Does Acute Stress Disorder Predict Posttraumatic Stress Disorder Following Bank Robbery?

ERIC Educational Resources Information Center

Hansen, Maj; Elklit, Ask

2013-01-01

Unfortunately, the number of bank robberies is increasing and little is known about the subsequent risk of posttraumatic stress disorder (PTSD). Several studies have investigated the prediction of PTSD through the presence of acute stress disorder (ASD). However, there have only been a few studies following nonsexual assault. The present study…

Kinetics model of bainitic transformation with stress

NASA Astrophysics Data System (ADS)

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.

Self-harm among Hispanic adolescents: investigating the role of culture-related stressors.

PubMed

Cervantes, Richard C; Goldbach, Jeremy T; Varela, Alberto; Santisteban, Daniel A

2014-11-01

Suicide is the third leading cause of death among adolescents. Research shows Hispanic adolescents report disproportionate rates of both suicidal ideation and attempts. The purpose of the present study was twofold. First, the present study aimed to document the presence of suicidal ideation and self-harm behavior in a large heterogeneous sample of Hispanic adolescents. Second, this study sought to identify specific and unique culturally relevant stressors that were associated with the higher self-reported suicidal thoughts and self-harm among Hispanic males and females separately. Data were collected on 1,651 Hispanic adolescents who completed the Hispanic Stress Inventory-Adolescent Version. Results of both rates and culture-related stressors that associated with the high rates of suicidal ideation are presented. Of the eight subscales measured in the Hispanic Stress Inventory-Adolescent, four subscales were predictive of either suicidal ideation or self-harm. For males, Acculturation Gap Stress was associated with suicidal thoughts and Discrimination Stress was associated with both suicidal thoughts and self-harm behavior. For females, Family Drug Stress was associated with suicidal thoughts. Acculturation Gap Stress, Family Drug Stress, and Immigration Stress were all significantly associated with self-harm behaviors. Findings are discussed as they inform future culturally competent prevention interventions and future research studies. Copyright © 2014 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Educator Stress: Myth or Reality?

ERIC Educational Resources Information Center

Farkas, James P.; Milstein, Mike

Although many researchers conclude that education is a profession marked by high levels of stress or experience of "burnout," this paper contends that educators are more adaptable and hence less stressed than the literature would indicate. The paper surveys literature on educator stress, presents studies indicating low educator stress, and…

Freezing degrees of freedom under stress: kinematic evidence of constrained movement strategies.

PubMed

Higuchi, Takahiro; Imanaka, Kuniyasu; Hatayama, Toshiteru

2002-12-01

The present study investigated the effect of psychological stress imposed on movement kinematics in a computer-simulated batting task involving a backward and forward swing of the forearm. The psychological stress was imposed by a mild electric stimulus following poor performance. Fourteen participants hit a moving ball with a horizontal lever and aimed at a distant target with as much accuracy as possible. The kinematic characteristics appearing under stress were delay of movement initiation, small amplitude of movement and low variability of spatial kinematic events between trials. These features were also found in previous studies in which the experimental task required high accuracy. The characteristic kinematics evident in the present study suggested that the movement strategies adopted by the stressed participants were similar to those that appear under high accuracy demand. Moreover, a correlation analysis between the onset times of kinematic events revealed that temporally consistent movements were reproduced under stress. Taken together, the present findings demonstrated that, under psychological stress, movement strategies tend to shift toward the production of more constrained trajectories, as is seen under conditions of high accuracy demand, even though the difficulty of the task itself does not change. Copyright 2002 Elsevier Science B.V.

Webinar Presentation: Air Pollution, Social and Psychosocial Stress, and Respitory Health in the Southern California Children's Health Study

EPA Pesticide Factsheets

This presentation, Air Pollution, Social and Psychosocial Stress, and Respitory Health in the Southern California Children's Health Study, was given at the NIEHS/EPA Children's Centers 2016 Webinar Series: Exposome held on May 11, 2016.

A Pharmacokinetic Study of the Effects of Stress on Chemical Exposure.

DTIC Science & Technology

2000-03-01

CHEMICAL EXPOSURE THESIS Presented to the Faculty of the Graduate School of Engineering and Management of the Air Force Institute of Technology Air...EFFECTS OF STRESS ON CHEMICAL EXPOSURE THESIS Sierra H. Suhajda, B.S. Lieutenant, USAF Presented to the Faculty of the Graduate School of Engineering ...War Syndrome: Dueling studies focus on stress versus environmental exposures as cause of ills," Chemical and Engineering News, 75: 4-5 (13 January

A Study of H-Reflexes in Subjects with Acute Ankle Inversion Injuries

DTIC Science & Technology

1996-12-09

stress to the injured ankle at heel- strike .(57) Any increased inversion stress by way of joint loading in the presence of compromised joint...the present study, may play a role in decreasing the degree of calcaneal inversion just prior to heel- strike and minimize the stress on the lateral...Presentation: * Significant edema/ecchymosis on lateral and medial aspects of ankle. * Possible pitting edema on forefoot (several days post- injury

Predictors of Parenting Stress among Malaysian Mothers of Children with Down Syndrome

ERIC Educational Resources Information Center

Norizan, A.; Shamsuddin, K.

2010-01-01

Background: Having children with intellectual disability can be stressful for most parents. Currently there are very few studies focusing on parenting stress among mothers of children with Down syndrome (DS) in Asia. The present study examined the level of parenting stress experienced by Malaysian mothers of children with DS and evaluated the…

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

PubMed

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.

The role of eye fixation in memory enhancement under stress - An eye tracking study.

PubMed

Herten, Nadja; Otto, Tobias; Wolf, Oliver T

2017-04-01

In a stressful situation, attention is shifted to potentially relevant stimuli. Recent studies from our laboratory revealed that participants stressed perform superior in a recognition task involving objects of the stressful episode. In order to characterize the role of a stress induced alteration in visual exploration, the present study investigated whether participants experiencing a laboratory social stress situation differ in their fixation from participants of a control group. Further, we aimed at shedding light on the relation of fixation behaviour with obtained memory measures. We randomly assigned 32 male and 31 female participants to a control or a stress condition consisting of the Trier Social Stress Test (TSST), a public speaking paradigm causing social evaluative threat. In an established 'friendly' control condition (f-TSST) participants talk to a friendly committee. During both conditions, the committee members used ten office items (central objects) while another ten objects were present without being used (peripheral objects). Participants wore eye tracking glasses recording their fixations. On the next day, participants performed free recall and recognition tasks involving the objects present the day before. Stressed participants showed enhanced memory for central objects, accompanied by longer fixation times and larger fixation amounts on these objects. Contrasting this, fixation towards the committee faces showed the reversed pattern; here, control participants exhibited longer fixations. Fixation indices and memory measures were, however, not correlated with each other. Psychosocial stress is associated with altered fixation behaviour. Longer fixation on objects related to the stressful situation may reflect enhanced encoding, whereas diminished face fixation suggests gaze avoidance of aversive, socially threatening stimuli. Modified visual exploration should be considered in future stress research, in particular when focussing on memory for a stressful episode. Copyright © 2017 Elsevier Inc. All rights reserved.

Brief, pre-learning stress reduces false memory production and enhances true memory selectively in females.

PubMed

Zoladz, Phillip R; Peters, David M; Kalchik, Andrea E; Hoffman, Mackenzie M; Aufdenkampe, Rachael L; Woelke, Sarah A; Wolters, Nicholas E; Talbot, Jeffery N

2014-04-10

Some of the previous research on stress-memory interactions has suggested that stress increases the production of false memories. However, as accumulating work has shown that the effects of stress on learning and memory depend critically on the timing of the stressor, we hypothesized that brief stress administered immediately before learning would reduce, rather than increase, false memory production. In the present study, participants submerged their dominant hand in a bath of ice cold water (stress) or sat quietly (no stress) for 3 min. Then, participants completed a short-term memory task, the Deese-Roediger-McDermott paradigm, in which they were presented with 10 different lists of semantically related words (e.g., candy, sour, sugar) and, after each list, were tested for their memory of presented words (e.g., candy), non-presented unrelated "distractor" words (e.g., hat), and non-presented semantically related "critical lure" words (e.g., sweet). Stress, overall, significantly reduced the number of critical lures recalled (i.e., false memory) by participants. In addition, stress enhanced memory for the presented words (i.e., true memory) in female, but not male, participants. These findings reveal that stress does not unequivocally enhance false memory production and that the timing of the stressor is an important variable that could mediate such effects. Such results could have important implications for understanding the dependability of eyewitness accounts of events that are observed following stress. Copyright © 2014 Elsevier Inc. All rights reserved.

Elastic and viscoelastic calculations of stresses in sedimentary basins

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

Warpinski, N.R.

This study presents a method for estimating the stress state within reservoirs at depth using a time-history approach for both elastic and viscoelastic rock behavior. Two features of this model are particularly significant for stress calculations. The first is the time-history approach, where we assume that the present in situ stress is a result of the entire history of the rock mass, rather than due only to the present conditions. The model can incorporate: (1) changes in pore pressure due to gas generation; (2) temperature gradients and local thermal episodes; (3) consolidation and diagenesis through time-varying material properties; and (4)more » varying tectonic episodes. The second feature is the use of a new viscoelastic model. Rather than assume a form of the relaxation function, a complete viscoelastic solution is obtained from the elastic solution through the viscoelastic correspondence principal. Simple rate models are then applied to obtain the final rock behavior. Example calculations for some simple cases are presented that show the contribution of individual stress or strain components. Finally, a complete example of the stress history of rocks in the Piceance basin is attempted. This calculation compares favorably with present-day stress data in this location. This model serves as a predictor for natural fracture genesis and expected rock fracturing from the model is compared with actual fractures observed in this region. These results show that most current estimates of in situ stress at depth do not incorporate all of the important mechanisms and a more complete formulation, such as this study, is required for acceptable stress calculations. The method presented here is general and is applicable to any basin having a relatively simple geologic history. 25 refs., 18 figs.« less

STRESS RESPONSE STUDIES USING ANIMAL MODELS

EPA Science Inventory

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.

[The relationship between stress and life-style of students at the Faculty of Medicine of Oporto].

PubMed

Loureiro, Elizabete; McIntyre, Teresa; Mota-Cardoso, Rui; Ferreira, Maria Amélia

2008-01-01

Different studies have demonstrated that there are significant changes in the health and habits/life-style of university students, and it seems that Medical students also reveal a significant vulnerability to the adoption of health risk behaviours. The present study aims to (1) characterize the main sources of academic stress of the Medical School students of the University of Porto as well as the intensity with which they are experienced, (2) investigate the variations in academic stress and psychosocial variables, due to gender, year of course and displacement from home and (3) contribute, for the first time, to the understanding of stress and life-style of medical students in Portugal. The empirical study included a sample of 251 students from all 6 years of the course (160 females and 91 males), evaluated by the following instruments: (1) The Inventory of Sources of Academic Stress in Medical Education (ISASME), and the Portuguese versions of (2) the Brief Personal Survey (BPS), (3) the General Health Questionnaire 12 (GHQ-12), and (4) the Interpersonal Behaviour Survey-Brief (ICIBrief). In terms of overall levels of stress (GHQ-12), a prevalence of 58.2% of clinically significant stress symptoms was found, with the students from the basic cycle and those who are living away from home, presenting higher levels of stress. In terms of life-style, 47% of the students revealed health risk behaviours, with eating habits, physical exercise, alcohol and drug consumption, and body image being the main problem areas. Gender and year of course seem to have a significant influence on the variables studied, being the female students those who present higher levels of academic stress, stress responses (pressure/overload, physical distress, anxiety, anger/frustration, inefficiency, depression and loss of control), and low levels of coping confidence; the students of the basic cycle reveal higher levels of stress in managing their life-style (academic stress), general stress symptoms and stress responses. This study calls attention for the need of preventive intervention with medical students in order to prevent negative consequences of stress and improve their life-style by promoting individual and social resources.

Closed-form analysis of fiber-matrix interface stresses under thermo-mechanical loadings

NASA Technical Reports Server (NTRS)

Naik, Rajiv A.; Crews, John H., Jr.

1992-01-01

Closed form techniques for calculating fiber matrix (FM) interface stresses, using repeating square and diamond regular arrays, were presented for a unidirectional composite under thermo-mechanical loadings. An Airy's stress function micromechanics approach from the literature, developed for calculating overall composite moduli, was extended in the present study to compute FM interface stresses for a unidirectional graphite/epoxy (AS4/3501-6) composite under thermal, longitudinal, transverse, transverse shear, and longitudinal shear loadings. Comparison with finite element results indicate excellent agreement of the FM interface stresses for the square array. Under thermal and longitudinal loading, the square array has the same FM peak stresses as the diamond array. The square array predicted higher stress concentrations under transverse normal and longitudinal shear loadings than the diamond array. Under transverse shear loading, the square array had a higher stress concentration while the diamond array had a higher radial stress concentration. Stress concentration factors under transverse shear and longitudinal shear loadings were very sensitive to fiber volume fraction. The present analysis provides a simple way to calculate accurate FM interface stresses for both the square and diamond array configurations.

The impact of cardiac perception on emotion experience and cognitive performance under mental stress.

PubMed

Kindermann, Nicole K; Werner, Natalie S

2014-12-01

Mental stress evokes several physiological responses such as the acceleration of heart rate, increase of electrodermal activity and the release of adrenaline. Moreover, physiological stress responses interact with emotional and behavioral stress responses. In the present study we provide evidence that viscero-sensory feedback from the heart (cardiac perception) is an important factor modulating emotional and cognitive stress responses. In our study, we compared participants with high versus low cardiac perception using a computerized mental stress task, in which they had to respond to rapidly presented visual and acoustic stimuli. Additionally, we assessed physiological responses (heart rate, skin conductance). Participants high in cardiac perception reported more negative emotions and showed worse task performance under the stressor than participants low in cardiac perception. These results were not moderated by physiological responses. We conclude that cardiac perception modulates stress responses by intensifying negative emotions and by impairing cognitive performance.

Faculty Perception of Stress and Coping Strategies in a Saudi Private University: An Exploratory Study

ERIC Educational Resources Information Center

Iqbal, Adnan; Kokash, Husam

2011-01-01

Teaching profession was once viewed as a "low stress occupation" and they have been envied for tenure, light workloads, flexibility and other perks such as foreign trips for study and conference. However, some recent studies suggest that university faculty is among the most stressed occupational group. The present study was conducted to…

Evaluation of bone insertion level of support teeth in class I mandibular removable partial denture associated with an osseointegrated implant: a study using finite element analysis.

PubMed

Verri, Fellippo Ramos; Pellizzer, Eduardo Piza; Pereira, João Antônio; Zuim, Paulo Renato Junqueira; Santiago Júnior, Joel Ferreira

2011-06-01

: This study evaluated the influence of distal extension removable partial denture associated with implant in cases of different bone level of abutment tooth, using 2D finite element analysis. : Eight hemiarch models were simulated: model A-presenting tooth 33 and distal extension removable partial denture replacing others teeth, using distal rest connection and no bone lost; model B-similar to model A but presenting distal guide plate connection; model C- similar to model A but presenting osseointegrated implant with ERA retention system associated under prosthetic base; model D-similar to model B but presenting osseointegrated implant as described in model C; models E, F, G, and H were similar to models A, B, C, and D but presenting reduced periodontal support around tooth 33. Using ANSYS 9.0 software, the models were loaded vertically with 50 N on each cusp tip. For results, von Mises Stress Maps were plotted. : Maximum stress value was encountered in model G (201.023 MPa). Stress distribution was concentrated on implant and retention system. The implant/removable partial denture association decreases stress levels on alveolar mucosa for all models. : Use of implant and ERA system decreased stress concentrations on supporting structures in all models. Use of distal guide plate decreased stress levels on abutment tooth and cortical and trabecular bone. Tooth apex of models with reduced periodontal support presented increased stress when using distal rest.

STRESS RISK FACTORS AND STRESS-RELATED PATHOLOGY: NEUROPLASTICITY, EPIGENETICS AND ENDOPHENOTYPES

PubMed Central

Radley, Jason J.; Kabbaj, Mohamed; Jacobson, Lauren; Heydendael, Willem; Yehuda, Rachel; Herman, James P.

2013-01-01

This review highlights a symposium on stress risk factors and stress susceptibility, presented at the Neurobiology of Stress workshop in Boulder, Colorado, June 2010. This symposium addressed factors linking stress plasticity and reactivity to stress pathology in animal models and in humans. Dr. Jason Radley discussed studies demonstrating prefrontal cortical neuroplasticity and prefrontal control of hypothalamo-pituitary-adrenocortical axis function in rat, highlighting emerging evidence for a critical role of this region in normal and pathological stress integration. Dr. Mohamed Kabbaj summarized his studies of possible epigenetic mechanisms underlying behavioral differences in rat populations bred for differential stress reactivity. Dr. Lauren Jacobson described studies using a mouse model to explore the diverse actions of antidepressant action in brain, suggesting mechanisms whereby antidepressants may be differentially effective in treating specific depression endophenotypes. Dr. Rachel Yehuda discussed the role of glucocorticoids in post-traumatic stress disorder (PTSD), indicating that low cortisol may be a trait that predisposes the individual to development of the disorder. Furthermore, she presented evidence indicating that traumatic events can have transgenerational impact on cortisol reactivity and development of PTSD symptoms. Together, the symposium highlighted emerging themes regarding the role of brain reorganization, individual differences and epigenetics in determining stress plasticity and pathology. PMID:21848436

A Structural Equation Modeling Approach to the Study of Stress and Psychological Adjustment in Emerging Adults

ERIC Educational Resources Information Center

Asberg, Kia K.; Bowers, Clint; Renk, Kimberly; McKinney, Cliff

2008-01-01

Today's society puts constant demands on the time and resources of all individuals, with the resulting stress promoting a decline in psychological adjustment. Emerging adults are not exempt from this experience, with an alarming number reporting excessive levels of stress and stress-related problems. As a result, the present study addresses the…

The Role of Peer Stress and Pubertal Timing on Symptoms of Psychopathology during Early Adolescence

ERIC Educational Resources Information Center

Sontag, Lisa M.; Graber, Julia A.; Clemans, Katherine H.

2011-01-01

Stress is known to amplify the link between pubertal timing and psychopathology. However, few studies have examined the role of peer stress as a context for this link. The present study examined the interaction between perceived pubertal timing and peer stress on symptoms of psychopathology in early adolescence. The sample consisted of 264…

Experiential avoidance as a moderator of the relationship between anxiety sensitivity and perceived stress.

PubMed

Bardeen, Joseph R; Fergus, Thomas A; Orcutt, Holly K

2013-09-01

Given the significant deleterious effects of stress on psychological and physical well-being, the present two-part study sought to clarify relations among putative vulnerability factors (i.e., anxiety sensitivity, experiential avoidance) for perceived stress. Relations among anxiety sensitivity, experiential avoidance, and perceived stress were examined using a large college student sample (N=400) in Study 1 and were replicated using a large community sample (N=838) in Study 2. As predicted, experiential avoidance moderated the relationship between anxiety sensitivity and perceived stress. Contrary to expectations, simple effects in both studies revealed that anxiety sensitivity shared a significant positive association with perceived stress at low, but not high, levels of experiential avoidance. The moderating role of experiential avoidance was found to be robust to the effects of general distress. Moreover, anxiety sensitivity and experiential avoidance evidenced a differential pattern of relations with perceived stress than was evidenced with related negative affective states (i.e., anxiety and depression). The present results suggest that experiential avoidance appears to be a vulnerability factor of particular importance for understanding the phenomenology of perceived stress. Conceptual and clinical implications are discussed. Copyright © 2013. Published by Elsevier Ltd.

Changes in Stress Perception and Coping during Adolescence: The Role of Situational and Personal Factors

ERIC Educational Resources Information Center

Seiffge-Krenke, Inge; Aunola, Kaisa; Nurmi, Jari-Erik

2009-01-01

The present study investigated the interplay between developmental changes in stress and coping during early and late adolescence. Using a longitudinal design, stress perception and coping styles of 200 adolescents in 7 different stressful situations were investigated. Multilevel piecewise latent growth curve models showed that stress perception…

Continuum Fatigue Damage Modeling for Use in Life Extending Control

NASA Technical Reports Server (NTRS)

Lorenzo, Carl F.

1994-01-01

This paper develops a simplified continuum (continuous wrp to time, stress, etc.) fatigue damage model for use in Life Extending Controls (LEC) studies. The work is based on zero mean stress local strain cyclic damage modeling. New nonlinear explicit equation forms of cyclic damage in terms of stress amplitude are derived to facilitate the continuum modeling. Stress based continuum models are derived. Extension to plastic strain-strain rate models are also presented. Application of these models to LEC applications is considered. Progress toward a nonzero mean stress based continuum model is presented. Also, new nonlinear explicit equation forms in terms of stress amplitude are also derived for this case.

Stress and reproductive failure: past notions, present insights and future directions

PubMed Central

Sheps, Sam; Clara Arck, Petra

2008-01-01

Problem Maternal stress perception is frequently alleged as a cause of infertility, miscarriages, late pregnancy complications or impaired fetal development. The purpose of the present review is to critically assess the biological and epidemiological evidence that considers the plausibility of a stress link to human reproductive failure. Methods All epidemiological studies published between 1980 and 2007 that tested the link between stress exposure and impaired reproductive success in humans were identified. Study outcomes were evaluated on the basis of how associations were predicted, tested and integrated with theories of etiology arising from recent scientific developments in the basic sciences. Further, published evidence arising from basic science research has been assessed in order to provide a mechanistic concept and biological evidence for the link between stress perception and reproductive success. Results Biological evidence points to an immune–endocrine disequilibrium in response to stress and describes a hierarchy of biological mediators involved in a stress trigger to reproductive failure. Epidemiological evidence presents positive correlations between various pregnancy failure outcomes with pre-conception negative life events and elevated daily urinary cortisol. Strikingly, a relatively new conceptual approach integrating the two strands of evidence suggests the programming of stress susceptibility in mother and fetus via a so-called pregnancy stress syndrome. Conclusions An increasing specificity of knowledge is available about the types and impact of biological and social pathways involved in maternal stress responses. The present evidence is sufficient to warrant a reconsideration of conventional views on the etiology of reproductive failure. Physicians and patients will benefit from the adaptation of this integrated evidence to daily clinical practice. PMID:18274890

Memory retrieval of everyday information under stress.

PubMed

Stock, Lisa-Marie; Merz, Christian J

2018-07-01

Psychosocial stress is known to crucially influence learning and memory processes. Several studies have already shown an impairing effect of elevated cortisol concentrations on memory retrieval. These studies mainly used learning material consisting of stimuli with a limited ecological validity. When using material with a social contextual component or with educational relevant material both impairing and enhancing stress effects on memory retrieval could be observed. In line with these latter studies, the present experiment also used material with a higher ecological validity (a coherent text consisting of daily relevant numeric, figural and verbal information). After encoding, retrieval took place 24 h later after exposure to psychosocial stress or a control procedure (20 healthy men per group). The stress group was further subdivided into cortisol responders and non-responders. Results showed a significantly impaired retrieval of everyday information in non-responders compared to responders and controls. Altogether, the present findings indicate the need of an appropriate cortisol response for the successful memory retrieval of everyday information. Thus, the present findings suggest that cortisol increases - contrary to a stressful experience per se - seem to play a protective role for retrieving everyday information. Additionally, it could be speculated that the previously reported impairing stress effects on memory retrieval might depend on the used learning material. Copyright © 2018 Elsevier Inc. All rights reserved.

Stress among School-Going Adolescents in Relation to Psychological Hardiness

ERIC Educational Resources Information Center

Singh, Raminder

2016-01-01

The present study was designed to investigate the stress among school-going adolescents in relation to psychological hardiness and also to study the gender and locale-wise differences in various dimensions and components of stress. The study was conducted over a sample of 200 (100 rural and 100 urban) adolescents studying in 10+1 and 10+2 classes…

Homework Stress: Construct Validation of a Measure

ERIC Educational Resources Information Center

Katz, Idit; Buzukashvili, Tamara; Feingold, Liat

2012-01-01

This article presents 2 studies aimed at validating a measure of stress experienced by children and parents around the issue of homework, applying Benson's program of validation (Benson, 1998). Study 1 provides external validity of the measure by supporting hypothesized relations between stress around homework and students' and parents' positive…

How to Cope with Stress in Special Needs Education? Stress-Inducing Dysfunctional Cognitions of Teacher Students: The Perspective of Professionalisation

ERIC Educational Resources Information Center

Kiel, Ewald; Heimlich, Ulrich; Markowetz, Reinhard; Braun, Annika; Weiß, Sabine

2016-01-01

The goal of the present study is to identify prospective special education teachers (SETs) who may have difficulties in coping with occupational stresses and burdens. International comparative studies show that SETs have a higher level of stress than their colleagues who work in the general school system. Compared with teachers in regular schools,…

A Comparative Study of Stress Profiles in Mothers of Children with Autism and Those of Children with Down's Syndrome

ERIC Educational Resources Information Center

Pisula, Ewa

2007-01-01

Background: The purpose of the present study was to determine the stress in mothers whose children have autism and to compare it with the stress in mothers whose children have Down's syndrome. Method: Fifty mothers whose children had autism (n = 25) or Down's syndrome (n = 25) completed the Questionnaire on Resources and Stress (QRS) and answered…

Reversal of haloperidol induced motor deficits in rats exposed to repeated immobilization stress.

PubMed

Shireen, Erum; Pervez, Sidra; Masroor, Maria; Ali, Wafa Binte; Rais, Qudsia; Khalil, Samira; Tariq, Anum; Haleem, Darakshan Jabeen

2014-09-01

Stress is defined as a non specific response of body to any physiological and psychological demand. Preclinical studies have shown that an uncontrollable stress condition produces neurochemical and behavioral deficits. The present study was conducted to test the hypothesis that a decrease in the responsiveness of somatodendritic 5-hydroxytryptamine (5-HT)-1A receptors following adaptation to stress could attenuate haloperidol induced acute parkinsonian like effect. Results showed that single exposure (2h) to immobilization stress markedly decreased food intake, growth rate and locomotor activity but these stress-induced behavioral deficits were not observed following repeated (2h/day for 5 days) exposure of immobilization stress suggesting behavioral tolerance occurs to similar stress. An important finding of present study is a reversal of haloperidol-induced motor deficits in animals exposed to repeated immobilization stress than respective control animals. It is suggested that stress induced possible desensitization of somatodendritic 5-HT-1A as well as 5-HT-2C receptors could release dopamine system from the inhibitory influence of serotonin. On the other hand, an increase in the effectiveness of postsynaptic 5-HT-1A receptors elicits a direct stimulatory influence on the activity of dopaminergic neuron and is possibly involved in the reversal of haloperidol-induced parkinsonian like symptoms in repeatedly immobilized rats.

Incidental Retrieval of Emotional Contexts in Post-Traumatic Stress Disorder and Depression: An fMRI Study

ERIC Educational Resources Information Center

Whalley, Matthew G.; Rugg, Michael D.; Smith, Adam P. R.; Dolan, Raymond J.; Brewin, Chris R.

2009-01-01

In the present study, we used fMRI to assess patients suffering from post-traumatic stress disorder (PTSD) or depression, and trauma-exposed controls, during an episodic memory retrieval task that included non-trauma-related emotional information. In the study phase of the task neutral pictures were presented in emotional or neutral contexts.…

Parental stress in mothers of children and adolescents with cerebral palsy

PubMed Central

Ribeiro, Maysa Ferreira Martins; Sousa, Ana Luiza Lima; Vandenberghe, Luc; Porto, Celmo Celeno

2014-01-01

Objectives to evaluate parental stress of mothers of children and adolescents with cerebral palsy; to verify whether parental stress undergoes variations according to the level of motor compromise, the child's phase of life, and sociodemographic variables. Method a cross-sectional, descriptive study, with 223 mothers of children and adolescents with cerebral palsy. Results 45.3% of the mothers presented high levels of stress; there were differences in stress between mothers of children with mild and severe motor impairment; mothers of older children were more stressed than mothers of younger children and of adolescents; paid work and leisure activities reduced the stress. Conclusion mothers of children and adolescents with cerebral palsy, whose children present mild to severe motor impairment are vulnerable to parental stress. Paid work and leisure activities were the factors that contributed most to reducing the stress. PMID:25029055

On the determination of growth stress during oxidation of pure zirconium at elevated temperature

NASA Astrophysics Data System (ADS)

Kurpaska, L.; Favergeon, J.; Lahoche, L.; Moulin, G.

2018-07-01

An experimental approach have been proposed to evaluate growth of stress during high temperature oxidation of pure zirconium. The development of stress in the oxide scale has been investigated experimentally in in-situ conditions by combining the Deflection Test in Monofacial Oxidation (DTMO) with Acoustic Emission analysis (AE). Microstructure of the sample were studied by using Scanning Electron Microscopy technique. Oxidation experiments were performed continuously during 24 h at 400 °C and 500 °C in air under normal atmospheric pressure. Taking into account purely elastic behaviour of the material, primary evolution of growth stress developed in the oxide scale during oxidation process have been estimated. Presented study of the Zr/ZrO2 system revealed two opposite phenomena of stress relief when cooling from 400 °C and 500 °C to room temperature. This study is presented as a tool to understand the phenomena of stress evolution in the zirconia layer during isothermal treatment at high temperature and after cooling.

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

PubMed

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

2012-01-01

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

Acoustic Correlates of Emphatic Stress in Central Catalan

ERIC Educational Resources Information Center

Nadeu, Marianna; Hualde, Jose Ignacio

2012-01-01

A common feature of public speech in Catalan is the placement of prominence on lexically unstressed syllables ("emphatic stress"). This paper presents an acoustic study of radio speech data. Instances of emphatic stress were perceptually identified. Within-word comparison between vowels with emphatic stress and vowels with primary lexical stress…

Can Post mTBI Neurological Soft Signs Predict Postconcussive and PTSD Symptoms : A Pilot Study

DTIC Science & Technology

2014-02-01

disorders , including post - traumatic stress disorder ( PTSD ), but they have scarcely been studied in TBI. The present study measured NSS in the...including post - traumatic stress disorder ( PTSD ), but they have scarcely been studied in TBI. The present study measured NSS in the acute aftermath of...Can Post mTBI Neurological Soft Signs Predict Postconcussive and PTSD Symptoms?: A Pilot Study 5a. CONTRACT NUMBER E-Mail:

Effects of stress on alcohol drinking: a review of animal studies

PubMed Central

Lopez, Marcelo F.; Doremus-Fitzwater, Tamara L.

2011-01-01

Rationale While stress is often proposed to play a significant role in influencing alcohol consumption, the relationship between stress and alcohol is complex and poorly understood. Over several decades, stress effects on alcohol drinking have been studied using a variety of animal models and experimental procedures, yet this large body of literature has generally produced equivocal results. Objectives This paper reviews results from animal studies in which alcohol consumption is evaluated under conditions of acute/sub-chronic stress exposure or models of chronic stress exposure. Evidence also is presented indicating that chronic intermittent alcohol exposure serves as a stressor that consequently influences drinking. Results The effects of various acute/sub-chronic stress procedures on alcohol consumption have generally been mixed, but most study outcomes suggest either no effect or decreased alcohol consumption. In contrast, most studies indicate that chronic stress, especially when administered early in development, results in elevated drinking later in adulthood. Chronic alcohol exposure constitutes a potent stressor itself, and models of chronic intermittent alcohol exposure reliably produce escalation of voluntary alcohol consumption. Conclusions A complex and dynamic interplay among a wide array of genetic, biological, and environmental factors govern stress responses, regulation of alcohol drinking, and the circumstances in which stress modulates alcohol consumption. Suggestions for future directions and new approaches are presented that may aid in developing more sensitive and valid animal models that not only better mimic the clinical situation, but also provide greater understanding of mechanisms that underlie the complexity of stress effects on alcohol drinking. PMID:21850445

Stress exposure and sensitivity in the clinical high-risk syndrome: initial findings from the North American Prodrome Longitudinal Study (NAPLS).

PubMed

Trotman, Hanan D; Holtzman, Carrie W; Walker, Elaine F; Addington, Jean M; Bearden, Carrie E; Cadenhead, Kristin S; Cannon, Tyrone D; Cornblatt, Barbara A; Heinssen, Robert K; Mathalon, Daniel H; Tsuang, Ming T; Perkins, Diana O; Seidman, Larry J; Woods, Scott W; McGlashan, Thomas H

2014-12-01

There is inconsistent evidence for increased stress exposure among individuals at clinical high risk (CHR) for psychosis. Yet similar to patients with a diagnosed psychotic illness, the preponderance of evidence suggests that CHR individuals tend to experience stressful life events (LE) and daily hassles (DH) as more subjectively stressful than healthy individuals. The present study utilizes data from the North American Prodrome Longitudinal Study Phase 2 (NAPLS-2) to test the hypotheses that (1) CHR individuals manifest higher self-reported stress in response to both LE and DH when compared to healthy controls (HC), (2) group differences in self-reported stress increase with age, (3) baseline self-reported stress is associated with follow-up clinical status, and (4) there is a sensitization effect of LE on the response to DH. In contrast to some previous research, the present findings indicate that the CHR group (N=314) reported exposure to more LE when compared to the HC group (N=162). As predicted, CHR participants rated events as more stressful, and those who progressed to psychosis reported a greater frequency of LE and greater stress from events compared to those whose prodromal symptoms remitted. There was also some evidence of stress-sensitization; those who experienced more stress from LE rated current DH as more stressful. The results indicate that the "prodromal" phase is a period of heightened stress and stress sensitivity, and elevated cumulative lifetime exposure to stressful events may increase reactions to current stressors. Copyright © 2014 Elsevier B.V. All rights reserved.

Stress Physiology of Lactic Acid Bacteria

PubMed Central

Papadimitriou, Konstantinos; Alegría, Ángel; Bron, Peter A.; de Angelis, Maria; Gobbetti, Marco; Kleerebezem, Michiel; Lemos, José A.; Linares, Daniel M.; Ross, Paul; Stanton, Catherine; Turroni, Francesca; van Sinderen, Douwe; Varmanen, Pekka; Ventura, Marco; Zúñiga, Manuel; Tsakalidou, Effie

2016-01-01

SUMMARY Lactic acid bacteria (LAB) are important starter, commensal, or pathogenic microorganisms. The stress physiology of LAB has been studied in depth for over 2 decades, fueled mostly by the technological implications of LAB robustness in the food industry. Survival of probiotic LAB in the host and the potential relatedness of LAB virulence to their stress resilience have intensified interest in the field. Thus, a wealth of information concerning stress responses exists today for strains as diverse as starter (e.g., Lactococcus lactis), probiotic (e.g., several Lactobacillus spp.), and pathogenic (e.g., Enterococcus and Streptococcus spp.) LAB. Here we present the state of the art for LAB stress behavior. We describe the multitude of stresses that LAB are confronted with, and we present the experimental context used to study the stress responses of LAB, focusing on adaptation, habituation, and cross-protection as well as on self-induced multistress resistance in stationary phase, biofilms, and dormancy. We also consider stress responses at the population and single-cell levels. Subsequently, we concentrate on the stress defense mechanisms that have been reported to date, grouping them according to their direct participation in preserving cell energy, defending macromolecules, and protecting the cell envelope. Stress-induced responses of probiotic LAB and commensal/pathogenic LAB are highlighted separately due to the complexity of the peculiar multistress conditions to which these bacteria are subjected in their hosts. Induction of prophages under environmental stresses is then discussed. Finally, we present systems-based strategies to characterize the “stressome” of LAB and to engineer new food-related and probiotic LAB with improved stress tolerance. PMID:27466284

Analysis of silicon stress/strain relationships

NASA Technical Reports Server (NTRS)

Dillon, O.

1986-01-01

Results are presented for work on stress-strain relationships in silicon ribbon. Calculations of stress fields, dislocation desities, and buckling were made; uniaxial tensile tests were made on silicon at 1150 C; and dislocation motion studies were performed.

Cognitive and Interpersonal Predictors of Stress Generation in Children of Affectively Ill Parents

ERIC Educational Resources Information Center

Shih, Josephine H.; Abela, John R. Z.; Starrs, Claire

2009-01-01

Stress generation is a process in which individuals, through their depressive symptoms, personal characteristics, and/or behaviors, contribute to the occurrence of stressful life events. While this process has been well documented in adults, few studies have examined it in children. The present study examines whether cognitive and interpersonal…

Children's Abstraction and Generalization of English Lexical Stress Patterns

ERIC Educational Resources Information Center

Redford, Melissa A.; Oh, Grace E.

2016-01-01

The current study investigated school-aged children's internalization of the distributional patterns of English lexical stress as a function of vocabulary size. Sixty children (5;3 to 8;3) participated in the study. The children were asked to blend two individually presented, equally stressed syllables to produce disyllabic nonwords with different…

Chronic and Acute Stress, Gender, and Serotonin Transporter Gene-Environment Interactions Predicting Depression Symptoms in Youth

ERIC Educational Resources Information Center

Hammen, Constance; Brennan, Patricia A.; Keenan-Miller, Danielle; Hazel, Nicholas A.; Najman, Jake M.

2010-01-01

Background: Many recent studies of serotonin transporter gene by environment effects predicting depression have used stress assessments with undefined or poor psychometric methods, possibly contributing to wide variation in findings. The present study attempted to distinguish between effects of acute and chronic stress to predict depressive…

A Preliminary Study of Perceived Stress in Adults with Intellectual Disabilities According to Self-Report and Informant Ratings

ERIC Educational Resources Information Center

Lunsky, Yona; Bramston, Paul

2006-01-01

Background: Stress is a major risk factor for mental health problems in individuals with intellectual disabilities, however few studies on stress have been conducted that take into account the perspective of both the person with the disability and the caregiver. The present study evaluated an informant version of the "Lifestress Inventory," and…

Dispositional Mindfulness and Memory Problems: The Role of Perceived Stress and Sleep Quality

PubMed Central

Brisbon, Nicholas M.; Lachman, Margie E.

2016-01-01

There is a growing body of evidence exploring the beneficial effects of mindfulness on stress, sleep quality, and memory, though the mechanisms involved are less certain. The present study explored the roles of perceived stress and sleep quality as potential mediators between dispositional mindfulness and subjective memory problems. Data were from a Boston area subsample of the Midlife in the United States study (MIDUS-II) assessed in 2004–2006, and again approximately one year later (N=299). As expected, higher dispositional mindfulness was associated with lower perceived stress and better sleep quality. There was no direct association found between mindfulness and subjective memory problems, however, there was a significant indirect effect through perceived stress, although not with sleep quality. The present findings suggest that perceived stress may play a mediating role between dispositional mindfulness and subjective memory problems, in that those with higher mindfulness generally report experiencing less stress than those with lower mindfulness, which may be protective of memory problems in everyday life. PMID:28344682

Intraindividual change and variability in daily stress processes: Findings from two measurement-burst diary studies

PubMed Central

Sliwinski, Martin J.; Almeida, David M.; Smyth, Joshua; Stawski, Robert S.

2010-01-01

There is little longitudinal information on aging-related changes in emotional responses to negative events. The present manuscript examined intraindividual change and variability in the within-person coupling of daily stress and negative affect (NA) using data from two-measurement burst daily diary studies. Three main findings emerged. First, average reactivity to daily stress increased longitudinally, and this increase was evident across most the adult lifespan. Second, individual differences in emotional reactivity to daily stress exhibited long-term temporal stability, but this stability was greatest in midlife and decreased in old age. And third, reactivity to daily stress varied reliably within-persons (across-time), with individual exhibiting higher levels of reactivity during times when reporting high levels of global subject stress in previous month. Taken together, the present results emphasize the importance of modeling dynamic psychosocial and aging processes that operate across different time scales for understanding age-related changes in daily stress processes. PMID:20025399

Characteristics of Stress and Suicidal Ideation in the Disclosure of Sexual Orientation among Young French LGB Adults.

PubMed

Charbonnier, Elodie; Dumas, Florence; Chesterman, Adam; Graziani, Pierluigi

2018-02-07

Lesbians, gays, and bisexual people (LGB) present high levels of suicidal ideation. The disclosure of sexual orientation is a stressful experience which presents a high suicide risk. Research has not paid sufficient attention to stress during this disclosure in order to understand suicide among LGB people. The aims of this study were to investigate: (1) the characteristics of stress during this revelation, more precisely cognitive appraisal, emotions, and coping; and (2) associations between these characteristics and suicidal ideation. A total of 200 LGB young adults answered the "Stressful situation assessment questionnaire", focusing on the most stressful disclosure of sexual orientation they have ever experienced. Avoidance coping is a good predictor of suicidal ideation, and mediates the association between primary appraisal (risk "Harm myself and others") and suicidal ideation. Our study illustrates the need to better understand stress during the disclosure of sexual orientation to prevent and care for suicide risk among LGB young adults.

Characteristics of Stress and Suicidal Ideation in the Disclosure of Sexual Orientation among Young French LGB Adults

PubMed Central

Charbonnier, Elodie; Dumas, Florence; Chesterman, Adam; Graziani, Pierluigi

2018-01-01

Background: Lesbians, gays, and bisexual people (LGB) present high levels of suicidal ideation. The disclosure of sexual orientation is a stressful experience which presents a high suicide risk. Research has not paid sufficient attention to stress during this disclosure in order to understand suicide among LGB people. The aims of this study were to investigate: (1) the characteristics of stress during this revelation, more precisely cognitive appraisal, emotions, and coping; and (2) associations between these characteristics and suicidal ideation. Method: A total of 200 LGB young adults answered the “Stressful situation assessment questionnaire”, focusing on the most stressful disclosure of sexual orientation they have ever experienced. Results: Avoidance coping is a good predictor of suicidal ideation, and mediates the association between primary appraisal (risk “Harm myself and others”) and suicidal ideation. Conclusions: Our study illustrates the need to better understand stress during the disclosure of sexual orientation to prevent and care for suicide risk among LGB young adults. PMID:29414915

Dispositional Mindfulness and Memory Problems: The Role of Perceived Stress and Sleep Quality.

PubMed

Brisbon, Nicholas M; Lachman, Margie E

2017-04-01

There is a growing body of evidence exploring the beneficial effects of mindfulness on stress, sleep quality, and memory, though the mechanisms involved are less certain. The present study explored the roles of perceived stress and sleep quality as potential mediators between dispositional mindfulness and subjective memory problems. Data were from a Boston area subsample of the Midlife in the United States study (MIDUS-II) assessed in 2004-2006, and again approximately one year later (N=299). As expected, higher dispositional mindfulness was associated with lower perceived stress and better sleep quality. There was no direct association found between mindfulness and subjective memory problems, however, there was a significant indirect effect through perceived stress, although not with sleep quality. The present findings suggest that perceived stress may play a mediating role between dispositional mindfulness and subjective memory problems, in that those with higher mindfulness generally report experiencing less stress than those with lower mindfulness, which may be protective of memory problems in everyday life.

The protective effect of the Vacha rhizome extract on chronic stress-induced immunodeficiency in rat.

PubMed

Sarjan, H N; Divyashree, S; Yajurvedi, H N

2017-12-01

Chronic stress is an inevitable factor in the modern day society which affects cell mediated as well as humoral immunity. There is a need to prevent stress effects with traditionally used herbs. The present study was undertaken to investigate the immunoprotective effect of Vacha (Acorus calamus L. Acoraceae) rhizome under stressful condition. Soxlet extraction of Vacha rhizome was performed with increasing polarity of solvents, i.e., petroleum ether to ethanol. The extract was concentrated by distilling off the solvent in flash evaporator and dried in desiccators. The benzene extract was found to have anti-stress property in our earlier studies and hence it was used in the present experiment. Extract was administered every day for 4 weeks orally to adult female rats prior to exposure to stress, restraint (1 h) and forced swimming exercise (15 min). Vacha rhizome extract significantly prevented the stress induced reduction in total and differential leukocytes count, immunoglobulin content, bone marrow cellularity and viability, lymphocytes counts in lymphoid organs, islands of white pulp of spleen (ED 50  = 10 mg, p < 0.001) and a significant increase in circulating immune complexes and apoptotic index of lymphoid organs (ED 50  = 10 mg, p < 0.001) compared to controls. The present study clearly indicates that Vacha extract not only prevents stress-induced suppression of immunity and structural involution of lymphoid organs, but also boosts immunity in normal rats. Therefore, it is suggested that Vacha extract administration maintains normal immunity despite the body experiencing stress.

Impact of early life adversity on EMG stress reactivity of the trapezius muscle.

PubMed

Luijcks, Rosan; Vossen, Catherine J; Roggeveen, Suzanne; van Os, Jim; Hermens, Hermie J; Lousberg, Richel

2016-09-01

Human and animal research indicates that exposure to early life adversity increases stress sensitivity later in life. While behavioral markers of adversity-induced stress sensitivity have been suggested, physiological markers remain to be elucidated. It is known that trapezius muscle activity increases during stressful situations. The present study examined to what degree early life adverse events experienced during early childhood (0-11 years) and adolescence (12-17 years) moderate experimentally induced electromyographic (EMG) stress activity of the trapezius muscles, in an experimental setting. In a general population sample (n = 115), an anticipatory stress effect was generated by presenting a single unpredictable and uncontrollable electrical painful stimulus at t = 3 minutes. Subjects were unaware of the precise moment of stimulus delivery and its intensity level. Linear and nonlinear time courses in EMG activity were modeled using multilevel analysis. The study protocol included 2 experimental sessions (t = 0 and t = 6 months) allowing for examination of reliability.Results show that EMG stress reactivity during the stress paradigm was consistently stronger in people with higher levels of early life adverse events; early childhood adversity had a stronger moderating effect than adolescent adversity. The impact of early life adversity on EMG stress reactivity may represent a reliable facet that can be used in both clinical and nonclinical studies.

Fingerprinting stress: Stylolite and calcite twinning paleopiezometry revealing the complexity of progressive stress patterns during folding—The case of the Monte Nero anticline in the Apennines, Italy

NASA Astrophysics Data System (ADS)

Beaudoin, Nicolas; Koehn, Daniel; Lacombe, Olivier; Lecouty, Alexandre; Billi, Andrea; Aharonov, Einat; Parlangeau, Camille

2016-07-01

In this study we show for the first time how quantitative stress estimates can be derived by combining calcite twinning and stylolite roughness stress fingerprinting techniques in a fold-and-thrust belt. First, we present a new method that gives access to stress inversion using tectonic stylolites without access to the stylolite surface and compare results with calcite twin inversion. Second, we use our new approach to present a high-resolution deformation and stress history that affected Meso-Cenozoic limestone strata in the Monte Nero Anticline during its late Miocene-Pliocene growth in the Umbria-Marche Arcuate Ridge (northern Apennines, Italy). In this area an extensive stylolite-joint/vein network developed during layer-parallel shortening (LPS), as well as during and after folding. Stress fingerprinting illustrates how stress in the sedimentary strata did build up prior to folding during LPS. The stress regime oscillated between strike slip and compressional during LPS before ultimately becoming strike slip again during late stage fold tightening. Our case study shows that high-resolution stress fingerprinting is possible and that this novel method can be used to unravel temporal relationships that relate to local variations of regional orogenic stresses. Beyond regional implications, this study validates our approach as a new powerful toolbox to high-resolution stress fingerprinting in basins and orogens combining joint and vein analysis with sedimentary and tectonic stylolite and calcite twin inversion techniques.

The effects of cognitive appraisal of stress on heart rate and task performance.

DOT National Transportation Integrated Search

1968-09-01

In aviation occupations, performance impairment under stress conditions is particularly undesirable. However, individuals may show differing amounts of impairment under stress, and the reasons for these differences are not clear. The present study ex...

Diode step stress testing program for JANTX1N5550

NASA Technical Reports Server (NTRS)

1979-01-01

The effect was studied of power/temperature step stress when applied to the switching diode JANTX1N5550 manufactured by Semtech and Micro Semiconductor. The power/temperature stress tests are presented, and failure analyses are included.

Cardiac damage associated with stress hyperglycaemia and acute coronary syndrome changes according to level of presenting blood glucose.

PubMed

Al Jumaily, Talib; Rose'Meyer, Roselyn B; Sweeny, Amy; Jayasinghe, Rohan

2015-10-01

To determine the prevalence of stress hyperglycaemia in people presenting with acute coronary syndrome (ACS), and the relationships between admission glucose and cardiac damage, cardiovascular mortality and morbidity. In a prospective observational study people presenting with ACS at the Gold Coast Hospital had their admission glucose (AG) level tested to determine stress hyperglycaemia. A range of measurements supplemented this data including troponin levels, category of ACS and major adverse coronary events (MACEs) were obtained through hospital records and patient follow-up post-discharge. One hundred eighty-eight participants were recruited. The prevalence of stress hyperglycaemia in ACS was 44% with 31% having a previous diagnosis of type 2 diabetes and 7.7% had undiagnosed diabetes. The stress hyperglycaemic group had a significantly higher median troponin levels compared to participants with normal blood glucose levels on admission (p<0.05) however the highest presenting glucose group (>15 mmol/L) had troponin levels similar to people presenting with normal blood glucose levels and ACS (p>0.05). Cardiac necrosis as measured by troponin levels is significantly increased in people with ACS and stress hyperglycaemia. This study found that one in four participants presenting with ACS and an admission glucose of >7.0 had no previous diagnosis for diabetes. Consistently ordering HbA1C testing on patients with high AG can enable earlier diagnosis and treatment of diabetes. Copyright © 2015. Published by Elsevier Ireland Ltd.

Approximate Analysis for Interlaminar Stresses in Composite Structures with Thickness Discontinuities

NASA Technical Reports Server (NTRS)

Rose, Cheryl A.; Starnes, James H., Jr.

1996-01-01

An efficient, approximate analysis for calculating complete three-dimensional stress fields near regions of geometric discontinuities in laminated composite structures is presented. An approximate three-dimensional local analysis is used to determine the detailed local response due to far-field stresses obtained from a global two-dimensional analysis. The stress results from the global analysis are used as traction boundary conditions for the local analysis. A generalized plane deformation assumption is made in the local analysis to reduce the solution domain to two dimensions. This assumption allows out-of-plane deformation to occur. The local analysis is based on the principle of minimum complementary energy and uses statically admissible stress functions that have an assumed through-the-thickness distribution. Examples are presented to illustrate the accuracy and computational efficiency of the local analysis. Comparisons of the results of the present local analysis with the corresponding results obtained from a finite element analysis and from an elasticity solution are presented. These results indicate that the present local analysis predicts the stress field accurately. Computer execution-times are also presented. The demonstrated accuracy and computational efficiency of the analysis make it well suited for parametric and design studies.

Plant Abiotic Stress Proteomics: The Major Factors Determining Alterations in Cellular Proteome

PubMed Central

Kosová, Klára; Vítámvás, Pavel; Urban, Milan O.; Prášil, Ilja T.; Renaut, Jenny

2018-01-01

HIGHLIGHTS: Major environmental and genetic factors determining stress-related protein abundance are discussed.Major aspects of protein biological function including protein isoforms and PTMs, cellular localization and protein interactions are discussed.Functional diversity of protein isoforms and PTMs is discussed. Abiotic stresses reveal profound impacts on plant proteomes including alterations in protein relative abundance, cellular localization, post-transcriptional and post-translational modifications (PTMs), protein interactions with other protein partners, and, finally, protein biological functions. The main aim of the present review is to discuss the major factors determining stress-related protein accumulation and their final biological functions. A dynamics of stress response including stress acclimation to altered ambient conditions and recovery after the stress treatment is discussed. The results of proteomic studies aimed at a comparison of stress response in plant genotypes differing in stress adaptability reveal constitutively enhanced levels of several stress-related proteins (protective proteins, chaperones, ROS scavenging- and detoxification-related enzymes) in the tolerant genotypes with respect to the susceptible ones. Tolerant genotypes can efficiently adjust energy metabolism to enhanced needs during stress acclimation. Stress tolerance vs. stress susceptibility are relative terms which can reflect different stress-coping strategies depending on the given stress treatment. The role of differential protein isoforms and PTMs with respect to their biological functions in different physiological constraints (cellular compartments and interacting partners) is discussed. The importance of protein functional studies following high-throughput proteome analyses is presented in a broader context of plant biology. In summary, the manuscript tries to provide an overview of the major factors which have to be considered when interpreting data from proteomic studies on stress-treated plants. PMID:29472941

Job stress factors, stress response, and social support in association with insomnia of Japanese male workers.

PubMed

Nishitani, Naoko; Sakakibara, Hisataka

2010-01-01

The aim of the present study was to examine the relation of insomnia with job stress factors, stress response, and social support. A self-completed questionnaire survey was conducted in 212 male Japanese workers at a synthetic fiber plant. With regard to insomnia, subjects were asked the first 5 of the 8 questions on the Athens Insomnia Scale (AIS). Job stress factors, stress response and social support were assessed using the Job Stress Questionnaire. Multiple regression analyses showed that psychological job stress factors of poor appropriateness of work and high qualitative workload were associated with insomnia. The psychological stress response of depression and physical stress responses were also related with insomnia. Depression was also related to appropriateness of work. The present results showed that insomnia was closely related with the psychological job stress factor of appropriateness of work and the psychological response of depression. These mutual relationships between insomnia and poor mental health need be investigated further.

Stress Within Students: Do Educators Cause and/or Prolong It?

ERIC Educational Resources Information Center

Youngs, Bettie B.

Because studies have shown that educators need to become more aware of the effects of stress upon their students, this guide presents basic information about stress and anxiety in children from infancy to adolescence. Experiences are provided through which students can learn to deal more effectively with stress, together with definitions of the…

College Students Coping with Interpersonal Stress: Examining a Control-Based Model of Coping

ERIC Educational Resources Information Center

Coiro, Mary Jo; Bettis, Alexandra H.; Compas, Bruce E.

2017-01-01

Objective: The ways that college students cope with stress, particularly interpersonal stress, may be a critical factor in determining which students are at risk for impairing mental health disorders. Using a control-based model of coping, the present study examined associations between interpersonal stress, coping strategies, and symptoms.…

The Development, Evaluation, and Validation of a Financial Stress Scale for Undergraduate Students

ERIC Educational Resources Information Center

Northern, Jebediah J.; O'Brien, William H.; Goetz, Paul W.

2010-01-01

Financial stress is commonly experienced among college students and is associated with adverse academic, mental health, and physical health outcomes. Surprisingly, no validated measures of financial stress have been developed for undergraduate populations. The present study was conducted to generate and evaluate a measure of financial stress for…

Sacral Stress Fracture Mimicking Lumbar Radiculopathy in a Mounted Police Officer: Case Report and Literature Review.

PubMed

Bednar, Drew A; Almansoori, Khaled

2015-10-01

Study Design Case report and review of the literature. Objective To present a unique case of L5 radiculopathy caused by a sacral stress fracture without neurologic compression. Methods We present our case and its clinical evolution and review the available literature on similar pathologies. Results Relief of the unusual mechanical loading causing sacral stress fracture led to rapid resolution of radiculopathy. Conclusion L5 radiculopathy can be caused by a sacral stress fracture and can be relieved by simple mechanical treatment of the fracture.

[Assessment of stress in childhood: Children's Daily Stress Inventory (Inventario Infantil de Estresores Cotidiano, IIEC)].

PubMed

Trianes Torres, María Victoria; Blanca Mena, María José; Fernández Baena, Francisco J; Escobar Espejo, Milagros; Maldonado Montero, Enrique F; Muñoz Sánchez, Angela María

2009-11-01

The present study introduces the Children's Daily Stress Inventory (Inventario Infantil de Estresores Cotidianos, IIEC) as a measure that assesses daily stress in primary school children. The inventory was applied to a sample of 1094 primary school students. The final version includes 25 dichotomic items covering the areas of health, school/peers, and family. The score is obtained by adding the total of positive answers. Analyses of items, reliability and several external pieces of evidence of validity based on relations with other variables are presented. The results show adequate psychometric properties for the assessment of daily stress in children.

Perceived stress and bruxism in university students.

PubMed

Cavallo, Pierpaolo; Carpinelli, Luna; Savarese, Giulia

2016-12-21

Many studies have shown the correlation between bruxism and stress that affects the quality of life of university students. The present study highlights this correlation-for the first time-in a group of university students in Italy. We have investigated the prevalence of awake and asleep bruxism and its correlation with perceived stress in a group of 278 Italian undergraduate students (117 M). A self report questionnaire was constructed using a socio-demographic test, the Perceived Stress Scale (PSS) and the item n. 8 of the Fonseca Questionnaire for presence of bruxism. The perceived stress score using PSS-10 scale was 32.2 (SD 4.6, 95% CL 31.6-32.7) for all the subjects, with significant gender difference: M = 31.2 and F = 32.9 (P = 0.0019). The prevalence for awake bruxism was 37.9% (F = 40.8%; M = 34.2%,), while for sleep bruxism was 31.8% (F = 33.3%; M = 29.1%), both without significant gender difference. A positive correlation, with significant concordance and dependence, between stress score and awake bruxism was present for male students only. University students showed higher bruxism and stress levels compared to the general population, with higher stress for females, but, even if female students show higher stress, a correlation between stress and bruxism exists only for male gender. Further studies should be performed.

Neutron residual stress measurements on rail sections for different production conditions

DOT National Transportation Integrated Search

2004-11-13

Rail sectioning with subsequent neutron diffraction experiments has been used to assess residual stresses in the rails. In this study we present the results of neutron stress : measurements performed at the NIST Center for Neutron Research (NCNR) on ...

Anger, Stress Proliferation, and Depressed Mood among Parents of Children with ASD: A Longitudinal Replication

ERIC Educational Resources Information Center

Benson, Paul R.; Karlof, Kristie L.

2009-01-01

"Stress proliferation" (the tendency for stressors to create additional stressors) has been suggested as an important contributor to depression among caregivers. The present study utilized longitudinal data from 90 parents of children with ASD to replicate and extend a prior cross-sectional study on stress proliferation by Benson (J Autism Develop…

Longitudinal Analysis of Chinese High School Student's Stress in School and Academic Achievement

ERIC Educational Resources Information Center

Liu, Yangyang; Lu, Zuhong

2011-01-01

In previous research, few studies have examined the effects of adolescents' stress in school on the change rates of their academic achievement. In the present study, we seek to examine the longitudinal relationships between adolescents' stress in school and the change rates of their academic achievement. The results indicated that for those whose…

Building on Strengths and Resilience: Leisure as a Stress Survival Strategy

ERIC Educational Resources Information Center

Iwasaki, Yoshitaka; MacTavish, Jennifer; MacKay, Kelly

2005-01-01

Exploring the ways in which leisure contributes to managing, relieving, or counteracting stress has become an increasingly popular area of study in recent years. Findings from a multi-year study of stress and coping among diverse residents of a western Canadian city are reported in this paper. In particular, the key findings presented are specific…

Occupational stress and health-related quality of life among public sector bank employees: A cross-sectional study in Mysore, Karnataka, India.

PubMed

Malamardi, Sowmya N; Kamath, Ramachandra; Tiwari, Rajnarayan; Nair, Binu Valsalakumari Sreekumaran; Chandrasekaran, Varalakshmi; Phadnis, Sameer

2015-01-01

Occupational morbidities have been estimated to cause an economic loss up to 10-20% of the gross national product of a country. It is an important cause of occupational morbidity and decreased quality of life (QOL) for the workers. The aim of the present study is to assess the level of occupational stress and its association with the QOL among the public sector bank employees. The present study was conducted among employees of public sector banks in Mysore district, Karnataka, India. A cross-sectional study design was used for the study. Job stress was measured by using occupational stress index (OSI) scale questionnaire and health-related QOL was measured using the short form 12 (SF-12) questionnaire. The sample size estimated for the study was 526 and cluster random sampling technique was used. Chi-square test was used to find the association between the study variables and level of stress. Multiple linear regression model was used to find the determinants of health-related QOL among the study subjects. The total number of the study subjects was 546 out of which 57% were males and 43% were females. The proportion of study subjects reporting to be current smokers was 4.2% and almost all study subjects reported occasional alcohol consumption. The mean physical component summary (PCS) score and mental component summary (MCS) using the original United States standardization were 47.90 and 48.30, respectively. The individuals with mild stress scored higher in both PCS and MCS than the individuals who had moderate to severe stress levels. There was significant association of health related quality of life with the age of the respondent,presence of at least one morbidity and level of stress with health-related QOL. This study has shown an association of occupational stress with the QOL. There is a need for interventions aimed at mitigating the occupational stress among employees of the banking sector.

Stress Physiology of Lactic Acid Bacteria.

PubMed

Papadimitriou, Konstantinos; Alegría, Ángel; Bron, Peter A; de Angelis, Maria; Gobbetti, Marco; Kleerebezem, Michiel; Lemos, José A; Linares, Daniel M; Ross, Paul; Stanton, Catherine; Turroni, Francesca; van Sinderen, Douwe; Varmanen, Pekka; Ventura, Marco; Zúñiga, Manuel; Tsakalidou, Effie; Kok, Jan

2016-09-01

Lactic acid bacteria (LAB) are important starter, commensal, or pathogenic microorganisms. The stress physiology of LAB has been studied in depth for over 2 decades, fueled mostly by the technological implications of LAB robustness in the food industry. Survival of probiotic LAB in the host and the potential relatedness of LAB virulence to their stress resilience have intensified interest in the field. Thus, a wealth of information concerning stress responses exists today for strains as diverse as starter (e.g., Lactococcus lactis), probiotic (e.g., several Lactobacillus spp.), and pathogenic (e.g., Enterococcus and Streptococcus spp.) LAB. Here we present the state of the art for LAB stress behavior. We describe the multitude of stresses that LAB are confronted with, and we present the experimental context used to study the stress responses of LAB, focusing on adaptation, habituation, and cross-protection as well as on self-induced multistress resistance in stationary phase, biofilms, and dormancy. We also consider stress responses at the population and single-cell levels. Subsequently, we concentrate on the stress defense mechanisms that have been reported to date, grouping them according to their direct participation in preserving cell energy, defending macromolecules, and protecting the cell envelope. Stress-induced responses of probiotic LAB and commensal/pathogenic LAB are highlighted separately due to the complexity of the peculiar multistress conditions to which these bacteria are subjected in their hosts. Induction of prophages under environmental stresses is then discussed. Finally, we present systems-based strategies to characterize the "stressome" of LAB and to engineer new food-related and probiotic LAB with improved stress tolerance. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Academic stress levels were positively associated with sweet food consumption among Korean high-school students.

PubMed

Kim, Yeonsoo; Yang, Hye Young; Kim, Ae-Jung; Lim, Yunsook

2013-01-01

The objectives of the present study were to identify the association among levels of persistent academic stress, appetite, and dietary habits and to determine the specific types of sweet foods consumed by Korean high-school students according to their academic stress levels. The study participants included 333 high-school students in the 10th to 12th grades in Kyunggi Province, Korea. The level of academic stress was scored with a 75-item academic stress scale and was categorized as high, medium, or low. A food-frequency questionnaire was used to measure the sugar intake from sweet foods. Korean high-school students with a high academic stress level had larger meals than the other students. Compared with students with low academic stress, the students with high academic stress had a higher frequency of sugar intake from the following food types: confectionaries, candies and chocolates, breads, and flavored milk. Moreover, compared with students with low academic stress, the students with high academic stress had a higher total intake of sugar from the following food types: confectionaries, candies, chocolates, flavored milk, traditional Korean beverages, and spicy, sweet, and fried rice cakes. Unhealthy stress-related food choices may compromise high-school students' health and contribute to their morbidity. The findings of the present study could be used to help nutritionists develop effective strategies for nutritional education and counseling to improve adolescent health. Copyright © 2013 Elsevier Inc. All rights reserved.

