiencing of traumatic memories in exacerbating emotional disturbance was identified.

  4. Perceived causal relations between anxiety, posttraumatic stress and depression: extension to moderation, mediation, and network analysis

    Directory of Open Access Journals (Sweden)

    Paul A. Frewen

    2013-08-01

    Full Text Available Background: Previous research demonstrates that posttraumatic memory reexperiencing, depression, anxiety, and guilt-shame are frequently co-occurring problems that may be causally related. Objectives: The present study utilized Perceived Causal Relations (PCR scaling in order to assess participants’ own attributions concerning whether and to what degree these co-occurring problems may be causally interrelated. Methods: 288 young adults rated the frequency and respective PCR scores associating their symptoms of posttraumatic reexperiencing, depression, anxiety, and guilt-shame. Results: PCR scores were found to moderate associations between the frequency of posttraumatic memory reexperiencing, depression, anxiety, and guilt-shame. Network analyses showed that the number of feedback loops between PCR scores was positively associated with symptom frequencies. Conclusion: Results tentatively support the interpretation of PCR scores as moderators of the association between different psychological problems, and lend support to the hypothesis that increased symptom frequencies are observed in the presence of an increased number of causal feedback loops between symptoms. Additionally, a perceived causal role for the reexperiencing of traumatic memories in exacerbating emotional disturbance was identified.

  5. Long-term moderate treadmill exercise promotes stress-coping strategies in male and female rats.

    Science.gov (United States)

    Lalanza, Jaume F; Sanchez-Roige, Sandra; Cigarroa, Igor; Gagliano, Humberto; Fuentes, Silvia; Armario, Antonio; Capdevila, Lluís; Escorihuela, Rosa M

    2015-11-05

    Recent evidence has revealed the impact of exercise in alleviating anxiety and mood disorders; however, the exercise protocol that exerts such benefit is far from known. The current study was aimed to assess the effects of long-term moderate exercise on behavioural coping strategies (active vs. passive) and Hypothalamic-Pituitary-Adrenal response in rats. Sprague-Dawley male and female rats were exposed to 32-weeks of treadmill exercise and then tested for two-way active avoidance learning (shuttle-box). Two groups were used as controls: a non-handled sedentary group, receiving no manipulation, and a control group exposed to a stationary treadmill. Female rats displayed shorter escape responses and higher number of avoidance responses, reaching criterion for performance earlier than male rats. In both sexes, exercise shortened escape latencies, increased the total number of avoidances and diminished the number of trials needed to reach criterion for performance. Those effects were greater during acquisition in female rats, but remained over the shuttle-box sessions in treadmill trained male rats. In females, exercise did not change ACTH and corticosterone levels after shuttle-box acquisition. Collectively, treadmill exercise improved active coping strategies in a sex-dependent manner. In a broader context, moderate exercise could serve as a therapeutic intervention for anxiety and mood disorders.

  6. Stress and nurses' horizontal mobbing: moderating effects of group identity and group support.

    Science.gov (United States)

    Topa, Gabriela; Moriano, Juan A

    2013-01-01

    Horizontal mobbing is a process of systematic and repeated aggression towards a worker by coworkers. Among others, stress has been pointed out as one of the antecedents that favors the onset of horizontal mobbing, whereas group support to the target could act as a buffer. Moreover, the social identity approach emphasizes that group identity is an antecedent of group support. This study explores the interaction of group support and group identity in the explanation of horizontal mobbing in a sample (N = 388) of registered nurses and licensed practical nurses employed at two large hospitals in Madrid and Navarre (Spain). The results show that stress is positively associated to horizontal mobbing, whereas group support and group identity were negative predictors of horizontal mobbing. Furthermore, the combination of low group identity and low group support precipitated HM among nurses. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. Age As Moderator of Emotional Stroop Task Performance in Posttraumatic Stress Disorder (PTSD)

    OpenAIRE

    Bielecki, Maksymilian; Popiel, Agnieszka; Zawadzki, Bogdan; Sedek, Grzegorz

    2017-01-01

    Emotional Stroop task (EST) has been extensively used to investigate attentional processes in posttraumatic stress disorder (PTSD). Even though aging significantly changes the dynamics of emotion-cognition interactions, very little is known about its role in shaping EST performance in PTSD patients. In the present study we tested a uniquely large sample of motor vehicle accident victims. Data of 194 participants (75.3% female; mean age = 36.64 years, SD = 12.3) were included in the analysis, ...

  8. A Review of Potential Moderating Factors in the Stress-Performance Relationship

    Science.gov (United States)

    1992-06-01

    is .85 and the scale correlated .59 with the Coopersmith Self-esteem Inventory. Although the scale is brief, it is thorough in its assessment of self...acceptance (Robinson & Shaver, 1973). The Coopersmith Self-Esteem Inventory ( Coopersmith , 1967) measures individuals’ self-evaluative attitudes...Wills, T. A. (1985). Stress, social support, and the buffering hypothesis. Psychological Bulletin, 98, 310- 357. Coopersmith , S. (1967). The

  9. Multilevel structural equation models for assessing moderation within and across levels of analysis.

    Science.gov (United States)

    Preacher, Kristopher J; Zhang, Zhen; Zyphur, Michael J

    2016-06-01

    Social scientists are increasingly interested in multilevel hypotheses, data, and statistical models as well as moderation or interactions among predictors. The result is a focus on hypotheses and tests of multilevel moderation within and across levels of analysis. Unfortunately, existing approaches to multilevel moderation have a variety of shortcomings, including conflated effects across levels of analysis and bias due to using observed cluster averages instead of latent variables (i.e., "random intercepts") to represent higher-level constructs. To overcome these problems and elucidate the nature of multilevel moderation effects, we introduce a multilevel structural equation modeling (MSEM) logic that clarifies the nature of the problems with existing practices and remedies them with latent variable interactions. This remedy uses random coefficients and/or latent moderated structural equations (LMS) for unbiased tests of multilevel moderation. We describe our approach and provide an example using the publicly available High School and Beyond data with Mplus syntax in Appendix. Our MSEM method eliminates problems of conflated multilevel effects and reduces bias in parameter estimates while offering a coherent framework for conceptualizing and testing multilevel moderation effects. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  10. Race/ethnicity moderates the relationship between chronic life stress and quality of life in type 2 diabetes.

    Science.gov (United States)

    Shallcross, Amanda J; Ojie, Mary-Jane; Chaplin, William; Levy, Natalie; Odedosu, Taiye; Ogedegbe, Gbenga; Spruill, Tanya M

    2015-04-01

    To determine whether chronic life stress is differentially associated with quality of life (QoL) for Blacks vs. Hispanics with type 2 diabetes. We assessed self-reported chronic stress and QoL in 125 patients with type 2 diabetes who self-identified as either non-Hispanic Black or Hispanic. Separate cross-sectional two-way interaction models (stress × race/ethnicity) with physical and mental health as outcomes were examined. The two-way interaction predicted mental (b=3.12, P=.04) but not physical health. Simple slopes analyses indicated that under conditions of high stress, Blacks (b=-4.4, Pstress × race/ethnicity × social support) with physical and mental health as outcomes. Results indicated the three-way interaction predicted mental (b=.62, P=.01) but not physical health. Simple slopes analyses indicated that under conditions of high stress, high levels of social support improved mental health for Hispanics (b=1.2, Pstress. Social support buffers effects of stress on mental health in Hispanics but not Blacks, which suggests differences in the use and/or quality of social support between Hispanics and Blacks. Longitudinal investigations that examine race/ethnicity, stress, social support, and QoL should help clarify the processes that underlie these observed relations. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  11. ADAPTATION MODEL FOR REDUCING THE MANAGERIAL STRESS

    Directory of Open Access Journals (Sweden)

    VIOLETA GLIGOROVSKI

    2017-12-01

    Full Text Available Changes are an inseparable component of the company's life cycle and they can contribute to its essential growth in the future. The purpose of this paper is to explain managerial stress caused by implementation of changes and creating an adaptation model to decrease managerial stress. How much the manager will successfully lead the project for implementation of a change and how much they will manage to amortize stress among employees, mostly depends on their expertise, knowledge and skills to accurately and comprehensively inform and integrate the employees in the overall process. The adaptation model is actually a new approach and recommendation for managers for dealing with stress when the changes are implemented. Methodology. For this purpose, the data presented, in fact, were collected through a questionnaire that was submitted to 61 respondents/ managers. The data were measured using the Likert scale from 1 to 7. Namely, with the help of the Likert scale, quantification of stress was made in relation to the various variables that were identified as the most important for the researched issues. An adaption model (new approach for amortizing changes was created using the DIA Diagram application, to show the relations between manager and the relevant amortization approaches.

  12. Modeling the impact of normative beliefs in the context of online buying: Direct and moderating effects

    OpenAIRE

    Iconaru Claudia

    2012-01-01

    Normative beliefs tend to play a significant role in the context of online buying, having both direct and moderating effects. The results of the structural equation modeling indicate a direct effect of normative beliefs on the intention to buy online. Also, the magnitude of the relationship between online trust and perceived risk depends on the level of normative beliefs, showing that the effect of online trust on perceived risk varies as a function of the level of the moderator variable. Thi...

  13. Relationships between the pituitary-adrenal hormones, insulin, and glucose in middle-aged men: moderating influence of psychosocial stress.

    Science.gov (United States)

    Keltikangas-Järvinen, L; Ravaja, N; Räikkönen, K; Hautanen, A; Adlercreutz, H

    1998-12-01

    We examined whether the relationships between the pituitary-adrenal hormones (corticotropin [ACTH) and cortisol), insulin, and glucose differ as a function of psychosocial stress defined in terms of vital exhaustion (VE) and depressive behavior (DB). The participants were 69 normotensive and 21 unmedicated borderline hypertensive (BH) middle-aged men whose work is stressful. Hormonal and metabolic variables were measured during an oral glucose tolerance test (OGTT), and the cortisol response to dexamethasone (DXM) suppression and intravenous ACTH stimulation was also measured. We found that the basal ACTH level during the OGTT was positively associated with the cortisol response to ACTH at 60 minutes, the fasting insulin level, and the insulin to glucose ratio among exhausted and high DB men, while the reverse was true for nonexhausted and low DB men. Also, a high cortisol response to ACTH, a low cortisol level during the OGTT, and a high ratio of these cortisol determinations (cortisol ratio) were associated with high fasting insulin and glucose levels, the summed insulin values, and the insulin to glucose ratio only among nonexhausted and low DB men; among exhausted and high DB men, these associations were less pronounced, absent, or in the opposite direction. The findings suggest that VE and DB have a moderating influence on the relationships among the hormonal and metabolic parameters studied. Psychosocial stress may affect the pituitary-adrenocortical system in complex ways, contributing thereby to insulin resistance, hyperinsulinemia, and coronary heart disease (CHD) risk.

  14. Physiological stress reactivity and physical and relational aggression: the moderating roles of victimization, type of stressor, and child gender.

    Science.gov (United States)

    Murray-Close, Dianna; Crick, Nicki R; Tseng, Wan-Ling; Lafko, Nicole; Burrows, Casey; Pitula, Clio; Ralston, Peter

    2014-08-01

    The purpose of the present investigation was to examine the association between physiological reactivity to peer stressors and physical and relational aggression. Potential moderation by actual experiences of peer maltreatment (i.e., physical and relational victimization) and gender were also explored. One hundred ninety-six children (M = 10.11 years, SD = 0.64) participated in a laboratory stress protocol during which their systolic blood pressure, diastolic blood pressure, and skin conductance reactivity to recounting a relational stressor (e.g., threats to relationships) and an instrumental stressor (e.g., threats to physical well-being, dominance, or property) were assessed. Teachers provided reports of aggression and victimization. In both boys and girls, physical aggression was associated with blunted physiological reactivity to relational stress and heightened physiological reactivity to instrumental stress, particularly among youth higher in victimization. In girls, relational aggression was most robustly associated with blunted physiological reactivity to relational stressors, particularly among girls exhibiting higher levels of relational victimization. In boys, relational aggression was associated with heightened physiological reactivity to both types of stressors at higher levels of peer victimization and blunted physiological reactivity to both types of stressors at lower levels of victimization. Results underscore the shared and distinct emotional processes underlying physical and relational aggression in boys and girls.

  15. Moderating effects of coping on work stress and job performance for nurses in tertiary hospitals: a cross-sectional survey in China

    OpenAIRE

    Li, Li; Ai, Hua; Gao, Lei; Zhou, Hao; Liu, Xinyan; Zhang, Zhong; Sun, Tao; Fan, Lihua

    2017-01-01

    Background Work stress is a major problem for nurses and it can negatively influence job performance. Therefore, it is critical to explore variables that can reduce or buffer the negative effects of work stress. This study explores the moderating effects of coping strategies on the relationship between work stress and job performance for nurses in China. Methods A cross-sectional survey of 852 nurses from four tertiary hospitals in Heilongjiang Province, China, was conducted in 2013. Descript...

  16. Performance assessment of turbulence models for the prediction of moderator thermal flow inside CANDU calandria

    International Nuclear Information System (INIS)

    Lee, Gong Hee; Bang, Young Seok; Woo, Sweng Woong

    2012-01-01

    The moderator thermal flow in the CANDU calandria is generally complex and highly turbulent because of the interaction of the buoyancy force with the inlet jet inertia. In this study, the prediction performance of turbulence models for the accurate analysis of the moderator thermal flow are assessed by comparing the results calculated with various types of turbulence models in the commercial flow solver FLUENT with experimental data for the test vessel at Sheridan Park Engineering Laboratory (SPEL). Through this comparative study of turbulence models, it is concluded that turbulence models that include the source term to consider the effects of buoyancy on the turbulent flow should be used for the reliable prediction of the moderator thermal flow inside the CANDU calandria

  17. Regularized Estimation of Structural Instability in Factor Models: The US Macroeconomy and the Great Moderation

    DEFF Research Database (Denmark)

    Callot, Laurent; Kristensen, Johannes Tang

    This paper shows that the parsimoniously time-varying methodology of Callot and Kristensen (2015) can be applied to factor models.We apply this method to study macroeconomic instability in the US from 1959:1 to 2006:4 with a particular focus on the Great Moderation. Models with parsimoniously time...... that the parameters of both models exhibit a higher degree of instability in the period from 1970:1 to 1984:4 relative to the following 15 years. In our setting the Great Moderation appears as the gradual ending of a period of high structural instability that took place in the 1970s and early 1980s....

  18. A comprehensive model of stress - The roles of experienced stress and neuroticism in explaining the stress-distress relationship

    NARCIS (Netherlands)

    De Jong, GM; van Sonderen, E; Emmelkamp, PMG

    1999-01-01

    Background: In this study, a complex theoretical model regarding the stress-distress relationship was evaluated. The various components in the model included experienced stress (daily hassles), psychological distress, neuroticism, problem-focused coping, avoidant coping, satisfaction with received

  19. Cortisol responses to psychosocial stress predict depression trajectories: social-evaluative threat and prior depressive episodes as moderators.

    Science.gov (United States)

    Morris, Matthew C; Rao, Uma; Garber, Judy

    2012-12-20

    Alterations of hypothalamic-pituitary-adrenal (HPA) function are well-established in adults with current depression. HPA alterations may persist into remission and confer increased risk for recurrence. A modified version of the Trier Social Stress Test (TSST) was administered at baseline to 32 young adults with remitted major depressive disorder and 36 never-depressed controls. Participants were randomly assigned to either a 'high-stress' condition involving social evaluation or a 'low-stress' control condition. Cortisol concentrations were measured in saliva samples throughout the TSST. Participants were assessed again after 6 months for the occurrence of stressful life events and depressive symptoms/disorders during the follow-up period. Participants who exhibited enhanced cortisol reactivity in the low-stress condition showed increases in depressive symptoms over follow-up, after controlling for stressful life events during the follow-up period. Anticipatory stress cortisol and cortisol reactivity each interacted with history of depressive episodes to predict depression trajectories. The single TSST administration limits conclusions about whether alterations of cortisol reactivity represent trait-like vulnerability factors or consequences ("scars') of past depression. These results extend previous findings on stress sensitivity in depression and suggest that altered HPA function during remission could reflect an endophenotype for vulnerability to depression recurrence. Findings support interactive models of risk for depression recurrence implicating HPA function, depression history, and sensitivity to minor stressors. Results may have implications for interventions that match treatment approaches to profiles of HPA function. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Moderating Factors of Video-Modeling with Other as Model: A Meta-Analysis of Single-Case Studies

    Science.gov (United States)

    Mason, Rose A.; Ganz, Jennifer B.; Parker, Richard I.; Burke, Mack D.; Camargo, Siglia P.

    2012-01-01

    Video modeling with other as model (VMO) is a more practical method for implementing video-based modeling techniques, such as video self-modeling, which requires significantly more editing. Despite this, identification of contextual factors such as participant characteristics and targeted outcomes that moderate the effectiveness of VMO has not…

  1. The moderating effect of trait emotional intelligence on mood deterioration following laboratory-induced stress

    Directory of Open Access Journals (Sweden)

    Moïra Mikolajczak

    2009-01-01

    Full Text Available Una grand cantidad de investigación ha demostrado una asociación entre el rasgo de inteligencia emocional (IE y salud mental. Varias vías pueden contribuir a esta relación. Primero, es posible que la asociación entre el rasgo de IE y la salud mental sea un mero artefacto de los métodos y medidas utilizadas (vía sesgos de respuesta. Segundo, el rasgo de IE puede reducir la susceptibilidad a trastornos mentales mediante la sucesión de mecanismos biológicos (vía neuroendocrina. Tercero, el rasgo de IE puede reducir la susceptibilidad a trastornos minimizando las alteraciones del estado de ánimo en diferentes circunstancias (vía de afecto. Este estudio experimental tiene como objetivo documentar la tercera vía. Presenta tres estudios experimentales sobre el rol moderador del rasgo de inteligencia emocional (IE rasgo en el deterioro del estado de ánimo después del estrés inducido en el laboratorio. La validez incremental del rasgo de IE para predecir los cambios del estado de ánimo más la deseabilidad social, alexitimia, resiliencia y el modelo de personalidad de los cinco factores también fue estudiada. Regresiones múltiples sobre las tres muestras y también sobre la muestra combinada (N = 196, demostraron que a la IE rasgo moderó significativamente el impacto del estresor experimental en el subsecuente deterioro del estado de ánimo, b el efecto se mantuvo después de haber controlado la deseabilidad social y c la IE rasgo tuvo una validez incremental para predecir el deterioro del estado de ánimo sobre otros predictores.

  2. The BDNF Val66Met polymorphism moderates the relationship between Posttraumatic Stress Disorder and fear extinction learning.

    Science.gov (United States)

    Felmingham, Kim L; Zuj, Daniel V; Hsu, Ken Chia Ming; Nicholson, Emma; Palmer, Matthew A; Stuart, Kimberley; Vickers, James C; Malhi, Gin S; Bryant, Richard A

    2018-05-01

    The low expression Met allele of the BDNF Val66Met polymorphism is associated with impaired fear extinction in healthy controls, and poorer response to exposure therapy in patients with Posttraumatic Stress Disorder (PTSD). Given that fear extinction underlies exposure therapy, this raises the question of the impact of BDNFVal66Met polymorphism on fear extinction in PTSD, yet this question has not yet been examined. One hundred and six participants (22 PTSD, 46 trauma-exposed controls (TC) and 38 non-trauma exposed controls (NTC)) completed a fear conditioning and extinction task and saliva samples were taken for DNA extraction and genotyped for the BDNF Val66Met polymorphism. Moderation analyses using PROCESS examined whether BDNF genotype (Val-Val vs Met carriers) moderated the relationship between PTSD symptom severity (and diagnostic status) and skin conductance response (SCR) amplitude during fear extinction. The PTSD group displayed significantly slower fear extinction learning compared to TC and NTC in the early extinction phase. The BDNF Val66Met polymorphism moderated the relationship between PTSD and fear extinction learning, such that poorer fear extinction learning was associated with greater PTSD symptom severity (and PTSD diagnostic status) in individuals with the low-expression Met allele, but no relationship was demonstrated in individuals with the Val-Val allele. This study reveals that impaired fear extinction learning is particularly evident in individuals with PTSD who carry the low-expression BDNF Met allele and importantly not in those with the Val-Val allele. This provides novel evidence of a link between BDNF and impaired fear extinction learning in PTSD, which may contribute to poorer response to exposure therapy. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Enhanced Thermostability of Arabidopsis Rubisco Activase Improves Photosynthesis and Growth Rates under Moderate Heat Stress[OA

    Science.gov (United States)

    Kurek, Itzhak; Chang, Thom Kai; Bertain, Sean M.; Madrigal, Alfredo; Liu, Lu; Lassner, Michael W.; Zhu, Genhai

    2007-01-01

    Plant photosynthesis declines when the temperature exceeds its optimum range. Recent evidence indicates that the reduction in photosynthesis is linked to ribulose-1,5-bis-phosphate carboxylase/oxygenase (Rubisco) deactivation due to the inhibition of Rubisco activase (RCA) under moderately elevated temperatures. To test the hypothesis that thermostable RCA can improve photosynthesis under elevated temperatures, we used gene shuffling technology to generate several Arabidopsis thaliana RCA1 (short isoform) variants exhibiting improved thermostability. Wild-type RCA1 and selected thermostable RCA1 variants were introduced into an Arabidopsis RCA deletion (Δrca) line. In a long-term growth test at either constant 26°C or daily 4-h 30°C exposure, the transgenic lines with the thermostable RCA1 variants exhibited higher photosynthetic rates, improved development patterns, higher biomass, and increased seed yields compared with the lines expressing wild-type RCA1 and a slight improvement compared with untransformed Arabidopsis plants. These results provide clear evidence that RCA is a major limiting factor in plant photosynthesis under moderately elevated temperatures and a potential target for genetic manipulation to improve crop plants productivity under heat stress conditions. PMID:17933901

  4. Race moderates the association of Catechol-O-methyltransferase genotype and posttraumatic stress disorder in preschool children.

    Science.gov (United States)

    Humphreys, Kathryn L; Scheeringa, Michael S; Drury, Stacy S

    2014-10-01

    The present study sought to replicate previous findings of an association between the Catechol-O-methyltransferase (COMT) val158met polymorphism with posttraumatic stress disorder (PTSD) and symptomatology in a novel age group, preschool children. COMT genotype was determined in a sample of 171 3-6-year-old trauma-exposed children. PTSD was assessed with a semistructured interview. Accounting for sex, trauma type, and age, genotype was examined in relation to categorical and continuous measures of PTSD both controlling for race and within the two largest racial categories (African American [AA] and European American [EA]). Race significantly moderated the association between genotype and PTSD. Specifically, the genotype associated with increased PTSD symptoms in one racial group had the opposite association in the other racial group. For AA children the met/met genotype was associated with more PTSD symptoms. However, for EA children, val allele carriers had more PTSD symptoms. Whereas every AA child with the met/met genotype met criteria for PTSD, none of the EA children with the met/met genotype did. This genetic association with COMT genotype, in both races but in opposite directions, was most associated with increased arousal symptoms. These findings replicate previous findings in participants of African descent, highlight the moderating effect of race on the association between COMT genotype and PTSD, and provide direct evidence that consideration of population stratification within gene-by-environment studies is valuable to prevent false negative findings.

  5. Adjusting membrane lipids under salt stress: the case of the moderate halophilic organism Halobacillus halophilus.

    Science.gov (United States)

    Lopalco, Patrizia; Angelini, Roberto; Lobasso, Simona; Köcher, Saskia; Thompson, Melanie; Müller, Volker; Corcelli, Angela

    2013-04-01

    The lipid composition of Halobacillus halophilus was investigated by combined thin-layer chromatography and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analyses of the total lipid extract. Main polar lipids were found to be sulfoquinovosyldiacylglycerol and phosphatidylglycerol, while cardiolipin was a minor lipid together with phosphatidic acid, alanyl-phosphatidylglycerol and two not yet fully identified lipid components. In addition the analyses of residual lipids, associated with denatured proteins after the lipid extraction, revealed the presence of significant amounts of cardiolipin, indicating that it is a not readily extractable phospholipid. Post decay source mass spectrometry analyses allowed the determination of acyl chains of main lipid components. On increasing the culture medium salinity, an increase in the shorter chains and the presence of chain unsaturations were observed. These changes in the lipid core structures might compensate for the increase in packing and rigidity of phospholipid and sulfoglycolipid polar heads in high-salt medium, therefore contributing to the homeostasis of membrane fluidity and permeability in salt stress conditions. © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd.

  6. PHIT for Duty, a Mobile Application for Stress Reduction, Sleep Improvement, and Alcohol Moderation.

    Science.gov (United States)

    Kizakevich, Paul N; Eckhoff, Randall; Brown, Janice; Tueller, Stephen J; Weimer, Belinda; Bell, Stacey; Weeks, Adam; Hourani, Laurel L; Spira, James L; King, Laurel A

    2018-03-01

    Post-traumatic stress and other problems often occur after combat, deployment, and other military operations. Because techniques such as mindfulness meditation show efficacy in improving mental health, our team developed a mobile application (app) for individuals in the armed forces with subclinical psychological problems as secondary prevention of more significant disease. Based on the Personal Health Intervention Toolkit (PHIT), a mobile app framework for personalized health intervention studies, PHIT for Duty integrates mindfulness-based relaxation, behavioral education in sleep quality and alcohol use, and psychometric and psychophysiological data capture. We evaluated PHIT for Duty in usability and health assessment studies to establish app quality for use in health research. Participants (N = 31) rated usability on a 1 (very hard) to 5 (very easy) scale and also completed the System Usability Scale (SUS) questionnaire (N = 9). Results were (mean ± SD) overall (4.5 ± 0.6), self-report instruments (4.5 ± 0.7), pulse sensor (3.7 ± 1.2), sleep monitor (4.4 ± 0.7), sleep monitor comfort (3.7 ± 1.1), and wrist actigraphy comfort (2.7 ± 0.9). The average SUS score was 85 ± 12, indicating a rank of 95%. A comparison of PHIT-based assessments to traditional paper forms demonstrated a high overall correlation (r = 0.87). These evaluations of usability, health assessment accuracy, physiological sensing, system acceptability, and overall functionality have shown positive results and affirmation for using the PHIT framework and PHIT for Duty application in mobile health research.

  7. Moderate Traumatic Brain Injury: Clinical Characteristics and a Prognostic Model of 12-Month Outcome.

    Science.gov (United States)

    Einarsen, Cathrine Elisabeth; van der Naalt, Joukje; Jacobs, Bram; Follestad, Turid; Moen, Kent Gøran; Vik, Anne; Håberg, Asta Kristine; Skandsen, Toril

    2018-03-31

    Patients with moderate traumatic brain injury (TBI) often are studied together with patients with severe TBI, even though the expected outcome of the former is better. Therefore, we aimed to describe patient characteristics and 12-month outcomes, and to develop a prognostic model based on admission data, specifically for patients with moderate TBI. Patients with Glasgow Coma Scale scores of 9-13 and age ≥16 years were prospectively enrolled in 2 level I trauma centers in Europe. Glasgow Outcome Scale Extended (GOSE) score was assessed at 12 months. A prognostic model predicting moderate disability or worse (GOSE score ≤6), as opposed to a good recovery, was fitted by penalized regression. Model performance was evaluated by area under the curve of the receiver operating characteristics curves. Of the 395 enrolled patients, 81% had intracranial lesions on head computed tomography, and 71% were admitted to an intensive care unit. At 12 months, 44% were moderately disabled or worse (GOSE score ≤6), whereas 8% were severely disabled and 6% died (GOSE score ≤4). Older age, lower Glasgow Coma Scale score, no day-of-injury alcohol intoxication, presence of a subdural hematoma, occurrence of hypoxia and/or hypotension, and preinjury disability were significant predictors of GOSE score ≤6 (area under the curve = 0.80). Patients with moderate TBI exhibit characteristics of significant brain injury. Although few patients died or experienced severe disability, 44% did not experience good recovery, indicating that follow-up is needed. The model is a first step in development of prognostic models for moderate TBI that are valid across centers. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

  8. Maternal history of child abuse moderates the association between daily stress and diurnal cortisol in pregnancy: a pilot study.

    Science.gov (United States)

    Bublitz, Margaret H; Stroud, Laura R

    2013-11-01

    Previous research on the association between maternal daily stress and cortisol in pregnancy has yielded inconsistent findings. However, past studies have not considered whether stressful experiences in childhood impact maternal cortisol regulation in pregnancy. In this pilot study, we aimed to examine whether the association between maternal daily stress and cortisol differed according to maternal history of child abuse. Forty-one women provided salivary cortisol samples at wake-up, 30 min after wake-up, and bedtime for 3 days at three times over second and third trimesters of pregnancy. On each day of cortisol collection women reported their daily stress. Women reported child abuse experiences prior to age 18 years by completing 15 items from the Adverse Childhood Experiences Scale. Twenty-one percent (N = 9) of women reported a history of child sexual abuse (CSA), 44% (N = 18) reported a history of non-sexual child abuse and 34% (N = 14) reported no history of child abuse. Hierarchical Linear Modeling (HLM) analyses revealed that stress in the day prior was associated with increases in morning cortisol in women with CSA histories compared to women with non-sexual abuse histories or no history of child abuse. Increases in evening cortisol were associated with increases in daily stress in women with CSA histories compared to women with non-sexual abuse histories or no history of child abuse. Results reveal a dynamic association between daily stress and cortisol in pregnancy and suggest that patterns differ according to maternal child abuse history.

  9. The Applicability of Cognitive Mediational and Moderational Models to Explain Children's Depression Inventory Factor Scores in Urban Youth

    Science.gov (United States)

    Reinemann, Dawn H. S.; Teeter Ellison, Phyllis A.

    2004-01-01

    This investigation examined whether cognition serves as a direct factor, mediates, or moderates the relationship between stressful life events and Children's Depression Inventory (CDI; Kovacs, 1992) factor scores in urban, ethnic minority youth. Ninety-eight middle school students completed measures of stressful life events, cognition (cognitive…

  10. Directionality between Tolerance of Deviance and Deviant Behavior Is Age-Moderated in Chronically Stressed Youth

    Science.gov (United States)

    Ridenour, Ty A.; Caldwell, Linda L.; Coatsworth, J. Douglas; Gold, Melanie A.