Gender differences in responses to cues presented in the natural environment of cigarette smokers.

PubMed

Wray, Jennifer M; Gray, Kevin M; McClure, Erin A; Carpenter, Matthew J; Tiffany, Stephen T; Saladin, Michael E

2015-04-01

Although the evidence is mixed, female smokers appear to have more difficulty quitting smoking than male smokers. Craving, stress, and negative affect have been hypothesized as potential factors underlying gender differences in quit rates. In the current study, the cue-reactivity paradigm was used to assess craving, stress, and negative affect in response to cues presented in the natural environment of cigarette smokers using ecological momentary assessment. Seventy-six daily smokers (42% female) responded to photographs (smoking, stress, and neutral) presented 4 times per day on an iPhone over the course of 2 weeks. Both smoking and stress cues elicited stronger cigarette craving and stress responses compared to neutral cues. Compared with males, females reported higher levels of post-stress cue craving, stress, and negative affect, but response to smoking cues did not differ by gender. Findings from this project were largely consistent with results from laboratory-based research and extend previous work by measuring response to cues in the natural environment of cigarette smokers. This study extends previous cue reactivity ecological momentary assessment research by using a new platform and by measuring response to stress cues outside of the laboratory. Findings from this project highlight the importance of addressing coping in response to stress cues in clinical settings, especially when working with female smokers. © The Author 2015. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Maternal Stress during Pregnancy Predicts Cognitive Ability and Fearfulness in Infancy

ERIC Educational Resources Information Center

Bergman, Kristin; Sarkar, Pampa; O'Connor, Thomas G.; Modi, Neena; Glover, Vivette

2007-01-01

The effects of prenatal stress on cognition and behavioral fearfulness in infants are studied. The findings suggest that mechanisms by which mental development and fearfulness are affected by prenatal stress are different and do not present a consistent relation.

Does Maternal Prenatal Stress Adversely Affect the Child's Learning and Memory at Age Six?

ERIC Educational Resources Information Center

Gutteling, Barbara M.; de Weerth, Carolina; Zandbelt, Noortje; Mulder, Eduard J. H.; Visser, Gerard H. A.; Buitelaar, Jan K.

2006-01-01

Prenatal maternal stress has been shown to affect postnatal development in animals and humans. In animals, the morphology and function of the offspring's hippocampus is negatively affected by prenatal maternal stress. The present study prospectively investigated the influence of prenatal maternal stress on learning and memory of 112 children (50…

EFL Teachers' Stress and Job Satisfaction: What Contribution Can Teacher Education Make?

ERIC Educational Resources Information Center

Sadeghi, Karim; Sa'adatpourvahid, Morteza

2016-01-01

The present study was conducted to find out the level of job satisfaction and stress among Iranian EFL teachers. More precisely, an attempt was made to investigate the main sources of EFL teachers' stress, their level of satisfaction with the job and the relationship between occupational stress and instructors' age, marital status and tenure.…

The Acquisition of English Lexical Stress by Chinese-Speaking Learners: An OT Account

ERIC Educational Resources Information Center

Yuan, Man; Cheng, Wei

2017-01-01

Lexical stress is an important contributor to foreign accent as well as intelligibility of second language (L2) speech. The present study intends to find out to what extent Chinese-speaking learners whose native language has less evident stress can acquire English lexical stress. A production test was administered to nine advanced Chinese learners…

Dual Minority Stress and Asian American Gay Men's Psychological Distress

ERIC Educational Resources Information Center

Chen, Yung-Chi; Tryon, Georgiana Shick

2012-01-01

The present study investigated the direct and additive effects of racial minority stress and sexual minority stress on the psychological well-being among a community sample of 139 Asian American gay men. Self-esteem was tested to see whether it moderated or mediated the effects of perceived dual minority stress on psychological distress. Results…

Personality as a Resource in Stress Resistance: The Hardy Type.

ERIC Educational Resources Information Center

Maddi, Salvatore R.

The notion that life stresses and personality have an interactive role in illness is part of the wisdom of the ages. Most past research has studied either life stresses or personality. A model for understanding health/illness status is presented that includes stressful life events and the resistance resources of personality, social supports,…

Cumulative life stress in chronic fatigue syndrome.

PubMed

Nater, Urs M; Maloney, Elizabeth; Heim, Christine; Reeves, William C

2011-09-30

We studied the impact of cumulative life stress on CFS in a population-based study. We found that exposure to stressors was significantly more common in persons with CFS compared to NF controls; those with CFS reported experiencing significantly higher levels of psychological distress. Also, post-traumatic stress disorder was significantly more common in people with CFS. These results not only corroborate findings from other studies but, importantly, extend those by: a) measuring a comprehensive spectrum of stress variables, b) for the first time presenting data on stress in a population-based study, thus minimizing the effects of recruitment bias, and c) diagnosing CFS by means of standardized, validated scales, thus allowing replication and extension of our findings. Stress may be an important factor in the pathophysiology of CFS. Consequently, future studies should provide a more detailed understanding of the processes that lead from stress to CFS using longitudinal designs. Published by Elsevier Ireland Ltd.

PA03.15. Study on relation of Prakriti with academic stress in school going children

PubMed Central

Madhukar, Atika; Kumari, O Nisha; Kumar, Abhimanyu

2013-01-01

Purpose: Fast pace of life, highly competitive school environment and parental pressure brought child life cumbersome and full of stress and anxiety. These lead to maladjustment in different spheres of life such as home, social, health, emotion and educational problems. Testing or examination can produce anxiety in students, and can lower student's self–esteem, and increase their fear of failure. School–related stress is the most prevalent, untreated cause of academic failure in schools. Prevalence rates of anxiety disorders in community samples, based on clinical interviews vary between 21–29%. In this present study a relation between prakriti and academic stress was assessed for the proper management of academic stress in this competitive world. Method: Children, aged between 10–16 years, for the present study were screened out from OPD of National Institute of Ayurveda, Jaipur and from various schools, situated in Jaipur by survey method. Result: Maximum numbers of patients with Academic stress belonged to vata–pitta parkriti. Conclusion: Vata Prakriti predisposes the child to develop academic stress as compared to pitta and kapha prakriti and multiple approach includoa ing medhyadrug, shirodhara and prakriti based Ayurvedic counseling is very much effective to manage the condition of Academic stress.

Salt geometry influence on present-day stress orientations in the Nile Delta: Insights from numerical modeling

NASA Astrophysics Data System (ADS)

Eckert, Andreas; Zhang, Weicheng

2016-02-01

The offshore Nile Delta displays sharply contrasting orientations of the maximum horizontal stress, SH, in regions above Messinian evaporites (suprasalt) and regions below Messinian evaporites (subsalt). Published stress orientation data predominantly show margin-normal suprasalt SH orientations but a margin-parallel subsalt SH orientation. While these data sets provide the first major evidence that evaporite sequences can act as mechanical detachment horizons, the cause for the stress orientation contrast remains unclear. In this study, 3D finite element analysis is used to investigate the causes for stress re-orientation based on two different hypotheses. The modeling study evaluates the influence of different likely salt geometries and whether stress reorientations are the result of basal drag forces induced by gravitational gliding or whether they represent localized variations due to mechanical property contrasts. The modeling results show that when salt is present as a continuous layer, gravitational gliding occurs and basal drag forces induced in the suprasalt layers result in the margin-normal principal stress becoming the maximum horizontal stress. With the margin-normal stress increase being confined to the suprasalt layers, the salt acts as a mechanical detachment horizon, resulting in different SH orientations in the suprasalt compared to the subsalt layers. When salt is present as isolated bodies localized stress variations occur due to the mechanical property contrasts imposed by the salt, also resulting in different SH orientations in the suprasalt compared to the subsalt layers. The modeling results provide additional quantitative evidence to confirm the role of evaporite sequences as mechanical detachment horizons.

Elastic And Plastic Deformations In Butt Welds

NASA Technical Reports Server (NTRS)

Verderaime, V.

1992-01-01

Report presents study of mathematical modeling of stresses and strains, reaching beyond limits of elasticity, in bars and plates. Study oriented toward development of capability to predict stresses and resulting elastic and plastic strains in butt welds.

Surgeons' and surgical trainees' acute stress in real operations or simulation: A systematic review.

PubMed

Georgiou, Konstantinos; Larentzakis, Andreas; Papavassiliou, Athanasios G

2017-12-01

Acute stress in surgery is ubiquitous and has an immediate impact on surgical performance and patient safety. Surgeons react with several coping strategies; however, they recognise the necessity of formal stress management training. Thus, stress assessment is a direct need. Surgical simulation is a validated standardised training milieu designed to replicate real-life situations. It replicates stress, prevents biases, and provides objective metrics. The complexity of stress mechanisms makes stress measurement difficult to quantify and interpret. This systematic review aims to identify studies that have used acute stress estimation measurements in surgeons or surgical trainees during real operations or surgical simulation, and to collectively present the rationale of these tools, with special emphasis in salivary markers. A search strategy was implemented to retrieve relevant articles from MEDLINE and SCOPUS databases. The 738 articles retrieved were reviewed for further evaluation according to the predetermined inclusion/exclusion criteria. Thirty-three studies were included in this systematic review. The methods for acute stress assessment varied greatly among studies with the non-invasive techniques being the most commonly used. Subjective and objective tests for surgeons' acute stress assessment are being presented. There is a broad spectrum of acute mental stress assessment tools in the surgical field and simulation and salivary biomarkers have recently gained popularity. There is a need to maintain a consistent methodology in future research, towards a deeper understanding of acute stress in the surgical field. Copyright © 2017 Royal College of Surgeons of Edinburgh (Scottish charity number SC005317) and Royal College of Surgeons in Ireland. Published by Elsevier Ltd. All rights reserved.

Acute psycho-social stress does not disrupt item-method directed forgetting, emotional stimulus content does.

PubMed

Zwissler, Bastian; Koessler, Susanne; Engler, Harald; Schedlowski, Manfred; Kissler, Johanna

2011-03-01

It has been shown that stress affects episodic memory in general, but knowledge about stress effects on memory control processes such as directed forgetting is sparse. Whereas in previous studies item-method directed forgetting was found to be altered in post-traumatic stress disorder patients and abolished for highly arousing negative pictorial stimuli in students, no study so far has investigated the effects of experimentally induced psycho-social stress on this task or examined the role of positive picture stimuli. In the present study, 41 participants performed an item-method directed forgetting experiment while being exposed either to a psychosocial laboratory stressor, the Trier Social Stress Test (TSST), or a cognitively challenging but non-stressful control condition. Neutral and positive pictures were presented as stimuli. As predicted, salivary cortisol level as a biological marker of the human stress response increased only in the TSST group. Still, both groups showed directed forgetting. However, emotional content of the employed stimuli affected memory control: Directed forgetting was intact for neutral pictures whereas it was attenuated for positive ones. This attenuation was primarily due to selective rehearsal improving discrimination accuracy for neutral, but not positive, to-be-remembered items. Results suggest that acute experimentally induced stress does not alter item-method directed forgetting while emotional stimulus content does. Copyright © 2011 Elsevier Inc. All rights reserved.

Impact of early life adversity on EMG stress reactivity of the trapezius muscle

PubMed Central

Luijcks, Rosan; Vossen, Catherine J.; Roggeveen, Suzanne; van Os, Jim; Hermens, Hermie J.; Lousberg, Richel

2016-01-01

Abstract Human and animal research indicates that exposure to early life adversity increases stress sensitivity later in life. While behavioral markers of adversity-induced stress sensitivity have been suggested, physiological markers remain to be elucidated. It is known that trapezius muscle activity increases during stressful situations. The present study examined to what degree early life adverse events experienced during early childhood (0–11 years) and adolescence (12–17 years) moderate experimentally induced electromyographic (EMG) stress activity of the trapezius muscles, in an experimental setting. In a general population sample (n = 115), an anticipatory stress effect was generated by presenting a single unpredictable and uncontrollable electrical painful stimulus at t = 3 minutes. Subjects were unaware of the precise moment of stimulus delivery and its intensity level. Linear and nonlinear time courses in EMG activity were modeled using multilevel analysis. The study protocol included 2 experimental sessions (t = 0 and t = 6 months) allowing for examination of reliability. Results show that EMG stress reactivity during the stress paradigm was consistently stronger in people with higher levels of early life adverse events; early childhood adversity had a stronger moderating effect than adolescent adversity. The impact of early life adversity on EMG stress reactivity may represent a reliable facet that can be used in both clinical and nonclinical studies. PMID:27684800

Chronic high fat, high cholesterol supplementation decreases 18 kDa Translocator Protein binding capacity in association with increased oxidative stress in rat liver and aorta.

PubMed

Dimitrova-Shumkovska, Jasmina; Veenman, Leo; Ristoski, Trpe; Leschiner, Svetlana; Gavish, Moshe

2010-03-01

It is well known that high fat and high cholesterol levels present a contributing factor to pathologies including fatty liver and atherosclerosis. Oxidative stress is also considered to play a role in these pathologies. The 18 kDa Translocator Protein (TSPO), formerly known as the peripheral-type benzodiazepine receptor, is known to be involved in cholesterol metabolism, oxidative stress, and cardiovascular pathology. We applied a high fat high cholesterol atherogenic (HFHC) diet to rats to study correlations between cardiovascular and liver pathology, oxidative stress, and TSPO expression in the liver and the cardiovascular system. This study corroborates the presence of increased oxidative stress markers and decreased anti-oxidants in liver and aorta. In addition, it appeared that induction of oxidative stress in the liver and aorta by atherogenic HFHC diet was accompanied by a reduction in TSPO binding density in both these tissues. Our data suggest that involvement of TSPO in oxidative stress and ROS generation, as reported in other studies, may also take part in atherogenesis as induced by HFHC diet. Presently, it is not clear whether this TSPO response is compensatory for the stress induced by HFHC diet or is a participant in the induction of oxidative stress. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

The influence of family stress and conflict on depressive symptoms among working married women: A longitudinal study.

PubMed

Ju, Yeong Jun; Park, Eun-Cheol; Ju, Hyun-Jun; Lee, Sang Ah; Lee, Joo Eun; Kim, Woorim; Chun, Sung-Youn; Kim, Tae Hyun

2018-03-01

In the present study, researchers examined the association between depressive symptoms and family stress and conflict from multiple roles, along with the combined effect of family stress and family-work conflict. We used data from the 2008-2012 Korean Welfare Panel Study, consisting of 4,663 baseline participants. We measured depressive symptoms using the 11-item Center for Epidemiologic Studies Depression Scale. There was a significant relationship between depressive symptoms and family stress and conflict among working married women. With regard to the combined analysis, working married women who reported both family stress and family-work conflict exhibited the highest odds of depressive symptoms.

The Roles of Perceived Stress, Coping Styles, and Perceived Social Support on the Alcohol Consumption among American College Students

ERIC Educational Resources Information Center

Wynn, Jesse

2017-01-01

The intention of this study was to better understand how certain aspects in a college student's life (i.e., perceived stress, styles of coping, and social support) or how combinations of these variables may contribute to higher levels of alcohol consumption. The present study examined the relationship between perceived stress, functional coping…

Job Stress and Coping Strategies among Early Childhood Teachers in Central Taiwan

ERIC Educational Resources Information Center

Hung, Chih-Lun

2012-01-01

The purpose of this study was to explore the association between job stress and coping strategies in early childhood teachers in Central Taiwan. A quantitative approach was utilized, and data were collected from 314 participants. The results of the present study suggest that (1) early childhood teachers believed that their job stress was due to a…

Fluid shear stress and tumor metastasis

PubMed Central

Huang, Qiong; Hu, Xingbin; He, Wanming; Zhao, Yang; Hao, Shihui; Wu, Qijing; Li, Shaowei; Zhang, Shuyi; Shi, Min

2018-01-01

The tumor microenvironment (TME) is a key factor regulating tumor cell invasion and metastasis. The effects of biochemical factors such as stromal cells, immune cells, and cytokines have been previously investigated. Owing to restrictions by the natural barrier between physical and biochemical disciplines, the role of physical factors in tumorigenesis is unclear. However, with the emergence of interdisciplinary mechanobiology and continuous advancements therein in the past 30 years, studies on the effect of physical properties such as hardness or shear stress on tumorigenesis and tumor progression are constantly renewing our understanding of mechanotransduction mechanisms. Shear stress, induced by liquid flow, is known to actively participate in proliferation, apoptosis, invasion, and metastasis of tumor cells. The present review discusses the progress and achievements in studies on tumor fluid microenvironment in recent years, especially fluid shear stress, on tumor metastasis, and presents directions for future study.

Discrimination and Acculturative Stress among First-Generation Dominicans

ERIC Educational Resources Information Center

Dawson, Beverly Araujo; Panchanadeswaran, Subadra

2010-01-01

The present study examined the relationship between discriminatory experiences and acculturative stress levels among a sample of 283 Dominican immigrants. Findings from a linear regression analysis revealed that experiences of daily racial discrimination and major racist events were significant predictors of acculturative stress after controlling…

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

PubMed

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.

Reduced Cortisol Output during Public Speaking Stress in Ostracized Women.

PubMed

Weik, Ulrike; Ruhweza, Jennifer; Deinzer, Renate

2017-01-01

Ostracism (being excluded or ignored) is experienced as unpleasant and distressing. In previous studies, an immediate pre-stress experience of ostracism induced by Cyberball, a virtual ball-tossing game, was found to inhibit cortisol reactivity to public speaking stress in female students. The present study examines whether the effect will persist when a 15-min time gap between the Cyberball experience and subsequent psychological stress is introduced. N = 84 women were randomly assigned to Cyberball ostracism vs. inclusion. 15 min after playing Cyberball, all women were subjected to public speaking stress. Salivary cortisol and mood were repeatedly assessed during the course of the experiment. These are the main findings of the study: Repeated measures ANCOVA revealed that public speaking stress resulted in a significant increase of cortisol in both groups (inclusion vs. ostracism). However, cortisol levels were significantly lower in the ostracism group. In earlier studies when Cyberball was played immediately before public speaking stress, the cortisol response to public speaking was completely suppressed in ostracized women. By introducing a waiting period between Cyberball and public speaking stress in the present study, the main effect of an ostracism induced reduction of cortisol remained, although both groups showed an increase of cortisol as a response to public speaking. These results again suggest that the experience of ostracism might inhibit hypothalamic-pituitary-adrenal (HPA) axis activity, thereby confirming previous results. The formerly observed total suppression of HPA axis responsiveness to public speaking, however, seems to be a rather short-term effect.

Reduced Cortisol Output during Public Speaking Stress in Ostracized Women

PubMed Central

Weik, Ulrike; Ruhweza, Jennifer; Deinzer, Renate

2017-01-01

Ostracism (being excluded or ignored) is experienced as unpleasant and distressing. In previous studies, an immediate pre-stress experience of ostracism induced by Cyberball, a virtual ball-tossing game, was found to inhibit cortisol reactivity to public speaking stress in female students. The present study examines whether the effect will persist when a 15-min time gap between the Cyberball experience and subsequent psychological stress is introduced. N = 84 women were randomly assigned to Cyberball ostracism vs. inclusion. 15 min after playing Cyberball, all women were subjected to public speaking stress. Salivary cortisol and mood were repeatedly assessed during the course of the experiment. These are the main findings of the study: Repeated measures ANCOVA revealed that public speaking stress resulted in a significant increase of cortisol in both groups (inclusion vs. ostracism). However, cortisol levels were significantly lower in the ostracism group. In earlier studies when Cyberball was played immediately before public speaking stress, the cortisol response to public speaking was completely suppressed in ostracized women. By introducing a waiting period between Cyberball and public speaking stress in the present study, the main effect of an ostracism induced reduction of cortisol remained, although both groups showed an increase of cortisol as a response to public speaking. These results again suggest that the experience of ostracism might inhibit hypothalamic-pituitary-adrenal (HPA) axis activity, thereby confirming previous results. The formerly observed total suppression of HPA axis responsiveness to public speaking, however, seems to be a rather short-term effect. PMID:28228738

[Stress among nurses: an examination of salivary cortisol levels on work and day off].

PubMed

Pires da Rocha, Maria Cecília; Figueiredo de Martino, Milva Maria; Grassi-Kassisse, Dora Maria; Luiz de Souza, Aglécio

2013-10-01

The present study evaluates the use of salivary cortisol concentration as a physiological index of the stress level among nurses on their work day and day off and correlates it with the questionnaire used to measure occupational stress in nurses (Inventário de Estresse em Enfermeiros - IEE). This is a comparative, cross-sectional descriptive study in which sociodemographic data, IEE results and salivary cortisol levels were used. Fifty-seven nurses participated in the study (80.7% females and a mean age of 37.1 years old). The IEE average score was 124.5. The average cortisol level was 564.1 ng/m on work day and 354.1 ng/mL on day off. Nurses who had double workdays presented high values of salivary cortisol during the work day (638.1 ng/mL). In conclusion, salivary cortisol identified the nurses' stress level, and differences were found between a work day and day off. On the nurses' day off, their salivary cortisol levels and stress scores were lower.

Effect of simulated transport stress on the rat small intestine: A morphological and gene expression study.

PubMed

Wan, Changrong; Yin, Peng; Xu, Xiaolong; Liu, Mingjiang; He, Shasha; Song, Shixiu; Liu, Fenghua; Xu, Jianqin

2014-04-01

The present study investigated the effects of simulated transport stress on morphology and gene expression in the small intestine of laboratory rats. Sprague Dawley rats were subjected to 35°C and 0.1×g on a constant temperature shaker for physiological, biochemical, morphological and microarray analysis before and after treatment. The treatment induced obvious stress responses with significant decreases in body weight (P<0.01), increases in rectal temperature, serum corticosterone (CORT), serum glucose (GLU), creatine kinase (CK) and lactate dehydrogenase (LDH) levels (P<0.01), as well as expression of Hsp27/70/90 mRNA (P<0.05; P<0.01). The rat jejunum was severely damaged and apoptotic after mimicking transport stress, which may mainly be related to cell death, oxidation reduction and hormone imbalance determined by microarray analysis. The bioinformatics analysis from the present study would provide insight into the potential mechanisms underlying transport stress-induced injury in the rat small intestine. Copyright © 2014 Elsevier Ltd. All rights reserved.

[Basic thoughts on psychopharmacological interventions through psychotherapy of severe forms of post-traumatic stress disorder: a case study].

PubMed

Joksimovic, Ljiljana; Wöller, Wolfgang; Kunzke, Dieter

2013-01-01

The present paper focuses on clinical issues concerning the psychopharmacological treatment of severe forms of post-traumatic stress disorder (PTSD).Using a case study, we discuss problems in this field against the background of psychodynamic and psychotraumatological theories. We also present strategies for the appropriate use of psychotropic drugs in the psychotherapy of PTSD.

Stress, coping and burnout among Intensive Care Unit nursing staff: associated factors.

PubMed

Andolhe, Rafaela; Barbosa, Ricardo Luis; Oliveira, Elaine Machado de; Costa, Ana Lúcia Siqueira; Padilha, Katia Grillo

2015-02-01

Objective To investigate emotional stress, coping and burnout among nursing staff and their association with biosocial factors and characteristics of work in Intensive Care Units (ICU). Method This was a cross-sectional study, conducted in eight ICUs at a teaching hospital in the city of São Paulo, Brazil, in October 2012. Biosocial data and information about the professionals' work was gathered, and they were given the Scale of Occupational Stress, Scale of Occupational Coping, List of Signs and Symptoms of Stress and the Maslach Burnout Inventory. Results The study sample consisted of 287 subjects, predominately women, with partners and children. Most professionals presented moderate stress levels and control as a coping strategy (74.47% and 79.93%, respectively), and burnout was present among 12.54%. Factors associated with stress were related to working conditions. The most prevalent protective factors were having a partner, working in the clinical ICU and liking work, while adequate amount of sleep was a protective factor for burnout. Conclusion Control of the working environment and adequate sleep are decisive and protective factors in dealing with situations of occupational stress.

Nonlocal approach to the analysis of the stress distribution in granular systems. I. Theoretical framework

NASA Astrophysics Data System (ADS)

Kenkre, V. M.; Scott, J. E.; Pease, E. A.; Hurd, A. J.

1998-05-01

A theoretical framework for the analysis of the stress distribution in granular materials is presented. It makes use of a transformation of the vertical spatial coordinate into a formal time variable and the subsequent study of a generally non-Markoffian, i.e., memory-possessing (nonlocal) propagation equation. Previous treatments are obtained as particular cases corresponding to, respectively, wavelike and diffusive limits of the general evolution. Calculations are presented for stress propagation in bounded and unbounded media. They can be used to obtain desired features such as a prescribed stress distribution within the compact.

Experimental Study on the Anisotropic Stress-Strain Behavior of Polycrystalline Ni-Mn-Ga in Directional Solidification

NASA Astrophysics Data System (ADS)

Teng, Yao; Shi, Tao; Zhu, Yuping; Li, Zongbin; Deng, Tao; Bai, Guonan

2016-03-01

A polycrystalline Ni-Mn-Ga ferromagnetic shape memory alloy produced by directional solidification is the subject of this research paper. The compressive stress-strain curves of the material for different cutting angles to the solidification direction are tested. The martensite Young's modulus, macroscopic reorientation strain, and phase transition critical stress are analyzed experimentally. The results show that mechanical behaviors in the loading-unloading cycle of the material present nonlinear and anisotropic characteristics, which are all closely related to the material's orientation to the solidification direction. The martensite Young's modulus, macroscopic reorientation strain, and phase transition critical stress achieve maximum values in the solidification direction. A 50° orientation to the solidification direction is the cut-off direction of the mechanical properties, where the martensite Young's modulus and reorientation start critical stress reach minimum values. The present study is expected to provide sound guidance for practical applications.

Comparison of three acute stress models for simulating the pathophysiology of stress-related mucosal disease.

PubMed

Saxena, Bhagawati; Singh, Sanjay

2017-05-30

Stress-related mucosal disease (SRMD) is highly prevalent in intensive care patients leading to increasing treatment cost and mortality. SRMD is a disease elusive of ideal treatment. Evaluation of drugs is very pertinent for the efficient and safe treatment of SRMD. It relies mainly on in vivo screening models. There are various stress models, and till date, none of them is validated for simulating the SRMD pathophysiology. The present study aims to choose the best model, which reproduce pathophysiology of SRMD, among previously established stress models. This study evaluates ulcer index, hexosamine content, microvascular permeability, and gastric content in three acute stress models (cold-restraint, restraint, and water immersion restraint). Macroscopic pictures of the ulcerogenic stomach explain that in contrast to other models, cold-restraint stress (CRS) exposure produced marked ulcers on the fundic area of the stomach. Results of the present study depicted that each stress model significantly increased ulcer index, microvascular permeability and decreased hexosamine level, however, the maximum in the case of CRS-exposed rats. Total acidity and pH of the gastric content remains unchanged in all the stress models. On the contrary, the gastric volume significantly decreased only in case of CRS, while unchanged in other stress models. The overall results revealed that the CRS resembles the pathophysiology of SRMD closely. It is the best and feasible model among all the models to evaluate drugs for the treatment of SRMD.

Testing a Moderated Mediation Model of Mindfulness, Psychosocial Stress, and Alcohol Use among African American Smokers

PubMed Central

Cano, Miguel A.; Heppner, Whitney L.; Stewart, Diana W.; Correa-Fernández, Virmarie; Vidrine, Jennifer Irvin; Li, Yisheng; Cinciripini, Paul M.; Ahluwalia, Jasjit S.; Wetter, David W.

2014-01-01

Mindfulness-based strategies have received empirical support for improving coping with stress and reducing alcohol use. The present study presents a moderated mediation model to explain how mindfulness might promote healthier drinking patterns. This model posits that mindfulness reduces perceived stress, leading to less alcohol use, and also weakens the linkage between stress and alcohol use. African American smokers (N = 399, 51% female, Mage = 42) completed measures of dispositional mindfulness, perceived stress, quantity of alcohol use, frequency of binge drinking, and alcohol use disorder symptoms. Participants with higher levels of dispositional mindfulness reported less psychosocial stress and lower alcohol use on all measures. Furthermore, mindfulness moderated the relationship between perceived stress and quantity of alcohol consumption. Specifically, higher perceived stress was associated with increased alcohol use among participants low, but not high, in mindfulness. Mindfulness may be one strategy to reduce perceived stress and associated alcohol use among African American smokers. PMID:25848408

Memantine effects on liver and adrenal gland of rats exposed to cold stress

PubMed Central

2011-01-01

Background Memantine attenuates heart stress due cold stress, however, no study focused its effects on liver and adrenal gland. We evaluated its effects on lipid depletion in adrenal gland and glycogen depletion in liver of rats exposed to cold stress. Methods Male rats divided into 4 groups: 1)Control (CON); 2)Memantine (MEM); 3)Induced cold stress (IH) and; 4)Induced cold stress memantine (IHF). Memantine were administrated by gavage (20 mg/kg/day) during eight days. Cold stress were performed during 4 hours once at - 8°C. Lipid and glycogen depletion were presented as its intensity levels. Results Rats exposed to cold stress presented the highest glycogen (p < 0.001) and lipid depletion (p < 0.001) in liver and adrenal gland, respectively. We noted that memantine significantly reduced lipid depletion in adrenal gland and glycogen depletion in liver. Conclusion Memantine prevented glycogen depletion in liver and lipid depletion in adrenal gland of rats under a cold stress condition. PMID:21255456

The second International Symposium on Fungal Stress: ISFUS.

PubMed

Alder-Rangel, Alene; Bailão, Alexandre M; da Cunha, Anderson F; Soares, Célia M A; Wang, Chengshu; Bonatto, Diego; Dadachova, Ekaterina; Hakalehto, Elias; Eleutherio, Elis C A; Fernandes, Éverton K K; Gadd, Geoffrey M; Braus, Gerhard H; Braga, Gilberto U L; Goldman, Gustavo H; Malavazi, Iran; Hallsworth, John E; Takemoto, Jon Y; Fuller, Kevin K; Selbmann, Laura; Corrochano, Luis M; von Zeska Kress, Marcia R; Bertolini, Maria Célia; Schmoll, Monika; Pedrini, Nicolás; Loera, Octavio; Finlay, Roger D; Peralta, Rosane M; Rangel, Drauzio E N

2018-06-01

The topic of 'fungal stress' is central to many important disciplines, including medical mycology, chronobiology, plant and insect pathology, industrial microbiology, material sciences, and astrobiology. The International Symposium on Fungal Stress (ISFUS) brought together researchers, who study fungal stress in a variety of fields. The second ISFUS was held in May 8-11 2017 in Goiania, Goiás, Brazil and hosted by the Instituto de Patologia Tropical e Saúde Pública at the Universidade Federal de Goiás. It was supported by grants from CAPES and FAPEG. Twenty-seven speakers from 15 countries presented their research related to fungal stress biology. The Symposium was divided into seven topics: 1. Fungal biology in extreme environments; 2. Stress mechanisms and responses in fungi: molecular biology, biochemistry, biophysics, and cellular biology; 3. Fungal photobiology in the context of stress; 4. Role of stress in fungal pathogenesis; 5. Fungal stress and bioremediation; 6. Fungal stress in agriculture and forestry; and 7. Fungal stress in industrial applications. This article provides an overview of the science presented and discussed at ISFUS-2017. Copyright © 2017 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Police Work Absence: An Analysis of Stress and Resiliency

PubMed Central

Fekedulegn, Desta; Hartley, Tara A.; Andrew, Michael E.; Charles, Luenda; Tinney-Zara, Cathy A.; Burchfiel, Cecil M.

2015-01-01

Police work is a high stress occupation and stress has been implicated in work absence. The present study examined (1) associations between specific types of police stress and work absences, (2) distinctions between “voluntary” (1-day) and “involuntary” (> 3-days) absences; and (3) the modifying effect of resiliency. Officers (n=337) from the Buffalo Cardio-Metabolic Occupational Police Stress study were included in the present study. The sample was 72% male, 77% Caucasian, 73% married, and 75% patrol officers. Mean age was 41 years (SD=6.4). Measures included: the Spielberger Police Stress Survey, 1-year payroll absence data, and the Dispositional Resilience Scale. The negative binomial regression was used to estimate rate ratios (RR) of 1-day and >3-days work absences for increasing stress scores. Models were adjusted for age, race/ethnicity, rank, smoking status, alcohol intake, and sleep duration. For one-unit increase in stress scores, the covariate adjusted RRs for one-day work absences were: total stress score (RR=1.19, 95% CI: 1.04–1.36); administrative stress (RR=1.52, 95% CI: 1.05–2.18); physical/psychological stress (RR=1.54, 95% CI: 1.14–2.07); and lack of support (RR=1.75, 95% CI: 1.01–3.05). Results suggest that officers were more likely to take voluntary 1-day absences due to specific types of stress at work. When the entire sample was considered, there was no significant association between police specific stress and episodes of work absence lasting at least three consecutive days. Hardy individuals, including those with high scores on the challenge sub-score, may use 1-day absences as a positive coping strategy. PMID:26709384

Mechanical Twinning and Microstructures in Experimentally Stressed Quartzite

NASA Astrophysics Data System (ADS)

Minor, A.; Sintubin, M.; Wenk, H. R.; Rybacki, E.

2015-12-01

Since Dauphiné twins in quartz have been identified as a stress-related intracrystalline microstructure, several electron backscatter diffraction (EBSD) studies revealed that Dauphiné twins are present in naturally deformed quartz-bearing rocks in a wide range of tectono-metamorphic conditions. EBSD studies on experimentally stressed quartzite showed that crystals with particular crystallographic orientations contain many Dauphiné twin boundaries, while neighboring crystals with different orientations are largely free of twin boundaries. To understand the relationship between stress direction and orientation of Dauphiné twinned quartz crystals, a detailed EBSD study was performed on experimentally stressed quartzite samples and compared with an undeformed reference sample. We stressed 4 cylindrical samples in triaxial compression in a Paterson type gas deformation apparatus at GFZ Potsdam. Experimental conditions were 300MPa confining pressure, 500°C temperature and axial stresses of 145MPa, 250MPa and 460MPa for about 30 hours, resulting in a minor strain <0.04%. EBSD scans were obtained with a Zeiss Evo scanning electron microscope and TSL software at UC Berkeley. The EBSD maps show that Dauphiné twinning is present in the starting material as well as in experimentally stressed samples. Pole figures of the bulk orientation of the reference sample compared with stressed samples show a significant difference regarding the distribution for the r and z directions. The reference sample shows an indistinct maximum for r and z, whereas the stressed samples show a maximum for r poles and a minimum for z poles in the axial stress direction. EBSD scans of the reference and stressed samples were further analyzed manually to identify the orientations of single grains, which are free of twin boundaries and those, which contain twin boundaries. This analysis aims to quantify the relationship of crystal orientation and stress magnitude to initiate mechanical twinning.

Ixpantepec Nieves Mixtec Word Prosody

NASA Astrophysics Data System (ADS)

Carroll, Lucien Serapio

This dissertation presents a phonological description and acoustic analysis of the word prosody of Ixpantepec Nieves Mixtec, which involves both a complex tone system and a default stress system. The analysis of Nieves Mixtec word prosody is complicated by a close association between morphological structure and prosodic structure, and by the interactions between word prosody and phonation type, which has both contrastive and non-contrastive roles in the phonology. I contextualize these systems within the phonology of Nieves Mixtec as a whole, within the literature on other Mixtec varieties, and within the literature on cross-linguistic prosodic typology. The literature on prosodic typology indicates that stress is necessarily defined abstractly, as structured prominence realized differently in each language. Descriptions of stress in other Mixtec varieties widely report default stress on the initial syllable of the canonical bimoraic root, though some descriptions suggest final stress or mobile stress. I first present phonological evidence---from distributional restrictions, phonological processes, and loanword adaptation---that Nieves Mixtec word prosody does involve a stress system, based on trochaic feet aligned to the root. I then present an acoustic study comparing stressed syllables to unstressed syllables, for ten potential acoustic correlates of stress. The results indicate that the acoustic correlates of stress in Nieves Mixtec include segmental duration, intensity and periodicity. Building on analyses of other Mixtec tone systems, I show that the distribution of tone and the tone processes in Nieves Mixtec support an analysis in which morae may bear H, M or L tone, where M tone is underlyingly unspecified, and each morpheme may sponsor a final +H or +L floating tone. Bimoraic roots thus host up to two linked tones and one floating tone, while monomoraic clitics host just one linked tone and one floating tone, and tonal morphemes are limited to a single floating tone. I then present three studies describing the acoustic realization of tone and comparing the realization of tone in different prosodic types. The findings of these studies include a strong directional asymmetry in tonal coarticulation, increased duration at the word or phrase boundary, phonation differences among the tone categories, and F0 differences between the glottalization categories.

Stress among Black Women in a South African Township: The Protective Role of Religion

ERIC Educational Resources Information Center

Copeland-Linder, Nikeea

2006-01-01

Communities that have been exposed to high levels of stress and where religiosity is salient are ideal contexts in which to examine the role of religion in stress processes. The present study examines the protective function of religiosity among Black women in a South African township. The women (N = 172) were interviewed about sources of stress,…

Stress in Portuguese Middle School Transition: A Multilevel Analysis.

PubMed

Coelho, Vítor Alexandre; Romão, Ana Maria

2016-09-23

Transition from elementary to middle school is commonly seen as a period of stress, impacting students' school adjustment. The present longitudinal study aimed to analyze the difference in stress levels between the end of 4th grade and 5th grade, while also analyzing gender differences and 5th grade retention. Two hundred fifty-eight 4th grade students (M age = 9.55; SD = 0.77) from six Portuguese public schools, from the municipality of Torres Vedras, participated in this study. Self-report questionnaires were administered at the end of the 4th and 5th grades, and 5th grade school records were also collected. Results showed that 5th graders present higher levels of Academic Stress (d = .29) and Teacher/Rules Stress (d = .28). Girls had a greater increase of Peer-related Stress with the transition (p < .01). Students who were retained at the end of 5th grade showed higher increases of Teacher/Rules Stress (p < .05). Intervention programs that aim to support the transition from elementary to middle school are needed, in order to reduce the increase of stress levels at 5th grade and to promote a better school adjustment in the first year of middle school.

Assessing Daily Stress Processes in Social Surveys by Combining Stressor Exposure and Salivary Cortisol

PubMed Central

Almeida, David M.; McGonagle, Katherine; King, Heather

2010-01-01

This paper presents a research method for assessing stress and mental health in ongoing population-based social surveys that combines self-reports of naturally occurring daily stressors with a primary marker of stress physiology, salivary cortisol. We first discuss the relevance of stress processes to mental health and introduce a model for examining daily stress processes, which highlights multiple components of daily stressor exposure. A primary aim of this approach is to capture variability across stressful situations, between persons of different groups, or within persons over a period of time. Next, we describe how the assessment of diurnal salivary cortisol is a promising approach to examining naturally occurring stress physiology in large social surveys. We then present findings from the National Study of Daily Experiences (a substudy of the Midlife in the United States Study) that document the feasibility and reliability of the collection of daily stressors and salivary diurnal cortisol and provide examples of research findings linking stressor exposure to diurnal cortisol. The final portion of the paper describes ways that this approach can leverage the strengths of various features of longitudinal social surveys to extend research on stress and mental health. PMID:20183906

Stressful Segregation Housing and Psychosocial Vulnerability in Prison Suicide Ideators

ERIC Educational Resources Information Center

Bonner, Ronald L.

2006-01-01

Psychosocially vulnerable prisoners under stressful conditions of confinement are ill prepared to cope and at risk for developing suicide intention. The present study examined the relationships of depression, hopelessness, reasons for living, mental health problem history, suicide attempt lethality history, and stressful segregation housing with…

Stress analysis of rotating propellers subject to forced excitations

NASA Astrophysics Data System (ADS)

Akgun, Ulas

Turbine blades experience vibrations due to the flow disturbances. These vibrations are the leading cause for fatigue failure in turbine blades. This thesis presents the finite element analysis methods to estimate the maximum vibrational stresses of rotating structures under forced excitation. The presentation included starts with the derived equations of motion for vibration of rotating beams using energy methods under the Euler Bernoulli beam assumptions. The nonlinear large displacement formulation captures the centrifugal stiffening and gyroscopic effects. The weak form of the equations and their finite element discretization are shown. The methods implemented were used for normal modes analyses and forced vibration analyses of rotating beam structures. The prediction of peak stresses under simultaneous multi-mode excitation show that the maximum vibrational stresses estimated using the linear superposition of the stresses can greatly overestimate the stresses if the phase information due to damping (physical and gyroscopic effects) are neglected. The last section of this thesis also presents the results of a practical study that involves finite element analysis and redesign of a composite propeller.

Stressful life events and depression symptoms: the effect of childhood emotional abuse on stress reactivity.

PubMed

Shapero, Benjamin G; Black, Shimrit K; Liu, Richard T; Klugman, Joshua; Bender, Rachel E; Abramson, Lyn Y; Alloy, Lauren B

2014-03-01

Stressful life events are associated with an increase in depressive symptoms and the onset of major depression. Importantly, research has shown that the role of stress changes over the course of depression. The present study extends the current literature by examining the effects of early life stress on emotional reactivity to current stressors. In a multiwave study (N = 281, mean age = 18.76; 68% female), we investigated the proximal changes that occur in depressive symptoms when individuals are faced with life stress and whether a history of childhood emotional abuse moderates this relationship. Results support the stress sensitivity hypothesis for early emotional abuse history. Individuals with greater childhood emotional abuse severity experienced greater increases in depressive symptoms when confronted with current dependent stressors, controlling for childhood physical and sexual abuse. This study highlights the importance of emotional abuse as an indicator for reactivity to stressful life events. © 2013 Wiley Periodicals, Inc.

Sex differences in stress-related psychiatric disorders: neurobiological perspectives.

PubMed

Bangasser, Debra A; Valentino, Rita J

2014-08-01

Stress is associated with the onset and severity of several psychiatric disorders that occur more frequently in women than men, including posttraumatic stress disorder (PTSD) and depression. Patients with these disorders present with dysregulation of several stress response systems, including the neuroendocrine response to stress, corticolimbic responses to negatively valenced stimuli, and hyperarousal. Thus, sex differences within their underlying circuitry may explain sex biases in disease prevalence. This review describes clinical studies that identify sex differences within the activity of these circuits, as well as preclinical studies that demonstrate cellular and molecular sex differences in stress responses systems. These studies reveal sex differences from the molecular to the systems level that increase endocrine, emotional, and arousal responses to stress in females. Exploring these sex differences is critical because this research can reveal the neurobiological underpinnings of vulnerability to stress-related psychiatric disorders and guide the development of novel pharmacotherapies. Copyright © 2014 Elsevier Inc. All rights reserved.

Sex Differences in Stress-Related Psychiatric Disorders: Neurobiological Perspectives

PubMed Central

Bangasser, Debra A.; Valentino, Rita J.

2014-01-01

Stress is associated with the onset and severity of several psychiatric disorders that occur more frequently in women than men, including posttraumatic stress disorder (PTSD) and depression. Patients with these disorders present with dysregulation of several stress response systems, including the neuroendocrine response to stress, corticolimbic responses to negatively valenced stimuli, and hyperarousal. Thus, sex differences within their underlying circuitry may explain sex biases in disease prevalence. This review describes clinical studies that identify sex differences within the activity of these circuits, as well as preclinical studies that demonstrate cellular and molecular sex differences in stress responses systems. These studies reveal sex differences from the molecular to the systems level that increase endocrine, emotional, and arousal responses to stress in females. Exploring these sex differences is critical because this research can reveal the neurobiological underpinnings of vulnerability to stress-related psychiatric disorders and guide the development of novel pharmacotherapies. PMID:24726661

Normative and counter-normative stress messages and symptom reporting: implications for health promotion and a methodological artefact for stress research.

PubMed

Ferguson, Eamonn; Lawrence, Claire

2013-05-01

There is increasing use of counter-normative health messages (i.e., evidence-based health information about cause-effect relationships that run counter to shared normative beliefs, e.g., stress can lead to personal growth). The current studies examine the effect of normative and counter-normative messages about stress on levels of symptom reporting. Predictions are derived from reactance, social comparison, and self-enhancement theories. Two studies focus on the development of the messages, and two experimental studies examine the effect of manipulating normative and counter-normative messages on symptom reports. The final study controls for mere-measurement effects and explores the role of stress process variables (appraisals and coping). Exposure to a normative message (stress causes ill health) results in reduced symptom reporting compared to a counter-normative message (stress provides challenge, growth, and development) and control groups. The results suggest that people may use symptom reporting strategically to indicate coping. Based on the argument that beliefs about stress and health are stored as mental models, the theoretical associations derived from stress theory are only observed when a normative message is presented. Counter-normative stress messages may carry no tangible benefits compared to normative messages. Some stress research may suffer from inherent methodological bias when normative information is provided in information and consent sheets. Statement of contribution What is already known on this subject? At present, nothing is known about counter-normative health messages, despite the fact that they are becoming widely used as a public intervention. What does this study add? A clear operational definition of counter-normative messages. A test of three competing theories for counter-normative messages that focus of the stress-symptom link. Demonstrating for the first time, that in the domain of stress and health, counter-normative messages are at best ineffective. Demonstrating for the first time that only when the stress-coping-symptom links are made explicit do the theoretical associations observed in the literature emerge. This may be a potential methodological artefact in stress research that needs to be controlled. © 2013 The British Psychological Society.

Safety of a rapid diagnostic protocol with accelerated stress testing.

PubMed

Soremekun, Olan A; Hamedani, Azita; Shofer, Frances S; O'Conor, Katie J; Svenson, James; Hollander, Judd E

2014-02-01

Most patients at low to intermediate risk for an acute coronary syndrome (ACS) receive a 12- to 24-hour "rule out." Recently, trials have found that a coronary computed tomographic angiography-based strategy is more efficient. If stress testing were performed within the same time frame as coronary computed tomographic angiography, the 2 strategies would be more similar. We tested the hypothesis that stress testing can safely be performed within several hours of presentation. We performed a retrospective cohort study of patients presenting to a university hospital from January 1, 2009, to December 31, 2011, with potential ACS. Patients placed in a clinical pathway that performed stress testing after 2 negative troponin values 2 hours apart were included. We excluded patients with ST-elevation myocardial infarction or with an elevated initial troponin. The main outcome was safety of immediate stress testing defined as the absence of death or acute myocardial infarction (defined as elevated troponin within 24 hours after the test). A total of 856 patients who presented with potential ACS were enrolled in the clinical pathway and included in this study. Patients had a median age of 55.0 (interquartile range, 48-62) years. Chest pain was the chief concern in 86%, and pain was present on arrival in 73% of the patients. There were no complications observed during the stress test. There were 0 deaths (95% confidence interval, 0%-0.46%) and 4 acute myocardial infarctions within 24 hours (0.5%; 95% confidence interval, 0.14%-1.27%). The peak troponins were small (0.06, 0.07, 0.07, and 0.19 ng/mL). Patients who present to the ED with potential ACS can safely undergo a rapid diagnostic protocol with stress testing. © 2013.

Bruxism affects stress responses in stressed rats.

PubMed

Sato, Chikatoshi; Sato, Sadao; Takashina, Hirofumi; Ishii, Hidenori; Onozuka, Minoru; Sasaguri, Kenichi

2010-04-01

It has been proposed that suppression of stress-related emotional responses leads to the simultaneous activation of both sympathetic and parasympathetic divisions of the autonomic nervous system (ANS) and that the expression of these emotional states has a protective effect against ulcerogenesis. In the present study, we investigated whether stress-induced bruxism activity (SBA) has a physiological effect of on the stress-induced changes of the stomach, thymus, and spleen as well as blood leukocytes, cortisol, and adrenaline. This study demonstrated that SBA attenuated the stress-induced ulcer genesis as well as degenerative changes of thymus and spleen. SBA also attenuated increases of adrenaline, cortisol, and neutrophils in the blood. In conclusion, expression of aggression through SBA during stress exposure attenuates both stress-induced ANS response, including gastric ulcer formation.

Stress-Constrained Structural Topology Optimization with Design-Dependent Loads

NASA Astrophysics Data System (ADS)

Lee, Edmund

Topology optimization is commonly used to distribute a given amount of material to obtain the stiffest structure, with predefined fixed loads. The present work investigates the result of applying stress constraints to topology optimization, for problems with design-depending loading, such as self-weight and pressure. In order to apply pressure loading, a material boundary identification scheme is proposed, iteratively connecting points of equal density. In previous research, design-dependent loading problems have been limited to compliance minimization. The present study employs a more practical approach by minimizing mass subject to failure constraints, and uses a stress relaxation technique to avoid stress constraint singularities. The results show that these design dependent loading problems may converge to a local minimum when stress constraints are enforced. Comparisons between compliance minimization solutions and stress-constrained solutions are also given. The resulting topologies of these two solutions are usually vastly different, demonstrating the need for stress-constrained topology optimization.

Academic Stress as a Health Measure and Its Relationship to Patterns of Emotion in Collectivist and Individualist Cultures: Similarities and Differences

ERIC Educational Resources Information Center

Kormi-Nouri, Reza; MacDonald, Shane; Farahani, Mohammad-Naghy; Trost, Kari; Shokri, Omid

2015-01-01

The present study investigates academic stress in two different cultures, the Iranian as a collectivist culture, and the Swedish as an individualist culture. A total of 616 university students (312 Iranian and 304 Swedish) participated in the study. The results show that Swedish students experience more academic stress than Iranian students.…

A preliminary examination of railroad dispatcher workload, stress, and fatigue

DOT National Transportation Integrated Search

2001-05-01

This report presents the methods, findings and recommendations from a field study that examined the sources and levels of railroad dispatcher workload, stress, and fatigue. The study was initiated in response to concerns raised by two Federal Railroa...

Nonlinear temperature dependent failure analysis of finite width composite laminates

NASA Technical Reports Server (NTRS)

Nagarkar, A. P.; Herakovich, C. T.

1979-01-01

A quasi-three dimensional, nonlinear elastic finite element stress analysis of finite width composite laminates including curing stresses is presented. Cross-ply, angle-ply, and two quasi-isotropic graphite/epoxy laminates are studied. Curing stresses are calculated using temperature dependent elastic properties that are input as percent retention curves, and stresses due to mechanical loading in the form of an axial strain are calculated using tangent modulii obtained by Ramberg-Osgood parameters. It is shown that curing stresses and stresses due to tensile loading are significant as edge effects in all types of laminate studies. The tensor polynomial failure criterion is used to predict the initiation of failure. The mode of failure is predicted by examining individual stress contributions to the tensor polynomial.

Teacher Stress--An Ongoing Problem That Needs Attention.

ERIC Educational Resources Information Center

Connolly, Charlene; Sanders, William

This study examined the amount of perceived stress and its dimensions on 121 elementary and secondary school teachers. Correlations were found between the "Emotional Exhaustion" dimension of stress and gender (males experienced more burnout) and years of teaching (teachers with more years at their present job experienced more burnout).…

Exploring School Stress in Middle Childhood: Interpretations, Experiences, and Coping

ERIC Educational Resources Information Center

Sotardi, Valerie A.

2017-01-01

With increased academic and social challenges at school, middle childhood can be a particularly stressful time. The present study explored how a sample of children from a supportive learning environment interpreted, experienced and reported coping with everyday stress at school. Using a phenomenological approach, third graders attending an…

Stress, Coping, and Internet Use of College Students

ERIC Educational Resources Information Center

Deatherage, Scott; Servaty-Seib, Heather L.; Aksoz, Idil

2014-01-01

College students experience stressful life events and little research exists on the role the Internet may play in students' coping. Objective: The purpose of the present study was to examine associations among perceived stress, time spent on the Internet, underlying motives for utilizing the Internet, problematic Internet use, and traditional…

Stability of sublethal acid stress adaptaion and induced cross protection against lauric arginate in Listeria monocytogenes

USDA-ARS?s Scientific Manuscript database

The stability of acid stress adaptation in Listeria monocytogenes and its induced cross protection effect against GRAS (generally recognized as safe) antimicrobial compounds has never been investigated before. In the present study, the acid stress adaptation in L. monocytogenes was initially induced...

Adverse effects of stress on microbiota

USDA-ARS?s Scientific Manuscript database

The complex communities of microorganisms that colonize the gastrointestinal tract impact the health status of an animal. The health of an animal as well as production traits are also affected by exposure to stress. The aim of present study was to evaluate the effects of dehorning stress on the gut ...

Stress analysis in platform-switching implants: a 3-dimensional finite element study.

PubMed

Pellizzer, Eduardo Piza; Verri, Fellippo Ramos; Falcón-Antenucci, Rosse Mary; Júnior, Joel Ferreira Santiago; de Carvalho, Paulo Sérgio Perri; de Moraes, Sandra Lúcia Dantas; Noritomi, Pedro Yoshito

2012-10-01

The aim of this study was to evaluate the influence of the platform-switching technique on stress distribution in implant, abutment, and peri-implant tissues, through a 3-dimensional finite element study. Three 3-dimensional mandibular models were fabricated using the SolidWorks 2006 and InVesalius software. Each model was composed of a bone block with one implant 10 mm long and of different diameters (3.75 and 5.00 mm). The UCLA abutments also ranged in diameter from 5.00 mm to 4.1 mm. After obtaining the geometries, the models were transferred to the software FEMAP 10.0 for pre- and postprocessing of finite elements to generate the mesh, loading, and boundary conditions. A total load of 200 N was applied in axial (0°), oblique (45°), and lateral (90°) directions. The models were solved by the software NeiNastran 9.0 and transferred to the software FEMAP 10.0 to obtain the results that were visualized through von Mises and maximum principal stress maps. Model A (implants with 3.75 mm/abutment with 4.1 mm) exhibited the highest area of stress concentration with all loadings (axial, oblique, and lateral) for the implant and the abutment. All models presented the stress areas at the abutment level and at the implant/abutment interface. Models B (implant with 5.0 mm/abutment with 5.0 mm) and C (implant with 5.0 mm/abutment with 4.1 mm) presented minor areas of stress concentration and similar distribution pattern. For the cortical bone, low stress concentration was observed in the peri-implant region for models B and C in comparison to model A. The trabecular bone exhibited low stress that was well distributed in models B and C. Model A presented the highest stress concentration. Model B exhibited better stress distribution. There was no significant difference between the large-diameter implants (models B and C).

Academic Stress and Self-Regulation among University Students in Malaysia: Mediator Role of Mindfulness

PubMed Central

Hj Ramli, Nur Hamizah; Alavi, Masoumeh; Mehrinezhad, Seyed Abolghasem; Ahmadi, Atefeh

2018-01-01

Academic stress is the most common emotional or mental state that students experience during their studies. Stress is a result of a wide range of issues, including test and exam burden, a demanding course, a different educational system, and thinking about future plans upon graduation. A sizeable body of literature in stress management research has found that self-regulation and being mindful will help students to cope up with the stress and dodge long-term negative consequences, such as substance abuse. The present study aims to investigate the influence of academic stress, self-regulation, and mindfulness among undergraduate students in Klang Valley, Malaysia, and to identify mindfulness as the mediator between academic stress and self-regulation. For this study, a total of 384 undergraduate students in Klang Valley, Malaysia were recruited. Using Correlational analysis, results revealed that there was a significant relationship between academic stress, self-regulation, and mindfulness. However, using SPSS mediational analysis, mindfulness did not prove the mediator role in the study. PMID:29342910

Academic Stress and Self-Regulation among University Students in Malaysia: Mediator Role of Mindfulness.

PubMed

Hj Ramli, Nur Hamizah; Alavi, Masoumeh; Mehrinezhad, Seyed Abolghasem; Ahmadi, Atefeh

2018-01-15

Academic stress is the most common emotional or mental state that students experience during their studies. Stress is a result of a wide range of issues, including test and exam burden, a demanding course, a different educational system, and thinking about future plans upon graduation. A sizeable body of literature in stress management research has found that self-regulation and being mindful will help students to cope up with the stress and dodge long-term negative consequences, such as substance abuse. The present study aims to investigate the influence of academic stress, self-regulation, and mindfulness among undergraduate students in Klang Valley, Malaysia, and to identify mindfulness as the mediator between academic stress and self-regulation. For this study, a total of 384 undergraduate students in Klang Valley, Malaysia were recruited. Using Correlational analysis, results revealed that there was a significant relationship between academic stress, self-regulation, and mindfulness. However, using SPSS mediational analysis, mindfulness did not prove the mediator role in the study.

Soft-food diet induces oxidative stress in the rat brain.

PubMed

Yoshino, Fumihiko; Yoshida, Ayaka; Hori, Norio; Ono, Yumie; Kimoto, Katsuhiko; Onozuka, Minoru; Lee, Masaichi Chang-il

2012-02-02

Decreased dopamine (DA) release in the hippocampus may be caused by dysfunctional mastication, although the mechanisms involved remain unclear. The present study examined the effects of soft- and hard-food diets on oxidative stress in the brain, and the relationship between these effects and hippocampal DA levels. The present study showed that DA release in the hippocampus was decreased in rats fed a soft-food diet. Electron spin resonance studies using the nitroxyl spin probe 3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine-1-oxyl directly demonstrated a high level of oxidative stress in the rat brain due to soft-food diet feeding. In addition, we confirmed that DA directly react with reactive oxygen species such as hydroxyl radical and superoxide. These observations suggest that soft-food diet feeding enhances oxidative stress, which leads to oxidation and a decrease in the release of DA in the hippocampus of rats. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Thermal stresses investigation of a gas turbine blade

NASA Astrophysics Data System (ADS)

Gowreesh, S.; Pravin, V. K.; Rajagopal, K.; Veena, P. H.

2012-06-01

The analysis of structural and thermal stress values that are produced while the turbine is operating are the key factors of study while designing the next generation gas turbines. The present study examines structural, thermal, modal analysis of the first stage rotor blade of a two stage gas turbine. The design features of the turbine segment of the gas turbine have been taken from the preliminary design of a power turbine for maximization of an existing turbojet engine with optimized dump gap of the combustion chamber, since the allowable temperature on the turbine blade dependents on the hot gas temperatures from the combustion chamber. In the present paper simplified 3-D Finite Element models are developed with governing boundary conditions and solved using the commercial FEA software ANSYS. As the temperature has a significant effect on the overall stress on the rotor blades, a detail study on mechanical and thermal stresses are estimated and evaluated with the experimental values.

Perceived Parental Bonding, Fear of Failure and Stress during Class Presentations

ERIC Educational Resources Information Center

Sideridis, Georgios D.; Kafetsios, Konstantinos

2008-01-01

The purpose of the present studies was to test the hypothesis that students' perceptions of parental bonding may be predictive of how individuals approach achievement situations. It was hypothesized that reports of parental overprotection would be predictive of elevated fears and subsequent stress and low achievement compared to perceived parental…

SIRT1 activation inhibits hyperglycemia-induced apoptosis by reducing oxidative stress and mitochondrial dysfunction in human endothelial cells.

PubMed

Wang, Shengqiang; Wang, Jian; Zhao, Airong; Li, Jigang

2017-09-01

Sustained hyperglycemic stimulation of vascular cells is involved in the pathogenesis of diabetes mellitus‑induced cardiovascular complications. Silent information regulator T1 (SIRT1), a mammalian sirtuin, has been previously recognized to protect endothelial cells against hyperglycemia‑induced oxidative stress. In the present study, human umbilical vein endothelial cells (HUV‑EC‑C) were treated with D‑glucose, and the levels of oxidative stress, mitochondrial dysfunction, the rate of apoptosis and SIRT1 activity were measured. The effect of manipulated SIRT1 activity on hyperglycemia‑induced oxidative stress, mitochondrial dysfunction and apoptosis was then assessed using the SIRT1 activator, resveratrol (RSV), and the SIRT1 inhibitor, sirtinol. The present study confirmed that hyperglycemia promotes oxidative stress and mitochondrial dysfunction in HUV‑EC‑C cells. The accumulation of reactive oxygen species, the swelling of mitochondria, the ratio of adenosine 5'‑diphosphate to adenosine 5'‑triphosphate and localized mitochondrial superoxide levels were all increased following D‑glucose treatment, whereas the mitochondrial membrane potential was significantly reduced by >50 mg/ml D‑glucose treatment. In addition, hyperglycemia was confirmed to induce apoptosis in HUV‑EC‑C cells. Furthermore, the results confirmed the prevention and aggravation of hyperglycemia‑induced apoptosis by RSV treatment and sirtinol treatment, via the amelioration and enhancement of oxidative stress and mitochondrial dysfunction in HUV‑EC‑C cells, respectively. In conclusion, the present study revealed that hyperglycemia promotes oxidative stress, mitochondrial dysfunction and apoptosis in HUV‑EC‑C cells, and manipulation of SIRT1 activity regulated hyperglycemia‑induced mitochondrial dysfunction and apoptosis in HUV‑EC‑C cells. The data revealed the protective effect of SIRT1 against hyperglycemia‑induced apoptosis via the alleviation of mitochondrial dysfunction and oxidative stress.

Endoplasmic reticulum stress is involved in the lidocaine-induced apoptosis in SH-SY5Y neuroblastoma cells.

PubMed

Li, Kehan; Han, Xuechang

2015-05-01

Lidocaine has been indicated to promote apoptosis and to promote endoplasmic reticulum (ER) stress. However, the mechanism underlining ER stress-mediated apoptosis is unclear. In the present study, we investigated the promotion to ER stress in the lidocaine-induced apoptosis in human neuroblastoma SH-SY5Y cells. Firstly, we confirmed that lidocaine treatment induced apoptosis in SH-SY5Y cells, time-dependently and dose-dependently, via MTT cell viability assay and annexin V/FITC apoptosis detection with a FACScan flow cytometer. And the anti-apoptosis Bcl-2 and Bcl-xL were downregulated, whereas the apoptosis-executive caspase 3 was promoted through Western blot assay and caspase 3 activity assay. Moreover, the ER stress-associated binding immunoglobulin protein (BiP), PKR-like ER kinase (PERK), activating transcription factor 4 (ATF4) and CCAAT/enhancer-binding protein homologous protein (CHOP) were also upregulated at both mRNA and protein levels by lidocaine treatment. On the other hand, downregulation of the ER stress-associated BiP by RNAi method not only blocked the lidocaine-promoted ER stress but also attenuated the lidocaine-induced SH-SY5Y cell apoptosis. In conclusion, the present study confirmed the involvement of ER stress in the lidocaine-induced apoptosis in human neuroblastoma SH-SY5Y cells. Our study provides a better understanding on the mechanism of lidocaine's neurovirulence.

Personality differences in the susceptibility to stress-eating: The influence of emotional control and impulsivity.

PubMed

Van Blyderveen, Sherry; Lafrance, Adele; Emond, Michael; Kosmerly, Stacey; O'Connor, Megan; Chang, Felicia

2016-12-01

Stress has been associated with deviations from typical eating patterns, with respect to both food choice and overall caloric intake. Both increases and decreases in dietary intake have been previously noted in response to stress. The purpose of the present study was to determine whether the affect regulation strategies of emotional control and impulsivity predict susceptibility to eating in response to stress. Specifically, it was anticipated that emotional suppression would predict decreases in caloric intake, whereas impulsivity would predict increases in caloric intake, in response to a stressor. Participants were randomly assigned to view either a video designed to elicit stress or a control video. Food was provided during the video and the amount and type of food consumed was measured. Participants' nutritional intake was greater in the stress condition than in the control condition. One aspect of affect regulation, impulsivity, moderated this relationship, with a tendency for greater impulsivity to be associated with greater caloric intake in the stress condition. The degree of negative affect that participants experienced in the stress condition predicted food choice and overall caloric intake. Both emotional control and impulsivity moderated the relationship between negative affect and both food choice and caloric intake in the stress condition. The present study highlights the importance of considering the personality attributes of both impulsivity and emotional suppression in understanding stress eating. Copyright © 2016. Published by Elsevier Ltd.

[Stress in Medical Students: A Cross-Sectional Study on the Relevance of Attachment Style and Structural Integration].

PubMed

Bugaj, Till Johannes; Müksch, Christine; Ehrenthal, Johannes C; Köhl-Hackert, Nadja; Schauenburg, Henning; Huber, Julia; Schmid, Carolin; Erschens, Rebecca; Junne, Florian; Herzog, Wolfgang; Nikendei, Christoph

2016-02-01

From year one of studying medicine an increase of psychological stress is found. The relationship between the occurrence of this stress and attachment patterns or structural personality functions remains unclear. The present study aimed at investigating whether a relationship between the enduring personality variables, attachment style and level of structural integration of the personality, and acute stress experience at the beginning of medical students' studies exists. In this study, all students in the first semester of medicine were invited to participate in a study to identify stress factors via questionnaire (MBI-SS, PSQ, PHQ-9, GAD-7) in the WS 2013/2014. Simultaneously, the predominant attachment style (RQ-2) and structural abilities (OPD-SFK) were evaluated. The study included 293 students (return: 91.3%). Securely attached students experienced significantly less stress than insecurely attached students (p=0.019). Students with a high level of structural integration showed significantly less stress burden (p<0.001) and lower exhaustion- (p<0.001) and cynicism values (p<0.001), while showing a higher experience of self-efficacy (p<0.001). The influence of attachment behavior on stress experience is mediated by the level of the structural integration of the personality. Significant correlations exist between attachment style and the level of structural integration of the personality, and burnout risk as well as stress burden. The level of structural integration of the personality mediates the relationship between the attachment-related "model of self" and stress experience, i. e. a positive "model of self" can have a stress-protective effect when good structural abilities are present. Practical implication: An insecure attachment style and a low level of structural integration may be associated with higher stress experience when transitioning to study. The results suggest that the enduring personality variable attachment style, mediated by the level of structural integration of the personality, leads to higher stress and burnout experience. Affected students could be supported by early preventive measures enabling the sustainable preparation for this transitional period. Longitudinal prospective studies are needed to explore if the assumption is applicable that pre-existing vulnerabilities in school are exacerbated at this transitional stage. © Georg Thieme Verlag KG Stuttgart · New York.

Occupational stress and health-related quality of life among public sector bank employees: A cross-sectional study in Mysore, Karnataka, India

PubMed Central

Malamardi, Sowmya N.; Kamath, Ramachandra; Tiwari, Rajnarayan; Nair, Binu Valsalakumari Sreekumaran; Chandrasekaran, Varalakshmi; Phadnis, Sameer

2015-01-01

Background: Occupational morbidities have been estimated to cause an economic loss up to 10–20% of the gross national product of a country. It is an important cause of occupational morbidity and decreased quality of life (QOL) for the workers. Aim: The aim of the present study is to assess the level of occupational stress and its association with the QOL among the public sector bank employees. Materials and Methods: The present study was conducted among employees of public sector banks in Mysore district, Karnataka, India. A cross-sectional study design was used for the study. Job stress was measured by using occupational stress index (OSI) scale questionnaire and health-related QOL was measured using the short form 12 (SF-12) questionnaire. The sample size estimated for the study was 526 and cluster random sampling technique was used. Chi-square test was used to find the association between the study variables and level of stress. Multiple linear regression model was used to find the determinants of health-related QOL among the study subjects. Results: The total number of the study subjects was 546 out of which 57% were males and 43% were females. The proportion of study subjects reporting to be current smokers was 4.2% and almost all study subjects reported occasional alcohol consumption. The mean physical component summary (PCS) score and mental component summary (MCS) using the original United States standardization were 47.90 and 48.30, respectively. The individuals with mild stress scored higher in both PCS and MCS than the individuals who had moderate to severe stress levels. There was significant association of health related quality of life with the age of the respondent,presence of at least one morbidity and level of stress with health-related QOL. Conclusion: This study has shown an association of occupational stress with the QOL. There is a need for interventions aimed at mitigating the occupational stress among employees of the banking sector. PMID:26957810

An Analysis of Interfacial Stresses in Steel Beams Bonded With a Thin Composite Plate Under Thermomechanical Loading

NASA Astrophysics Data System (ADS)

Benyoucef, S.; Tounsi, A.; Yeghnem, R.; Bachir Bouiadjra, M.; Adda Bedia, E. A.

2014-01-01

The strengthening of steel structures in situ with externally bonded fiber-reinforced plastic (FRP) composite sheets is increasingly being used for the repair and rehabilitation of existing structures. The previous researchers have developed several analytical methods to predict the interface performance of bonded repairs. An important feature of a reinforced steel beam is the significant stress concentration in the adhesive at the ends of the FRP plate. In this paper, a closed-form solution for the interfacial shear and normal stresses in simply supported steel beams strengthened with a bonded FRP plate and subjected to thermomechanical loadings is presented. The shear strains of the adherends are included in the present theoretical analysis by assuming a parabolic distribution of shear stress across their thickness. Contrary to some existing studies, the assumption that both adherends have the same curvature is not used in the present study. The results of this numerical study are beneficial for understanding the mechanical behavior of material interfaces and for the design of hybrid FRP-reinforced steel structures.

Stress field forming of sector array transducers for vibro-acoustography.

PubMed

Silva, Glauber T; Chen, Shigao; Frery, Alejandro C; Greenleaf, James F; Fatemi, Mostafa

2005-11-01

This paper presents a study of the stress field forming of sector array transducers for vibro-acoustography applications. The system point-spread function (PSF) is given in terms of the dynamic radiation stress exerted on a point target by a dual ultrasound beam with slightly different frequencies. The radiation stress is calculated by assuming that the resulting ultrasound beam is a plane wave. The stress is proportional to the product of the velocity potential of each incident ultrasound beam. The beamforming and stress field forming of sector array transducers are analyzed through linear acoustics. An expression for the velocity potential produced by sector array transducers is derived. The vibro-acoustography PSF is evaluated numerically. A comparison between the PSF of a sector array and a confocal transducers is presented. The compared characteristics of the PSF are sidelobe levels, transverse, and in-depth spatial resolution. Indeed, one motivation to study sector transducers is the fact the depth-of-field of these transducers should be smaller than that of same size confocal transducers. An experimental setup was used to validate the theoretical PSF of sector array transducers. Results show that the measured PSF is in good agreement with the theoretical predications. Vibro-acoustography images of a breast-phantom by both transducers are presented and discussed.

Impact of composite plates: Analysis of stresses and forces

NASA Technical Reports Server (NTRS)

Moon, F. C.; Kim, B. S.; Fang-Landau, S. R.

1976-01-01

The foreign object damage resistance of composite fan blades was studied. Edge impact stresses in an anisotropic plate were first calculated incorporating a constrained layer damping model. It is shown that a very thin damping layer can dramatically decrease the maximum normal impact stresses. A multilayer model of a composite plate is then presented which allows computation of the interlaminar normal and shear stresses. Results are presented for the stresses due to a line impact load normal to the plane of a composite plate. It is shown that significant interlaminar tensile stresses can develop during impact. A computer code was developed for this problem using the fast Fourier transform. A marker and cell computer code were also used to investigate the hydrodynamic impact of a fluid slug against a wall or turbine blade. Application of fluid modeling of bird impact is reviewed.

Elasticity solutions for a class of composite laminate problems with stress singularities

NASA Technical Reports Server (NTRS)

Wang, S. S.

1983-01-01

A study on the fundamental mechanics of fiber-reinforced composite laminates with stress singularities is presented. Based on the theory of anisotropic elasticity and Lekhnitskii's complex-variable stress potentials, a system of coupled governing partial differential equations are established. An eigenfunction expansion method is introduced to determine the orders of stress singularities in composite laminates with various geometric configurations and material systems. Complete elasticity solutions are obtained for this class of singular composite laminate mechanics problems. Homogeneous solutions in eigenfunction series and particular solutions in polynomials are presented for several cases of interest. Three examples are given to illustrate the method of approach and the basic nature of the singular laminate elasticity solutions. The first problem is the well-known laminate free-edge stress problem, which has a rather weak stress singularity. The second problem is the important composite delamination problem, which has a strong crack-tip stress singularity. The third problem is the commonly encountered bonded composite joints, which has a complex solution structure with moderate orders of stress singularities.

Stress prompts habit behavior in humans.

PubMed

Schwabe, Lars; Wolf, Oliver T

2009-06-03

Instrumental behavior can be controlled by goal-directed action-outcome and habitual stimulus-response processes that are supported by anatomically distinct brain systems. Based on previous findings showing that stress modulates the interaction of "cognitive" and "habit" memory systems, we asked in the presented study whether stress may coordinate goal-directed and habit processes in instrumental learning. For this purpose, participants were exposed to stress (socially evaluated cold pressor test) or a control condition before they were trained to perform two instrumental actions that were associated with two distinct food outcomes. After training, one of these food outcomes was selectively devalued as subjects were saturated with that food. Next, subjects were presented the two instrumental actions in extinction. Stress before training in the instrumental task rendered participants' behavior insensitive to the change in the value of the food outcomes, that is stress led to habit performance. Moreover, stress reduced subjects' explicit knowledge of the action-outcome contingencies. These results demonstrate for the first time that stress promotes habits at the expense of goal-directed performance in humans.

Stronger cortisol response to acute psychosocial stress is correlated with larger decrease in temporal sensitivity

PubMed Central

Yao, Zhuxi; Jiang, Caihong; Zhang, Kan; Wu, Jianhui

2016-01-01

As a fundamental dimension of cognition and behavior, time perception has been found to be sensitive to stress. However, how one’s time perception changes with responses to stress is still unclear. The present study aimed to investigate the relationship between stress-induced cortisol response and time perception. A group of 40 healthy young male adults performed a temporal bisection task before and after the Trier Social Stress Test for a stress condition. A control group of 27 male participants completed the same time perception task without stress induction. In the temporal bisection task, participants were first presented with short (400 ms) and long (1,600 ms) visual signals serving as anchor durations and then required to judge whether the intermediate probe durations were more similar to the short or the long anchor. The bisection point and Weber ratio were calculated and indicated the subjective duration and the temporal sensitivity, respectively. Data showed that participants in the stress group had significantly increased salivary cortisol levels, heart rates, and negative affects compared with those in the control group. The results did not show significant group differences for the subjective duration or the temporal sensitivity. However, the results showed a significant positive correlation between stress-induced cortisol responses and decreases in temporal sensitivity indexed by increases in the Weber ratio. This correlation was not observed for the control group. Changes in subjective duration indexed by temporal bisection points were not correlated with cortisol reactivity in both the groups. In conclusion, the present study found that although no significant change was observed in time perception after an acute stressor on the group-level comparison (i.e., stress vs. nonstress group), individuals with stronger cortisol responses to stress showed a larger decrease in temporal sensitivity. This finding may provide insight into the understanding of the relationship between stress and temporal sensitivity. PMID:27257544

Predicting sleep quality from stress and prior sleep--a study of day-to-day covariation across six weeks.

PubMed

Åkerstedt, Torbjörn; Orsini, Nicola; Petersen, Helena; Axelsson, John; Lekander, Mats; Kecklund, Göran

2012-06-01

The connection between stress and sleep is well established in cross-sectional questionnaire studies and in a few prospective studies. Here, the intention was to study the link between stress and sleep on a day-to-day basis across 42 days. Fifty participants kept a sleep/wake diary across 42 days and responded to daily questions on sleep and stress. The results were analyzed with a mixed model approach using stress during the prior day to predict morning ratings of sleep quality. The results showed that bedtime stress and worries were the main predictors of sleep quality, but that, also, late awakening, short prior sleep, high quality of prior sleep, and good health the prior day predicted higher sleep quality. Stress during the day predicts subsequent sleep quality on a day-to-day basis across 42 days. The observed range of variation in stress/worries was modest, which is why it is suggested that the present data underestimates the impact of stress on subsequent sleep quality. Copyright © 2012 Elsevier B.V. All rights reserved.

The role of predictability and structure in word stress processing: an ERP study on Cairene Arabic and a cross-linguistic comparison

PubMed Central

Domahs, Ulrike; Knaus, Johannes A.; El Shanawany, Heba; Wiese, Richard

2014-01-01

This article presents neurolinguistic data on word stress perception in Cairene Arabic, in comparison to previous results on German and Turkish. The main goal is to investigate how central properties of stress systems such as predictability of stress and metrical structure are reflected in the prosodic processing of words. Cairene Arabic is a language with a regular foot-based word stress system, leading to highly predictable placement of word stress. An ERP study on Cairene Arabic is reported, in which a stress violation paradigm is used to investigate the factors predictability of stress and foot structure. The results of the experiment show that for Cairene Arabic the internal structure of prosodic words in terms of feet determines prosodic processing. This structure effect is complemented by a frequency effect for stress patterns. PMID:25374546

Stress and coping styles are associated with severe fatigue in medical students.

PubMed

Tanaka, Masaaki; Fukuda, Sanae; Mizuno, Kei; Kuratsune, Hirohiko; Watanabe, Yasuyoshi

2009-01-01

Fatigue is a common complaint among medical students and researchers consider it to be related to poor academic outcomes. The authors' goal in the present study was to determine whether stress and coping strategies were associated with fatigue in medical students. The study group consisted of 73 second-year healthy students attending the Osaka City University Graduate School of Medicine. Participants completed a questionnaire about fatigue (Japanese version of Chalder Fatigue Scale), stress, stress coping (Japanese version of the Coping Inventory for Stressful Situations), overwork, and nocturnal sleeping hours. On univariate and multivariate logistic regression analyses adjusted for age and gender, stress was positively associated with fatigue. In addition, after adjustment for age, gender, and emotion- and task-oriented stress coping activities, avoidance-oriented stress coping activity was associated with fatigue. The results suggest that stress and the coping style are correlated with fatigue in medical students.

Chronic stress, catecholamines, and sleep disturbance at Three Mile Island.

PubMed

Davidson, L M; Fleming, R; Baum, A

1987-01-01

The present study was concerned with the relationship between chronic stress and sleep disturbance. Previous research has provided evidence of chronic stress responding among people living near the Three Mile Island nuclear generating facility. Compared to control subjects, the TMI group has exhibited greater symptom reporting, poorer performance on behavioral measures of concentration, and elevated levels of urinary norepinephrine and epinephrine. Other research has suggested a relationship between arousal and insomnia. The extent to which stress and sleep disturbances were experienced by residents at TMI was examined and compared to levels of stress and sleep disturbance among a group of control subjects. The relationship between stress and sleep disturbances was also examined. Results indicated that TMI area residents exhibited more stress than the controls and reported greater disturbance of sleep. Modest relationships among stress and sleep measures suggested that the symptoms of stress measured in this study were not primary determinants of sleep problems.

Stress in migraine: personality-dependent vulnerability, life events, and gender are of significance

PubMed Central

2011-01-01

Background and aim The individual's experiences of stress as well as constitutional factors, including high neuroticism and female gender, are known determinants for migraine. The present aim was to further elucidate factors of personality and stress, including life events, in relation to gender in migraine. Methods A cross-sectional study was performed on 150 persons, 106 women and 44 men, suffering from at least two migraine attacks a month. All obtained a doctor-defined migraine diagnosis based on a structured face-to-face interview concerning their health situation and current and prior stress. All of them also answered validated questionnaires regarding personality traits (SSP), life events, and perceived ongoing stress. Results The personality trait inventory showed high mean scores for stress susceptibility and low mean scores for aggressiveness and adventure seeking, both for women and for men, as well as high mean scores for psychic and somatic anxiety in women. Stress susceptibility, the overall most deviant trait, correlated strikingly with current level of stress in both sexes. In women, stress susceptibility also correlated strongly with experiences of negative life events. Tension-type headache, anxiety, and depression were approximately twice as prevalent in women compared to men. Conclusions The present study confirms previous research, showing that stress is an important factor in migraine. Stress susceptibility, life events, and concomitant psychosomatic illnesses should be considered important when evaluating individuals with migraine, and gender aspects need to be taken into account. PMID:21668386

Perceived stress, life events & coping among higher secondary students of Hyderabad, India: A pilot study

PubMed Central

Augustine, Little Flower; Vazir, Shahnaz; Rao, Sylvia Fernandez; Vishnu Vardhana Rao, M.; Laxmaiah, A; Nair, K. Madhavan

2011-01-01

Background & objectives: Psychosocial stressors leading to allostatic load need to be explored further as these have great scope for early intervention. Stress studies done in India are mostly based on sources of stress and objective measures of stress. Therefore, the objective of the present study was to assess stress appraisal among students (16-17 yr) and to identify institution-specific differences (Private vs. Government) in stress appraisal and coping. Methods: The study was carried out among 16-17 yr old apparently normal students. Eighty students were recruited from six schools ensuring equal representation from gender/category of schools (Government/ Private). Validated and culturally adaptable behavioural scales for perceived stress (PSS), stressful life events (LES) and coping were administered. Psychological morbidity was assessed using GHQ-12. Data on 75 students were available for statistical analysis. Results: The students of both Government and Private schools showed similar stress perception, though the former tend to have a higher mean score. The scores were significantly higher on avoidance coping (P<0.05). The stepwise regression model showed coping as the independent predictor of perceived stress (R2= 10%). Interpretation & conclusions: Students from Government schools had significantly higher scores on avoidance coping and therefore, suitable for a systematic study on chronic stress for early intervention. PMID:21808136

Can Molecular Hippocampal Alterations Explain Behavioral Differences in Prenatally Stressed Rats?

EPA Science Inventory

Studies in both humans and animals have shown that prenatal stress can alter cognitive function and other neurological behaviors in adult offspring. One possible underlying mechanism for this may lie with alterations in hippocampal gene expression. The present study examined geno...

Characteristics of global strong earthquakes and their implications for the present-day stress pattern

NASA Astrophysics Data System (ADS)

Wei, Ju; Weifeng, Sun; Jinhui, Luo

2017-10-01

Earthquakes occurred on the surface of the Earth contain comprehensive and abundant geodynamic connotations, and can serve as important sources for describing the present-day stress field and regime. An important advantage of the earthquake focal mechanism solution is the ability to obtain the stress pattern information at depth in the lithosphere. During the past several decades, an increasing number of focal mechanisms were available for estimating the present-day stress field and regime. In the present study, altogether 553 focal mechanism data ranging from the year 1976 to 2017 with Mw ≥ 7.0 were compiled in the Global/Harvard centroid moment tensor (CMT) catalogue, the characteristics of global strong earthquakes and the present-day stress pattern were analyzed based on these data. The majority of global strong earthquakes are located around the plate boundaries, shallow-focus, and thrust faulting (TF) regime. We grouped 518 of them into 12 regions (Boxes) based on their geographical proximity and tectonic setting. For each box, the present-day stress field and regime were obtained by formal stress inversion. The results indicated that the maximum horizontal principal stress direction was ˜ N-S-trending in western North America continent and southwestern Indonesia, ˜ NNE-SSW-trending in western Middle America and central Asia, ˜ NE-SW in southeastern South America continent and northeastern Australia, ˜ NEE-SWW-trending in western South America continent and southeastern Asia, ˜ E-W-trending in southeastern Australia, and ˜ NW-SE-trending in eastern Asia. The results can provide additional constraints to the driving forces and geodynamic models, allowing them to explain the current plate interactions and crustal tectonic complexities better.

Relationship between general intelligence, emotional intelligence, stress levels and stress reactivity.

PubMed

Singh, Yogesh; Sharma, Ratna

2012-07-01

Stressful life events and daily life stresses have both deleterious and cumulative effects on human body. In several studies, stress has been shown to affect various parameter of higher mental function like attention, concentration, learning and memory. Present study was designed to explore the relationship among GI level, EI level, psychological stress levels and acute stress reactivity in young normal healthy subjects. The study was conducted on thirty four healthy male student volunteers to study a) acute stress reactivity in subjects with varying levels of General Intelligence (GI) and Emotional Intelligence (EI) and b) correlation between GI, EI, acute stress and perceived stress. Baseline GI and EI and acute stress and perceived stress scores were measured by standard assessment scales. Using median value of GI and EI scores as cutoff values, subjects were categorized into four groups. Among different GI-EI groups, acute stress reactivity was similar but salivary Cortisol (especially post stressor level) and perceived stress level was a differentiating factor. High level of EI was associated inversely with acute and chronic perceived stress level. Significant correlation was found between acute and chronic perceived stress levels. Level of general intelligence showed no relation to acute or chronic stress levels as well as acute stress reactivity. The differences in various groups of GI and EI had no effect on the baseline and post stress performance on Sternberg memory test and all the three conditions of Stroop test. In conclusion emotional intelligence as an attribute is better suited to handle day to day acute stress and chronic perceived stress.

Response inhibition and cognitive appraisal in clients with acute stress disorder and posttraumatic stress disorder.

PubMed

Abolghasemi, Abass; Bakhshian, Fereshteh; Narimani, Mohammad

2013-08-01

The purpose of the present study was to compare response inhibition and cognitive appraisal in clients with acute stress disorder, clients with posttraumatic stress disorder, and normal individuals. This was a comparative study. The sample consisted of 40 clients with acute stress disorder, 40 patients with posttraumatic stress disorder, and 40 normal individuals from Mazandaran province selected through convenience sampling method. Data were collected using Composite International Diagnostic Interview, Stroop Color-Word Test, Posttraumatic Cognitions Inventory, and the Impact of Event Scale. Results showed that individuals with acute stress disorder are less able to inhibit inappropriate responses and have more impaired cognitive appraisals compared to those with posttraumatic stress disorder. Moreover, results showed that response inhibition and cognitive appraisal explain 75% of the variance in posttraumatic stress disorder symptoms and 38% of the variance in posttraumatic stress disorder symptoms. The findings suggest that response inhibition and cognitive appraisal are two variables that influence the severity of posttraumatic stress disorder and acute stress disorder symptoms. Also, these results have important implications for pathology, prevention, and treatment of posttraumatic stress disorder and acute stress disorder.

Foreign-born physicians' perceptions of discrimination and stress in Finland: a cross-sectional questionnaire study.

PubMed

Heponiemi, Tarja; Hietapakka, Laura; Lehtoaro, Salla; Aalto, Anna-Mari

2018-06-07

Foreign-born physicians fill in the shortage of physicians in many developed countries. Labour market theory and previous studies suggest that foreign-born physicians may be a disadvantaged group with a higher likelihood of discrimination and less prestigious jobs. The present study examines foreign-born physicians' experiences of discrimination (coming from management, colleagues and patients separately) and patient-related stress and integration-related stress, and it examines how gender, age, employment sector, country of birth, years from getting a practicing license in Finland, language problems, cross-cultural training, cross-cultural empathy, team climate and skill discretion were associated with these factors. The present study was a cross-sectional questionnaire study among 371 foreign-born physicians in Finland, aged between 26 and 65 (65% women). Analyses of covariance and logistic regression analyses were conducted to examine the associations. A good team climate and high cross-cultural empathy were associated with lower likelihoods of discrimination from all sources, patient-related stress and integration-related stress. Skill discretion was associated with lower levels of integration-related stress and discrimination from management and colleagues. Language problems were associated with higher levels of integration-related stress. The biggest sources of discrimination were patients and their relatives. The present study showed the importance of a good team climate, cross-cultural empathy and patience, skill discretion and language skills in regard to the proper integration of foreign-born health care employees into the workplace. Good job resources, such as a good team climate and the possibility to use one's skills, may help foreign-born employees, for instance by giving them support when needed and offering flexibility. Health care organizations should invest in continuous language training for foreign-born employees and also offer support when there are language problems. Moreover, it seems that training increasing cross-cultural empathy and patience might be beneficial.

The Community Child Health Network Life Stress Interview: a brief chronic stress measure for community health research.

PubMed

Tanner Stapleton, Lynlee R; Dunkel Schetter, Christine; Dooley, Larissa N; Guardino, Christine M; Huynh, Jan; Paek, Cynthia; Clark-Kauffman, Elizabeth; Schafer, Peter; Woolard, Richard; Lanzi, Robin Gaines

2016-07-01

Chronic stress is implicated in many theories as a contributor to a wide range of physical and mental health problems. The current study describes the development of a chronic stress measure that was based on the UCLA Life Stress Interview (LSI) and adapted in collaboration with community partners for use in a large community health study of low-income, ethnically diverse parents of infants in the USA (Community Child Health Network [CCHN]). We describe the instrument, its purpose and adaptations, implementation, and results of a reliability study in a subsample of the larger study cohort. Interviews with 272 mothers were included in the present study. Chronic stress was assessed using the CCHN LSI, an instrument designed for administration by trained community interviewers to assess four domains of chronic stress, each rated by interviewers. Significant correlations ranging from small to moderate in size between chronic stress scores on this measure, other measures of stress, biomarkers of allostatic load, and mental health provide initial evidence of construct and concurrent validity. Reliability data for interviewer ratings are also provided. This relatively brief interview (15 minutes) is available for use and may be a valuable tool for researchers seeking to measure chronic stress reliably and validly in future studies with time constraints.

Emerging Thought and Research on Student, Teacher, and Administrator Stress and Coping. Research on Stress and Coping in Education

ERIC Educational Resources Information Center

Gates, Gordon S., Ed.; Wolverton, Mimi, Ed.; Gmelch, Walter H., Ed.

2007-01-01

This collection of chapters presents research focused on emerging strategies, paradigms, and theories on the sources, experiences, and consequences of stress, coping, and prevention pertaining to students, teachers and administrators. Studies analyze data collected through action research, program evaluation, surveys, qualitative interviewing,…

Investigating Adolescent Stress and Body Image

ERIC Educational Resources Information Center

Murray, Kristen M.; Byrne, Don G.; Rieger, Elizabeth

2011-01-01

Adolescent stress is clearly implicated in the development of mental health problems. However, its role in dysfunctional body image, which rises markedly in adolescence, has not been investigated. The present study examined the link between stress and body image, as well as self-esteem and depressive symptoms, in 533 high school students in grades…

Sources of Stress: Perceptions of South African TESOL Teachers

ERIC Educational Resources Information Center

Bowen, Amanda

2016-01-01

This paper presents the findings of a qualitative study investigating which factors inside and outside the classroom result in feelings of stress for TESOL teachers working at private language schools in South Africa. Using in-depth semi-structured interviews, the findings reveal three main areas that cause stress for TESOL teachers: the job of…

The Psychophysiological Impact of Burnout in Special and General Education Teachers

ERIC Educational Resources Information Center

Sacco, Matthew D. F.

2011-01-01

Teaching is considered to be a stressful occupation. Many teachers experience ongoing stress from a variety of sources, which eventually leads to burnout, and ultimately is reflected in what has become an alarming rate of attrition. The present study examined the relationship between teachers' experiences of stress, burnout, and salivary cortisol…

The Impact of Acculturative Stress and Daily Hassles on Pre-Adolescent Psychological Adjustment: Examining Anxiety Symptoms

ERIC Educational Resources Information Center

Suarez-Morales, Lourdes; Lopez, Barbara

2009-01-01

Acculturative stress in relation to anxiety symptoms has not been examined empirically in young Hispanic populations. The present study, conducted with 138 pre-adolescent Hispanic youngsters, investigated this relationship. The findings suggested that acculturative stress was related to physiological, concentration, and worrisome symptoms of…

Teacher Stress in Working with Challenging Students in Hong Kong

ERIC Educational Resources Information Center

Pang, I-Wah

2012-01-01

This article first illustrates how recent social, economic and educational development in Hong Kong contributes to teacher stress. It then presents data from an international study on teacher stress with respect to working with challenging students, i.e. students with behavioural problems. Teachers were asked to report on the perceived behavioural…

Adolescents' Perceptions of Smoking and Stress Reduction

ERIC Educational Resources Information Center

Scales, Monica B.; Monahan, Jennifer L.; Rhodes, Nancy; Roskos-Ewoldsen, David; Johnson-Turbes, Ashani

2009-01-01

The present study examined how adolescents perceive the relationship between smoking and stress and where they learn that smoking cigarettes may be an effective stress-reduction mechanism. Eight focus groups were conducted with low-income African American and European American 14- to 16-year-olds in urban and rural locations, in which they…

Parenting Beliefs, Parental Stress, and Social Support Relationships

ERIC Educational Resources Information Center

Respler-Herman, Melissa; Mowder, Barbara A.; Yasik, Anastasia E.; Shamah, Renee

2012-01-01

The present study built on prior research by examining the relationship of parental stress and social support to parenting beliefs and behaviors. A sample of 87 parents provided their views concerning the importance of parenting characteristics as well as their level of parental stress and perceived social support. These parents completed the…

Relationships among Parenting Practices, Parental Stress, Child Behaviour, and Children's Social-Cognitive Development

ERIC Educational Resources Information Center

Guajardo, Nicole R.; Snyder, Gregory; Petersen, Rachel

2009-01-01

The present study included observational and self-report measures to examine associations among parental stress, parental behaviour, child behaviour, and children's theory of mind and emotion understanding. Eighty-three parents and their 3- to 5-year-old children participated. Parents completed measures of parental stress, parenting (laxness,…

[The Effect of Social-Psychological Factors on the Development of Occupational Stress].

PubMed

Kalinina, S A; Yushkova, O I

2015-01-01

The article presents data on social-psychological factors which cause the occupational stress. The results showed that there is a link between the level of work motivation and the physiological cost of work. We observed a number of peculiarities of occupational stress development caused by psychoemotional tension depending on the class of intensity of intellectual labor; we also studied biological age of the subjects. The speed of ageing of the employees who work under conditions of emotional stress (direct or indirect responsibility for the safety of other people) was found to increase. The study suggested promising directions of occupational stress prevention.

Earthquake stress triggers, stress shadows, and seismic hazard

USGS Publications Warehouse

Harris, R.A.

2000-01-01

Many aspects of earthquake mechanics remain an enigma at the beginning of the twenty-first century. One potential bright spot is the realization that simple calculations of stress changes may explain some earthquake interactions, just as previous and ongoing studies of stress changes have begun to explain human- induced seismicity. This paper, which is an update of Harris1, reviews many published works and presents a compilation of quantitative earthquake-interaction studies from a stress change perspective. This synthesis supplies some clues about certain aspects of earthquake mechanics. It also demonstrates that much work remains to be done before we have a complete story of how earthquakes work.

Therapy of stress (takotsubo) cardiomyopathy: present shortcomings and future perspectives.

PubMed

Brunetti, Natale Daniele; Santoro, Francesco; De Gennaro, Luisa; Correale, Michele; Kentaro, Hayashi; Gaglione, Antonio; Di Biase, Matteo

2016-09-01

Several therapeutic options are available for the treatment of the acute phase of stress cardiomyopathy, pharmacological (β-blockers, diuretics, anticoagulants, antiarrhythmics, noncatecholamine inotropics [levosimendan]), and nonpharmacological (intra-aortic balloon pumping, extracorporeal membrane oxygenation), according to the wide possible clinical presentation and course of the disease. However, there is a gap in evidence, and very few data come from randomized and adequately powered studies. Some evidence supports the use of β-blockers, in particular with a short half-life, in the case of left ventricular outflow tract obstruction, and angiotensin-converting enzyme inhibitors in secondary prevention. Future perspectives include the study of genetic basis of stress cardiomyopathy, role of miRNA and neurovegetative modulation. Randomized studies, however, are surely warranted.

Stress studies in EFG

NASA Technical Reports Server (NTRS)

1983-01-01

A computer code which can account for plastic deformation effects on stress generated in silicon sheet grown at high speeds is fully operative. Stress and strain rate distributions are presented for two different sheet temperature profiles. The calculations show that residual stress levels are very sensitive to details of the cooling profile in a sheet with creep. Experimental work has been started in several areas to improve understanding of ribbon temperature profiles and stress distributions associated with a 10 cm wide ribbon cartridge system.

Posttraumatic Stress Symptom Severity and Cognitive-Based Smoking Processes Among Trauma-Exposed Treatment-Seeking Smokers: The Role of Perceived Stress

PubMed Central

Garey, Lorra; Bakhshaie, Jafar; Vujanovic, Anka A.; Reitzel, Lorraine R.; Schmidt, Norman B.; Zvolensky, Michael J.

2016-01-01

Trauma exposure and smoking co-occur at an alarmingly high rate. However, there is little understanding of the mechanisms underlying this clinically significant relation. The present study examined perceived stress as an explanatory mechanism linking posttraumatic stress symptom severity and smoking-specific avoidance/inflexibility, perceived barriers to smoking cessation, and negative affect reduction/negative reinforcement expectancies from smoking among trauma-exposed smokers. Participants were trauma-exposed, treatment-seeking daily cigarette smokers (n = 179; 48.0% female; Mage = 41.17; SD = 12.55). Results indicated that posttraumatic stress symptom severity had an indirect significant effect on each of the dependent variables via perceived stress. The present results provide empirical support that perceived stress may be an underlying mechanism that indirectly explains posttraumatic symptoms relation to smoking-specific avoidance/inflexibility, perceived barriers to smoking cessation, and negative affect reduction/negative reinforcement expectancies among trauma-exposed smokers. These findings suggest that there may be clinical utility in targeting perceived stress among trauma-exposed smokers via stress management psychoeducation and skills training. PMID:27100473

Acute stress in residents during emergency care: a study of personal and situational factors.

PubMed

Dias, Roger Daglius; Scalabrini Neto, Augusto

2017-05-01

Providing care for simulated emergency patients may induce considerable acute stress in physicians. However, the acute stress provoked in a real-life emergency room (ER) is not well known. Our aim was to assess acute stress responses in residents during real emergency care and investigate the related personal and situational factors. A cross-sectional observational study was carried out at an emergency department of a tertiary teaching hospital. All second-year internal medicine residents were invited to voluntarily participate in this study. Acute stress markers were assessed at baseline (T1), before residents started their ER shift, and immediately after an emergency situation (T2), using heart rate, systolic, and diastolic blood pressure, salivary α-amylase activity, salivary interleukin-1 β, and the State-Trait Anxiety Inventory (STAI-s and STAI-t). Twenty-four residents were assessed during 40 emergency situations. All stress markers presented a statistically significant increase between T1 and T2. IL-1 β presented the highest percent increase (141.0%, p < .001), followed by AA (99.0%, p = .002), HR (81.0%, p < .001), DBP (8.0%, p < .001), and SBP (3.0%, p < .001). In the multivariable analysis, time of residency had a negative correlation with HR during the emergency (adjusted R-square = .168; F = 8.69; p = .006), SBP response (adjusted R-square = .210; F = 6.19; p = .005) and DBP response (adjusted R-square = .293; F = 9.09; p = .001). Trait anxiety (STAI-t) was positively correlated with STAI-s (adjusted R-square = .326; F = 19.9; p < .001), and number of procedures performed during emergency care had a positive association with HR response (adjusted R-square = .241; F = 5.02; p = .005). In the present study, emergency care provoked substantial acute stress in residents. Resident experience, trait anxiety, and number of emergency procedures were independently associated with acute stress response.

Day and night heat stress trigger different transcriptomic responses in green and ripening grapevine (vitis vinifera) fruit.

PubMed

Rienth, Markus; Torregrosa, Laurent; Luchaire, Nathalie; Chatbanyong, Ratthaphon; Lecourieux, David; Kelly, Mary T; Romieu, Charles

2014-04-28

Global climate change will noticeably affect plant vegetative and reproductive development. The recent increase in temperatures has already impacted yields and composition of berries in many grapevine-growing regions. Physiological processes underlying temperature response and tolerance of the grapevine fruit have not been extensively investigated. To date, all studies investigating the molecular regulation of fleshly fruit response to abiotic stress were only conducted during the day, overlooking possible critical night-specific variations. The present study explores the night and day transcriptomic response of grapevine fruit to heat stress at several developmental stages. Short heat stresses (2 h) were applied at day and night to vines bearing clusters sequentially ordered according to the developmental stages along their vertical axes. The recently proposed microvine model (DRCF-Dwarf Rapid Cycling and Continuous Flowering) was grown in climatic chambers in order to circumvent common constraints and biases inevitable in field experiments with perennial macrovines. Post-véraison berry heterogeneity within clusters was avoided by constituting homogenous batches following organic acids and sugars measurements of individual berries. A whole genome transcriptomic approach was subsequently conducted using NimbleGen 090818 Vitis 12X (30 K) microarrays. Present work reveals significant differences in heat stress responsive pathways according to day or night treatment, in particular regarding genes associated with acidity and phenylpropanoid metabolism. Precise distinction of ripening stages led to stage-specific detection of malic acid and anthocyanin-related transcripts modulated by heat stress. Important changes in cell wall modification related processes as well as indications for heat-induced delay of ripening and sugar accumulation were observed at véraison, an effect that was reversed at later stages. This first day - night study on heat stress adaption of the grapevine berry shows that the transcriptome of fleshy fruits is differentially affected by abiotic stress at night. The present results emphasize the necessity of including different developmental stages and especially several daytime points in transcriptomic studies.

Oxidative Stress in BPH.

PubMed

Savas, M; Verit, A; Ciftci, H; Yeni, E; Aktan, E; Topal, U; Erel, O

2009-01-01

In the present study, we investigated the relationship between potency of oxidative stress and BPH and this may assist to contribute to the realistic explanation of the ethiopathogenesis of BPH. Seventy four newly diagnosed men with BPH (mean age: 54+/-11.2), who had not undergone any previous treatment for BPH, and 62 healthy volunteers (mean age: 55+/-14) were enrolled in the present study. To determine the antioxidative status of plasma, total antioxidant capacity (TAC) was calculated, and to determine the oxidative status of plasma (TOS) total peroxide levels were measured. The ratio of TAC to total peroxide was accepted as an indicator of oxidative stress (OSI). Data are presented as mean SD +/- unless specified. Student t-test and correlation analyses were used to evaluate the statistical significance differences in the median values recorded for all parameters between BPH and control group. Plasma TAC TOS were found in patients and controls (1.70 +/- 0.32, 1.68 +/- 0.19 micromol Trolox Equiv./L), (12.48 +/- 1.98, 12.40 +/- 1.14 micromol / L) respectively. OSI was calculated as 7.57 +/- 1.91, 7.48 +/- 1.33, respectively. Plasma TAC, TOS and OSI levels were not found to be significantly difference between patients and control subjects (p>0.05, p>0.05, p>0.05). The present study has shown that there were not relationship between potency of oxidative stress and BPH. Further well designed studies should be planned to find out whether the oxidative stress-related parameters play role in BPH as an interesting pathology in regard of the etiopathogenesis.

Activation of ATP-sensitive potassium channel by iptakalim normalizes stress-induced HPA axis disorder and depressive behaviour by alleviating inflammation and oxidative stress in mouse hypothalamus.

PubMed

Zhao, Xiao-Jie; Zhao, Zhan; Yang, Dan-Dan; Cao, Lu-Lu; Zhang, Ling; Ji, Juan; Gu, Jun; Huang, Ji-Ye; Sun, Xiu-Lan

2017-04-01

Stress-induced disturbance of the hypothalamic-pituitary-adrenal (HPA) axis is strongly implicated in incidence of mood disorders. A heightened neuroinflammatory response and oxidative stress play a fundamental role in the dysfunction of the HPA axis. We have previously demonstrated that iptakalim (Ipt), a new ATP-sensitive potassium (K-ATP) channel opener, could prevent oxidative injury and neuroinflammation against multiple stimuli-induced brain injury. The present study was to demonstrate the impacts of Ipt in stress-induced HPA axis disorder and depressive behavior. We employed 2 stress paradigms: 8 weeks of continuous restraint stress (chronic restraint stress, CRS) and 2h of restraint stress (acute restraint stress, ARS), to mimic both chronic stress and severe acute stress. Prolonged (4 weeks) and short-term (a single injection) Ipt treatment was administered 30min before each stress paradigm. We found that HPA axis was altered after stress, with different responses to CRS (lower ACTH and CORT, higher AVP, but normal CRH) and ARS (higher CRH, ACTH and CORT, but normal AVP). Both prolonged and short-term Ipt treatment normalized stress-induced HPA axis disorders and abnormal behaviors in mice. CRS and ARS up-regulated mRNA levels of inflammation-related molecules (TNFα, IL-1β, IL-6 and TLR4) and oxidative stress molecules (gp91phox, iNOS and Nrf2) in the mouse hypothalamus. Double immunofluorescence showed CRS and ARS increased microglia activation (CD11b and TNFα) and oxidative stress in neurons (NeuN and gp91phox), which were alleviated by Ipt. Therefore, the present study reveals that Ipt could prevent against stress-induced HPA axis disorders and depressive behavior by alleviating inflammation and oxidative stress in the hypothalamus. Copyright © 2017 Elsevier Inc. All rights reserved.

Chronic Stress Induces a Hyporeactivity of the Autonomic Nervous System in Response to Acute Mental Stressor and Impairs Cognitive Performance in Business Executives

PubMed Central

Teixeira, Renata Roland; Díaz, Miguel Mauricio; Santos, Tatiane Vanessa da Silva; Bernardes, Jean Tofoles Martins; Peixoto, Leonardo Gomes; Bocanegra, Olga Lucia; Neto, Morun Bernardino; Espindola, Foued Salmen

2015-01-01

The present study examined the incidence of chronic stress in business executives (109 subjects: 75 male and 34 female) and its relationship with cortisol levels, cognitive performance, and autonomic nervous system (ANS) reactivity after an acute mental stressor. Blood samples were collected from the subjects to measure cortisol concentration. After the sample collection, the subjects completed the Lipp Inventory of Stress Symptoms for Adults and the Stroop Color-Word Test to evaluate stress and cognitive performance levels, respectively. Saliva samples were collected prior to, immediately after, and five minutes after the test. The results revealed that 90.1% of the stressed subjects experienced stress phases that are considered chronic stress. At rest, the subjects with chronic stress showed higher cortisol levels, and no gender differences were observed. No differences were found between the stressed and non-stressed subjects regarding salivary amylase activity prior to test. Chronic stress also impaired performance on the Stroop test, which revealed higher rates of error and longer reaction times in the incongruent stimulus task independently of gender. For the congruent stimulus task of the Stroop test, the stressed males presented a higher rate of errors than the non-stressed males and a longer reaction time than the stressed females. After the acute mental stressor, the non-stressed male group showed an increase in salivary alpha-amylase activity, which returned to the initial values five minutes after the test; this ANS reactivity was not observed in the chronically stressed male subjects. The ANS responses of the non-stressed vs stressed female groups were not different prior to or after the Stroop test. This study is the first to demonstrate a blunted reactivity of the ANS when male subjects with chronic psychological stress were subjected to an acute mental stressor, and this change could contribute to impairments in cognitive performance. PMID:25807003

Chronic stress induces a hyporeactivity of the autonomic nervous system in response to acute mental stressor and impairs cognitive performance in business executives.

PubMed

Teixeira, Renata Roland; Díaz, Miguel Mauricio; Santos, Tatiane Vanessa da Silva; Bernardes, Jean Tofoles Martins; Peixoto, Leonardo Gomes; Bocanegra, Olga Lucia; Neto, Morun Bernardino; Espindola, Foued Salmen

2015-01-01

The present study examined the incidence of chronic stress in business executives (109 subjects: 75 male and 34 female) and its relationship with cortisol levels, cognitive performance, and autonomic nervous system (ANS) reactivity after an acute mental stressor. Blood samples were collected from the subjects to measure cortisol concentration. After the sample collection, the subjects completed the Lipp Inventory of Stress Symptoms for Adults and the Stroop Color-Word Test to evaluate stress and cognitive performance levels, respectively. Saliva samples were collected prior to, immediately after, and five minutes after the test. The results revealed that 90.1% of the stressed subjects experienced stress phases that are considered chronic stress. At rest, the subjects with chronic stress showed higher cortisol levels, and no gender differences were observed. No differences were found between the stressed and non-stressed subjects regarding salivary amylase activity prior to test. Chronic stress also impaired performance on the Stroop test, which revealed higher rates of error and longer reaction times in the incongruent stimulus task independently of gender. For the congruent stimulus task of the Stroop test, the stressed males presented a higher rate of errors than the non-stressed males and a longer reaction time than the stressed females. After the acute mental stressor, the non-stressed male group showed an increase in salivary alpha-amylase activity, which returned to the initial values five minutes after the test; this ANS reactivity was not observed in the chronically stressed male subjects. The ANS responses of the non-stressed vs stressed female groups were not different prior to or after the Stroop test. This study is the first to demonstrate a blunted reactivity of the ANS when male subjects with chronic psychological stress were subjected to an acute mental stressor, and this change could contribute to impairments in cognitive performance.

"Omics" of maize stress response for sustainable food production: opportunities and challenges.

PubMed

Gong, Fangping; Yang, Le; Tai, Fuju; Hu, Xiuli; Wang, Wei

2014-12-01

Maize originated in the highlands of Mexico approximately 8700 years ago and is one of the most commonly grown cereal crops worldwide, followed by wheat and rice. Abiotic stresses (primarily drought, salinity, and high and low temperatures), together with biotic stresses (primarily fungi, viruses, and pests), negatively affect maize growth, development, and eventually production. To understand the response of maize to abiotic and biotic stresses and its mechanism of stress tolerance, high-throughput omics approaches have been used in maize stress studies. Integrated omics approaches are crucial for dissecting the temporal and spatial system-level changes that occur in maize under various stresses. In this comprehensive analysis, we review the primary types of stresses that threaten sustainable maize production; underscore the recent advances in maize stress omics, especially proteomics; and discuss the opportunities, challenges, and future directions of maize stress omics, with a view to sustainable food production. The knowledge gained from studying maize stress omics is instrumental for improving maize to cope with various stresses and to meet the food demands of the exponentially growing global population. Omics systems science offers actionable potential solutions for sustainable food production, and we present maize as a notable case study.

Negative life events and symptoms of depression and anxiety: stress causation and/or stress generation.

PubMed

Phillips, Anna C; Carroll, Douglas; Der, Geoff

2015-01-01

Stressful life events are known to contribute to development of depression; however, it is possible this link is bidirectional. The present study examined whether such stress generation effects are greater than the effects of stressful life events on depression, and whether stress generation is also evident with anxiety. Participants were two large age cohorts (N = 732 aged 44 years; N = 705 aged 63 years) from the West of Scotland Twenty-07 study. Stressful life events, depression, and anxiety symptoms were measured twice five years apart. Cross-lagged panel analysis examined the mutual influences of stressful life events on depression and on anxiety over time. Life events predicted later depressive symptomatology (p = .01), but the depression predicting life events relationship was less strong (p = .06), whereas earlier anxiety predicted life events five years later (p = .001). There was evidence of sex differences in the extent to which life events predicted later anxiety. This study provides evidence of stress causation for depression and weaker evidence for stress generation. In contrast, there was strong evidence of stress generation for anxiety but weaker evidence for stress causation, and that differed for men and women.

Negative life events and symptoms of depression and anxiety: Stress causation and/or stress generation

PubMed Central

Phillips, Anna C.; Carroll, Douglas; Der, Geoff

2016-01-01

Background and Objectives Stressful life events are known to contribute to development of depression, however, it is possible this link is bi-directional. The present study examined whether such stress generation effects are greater than the effects of stressful life events on depression, and whether stress generation is also evident with anxiety. Design Participants were two large age cohorts (N = 732 aged 44 years; N = 705 aged 63 years) from the West of Scotland Twenty-07 study. Methods Stressful life events, depression and anxiety symptoms were measured twice five years apart. Cross-lagged panel analysis examined the mutual influences of stressful life events on depression and on anxiety over time. Results Life events predicted later depressive symptomatology (p = .01), but the depression predicting life events relationship was less strong (p = .06), whereas earlier anxiety predicted life events five years later (p = .001). There was evidence of sex differences in the extent to which life events predicted later anxiety. Conclusions This study provides evidence of stress causation for depression and weaker evidence for stress generation. In contrast, there was strong evidence of stress generation for anxiety but weaker evidence for stress causation, and that differed for men and women. PMID:25572915

“Omics” of Maize Stress Response for Sustainable Food Production: Opportunities and Challenges

PubMed Central

Gong, Fangping; Yang, Le; Tai, Fuju; Hu, Xiuli

2014-01-01

Abstract Maize originated in the highlands of Mexico approximately 8700 years ago and is one of the most commonly grown cereal crops worldwide, followed by wheat and rice. Abiotic stresses (primarily drought, salinity, and high and low temperatures), together with biotic stresses (primarily fungi, viruses, and pests), negatively affect maize growth, development, and eventually production. To understand the response of maize to abiotic and biotic stresses and its mechanism of stress tolerance, high-throughput omics approaches have been used in maize stress studies. Integrated omics approaches are crucial for dissecting the temporal and spatial system-level changes that occur in maize under various stresses. In this comprehensive analysis, we review the primary types of stresses that threaten sustainable maize production; underscore the recent advances in maize stress omics, especially proteomics; and discuss the opportunities, challenges, and future directions of maize stress omics, with a view to sustainable food production. The knowledge gained from studying maize stress omics is instrumental for improving maize to cope with various stresses and to meet the food demands of the exponentially growing global population. Omics systems science offers actionable potential solutions for sustainable food production, and we present maize as a notable case study. PMID:25401749

Stress-Induced Depression Is Alleviated by Aerobic Exercise Through Up-Regulation of 5-Hydroxytryptamine 1A Receptors in Rats.

PubMed

Kim, Tae Woon; Lim, Baek Vin; Baek, Dongjin; Ryu, Dong-Soo; Seo, Jin Hee

2015-03-01

Stress is associated with depression, which induces many psychiatric disorders. Serotonin, also known as 5-hydroxy-tryptamine (5-HT), acts as a biochemical messenger and regulator in the brain. It also mediates several important physiological functions. Depression is closely associated with an overactive bladder. In the present study, we investigated the effect of treadmill exercise on stress-induced depression while focusing on the expression of 5-HT 1A (5-H1A) receptors in the dorsal raphe. Stress was induced by applying a 0.2-mA electric foot shock to rats. Each set of electric foot shocks comprised a 6-second shock duration that was repeated 10 times with a 30-second interval. Three sets of electric foot shocks were applied each day for 7 days. For the confirmation of depressive state, a forced swimming test was performed. To visualize the expression of 5-HT and tryptophan hydroxylase (TPH), immunohistochemistry for 5-HT and TPH in the dorsal raphe was performed. Expression of 5-H1A receptors was determined by western blot analysis. A depressive state was induced by stress, and treadmill exercise alleviated the depression symptoms in the stress-induced rats. Expressions of 5-HT, TPH, and HT 1A in the dorsal raphe were reduced by the induction of stress. Treadmill exercise increased 5-HT, TPH, and HT 1A expressions in the stress-induced rats. Treadmill exercise enhanced 5-HT synthesis through the up-regulation of 5-HT1A receptors, and improved the stress-induced depression. In the present study, treadmill exercise improved depression symptoms by enhancing 5-HT1A receptor expression. The present results suggest that treadmill exercise might be helpful for the alleviation of overactive bladder and improve sexual function.

Tectonic stress pattern in the Chinese Mainland from the inversion of focal mechanism data

NASA Astrophysics Data System (ADS)

Wei, Ju; Weifeng, Sun; Xiaojing, Ma

2017-04-01

The tectonic stress pattern in the Chinese Mainland and kinematic models have been subjected to much debate. In the past several decades, several tectonic stress maps have been figured out; however, they generally suffer a poor time control. In the present study, 421 focal mechanism data up to January 2010 were compiled from the Global/Harvard CMT catalogue, and 396 of them were grouped into 23 distinct regions in function of geographic proximity. Reduced stress tensors were obtained from formal stress inversion for each region. The results indicated that, in the Chinese Mainland, the directions of maximum principal stress were ˜NE-SW-trending in the northeastern region, ˜NEE-SWW-trending in the North China region, ˜N-S-trending in western Xinjiang, southern Tibet and the southern Yunnan region, ˜NNE-SSW-trending in the northern Tibet and Qinghai region, ˜NW-SE-trending in Gansu region, and ˜E-W-trending in the western Sichuan region. The average tectonic stress regime was strike-slip faulting (SS) in the eastern Chinese Mainland and northern Tibet region, normal faulting (NF) in the southern Tibet, western Xinjiang and Yunnan region, and thrust faulting (TF) in most regions of Xinjiang, Qinghai and Gansu. The results of the present study combined with GPS velocities in the Chinese Mainland supported and could provide new insights into previous tectonic models (e.g., the extrusion model). From the perspective of tectonics, the mutual actions among the Eurasian plate, Pacific plate and Indian plate caused the present-day tectonic stress field in the Chinese Mainland.

Chewing gum modifies state anxiety and alertness under conditions of social stress.

PubMed

Sketchley-Kaye, Kathryn; Jenks, Rebecca; Miles, Christopher; Johnson, Andrew J

2011-11-01

The finding that chewing gum can moderate state anxiety under conditions of acute stress has proved difficult to replicate. The present study examines the extent to which chewing gum can moderate state anxiety under conditions of acute social stress. In a between-participants design, 36 participants completed a task comprising a mock job interview (a variation on the Trier Social Stress Task, which included a mental arithmetic component) while either chewing gum or without chewing gum. Self-rated measures of mood and anxiety were taken at baseline, after a 10-minute presentation preparation stage, after the 10-minute presentation, and following a 5-minute recovery stage. Post-presentation measures reflected increased state anxiety and decreased self-rated calmness and contentedness. Chewing gum attenuated the rise in state anxiety while increasing self-rated alertness. Chewing gum did not affect contentedness or calmness. The findings indicate that chewing gum can act to reduce anxiety under conditions of acute social stress: a finding consistent with Scholey et al. Furthermore, the data add to the growing body of literature demonstrating that chewing gum can increase alertness.

Regulation of the Adrenal Cortex Function During Stress

NASA Technical Reports Server (NTRS)

Soliman, K. F. A.

1978-01-01

A proposal to study the function of the adrenal gland in the rat during stress is presented. In the proposed project, three different phases of experimentation will be undertaken. The first phase includes establishment of the circadian rhythm of both brain amines and glucocoticoids, under normal conditions and under chronic and acute stressful conditions. The second phase includes the study of the pharmacokinetics of glucocorticoid binding under normal and stress conditions. The third phase includes brain uptake and binding under different experimental conditions. In the outlined experiments brain biogenic amines will be evaluated, adrenal functions will be measured and stress effect on those parameters will be studied. It is hoped that this investigation can explain some of the complex relationships between the brain neurotransmitter and adrenal function.

The sociocultural dynamics of mass hysteria: a case study of social conflict in West Malaysia.

PubMed

Lee, R L; Ackerman, S E

1980-02-01

This discussion of an episode of mass hysteria in a Malay college in West Malaysia examines stress and conflict in relation to the interpretive process within a specific social setting. Unlike previous studies, which conceptualize mass hysteria as a cathartic response to accumulated stress, the present study treats stress as a matter of definition in a specific sociocultural context rather than as an objective given from which predictions can be made. Objections are raised to the logic of explanations that attribute mass hysteria to environmental stress. What is of concern is how meanings are assigned to events that are experienced as stressful, how participants and observers explain these events, and the consequences that follow from their interpretations.

[Stress and autonomic dysregulation in patients with fibromyalgia syndrome].

PubMed

Friederich, H-C; Schellberg, D; Mueller, K; Bieber, C; Zipfel, S; Eich, W

2005-06-01

The aim of the present study was to evaluate to what extent the orthostatic dysregulation of FMS patients can be attributed primarily to reduced baroreceptor-mediated activation of the sympathetic nervous system and whether a hyporeactive sympathetic nervous system can also be confirmed for mental stress. A total of 28 patients with primary FMS were examined and compared with 15 healthy subjects. Diagnostic investigations of the autonomic nervous system were based on measuring HRV in frequency range and assessing spontaneous baroreflex sensitivity (sBRS) under mental stress and passive orthostatism. Both under orthostatic and mental stress FMS patients exhibited reduced activation of the sympathetic nervous system as measured by the spectral power of HRV in the low-frequency range and the mean arterial blood pressure or heart rate. The present study provided no indications for dysregulation of sBRS. The results obtained confirm the hypothesis of a hyporeactive stress system in FMS patients for both peripherally and centrally mediated stimulation of the sympathetic nervous system.

Stress and its Impact on the Neurocognitive Performance of Australian Nurses.

PubMed

Lees, Ty; Lal, Sara

2017-02-01

Nurses function inside a particularly stressful occupation that requires the provision of continuous care to individuals who are often in great need. Stress has been shown to impair performance and specifically shown to impair nursing quality. However, we do not yet know how stress influences the cognitive performance of nurses, and hence, the present study investigated the associations between stress and cognitive performance in nurses using electroencephalography and administered cognitive assessments. Thirty-six nurses (34 women) of mean age 37.77 ± 11.40 years were recruited. Stress was examined using the Lifestyle Appraisal Questionnaire. Broad spectrum electroencephalogram activity at positions Fp1, Fp2, C3 and C4 was recorded for a 5-min baseline and active phase to physiologically assess cognitive performance. Additionally, the Mini-Mental State Exam and Cognistat were also used to measure cognitive performance. Assessed cognitive performance was not associated to stress, however, lifestyle factors, as well as a number of the examined cognitive electroencephalographic variables including changes in theta, alpha activity and gamma reactivity were. Definitively determining how stress affects the cognitive performance of nurses requires additional research; the present study forms a foundation from which future research can further expand the examination of stress exposure in nurses. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Effects of prenatal stress and neonatal handling on anxiety, spatial learning and serotonergic system of male offspring mice.

PubMed

Akatsu, Shigemi; Ishikawa, Chihiro; Takemura, Kaori; Ohtani, Akiko; Shiga, Takashi

2015-12-01

Environmental factors during perinatal period have various effects on behavior. The present study examined the effects of prenatal stress and neonatal handling on anxiety and spatial learning of offspring. Prenatal stress increased anxiety-related behavior of adult offspring, whereas neonatal handling had no effect. In contrast, spatial learning was not affected by prenatal stress, but improved by neonatal handling in both prenatally stressed and non-stressed mice. Next, to elucidate possible brain mechanisms mediating effects of environmental factors on behavior, we focused on serotonin (5-HT) system in the frontal cortex and hippocampus which is involved in anxiety and learning. We examined effects of environmental factors on the mRNA expression of 5-HT1A, 5-HT2A and 5-HT2C receptors in the frontal cortex and hippocampus during postnatal period and adulthood. Both prenatal stress and neonatal handling altered the mRNA expression of 5-HT receptors. These effects were dependent on environmental factors, brain regions and developmental stages. In summary, the present study revealed that prenatal stress and neonatal handling had differential effects on anxiety and spatial learning of offspring, and concomitantly the expression of 5-HT receptors. It was also shown that the effects of prenatal stress on 5-HT system were recovered partially by neonatal handling. Copyright © 2015 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

Transactional relations between caregiving stress, executive functioning, and problem behavior from early childhood to early adolescence

PubMed Central

LaGasse, Linda L.; Conradt, Elisabeth; Karalunas, Sarah L.; Dansereau, Lynne M.; Butner, Jonathan E.; Shankaran, Seetha; Bada, Henrietta; Bauer, Charles R.; Whitaker, Toni M.; Lester, Barry M.

2016-01-01

Developmental psychopathologists face the difficult task of identifying the environmental conditions that may contribute to early childhood behavior problems. Highly stressed caregivers can exacerbate behavior problems, while children with behavior problems may make parenting more difficult and increase caregiver stress. Unknown is: (1) how these transactions originate, (2) whether they persist over time to contribute to the development of problem behavior and (3) what role resilience factors, such as child executive functioning, may play in mitigating the development of problem behavior. In the present study, transactional relations between caregiving stress, executive functioning, and behavior problems were examined in a sample of 1,388 children with prenatal drug exposures at three developmental time points: early childhood (birth-age 5), middle childhood (ages 6 to 9), and early adolescence (ages 10 to 13). Transactional relations differed between caregiving stress and internalizing versus externalizing behavior. Targeting executive functioning in evidence-based interventions for children with prenatal substance exposure who present with internalizing problems and treating caregiving psychopathology, depression, and parenting stress in early childhood may be particularly important for children presenting with internalizing behavior. PMID:27427803

Computational Modeling of Morphogenesis Regulated by Mechanical Feedback

PubMed Central

Ramasubramanian, Ashok; Taber, Larry A.

2008-01-01

Mechanical forces cause changes in form during embryogenesis and likely play a role in regulating these changes. This paper explores the idea that changes in homeostatic tissue stress (target stress), possibly modulated by genes, drive some morphogenetic processes. Computational models are presented to illustrate how regional variations in target stress can cause a range of complex behaviors involving the bending of epithelia. These models include growth and cytoskeletal contraction regulated by stress-based mechanical feedback. All simulations were carried out using the commercial finite element code ABAQUS, with growth and contraction included by modifying the zero-stress state in the material constitutive relations. Results presented for bending of bilayered beams and invagination of cylindrical and spherical shells provide insight into some of the mechanical aspects that must be considered in studying morphogenetic mechanisms. PMID:17318485

The Relations Between Maternal Prenatal Anxiety or Stress and Child's Early Negative Reactivity or Self-Regulation: A Systematic Review.

PubMed

Korja, Riikka; Nolvi, Saara; Grant, Kerry Ann; McMahon, Cathy

2017-12-01

In the present review, we examine the association between maternal prenatal stress or anxiety and children's early negative reactivity or self-regulation. The review includes 32 studies that focus on pregnancy-related anxiety, state or trait anxiety, perceived stress, and stressful life events in relation to child's crying, temperament, or behavior during the first 2 years of life. We searched four electronic databases and 32 studies were selected based on the inclusion criteria. Twenty-three studies found an association between maternal prenatal anxiety or stress and a child's negative reactivity or self-regulation, and typically the effect sizes varied from low to moderate. The association was found regardless of the form of prenatal stress or anxiety and the trimester in which the prenatal stress or anxiety was measured. In conclusion, several forms of prenatal anxiety and stress may increase the risk of emotional and self-regulatory difficulties during the first 2 years of life.

Stressful Life Events and Depression Symptoms: The Effect of Childhood Emotional Abuse on Stress Reactivity

PubMed Central

Shapero, Benjamin G.; Black, Shimrit K.; Liu, Richard T.; Klugman, Joshua; Bender, Rachel E.; Abramson, Lyn Y.; Alloy, Lauren B.