    2011-01-01

    Problem behavior theory posits that tolerance of deviance is an antecedent to antisocial behavior and substance use. In contrast, cognitive dissonance theory implies that acceptability of a behavior may increase after experiencing the behavior. Using structural equation modeling, this investigation tested whether changes in tolerance of deviance…

  11. Determination of NABE in urine of high-yield dairy cows in early lactation in conditions of moderate heat stress

    Directory of Open Access Journals (Sweden)

    Fratrić Natalija

    2010-01-01

    Full Text Available The work presents the results of investigations of the effect of moderate heat stress on the acidobasal status in high-yield dairy cows in early lactation. Improving performance in high-yield dairy cows increases their inclination toward metabolic disorders. The most likely to be affected is the acid-base balance, in particular when cows are exposed to heat stress. Investigations so far have shown that the taking of urine samples and their analysis is the best and fastest way to diagnose disorders in the acid-base balance. Investigations were carried out on 7 clinically healthy cows of the Holstein- Friesian breed in the phase of early lactation, 30 to 40 days (on days 30, 33 and 40 following calving during the summer period, during the month of July, when there were significant variations in daily and nightly temperatures. The cows were in the second and fourth lactation, the annual milk yield was 8000 L milk per cow. The average daily milk production in the early phase of lactation ranged from 35 to 40 L. The cows were fed mixed rations (TMR twice daily. Lucerne hay in limited quantities was given to the cows prior to the mixed feed ration. The ration for this animal category was optimized on the grounds of the daily milk production. The balance of cations and anions in the feed ration stood at 95 mEq/kg DM. The results clearly demonstrate the cows' response to moderate heat stress through the defense parameters in urine (urine pH, NABE (net-acid-base-excretion, acids, bases, ammonium ion (NH4. The determination of the kidney NABE yields more correct data than the urine pH on acidotic conditions. The results of examinations of the urine pH do not show any digressions from physiological values and are approximately the same in all cows during the investigated periods. Normal NABE values are from 100-200 mmol/L. Burdening with acid products results in a NABE range from 0-100mmol/L, and metabolic acidosis results in NAB<0 mmol/L. NABE in the cows

  12. Validation of a CFD analysis model for the calculation of CANDU6 moderator temperature distribution

    International Nuclear Information System (INIS)

    Yoon, Churl; Rhee, Bo Wook; Min, Byung Joo

    2001-01-01

    A validation of a 3D CFD model for predicting local subcooling of moderator in the vicinity of calandria tubes in a CANDU reactor is performed. The small scale moderator experiments performed at Sheridan Park Experimental Laboratory (SPEL) in Ontario, Canada is used for the validation. Also a comparison is made between previous DFD analyses based on 2DMOTH and PHOENICS, and the current model analysis for the same SPEL experiment. For the current model, a set of grid structures for the same geometry as the experimental test section is generated and the momentum, heat and continuity equations are solved by CFX-4.3, a CFD code developed by AEA technology. The matrix of calandria tubes is simplified by the porous media approach. The standard κ-ε turbulence model associated with logarithmic wall treatment and SIMPLEC algorithm on the body fitted grid are used and buoyancy effects are accounted for by the Boussinesq approximation. For the test conditions simulated in this study, the flow pattern identified is a buoyancy-dominated flow, which is generated by the interaction between the dominant buoyancy force by heating and inertial momentum forces by the inlet jets. As a result, the current CFD moderator analysis model predicts the moderator temperature reasonably, and the maximum error against the experimental data is kept at less than 2.0 .deg. C over the whole domain. The simulated velocity field matches with the visualization of SPEL experiments quite well

  13. Directionality Between Tolerance of Deviance and Deviant Behavior is Age-Moderated in Chronically Stressed Youth

    OpenAIRE

    Ridenour, TY A.; Caldwell, Linda L.; Coatsworth, J. Douglas; Gold, Melanie A.

    2011-01-01

    Problem behavior theory posits that tolerance of deviance is an antecedent to antisocial behavior and substance use. In contrast, cognitive dissonance theory implies that acceptability of a behavior may increase after experiencing the behavior. Using structural equation modeling, this investigation tested whether changes in tolerance of deviance precede changes in conduct disorder criteria or substance use or vice versa, or if they change concomitantly. Two-year longitudinal data from 246 8- ...

  14. Moderating effects of coping on work stress and job performance for nurses in tertiary hospitals: a cross-sectional survey in China.

    Science.gov (United States)

    Li, Li; Ai, Hua; Gao, Lei; Zhou, Hao; Liu, Xinyan; Zhang, Zhong; Sun, Tao; Fan, Lihua

    2017-06-12

    Work stress is a major problem for nurses and it can negatively influence job performance. Therefore, it is critical to explore variables that can reduce or buffer the negative effects of work stress. This study explores the moderating effects of coping strategies on the relationship between work stress and job performance for nurses in China. A cross-sectional survey of 852 nurses from four tertiary hospitals in Heilongjiang Province, China, was conducted in 2013. Descriptive statistics were reported for socioeconomic status and demographic characteristics, level of work stress, coping strategies, and job performance. Regression analysis was conducted to test the interaction between work stress and coping strategies on job performance. Three subscales of work stress were negatively related to job performance. Positive coping strategies moderated Patient Care and job performance while negative coping strategies moderated Workload and Time and performance, and between Working Environment and Resources and performance. Positive coping strategies reduce or buffer the negative effects of work stress on job performance and negative coping strategies increased the negative effects.

  15. Validation of a CFD Analysis Model for Predicting CANDU-6 Moderator Temperature Against SPEL Experiments

    International Nuclear Information System (INIS)

    Churl Yoon; Bo Wook Rhee; Byung-Joo Min

    2002-01-01

    A validation of a 3D CFD model for predicting local subcooling of the moderator in the vicinity of calandria tubes in a CANDU-6 reactor is performed. The small scale moderator experiments performed at Sheridan Park Experimental Laboratory (SPEL) in Ontario, Canada[1] is used for the validation. Also a comparison is made between previous CFD analyses based on 2DMOTH and PHOENICS, and the current analysis for the same SPEL experiment. For the current model, a set of grid structures for the same geometry as the experimental test section is generated and the momentum, heat and continuity equations are solved by CFX-4.3, a CFD code developed by AEA technology. The matrix of calandria tubes is simplified by the porous media approach. The standard k-ε turbulence model associated with logarithmic wall treatment and SIMPLEC algorithm on the body fitted grid are used. Buoyancy effects are accounted for by the Boussinesq approximation. For the test conditions simulated in this study, the flow pattern identified is the buoyancy-dominated flow, which is generated by the interaction between the dominant buoyancy force by heating and inertial momentum forces by the inlet jets. As a result, the current CFD moderator analysis model predicts the moderator temperature reasonably, and the maximum error against the experimental data is kept at less than 2.0 deg. C over the whole domain. The simulated velocity field matches with the visualization of SPEL experiments quite well. (authors)

  16. Principal Empowering Leadership and Teacher Innovative Behavior: A Moderated Mediation Model

    Science.gov (United States)

    Gkorezis, Panagiotis

    2016-01-01

    Purpose: The purpose of this paper is to contribute to extant literature by linking principal empowering leadership to teachers' innovative work behavior. By doing so, the author attempts to provide a more nuanced understanding of this relationship by examining a moderated mediation model which encompasses exploration as a mediator and role…

  17. A meta-analysis of the technology acceptance model : investigating subjective norm and moderation effects

    NARCIS (Netherlands)

    Schepers, J.J.L.; Wetzels, M.G.M.

    2007-01-01

    We conducted a quantitative meta-analysis of previous research on the technology acceptance model (TAM) in an attempt to make well-grounded statements on the role of subjective norm. Furthermore, we compared TAM results by taking into account moderating effects of one individual-related factor (type

  18. Association between a parent's brand passion and a child's brand passion: a moderated moderated-mediation model.

    Science.gov (United States)

    Gilal, Faheem Gul; Zhang, Jian; Gilal, Naeem Gul; Gilal, Rukhsana Gul

    2018-01-01

    Both marketing scholars and brand managers have noted the importance of brand passion. They have increasingly emphasized how brand passion influences consumers' psychological states and behaviors. In contrast, an almost negligible effort has been made to study whether the individual's brand passion can be transferred to others. Using consumer socialization theory and emotional contagion theory as a lens, this study explores whether airline brand passion can be transferred from a parent to a child. To this end, a convenience sample of (N = 202) parent-child dyads was utilized to test the moderated moderated-mediation hypotheses. The results provide evidence that parents' airline passion can be translated into the child's airline passion via emotional contagion for daughters who live with their parents but not those who live independently of their parents. Similarly, parents' airline passion can be transferred to sons regardless of their geographical distance. The implications, limitations, and agendas for future research are discussed in depth.

  19. Effects of Chronic Interpersonal Stress Exposure on Depressive Symptoms are Moderated by Genetic Variation at IL6 and IL1β in Youth

    Science.gov (United States)

    Tartter, Margaret; Hammen, Constance; Bower, Julienne E.; Brennan, Patricia A.; Cole, Steven

    2015-01-01

    Aims Close to one third of patients with major depression show increases in pro-inflammatory cytokines, which are in turn associated with risk for inflammatory disease. Genetic variants that enhance immune reactivity may thus enhance inflammatory and depressive reactions to stress. The aim of the present study was to investigate a trio of functional SNPs in the promoter regions of IL6 (-174G>C, rs1800795), IL1β (-511C>T, rs16944), and TNF (-308G>A, rs1800629) as moderators of the relationship between chronic stress exposure and elevations in depressive symptoms. Methods Participants were 444 Australian youth (mean age = 20.12) whose exposure to chronic stress in the past 6 months was assessed using the semi-structured UCLA Life Stress Interview, and who completed the Beck Depression Inventory II at ages 15 and 20. Between ages 22 and 25, all participants in the selected sample provided blood samples for genotyping. Results In line with a hypothesized moderation effect, -174G allele carriers at IL6 had fewer depressive symptoms following interpersonal stress, relative to C/C homozygotes with equal interpersonal stress exposure. However, IL6 genotype did not moderate the effects of non-interpersonal stress exposure (i.e., financial, work and health-related difficulties) on depression. Also in line with hypotheses, the -511C allele in IL1β, previously associated with higher IL-1β expression, was associated with more severe depression following chronic interpersonal stress exposure, relative to T/T homozygotes. Again, the moderating effect was specific to interpersonal stressors and did not generalize to non-interpersonal stress. TNF was not a moderator of the effects of either interpersonal or non-interpersonal stress on later depression outcomes. Conclusion Findings were consistent with the hypothesis that pro-inflammatory genetic variation increases the risk of stress-induced depression. The present results provide evidence of a genetic mechanism contributing to

  20. Modeling Exposure to Heat Stress with a Simple Urban Model

    Directory of Open Access Journals (Sweden)

    Peter Hoffmann

    2018-01-01

    Full Text Available As a first step in modeling health-related urban well-being (UrbWellth, a mathematical model is constructed that dynamically simulates heat stress exposure of commuters in an idealized city. This is done by coupling the Simple Urban Radiation Model (SURM, which computes the mean radiant temperature ( T m r t , with a newly developed multi-class multi-mode traffic model. Simulation results with parameters chosen for the city of Hamburg for a hot summer day show that commuters are potentially most exposed to heat stress in the early afternoon when T m r t has its maximum. Varying the morphology with respect to street width and building height shows that a more compact city configuration reduces T m r t and therefore the exposure to heat stress. The impact resulting from changes in the city structure on traffic is simulated to determine the time spent outside during the commute. While the time in traffic jams increases for compact cities, the total commuting time decreases due to shorter distances between home and work place. Concerning adaptation measures, it is shown that increases in the albedo of the urban surfaces lead to an increase in daytime heat stress. Dramatic increases in heat stress exposure are found when both, wall and street albedo, are increased.

  1. Development of a CANDU Moderator Analysis Model; Based on Coupled Solver

    International Nuclear Information System (INIS)

    Yoon, Churl; Park, Joo Hwan

    2006-01-01

    A CFD model for predicting the CANDU-6 moderator temperature has been developed for several years in KAERI, which is based on CFX-4. This analytic model(CFX4-CAMO) has some strength in the modeling of hydraulic resistance in the core region and in the treatment of heat source term in the energy equations. But the convergence difficulties and slow computing speed reveal to be the limitations of this model, because the CFX-4 code adapts a segregated solver to solve the governing equations with strong coupled-effect. Compared to CFX-4 using segregated solver, CFX-10 adapts high efficient and robust coupled-solver. Before December 2005 when CFX-10 was distributed, the previous version of CFX-10(CFX-5. series) also adapted coupled solver but didn't have any capability to apply porous media approaches correctly. In this study, the developed moderator analysis model based on CFX- 4 (CFX4-CAMO) is transformed into a new moderator analysis model based on CFX-10. The new model is examined and the results are compared to the former

  2. Development and validation of the 3-D CFD model for CANDU-6 moderator temperature predictions

    International Nuclear Information System (INIS)

    Yoon, Churl; Rhee, Bo Wook; Min, Byung Joo

    2003-03-01

    A computational fluid dynamics model for predicting the moderator circulation inside the CANada Deuterium Uranium (CANDU) reactor vessel has been developed to estimate the local subcooling of the moderator in the vicinity of the Calandria tubes. The buoyancy effect induced by internal heating is accounted for by Boussinesq approximation. The standard κ-ε turbulence model associated with logarithmic wall treatment is applied to predict the turbulent jet flows from the inlet nozzles. The matrix of the Calandria tubes in the core region is simplified to porous media, in which an-isotropic hydraulic impedance is modeled using an empirical correlation of the frictional pressure loss. The governing equations are solved by CFX-4.4, a commercial CFD code developed by AEA technology. The CFD model has been successfully verified and validated against experimental data obtained in the Stern Laboratories Inc. (SLI) in Hamilton, Ontario

  3. Assessing moderated mediation in linear models requires fewer confounding assumptions than assessing mediation.

    Science.gov (United States)

    Loeys, Tom; Talloen, Wouter; Goubert, Liesbet; Moerkerke, Beatrijs; Vansteelandt, Stijn

    2016-11-01

    It is well known from the mediation analysis literature that the identification of direct and indirect effects relies on strong no unmeasured confounding assumptions of no unmeasured confounding. Even in randomized studies the mediator may still be correlated with unobserved prognostic variables that affect the outcome, in which case the mediator's role in the causal process may not be inferred without bias. In the behavioural and social science literature very little attention has been given so far to the causal assumptions required for moderated mediation analysis. In this paper we focus on the index for moderated mediation, which measures by how much the mediated effect is larger or smaller for varying levels of the moderator. We show that in linear models this index can be estimated without bias in the presence of unmeasured common causes of the moderator, mediator and outcome under certain conditions. Importantly, one can thus use the test for moderated mediation to support evidence for mediation under less stringent confounding conditions. We illustrate our findings with data from a randomized experiment assessing the impact of being primed with social deception upon observer responses to others' pain, and from an observational study of individuals who ended a romantic relationship assessing the effect of attachment anxiety during the relationship on mental distress 2 years after the break-up. © 2016 The British Psychological Society.

  4. Stress as a mediator between work-family conflict and psychological health among the nursing staff: Moderating role of emotional intelligence.

    Science.gov (United States)

    Sharma, Jyoti; Dhar, Rajib Lochan; Tyagi, Akansha

    2016-05-01

    The study examined the extent to which work-family conflicts cause stress among nursing staff and its subsequent impact on their psychological health. It also examined if the emotional intelligence level of the nursing staff acted as a moderator between their level of stress and psychological health. A survey was carried out on 693 nursing staff associated with 33 healthcare institutions in Uttarakhand, India. A hierarchical multiple regression analysis was carried out to understand the relationships shared by independent (work-family conflicts) and dependent (psychological health) constructs with the mediator (stress) as well as the moderator (emotional intelligence). The results revealed that stress acted as a mediator between work-family conflict of the nursing staff and their psychological health. However, their emotional intelligence level acted as a moderator between their stress level and psychological health. To conclude, the crucial roles of emotional intelligence in controlling the impact of stress on psychological health along with the practical as well as theoretical implications are also discussed. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Stress modeling of microdiaphragm pressure sensors

    Science.gov (United States)

    Tack, P. C.; Busta, H. H.

    1986-01-01

    A finite element program analysis was used to model the stress distribution of two monocrystalline silicon diaphragm pressure sensors. One configuration consists of an anisotropically backside etched diaphragm into a 250 micron thick, (100) oriented, silicon wafer. The diaphragm and total chip dimensions are given. The device is rigidly clamped on the back to a support substrate. Another configuration consists of a monocrystalline, (100), microdiaphragm which is formed on top of the wafer and whose area is reduced by a factor of 25 over the first configuration. The diaphragm is rigidly clamped to the silicon wafer. The stresses were calculated at a gauge pressure of 300 mm Hg and used to estimate the piezoresistive responses of resistor elements which were placed parallel and perpendicular near the diaphragm edges.

  6. Adverse life events, area socio-economic disadvantage, and adolescent psychopathology: The role of closeness to grandparents in moderating the effect of contextual stress.

    Science.gov (United States)

    Flouri, Eirini; Buchanan, Ann; Tan, Jo-Pei; Griggs, Julia; Attar-Schwartz, Shalhevet

    2010-09-01

    The study, using data from 801 11-16-year-olds clustered in 68 schools across England and Wales, tested whether closeness to grandparents moderates the association between contextual stress and adolescent psychopathology and prosocial behavior, measured with the strengths and difficulties questionnaire (SDQ). Contextual stress was measured at both school area level (assessed with the index of multiple deprivation) and child level (assessed, as life stress, with the number of proximal and distal adverse life events experienced). At baseline, area stress (multiple deprivation) was unrelated to psychopathology (SDQ), and although both proximal (during the last 12 months) and distal (before the last 12 months) life stress was associated with broad and specific child psychopathology, the association with proximal life stress was stronger. Closeness to the most significant grandparent moderated both the effect of proximal life stress on hyperactivity and broad psychopathology, and the effect of the interaction between distal and proximal life stress on broad and externalizing psychopathology. These findings suggest that the role of grandparents deserves further attention in future investigations of the development of resilience in youth.

  7. Aerobic exercise, ball sports, dancing, and weight lifting as moderators of the relationship between stress and depressive symptoms: an exploratory cross-sectional study with swiss university students.

    Science.gov (United States)

    Gerber, Markus; Brand, Serge; Elliot, Catherine; Holsboer-Trachsler, Edith; Pühse, Uwe

    2014-12-01

    This exploratory study was designed to compare four types of exercise activities in Swiss university students. A sample of 201 medical students (136 women, 65 men; M age = 23.2 yr., SD = 2.4) and 250 exercise and health sciences students (144 women, 106 men; M age = 22.3 yr., SD = 2.2) participated in the study. They completed the Perceived Stress Scale, the Depression Scale, and the Office in Motion Questionnaire. Interaction effects between stress and exercise activities were analysed using hierarchical regression analyses, after controlling for age, sex, and academic discipline. Frequent participation in ball sports and dancing were associated with decreased depressive symptoms among students with elevated perceived stress, whereas no such relationship existed among their peers with lower perceived stress. No stress-moderating effect was found for aerobic exercise. Weight lifting was only associated with lower depressive symptoms among students with low perceived stress. The present findings suggest that, among Swiss university students, certain exercises may have better potential to moderate the relationship between perceived stress and depressive symptoms than others. Future research could analyze whether personalized exercise programs created to satisfy participants' individual needs are more beneficial for stress management.

  8. Distress intolerance moderation of motivated attention to cannabis and negative stimuli after induced stress among cannabis users: an ERP study.

    Science.gov (United States)

    Macatee, Richard J; Okey, Sarah A; Albanese, Brian J; Schmidt, Norman B; Cougle, Jesse R

    2018-05-07

    Prevalence of cannabis use is increasing, but many regular users do not develop cannabis use disorder (CUD); thus, CUD risk identification among current users is vital for targeted intervention development. Existing data suggest that high distress intolerance (DI), an individual difference reflective of the ability to tolerate negative affect, may be linked to CUD, but no studies have tested possible neurophysiological mechanisms. Increased motivated attentional processing of cannabis and negative emotional stimuli as indexed by neurophysiology [i.e. the late positive potential (LPP)], particularly during acute stress, may contribute to CUD among high DI users. Frequent cannabis users with high (n = 61) and low DI (n = 44) viewed cannabis, negative, and matched neutral images during electroencephalography (EEG) recording before and after a laboratory stressor. Cannabis cue-elicited modulation of the 1000- to 3000-milliseconds LPP was larger in high DI users at post-stressor only, although the effect was only robust in the 1000- to 2000-milliseconds window. Further, modulation magnitude in the high DI group covaried with stress-relief craving and some CUD indices in the 400- to 1000-milliseconds and 1000- to 3000-milliseconds windows, respectively. No significant effects of DI on negative stimuli-elicited LPP modulation were found, although inverse associations with some CUD indices were observed. Finally, exploratory analyses revealed some evidence for DI moderation of the relation between subjective stressor reactivity and negative stimuli-elicited LPP modulation such that greater stressor reactivity was associated with blunted versus enhanced modulation in the high and low DI groups, respectively. Negative and cannabis stimuli-elicited LPP modulation appear to index distinct, CUD-relevant neural processes in high DI cannabis users. © 2018 Society for the Study of Addiction.

  9. Childhood Emotional Abuse Moderates Associations Among Corticomotor White Matter Structure and Stress Neuromodulators in Women With and Without Depression

    Directory of Open Access Journals (Sweden)

    Carlton P. Frost

    2018-04-01

    Full Text Available Adverse caregiving during development can produce long-lasting changes to neural, endocrine, and behavioral responses to stress, and is strongly related to elevated risk of adult psychopathology. While prior experience of adversity is associated with altered sympathetic nervous system (SNS and hypothalamic-pituitary-adrenal (HPA axis activity, the underlying neural pathways are not completely understood. In a double-blind crossover study, we used diffusion tensor imaging (DTI to examine whether variation in white matter structure predicts differences in HPA-SNS interactions as a function of early adversity. Participants included 74 women who exhibited a wide range of depression severity and/or childhood emotional abuse (EA. Participants attended two experimental sessions during which they were administered 20 mg cortisol (CORT or placebo and after 90 min, viewed emotionally laden pictures while undergoing MRI scanning. Immediately after emotional picture-viewing, we collected salivary alpha-amylase (sAA to index SNS activation. We tested whether EA moderated the relation between fractional anisotropy (FA, a measure of white matter fiber structure, and sAA. In the placebo condition, for participants with minimal history of EA, higher FA in corticomotor projections was negatively correlated with sAA, whereas in participants with severe EA, the correlation was trending in the opposite direction. Following CORT administration, FA and sAA were not related, suggesting that SNS tone during acute cortisol elevation may depend on neural pathways other than corticomotor projections. The results suggest that at baseline—though not during cortisol elevation—increased FA in these tracts is associated with lower levels of SNS activity in women with minimal EA, but not in women with severe EA. These findings provide evidence that corticomotor projections may be a key component of altered neural circuitry in adults with history of maltreatment, and may be

  10. Influence of Child Behavioral Problems and Parenting Stress on Parent-Child Conflict among Low-Income Families: The Moderating Role of Maternal Nativity

    Science.gov (United States)

    Garcia, Aileen S.; Ren, Lixin; Esteraich, Jan M.; Raikes, Helen H.

    2017-01-01

    This study was designed to examine whether parenting stress and child behavioral problems are significant predictors of parent-child conflict in the context of low-income families and how these relations are moderated by maternal nativity. The authors conducted multiple regression analyses to examine relations between teachers' report of…

  11. Genetic moderation of the association between adolescent romantic involvement and depression: Contributions of serotonin transporter gene polymorphism, chronic stress, and family discord.

    Science.gov (United States)

    Starr, Lisa R; Hammen, Constance

    2016-05-01

    Studies support a link between adolescent romantic involvement and depression. Adolescent romantic relationships may increase depression risk by introducing chronic stress, and genetic vulnerability to stress reactivity/emotion dysregulation may moderate these associations. We tested genetic moderation of longitudinal associations between adolescent romantic involvement and later depressive symptoms by a polymorphism in the serotonin transporter linked polymorphic region gene (5-HTTLPR) and examined contributory roles of chronic stress and family discord. Three hundred eighty-one youth participated at ages 15 and 20. The results indicated that 5-HTTLPR moderated the association between age 15 romantic involvement and age 20 depressive symptoms, with strongest effects for short homozygotes. Conditional process analysis revealed that chronic stress functioned as a moderated mediator of this association, fully accounting for the romantic involvement-depression link among short/short genotypes. Also, romantic involvement predicted later depressive symptoms most strongly among short-allele carriers with high family discord. The results have important implications for understanding the romantic involvement-depression link and the behavioral and emotional correlates of the 5-HTTLPR genotype.

  12. Coping Strategies as Moderators of the Relation between Individual Race-Related Stress and Mental Health Symptoms for African American Women

    Science.gov (United States)

    Greer, Tawanda M.

    2011-01-01

    The purpose of this investigation was to examine coping strategies as moderators of the relationship between individual race-related stress and mental health symptoms among a sample of 128 African American women. Coping strategies refer to efforts used to resolve problems and those used to manage, endure, or alleviate distress. Culture-specific…

  13. Social Support as Mediator and Moderator of the Relationship between Parenting Stress and Life Satisfaction among the Chinese Parents of Children with ASD

    Science.gov (United States)

    Lu, Ming-Hui; Wang, Guang-Hai; Lei, Hao; Shi, Meng-Liang; Zhu, Rui; Jiang, Fan

    2018-01-01

    Although numerous studies have demonstrated that social support affects a range of life experiences, few have examined its moderating and mediating effects. In the current study, 479 Chinese parents of children with ASD (aged 3-18 years) completed the surveys assessing parenting stress, social support and life satisfaction. Results indicated that…

  14. Moderate forest disturbance as a stringent test for gap and big-leaf models

    Science.gov (United States)

    Bond-Lamberty, B.; Fisk, J. P.; Holm, J. A.; Bailey, V.; Bohrer, G.; Gough, C. M.

    2015-01-01

    Disturbance-induced tree mortality is a key factor regulating the carbon balance of a forest, but tree mortality and its subsequent effects are poorly represented processes in terrestrial ecosystem models. It is thus unclear whether models can robustly simulate moderate (non-catastrophic) disturbances, which tend to increase biological and structural complexity and are increasingly common in aging US forests. We tested whether three forest ecosystem models - Biome-BGC (BioGeochemical Cycles), a classic big-leaf model, and the ZELIG and ED (Ecosystem Demography) gap-oriented models - could reproduce the resilience to moderate disturbance observed in an experimentally manipulated forest (the Forest Accelerated Succession Experiment in northern Michigan, USA, in which 38% of canopy dominants were stem girdled and compared to control plots). Each model was parameterized, spun up, and disturbed following similar protocols and run for 5 years post-disturbance. The models replicated observed declines in aboveground biomass well. Biome-BGC captured the timing and rebound of observed leaf area index (LAI), while ZELIG and ED correctly estimated the magnitude of LAI decline. None of the models fully captured the observed post-disturbance C fluxes, in particular gross primary production or net primary production (NPP). Biome-BGC NPP was correctly resilient but for the wrong reasons, and could not match the absolute observational values. ZELIG and ED, in contrast, exhibited large, unobserved drops in NPP and net ecosystem production. The biological mechanisms proposed to explain the observed rapid resilience of the C cycle are typically not incorporated by these or other models. It is thus an open question whether most ecosystem models will simulate correctly the gradual and less extensive tree mortality characteristic of moderate disturbances.

  15. The influence of perceived stress on work-family conflict and mental health: the moderating effect of person-environment fit.

    Science.gov (United States)

    Chu, Li-Chuan

    2014-07-01

    This study examines whether higher perceived stress among female hospital workers can result in more serious work-family conflict (WFC) and poorer mental health, and also identifies the role that person-environment (P-E) fit plays in moderating these relationships. Female hospital workers with higher perceived stress tend to report greater WFC and worse mental health than others with less perceived stress. A better fit between a person and her environment may lead to lower perceived stress. As a result, she may experience less WFC and better mental health. This study adopts a longitudinal design with 273 participants, all of whom are employed by hospitals in Taiwan. All hypotheses are tested using hierarchical regression analyses. The results show that perceived stress is an effective predictor of WFC and mental health status, whereas the P-E fit can moderate these relationships. Hospitals should pay more attention to the negative effects of perceived high stress on the WFC levels and mental health of their female employees. The P-E fit can buffer effectively the impact of perceived stress on both WFC and mental health. If hospitals can adopt appropriate human resource management practices as well as monitor and manage the P-E fit continuously, they can better help their employees to fit into the overall hospital environment. © 2012 John Wiley & Sons Ltd.

  16. Diabetes-Specific and General Life Stress and Glycemic Outcomes in Emerging Adults With Type 1 Diabetes: Is Race/Ethnicity a Moderator?

    Science.gov (United States)

    Butler, Ashley M; Weller, Bridget E; Yi-Frazier, Joyce P; Fegan-Bohm, Kelly; Anderson, Barbara; Pihoker, Catherine; Hilliard, Marisa E

    2017-10-01

    This study examines whether race/ethnicity moderates relationships of (a) diabetes stress and general life stressors with (b) diabetes outcomes of glycemic control and diabetic ketoacidosis (DKA) among emerging adults (aged 18-25 years) with type 1 diabetes (T1D). Using a T1D Exchange Registry sample of non-Hispanic White, African American, and Hispanic emerging adults (N = 3,440), multiple group analyses were used to determine whether race/ethnicity moderates the relationships between stress and diabetes outcomes. The relationships between the two stress types and glycemic control did not differ between African American and non-Hispanic Whites. However, as compared with non-Hispanic Whites, the association between higher diabetes-specific stress and poorer glycemic control was significantly stronger for Hispanics, and Hispanics had poorer glycemic control when they experienced a relatively fewer number of general life stressors than non-Hispanic Whites. The relationships between the type of stress (diabetes-specific and general stress) and DKA did not differ across racial/ethnic groups. Future research should evaluate possible mechanisms that contribute to the different relationships of stress with glycemic control among Hispanics compared with non-Hispanic Whites. © The Author 2017. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

  17. Immigration Stress and Alcohol Use Severity Among Recently Immigrated Hispanic Adults: Examining Moderating Effects of Gender, Immigration Status, and Social Support.

    Science.gov (United States)

    Cano, Miguel Ángel; Sánchez, Mariana; Trepka, Mary Jo; Dillon, Frank R; Sheehan, Diana M; Rojas, Patria; Kanamori, Mariano J; Huang, Hui; Auf, Rehab; De La Rosa, Mario

    2017-03-01

    Identifying and understanding determinants of alcohol use behavior among Hispanic immigrants is an increasingly significant public health concern. Although prior research has examined associations of cultural stressors with alcohol use among Hispanics, few studies have tested these associations among recent adult immigrants. As such, this study aimed to examine (a) the association of immigration stress on alcohol use severity among recently immigrated Hispanic adults (≤ 1 year in the United States) and (b) the moderating effects of gender, immigration status, and social support. A hierarchical multiple regression and moderation analyses were conducted on a sample of 527 participants in South Florida. Results indicated that, after controlling for demographic variables, preimmigration drinking behavior, and dimensions of social support, the association of higher immigration stress with higher alcohol use severity was statistically significant. Moderation analyses indicated that immigration stress had a statistically significant association with alcohol use severity among men, but not women. Also, dimensions of social support consistently reduced the deleterious effect of immigration stress on alcohol use severity. This study adds to the scarce literature on cultural stressors and alcohol use among recent Hispanic immigrants. Findings suggest that it may be important to design gender-specific interventions and that increasing levels of social support may offset the effects of immigration stress on alcohol use. © 2016 Wiley Periodicals, Inc.

  18. Nonpointlike-parton model with asymptotic scaling and with scaling violationat moderate Q2 values

    International Nuclear Information System (INIS)

    Chen, C.K.

    1981-01-01

    A nonpointlike-parton model is formulated on the basis of the assumption of energy-independent total cross sections of partons and the current-algebra sum rules. No specific strong-interaction Lagrangian density is introduced in this approach. This model predicts asymptotic scaling for the inelastic structure functions of nucleons on the one hand and scaling violation at moderate Q 2 values on the other hand. The predicted scaling-violation patterns at moderate Q 2 values are consistent with the observed scaling-violation patterns. A numerical fit of F 2 functions is performed in order to demonstrate that the predicted scaling-violation patterns of this model at moderate Q 2 values fit the data, and to see how the predicted asymptotic scaling behavior sets in at various x values. Explicit analytic forms of F 2 functions are obtained from this numerical fit, and are compared in detail with the analytic forms of F 2 functions obtained from the numerical fit of the quantum-chromodynamics (QCD) parton model. This comparison shows that this nonpointlike-parton model fits the data better than the QCD parton model, especially at large and small x values. Nachtman moments are computed from the F 2 functions of this model and are shown to agree with data well. It is also shown that the two-dimensional plot of the logarithm of a nonsinglet moment versus the logarithm of another such moment is not a good way to distinguish this nonpointlike-parton model from the QCD parton model

  19. Human amygdala engagement moderated by early life stress exposure is a biobehavioral target for predicting recovery on antidepressants.

    Science.gov (United States)

    Goldstein-Piekarski, Andrea N; Korgaonkar, Mayuresh S; Green, Erin; Suppes, Trisha; Schatzberg, Alan F; Hastie, Trevor; Nemeroff, Charles B; Williams, Leanne M

    2016-10-18

    Amygdala circuitry and early life stress (ELS) are both strongly and independently implicated in the neurobiology of depression. Importantly, animal models have revealed that the contribution of ELS to the development and maintenance of depression is likely a consequence of structural and physiological changes in amygdala circuitry in response to stress hormones. Despite these mechanistic foundations, amygdala engagement and ELS have not been investigated as biobehavioral targets for predicting functional remission in translational human studies of depression. Addressing this question, we integrated human neuroimaging and measurement of ELS within a controlled trial of antidepressant outcomes. Here we demonstrate that the interaction between amygdala activation engaged by emotional stimuli and ELS predicts functional remission on antidepressants with a greater than 80% cross-validated accuracy. Our model suggests that in depressed people with high ELS, the likelihood of remission is highest with greater amygdala reactivity to socially rewarding stimuli, whereas for those with low-ELS exposure, remission is associated with lower amygdala reactivity to both rewarding and threat-related stimuli. This full model predicted functional remission over and above the contribution of demographics, symptom severity, ELS, and amygdala reactivity alone. These findings identify a human target for elucidating the mechanisms of antidepressant functional remission and offer a target for developing novel therapeutics. The results also offer a proof-of-concept for using neuroimaging as a target for guiding neuroscience-informed intervention decisions at the level of the individual person.

  20. Cognitive Reserve and Social Capital Accrued in Early and Midlife Moderate the Relation of Psychological Stress to Cognitive Performance in Old Age.

    Science.gov (United States)

    Ihle, Andreas; Oris, Michel; Sauter, Julia; Rimmele, Ulrike; Kliegel, Matthias

    2018-06-05

    The present study set out to investigate the relation of psychological stress to cognitive performance and its interplay with key life course markers of cognitive reserve and social capital in a large sample of older adults. We assessed cognitive performance (verbal abilities and processing speed) and psychological stress in 2,812 older adults. The Participants reported information on education, occupation, leisure activities, family, and close friends. Greater psychological stress was significantly related to lower performance in verbal abilities and processing speed. Moderation analyses suggested that the relations of psychological stress to cognitive performance were reduced in individuals with higher education, a higher cognitive level of the first profession practiced after education, a larger number of midlife leisure activities, a larger number of significant family members, and a larger number of close friends. Cognitive reserve and social capital accrued in early and midlife may reduce the detrimental influences of psychological stress on cognitive functioning in old age. © 2018 S. Karger AG, Basel.

  1. New proposal of moderator temperature coefficient estimation method using gray-box model in NPP, (1)

    International Nuclear Information System (INIS)

    Mori, Michitsugu; Kagami, Yuichi; Kanemoto, Shigeru; Enomoto, Mitsuhiro; Tamaoki, Tetsuo; Kawamura, Shinichiro

    2004-01-01

    The purpose of the present paper is to establish a new void reactivity coefficient (VRC) estimation method based on gray box modeling concept. The gray box model consists of a point kinetics model as the first principle model and a fitting model of moderator temperature kinetics. Applying Kalman filter and maximum likehood estimation algorithms to the gray box model, MTC can be estimated. The verification test is done by Monte Carlo simulation, and, it is shown that the present method gives the best estimation results comparing with the conventional methods from the viewpoints of non-biased and smallest scattering estimation performance. Furthermore, the method is verified via real plant data analysis. The reason of good performance of the present method is explained by proper definition of likelihood function based on explicit expression of observation and system noise in the gray box model. (author)

  2. Robust Methods for Moderation Analysis with a Two-Level Regression Model.

    Science.gov (United States)

    Yang, Miao; Yuan, Ke-Hai

    2016-01-01

    Moderation analysis has many applications in social sciences. Most widely used estimation methods for moderation analysis assume that errors are normally distributed and homoscedastic. When these assumptions are not met, the results from a classical moderation analysis can be misleading. For more reliable moderation analysis, this article proposes two robust methods with a two-level regression model when the predictors do not contain measurement error. One method is based on maximum likelihood with Student's t distribution and the other is based on M-estimators with Huber-type weights. An algorithm for obtaining the robust estimators is developed. Consistent estimates of standard errors of the robust estimators are provided. The robust approaches are compared against normal-distribution-based maximum likelihood (NML) with respect to power and accuracy of parameter estimates through a simulation study. Results show that the robust approaches outperform NML under various distributional conditions. Application of the robust methods is illustrated through a real data example. An R program is developed and documented to facilitate the application of the robust methods.

  3. Internal Stress in a Model Elasto-Plastic Fluid

    OpenAIRE

    Ooshida, Takeshi; Sekimoto, Ken

    2004-01-01

    Plastic materials can carry memory of past mechanical treatment in the form of internal stress. We introduce a natural definition of the vorticity of internal stress in a simple two-dimensional model of elasto-plastic fluids, which generates the internal stress. We demonstrate how the internal stress is induced under external loading, and how the presence of the internal stress modifies the plastic behavior.

  4. Adult attachment, perceived social support, cultural orientation, and depressive symptoms: A moderated mediation model.

    Science.gov (United States)

    Zhu, Wenzhen; Wang, Chiachih Dc; Chong, Chu Chian

    2016-11-01

    In the current study, we tested a moderated mediation model in which cultural orientation moderated the mediation model of adult attachment-perceived social support-depressive symptoms, using 2 comparable cross-cultural samples of college students recruited from China and the U.S. (n = 363 for each group). Results indicated that perceived social support mediated the effect of attachment anxiety on depressive symptoms as well as the link between attachment avoidance and depression in both samples. Moderated mediation analyses using PROCESS revealed that interdependent self-construal significantly buffered the indirect effect of attachment avoidance (via perceived social support) on depressive symptoms. The findings indicated significant differences in the mediation models between the U.S. and China groups and interdependent self-construal accounted for the between-country differences. Limitations, implications of the findings, and future research directions are discussed from the perspectives of cross-cultural variation of adult attachment functioning. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  5. Resting sympathetic arousal moderates the association between parasympathetic reactivity and working memory performance in adults reporting high levels of life stress.

    Science.gov (United States)

    Giuliano, Ryan J; Gatzke-Kopp, Lisa M; Roos, Leslie E; Skowron, Elizabeth A

    2017-08-01

    The neurovisceral integration model stipulates that autonomic function plays a critical role in the regulation of higher-order cognitive processes, yet most work to date has examined parasympathetic function in isolation from sympathetic function. Furthermore, the majority of work has been conducted on normative samples, which typically demonstrate parasympathetic withdrawal to increase arousal needed to complete cognitive tasks. Little is known about how autonomic regulation supports cognitive function in populations exposed to high levels of stress, which is critical given that chronic stress exposure alters autonomic function. To address this, we sought to characterize how parasympathetic (high-frequency heart rate variability, HF-HRV) and sympathetic (preejection period, PEP) measures of cardiac function contribute to individual differences in working memory (WM) capacity in a sample of high-risk women. HF-HRV and PEP were measured at rest and during a visual change detection measure of WM. Multilevel modeling was used to examine within-person fluctuations in WM performance throughout the task concurrently with HF-HRV and PEP, as well as between-person differences as a function of resting HF-HRV and PEP levels. Results indicate that resting PEP moderated the association between HF-HRV reactivity and WM capacity. Increases in WM capacity across the task were associated with increases in parasympathetic activity, but only among individuals with longer resting PEP (lower sympathetic arousal). Follow-up analyses showed that shorter resting PEP was associated with greater cumulative risk exposure. These results support the autonomic space framework, in that the relationship between behavior and parasympathetic function appears dependent on resting sympathetic activation. © 2017 Society for Psychophysiological Research.

  6. The Moderating Role of Positive and Negative Affect on the Relationship between Perceived Social Support and Stress in College Students

    Science.gov (United States)

    Çivitci, Asim

    2015-01-01

    During college years, which are known as a stressful time, students may often face stress personally, socially, academically, economically, and so forth in various areas of life. One of the important sources that students use to cope with stress is social support. Students can cope with stress easier via the support they receive from their friends…

  7. Sense of coherence does not moderate the relationship between the perceived impact of stress on health and self-rated health in adults with congenital heart disease.

    Science.gov (United States)

    Apers, Silke; Sevenants, Lien; Budts, Werner; Luyckx, Koen; Moons, Philip

    2016-12-01

    Adults with congenital heart disease seem to be more distressed than their healthy counterparts, which might render them even more susceptible to developing detrimental health outcomes. Previous research has confirmed the relationship between the perceived impact of stress on health and self-rated health. However, it remains unknown whether sense of coherence, a person's capacity to cope with stressors, moderates this relationship. This cross-sectional study aims to explore: the relationship between demographic and clinical characteristics, sense of coherence, and the perceived impact of stress on health; the relationship between the perceived impact of stress on health and self-rated health; and the moderating effect of sense of coherence in a sample of adults with congenital heart disease. Patients were recruited from the database of congenital and structural cardiology of a university hospital. The analytic sample included 255 patients (median age 35 years; 50% men). Data were obtained using self-report questionnaires and through medical record view. Univariate analyses and multiple regression analysis were conducted. The perceived impact of stress on health was negatively associated with sense of coherence (Pstress on health and self-rated health were negatively associated (Prelationship. Our findings support the need for further research on the perceived impact of stress on health. Such insights can be valuable for developing interventions aimed at reducing the negative health consequences of stress in patients with congenital heart disease. © The European Society of Cardiology 2015.

  8. The Migration, Mental Stress, and Tobacco use of Internal Migrants in China: The Moderating Effect of the Social Context of the Host Society.

    Science.gov (United States)

    Xie, Shenghua

    2017-11-10

    Previous studies on the relationship between mental stress and the tobacco use of internal migrants have not fully considered the social context of the host society. This study aims to examine how mental stress influences cigarette smoking in internal migrants in China by considering the social context of the host society. We used the RUMiC data that were collected in 15 cities distributed throughout 9 provinces of China. A total of 8,446 and 5,426 migrant workers were interviewed in 2008 and 2009, respectively. We selected individuals based on the criteria of age, salary, and hukou status. A total of 8,880 observations are valid for this study. This research used the logistic regression method to test the association between mental stress and the tobacco use of internal migrants. The results show that mental stress is not necessarily associated with the tobacco use of internal migrants. However, the effects of mental stress on tobacco use are moderated by the social context of the host society. This article calls for more attention to be paid to the moderate effect of social context in the host society on the association between mental stress and cigarette smoking of internal migrants. Moreover, this article underscores the importance of factors related to local societies in making and enacting tobacco control policies for migrants in developing countries.

  9. Hypocaloric diet and regular moderate aerobic exercise is an effective strategy to reduce anthropometric parameters and oxidative stress in obese patients.

    Science.gov (United States)

    Gutierrez-Lopez, Liliana; Garcia-Sanchez, Jose Ruben; Rincon-Viquez, Maria de Jesus; Lara-Padilla, Eleazar; Sierra-Vargas, Martha P; Olivares-Corichi, Ivonne M

    2012-01-01

    Studies show that diet and exercise are important in the treatment of obesity. The aim of this study was to determine whether additional regular moderate aerobic exercise during a treatment with hypocaloric diet has a beneficial effect on oxidative stress and molecular damage in the obese patient. Oxidative stress of 16 normal-weight (NW) and 32 obese 1 (O1) subjects (BMI 30-34.9 kg/m(2)) were established by biomarkers of oxidative stress in plasma. Recombinant human insulin was incubated with blood from NW or O1 subjects, and the molecular damage to the hormone was analyzed. Two groups of treatment, hypocaloric diet (HD) and hypocaloric diet plus regular moderate aerobic exercise (HDMAE), were formed, and their effects in obese subjects were analyzed. The data showed the presence of oxidative stress in O1 subjects. Molecular damage and polymerization of insulin was observed more frequently in the blood from O1 subjects. The treatment of O1 subjects with HD decreased the anthropometric parameters as well as oxidative stress and molecular damage, which was more effectively prevented by the treatment with HDMAE. HD and HDMAE treatments decreased anthropometric parameters, oxidative stress, and molecular damage in O1 subjects. Copyright © 2012 S. Karger GmbH, Freiburg.

  10. The Impact of Escitalopram on Vagally Mediated Cardiovascular Function to Stress and the Moderating Effects of Vigorous Physical Activity: A Randomised Controlled Treatment Study in Healthy Participants

    Directory of Open Access Journals (Sweden)

    Camilla S Hanson

    2013-09-01

    Full Text Available Recent concerns over the impact of antidepressant medications, including the selective serotonin reuptake inhibitors (SSRIs, on cardiovascular function highlight the importance of research on the moderating effects of specific lifestyle factors such as physical activity. Studies in affective neuroscience have demonstrated robust acute effects of SSRIs, yet the impact of SSRIs on cardiovascular stress responses and the moderating effects of physical activity remain to be determined. This was the goal of the present study, which involved a double-blind, randomised, placebo-controlled, cross-over trial of a single-dose of escitalopram (20mg in 44 healthy females; outcomes were heart rate and its variability. Participants engaging in at least 30 minutes of vigorous physical activity at least 3 times per week (regular exercisers showed a more resilient cardiovascular stress response than irregular vigorous exercisers, a finding associated with a moderate effect size (Cohen’s d=0.48. Escitalopram attenuated the cardiovascular stress response in irregular exercisers only (heart rate decreased: Cohen’s d=0.80; heart rate variability increased: Cohen’s d=0.33. Heart rate during stress under escitalopram in the irregular exercisers was similar to that during stress under placebo in regular exercisers.. These findings highlight that the effects of regular vigorous exercise during stress are comparable to the effects of an acute dose of escitalopram, highlighting the beneficial effects of this particular antidepressant in irregular exercisers. Given that antidepressant drugs alone do not seem to protect patients from cardiovascular disease, longitudinal studies are needed to evaluate the impact of exercise on cardiovascular stress responses in patients receiving long-term antidepressant treatment.

  11. TV, Social Media, and College Students' Binge Drinking Intentions: Moderated Mediation Models.

    Science.gov (United States)

    Yang, Bo; Zhao, Xinyan

    2018-01-01

    Many studies to date have examined how media influence health-related behavior through social norms. However, most studies focused on traditional media. In the era of traditional and social media integration, our study advances health and mass communication scholarship by examining the influence of both traditional and social media mediated through social norms. Also, we examined a boundary condition for the norms-mediated media influence process. Namely, in the context of college binge drinking, we predict that exposure to TV and social media prodrinking messages can influence college students' binge drinking intentions through perceived peer descriptive and injunctive norms. We also predict that group identification will moderate this indirect effect. Our moderated mediation models were tested via structural equation modeling (N = 609). We found that college students' exposure to social media prodrinking messages indirectly influenced their binge drinking intentions via perceived injunctive norms, and students' identification with their peers moderated this indirect effect. However, neither descriptive nor injunctive norms mediated the influence of students' exposure to TV prodrinking messages on their binge drinking intentions. Theoretical and practical implications of the findings are discussed.

  12. Perceived parental monitoring and adolescent internet addiction: A moderated mediation model.

    Science.gov (United States)

    Ding, Qingwen; Li, Dongping; Zhou, Yueyue; Dong, Hongning; Luo, Jinjing

    2017-11-01

    Bronfenbrenner's (1979) ecological model focuses on the interrelation between different contexts and the interaction between individuals and their proximal contexts. Based on this theory, the present study tested a moderated mediation model of family, peer, and individual characteristics to investigate how they impact adolescent Internet addiction. Specifically, we examined whether deviant peer affiliation partially mediated the relation between perceived parental monitoring and adolescent Internet addiction, and whether this indirect relation was moderated by effortful control. A total of 747 Chinese middle school students filled out anonymous questionnaires concerning perceived parental monitoring, deviant peer affiliation, effortful control, and Internet addiction. The findings indicated that while the impact of parental monitoring on Internet addiction was partially mediated by deviant peer affiliation, effortful control moderated the first stage of the indirect relationship. For low effortful control adolescents, perceived parental monitoring negatively predicted deviant peer affiliation. Conversely, the indirect path was not significant for high effortful control adolescents. These findings highlight the need to consider family, peer and individual factors simultaneously when evaluating risks associated with adolescent Internet addiction and have important implications for the prevention and intervention of adolescent Internet addiction. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Associations between a Leader's Work Passion and an Employee's Work Passion: A Moderated Mediation Model.

    Science.gov (United States)

    Li, Jingjing; Zhang, Jian; Yang, Zhiguo

    2017-01-01

    Based on the theory of emotional contagion and goal content, this study explored the positive associations between a leader's work passion and employees' work passion. This study investigated 364 employees and their immediate leaders from China, constructed a moderated mediation model, and used SPSS-PROCESS in conjunction with the Johnson-Neyman technique to analyze the data. The results showed that a leader's work passion was transferred to employees via emotional contagion, and the contagion process was moderated by leader-employee goal content congruence. This study provides a potential way to stimulate employees' work passion from the perspective of leader-employee interactions. Moreover, the limitations of the study and potential topics for future research are discussed.

  14. Structural nested mean models for assessing time-varying effect moderation.

    Science.gov (United States)

    Almirall, Daniel; Ten Have, Thomas; Murphy, Susan A

    2010-03-01

    This article considers the problem of assessing causal effect moderation in longitudinal settings in which treatment (or exposure) is time varying and so are the covariates said to moderate its effect. Intermediate causal effects that describe time-varying causal effects of treatment conditional on past covariate history are introduced and considered as part of Robins' structural nested mean model. Two estimators of the intermediate causal effects, and their standard errors, are presented and discussed: The first is a proposed two-stage regression estimator. The second is Robins' G-estimator. The results of a small simulation study that begins to shed light on the small versus large sample performance of the estimators, and on the bias-variance trade-off between the two estimators are presented. The methodology is illustrated using longitudinal data from a depression study.

  15. Moderated Mediation Model of Interrelations between Workplace Romance, Wellbeing, and Employee Performance

    Directory of Open Access Journals (Sweden)

    Muhammad Aamir Shafique Khan

    2017-12-01

    Full Text Available In this study, first we examined the effect of workplace romance on employee job performance, and the mediatory role of psychological wellbeing in the relationship between workplace romance and employee performance. Then we tested the moderating effects of gender and workplace romance type – lateral or hierarchical – on the indirect effect of workplace romance on employee performance. Based on a survey of 311 doctors from five government teaching hospitals in Pakistan, we used structural equation modeling and bootstrapping to test these relationships. This study reveals that psychological wellbeing significantly fully mediates the positive relationship between workplace romance and job performance. Moreover, multi-group analysis shows that gender moderates the indirect effect of workplace romance on employee performance, where the indirect effect of workplace romance on employee performance is stronger for male participants. This study carries important implications, particularly for the policy makers and managers of healthcare sector organizations.

  16. Moderated Mediation Model of Interrelations between Workplace Romance, Wellbeing, and Employee Performance.

    Science.gov (United States)

    Khan, Muhammad Aamir Shafique; Jianguo, Du; Usman, Muhammad; Ahmad, Malik I

    2017-01-01

    In this study, first we examined the effect of workplace romance on employee job performance, and the mediatory role of psychological wellbeing in the relationship between workplace romance and employee performance. Then we tested the moderating effects of gender and workplace romance type - lateral or hierarchical - on the indirect effect of workplace romance on employee performance. Based on a survey of 311 doctors from five government teaching hospitals in Pakistan, we used structural equation modeling and bootstrapping to test these relationships. This study reveals that psychological wellbeing significantly fully mediates the positive relationship between workplace romance and job performance. Moreover, multi-group analysis shows that gender moderates the indirect effect of workplace romance on employee performance, where the indirect effect of workplace romance on employee performance is stronger for male participants. This study carries important implications, particularly for the policy makers and managers of healthcare sector organizations.

  17. Associations between a Leader's Work Passion and an Employee's Work Passion: A Moderated Mediation Model

    Directory of Open Access Journals (Sweden)

    Jingjing Li

    2017-08-01

    Full Text Available Based on the theory of emotional contagion and goal content, this study explored the positive associations between a leader's work passion and employees' work passion. This study investigated 364 employees and their immediate leaders from China, constructed a moderated mediation model, and used SPSS-PROCESS in conjunction with the Johnson-Neyman technique to analyze the data. The results showed that a leader's work passion was transferred to employees via emotional contagion, and the contagion process was moderated by leader–employee goal content congruence. This study provides a potential way to stimulate employees' work passion from the perspective of leader–employee interactions. Moreover, the limitations of the study and potential topics for future research are discussed.

  18. A prediction model based on an artificial intelligence system for moderate to severe obstructive sleep apnea.

    Science.gov (United States)

    Sun, Lei Ming; Chiu, Hung-Wen; Chuang, Chih Yuan; Liu, Li

    2011-09-01

    Obstructive sleep apnea (OSA) is a major concern in modern medicine; however, it is difficult to diagnose. Screening questionnaires such as the Berlin questionnaire, Rome questionnaire, and BASH'IM score are used to identify patients with OSA. However, the sensitivity and specificity of these tools are not satisfactory. We aim to introduce an artificial intelligence method to screen moderate to severe OSA patients (apnea-hypopnea index ≧15). One hundred twenty patients were asked to complete a newly developed questionnaire before undergoing an overnight polysomnography (PSG) study. One hundred ten validated questionnaires were enrolled in this study. Genetic algorithm (GA) was used to build the five best models based on these questionnaires. The same data were analyzed with logistic regression (LR) for comparison. The sensitivity of the GA models varied from 81.8% to 88.0%, with a specificity of 95% to 97%. On the other hand, the sensitivity and specificity of the LR model were 55.6% and 57.9%, respectively. GA provides a good solution to build models for screening moderate to severe OSA patients, who require PSG evaluation and medical intervention. The questionnaire did not require any special biochemistry data and was easily self-administered. The sensitivity and specificity of the GA models are satisfactory and may improve when more patients are recruited.

  19. Association between a parent’s brand passion and a child’s brand passion: a moderated moderated-mediation model

    Directory of Open Access Journals (Sweden)

    Gilal FG

    2018-04-01

    Full Text Available Faheem Gul Gilal,1 Jian Zhang,1 Naeem Gul Gilal,2 Rukhsana Gul Gilal3 1Donlinks School of Economics and Management, University of Science and Technology Beijing, Beijing 100083, People’s Republic of China; 2School of Management, Huazhong University of Science and Technology, Wuhan, Hubei 430074, People’s Republic of China; 3Department of Business Administration, Sukkur IBA University, Sukkur, Sindh, Pakistan Purpose: Both marketing scholars and brand managers have noted the importance of brand passion. They have increasingly emphasized how brand passion influences consumers’ psychological states and behaviors. In contrast, an almost negligible effort has been made to study whether the individual’s brand passion can be transferred to others.Methods: Using consumer socialization theory and emotional contagion theory as a lens, this study explores whether airline brand passion can be transferred from a parent to a child. To this end, a convenience sample of (N = 202 parent-child dyads was utilized to test the moderated moderated-mediation hypotheses. Results: The results provide evidence that parents’ airline passion can be translated into the child’s airline passion via emotional contagion for daughters who live with their parents but not those who live independently of their parents. Similarly, parents’ airline passion can be transferred to sons regardless of their geographical distance. The implications, limitations, and agendas for future research are discussed in depth. Keywords: parent’s airline passion, child’s airline passion, emotional contagion, geographical distance, moderated moderated-mediation model

  20. Quantifying the relevance of adaptive thermal comfort models in moderate thermal climate zones

    Energy Technology Data Exchange (ETDEWEB)

    Hoof, Joost van; Hensen, Jan L.M. [Faculty of Architecture, Building and Planning, Technische Universiteit Eindhoven, Vertigo 6.18, P.O. Box 513, 5600 MB Eindhoven (Netherlands)

    2007-01-15

    Standards governing thermal comfort evaluation are on a constant cycle of revision and public review. One of the main topics being discussed in the latest round was the introduction of an adaptive thermal comfort model, which now forms an optional part of ASHRAE Standard 55. Also on a national level, adaptive thermal comfort guidelines come into being, such as in the Netherlands. This paper discusses two implementations of the adaptive comfort model in terms of usability and energy use for moderate maritime climate zones by means of literature study, a case study comprising temperature measurements, and building performance simulation. It is concluded that for moderate climate zones the adaptive model is only applicable during summer months, and can reduce energy for naturally conditioned buildings. However, the adaptive thermal comfort model has very limited application potential for such climates. Additionally we suggest a temperature parameter with a gradual course to replace the mean monthly outdoor air temperature to avoid step changes in optimum comfort temperatures. (author)

  1. Perceiving a calling, living a calling, and job satisfaction: testing a moderated, multiple mediator model.

    Science.gov (United States)

    Duffy, Ryan D; Bott, Elizabeth M; Allan, Blake A; Torrey, Carrie L; Dik, Bryan J

    2012-01-01

    The current study examined the relation between perceiving a calling, living a calling, and job satisfaction among a diverse group of employed adults who completed an online survey (N = 201). Perceiving a calling and living a calling were positively correlated with career commitment, work meaning, and job satisfaction. Living a calling moderated the relations of perceiving a calling with career commitment and work meaning, such that these relations were more robust for those with a stronger sense they were living their calling. Additionally, a moderated, multiple mediator model was run to examine the mediating role of career commitment and work meaning in the relation of perceiving a calling and job satisfaction, while accounting for the moderating role of living a calling. Results indicated that work meaning and career commitment fully mediated the relation between perceiving a calling and job satisfaction. However, the indirect effects of work meaning and career commitment were only significant for individuals with high levels of living a calling, indicating the importance of living a calling in the link between perceiving a calling and job satisfaction. Implications for research and practice are discussed. (c) 2012 APA, all rights reserved.

  2. Intrinsic and extrinsic goals as moderators of stress and depressive symptoms in Chinese undergraduate students: A multi-wave longitudinal study.

    Science.gov (United States)

    Ling, Yu; He, Yushu; Wei, Yong; Cen, Weihong; Zhou, Qi; Zhong, Mingtian

    2016-05-11

    Studies in western countries have examined the specific vulnerability hypothesis of Dykman's theory of goal-orientation predispositions to depression through two-time point designs. The purpose of this prospective longitudinal study was to investigate the moderating effects of intrinsic and extrinsic goals on stress and depressive symptoms in Chinese undergraduate students. A total of 462 undergraduate students [46% female; mean age, 19.06 (range, 17-22) years] completed self-reported measures assessing intrinsic and extrinsic goals, depressive symptoms, and the occurrence of social and academic hassles. Every 3 months over the subsequent 12 months, the undergraduate students completed measures assessing depressive symptoms and the occurrence of daily hassles. Results of hierarchical linear modeling analyses indicated that undergraduate students with low levels of intrinsic goals reported greater depressive symptoms following the occurrence of social and academic hassles than did those with high levels of such goals. However, undergraduate students with high levels of extrinsic goals did not report greater depressive symptoms following the occurrence of social and academic hassles than did those possessing low levels. These findings suggest that intrinsic goals can protect undergraduate students experiencing high levels of social and academic hassles from depressive symptoms. The study findings provide new insight into the course of depressive symptoms among undergraduate students, and offer psychologist and psychiatrists ways to protect individuals from depressive symptoms by building up intrinsic goals.

  3. Task stressfulness moderates the effects of verbal person centeredness on cardiovascular reactivity: a dual-process account of the reactivity hypothesis.

    Science.gov (United States)

    Bodie, Graham D

    2012-01-01

    This study sought to investigate the impact of person-centered comfort on cardiovascular reactivity and to test a recently developed dual-process theory of supportive message outcomes proposing that the impact of supportive communication is moderated by the motivation and ability to attend to message content. Participants (n = 179) completed a public speaking task that served to experimentally manipulate stress. During the preparation period, instant messages containing either low or high person-centered messages or containing no imbedded supportive message were sent. Results indicated that, in line with theoretical predictions, message content did influence mean arterial pressure and heart rate for participants exposed to moderate but not to low or high stress. Results are discussed in terms of the dual-process theory of supportive message outcomes, and the discussion offers both theoretical and practical implications of the research.

  4. The Culture-Work-Health Model and Work Stress.

    Science.gov (United States)

    Peterson, Michael; Wilson, John F.

    2002-01-01

    Examines the role of organizational culture in the etiology of workplace stress through the framework of the Culture-Work- Health model. A review of relevant business and health literature indicates that culture is an important component of work stress and may be a key to creating effective organizational stress interventions. (SM)

  5. Soil Compressibility Models for a Wide Stress Range

    KAUST Repository

    Chong, Song-Hun

    2016-03-03

    Soil compressibility models with physically correct asymptotic void ratios are required to analyze situations that involve a wide stress range. Previously suggested models and other functions are adapted to satisfy asymptotic void ratios at low and high stress levels; all updated models involve four parameters. Compiled consolidation data for remolded and natural clays are used to test the models and to develop correlations between model parameters and index properties. Models can adequately fit soil compression data for a wide range of stresses and soil types; in particular, models that involve the power of the stress σ\\'β display higher flexibility to capture the brittle response of some natural soils. The use of a single continuous function avoids numerical discontinuities or the need for ad hoc procedures to determine the yield stress. The tangent stiffness-readily computed for all models-should not be mistaken for the small-strain constant-fabric stiffness. © 2016 American Society of Civil Engineers.

  6. Moderating Nutritious Habits in Psychiatric Patients Using Transtheoretical Model of Change and Counseling.

    Science.gov (United States)

    Anastopoulou, Konstantina; Fradelos, Evangelos C; Misouridou, Evdokia; Kourakos, Michael; Berk, Aristea; Papathanasiou, Ioanna V; Kleisiaris, Christos; Zyga, Sofia

    2017-01-01

    Motivational Interviewing provides the opportunity to health professionals to have an effective strategy to increase the level of readiness to change health behaviors. Along with the Transtheoretical Model (Stages of Change Model) compose the theoretical base of intervention in psychiatry settings. This study was aimed to change nutritious behavior of psychiatric patients using a specific Model of Change and Counseling implementing a health education program. A quasi-experimental design was adopted on a random sample of 60 psychiatric patients at Military Hospital of Athens. Patients were divided into two groups as follows; (a) Intervention Group (four sessions of counseling and encouraging motivation for modification of their nutritious habits), and (b) Control Group (simple information sessions about the principles of healthy alimentation). The mean age of Intervention Group (IG) was 43.9 ± 9.5 and Control Group (CG) 46.1 ± 9.1, ranging from 40 to 55 years old. Also, 26.7% of the participants were female, 23.3% were married and, 10% divorced. Our analyses showed that IG patients were significantly loss weight post-intervention compared to CG patients. Specifically, IG patients were significantly moderated the intake of starchy foods in every meal (p moderated the intake of low fat dairy foods while they changed the full fat dairy foods with low fat (p moderating unhealthy nutritious behaviors (p = 0.032). Our results confirms that health educational and promotional Interventions may change behavior of psychiatric patients and thus may positively influence their nutritious habits.