2013-01-01

Objective Stressful life events are associated with an increase in depressive symptoms and the onset of major depression. Importantly, research has shown that the role of stress changes over the course of depression. The present study extends the current literature by examining the effects of early life stress on emotional reactivity to current stressors. Method In a multiwave study (N = 281, mean age = 18.76; 68% female), we investigated the proximal changes that occur in depressive symptoms when individuals are faced with life stress and whether a history of childhood emotional abuse moderates this relationship. Results Results support the stress sensitivity hypothesis for early emotional abuse history. Individuals with greater childhood emotional abuse severity experienced greater increases in depressive symptoms when confronted with current dependent stressors, controlling for childhood physical and sexual abuse. Conclusions This study highlights the importance of emotional abuse as an indicator for reactivity to stressful life events. PMID:23800893

[Comparative pathology of early stress-induced changes in the duodenal mucosa in laboratory rats and in humans].

PubMed

Peychl, L; Brejcha, A

2003-01-01

Our presentation comprises results of two studies: The first was an experimental investigation of 60 Wistar-strain rats used in a toxicological study. The other part analysed stress changes in the duodenal mucosa in the human autopsy material. Both humans and rats had been exposed to stress and showed similar histological changes. In the rats the same duodenal lesions were present both in the test group and the control animals in the toxicological study. Lesions consisted of oedema of the duodenal villi and erosions in the tips of the villi. We believe that in the experimental group the stress was caused by restraining the animals by daily introduction of the gastric metallic tube, by taking blood from the retrobulbar plexus, and by anaesthesia. The autopsy study comprised 35 cases displaying congestion and macroscopically recognizable multifocal bleeding into the duodenal mucosal folds. The microscopic investigation revealed bleeding into the mucosal villi and small erosions. In some cases there were cuneiform mucosal infarcts extending into the submucosa. In the humans, severe cardiovascular diseases and circulatory disturbances represented the main causes of the stress. Local hypoxia and gastric juice acidity were involved in the pathogenesis of the duodenal mucosal changes.

Building a Family Systems Model to Promote Adherence to PTSD Treatment

DTIC Science & Technology

2015-10-01

stress disorder ( PTSD ) result in clinically significant symptom relief for many patients and are recommended as first-line treatments by the VA/DOD...findings at the annual meeting of the International Society of Traumatic Stress Studies (see citations below) and at an In Progress Review on 9/11...presentation at the 30th annual meeting of the International Society of Traumatic Stress Studies, Miami, Florida. ABSTRACT: We examined the role of family

Genome-Wide Identification and Comprehensive Expression Profiling of Ribosomal Protein Small Subunit (RPS) Genes and their Comparative Analysis with the Large Subunit (RPL) Genes in Rice

PubMed Central

Saha, Anusree; Das, Shubhajit; Moin, Mazahar; Dutta, Mouboni; Bakshi, Achala; Madhav, M. S.; Kirti, P. B.

2017-01-01

Ribosomal proteins (RPs) are indispensable in ribosome biogenesis and protein synthesis, and play a crucial role in diverse developmental processes. Our previous studies on Ribosomal Protein Large subunit (RPL) genes provided insights into their stress responsive roles in rice. In the present study, we have explored the developmental and stress regulated expression patterns of Ribosomal Protein Small (RPS) subunit genes for their differential expression in a spatiotemporal and stress dependent manner. We have also performed an in silico analysis of gene structure, cis-elements in upstream regulatory regions, protein properties and phylogeny. Expression studies of the 34 RPS genes in 13 different tissues of rice covering major growth and developmental stages revealed that their expression was substantially elevated, mostly in shoots and leaves indicating their possible involvement in the development of vegetative organs. The majority of the RPS genes have manifested significant expression under all abiotic stress treatments with ABA, PEG, NaCl, and H2O2. Infection with important rice pathogens, Xanthomonas oryzae pv. oryzae (Xoo) and Rhizoctonia solani also induced the up-regulation of several of the RPS genes. RPS4, 13a, 18a, and 4a have shown higher transcript levels under all the abiotic stresses, whereas, RPS4 is up-regulated in both the biotic stress treatments. The information obtained from the present investigation would be useful in appreciating the possible stress-regulatory attributes of the genes coding for rice ribosomal small subunit proteins apart from their functions as house-keeping proteins. A detailed functional analysis of independent genes is required to study their roles in stress tolerance and generating stress- tolerant crops. PMID:28966624

Hunger, inhibitory control and distress-induced emotional eating.

PubMed

van Strien, Tatjana; Ouwens, Machteld A; Engel, Carmen; de Weerth, Carolina

2014-08-01

Self-reported emotional eating has been found to significantly moderate distress-induced food intake, with low emotional eaters eating less after a stress task than after a control task and high emotional eaters eating more. The aim of the present study was to explore possible underlying mechanisms by assessing possible associations with (1) ability to experience the typical post-stress reduction of hunger and (2) inhibitory control. We studied these effects in 54 female students who were preselected on the basis of extremely high or low scores on an emotional eating questionnaire. Using a within subject design we measured the difference of actual food or snack intake after a control or a stress task (Trier Social Stress Test). As expected, the moderator effect of emotional eating on distress-induced food intake was found to be only present in females with a failure to report the typical reduction of hunger immediately after a stress task (an a-typical hunger stress response). Contrary to our expectations, this moderator effect of emotional eating was also found to be only present in females with high ability to stop motor impulses (high inhibitory control). These findings suggest that an a-typical hunger stress response but not poor inhibitory control may underlie the moderator effect of emotional eating on distress-induced food intake. However, inhibitory control may play a role whether or not there is a moderator effect of self-reported emotional eating on distress-induced food intake. Copyright © 2014 Elsevier Ltd. All rights reserved.

Intestinal microbiome-gut-brain axis and irritable bowel syndrome.

PubMed

Moser, Gabriele; Fournier, Camille; Peter, Johannes

2018-03-01

Psychological comorbidity is highly present in irritable bowel syndrome (IBS). Recent research points to a role of intestinal microbiota in visceral hypersensitivity, anxiety, and depression. Increased disease reactivity to psychological stress has been described too. A few clinical studies have attempted to identify features of dysbiosis in IBS. While animal studies revealed strong associations between stress and gut microbiota, studies in humans are rare. This review covers the most important studies on intestinal microbial correlates of psychological and clinical features in IBS, including stress, anxiety, and depression.

Immune System Dysregulation, Viral Reactivation and Stress During Short-Duration Space Flight

NASA Technical Reports Server (NTRS)

Crucian, Brian; Mehta, Satish; Stowe, Raymond; Uchakin, Peter; Quiriarte, Heather; Pierson, Duane; Sams, Clarence

2010-01-01

This slide presentation reviews a study that was conducted to ascertain if the immune system dysregulation, viral reactivation and stress from short duration space flight were a result of the stress of landing and readjustment to gravity. The objectives of the study were to replace several recent immune studies with one comprehensive study that will include in-flight sampling; address lack of in-flight data: (i.e., determine the in-flight status of immunity, physiological stress, viral immunity/reactivation); determine the clinical risk related to immune dysregulation for exploration class spaceflight; and determine the appropriate monitoring strategy for spaceflight-associated immune dysfunction, that could be used for the evaluation of countermeasures.

Estimation of Stresses in a Dry Sand Layer Tested on Shaking Table

NASA Astrophysics Data System (ADS)

Sawicki, Andrzej; Kulczykowski, Marek; Jankowski, Robert

2012-12-01

Theoretical analysis of shaking table experiments, simulating earthquake response of a dry sand layer, is presented. The aim of such experiments is to study seismic-induced compaction of soil and resulting settlements. In order to determine the soil compaction, the cyclic stresses and strains should be calculated first. These stresses are caused by the cyclic horizontal acceleration at the base of soil layer, so it is important to determine the stress field as function of the base acceleration. It is particularly important for a proper interpretation of shaking table tests, where the base acceleration is controlled but the stresses are hard to measure, and they can only be deduced. Preliminary experiments have shown that small accelerations do not lead to essential settlements, whilst large accelerations cause some phenomena typical for limit states, including a visible appearance of slip lines. All these problems should be well understood for rational planning of experiments. The analysis of these problems is presented in this paper. First, some heuristic considerations about the dynamics of experimental system are presented. Then, the analysis of boundary conditions, expressed as resultants of respective stresses is shown. A particular form of boundary conditions has been chosen, which satisfies the macroscopic boundary conditions and the equilibrium equations. Then, some considerations are presented in order to obtain statically admissible stress field, which does not exceed the Coulomb-Mohr yield conditions. Such an approach leads to determination of the limit base accelerations, which do not cause the plastic state in soil. It was shown that larger accelerations lead to increase of the lateral stresses, and the respective method, which may replace complex plasticity analyses, is proposed. It is shown that it is the lateral stress coefficient K0 that controls the statically admissible stress field during the shaking table experiments.

Integrated metabolomic and proteomic analysis reveals systemic responses of Rubrivivax benzoatilyticus JA2 to aniline stress.

PubMed

Mujahid, Md; Prasuna, M Lakshmi; Sasikala, Ch; Ramana, Ch Venkata

2015-02-06

Aromatic amines are widely distributed in the environment and are major environmental pollutants. Although degradation of aromatic amines is well studied in bacteria, physiological adaptations and stress response to these toxic compounds is not yet fully understood. In the present study, systemic responses of Rubrivivax benzoatilyticus JA2 to aniline stress were deciphered using metabolite and iTRAQ-labeled protein profiling. Strain JA2 tolerated high concentrations of aniline (30 mM) with trace amounts of aniline being transformed to acetanilide. GC-MS metabolite profiling revealed aniline stress phenotype wherein amino acid, carbohydrate, fatty acid, nitrogen metabolisms, and TCA (tricarboxylic acid cycle) were modulated. Strain JA2 responded to aniline by remodeling the proteome, and cellular functions, such as signaling, transcription, translation, stress tolerance, transport and carbohydrate metabolism, were highly modulated. Key adaptive responses, such as transcription/translational changes, molecular chaperones to control protein folding, and efflux pumps implicated in solvent extrusion, were induced in response to aniline stress. Proteo-metabolomics indicated extensive rewiring of metabolism to aniline. TCA cycle and amino acid catabolism were down-regulated while gluconeogenesis and pentose phosphate pathways were up-regulated, leading to the synthesis of extracellular polymeric substances. Furthermore, increased saturated fatty acid ratios in membranes due to aniline stress suggest membrane adaptation. The present study thus indicates that strain JA2 employs multilayered responses: stress response, toxic compound tolerance, energy conservation, and metabolic rearrangements to aniline.

Oxidative stress in schizophrenia: a case-control study on the effects on social cognition and neurocognition.

PubMed

Gonzalez-Liencres, Cristina; Tas, Cumhur; Brown, Elliot C; Erdin, Soner; Onur, Ece; Cubukcoglu, Zeynep; Aydemir, Omer; Esen-Danaci, Aysen; Brüne, Martin

2014-09-24

Schizophrenia is a debilitating mental disorder that presents impairments in neurocognition and social cognition. Several studies have suggested that the etiology of schizophrenia can be partly explained by oxidative stress. However, our knowledge about the implications of oxidative stress on illness-related cognitive deficits is still far from being clear. The aim of this work was to study the role of oxidative stress molecules on social cognition and neurocognition in patients with schizophrenia. We assessed the peripheral levels of several molecules associated with oxidative stress, namely nitric oxide (NO), malondialdehyde (MDA), glutathione (GSH), homocysteine, superoxide dismutase (SOD) and neurotrophin 4/5 (NT4/5), in forty-one patients with schizophrenia and forty-three healthy participants. A battery of tests to measure neurocognition and social cognition was also administered to the schizophrenia group. We found that the schizophrenia group presented substantially higher levels of oxidative stress than the control group, as revealed by elevated quantities of the pro-oxidants NO and MDA, and decreased levels of the antioxidants GSH, SOD and NT4/5. Interestingly, the levels of NT4/5, which have been shown to have antioxidant effects, correlated with executive functioning, as measured by two distinct tests (WCST and TMT). However, social cognition and symptom severity were not found to be associated with oxidative stress. We propose a protective role of NT4/5 against oxidative stress, which appears to have a potentially beneficial impact on neurocognition in schizophrenia.

Allowable stress in piles.

DOT National Transportation Integrated Search

1983-12-01

"This study presents methods for establishing allowable stresses in steel, concrete, and timber piles using load/resistance factor concepts. These methods take into account not only the material properties of the pile itself but also the individual e...

Dream Content and Adaptation to a Stressful Situation

ERIC Educational Resources Information Center

De Koninck, Joseph M.; Koulack, David

1975-01-01

The present study considered whether it is better to dream about a stressful presleep experience and have anxious dreams, or is it better to dream about something else and have pleasant dreams. (Author/RK)

Cracking mechanism of shale cracks during fracturing

NASA Astrophysics Data System (ADS)

Zhao, X. J.; Zhan, Q.; Fan, H.; Zhao, H. B.; An, F. J.

2018-06-01

In this paper, we set up a model for calculating the shale fracture pressure on the basis of Huang’s model by the theory of elastic-plastic mechanics, rock mechanics and the application of the maximum tensile stress criterion, which takes into account such factors as the crustal stress field, chemical field, temperature field, tectonic stress field, the porosity of shale and seepage of drilling fluid and so on. Combined with the experimental data of field fracturing and the experimental results of three axis compression of shale core with different water contents, the results show that the error between the present study and the measured value is 3.85%, so the present study can provide technical support for drilling engineering.

Evaluating the irradiation effects on the elastic properties of miniature monolithic SiC tubular specimens

NASA Astrophysics Data System (ADS)

Singh, G.; Koyanagi, T.; Petrie, C.; Terrani, K.; Katoh, Y.

2018-02-01

The initial results of a post-irradiation examination study conducted on CVD SiC tubular specimens irradiated under a high radial heat flux are presented herein. The elastic moduli were found to decrease more than that estimated based on previous studies. The significant decreases in modulus are attributed to the cracks present in the specimens. The stresses in the specimens, calculated through finite element analyses, were found to be greater than the expected strength of irradiated specimens, indicating that the irradiation-induced stresses caused these cracks. The optical microscopy images and predicted stress distributions indicate that the cracks initiated at the inner surface and propagated outward.

Resilience to chronic stress is mediated by hippocampal brain-derived neurotrophic factor.

PubMed

Taliaz, Dekel; Loya, Assaf; Gersner, Roman; Haramati, Sharon; Chen, Alon; Zangen, Abraham

2011-03-23

Chronic stress is a trigger for several psychiatric disorders, including depression; however, critical individual differences in resilience to both the behavioral and the neurochemical effects of stress have been reported. A prominent mechanism by which the brain reacts to acute and chronic stress is activation of the hypothalamic-pituitary-adrenal (HPA) axis, which is inhibited by the hippocampus via a polysynaptic circuit. Alterations in secretion of stress hormones and levels of brain-derived neurotrophic factor (BDNF) in the hippocampus were implicated in depression and the effects of antidepressant medications. However, the potential role of hippocampal BDNF in behavioral resilience to chronic stress and in the regulation of the HPA axis has not been evaluated. In the present study, Sprague Dawley rats were subjected to 4 weeks of chronic mild stress (CMS) to induce depressive-like behaviors after lentiviral vectors were used to induce localized BDNF overexpression or knockdown in the hippocampus. The behavioral outcome was measured during 3 weeks after the CMS procedure, then plasma samples were taken for measurements of corticosterone levels, and finally hippocampal tissue was taken for BDNF measurements. We found that hippocampal BDNF expression plays a critical role in resilience to chronic stress and that reduction of hippocampal BDNF expression in young, but not adult, rats induces prolonged elevations in corticosterone secretion. The present study describes a mechanism for individual differences in responses to chronic stress and implicates hippocampal BDNF in the development of neural circuits that control adequate stress adaptations.

The Structural Model of Spirituality and Psychological Well-Being for Pregnancy-Specific Stress.

PubMed

Dolatian, Mahrokh; Mahmoodi, Zohreh; Dilgony, Taibeh; Shams, Jamal; Zaeri, Farid

2017-12-01

Women experience different types of stress in their lifetime. The present study was conducted to examine the structural model of spirituality and psychological well-being for pregnancy-specific stress. The present descriptive correlational study was conducted on 450 pregnant Iranian women (150 women from each trimester) in Dehdasht city in 2015. Data were collected using the personal-social questionnaire, the pregnancy-specific stress questionnaire, the spirituality questionnaire and the psychological well-being questionnaire and were then analyzed in SPSS-16 and Lisrel-8.8 for carrying out a path analysis. The fit indices of the model indicate the good fit and high compatibility of the model and rational relationships between the variables (GFI = 0.94, NFI = 0.85, CFI = 0.94 and RMSEA = 0.048). Of the variables that affected pregnancy-specific stress through both paths, spirituality had a positive effect (B = 0.11) and the personal-social variable a negative effect (B = -0.37). Psychological well-being affected pregnancy-specific stress negatively and directly and through one path only (B = -0.59). The results obtained through the model confirm the effect of spirituality and psychological well-being in reducing pregnancy-specific stress. Given that handling stress has a major role in the quality of daily life in pregnant women, stress management skills are recommended to be promoted among pregnant women so as to mitigate stress and its negative consequences.

The frequency of perceived stress, anxiety, and depression in patients with common pathologies affecting voice.

PubMed

Dietrich, Maria; Verdolini Abbott, Katherine; Gartner-Schmidt, Jackie; Rosen, Clark A

2008-07-01

The study's objectives were to investigate (1) the frequency of perceived stress, anxiety, and depression for patients with common voice disorders, (2) the distribution of these variables by diagnosis, and (3) the distribution of the variables by gender. Retrospective data were derived from self-report questionnaires assessing recent stress (Perceived Stress Scale-10), anxiety, and depression (Hospital Anxiety and Depression Scale) in a cohort of new patients presenting to a voice clinic. Data are presented on 160 patients with muscle tension dysphonia (MTD), benign vocal fold lesions, paradoxical vocal fold movement disorder (PVFMD), or glottal insufficiency. Pooled data indicated that average stress, anxiety, and depression scores were similar to those found for the healthy population. However, 25.0%, 36.9%, and 31.2% of patients showed elevated stress, anxiety, and depression scores, respectively, compared to norms. Patients with PVFMD had the most frequent occurrence-and patients with glottal insufficiency had the least frequent occurrence of elevated stress, anxiety, and depression. Stress and depression were more common with MTD than with lesions, whereas reverse results were obtained for anxiety. More females than males had elevated stress, anxiety, and depression scores. The data are consistent with suggestions that stress, anxiety, and depression may be common among some patients with PVFMD, MTD, and vocal fold lesions and more common for women than men. However, individual variability in the data set was large. Further studies should evaluate the specific role of these conditions for selected categories of voice disorders in susceptible individuals.

Full-field stress determination in photoelasticity with phase shifting technique

NASA Astrophysics Data System (ADS)

Guo, Enhai; Liu, Yonggang; Han, Yongsheng; Arola, Dwayne; Zhang, Dongsheng

2018-04-01

Photoelasticity is an effective method for evaluating the stress and its spatial variations within a stressed body. In the present study, a method to determine the stress distribution by means of phase shifting and a modified shear-difference is proposed. First, the orientation of the first principal stress and the retardation between the principal stresses are determined in the full-field through phase shifting. Then, through bicubic interpolation and derivation of a modified shear-difference method, the internal stress is calculated from the point with a free boundary along its normal direction. A method to reduce integration error in the shear difference scheme is proposed and compared to the existing methods; the integration error is reduced when using theoretical photoelastic parameters to calculate the stress component with the same points. Results show that when the value of Δx/Δy approaches one, the error is minimum, and although the interpolation error is inevitable, it has limited influence on the accuracy of the result. Finally, examples are presented for determining the stresses in a circular plate and ring subjected to diametric loading. Results show that the proposed approach provides a complete solution for determining the full-field stresses in photoelastic models.

[Parental Stress and psychopathological traits in children and adolescents. A controlled study].

PubMed

Gatta, Michela; Balottin, Laura; Mannarini, Stefania; Birocchi, Valentina; Del Col, Lara; Battistella, Pier Antonio

2016-01-01

Since parental stress and family empowerment were shown to influence children's and adolescents' outcome, especially in the case of psychotherapeutic treatments, the present study aims to deeply explore factors that are likely to impact on stress and empowerment in parents of children with a psychiatric diagnosis. Parenting stress and empowerment have been compared between 45 parents of children with a psychiatric disorder and 96 parents of children without psychiatric disorders. Parenting stress appeared to be higher in patients' parents and it varied according to disorder severity, while socio-demographic variables seemed to influence the stress levels only to a slight extent. Moreover parental stress and empowerment influenced each other within the parental couple. Developing interventions aimed to support parenting and to involve fathers in the parent-child relationship, focused on increasing parents empowerment and self-efficacy, could contribute to decrease stress and positively influence children's psychopathology.

The effect of implant number and position on the stress behavior of mandibular implant retained overdentures: A three-dimensional finite element analysis.

PubMed

Topkaya, Tolga; Solmaz, Murat Yavuz

2015-07-16

The present study evaluated the effects of ball anchor abutment attached to implants with a 4.30 mm diameter and 11 mm insert length on stress distribution in a patient without any remaining teeth in the lower jaw. In the study, the stress analysis was performed for five different configurations (2 with 4 implant-supported and 3 with 2 implant-supported) and three different loading types using ANSYS Workbench software. The stresses measured in the 4 implant-supported models were lower compared to the stresses measured in the 2 implant-supported models. The stresses on the implants intensified on the cervical region of the implants. When the effects of the loading sites on the stress were examined, the loading on the first molar tooth produced the highest stresses on the implants. Copyright © 2015 Elsevier Ltd. All rights reserved.

The role of peel stresses in cyclic debonding

NASA Technical Reports Server (NTRS)

Everett, R. A., Jr.

1982-01-01

When an adhesively bonded joint is undergoing cyclic loading, one of the possible damage modes that occurs is called cyclic debonding - progressive separation of the adherends by failure of the adhesive bond under cyclic loading. In most practical structures, both peel and shear stresses exist in the adhesive bonding during cyclic loading. The results of an experimental and analytical study to determine the role of peel stresses on cyclic debonding in a mixed mode specimen are presented. Experimentally, this was done by controlling the forces that create the peel stresses by applying a clamping force to oppose the peel stresses. Cracked lap shear joints were chosen for this study. A finite element analysis was developed to assess the effect of the clamping force on the strain energy release rates due to shear and peel stresses. The results imply that the peel stress is the principal stress causing cyclic debonding.

Restraint stress alters neutrophil and macrophage phenotypes during wound healing

PubMed Central

Tymen, Stéphanie D.; Rojas, Isolde G.; Zhou, Xiaofeng; Fang, Zong Juan; Zhao, Yan; Marucha, Phillip T.

2013-01-01

Previous studies reported that stress delays wound healing, impairs bacterial clearance, and elevates the risk for opportunistic infection. Neutrophils and macrophages are responsible for the removal of bacteria present at the wound site. The appropriate recruitment and functions of these cells are necessary for efficient bacterial clearance. In our current study we found that restraint stress induced an excessive recruitment of neutrophils extending the inflammatory phase of healing, and the gene expression of neutrophil attracting chemokines MIP-2 and KC. However, restraint stress did not affect macrophage infiltration. Stress decreased the phagocytic abilities of phagocytic cells ex vivo, yet it did not affect superoxide production. The cell surface expression of adhesion molecules CD11b and TLR4 were decreased in peripheral blood monocytes in stressed mice. The phenotype of macrophages present at the wound site was also altered. Gene expression of markers of pro-inflammatory classically activated macrophages, CXCL10 and CCL5, were down-regulated; as were markers associated with wound healing macrophages, CCL22, IGF-1, RELMα; and the regulatory macrophage marker, chemokine CCL1. Restraint stress also induced up-regulation of IL10 gene expression. In summary, our study has shown that restraint stress suppresses the phenotype shift of the macrophage population, as compared to the changes observed during normal wound healing, while the number of macrophages remains constant. We also observed a general suppression of chemokine gene expression. Modulation of the macrophage phenotype could provide a new therapeutic approach in the treatment of wounds under stress conditions in the clinical setting. PMID:22884902

Analysis of edge impact stresses in composite plates

NASA Technical Reports Server (NTRS)

Moon, F. C.; Kang, C. K.

1974-01-01

The in-plane edge impact of composite plates, with or without a protection strip, is investigated. A computational analysis based on the Fast Fourier Transform technique is presented. The particular application of the present method is in the understanding of the foreign object damage problem of composite fan blades. The method is completely general and may be applied to the study of other stress wave propagation problems in a half space. Results indicate that for the protective strip to be effective in reducing impact stresses in the composite the thickness must be equal or greater than the impact contact dimension. Large interface shear stresses at the strip - composite boundary can be induced under impact.

The Effectiveness of Group Training of CBT-Based Stress Management on Anxiety, Psychological Hardiness and General Self-Efficacy Among University Students.

PubMed

Molla Jafar, Hamdam; Salabifard, Seddigheh; Mousavi, Seyedeh Maryam; Sobhani, Zahra

2015-09-28

Admission to university is a very sensitive period of life for efficient, active, and young workforces in any country, and it is mostly associated with many changes in social and human relationships. These changes lead to anxiety in students. Moreover, humans need certain functions in order to adaptively deal with different life situations and challenges. By training stress management, these functions can help human acquire the required abilities. The present study was aimed at investigating the effectiveness of stress management training in anxiety, psychological hardiness, and general self-efficacy among university students. The study was a quasi-experimental intervention (pretest-posttest-follow-up) including a control group, it was a fundamental applied study. The statistical population consisted of all students of Islamic Azad University, Karaj, Iran. Convenient sampling was employed to select 30 students who were divided into an experimental group (n=15) and a control group (n=15). Before stress management training, both groups filled out Beck Anxiety Inventory, Long and Goulet scale of psychological hardiness, and General Self-efficacy Scale (GSE-10). Afterwards, the experimental group was provided with stress management training. And after the experiment, the abovementioned questionnaires and scales were responded by the two groups. Finally the collected data were analyzed and compared using one-way MANOVA. The results of MANOVA indicated that there was a significant difference between the two groups in terms of anxiety, hardiness, and general self-efficacy (p<0.001). According to the results of the present study and those of previous investigations that are in agreement with those of the present study, it can be concluded that stress management among university students cause anxiety to drop; moreover, it enhances their psychological hardiness and self-efficacy. In regard with the role and importance of stress management, training this skill should be included in educational plans of university.

The Effectiveness of Group Training of CBT-Based Stress Management on Anxiety, Psychological Hardiness and General Self-Efficacy among University Students

PubMed Central

Jafar, Hamdam Molla; Salabifard, Seddigheh; Mousavi, Seyedeh Maryam; Sobhani, Zahra

2016-01-01

Background: Admission to university is a very sensitive period of life for efficient, active, and young workforces in any country, and it is mostly associated with many changes in social and human relationships. These changes lead to anxiety in students. Moreover, humans need certain functions in order to adaptively deal with different life situations and challenges. By training stress management, these functions can help human acquire the required abilities. Objective: The present study was aimed at investigating the effectiveness of stress management training in anxiety, psychological hardiness, and general self-efficacy among university students. Method: The study was a quasi-experimental intervention (pretest-posttest-follow-up) including a control group, it was a fundamental applied study. The statistical population consisted of all students of Islamic Azad University, Karaj, Iran. Convenient sampling was employed to select 30 students who were divided into an experimental group (n=15) and a control group (n=15). Before stress management training, both groups filled out Beck Anxiety Inventory, Long and Goulet scale of psychological hardiness, and General Self-efficacy Scale (GSE-10). Afterwards, the experimental group was provided with stress management training. And after the experiment, the abovementioned questionnaires and scales were responded by the two groups. Finally the collected data were analyzed and compared using one-way MANOVA. Results: The results of MANOVA indicated that there was a significant difference between the two groups in terms of anxiety, hardiness, and general self-efficacy (p<0.001). Conclusion: According to the results of the present study and those of previous investigations that are in agreement with those of the present study, it can be concluded that stress management among university students cause anxiety to drop; moreover, it enhances their psychological hardiness and self-efficacy. In regard with the role and importance of stress management, training this skill should be included in educational plans of university. PMID:26755483

Correlation between stressors and academic performance in second year medical students.

PubMed

Nuallaong, Winitra

2011-12-01

The present study aimed to find which type of stressors correlating to academic performance in second year medical students. One-hundred and eighty three second year medical students of Thammasat University participated in a three-week cross-sectional study. The self-report questionnaire consisted of Thai stress test, stress factors and examination grades referring academic performance were applied in the present study. Females felt stress more than males in severe, high, and medium level of stress. There was no low level of stress and no correlation between stress level and the entrance programs. Academic performance found relating to 1) fear of doing a mistake, 2) feeling of competition or comparison, 3) unilateral headache, 4) worrying, and 5) poor concentration. Students with poor concentration had significantly decreasing grade in the second year (p < 0.01). Interestingly, worrying, feeling of competition or comparison, and fear of doing a mistake correlated to increasing grade in some terms (p < 0.05). Specifically to poor concentration, there were medium linear association with fatigue, poor memory, feeling confused, feeling sad, feeling angry or irritable, changing appetite, and headache from stress (p < 0.01). Poor concentration was the only stressor significantly correlated with poorer academic performance. Poor concentration also correlated with physical, cognitive, and financial problems. The recommendation is to keep watching those issues in order to early detect problem about academic performance.

Study of flow stress and spall strength of additively manufactured Ti-6-4 alloy

NASA Astrophysics Data System (ADS)

Cohen, Amitay; Paris, Vitaly; Yosef-Hai, Arnon; Gudinetsky, Eli; Tiferet, Eitan

2017-06-01

The use of additive manufacturing (AM) by Electron Beam Melting (EBM) or Selective Laser Melting (SLM) has extensively grown in the past few years. A major goal in AM is to manufacture materials with mechanical properties at least as good as traditionally manufactured materials. In this work we present results of planar impact tests and Split Hopkinson Pressure Bar tests (SHPB) on Ti-6-4 manufactured by EBM and SLM processes. Results of planar impact tests on SLM samples display slightly higher spall strength compared to EBM while the stress at Hugoniot elastic limit (HEL) is practically the same. Stress strain curves based on SHPB measurements at two different strain rates present similar plastic flow stresses for SLM and EBM processed Ti-6-4 alloy, while the flow stress is about 20% higher than reported for commercial reference material. The strain to failure of both materials shows considerable strain rate sensitivity. The results of post-mortem analysis of spall fracture will also be presented.

Superconductivity Devices: Commercial Use of Space

NASA Technical Reports Server (NTRS)

Haertling, Gene (Principal Investigator); Furman, Eugene; Li, Guang

1996-01-01

The work described in this report covers various aspects of the Rainbow solid-state actuator and sensor technologies. It is presented in five parts dealing with sensor applications, nonlinear properties, stress-optic and electrooptic properties, stacks and arrays, and publications. The Rainbow actuator technology is a relatively new materials development which had its inception in 1992. It involves a new processing technique for preparing pre-stressed, high lead containing piezoelectric and electrostrictive ceramic materials. Ceramics fabricated by this method produce bending-mode actuator devices which possess several times more displacement and load bearing capacity than present-day benders. Since they can also be used in sensor applications, Rainbows are part of the family of materials known as smart ceramics. During this period, PLZT Rainbow ceramics were characterized with respect to their piezoelectric properties for potential use in stress sensor applications. Studies of the nonlinear and stress-optic/electrooptic birefringent properties were also initiated during this period. Various means for increasing the utility of stress-enhanced Rainbow actuators are presently under investigation.

Perinatal Psychoneuroimmunology: Protocols for the Study of Prenatal Stress and Its Effects on Fetal and Postnatal Brain Development.

PubMed

Frasch, Martin G; Baier, Carlos J; Antonelli, Marta C; Metz, Gerlinde A S

2018-01-01

Prenatal stress (PS) impacts early behavioral, neuroimmune, and cognitive development. Pregnant rat models have been very valuable in examining the mechanisms of such fetal programming. A newer pregnant sheep model of maternal stress offers the unique advantages of chronic in utero monitoring and manipulation. This chapter presents the techniques used to model single and multigenerational stress exposures and their pleiotropic effects on the offspring.

The role of fungal symbiosis in the adaptation of plants to high stress environments

USGS Publications Warehouse

Rodriguez, Russell J.; Redman, Regina S.; Henson, Joan M.

2004-01-01

All plants studied in natural ecosystemsare symbiotic with fungi that either resideentirely (endophytes) or partially(mycorrhizae) within plants. Thesesymbioses appear to adapt to biotic andabiotic stresses and may be responsible forthe survival of both plant hosts and fungalsymbionts in high stress habitats. Here wedescribe the role of symbiotic fungi inplant stress tolerance and present astrategy based on adaptive symbiosis topotentially mitigate the impacts of globalchange on plant communities.

Parenting Stress, Alliance, Child Contact, and Adjustment of Imprisoned Mothers and Fathers

ERIC Educational Resources Information Center

Loper, Ann Booker; Carlson, L. Wrenn; Levitt, Lacey; Scheffel, Kathryn

2009-01-01

The present study contrasted the parenting stress and adjustment patterns of 100 mothers and 111 fathers incarcerated in one of 11 U.S. prisons. In comparison to inmate mothers, fathers had less contact with children, higher levels of parenting stress, and poorer alliance with caregivers. For inmate mothers, higher levels of contact with…

Experimental Investigation of the Shuttle Transportation System Composite Overwrapped Pressure Vessels for Stress Rupture Life

NASA Technical Reports Server (NTRS)

Greene, Nathanael; Saulsberry, Regor; Yoder, Tommy; Forsyth, Brad; Carillo, Marlene; Thesken, John

2006-01-01

A viewgraph presentation describing stress rupture testing on Composite Overwrapped Pressure Vessels (COPV) is shown. The topics include: 1) Purpose for Testing; 2) NASA WSTF COPV Test Program; 3) NASA WSTF Test Facilities; 4) COPV Impact Study; 5) Fluids Compatibility Testing; 6) Stress Rupture Testing; and 7) COPV Lifting.

Coaction of Stress and Serotonin Transporter Genotype in Predicting Aggression at the Transition to Adulthood

ERIC Educational Resources Information Center

Conway, Christopher C.; Keenan-Miller, Danielle; Hammen, Constance; Lind, Penelope A.; Najman, Jake M.; Brennan, Patricia A.

2012-01-01

Despite consistent evidence that serotonin functioning affects stress reactivity and vulnerability to aggression, research on serotonin gene-stress interactions (G x E) in the development of aggression remains limited. The present study investigated variation in the promoter region of the serotonin transporter gene (5-HTTLPR) as a moderator of the…

Mindfulness-Based Mind Fitness Training: A Case Study of a High-Stress Predeployment Military Cohort

ERIC Educational Resources Information Center

Stanley, Elizabeth A.; Schaldach, John M.; Kiyonaga, Anastasia; Jha, Amishi P.

2011-01-01

Current military deployments have resulted in many psychological and physical health issues and created interest in protective measures to mitigate effects of prolonged and repetitive stress. Mindfulness training has been successfully used for stress reduction in other contexts. The following case report presents a detachment of U.S. Marines who…

Expression of genes associated with stress conditions by Listeria monocytogenes in interaction with nisin producer Lactococcus lactis.

PubMed

Miranda, Rodrigo Otávio; Campos-Galvão, Maria Emilene Martino; Nero, Luís Augusto

2018-03-01

The use of nisin producers in foods is considered a mitigation strategy to control foodborne pathogens growth, such as Listeria monocytogenes, due to the production of this bacteriocin in situ. However, when the bacteriocin does not reach an adequate concentration, the target bacteria can develop a cross-response to different stress conditions in food, such as acid, thermal and osmotic. This study aimed to evaluate the interaction of a nisin-producing strain of Lactococcus lactis DY-13 and L. monocytogenes in BHI and skim milk, and its influence on general (sigB), acid (gadD2), thermal (groEL) and osmotic (gbu) stress-related genes of the pathogen. L. monocytogenes populations decreased approximately 2log in BHI and 1log in milk after 24h in co-culture with the nisin producer L. lactis, coherent with the increasing expression of nisK. Expression of stress-related genes by L. monocytogenes presented lower oscillation in BHI than in milk, indicating its better ability to survive in milk, despite the higher nisin production. Stress-related genes presented a varied expression by L. monocytogenes in the tested conditions: sigB expression remained stable or reduced over time; gadD2 presented high expression in milk; groEL presented low expression in BHI when compared to milk, trending to decrease overtime; gbu expression in milk after 24h was lower than in BHI. The presented study demonstrated the growth of a nisin producer L. lactis can affect the expression of stress-related genes by L. monocytogenes, and understating these mechanisms is crucial to enhance the conservation methods employed in foods. Copyright © 2017 Elsevier Ltd. All rights reserved.

A new setup for studying thermal microcracking through acoustic emission monitoring

NASA Astrophysics Data System (ADS)

Griffiths, Luke; Heap, Michael; Baud, Patrick; Schmittbuhl, Jean

2016-04-01

Thermal stressing is common in geothermal environments and has been shown in the laboratory to induce changes in the physical and mechanical properties of rocks. These changes are generally considered to be a consequence of the generation of thermal microcracks and debilitating chemical reactions. Thermal microcracks form as a result of the build-up of internal stresses due to: (1) the thermal expansion mismatch between the different phases present in the material, (2) thermal expansion anisotropy within individual minerals, and (3) thermal gradients. The generation of cracks during thermal stressing has been monitored in previous studies using the output of acoustic emissions (AE), a common proxy for microcrack damage, and through microstructural observations. Here we present a new experimental setup which is optimised to record AE from a rock sample at high temperatures and under a servo-controlled uniaxial stress. The design is such that the AE transducer is embedded in the top of the piston, which acts as a continuous wave guide to the sample. In this way, we simplify the ray path geometry whilst minimising the number of interfaces between the microcrack and the transducer, maximising the quality of the signal. This allows for an in-depth study of waveform attributes such as energy, amplitude, counts and duration. Furthermore, the capability of this device to apply a servo-controlled load on the sample, whilst measuring strain in real time, leads to a spectrum of possible tests combining mechanical and thermal stress. It is also an essential feature to eliminate the build-up of stresses through thermal expansion of the pistons and the sample. We plan a systematic experimental study of the AE of thermally stressed rock during heating and cooling cycles. We present results from pilot tests performed on Darley Dale sandstone and Westerly granite. Understanding the effects of thermal stressing in rock is of particular interest at a geothermal site, where circulating fluids influence the temperature field in the surrounding rock mass. These stresses can, for example, provoke thermal borehole breakouts due to cooling-induced tensile microcracking or may be actively used to enhance the injectivity of geothermal wells.

Stressful life events during adolescence and risk for externalizing and internalizing psychopathology: a meta-analysis.

PubMed

March-Llanes, Jaume; Marqués-Feixa, Laia; Mezquita, Laura; Fañanás, Lourdes; Moya-Higueras, Jorge

2017-12-01

The main objective of the present research was to analyze the relations between stressful life events and the externalizing and internalizing spectra of psychopathology using meta-analytical procedures. After removing the duplicates, a total of 373 papers were found in a literature search using several bibliographic databases, such as the PsycINFO, Medline, Scopus, and Web of Science. Twenty-seven studies were selected for the meta-analytical analysis after applying different inclusion and exclusion criteria in different phases. The statistical procedure was performed using a random/mixed-effects model based on the correlations found in the studies. Significant positive correlations were found in cross-sectional and longitudinal studies. A transactional effect was then found in the present study. Stressful life events could be a cause, but also a consequence, of psychopathological spectra. The level of controllability of the life events did not affect the results. Special attention should be given to the usage of stressful life events in gene-environment interaction and correlation studies, and also for clinical purposes.

Psychobiology of cumulative trauma: hair cortisol as a risk marker for stress exposure in women.

PubMed

Morris, Matthew C; Abelson, James L; Mielock, Alyssa S; Rao, Uma

2017-07-01

Childhood trauma (CT) is associated with long-lasting alterations of the hypothalamic-pituitary-adrenal (HPA) axis and elevated risk for stress exposure in adulthood. Although HPA alterations are present in the early aftermath of trauma, it remains unclear how initial HPA activity is associated with subsequent stress exposure and whether CT exposure influences the strength and direction of this association. The present study examined prospective associations between hair cortisol content (HCC) and stress exposure from baseline to 3-month follow-up in young adult women with recent (i.e. past 3 months) exposure to interpersonal violence (IPV; i.e. physical or sexual assault) and non-traumatized controls. History of significant CT abuse or neglect was determined based on clinical cutoffs for a self-report CT measure: 12 women had abuse or neglect and recent IPV exposure (CT + IPV); 7 women had abuse or neglect but no IPV exposure (CT); 15 women had no history of trauma (NTC). HCC was computed for 3 cm sections reflecting cortisol secretion during the 3 months preceding the baseline assessment. The interaction of cumulative trauma and HCC predicted stress exposure over 3-month follow-up, controlling for baseline stress exposure and depressive symptoms. Simple slopes analyses revealed that lower baseline HCC predicted greater stress exposure in the CT + IPV group compared to the CT group; HCC was not associated with stress exposure in the NTC group. The present findings highlight the potential utility of HCC as a predictor of stress exposure for women with a history of childhood abuse or neglect, particularly in the context of recent IPV. Lay summary Adults with a history of CT show long-lasting alterations in major stress response systems, including the HPA axis. They are also more likely to experience stressful life events in adulthood. However, it is not clear how altered HPA activity influences risk for stress exposure and whether CT affects their relationship. The results from this study show that lower HPA activity (measured with hair cortisol) predicted greater stress exposure in women with CT - particularly for women who also experienced recent incidents involving physical or sexual assault.

Evaluation of Oxidative Stress in Bipolar Disorder in terms of Total Oxidant Status, Total Antioxidant Status, and Oxidative Stress Index

PubMed Central

CİNGİ YİRÜN, Merve; ÜNAL, Kübranur; ALTUNSOY ŞEN, Neslihan; YİRÜN, Onur; AYDEMİR, Çiğdem; GÖKA, Erol

2016-01-01

Introduction Bipolar disorder is one of the most debilitating psychiatric disorders characterized by disruptive episodes of mania/hypomania and depression. Considering the complex role of biological and environmental factors in the etiology of affective disorders, recent studies have focused on oxidative stress, which may damage nerve cell components and take part in pathophysiology. The aim of the present study was to contribute to the data about oxidative stress in bipolar disorder by detecting the total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI) levels of manic episode (ME) and euthymic (EU) patients and by comparing these results with those of healthy controls (HCs). Methods The study population consisted of 28 EU outpatients meeting the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria for bipolar disorder I and 23 inpatients who were currently hospitalized in a psychiatry ward with the diagnosis of the bipolar disorder ME according to the DSM-5 criteria. Forty-three healthy subjects were included in the study as the control group (HC). Serum TAS, TOS, and OSI levels of all the participants were determined. Results Statistical analysis of serum TAS, TOS, and OSI levels did not show any significant differences between the ME patients, EU patients, and HCs. Comparison between the bipolar disorder patients (ME+EU) and HC also did not reveal any statistically significant difference between these two groups in terms of serum TAS, TOS, and OSI levels. Conclusion To date, studies on oxidative stress in bipolar disorder have led to controversial results. In the present study, no statistically significant difference was detected between the oxidative parameters of bipolar disorder patients and HCs. In order to comprehensively evaluate oxidative stress in bipolar disorder, further studies are needed. PMID:28373794

Evaluation of Oxidative Stress in Bipolar Disorder in terms of Total Oxidant Status, Total Antioxidant Status, and Oxidative Stress Index.

PubMed

Cingi Yirün, Merve; Ünal, Kübranur; Altunsoy Şen, Neslihan; Yirün, Onur; Aydemir, Çiğdem; Göka, Erol

2016-09-01

Bipolar disorder is one of the most debilitating psychiatric disorders characterized by disruptive episodes of mania/hypomania and depression. Considering the complex role of biological and environmental factors in the etiology of affective disorders, recent studies have focused on oxidative stress, which may damage nerve cell components and take part in pathophysiology. The aim of the present study was to contribute to the data about oxidative stress in bipolar disorder by detecting the total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI) levels of manic episode (ME) and euthymic (EU) patients and by comparing these results with those of healthy controls (HCs). The study population consisted of 28 EU outpatients meeting the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria for bipolar disorder I and 23 inpatients who were currently hospitalized in a psychiatry ward with the diagnosis of the bipolar disorder ME according to the DSM-5 criteria. Forty-three healthy subjects were included in the study as the control group (HC). Serum TAS, TOS, and OSI levels of all the participants were determined. Statistical analysis of serum TAS, TOS, and OSI levels did not show any significant differences between the ME patients, EU patients, and HCs. Comparison between the bipolar disorder patients (ME+EU) and HC also did not reveal any statistically significant difference between these two groups in terms of serum TAS, TOS, and OSI levels. To date, studies on oxidative stress in bipolar disorder have led to controversial results. In the present study, no statistically significant difference was detected between the oxidative parameters of bipolar disorder patients and HCs. In order to comprehensively evaluate oxidative stress in bipolar disorder, further studies are needed.

Arbuscular mycorrhiza effects on plant performance under osmotic stress.

PubMed

Santander, Christian; Aroca, Ricardo; Ruiz-Lozano, Juan Manuel; Olave, Jorge; Cartes, Paula; Borie, Fernando; Cornejo, Pablo

2017-10-01

At present, drought and soil salinity are among the most severe environmental stresses that affect the growth of plants through marked reduction of water uptake which lowers water potential, leading to osmotic stress. In general, osmotic stress causes a series of morphological, physiological, biochemical, and molecular changes that affect plant performance. Several studies have found that diverse types of soil microorganisms improve plant growth, especially when plants are under stressful conditions. Most important are the arbuscular mycorrhizal fungi (AMF) which form arbuscular mycorrhizas (AM) with approximately 80% of plant species and are present in almost all terrestrial ecosystems. Beyond the well-known role of AM in improving plant nutrient uptake, the contributions of AM to plants coping with osmotic stress merit analysis. With this review, we describe the principal direct and indirect mechanisms by which AM modify plant responses to osmotic stress, highlighting the role of AM in photosynthetic activity, water use efficiency, osmoprotectant production, antioxidant activities, and gene expression. We also discuss the potential for using AMF to improve plant performance under osmotic stress conditions and the lines of research needed to optimize AM use in plant production.

Self-Care for Nurse Leaders in Acute Care Environment Reduces Perceived Stress: A Mixed-Methods Pilot Study Merits Further Investigation.

PubMed

Dyess, Susan Mac Leod; Prestia, Angela S; Marquit, Doren-Elyse; Newman, David

2018-03-01

Acute care practice settings are stressful. Nurse leaders face stressful demands of numerous competing priorities. Some nurse leaders experience unmanageable stress, but success requires self-care. This article presents a repeated measures intervention design study using mixed methods to investigate a self-care simple meditation practice for nurse leaders. Themes and subthemes emerged in association with the three data collection points: at baseline (pretest), after 6 weeks, and after 12 weeks (posttest) from introduction of the self-care simple meditation practice. An analysis of variance yielded a statistically significant drop in perceived stress at 6 weeks and again at 12 weeks. Conducting future research is merited.

TRB3 reverses chemotherapy resistance and mediates crosstalk between endoplasmic reticulum stress and AKT signaling pathways in MHCC97H human hepatocellular carcinoma cells.

PubMed

Li, Yang; Zhu, Danxi; Hou, Lidan; Hu, Bin; Xu, Min; Meng, Xiangjun

2018-01-01

Tribbles homolog 3 (TRB3), a type of pseudokinase that contains a consensus serine/threonine kinase catalytic core structure, is upregulated in hepatocellular carcinoma. However, the effect of TRB3 expression in hepatocellular carcinoma and the molecular mechanisms underlying TRB3-mediated effects on tumorigenesis in hepatocellular carcinoma have not been fully elucidated. The present study focused on the effect of TRB3 expression in MHCC97H hepatocellular carcinoma cells and investigated the underlying molecular mechanisms in MHCC97H cells. In the present study, it was revealed that TRB3 was significantly overexpressed in the MHCC97H hepatocellular carcinoma cell compared with L-02 normal hepatic cells. Under endoplasmic reticulum (ER) stress induced by thapsigargin and tunicamycin, the levels of TRB3, CCAAT/enhancer binding protein homologous protein (CHOP), protein kinase B (AKT) and phosphorylated (p)AKT expression were upregulated. Furthermore, when the expression of TRB3 was silenced by short hairpin (sh)RNA, the survival of MHCC97H hepatocellular carcinoma cells was increased. Notably, following transduction with lentiviral containing TRB3-shRNA, cell survival also increased after treatment with chemotherapy drug cisplatin. The present study demonstrated that knockdown of CHOP by shRNA was able to reduce TRB3 expression, and the knockdown of TRB3 markedly increased the level of pAKT. TRB3 was overexpressed in MHCC97H hepatocellular carcinoma cells, particularly under endoplasmic reticulum stress. Knockdown of TRB3 was able to increase cell survival. Therefore, TRB3 expression may induce apoptosis and reverse resistance to chemotherapy in MHCC97H hepatic carcinoma cells. The present study suggests that TRB3 is a key molecule that mediates the crosstalk between ER stress and AKT signal pathways. Furthermore, the present study may provide further insight into the cancer biology of hepatocellular carcinoma and the development of anticancer drugs targeting the ER stress and AKT signaling pathways.

An Exploration of the Relationship between Depressive Symptoms and Cortisol Rhythms in Colorado Ranchers

ERIC Educational Resources Information Center

Schulze, Emily; Laudenslager, Mark; Coussons-Read, Mary

2009-01-01

Context: Although the effects of stress on health have been studied in numerous urban-dwelling populations, fewer studies have addressed these effects in rural populations, such as farmers and ranchers. Purpose: The present study focuses on seasonal levels of depressed affect and perceived stress in Western Colorado ranchers, and how those…

Perceived Stress and Coping Strategies among Newly Nurse Students in Clinical Practice

ERIC Educational Resources Information Center

Mahfouz, Rasha; Alsahli, Haya

2016-01-01

The present study aimed at assessing the stress level and coping strategies among students who were newly in Practicing the clinical training in different hospitals, at the Nursing College, Princess Nourah University. The study design was a descriptive analytical one. The study was conducted at the beginning of second semester in the academic year…

Multidimensional Profiling of Task Stress States for Human Factors: A Brief Review.

PubMed

Matthews, Gerald

2016-09-01

This article advocates multidimensional assessment of task stress in human factors and reviews the use of the Dundee Stress State Questionnaire (DSSQ) for evaluation of systems and operators. Contemporary stress research has progressed from an exclusive focus on environmental stressors to transactional perspectives on the stress process. Performance impacts of stress reflect the operator's dynamic attempts to understand and cope with task demands. Multidimensional stress assessments are necessary to gauge the different forms of system-operator interaction. This review discusses the theoretical and practical use of the DSSQ in evaluating multidimensional patterns of stress response. It presents psychometric evidence for the multidimensional perspective and illustrative profiles of subjective state response to task stressors and environments. Evidence is also presented on stress state correlations with related variables, including personality, stress process measures, psychophysiological response, and objective task performance. Evidence supports the validity of the DSSQ as a task stress measure. Studies of various simulated environments show that different tasks elicit different profiles of stress state response. Operator characteristics such as resilience predict individual differences in state response to stressors. Structural equation modeling may be used to understand performance impacts of stress states. Multidimensional assessment affords insight into the stress process in a variety of human factors contexts. Integrating subjective and psychophysiological assessment is a priority for future research. Stress state measurement contributes to evaluating system design, countermeasures to stress and fatigue, and performance vulnerabilities. It may also support personnel selection and diagnostic monitoring of operators. © 2016, Human Factors and Ergonomics Society.

Effects of acute and chronic psychological stress on platelet aggregation in mice.

PubMed

Matsuhisa, Fumikazu; Kitamura, Nobuo; Satoh, Eiki

2014-03-01

Although psychological stress has long been known to alter cardiovascular function, there have been few studies on the effect of psychological stress on platelets, which play a pivotal role in cardiovascular disease. In the present study, we investigated the effects of acute and chronic psychological stress on the aggregation of platelets and platelet cytosolic free calcium concentration ([Ca(2+)]i). Mice were subjected to both transportation stress (exposure to novel environment, psychological stress) and restraint stress (psychological stress) for 2 h (acute stress) or 3 weeks (2 h/day) (chronic stress). In addition, adrenalectomized mice were subjected to similar chronic stress (both transportation and restraint stress for 3 weeks). The aggregation of platelets from mice and [Ca(2+)]i was determined by light transmission assay and fura-2 fluorescence assay, respectively. Although acute stress had no effect on agonist-induced platelet aggregation, chronic stress enhanced the ability of the platelet agonists thrombin and ADP to stimulate platelet aggregation. However, chronic stress failed to enhance agonist-induced increase in [Ca(2+)]i. Adrenalectomy blocked chronic stress-induced enhancement of platelet aggregation. These results suggest that chronic, but not acute, psychological stress enhances agonist-stimulated platelet aggregation independently of [Ca(2+)]i increase, and the enhancement may be mediated by stress hormones secreted from the adrenal glands.

Residual stresses in passenger car wheels

DOT National Transportation Integrated Search

2006-11-05

The purpose of this paper is to present the extension of previous studies aimed at understanding the residual stress distribution in as-manufactured railroad wheels. In order to address loading conditions which are not axially symmetric, a manufactur...

Nocturnal time monitoring behavior ("clock-watching") in patients presenting to a sleep medical center with insomnia and posttraumatic stress symptoms.

PubMed

Krakow, Barry; Krakow, Jacoby; Ulibarri, Victor A; Krakow, Jessica

2012-09-01

Time monitoring behavior (TMB) commonly occurs among insomnia patients, often leads to frustration about sleeplessness, and perpetuates insomnia symptoms. Few studies have explored relationships between time monitoring and insomnia, and none have studied the potential relationships between insomnia, TMB, and posttraumatic stress symptoms (PSSs). In this retrospective chart review of 1078 patients seeking care at a sleep medical center, the patients presented with one of three chief sleep complaints (poor sleep quality, 51%; sleep-disordered breathing, 26%; and insomnia, 24%), and 32% reported moderate to severe PSSs. Both insomnia and time monitoring severity were greater in the 350 patients with PSSs compared with the 728 patients with minimal or no such symptoms. Insomnia and time monitoring severity correlated significantly with total posttraumatic stress scores and most strongly with the arousal subscale. Research on interventions to treat TMB may inform relationships between insomnia and posttraumatic stress.

[Multifactor Organizational Stress Risk Questionnaire--MOSRQ: a preliminary study of dimensions and structure].

PubMed

Zuffo, Riccardo Giorgio; Ferretti, Maria Santa

2012-01-01

INTRODUCTION. The aim of the present study is to demonstrate the validity of the MOSRQ, a questionnaire for the assessment of work related stress risk. This questionnaire has 38 items: 19 related to organizational stressors and 19 to strains. Firstly, it was performed a critical analysis of instruments reported in scientific literature; then relevant items about sources and consequences of work related stress were selected in order to obtain the questionnaire. Finally MOSRQ was administered to a sample of 2314 subjects mainly employed in private firms belonging to industry and service sectors. MOSRQ obtains a good index of reliability (alpha = .89 for organizational stressor/antecedents and alpha = .92 for strain/outcome). Factor analysis presents a structure with 3 factors both for the antecedents and for the outcomes of work related stress. In conclusion, it is claimed that MOSRQ has the necessary psychometric characteristics for use in research as well as in organizational contexts.

The Effect of Auriculotherapy on the Stress and the Outcomes of Assistant Reproductive Technologies in Infertile Women.

PubMed

Saffari, Mozhgan; Khashavi, Zahra; Valiani, Mahboubeh

2018-01-01

Infertility means failure to achieve pregnancy after one year of regular unprotected sexual intercourse. Infertile women may experience severe stress and depression. Numerous studies have indicated that auriculotherapy could reduce stress. Thus, the aim of the present study was to determine the effect of auriculotherapy on the stress and the outcome assisted reproductive technology in infertile women. The present study was a clinical trial that was conducted on 56 infertile women aged 20-45, who were assigned into two groups of intervention and control, from November 2014 to November 2015. The control group only received the routine treatments, while the intervention group, in addition to their routine treatment, received auriculotherapy for 8-10 sessions during menstrual cycle. Both groups completed Newton's Fertility Problem Inventory in three stages. The datasets collected for the study were analyzed using independent t -test, repeated-measures analysis of variance, and Chi-square test. The mean score of stress in the intervention group decreased significantly, compared to the control group prior to the embryo transfer and pregnancy test stages. Although insignificant, the rate of pregnancy in the intervention group was higher than the control group. There was a significant increase in the rate of clinical pregnancy in the intervention group, compared to the control. The results indicated that auriculotherapy might be effective in reducing stress and improving the outcome of assisted reproductive treatment.

Occupational imbalance and the role of perceived stress in predicting stress-related disorders.

PubMed

Håkansson, Carita; Ahlborg, Gunnar

2017-03-02

Stress-related disorders are the main reason for sick leave in many European countries. The aim of the present study was to explore whether perceived occupational imbalance predicts stress-related disorders, potential gender differences, and to explore the mediating role of perceived stress. Longitudinal data on 2223 employees in a public organization in Sweden were collected by surveys, and analyzed by logistic regression. Occupational imbalance predicted stress-related disorders among both women and men. However, what aspects of occupational imbalance which predicted stress-related disorders differ by gender. Perceived stress was not a mediator in these associations. How women and men perceived their occupational balance affected the risk of stress-related disorders. The results may be used to develop effective strategies to decrease stress-related disorders.

Immediate recall influences the effects of pre-encoding stress on emotional episodic long-term memory consolidation in healthy young men.

PubMed

Wolf, Oliver T

2012-05-01

The stress-associated activation of the hypothalamus-pituitary-adrenal axis influences memory. Several studies have supported the notion that post-learning stress enhances memory consolidation, while pre-retrieval stress impairs retrieval. Findings regarding the effects of pre-encoding stress, in contrast, have been rather inconsistent. In the current two studies, the impact of an immediate retrieval task on these effects was explored. In the first study, 24 healthy young male participants were exposed to a psychosocial laboratory stressor (Trier Social Stress Test) or a control condition before viewing positive, negative, and neutral photographs, which were accompanied by a brief narrative. Immediate as well as delayed (24 h later) free recall was assessed. Stress was expected to enhance emotional long-term memory without affecting immediate recall performance. Stress caused a significant increase in salivary cortisol concentrations but had no significant effects on immediate or delayed retrieval performance, even though a trend toward poorer memory of the stress group was apparent. Based on these findings, the second experiment tested the hypothesis that the beneficial effects of stress on emotional long-term memory performance might be abolished by an immediate recall test. In the second study (n = 32), the same design was used, except for the omission of the immediate retrieval test. This time stressed participants recalled significantly more negative photographs compared to the control group. The present study indicates that an immediate retrieval attempt of material studied after stress exposure can prevent or even reverse the beneficial effects of pre-encoding stress on emotional long-term memory consolidation.

Italian Present-day Stress Indicators: IPSI Database

NASA Astrophysics Data System (ADS)

Mariucci, M. T.; Montone, P.

2017-12-01

In Italy, since the 90s of the last century, researches concerning the contemporary stress field have been developing at Istituto Nazionale di Geofisica e Vulcanologia (INGV) with local and regional scale studies. Throughout the years many data have been analysed and collected: now they are organized and available for an easy end-use online. IPSI (Italian Present-day Stress Indicators) database, is the first geo-referenced repository of information on the crustal present-day stress field maintained at INGV through a web application database and website development by Gabriele Tarabusi. Data consist of horizontal stress orientations analysed and compiled in a standardized format and quality-ranked for reliability and comparability on a global scale with other database. Our first database release includes 855 data records updated to December 2015. Here we present an updated version that will be released in 2018, after new earthquake data entry up to December 2017. The IPSI web site (http://ipsi.rm.ingv.it/) allows accessing data on a standard map viewer and choose which data (category and/or quality) to plot easily. The main information of each single element (type, quality, orientation) can be viewed simply going over the related symbol, all the information appear by clicking the element. At the same time, simple basic information on the different data type, tectonic regime assignment, quality ranking method are available with pop-up windows. Data records can be downloaded in some common formats, moreover it is possible to download a file directly usable with SHINE, a web based application to interpolate stress orientations (http://shine.rm.ingv.it). IPSI is mainly conceived for those interested in studying the characters of Italian peninsula and surroundings although Italian data are part of the World Stress Map (http://www.world-stress-map.org/) as evidenced by many links that redirect to this database for more details on standard practices in this field.

Workplace spirituality as a moderator in relation between stress and health: An exploratory empirical assessment.

PubMed

Kumar, Vineet; Kumar, Sandeep

2014-06-01

The present study explores the role of workplace spirituality in moderating the relationship between occupational stress and the health of managerial personnel in India. A sample of 150 managers working in different public and private organizations was used to measure workplace spirituality, occupational stress, and health using the Spirituality at Work scale, the Occupational Stress Index and the 28-item General Health Questionnaire, respectively. The findings reveal that workplace spirituality moderates the negative relationship of stress and health. The study also found that stress has a negative impact on health while workplace spirituality positively correlated with health. The findings also support the practical importance of spirituality in the workplace for improving health conditions by providing a healthy atmosphere and meaningful work for employees. This exploratory study encourages future research to understand the role of spirituality in the workplace.

Stress-induced release of GUT peptides in young women classified as restrained or unrestrained eaters.

PubMed

Hilterscheid, Esther; Laessle, Reinhold

2015-12-01

Basal release of GUT peptides has been found to be altered in restrained eaters. Stress-induced secretion, however, has not yet been described, but could be a biological basis of overeating that exposes restrained eaters to a higher risk of becoming obese. The aim of the present study was to compare restrained and unrestrained eaters with respect to stress-induced release of the GUT peptides ghrelin and PYY. 46 young women were studied. Blood sampling for peptides was done before and after the Trier Social Stress Test. Ghrelin secretion after stress was significantly elevated in the restrained eaters, whereas no significant differences were detected for PYY. Stress-induced release of GUT peptides can be interpreted as a cause as well as a consequence of restrained eating.

Numerical and Experimental Study on the Residual Stresses in the Nitrided Steel

NASA Astrophysics Data System (ADS)

Song, X.; Zhang, Zhi-Qian; Narayanaswamy, S.; Huang, Y. Z.; Zarinejad, M.

2016-09-01

In the present work, residual stresses distribution in the gas nitrided AISI 4140 sample has been studied using finite element (FE) simulation. The nitrogen concentration profile is obtained from the diffusion-controlled compound layer growth model, and nitrogen concentration controls the material volume change through phase transformation and lattice interstitials which results in residual stresses. Such model is validated through residual stress measurement technique—micro-ring-core method, which is applied to the nitriding process to obtain the residual stresses profiles in both the compound and diffusion layer. The numerical and experimental results are in good agreement with each other; they both indicate significant stress variation in the compound layer, which was not captured in previous research works due to the resolution limit of the traditional methods.

Love-type wave propagation in a pre-stressed viscoelastic medium influenced by smooth moving punch

NASA Astrophysics Data System (ADS)

Singh, A. K.; Parween, Z.; Chatterjee, M.; Chattopadhyay, A.

2015-04-01

In the present paper, a mathematical model studying the effect of smooth moving semi-infinite punch on the propagation of Love-type wave in an initially stressed viscoelastic strip is developed. The dynamic stress concentration due to the punch for the force of a constant intensity has been obtained in the closed form. Method based on Weiner-hopf technique which is indicated by Matczynski has been employed. The study manifests the significant effect of various affecting parameters viz. speed of moving punch associated with Love-type wave speed, horizontal compressive/tensile initial stress, vertical compressive/tensile initial stress, frequency parameter, and viscoelastic parameter on dynamic stress concentration due to semi-infinite punch. Moreover, some important peculiarities have been traced out and depicted by means of graphs.

Adaptation to daily stress among mothers of children with an autism spectrum disorder: the role of daily positive affect.

PubMed

Ekas, Naomi V; Whitman, Thomas L

2011-09-01

Raising a child with an autism spectrum disorder is a challenging experience that can impact maternal well-being. Using a daily diary methodology, this study investigates (1) the relationship between stress and negative affect, and (2) the role of daily positive affect as a protective factor in the stress and negative affect relationship. Results from hierarchical linear models revealed that higher levels of stress were associated with decreased negative affect, both within and across days. Daily positive affect buffered the immediate and longer-lasting negative impact of stress on days of low to moderate levels of stress. Implications of the present study are discussed with regard to theoretical models of positive affect, the development of intervention programs, and directions for future research.

Effect of acute psychological stress on response inhibition: An event-related potential study.

PubMed

Qi, Mingming; Gao, Heming; Liu, Guangyuan

2017-04-14

This study aimed to investigate the effect of acute psychological stress on response inhibition and its electrophysiological correlates using a dual-task paradigm. Acute stress was induced by a primary task (mental arithmetic task), which consisted of a stress block and a control block. Response inhibition was measured using a secondary task (Go/NoGo task). In each trial, a Go/NoGo stimulus was presented immediately after the mental arithmetic task. The results revealed increased subjective stress and negative affect for the stress relative to control block, suggesting that the mental arithmetic task triggered a reliable stress response. ERPs locked to the Go/NoGo stimuli revealed that decreased P2 and increased N2 components were evoked for the stress block compared to the control block. These results demonstrated that acute psychological stress alters the response inhibition process by reducing the early selective attention process and enhancing the cognitive control process. Copyright © 2017 Elsevier B.V. All rights reserved.

Chronic stress, catecholamines, and sleep disturbance at Three Mile Island

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

Davidson, L.M.; Fleming, R.; Baum, A.

The present study was concerned with the relationship between chronic stress and sleep disturbance. Previous research has provided evidence of chronic stress responding among people living near the Three Mile Island nuclear generating facility. Compared to control subjects, the TMI group has exhibited greater symptom reporting, poorer performance on behavioral measures of concentration, and elevated levels of urinary norepinephrine and epinephrine. Other research has suggested a relationship between arousal and insomnia. The extent to which stress and sleep disturbances were experienced by residents at TMI was examined and compared to levels of stress and sleep disturbance among a group ofmore » control subjects. The relationship between stress and sleep disturbances was also examined. Results indicated that TMI area residents exhibited more stress than the controls and reported greater disturbance of sleep. Modest relationships among stress and sleep measures suggested that the symptoms of stress measured in this study were not primary determinants of sleep problems.« less

Oxytocin and Stress-related Disorders: Neurobiological Mechanisms and Treatment Opportunities

PubMed Central

Sippel, Lauren M.; Allington, Casey E.; Pietrzak, Robert H.; Harpaz-Rotem, Ilan; Mayes, Linda C.; Olff, Miranda

2017-01-01

Novel pharmacotherapies that improve outcomes for individuals with stress-related psychiatric disorders are needed. The neurohormone oxytocin (OT) is a promising candidate given its influence on the social–emotional brain. In this review, we present an overview of evidence supporting OT’s utility for treating major depressive disorder and posttraumatic stress disorder. We first discuss endogenous OT, which research suggests is not yet a reliable biomarker of stress-related disorders. Second, we review effects of intranasal (IN) OT on processes relevant to stress-related disorders in healthy populations (anhedonia, reward processing, psychosocial stress reactivity, fear/anxiety, and social behavior) and their neurobiological mechanisms (e.g., the salience network and hypothalamic–pituitary–adrenal axis). Third, we present the sparse but promising findings from clinical populations, followed by discussion of critical moderating variables to consider in the service of maximizing the therapeutic potential of OT (e.g., patient sex and child maltreatment). We also identify heterogeneous findings and limitations of existing research, including reliance on single-dose studies in psychiatrically healthy samples and unanswered questions regarding the effectiveness of IN drug delivery and dosing schedules. Well-controlled multidose studies including women and measures of potentially moderating variables are sorely needed and would inform our understanding of the utility of OT for preventing and treating stress-related psychiatric disorders. PMID:28649672

Parents' stressful life events and adolescent depressed mood.

PubMed

Ge, X; Conger, R D; Lorenz, F O; Simons, R L

1994-03-01

The present study of 451 families living in the rural Midwest examines a mediational model of the relationship between the stressful life events experienced by parents and adolescent depressed mood. This model is intended to overcome two limitations in previous research on the relationship between parents' stressful events and adolescent depressed mood by 1) examining a mediating process involving parental mood and parenting behavior, and 2) using multiple informants to assess the theoretical constructs. Findings from the present study indicate that stressful life events experienced by parents are first related to parents' depressed mood which operates to disrupt skillful parenting practices. The disrupted parenting practices in turn place adolescents at increased risk for developing depressive symptoms. The results show that inclusion of these mediating processes represents a significant improvement over the bivariate model and that the hypothesized mediational model generalizes to four parent-adolescent dyads: fathers and sons, fathers and daughters, mothers and sons, and mothers and daughters. Moreover, parents' stressful life events are related directly to adolescent boys' depressed mood only when parents' reports are included in both theoretical constructs. When parents' reports are removed as an indicator for the adolescent depressed mood construct, the effects of parental stress on adolescent depressed mood are largely accounted for by stress-related parental depressed mood and harsh/inconsistent parenting.

Design of the study: how can health care help female breast cancer patients reduce their stress symptoms? A randomized intervention study with stepped-care.

PubMed

Nordin, Karin; Rissanen, Ritva; Ahlgren, Johan; Burell, Gunilla; Fjällskog, Marie-Louise; Börjesson, Susanne; Arving, Cecilia

2012-05-04

A life threatening illness such as breast cancer can lead to a secondary diagnosis of PTSD (post traumatic stress disorder) with intrusive thoughts and avoidance as major symptoms. In a former study by the research group, 80% of the patients with breast cancer reported a high level of stress symptoms close to the diagnosis, such as intrusive thoughts and avoidance behavior. These symptoms remained high throughout the study. The present paper presents the design of a randomized study evaluating the effectiveness and cost-effectiveness of a stress management intervention using a stepped-care design. Female patients over the age of 18, with a recent diagnosis of breast cancer and scheduled for adjuvant treatment in the form of chemotherapy, radiation therapy and/or hormonal therapy are eligible and will consecutively be included in the study. The study is a prospective longitudinal intervention study with a stepped-care approach, where patients will be randomised to one of two interventions in the final stage of treatment. The first step is a low intensity stress-management intervention that is given to all patients. Patients who do not respond to this level are thereafter given more intensive treatment at later steps in the program and will be randomized to more intensive stress-management intervention in a group setting or individually. The primary out-come is subjective distress (intrusion and avoidance) assessed by the Impact of Event Scale (IES). According to the power-analyses, 300 patients are planned to be included in the study and will be followed for one year. Other outcomes are anxiety, depression, quality of life, fatigue, stress in daily living and utilization of hospital services. This will be assessed with well-known psychometric tested questionnaires. Also, the cost-effectiveness of the intervention given in group or individually will be evaluated. This randomized clinical trial will provide additional empirical evidence regarding the effectiveness of a stress-management program given in group or individually during adjuvant therapy in terms of decreased stress, minimizing fatigue, and maintaining or enhancing patients' quality of life and psychological well-being. ClinicalTrials.gov Identifier: NCT01555645.

Impacts of obesity and stress on neuromuscular fatigue development and associated heart rate variability.

PubMed

Mehta, R K

2015-02-01

Obesity and stress are independently associated with decrements in neuromuscular functions. The present study examined the interplay of obesity and stress on neuromuscular fatigue and associated heart rate variability (HRV). Forty-eight non-obese (18.5

Effect of khat, its constituents and restraint stress on free radical metabolism of rats.

PubMed

Al-Qirim, Tariq M; Shahwan, Moyad; Zaidi, Kashif R; Uddin, Qamar; Banu, Naheed

2002-12-01

The leaves of khat (Catha edulis) are found to have stimulating and pleasurable effect and are chewed habitually by people of East Africa and Arabian Peninsula. Due to various toxic and psychostimulative effect of khat the present study was undertaken to evaluate the effect of intragastric khat alone or its major constituents flavonoids/alkaloids administration and before and after 4 h of immobilization stress in terms of alteration of free radical scavenging/metabolizing enzymes, uric acid and glucose in rats. Oral khat, alkaloid administration or 4 h restraint stress resulted in the decrease of the circulating levels of superoxide dismutase, catalase, glutathione-S-transferase and glucose with enhanced uric acid concentrations as compared with control rats. Oral treatment with flavonoid fraction of khat was found to enhance the activities of GST and catalase but showed no effect on SOD while the level of glucose was decreased and uric acid increased. The levels of these biochemical parameters were more altered in post stress khat/alkaloid treated rats than pre stress khat/alkaloid treated rats. The alteration in the levels of SOD, GST, catalase and uric acid in the pre stress khat treated rats were comparable with that of khat alone, except the level of glucose which was further decreased in pre stress khat treated rats. The flavonoid fraction of khat reduced the stress induced oxidative stress in terms of above mentioned biochemical parameters. The present study suggests that khat alone or khat/alkaloid consumption preceding stress may significantly decrease the levels of free radical metabolizing/scavenging enzymes and glucose leading to enhanced free radical concentration and toxicity of khat, which could be due to its alkaloid fraction as flavonoids were found to show antioxidant properties for oxidative stress generated during restraint stress.

Dynamic properties and damping predictions for laminated plates: High order theories - Timoshenko beam

NASA Astrophysics Data System (ADS)

Diveyev, Bohdan; Konyk, Solomija; Crocker, Malcolm J.

2018-01-01

The main aim of this study is to predict the elastic and damping properties of composite laminated plates. This problem has an exact elasticity solution for simple uniform bending and transverse loading conditions. This paper presents a new stress analysis method for the accurate determination of the detailed stress distributions in laminated plates subjected to cylindrical bending. Some approximate methods for the stress state predictions for laminated plates are presented here. The present method is adaptive and does not rely on strong assumptions about the model of the plate. The theoretical model described here incorporates deformations of each sheet of the lamina, which account for the effects of transverse shear deformation, transverse normal strain-stress and nonlinear variation of displacements with respect to the thickness coordinate. Predictions of the dynamic and damping values of laminated plates for various geometrical, mechanical and fastening properties are presented. Comparison with the Timoshenko beam theory is systematically made for analytical and approximation variants.

Seawater inhalation induces acute lung injury via ROS generation and the endoplasmic reticulum stress pathway

PubMed Central

Li, Cong-Cong; Lu, Xi; Qian, Wei-Sheng; Li, Yu-Juan; Jin, Fa-Guang; Mu, De-Guang

2018-01-01

Seawater (SW) inhalation can induce acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). In the present study, SW induced apoptosis of rat alveolar epithelial cells and histopathological alterations to lung tissue. Furthermore, SW administration increased generation of reactive oxygen species (ROS), whereas pretreatment with the ROS scavenger, N-acetyl-L-cysteine (NAC), significantly decreased ROS generation, apoptosis and histopathological alterations. In addition, SW exposure upregulated the expression levels of glucose-regulated protein 78 (GRP78) and CCAAT/enhancer binding protein homologous protein (CHOP), which are critical proteins in the endoplasmic reticulum (ER) stress response, thus indicating that SW may activate ER stress. Conversely, blocking ER stress with 4-phenylbutyric acid (4-PBA) significantly improved SW-induced apoptosis and histopathological alterations, whereas an ER stress inducer, thapsigargin, had the opposite effect. Furthermore, blocking ROS with NAC inhibited SW-induced ER stress, as evidenced by the downregulation of GRP78, phosphorylated (p)-protein kinase R-like ER kinase (PERK), p-inositol-requiring kinase 1α (IRE1α), p-50 activating transcription factor 6α and CHOP. In addition, blocking ER stress with 4-PBA decreased ROS generation. In conclusion, the present study indicated that ROS and ER stress pathways, which are involved in alveolar epithelial cell apoptosis, are important in the pathogenesis of SW-induced ALI. PMID:29436612

Relationship between oxidative stress and "burning mouth syndrome" in female patients: a scientific hypothesis.

PubMed

Tatullo, M; Marrelli, M; Scacco, S; Lorusso, M; Doria, S; Sabatini, R; Auteri, P; Cagiano, R; Inchingolo, F

2012-09-01

Burning Mouth Syndrome (BMS) is characterized by burning sensation and pain in the mouth with or without inflammatory signs and specific lesions. Aim of the present study was to investigate about a possible correlation between the Burning Mouth Syndrome and oxidative stress. We recruited 18 healthy female patients between 54 and 68 years of age with a diagnosis of Burning Mouth Syndrome. Oxidative stress assessment was performed by means of an integrated analytical system composed of a photometer and a mini-centrifuge (FRAS4, H and D s.r.l., Parma, Italy). Samples of whole capillary blood were taken by a finger puncture in a heparinized tube and immediately centrifuged; a small amount of samples plasma (10 microL) were thereafter tested for total oxidant capacity (d-ROMs test) and biological antioxidant potential as iron-reducing activity (BAP test) (Diacron International s.r.l., Grosseto, Italy). Our results indicate that female patients affected by Burning Mouth Syndrome show significantly different d-ROMs and BAP levels, similar to those present in oxidative stress condition with respect to the general population. It was also emphasized that, after the most painful phase, the levels representing the present oxidative stress, progressively return to normal, even if still significantly higher 7 days after, with respect to the normal population. No similar study was performed up to now. This study confirms the effectiveness of antioxidant treatments in the patients affected by BMS, in order to prevent or decrease the onset of oxidative stress and the consequent increased risk of oxidative-related systemic diseases.

Does psychological stress in patients with clinically suspect arthralgia associate with subclinical inflammation and progression to inflammatory arthritis?

PubMed

Boer, Aleid C; Ten Brinck, Robin M; Evers, Andrea W M; van der Helm-van Mil, Annette H M

2018-05-03

Within established rheumatoid arthritis (RA), stress can have pro-inflammatory effects by activating the immune system via the hypothalamic-pituitary-adrenal axis and the autonomic nervous system. It is unknown if stress levels also promote inflammation during RA development. We studied whether the psychological stress response was increased in clinically suspect arthralgia (CSA) and if this associated with inflammation at presentation with arthralgia and with progression to clinical arthritis. In 241 CSA patients, psychological stress was measured by the Mental Health Inventory (MHI-5) and the Perceived Stress Scale (PSS-10) at first presentation and during follow-up. Systemic inflammation was measured by C-reactive protein (CRP) and joint inflammation by 1.5 T-MRI of wrist, MCP, and MTP joints. At baseline, 12% (24/197) of CSA patients had a high psychological stress response according to the MHI-5. This was not different for patients presenting with or without an elevated CRP, with or without subclinical MRI-detected inflammation and for patients who did or did not develop arthritis. Similar findings were obtained with the PSS-10. When developing clinical arthritis, the percentage of patients with 'high psychological stress' increased to 31% (p = 0.025); during the first year of treatment this decreased to 8% (p = 0.020). 'High psychological stress' in non-progressors remained infrequent over time (range 7-13%). Stress was associated with fatigue (p = 0.003) and wellbeing (p < 0.001). Psychological stress was not increased in the phase of arthralgia, raised at the time of diagnoses and decreased thereafter. The lack of an association with inflammation in arthralgia and this temporal relationship, argue against psychological stress having a significant contribution to progression from CSA to inflammatory arthritis.

Perceived sources of stress among Malaysian dental students

PubMed Central

Hasan, Syed S.; Ooi, Yong J.; Ahmed, Syed I.; Wong, Pei S.; Ahmad, Siti F.; MNM-Rosdy, Nik M.; Malik, Normaliza A.

2015-01-01

Objectives The study objectives were to identify the stress levels and to explore the impact of students' year of study and gender on the perceived sources of stress among Malaysian dental students. Methods This was a cross-sectional study involving dental students from year one to year five from private and public universities in Malaysia. The study was formally approved by the Research and Ethics Committee, International Medical University Malaysia. Dental Environment Stress (DES) questionnaire was used for data collection and the gathered data were analyzed using SPSS® version 18. The Kruskal-Wallis and the Mann-Whitney U tests were used to compare stress items across various academic years and universities. Results A total of five hundred and twenty nine (529) students participated in this study. Fear of failing the course at the end of year exams (mean stress level=5.57); concerns regarding completion of clinical work (mean=5.30); and examination results and grades (mean=5.27) were found as top stressors among dental students. Female students had higher stress scores than males with respect to personal issues, academic performance, educational environment and learning of clinical skills. Students from public universities had higher stress scores than their counterparts from private universities. Conclusion The Malaysian dental students reported higher levels of stress. Present study identified stressors affecting dental students' academic life, and highlights the importance of stress management programs and other measures to minimize the impact of stress on both academic and personal lives of the students. PMID:25935506

Perceived sources of stress among Malaysian dental students.

PubMed

Babar, Muneer G; Hasan, Syed S; Ooi, Yong J; Ahmed, Syed I; Wong, Pei S; Ahmad, Siti F; Mnm-Rosdy, Nik M; Malik, Normaliza A

2015-05-02

The study objectives were to identify the stress levels and to explore the impact of students' year of study and gender on the perceived sources of stress among Malaysian dental students. This was a cross-sectional study involving dental students from year one to year five from private and public universities in Malaysia. The study was formally approved by the Research and Ethics Committee, International Medical University Malaysia. Dental Environment Stress (DES) questionnaire was used for data collection and the gathered data were analyzed using SPSS® version 18. The Kruskal-Wallis and the Mann-Whitney U tests were used to compare stress items across various academic years and universities. A total of five hundred and twenty nine (529) students participated in this study. Fear of failing the course at the end of year exams (mean stress level=5.57); concerns regarding completion of clinical work (mean=5.30); and examination results and grades (mean=5.27) were found as top stressors among dental students. Female students had higher stress scores than males with respect to personal issues, academic performance, educational environment and learning of clinical skills. Students from public universities had higher stress scores than their counterparts from private universities. The Malaysian dental students reported higher levels of stress. Present study identified stressors affecting dental students' academic life, and highlights the importance of stress management programs and other measures to minimize the impact of stress on both academic and personal lives of the students.

[German translation and validation of the Stress Appraisal Measure (SAM)].

PubMed

Delahaye, M; Stieglitz, R D; Graf, M; Keppler, C; Maes, J; Pflueger, M

2015-05-01

In the present study, the German-language version of the Stress Appraisal Measure (SAM) by Peacock and Wong was validated in a student population. SAM is a relatively short questionnaire (28 items) that evaluates a current, stress-triggering event. The theoretical background is provided by the stress model of Lazarus and Folkman. 85 students (age: 23; 59 female, 26 male) were exposed to two stress scenarios in order to test whether they were suited to provoke stress. A factor analysis was performed and the internal consistency of the seven SAM scales was determined. In addition, the convergent validity of SAM with State and Trait Anxiety Inventory (STAI), Coping Inventory for Stressful Situations (CISS) and specific emotion scales was investigated via Pearson's product-moment correlation. The two stress scenarios were suited to evoke stress. The factor structure and the internal consistency of the individual scales, as well as the convergent validity of SAM were replicated with minor limitations in the present German version. Some items (especially from the fifth factor) were only replicated partially. SAM can also be employed in the German language version. © Georg Thieme Verlag KG Stuttgart · New York.

The role of physical activity and heart rate variability for the control of work related stress.

PubMed

Tonello, Laís; Rodrigues, Fábio B; Souza, Jeniffer W S; Campbell, Carmen S G; Leicht, Anthony S; Boullosa, Daniel A

2014-01-01

Physical activity (PA) and exercise are often used as tools to reduce stress and therefore the risk for developing cardiovascular diseases (CVD). Meanwhile, heart rate variability (HRV) has been utilized to assess both stress and PA or exercise influences. The objective of the present review was to examine the current literature in regards to workplace stress, PA/exercise and HRV to encourage further studies. We considered original articles from known databases (PubMed, ISI Web of Knowledge) over the last 10 years that examined these important factors. A total of seven studies were identified with workplace stress strongly associated with reduced HRV in workers. Longitudinal workplace PA interventions may provide a means to improve worker stress levels and potentially cardiovascular risk with mechanisms still to be clarified. Future studies are recommended to identify the impact of PA, exercise, and fitness on stress levels and HRV in workers and their subsequent influence on cardiovascular health.

cStress: Towards a Gold Standard for Continuous Stress Assessment in the Mobile Environment

PubMed Central

Hovsepian, Karen; al’Absi, Mustafa; Ertin, Emre; Kamarck, Thomas; Nakajima, Motohiro; Kumar, Santosh

2015-01-01

Recent advances in mobile health have produced several new models for inferring stress from wearable sensors. But, the lack of a gold standard is a major hurdle in making clinical use of continuous stress measurements derived from wearable sensors. In this paper, we present a stress model (called cStress) that has been carefully developed with attention to every step of computational modeling including data collection, screening, cleaning, filtering, feature computation, normalization, and model training. More importantly, cStress was trained using data collected from a rigorous lab study with 21 participants and validated on two independently collected data sets — in a lab study on 26 participants and in a week-long field study with 20 participants. In testing, the model obtains a recall of 89% and a false positive rate of 5% on lab data. On field data, the model is able to predict each instantaneous self-report with an accuracy of 72%. PMID:26543926

Review of work-related stress in mainland Chinese nurses.

PubMed

Zeng, Yingchun

2009-03-01

The aim of this review was to identify the specific work-related stressors of mainland Chinese nurses and to present the current state of stress research in order to discuss directions for further research. A literature search from January 2000 to June 2007 was conducted among three electronic databases. The specific stressors among Chinese nurses were effort-reward imbalance, the poor image of nursing in the community, and managerial issues. The studies were limited to either descriptive or correlation designs, a variety of stress scales were used to investigate the nurses' work-related stressors, and there were no published studies reporting stress management interventions for Chinese nurses. This review highlights that further stress research targeted to Chinese nurses needs more prospective and longitudinal studies and has to develop a consistent instrument to measure stressors. The priority issue is the initiation of stress management interventions to improve nurses' coping skills, while the long-term goal is to reduce the level of stress or eliminate the stressors through individual, organizational, and societal interventions.

[Current State of Studies on Job-related Stress among Psychiatric Social Workers and Insights into Future Research].

PubMed

Yada, Hironori; Abe, Hiroshi; Odachi, Ryo; Iwanaga, Yasushi; Yamane, Toshie

2016-01-01

We studied the characteristics of psychiatric social workers (PSWs) and present research on job-related stress among them; we also provide insights into the future of such research. In recent years, studies on job-related stress among PSWs have been gaining interest. In particular, stress associated with the repeated revisions of related laws has increased. Subsequently, it was found that occupational stress in PSWs differs qualitatively and quantitatively depending on educational history, years of experience, and service department. However, no scale captures the specific characteristics of job-related stress among PSWs. Moreover, the development of a mental health care program for PSWs seems difficult. To develop a mental health care program that caters specifically to this group, future research should focus on developing a scale that determines the specific characteristics of job-related stress among PSWs, which should be evaluated on the basis of each PSW's educational history, years of experience, and service department.

Pilot Evaluation of the Feasibility and Acceptability of StressOFF Strategies: A Single-Session School-Based Stress Management Program for Adolescents

ERIC Educational Resources Information Center

Shapiro, Amy J.; Heath, Nancy L.; Carsley, Dana

2016-01-01

The present study reports the pilot evaluation of the feasibility and acceptability of StressOFF Strategies, a "single-session" (45 min) adolescent-targeted, school-based psychoeducational program, which introduces cognitive behavioral techniques and mindfulness-based techniques. Five hundred and sixty-five Grade 9 students (57% female;…

Coordinated decline in electron transport, PEP carboxylase activity, and maximal net CO2 assimilation with loss of hydraulic conductance during water stress in Zea mays

USDA-ARS?s Scientific Manuscript database

Maintaining high photosynthetic yield in water-stressed maize plants is a present priority for agriculture, and will likely increase in importance as key food producing regions become drier in the future. Although several physiological responses to water stress in maize have been studied in isolati...

Examining the Influence of Perceived Stress on Developmental Change in Memory and Perceptual Speed for Adopted and Nonadopted Individuals

ERIC Educational Resources Information Center

Ricker, Ashley A.; Corley, Robin; DeFries, John C.; Wadsworth, Sally J.; Reynolds, Chandra A.

2018-01-01

The present study prospectively evaluated cumulative early life perceived stress in relation to differential change in memory and perceptual speed from middle childhood to early adulthood. We aimed to identify periods of cognitive development susceptible to the effects of perceived stress among both adopted and nonadopted individuals. The sample…

Strategies for Coping with Stress: Case Histories of Four Women Scientists.

ERIC Educational Resources Information Center

Donnellan, LaRae M.

As a minority, women experience stress because of their gender when they enter the male-dominated profession of science. A review of the coping strategies used by women in dealing with the psychologically stressful situations of choosing a career in science is presented in this paper. This study is based on interviews with four women trained in…

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

ERIC Educational Resources Information Center

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…

Parenting Stress in Mothers of Children with an Intellectual Disability: The Effects of Parental Cognitions in Relation to Child Characteristics and Family Support

ERIC Educational Resources Information Center

Hassall, R.; Rose, J.; McDonald, J.

2005-01-01

Background: Recent theories of stress and coping in parents of children with intellectual disabilities (ID) emphasize the importance of cognitive appraisals in influencing parents' levels of stress and their adaptations to difficulties presented by the children. This study investigated the relationships between parental cognitions, child…

Stress, Locus of Control, and Family Cohesion and Adaptability in Parents of Children with Down, Williams, Fragile X, and Prader-Willi Syndromes

ERIC Educational Resources Information Center

Lanfranchi, Silvia; Vianello, Renzo

2012-01-01

The present study analyzes differences in parental stress in families of children with Down, Williams, Fragile X, and Prader-Willi syndromes, exploring factors that influence parental stress, such as child's characteristics, parental locus of control, and family cohesion and adaptability. Differences between mothers and fathers are also…

Contribution of mental workload to job stress in industrial workers.

PubMed

González-Muñoz, Elvia Luz; Gutiérrez-Martínez, Rodolfo E

2007-01-01

This study's central objective is to determine how several individual, organizational and ergonomic factors influence the relationship between job stress and mental workload for workers in an electronics company. A cross-sectional study was made as a test of hypotheses regarding that relationship. The sample is composed of 95 workers, of both sexes, from the electronics industry in the metropolitan zone of Guadalajara, Jalisco, Mexico. Ergonomic conditions were evaluated with the Ergonomic Evaluation List, stress was evaluated by administering the SWS-Survey to groups of subjects, and mental workload was evaluated with the NASA-TLX Workload Index. Using Cochran's and Mantel-Haenzsel statistics, the odds ratio for each of the independent variables was {e}stimated as a risk factor for job stress, and analysis was later conducted by means of logistic regression for those risks found to be significant. Of the 95 worker participants, 26.3% presented a high level of job stress and 17.9% of the workers were found to present high levels of mental workload. The results show that working hours, mental demand, temporal demand, and frustration when faced with a given task may be considered risk factors for job stress.

Association of job-related stress factors with psychological and somatic symptoms among Japanese hospital nurses: effect of departmental environment in acute care hospitals.

PubMed

Kawano, Yuri

2008-01-01

The present study examined degrees of job-related stress factors as well as mental and physical symptoms among Japanese hospital nurses in various departments, and clarified associations of departments and job-related stress factors with those symptoms. A self-administered anonymous questionnaire was distributed to 1,882 full-time nurses at four acute care hospitals in Japan. The survey included demographic factors, and the Brief Job Stress Questionnaire. Among 1,599 nurses who completed all items relevant to the present study, we analyzed data from 1,551 female nurses. The results show that working in operating rooms was associated with fatigue, that working in intensive care units (ICU) was associated with anxiety, and that working in surgery and internal medicine was associated with anxiety and depression independently of demographic factors and job-related stress factors. The physical and mental health of nurses might affect their time off, quality of nursing care and patient satisfaction in acute care hospitals. Therefore, job-related stress factors should be minimized, to improve the physical and mental health of nurses, considering unique departmental demands.

Adaptive capability as indicated by endocrine and biochemical responses of Malpura ewes subjected to combined stresses (thermal and nutritional) in a semi-arid tropical environment

NASA Astrophysics Data System (ADS)

Sejian, Veerasamy; Maurya, Vijai P.; Naqvi, Sayeed M. K.

2010-11-01

A study was conducted to assess the effect of combined stresses (thermal and nutritional) on endocrine and biochemical responses in Malpura ewes. Twenty eight adult Malpura ewes (average body weight 33.56 kg) were used in the present study. The ewes were divided into four groups viz., GI ( n = 7; control), GII ( n = 7; thermal stress), GIII ( n = 7; nutritional stress) and GIV ( n = 7; combined stress). The animals were stall fed with a diet consisting of 60% roughage and 40% concentrate. GI and GII ewes were provided with ad libitum feeding while GIII and GIV ewes were provided with restricted feed (30% intake of GI ewes) to induce nutritional stress. GII and GIV ewes were kept in climatic chamber at 40°C and 55% RH for 6 h a day between 1000 hours and 1600 hours to induce thermal stress. The study was conducted for a period of two estrus cycles. The parameters studied were Hb, PCV, glucose, total protein, total cholesterol, ACP, ALP, cortisol, T4, T3, and insulin. Combined stress significantly ( P < 0.05) affected all parameters studied. Furthermore, the results revealed that, compared to thermal stress, nutritional stress had a less significant effect on the parameters studied. However, when both these stresses were coupled, they had a severe impact on all the parameters studied in these ewes. It can be concluded from this study that two stressors occurring simultaneously may impact severely on the biological functions necessary to maintain homeostasis in sheep.

RNA-seq analysis of the head-kidney transcriptome response to handling-stress in the red cusk-eel (Genypterus chilensis).

PubMed

Aballai, Víctor; Aedo, Jorge E; Maldonado, Jonathan; Bastias-Molina, Macarena; Silva, Herman; Meneses, Claudio; Boltaña, Sebastian; Reyes, Ariel; Molina, Alfredo; Valdés, Juan Antonio

2017-12-01

Stress is a primary contributing factor of fish disease and mortality in aquaculture. We have previously reported that the red cusk-eel (Genypterus chilensis), an important farmed marine fish, demonstrates a handling-stress response that results in increased juvenile mortality, which is mainly associated with skeletal muscle atrophy and liver steatosis. To better understand the systemic effects of stress on red cusk-eel immune-related gene expression, the present study assessed the transcriptomic head-kidney response to handling-stress. The RNA sequencing generated a total of 61,655,525 paired-end reads from control and stressed conditions. De novo assembly using the CLC Genomic Workbench produced 86,840 transcripts and created a reference transcriptome with a N50 of 1426bp. Reads mapped onto the assembled reference transcriptome resulted in the identification of 569 up-regulated and 513 down-regulated transcripts. Gene ontology enrichment analysis revealed a significant up-regulation of the biological processes, like response to stress, response to biotic stimulus, and immune response. Conversely, a significant down-regulation of biological processes is associated with metabolic processes. These results were validated by RT-qPCR analysis for nine candidate genes involved in the immune response. The present data demonstrated that short term stress promotes the immune innate response in the marine teleost G. chilensis. This study is an important step towards understanding the immune adaptive response to stress in non-model teleost species. Copyright © 2017 Elsevier Inc. All rights reserved.

Treatment of stress fracture of the olecranon in throwing athletes with internal fixation through a small incision

PubMed Central

2012-01-01

The present study is a report of retrospective case series of stress fracture of the olecranon. Six patients presented posterior elbow pain in throwing in baseball and softball, but fracture was not diagnosed in radiographs. We detected stress fracture of the olecranon using computed tomographic (CT) scan and treated the patient with internal fixation with a headless cannulated double threaded screw through a small skin incision. All patients returned to competitive level without elbow complaints after the operation. When throwing athletes present with unusual posterior elbow pain and no significant findings on radiographs, a CT scan examination should be performed. We recommend surgical treatment of internal fixation with a screw through a small skin incision, as a good option for stress fracture of the olecranon in order to allow early return to sports activity in competitive athletes. PMID:23241173

Combined effect of water loss and wounding stress on gene activation of metabolic pathways associated with phenolic biosynthesis in carrot

PubMed Central

Becerra-Moreno, Alejandro; Redondo-Gil, Mónica; Benavides, Jorge; Nair, Vimal; Cisneros-Zevallos, Luis; Jacobo-Velázquez, Daniel A.

2015-01-01

The application of postharvest abiotic stresses is an effective strategy to activate the primary and secondary metabolism of plants inducing the accumulation of antioxidant phenolic compounds. In the present study, the effect of water stress applied alone and in combination with wounding stress on the activation of primary (shikimic acid) and secondary (phenylpropanoid) metabolic pathways related with the accumulation of phenolic compound in plants was evaluated. Carrot (Daucus carota) was used as model system for this study, and the effect of abiotic stresses was evaluated at the gene expression level and on the accumulation of metabolites. As control of the study, whole carrots were stored under the same conditions. Results demonstrated that water stress activated the primary and secondary metabolism of carrots, favoring the lignification process. Likewise, wounding stress induced higher activation of the primary and secondary metabolism of carrots as compared to water stress alone, leading to higher accumulation of shikimic acid, phenolic compounds, and lignin. Additional water stress applied on wounded carrots exerted a synergistic effect on the wound-response at the gene expression level. For instance, when wounded carrots were treated with water stress, the tissue showed 20- and 14-fold increases in the relative expression of 3-deoxy-D-arabino-heptulosanate synthase and phenylalanine ammonia-lyase genes, respectively. However, since lignification was increased, lower accumulation of phenolic compounds was detected. Indicatively, at 48 h of storage, wounded carrots treated with water stress showed ~31% lower levels of phenolic compounds and ~23% higher lignin content as compared with wounded controls. In the present study, it was demonstrated that water stress is one of the pivotal mechanism of the wound-response in carrot. Results allowed the elucidation of strategies to induce the accumulation of specific primary or secondary metabolites when plants are treated with water stress alone or when additional water stress is applied on wounded tissue. If the accumulation of a specific primary or secondary metabolite were desirable, it would be recommended to apply both stresses to accelerate their biosynthesis. However, strategies such as the use of enzymatic inhibitors to block the carbon flux and enhance the accumulation of specific compounds should be designed. PMID:26528305

Effects of centrifugation on gonadal and adrenocortical steroids in rats

NASA Technical Reports Server (NTRS)

Kakihana, R.; Butte, J. C.

1980-01-01

Many endocrine systems are sensitive to external changes in the environment. Both the pituitary adrenal and pituitary gonadal systems are affected by stress including centrifugation stress. The effect of centrifugation on the pituitary gonadal and pituitary adrenocortical systems was examined by measuring the gonadal and adrenal steroids in the plasma and brain following different duration and intensity of centrifugation stress in rats. Two studies were completed and the results are presented. The second study was carried out to describe the developmental changes of brain, plasma and testicular testosterone and dihydrotestosterone in Sprague Dawley rats so that the effect of centrifugation stress on the pituitary gonadal syatem could be better evaluated in future studies.

Reynolds-Stress Budgets in an Impinging Shock Wave/Boundary-Layer Interaction

NASA Technical Reports Server (NTRS)

Vyas, Manan A.; Yoder, Dennis A.; Gaitonde, Datta V.

2018-01-01

Implicit large-eddy simulation (ILES) of a shock wave/boundary-layer interaction (SBLI) was performed. Comparisons with experimental data showed a sensitivity of the current prediction to the modeling of the sidewalls. This was found to be common among various computational studies in the literature where periodic boundary conditions were used in the spanwise direction, as was the case in the present work. Thus, although the experiment was quasi-two-dimensional, the present simulation was determined to be two-dimensional. Quantities present in the exact equation of the Reynolds-stress transport, i.e., production, molecular diffusion, turbulent transport, pressure diffusion, pressure strain, dissipation, and turbulent mass flux were calculated. Reynolds-stress budgets were compared with past large-eddy simulation and direct numerical simulation datasets in the undisturbed portion of the turbulent boundary layer to validate the current approach. The budgets in SBLI showed the growth in the production term for the primary normal stress and energy transfer mechanism was led by the pressure strain term in the secondary normal stresses. The pressure diffusion term, commonly assumed as negligible by turbulence model developers, was shown to be small but non-zero in the normal stress budgets, however it played a key role in the primary shear stress budget.

Theory Of Dewetting In A Filled Elastomer Under Stress

NASA Technical Reports Server (NTRS)

Peng, Steven T. J.

1993-01-01

Report presents theoretical study of dewetting between elastomeric binder and filler particles of highly filled elastomer under multiaxial tension and resulting dilatation of elastomer. Study directed toward understanding and predicting nonlinear stress-vs.-strain behavior of filled elastomeric rocket propellant, also applicable to rubber in highly loaded tire or in damping pad.

Coping With Pain: Studies in Stress Inoculation.

ERIC Educational Resources Information Center

Horan, John J.; And Others

The stress-inoculation paradigm for helping clients deal with pain consists of education about the psychological dimensions of pain, training in a number of coping skills relevant to each dimension, and practice in applying these skills to the noxious stimulus. Presented are two studies, the first of which represents a component analysis of stress…

Technostress in Libraries and Media Centers: Case Studies and Coping Strategies.

ERIC Educational Resources Information Center

Hickey, Kate D., Ed.

1992-01-01

Discusses technostress--i.e., stress brought on by changes in technology--in libraries and media centers. Case studies are presented that show stress in community college libraries caused by the rapid implementation of new technologies; coping strategies for librarians and media specialists are discussed; and strategies for managers are suggested.…

The Relationship Between Stressful Life Events, Locus of Control, and Suicidal Ideation.

ERIC Educational Resources Information Center

Crepeau, James J.

Numerous studies involving suicide attempters and those who commit suicide suggest that the suicidal individual perceives limited control over the environment, the occurrence of stressful life events and a diminished probability of future success. Results of the present study indicate a relationship between the frequency of suicidal thoughts among…

Traumatic Stress Symptoms and Breast Cancer: The Role of Childhood Abuse

ERIC Educational Resources Information Center

Goldsmith, Rachel E.; Jandorf, Lina; Valdimarsdottir, Heiddis; Amend, Kandace L.; Stoudt, Brett G.; Rini, Christine; Hershman, Dawn; Neugut, Alfred; Reilly, James J.; Tartter, Paul I.; Feldman, Sheldon M.; Ambrosone, Christine B.; Bovbjerg, Dana H.

2010-01-01

Objective: The present study investigated relations between reported childhood abuse and recent traumatic stress symptoms in women newly diagnosed with breast cancer (n = 330). Methods: As part of a larger ongoing study, patients from eight public and private hospitals were referred by their physicians and completed the Childhood Trauma…

Have University Sport Students Higher Scores Depression, Anxiety and Psychological Stress?

ERIC Educational Resources Information Center

Demirel, Havva

2016-01-01

Multiple studies have now shown that people who maintain appropriate body fitness, using judicious regimens of exercise and weight control, have the additional benefit of prolonged life. In fact, sport or exercise may be also expected to be helpful for psychological health. In the present study, depression, anxiety and psychological stress points…

Association among Working Hours, Occupational Stress, and Presenteeism among Wage Workers: Results from the Second Korean Working Conditions Survey.

PubMed

Jeon, Sung-Hwan; Leem, Jong-Han; Park, Shin-Goo; Heo, Yong-Seok; Lee, Bum-Joon; Moon, So-Hyun; Jung, Dal-Young; Kim, Hwan-Cheol

2014-03-24

The purpose of the present study was to identify the association between presenteeism and long working hours, shiftwork, and occupational stress using representative national survey data on Korean workers. We analyzed data from the second Korean Working Conditions Survey (KWCS), which was conducted in 2010, in which a total of 6,220 wage workers were analyzed. The study population included the economically active population aged above 15 years, and living in the Republic of Korea. We used the chi-squared test and multivariate logistic regression to test the statistical association between presenteeism and working hours, shiftwork, and occupational stress. Approximately 19% of the workers experienced presenteeism during the previous 12 months. Women had higher rates of presenteeism than men. We found a statistically significant dose-response relationship between working hours and presenteeism. Shift workers had a slightly higher rate of presenteeism than non-shift workers, but the difference was not statistically significant. Occupational stress, such as high job demand, lack of rewards, and inadequate social support, had a significant association with presenteeism. The present study suggests that long working hours and occupational stress are significantly related to presenteeism.

Association among Working Hours, Occupational Stress, and Presenteeism among Wage Workers: Results from the Second Korean Working Conditions Survey

PubMed Central

2014-01-01

Objectives The purpose of the present study was to identify the association between presenteeism and long working hours, shiftwork, and occupational stress using representative national survey data on Korean workers. Methods We analyzed data from the second Korean Working Conditions Survey (KWCS), which was conducted in 2010, in which a total of 6,220 wage workers were analyzed. The study population included the economically active population aged above 15 years, and living in the Republic of Korea. We used the chi-squared test and multivariate logistic regression to test the statistical association between presenteeism and working hours, shiftwork, and occupational stress. Results Approximately 19% of the workers experienced presenteeism during the previous 12 months. Women had higher rates of presenteeism than men. We found a statistically significant dose–response relationship between working hours and presenteeism. Shift workers had a slightly higher rate of presenteeism than non-shift workers, but the difference was not statistically significant. Occupational stress, such as high job demand, lack of rewards, and inadequate social support, had a significant association with presenteeism. Conclusions The present study suggests that long working hours and occupational stress are significantly related to presenteeism. PMID:24661575

Influence of fracture extension on in-situ stress in tight reservoir

NASA Astrophysics Data System (ADS)

Zhang, Yongping; Wei, Xu; Zhang, Ye; Xing, Libo; Xu, Jianjun

2018-01-01

Currently, hydraulic fracturing is an important way to develop low permeability reservoirs. The fractures produced during the fracturing process are the main influencing factors of changing in-situ stress. In this paper, the influence of fracture extension on in-situ stress is studied by establishing a mathematical model to describe the relationship between fracture length and in-situ stress. The results show that the growth rate gradually decreases after the fracture reaches a certain length with the increase of fracturing time; the continuous extension of the fracture is the main factor to change the in-situ stress. In order to reduce the impact on the subsequent fracture extension due to the changing of in-situ stress, controlling fracturing time and fracture length without affecting the stimulated reservoir effect is an important way. The results presented in this study can effectively reduce the impact of changing of in-situ stress on subsequent fracturing construction.

Couple-level Minority Stress: An Examination of Same-sex Couples' Unique Experiences.

PubMed

Frost, David M; LeBlanc, Allen J; de Vries, Brian; Alston-Stepnitz, Eli; Stephenson, Rob; Woodyatt, Cory

2017-12-01

Social stress resulting from stigma, prejudice, and discrimination-"minority stress"-negatively impacts sexual minority individuals' health and relational well-being. The present study examined how being in a same-sex couple can result in exposure to unique minority stressors not accounted for at the individual level. Relationship timeline interviews were conducted with 120 same-sex couples equally distributed across two study sites (Atlanta and San Francisco), gender (male and female), and relationship duration (at least six months but less than three years, at least three years but less than seven years, and seven or more years). Directed content analyses identified 17 unique couple-level minority stressors experienced within nine distinct social contexts. Analyses also revealed experiences of dyadic minority stress processes (stress discrepancies and stress contagion). These findings can be useful in future efforts to better understand and address the cumulative impact of minority stress on relational well-being and individual health.

Correlation of Rupture Life, Creep Rate, and Microstructure for Type 304 Stainless Steel

NASA Technical Reports Server (NTRS)

Swindeman, R. W.; Moteff, J.

1983-01-01

The stress and temperature sensitivites of the rupture life and secondary creep rate were examined in detail for a single heat of type 304 stainless steel (9T2796). Assuming that the rupture life has a power law stress dependency, relatively small differences in the stress exponent were observed over a broad range of stress and temperature. In contrast, large changes were observed for equivalent parameter for secondary creep rate. As a result of these differences, the Monkman-Grant correlation was sensitive to stress and temperature below 650 C. Metallurgical studies based on light and transmission electron microscopy suggested that the temperature and stress sensitivities of secondary creep rate at temperatures below 650 C were related to features of the substructure not present at higher temperature. Specifically, the presence of a fine dislocation network stabilized by precipitates altered the stress and temperature sensitivities relative to what might be expected from high temperature studies.

A study of the use of vibration and stress wave sensing for the detection of bearing failure

NASA Technical Reports Server (NTRS)

Ensor, L. C.; Feng, C. C.

1975-01-01

Results from an experimental study of vibrations and stress waves emitted from ball bearings are presented. Fatique tests were run with both high quality bearings and man faulted bearings, all of one size. Tests were instrumented with different sensors to detect the noises from 10 Hz to 1 MHz. Frequency spectrum plots are presented. The modulation characteristics of the ultrasonic noises were analyzed, and acoustic emission type measurements were conducted. Results are presented which show that there are usable acoustic signal levels even beyond 500 KHz. These signal levels are modulated by a low frequency carrier which is a function of the stress loading and acoustic transmissibility. The results were correlated to fault size in the bearings. The correlation shows that the sensor used for signals from 100 KHz to 1 MHz gave the best sensitivity and detected the generation of very small spalls or pits.

Physiological effects of handling and hauling stress on smallmouth bass

USGS Publications Warehouse

Carmichael, G.J.; Wedemeyer, G.A.; McCraren, J.P.; Millard, J.L.

1983-01-01

Basic physiological information on the stress caused by current hatchery practices is helpful in developing new and improved techniques to increase survival. In view of the present fishery management requirements for stocking smallmouth bas (Micropterus dolomieu), baseline information on the physiological effects of handling and hauling hatchery-reared fish is needed to serve as the foundation for improving transport methods. Shell (1959) summarized several physiological characteristics of smallmouth bass, but little information on their physiological tolerance to stress exists. The present study was designed to determine the physiological effects of handling and short-term hauling in small mouth bass. Plasma chloride, sodium, potassium, and glucose dynamics were monitored in indicate the severity of the resulting stress and the recovery time needed.

Analysis of thermoelastic characteristics in a thick walled FGM cylinder

NASA Astrophysics Data System (ADS)

Tanvir, A. N. M.; Islam, Md. Didarul; Ahmed, Faisal

2017-12-01

This study is concerned with the behavior of stress and strain in a thick walled functionally graded material (FGM) cylinder under internal pressure. The incompatible eigenstrain and equivalent eigenstrain developed in the cylinder, are taken into account. As a demonstration, a TiC/Al2O3 FGM cylinder is considered and different components of stress and strain are presented in order to study the effects of internal pressure, temperature difference (between room and sintering temperature), cylinder wall thickness and material distribution. The numerical result presented here shows that the thermoelastic characteristic like stress and strain of an FGM cylinder is significantly influenced by some of the above-mentioned parameters and can be controlled by properly controlling these parameters.

Modeling of Wall-Bounded Complex Flows and Free Shear Flows

NASA Technical Reports Server (NTRS)

Shih, Tsan-Hsing; Zhu, Jiang; Lumley, John L.

1994-01-01

Various wall-bounded flows with complex geometries and free shear flows have been studied with a newly developed realizable Reynolds stress algebraic equation model. The model development is based on the invariant theory in continuum mechanics. This theory enables us to formulate a general constitutive relation for the Reynolds stresses. Pope was the first to introduce this kind of constitutive relation to turbulence modeling. In our study, realizability is imposed on the truncated constitutive relation to determine the coefficients so that, unlike the standard k-E eddy viscosity model, the present model will not produce negative normal stresses in any situations of rapid distortion. The calculations based on the present model have shown an encouraging success in modeling complex turbulent flows.

Stress field modelling from digital geological map data

NASA Astrophysics Data System (ADS)

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 calculated from the fracture criterion. The calculation includes the gravitational acceleration, the average density of rocks and the experimental 60 degree of the fracture angle from the normal of the fault plane. This way, the stress tensors are calculated as absolute pressure values per square meters on both sides of the faults. If the stress from the overburden is greater than 1 bar (i.e. the faults are buried), a confined compression would be present. Modelling this state of stress may result a confusing pattern of vectors, because in a confined position the horizontal stress vectors may point towards structures primarily associated with extension. To step over this, and to highlight the variability in the stress-field, the model calculates the vectors directly from the differential stress (practically subtracting the minimum principal stress from the critical stress). The result of the modelling is a vector map, which theoretically represents the minimum tectonic pressure in the moment, when the rock body breaks from an initial state. This map - together with the original fault-map - is suitable for determining those areas where unrevealed tectonic, sedimentary and lithological structures are possibly present (e.g. faults, sub-basins and intrusions). With modelling different deformational phases on the same area, change of the stress vectors can be detected which reveals not only the varying directions of the principal stresses, but the tectonic-driven sedimentation patterns too. The decrease of necessary critical stress in the case of a possible reactivation of a fault in subsequent deformation phase can be managed with the down-ranking of the concerning structural elements. Reference: Albert G., Ungvári ZS., Szentpéteri K. 2014: Modeling the present day stress field of the Pannonian Basin from neotectonic maps - In: Beqiraj A, Ionescu C, Christofides G, Uta A, Beqiraj Goga E, Marku S (eds.) Proceedings XX Congress of the Carpathian-Balkan Geological Association. Tirana: p. 2.

Non-Euclidean stress-free configuration of arteries accounting for curl of axial strips sectioned from vessels.

PubMed

Takamizawa, Keiichi; Nakayama, Yasuhide

2013-11-01

It is well known that arteries are subject to residual stress. In earlier studies, the residual stress in the arterial ring relieved by a radial cut was considered in stress analysis. However, it has been found that axial strips sectioned from arteries also curled into arcs, showing that the axial residual stresses were relieved from the arterial walls. The combined relief of circumferential and axial residual stresses must be considered to accurately analyze stress and strain distributions under physiological loading conditions. In the present study, a mathematical model of a stress-free configuration of artery was proposed using Riemannian geometry. Stress analysis for arterial walls under unloaded and physiologically loaded conditions was performed using exponential strain energy functions for porcine and human common carotid arteries. In the porcine artery, the circumferential stress distribution under physiological loading became uniform compared with that without axial residual strain, whereas a gradient of axial stress distribution increased through the wall thickness. This behavior showed almost the same pattern that was observed in a recent study in which approximate analysis accounting for circumferential and axial residual strains was performed, whereas the circumferential and axial stresses increased from the inner surface to the outer surface under a physiological condition in the human common carotid artery of a two-layer model based on data of other recent studies. In both analyses, Riemannian geometry was appropriate to define the stress-free configurations of the arterial walls with both circumferential and axial residual strains.

Application of mean wall shear stress boundary condition to complex turbulent flows using a wall-modeled large eddy simulation

NASA Astrophysics Data System (ADS)

Cho, Minjeong; Lee, Jungil; Choi, Haecheon

2012-11-01

The mean wall shear stress boundary condition was successfully applied to turbulent channel and boundary flows using large eddy simulation without resolving near-wall region (see Lee, Cho & Choi in this book of abstracts). In the present study, we apply this boundary condition to more complex flows where flow separation and redeveloping flow exist. As a test problem, we consider flow over a backward-facing step at Reh = 22860 based on the step height. Turbulent boundary layer flow at the inlet (Reθ = 1050) is obtained using inflow generation technique by Lund et al. (1998) but with wall shear stress boundary condition. First, we prescribe the mean wall shear stress distribution obtained from DNS (Kim, 2011, Ph.D. Thesis, Stanford U.) as the boundary condition of present simulation. Here we give no-slip boundary condition at flow-reversal region. The present results are in good agreements with the flow statistics by DNS. Currently, a dynamic approach of obtaining mean wall shear stress based on the log-law is being applied to the flow having flow separation and its results will be shown in the presentation. Supported by the WCU and NRF programs.

Extremity movements help occupational therapists identify stress responses in preterm infants in the neonatal intensive care unit: a systematic review.

PubMed

Holsti, Liisa; Grunau, Ruth E

2007-06-01

Accurate assessment and treatment of pain and stress in preterm infants in neonatal intensive care units (NICU) is vital because pain and stress responses have been linked to long-term alterations in development in this population. To review the evidence of specific extremity movements in preterm infants as observed during stressful procedures. Five on-line databases were searched for relevant studies. For each study, levels of evidence were determined and effect size estimates were calculated. Each study was also evaluated for specific factors that presented potential threats to its validity. Eighteen studies were identified and seven comprised the review. The combined sample included 359 preterm infants. Six specific movements were associated with painful and intrusive procedures. A set of specific extremity movements, when combined with other reliable biobehavioural measures of pain and stress, can form the basis for future research and development of a clinical stress scale for preterm infants.

Problem solving moderates the effects of life event stress and chronic stress on suicidal behaviors in adolescence.

PubMed

Grover, Kelly E; Green, Kelly L; Pettit, Jeremy W; Monteith, Lindsey L; Garza, Monica J; Venta, Amanda

2009-12-01

The present study examined the unique and interactive effects of stress and problem-solving skills on suicidal behaviors among 102 inpatient adolescents. As expected, life event stress and chronic stress each significantly predicted suicidal ideation and suicide attempt. Problem solving significantly predicted suicidal ideation, but not suicide attempt. Problem solving moderated the associations between life event stress and suicidal behaviors, as well as between chronic stress and suicidal ideation, but not chronic stress and suicide attempt. At high levels of stress, adolescents with poor problem-solving skills experienced elevated suicidal ideation and were at greater risk of making a nonfatal suicide attempt. The interactive effects decreased to non-significance after controlling for depressive symptoms and hopelessness. Clinical implications are discussed.

No evidence for differential dose effects of hydrocortisone on intrusive memories in female patients with complex post-traumatic stress disorder--a randomized, double-blind, placebo-controlled, crossover study.

PubMed

Ludäscher, Petra; Schmahl, Christian; Feldmann, Robert E; Kleindienst, Nikolaus; Schneider, Miriam; Bohus, Martin

2015-10-01

Post-traumatic stress disorder is characterized by intrusive traumatic memories. Presently, a controversial debate is ongoing regarding whether reduced cortisol secretion in post-traumatic stress disorder promotes an automatic retrieval of trauma-associated memories. Hence, a pharmacological elevation of cortisol was proposed to decrease post-traumatic stress disorder symptoms, particularly intrusions. The present study investigated the impact of two different doses of hydrocortisone on automatic memory retrieval using a randomized, double-blind, placebo-controlled, crossover study in 30 inpatients with post-traumatic stress disorder. All participants were female and received various psychotropic medications. They were randomly assigned to one of two groups within a crossover design: they received either 1 week placebo followed by 1 week hydrocortisone 10/d, followed by 1 week placebo, followed by hydrocortisone 30 mg/d (15 participants) or 1 week hydrocortisone 30 mg/d, followed by 1 week placebo, followed by 1 week hydrocortisone 10 mg/d, followed by 1 week placebo (15 participants). The outcome measures were the frequency and the intensity of intrusions, the overall symptomatology of post-traumatic stress disorder and the general psychopathology. We did not find any differences in the frequency and the intensity of post-traumatic stress disorder-related intrusions between the 10 mg hydrocortisone, the 30 mg hydrocortisone and the placebo condition. All effect sizes for the hydrocortisone condition vs. placebo were very small. Additionally, the overall symptomatology of post-traumatic stress disorder and the general psychopathology did not differ between the hydrocortisone therapies and placebo. Our results do not show any effect of the hydrocortisone administration on intrusions in complex post-traumatic stress disorder. © The Author(s) 2015.

On the role of heat flow, lithosphere thickness and lithosphere density on gravitational potential stresses

NASA Astrophysics Data System (ADS)

Pascal, Christophe

2006-10-01

Gravitational potential stresses (GPSt) are known to play a first-order role in the state of stress of the Earth's lithosphere. Previous studies focussed mainly on crust elevation and structure and little attention has been paid to modelling GPSt using realistic lithospheric structures. The aim of the present contribution is to quantify gravitational potential energies and stresses associated with stable lithospheric domains. In order to model realistic lithosphere structures, a wide variety of data are considered: surface heat flow, chemical depletion of mantle lithosphere, crustal thickness and elevation. A numerical method is presented which involves classical steady-state heat equations to derive lithosphere thickness, geotherm and density distribution, but additionally requires the studied lithosphere to be isostatically compensated at its base. The impact of varying surface and crustal heat flow, topography, Moho depth and crust density on the signs and magnitudes of predicted GPSt is systematically explored. In clear contrast with what is assumed in most previous studies, modelling results show that the density structure of the mantle lithosphere has a significant impact on the value of the predicted GPSt, in particular in the case of thick lithospheres. Using independent information from the literature, the method was applied to get insights in the state of stress of continental domains with contrasting tectono-thermal ages. The modelling results suggest that in the absence of tectonic stresses Phanerozoic and Proterozoic lithospheres are spontaneously submitted to compression whereas Archean lithospheres are in a neutral to slightly tensile stress state. These findings are in general in good agreement with global stress measurements and observed geoid undulations.

Increases in anxiety-like behavior induced by acute stress are reversed by ethanol in adolescent but not adult rats.

PubMed

Varlinskaya, Elena I; Spear, Linda P

2012-01-01

Repeated exposure to stressors has been found to increase anxiety-like behavior in laboratory rodents, with the social anxiety induced by repeated restraint being extremely sensitive to anxiolytic effects of ethanol in both adolescent and adult rats. No studies, however, have compared social anxiogenic effects of acute stress or the capacity of ethanol to reverse this anxiety in adolescent and adult animals. Therefore, the present study was designed to investigate whether adolescent [postnatal day (P35)] Sprague-Dawley rats differ from their adult counterparts (P70) in the impact of acute restraint stress on social anxiety and in their sensitivity to the social anxiolytic effects of ethanol. Animals were restrained for 90 min, followed by examination of stress- and ethanol-induced (0, 0.25, 0.5, 0.75, and 1 g/kg) alterations in social behavior using a modified social interaction test in a familiar environment. Acute restraint stress increased anxiety, as indexed by reduced levels of social investigation at both ages, and decreased social preference among adolescents. These increases in anxiety were dramatically reversed among adolescents by acute ethanol. No anxiolytic-like effects of ethanol emerged following restraint stress in adults. The social suppression seen in response to higher doses of ethanol was reversed by restraint stress in animals of both ages. To the extent that these data are applicable to humans, the results of the present study provide some experimental evidence that stressful life events may increase the attractiveness of alcohol as an anxiolytic agent for adolescents. Copyright © 2011 Elsevier Inc. All rights reserved.

Job stress, recognition, job performance and intention to stay at work among Jordanian hospital nurses.

PubMed

AbuAlRub, Raeda Fawzi; Al-Zaru, Ibtisam Moawiah

2008-04-01

To investigate: (1) relationships between job stress, recognition of nurses' performance, job performance and intention to stay among hospital nurses; and (2) the buffering effect of recognition of staff performance on the 'stress-intention to stay at work' relationship. Workplace stress tremendously affects today's workforce. Recognition of nurses' performance needs further investigation to determine if it enhances the level of intention to stay at work and if it can buffer the negative effects of stress on nurses' intention to stay at work. The sample of the present study was a convenience one. It consisted of 206 Jordanian staff nurses who completed a structured questionnaire. The findings of the study indicated a direct and a buffering effect of recognition of nurses' performance on job stress and the level of intention to stay at work. The results of the study indicated the importance of recognition for outstanding performance as well as achievements. Implications for nursing management The results of this study support the need to focus on the implementation of recognition strategies in the workplace to reduce job stress and enhance retention.

Alleviation of cadmium stress in Solanum lycopersicum L. by arbuscular mycorrhizal fungi via induction of acquired systemic tolerance

PubMed Central

Hashem, Abeer; Abd_Allah, E.F.; Alqarawi, A.A.; Al Huqail, Asma A.; Egamberdieva, D.; Wirth, S.

2015-01-01

Experiments were conducted to evaluate cadmium (Cd) stress-induced changes in growth, antioxidants and lipid composition of Solanum lycopersicum with and without arbuscular mycorrhizal fungi (AMF). Cadmium stress (50 μM) caused significant changes in the growth and physio-biochemical attributes studied. AMF mitigated the deleterious impact of Cd on the parameters studied. Cadmium stress increased malonaldehyde and hydrogen peroxide production but AMF reduced these parameters by mitigating oxidative stress. The activity of antioxidant enzymes enhanced under Cd treatment and AMF inoculation further enhanced their activity, thus strengthening the plant’s defense system. Proline and phenol content increased in Cd-treated as well as AMF-inoculated plants providing efficient protection against Cd stress. Cadmium treatment resulted in great alterations in the main lipid classes leading to a marked change in their composition. Cadmium stress caused a significant reduction in polyunsaturated fatty acids resulting in enhanced membrane leakage. The present study supports the use of AMF as a biological means to ameliorate Cd stress-induced changes in tomato. PMID:26981010

Long-term variability of sleep bruxism and psychological stress in patients with jaw-muscle pain: Report of two longitudinal clinical cases.

PubMed

Muzalev, K; Visscher, C M; Koutris, M; Lobbezoo, F

2018-02-01

Sleep bruxism (SB) and psychological stress are commonly considered as contributing factors in the aetiology of temporomandibular disorder (TMD) pain. However, the lack of longitudinal studies and fluctuating nature of SB, psychological stress and TMD pain have led to contradictory results regarding the association between the possible aetiological factors and TMD pain. In the present study we investigated the contribution of SB and psychological stress to TMD pain in a longitudinal study of 2 clinical TMD pain cases during a 6-week study protocol. Two female volunteers with clinically diagnosed myalgia based on the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) participated in the study. Questionnaires were used to record jaw-muscle pain and psychological stress experience, and an ambulatory polysomnography technique was used to record SB intensity. Visual analysis of the data revealed that the intensity of TMD pain was not hardwired, neither with psychological stress experience nor with increased SB activity. Within the limitations of single-patient clinical cases design, our study suggested that the presence of TMD pain cannot be explained by a simple linear model which takes psychological stress or SB into account. It also seems that psychological stress was a more important predictor factor for TMD pain than SB. © 2017 John Wiley & Sons Ltd.

[Heart Rate Variability as an Indicator of Mental Stress in Surgeons - A Review of the Literature].

PubMed

Thielmann, B; Boeckelmann, I

2016-10-01

The risk assessment of mental stress and early detection of mental illness among surgeons are much debated issues, because the perceived working conditions are important for their own health and that of the patients. Studies of predominantly mental stress are increasing and stay up-to-date. The psychological strain of surgeons is generally regarded as high. In order to objectively determine stress, the heart rate and its variability have been established as parameters. Based on the physiological stress parameter, it is possible to determine the previous level of strain. This work presents a summary of recent scientific studies to explore the stress in operative surgeons on the basis of the physiological stress parameters heart rate (HR) and heart rate variability (HRV). A PubMed search until spring of 2014 was performed. A total of 10 studies were included which deal with the mental stress and strain analysis by surgeons. In this case, 4 studies used only the HR and the further 6 studies used the HRV as a stress parameter. First stress and strain analyses of surgeons have been around since the early 1980s. The studies were usually carried out solely within the sample examined. Control groups have rarely or not been studied. In summary, stressed surgeons offered a higher intraoperative heart rate and a low expression of the HRV. The same was experienced in operating surgeons compared to the assistant surgeons or with inexperienced operating surgeons compared to experienced surgeons. Georg Thieme Verlag KG Stuttgart · New York.