  7. Swell impact on wind stress and atmospheric mixing in a regional coupled atmosphere-wave model

    DEFF Research Database (Denmark)

    Wu, Lichuan; Rutgersson, Anna; Sahlée, Erik

    2016-01-01

    Over the ocean, the atmospheric turbulence can be significantly affected by swell waves. Change in the atmospheric turbulence affects the wind stress and atmospheric mixing over swell waves. In this study, the influence of swell on atmospheric mixing and wind stress is introduced into an atmosphere-wave-coupled...... regional climate model, separately and combined. The swell influence on atmospheric mixing is introduced into the atmospheric mixing length formula by adding a swell-induced contribution to the mixing. The swell influence on the wind stress under wind-following swell, moderate-range wind, and near......-neutral and unstable stratification conditions is introduced by changing the roughness length. Five year simulation results indicate that adding the swell influence on atmospheric mixing has limited influence, only slightly increasing the near-surface wind speed; in contrast, adding the swell influence on wind stress...

  8. Stress-reducing preventive maintenance model for a unit under stressful environment

    International Nuclear Information System (INIS)

    Park, J.H.; Chang, Woojin; Lie, C.H.

    2012-01-01

    We develop a preventive maintenance (PM) model for a unit operated under stressful environment. The PM model in this paper consists of a failure rate model and two cost models to determine the optimal PM scheduling which minimizes a cost rate. The assumption for the proposed model is that stressful environment accelerates the failure of the unit and periodic maintenances reduce stress from outside. The failure rate model handles the maintenance effect of PM using improvement and stress factors. The cost models are categorized into two failure recognition cases: immediate failure recognition and periodic failure detection. The optimal PM scheduling is obtained by considering the trade-off between the related cost and the lifetime of a unit in our model setting. The practical usage of our proposed model is tested through a numerical example.

  9. Modeling heat stress under different environmental conditions.

    Science.gov (United States)

    Carabaño, M J; Logar, B; Bormann, J; Minet, J; Vanrobays, M-L; Díaz, C; Tychon, B; Gengler, N; Hammami, H

    2016-05-01

    Renewed interest in heat stress effects on livestock productivity derives from climate change, which is expected to increase temperatures and the frequency of extreme weather events. This study aimed at evaluating the effect of temperature and humidity on milk production in highly selected dairy cattle populations across 3 European regions differing in climate and production systems to detect differences and similarities that can be used to optimize heat stress (HS) effect modeling. Milk, fat, and protein test day data from official milk recording for 1999 to 2010 in 4 Holstein populations located in the Walloon Region of Belgium (BEL), Luxembourg (LUX), Slovenia (SLO), and southern Spain (SPA) were merged with temperature and humidity data provided by the state meteorological agencies. After merging, the number of test day records/cows per trait ranged from 686,726/49,655 in SLO to 1,982,047/136,746 in BEL. Values for the daily average and maximum temperature-humidity index (THIavg and THImax) ranges for THIavg/THImax were largest in SLO (22-74/28-84) and shortest in SPA (39-76/46-83). Change point techniques were used to determine comfort thresholds, which differed across traits and climatic regions. Milk yield showed an inverted U-shaped pattern of response across the THI scale with a HS threshold around 73 THImax units. For fat and protein, thresholds were lower than for milk yield and were shifted around 6 THI units toward larger values in SPA compared with the other countries. Fat showed lower HS thresholds than protein traits in all countries. The traditional broken line model was compared with quadratic and cubic fits of the pattern of response in production to increasing heat loads. A cubic polynomial model allowing for individual variation in patterns of response and THIavg as heat load measure showed the best statistical features. Higher/lower producing animals showed less/more persistent production (quantity and quality) across the THI scale. The

  10. Procrastination and suicide proneness: A moderated-mediation model for cognitive schemas and gender.

    Science.gov (United States)

    Klibert, Jeffrey; LeLeux-LaBarge, Kayla; Tarantino, Nicholas; Yancey, Thresa; Lamis, Dorian A

    2016-07-01

    This study examined the direct and indirect paths between procrastination and suicide proneness while considering gender differences. Participants included 547 undergraduates from a southeastern university. Procrastination was positively related to suicide proneness for both genders, although this relation was stronger for women. Moderated-mediation analyses with bootstrapping highlighted insufficient self-control schemas as a mediator in the relation between procrastination and suicide proneness. However, indirect pathways did not vary by gender. Results represent an extension of the Procrastination-Health Model by highlighting the contribution of cognitive factors in explaining the relation between procrastination and suicide proneness.

  11. Time-varying effect moderation using the structural nested mean model: estimation using inverse-weighted regression with residuals

    Science.gov (United States)

    Almirall, Daniel; Griffin, Beth Ann; McCaffrey, Daniel F.; Ramchand, Rajeev; Yuen, Robert A.; Murphy, Susan A.

    2014-01-01

    This article considers the problem of examining time-varying causal effect moderation using observational, longitudinal data in which treatment, candidate moderators, and possible confounders are time varying. The structural nested mean model (SNMM) is used to specify the moderated time-varying causal effects of interest in a conditional mean model for a continuous response given time-varying treatments and moderators. We present an easy-to-use estimator of the SNMM that combines an existing regression-with-residuals (RR) approach with an inverse-probability-of-treatment weighting (IPTW) strategy. The RR approach has been shown to identify the moderated time-varying causal effects if the time-varying moderators are also the sole time-varying confounders. The proposed IPTW+RR approach provides estimators of the moderated time-varying causal effects in the SNMM in the presence of an additional, auxiliary set of known and measured time-varying confounders. We use a small simulation experiment to compare IPTW+RR versus the traditional regression approach and to compare small and large sample properties of asymptotic versus bootstrap estimators of the standard errors for the IPTW+RR approach. This article clarifies the distinction between time-varying moderators and time-varying confounders. We illustrate the methodology in a case study to assess if time-varying substance use moderates treatment effects on future substance use. PMID:23873437

  12. Effective Stress Management: A Model of Emotional Intelligence, Self-Leadership, and Student Stress Coping

    Science.gov (United States)

    Houghton, Jeffery D.; Wu, Jinpei; Godwin, Jeffrey L.; Neck, Christopher P.; Manz, Charles C.

    2012-01-01

    This article develops and presents a model of the relationships among emotional intelligence, self-leadership, and stress coping among management students. In short, the authors' model suggests that effective emotion regulation and self-leadership, as mediated through positive affect and self-efficacy, has the potential to facilitate stress coping…

  13. Modeling the Effects of Stress: An Approach to Training

    Science.gov (United States)

    Cuper, Taryn

    2010-01-01

    Stress is an integral element of the operational conditions experienced by combat medics. The effects of stress can compromise the performance of combat medics who must reach and treat their comrades under often threatening circumstances. Examples of these effects include tunnel vision, loss of motor control, and diminished hearing, which can result in an inability to perceive further danger, satisfactorily treat the casualty, and communicate with others. While many training programs strive to recreate this stress to aid in the experiential learning process, stress inducement may not always be feasible or desired. In addition, live simulations are not always a practical, convenient, and repeatable method of training. Instead, presenting situational training on a personal computer is proposed as an effective training platform in which the effects of stress can be addressed in a different way. We explore the cognitive and motor effects of stress, as well as the benefits of training for mitigating these effects in real life. While many training applications focus on inducing stress in order to "condition" the stress response, the author explores the possibilities of modeling stress to produce a similar effect. Can presenting modeled effects of stress help prepare or inoculate soldiers for stressful situations in which they must perform at a high level? This paper investigates feasibility of modeling stress and describes the preliminary design considerations of a combat medic training system that utilizes this method of battlefield preparation.

  14. Improvement and Validation of Weld Residual Stress Modelling Procedure

    International Nuclear Information System (INIS)

    Zang, Weilin; Gunnars, Jens; Dong, Pingsha; Hong, Jeong K.

    2009-06-01

    The objective of this work is to identify and evaluate improvements for the residual stress modelling procedure currently used in Sweden. There is a growing demand to eliminate any unnecessary conservatism involved in residual stress assumptions. The study was focused on the development and validation of an improved weld residual stress modelling procedure, by taking advantage of the recent advances in residual stress modelling and stress measurement techniques. The major changes applied in the new weld residual stress modelling procedure are: - Improved procedure for heat source calibration based on use of analytical solutions. - Use of an isotropic hardening model where mixed hardening data is not available. - Use of an annealing model for improved simulation of strain relaxation in re-heated material. The new modelling procedure is demonstrated to capture the main characteristics of the through thickness stress distributions by validation to experimental measurements. Three austenitic stainless steel butt-welds cases are analysed, covering a large range of pipe geometries. From the cases it is evident that there can be large differences between the residual stresses predicted using the new procedure, and the earlier procedure or handbook recommendations. Previously recommended profiles could give misleading fracture assessment results. The stress profiles according to the new procedure agree well with the measured data. If data is available then a mixed hardening model should be used

  15. Improvement and Validation of Weld Residual Stress Modelling Procedure

    Energy Technology Data Exchange (ETDEWEB)

    Zang, Weilin; Gunnars, Jens (Inspecta Technology AB, Stockholm (Sweden)); Dong, Pingsha; Hong, Jeong K. (Center for Welded Structures Research, Battelle, Columbus, OH (United States))

    2009-06-15

    The objective of this work is to identify and evaluate improvements for the residual stress modelling procedure currently used in Sweden. There is a growing demand to eliminate any unnecessary conservatism involved in residual stress assumptions. The study was focused on the development and validation of an improved weld residual stress modelling procedure, by taking advantage of the recent advances in residual stress modelling and stress measurement techniques. The major changes applied in the new weld residual stress modelling procedure are: - Improved procedure for heat source calibration based on use of analytical solutions. - Use of an isotropic hardening model where mixed hardening data is not available. - Use of an annealing model for improved simulation of strain relaxation in re-heated material. The new modelling procedure is demonstrated to capture the main characteristics of the through thickness stress distributions by validation to experimental measurements. Three austenitic stainless steel butt-welds cases are analysed, covering a large range of pipe geometries. From the cases it is evident that there can be large differences between the residual stresses predicted using the new procedure, and the earlier procedure or handbook recommendations. Previously recommended profiles could give misleading fracture assessment results. The stress profiles according to the new procedure agree well with the measured data. If data is available then a mixed hardening model should be used

  16. Upper crustal stress and seismotectonics of the Garhwal Himalaya using small-to-moderate earthquakes: Implications to the local structures and free fluids

    Science.gov (United States)

    Prasath, R. Arun; Paul, Ajay; Singh, Sandeep

    2017-03-01

    The work presents new focal-mechanism data of small-to-moderate (3.0 ⩾ ML ⩽ 5.0) upper crustal earthquakes for the Garhwal Himalaya from a local seismic network installed in July 2007. Majority of the epicenters of these earthquakes are located close to the Main Central Thrust (MCT) zone. We retrieved Moment Tensor (MT) solutions of 26 earthquakes by waveform inversion. The MT results and 11 small-to-moderate earthquakes from the published records are used for stress inversions. The MT solutions reveal dominatingly thrust mechanisms with few strike slip earthquakes near Chamoli. The seismic cross sections illustrate that, these earthquakes are located around the Mid-Crustal-Ramp (MCR) in the detachment. The optimally oriented faults from stress inversions suggest that, the seismogenic fault in this region is similar to a fault plane having dip angle between 12 and 25 degrees, which is compatible with the dip angle of the MCR (∼16°) in this region. P-axes and the maximum horizontal compressive stress are NE-SW oriented; the direction of the relative motion of Indian plate with respect to the Eurasian plate. The Friction Coefficient estimated from stress inversions show that the Chamoli region having low friction in comparison to the overall values. The free fluids trapped beneath the detachment are penetrating into the local faults, hence, decreasing the frictional strength and altering the prevailing stress conditions of the surroundings. The present study reveals that the MCR structure is seismogenically active and producing the small-moderate earthquakes in the region, while the MCT is probably dormant at present.

  17. Modeling of stresses at grain boundaries with respect to occurrence of stress corrosion cracking

    Energy Technology Data Exchange (ETDEWEB)

    Kozaczek, K.J. [Oak Ridge National Lab., TN (United States); Sinharoy, A.; Ruud, C.O. [Pennsylvania State Univ., University Park, PA (United States); McIlree, A.R. [Electric Power Research Institute, Palo Alto, CA (United States)

    1995-12-31

    The distributions of elastic stresses/strains in the grain boundary regions were studied by the analytical and the finite element models. The grain boundaries represent the sites where stress concentration occurs as a result of discontinuity of elastic properties across the grain boundary and the presence of second phase particles elastically different from the surrounding matrix grains. A quantitative analysis of those stresses for steels and nickel based alloys showed that the stress concentrations in the grain boundary regions are high enough to cause a local microplastic deformation even when the material is in the macroscopic elastic regime. The stress redistribution as a result of such a plastic deformation was discussed.

  18. Social modeling of eating mediated by mirror neuron activity: A causal model moderated by frontal asymmetry and BMI.

    Science.gov (United States)

    McGeown, Laura; Davis, Ron

    2018-02-15

    The social modeling of eating effect refers to the consistently demonstrated phenomenon that individuals tend to match their quantity of food intake to their eating companion. The current study sought to explore whether activity within the mirror neuron system (MNS) mediates the social modeling of eating effect as a function of EEG frontal asymmetry and body mass index (BMI). Under the guise of rating empathy, 93 female undergraduates viewed a female video confederate "incidentally" consume either a low or high intake of chips while electroencephalogram (EEG) activity was recorded. Subsequent ad libitum chip consumption was quantified. A first- and second-stage dual moderation model revealed that frontal asymmetry and BMI moderated an indirect effect of model consumption on participants' food consumption as mediated by MNS activity at electrode site C3, a 3 b 3 =-0.718, SE=0.365, 95% CI [-1.632, -0.161]. Left frontal asymmetry was associated with greater mu activity and a positive association between model and participant chip consumption, while right frontal asymmetry was associated with less mu activity and a negative association between model and participant consumption. Across all levels of frontal asymmetry, the effect was only significant among those with a BMI at the 50th percentile or lower. Thus, among leaner individuals, the MNS was demonstrated to mediate social modeling of eating, as moderated by frontal asymmetry. These findings are integrated within the normative account of social modeling of eating. It is proposed that the normative framework may benefit from consideration of both conscious and unconscious operation of intake norms. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Stress generation in adolescence: Contributions from five-factor model (FFM) personality traits and childhood maltreatment.

    Science.gov (United States)

    Kushner, Shauna C; Bagby, R Michael; Harkness, Kate L

    2017-04-01

    Youth with depression are theorized to generate stress in their lives because of a complex interaction between their personal characteristics and their chronic environmental context. Using a moderated regression approach, we provided a novel test of this hypothesis by examining whether adolescent 5-factor model personality traits moderate the associations between early emotional, physical, and sexual maltreatment and life events experienced in the past 6 months. Participants in this cross-sectional study were 110 adolescents (M = 16.24, SD = 1.53, age range = 13-17, 74.5% female) with major depressive disorder. The relation of physical maltreatment to dependent interpersonal life events was moderated by extraversion. Among physically maltreated youth, dependent interpersonal events were positively associated with extraversion. Further, the relation of sexual maltreatment to independent events were moderated by extraversion and agreeableness. Among sexually maltreated youth, independent events were negatively associated with extraversion and positively associated with agreeableness. The observed vulnerability-risk interactions are discussed in terms of their implications for understanding the role of stress generation mechanisms in an integrated model of depression. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  20. Moderating effects of a postdisaster intervention on risk and resilience factors associated with posttraumatic stress disorder in Chinese children.

    Science.gov (United States)

    Fu, Christine; Leoutsakos, Jeannie-Marie; Underwood, Carol

    2013-12-01

    This study is an evaluation of a psychosocial intervention involving child and adolescent survivors of the 2008 Sichuan China earthquake. Sociodemographics, earthquake-related risk exposure, resilience using the Connor-Davidson Resilience Scale, and posttraumatic stress disorder (PTSD) using the UCLA-PTSD Index were collected from 1,988 intervention participants and 2,132 controls. Mean resilience scores and the odds of PTSD did not vary between groups. The independent factors for risk and resilience and the dependent variable, PTSD, in the measurement models between control and intervention groups were equivalent. The structural model of risk and 2 resilience factors on PTSD was examined and found to be unequivalent between groups. In contrast to controls, risk exposure (B = −0.32, p Rational thinking (B = −0.48, p < .001), a resilience factor, was more negatively associated with PTSD in the intervention group. The second resilience factor explored, self-awareness, was positively associated with PTSD in both groups (B = 0.46 for controls, p < .001, and B = 0.69 for intervention, p < .001). Results highlight the need for more cross-cultural research in resilience theory to develop culturally appropriate interventions and evaluation measures.

  1. Effect of mild-to-moderate smoking on viral load, cytokines, oxidative stress, and cytochrome P450 enzymes in HIV-infected individuals.

    Directory of Open Access Journals (Sweden)

    Anusha Ande

    Full Text Available Mild-to-moderate tobacco smoking is highly prevalent in HIV-infected individuals, and is known to exacerbate HIV pathogenesis. The objective of this study was to determine the specific effects of mild-to-moderate smoking on viral load, cytokine production, and oxidative stress and cytochrome P450 (CYP pathways in HIV-infected individuals who have not yet received antiretroviral therapy (ART. Thirty-two human subjects were recruited and assigned to four different cohorts as follows: a HIV negative non-smokers, b HIV positive non-smokers, c HIV negative mild-to-moderate smokers, and d HIV positive mild-to-moderate smokers. Patients were recruited in Cameroon, Africa using strict selection criteria to exclude patients not yet eligible for ART and not receiving conventional or traditional medications. Those with active tuberculosis, hepatitis B or with a history of substance abuse were also excluded. Our results showed an increase in the viral load in the plasma of HIV positive patients who were mild-to-moderate smokers compared to individuals who did not smoke. Furthermore, although we did not observe significant changes in the levels of most pro-inflammatory cytokines, the cytokine IL-8 and MCP-1 showed a significant decrease in the plasma of HIV-infected patients and smokers compared with HIV negative non-smokers. Importantly, HIV-infected individuals and smokers showed a significant increase in oxidative stress compared with HIV negative non-smoker subjects in both plasma and monocytes. To examine the possible pathways involved in increased oxidative stress and viral load, we determined the mRNA levels of several antioxidant and cytochrome P450 enzymes in monocytes. The results showed that the levels of most antioxidants are unaltered, suggesting their inability to counter oxidative stress. While CYP2A6 was induced in smokers, CYP3A4 was induced in HIV and HIV positive smokers compared with HIV negative non-smokers. Overall, the findings suggest

  2. Progesterone treatment shows benefit in a pediatric model of moderate to severe bilateral brain injury.

    Directory of Open Access Journals (Sweden)

    Rastafa I Geddes

    Full Text Available Controlled cortical impact (CCI models in adult and aged Sprague-Dawley (SD rats have been used extensively to study medial prefrontal cortex (mPFC injury and the effects of post-injury progesterone treatment, but the hormone's effects after traumatic brain injury (TBI in juvenile animals have not been determined. In the present proof-of-concept study we investigated whether progesterone had neuroprotective effects in a pediatric model of moderate to severe bilateral brain injury.Twenty-eight-day old (PND 28 male Sprague Dawley rats received sham (n = 24 or CCI (n = 47 injury and were given progesterone (4, 8, or 16 mg/kg per 100 g body weight or vehicle injections on post-injury days (PID 1-7, subjected to behavioral testing from PID 9-27, and analyzed for lesion size at PID 28.The 8 and 16 mg/kg doses of progesterone were observed to be most beneficial in reducing the effect of CCI on lesion size and behavior in PND 28 male SD rats.Our findings suggest that a midline CCI injury to the frontal cortex will reliably produce a moderate TBI comparable to what is seen in the adult male rat and that progesterone can ameliorate the injury-induced deficits.

  3. Prospective memory after moderate-to-severe traumatic brain injury: a multinomial modeling approach.

    Science.gov (United States)

    Pavawalla, Shital P; Schmitter-Edgecombe, Maureen; Smith, Rebekah E

    2012-01-01

    Prospective memory (PM), which can be understood as the processes involved in realizing a delayed intention, is consistently found to be impaired after a traumatic brain injury (TBI). Although PM can be empirically dissociated from retrospective memory, it inherently involves both a prospective component (i.e., remembering that an action needs to be carried out) and retrospective components (i.e., remembering what action needs to be executed and when). This study utilized a multinomial processing tree model to disentangle the prospective (that) and retrospective recognition (when) components underlying PM after moderate-to-severe TBI. Seventeen participants with moderate to severe TBI and 17 age- and education-matched control participants completed an event-based PM task that was embedded within an ongoing computer-based color-matching task. The multinomial processing tree modeling approach revealed a significant group difference in the prospective component, indicating that the control participants allocated greater preparatory attentional resources to the PM task compared to the TBI participants. Participants in the TBI group were also found to be significantly more impaired than controls in the when aspect of the retrospective component. These findings indicated that the TBI participants had greater difficulty allocating the necessary preparatory attentional resources to the PM task and greater difficulty discriminating between PM targets and nontargets during task execution, despite demonstrating intact posttest recall and/or recognition of the PM tasks and targets.

  4. A Moderator Model of Alcohol Use and Dating Aggression among Young Adults.

    Science.gov (United States)

    Collibee, Charlene; Furman, Wyndol

    2018-03-01

    Dating aggression has been identified as a priority public health concern. Although alcohol use is a known robust risk factor for dating aggression involvement, such usage is neither necessary nor sufficient for dating aggression involvement. As such, a growing topic of interest is a better understanding of when, and for whom, alcohol use increases risk. A theoretical moderator model posits that associations between alcohol use and dating aggression involvement vary depending on both background (e.g., psychopathology) and situational (e.g., relationship characteristics) risk factors. Alcohol use is thought to be more strongly associated with dating aggression in the context of these other risk factors. Using an intensive longitudinal design, we collected six waves of data spanning 6 months from 120 participants (60 females; M age W1 = 22.44). Alcohol use and relationship risk were both associated with increases in dating aggression involvement. Consistent with a moderator model, interactions emerged between alcohol use and relationship risk for subsequent dating aggression involvement. The findings underscore the importance of alcohol use and relationship risk for the development of intervention and prevention programs.

  5. Emotional closeness to parents and grandparents: A moderated mediation model predicting adolescent adjustment.

    Science.gov (United States)

    Attar-Schwartz, Shalhevet

    2015-09-01

    Warm and emotionally close relationships with parents and grandparents have been found in previous studies to be linked with better adolescent adjustment. The present study, informed by Family Systems Theory and Intergenerational Solidarity Theory, uses a moderated mediation model analyzing the contribution of the dynamics of these intergenerational relationships to adolescent adjustment. Specifically, it examines the mediating role of emotional closeness to the closest grandparent in the relationship between emotional closeness to a parent (the offspring of the closest grandparent) and adolescent adjustment difficulties. The model also examines the moderating role of emotional closeness to parents in the relationship between emotional closeness to grandparents and adjustment difficulties. The study was based on a sample of 1,405 Jewish Israeli secondary school students (ages 12-18) who completed a structured questionnaire. It was found that emotional closeness to the closest grandparent was more strongly associated with reduced adjustment difficulties among adolescents with higher levels of emotional closeness to their parents. In addition, adolescent adjustment and emotional closeness to parents was partially mediated by emotional closeness to grandparents. Examining the family conditions under which adolescents' relationships with grandparents is stronger and more beneficial for them can help elucidate variations in grandparent-grandchild ties and expand our understanding of the mechanisms that shape child outcomes. (c) 2015 APA, all rights reserved).

  6. Teacher stress and health; examination of a model.

    Science.gov (United States)

    DeFrank, R S; Stroup, C A

    1989-01-01

    Stress in teaching derives from a variety of sources, and evidence exists linking such stress to physical and mental health concerns. Detailed examination of the linkages among personal factors, job stress, job satisfaction and symptomatology have not been done in this occupation, however, and the present study examines a model interrelating these variables. A survey of 245 predominantly female elementary school teachers in southeast Texas suggested that demographic factors and teaching background do not influence stress, satisfaction or health concerns. However, while job stress was the strongest predictor of job satisfaction, this stress had no direct relationship with health problems, an unexpected finding. Write-in responses by teachers indicated additional sources of stress, many of which were environmental or policy-based in nature. The implications of these findings for future research and stress management interventions for teachers are discussed.

  7. Application of a Cohesive Zone Model for Simulating Fatigue Crack Growth from Moderate to High ΔK Levels of Inconel 718

    Directory of Open Access Journals (Sweden)

    Huan Li

    2018-01-01

    Full Text Available A cyclic cohesive zone model is applied to characterize the fatigue crack growth behavior of a IN718 superalloy which is frequently used in aerospace components. In order to improve the limitation of fracture mechanics-based models, besides the predictions of the moderate fatigue crack growth rates at the Paris’ regime and the high fatigue crack growth rates at the high stress intensity factor ΔK levels, the present work is also aimed at simulating the material damage uniformly and examining the influence of the cohesive model parameters on fatigue crack growth systematically. The gradual loss of the stress-bearing ability of the material is considered through the degradation of a novel cohesive envelope. The experimental data of cracked specimens are used to validate the simulation result. Based on the reasonable estimation for the model parameters, the fatigue crack growth from moderate to high ΔK levels can be reproduced under the small-scale yielding condition, which is in fair agreement with the experimental results.

  8. Modelling of loading, stress relaxation and stress recovery in a shape memory polymer.

    Science.gov (United States)

    Sweeney, J; Bonner, M; Ward, I M

    2014-09-01

    A multi-element constitutive model for a lactide-based shape memory polymer has been developed that represents loading to large tensile deformations, stress relaxation and stress recovery at 60, 65 and 70°C. The model consists of parallel Maxwell arms each comprising neo-Hookean and Eyring elements. Guiu-Pratt analysis of the stress relaxation curves yields Eyring parameters. When these parameters are used to define the Eyring process in a single Maxwell arm, the resulting model yields at too low a stress, but gives good predictions for longer times. Stress dip tests show a very stiff response on unloading by a small strain decrement. This would create an unrealistically high stress on loading to large strain if it were modelled by an elastic element. Instead it is modelled by an Eyring process operating via a flow rule that introduces strain hardening after yield. When this process is incorporated into a second parallel Maxwell arm, there results a model that fully represents both stress relaxation and stress dip tests at 60°C. At higher temperatures a third arm is required for valid predictions. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

  9. High-protein, low-fat, short-term diet results in less stress and fatigue than moderate-protein moderate-fat diet during weight loss in male weightlifters: a pilot study.

    Science.gov (United States)

    Helms, Eric R; Zinn, Caryn; Rowlands, David S; Naidoo, Ruth; Cronin, John

    2015-04-01

    Athletes risk performance and muscle loss when dieting. Strategies to prevent losses are unclear. This study examined the effects of two diets on anthropometrics, strength, and stress in athletes. This double-blind crossover pilot study began with 14 resistance-trained males (20-43 yr) and incurred one dropout. Participants followed carbohydrate-matched, high-protein low-fat (HPLF) or moderate-protein moderate-fat (MPMF) diets of 60% habitual calories for 2 weeks. Protein intakes were 2.8g/kg and 1.6g/kg and mean fat intakes were 15.4% and 36.5% of calories, respectively. Isometric midthigh pull (IMTP) and anthropometrics were measured at baseline and completion. The Daily Analysis of Life Demands of Athletes (DALDA) and Profile of Mood States (POMS) were completed daily. Outcomes were presented statistically as probability of clinical benefit, triviality, or harm with effect sizes (ES) and qualitative assessments. Differences of effect between diets on IMTP and anthropometrics were likely or almost certainly trivial, respectively. Worse than normal scores on DALDA part A, part B and the part A "diet" item were likely more harmful (ES 0.32, 0.4 and 0.65, respectively) during MPMF than HPLF. The POMS fatigue score was likely more harmful (ES 0.37) and the POMS total mood disturbance score (TMDS) was possibly more harmful (ES 0.29) during MPMF than HPLF. For the 2 weeks observed, strength and anthropometric differences were minimal while stress, fatigue, and diet-dissatisfaction were higher during MPMF. A HPLF diet during short-term weight loss may be more effective at mitigating mood disturbance, fatigue, diet dissatisfaction, and stress than a MPMF diet.

  10. Spiritual stress and coping model of divorce: a longitudinal study.

    Science.gov (United States)

    Krumrei, Elizabeth J; Mahoney, Annette; Pargament, Kenneth I

    2011-12-01

    This study represents the first longitudinal effort to use a spiritual stress and coping model to predict adults' psychosocial adjustment following divorce. A community sample of 89 participants completed measures at the time of their divorce and 1 year later. Though the sample endorsed slightly lower levels of religiosity than the general U.S. population, most reported spiritual appraisals and positive and negative religious coping tied to divorce. Hierarchical regression analyses controlling general religiousness and nonreligious forms of coping indicated that (a) appraising divorce as a sacred loss or desecration at the time it occurred predicted more depressive symptoms and dysfunctional conflict tactics with the ex-spouse 1 year later; (b) positive religious coping reported about the year following divorce predicted greater posttraumatic growth 1 year after divorce; and (c) negative religious coping reported about the year following divorce predicted more depressive symptoms 1 year after the divorce. Bootstrapping mediation analyses indicated that negative religious coping fully mediated links between appraising the divorce as a sacred loss or desecration at the time it occurred and depressive symptoms 1 year later. In addition, moderation analyses revealed that negative religious coping is more strongly associated with depressive symptoms among those who form high versus low appraisals of their divorce as a sacred loss or desecration. These findings are relevant to divorce education and intervention provided by professionals in legal, family, mental health, and clerical roles. Implications are discussed for clinical and counseling psychology and religious communities.

  11. Polygenic risk for alcohol consumption and its association with alcohol-related phenotypes: Do stress and life satisfaction moderate these relationships?