Enhanced Stress Response in 5-HT1AR Overexpressing Mice: Altered HPA Function and Hippocampal Long-Term Potentiation.

PubMed

Pilar-Cuéllar, Fuencisla; Vidal, Rebeca; Díaz, Álvaro; Garro-Martínez, Emilio; Linge, Raquel; Castro, Elena; Haberzettl, Robert; Fink, Heidrun; Bert, Bettina; Brosda, Jan; Romero, Beatriz; Crespo-Facorro, Benedicto; Pazos, Ángel

2017-11-15

Postsynaptic 5-HT 1A receptors (5-HT 1A R) play an important role in anxiety and stress, although their contribution is still controversial. Previous studies report that mice overexpressing postsynaptic 5-HT 1A Rs show no changes in basal anxiety, though the influence of stress conditions has not been addressed yet. In this study, we used this animal model to evaluate the role of 5-HT 1A Rs in anxiety response after pre-exposure to an acute stressor. Under basal conditions, 5-HT 1A R overexpressing animals presented high corticosterone levels and a lower mineralocorticoid/glucocorticoid receptor ratio. After pre-exposure to a single stressor, they showed a high anxiety-like response, associated with a blunted increase in corticosterone levels and higher c-Fos activation in the prefrontal cortex. Moreover, these mice also presented a lack of downregulation of hippocampal long-term potentiation after stress exposure. Therefore, higher postsynaptic 5-HT 1A R activation might predispose to a high anxious phenotype and an impaired stress coping behavior.

Prevalence of depression, anxiety, and stress among young male adults in India: a dimensional and categorical diagnoses-based study.

PubMed

Sahoo, Saddichha; Khess, Christoday R J

2010-12-01

The lifetime prevalence of depression, anxiety, and stress among adolescents and young adults around the world is currently estimated to range from 5% to 70%, with an Indian study reporting no depression among college going adolescents. This cross-sectional study was conducted to determine prevalence of current depressive, anxiety, and stress-related symptoms on a Dimensional and Categorical basis among young adults in Ranchi city of India. A stratified sample of 500 students was selected to be representative of the city's college going population (n = 50,000) of which 405 were taken up for final analysis. Data were obtained using Depression, Anxiety, and Stress Scale to assess symptoms on dimensional basis and using Mini International Neuropsychiatric Interview to diagnose on categorical basis. Mean age of students was 19.3 years with an average education of 14.7 years. Ranging from mild to extremely severe, depressive symptoms were present in 18.5% of the population, anxiety in 24.4%, and stress in 20%. Clinical depression was present in 12.1% and generalized anxiety disorder in 19.0%. Comorbid anxiety and depression was high, with about 87% of those having depression also suffering from anxiety disorder. Detecting depressive, anxiety, and stress-related symptoms in the college population is a critical preventive strategy, which can help in preventing disruption to the learning process. Health policies must integrate young adults' depression, stress, and anxiety as a disorder of public health significance.

The Effects of Discrimination Experience on Life Satisfaction of North Korean Refugees: Mediating Effect of Stress.

PubMed

Noh, Jin-Won; Park, Hyunchun; Kim, Minji; Kwon, Young Dae; Kim, Jin-Seok; Yu, Shieun

2018-01-01

This study investigated the mediation effect of stress between the experience of discrimination and life satisfaction among North Korean refugees who resettled in South Korea. The findings of the current study provide empirical evidence for the need of social interventions to mitigate adverse effects of stress on North Korean refugees who are subject to social discrimination on a daily basis. In this study, we included 500 subjects among 2,138 North Korean refugees who took refuge in South Korea in 2007. The interview started from April 6th 2009 and finished on May 25th 2009. We conducted moderator effect analysis with Path analysis was conducted because we confirm the experience of discrimination was affected by life satisfaction and stress can affected life satisfaction as a moderator. The experience of discrimination significantly affects stress and stress significantly affects life satisfaction. However, the experience of discrimination was not directly related to life satisfaction. The more stress the study respondents experienced, the lower the life satisfaction they reported. The present finding suggests that the effects of discriminating experiences on the life satisfaction of North Korean refugees in South Korea were mediated by their own perceived stress.

Influence of Cooling Hole Geometry and Material Conductivity on the Thermal Response of Cooled Silicon Nitride Plate

NASA Technical Reports Server (NTRS)

Abdul-Aziz, Ali; Bhatt, Ramakrishna T.; Girgis, Morris

2002-01-01

To complement the effectiveness of ceramic materials and the applicability to turbine engine applications, a parametric study using the finite element method was carried out. This study conducted thorough analyses of a thermal-barrier-coated silicon nitride (Si3N4) plate specimen with cooling channels, where its thermal conductivity was verified in an attempt to minimize the thermal stresses and reach an optimal rate of stress. The thermal stress profile was generated for specimens with circular and square cooling channels. Lower stresses were reported for a higher magnitude of thermal conductivity and in particular for the circular cooling channel arrangement. Contour plots for the stresses and the temperature are presented and discussed.

Mental well-being mediates the relationship between perceived stress and perceived health.

PubMed

Teh, Hui Chian; Archer, Josephine A; Chang, Weining; Chen, S H Annabel

2015-02-01

The association between stress and health has been well researched in the past; however, comparatively few mediators have been tested to understand the underlying mechanism. With increasing awareness on mental well-being, this study evaluated the relationship between perceived stress and perceived health and examined mental well-being as a mediator. Two-hundred undergraduates aged 21 to 26 years completed the English Perceived Stress Scale, Health Status Questionnaire and Asian Mental Well-Being Scale that assess perceived stress, perceived health and mental well-being, respectively. Factor analysis and structural equation modelling on the Perceived Stress Scale replicated the reported two-factor structure after excluding an insignificant item. Linear multiple regression analyses indicated that perceived stress was negatively associated with perceived health. Results showed that mental well-being partially mediated the relationship between perceived stress and perceived health, although it is acknowledged that this association could be bidirectional. Findings from the present study suggest that future research could focus on reducing stress and improving mental well-being to alleviate the effect of stress on health. © 2013 John Wiley & Sons, Ltd.

The effects of social stress and cortisol responses on the preconscious selective attention to social threat.

PubMed

Roelofs, Karin; Bakvis, Patricia; Hermans, Erno J; van Pelt, Johannes; van Honk, Jack

2007-04-01

The purpose of the present study was to investigate the effects of social stress and stress-induced cortisol on the preconscious selective attention to social threat. Twenty healthy participants were administered a masked emotional Stroop task (comparing color-naming latencies for angry, neutral and happy faces) in conditions of rest and social stress. Stress was induced by means of the Trier social stress test. Based on the stress-induced increase in cortisol levels, participants were allocated post hoc (median-split) to a high and low responders group. In contrast to low responders, high responders showed a negative or avoidant attentional bias to threat (i.e. shorter latencies for angry than neutral faces) in the rest condition. Most importantly, although low responders became avoidant, the high responders became vigilant to the angry faces after stress induction. There were no such effects for happy faces. Our findings are in line with previous studies in both animals and humans, that associate high glucocorticoid stress-responsiveness with diminished avoidance and prolonged freezing reactions during stress.

Concurrent Drought Stress and Vascular Pathogen Infection Induce Common and Distinct Transcriptomic Responses in Chickpea

PubMed Central

Sinha, Ranjita; Gupta, Aarti; Senthil-Kumar, Muthappa

2017-01-01

Chickpea (Cicer arietinum); the second largest legume grown worldwide is prone to drought and various pathogen infections. These drought and pathogen stresses often occur concurrently in the field conditions. However, the molecular events in response to that are largely unknown. The present study examines the transcriptome dynamics in chickpea plants exposed to a combination of water-deficit stress and Ralstonia solanacearum infection. R. solanacearum is a potential wilt disease causing pathogen in chickpea. Drought stressed chickpea plants were infected with this pathogen and the plants were allowed to experience progressive drought with 2 and 4 days of R. solanacearum infection called short duration stress (SD stresses) and long duration stress (LD stresses), respectively. Our study showed that R. solanacearum multiplication decreased under SD-combined stress compared to SD-pathogen but there was no significant change in LD-combined stress compared to LD-pathogen. The microarray analysis during these conditions showed that 821 and 1039 differentially expressed genes (DEGs) were unique to SD- and LD-combined stresses, respectively, when compared with individual stress conditions. Three and fifteen genes were common among all the SD-stress treatments and LD-stress treatments, respectively. Genes involved in secondary cell wall biosynthesis, alkaloid biosynthesis, defense related proteins, and osmo-protectants were up-regulated during combined stress. The expression of genes involved in lignin and cellulose biosynthesis were specifically up-regulated in SD-combined, LD-combined, and LD-pathogen stress. A close transcriptomic association of LD-pathogen stress with SD-combined stress was observed in this study which indicates that R. solanacearum infection also exerts drought stress along with pathogen stress thus mimics combined stress effect. Furthermore the expression profiling of candidate genes using real-time quantitative PCR validated the microarray data. The study showed that down-regulation of defense-related genes during LD-combined stress resulted in an increased bacterial multiplication as compared to SD-combined stress. Overall, our study highlights a sub-set of DEGs uniquely expressed in response to combined stress, which serve as potential candidates for further functional characterization to delineate the molecular response of the plant to concurrent drought-pathogen stress. PMID:28382041

The recent (upper Miocene to Quaternary) and present tectonic stress distributions in the Iberian Peninsula

NASA Astrophysics Data System (ADS)

Herraiz, M.; de Vicente, G.; Lindo-Ñaupari, R.; Giner, J.; Simón, J. L.; GonzáLez-Casado, J. M.; Vadillo, O.; RodríGuez-Pascua, M. A.; CicuéNdez, J. I.; Casas, A.; CabañAs, L.; Rincón, P.; CortéS, A. L.; RamíRez, M.; Lucini, M.

2000-08-01

A general synthesis of the recent and present stress situation and evolution in the Iberian Peninsula was obtained from microstructural and seismological analysis. The stress evolution was deduced from (1) fault population analysis (FPA) from 409 sites distributed throughout the Iberian Peninsula, (2) paleostress indicators given by 324 stations taken from the bibliography, and (3) seismic data corresponding to 161 focal mechanisms evenly spread in the studied region. The application of FPA together with the determination of stress tensors and focal mechanisms for the whole Iberian microplate has provided two main results: (1) the Iberian Peninsula is undergoing a NW-SE oriented compression, except for the northeastern part (Pyrenees, Ebro Basin, and Iberian Chain), where it is N-S to NE-SW, and the Gulf of Cádiz, where it seems to be E-W, and (2) the main trends of the stress field have remained almost constant since the upper Miocene. The analysis performed by zones suggests the presence of local heterogeneities in the stress field.

[Brief Scale of Vocational Stress (BSVS)].

PubMed

Dudek, Bohdan; Hauk, Mateusz

2010-01-01

Stress at work is one of the basic notions in applied psychology. There are many approaches to vocational stress presented in the scientific literature and in a number of articles. There is also a variety of methods dedicated to stress assessment. One of the interesting examples is "The Stress in General Scale" developed by Stanton and his coworkers. This questionnaire consists of two subscales named: Pressure and Threat. The operationalisation of the stress at work phenomenon proposed by the authors seems to be very interesting (it allows for quick and easy diagnosis of the problem). That is why, we have decided to prepare the Polish adaptation of this questionnaire. The paper presents individual stages of the adaptation study, which has resulted in the construction of a 26-item questionnaire of the five-factor structure (factor I--Pressure, factor II--Attractiveness, factor III--Risk, factor IV--Liking, factor V--Calm), and the preliminary psychometric properties seem to be satisfactory (e.g. Cronbach alpha = 0.86).

A longitudinal examination of stress generation in depressive and anxiety disorders.

PubMed

Uliaszek, Amanda A; Zinbarg, Richard E; Mineka, Susan; Craske, Michelle G; Griffith, James W; Sutton, Jonathan M; Epstein, Alyssa; Hammen, Constance

2012-02-01

The current study compared two competing theories of the stress generation model of depression (stress causation vs. stress continuation) using interview-based measures of episodic life stress, as well as interpersonal and noninterpersonal chronic life stress. We also expanded on past research by examining anxiety disorders as well as depressive disorders. In addition, we examined the role of neuroticism and extraversion in these relationships. Participants were 627 adolescents enrolled in a two-site, longitudinal study of risk factors for depressive and anxiety disorders. Baseline and follow-up assessments were approximately one year apart. Results supported the stress causation theory for episodic stress generation for anxiety disorders, with neuroticism partially accounting for this relationship. The stress causation theory was also supported for depression, but only for more moderate to severe stressors; neuroticism partially accounted for this relationship as well. Finally, we found evidence for interpersonal and noninterpersonal chronic life stress continuation in both depressive and anxiety disorders. The present findings have implications regarding the specificity of the stress generation model to depressive disorders, as well as variables involved in the stress generation process. PsycINFO Database Record (c) 2012 APA, all rights reserved.

Overdenture retaining bar stress distribution: a finite-element analysis.

PubMed

Caetano, Conrado Reinoldes; Mesquita, Marcelo Ferraz; Consani, Rafael Leonardo Xediek; Correr-Sobrinho, Lourenço; Dos Santos, Mateus Bertolini Fernandes

2015-05-01

Evaluate the stress distribution on the peri-implant bone tissue and prosthetic components of bar-clip retaining systems for overdentures presenting different implant inclinations, vertical misfit and framework material. Three-dimensional models of a jaw and an overdenture retained by two implants and a bar-clip attachment were modeled using specific software (SolidWorks 2010). The studied variables were: latero-lateral inclination of one implant (-10°, -5°, 0°, +5°, +10°); vertical misfit on the other implant (50, 100, 200 µm); and framework material (Au type IV, Ag-Pd, Ti cp, Co-Cr). Solid models were imported into mechanical simulation software (ANSYS Workbench 11). All nodes on the bone's external surface were constrained and a displacement was applied to simulate the settling of the framework on the ill-fitted component. Von Mises stress for the prosthetic components and maximum principal stress to the bone tissue were evaluated. The +10° inclination presented the worst biomechanical behavior, promoting the highest stress values on the bar framework and peri-implant bone tissue. The -5° group presented the lowest stress values on the prosthetic components and the lowest stress value on peri-implant bone tissue was observed in -10°. Increased vertical misfit caused an increase on the stress values in all evaluated structures. Stiffer framework materials caused a considerable stress increase in the framework itself, prosthetic screw of the fitted component and peri-implant bone tissue. Inclination of one implant associated with vertical misfit caused a relevant effect on the stress distribution in bar-clip retained overdentures. Different framework materials promoted increased levels of stress in all the evaluated structures.

Day and night heat stress trigger different transcriptomic responses in green and ripening grapevine (vitis vinifera) fruit

PubMed Central

2014-01-01

Background Global climate change will noticeably affect plant vegetative and reproductive development. The recent increase in temperatures has already impacted yields and composition of berries in many grapevine-growing regions. Physiological processes underlying temperature response and tolerance of the grapevine fruit have not been extensively investigated. To date, all studies investigating the molecular regulation of fleshly fruit response to abiotic stress were only conducted during the day, overlooking possible critical night-specific variations. The present study explores the night and day transcriptomic response of grapevine fruit to heat stress at several developmental stages. Short heat stresses (2 h) were applied at day and night to vines bearing clusters sequentially ordered according to the developmental stages along their vertical axes. The recently proposed microvine model (DRCF-Dwarf Rapid Cycling and Continuous Flowering) was grown in climatic chambers in order to circumvent common constraints and biases inevitable in field experiments with perennial macrovines. Post-véraison berry heterogeneity within clusters was avoided by constituting homogenous batches following organic acids and sugars measurements of individual berries. A whole genome transcriptomic approach was subsequently conducted using NimbleGen 090818 Vitis 12X (30 K) microarrays. Results Present work reveals significant differences in heat stress responsive pathways according to day or night treatment, in particular regarding genes associated with acidity and phenylpropanoid metabolism. Precise distinction of ripening stages led to stage-specific detection of malic acid and anthocyanin-related transcripts modulated by heat stress. Important changes in cell wall modification related processes as well as indications for heat-induced delay of ripening and sugar accumulation were observed at véraison, an effect that was reversed at later stages. Conclusions This first day - night study on heat stress adaption of the grapevine berry shows that the transcriptome of fleshy fruits is differentially affected by abiotic stress at night. The present results emphasize the necessity of including different developmental stages and especially several daytime points in transcriptomic studies. PMID:24774299

Sex differences in stress regulation of arousal and cognition.

PubMed

Bangasser, Debra A; Eck, Samantha R; Telenson, Alexander M; Salvatore, Madeleine

2018-04-01

There are sex differences in the prevalence and presentation of many psychiatric disorders. For example, posttraumatic stress disorder (PTSD) and major depression are more common in women than men, and women with these disorders present with more hyperarousal symptoms than men. In contrast, attention deficit hyperactivity disorder (ADHD) and schizophrenia are more common in men than women, and men with these disorders have increased cognitive deficits compared to women. A shared feature of the aforementioned psychiatric disorders is the contribution of stressful events to their onset and/or severity. Here we propose that sex differences in stress responses bias females towards hyperarousal and males towards cognitive deficits. Evidence from clinical and preclinical studies is detailed. We also describe underlying neurobiological mechanisms. For example, sex differences in stress receptor signaling and trafficking in the locus coeruleus-arousal center are detailed. In learning circuits, evidence for sex differences in dendritic morphology is provided. Finally, we describe how evaluating sex-specific mechanisms for responding to stress in female and male rodents can lead to better treatments for stress-related psychiatric disorders. Copyright © 2017 Elsevier Inc. All rights reserved.

The Promoter of AtUSP Is Co-regulated by Phytohormones and Abiotic Stresses in Arabidopsis thaliana.

PubMed

Bhuria, Monika; Goel, Parul; Kumar, Sanjay; Singh, Anil K

2016-01-01

Universal stress proteins (USPs) are known to be expressed in response to various abiotic stresses in a wide variety of organisms, such as bacteria, archaebacteria, protists, algae, fungi, plants, and animals. However, in plants, biological function of most of the USPs still remains obscure. In the present study, Arabidopsis USP gene ( AtUSP ) showed induction in response to abscisic acid (ABA) and various abiotic stresses viz . heat, dehydration, salt, osmotic, and cold stresses. Additionally, in silico analysis of AtUSP promoter identified several cis -elements responsive to phytohormones and abiotic stresses such as ABRE, ERE, DRE, and HSE, etc. To functionally validate the AtUSP promoter, the 1115 bp region of promoter was characterized under phytohormone and abiotic stress treatments. Deletion analysis of promoter was carried out by cloning the full length promoter (D0) and its three 5' deletion derivatives, D1 (964 bp), D2 (660 bp), and D3 (503 bp) upstream of the β-glucuronidase (GUS) reporter gene, which were then stably transformed in Arabidopsis plants. The AtUSP promoter (D0) showed minimal activity under non-stress conditions which was enhanced in response to phytohormone treatments (ABA and ACC) and abiotic stresses such as dehydration, heat, cold, salt, and osmotic stresses. The seedlings harboring D1 and D2 deletion fragments showed constitutive GUS expression even under control condition with increased activity almost under all the treatments. However, D3 seedlings exhibited complete loss of activity under control condition with induction under ACC treatment, dehydration, heat, oxidative, salt, and osmotic stresses. Thus, present study clearly showed that AtUSP promoter is highly inducible by phytohormones and multiple abiotic stresses and it can be exploited as stress inducible promoter to generate multi-stress tolerant crops with minimal effects on their other important traits.

Abuse history and premenstrual symptomatology: assessing the mediating role of perceived stress.

PubMed

Lustyk, M Kathleen B; Widman, Laura; Becker, Linda de Laveaga

2007-01-01

The present study assessed the interrelationships among abuse history (Abuse), perceived stress (Stress), and premenstrual symptom severity reports (PMSR) among female college students (N = 91, 18-25 years old), and determined if Stress mediated the relationship between Abuse and PMSR. Abuse history was noted by 44% of women in this sample, including sexual (25%), physical (11%), or both sexual and physical (8%) abuse. Importantly, results showed significant positive relationships between Abuse, Stress, and PMSR, suggesting Abuse affects psychological and physical aspects of women's health. Overall, women rated PMSR affect symptoms highest, and abused women rated pain and water retention higher than non-abused women. Stress did not fully mediate the relationship between Abuse and PMSR in this study, but accounted for 24% of the variance between these variables. The health implications of these findings are discussed.

[Stress and Burnout Risk in Nursery School Teachers: Results from a Survey].

PubMed

Jungbauer, J; Ehlen, S

2015-06-01

This article presents results from a study of 834 nursery school teachers in Germany, investigating working conditions, stress, and stress-related health problems. In order to evaluate the extent of mental and psychosomatic troubles, as well as the risk of burnout, we used the standardised questionnaire "Burnout Screening Scales" (BOSS I). Data analysis yielded a high percentage of nursery school teachers who reported a remarkably high stress level; nearly 20% can be considered as a high-risk group for burnout. Poor staff conditions in many nurseries turned out to be the crucial stress source, along with large groups, insufficient teacher-child ratio, time pressure and multitasking. In the concluding discussion of the study results, we consider possible measures to reduce stress and to improve working conditions for nursery school teachers. © Georg Thieme Verlag KG Stuttgart · New York.

Occupational stress, mental health and coping among information technology professionals.

PubMed

Rao, Jakkula V; Chandraiah, K

2012-01-01

Experience of occupational stress is inevitably involved in the execution of any type of work. Stress has an adaptive value. It motivates the individual to attend to the task and get rid of the tension or demand the unattended task produced. The study was planned to investigate the differences between executives and shop floor workers on occupational stress, mental health, job satisfaction and coping. A random sample of 200 executives and shop floor employees collected from Nuclear Fuel Complex of Hyderabad City. A well developed sub-scales of Occupational Stress indicator like Mental Health, and Coping behavior were used in the present study. The shop floor workers experiencing more job stress and lower mental health. But these two groups did not differ in their coping behaviour. The executives are better with work home balance.

[Tool for measuring occupational stress: a nurses' stress inventory].

PubMed

Stacciarini, J M; Tróccoli, B T

2000-12-01

We present an exploratory study aiming at constructing an inventory to measure occupational stress in nurses ("Inventário de Estresse em Enfermeiros"--IEE). A set of items was initially constructed from previously defined categories based on interviews with nurses and then improved through semantic analysis by referees and a pilot-test with nursing students. A sample of 461 nurses--workers from the public services of the Federal District--who answered the IEE was used in the study. Factorial analysis indicated the presence of a second-order global factor and three first-order factors: Interpersonal Relationships, Stressful Career Roles and Intrinsic Job Factors.

Finite element analysis of the influence of elastic anisotropy on stress intensification at stress corrosion cracking initiation sites in fcc alloys

NASA Astrophysics Data System (ADS)

Meric de Bellefon, G.; van Duysen, J. C.

2018-05-01

A recent finite-element method (FEM)-based study from the present authors quantified the effect of elastic anisotropy of grains on stress intensification at potential intergranular stress corrosion cracking (IGSCC) initiation sites in austenitic stainless steels. In particular, it showed that the auxetic behavior of grains (negative Poisson's ratio) in some directions plays a very important role in IGSCC initiation, since it can induce local stress intensification factors of about 1.6. A similar effect is expected for other fcc alloys such as Ni-based alloys. The present article confirms those results and paves the way to the definition of an IGSCC susceptibility index by identifying grain configurations that are the most favorable for crack initiation. The index will rely on the probability to get those configurations on surface of specimens.

Effect of high-fat intake on motor activity, homovanillic acid and 5-hydroxyindoleacetic acid levels in striatum and cortex of rats exposed to stress.

PubMed

Kirac, Deniz; Ozden, Inci; Yildirim, Alper; Genç, Ece

2009-04-01

The aim of the present study was to investigate whether high fat consumption changes the effects of stress on both motor activity performance, striatal and cortical dopamine and serotonin metabolites in rats. The animals were fed either with high fat or standard diet for 4 weeks. Restraint stress lasting for 15 min at +4 degrees C was applied daily to stress-exposed groups. Motor activity performance was measured weekly by using motor activity monitoring systems. At the end of the study, homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) levels of the striatum and cerebral cortex were measured by HPLCEC. It was observed that restraint stress increased locomotor activity and high-fat diet prevented this effect. Stress and high-fat intake had an additive decreasing effect on striatal HVA levels. 5-HIAA levels, on the other hand, were lower in both high fat and high fat + stress groups compared to the stress group. These results suggest that high-fat intake differentially affected the stress response on striatal dopaminergic and serotonergic neurons in rat brain regions studied and this may be related to the effects observed in motor activity performance.

Effects of the Cognitive-Behavioral Therapy for Stress Management on Executive Function Components.

PubMed

Santos-Ruiz, Ana; Robles-Ortega, Humbelina; Pérez-García, Miguel; Peralta-Ramírez, María Isabel

2017-02-13

This study aims to determine whether it is possible to modify executive function in stressed individuals by means of cognitive-behavioral therapy for stress management. Thirty-one people with high levels of perceived stress were recruited into the study (treatment group = 18; wait-list group = 13). The treatment group received 14 weeks of stress management program. Psychological and executive function variables were evaluated in both groups pre and post-intervention. The treatment group showed improved psychological variables of perceived stress (t = 5.492; p = .001), vulnerability to stress (t = 4.061; p = .001) and superstitious thinking (t = 2.961; p = .009). Likewise, the results showed statistically significant differences in personality variables related to executive function, positive urgency (t = 3.585; p = .002) and sensitivity to reward (t = -2.201; p = .042), which improved after the therapy. These variables showed a moderate to high effect size (oscillates between 1.30 for perceived stress and .566 for sensitivity to reward). The cognitive-behavioral therapy for stress management may be an appropriate strategy for improving personality construct components related to executive function, however effects of the therapy are not showed on performance on the tests of executive function applied, as presented studies previous.

Factor Structure of the Acute Stress Disorder Scale in a Sample of Hurricane Katrina Evacuees

ERIC Educational Resources Information Center

Edmondson, Donald; Mills, Mary Alice; Park, Crystal L.

2010-01-01

Acute stress disorder (ASD) is a poorly understood and controversial diagnosis (A. G. Harvey & R. A. Bryant, 2002). The present study used confirmatory factor analysis (CFA) to test the factor structure of the most widely used self-report measure of ASD, the Acute Stress Disorder Scale (R. A. Bryant, M. L. Moulds, & R. M. Guthrie, 2000),…

Examining Infants' Cortisol Responses to Laboratory Tasks among Children Varying in Attachment Disorganization: Stress Reactivity or Return to Baseline?

ERIC Educational Resources Information Center

Bernard, Kristin; Dozier, Mary

2010-01-01

Cortisol is a hormone involved in mounting a stress response in humans. The evidence of stress reactivity among young children has been mixed, however. In the present study, the order of two laboratory tasks (i.e., Strange Situation and play) was counterbalanced, and home saliva samples were obtained. Saliva samples were also collected upon the…

The Role of Neuroticism and Perceived School-Related Stress in Somatic Symptoms among Students in Norwegian Junior High Schools

ERIC Educational Resources Information Center

Murberg, Terje A.; Bru, Edvin

2007-01-01

The present study investigated the role of neuroticism and perceived school-related stress in somatic symptoms among a sample of 327 (167 females and 160 males) students in two Norwegian junior high schools. The results suggest that the role of neuroticism on somatic symptoms may be overestimated, and that the role of stress may be underestimated…

Parenting Stress and Child Behavior Problems among Clinic-Referred Youth: Cross-Cultural Differences across the US and Korea

ERIC Educational Resources Information Center

Chung, Kyong-Mee; Ebesutani, Chad; Bang, Hye Min; Kim, Joohee; Chorpita, Bruce F.; Weisz, John R.; Suh, Dongsoo; Byun, Heejung

2013-01-01

Due to increased multiculturalism in the US and abroad, there is a need for increased understanding of the different ways in which parenting stress is related to child problems across cultures. In the present study, we investigated (a) differences in reported parenting stress and childhood problem behaviors across a Korean (n = 71) and US (n = 71)…

The Influence of Perceived Stress, Loneliness, and Learning Burnout on University Students' Educational Experience

ERIC Educational Resources Information Center

Stoliker, Bryce E.; Lafreniere, Kathryn D.

2015-01-01

University is a pivotal period in a young adult's life; however, for some, university may be a recipe for disaster due to the stress and pressures that come along with university education. The purpose of the present study was to examine students' feelings of stress, loneliness, and levels of learning burnout in order to determine if these factors…

A BDNF Sensitive Mechanism Is Involved in the Fear Memory Resulting from the Interaction between Stress and the Retrieval of an Established Trace

ERIC Educational Resources Information Center

Giachero, Marcelo; Bustos, Silvia G.; Calfa, Gaston; Molina, Victor A.

2013-01-01

The present study investigates the fear memory resulting from the interaction of a stressful experience and the retrieval of an established fear memory trace. Such a combination enhanced both fear expression and fear retention in adult Wistar rats. Likewise, midazolam intra-basolateral amygdala (BLA) infusion prior to stress attenuated the…

OsACA6, a P-type 2B Ca(2+) ATPase functions in cadmium stress tolerance in tobacco by reducing the oxidative stress load.

PubMed

Shukla, Devesh; Huda, Kazi Md Kamrul; Banu, Mst Sufara Akhter; Gill, Sarvajeet Singh; Gill, Sarvjeet Singh; Tuteja, Renu; Tuteja, Narendra

2014-10-01

The present study demonstrates the first direct evidence of the novel role of OsACA6 in providing Cd (2+) stress tolerance in transgenic tobacco by maintaining cellular ion homeostasis and modulating ROS-scavenging pathway. Cadmium, a non-essential toxic heavy metal, interferes with the plant growth and development. It reaches the leaves through xylem and may become part of the food chain, thus causing detrimental effects to human health. Therefore, there is an urgent need to develop strategies for engineering plants for Cd(2+) tolerance and less accumulation. The members of P-type ATPases family transport metal ions including Cd(2+), and thus play important role an ion homeostasis. The present study elucidates the role of P-type 2B Ca(2+) ATPase (OsACA6) in Cd(2+) stress tolerance. The transcript levels of OsACA6 were up-regulated upon Cd(2+), Zn(2+) and Mn(2+) exposure. Transgenic tobacco expressing OsACA6 showed tolerance towards Cd(2+) stress as demonstrated by several physiological indices including root length, biomass, chlorophyll, malondialdehyde and hydrogen peroxide content. The roots of the transgenic lines accumulated more Cd(2+) as compared to shoot. Further, confocal laser scanning microscopy showed that Cd(2+) exposure altered Ca(2+) uptake in OsACA6 transgenic plants. OsACA6 expression in tobacco also protected the transgenic plants from oxidative stress by enhancing the activity of enzymatic (SOD, CAT, APX, GR) and non-enzymatic (GSH and AsA) antioxidant machinery. Transgenic lines also tolerated Zn(2+) and Mn(2+) stress; however, tolerance for these ions was not as significant as observed for Cd(2+) exposure. Thus, overexpression of OsACA6 confers Cd(2+) stress tolerance in transgenic lines by maintaining cellular ion homeostasis and modulating reactive oxygen species (ROS)-scavenging pathway. The results of the present study will help to develop strategies for engineering Cd(2+) stress tolerance in economically important crop plants.

The Relationship between Personality, Sense of Efficacy, and Stress in Korean Teachers.

PubMed

Park, Subin; Song, Yul-Mai; Ko, Guy-Nueo; Jhung, Kyungun; Ha, Kyooseob; Lee, Young-Ryeol; Kim, Yeni

2016-09-01

Several studies have linked teachers' personality characteristics and sense of efficacy to stress. However, investigating the relationship between these three constructs in this context was limited. This study aims to investigate the relationship between personality, sense of efficacy and perceived stress among Korean teachers. A total of 137 teachers working in elementary, middle, and high schools located in Seoul, South Korea were recruited for the study. The participants were administered Temperament and Character Inventory, Teacher's Sense of Efficacy Scale (TSES), and Perceived Stress Scale. The TSES was negatively correlated with harm avoidance and positively correlated with persistence, self-directedness, cooperativeness, and self-transcendence. Perceived stress was positively correlated with harm avoidance and negatively correlated with persistence and self-directedness. The path analysis showed that harm avoidance directly predicted perceived stress (β=0.37, 95% CI=0.21-0.53, p=0.002), and self-directedness and persistence predicted one's sense of efficacy (β=0.18, 95% CI=0.01-0.39 and β=0.31, 95% CI=0.10-0.47), which predicted perceived stress (β=-0.21, 95% CI=-0.39 to -0.02). The results of the present study indicate that harm avoidance might be associated with stress-proneness, while persistence, self-directedness, and sense of efficacy might act as protective resources against stress in Korean teachers.

Ambulatory assessment of skin conductivity during first thesis presentation: lower self-confidence predicts prolonged stress response.

PubMed

Elfering, Achim; Grebner, Simone

2011-06-01

In this field study self-confidence was tested to predict the course of galvanic electrodermal stress response prior, during and after public speaking. Ten graduate students initially rated their self-confidence and afterwards presented their thesis proposals orally in a 10-min presentation to their supervisor and peers. Galvanic skin response level was measured throughout and analysed for 10 min prior to, during, and 10 min after the presentation. Two major galvanic electrodermal stress response types were observed. Five students showed a 'healthy response', i.e. an anticipatory increase in electrodermal conductance, followed by a decrease after termination of the presentation. The other five students showed a steady increase of skin conductance during and after their presentation ('prolonged response'). In line with the allostatic load model the 'prolonged response' group reported significantly lower self-confidence before presentation than the 'healthy response' group (p < 0.01). Self-confidence is a resource in novices facing an unfamiliar stressor.

Accelerated stress testing of terrestrial solar cells

NASA Technical Reports Server (NTRS)

Prince, J. L.; Lathrop, J. W.

1979-01-01

A program to investigate the reliability characteristics of unencapsulated low-cost terrestrial solar cells using accelerated stress testing is described. Reliability (or parametric degradation) factors appropriate to the cell technologies and use conditions were studied and a series of accelerated stress tests was synthesized. An electrical measurement procedure and a data analysis and management system was derived, and stress test fixturing and material flow procedures were set up after consideration was given to the number of cells to be stress tested and measured and the nature of the information to be obtained from the process. Selected results and conclusions are presented.

Interlaminar stress singularities at a straight free edge in composite laminates

NASA Technical Reports Server (NTRS)

Raju, I. S.; Crews, J. H., Jr.

1981-01-01

A quasi-three-dimensional finite-element analysis was used to analyze the edge-stress problem in four-ply, composite laminates. The seven laminates that were considered belong to the laminate family where the outer ply angle is between 0 and 90 deg. Systematic convergence studies were made to explore the existence of stress singularities near the free edge. The present analysis appears to confirm the existence of stress singularities at the intersection of the interface and the free edge. The power of the stress singularity was the same for all seven laminates considered.

Phenotypic heterogeneity in a bacteriophage population only appears as stress-induced mutagenesis.

PubMed

Yosef, Ido; Edgar, Rotem; Qimron, Udi

2016-11-01

Stress-induced mutagenesis has been studied in cancer cells, yeast, bacteria, and archaea, but not in viruses. In a recent publication, we present a bacteriophage model showing an apparent stress-induced mutagenesis. We show that the stress does not drive the mutagenesis, but only selects the fittest mutants. The mechanism underlying the observed phenomenon is a phenotypic heterogeneity that resembles persistence of the viral population. The new findings, the background for the ongoing debate on stress-induced mutagenesis, and the phenotypic heterogeneity underlying a novel phage infection strategy are discussed in this short manuscript.

An Experimental Evaluation of Adaptogenic Potential of Standardized Epipremnum Aureum Leaf Extract.

PubMed

Das, Sreemoy Kanti; Sengupta, Pinaki; Mustapha, Mohd Shahimi; Sarker, Md Moklesur Rahman

2017-01-01

Stress is a normal part of everyday life but chronic stress can lead to a variety of stress-related illnesses including hypertension, anxiety, and depression. In the present investigation, standardized leaf extract of Epipremnumaureum was evaluated for its anti-stress potential. For the evaluation of anti-stress activity, groups of mice ( n = 6) were subjected to forced swim stress and anoxic stress tolerance test in mice 1h after daily treatment of E.aureumextract . Diazepam (5 mg/kg) was taken as a reference standard. Urinary vanillylmandelic acid (VMA) and ascorbic acid were selected as noninvasive biomarkers to assess the anti-stress activity and plasma cortisol, blood ascorbic acid, and weight of adrenal were measured. The 24 h urinary excretion of VMA and ascorbic acid were determined by spectrophotometric methods in all groups under normal and stressed conditions. The hematological parameters (neutrophils, lymphocytes, and eosinophils) were also determined. Administration of E.aureumat doses of 400 and 600 mg/kg wasfound to be effective in inhibiting the stress induced urinary biochemical changes in a dose-dependent manner. Treatment with E. aureum extract prevents the rise in blood ascorbic acid and plasma cortisol. Moreover, the extract prevented the increase in weight of adrenal gland also significantly increased the anoxia stress tolerance time. Dose-dependent significant reduction in white blood cell count was observed in anoxic stress tolerance test as compared to stressed group. Hence, the present study provides scientific support for the positiveadaptogenic effect of E. aureum extract.

Climate change projections of heat stress in Europe: From meteorological variables to impacts on productivity

NASA Astrophysics Data System (ADS)

Casanueva, Ana; Kotlarski, Sven; Liniger, Mark A.

2017-04-01

Future climate change is likely to have important impacts in many socio-economic sectors. In particular, higher summer temperatures or more prolonged heat waves may be responsible for health problems and productivity losses related to heat stress, especially affecting people exposed to such situations (e.g. working under outside settings or in non-acclimatized workplaces). Heat stress on the body under work load and consequently their productivity loss can be described through heat stress indices that are based on multiple meteorological parameters such as temperature, humidity, wind and radiation. Exploring the changes of these variables under a warmer climate is of prime importance for the Impacts, Adaptation and Vulnerability communities. In particular, the H2020 project HEAT-SHIELD aims at analyzing the impact of climate change on heat stress in strategic industries in Europe (manufacturing, construction, transportation, tourism and agriculture) within an inter-sectoral framework (climate scientists, biometeorologists, physiologists and stakeholders). In the present work we explore present and future heat stress over Europe using an ensemble of the state-of-the-art RCMs from the EURO-CORDEX initiative. Since RCMs cannot be directly used in impact studies due to their partly substantial biases, a standard bias correction method (empirical quantile mapping) is applied to correct the individual variables that are then used to derive heat stress indices. The objectives of this study are twofold, 1) to test the ability of the separately bias corrected variables to reproduce the main characteristics of heat stress indices in present climate conditions and 2) to explore climate change projections of heat stress indices. We use the wet bulb globe temperature (WBGT) as primary heat stress index, considering two different versions for indoor (or in the shade, based on temperature and humidity conditions) and outdoor settings (including also wind and radiation). The WBGT is the most widely used heat stress index for working people and can be easily interpreted by means of ISO standards. Within the HEAT-SHIELD project, climate change projections of the WBGT will be used to assess the impact of climate change on workers' health and productivity.

A pharmacological investigation of Hippophae salicifolia (HS) and Hippophae rhamnoides turkestanica (HRT) against multiple stress (C-H-R): an experimental study using rat model.

PubMed

Rathor, Richa; Sharma, Priyanka; Suryakumar, Geetha; Ganju, Lilly

2015-09-01

Hippophae salicifolia (HS) and Hippophae rhamnoides turkestanica (HRT) are abundantly found species of Hippophae in Himalayan region of India. As these plants thrive under extreme climatic conditions, it is suspected that these plants must have a unique adaptogenic property against high-altitude stress. To keeping these views in our mind, the present study was planned to evaluate the mechanism of action of aqueous extract of HS and aqueous extract of HRT against multiple stress [cold-hypoxia-restraint (C-H-R)] for their adaptogenic activity. The present study reported the adaptogenic activity of HS in facilitating tolerance to multiple stress, CHR in rats. Pre-treatment with aqueous extract of HS significantly attenuated reactive oxygen species (ROS) production, protein oxidation, and lipid peroxidation and also showed role in maintaining antioxidant status as similar to control rats. Since protein oxidation was decreased by pre-treatment of HS, protein homeostasis was also sustained by regulation of heat shock proteins (HSP70 and HSP60). Interestingly, heme oxygenase-1 (HO-1), Vascular Endothelial Growth Factor (VEGF), and nitric oxide (NO) level was also increased in HS pre-treated rats depicted its adaptogenic activity against multiple stress, CHR. Conclusively, aqueous extract of HS could use an adaptogen for high altitude-associated multiple stress (CHR).

Stress-Induced Depression Is Alleviated by Aerobic Exercise Through Up-Regulation of 5-Hydroxytryptamine 1A Receptors in Rats

PubMed Central

Kim, Tae Woon; Lim, Baek Vin; Baek, Dongjin; Ryu, Dong-Soo; Seo, Jin Hee

2015-01-01

Purpose: Stress is associated with depression, which induces many psychiatric disorders. Serotonin, also known as 5-hydroxy-tryptamine (5-HT), acts as a biochemical messenger and regulator in the brain. It also mediates several important physiological functions. Depression is closely associated with an overactive bladder. In the present study, we investigated the effect of treadmill exercise on stress-induced depression while focusing on the expression of 5-HT 1A (5-H1A) receptors in the dorsal raphe. Methods: Stress was induced by applying a 0.2-mA electric foot shock to rats. Each set of electric foot shocks comprised a 6-second shock duration that was repeated 10 times with a 30-second interval. Three sets of electric foot shocks were applied each day for 7 days. For the confirmation of depressive state, a forced swimming test was performed. To visualize the expression of 5-HT and tryptophan hydroxylase (TPH), immunohistochemistry for 5-HT and TPH in the dorsal raphe was performed. Expression of 5-H1A receptors was determined by western blot analysis. Results: A depressive state was induced by stress, and treadmill exercise alleviated the depression symptoms in the stress-induced rats. Expressions of 5-HT, TPH, and HT 1A in the dorsal raphe were reduced by the induction of stress. Treadmill exercise increased 5-HT, TPH, and HT 1A expressions in the stress-induced rats. Conclusions: Treadmill exercise enhanced 5-HT synthesis through the up-regulation of 5-HT1A receptors, and improved the stress-induced depression. In the present study, treadmill exercise improved depression symptoms by enhancing 5-HT1A receptor expression. The present results suggest that treadmill exercise might be helpful for the alleviation of overactive bladder and improve sexual function. PMID:25833478

Deployment Family Stress: Child Neglect and Maltreatment in U.S. Army Families

DTIC Science & Technology

2009-10-01

in u.s. Army Families." The rationale for the study was based on scientific reports indicating a possible connection between the increase in rates of...greater ease of use in the future. Key Research Accomplishments a. Scientific poster presentations ("Deployment Family Stress: Child Neglect and...Community Resources Questionnaire Appendix D: Example copy of Neglect Poster Presentation 4 Appendix A KEY INFORMANT COMMUNITY RESOURCES QUESTIONNAIRE

[Effects of water stress on red-edge parameters and yield in wheat cropping].

PubMed

He, Ke-Xun; Zaho, Shu-He; Lai, Jian-Bin; Luo, Yun-Xiao; Qin, Zhi-Hao

2013-08-01

The objective of the present paper is to study the influence of water stress on wheat spectrum red edge parameters by using field wheat spectrum data obtained from water stress experiment. Firstly, the authors analyzed the influence of water stress on wheat spectrum reflectance. Then the authors got the wheat red edge position and red edge peak through calculating wheat spectrum first-order differential and analyzed the influence of water stress on wheat red edge parameters. Finally the authors discussed the relationship between red peak and wheat yield. The results showed that the wheat red edge position shows "red shift" at the beginning of the wheat growth period and "blue shift" at the later period of the wheat growth period under the water stress experiment. Also, the red edge peak of the wheat showed that red edge peak increased with the water stress sharpening at the beginning of the wheat growth period, and then the red edge peak reduced with the water stress sharpening. The wheat red edge peak presented positive correlation with the wheat yield before the elongation period, and exhibited negative correlation after that period.

Neuroprotective mechanism of losartan and its interaction with nimesulide against chronic fatigue stress.

PubMed

Kumar, Anil; Singh, Barinder; Mishra, Jitendriya; Sah, Sangeeta Pilkhwal; Pottabathini, Raghavender

2015-12-01

Potential role of angiotensin-II and cyclooxygenase have been suggested in the pathophysiology of chronic fatigue stress. The present study has been designed to evaluate the neuroprotective effect of losartan and its interaction with nimesulide against chronic fatigue stress and related complications in mice. In the present study, male Laca mice (20-30 g) were subjected to running wheel activity test session (RWATS) for 6 min daily for 21 days. Losartan, nimesulide and their combinations were administered daily for 21 days, 45 min before being subjected to RWATS. Various behavioral and biochemical and neuroinflammatory mediators were assessed subsequently. 21 days RWATS treatment significantly decreased number of wheel rotations/6 min indicating fatigue stress like behaviors as compared to naive group. 21 days treatment with losartan (10 and 20 mg/kg, ip), nimesulide (5 and 10 mg/kg, po) and their combinations significantly improved behavior [increased number of wheel rotations, reversal of post-exercise fatigue, locomotor activity, antianxiety-like behavior (number of entries, latency to enter and time spent in mirror chamber), and memory performance (transfer latency in plus-maze performance task)], biochemical parameters (reduced serum corticosterone, brain lipid peroxidation, nitrite concentration, acetylcholinesterase activity, restored reduced glutathione levels and catalase activity) as compared to RWATS control. Besides, TNF-α, CRP levels were significantly attenuated by these drugs and their combinations as compared to control. The present study highlights the role of cyclooxygenase modulation in the neuroprotective effect of losartan against chronic fatigue stress-induced behavioral, biochemical and cellular alterations in mice.

Work-related stress and quality of life among Iranian blue-collar workers with self-reported low back pain.

PubMed

Kabir-Mokamelkhah, Elaheh; Bahrami-Ahmadi, Amir; Aghili, Negar

2016-01-01

Background: Impairment in quality of life and mental health had been reported in the previous studies as the results of musculoskeletal disorders among workers. Mental health has a wide concept and contains different disorders including anxiety, depression or even decreased quality of life, all of which having challengeable impacts on work- related characters such as work productivity and absensism. The present study aimed at evaluating work- related stress and quality of life among Iranian blue-collar workers of Fars ABFA Company with selfreported low back pain. Methods: In the present study, we focused on the low back pain among 451 blue-collar workers and assessed their work- related stress and quality of life status using DASS-21 and short form questionnaire (SF-36), respectively. Independent sample t-test was used to compare the qualitative variables, and chi-square test was utilized for statistical analysis of the qualitative variables. Results: Mean of the total score of quality of life among workers with low back pain was significantly lower than in those workers without low back pain. The mean of work- related stress score was significantly higher in workers with low back pain than in workers without low back pain. The mean quality of life subdomains in patients with low back pain was significantly lower than in workers without low back pain. Conclusion: Findings of the present study revealed that workers with low back pain had lower quality of life score and higher work- related stress score. These findings should be considered in designing preventive programs rather than controlling the pain.

Tissue distribution of HSPA9/mortalin in avian species and its regulation by gender, genotype and heat stress

USDA-ARS?s Scientific Manuscript database

Heat shock 70kDa protein 9 (HSPA9)/mortalin is a multipotent chaperone regulating cellular processes ranging from stress response to energy homeostasis. HSPA9 has been extensively studied in mammals however there is a paucity of information in avian species. The present study aimed to characterize H...

Posttraumatic Stress Disorder among Sri Lankan University Students as a Consequence of Their Exposure to Family Violence

ERIC Educational Resources Information Center

Haj-Yahia, Muhammad M.; Tishby, Orya; de Zoysa, Piyanjali

2009-01-01

The article presents the results of a study on the association between exposure to family violence (i.e., witnessing interparental violence and experiencing parental violence) during childhood and adolescence and adult posttraumatic stress disorder (PTSD). The study was conducted among a self-selected convenience sample of 476 students from Sri…

Students' Coping with Academic and Social Stress in an Inner-City Middle School.

ERIC Educational Resources Information Center

Fahs, Mary Ellen

This report presents the findings of several studies designed to examine students' coping processes in relation to stressful academic and social situations in the school environment. The setting for these studies was an inner-city intermediate school with approximately 423 students in the 1984-85 school year. Over 95 percent of the students were…

Gender and Age Differences in How Children Cope with Daily Stress

ERIC Educational Resources Information Center

Morales Rodriguez, Francisco Manuel; Trianes Torres, Maria Victoria; Miranda Paez, Jesus

2012-01-01

Introduction: The study of coping among students accounts for an interesting subject, as having coping skills guarantees a healthy lifestyle and quality of life. The present study aims to analyze the role played by age and gender on the coping strategies used by Andalusian school students to cope with situations of daily stress. These situations…

Stress and Coping Styles Are Associated with Severe Fatigue in Medical Students

ERIC Educational Resources Information Center

Tanaka, Masaaki; Fukuda, Sanae; Mizuno, Kei; Kuratsune, Hirohiko; Watanabe, Yasuyoshi

2009-01-01

Fatigue is a common complaint among medical students and researchers consider it to be related to poor academic outcomes. The authors' goal in the present study was to determine whether stress and coping strategies were associated with fatigue in medical students. The study group consisted of 73 second-year healthy students attending the Osaka…

Posttraumatic Stress Disorder Symptom Structure in Chinese Adolescents Exposed to a Deadly Earthquake

ERIC Educational Resources Information Center

Wang, Li; Long, Di; Li, Zhongquan; Armour, Cherie

2011-01-01

This present study examined the structure of posttraumatic stress disorder (PTSD) symptoms in a large sample of Chinese adolescents exposed to a deadly earthquake. A total of 2,800 middle school students aged 12 to 18 years participated in the study 6 months after the "Wenchuan Earthquake". Results of confirmatory factor analysis…

Associations between Prolonged Grief Disorder, Depression, Posttraumatic Stress Disorder, and Anxiety in Rwandan Genocide Survivors

ERIC Educational Resources Information Center

Schaal, Susanne; Dusingizemungu, Jean-Pierre; Jacob, Nadja; Neuner, Frank; Elbert, Thomas

2012-01-01

A number of studies have demonstrated that symptoms of prolonged grief disorder (PGD) represent a symptom cluster distinct from bereavement-related depression, anxiety, and posttraumatic stress disorder (PTSD). The aim of the present study was to confirm and extend these findings using the most recent criteria defining PGD. The authors interviewed…

Stress-Neutral Endings in Contemporary British English: An Updated Overview

ERIC Educational Resources Information Center

Trevian, Ives

2007-01-01

The present study is an attempt to account for current changes taking place in the behaviour of what are commonly taken to be stress-neutral endings in contemporary British English. The methodological framework being that of Lionel Guierre, this study aims for comprehensive coverage, via a survey of Guierre's original database (which was initially…

Chemical chaperones reduce ER stress and adipose tissue inflammation in high fat diet-induced mouse model of obesity.

PubMed

Chen, Yaqin; Wu, Zhihong; Zhao, Shuiping; Xiang, Rong

2016-06-08

Obesity, which is characteristic by chronic inflammation, is defined as abnormal or excessive fat accumulation in adipose tissues. Endoplasmic reticulum (ER) stress is increased in adipose tissue of obese state and is known to be strongly associated with chronic inflammation. The aim of this study was to investigate the effect of ER stress on adipokine secretion in obese mice and explore the potential mechanisms. In this study, we found high-fat diet induced-obesity contributed to strengthened ER stress and triggered chronic inflammation in adipose tissue. Chemical chaperones, 4-PBA and TUDCA, modified metabolic disorders and decreased the levels of inflammatory cytokines in obese mice fed a high-fat diet. The alleviation of ER stress is in accordance with the decrease of free cholesterol in adipose tissue. Furthermore chemical chaperones suppress NF-κB activity in adipose tissue of obese mice in vivo. In vitro studies showed IKK/NF-κB may be involved in the signal transduction of adipokine secretion dysfunction induced by ER stress. The present study revealed the possibility that inhibition of ER stress may be a novel drug target for metabolic abnormalities associated with obesity. Further studies are now needed to characterize the initial incentive of sustained ER stress in obese.

True or false? Memory is differentially affected by stress-induced cortisol elevations and sympathetic activity at consolidation and retrieval.

PubMed

Smeets, Tom; Otgaar, Henry; Candel, Ingrid; Wolf, Oliver T

2008-11-01

Adrenal stress hormones released in response to acute stress may yield memory-enhancing effects when released post-learning and impairing effects at memory retrieval, especially for emotional memory material. However, so far these differential effects of stress hormones on the various memory phases for neutral and emotional memory material have not been demonstrated within one experiment. This study investigated whether, in line with their effects on true memory, stress and stress-induced adrenal stress hormones affect the encoding, consolidation, and retrieval of emotional and neutral false memories. Participants (N=90) were exposed to a stressor before encoding, during consolidation, before retrieval, or were not stressed and then were subjected to neutral and emotional versions of the Deese-Roediger-McDermott word list learning paradigm. Twenty-four hours later, recall of presented words (true recall) and non-presented critical lure words (false recall) was assessed. Results show that stress exposure resulted in superior true memory performance in the consolidation stress group and reduced true memory performance in the retrieval stress group compared to the other groups, predominantly for emotional words. These memory-enhancing and memory-impairing effects were strongly related to stress-induced cortisol and sympathetic activity measured via salivary alpha-amylase levels. Neutral and emotional false recall, on the other hand, was neither affected by stress exposure, nor related to cortisol and sympathetic activity following stress. These results demonstrate the importance of stress-induced hormone-related activity in enhancing memory consolidation and in impairing memory retrieval, in particular for emotional memory material.

Experimental study on the bed shear stress under breaking waves

NASA Astrophysics Data System (ADS)

Hao, Si-yu; Xia, Yun-feng; Xu, Hua

2017-06-01

The object of present study is to investigate the bed shear stress on a slope under regular breaking waves by a novel instrument named Micro-Electro-Mechanical System (MEMS) flexible hot-film shear stress sensor. The sensors were calibrated before application, and then a wave flume experiment was conducted to study the bed shear stress for the case of regular waves spilling and plunging on a 1:15 smooth PVC slope. The experiment shows that the sensor is feasible for the measurement of the bed shear stress under breaking waves. For regular incident waves, the bed shear stress is mainly periodic in both outside and inside the breaking point. The fluctuations of the bed shear stress increase significantly after waves breaking due to the turbulence and vortexes generated by breaking waves. For plunging breaker, the extreme value of the mean maximum bed shear stress appears after the plunging point, and the more violent the wave breaks, the more dramatic increase of the maximum bed shear stress will occur. For spilling breaker, the increase of the maximum bed shear stress along the slope is gradual compared with the plunging breaker. At last, an empirical equation about the relationship between the maximum bed shear stress and the surf similarity parameter is given, which can be used to estimate the maximum bed shear stress under breaking waves in practice.

Safety Climate and Occupational Stress According to Occupational Accidents Experience and Employment Type in Shipbuilding Industry of Korea.

PubMed

Kim, Kyung Woo; Park, Sung Jin; Lim, Hae Sun; Cho, Hm Hak

2017-09-01

Safety climate and occupational stress are related with occupational accident. The present study tried to identify the differences in safety climate and occupational stress according to occupational accidents experience and employment type (e.g., direct workers and subcontract workers). In this study, we conducted a survey using safety climate scale and Korean Occupational Stress Scale and classified the participants into four groups: direct workers working for accident-free departments, direct workers working for accident departments, subcontract workers working for accident-free departments, and subcontract workers working for accident departments for 2 years within the same workplace in the shipbuilding industry. The direct workers and subcontract workers showed diverse results in subscales of safety climate and occupational stress. This result is supported by existing studies; however, further study is necessary for more supporting evidence and elaborative methodological approach. The necessity of management for safety climate and psychosocial factor such as occupational stress for both direct workers and subcontract workers as a whole is suggested by this study.

Deriving Requirements for Pervasive Well-Being Technology From Work Stress and Intervention Theory: Framework and Case Study.

PubMed

Koldijk, Saskia; Kraaij, Wessel; Neerincx, Mark A

2016-07-05

Stress in office environments is a big concern, often leading to burn-out. New technologies are emerging, such as easily available sensors, contextual reasoning, and electronic coaching (e-coaching) apps. In the Smart Reasoning for Well-being at Home and at Work (SWELL) project, we explore the potential of using such new pervasive technologies to provide support for the self-management of well-being, with a focus on individuals' stress-coping. Ideally, these new pervasive systems should be grounded in existing work stress and intervention theory. However, there is a large diversity of theories and they hardly provide explicit directions for technology design. The aim of this paper is to present a comprehensive and concise framework that can be used to design pervasive technologies that support knowledge workers to decrease stress. Based on a literature study we identify concepts relevant to well-being at work and select different work stress models to find causes of work stress that can be addressed. From a technical perspective, we then describe how sensors can be used to infer stress and the context in which it appears, and use intervention theory to further specify interventions that can be provided by means of pervasive technology. The resulting general framework relates several relevant theories: we relate "engagement and burn-out" to "stress", and describe how relevant aspects can be quantified by means of sensors. We also outline underlying causes of work stress and how these can be addressed with interventions, in particular utilizing new technologies integrating behavioral change theory. Based upon this framework we were able to derive requirements for our case study, the pervasive SWELL system, and we implemented two prototypes. Small-scale user studies proved the value of the derived technology-supported interventions. The presented framework can be used to systematically develop theory-based technology-supported interventions to address work stress. In the area of pervasive systems for well-being, we identified the following six key research challenges and opportunities: (1) performing multi-disciplinary research, (2) interpreting personal sensor data, (3) relating measurable aspects to burn-out, (4) combining strengths of human and technology, (5) privacy, and (6) ethics.

Acute stress switches spatial navigation strategy from egocentric to allocentric in a virtual Morris water maze.

PubMed

van Gerven, Dustin J H; Ferguson, Thomas; Skelton, Ronald W

2016-07-01

Stress and stress hormones are known to influence the function of the hippocampus, a brain structure critical for cognitive-map-based, allocentric spatial navigation. The caudate nucleus, a brain structure critical for stimulus-response-based, egocentric navigation, is not as sensitive to stress. Evidence for this comes from rodent studies, which show that acute stress or stress hormones impair allocentric, but not egocentric navigation. However, there have been few studies investigating the effect of acute stress on human spatial navigation, and the results of these have been equivocal. To date, no study has investigated whether acute stress can shift human navigational strategy selection between allocentric and egocentric navigation. The present study investigated this question by exposing participants to an acute psychological stressor (the Paced Auditory Serial Addition Task, PASAT), before testing navigational strategy selection in the Dual-Strategy Maze, a modified virtual Morris water maze. In the Dual-Strategy maze, participants can chose to navigate using a constellation of extra-maze cues (allocentrically) or using a single cue proximal to the goal platform (egocentrically). Surprisingly, PASAT stress biased participants to solve the maze allocentrically significantly more, rather than less, often. These findings have implications for understanding the effects of acute stress on cognitive function in general, and the function of the hippocampus in particular. Copyright © 2016 Elsevier Inc. All rights reserved.

Teacher stress and health; examination of a model.

PubMed

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.

Effects of cognitive-behavioural therapy on anxiety for children with high-functioning autistic spectrum disorders.

PubMed

Ooi, Y P; Lam, C M; Sung, M; Tan, W T S; Goh, T J; Fung, D S S; Pathy, P; Ang, R P; Chua, A

2008-03-01

Children with autistic spectrum disorders (ASD) often exhibit one or more comorbid disorders, including anxiety, disruptive behaviour, mental retardation, and depression. Various studies have documented the effectiveness of cognitive-behavioural therapy (CBT) in treating children with anxiety. Although studies have indicated a high prevalence of anxiety in individuals with ASD, there is a lack of systematic studies substantiating the effectiveness of cognitive-behavioural interventions among children with high-functioning autism. This pilot study investigated the effects of a 16-session CBT programme on six high-functioning children diagnosed with ASD (mean age 11.50 years, standard deviation 0.84 years). These children were diagnosed with ASD or Asperger's syndrome by the DSM-IV criteria. Measures on levels of child's anxiety, parental and teacher stress were administered at pre- and post-treatment. Children showed lower levels of anxiety at post-treatment. Parents and teachers also reported lower levels of stress following the CBT programme. Findings from the present study provided some evidence of the effects of CBT for high-functioning autistic children in reducing anxiety, parental and teacher stress. Interpretation of the findings, recommendations for future research and implications of the present study are presented.

Hybrid-Wing-Body Vehicle Composite Fuselage Analysis and Case Study

NASA Technical Reports Server (NTRS)

Mukhopadhyay, Vivek

2014-01-01

Recent progress in the structural analysis of a Hybrid Wing-Body (HWB) fuselage concept is presented with the objective of structural weight reduction under a set of critical design loads. This pressurized efficient HWB fuselage design is presently being investigated by the NASA Environmentally Responsible Aviation (ERA) project in collaboration with the Boeing Company, Huntington Beach. The Pultruded Rod-Stiffened Efficient Unitized Structure (PRSEUS) composite concept, developed at the Boeing Company, is approximately modeled for an analytical study and finite element analysis. Stiffened plate linear theories are employed for a parametric case study. Maximum deflection and stress levels are obtained with appropriate assumptions for a set of feasible stiffened panel configurations. An analytical parametric case study is presented to examine the effects of discrete stiffener spacing and skin thickness on structural weight, deflection and stress. A finite-element model (FEM) of an integrated fuselage section with bulkhead is developed for an independent assessment. Stress analysis and scenario based case studies are conducted for design improvement. The FEM model specific weight of the improved fuselage concept is computed and compared to previous studies, in order to assess the relative weight/strength advantages of this advanced composite airframe technology

Regulation of Cadmium-Induced Proteomic and Metabolic Changes by 5-Aminolevulinic Acid in Leaves of Brassica napus L.

PubMed Central

Ali, Basharat; Gill, Rafaqat A.; Yang, Su; Gill, Muhammad B.; Farooq, Muhammad A.; Liu, Dan; Daud, Muhammad K.; Ali, Shafaqat; Zhou, Weijun

2015-01-01

It is evident from previous reports that 5-aminolevulinic acid (ALA), like other known plant growth regulators, is effective in countering the injurious effects of heavy metal-stress in oilseed rape (Brassica napus L.). The present study was carried out to explore the capability of ALA to improve cadmium (Cd2+) tolerance in B. napus through physiological, molecular, and proteomic analytical approaches. Results showed that application of ALA helped the plants to adjust Cd2+-induced metabolic and photosynthetic fluorescence changes in the leaves of B. napus under Cd2+ stress. The data revealed that ALA treatment enhanced the gene expressions of antioxidant enzyme activities substantially and could increase the expression to a certain degree under Cd2+ stress conditions. In the present study, 34 protein spots were identified that differentially regulated due to Cd2+ and/or ALA treatments. Among them, 18 proteins were significantly regulated by ALA, including the proteins associated with stress related, carbohydrate metabolism, catalysis, dehydration of damaged protein, CO2 assimilation/photosynthesis and protein synthesis/regulation. From these 18 ALA-regulated proteins, 12 proteins were significantly down-regulated and 6 proteins were up-regulated. Interestingly, it was observed that ALA-induced the up-regulation of dihydrolipoyl dehydrogenase, light harvesting complex photo-system II subunit 6 and 30S ribosomal proteins in the presence of Cd2+ stress. In addition, it was also observed that ALA-induced the down-regulation in thioredoxin-like protein, 2, 3-bisphosphoglycerate, proteasome and thiamine thiazole synthase proteins under Cd2+ stress. Taken together, the present study sheds light on molecular mechanisms involved in ALA-induced Cd2+ tolerance in B. napus leaves and suggests a more active involvement of ALA in plant physiological processes than previously proposed. PMID:25909456

Seawater inhalation induces acute lung injury via ROS generation and the endoplasmic reticulum stress pathway.