    Science.gov (United States)

    Mies, Gabry W; Verweij, Karin J H; Treur, Jorien L; Ligthart, Lannie; Fedko, Iryna O; Hottenga, Jouke Jan; Willemsen, Gonneke; Bartels, Meike; Boomsma, Dorret I; Vink, Jacqueline M

    2018-02-01

    Genetic and environmental factors contribute about equally to alcohol-related phenotypes in adulthood. In the present study, we examined whether more stress at home or low satisfaction with life might be associated with heavier drinking or more alcohol-related problems in individuals with a high genetic susceptibility to alcohol use. Information on polygenic scores and drinking behavior was available in 6705 adults (65% female; 18-83 years) registered with the Netherlands Twin Register. Polygenic risk scores (PRSs) were constructed for all subjects based on the summary statistics of a large genome-wide association meta-analysis on alcohol consumption (grams per day). Outcome measures were quantity of alcohol consumption and alcohol-related problems assessed with the Alcohol Use Disorders Identification Test (AUDIT). Stress at home and life satisfaction were moderating variables whose significance was tested by Generalized Estimating Equation analyses taking familial relatedness, age and sex into account. PRSs for alcohol were significantly associated with quantity of alcohol consumption and alcohol-related problems in the past year (R 2 =0.11% and 0.10% respectively). Participants who reported to have experienced more stress in the past year and lower life satisfaction, scored higher on alcohol-related problems (R 2 =0.27% and 0.29 respectively), but not on alcohol consumption. Stress and life satisfaction did not moderate the association between PRSs and the alcohol outcome measures. There were significant main effects of polygenic scores and of stress and life satisfaction on drinking behavior, but there was no support for PRS-by-stress or PRS-by-life satisfaction interactions on alcohol consumption and alcohol-related problems. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  12. Meteoritic Constraints on Models of the Solar Nebula: The Abundances of Moderately Volatile Elements

    Science.gov (United States)

    Cassen, Patrick; Cuzzi, Jeff (Technical Monitor)

    1994-01-01

    The "moderately volatile" elements are those which condense (or evaporate) in the temperature range 650 - 1350 K, as a mix of material with solar abundances is cooled (or heated) tinder equilibrium conditions. Their relative abundances in chondritic meteorites are solar (or "cosmic", as defined by the composition of Cl meteorites) to within a factor of several, but vary within that range in a way that correlates remarkably well with condensation temperature, independent of chemical affinity. It has been argued that this correlation reflects a systematically selective process which favored the accretion of refractory material over volatile material from a cooling nebula. Wasson and Chou (Meteoritics 9, 69-94, 1974, and Wasson and co-authors in subsequent papers) suggested that condensation and settling of solids contemporaneously with the cooling and removal of nebular gas could produce the observed abundance patterns, but a quantitative model has been lacking. We show that the abundance patterns of the moderately volatile elements in chondritic meteorites can be produced, in some degree of quantitative detail, by models of the solar nebula that are designed to conform to observations of T Tauri stars and the global conservation laws. For example, even if the local surface density of the nebula is not decreasing, condensation and accretion of solids from radially inflowing gas in a cooling nebula can result in depletions of volatiles, relative to refractories, like those observed, The details of the calculated abundance patterns depend on (but are not especially sensitive to) model parameters, and can exhibit the variations that distinguish the meteorite classes. Thus it appears that nebula characteristics such as cooling rates, radial flow velocities, and particle accumulation rates can be quantitatively constrained by demanding that they conform to meteoritic data; and the models, in turn, can produce testable hypotheses regarding the time and location of the

  13. Sleep duration moderates the association between insula activation and risky decisions under stress in adolescents and adults.

    Science.gov (United States)

    Uy, Jessica Phuong; Galván, Adriana

    2017-01-27

    Insufficient sleep has been associated with increased risk-taking and poor decision-making, enhanced physiological responses to stress, and attenuated anterior insula (AI) activity to risk. The AI has also been linked to risky decision-making under acute stress. However, it is yet unknown how naturalistic sleep habits affect risky decision-making and AI activity when individuals feel stressed. In the current study, a daily diary approach was used to document participants' daily stress. Adolescents and adults reported their recent sleep duration and completed two fMRI visits during which they performed a risky decision-making task: once each when they endorsed a high and low level of stress. Results revealed that, regardless of age, individuals who reported receiving more sleep took fewer non-advantageous risks during high stress relative to those who reported receiving fewer hours of sleep per night while sleep duration was not associated with risky behavior under low stress. Among individuals who reported less sleep, those who exhibited reduced AI activation during risk-taking under high stress also took more disadvantageous risks whereas this effect was attenuated for those who reported longer sleep duration. Moreover, longer sleep duration was associated with greater functional coupling between the AI and dorsolateral prefrontal cortex (DLPFC) under high stress whereas sleep duration was not associated with AI-DLPFC functional coupling under low stress. These findings suggest that naturalistic sleep duration may amplify the effects of daily stress and alter risky decision-making behavior through interactions with the AI. Copyright © 2016. Published by Elsevier Ltd.

  14. Assessing a moderating effect and the global fit of a PLS model on online trading

    Directory of Open Access Journals (Sweden)

    Juan J. García-Machado

    2017-12-01

    Full Text Available This paper proposes a PLS Model for the study of Online Trading. Traditional investing has experienced a revolution due to the rise of e-trading services that enable investors to use Internet conduct secure trading. On the hand, model results show that there is a positive, direct and statistically significant relationship between personal outcome expectations, perceived relative advantage, shared vision and economy-based trust with the quality of knowledge. On the other hand, trading frequency and portfolio performance has also this relationship. After including the investor’s income and financial wealth (IFW as moderating effect, the PLS model was enhanced, and we found that the interaction term is negative and statistically significant, so, higher IFW levels entail a weaker relationship between trading frequency and portfolio performance and vice-versa. Finally, with regard to the goodness of overall model fit measures, they showed that the model is fit for SRMR and dG measures, so it is likely that the model is true.

  15. STRESS MODELING IN COMPOSITE PRODUCTS USING STANDARD OPTICALLY SENSITIVE MATERIAL

    Directory of Open Access Journals (Sweden)

    Elifkhan K. Agakhanov

    2017-01-01

    Full Text Available Abstract. Objectives The problem of physically modelling stresses in a compound solid body of revolution having a complex shape and with a complex load distribution is considered. According to the similarity criteria of stress, deformations and displacements from the volume forces decrease proportionally to the scale of similarity of geometric dimensions, which complicates their direct modelling by the photoelasticity method typically using models made from epoxy materials. Methods Based on the principle of the independent action of the forces, the initial problem is represented as the sum of two problems. In the first uniform problem, the stresses in the body of revolution from the centrifugal forces are simulated by the conventional “freezing” method. In order to solve the second nonuniform problem, the stresses in the region of the model, corresponding to the acting centrifugal forces, are “frozen”. The models are glued in a natural state at room temperature, and the compound model is annealed. Results The band patterns in sections as well as components of radial, tangential and axial stresses on contours and in sections of models are obtained by the methods of normal transmission and numerical integration of the equilibrium equation. According to the modelling criteria, the formula for the transition from stresses in models to stresses in the natural structure is established. The results of the analysis of the effect of a body's material density ratio on the stress state of the entire structure are obtained. Conclusion  Axial stresses have insignificant value as compared to radial and tangential stresses; in addition, the ratio of the densities of the compound body has both a quantitative and qualitative influence on the stress state of the structure.

  16. Secondary Traumatic Stress and Adjustment in Therapists Who Work with Sexual Violence Survivors: The Moderating Role of Posttraumatic Growth

    Science.gov (United States)

    Samios, Christina; Rodzik, Amber K.; Abel, Lisa M.

    2012-01-01

    Due to their secondary exposure to the traumatic events disclosed by clients, therapists who work with sexual violence survivors are at risk of experiencing secondary traumatic stress. We examined whether the negative effects of secondary traumatic stress on therapist adjustment would be buffered by posttraumatic growth. Sixty-one therapists who…

  17. Protective or harmful? Exploring the ambivalent role of social identification as a moderator of intergroup stress in sojourners

    NARCIS (Netherlands)

    Bierwiaczonek, Kinga; Waldzus, Sven; van der Zee, Karen

    2017-01-01

    Living outside one's home country may be stressful, and having strong social ties should help deal with this stress. However, social ties may be protective or harmful depending on whether the social group they evoke belongs to the host- or the home country context. The current study examines how

  18. Relational Security Moderates the Effect of Serotonin Transporter Gene Polymorphism (5-HTTLPR) on Stress Generation and Depression among Adolescents

    Science.gov (United States)

    Starr, Lisa R.; Hammen, Constance; Brennan, Patricia A.; Najman, Jake M.

    2013-01-01

    Previous research demonstrates that carriers of the short allele of the serotonin transporter gene (5-HTTLPR) show both greater susceptibility to depression in response to stressful life events and higher rates of generation of stressful events in response to depression. The current study examines relational security (i.e., self-reported beliefs…

  19. Soil Compressibility Models for a Wide Stress Range

    KAUST Repository

    Chong, Song-Hun; Santamarina, Carlos

    2016-01-01

    Soil compressibility models with physically correct asymptotic void ratios are required to analyze situations that involve a wide stress range. Previously suggested models and other functions are adapted to satisfy asymptotic void ratios at low

  20. The impact of self-efficacy, alexithymia and multiple traumas on posttraumatic stress disorder and psychiatric co-morbidity following epileptic seizures: a moderated mediation analysis.

    Science.gov (United States)

    Chung, Man Cheung; Allen, Rachel D; Dennis, Ian

    2013-12-30

    This study investigated the incidence of posttraumatic stress disorder (PTSD) and psychiatric co-morbidity following epileptic seizure, whether alexithymia mediated the relationship between self-efficacy and psychiatric outcomes, and whether the mediational effect was moderated by the severity of PTSD from other traumas. Seventy-one (M=31, F=40) people with a diagnosis of epilepsy recruited from support groups in the United Kingdom completed the Posttraumatic Stress Diagnostic Scale, the Hospital Anxiety and Depression Scale, the Toronto Alexithymia Scale-20 and the Generalized Self-Efficacy Scale. They were compared with 71 people (M=29, F=42) without epilepsy. For people with epilepsy, 51% and 22% met the diagnostic criteria for post-epileptic seizure PTSD and for PTSD following one other traumatic life event respectively. For the control group, 24% met the diagnostic criteria for PTSD following other traumatic life events. The epilepsy group reported significantly more anxiety and depression than the control. Partial least squares (PLS) analysis showed that self-efficacy was significantly correlated with alexithymia, post-epileptic seizure PTSD and psychiatric co-morbidity. Alexithymia was also significantly correlated with post-epileptic seizure PTSD and psychiatric co-morbidity. Mediation analyses confirmed that alexithymia mediated the path between self-efficacy and post-epileptic seizure PTSD and psychiatric co-morbidity. Moderated mediation also confirmed that self-efficacy and PTSD from one other trauma moderated the effect of alexithymia on outcomes. To conclude, people can develop posttraumatic stress disorder symptoms and psychiatric co-morbidity following epileptic seizure. These psychiatric outcomes are closely linked with their belief in personal competence to deal with stressful situations and regulate their own functioning, to process rather than defend against distressing emotions, and with the degree of PTSD from other traumas. © 2013 Elsevier

  1. Regular moderate or intense exercise prevents depression-like behavior without change of hippocampal tryptophan content in chronically tryptophan-deficient and stressed mice.

    Directory of Open Access Journals (Sweden)

    Hosung Lee

    Full Text Available Regular exercise has an antidepressant effect in human subjects. Studies using animals have suggested that the antidepressant effect of exercise is attributable to an increase of brain 5-hydroxytryptamine (5-HT; however, the precise mechanism underlying the antidepressant action via exercise is unclear. In contrast, the effect of 5-HT on antidepressant activity has not been clarified, in part because the therapeutic response to antidepressant drugs has a time lag in spite of the rapid increase of brain 5-HT upon administration of these drugs. This study was designed to investigate the contribution of brain 5-HT to the antidepressant effect of exercise. Mice were fed a tryptophan-deficient diet and stressed using chronic unpredictable stress (CUS for 4 weeks with or without the performance of either moderate or intense exercise on a treadmill 3 days per week. The findings demonstrated that the onset of depression-like behavior is attributable not to chronic reduction of 5-HT but to chronic stress. Regular exercise, whether moderate or intense, prevents depression-like behavior with an improvement of adult hippocampal cell proliferation and survival and without the recovery of 5-HT. Concomitantly, the mice that exercised showed increased hippocampal noradrenaline. Regular exercise prevents the impairment of not long-term memory but short-term memory in a 5-HT-reduced state. Together, these findings suggest that: (1 chronic reduction of brain 5-HT may not contribute to the onset of depression-like behavior; (2 regular exercise, whether moderate or intense, prevents the onset of chronic stress-induced depression-like behavior independent of brain 5-HT and dependent on brain adrenaline; and (3 regular exercise prevents chronic tryptophan reduction-induced impairment of not long-term but short-term memory.

  2. Combat exposure severity as a moderator of genetic and environmental liability to post-traumatic stress disorder.

    Science.gov (United States)

    Wolf, E J; Mitchell, K S; Koenen, K C; Miller, M W

    2014-05-01

    Twin studies of veterans and adults suggest that approximately 30-46% of the variance in post-traumatic stress disorder (PTSD) is attributable to genetic factors. The remaining variance is attributable to the non-shared environment, which, by definition, includes combat exposure. This study used a gene by measured environment twin design to determine whether the effects of genetic and environmental factors that contribute to the etiology of PTSD are dependent on the level of combat exposure. The sample was drawn from the Vietnam Era Twin Registry (VETR) and included 620 male-male twin pairs who served in the US Military in South East Asia during the Vietnam War era. Analyses were based on data from a clinical diagnostic interview of lifetime PTSD symptoms and a self-report measure of combat exposure. Biometric modeling revealed that the effects of genetic and non-shared environment factors on PTSD varied as a function of level of combat exposure such that the association between these factors and PTSD was stronger at higher levels of combat exposure. Combat exposure may act as a catalyst that augments the impact of hereditary and environmental contributions to PTSD. Individuals with the greatest exposure to combat trauma were at increased risk for PTSD as a function of both genetic and environmental factors. Additional work is needed to determine the biological and environmental mechanisms driving these associations.

  3. Testing Moderating Effects in PLS Path Models: An Illustration of Available Procedures

    NARCIS (Netherlands)

    Fassott, Georg; Vinzi, Vincenzo Esposito; Chin, Wynne W.; Henseler, Jörg; Wang, Huiwen

    2010-01-01

    Along with the development of scientific disciplines, namely social sciences, hypothesized relationships become increasingly more complex. Besides the examination of direct effects, researchers are more and more interested in moderating effects. Moderating effects are evoked by variables whose

  4. The moderator's moderator

    International Nuclear Information System (INIS)

    Williamson, G.K.

    1990-01-01

    A brief account is given of the development of graphite moderators for Magnox and advanced gas cooled reactors. The accident at Windscale in 1957 brought to worldwide attention the importance of irradiation damage in graphite and the consequent storage of Wigner energy. In spite of the Windscale setback, preparations for the civil programme of Magnox reactors went ahead apace. Some of the background to the disastrous Dungeness B tender is presented. In spite of all the difficulties and uncertainties, the graphite in UK reactors has performed well. In all cases, as far as the author is aware, the behaviour of the graphite moderators will not prevent design life being achieved. (author)

  5. Post-traumatic stress disorder and beyond: an overview of rodent stress models.

    Science.gov (United States)

    Schöner, Johanna; Heinz, Andreas; Endres, Matthias; Gertz, Karen; Kronenberg, Golo

    2017-10-01

    Post-traumatic stress disorder (PTSD) is a psychiatric disorder of high prevalence and major socioeconomic impact. Patients suffering from PTSD typically present intrusion and avoidance symptoms and alterations in arousal, mood and cognition that last for more than 1 month. Animal models are an indispensable tool to investigate underlying pathophysiological pathways and, in particular, the complex interplay of neuroendocrine, genetic and environmental factors that may be responsible for PTSD induction. Since the 1960s, numerous stress paradigms in rodents have been developed, based largely on Seligman's seminal formulation of 'learned helplessness' in canines. Rodent stress models make use of physiological or psychological stressors such as foot shock, underwater trauma, social defeat, early life stress or predator-based stress. Apart from the brief exposure to an acute stressor, chronic stress models combining a succession of different stressors for a period of several weeks have also been developed. Chronic stress models in rats and mice may elicit characteristic PTSD-like symptoms alongside, more broadly, depressive-like behaviours. In this review, the major existing rodent models of PTSD are reviewed in terms of validity, advantages and limitations; moreover, significant results and implications for future research-such as the role of FKBP5, a mediator of the glucocorticoid stress response and promising target for therapeutic interventions-are discussed. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  6. The moderating role of psychological capital in the relationship between job stress and the outcomes of incivility and job involvement amongst call centre employees

    Directory of Open Access Journals (Sweden)

    Sarah B. Setar

    2015-12-01

    Full Text Available Orientation: South African call centres were found to rank amongst those with the highest degree of performance monitoring and feedback. This revelation comes at a time when many scholars concur that research has not entirely succeeded in helping organisations overcome the negative aspects of work and enhance the positive aspects of work, such as job involvement. Research purpose: This study sought to examine the relationship between job stress, job involvement and the display of uncivil behaviour amongst call centre employees, whilst also studying the role of psychological capital (PsyCap in this relationship. Motivation for the study: The study was prompted by the scarcity of research in the area of PsyCap and job involvement, none of which has examined relationships between job stress and the outcomes of incivility and job involvement and the moderating role of PsyCap in this relationship, focusing on call centre employees. Research design, approach and method: A quantitative design employed a cross-sectional survey to collect data from 104 South African call centre employees using a biographical data sheet, the PsyCap Questionnaire, Job Stress Scale, Uncivil Workplace Behaviour Scale and the Job Involvement Scale. Main findings: PsyCap and uncivil workplace behaviour were negatively related, whilst PsyCap and job involvement were positively related. Job stress held predictive value for incivility and the hostility subscale. Hierarchical regression analysis indicated that PsyCap did not moderate the relationship between job stress and incivility and neither did it moderate the relationship between job stress and job involvement. Practical implications: Organisations should work on minimising stressors within the workplace in order to enhance the PsyCap of employees, which not only lowers the risk of incivility displayed by employees but also ensures greater employee involvement. Contribution/value-add: Although previous studies have examined

  7. Maltreatment, Coping, and Substance Use in Youth in Foster Care: Examination of Moderation Models.

    Science.gov (United States)

    Gabrielli, Joy; Jackson, Yo; Huffhines, Lindsay; Stone, Katie

    2018-05-01

    Child maltreatment is associated with negative outcomes such as substance use (SU). This study tested relations among maltreatment history, coping behavior, and SU behavior in youth residing in foster care. Participants were 210 youth ( M age = 12.71 years; SD = 2.95) in foster care who completed self-report measures through an audio computer-assisted self-interview program. Using a structural equation modeling framework and latent measurement constructs, positive associations were identified between maltreatment at baseline and coping behavior outcomes as well as SU behavior outcome approximately 4.5 months later. Specifically, greater severity and chronicity of maltreatment was associated with greater SU behavior as well as indirect action, prosocial, and asocial coping behavior. Maltreatment was not significantly related to direct action coping behavior. In moderation tests, only asocial coping provided a significant interaction effect for SU behavior outcomes; SU behavior did not moderate pathways between maltreatment and coping behavior. For youth in foster care, the coping approach may be varied and relate differentially to SU behavior outcomes, with asocial approaches to coping acting as a buffer for the maltreatment/SU relation. Additionally, SU remains an important target for intervention and prevention in youth residing in foster care.

  8. Concrete creep and thermal stresses:new creep models and their effects on stress development

    OpenAIRE

    Westman, Gustaf

    1999-01-01

    This thesis deals with the problem of creep in concrete and its influence on thermal stress development. New test frames were developed for creep of high performance concrete and for measurements of thermal stress development. Tests were performed on both normal strength and high performance concretes. Two new models for concrete creep are proposed. Firstly, a viscoelastic model, the triple power law, is supplemented with two additional functions for an improved modelling of the early age cre...

  9. Subjective age and perceived distance-to-death moderate the association between posttraumatic stress symptoms and posttraumatic growth among older adults.

    Science.gov (United States)

    Palgi, Yuval

    2016-09-01

    Little research has addressed the association between posttraumatic stress (PTS) symptoms and posttraumatic growth (PTG) in the second half of life. This study examined whether subjective age and perceived distance-to-death moderate this association. 339 community-dwelling older adults (age range 50-90; M = 65.44, SD = 9.77) were sampled through random dialing to Jewish residents in the south of Israel. Participants completed a phone-questionnaire on PTS symptoms, level of PTG, subjective age, and perceived distance-to-death. Higher levels of PTS symptoms were both linearly and curvilinearly related to higher PTG. Additionally, subjective age and perceived distance-to-death moderated this association in a linear way, so that the association was strongest in participants who reported younger subjective age and further distance-to-death. The findings emphasize the moderating effect of two time perspectives, one that focuses on time since birth and another that concerns the time that remains before death. These two perspectives affect the association between posttraumatic stress and posttraumatic growth within older individuals.

  10. The five-factor model of personality, work stress and professional quality of life in neonatal intensive care unit nurses.

    Science.gov (United States)

    Barr, Peter

    2018-06-01

    The study aim was to determine the direct and indirect relations of the five-factor model of personality traits and work stress with professional quality of life in neonatal nurses. Neonatal intensive care nursing has positive and negative effects on neonatal nurses' psychological well-being. Although individual and situational factors interact to influence professional quality of life, there have been few studies of these relationships in neonatal nurses. A cross-sectional study conducted in 2016. Self-report questionnaires were used to measure professional quality of life (burnout, secondary traumatic stress and compassion satisfaction), five-factor model of personality traits (neuroticism, agreeableness, extraversion, conscientiousness and openness) and work stress (role ambiguity, role conflict and role overload). One hundred and forty (34%) of 405 eligible neonatal nurses provided the data. After controlling for work stress, neuroticism and agreeableness were related to burnout, neuroticism was related to secondary traumatic stress, and extraversion was related to compassion satisfaction. Work stress controlled for personality traits was related to burnout and secondary traumatic stress, but not to compassion satisfaction. Neuroticism moderated the effect of work stress on secondary traumatic stress and agreeableness and openness moderated the effect of work stress on compassion satisfaction. Work stress mediated the effect of neuroticism and extraversion on burnout and the effects of extraversion and conscientiousness on compassion satisfaction. Strategies to reduce work stress may not lessen burnout and secondary traumatic stress or increase compassion satisfaction in neonatal nurses who are prone to high neuroticism, low agreeableness and low extraversion. © 2018 John Wiley & Sons Ltd.

  11. Family incivility and job performance: a moderated mediation model of psychological distress and core self-evaluation.

    Science.gov (United States)

    Lim, Sandy; Tai, Kenneth

    2014-03-01

    This study extends the stress literature by exploring the relationship between family incivility and job performance. We examine whether psychological distress mediates the link between family incivility and job performance. We also investigate how core self-evaluation might moderate this mediated relationship. Data from a 2-wave study indicate that psychological distress mediates the relationship between family incivility and job performance. In addition, core self-evaluation moderates the relationship between family incivility and psychological distress but not the relationship between psychological distress and job performance. The results hold while controlling for general job stress, family-to-work conflict, and work-to-family conflict. The findings suggest that family incivility is linked to poor performance at work, and psychological distress and core self-evaluation are key mechanisms in the relationship.

  12. Models of alien species richness show moderate predictive accuracy and poor transferability

    Directory of Open Access Journals (Sweden)

    César Capinha

    2018-06-01

    Full Text Available Robust predictions of alien species richness are useful to assess global biodiversity change. Nevertheless, the capacity to predict spatial patterns of alien species richness remains largely unassessed. Using 22 data sets of alien species richness from diverse taxonomic groups and covering various parts of the world, we evaluated whether different statistical models were able to provide useful predictions of absolute and relative alien species richness, as a function of explanatory variables representing geographical, environmental and socio-economic factors. Five state-of-the-art count data modelling techniques were used and compared: Poisson and negative binomial generalised linear models (GLMs, multivariate adaptive regression splines (MARS, random forests (RF and boosted regression trees (BRT. We found that predictions of absolute alien species richness had a low to moderate accuracy in the region where the models were developed and a consistently poor accuracy in new regions. Predictions of relative richness performed in a superior manner in both geographical settings, but still were not good. Flexible tree ensembles-type techniques (RF and BRT were shown to be significantly better in modelling alien species richness than parametric linear models (such as GLM, despite the latter being more commonly applied for this purpose. Importantly, the poor spatial transferability of models also warrants caution in assuming the generality of the relationships they identify, e.g. by applying projections under future scenario conditions. Ultimately, our results strongly suggest that predictability of spatial variation in richness of alien species richness is limited. The somewhat more robust ability to rank regions according to the number of aliens they have (i.e. relative richness, suggests that models of aliens species richness may be useful for prioritising and comparing regions, but not for predicting exact species numbers.

  13. A proposed residual stress model for oblique turning

    International Nuclear Information System (INIS)

    Elkhabeery, M. M.

    2001-01-01

    A proposed mathematical model is presented for predicting the residual stresses caused by turning. Effects of change in tool free length, cutting speed, feed rate, and the tensile strength of work piece material on the maximum residual stress are investigated. The residual stress distribution in the surface region due to turning under unlubricated condition is determined using a deflection etching technique. To reduce the number of experiments required and build the mathematical model for these variables, Response Surface Methodology (RSM) is used. In addition, variance analysis and an experimental check are conducted to determine the prominent parameters and the adequacy of the model. The results show that the tensile stress of the work piece material, cutting speed, and feed rate have significant effects on the maximum residual stresses. The proposed model, that offering good correlation between the experimental and predicted results, is useful in selecting suitable cutting parameters for the machining of different materials. (author)

  14. A plastic damage model with stress triaxiality-dependent hardening

    International Nuclear Information System (INIS)

    Shen Xinpu; Shen Guoxiao; Zhou Lin

    2005-01-01

    Emphases of this study were placed on the modelling of plastic damage behaviour of prestressed structural concrete, with special attention being paid to the stress-triaxiality dependent plastic hardening law and the corresponding damage evolution law. A definition of stress triaxiality was proposed and introduced in the model presented here. Drucker-Prager -type plasticity was adopted in the formulation of the plastic damage constitutive equations. Numerical validations were performed for the proposed plasticity-based damage model with a driver subroutine developed in this study. The predicted stress-strain behaviour seems reasonably accurate for the uniaxial tension and uniaxial compression compared with the experimental data reported in references. Numerical calculations of compressions under various hydrostatic stress confinements were carried out in order to validate the stress triaxiality dependent properties of the model. (authors)

  15. Exploring the relationship between posttraumatic stress disorder and deliberate self-harm: the moderating roles of borderline and avoidant personality disorders.

    Science.gov (United States)

    Gratz, Kim L; Tull, Matthew T

    2012-08-30

    Despite increasing evidence for an association between posttraumatic stress disorder (PTSD) and deliberate self-harm (DSH), few studies have examined the factors that moderate this association or the impact of co-occurring personality disorders among individuals with PTSD on DSH frequency. Given the high rates of co-occurrence between PTSD and two personality disorders of particular relevance to DSH, borderline personality disorder (BPD) and avoidant personality disorder (AVPD), this study examined the moderating role of these personality disorders in the association between PTSD and DSH frequency among a sample of substance use disorder patients (N=61). Patients completed structured clinical interviews assessing PTSD, BPD, and AVPD and a questionnaire assessing DSH. Results revealed more frequent DSH among patients with (vs. without) PTSD and provided evidence for the moderating role of AVPD in this association. Specifically, results revealed heightened levels of DSH only among PTSD patients with co-occurring AVPD. Findings are consistent with past research demonstrating that the presence of co-occurring AVPD among patients with other Axis I and II disorders is associated with worse outcomes, and highlight the importance of continuing to examine the moderating role of AVPD in the association between PTSD and a variety of health-risk behaviors. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. The Dark Side of Resilience and Burnout: A Moderation-Mediation Model.

    Directory of Open Access Journals (Sweden)

    Luke Treglown

    Full Text Available This study tested whether specific dark-side traits may be beneficial in manifesting and maintaining Resilience, whilst others are vulnerability factors for Burnout. Four hundred and fifty-one (50 female ambulance personnel completed three questionnaires as a part of a selection and development assessment. The study utilised the Hogan Development survey as a measure of dark side personality, the Copenhagen Burnout Inventory to assess work-related burnout, and the Resilience Scale- 14 to measure resilience levels. Those high on Excitable and Cautious but low on Bold and Reserved were linked to an increased vulnerability to Burnout. Also those high on Bold and Diligent yet low on the Excitable, Cautious, and Imaginative scales were more resilient. Structural Equation Modelling revealed that resilience plays both a mediating and moderating role on personality and burnout. Theoretical implications suggest future research assessing the predictive capacity of psychological variables on burnout should account the indirect effect of resilience.

  17. The Dark Side of Resilience and Burnout: A Moderation-Mediation Model.

    Science.gov (United States)

    Treglown, Luke; Palaiou, Kat; Zarola, Anthony; Furnham, Adrian

    2016-01-01

    This study tested whether specific dark-side traits may be beneficial in manifesting and maintaining Resilience, whilst others are vulnerability factors for Burnout. Four hundred and fifty-one (50 female) ambulance personnel completed three questionnaires as a part of a selection and development assessment. The study utilised the Hogan Development survey as a measure of dark side personality, the Copenhagen Burnout Inventory to assess work-related burnout, and the Resilience Scale- 14 to measure resilience levels. Those high on Excitable and Cautious but low on Bold and Reserved were linked to an increased vulnerability to Burnout. Also those high on Bold and Diligent yet low on the Excitable, Cautious, and Imaginative scales were more resilient. Structural Equation Modelling revealed that resilience plays both a mediating and moderating role on personality and burnout. Theoretical implications suggest future research assessing the predictive capacity of psychological variables on burnout should account the indirect effect of resilience.

  18. Linking subordinate political skill to supervisor dependence and reward recommendations: a moderated mediation model.

    Science.gov (United States)

    Shi, Junqi; Johnson, Russell E; Liu, Yihao; Wang, Mo

    2013-03-01

    In this study, we examined the relations of subordinate political skill with supervisor's dependence on the subordinate and supervisor reward recommendation, as well as mediating (interaction frequency with supervisor) and moderating (supervisor political behavior) variables of these relations. Our theoretical model was tested using data collected from employees in a company that specialized in construction management. Analyses of multisource and lagged data from 53 construction management team supervisors and 296 subordinates indicated that subordinate political skill was positively related to supervisor reward recommendation via subordinate's interaction frequency with supervisor. Although interaction frequency with a supervisor was also positively related to the supervisor's dependence on the subordinate, the indirect effect of subordinate political skill on dependence was not significant. Further, both the relationship between subordinate political skill and interaction frequency with a supervisor and the indirect relationships between subordinate political skill and supervisor reward recommendation were stronger when supervisors exhibited more political behavior.

  19. KAJIAN PENGARUH MODERATING KELOMPOK PENGGUNA DALAM PENERIMAAN GSM-WLAN DI KOTA BANDUNG BERDASARKAN MODEL UTAUT

    Directory of Open Access Journals (Sweden)

    Syarif Hidayatulloh

    2016-03-01

    Full Text Available Abstract - The increasing use of the internet is testament to the rapid development of technology. GSM-WLAN is one technology that is manifested by the provider with the aim can hit 3G and 4G technology which requires a very large investment funds for the internet service provider. One of its main objectives is the big cities that became the majority of the largest internet usage in Indonesia, Bandung City region was no exception as the capital of the province and city tours. Therefore please note the acceptance of these technologies in the community. The model that is used to find out the level of acceptance and use of such technology is a Unified Theory of Acceptance and Use of Technology (UTAUT. In this study examined factors that supposedly affects the acceptance and use of technology GSM-WLAN in Bandung. Those factors among other performance expectancy, effort expectancy, social influence, facilitating conditions and price value to account for the contribution of each variable to predict the user's stance on such technology by using user groups as a moderator variable. Data processing method used is a Structural Equation Models (SEM that use software AMOS. The data processing of the obtained results performance expectancy value and price effect on attitudes toward the use of GSM technology-WLAN. While the moderator variable user groups influence on the attitude of the users in using GSM technology WLAN. Keywords: Internet, WLAN, GSM-UTAUT, SEM Abstrak - Penggunaan internet yang semakin meningkatnya merupakan bukti perkembangan teknologi yang sangat pesat. GSM-WLAN merupakan salah satu teknologi yang dihadirkan oleh para provider dengan tujuan dapat menekan penggunaan teknologi 3G dan 4G yang memerlukan innvestasi dana yang sangat besar bagi para penyedia layanan internet. Salah satu sasaran utamanya ialah kota-kota besar yang menjadi mayoritas penggunaan internet terbesar di Indonesia, tidak terkecuali wilayah Kota Bandung sebagai Ibu kota

  20. Continuous Video Modeling to Prompt Completion of Multi-Component Tasks by Adults with Moderate Intellectual Disability

    Science.gov (United States)

    Mechling, Linda C.; Ayres, Kevin M.; Purrazzella, Kaitlin; Purrazzella, Kimberly

    2014-01-01

    This investigation examined the ability of four adults with moderate intellectual disability to complete multi-component tasks using continuous video modeling. Continuous video modeling, which is a newly researched application of video modeling, presents video in a "looping" format which automatically repeats playing of the video while…

  1. Modulation Methods for Three-level Neutral-Point-Clamped Inverter Achieving Stress Redistribution under Moderate Modulation Index

    DEFF Research Database (Denmark)

    Ma, Ke; Blaabjerg, Frede

    2016-01-01

    This letter investigates the loss and thermal behaviors of a three-level neutral-point-clamped (3L-NPC) inverter undergoing moderate modulation index, which is typically presented during minor voltage sags of the power grid or speed changes of the electric machines. A series of new space vector m...

  2. Respiratory sinus arrhythmia as a predictor of eating disorder symptoms in college students: Moderation by responses to stress and parent psychological control.

    Science.gov (United States)

    Abaied, Jamie L; Wagner, Caitlin; Breslend, Nicole Lafko; Flynn, Megan

    2016-04-01

    This longitudinal study examined the prospective contribution of respiratory sinus arrhythmia (RSA), a key physiological indicator of self-regulation, to eating disorder symptoms in college students, and whether this link was moderated by maladaptive responses to stress and parent psychological control. At Wave 1, college students' RSA was measured at rest. At Waves 1 and 2 (six-month follow-up), students reported on their eating disorder symptoms, coping and involuntary responses to stress, and perceptions of their parents' use of psychological control. Significant three-way interactions indicated that the link between RSA and subsequent eating disorder symptoms was contingent on responses to stress and parent psychological control. In the context of maladaptive responses to stress and high psychological control, RSA predicted increased eating disorder symptoms over time. In the absence of parent psychological control, high RSA was beneficial in most cases, even when individuals reported maladaptive responses to stress. This study presents novel evidence that high RSA contributes to risk for or resilience to eating disorder symptoms over time. RSA can be protective against eating disorder symptoms, but in some contexts, the self-regulation resources that high RSA provides may be inappropriately applied to eating cognitions and behaviors. This research highlights the importance of examining physiological functioning conjointly with other risk factors as precursors to eating disorder symptoms over time. Copyright © 2016. Published by Elsevier Ltd.

  3. Moderating effects of coping styles on anxiety and depressive symptoms caused by psychological stress in Chinese patients with Type 2 diabetes.

    Science.gov (United States)

    Zhang, C-X; Tse, L-A; Ye, X-Q; Lin, F-Y; Chen, Y-M; Chen, W-Q

    2009-12-01

    This study aimed to assess possible interactive effects of coping styles and psychological stress on depression and anxiety symptoms in Chinese patients with Type 2 diabetes. Three hundred and four patients with Type 2 diabetes underwent a face-to-face interview by trained research staff according to a standardized questionnaire including information on socio-demographic characteristics, psychological stress, coping styles and anxiety and depressive symptoms. The interactive effects of coping styles and psychological stress on depression and anxiety symptoms were assessed by hierarchical multiple regression analyses. There were significant associations of the four domains of psychological stress with anxiety and depressive symptoms, except for the relationship between 'reduced economic condition' and depressive symptoms. 'Negative coping style' significantly increased the level of both anxiety and depressive symptoms; whereas, 'active coping style' and 'avoidant coping style' decreased the risk of depressive symptoms. The interactions of 'negative coping style' with 'worrying about decline in body/physical function' and 'reduced economic condition' significantly increased the risk of anxiety and depressive symptoms, and the interaction of 'social/family crisis caused by the disease' with 'avoidance coping style' and 'worrying about decline in body/physical function' with 'active coping style' significantly decreased the risk of depressive symptoms. The results of this study suggest that certain coping styles might moderate the association of psychological stress with anxiety and depressive symptoms in Chinese patients with Type 2 diabetes.

  4. Effects of induced stress on seismic forward modelling and inversion

    Science.gov (United States)

    Tromp, Jeroen; Trampert, Jeannot

    2018-05-01

    We demonstrate how effects of induced stress may be incorporated in seismic modelling and inversion. Our approach is motivated by the accommodation of pre-stress in global seismology. Induced stress modifies both the equation of motion and the constitutive relationship. The theory predicts that induced pressure linearly affects the unstressed isotropic moduli with a slope determined by their adiabatic pressure derivatives. The induced deviatoric stress produces anisotropic compressional and shear wave speeds; the latter result in shear wave splitting. For forward modelling purposes, we determine the weak form of the equation of motion under induced stress. In the context of the inverse problem, we determine induced stress sensitivity kernels, which may be used for adjoint tomography. The theory is illustrated by considering 2-D propagation of SH waves and related Fréchet derivatives based on a spectral-element method.

  5. Modeling of CMUTs with Multiple Anisotropic Layers and Residual Stress

    DEFF Research Database (Denmark)

    Engholm, Mathias; Thomsen, Erik Vilain

    2014-01-01

    Usually the analytical approach for modeling CMUTs uses the single layer plate equation to obtain the deflection and does not take anisotropy and residual stress into account. A highly accurate model is developed for analytical characterization of CMUTs taking an arbitrary number of layers...... and residual stress into account. Based on the stress-strain relation of each layer and balancing stress resultants and bending moments, a general multilayered anisotropic plate equation is developed for plates with an arbitrary number of layers. The exact deflection profile is calculated for a circular...... clamped plate of anisotropic materials with residual bi-axial stress. From the deflection shape the critical stress for buckling is calculated and by using the Rayleigh-Ritz method the natural frequency is estimated....

  6. Cardiovascular Benefits of Moderate Exercise Training in Marfan Syndrome: Insights From an Animal Model.

    Science.gov (United States)

    Mas-Stachurska, Aleksandra; Siegert, Anna-Maria; Batlle, Monsterrat; Gorbenko Del Blanco, Darya; Meirelles, Thayna; Rubies, Cira; Bonorino, Fabio; Serra-Peinado, Carla; Bijnens, Bart; Baudin, Julio; Sitges, Marta; Mont, Lluís; Guasch, Eduard; Egea, Gustavo

    2017-09-25

    Marfan syndrome (MF) leads to aortic root dilatation and a predisposition to aortic dissection, mitral valve prolapse, and primary and secondary cardiomyopathy. Overall, regular physical exercise is recommended for a healthy lifestyle, but dynamic sports are strongly discouraged in MF patients. Nonetheless, evidence supporting this recommendation is lacking. Therefore, we studied the role of long-term dynamic exercise of moderate intensity on the MF cardiovascular phenotype. In a transgenic mouse model of MF ( Fbn1 C1039G/+ ), 4-month-old wild-type and MF mice were subjected to training on a treadmill for 5 months; sedentary littermates served as controls for each group. Aortic and cardiac remodeling was assessed by echocardiography and histology. The 4-month-old MF mice showed aortic root dilatation, elastic lamina rupture, and tunica media fibrosis, as well as cardiac hypertrophy, left ventricular fibrosis, and intramyocardial vessel remodeling. Over the 5-month experimental period, aortic root dilation rate was significantly greater in the sedentary MF group, compared with the wild-type group (∆mm, 0.27±0.07 versus 0.13±0.02, respectively). Exercise significantly blunted the aortic root dilation rate in MF mice compared with sedentary MF littermates (∆mm, 0.10±0.04 versus 0.27±0.07, respectively). However, these 2 groups were indistinguishable by aortic root stiffness, tunica media fibrosis, and elastic lamina ruptures. In MF mice, exercise also produced cardiac hypertrophy regression without changes in left ventricular fibrosis. Our results in a transgenic mouse model of MF indicate that moderate dynamic exercise mitigates the progression of the MF cardiovascular phenotype. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

  7. State dissociation moderates response to dialectical behavior therapy for posttraumatic stress disorder in women with and without borderline personality disorder.

    Science.gov (United States)

    Kleindienst, Nikolaus; Priebe, Kathlen; Görg, Nora; Dyer, Anne; Steil, Regina; Lyssenko, Lisa; Winter, Dorina; Schmahl, Christian; Bohus, Martin

    2016-01-01

    Patients with posttraumatic stress disorder (PTSD) are prone to dissociation, which in theory should interfere with successful treatment. However, most empirical studies do not substantiate this assumption. The primary objective was to test whether state dissociation predicts the success of an adaptation of dialectical behavior therapy designed for the treatment of patients with PTSD after childhood sexual abuse (CSA) (DBT-PTSD). We further explored whether the operationalization of dissociation as state versus trait dissociation made a difference with respect to prediction of improvement. We present a hypothesis-driven post hoc analysis of a randomized controlled trial on the efficacy in patients with PTSD after CSA. Regression analyses relating pre-post improvements in the Clinician-Administered PTSD Scale (CAPS) and the Posttraumatic Diagnostic Scale (PDS) to dissociation were applied to the women who participated in the active treatment arm (DBT-PTSD). Multivariate models accounting for major confounders were used to relate improvements in both the CAPS and the PDS to (1) state dissociation as assessed after each treatment session and (2) trait dissociation as assessed at baseline. State dissociation during psychotherapy sessions predicted improvement after DBT-PTSD: patients with low state dissociation during treatment had a higher chance to show substantial improvement. This relation consistently emerged across subgroups of PTSD patients with and without borderline personality disorder. The operationalization of dissociation as state versus trait dissociation made a difference as improvement was not significantly predicted from trait dissociation. Dissociation during treatment sessions may reduce success with trauma-focused therapies such as DBT-PTSD. Accordingly, clinical studies aimed at improving ways to address dissociation are needed.

  8. State dissociation moderates response to dialectical behavior therapy for posttraumatic stress disorder in women with and without borderline personality disorder

    Directory of Open Access Journals (Sweden)

    Nikolaus Kleindienst

    2016-07-01

    Full Text Available Background: Patients with posttraumatic stress disorder (PTSD are prone to dissociation, which in theory should interfere with successful treatment. However, most empirical studies do not substantiate this assumption. Objective: The primary objective was to test whether state dissociation predicts the success of an adaptation of dialectical behavior therapy designed for the treatment of patients with PTSD after childhood sexual abuse (CSA (DBT-PTSD. We further explored whether the operationalization of dissociation as state versus trait dissociation made a difference with respect to prediction of improvement. Methods: We present a hypothesis-driven post hoc analysis of a randomized controlled trial on the efficacy in patients with PTSD after CSA. Regression analyses relating pre–post improvements in the Clinician-Administered PTSD Scale (CAPS and the Posttraumatic Diagnostic Scale (PDS to dissociation were applied to the women who participated in the active treatment arm (DBT-PTSD. Multivariate models accounting for major confounders were used to relate improvements in both the CAPS and the PDS to (1 state dissociation as assessed after each treatment session and (2 trait dissociation as assessed at baseline. Results: State dissociation during psychotherapy sessions predicted improvement after DBT-PTSD: patients with low state dissociation during treatment had a higher chance to show substantial improvement. This relation consistently emerged across subgroups of PTSD patients with and without borderline personality disorder. The operationalization of dissociation as state versus trait dissociation made a difference as improvement was not significantly predicted from trait dissociation. Conclusions: Dissociation during treatment sessions may reduce success with trauma-focused therapies such as DBT-PTSD. Accordingly, clinical studies aimed at improving ways to address dissociation are needed.

  9. New model for surface fracture induced by dynamical stress

    OpenAIRE

    Andersen, J. V.; Lewis, L. J.

    1997-01-01

    We introduce a model where an isotropic, dynamically-imposed stress induces fracture in a thin film. Using molecular dynamics simulations, we study how the integrated fragment distribution function depends on the rate of change and magnitude of the imposed stress, as well as on temperature. A mean-field argument shows that the system becomes unstable for a critical value of the stress. We find a striking invariance of the distribution of fragments for fixed ratio of temperature and rate of ch...

  10. Minority stress and relationship functioning among young male same-sex couples: An examination of actor-partner interdependence models.

    Science.gov (United States)

    Feinstein, Brian A; McConnell, Elizabeth; Dyar, Christina; Mustanski, Brian; Newcomb, Michael E

    2018-05-01

    In different-sex couples, individual and partner stress can both have a negative impact on relationship functioning (actor and partner effects). Gay and bisexual men experience unique stress (sexual minority stress), but few studies have examined the effects of this stress on relationship functioning among young male couples. The current study examined (a) actor and partner effects of general and minority stress (internalized stigma, microaggressions, victimization, and outness) on relationship functioning (relationship quality and negative relationship interactions), (b) interactions between individual and partner stress as predictors of relationship functioning, and (c) dyadic coping and relationship length as moderators of actor and partner effects. Actor-partner interdependence models were tested using data from 153 young male couples. There was strong support for actor effects. Higher general stress and internalized stigma were associated with lower relationship quality, but only for those in longer relationships. Additionally, higher general stress, internalized stigma, and microaggressions, and lower outness, were associated with more negative relationship interactions. There was limited support for partner effects. Having a partner with higher internalized stigma was associated with more negative relationship interactions, but none of the other partner effects were significant. There was no support for individual and partner stress interacting to predict relationship functioning or for dyadic coping as a stress buffer. Findings highlight the influence of one's own experiences of general and minority stress on relationship functioning, but raise questions about how partner stress influences relationship functioning among young male couples. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  11. New mesoscopic constitutive model for deformation of pearlitic steels up to moderate strains

    Science.gov (United States)

    Alkorta, J.; Martínez-Esnaola, J. M.; de Jaeger, P.; Gil Sevillano, J.

    2017-07-01

    A new constitutive model for deformation of pearlitic steels has been developed that describes the mechanical behaviour and microstructural evolution of lamellar multi-colony pearlite. The model, a two-phase continuum model, considers the plastic anisotropy of ferrite derived from its lamellar structure but ignores any anisotropy associated with cementite and does not consider the crystal structure of either constituent. The resulting plastic constitutive equation takes into account a dependence on both the pearlitic spacing (arising from the confined slip of dislocations in the lamellae) and on strengthening from the evolving intra-lamellar dislocation density. A Kocks-Mecking strain hardening/recovery model is used for the lamellar ferrite, whereas perfect-plastic behaviour is assumed for cementite. The model naturally captures the microstructural evolution and the internal micro-stresses developed due to the different mechanical behaviour of both phases. The model is also able to describe the lamellar evolution (orientation and interlamellar spacing) with good accuracy. The role of plastic anisotropy in the ferritic phase has also been studied, and the results show that anisotropy has an important impact on both microstructural evolution and strengthening of heavily drawn wires.

  12. A hierarchical stress release model for synthetic seismicity

    Science.gov (United States)

    Bebbington, Mark

    1997-06-01

    We construct a stochastic dynamic model for synthetic seismicity involving stochastic stress input, release, and transfer in an environment of heterogeneous strength and interacting segments. The model is not fault-specific, having a number of adjustable parameters with physical interpretation, namely, stress relaxation, stress transfer, stress dissipation, segment structure, strength, and strength heterogeneity, which affect the seismicity in various ways. Local parameters are chosen to be consistent with large historical events, other parameters to reproduce bulk seismicity statistics for the fault as a whole. The one-dimensional fault is divided into a number of segments, each comprising a varying number of nodes. Stress input occurs at each node in a simple random process, representing the slow buildup due to tectonic plate movements. Events are initiated, subject to a stochastic hazard function, when the stress on a node exceeds the local strength. An event begins with the transfer of excess stress to neighboring nodes, which may in turn transfer their excess stress to the next neighbor. If the event grows to include the entire segment, then most of the stress on the segment is transferred to neighboring segments (or dissipated) in a characteristic event. These large events may themselves spread to other segments. We use the Middle America Trench to demonstrate that this model, using simple stochastic stress input and triggering mechanisms, can produce behavior consistent with the historical record over five units of magnitude. We also investigate the effects of perturbing various parameters in order to show how the model might be tailored to a specific fault structure. The strength of the model lies in this ability to reproduce the behavior of a general linear fault system through the choice of a relatively small number of parameters. It remains to develop a procedure for estimating the internal state of the model from the historical observations in order to

  13. Nurses' intention to resign and avoidance of emergency department violence: A moderated mediation model.

    Science.gov (United States)

    Li, Yu-Fang; Chao, Minston; Shih, Chih-Ting

    2017-10-10

    Studies that examined the negative impact of violence in emergency departments on nurses' leave and avoidance behavior are well-documented. However, few studies provided an integrated model of how and when violence influences their leave and avoidance behavior. The study adopted Affective Events Theory to propose and examine a model of violent events, negative emotions, and (leave and avoidance) behaviors on nurses in emergency departments and further analyzed whether the model is salient to nurses' occupational burnout, nursing experience, and nursing rank. The sample included 123 emergency department nurses at a teaching hospital in northern, Taiwan. All participants had experienced violent incidents within the preceding 6 months. Moderated mediation analysis suggested that nurses experienced one of two emotional processes following violent incidents: "violence-negative feelings toward work-intention to resign" or "violence-negative emotion and physical symptoms-avoidance tendencies." Moreover, nurses with high burnout levels expressed weaker intention to resign after violent incidents, while nurses with more experience and higher rank were less likely to avoid violence after violent incidents. Emergency nurses do not simply elect to escape but may engage in avoidance behavior. This study revealed that how violent incidents affect nurses' resignation or avoidance behaviors depends on how they feel. Occupational burnout and nurses' attributes affected their behavior. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. The applied model of imagery use: Examination of moderation and mediation effects.

    Science.gov (United States)

    Koehn, S; Stavrou, N A M; Young, J A; Morris, T

    2016-08-01

    The applied model of mental imagery use proposed an interaction effect between imagery type and imagery ability. This study had two aims: (a) the examination of imagery ability as a moderating variable between imagery type and dispositional flow, and (b) the testing of alternative mediation models. The sample consisted of 367 athletes from Scotland and Australia, who completed the Sport Imagery Questionnaire, Sport Imagery Ability Questionnaire, and Dispositional Flow Scale-2. Hierarchical regression analysis showed direct effects of imagery use and imagery ability on flow, but no significant interaction. Mediation analysis revealed a significant indirect path, indicating a partially mediated relationship (P = 0.002) between imagery use, imagery ability, and flow. Partial mediation was confirmed when the effect of cognitive imagery use and cognitive imagery ability was tested, and a full mediation model was found between motivational imagery use, motivational imagery ability, and flow. The results are discussed in conjunction with potential future research directions on advancing theory and applications. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. Modeling of plates with multiple anisotropic layers and residual stress

    DEFF Research Database (Denmark)

    Engholm, Mathias; Pedersen, Thomas; Thomsen, Erik Vilain

    2016-01-01

    Usually the analytical approach for modeling of plates uses the single layer plate equation to obtain the deflection and does not take anisotropy and residual stress into account. Based on the stress–strain relation of each layer and balancing stress resultants and bending moments, a general...... multilayered anisotropic plate equation is developed for plates with an arbitrary number of layers. The exact deflection profile is calculated for a circular clamped plate of anisotropic materials with residual bi-axial stress.From the deflection shape the critical stress for buckling is calculated......, and an excellent agreement between the two models is seen with a relative difference of less than 2% for all calculations. The model was also used to extract the cell capacitance, the parasitic capacitance and the residual stress of a pressure sensor composed of a multilayered plate of silicon and silicon oxide...

  16. Induced dyadic stress and food intake: Examination of the moderating roles of body mass index and restraint.

    Science.gov (United States)

    Côté, Marilou; Gagnon-Girouard, Marie-Pierre; Provencher, Véronique; Bégin, Catherine

    2016-12-01

    Restrained eaters and overweight and obese people are prone to increase their food intake during stressful situations. This study examines the impact of a stressful couple discussion on food intake in both spouses, while simultaneously taking into account the effect of BMI and restraint on this association. For 15min, 80 heterosexual couples discussed an aspect that they wanted their partner to change followed by an individual bogus taste test for the purpose of measuring his or her stress-induced food intake. Prior to and after the discussion, subjective mood state was assessed, as well as appetite perceptions, and the mood change before and after the discussion was calculated. Multiple regression analyses with a three-way interaction between mood change, BMI, and restraint were used to predict food intake for both men and women, while controlling for appetite perceptions. Only restrained women with a high BMI ate more when their mood worsened. For men, only appetite perceptions significantly predicted food intake. These results suggest that an induced negative mood in the form of a stressful couple discussion impacts food intake differently for men and women, and that particular attention should be given to the concomitant effect of both restraint and BMI when studying stress-induced eating among women. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. finite element model for predicting residual stresses in shielded

    African Journals Online (AJOL)

    eobe

    This paper investigates the prediction of residual stresses developed ... steel plates through Finite Element Model simulation and experiments. ... The experimental values as measured by the X-Ray diffractometer were of ... Based on this, it can be concluded that Finite Element .... Comparison of Residual Stresses from X.

  18. Adolescents' Deliberate Self-Harm, Interpersonal Stress, and the Moderating Effects of Self-Regulation: A Two-Wave Longitudinal Analysis

    Science.gov (United States)

    Jutengren, Goran; Kerr, Margaret; Stattin, Hakan

    2011-01-01

    The predictive effects of peer victimization and harsh parenting on deliberate self-harm were examined. As derived from the experiential avoidance model, the study also tested whether these links were moderated by individual self-regulation approaches. Data were collected at two points in time from 880 junior high school students (mean age =…

  19. Corporate Social Responsibility and Employee Outcomes: A Moderated Mediation Model of Organizational Identification and Moral Identity.

    Science.gov (United States)

    Wang, Wei; Fu, Ying; Qiu, Huiqing; Moore, James H; Wang, Zhongming

    2017-01-01

    Corporate social responsibility (CSR) research is not new, but its importance to today's socially conscious market environment is even more evident in recent years. This study moves beyond CSR as simply the socially responsible actions and policies of organizations and focuses on the complex psychology of CSR as it relates to individuals within the organization. Given CSR can positively affect both the individuals within the organization and the organization itself, better understanding and leveraging the mechanisms and conditions of CSR that facilitate desired employee outcomes is crucial for organizational performance. However, scholars lack consensus in determining a theoretical framework for understanding how and under what conditions CSR will make an impact on employees and ultimately organizational performance. This study adds clarity by exploring the effect of perceived CSR on a more comprehensive set of employees' attitudinal and behavioral reactions (i.e., turnover intention, in-role job performance, and helping behavior) via the mediating mechanism of organizational identification and the moderating condition of moral identity. Hypotheses were derived using social identity theory. Results were based on data obtained from 340 Chinese manufacturing employee-supervisor dyads. This study found that employees' perceived CSR had an indirect relationship via organizational identification with each of the variables: (1) turnover intention, (2) in-role job performance, and (3) helping behavior. Specifically, the negative relationship between perceived CSR and turnover intention was stronger when employees had higher moral identity and the positive relationship between perceived CSR and in-role job performance and helping behavior was amplified by moral identity. Our findings show how the mediating mechanism of organizational identity and the moderating condition of moral identity work together to improve organizational effectiveness. The findings reveal several

  20. Corporate Social Responsibility and Employee Outcomes: A Moderated Mediation Model of Organizational Identification and Moral Identity

    Directory of Open Access Journals (Sweden)

    Wei Wang

    2017-11-01

    Full Text Available Corporate social responsibility (CSR research is not new, but its importance to today’s socially conscious market environment is even more evident in recent years. This study moves beyond CSR as simply the socially responsible actions and policies of organizations and focuses on the complex psychology of CSR as it relates to individuals within the organization. Given CSR can positively affect both the individuals within the organization and the organization itself, better understanding and leveraging the mechanisms and conditions of CSR that facilitate desired employee outcomes is crucial for organizational performance. However, scholars lack consensus in determining a theoretical framework for understanding how and under what conditions CSR will make an impact on employees and ultimately organizational performance. This study adds clarity by exploring the effect of perceived CSR on a more comprehensive set of employees’ attitudinal and behavioral reactions (i.e., turnover intention, in-role job performance, and helping behavior via the mediating mechanism of organizational identification and the moderating condition of moral identity. Hypotheses were derived using social identity theory. Results were based on data obtained from 340 Chinese manufacturing employee-supervisor dyads. This study found that employees’ perceived CSR had an indirect relationship via organizational identification with each of the variables: (1 turnover intention, (2 in-role job performance, and (3 helping behavior. Specifically, the negative relationship between perceived CSR and turnover intention was stronger when employees had higher moral identity and the positive relationship between perceived CSR and in-role job performance and helping behavior was amplified by moral identity. Our findings show how the mediating mechanism of organizational identity and the moderating condition of moral identity work together to improve organizational effectiveness. The

  1. Multimodal assessment of emotional reactivity in borderline personality pathology: the moderating role of posttraumatic stress disorder symptoms.

    Science.gov (United States)

    Dixon-Gordon, Katherine L; Gratz, Kim L; Tull, Matthew T

    2013-08-01

    Emotional reactivity has been theorized to play a central role in borderline personality (BP) pathology. Although growing research provides evidence for subjective emotional reactivity in BP pathology, research on physiological or biological reactivity among people with BP pathology is less conclusive. With regard to biological reactivity in particular, research on cortisol reactivity (a neurobiological marker of emotional reactivity) in response to stressors among individuals with BP pathology has produced contradictory results and highlighted the potential moderating role of PTSD-related pathology. Thus, this study sought to examine the moderating role of PTSD symptoms in the relation between BP pathology and both subjective (self-report) and biological (cortisol) emotional reactivity to a laboratory stressor. Participants were 171 patients in a residential substance use disorder treatment center. Consistent with hypotheses, results revealed a significant main effect of BP pathology on subjective emotional reactivity to the laboratory stressor. Furthermore, results revealed a significant interaction between BP pathology and PTSD symptoms in the prediction of cortisol reactivity, such that BP pathology was associated with heightened cortisol reactivity only among participants with low levels of PTSD symptoms. Similar findings were obtained when examining the interaction between BP pathology and the reexperiencing and avoidance/numbing symptoms of PTSD specifically. Results highlight the moderating role of PTSD symptoms in the BP-reactivity relation. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. LIMIT STRESS SPLINE MODELS FOR GRP COMPOSITES

    African Journals Online (AJOL)

    ES OBE

    INTRODUCTION. The strength of any material used in any design is very important in order to evaluate the performance index of a particular project. Plastics are polymers that are viscoelastic in nature, show time dependence response to applied stress (Creep), [1]. GRP mechanical properties are therefore affected by creep.

  3. Modelling of thermal stress in vapor generator supports

    International Nuclear Information System (INIS)

    Halpert, S.; Vazquez, L.

    1997-01-01

    To assure safety and availability of a nuclear power plant components or equipment stress analysis are done. When thermal loads are involved it's necessary to know the temperature field of the component or equipment. This paper describes the structural analysis of a steam generator lug with thermal load including the model used for computer simulation and presents the evolution of the temperature profile, the stress intensity and principal stress during start up and shut down of a nuclear power reactor. Temperature field obtained from code calculation show good agreement with the experimental data while stress analysis results are in agreement with a preview estimation. (author) [es

  4. Occupational status moderates the association between current perceived stress and high blood pressure: evidence from the IPC cohort study

    Science.gov (United States)

    Wiernik, Emmanuel; Pannier, Bruno; Czernichow, Sébastien; Nabi, Hermann; Hanon, Olivier; Simon, Tabassome; Simon, Jean-Marc; Thomas, Frédérique; Bean, Kathy; Consoli, Silla; Danchin, Nicolas; Lemogne, Cédric

    2013-01-01

    Although lay beliefs commonly relate high blood pressure to psychological stress exposure, research findings are conflicting. This study examined the association between current perceived stress and high blood pressure and explored the potential impact of occupational status on this association. Resting blood pressure was measured in 122,816 adults (84,994 men), aged ≥30 years (mean age ± standard deviation: 46.8±9.9 years), without history of cardiovascular and renal disease and not on either psychotropic or antihypertensive drugs. High blood pressure was defined as systolic blood pressure ≥140 mmHg or diastolic blood pressure ≥90 mmHg. Perceived stress in the past month was measured with the 4-item perceived stress scale. A total of 33,154 participants (27.0%) had high blood pressure (151±14/90±9 mmHg). After adjustment for all variables except occupational status, perceived stress was associated with high blood pressure (odds ratio for a 5-point increase: 1.06, 95% confidence interval: [1.03–1.09]). This association was no longer significant after additional adjustment for occupational status (odds ratio: 1.01 [0.99–1.04]). There was a significant interaction (phigh blood pressure among individuals of high occupational status (odds ratio: 0.91, [0.87–0.96]) but positively associated among those of low status (odds ratio: 1.10, [1.03–1.17]) or unemployed (odds ratio: 1.13, [1.03–1.24]). Sensitivity analyses yielded similar results. The association between current perceived stress and blood pressure depends upon occupational status. This interaction may account for previous conflicting results and warrants further studies to explore its underlying mechanisms. PMID:23319539

  5. Emotional Stress and Cardiovascular Complications in Animal Models: A Review of the Influence of Stress Type.

    Science.gov (United States)

    Crestani, Carlos C

    2016-01-01

    Emotional stress has been recognized as a modifiable risk factor for cardiovascular diseases. The impact of stress on physiological and psychological processes is determined by characteristics of the stress stimulus. For example, distinct responses are induced by acute vs. chronic aversive stimuli. Additionally, the magnitude of stress responses has been reported to be inversely related to the degree of predictability of the aversive stimulus. Therefore, the purpose of the present review was to discuss experimental research in animal models describing the influence of stressor stimulus characteristics, such as chronicity and predictability, in cardiovascular dysfunctions induced by emotional stress. Regarding chronicity, the importance of cardiovascular and autonomic adjustments during acute stress sessions and cardiovascular consequences of frequent stress response activation during repeated exposure to aversive threats (i.e., chronic stress) is discussed. Evidence of the cardiovascular and autonomic changes induced by chronic stressors involving daily exposure to the same stressor (predictable) vs. different stressors (unpredictable) is reviewed and discussed in terms of the impact of predictability in cardiovascular dysfunctions induced by stress.