PubMed

Li, Peng-Cheng; Wang, Bo-Rong; Li, Cong-Cong; Lu, Xi; Qian, Wei-Sheng; Li, Yu-Juan; Jin, Fa-Guang; Mu, De-Guang

2018-05-01

Seawater (SW) inhalation can induce acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). In the present study, SW induced apoptosis of rat alveolar epithelial cells and histopathological alterations to lung tissue. Furthermore, SW administration increased generation of reactive oxygen species (ROS), whereas pretreatment with the ROS scavenger, N‑acetyl‑L‑cysteine (NAC), significantly decreased ROS generation, apoptosis and histopathological alterations. In addition, SW exposure upregulated the expression levels of glucose‑regulated protein 78 (GRP78) and CCAAT/enhancer binding protein homologous protein (CHOP), which are critical proteins in the endoplasmic reticulum (ER) stress response, thus indicating that SW may activate ER stress. Conversely, blocking ER stress with 4‑phenylbutyric acid (4‑PBA) significantly improved SW‑induced apoptosis and histopathological alterations, whereas an ER stress inducer, thapsigargin, had the opposite effect. Furthermore, blocking ROS with NAC inhibited SW‑induced ER stress, as evidenced by the downregulation of GRP78, phosphorylated (p)‑protein kinase R‑like ER kinase (PERK), p‑inositol‑requiring kinase 1α (IRE1α), p‑50 activating transcription factor 6α and CHOP. In addition, blocking ER stress with 4‑PBA decreased ROS generation. In conclusion, the present study indicated that ROS and ER stress pathways, which are involved in alveolar epithelial cell apoptosis, are important in the pathogenesis of SW‑induced ALI.

Psychological stress in a Japanese population with systemic lupus erythematosus: finding from KYSS study.

PubMed

Takahashi, Hiroki; Washio, Masakazu; Kiyohara, Chikako; Tada, Yoshifumi; Asami, Toyoko; Ide, Saburo; Atsumi, Tatsuya; Kobashi, Gen; Yamamoto, Motohisa; Horiuchi, Takahiko

2014-05-01

Daily psychological stress has been proposed as a risk factor for systemic lupus erythematosus (SLE) in Western countries. However, there is little information about the relationship between daily psychological stress and the risk of SLE in a Japanese population. We examined the association between SLE and daily psychological stress. A case-control study was conducted to examine the relationship between daily psychological stress and SLE in Japanese females. The participants were 160 female SLE patients and 660 female volunteers. Unconditional logistic regression was used to compute OR and 95% confidence interval (CI), with adjustment for several covariates. Smoking (OR = 2.59; 95% CI, 1.74-3.86), walking (OR = 1.75; 95% CI, 1.81-2.56) and daily psychological stress (OR = 1.88; 95% CI, 1.14-3.10) were increased in patients with SLE after adjusting for age, region and all factors. Smokers with daily psychological stress (OR = 4.70; 95% CI = 2.53-8.77) were more prevalent than nonsmokers without daily psychological stress in SLE. The multiplicative interaction measures between smoking status and daily psychological stress did not reach statistical significance. The present study suggests the possibility that daily psychological stress as well as smoking might be associated with an increased risk of SLE.

Factors related to stress and coping among Chinese nurses in Hong Kong.

PubMed

Callaghan, P; Tak-Ying, S A; Wyatt, P A

2000-06-01

Few empirical studies have investigated the issues linked to Hong Kong nurses work-related health. The present study investigated factors related to stress and coping among Chinese nurses in Hong Kong. The researchers employed a cross-sectional survey and made within-group comparisons of nurses' stress and coping. Using stratified random sampling the researchers selected nurses from the mailing list of a local professional organization. One hundred and sixty-eight (33.6%) nurses responded. Nurses reported lower stress levels than other workers assessed with the same measure. Paediatric nurses reported the highest stress levels. Nurses at the lower grades reported higher stress levels than nurses at the higher grades. Single nurses had marginally higher stress scores than married nurses and females had slightly higher stress scores than males. However, none of these results were statistically significant. The respondents' major sources of stress were related to nursing issues like too much work, interpersonal relationships, and dealing with hospital administration. The respondents coped with their stresses by seeking support from friends and colleagues, using different cognitive strategies and through leisure activities. There was a statistically significant link between the respondents' stress and sickness levels. The results raise issues about the nature of nurses' working experiences.

Adulthood stress responses in rats are variably altered as a factor of adolescent stress exposure.

PubMed

Moore, Nicole L T; Altman, Daniel E; Gauchan, Sangeeta; Genovese, Raymond F

2016-05-01

Stress exposure during development may influence adulthood stress response severity. The present study investigates persisting effects of two adolescent stressors upon adulthood response to predator exposure (PE). Rats were exposed to underwater trauma (UWT) or PE during adolescence, then to PE after reaching adulthood. Rats were then exposed to predator odor (PO) to test responses to predator cues alone. Behavioral and neuroendocrine assessments were conducted to determine acute effects of each stress experience. Adolescent stress altered behavioral response to adulthood PE. Acoustic startle response was blunted. Bidirectional changes in plus maze exploration were revealed as a factor of adolescent stress type. Neuroendocrine response magnitude did not predict severity of adolescent or adult stress response, suggesting that different adolescent stress events may differentially alter developmental outcomes regardless of acute behavioral or neuroendocrine response. We report that exposure to two different stressors in adolescence may differentially affect stress response outcomes in adulthood. Acute response to an adolescent stressor may not be consistent across all stressors or all dependent measures, and may not predict alterations in developmental outcomes pertaining to adulthood stress exposure. Further studies are needed to characterize factors underlying long-term effects of a developmental stressor.

Subjective Stress, Salivary Cortisol, and Electrophysiological Responses to Psychological Stress

PubMed Central

Qi, Mingming; Gao, Heming; Guan, Lili; Liu, Guangyuan; Yang, Juan

2016-01-01

The present study aimed to investigate the subjective stress, salivary cortisol, and electrophysiological responses to psychological stress induced by a modified version of a mental arithmetic task. Fifteen participants were asked to estimate whether the multiplication product of two-decimal numbers was above 10 or not either with a time limit (the stress condition) or without a time limit (the control condition). The results showed that participants reported higher levels of stress, anxiety, and negative affect in the stress condition than they did in the control condition. Moreover, the salivary cortisol level continued to increase after the stress condition but exhibited a sharp decrease after the control condition. In addition, the electrophysiological data showed that the amplitude of the frontal-central N1 component was larger for the stress condition than it was for the control condition, while the amplitude of the frontal-central P2 component was larger for the control condition than it was for the stress condition. Our study suggests that the psychological stress characteristics of time pressure and social-evaluative threat caused dissociable effects on perception and on the subsequent attentional resource allocation of visual information. PMID:26925026

Agmatine attenuates chronic unpredictable mild stress induced behavioral alteration in mice.

PubMed

Taksande, Brijesh G; Faldu, Dharmesh S; Dixit, Madhura P; Sakaria, Jay N; Aglawe, Manish M; Umekar, Milind J; Kotagale, Nandkishor R

2013-11-15

Chronic stress exposure and resulting dysregulation of the hypothalamic pituitary adrenal axis develops susceptibility to variety of neurological and psychiatric disorders. Agmatine, a putative neurotransmitter has been reported to be released in response to various stressful stimuli to maintain the homeostasis. Present study investigated the role of agmatine on chronic unpredictable mild stress (CUMS) induced behavioral and biochemical alteration in mice. Exposure of mice to CUMS protocol for 28 days resulted in diminished performance in sucrose preference test, splash test, forced swim test and marked elevation in plasma corticosterone levels. Chronic agmatine (5 and 10 mg/kg, ip, once daily) treatment started on day-15 and continued till the end of the CUMS protocol significantly increased sucrose preference, improved self-care and motivational behavior in the splash test and decreased duration of immobility in the forced swim test. Agmatine treatment also normalized the elevated corticosterone levels and prevented the body weight changes in chronically stressed animals. The pharmacological effect of agmatine was comparable to selective serotonin reuptake inhibitor, fluoxetine (10mg/kg, ip). Results of present study clearly demonstrated the anti-depressant like effect of agmatine in chronic unpredictable mild stress induced depression in mice. Thus the development of drugs based on brain agmatinergic modulation may represent a new potential approach for the treatment of stress related mood disorders like depression. © 2013 Published by Elsevier B.V.

Work-related stress in midlife is associated with higher number of mobility limitation in older age-results from the FLAME study.

PubMed

Kulmala, Jenni; Hinrichs, Timo; Törmäkangas, Timo; von Bonsdorff, Mikaela B; von Bonsdorff, Monika E; Nygård, Clas-Håkan; Klockars, Matti; Seitsamo, Jorma; Ilmarinen, Juhani; Rantanen, Taina

2014-01-01

The aim of this study is to investigate whether work-related stress symptoms in midlife are associated with a number of mobility limitations during three decades from midlife to late life. Data for the study come from the Finnish Longitudinal Study of Municipal Employees (FLAME). The study includes a total of 5429 public sector employees aged 44-58 years at baseline who had information available on work-related stress symptoms in 1981 and 1985 and mobility limitation score during the subsequent 28-year follow-up. Four midlife work-related stress profiles were identified: negative reactions to work and depressiveness, perceived decrease in cognition, sleep disturbances, and somatic symptoms. People with a high number of stress symptoms in 1981 and 1985 were categorized as having constant stress. The number of self-reported mobility limitations was computed based on an eight-item list of mobility tasks presented to the participants in 1992, 1997, and 2009. Data were analyzed using joint Poisson regression models. The study showed that depending on the stress profile, persons suffering from constant stress in midlife had a higher risk of 30-70 % for having one more mobility limitation during the following 28 years compared to persons without stress after adjusting for mortality, several lifestyle factors, and chronic conditions. A less pronounced risk increase (20-40 %) was observed for persons with occasional symptoms. The study suggests that effective interventions aiming to reduce work-related stress should focus on both primary and secondary prevention.

The Montreal Imaging Stress Task: using functional imaging to investigate the effects of perceiving and processing psychosocial stress in the human brain

PubMed Central

Dedovic, Katarina; Renwick, Robert; Mahani, Najmeh Khalili; Engert, Veronika; Lupien, Sonia J.; Pruessner, Jens C.

2005-01-01

Objective We developed a protocol for inducing moderate psychologic stress in a functional imaging setting and evaluated the effects of stress on physiology and brain activation. Methods The Montreal Imaging Stress Task (MIST), derived from the Trier Mental Challenge Test, consists of a series of computerized mental arithmetic challenges, along with social evaluative threat components that are built into the program or presented by the investigator. To allow the effects of stress and mental arithmetic to be investigated separately, the MIST has 3 test conditions (rest, control and experimental), which can be presented in either a block or an event-related design, for use with functional magnetic resonance imaging (fMRI) or positron emission tomography (PET). In the rest condition, subjects look at a static computer screen on which no tasks are shown. In the control condition, a series of mental arithmetic tasks are displayed on the computer screen, and subjects submit their answers by means of a response interface. In the experimental condition, the difficulty and time limit of the tasks are manipulated to be just beyond the individual's mental capacity. In addition, in this condition the presentation of the mental arithmetic tasks is supplemented by a display of information on individual and average performance, as well as expected performance. Upon completion of each task, the program presents a performance evaluation to further increase the social evaluative threat of the situation. Results In 2 independent studies using PET and a third independent study using fMRI, with a total of 42 subjects, levels of salivary free cortisol for the whole group were significantly increased under the experimental condition, relative to the control and rest conditions. Performing mental arithmetic was linked to activation of motor and visual association cortices, as well as brain structures involved in the performance of these tasks (e.g., the angular gyrus). Conclusions We propose the MIST as a tool for investigating the effects of perceiving and processing psychosocial stress in functional imaging studies. PMID:16151536

Stress on the College Campus.

ERIC Educational Resources Information Center

Gill, Wanda E.

A Stress Test designed to help college students increase awareness of stress and ways they deal with it is presented, along with suggestions to reduce stress. The stress test was presented at a workshop by George Washington University graduate students. The test's four scales measure ways that students cope with stress and the student's…

Localization of Secondary Metabolites in Marine Invertebrates: Contribution of MALDI MSI for the Study of Saponins in Cuvierian Tubules of H. forskali

PubMed Central

Meriaux, Céline; Bonnel, David; Salzet, Michel; Fournier, Isabelle; Wisztorski, Maxence

2010-01-01

Background Several species of sea cucumbers of the family Holothuriidae possess a particular mechanical defense system called the Cuvierian tubules (Ct). It is also a chemical defense system as triterpene glycosides (saponins) appear to be particularly concentrated in Ct. In the present study, the precise localization of saponins in the Ct of Holothuria forskali is investigated. Classical histochemical labeling using lectin was firstly performed but did not generate any conclusive results. Thus, MALDI mass spectrometry Imaging (MALDI-MSI) was directly applied and completed by statistical multivariate tests. A comparison between the tubules of relaxed and stressed animals was realized. Results These analyses allowed the detection of three groups of ions, corresponding to the isomeric saponins of the tubules. Saponins detected at m/z 1287 and 1303 were the most abundant and were apparently localized in the connective tissue of the tubules of both relaxed and stressed individuals. Saponins at m/z 1125 and 1141 were detected in lower amount and were present in tissues of relaxed animals. Finally, saponin ions at 1433, 1449, 1463 and 1479 were observed in some Ct of stressed holothuroids in the outer part of the connective tissue. The saponin group m/z 14xx seems therefore to be stress-specific and could originate from modifications of the saponins with m/z of 11xx. Conclusions All the results taken together indicate a complex chemical defense mechanism with, for a single organ, different sets of saponins originating from different cell populations and presenting different responses to stress. The present study also reflects that MALDI-MSI is a valuable tool for chemical ecology studies in which specific chemical signalling molecules like allelochemicals or pheromones have to be tracked. This report represents one of the very first studies using these tools to provide a functional and ecological understanding of the role of natural products from marine invertebrates. PMID:21085713

Preventive effect of theanine intake on stress-induced impairments of hippocamapal long-term potentiation and recognition memory.

PubMed

Tamano, Haruna; Fukura, Kotaro; Suzuki, Miki; Sakamoto, Kazuhiro; Yokogoshi, Hidehiko; Takeda, Atsushi

2013-06-01

Theanine, γ-glutamylethylamide, is one of the major amino acid components in green tea. On the basis of the preventive effect of theanine intake after birth on mild stress-induced attenuation of hippocamapal CA1 long-term potentiation (LTP), the present study evaluated the effect of theanine intake after weaning on stress-induced impairments of LTP and recognition memory. Young rats were fed water containing 0.3% theanine for 3 weeks after weaning and subjected to water immersion stress for 30min, which was more severe than tail suspension stress for 30s used previously. Serum corticosterone levels were lower in theanine-administered rats than in the control rats even after exposure to stress. CA1 LTP induced by a 100-Hz tetanus for 1s was inhibited in the presence of 2-amino-5-phosphonovalerate (APV), an N-methyl-d-aspartate (NMDA) receptor antagonist, in hippocampal slices from the control rats and was attenuated by water immersion stress. In contrast, CA1 LTP was not significantly inhibited in the presence of APV in hippocampal slices from theanine-administered rats and was not attenuated by the stress. Furthermore, object recognition memory was impaired in the control rats, but not in theanine-administered rats. The present study indicates the preventive effect of theanine intake after weaning on stress-induced impairments of hippocampal LTP and recognition memory. It is likely that the modification of corticosterone secretion after theanine intake is involved in the preventive effect. Copyright © 2013 Elsevier Inc. All rights reserved.

Ratcheting fatigue behavior of Zircaloy-2 at room temperature

NASA Astrophysics Data System (ADS)

Rajpurohit, R. S.; Sudhakar Rao, G.; Chattopadhyay, K.; Santhi Srinivas, N. C.; Singh, Vakil

2016-08-01

Nuclear core components of zirconium alloys experience asymmetric stress or strain cycling during service which leads to plastic strain accumulation and drastic reduction in fatigue life as well as dimensional instability of the component. Variables like loading rate, mean stress, and stress amplitude affect the influence of asymmetric loading. In the present investigation asymmetric stress controlled fatigue tests were conducted with mean stress from 80 to 150 MPa, stress amplitude from 270 to 340 MPa and stress rate from 30 to 750 MPa/s to study the process of plastic strain accumulation and its effect on fatigue life of Zircaloy-2 at room temperature. It was observed that with increase in mean stress and stress amplitude accumulation of ratcheting strain was increased and fatigue life was reduced. However, increase in stress rate led to improvement in fatigue life due to less accumulation of ratcheting strain.

European adolescents' level of perceived stress and its relationship with body adiposity--the HELENA Study.

PubMed

De Vriendt, Tineke; Clays, Els; Maes, Lea; De Bourdeaudhuij, Ilse; Vicente-Rodriguez, Germàn; Moreno, Luis A; Nagy, Eniko; Molnár, Dénes; Ortega, Francisco B; Dietrich, Sabine; Manios, Yannis; De Henauw, Stefaan

2012-08-01

Since stress is hypothesized to be involved in the aetiology of obesity, the present study examined the current perception of stress in European adolescents and the association between adolescent perceived stress and their adiposity. Observational data from 1121 adolescents aged 12.5-17.5 years from six European cities involved in the Healthy Lifestyle in Europe by Nutrition in Adolescence cross-sectional study, was investigated. The adolescents completed the adolescent stress questionnaire, comprising 10 different stress dimensions. Anthropometric measurements (weight, height, skinfold thicknesses and circumferences) and bioelectrical impedance analysis were performed, and personal characteristics (age, pubertal stage and parental education) were collected. The measures of perceived stress were described for boys and girls separately and gender differences were investigated. Associations between the adolescents' perceived stress and indicators of general (body mass index z-score, sum of skinfold thicknesses and body fat%) and abdominal (waist and hip circumference, and waist/height ratio) adiposity were examined using hierarchical linear models. While girls reported systematically higher levels of stress compared with boys, their stress profiles were similar, with highest levels for school-related stress followed by future uncertainty. Only in girls, perceived stress was significantly associated with increased measures of general and abdominal adiposity. In boys, no relationship between perceived stress and adiposity measures was observed. School is reported to be an important source of adolescent stress and should be the focus of stress management campaigns. Only in girls, the hypothesis that stress might be involved in the aetiology of obesity during adolescence was supported.

Survey of Turbulence Models for the Computation of Turbulent Jet Flow and Noise

NASA Technical Reports Server (NTRS)

Nallasamy, N.

1999-01-01

The report presents an overview of jet noise computation utilizing the computational fluid dynamic solution of the turbulent jet flow field. The jet flow solution obtained with an appropriate turbulence model provides the turbulence characteristics needed for the computation of jet mixing noise. A brief account of turbulence models that are relevant for the jet noise computation is presented. The jet flow solutions that have been directly used to calculate jet noise are first reviewed. Then, the turbulent jet flow studies that compute the turbulence characteristics that may be used for noise calculations are summarized. In particular, flow solutions obtained with the k-e model, algebraic Reynolds stress model, and Reynolds stress transport equation model are reviewed. Since, the small scale jet mixing noise predictions can be improved by utilizing anisotropic turbulence characteristics, turbulence models that can provide the Reynolds stress components must now be considered for jet flow computations. In this regard, algebraic stress models and Reynolds stress transport models are good candidates. Reynolds stress transport models involve more modeling and computational effort and time compared to algebraic stress models. Hence, it is recommended that an algebraic Reynolds stress model (ASM) be implemented in flow solvers to compute the Reynolds stress components.

The quality of fetal arm movements as indicators of fetal stress.

PubMed

Reissland, Nadja; Francis, Brian

2010-12-01

Although a number of studies have found that maternal stress affects the fetus, it is unclear whether jerky fetal movements observed on ultrasound scans are indicative of fetal stress, or whether they are part of normal development. The present study was designed to examine the relationship between jerky fetal arm movements in relation to fetal age and stress. Video recordings were made of routine ultrasound scans of 57 fetuses (age range 8 to 33 weeks) classified into three age groups: 1st trimester (8-12 weeks, N=9), 2nd trimester (13-24 weeks, N=38), and 3rd trimester (26-33 weeks, N=10). Following previous research on stress behaviour in neonates, a fetal index of stress was derived from frequency of hiccup, back arch and rhythmical mouthing. Results indicated that while stress level was unrelated to fetal age, jerkiness of arm movements was significantly associated with the fetal stress index but not age. Our findings suggest that jerky arm movements in fetuses are suggestive of fetal stress. Copyright © 2010 Elsevier Ltd. All rights reserved.

Effect of sulfonylureas administered centrally on the blood glucose level in immobilization stress model.

PubMed

Sharma, Naveen; Sim, Yun-Beom; Park, Soo-Hyun; Lim, Su-Min; Kim, Sung-Su; Jung, Jun-Sub; Hong, Jae-Seung; Suh, Hong-Won

2015-05-01

Sulfonylureas are widely used as an antidiabetic drug. In the present study, the effects of sulfonylurea administered supraspinally on immobilization stress-induced blood glucose level were studied in ICR mice. Mice were once enforced into immobilization stress for 30 min and returned to the cage. The blood glucose level was measured 30, 60, and 120 min after immobilization stress initiation. We found that intracerebroventricular (i.c.v.) injection with 30 µg of glyburide, glipizide, glimepiride or tolazamide attenuated the increased blood glucose level induced by immobilization stress. Immobilization stress causes an elevation of the blood corticosterone and insulin levels. Sulfonylureas pretreated i.c.v. caused a further elevation of the blood corticosterone level when mice were forced into the stress. In addition, sulfonylureas pretreated i.c.v. alone caused an elevation of the plasma insulin level. Furthermore, immobilization stress-induced insulin level was reduced by i.c.v. pretreated sulfonylureas. Our results suggest that lowering effect of sulfonylureas administered supraspinally against immobilization stress-induced increase of the blood glucose level appears to be primarily mediated via elevation of the plasma insulin level.

Extraversion and cardiovascular responses to recurrent social stress: Effect of stress intensity.

PubMed

Lü, Wei; Xing, Wanying; Hughes, Brian M; Wang, Zhenhong

2017-10-28

The present study sought to establish whether the effects of extraversion on cardiovascular responses to recurrent social stress are contingent on stress intensity. A 2×5×1 mixed-factorial experiment was conducted, with social stress intensity as a between-subject variable, study phase as a within-subject variable, extraversion as a continuous independent variable, and cardiovascular parameter (HR, SBP, DBP, or RSA) as a dependent variable. Extraversion (NEO-FFI), subjective stress, and physiological stress were measured in 166 undergraduate students randomly assigned to undergo moderate (n=82) or high-intensity (n=84) social stress (a public speaking task with different levels of social evaluation). All participants underwent continuous physiological monitoring while facing two consecutive stress exposures distributed across five laboratory phases: baseline, stress exposure 1, post-stress 1, stress exposure 2, post-stress 2. Results indicated that under moderate-intensity social stress, participants higher on extraversion exhibited lesser HR reactivity to stress than participants lower on extraversion, while under high-intensity social stress, they exhibited greater HR, SBP, DBP and RSA reactivity. Under both moderate- and high-intensity social stress, participants higher on extraversion exhibited pronounced SBP and DBP response adaptation to repeated stress, and showed either better degree of HR recovery or greater amount of SBP and DBP recovery after stress. These findings suggest that individuals higher on extraversion exhibit physiological flexibility to cope with social challenges and benefit from adaptive cardiovascular responses. Copyright © 2017 Elsevier B.V. All rights reserved.

Stress-related endocrinological and psychopathological effects of short- and long-term 50Hz electromagnetic field exposure in rats.

PubMed

Szemerszky, Renáta; Zelena, Dóra; Barna, István; Bárdos, György

2010-01-15

It is believed that different electromagnetic fields do have beneficial and harmful biological effects. The aim of the present work was to study the long-term consequences of 50 Hz electromagnetic field (ELF-EMF) exposure with special focus on the development of chronic stress and stress-induced psychopathology. Adult male Sprague-Dawley rats were exposed to ELF-EMF (50 Hz, 0.5 mT) for 5 days, 8h daily (short) or for 4-6 weeks, 24h daily (long). Anxiety was studied in elevated plus maze test, whereas depression-like behavior of the long-treated group was examined in the forced swim test. Some days after behavioral examination, the animals were decapitated among resting conditions and organ weights, blood hormone levels as well as proopiomelanocortin mRNA level from the anterior lobe of the pituitary gland were measured. Both treatments were ineffective on somatic parameters, namely none of the changes characteristic to chronic stress (body weight reduction, thymus involution and adrenal gland hypertrophy) were present. An enhanced blood glucose level was found after prolonged ELF-EMF exposure (p=0.013). The hormonal stress reaction was similar in control and short-term exposed rats, but significant proopiomelanocortin elevation (p<0.000) and depressive-like behavior (enhanced floating time; p=0.006) were found following long-term ELF-EMF exposure. Taken together, long and continuous exposure to relatively high intensity electromagnetic field may count as a mild stress situation and could be a factor in the development of depressive state or metabolic disturbances. Although we should stress that the average intensity of the human exposure is normally much smaller than in the present experiment.

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

PubMed

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.

[GESTASTRES cohort study protocol on the effects of stress during pregnancy by measuring the cortisol in women's and newborn's hair].

PubMed

Caparros-Gonzalez, Rafael A; García-García, Inmaculada; Mariñas-Lirola, Juan Carlos; Peralta-Ramírez, Maria Isabel

2018-04-16

The aim was to present the longitudinal study protocol on the effects of perinatal stress from conception to one year of age. Stress is associated to psychopathological, cardiovascular and inmunological diseases. During pregnancy, the activation of the Hipotalamic-Pituitary-Adrenal results in an increased release of cortisol. Stress during pregnancy is related to maternal, fetal and infant negative outcomes that can last a lifetime. Nevertheless, contradictory findings have been reported. In this longitudinal study maternal stress is assessed from a sample of 807 pregnant women through hair cortisol levels and psychological question- naires during the three trimesters of pregnancy. Besides, associa- tions with the new-borns´ hair cortisol levels, temperament and neurodevelopment at age 6 and 12 months are assessed. Sociode- mographic, obstetrics, delivery, fetal and newborn development variables are included in analysis. Findings will be able to pro- vide a better understanding of perinatal stress and will improve maternal, fetal and infant outcomes.

Maternal serotonin transporter genotype affects risk for ASD with exposure to prenatal stress.

PubMed

Hecht, Patrick M; Hudson, Melissa; Connors, Susan L; Tilley, Michael R; Liu, Xudong; Beversdorf, David Q

2016-11-01

Stress exposure during gestation is implicated in several neuropsychiatric conditions, including autism spectrum disorder (ASD). Previous research showed that prenatal stress increases risk for ASD with peak exposure during the end of the second and the beginning of the third trimester. However, exposures to prenatal stress do not always result in ASD, suggesting that other factors may interact with environmental stressors to increase ASD risk. The present study examined a maternal genetic variation in the promoter region of the serotonin transporter gene (5-HTTLPR) affecting stress tolerance and its interaction with the effect of environmental stressors on risk for ASD. Two independent cohorts of mothers of ASD children recruited by the University of Missouri and Queen's University were surveyed regarding the prenatal environment and genotyping on 5-HTTLPR was performed to explore this relationship. In both samples, mothers of children with ASD carrying the stress susceptible short allele variant of 5-HTTLPR experienced a greater number of stressors and greater stress severity when compared to mothers carrying the long allele variant. The temporal peak of stressors during gestation in these mothers was consistent with previous findings. Additionally, increased exposure to prenatal stress was not reported in the pregnancies of typically developing siblings from the same mothers, regardless of maternal genotype, suggesting against the possibility that the short allele might increase the recall of stress during pregnancy. The present study provides further evidence of a specific maternal polymorphism that may affect the risk for ASD with exposure to prenatal stress. Autism Res 2016, 9: 1151-1160. © 2016 International Society for Autism Research, Wiley Periodicals, Inc. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.

Silicon Priming Created an Enhanced Tolerance in Alfalfa (Medicago sativa L.) Seedlings in Response to High Alkaline Stress.

PubMed

Liu, Duo; Liu, Miao; Liu, Xiao-Long; Cheng, Xian-Guo; Liang, Zheng-Wei

2018-01-01

Alkaline stress as a result of higher pH usually triggers more severe physiological damage to plants than that of saline stress with a neutral pH. In the present study, we demonstrated that silicon (Si) priming of alfalfa ( Medicago sativa L.) seedlings increased their tolerance to high alkaline stress situations. Gongnong No. 1 seedlings were subjected to alkaline stress simulated by 25 mM Na 2 CO 3 (pH 11.2). Alkaline stress greatly decreased the biomass and caused severe lodging or wilting of alfalfa seedlings. In contrast, the application of Si to alfalfa seedlings 36 h prior to the alkaline treatment significantly alleviated the damage symptoms and greatly increased the biomass and chlorophyll content. Because of being concomitant with increasing photosynthesis and water use efficiency, decreasing membrane injury and malondialdehyde content, and increasing peroxidase and catalase ascorbate activities in alfalfa leaves, thereby alleviating the triggered oxidative damage by alkaline stress to the plant. Furthermore, Si priming significantly decreased the accumulation of protein and proline content in alfalfa, thus reducing photosynthetic feedback repression. Si priming significantly accumulated more Na in the roots, but led to a decrease of Na accumulation and an increase of K accumulation in the leaves under alkaline stress. Meanwhile, Si priming decreased the accumulation of metal ions such as Mg, Fe, Mn, and Zn in the roots of alfalfa seedlings under alkaline stress. Collectively, these results suggested that Si is involved in the metabolic or physiological changes and has a potent priming effect on the alkaline tolerance of alfalfa seedlings. The present study indicated that Si priming is a new approach to improve the alkaline tolerance in alfalfa and provides increasing information for further exploration of the alkaline stress response at the molecular level in alfalfa.

The dual blocker of FAAH/TRPV1 N-arachidonoylserotonin reverses the behavioral despair induced by stress in rats and modulates the HPA-axis.

PubMed

Navarria, Andrea; Tamburella, Alessandra; Iannotti, Fabio A; Micale, Vincenzo; Camillieri, Giovanni; Gozzo, Lucia; Verde, Roberta; Imperatore, Roberta; Leggio, Gian Marco; Drago, Filippo; Di Marzo, Vincenzo

2014-09-01

In recent years, several studies have explored the involvement of the deregulation of the hypothalamus-pituitary-adrenal (HPA) axis in the pathophysiology of stress-related disorders. HPA hyper-activation as a consequence of acute/chronic stress has been found to play a major role in the neurobiological changes that are responsible for the onset of such states. Currently available medications for depression, one of the most relevant stress-related disorders, present several limitations, including a time lag for treatment response and low rates of efficacy. N-Arachidonoylserotonin (AA-5-HT), a dual blocker at fatty acid amide hydrolase (FAAH, the enzyme responsible for the inactivation of the endocannabinoid anandamide) and transient receptor potential vanilloid type-1 channel (TRPV1), produces anxiolytic-like effects in mice. The present study was designed to assess the capability of AA-5-HT to reverse the behavioral despair following exposure to stress in rats and the role of the HPA-axis. Behavioral tasks were performed, and corticosterone and endocannabinoid (anandamide and 2-arachidonoylglycerol) levels were measured in selected brain areas critically involved in the pathophysiology of stress-related disorders (medial PFC and hippocampus) under basal and stress conditions, and in response to treatment with AA-5-HT. Our data show that AA-5-HT reverses the rat behavioral despair in the forced swim test under stress conditions, and this effect is associated with the normalization of the HPA-axis deregulation that follows stress application and only in part with elevation of anandamide levels. Blockade of FAAH and TRPV1 may thus represent a novel target to design novel therapeutic strategies for the treatment of stress-related disorders. Copyright © 2014 Elsevier Ltd. All rights reserved.

Numerical Analysis of Stress Concentration in Isotropic and Laminated Plates with Inclined Elliptical Holes

NASA Astrophysics Data System (ADS)

Khechai, Abdelhak; Tati, Abdelouahab; Belarbi, Mohamed Ouejdi; Guettala, Abdelhamid

2018-03-01

The design of high-performance composite structures frequently includes discontinuities to reduce the weight and fastener holes for joining. Understanding the behavior of perforated laminates is necessary for structural design. In the current work, stress concentrations taking place in laminated and isotropic plates subjected to tensile load are investigated. The stress concentrations are obtained using a recent quadrilateral finite element of four nodes with 32 DOFs. The present finite element (PE) is a combination of two finite elements. The first finite element is a linear isoparametric membrane element and the second is a high precision Hermitian element. One of the essential objectives of the current investigation is to confirm the capability and efficiency of the PE for stress determination in perforated laminates. Different geometric parameters, such as the cutout form, sizes and cutout orientations, which have a considerable effect on the stress values, are studied. Using the present finite element formulation, the obtained results are found to be in good agreement with the analytical findings, which validates the capability and the efficiency of the proposed formulation. Finally, to understand the material parameters effect such as the orientation of fibers and degree of orthotropy ratio on the stress values, many figures are presented using different ellipse major to minor axis ratio. The stress concentration values are considerably affected by increasing the orientation angle of the fibers and degree of orthotropy.

The stress-buffering effects of a brief dyadic interaction before an acute stressor.

PubMed

Pauley, Perry M; Floyd, Kory; Hesse, Colin

2015-01-01

Although previous studies have confirmed that affectionate interaction can reduce the effects of stress, whether or not this effect is due more to habituation or the accumulation of affection remains an area of debate. The goal of the present study was to determine how specific acts of affection mitigate the effects of stress. Sixty mixed-sex dyads (half platonic friends and half dating partners) were randomly assigned to one of three conditions, affectionate interaction, quiet rest with the friend/romantic partner present, or separation from the friend/romantic partner, before one of the partners experienced a series of stressful activities. Results revealed that participants in the affection condition experienced the smallest increase in cardiovascular arousal regardless of relationship status. Participants' endocrine responses were more nuanced and depended on both their biological sex and the nature of the relationship with the companion. Given that these systems did not act in concert with one another, results provide mixed evidence for both an accumulation and habituation effect.

The oxidative stress response of myclobutanil and cyproconazole on Tetrahymena thermophila.

PubMed

Huang, Ai-Guo; Tu, Xiao; Liu, Lei; Wang, Gao-Xue; Ling, Fei

2016-01-01

Using Tetrahymena thermophila as experimental models, the oxidative stress of triazole fungicides myclobutanil (MYC) and cyproconazole (CYP) was investigated. Results showed that 24-h EC50 values for MYC and CYP were 16.67 (13.37-19.65) and 20.44 (18.85-21.96) mg/L, respectively; 48-h EC50 values for MYC and CYP were 14.31 (13.13-15.42) and 18.76 (17.09-20.31) mg/L, respectively. Reactive oxygen species was significantly induced and cytotoxicity was caused by MYC and CYP by increasing propidium iodide (PI) fluorescence. Damage of regular wrinkles and appearing of small holes on the cell surface were observed by SEM. Furthermore, MYC and CYP also caused notable changes in enzyme activities and mRNA levels. Overall, the present study points out that MYC and CYP lead to oxidative stress on T. thermophila. The information presented in this study will provide insights into the mechanism of triazoles-induced oxidative stress on T. thermophila. Copyright © 2015 Elsevier B.V. All rights reserved.

Stress Distribution During Deformation of Polycrystalline Aluminum by Molecular-Dynamics and Finite-Element Modeling

NASA Technical Reports Server (NTRS)

Yamakov, V.; Saether, E.; Phillips, D.; Glaessgen, E. H.

2004-01-01

In this paper, a multiscale modelling strategy is used to study the effect of grain-boundary sliding on stress localization in a polycrystalline microstructure with an uneven distribution of grain size. The development of the molecular dynamics (MD) analysis used to interrogate idealized grain microstructures with various types of grain boundaries and the multiscale modelling strategies for modelling large systems of grains is discussed. Both molecular-dynamics and finite-element (FE) simulations for idealized polycrystalline models of identical geometry are presented with the purpose of demonstrating the effectiveness of the adapted finite-element method using cohesive zone models to reproduce grain-boundary sliding and its effect on the stress distribution in a polycrystalline metal. The yield properties of the grain-boundary interface, used in the FE simulations, are extracted from a MD simulation on a bicrystal. The models allow for the study of the load transfer between adjacent grains of very different size through grain-boundary sliding during deformation. A large-scale FE simulation of 100 grains of a typical microstructure is then presented to reveal that the stress distribution due to grain-boundary sliding during uniform tensile strain can lead to stress localization of two to three times the background stress, thus suggesting a significant effect on the failure properties of the metal.

ER stress and genomic instability induced by gamma radiation in mice primary cultured glial cells.

PubMed

Chatterjee, Jit; Nairy, Rajesha K; Langhnoja, Jaldeep; Tripathi, Ashutosh; Patil, Rajashekhar K; Pillai, Prakash P; Mustak, Mohammed S

2018-06-01

Ionizing radiation induces various pathophysiological conditions by altering central nervous system (CNS) homeostasis, leading to neurodegenerative diseases. However, the potential effect of ionizing radiation response on cellular physiology in glial cells is unclear. In the present study, micronucleus test, comet assay, and RT-PCR were performed to investigate the potential effect of gamma radiation in cultured oligodendrocytes and astrocytes with respect to genomic instability, Endoplasmic Reticulum (ER) stress, and inflammation. Further, we studied the effect of alteration in ER stress specific gene expression in cortex post whole body radiation in mice. Results showed that exposure of gamma radiation of 2Gy in-vitro cultured astrocytes and oligodendrocytes and 7Gy in-vivo induced ER stress and Inflammation along with profuse DNA damage and Chromosomal abnormality. Additionally, we observed downregulation of myelin basic protein levels in cultured oligodendrocytes exposed to radiation. The present data suggests that ER stress and pro inflammatory cytokines serve as the major players in inducing glial cell dysfunction post gamma irradiation along with induction of genomic instability. Taken together, these results indicate that ER stress, DNA damage, and inflammatory pathways may be critical events leading to glial cell dysfunction and subsequent cell death following exposure to ionizing radiation.

Determination of wall shear stress from mean velocity and Reynolds shear stress profiles

NASA Astrophysics Data System (ADS)

Volino, Ralph J.; Schultz, Michael P.

2018-03-01

An analytical method is presented for determining the Reynolds shear stress profile in steady, two-dimensional wall-bounded flows using the mean streamwise velocity. The method is then utilized with experimental data to determine the local wall shear stress. The procedure is applicable to flows on smooth and rough surfaces with arbitrary pressure gradients. It is based on the streamwise component of the boundary layer momentum equation, which is transformed into inner coordinates. The method requires velocity profiles from at least two streamwise locations, but the formulation of the momentum equation reduces the dependence on streamwise gradients. The method is verified through application to laminar flow solutions and turbulent DNS results from both zero and nonzero pressure gradient boundary layers. With strong favorable pressure gradients, the method is shown to be accurate for finding the wall shear stress in cases where the Clauser fit technique loses accuracy. The method is then applied to experimental data from the literature from zero pressure gradient studies on smooth and rough walls, and favorable and adverse pressure gradient cases on smooth walls. Data from very near the wall are not required for determination of the wall shear stress. Wall friction velocities obtained using the present method agree with those determined in the original studies, typically to within 2%.

Ambiguity and uncertainty tolerance, need for cognition, and their association with stress. A study among Italian practicing physicians

PubMed Central

Iannello, Paola; Mottini, Anna; Tirelli, Simone; Riva, Silvia; Antonietti, Alessandro

2017-01-01

ABSTRACT Medical practice is inherently ambiguous and uncertain. The physicians’ ability to tolerate ambiguity and uncertainty has been proved to have a great impact on clinical practice. The primary aim of the present study was to test the hypothesis that higher degree of physicians’ ambiguity and uncertainty intolerance and higher need for cognitive closure will predict higher work stress. Two hundred and twelve physicians (mean age = 42.94 years; SD = 10.72) from different medical specialties with different levels of expertise were administered a set of questionnaires measuring perceived levels of work-related stress, individual ability to tolerate ambiguity, stress deriving from uncertainty, and personal need for cognitive closure. A linear regression analysis was performed to examine which variables predict the perceived level of stress. The regression model was statistically significant [R2 = .32; F(10,206) = 8.78, p ≤ .001], thus showing that, after controlling for gender and medical specialty, ambiguity and uncertainty tolerance, decisiveness (a dimension included in need for closure), and the years of practice were significant predictors of perceived work-related stress. Findings from the present study have some implications for medical education. Given the great impact that the individual ability to tolerate ambiguity and uncertainty has on the physicians’ level of perceived work-related stress, it would be worth paying particular attention to such a skill in medical education settings. It would be crucial to introduce or to empower educational tools and strategies that could increase medical students’ ability to tolerate ambiguity and uncertainty. Abbreviations: JSQ: Job stress questionnaire; NFCS: Need for cognitive closure scale; PRU: Physicians’ reactions to uncertainty; TFA: Tolerance for ambiguity PMID:28178917

Ambiguity and uncertainty tolerance, need for cognition, and their association with stress. A study among Italian practicing physicians.

PubMed

Iannello, Paola; Mottini, Anna; Tirelli, Simone; Riva, Silvia; Antonietti, Alessandro

2017-01-01

Medical practice is inherently ambiguous and uncertain. The physicians' ability to tolerate ambiguity and uncertainty has been proved to have a great impact on clinical practice. The primary aim of the present study was to test the hypothesis that higher degree of physicians' ambiguity and uncertainty intolerance and higher need for cognitive closure will predict higher work stress. Two hundred and twelve physicians (mean age = 42.94 years; SD = 10.72) from different medical specialties with different levels of expertise were administered a set of questionnaires measuring perceived levels of work-related stress, individual ability to tolerate ambiguity, stress deriving from uncertainty, and personal need for cognitive closure. A linear regression analysis was performed to examine which variables predict the perceived level of stress. The regression model was statistically significant [R 2  = .32; F(10,206) = 8.78, p ≤ .001], thus showing that, after controlling for gender and medical specialty, ambiguity and uncertainty tolerance, decisiveness (a dimension included in need for closure), and the years of practice were significant predictors of perceived work-related stress. Findings from the present study have some implications for medical education. Given the great impact that the individual ability to tolerate ambiguity and uncertainty has on the physicians' level of perceived work-related stress, it would be worth paying particular attention to such a skill in medical education settings. It would be crucial to introduce or to empower educational tools and strategies that could increase medical students' ability to tolerate ambiguity and uncertainty. JSQ: Job stress questionnaire; NFCS: Need for cognitive closure scale; PRU: Physicians' reactions to uncertainty; TFA: Tolerance for ambiguity.

Stressful life events increase aggression and alcohol use in young carriers of the GABRA2 rs279826/rs279858 A-allele.

PubMed

Kiive, Evelyn; Laas, Kariina; Vaht, Mariliis; Veidebaum, Toomas; Harro, Jaanus

2017-08-01

Research of GABRA2 gene in alcohol use and impulse control suggests its role in aggressive behaviour. The purpose of the present study was to examine the effects of GABRA2 genotype and stressful life events on aggressive behaviour, alcohol use frequency and occurrence of alcohol use disorder in a population representative sample of adolescents followed up from third grade to 25 years of age. The sample consisted of the younger cohort of the longitudinal Estonian Children Personality, Behaviour and Health Study. Aggressive behaviour was rated with the activity scale of af Klinteberg, Illinois Bully Scale and Buss-Perry Aggression Questionnaire. Stressful life events and alcohol use were self-reported. Life history of aggression and lifetime occurrence of psychiatric disorders were estimated in a structured interview. The sample was genotyped for GABRA2 rs279826 and rs279858 polymorphisms that are in strong linkage disequilibrium and yielded very similar findings: Higher number of stressful life events reported at age 15 was associated with increased fighting in A-allele carriers, but not in GG homozygotes. At age 25, A-allele carriers with more stressful life events scored higher on physical aggression than those with less stress, and this was also observed regarding life history of aggression. A-allele carriers exposed to higher stress had consumed alcoholic beverages more frequently at age 15, and by age 25, they had alcohol use disorder with higher prevalence. The results of the present study suggest that the GABRA2 genotype interacts with stress in young people with impact on the development of alcohol use and aggressive behaviour. Copyright © 2017 Elsevier B.V. and ECNP. All rights reserved.

Assessment of mental stress effects on prefrontal cortical activities using canonical correlation analysis: an fNIRS-EEG study.

PubMed

Al-Shargie, Fares; Tang, Tong Boon; Kiguchi, Masashi

2017-05-01

This paper presents an investigation about the effects of mental stress on prefrontal cortex (PFC) subregions using simultaneous measurement of functional Near-Infrared Spectroscopy (fNIRS) and Electroencephalography (EEG) signals. The aim is to explore canonical correlation analysis (CCA) technique to study the relationship among the bi-modality signals in mental stress assessment, and how we could fuse the signals for better accuracy in stress detection. Twenty-five male healthy subjects participated in the study while performing mental arithmetic task under control and stress (under time pressure with negative feedback) conditions. The fusion of brain signals acquired by fNIRS-EEG was performed at feature-level using CCA by maximizing the inter-subject covariance across modalities. The CCA result discovered the associations across the modalities and estimated the components responsible for these associations. The experiment results showed that mental stress experienced by this cohort of subjects is subregion specific and localized to the right ventrolateral PFC subregion. These suggest the right ventrolateral PFC as a suitable candidate region to extract biomarkers as performance indicators of neurofeedback training in stress coping.

Coping Work Strategies and Job Satisfaction Among Iranian Nurses

PubMed Central

Ghiyasvandian, Shahrzad; Adera Gebra, Addis

2014-01-01

Context: Nursing is a stressful job that could create physical and psychological disorders. Many studies presented information on stress, effects of coping strategies, and job satisfaction of nurses within health setting. We aimed to identify and describe nursing stresses, coping strategies and job satisfaction of Iranian nurses who are working or worked in different wards. Evidence Acquisition: In this review, we studied peer-reviewed journal articles on the field of stress, coping strategies and job satisfaction in nursing practice, especially Iranian nurses, which were published between 2000 and 2013. In this regard, we searched databases of PubMed, Elsevier, Google, BMJ, PMC, and MEDLINE. Results: The majority of the studies (60%) had analyzed the effect of coping strategies, experiences and perception of job-related stresses in Iranian nurses working in hospitals. In some of the reviewed studies (60%), the majority of the samples enrolled Iranian nurses. Forty percent of studies selected a maximum sample size of 565 (44%) participants in 2011. Nursing stress scale employed at 30% of the studies was the most commonly used strategy. This reviewed studies also revealed a combined measurement (60% of studies), based on categorical stress measurement, effects of coping strategies, and job satisfaction methods. Three studies explored the relationship between job stress and job satisfaction. For instance, the majority (74.4%) of nurses reported job satisfaction. Conclusions: Effect of coping strategies and job satisfaction on Iranian nurses is a well-accepted issue and has important positive outcomes on several areas of health discipline. PMID:25068050

Beneficial effect of daidzin in dry eye rat model through the suppression of inflammation and oxidative stress in the cornea.

PubMed

Xiao, Fan; Cui, Hua; Zhong, Xiao

2018-05-01

Present investigation evaluates the effect of daidzin in dry eye rat model through the suppression of inflammation and oxidative stress in the cornea. Briefly, electron spine resonance was used for the estimation of radical scavenging activity of daidzin and COX Fluorescent Activity Assay Kit was used for the estimation of PGS activity. Dry eye rat model was developed by removing the lacrimal gland and effect of daidzin was evaluated in dry eye rat model by estimating the fluorescein score, tear volume and expressions of heme oxigenase (HO-1), TNF α, Interlukin 6 (IL-6), matrix metallopeptidase 9 (MMP-9) and PGS-2. Result of the present study suggested that daidzin possess tyrosyl radical scavenging activity and thereby decreases the oxidative stress. Activity of PGS significantly increases in dry eye which was inhibited by daidzin treatment due to competitive inhibition of PGS. It also recovers the tear volume in dry eye rat model in which lacrimal gland was removed. Thus corneal erosion was improved by daidzin in dry eye rat model. Thus present study concludes that treatment with daidzin protects the cornea in dry eye rat model by suppression inflammation and oxidative stress.

Does methodology matter in eyewitness identification research? The effect of live versus video exposure on eyewitness identification accuracy.

PubMed

Pozzulo, Joanna D; Crescini, Charmagne; Panton, Tasha

2008-01-01

The present study examined the effect of mode of target exposure (live versus video) on eyewitness identification accuracy. Adult participants (N=104) were exposed to a staged crime that they witnessed either live or on videotape. Participants were then asked to rate their stress and arousal levels prior to being presented with either a target-present or -absent simultaneous lineup. Across target-present and -absent lineups, mode of target exposure did not have a significant effect on identification accuracy. However, mode of target exposure was found to have a significant effect on stress and arousal levels. Participants who witnessed the crime live had higher levels of stress and arousal than those who were exposed to the videotaped crime. A higher level of arousal was significantly related to poorer identification accuracy for those in the video condition. For participants in the live condition however, stress and arousal had no effect on eyewitness identification accuracy. Implications of these findings in regards to the generalizability of laboratory-based research on eyewitness testimony to real-life crime are discussed.

Psychophysiological effects of yoga on stress in college students.

PubMed

Tripathi, Mahesh Narain; Kumari, Sony; Ganpat, Tikhe Sham

2018-01-01

College students are vulnerable to a critical period in developmental maturation, facing rigorous academic work, and learning how to function independently. Physical activities such as running and bicycling have been shown to improve mood and relieve stress. However, college students often have low levels of physical activity. Yoga is an ancient physical and mental activity that affects mood and stress. However, studies examining the psychophysiological effects of yoga are rare in peer-reviewed journals. The aim of this study is to establish preliminary evidence for the psychophysiological effects of yoga on stress in young-adult college students. The present study suggests that yoga has positive effects on a psychophysiological level that leads to decreased levels of stress in college student. Further research is needed to examine the extent to which different types of yogic practices address the needs of different college subpopulations (e.g., overweight, sedentary, and smokers).

Environmental Enrichment Effect on Fecal Glucocorticoid Metabolites and Captive Maned Wolf (Chrysocyon brachyurus) Behavior.

PubMed

Coelho, Carlyle Mendes; de Azevedo, Cristiano Schetini; Guimarães, Marcelo Alcino de Barros Vaz; Young, Robert John

2016-01-01

Environmental enrichment is a technique that may reduce the stress of nonhuman animals in captivity. Stress may interfere with normal behavioral expression and affect cognitive decision making. Noninvasive hormonal studies can provide important information about the stress statuses of animals. This study evaluated the effectiveness of different environmental enrichment treatments in the diminution of fecal glucocorticoid metabolites (stress indicators) of three captive maned wolves (Chrysocyon brachyurus). Correlations of the fecal glucocorticoid metabolite levels with expressed behaviors were also determined. Results showed that environmental enrichment reduced fecal glucocorticoid metabolite levels. Furthermore, interspecific and foraging enrichment items were most effective in reducing stress in two of the three wolves. No definite pattern was found between behavioral and physiological responses to stress. In conclusion, these behavioral and physiological data showed that maned wolves responded positively from an animal well being perspective to the enrichment items presented.

Neuro-cognitive foundations of word stress processing - evidence from fMRI

PubMed Central

2011-01-01

Background To date, the neural correlates of phonological word stress processing are largely unknown. Methods In the present study, we investigated the processing of word stress and vowel quality using an identity matching task with pseudowords. Results In line with previous studies, a bilateral fronto-temporal network comprising the superior temporal gyri extending into the sulci as well as the inferior frontal gyri was observed for word stress processing. Moreover, we found differences in the superior temporal gyrus and the superior temporal sulcus, bilaterally, for the processing of different stress patterns. For vowel quality processing, our data reveal a substantial contribution of the left intraparietal cortex. All activations were modulated by task demands, yielding different patterns for same and different pairs of stimuli. Conclusions Our results suggest that the left superior temporal gyrus represents a basic system underlying stress processing to which additional structures including the homologous cortex site are recruited with increasing difficulty. PMID:21575209

Child involvement and stress in Greek mothers of deaf children.

PubMed

Lampropoulou, V; Konstantareas, M M

1998-10-01

Forty-two mothers of Greek deaf children reported their level of stress, availability of support, duration and frequency of involvement with their children, and affective tone of involvement, using an adaptation of Hill's ABCX model of stress and support (1949). Data on the interaction among six caregiving categories were collected over a 2-day period. Mothers of younger children and of boys, as well as mothers reporting greater stress, had longer and more frequent involvement. Mothers with greater stress were also more likely to rate the affective tone of their involvement as more neutral or as chorelike. Support availability was unrelated to involvement, with the exception of supporting neighbors. Compared to Canadian mothers of children both with and without disabilities, exposed to the same study protocol, the mothers in the present study were not more stressed. However, they were more likely to report a negative affective tone in their caregiving.

Putative bacterial volatile-mediated growth in soybean (Glycine max L. Merrill) and expression of induced proteins under salt stress.

PubMed

Vaishnav, A; Kumari, S; Jain, S; Varma, A; Choudhary, D K

2015-08-01

Plant root-associated rhizobacteria elicit plant immunity referred to as induced systemic tolerance (IST) against multiple abiotic stresses. Among multibacterial determinants involved in IST, the induction of IST and promotion of growth by putative bacterial volatile compounds (VOCs) is reported in the present study. To characterize plant proteins induced by putative bacterial VOCs, proteomic analysis was performed by MALDI-MS/MS after exposure of soybean seedlings to a new strain of plant growth promoting rhizobacteria (PGPR) Pseudomonas simiae strain AU. Furthermore, expression analysis by Western blotting confirmed that the vegetative storage protein (VSP), gamma-glutamyl hydrolase (GGH) and RuBisCo large chain proteins were significantly up-regulated by the exposure to AU strain and played a major role in IST. VSP has preponderant roles in N accumulation and mobilization, acid phosphatase activity and Na(+) homeostasis to sustain plant growth under stress condition. More interestingly, plant exposure to the bacterial strain significantly reduced Na(+) and enhanced K(+) and P content in root of soybean seedlings under salt stress. In addition, high accumulation of proline and chlorophyll content also provided evidence of protection against osmotic stress during the elicitation of IST by bacterial exposure. The present study reported for the first time that Ps. simiae produces a putative volatile blend that can enhance soybean seedling growth and elicit IST against 100 mmol l(-1) NaCl stress condition. The identification of such differentially expressed proteins provide new targets for future studies that will allow assessment of their physiological roles and significance in the response of glycophytes to stresses. Further work should uncover more about the chemical side of VOC compounds and a detailed study about their molecular mechanism responsible for plant growth. © 2015 The Society for Applied Microbiology.

Stress, burnout and depression: A systematic review on DNA methylation mechanisms.

PubMed

Bakusic, Jelena; Schaufeli, Wilmar; Claes, Stephan; Godderis, Lode

2017-01-01

Despite that burnout presents a serious burden for modern society, there are no diagnostic criteria. Additional difficulty is the differential diagnosis with depression. Consequently, there is a need to dispose of a burnout biomarker. Epigenetic studies suggest that DNA methylation is a possible mediator linking individual response to stress and psychopathology and could be considered as a potential biomarker of stress-related mental disorders. Thus, the aim of this review is to provide an overview of DNA methylation mechanisms in stress, burnout and depression. In addition to state-of-the-art overview, the goal of this review is to provide a scientific base for burnout biomarker research. We performed a systematic literature search and identified 25 pertinent articles. Among these, 15 focused on depression, 7 on chronic stress and only 3 on work stress/burnout. Three epigenome-wide studies were identified and the majority of studies used the candidate-gene approach, assessing 12 different genes. The glucocorticoid receptor gene (NR3C1) displayed different methylation patterns in chronic stress and depression. The serotonin transporter gene (SLC6A4) methylation was similarly affected in stress, depression and burnout. Work-related stress and depressive symptoms were associated with different methylation patterns of the brain derived neurotrophic factor gene (BDNF) in the same human sample. The tyrosine hydroxylase (TH) methylation was correlated with work stress in a single study. Additional, thoroughly designed longitudinal studies are necessary for revealing the cause-effect relationship of work stress, epigenetics and burnout, including its overlap with depression. Copyright © 2016 Elsevier Inc. All rights reserved.

The relationship between personality and the response to acute psychological stress.

PubMed

Xin, Yuanyuan; Wu, Jianhui; Yao, Zhuxi; Guan, Qing; Aleman, André; Luo, Yuejia

2017-12-04

The present study examined the relationship between personality traits and the response to acute psychological stress induced by a standardized laboratory stress induction procedure (the Trier Social Stress Test, TSST). The stress response was measured with a combination of cardiovascular reactivity, hypothalamic-pituitary-adrenal axis reactivity, and subjective affect (including positive affect, negative affect and subjective controllability) in healthy individuals. The Generalized Estimating Equations (GEE) approach was applied to account for the relationship between personality traits and stress responses. Results suggested that higher neuroticism predicted lower heart rate stress reactivity, lower cortisol stress response, more decline of positive affect and lower subjective controllability. Individuals higher in extraversion showed smaller cortisol activation to stress and less increase of negative affect. In addition, higher openness score was associated with lower cortisol stress response. These findings elucidate that neuroticism, extraversion and openness are important variables associated with the stress response and different dimensions of personality trait are associated with different aspects of the stress response.

Geomechanical simulation of the stress tensor rotation caused by injection of cold water in a deep geothermal reservoir

DOE PAGES

Jeanne, Pierre; Rutqvist, Jonny; Dobson, Patrick F.; ...

2015-11-12

We present a three-dimensional thermohydromechanical numerical study of the evolution and distribution of the stress tensor within the northwest part of The Geysers geothermal reservoir (in California), including a detailed study of the region around one injection well from 2003 to 2012. Initially, after imposing a normal faulting stress regime, we calculated local changes in the stress regime around injection wells. Our results were compared with previously published studies in which the stress state was inferred from inverting the focal plane mechanism of seismic events. Our main finding is that changes in stress tensor orientation are caused by injection-induced progressivemore » cooling of the reservoir, as well as by the seasonal variations in injection rate. Because of the gravity flow and cooling around a liquid zone formed by the injection, the vertical stress reduction is larger and propagates far below the injection well. At the same time, the horizontal stress increases, mostly because of stress redistribution below and above the cooling area. These two phenomena cause the rotation of the stress tensor and the appearance of a strike-slip regime above, inside, and below the cooling area. The cooling and the associated rotation of the stress regime can play a significant role in the observed long-term deepening of the microseismicity below active injection wells.« less

World assumptions, posttraumatic stress and quality of life after a natural disaster: a longitudinal study.

PubMed

Nygaard, Egil; Heir, Trond

2012-06-28

Changes in world assumptions are a fundamental concept within theories that explain posttraumatic stress disorder. The objective of the present study was to gain a greater understanding of how changes in world assumptions are related to quality of life and posttraumatic stress symptoms after a natural disaster. A longitudinal study of 574 Norwegian adults who survived the Southeast Asian tsunami in 2004 was undertaken. Multilevel analyses were used to identify which factors at six months post-tsunami predicted quality of life and posttraumatic stress symptoms two years post-tsunami. Good quality of life and posttraumatic stress symptoms were negatively related. However, major differences in the predictors of these outcomes were found. Females reported significantly higher quality of life and more posttraumatic stress than men. The association between level of exposure to the tsunami and quality of life seemed to be mediated by posttraumatic stress. Negative perceived changes in the assumption "the world is just" were related to adverse outcome in both quality of life and posttraumatic stress. Positive perceived changes in the assumptions "life is meaningful" and "feeling that I am a valuable human" were associated with higher levels of quality of life but not with posttraumatic stress. Quality of life and posttraumatic stress symptoms demonstrate differences in their etiology. World assumptions may be less specifically related to posttraumatic stress than has been postulated in some cognitive theories.

Design prediction for long term stress rupture service of composite pressure vessels

NASA Technical Reports Server (NTRS)

Robinson, Ernest Y.

1992-01-01

Extensive stress rupture studies on glass composites and Kevlar composites were conducted by the Lawrence Radiation Laboratory beginning in the late 1960's and extending to about 8 years in some cases. Some of the data from these studies published over the years were incomplete or were tainted by spurious failures, such as grip slippage. Updated data sets were defined for both fiberglass and Kevlar composite stand test specimens. These updated data are analyzed in this report by a convenient form of the bivariate Weibull distribution, to establish a consistent set of design prediction charts that may be used as a conservative basis for predicting the stress rupture life of composite pressure vessels. The updated glass composite data exhibit an invariant Weibull modulus with lifetime. The data are analyzed in terms of homologous service load (referenced to the observed median strength). The equations relating life, homologous load, and probability are given, and corresponding design prediction charts are presented. A similar approach is taken for Kevlar composites, where the updated stand data do show a turndown tendency at long life accompanied by a corresponding change (increase) of the Weibull modulus. The turndown characteristic is not present in stress rupture test data of Kevlar pressure vessels. A modification of the stress rupture equations is presented to incorporate a latent, but limited, strength drop, and design prediction charts are presented that incorporate such behavior. The methods presented utilize Cartesian plots of the probability distributions (which are a more natural display for the design engineer), based on median normalized data that are independent of statistical parameters and are readily defined for any set of test data.

Hardiness as a mediator between perceived stress and happiness in nurses.

PubMed

Abdollahi, A; Abu Talib, M; Yaacob, S N; Ismail, Z

2014-01-01

The relevance of the study of happiness and stress in nurses has been emphasized. In this sense, the intelligent use of hardiness is enable nurses to cope better with stress and contribute to being happier. This study aimed to examine the relationship among hardiness, perceived stress, and happiness in nurses. Moreover, we examined the mediator role of hardiness on the relationship between perceived stress and happiness in nurses. Our study revealed that hardi-attitude nurses evaluate situations as less stressful which results in a higher happiness. This study showed hardiness as being a protective factor against perceived stress and a facilitating factor for happiness in nurses. The findings could be important in training future nurses so that hardiness can be imparted, thereby giving them the ability to control their stress. Nursing is a stressful occupation with high levels of stress within the health professions. Given that hardiness is an important construct to enable nurses to cope better with stress and contribute to being happier; therefore, it is necessary we advance our knowledge about the aetiology of happiness, especially the role of hardiness in decreasing stress levels and increasing happiness. The present study sought to investigate the role of hardiness as a mediator between perceived stress and happiness. The participants, comprising 252 nurses from six private hospitals in Tehran, completed the Personal Views Survey, the Perceived Stress Scale, and the Oxford Happiness Inventory. Structural Equation Modelling (SEM) was used to analyse the data and answer the research hypotheses. As expected, hardiness partially mediated between perceived stress and happiness among nurses, and nurses with low levels of perceived stress were more likely to report greater hardiness and happiness. In addition, nurses with high levels of hardiness were more likely to report happiness. This study showed hardiness as being a protective factor against perceived stress and a facilitating factor for happiness in nurses. The findings could be important in training future nurses so that hardiness can be imparted, thereby giving them the ability to control their stress. © 2014 John Wiley & Sons Ltd.