  6. Stress and Sleep Reactivity: A Prospective Investigation of the Stress-Diathesis Model of Insomnia

    Science.gov (United States)

    Drake, Christopher L.; Pillai, Vivek; Roth, Thomas

    2014-01-01

    Study Objectives: To prospectively assess sleep reactivity as a diathesis of insomnia, and to delineate the interaction between this diathesis and naturalistic stress in the development of insomnia among normal sleepers. Design: Longitudinal. Setting: Community-based. Participants: 2,316 adults from the Evolution of Pathways to Insomnia Cohort (EPIC) with no history of insomnia or depression (46.8 ± 13.2 y; 60% female). Interventions: None. Measurements and Results: Participants reported the number of stressful events they encountered at baseline (Time 1), as well as the level of cognitive intrusion they experienced in response to each stressor. Stressful events (OR = 1.13; P insomnia one year hence (Time 2). Intrusion mediated the effects of stressful events on risk for insomnia (P insomnia (OR = 1.78; P insomnia as a function of intrusion was significantly higher in individuals with high sleep reactivity. Trait sleep reactivity also constituted a significant risk for depression (OR = 1.67; P Insomnia at Time 2 significantly mediated this effect (P insomnia, and that it triggers insomnia by exacerbating the effects of stress-induced intrusion. Sleep reactivity is also a precipitant of depression, as mediated by insomnia. These findings support the stress-diathesis model of insomnia, while highlighting sleep reactivity as an important diathesis. Citation: Drake CL, Pillai V, Roth T. Stress and sleep reactivity: a prospective investigation of the stress-diathesis model of insomnia. SLEEP 2014;37(8):1295-1304. PMID:25083009

  7. Tocopherol And Tocotrienol: Therapeutic Potential In Animal Models of Stress.

    Science.gov (United States)

    Azlina, Mohd Fahami Nur; Kamisah, Yusof; Qodriyah, Mohd Saad

    2017-11-22

    Scientific reports had shown that stress is related to numerous pathological changes in the body. These pathological changes can bring about numerous diseases and can significantly cause negative effects in an individual. These include gastric ulcer, liver pathology and neurobehavioral changes. A common pathogenesis in many diseases related to stress involves oxidative damage. Therefore, the administration of antioxidants such as vitamin E is a reasonable therapeutic approach. However, there is conflicting evidence about antioxidant supplementation. The aim of this work was to summarize documented reports on the effects of tocopherol and tocotrienol on various pathological changes induced by stress. This review will reveal the scientific evidence of enteral supplementation of vitamin E in the forms of tocotrienol and tocopherol in animal models of stress. These models mimic the stress endured by critically ill patients in a clinical setting and psychological stress in individuals. Positive outcomes from enteral feeding of vitamin E in reducing the occurrence of stress-induced pathological changes are discussed in this review. These positive findings include their ability to reduced stress-induced gastric ulcers, elevated liver enzymes and improved locomotors activity. Evidences showing tocotrienol and tocopherol effects are not just related to its ability to reduce oxidative stress but also acting on other mechanism are discussed. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  8. System design and as-built MCNP model comparison for the Lujan Center target moderator reflector system

    International Nuclear Information System (INIS)

    Muhrer, G.; Ferguson, P.D.; Russell, G.J.; Pitcher, E.J.

    2000-01-01

    During the design of the Manuel Lujan, Jr., Neutron Scattering Center target, a simplified Monte Carlo model was used to estimate target system performance and to aid engineers as decisions were made regarding the construction of the target system. Although the simplified model ideally would perfectly reflect the as-built system performance, assumptions were made in the model during the design process that may result in deviations between the model predictions and the as-built system performance. Now that the Lujan Center target system has been completed, a more detailed, as-built, model of the target system has been completed. The purpose of this work is to investigate differences between the predicted target system performance of the simplified model and the as-built model from the standpoint of time-averaged moderator brightness. Calculated discrepancies between the two models have been isolated to a few key issues. Figure 1 shows MCNP geometric plots of the simplified and as-built models. Major differences between these two models include details in the moderator designs (plena) and piping, full versus partial moderator canisters (only in the direction of the extracted neutron beam for the simplified model), and reflector details including cooling pipes and engineering tolerance gaps. In addition, Fig. 1 demonstrates that the detailed model includes shielding and additional material beyond that which was modeled by the original simplified model

  9. Stress field modelling from digital geological map data

    Science.gov (United States)

    Albert, Gáspár; Barancsuk, Ádám; Szentpéteri, Krisztián

    2016-04-01

    To create a model for the lithospheric stress a functional geodatabase is required which contains spatial and geodynamic parameters. A digital structural-geological map is a geodatabase, which usually contains enough attributes to create a stress field model. Such a model is not accurate enough for engineering-geological purposes because simplifications are always present in a map, but in many cases maps are the only sources for a tectonic analysis. The here presented method is designed for field geologist, who are interested to see the possible realization of the stress field over the area, on which they are working. This study presents an application which can produce a map of 3D stress vectors from a kml-file. The core application logic is implemented on top of a spatially aware relational database management system. This allows rapid and geographically accurate analysis of the imported geological features, taking advantage of standardized spatial algorithms and indexing. After pre-processing the map features in a GIS, according to the Type-Property-Orientation naming system, which was described in a previous study (Albert et al. 2014), the first stage of the algorithm generates an irregularly spaced point cloud by emitting a pattern of points within a user-defined buffer zone around each feature. For each point generated, a component-wise approximation of the tensor field at the point's position is computed, derived from the original feature's geodynamic properties. In a second stage a weighted moving average method calculates the stress vectors in a regular grid. Results can be exported as geospatial data for further analysis or cartographic visualization. Computation of the tensor field's components is based on the implementation of the Mohr diagram of a compressional model, which uses a Coulomb fracture criterion. Using a general assumption that the main principal stress must be greater than the stress from the overburden, the differential stress is

  10. A coupled thermo-hydro-mechanical-damage model for concrete subjected to moderate temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Bary, B.; Carpentier, O. [CEA Saclay, DEN/DPC/SCCME/LECBA, F-91191 Gif Sur Yvette, (France); Ranc, G. [CEA VALRHO, DEN/DTEC/L2EC/LCEC, F-30207 Bagnols Sur Ceze, (France); Durand, S. [CEA Saclay, DEN/DM2S/SEMT/LM2S, F-91191 Gif Sur Yvette, (France)

    2008-07-01

    This study focuses on the concrete behavior subjected to moderate temperatures, with a particular emphasis on the transient thermo-hydric stage. A simplified coupled thermo-hydro-mechanical model is developed with the assumption that the gaseous phase is composed uniquely of vapor. Estimations of the mechanical parameters, Biot coefficient and permeability as a function of damage and saturation degree are provided by applying effective-medium approximation schemes. The isotherm adsorption curves are supposed to depend upon both temperature and crack-induced porosity. The effects of damage and parameters linked to transfer (in particular the adsorption curves) on the concrete structure response in the transient phase of heating are then investigated and evaluated. To this aim, the model is applied to the simulation of concrete cylinders with height and diameter of 0.80 m subjected to heating rates of 0.1 and 10 degrees C/min up to 160 degrees C. The numerical results are analyzed, commented and compared with experimental ones in terms of water mass loss, temperatures and gas pressures evolutions. A numerical study indicates that some parameters have a greater influence on the results than others, and that certain coupling terms in the mass conservation equation of water may be neglected. (authors)

  11. Associating a prototypical forbidden food item with guilt or celebration: relationships with indicators of (un)healthy eating and the moderating role of stress and depressive symptoms.

    Science.gov (United States)

    Kuijer, Roeline G; Boyce, Jessica A; Marshall, Emma M

    2015-01-01

    The increase in obesity and the many educational messages prompting us to eat a healthy diet have heightened people's concerns about the effects of food choice on health and weight. An unintended side effect may be that such awareness fuels feelings of guilt and worry about food. Although guilt has the potential to motivate behaviour change, it may also lead to feelings of helplessness and loss of control. The current study examined the relationship between a default association of either 'guilt' or 'celebration' with a prototypical forbidden food item (chocolate cake), indicators of healthy eating and choosing food for mood regulation reasons. Following a 'diathesis-stress' perspective, the moderating roles of depressive symptoms and stress were examined. Although a default association of guilt was found to be harmless under some circumstances (i.e. under low stress), those who associated chocolate cake with guilt (vs. celebration) reported unhealthier eating habits and lower levels of perceived behavioural control over healthy eating when under stress, rated mood regulation reasons for food choice as important irrespective of their current affective state, and did not have more positive attitudes towards healthy eating. Implications for public health messages and interventions will be discussed.

  12. A Helping Hand? The Moderating Role of Leaders' Conflict Management Behavior on the Conflict–Stress Relationship of Employees

    NARCIS (Netherlands)

    Romer, M.; Rispens, Sonja; Giebels, Ellen; Euwema, M.C.

    2012-01-01

    Interpersonal conflict between colleagues within organizations negatively affects employee well-being (e.g., stress). It is unclear how leaders' third-party conflict management behaviors influence the relationship between employee conflict and well-being. In this study, we examine the effects of

  13. A helping hand? : the moderating role of leaders' conflict management behavior on the conflict-stress relationship of employees

    NARCIS (Netherlands)

    Römer, M.; Rispens, S.; Giebels, E.; Euwema, M.

    2012-01-01

    Interpersonal conflict between colleagues within organizations negatively affects employee well-being (e.g., stress). It is unclear how leaders' third-party conflict management behaviors influence the relationship between employee conflict and well-being. In this study, we examine the effects of

  14. Social Support: Main and Moderating Effects on the Relation between Financial Stress and Adjustment among College Students with Disabilities

    Science.gov (United States)

    Murray, Christopher; Lombardi, Allison; Bender, Franklin; Gerdes, Hillary

    2013-01-01

    Students with disabilities are underrepresented in 4-year colleges and universities in the United States and those that do attend are at an increased risk of performing poorly in these settings. These difficulties for college students with disabilities may be compounded by additional stress related to financial concerns. The current study was…

  15. "NR3C1" Methylation as a Moderator of the Effects of Maternal Support and Stress on Insecure Attachment Development

    Science.gov (United States)

    Bosmans, Guy; Young, Jami F.; Hankin, Benjamin L.

    2018-01-01

    We examined the prediction that the interaction between Glucocorticoid Receptor Gene ("NR3C1") methylation, stress, and experienced maternal support predicts anxious and avoidant attachment development. This was tested in a general population sample of 487 children and adolescents (44% boys, M[subscript age] = 11.84, SD[subscript age] =…

  16. Modelling and analysis of radial thermal stresses and temperature ...

    African Journals Online (AJOL)

    user

    The temperature field, heat transfer rate and thermal stresses were investigated with numerical simulation models using FORTRAN FE (finite element) software. ...... specific heats, International Communications in Heat and Mass Transfer, Vol.

  17. Micromagnetic modeling of the effects of stress on magnetic properties

    International Nuclear Information System (INIS)

    Zhu, B.; Lo, C. C. H.; Lee, S. J.; Jiles, D. C.

    2001-01-01

    A micromagnetic model has been developed for investigating the effect of stress on the magnetic properties of thin films. This effect has been implemented by including the magnetoelastic energy term into the Landau - Lifshitz - Gilbert equation. Magnetization curves of a nickel film were calculated under both tensile and compressive stresses of various magnitudes applied along the field direction. The modeling results show that coercivity increased with increasing compressive stress while remanence decreased with increasing tensile stress. The results are in agreement with the experimental data in the literature and can be interpreted in terms of the effects of the applied stress on the irreversible rotation of magnetic moments during magnetization reversal under an applied field. [copyright] 2001 American Institute of Physics

  18. Mathematical model of polyethylene pipe bending stress state

    Science.gov (United States)

    Serebrennikov, Anatoly; Serebrennikov, Daniil

    2018-03-01

    Introduction of new machines and new technologies of polyethylene pipeline installation is usually based on the polyethylene pipe flexibility. It is necessary that existing bending stresses do not lead to an irreversible polyethylene pipe deformation and to violation of its strength characteristics. Derivation of the mathematical model which allows calculating analytically the bending stress level of polyethylene pipes with consideration of nonlinear characteristics is presented below. All analytical calculations made with the mathematical model are experimentally proved and confirmed.

  19. Influence of Hardening Model on Weld Residual Stress Distribution

    Energy Technology Data Exchange (ETDEWEB)

    Mullins, Jonathan; Gunnars, Jens (Inspecta Technology AB, Stockholm (Sweden))

    2009-06-15

    This study is the third stage of a project sponsored by the Swedish Radiation Safety Authority (SSM) to improve the weld residual stress modelling procedures currently used in Sweden. The aim of this study was to determine which material hardening model gave the best agreement with experimentally measured weld residual stress distributions. Two girth weld geometries were considered: 19mm and 65mm thick girth welds with Rin/t ratios of 10.5 and 2.8, respectively. The FE solver ABAQUS Standard v6.5 was used for analysis. As a preliminary step some improvements were made to the welding simulation procedure used in part one of the project. First, monotonic stress strain curves and a mixed isotropic/kinematic hardening model were sourced from the literature for 316 stainless steel. Second, more detailed information was obtained regarding the geometry and welding sequence for the Case 1 weld (compared with phase 1 of this project). Following the preliminary step, welding simulations were conducted using isotropic, kinematic and mixed hardening models. The isotropic hardening model gave the best overall agreement with experimental measurements; it is therefore recommended for future use in welding simulations. The mixed hardening model gave good agreement for predictions of the hoop stress but tended to under estimate the magnitude of the axial stress. It must be noted that two different sources of data were used for the isotropic and mixed models in this study and this may have contributed to the discrepancy in predictions. When defining a mixed hardening model it is difficult to delineate the relative contributions of isotropic and kinematic hardening and for the model used it may be that a greater isotropic hardening component should have been specified. The kinematic hardening model consistently underestimated the magnitude of both the axial and hoop stress and is not recommended for use. Two sensitivity studies were also conducted. In the first the effect of using a

  20. Influence of Hardening Model on Weld Residual Stress Distribution

    International Nuclear Information System (INIS)

    Mullins, Jonathan; Gunnars, Jens

    2009-06-01

    This study is the third stage of a project sponsored by the Swedish Radiation Safety Authority (SSM) to improve the weld residual stress modelling procedures currently used in Sweden. The aim of this study was to determine which material hardening model gave the best agreement with experimentally measured weld residual stress distributions. Two girth weld geometries were considered: 19mm and 65mm thick girth welds with Rin/t ratios of 10.5 and 2.8, respectively. The FE solver ABAQUS Standard v6.5 was used for analysis. As a preliminary step some improvements were made to the welding simulation procedure used in part one of the project. First, monotonic stress strain curves and a mixed isotropic/kinematic hardening model were sourced from the literature for 316 stainless steel. Second, more detailed information was obtained regarding the geometry and welding sequence for the Case 1 weld (compared with phase 1 of this project). Following the preliminary step, welding simulations were conducted using isotropic, kinematic and mixed hardening models. The isotropic hardening model gave the best overall agreement with experimental measurements; it is therefore recommended for future use in welding simulations. The mixed hardening model gave good agreement for predictions of the hoop stress but tended to under estimate the magnitude of the axial stress. It must be noted that two different sources of data were used for the isotropic and mixed models in this study and this may have contributed to the discrepancy in predictions. When defining a mixed hardening model it is difficult to delineate the relative contributions of isotropic and kinematic hardening and for the model used it may be that a greater isotropic hardening component should have been specified. The kinematic hardening model consistently underestimated the magnitude of both the axial and hoop stress and is not recommended for use. Two sensitivity studies were also conducted. In the first the effect of using a

  1. Stress associated with caregiving: an examination of the stress process model among Kenyan Luo elders.

    Science.gov (United States)

    Ice, Gillian H; Sadruddin, Aalyia F A; Vagedes, Amy; Yogo, Jaja; Juma, Elizabeth

    2012-06-01

    Globally, a growing number of grandparents are caring for their grandchildren. The impact and burden associated with increases in custodial grandparenting, however, may differ by culture. In the United States, the caregiving role has been shown to be a significant source of stress for older adults. In cultures in which grandparents are more commonly involved in the care of young children, however, increasing caregiving roles may not be viewed as stressful. This study examines the impact of caregiving on perceived and physiological measures of stress among 640 Luo elders (60+) in western Kenya, where high HIV prevalence among younger-to-middle aged adults has led to a heavy burden of orphan care. Perceived stress levels were measured using the Luo Perceived Stress Scale (LPSS). Salivary cortisol and casual blood pressure were used as biomarkers of stress. Results were analyzed using random mixed effects models. Overall this study showed that caregivers have higher levels of perceived stress than non-caregivers. For women, household composition, including the number of orphans and adults in the homestead impacted perceived stress. Among men, those who perceived caregiving as burdensome had higher perceived stress. Despite the association between caregiving and perceived stress, there was a minimal relationship between caregiving and the two biomarkers of stress. This may be because caregiving is superimposed onto other stressors and therefore has a minimal physiological impact. These results highlight the importance of local context in determining the impact of the caregiving role on older adult well-being. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Resilience as a Moderator of Psychological Health in Situations of Chronic Stress (Burnout) in a Sample of Hospital Nurses.

    Science.gov (United States)

    García-Izquierdo, Mariano; Meseguer de Pedro, Mariano; Ríos-Risquez, Mª Isabel; Sánchez, Mª Isabel Soler

    2018-03-01

    To analyze the role played by resilience in the dimensions that constitute burnout syndrome and, through that, the psychological health of a sample of nurses working at hospital centers. Cross-sectional design, with a questionnaire as the tool. The sample consisted of 537 nurses from three public hospitals in Murcia, Spain. The questionnaire contained measures of the following variables: resilience, the three dimensions of burnout (emotional exhaustion, cynicism, and professional efficacy), and general psychological health, as well as sociodemographic and employment information. The emotional exhaustion and cynicism dimensions of burnout were significantly linked to psychological health in the manner expected, but this was not the case for professional efficacy. A stepwise multiple regression analysis revealed the moderating role of resilience on the emotional exhaustion and cynicism dimensions, as well as on psychological health. This study highlights the moderating role of resilience on burnout and psychological health. The practical implications of the results are discussed for the implementation of measures to increase resilience as a personal resource in order to improve the health and work performance of these professionals. © 2017 Sigma Theta Tau International.

  3. Effect of moderate hypoxia at three acclimation temperatures on stress responses in Atlantic cod with different haemoglobin types

    DEFF Research Database (Denmark)

    Methling, Caroline; Aluru, Neelakanteswar; Vijayan, Mathilakath M

    2010-01-01

    in a difference in stress response to hypoxia exposure. Two hsp70-isoforms (labelled a and b) were detected and they differed in expression in the gills but not in the liver of Atlantic cod. Acclimation temperature significantly affected the expression of hsp70 in the liver, and in an isoform-specific manner...... in the gills. Hypoxia exposure increased the expression of hsp70 in the liver, but not the gills, of cod and this response was not influenced by the acclimation temperature. The expression of hsp70 in both tissues did not differ between fish with different haemoglobin types. Acclimation temperature...... hypoxic exposure influence the organismal and cellular stress responses in Atlantic cod. We hypothesise that HbI-2 fish are more tolerant to short-term hypoxic episodes than HbI-1 fish, and this adaptation may be independent of tissue hsp70 expression....

  4. Relation between aggression exposure in adolescence and adult posttraumatic stress symptoms: Moderating role of the parasympathetic nervous system.

    Science.gov (United States)

    Barry, Samantha A; Rabkin, Ari N; Olezeski, Christy L; Rivers, Alison J; Gordis, Elana B

    2015-03-15

    The present study examines the impact of the parasympathetic nervous system (PNS), as measured by respiratory sinus arrhythmia (RSA), on the link between family aggression experienced during adolescence and posttraumatic stress symptoms during young adulthood. Participants completed retrospective self-report measures of interparental aggression and harsh parenting exposure during adolescence and measures of current posttraumatic stress symptoms. RSA indexed PNS activity. Among females, the three-way interaction between harsh parenting, interparental aggression, and resting RSA was significant in accounting for young adulthood PTSD symptoms. At higher values of resting RSA and higher levels of interparental aggression exposure, harsh parenting experienced during adolescence was positively associated with adulthood PTSD symptoms. Among males, adolescent aggression exposure and resting RSA did not significantly account for variation in adulthood PTSD symptoms. Thus, this study suggests that resting PNS activity may play an important role in the relationship between stressors during adolescence and later PTSD in females. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Stress transfer modeling in CNT reinforced composites using continuum mechanics

    International Nuclear Information System (INIS)

    Chaboki Khiabani, A.; Sadrnejad, S. A.; Yahyaeii, M.

    2008-01-01

    Because of the substantial difference in stiffness between matrix and nano tube in CNT composite, the stress transfer between them controls their mechanical properties. This paper investigates the said issue, analytically and numerically, in axial load using representative volume element. The analytical model was established based on the modified Cox's shear lag model with the use of some simplified assumptions. Some, in the developed shear lag model, the CNT assumes hollow fiber. Solving the governing differential equation. led the high shear stress, in interface especially in the CNT cap. In addition, some finite element models were performed with different aspect ratios and the shear stress pattern especially in interface was calculated numerically. Despite some simplified assumptions that were performed with these two models such as elastic behavior and full connectivity, and the comparison of their results with other numerical models show adequate agreement

  6. Stress potentiates decision biases: A stress induced deliberation-to-intuition (SIDI model

    Directory of Open Access Journals (Sweden)

    Rongjun Yu

    2016-06-01

    Full Text Available Humans often make decisions in stressful situations, for example when the stakes are high and the potential consequences severe, or when the clock is ticking and the task demand is overwhelming. In response, a whole train of biological responses to stress has evolved to allow organisms to make a fight-or-flight response. When under stress, fast and effortless heuristics may dominate over slow and demanding deliberation in making decisions under uncertainty. Here, I review evidence from behavioral studies and neuroimaging research on decision making under stress and propose that stress elicits a switch from an analytic reasoning system to intuitive processes, and predict that this switch is associated with diminished activity in the prefrontal executive control regions and exaggerated activity in subcortical reactive emotion brain areas. Previous studies have shown that when stressed, individuals tend to make more habitual responses than goal-directed choices, be less likely to adjust their initial judgment, and rely more on gut feelings in social situations. It is possible that stress influences the arbitration between the emotion responses in subcortical regions and deliberative processes in the prefrontal cortex, so that final decisions are based on unexamined innate responses. Future research may further test this ‘stress induced deliberation-to-intuition’ (SIDI model and examine its underlying neural mechanisms.

  7. A theoretical model of strong and moderate El Niño regimes

    Science.gov (United States)

    Takahashi, Ken; Karamperidou, Christina; Dewitte, Boris

    2018-02-01

    The existence of two regimes for El Niño (EN) events, moderate and strong, has been previously shown in the GFDL CM2.1 climate model and also suggested in observations. The two regimes have been proposed to originate from the nonlinearity in the Bjerknes feedback, associated with a threshold in sea surface temperature (T_c ) that needs to be exceeded for deep atmospheric convection to occur in the eastern Pacific. However, although the recent 2015-16 EN event provides a new data point consistent with the sparse strong EN regime, it is not enough to statistically reject the null hypothesis of a unimodal distribution based on observations alone. Nevertheless, we consider the possibility suggestive enough to explore it with a simple theoretical model based on the nonlinear Bjerknes feedback. In this study, we implemented this nonlinear mechanism in the recharge-discharge (RD) ENSO model and show that it is sufficient to produce the two EN regimes, i.e. a bimodal distribution in peak surface temperature (T) during EN events. The only modification introduced to the original RD model is that the net damping is suppressed when T exceeds T_c , resulting in a weak nonlinearity in the system. Due to the damping, the model is globally stable and it requires stochastic forcing to maintain the variability. The sustained low-frequency component of the stochastic forcing plays a key role for the onset of strong EN events (i.e. for T>T_c ), at least as important as the precursor positive heat content anomaly (h). High-frequency forcing helps some EN events to exceed T_c , increasing the number of strong events, but the rectification effect is small and the overall number of EN events is little affected by this forcing. Using the Fokker-Planck equation, we show how the bimodal probability distribution of EN events arises from the nonlinear Bjerknes feedback and also propose that the increase in the net feedback with increasing T is a necessary condition for bimodality in the RD

  8. Modeling of grain boundary stresses in Alloy 600

    Energy Technology Data Exchange (ETDEWEB)

    Kozaczek, K.J. [Oak Ridge National Lab., TN (United States); Sinharoy, A.; Ruud, C.O. [Pennsylvania State Univ., University Park, PA (United States); Mcllree, A.R. [Electric Power Research Inst., Palo Alto, CA (United States)

    1995-04-01

    Corrosive environments combined with high stress levels and susceptible microstructures can cause intergranular stress corrosion cracking (IGSCC) of Alloy 600 components on both primary and secondary sides of pressurized water reactors. One factor affecting the IGSCC is intergranular carbide precipitation controlled by heat treatment of Alloy 600. This study is concerned with analysis of elastic stress fields in vicinity of M{sub 7}C{sub 3} and M{sub 23}C{sub 6} carbides precipitated in the matrix and at a grain boundary triple point. The local stress concentration which can lead to IGSCC initiation was studied using a two-dimensional finite element model. The intergranular precipitates are more effective stress raisers than the intragranular precipitates. The combination of the elastic property mismatch and the precipitate shape can result in a local stress field substantially different than the macroscopic stress. The maximum local stresses in the vicinity of the intergranular precipitate were almost twice as high as the applied stress.

  9. Approaches to modeling the development of physiological stress responsivity.

    Science.gov (United States)

    Hinnant, J Benjamin; Philbrook, Lauren E; Erath, Stephen A; El-Sheikh, Mona

    2018-05-01

    Influential biopsychosocial theories have proposed that some developmental periods in the lifespan are potential pivot points or opportunities for recalibration of stress response systems. To date, however, there have been few longitudinal studies of physiological stress responsivity and no studies comparing change in physiological stress responsivity across developmental periods. Our goals were to (a) address conceptual and methodological issues in studying the development of physiological stress responsivity within and between individuals, and (b) provide an exemplar for evaluating development of responsivity to stress in the parasympathetic nervous system, comparing respiratory sinus arrhythmia (RSA) responsivity from middle to late childhood with middle to late adolescence. We propose the use of latent growth modeling of stress responsivity that includes time-varying covariates to account for conceptual and methodological issues in the measurement of physiological stress responsivity. Such models allow researchers to address key aspects of developmental sensitivity including within-individual variability, mean level change over time, and between-individual variability over time. In an empirical example, we found significant between-individual variability over time in RSA responsivity to stress during middle to late childhood but not during middle to late adolescence, suggesting that childhood may be a period of greater developmental sensitivity at the between-individual level. © 2017 Society for Psychophysiological Research.

  10. Prenatal stress exposure, oxytocin receptor gene (OXTR) methylation, and child autistic traits: The moderating role of OXTR rs53576 genotype.

    Science.gov (United States)

    Rijlaarsdam, Jolien; van IJzendoorn, Marinus H; Verhulst, Frank C; Jaddoe, Vincent W V; Felix, Janine F; Tiemeier, Henning; Bakermans-Kranenburg, Marian J

    2017-03-01

    Findings of studies investigating OXTR SNP rs53576 (G-A) variation in social behavior have been inconsistent, possibly because DNA methylation after stress exposure was eliminated from consideration. Our goal was to examine OXTR rs53576 allele-specific sensitivity for neonatal OXTR DNA methylation in relation to (1) a prenatal maternal stress composite, and (2) child autistic traits. Prospective data from fetal life to age 6 years were collected in a total of 743 children participating in the Generation R Study. Prenatal maternal stress exposure was uniquely associated with child autistic traits but was unrelated to OXTR methylation across both OXTR rs53576 G-allele homozygous children and A-allele carriers. For child autistic traits in general and social communication problems in particular, we observed a significant OXTR rs53576 genotype by OXTR methylation interaction in the absence of main effects, suggesting that opposing effects cancelled each other out. Indeed, OXTR methylation levels were positively associated with social problems for OXTR rs53576 G-allele homozygous children but not for A-allele carriers. These results highlight the importance of incorporating epi-allelic information and support the role of OXTR methylation in child autistic traits. Autism Res 2017, 10: 430-438. © 2016 International Society for Autism Research, Wiley Periodicals, Inc. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.

  11. Initiation model for intergranular stress corrosion cracking in BWR pipes

    International Nuclear Information System (INIS)

    Hishida, Mamoru; Kawakubo, Takashi; Nakagawa, Yuji; Arii, Mitsuru.

    1981-01-01

    Discussions were made on the keys of intergranular stress corrosion cracking of austenitic stainless steel in high-temperature water in laboratories and stress corrosion cracking incidents in operating plants. Based on these discussions, a model was set up of intergranular stress corrosion cracking initiation in BWR pipes. Regarding the model, it was presumed that the intergranular stress corrosion cracking initiates during start up periods whenever heat-affected zones in welded pipes are highly sensitized and suffer dynamic strain in transient water containing dissolved oxygen. A series of BWR start up simulation tests were made by using a flowing autoclave system with slow strain rate test equipment. Validity of the model was confirmed through the test results. (author)

  12. Family boundary characteristics, work-family conflict and life satisfaction: A moderated mediation model.

    Science.gov (United States)

    Qiu, Lin; Fan, Jinyan

    2015-10-01

    Although work-family border and boundary theory suggest individuals' boundary characteristics influence their work-family relationship, it is largely unknown how boundary flexibility and permeability mutually influence work-family conflict and subsequent employee outcomes. Moreover, the existing work-family conflict research has been mainly conducted in the United States and other Western countries. To address these gaps in the work-family literature, the present study examines a moderated mediation model regarding how family boundary characteristics may influence individuals' work-family conflict and life satisfaction with a sample of 278 Chinese full-time employees. Results showed that employees' family flexibility negatively related to their perceived work interference with family (WIF) and family interference with work (FIW), and both these two relationships were augmented by individuals' family permeability. In addition, WIF mediated the relationship between family flexibility and life satisfaction; the indirect effect of family flexibility on life satisfaction via WIF was stronger for individuals with higher family permeability. The theoretical and managerial implications of these findings are discussed. © 2014 International Union of Psychological Science.

  13. Rapid development of cardiac dysfunction in a canine model of insulin resistance and moderate obesity.

    Science.gov (United States)

    Broussard, Josiane L; Nelson, Michael D; Kolka, Cathryn M; Bediako, Isaac Asare; Paszkiewicz, Rebecca L; Smith, Laura; Szczepaniak, Edward W; Stefanovski, Darko; Szczepaniak, Lidia S; Bergman, Richard N

    2016-01-01

    The worldwide incidence of obesity and diabetes continues to rise at an alarming rate. A major cause of the morbidity and mortality associated with obesity and diabetes is heart disease, yet the mechanisms that lead to cardiovascular complications remain unclear. We performed cardiac MRI to assess left ventricular morphology and function during the development of moderate obesity and insulin resistance in a well-established canine model (n = 26). To assess the influence of dietary fat composition, we randomised animals to a traditional lard diet (rich in saturated and monounsaturated fat; n = 12), a salmon oil diet (rich in polyunsaturated fat; n = 8) or a control diet (n = 6). High-fat feeding with lard increased body weight and fasting insulin and markedly reduced insulin sensitivity. Lard feeding also significantly reduced left ventricular function, evidenced by a worsening of circumferential strain and impairment in left ventricular torsion. High-fat feeding with salmon oil increased body weight; however, salmon oil feeding did not impair insulin sensitivity or cardiac function. These data emphasise the importance of dietary fat composition on both metabolic and cardiac function, and have important implications for the relationship between diet and health.

  14. Relationship between work-family balance and job satisfaction among employees in China: A moderated mediation model.

    Science.gov (United States)

    Yu, Yue; Wang, Yuchen; Zhang, Jianxin

    2017-09-01

    Previous studies have revealed the association between work-family balance and job satisfaction. The present research further explored the underlying mechanism of this association and aimed to provide a moderated mediation model to explain if personality traits moderate the relationship between work-family balance and job satisfaction through work engagement. A cross-sectional study was conducted in which 263 employees from a petrochemical enterprise in China completed self-report questionnaires including the Work-Family Balance Scale, the Utrecht Work Engagement Scale, the Big Five Inventory-10, and the Job Satisfaction Scale. Hierarchical regression analysis and structural equation modeling showed that work engagement partially mediated the relationship between work-family balance and job satisfaction, and the indirect effect was further moderated only by extraversion. Therefore, an integrative moderated mediation model was proposed wherein work-family balance boosts job satisfaction by first enhancing employees' work engagement, while the indirect effect was in turn moderated by extraversion. The results suggest that interventions for improving job satisfaction may be enhanced by targeting work engagement, especially for employees with higher extraversion. © 2017 The Institute of Psychology, Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

  15. New plastic plane stress model for concrete

    International Nuclear Information System (INIS)

    Winnicki, A.; Cichon, Cz.

    1993-01-01

    In the paper a description of concrete behaviour in the plane stress case is given on the basis of the modified bounding surface plasticity theory. Three independent plastic mechanisms have been introduced describing axiatoric and deviatoric plastic strains and their coupling. All the new analytical formulae for material functions being in agreement with experiments and loading/unloading criteria have been proposed. In addition, for the proper description of concrete behaviour in tension a new, separate function of bounding surface shrinkage has been introduced. (author)

  16. Modelling of the Residual Stress State in a new Type of Residual Stress Specimen

    DEFF Research Database (Denmark)

    Jakobsen, Johnny; Andreasen, Jens Henrik

    2014-01-01

    forms the experimental case which is analysed. A FE model of the specimen is used for analysing the curing history and the residual stress build up. The model is validated against experimental strain data which are recorded by a Fibre Brag Grating sensor and good agreement has been achieved.......The paper presents a study on a new type residual stress specimen which is proposed as a simple way to conduct experimental validation for model predictions. A specimen comprising of a steel plate with circular hole embedded into a stack of CSM glass fibre and further infused with an epoxy resin...

  17. Examining the role of Coulomb static stress transfer in injection-induced seismicity: a generic modeling approach

    Science.gov (United States)

    Brown, M. R. M.; Ge, S.

    2017-12-01

    Increased pore pressure decreasing the effective stress on a critically stressed fault has been the accepted mechanism for injection-induced seismicity. This, however, is an over simplified approach that does not take into account the coupled hydro-mechanical effects. In addition, this approach leaves out a possible key stressor in the system, the earthquakes. Earthquakes are known to interact with each other by Coulomb static stress transfer, the process of permanent stress change caused by movement on a fault. In areas of induced seismicity, many small to moderate earthquakes can occur adding to the stress in the system via Coulomb static stress transfer. Here we ask: Is the Coulomb static stress transfer from the earthquakes as important as the pore pressure increase or stress changes caused by coupled hydro-mechanical processes? Is there a point where the Coulomb static stress transfer from the earthquakes becomes the controlling process for inducing future earthquakes? How does the effect of many small earthquakes compare to a few larger events in terms of Coulomb static stress transfer? In this study, we use hydrologic and coupled hydro-mechanical models and USGS Coulomb 3 to assess the importance of induced earthquakes in terms of the stress change in the system. Realistic scenarios of wastewater injection and earthquake magnitude-frequency distributions are used to develop generic models. Model variables and data are varied to evaluate the range of possible outcomes. Preliminary results show that the stress change associated with injection is of the same order of magnitude as the cumulative Coulomb static stress change of a series of small (1

  18. The calm mouse: an animal model of stress reduction.

    Science.gov (United States)

    Gurfein, Blake T; Stamm, Andrew W; Bacchetti, Peter; Dallman, Mary F; Nadkarni, Nachiket A; Milush, Jeffrey M; Touma, Chadi; Palme, Rupert; Di Borgo, Charles Pozzo; Fromentin, Gilles; Lown-Hecht, Rachel; Konsman, Jan Pieter; Acree, Michael; Premenko-Lanier, Mary; Darcel, Nicolas; Hecht, Frederick M; Nixon, Douglas F

    2012-05-09

    Chronic stress is associated with negative health outcomes and is linked with neuroendocrine changes, deleterious effects on innate and adaptive immunity, and central nervous system neuropathology. Although stress management is commonly advocated clinically, there is insufficient mechanistic understanding of how decreasing stress affects disease pathogenesis. Therefore, we have developed a "calm mouse model" with caging enhancements designed to reduce murine stress. Male BALB/c mice were divided into four groups: control (Cntl), standard caging; calm (Calm), large caging to reduce animal density, a cardboard nest box for shelter, paper nesting material to promote innate nesting behavior, and a polycarbonate tube to mimic tunneling; control exercise (Cntl Ex), standard caging with a running wheel, known to reduce stress; and calm exercise (Calm Ex), calm caging with a running wheel. Calm, Cntl Ex and Calm Ex animals exhibited significantly less corticosterone production than Cntl animals. We also observed changes in spleen mass, and in vitro splenocyte studies demonstrated that Calm Ex animals had innate and adaptive immune responses that were more sensitive to acute handling stress than those in Cntl. Calm animals gained greater body mass than Cntl, although they had similar food intake, and we also observed changes in body composition, using magnetic resonance imaging. Together, our results suggest that the Calm mouse model represents a promising approach to studying the biological effects of stress reduction in the context of health and in conjunction with existing disease models.

  19. Analysis of the positive ionospheric response to a moderate geomagnetic storm using a global numerical model

    Directory of Open Access Journals (Sweden)

    A. A. Namgaladze

    2000-04-01

    Full Text Available Current theories of F-layer storms are discussed using numerical simulations with the Upper Atmosphere Model, a global self-consistent, time dependent numerical model of the thermosphere-ionosphere-plasmasphere-magnetosphere system including electrodynamical coupling effects. A case study of a moderate geomagnetic storm at low solar activity during the northern winter solstice exemplifies the complex storm phenomena. The study focuses on positive ionospheric storm effects in relation to thermospheric disturbances in general and thermospheric composition changes in particular. It investigates the dynamical effects of both neutral meridional winds and electric fields caused by the disturbance dynamo effect. The penetration of short-time electric fields of magnetospheric origin during storm intensification phases is shown for the first time in this model study. Comparisons of the calculated thermospheric composition changes with satellite observations of AE-C and ESRO-4 during storm time show a good agreement. The empirical MSISE90 model, however, is less consistent with the simulations. It does not show the equatorward propagation of the disturbances and predicts that they have a gentler latitudinal gradient. Both theoretical and experimental data reveal that although the ratio of [O]/[N2] at high latitudes decreases significantly during the magnetic storm compared with the quiet time level, at mid to low latitudes it does not increase (at fixed altitudes above the quiet reference level. Meanwhile, the ionospheric storm is positive there. We conclude that the positive phase of the ionospheric storm is mainly due to uplifting of ionospheric F2-region plasma at mid latitudes and its equatorward movement at low latitudes along geomagnetic field lines caused by large-scale neutral wind circulation and the passage of travelling atmospheric disturbances (TADs. The calculated zonal electric field disturbances also help to create the positive ionospheric

  20. Analysis of the positive ionospheric response to a moderate geomagnetic storm using a global numerical model

    Directory of Open Access Journals (Sweden)

    A. A. Namgaladze

    Full Text Available Current theories of F-layer storms are discussed using numerical simulations with the Upper Atmosphere Model, a global self-consistent, time dependent numerical model of the thermosphere-ionosphere-plasmasphere-magnetosphere system including electrodynamical coupling effects. A case study of a moderate geomagnetic storm at low solar activity during the northern winter solstice exemplifies the complex storm phenomena. The study focuses on positive ionospheric storm effects in relation to thermospheric disturbances in general and thermospheric composition changes in particular. It investigates the dynamical effects of both neutral meridional winds and electric fields caused by the disturbance dynamo effect. The penetration of short-time electric fields of magnetospheric origin during storm intensification phases is shown for the first time in this model study. Comparisons of the calculated thermospheric composition changes with satellite observations of AE-C and ESRO-4 during storm time show a good agreement. The empirical MSISE90 model, however, is less consistent with the simulations. It does not show the equatorward propagation of the disturbances and predicts that they have a gentler latitudinal gradient. Both theoretical and experimental data reveal that although the ratio of [O]/[N2] at high latitudes decreases significantly during the magnetic storm compared with the quiet time level, at mid to low latitudes it does not increase (at fixed altitudes above the quiet reference level. Meanwhile, the ionospheric storm is positive there. We conclude that the positive phase of the ionospheric storm is mainly due to uplifting of ionospheric F2-region plasma at mid latitudes and its equatorward movement at low latitudes along geomagnetic field lines caused by large-scale neutral wind circulation and the passage of travelling atmospheric disturbances (TADs. The calculated zonal electric field disturbances also help

  1. Modelling of the Global Geopotential Energy & Stress Field

    DEFF Research Database (Denmark)

    Schiffer, Christian; Nielsen, S.B.

    Lateral density and topography variations yield in and important contribution to the lithospheric stress field. The leading quantity is the Geopotential Energy, the integrated lithostatic pressure in a rock column. The horizontal gradient of this quantity is related to horizontal stresses through...... the Equations of equilibrium of stresses. The Geopotential Energy furthermore can be linearly related to the Geoid under assumption of local isostasy. Satellite Geoid measurements contain, however, also non-isostatic deeper mantle responses of long wavelength. Unfortunately, high-pass filtering of the Geoid...... flow in the presence of local isostasy and a steady state geotherm. Subsequently we use a FEM code to solve the Equations of equilibrium of stresses for a three dimensional elastic shell. The modelled results are shown and compared with the global stress field and other publications....

  2. Wine and oxidative stress: up-to-date evidence of the effects of moderate wine consumption on oxidative damage in humans.

    Science.gov (United States)

    Covas, María Isabel; Gambert, Philippe; Fitó, Montserrat; de la Torre, Rafael

    2010-02-01

    Wine and alcohol consumption has been considered to be protective against coronary heart disease development, an oxidative stress associated disease. Wine contains polyphenols displaying antioxidant properties tested in in vitro and in vivo studies. Due to this, a general consensus exists, both among the general public and the scientific community, that wine, particularly red wine, is an antioxidant beverage. Alcohol consumption, however, is associated with oxidative damage. Several studies have been carried out on the antioxidant health benefits of wine and wine polyphenols. However, adequate scientific evidence (Level I or II) is required to be provided before recommendations or statements which can reach the general public can be formulated. Here, we summarize the state of the art of the up-to-date body of knowledge, and the extent to which there exists evidence of the benefits of moderate wine consumption on oxidative damage in humans. From the available data, there is no evidence, at present, that sustained wine consumption provides antioxidant benefits in healthy volunteers other than to counteract a possible pro-oxidative effect of the alcohol. On the contrary, data on the antioxidant protective effect of red wine in oxidative stress situations are promising. In this way, the postprandial oxidative stress after a meal, despite the diversity of biomarkers used for its evaluation, is counteracted by the ingestion of wine. Further studies are warranted. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.

  3. Scalp Nerve Block pada Kraniotomi Evakuasi Pasien Moderate Head Injury dengan Subdural Hemorrhage dan Intracerebral Hemorrhage Frontotemporoparietal Dekstra Mencegah Stress Response Selama dan Pascabedah

    Directory of Open Access Journals (Sweden)

    Mariko Gunadi

    2013-12-01

    Full Text Available Skin incision and craniotomy are recognized as an acute noxious stimulation during intracranial surgery which may result in stress response causing an increase in intracranial pressure. Scalp nerve block may be effective in reducing stress response. It can also be used to provide post-operative analgesia. A twenty two years old male with moderate head injury, subdural hemorrhage, intracerebral hemorrhage at right fronto-temporo-parietal region underwent evacuation craniotomy with combined scalp nerve block and general anesthesia at Dr. Hasan General Sadikin Hospital Bandung on August 14th 2012. After induction and before incision of the skin, a scalp nerve block was performed using 0.5% bupivacaine. Hemodynamic (blood pressure and heart rate changes after incision of the skin and craniotomy were not significant, and so was post-operative blood glucose concentration. Post-operative analgetic was given eight hours after the block. The result demonstrates that scalp nerve block using 0.5% bupivacaine successfully blunts stress response and can be used as post-operative analgesia.

  4. A structural model of the dimensions of teacher stress.

    Science.gov (United States)

    Boyle, G J; Borg, M G; Falzon, J M; Baglioni, A J

    1995-03-01

    A comprehensive survey of teacher stress, job satisfaction and career commitment among 710 full-time primary school teachers was undertaken by Borg, Riding & Falzon (1991) in the Mediterranean islands of Malta and Gozo. A principal components analysis of a 20-item sources of teacher stress inventory had suggested four distinct dimensions which were labelled: Pupil Misbehaviour, Time/Resource Difficulties, Professional Recognition Needs, and Poor Relationships, respectively. To check on the validity of the Borg et al. factor solution, the group of 710 teachers was randomly split into two separate samples. Exploratory factor analysis was carried out on the data from Sample 1 (N = 335), while Sample 2 (N = 375) provided the cross-validational data for a LISREL confirmatory factor analysis. Results supported the proposed dimensionality of the sources of teacher stress (measurement model), along with evidence of an additional teacher stress factor (Workload). Consequently, structural modelling of the 'causal relationships' between the various latent variables and self-reported stress was undertaken on the combined samples (N = 710). Although both non-recursive and recursive models incorporating Poor Colleague Relations as a mediating variable were tested for their goodness-of-fit, a simple regression model provided the most parsimonious fit to the empirical data, wherein Workload and Student Misbehaviour accounted for most of the variance in predicting teaching stress.

  5. Internal stress model for pre-primary stage of low-stress creep

    International Nuclear Information System (INIS)

    Kloc, L

    2010-01-01

    Initial transient stage in low-stress creep experiments was observed in all such experiments. Recently, evidences were presented that this stage cannot be considered as a normal creep primary stage, though the shape of the creep curve is similar. The strain reached during this so called pre-primary stage is fully recoverable upon unloading; the internal stresses must play important role in the effect. Model of standard linear anelastic solid was modified by introduction of creeping body instead of viscous dashpot. Both power law and hyperbolic sine creep law were used to fit observed creep curves of model and structural materials. Mainly the model using hyeprbolic sine creep law provides good fit to individual creep curves and sets of creep curves at different stresses.

  6. Transient Heating and Thermomechanical Stress Modeling of Ceramic HEPA Filters

    Energy Technology Data Exchange (ETDEWEB)

    Bogle, Brandon [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kelly, James [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Haslam, Jeffrey [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-09-29

    The purpose of this report is to showcase an initial finite-element analysis model of a ceramic High-Efficiency Particulate (HEPA) Air filter design. Next generation HEPA filter assemblies are being developed at LLNL to withstand high-temperature fire scenarios by use of ceramics and advanced materials. The filters are meant for use in radiological and nuclear facilities, and are required to survive 500°C fires over an hour duration. During such conditions, however, collecting data under varying parameters can be challenging; therefore, a Finite Element Analysis model of the filter was conducted using COMSOL ® Multiphysics to analyze the effects of fire. Finite Element Analysis (FEA) modelling offers several opportunities: researchers can quickly and easily consider impacts of potential design changes, material selection, and flow characterization on filter performance. Specifically, this model provides stress references for the sealant at high temperatures. Modeling of full filter assemblies was deemed inefficient given the computational requirements, so a section of three tubes from the assembly was modeled. The model looked at the transient heating and thermomechanical stress development during a 500°C air flow at 6 CFM. Significant stresses were found at the ceramic-metal interfaces of the filter, and conservative temperature profiles at locations of interest were plotted. The model can be used for the development of sealants that minimize stresses at the ceramic-metal interface. Further work on the model would include the full filter assembly and consider heat losses to make more accurate predictions.

  7. Gender Differences in Animal Models of Posttraumatic Stress Disorder

    Directory of Open Access Journals (Sweden)

    Hagit Cohen

    2011-01-01

    Full Text Available Epidemiological studies report higher prevalence rates of stress-related disorders such as acute stress disorder and post-traumatic stress disorder (PTSD in women than in men following exposure to trauma. It is still not clear whether this greater prevalence in woman reflects a greater vulnerability to stress-related psychopathology. A number of individual and trauma-related characteristics have been hypothesized to contribute to these gender differences in physiological and psychological responses to trauma, differences in appraisal, interpretation or experience of threat, coping style or social support. In this context, the use of an animal model for PTSD to analyze some of these gender-related differences may be of particular utility. Animal models of PTSD offer the opportunity to distinguish between biological and socio-cultural factors, which so often enter the discussion about gender differences in PTSD prevalence.

  8. Computational stress and damage modelling for rolling contact fatigue

    DEFF Research Database (Denmark)

    Cerullo, Michele

    Rolling contact fatigue in radial roller bearings is studied by means of a 2D plane strain nite element program. The Dang Van multiaxial fatigue criterion is firstly used, in a macroscopic study modeling the bearing raceway, to investigate the region where fatigue cracks are more likely to nucleate...... and of compressive residual stresses are also analyzed. The stress history of a material point at the depth where the maximum Dang Van damage factor is reached is then recorded and used in a subsequent micro-mechanical analysis. The stress history is applied as periodic boundary conditions in a representative volume...

  9. Use of Video Modeling to Teach Extinguishing of Cooking Related Fires to Individuals with Moderate Intellectual Disabilities

    Science.gov (United States)

    Mechling, Linda C.; Gast, David L.; Gustafson, Melissa R.

    2009-01-01

    This study evaluated the effectiveness of video modeling to teach fire extinguishing behaviors to three young adults with moderate intellectual disabilities. A multiple probe design across three fire extinguishing behaviors and replicated across three students was used to evaluate the effectiveness of the video-based program. Results indicate that…

  10. Regulatory focus at work : the moderating role of regulatory focus in the job demands-resources model

    NARCIS (Netherlands)

    Brenninkmeijer, V.; Demerouti, E.; Blanc, Le P.M.; Emmerik, van I.J.H.

    2010-01-01

    Purpose – The purpose of this study is to examine the moderating role of regulatory focus in the job demands-resources model. Design/methodology/approach – A questionnaire survey was conducted among 146 teachers in secondary education. It was expected that detrimental effects of job demands (i.e.

  11. Study of the Influence of Social Relationships among Students on Knowledge Building Using a Moderately Constructivist Learning Model

    Science.gov (United States)

    Alonso, Fernando; Manrique, Daniel; Martínez, Loïc; Viñes, José M.

    2015-01-01

    The main objective of higher education institutions is to educate students to high standards to proficiently perform their role in society. Elsewhere we presented empirical evidence illustrating that the use of a blended learning approach to the learning process that applies a moderate constructivist e-learning instructional model improves…

  12. Keep Up the Good Work! Age-Moderated Mediation Model on Intention to Retire

    Directory of Open Access Journals (Sweden)

    Paola Dordoni

    2017-10-01

    Full Text Available In European nations, the aging of the workforce is a major issue which is increasingly addressed both in national and organizational policies in order to sustain older workers' employability and to encourage longer working lives. Particularly older workers' employability can be viewed an important issue as this has the potential to motivate them for their work and change their intention to retire. Based on lifespan development theories and Van der Heijden's ‘employability enhancement model’, this paper develops and tests an age-moderated mediation model (which refers to the processes that we want to test in this model, linking older workers' (55 years old and over perceptions of job support for learning (job-related factor and perceptions of negative age stereotypes on productivity (organizational factor, on the one hand, and their intention to retire, on the other hand, via their participation in employability enhancing activities, being the mediator in our model. A total of 2,082 workers aged 55 years and above were included in the analyses. Results revealed that the two proposed relationships between the predictors and intention to retire were mediated by participation in employability enhancing activities, reflecting two mechanisms through which work context affects intention to retire (namely ‘a gain spiral and a loss spiral’. Multi-Group SEM analyses, distinguishing between two age groups (55–60 and 61–65 years old, revealed different paths for the two distinguished groups of older workers. Employability mediated the relationship between perceptions of job support for learning and intention to retire in both age groups, whereas it only mediated the relationship between perceptions of negative age stereotypes and intention to retire in the 55–60 group. From our empirical study, we may conclude that employability is an important factor in the light of older workers' intention to retire. In order to motivate this category of

  13. Modeling the origins of mammalian sociality: moderate evidence for matrilineal signatures in mouse lemur vocalizations.

    Science.gov (United States)

    Kessler, Sharon E; Radespiel, Ute; Hasiniaina, Alida I F; Leliveld, Lisette M C; Nash, Leanne T; Zimmermann, Elke

    2014-02-20

    moderately distinctive by matriline. Because sleeping groups consisted of close maternal kin, both genetics and social learning may have generated these acoustic signatures. As mouse lemurs are models for solitary foragers, we recommend further studies testing whether the lemurs use these calls to recognize kin. This would enable further modeling of how kin recognition in ancestral species could have shaped the evolution of complex sociality.

  14. Model and calculation of in situ stresses in anisotropic formations

    Energy Technology Data Exchange (ETDEWEB)

    Yuezhi, W.; Zijun, L.; Lixin, H. [Jianghan Petroleum Institute, (China)

    1997-08-01

    In situ stresses in transversely isotropic material in relation to wellbore stability have been investigated. Equations for three horizontal in- situ stresses and a new formation fracture pressure model were described, and the methodology for determining the elastic parameters of anisotropic rocks in the laboratory was outlined. Results indicate significantly smaller differences between theoretically calculated pressures and actual formation pressures than results obtained by using the isotropic method. Implications for improvements in drilling efficiency were reviewed. 13 refs., 6 figs.

  15. Computational Psychometrics for Modeling System Dynamics during Stressful Disasters

    Directory of Open Access Journals (Sweden)

    Pietro Cipresso

    2017-08-01

    Full Text Available Disasters can be very stressful events. However, computational models of stress require data that might be very difficult to collect during disasters. Moreover, personal experiences are not repeatable, so it is not possible to collect bottom-up information when building a coherent model. To overcome these problems, we propose the use of computational models and virtual reality integration to recreate disaster situations, while examining possible dynamics in order to understand human behavior and relative consequences. By providing realistic parameters associated with disaster situations, computational scientists can work more closely with emergency responders to improve the quality of interventions in the future.

  16. Modelling of stresses generated in steels by phase transformations

    International Nuclear Information System (INIS)

    Dudek, K.; Glowacki, M.; Pietrzyk, M.

    1999-01-01

    Numerical model describing stresses arising during phase transformations in steels products is presented. The full model consists of three components. The first component uses finite element solution of Fourier equation for an evaluation of the temperature field inside the sample. The second component predicts kinetics of phase transformation occurring during cooling of steel products. Coupling of these two components allows prediction of structure and properties of final products at room temperature. The third component uses elastic-plastic finite element model for prediction of stresses caused by non-uniform temperatures and by changes of volume during transformations. Typical results of simulations performed for cooling of rails after hot rolling are presented. (author)

  17. Statistical model of stress corrosion cracking based on extended

    Indian Academy of Sciences (India)

    The mechanism of stress corrosion cracking (SCC) has been discussed for decades. Here I propose a model of SCC reflecting the feature of fracture in brittle manner based on the variational principle under approximately supposed thermal equilibrium. In that model the functionals are expressed with extended forms of ...

  18. Stress and adaptation : Toward ecologically relevant animal models

    NARCIS (Netherlands)

    Koolhaas, Jaap M.; Boer, Sietse F. de; Buwalda, Bauke

    Animal models have contributed considerably to the current understanding of mechanisms underlying the role of stress in health and disease. Despite the progress made already, much more can be made by more carefully exploiting animals' and humans' shared biology, using ecologically relevant models.

  19. In-core LOCA-s: analytical solution for the delayed mixing model for moderator poison concentration

    International Nuclear Information System (INIS)

    Firla, A.P.

    1995-01-01

    Solutions to dynamic moderator poison concentration model with delayed mixing under single pressure tube / calandria tube rupture scenario are discussed. Such a model is described by a delay differential equation, and for such equations the standard ways of solution are not directly applicable. In the paper an exact, direct time-domain analytical solution to the delayed mixing model is presented and discussed. The obtained solution has a 'marching' form and is easy to calculate numerically. Results of the numerical calculations based on the analytical solution indicate that for the expected range of mixing times the existing uniform mixing model is a good representation of the moderator poison mixing process for single PT/CT breaks. However, for postulated multi-pipe breaks ( which is very unlikely to occur ) the uniform mixing model is not adequate any more; at the same time an 'approximate' solution based on Laplace transform significantly overpredicts the rate of poison concentration decrease, resulting in excessive increase in the moderator dilution factor. In this situation the true, analytical solution must be used. The analytical solution presented in the paper may also serve as a bench-mark test for the accuracy of the existing poison mixing models. Moreover, because of the existing oscillatory tendency of the solution, special care must be taken in using delay differential models in other applications. (author). 3 refs., 3 tabs., 8 figs

  20. A Growth Curve Analysis of the Course of Dysthymic Disorder: The Effects of Chronic Stress and Moderation by Adverse Parent-Child Relationships and Family History

    Science.gov (United States)

    Dougherty, Lea R.; Klein, Daniel N.; Davila, Joanne

    2004-01-01

    Using mixed effects models, the authors examined the effects of chronic stress, adverse parent-child relationships, and family history on the 7.5-year course of dysthymic disorder. Participants included 97 outpatients with early-onset dysthymia who were assessed with semistructured interviews at baseline and 3 additional times at 30-month…

  1. Attitudinal Ambivalence as a Protective Factor Against Junk Food Advertisements: A Moderated Mediation Model of Behavioral Intention.

    Science.gov (United States)

    Ran, Weina; Yamamoto, Masahiro

    2015-08-01

    This study investigates the role of attitudinal ambivalence in moderating the effects of junk food advertisements on behavioral intentions by tapping different facets of this construct-felt ambivalence, potential ambivalence, and affective-cognitive ambivalence. Results based on an online survey of college students indicate that attention to junk food advertisements has an indirect positive effect on intentions to eat junk food through its positive effect on attitudes toward junk food. A moderated mediation model reveals that this indirect effect of junk food advertisements is weakened as respondents' levels of felt ambivalence increase. This moderating role is not observed for the measures of potential ambivalence and affective-cognitive ambivalence. Implications are discussed for health interventions.

  2. Application of a linked stress release model in Corinth Gulf and Central Ionian Islands (Greece)

    Science.gov (United States)

    Mangira, Ourania; Vasiliadis, Georgios; Papadimitriou, Eleftheria

    2017-06-01

    Spatio-temporal stress changes and interactions between adjacent fault segments consist of the most important component in seismic hazard assessment, as they can alter the occurrence probability of strong earthquake onto these segments. The investigation of the interactions between adjacent areas by means of the linked stress release model is attempted for moderate earthquakes ( M ≥ 5.2) in the Corinth Gulf and the Central Ionian Islands (Greece). The study areas were divided in two subareas, based on seismotectonic criteria. The seismicity of each subarea is investigated by means of a stochastic point process and its behavior is determined by the conditional intensity function, which usually gets an exponential form. A conditional intensity function of Weibull form is used for identifying the most appropriate among the models (simple, independent and linked stress release model) for the interpretation of the earthquake generation process. The appropriateness of the models was decided after evaluation via the Akaike information criterion. Despite the fact that the curves of the conditional intensity functions exhibit similar behavior, the use of the exponential-type conditional intensity function seems to fit better the data.

  3. Comparison of Moderate and High Energy of a Nano-Fractional Radiofrequency Treatment on a Photoaging Hairless Mice Model.

    Science.gov (United States)

    Sun, Wenjia; Zhang, Chengfeng; Zhao, Juemin; Wu, Jiaqiang; Xiang, Leihong

    2018-04-01

    Fractional radiofrequency (FRF) has been widely used in skin rejuvenation. To explore optimal settings, it is important to compare different treatment parameters. This study was designed to compare the effect of moderate-energy and high-energy FRF treatment on a hairless mice model. Fifteen photoaged hairless mice were assigned to 3 groups: control, moderate energy, and high energy. Two treatment sessions (T × 1 and T × 2) were performed at 1-month interval. Transepidermal water loss was measured at baseline, immediately, 1, 2, and 4 weeks after T × 1. Skin samples were harvested before each treatment, 1 and 2 months after T × 2. Neocollagenesis was evaluated by hematoxylin and eosin staining, Masson staining, and immunohistochemistry analysis. Transepidermal water loss of high-energy group was significantly higher than the moderate-energy group (p = .008) immediately after T × 1. Remarkable fibroblast proliferation was observed at 1 month after T × 1, followed by significant dermal thickening, and increase of Type I collagen and Type III collagen. There was no significant difference between 2 energy groups in fibroblast proliferation, dermal thickness, and collagen density. The effect of moderate-energy treatment was comparable with that of high energy in neocollagenesis, whereas moderate energy yielded less damage to skin barrier function.

  4. Stress and Fatigue Life Modeling of Cannon Breech Closures Including Effects of Material Strength and Residual Stress

    National Research Council Canada - National Science Library

    Underwood, John

    2000-01-01

    ...; overload residual stress. Modeling of applied and residual stresses at the location of the fatigue failure site is performed by elastic-plastic finite element analysis using ABAQUS and by solid...

  5. HIV-related stigma and symptoms of post-traumatic stress disorder and depression in HIV-infected individuals: does social support play a mediating or moderating role?

    Science.gov (United States)

    Breet, Elsie; Kagee, Ashraf; Seedat, Soraya

    2014-01-01

    HIV stigma plays a major role in the etiology of psychological distress among persons living with HIV, but may be ameliorated by social support. This cross-sectional study examined whether social support mediates or moderates the relationship between HIV stigma and psychological symptoms. We recruited a convenience sample of 210 individuals living with HIV in three peri-urban communities in the Western Cape, South Africa. People living with HIV and AIDS (PLWHA) completed self-report questionnaires that assessed HIV-related stigma, social support, post-traumatic stress disorder (PTSD) and depression. Product-term regression analyses showed that social support played a mediating role in the relationship between HIV-related stigma and symptoms of PTSD (not depression). Social support did not, however, moderate the relationship between HIV-related stigma and PTSD or depression. The results indicate that perceived HIV-related stigma may decrease PLWHA's perceived level of social support, which in turn may increase PTSD symptoms. Moreover, these findings suggest that despite the protective role of social support, there are other factors that affect the relationship between HIV-related stigma and mental health that hinder the buffering role of social support in this relationship. These findings may have implications for designing and implementing interventions that increase perceived social support and decrease perceived HIV-related stigma, which in turn may decrease symptoms of PTSD among PLWHA.

  6. 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