Examination of cortisol and state anxiety at an academic setting with and without oral presentation.

PubMed

Merz, Christian Josef; Wolf, Oliver Tobias

2015-01-01

Holding oral presentations in a university course is perceived as stressful and can increase stress hormone concentrations and state anxiety. In such a naturalistic setting, further attention should be paid to the relationship between psychological and hormonal measures of acute stress, as well as women's intake of hormonal contraceptives as a potential moderating variable. In the present study, 76 healthy students gave saliva samples before and after their oral presentations in a university course as well as on a second, control day in the same course without giving an oral presentation. Anticipatory state anxiety was rated on both days. Cortisol concentrations as well as state anxiety were substantially higher on the presentation relative to the control day. During the oral presentation, an increase in cortisol concentrations was observed, whereas a decrease occurred on the control day. Nearly the same picture emerged for both variables when looking at men, women taking hormonal contraceptives and free-cycling women separately. A positive correlation was found between the change in anticipatory state anxiety in the presentation compared to the control day and cortisol concentrations before and after the oral presentation. Concluding, oral presentations constitute a potent stressor and do not seem to be substantially different between men, free-cycling women and women taking hormonal contraceptives. Future studies may want to explore changes associated with specific menstrual cycle phases and with specific hormonal contraceptives.

Employee occupational stress in banking.

PubMed

Michailidis, Maria; Georgiou, Yiota

2005-01-01

Occupational stress literature emphasizes the importance of assessment and management of work related stress. The recognition of the harmful physical and psychological effects of stress on both individuals and organizations is widely studied in many parts of the world. However, in other regions such research is only at the introductory stages. The present study examines occupational stress of employees in the banking sector. A sample of 60 bank employees at different organizational levels and educational backgrounds was used. Data collection utilized the Occupational Stress Indicator (OSI). Results of data analysis provided evidence that employees' educational levels affect the degree of stress they experience in various ways. Bank employees cannot afford the time to relax and "wind down" when they are faced with work variety, discrimination, favoritism, delegation and conflicting tasks. The study also shows the degree to which some employees tend to bring work-related problems home (and take family problems to work) depends on their educational background, the strength of the employees' family support, and the amount of time available for them to relax. Finally, the drinking habits (alcohol) of the employees were found to play a significant role in determining the levels of occupational stress.

Comparative inter-institutional study of stress among dentists.

PubMed

Pozos-Radillo, Blanca E; Galván-Ramírez, Ma Luz; Pando, Manuel; Carrión, Ma De los Angeles; González, Guillermo J

2010-01-01

Dentistry is considered to be a stressful profession due to different factors caused by work, representing a threat to dentists'health. The objectives of this work were to identify and compare chronic stress in dentists among the different health institutions and the association of stress with risk factors. The study in question is observational, transversal and comparative; 256 dentists were included, distributed among five public health institutions in the city of Guadalajara, Jalisco, Mexico, namely: the Mexican Institute of Social Security (IMSS), the Ministry of Health (SS), the Integral Development of the Family (DIF), the Social Security Services Institute for the Workers (ISSSTE) and the University of Guadalajara (U. de G) Data were obtained by means of the census technique. Stress was identified using the Stress Symptoms Inventory and the statistical analysis was performed using the Odds Ratio (O.R.) and the chi-square statistic. From the total population studied, 219 subjects presented high levels of chronic stress and 37, low levels. In the results of comparative analysis, significant differences were found between IMSS and U. de G and likewise between IMSS and SS. However, in the analysis of association, only U. de G was found to be associated with the high level of chronic stress.

Circulatory shear flow alters the viability and proliferation of circulating colon cancer cells

NASA Astrophysics Data System (ADS)

Fan, Rong; Emery, Travis; Zhang, Yongguo; Xia, Yuxuan; Sun, Jun; Wan, Jiandi

2016-06-01

During cancer metastasis, circulating tumor cells constantly experience hemodynamic shear stress in the circulation. Cellular responses to shear stress including cell viability and proliferation thus play critical roles in cancer metastasis. Here, we developed a microfluidic approach to establish a circulatory microenvironment and studied circulating human colon cancer HCT116 cells in response to a variety of magnitude of shear stress and circulating time. Our results showed that cell viability decreased with the increase of circulating time, but increased with the magnitude of wall shear stress. Proliferation of cells survived from circulation could be maintained when physiologically relevant wall shear stresses were applied. High wall shear stress (60.5 dyne/cm2), however, led to decreased cell proliferation at long circulating time (1 h). We further showed that the expression levels of β-catenin and c-myc, proliferation regulators, were significantly enhanced by increasing wall shear stress. The presented study provides a new insight to the roles of circulatory shear stress in cellular responses of circulating tumor cells in a physiologically relevant model, and thus will be of interest for the study of cancer cell mechanosensing and cancer metastasis.

General self-efficacy and posttraumatic stress after a natural disaster: a longitudinal study.

PubMed

Nygaard, Egil; Hussain, Ajmal; Siqveland, Johan; Heir, Trond

2016-04-06

Self-efficacy may be an important factor in individuals' recovery from posttraumatic stress reactions after a natural disaster. However, few longitudinal studies have investigated whether self-efficacy predicts the course of posttraumatic recovery beyond lower initial levels of distress. The purpose of the present study was to investigate whether general self-efficacy is related to recovery from posttraumatic stress reactions from a longitudinal perspective. A total of 617 Norwegians exposed to the 2004 Southeast Asian tsunami completed self-report questionnaires measuring their level of disaster exposure and general self-efficacy at 6 months and posttraumatic stress reactions 6 months and 2 years post-disaster. Predictors of changes in posttraumatic stress reactions were analyzed with multivariate mixed effects models. Self-efficacy at 6 months post-disaster was unrelated to trauma exposure and inversely related to posttraumatic stress reactions at 6 months and 2 years post-disaster. However, self-efficacy was not related to recovery from posttraumatic stress reactions between 6 months and 2 years post-disaster. In conclusion, general self-efficacy is related to lower levels of posttraumatic stress reactions in the first months after a disaster but does not appear to be related to improved recovery rates over the longer term.

Work stress, family stress and asthma: a cross-sectional study among women in China.

PubMed

Loerbroks, Adrian; Ding, Hui; Han, Wei; Wang, Hong; Wu, Jiang-Ping; Yang, Liu; Angerer, Peter; Li, Jian

2017-05-01

Research addressing links of work stress or family stress with asthma is constrained by (1) inconsistent evidence, (2) failure to consider the combined exposure to work stress and family stress, and (3) its primary focus on Western study populations. We aimed to address these knowledge gaps. We used cross-sectional data collected in 2015 among 7816 women from five professional groups in five Chinese cities. Work stress was measured by the 10-item effort-reward imbalance (ERI) questionnaire. Family stress was assessed by a psychometrically evaluated instrument comprising five items on, e.g., familial conflicts or domestic workload. Asthma was operationalized by self-reports of a physician diagnosis. Associations were examined by multivariable logistic regression estimating odds ratios (ORs) and 95% confidence intervals (CIs). Both high work stress (i.e., ERI score >1) and high family stress (i.e., score above the median) were associated with asthma (OR 1.66, 95% CI 1.22-2.27 and OR 1.48, 95% CI 1.10-1.99, respectively). Women with combined exposure (versus none) had somewhat higher odds of asthma (OR 2.13, 95% CI 1.42-3.19) than those with sole exposure to either work stress (OR 1.89, 95% CI 1.20-2.96) or family stress (OR 1.71, 95% CI 1.03-2.84). Interaction terms were significant for continuous variables (p = 0.046), but not for dichotomized variables (p = 0.199). The present study suggests that both work stress and family stress are positively associated with asthma in women in China. Further, the combined exposure may be associated with a further excess of asthma occurrence. Longitudinal studies are needed to confirm our findings and to explore potential temporal relationships.

Impact of Chronic Stress Protocols in Learning and Memory in Rodents: Systematic Review and Meta-Analysis

PubMed Central

Moreira, Pedro Silva; Almeida, Pedro R; Leite-Almeida, Hugo; Sousa, Nuno; Costa, Patrício

2016-01-01

The idea that maladaptive stress impairs cognitive function has been a cornerstone of decades in basic and clinical research. However, disparate findings have reinforced the need to aggregate results from multiple sources in order to confirm the validity of such statement. In this work, a systematic review and meta-analyses were performed to aggregate results from rodent studies investigating the impact of chronic stress on learning and memory. Results obtained from the included studies revealed a significant effect of stress on global cognitive performance. In addition, stressed rodents presented worse consolidation of learned memories, although no significantly differences between groups at the acquisition phase were found. Despite the methodological heterogeneity across studies, these effects were independent of the type of stress, animals’ strains or age. However, our findings suggest that stress yields a more detrimental effect on spatial navigation tests’ performance. Surprisingly, the vast majority of the selected studies in this field did not report appropriate statistics and were excluded from the quantitative analysis. We have therefore purposed a set of guidelines termed PROBE (Preferred Reporting Orientations for Behavioral Experiments) to promote an adequate reporting of behavioral experiments. PMID:27662580

Selective attention as a protagonist in contemporary workplace stress: implications for the interruption age.

PubMed

Tams, Stefan; Thatcher, Jason; Grover, Varun; Pak, Richard

2015-01-01

The ubiquity of instant messages and email notifications in contemporary work environments has opened a Pandora's Box. This box is filled with countless interruptions coming from laptops, smartphones, and other devices, all of which constantly call for employees' attention. In this interruption era, workplace stress is a pervasive problem. To examine this problem, the present study hypothesizes that the three-way interaction among the frequency with which interrupting stimuli appear, their salience, and employees' deficits in inhibiting attentional responses to them impacts mental workload perceptions, ultimately leading to stress. The study, further, probes a related form of self-efficacy as a potential suppressor of interruption-based stress. The study used a 2 (low vs. high frequency) × 2 (low vs. high salience) mixed model design. The 128 subjects completed a test of their inhibitory deficits and rated their mental workload perceptions and experiences of stress following a computer-based task. Inhibitory deficits and increased interruption salience can alter the perception of mental workload in contemporary work environments for the worse, but interruption self-efficacy can help offset any resulting interruption-based stress. This study extends the literatures on work interruptions as well as on stress and coping in the workplace.

Present-day stress state in the Outokumpu deep drill hole, Finland

NASA Astrophysics Data System (ADS)

Pierdominici, Simona; Ask, Maria; Kukkonen, Ilmo; Kueck, Jochem

2017-04-01

This study aims to investigate the present-day stress field in the Outokumpu area, eastern Finland, using interpretation of borehole failure on acoustic image logs in a 2516 m deep hole. Two main objectives of this study are: i. to constrain the orientation of maximum horizontal stress by mapping the occurrence of stress-induced deformation features using two sets of borehole televiewer data, which were collected in 2006 and 2011; and ii. to investigate whether any time dependent deformation of the borehole wall has occurred (creep). The Outokumpu deep hole was drilled during 2004-2005 to study deep structures and seismic reflectors within the Outokumpu formation and conducted within the International Continental Scientific Drilling Program (ICDP). The hole was continuously core-drilled into Paleoproterozoic formation of metasediments, ophiolite-derived altered ultrabasic rocks and pegmatitic granite. In 2006 and 2011 two downhole logging campaigns were performed by the Operational Support Group of ICDP to acquire a set of geophysical data. Here we focus on a specific downhole logging measurement, the acoustic borehole televiewer (BHTV), to determine the present-day stress field in the Outokumpu area. We constrain the orientation and magnitude of in situ stress tensor based on borehole wall failures detected along a 2516 m deep hole. Horizontal stress orientation was determined by interpreting borehole breakouts (BBs) and drilling-induced tensile fractures (DIFs) from BHTV logs. BBs are stress-induced enlargements of the borehole cross section and occur in two opposite zones at angles around the borehole where the wellbore stress concentration (hoop stress) exceeds the value required to cause compressive failure of intact rock. DIFs are caused by tensile failure of the borehole wall and form at two opposite spots on the borehole where the stress concentration is lower than the tensile strength of the rock. This occurs at angles 90° apart from the center of the breakout zone. Acoustic imaging logs provide a high-resolution oriented picture of the borehole wall that allows for the direct observation of BBs, which appear as two almost vertical swaths on the borehole image separated by 180°. BBs show poor sonic reflectivity and long travel times due to the many small brittle fractures and the resulting spalling. DIFs appear as two narrow stripes of low reflectivity separated by 180° and typically sub-parallel or slightly inclined to the borehole axis. The analysis of these images shows a distinct compressive failure area consistent with major geological and tectonic lineaments of the area. Deviations from this trend reflect local structural perturbations. Additionally, the 2006 and 2011 dataset are used to compare the changes of breakout geometry and to quantify the growth of the breakouts in this time span from differences in width, length and depth to estimate the magnitude of the horizontal stress tensors. Our study contributes to understand the structure of the shallow crust in the Outokumpu area by defining the current stress field. Furthermore, a detailed understanding of the regional stress field is a fundamental contribution in several research areas such as exploration and exploitation of underground resources, and geothermal reservoir studies.

Competency to Study and Learn in Stressful Contests: Fundamentals of the "e-Coping with Academic Stress"™ Utility

ERIC Educational Resources Information Center

de la Fuente, Jesús; López, Mireia; Zapata, Lucía; Martínez-Vicente, Jose Manuel; Vera, Manuel Mariano; Solinas, Giulliana; Fadda, Salvatore

2014-01-01

There has been growing research interest in achievement emotions in university teaching-learning processes in recent years. While their importance has been firmly established, there continues to be a need for assessment and intervention models. The objective of this report is to present the "Competency Model for Studying, Learning and…

Locus of Control Predicts Cortisol Reactivity and Speech Performance in Response to Acute Stress in Undergraduate Students

ERIC Educational Resources Information Center

Szabo, Yvette Z.; Chang, Andrew; Chancellor-Freeland, Cheryl

2015-01-01

Previous studies have found that an individual's perception of control in a situation (Locus of Control; LOC) can serve as a protective factor that has physiological and psychological benefits. The present study examines LOC in an acute stress paradigm to examine the relationship between LOC and hypothalamic-pituitary-adrenal axis functioning as…

Still Stressed but Feeling Better: Well-Being in Autism Spectrum Disorder Families as Children Become Adults

ERIC Educational Resources Information Center

Pozo, Pilar; Sarriá, Encarnación

2015-01-01

The transition to adulthood and adulthood itself have been identified as times of stress for parents of individuals with autism spectrum disorder. Longitudinal studies, however, show improvements in the well-being of mothers of adolescents and young adults with autism spectrum disorder. This article presents a cross-sectional study of 102 Spanish…

Methodological Aspects Regarding The Organizational Stress Analysis

NASA Astrophysics Data System (ADS)

Irimie, Sabina; Pricope (Muntean), Luminiţa Doina; Pricope, Sorin; Irimie, Sabin Ioan

2015-07-01

This work presents a research of methodology in occupational stress analyse in the educational field, as a part of a larger study. The objectives of the work are in finding accents in existence of significant relations between stressors and effects, meaning the differences between the indicators of occupational stress to teaching staff in primary and gymnasium school, taking notice of each specific condition: the institution as an entity, the working community, the discipline he/she is teaching others, the geographic and administrative district (urban/rural) and the quantification of stress level.

Prospective study on suicidal ideation among Japanese undergraduate students: correlation with stressful life events, depression, and depressogenic cognitive patterns.

PubMed

Hiramura, Hidetoshi; Shono, Masahiro; Tanaka, Nao; Nagata, Toshiaki; Kitamura, Toshinori

2008-01-01

The present study examines the effects of stressful life events, depression, and depressogenic cognitive patterns on suicidal ideation in 500 Japanese undergraduate students. The above factors were assessed at baseline (T1) and two weeks later (T3). At T1, structural equation modeling confirmed that (1) cognitive patterns and depression, but not stressful life events, influence suicidal ideation, and (2) cognitive patterns also influence suicidal ideation through depression. These findings were confirmed in a longitudinal analysis. The results suggest that the effects of stressful life events on suicidal ideation are indirect and are mediated by depressogenic cognitive styles and depressed mood.

Clinical experimental stress studies: methods and assessment.

PubMed

Bali, Anjana; Jaggi, Amteshwar Singh

2015-01-01

Stress is a state of threatened homeostasis during which a variety of adaptive processes are activated to produce physiological and behavioral changes. Stress induction methods are pivotal for understanding these physiological or pathophysiological changes in the body in response to stress. Furthermore, these methods are also important for the development of novel pharmacological agents for stress management. The well-described methods to induce stress in humans include the cold pressor test, Trier Social Stress Test, Montreal Imaging Stress Task, Maastricht Acute Stress Test, CO2 challenge test, Stroop test, Paced Auditory Serial Addition Task, noise stress, and Mannheim Multicomponent Stress Test. Stress assessment in humans is done by measuring biochemical markers such as cortisol, cortisol awakening response, dexamethasone suppression test, salivary α-amylase, plasma/urinary norepinephrine, norepinephrine spillover rate, and interleukins. Physiological and behavioral changes such as galvanic skin response, heart rate variability, pupil size, and muscle and/or skin sympathetic nerve activity (microneurography) and cardiovascular parameters such as heart rate, blood pressure, and self-reported anxiety are also monitored to assess stress response. This present review describes these commonly employed methods to induce stress in humans along with stress assessment methods.

The Effects of Discrimination Experience on Life Satisfaction of North Korean Refugees: Mediating Effect of Stress

PubMed Central

Noh, Jin-Won; Park, Hyunchun; Kim, Minji; Kwon, Young Dae; Kim, Jin-Seok

2018-01-01

Objective This study investigated the mediation effect of stress between the experience of discrimination and life satisfaction among North Korean refugees who resettled in South Korea. The findings of the current study provide empirical evidence for the need of social interventions to mitigate adverse effects of stress on North Korean refugees who are subject to social discrimination on a daily basis. Methods In this study, we included 500 subjects among 2,138 North Korean refugees who took refuge in South Korea in 2007. The interview started from April 6th 2009 and finished on May 25th 2009. We conducted moderator effect analysis with Path analysis was conducted because we confirm the experience of discrimination was affected by life satisfaction and stress can affected life satisfaction as a moderator. Results The experience of discrimination significantly affects stress and stress significantly affects life satisfaction. However, the experience of discrimination was not directly related to life satisfaction. The more stress the study respondents experienced, the lower the life satisfaction they reported. Conclusion The present finding suggests that the effects of discriminating experiences on the life satisfaction of North Korean refugees in South Korea were mediated by their own perceived stress. PMID:29422925

Endoplasmic reticulum stress contributes to acetylcholine receptor degradation by promoting endocytosis in skeletal muscle cells.

PubMed

Du, Ailian; Huang, Shiqian; Zhao, Xiaonan; Zhang, Yun; Zhu, Lixun; Ding, Ji; Xu, Congfeng

2016-01-15

After binding by acetylcholine released from a motor neuron, a nicotinic acetylcholine receptor at the neuromuscular junction produces a localized end-plate potential, which leads to muscle contraction. Improper turnover and renewal of acetylcholine receptors contributes to the pathogenesis of myasthenia gravis. In the present study, we demonstrate that endoplasmic reticulum (ER) stress contributes to acetylcholine receptor degradation in C2C12 myocytes. We further show that ER stress promotes acetylcholine receptor endocytosis and lysosomal degradation, which was dampened by blocking endocytosis or treating with lysosome inhibitor. Knockdown of ER stress proteins inhibited acetylcholine receptor endocytosis and degradation, while rescue assay restored its endocytosis and degradation, confirming the effects of ER stress on promoting endocytosis-mediated degradation of junction acetylcholine receptors. Thus, our studies identify ER stress as a factor promoting acetylcholine receptor degradation through accelerating endocytosis in muscle cells. Blocking ER stress and/or endocytosis might provide a novel therapeutic approach for myasthenia gravis. Copyright © 2015 Elsevier B.V. All rights reserved.

Psychosocial stress but not exercise increases cortisol and reduces state anxiety levels in school classes - results from a stressor applicable in large group settings.

PubMed

Wegner, Mirko; Müller-Alcazar, Anett; Jäger, Anika; Machado, Sergio; Arias-Carrión, Oscar; Budde, Henning

2014-01-01

Both, psychosocial stress and exercise in the past have been used as stressors to elevate saliva cortisol and change state anxiety levels. In the present study, high-school students at the age of 14 were randomly assigned to three experimental groups: (1) an exercise group (n = 18), that was running 15 minutes at a medium intensity level of 65-75% HRmax, (2) a psychosocial stress group (n = 19), and (3) a control group (n = 18). The psychosocial stress was induced to the students by completing a standardized intelligence test under the assumption that their IQ scores would be made public in class. Results display that only psychosocial stress but not exercise was able to significantly increase cortisol levels but decreased cognitive state anxiety in adolescents. The psychosocial stress protocol applied here is proposed for use in future stress studies with children or adolescents in group settings, e.g., in school.

Relationships among grit, academic performance, perceived academic failure, and stress in associate degree students.

PubMed

Lee, Wincy Wing Sze

2017-10-01

The present study examined the relationships among grit, academic performance, perceived academic failure, and stress levels of Hong Kong associate degree students using path analysis. Three hundred and forty-five students from a community college in Hong Kong voluntarily participated in the study. They completed a questionnaire that measured their grit (operationalized as interest and perseverance) and stress levels. The students also provided their actual academic performance and evaluated their perception of their academic performance as a success or a failure. The results of the path analysis showed that interest and perseverance were negatively associated with stress, and only perceived academic failure was positively associated with stress. These findings suggest that psychological appraisal and resources are more important antecedents of stress than objective negative events. Therefore, fostering students' psychological resilience may alleviate the stress experienced by associate degree students or college students in general. Copyright © 2017 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Evaluation and Adaption of the Trier Inventory for Chronic Stress (TICS) for Assessment in Competitive Sports

PubMed Central

Sallen, Jeffrey; Hirschmann, Florian; Herrmann, Christian

2018-01-01

The demands of a career in competitive sports can lead to chronic stress perception among athletes if there is a non-conformity of requirements and available coping resources. The Trier Inventory for Chronic Stress (TICS) (Schulz et al., 2004) is said to be thoroughly validated. Nevertheless, it has not yet been subjected to a confirmatory factor analysis. The present study aims (1) to evaluate the factorial validity of the TICS within the context of competitive sports and (2) to adapt a short version (TICS-36). The total sample consisted of 564 athletes (age in years: M = 19.1, SD = 3.70). The factor structure of the original TICS did not adequately fit the present data, whereas the short version presented a satisfactory fit. The results indicate that the TICS-36 is an economical instrument for gathering interpretable information about chronic stress. For assessment in competitive sports with TICS-36, we generated overall and gender-specific norm values. PMID:29593611

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

PubMed

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' reports, parental mindfulness was a mediator between child behavior problems and parental stress. The more the parents reported that their children had behavior problems, the less they reported being mindful, which in turn the more stressful they were. However, when child behavior problems were measured by teachers' reports, parental mindfulness was a moderator instead, moderating the association between child behavior problems and parental stress. The association was ameliorated when parents reported high levels of mindfulness. These findings reveal another possible role of mindfulness and shed light on the support for parents of children with ID. Copyright © 2017 Elsevier Ltd. All rights reserved.

Stress Survival Islet 2, Predominantly Present in Listeria monocytogenes Strains of Sequence Type 121, Is Involved in the Alkaline and Oxidative Stress Responses

PubMed Central

Harter, Eva; Wagner, Eva Maria; Zaiser, Andreas; Halecker, Sabrina; Wagner, Martin

2017-01-01

ABSTRACT The foodborne pathogen Listeria monocytogenes is able to survive a variety of stress conditions leading to the colonization of different niches like the food processing environment. This study focuses on the hypervariable genetic hot spot lmo0443 to lmo0449 haboring three inserts: the stress survival islet 1 (SSI-1), the single-gene insert LMOf2365_0481, and two homologous genes of the nonpathogenic species Listeria innocua: lin0464, coding for a putative transcriptional regulator, and lin0465, encoding an intracellular PfpI protease. Our prevalence study revealed a different distribution of the inserts between human and food-associated isolates. The lin0464-lin0465 insert was predominantly found in food-associated strains of sequence type 121 (ST121). Functional characterization of this insert showed that the putative PfpI protease Lin0465 is involved in alkaline and oxidative stress responses but not in acidic, gastric, heat, cold, osmotic, and antibiotic stresses. In parallel, deletion of lin0464 decreased survival under alkaline and oxidative stresses. The expression of both genes increased significantly under oxidative stress conditions independently of the alternative sigma factor σB. Furthermore, we showed that the expression of the protease gene lin0465 is regulated by the transcription factor lin0464 under stress conditions, suggesting that lin0464 and lin0465 form a functional unit. In conclusion, we identified a novel stress survival islet 2 (SSI-2), predominantly present in L. monocytogenes ST121 strains, beneficial for survival under alkaline and oxidative stresses, potentially supporting adaptation and persistence of L. monocytogenes in food processing environments. IMPORTANCE Listeria monocytogenes strains of ST121 are known to persist for months and even years in food processing environments, thereby increasing the risk of food contamination and listeriosis. However, the molecular mechanism underlying this remarkable niche-specific adaptation is still unknown. Here, we demonstrate that the genomic islet SSI-2, predominantly present in L. monocytogenes ST121 strains, is beneficial for survival under alkaline and oxidative stress conditions, which are routinely encountered in food processing environments. Our findings suggest that SSI-2 is part of a diverse set of molecular determinants contributing to niche-specific adaptation and persistence of L. monocytogenes ST121 strains in food processing environments. PMID:28625982

Stress Survival Islet 2, Predominantly Present in Listeria monocytogenes Strains of Sequence Type 121, Is Involved in the Alkaline and Oxidative Stress Responses.

PubMed

Harter, Eva; Wagner, Eva Maria; Zaiser, Andreas; Halecker, Sabrina; Wagner, Martin; Rychli, Kathrin

2017-08-15

The foodborne pathogen Listeria monocytogenes is able to survive a variety of stress conditions leading to the colonization of different niches like the food processing environment. This study focuses on the hypervariable genetic hot spot lmo0443 to lmo0449 haboring three inserts: the stress survival islet 1 (SSI-1), the single-gene insert LMOf2365_0481 , and two homologous genes of the nonpathogenic species Listeria innocua : lin0464 , coding for a putative transcriptional regulator, and lin0465 , encoding an intracellular PfpI protease. Our prevalence study revealed a different distribution of the inserts between human and food-associated isolates. The lin0464-lin0465 insert was predominantly found in food-associated strains of sequence type 121 (ST121). Functional characterization of this insert showed that the putative PfpI protease Lin0465 is involved in alkaline and oxidative stress responses but not in acidic, gastric, heat, cold, osmotic, and antibiotic stresses. In parallel, deletion of lin0464 decreased survival under alkaline and oxidative stresses. The expression of both genes increased significantly under oxidative stress conditions independently of the alternative sigma factor σ B Furthermore, we showed that the expression of the protease gene lin0465 is regulated by the transcription factor lin0464 under stress conditions, suggesting that lin0464 and lin0465 form a functional unit. In conclusion, we identified a novel stress survival islet 2 (SSI-2), predominantly present in L. monocytogenes ST121 strains, beneficial for survival under alkaline and oxidative stresses, potentially supporting adaptation and persistence of L. monocytogenes in food processing environments. IMPORTANCE Listeria monocytogenes strains of ST121 are known to persist for months and even years in food processing environments, thereby increasing the risk of food contamination and listeriosis. However, the molecular mechanism underlying this remarkable niche-specific adaptation is still unknown. Here, we demonstrate that the genomic islet SSI-2, predominantly present in L. monocytogenes ST121 strains, is beneficial for survival under alkaline and oxidative stress conditions, which are routinely encountered in food processing environments. Our findings suggest that SSI-2 is part of a diverse set of molecular determinants contributing to niche-specific adaptation and persistence of L. monocytogenes ST121 strains in food processing environments. Copyright © 2017 Harter et al.

Relationship at work as a cause of occupational stress: the case of academic women in Vietnam.

PubMed

Van Thanh, Le

2016-01-01

The present research paper aims to bring deeper understanding and insight to perceptions and experiences of occupational stress from relationships at work in the cultural context of Vietnam. The paper also examines differences in perceptions, experiences of occupational stress from this problem and makes a comparison with perspectives in other cultures. Grounded theory approach is used to study occupational stress by collecting data from in-depth interviews with 42 academic women employed at Vietnamese higher education institutions to understand the meaning, the nature and source of the occupational stress from relationships at work they experience and the impact of occupational stress on their lives. Cultural factors play an important role in occupational stress. Cultural factors such as power distance and hierarchy influence perception, experiences of occupational stress and the ways occupational stress is responded to. The Vietnamese context differs from other cultural contexts in the range of factors perceived as stressors for Vietnamese women. This paper is the first grounded theory study of occupational stress among women academics in Vietnam that determines that the natural of the relationship at work play an important role in how women understand and respond to occupational stress and supports the growing evidence that occupational stress is common, global but different in other cultures.

Prenatal stress perception and coping strategies: Insights from a longitudinal prospective pregnancy cohort.

PubMed

Goletzke, J; Kocalevent, R-D; Hansen, G; Rose, M; Becher, H; Hecher, K; Arck, P C; Diemert, A

2017-11-01

Prenatal distress has been linked to pregnancy complications and poor offspring's health, despite the fact that longitudinal assessments of various stress dimensions are still lacking. Hence, we aimed to assess perceived stress over the course of pregnancy. Moreover, we examined whether social support and coping styles are linked to prenatal stress trajectories. Data from 543 women participating in the PRINCE (Prenatal Identification of Children Health) study, a prospective population-based cohort study, was used for the present analyses. Once per trimester the women completed questionnaires regarding different psychometric measures, including the Perceived Stress Scale (PSS). Linear mixed regression models were used to examine perceived stress development longitudinally and to relate social support and coping styles to stress trajectories during pregnancy. A significant decrease of perceived stress was observed over the course of pregnancy. Stratifying the study sample according to parity, women delivering their first child had continuously lower perceived stress scores compared to women having already one or more children, and a significant decrease during pregnancy was exclusively observed in primiparous women. Both, positive coping strategies and higher perceived and received social support were independently associated with lower perceived stress, while evasive coping strategies were associated with higher levels of perceived stress. Our study reveals stress perception trajectories during pregnancies in primi- and multiparous women. Our findings underscore the need for intervention strategies aiming to improve social support and positive coping strategies especially in multiparous women in order to reduce the risks for adverse pregnancy outcomes. Copyright © 2017 Elsevier Inc. All rights reserved.

The overlooked relationship between motivational abilities and posttraumatic stress: a review

PubMed Central

Simmen-Janevska, Keti; Brandstätter, Veronika; Maercker, Andreas

2012-01-01

How does traumatic stress change the ability to motivate oneself to achieve certain goals? How do motivational abilities influence the development and course of trauma sequelae? Few studies have focused on motivational constructs within posttraumatic stress research. From a trauma research perspective, it can be hypothesized that traumatic stress may contribute to motivational dysfunction. The main goal of the present article is to fill this gap in research by reviewing and discussing the existing trauma literature in terms of motivation-related concepts, such as self-efficacy, locus of control, self-esteem, and self-control/impulsivity. Fifty-four studies were reviewed, 10 of which were longitudinal studies. Approximately 20% of the reviews assessed whether motivational concepts predict posttraumatic stress, whereas only 8% examined the reverse relationship. With the exception of a few studies, motivational constructs seem to predict posttraumatic stress over the life span. The strongest relationships were reported for self-efficacy, followed by locus of control and self-esteem and, lastly, impulsivity/self-control. Overall, the findings of this review indicate that there is a lack of research investigating motivational factors as outcome variables following traumatic experiences. Furthermore, the need for longitudinal studies and studies with older adults is noted. PMID:23125909

Proficiency in English sentence stress production by Cantonese speakers who speak English as a second language (ESL).

PubMed

Ng, Manwa L; Chen, Yang

2011-12-01

The present study examined English sentence stress produced by native Cantonese speakers who were speaking English as a second language (ESL). Cantonese ESL speakers' proficiency in English stress production as perceived by English-speaking listeners was also studied. Acoustical parameters associated with sentence stress including fundamental frequency (F0), vowel duration, and intensity were measured from the English sentences produced by 40 Cantonese ESL speakers. Data were compared with those obtained from 40 native speakers of American English. The speech samples were also judged by eight native listeners who were native speakers of American English for placement, degree, and naturalness of stress. Results showed that Cantonese ESL speakers were able to use F0, vowel duration, and intensity to differentiate sentence stress patterns. Yet, both female and male Cantonese ESL speakers exhibited consistently higher F0 in stressed words than English speakers. Overall, Cantonese ESL speakers were found to be proficient in using duration and intensity to signal sentence stress, in a way comparable with English speakers. In addition, F0 and intensity were found to correlate closely with perceptual judgement and the degree of stress with the naturalness of stress.

Influence of temperature on alkali stress adaptation in Listeria monocytogenes

USDA-ARS?s Scientific Manuscript database

Listeria monocytogenes cells may induce alkali stress adaptation when exposed to sublethal concentrations of alkaline cleaners and sanitizers that may be frequently used in the food processing environment. In the present study, the effect of temperature on the induction and the stability of such alk...

Simulating canopy temperature for modelling heat stress in cereals

USDA-ARS?s Scientific Manuscript database

Crop models must be improved to account for the large effects of heat stress effects on crop yields. To date, most approaches in crop models use air temperature despite evidence that crop canopy temperature better explains yield reductions associated with high temperature events. This study presents...

Genetic engineering of woody plants: current and future targets in a stressful environment.

PubMed

Osakabe, Yuriko; Kajita, Shinya; Osakabe, Keishi

2011-06-01

Abiotic stress is a major factor in limiting plant growth and productivity. Environmental degradation, such as drought and salinity stresses, will become more severe and widespread in the world. To overcome severe environmental stress, plant biotechnologies, such as genetic engineering in woody plants, need to be implemented. The adaptation of plants to environmental stress is controlled by cascades of molecular networks including cross-talk with other stress signaling mechanisms. The present review focuses on recent studies concerning genetic engineering in woody plants for the improvement of the abiotic stress responses. Furthermore, it highlights the recent advances in the understanding of molecular responses to stress. The review also summarizes the basis of a molecular mechanism for cell wall biosynthesis and the plant hormone responses to regulate tree growth and biomass in woody plants. This would facilitate better understanding of the control programs of biomass production under stressful conditions. Copyright © Physiologia Plantarum 2011.

Stress psychobiology in the context of addiction medicine: from drugs of abuse to behavioral addictions.

PubMed

Lemieux, Andrine; al'Absi, Mustafa

2016-01-01

In this chapter, we briefly review the basic biology of psychological stress and the stress response. We propose that psychological stress and the neurobiology of the stress response play in substance use initiation, maintenance, and relapse. The proposed mechanisms for this include, on the one hand, the complex interactions between biological mediators of the stress response and the dopaminergic reward system and, on the other hand, mediators of the stress response and other systems crucial in moderating key addiction-related behaviors such as endogenous opioids, the sympathetic-adrenal-medullary system, and endocannabinoids. Exciting new avenues of study including genomics, sex as a moderator of the stress response, and behavioral addictions (gambling, hypersexuality, dysfunctional internet use, and food as an addictive substance) are also briefly presented within the context of stress as a moderator of the addictive process. © 2016 Elsevier B.V. All rights reserved.

Poverty and involuntary engagement stress responses: examining the link to anxiety and aggression within low-income families.

PubMed

Wolff, Brian C; Santiago, Catherine DeCarlo; Wadsworth, Martha E

2009-05-01

Families living with the burdens of poverty-related stress are at risk for developing a range of psychopathology. The present study examines the year-long prospective relationships among poverty-related stress, involuntary engagement stress response (IESR) levels, and anxiety symptoms and aggression in an ethnically diverse sample of 98 families (300 individual family members) living at or below 150% of the US federal poverty line. Hierarchical Linear Modeling (HLM) moderator model analyses provided strong evidence that IESR levels moderated the influence of poverty-related stress on anxiety symptoms and provided mixed evidence for the same interaction effect on aggression. Higher IESR levels, a proxy for physiological stress reactivity, worsened the impact of stress on symptoms. Understanding how poverty-related stress and involuntary stress responses affect psychological functioning has implications for efforts to prevent or reduce psychopathology, particularly anxiety, among individuals and families living in poverty.

The Young and the Stressed: Stress, Impulse Control, and Health in College Students.

PubMed

Leppink, Eric W; Odlaug, Brian L; Lust, Katherine; Christenson, Gary; Grant, Jon E

2016-12-01

High levels of stress are common among young adults, particularly those enrolled in college. These degrees of stress have shown numerous deleterious effects across both academic and health variables. Findings regarding the role of stress in the presentation of impulse control disorders, particular among college students, are limited. This study examined potential associations between perceived stress, academic achievement, physical/mental health, and impulse control disorders in young adults. A total of 1805 students completed an online survey and were included in the analysis. Responders were grouped by their overall score on the Perceived Stress Scale into mild, moderate, or severe. Severe perceived stress was associated with worse academic achievement and worse physical health, as well as higher rates of psychiatric and impulsive disorders. These findings may suggest associations between stress and numerous aspects of mental/physical health in young adults, which could be an important consideration for individuals working with college students.

Sodic alkaline stress mitigation by exogenous melatonin in tomato needs nitric oxide as a downstream signal.

PubMed

Liu, Na; Gong, Biao; Jin, Zhiyong; Wang, Xiufeng; Wei, Min; Yang, Fengjuan; Li, Yan; Shi, Qinghua

2015-08-15

The present study was designed to determine the interactive effect of exogenous melatonin and nitric oxide (NO) on sodic alkaline stress mitigation in tomato seedlings. It was observed that exogenous melatonin treatment elevated NO levels in alkaline-stressed tomato roots. However, exogenous NO had little effects on melatonin levels. Importantly, melatonin-induced NO generation was accompanied by increased tolerance to alkaline stress. Chemical scavenging of NO reduced melatonin-induced alkaline stress tolerance and defense genes' expression. However, inhibition of melatonin biosynthesis had a little effect on NO-induced alkaline stress tolerance. These results strongly suggest that NO, acting as a downstream signal, is involved in the melatonin-induced tomato tolerance to alkaline stress. This process creates a new signaling pathway for improving stress tolerance in plant. Copyright © 2015 Elsevier GmbH. All rights reserved.

Parenting stress and anger expression as predictors of child abuse potential.

PubMed

Rodriguez, C M; Green, A J

1997-04-01

To explore one potential pathway to physical child abuse, the present investigation used hierarchical regression analysis using measures of parenting stress and anger expression to jointly predict child abuse potential. The Parenting Stress Index, State-Trait Anger Expression Inventory, and the Child Abuse Potential Inventory were administered to two different samples of New Zealand parents. As expected, both studies revealed parenting stress and anger expression and were individually positively correlated with child abuse potential: the major finding involved the strong point contribution of parenting stress and anger expression in predicting Child Abuse Potential Inventory scores. Application of findings for intervention and prevention are discussed.

Protein intake and stress levels in nurses and housewives of Pakistan

PubMed Central

Wattoo, Feroza Hamid; Memon, Muhammad Saleh; Memon, Allah Nawaz; Wattoo, Muhammad Hamid Sarwar; Asad, Muhammad Javaid; Siddique, Farzana

2011-01-01

Stress has many biological effects on human daily life. In the present study, dietary protein intake was correlated with the investigated stress levels of nurses and housewives of the targeted urban population. Age group ranged from 30 to 45 years and both the groups belonged to middle socioeconomic status. After calculations of environmental, psychological and physiological stresses, it was observed that the levels of stress in housewives were significantly higher than those of nurses. Recommended dietary allowances, RDA and actual protein intakes, API were also compared in both the groups. The found protein intake was less in housewives as compared to that of nurses. PMID:23961140

Protein intake and stress levels in nurses and housewives of Pakistan.

PubMed

Wattoo, Feroza Hamid; Memon, Muhammad Saleh; Memon, Allah Nawaz; Wattoo, Muhammad Hamid Sarwar; Asad, Muhammad Javaid; Siddique, Farzana

2011-07-01

Stress has many biological effects on human daily life. In the present study, dietary protein intake was correlated with the investigated stress levels of nurses and housewives of the targeted urban population. Age group ranged from 30 to 45 years and both the groups belonged to middle socioeconomic status. After calculations of environmental, psychological and physiological stresses, it was observed that the levels of stress in housewives were significantly higher than those of nurses. Recommended dietary allowances, RDA and actual protein intakes, API were also compared in both the groups. The found protein intake was less in housewives as compared to that of nurses.

The Inclusion of In-Plane Stresses in Delamination Criteria

NASA Technical Reports Server (NTRS)

Vizzini, Anthony J.; Fenske, Matthew T.

1998-01-01

A study of delamination is performed including strength of materials and fracture mechanics approaches with emphasis placed on methods of delamination prediction. Evidence is presented which supports the inclusion of the in-plane stresses in addition to the inter-laminar stress terms in delamination criteria. The delamination can be modeled as a resin rich region in between ply sets. The entire six component stress state in this resin layer is calculated through a finite element analysis and inputted into a new Modified Von Mises Delamination Criterion. This criterion builds onto previous criteria by including all six stress components. The MVMDC shows improved correlation to experimental data.

Berberine improves endothelial function by inhibiting endoplasmic reticulum stress in the carotid arteries of spontaneously hypertensive rats.

PubMed

Liu, Limei; Liu, Jian; Huang, Zhengxiang; Yu, Xiaoxing; Zhang, Xinyu; Dou, Dou; Huang, Yu

2015-03-20

Activation of endoplasmic reticulum (ER) stress in endothelial cells leads to increased oxidative stress and often results in cell death, which has been implicated in hypertension. The present study investigated the effects of berberine, a botanical alkaloid purified from Coptidis rhizoma, on ER stress in spontaneously hypertensive rats (SHRs) and the underling mechanism. Isolated carotid arteries from normotensive WKYs and SHRs were suspended in myograph for isometric force measurement. Protein phosphorylations and expressions were determined by Western blotting. Reactive oxygen species (ROS) level was measured by DHE staining. SHR carotid arteries exhibited exaggerated acetylcholine-triggered endothelium-dependent contractions (EDCs) and elevated ROS accumulation compared with WKY arteries. Moreover, Western blot analysis revealed the reduced AMPK phosphorylation, increased eIF2α phosphorylation, and elevated levels of ATF3, ATF6, XBP1 and COX-2 in SHR carotid arteries while these pathological alterations were reversed by 12 h-incubation with berberine. Furthermore, AMPK inhibitor compound C or dominant negative AMPK adenovirus inhibited the effects of berberine on above-mentioned marker proteins and EDCs. More importantly, ROS scavengers, tempol and tiron plus DETCA, or ER stress inhibitors, 4-PBA and TUCDA normalized the elevated levels of ROS and COX-2 expression, and attenuated EDCs in SHR arteries. Taken together, the present results suggest that berberine reduces EDCs likely through activating AMPK, thus inhibiting ER stress and subsequently scavenging ROS leading to COX-2 down-regulation in SHR carotid arteries. The present study thus provides additional insights into the vascular beneficial effects of berberine in hypertension. Copyright © 2015 Elsevier Inc. All rights reserved.

The Relationship between Personality, Sense of Efficacy, and Stress in Korean Teachers

PubMed Central

Park, Subin; Song, Yul-Mai; Ko, Guy-Nueo; Jhung, Kyungun; Ha, Kyooseob; Lee, Young-Ryeol

2016-01-01

Several studies have linked teachers' personality characteristics and sense of efficacy to stress. However, investigating the relationship between these three constructs in this context was limited. This study aims to investigate the relationship between personality, sense of efficacy and perceived stress among Korean teachers. A total of 137 teachers working in elementary, middle, and high schools located in Seoul, South Korea were recruited for the study. The participants were administered Temperament and Character Inventory, Teacher's Sense of Efficacy Scale (TSES), and Perceived Stress Scale. The TSES was negatively correlated with harm avoidance and positively correlated with persistence, self-directedness, cooperativeness, and self-transcendence. Perceived stress was positively correlated with harm avoidance and negatively correlated with persistence and self-directedness. The path analysis showed that harm avoidance directly predicted perceived stress (β=0.37, 95% CI=0.21–0.53, p=0.002), and self-directedness and persistence predicted one's sense of efficacy (β=0.18, 95% CI=0.01–0.39 and β=0.31, 95% CI=0.10–0.47), which predicted perceived stress (β=-0.21, 95% CI=-0.39 to -0.02). The results of the present study indicate that harm avoidance might be associated with stress-proneness, while persistence, self-directedness, and sense of efficacy might act as protective resources against stress in Korean teachers. PMID:27757136

Review article: do exercise and fitness protect against stress-induced health complaints? A review of the literature.

PubMed

Gerber, Markus; Pühse, Uwe

2009-11-01

Understanding how exercise influences health is important in designing public health interventions. At present, evidence suggests that there is a positive relationship between exercise and health. However, whether this relationship is partly due to the stress-moderating impact of exercise has been less frequently investigated although more and more people are taxed by stressful life circumstances. A comprehensive review of studies testing the potential of exercise as a stress-buffer was conducted (including literature from 1982 to 2008). The findings are based on a narrative review method. Specific criteria were taken into account to evaluate causality of the evidence. About half of the studies reported at least partly supportive results in the sense that people with high exercise levels exhibit less health problems when they encounter stress. The causality analyses show that stress-moderation effects were consistently found in different samples and with different methodological approaches. Although more support results from cross-sectional studies, exercise-based stress-buffer effects were also found in prospective, longitudinal and quasi-experimental investigations. This review underscores the relevance of exercise as a public health resource. Recommendations are provided for future research. More prospective and experimental studies are needed to provide insight into how much exercise is necessary to trigger stress-buffer effects. Furthermore, more information is warranted to conclude which sort of exercise has the strongest impact on the stress-illness-relationship.

The fibroblast expression of RANKL in CoCrMo-particle-induced osteolysis is mediated by ER stress and XBP1s.

PubMed

Wang, Zhenheng; Huang, Zhen; Gan, Jingjing; Liu, Naicheng; Zhou, Gang; Shi, Tongguo; Wang, Zhenzhen; Wang, Rui; Bao, Nirong; Guo, Ting; Chen, Jiangning; Zhang, Junfeng; Dong, Lei; Zhao, Jianning

2015-09-01

Particle-induced osteolysis is a major cause of aseptic loosening, which is the most common reason for total hip arthroplasty (THA) failure and revision surgery. Although existing studies suggest that synovial fibroblasts present in the interfacial membrane are important targets of wear particles during bone resorption, the interaction mechanisms between the particles and fibroblasts remains elusive. In the present study, we investigated the effect of ER stress induced by CoCrMo particles (CoPs) in fibroblasts, calvarial resorption animal models and aseptic loosening clinical samples and its role in the stimulation of the RANKL expression. Our study further demonstrated that CoPs could induce significant ER stress in fibroblasts. Blocking ER stress with a specific inhibitor dramatically reduced the particle-induced expression of RANKL in vitro and in vivo. Furthermore, in fibroblasts, downregulation of the expression of XBP1s, a signaling molecule of ER stress, significantly reduced the expression of RANKL induced by wear particles. Moreover, inhibition of ER stress or XBP1s both ameliorated the CoPs-induced osteolysis in animal models. Collectively, these results suggested that in particle-induced osteolysis, CoPs could stimulate fibroblasts to secret RANKL through ER stress and the signaling molecule XBP1s. Therefore, downregulating ER stress or the signaling molecule XBP1s of fibroblasts represents a potential therapeutic approach for treating particle-induced peri-implant osteolysis. For the first time, our study demonstrated that ER stress mediated the induction of RANKL expression by CoPs in fibroblasts and promoted particle-induced osteolysis. Furthermore, the upregulation of RANKL by CoPs in fibroblasts was mediated by the ER stress signaling molecule XBP1s. Both blocking ER stress and inhibiting the protein XBP1s by specific inhibitors resulted in downregulation of the expression of RANKL and amelioration of osteolysis induced by the implanted particles. Collectively, these findings suggest a possible mechanism underlying the RANKL expression induced by wear particles in fibroblasts, and downregulating ER stress and the XBP1s expression of fibroblasts represents a potential therapeutic approach for treating aseptic loosening. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Associations between stress and migraine and tension-type headache: results from a school-based study in adolescents from grammar schools in Germany.

PubMed

Milde-Busch, Astrid; Blaschek, Astrid; Heinen, Florian; Borggräfe, Ingo; Koerte, Inga; Straube, Andreas; Schankin, Christoph; von Kries, Rüdiger

2011-05-01

Stress is considered the major contributor to migraine and tension-type headache in adolescents. Previous studies have focused on general stressors, whereas the aim of the present study was to investigate associations between individuals' stressful experiences and different types of headache. Adolescents from 10th and 11th grades of grammar schools filled in questionnaires. Stressful experiences were measured with the Trier Inventory of Chronic Stress. Type of headache was classified according to the International Classification of Headache Disorders. Linear regressions, adjusted for sex and grade, were calculated to estimate differences in stress scores that can be attributed to migraine, tension-type headache or miscellaneous headache. A total of 1260 questionnaires were analysed. Tension-type headache, migraine and co-existing migraine plus tension-type headache were found in 48.7%, 10.2% and 19.8% of the participants. In subjects with migraine or co-existing migraine plus tension-type headache, high increases in stress scores were found in all investigated dimensions, whereas much weaker and inconsistent associations were found in subjects with tension-type headache only. The characteristic of migraine is more associated with stressful experiences than this is the case for tension-type headache. This suggests that adolescent migraine patients might especially benefit from behavioural interventions regarding stress.

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.

PubMed

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.

Corticotrophin-releasing hormone type 1 receptor gene (CRHR1) variants predict posttraumatic stress disorder onset and course in pediatric injury patients.

PubMed

Amstadter, Ananda B; Nugent, Nicole R; Yang, Bao-Zhu; Miller, Alisa; Siburian, Richie; Moorjani, Priya; Haddad, Stephen; Basu, Aditi; Fagerness, Jesen; Saxe, Glenn; Smoller, Jordan W; Koenen, Karestan C

2011-01-01

Posttraumatic stress disorder (PTSD) is a common and disabling anxiety disorder that may occur in the aftermath of exposure to potentially traumatic life events. PTSD is moderately heritable, but few specific molecular variants accounting for this heritability have been identified. Genes regulating the hypothalamic-pituitary-adrenal (HPA) axis, such as corticotrophin-releasing hormone type 1 receptor gene (CRHR1), have been implicated in traumatic-stress related phenotypes but have yet to be studied in relation to PTSD. The present study sought to examine the relation between 9 single nucleotide polymorphisms (SNPs) in the CRHR1 gene and posttraumatic stress symptoms in a prospective study of pediatric injury patients (n=103) who were first assessed in the acute aftermath of their injury at the hospital. Results indicated that multiple SNPs were associated with acute symptoms at a univariate level, and after correction for multiple testing, rs12944712 was significantly related to acute PTSD symptoms. Longitudinal latent growth curve analyses suggest that rs12944712 is also related to both acute symptom level and trajectory of symptoms over time. The present study adds support for the role of CRHR1 in the stress response following potentially traumatic event exposure in youth. It should be noted that the sample size in this study was small, and therefore statistical power was low; following, results from this study should be considered preliminary. Although results are not definitive, the findings from this study warrant future replication studies on how variation in this gene relates to response to traumatic event exposure in youth.

Co-Rumination Exacerbates Stress Generation among Adolescents with Depressive Symptoms.

PubMed

Rose, Amanda J; Glick, Gary C; Smith, Rhiannon L; Schwartz-Mette, Rebecca A; Borowski, Sarah K

2017-07-01

Through stress generation, individuals' own thoughts and behaviors can actually lead to increases in their experience of stress. Unfortunately, stress generation is especially common among individuals who are already suffering from elevated depressive symptoms. However, despite the acknowledgement that some individuals with depressive symptoms generate greater stress than others, few studies have identified specific factors that could exacerbate stress generation among individuals with depressive symptoms. The present study examines co-rumination as a factor that might exacerbate stress generation among adolescents with depressive symptoms using a short-term longitudinal design. Considering these processes among adolescents was critical given that many youth experience increases in depressive symptoms at this developmental stage and that co-rumination also becomes more common at adolescence. Participants were 628 adolescents (326 girls; 302 boys) who reported on their depressive symptoms, experiences of stress, and co-rumination with a best friend. Interpersonal stressors (peer and family stress) and non-interpersonal stressors (school and sports stress) were assessed. Consistent with past research, adolescents with depressive symptoms experienced greater interpersonal and non-interpersonal stress over time. Importantly, co-rumination interacted with both depressive symptoms and gender in predicting increases in peer stress. Depressive symptoms predicted the generation of peer stress only for girls who reported high levels of co-rumination with friends. Implications for protecting youth with depressive symptoms against stress generation are discussed.

Facebook Addiction Disorder (FAD) among German students-A longitudinal approach.

PubMed

Brailovskaia, Julia; Margraf, Jürgen

2017-01-01

The present study aimed to investigate Facebook Addiction Disorder (FAD) in a German student sample over a period of one year. While mean FAD level did not increase during the investigation period, a significant increase was shown in the number of participants reaching the critical cutoff score. FAD was significantly positively related to the personality trait narcissism and to negative mental health variables (depression, anxiety, and stress symptoms). Furthermore, FAD fully mediated the significant positive relationship between narcissism and stress symptoms, which demonstrates that narcissistic people can be specifically at risk to develop FAD. Present results give a first overview of FAD in Germany. Practical applications for future studies and limitations of present results are discussed.

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

PubMed

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.

The Impact of Interpersonal Discrimination and Stress on Health and Performance for Early Career STEM Academicians

PubMed Central

O’Brien, Katharine R.; McAbee, Samuel T.; Hebl, Michelle R.; Rodgers, John R.

2016-01-01

The present study examines the consequences of perceived interpersonal discrimination on stress, health, and performance in a sample of 210 science, technology, engineering, and mathematics (STEM) academicians. Using a path model, we test the relation that perceived interpersonal discrimination has on stress and the relation of stress to physical health maladies and on current and future performance. In so doing, we assess the link between discrimination and decrements in performance over time. Additionally, we test supervisor social support as a moderator of the discrimination–stress relation. Findings support relations between perceived interpersonal discrimination and stress, which in turn relates to declines in physical health and performance outcomes. Moreover, supervisory support is shown to mitigate the influence of interpersonal discrimination on stress in STEM academicians. PMID:27199848

Performance of two-lobe hole-entry hybrid journal bearing system under the combined influence of textured surface and couple stress lubricant

NASA Astrophysics Data System (ADS)

Khatri, Chandra B.; Sharma, Satish C.

2018-02-01

Textured surface in journal bearings is becoming an important area of investigation during the last few years. Surface textures have the shapes of micro-dimple with a small diameter and depth having order of magnitude of bearing clearance. This paper presents the influence of couple stress lubricant on the circular and non-circular hole-entry hybrid journal bearing system and reports the comparative study between the textured and non-textured circular/non-circular hybrid journal bearing system. The governing Reynolds equation has been modified for the couple stress lubricant flow in the clearance of bearing and journal. The FEM technique has been applied to solve the modified Reynolds equation together with restrictor flow equation. The numerically simulated results indicate that the influence of couple stress lubricant is significantly more in textured journal bearing than that of non-textured journal bearing. Further, it has been observed that the textured two-lobe (δ = 1.1) hybrid journal bearing lubricated with couple stress lubricant provides larger values of fluid film stiffness coefficients and stability threshold speed against other bearings studied in the present paper.

Protective effects of gallic acid against spinal cord injury-induced oxidative stress.

PubMed

Yang, Yong Hong; Wang, Zao; Zheng, Jie; Wang, Ran

2015-08-01

The present study aimed to investigate the role of gallic acid in oxidative stress induced during spinal cord injury (SCI). In order to measure oxidative stress, the levels of lipid peroxide, protein carbonyl, reactive oxygen species and nitrates/nitrites were determined. In addition, the antioxidant status during SCI injury and the protective role of gallic acid were investigated by determining glutathione levels as well as the activities of catalase, superoxide dismutase, glutathione peroxidase and glutathione-S-transferase. Adenosine triphophatase (ATPase) enzyme activities were determined to evaluate the role of gallic acid in SCI-induced deregulation of the activity of enzymes involved in ion homeostasis. The levels of inflammatory markers such as nuclear factor (NF)-κB and cycloxygenase (COX)-2 were determined by western blot analysis. Treatment with gallic acid was observed to significantly mitigate SCI-induced oxidative stress and the inflammatory response by reducing the oxidative stress, decreasing the expression of NF-κB and COX-2 as well as increasing the antioxidant status of cells. In addition, gallic acid modulated the activity of ATPase enzymes. Thus the present study indicated that gallic acid may have a role as a potent antioxidant and anti-inflammatory agent against SCI.

Rates and predictors of mental stress in Rwanda: investigating the impact of gender, persecution, readiness to reconcile and religiosity via a structural equation model.

PubMed

Heim, Lale; Schaal, Susanne

2014-01-01

As a consequence of the 1994 Rwandan genocide, prevalences of mental disorders are elevated in Rwanda. More knowledge about determinants of mental stress can help to improve mental health services and treatment in the east-central African country. The present study aimed to investigate actual rates of mental stress (posttraumatic stress disorder, syndromal depression and syndromal anxiety) in Rwanda and to examine if gender, persecution during the genocide, readiness to reconcile as well as importance given to religiosity and quality of religiosity are predictors of mental stress. The study comprised a community sample of N = 200 Rwandans from Rwanda's capital Kigali, who experienced the Rwandan genocide. By conducting structured interviews, ten local Master level psychologists examined types of potentially lifetime traumatic events, symptoms of posttraumatic stress disorder (PTSD), depression and anxiety, readiness to reconcile and religiosity. Applying non-recursive structural equation modeling (SEM), the associations between gender, persecution, readiness to reconcile, religiosity and mental stress were investigated. Respondents had experienced an average number of 11.38 types of potentially lifetime traumatic events. Of the total sample, 11% met diagnostic criteria for PTSD, 19% presented with syndromal depression and 23% with syndromal anxiety. Female sex, persecution and readiness to reconcile were significant predictors of mental stress. Twofold association was found between centrality of religion (which captures the importance given to religiosity) and mental stress, showing, that higher mental stress provokes a higher centrality and that higher centrality reduces mental stress. The variables positive and negative religious functioning (which determine the quality of religiosity) respectively had an indirect negative and positive effect on mental stress. Study results provide evidence that rates of mental stress are still elevated in Rwanda and that female sex, persecution, readiness to reconcile, centrality and religious functioning are predictors of mental stress. Seventeen years after the genocide, there remains a large gap between the need for and provision of mental health services in Rwanda. Results underline the importance of improving the respective infrastructure, with a focus on the requirements of women and persons, who were persecuted during the genocide. They further highlight that the consideration of readiness to reconcile, centrality and religious functioning in therapeutic interventions can aid mental health in Rwanda.

Perceived social stress and symptom severity among help-seeking adolescents with versus without clinical high-risk for psychosis.

PubMed

Millman, Zachary B; Pitts, Steven C; Thompson, Elizabeth; Kline, Emily R; Demro, Caroline; Weintraub, Marc J; DeVylder, Jordan E; Mittal, Vijay A; Reeves, Gloria M; Schiffman, Jason

2018-02-01

Research suggests that social stress exposure influences illness presentation and course among youth at clinical high-risk (CHR) for psychosis, though less is known about the extent to which self-reported perceptions of social stress relate to the severity of positive symptoms. Importantly, despite the notion that youth at CHR are especially susceptible to elevations in positive symptoms under conditions of stress, no study has examined this presumption relative to other psychiatric groups. Extending previous work demonstrating that perceived social stress was higher in a CHR group than in a clinical group of non-CHR, help-seeking controls, the current study aimed to: (1) examine whether perceived social stress is related to the severity of attenuated positive symptoms in the full sample (N=110); and (2) determine whether CHR status moderates the stress-symptom relation. Exploratory analyses examined relations of perceived social stress to negative, disorganized, and general symptoms. Greater perceptions of social stress were associated with more severe positive symptoms in the entire sample; however, although positive symptoms and perceived social stress were higher in the CHR group, the strength of this relation was statistically indistinguishable across groups. No differential effect of perceived social stress was observed for any symptom domain. Results provide some support for the diathesis-stress model of psychosis, while also suggesting that social stress and symptomatology are related independent of clinical vulnerability to psychosis. Future research would benefit from longitudinal studies of stress-symptom relations across CHR and help-seeking control groups. Copyright © 2017 Elsevier B.V. All rights reserved.

[BURNOUT SYNDROME AND STRESS OF NURSING STAFF IN A OURENSE HOSPITAL].

PubMed

Soto-Rodríguez, Anxela; Pérez-Fernandez, Ma Reyes

2015-02-01

Set up the stress prevalence and burnout syndrome in different units of nursing staff of the Complexo Hospitalario Universitario de Ourense (CHUOU) and analyse which factors cause it. It has been designed a transversal, descriptive study by performing three assessment instruments: questionnaire of social-demographic variables; Maslach Burnout Inventory (MBI), and Nursing Stress Scale (NSS), to a 117 nursing staff of CHUOU as population. The average age was 39.23 years old and 83.8% were women. The average scoring in the emotional exhaustion dimension was 24.44, in the component of depersonalization was 7.58, and in the personal accomplishment was 34.50. Moreover, 89.7% suffer stress related with work environment. The average score in the dimension of emotional exhaustion was 24.44, the depersonalization of 7.58 and the personal accomplishment of 34.50. The 89.7% suffered from work-related stress. Nursing staff present high burnout syndrome and stress. It has been observed a higher vulnerability to the syndrome from subjects with temporary contract and rotary shift. There has been statistically significant differences in young nursing staff and less career seniority, whom present hiqher stress levels.

The implications of tides on the Mimas ocean hypothesis

NASA Astrophysics Data System (ADS)

Rhoden, Alyssa Rose; Henning, Wade; Hurford, Terry A.; Patthoff, D. Alex; Tajeddine, Radwan

2017-02-01

We investigate whether a present-day global ocean within Mimas is compatible with the lack of tectonic activity on its surface by computing tidal stresses for ocean-bearing interior structure models derived from observed librations. We find that, for the suite of compatible rheological models, peak surface tidal stresses caused by Mimas' high eccentricity would range from a factor of 2 smaller to an order of magnitude larger than those on tidally active Europa. Thermal stresses from a freezing ocean, or a past higher eccentricity, would enhance present-day tidal stresses, exceeding the magnitudes associated with Europa's ubiquitous tidally driven fractures and, in some cases, the failure strength of ice in laboratory studies. Therefore, in order for Mimas to have an ocean, its ice shell cannot fail at the stress values implied for Europa. Furthermore, if Mimas' ocean is freezing out, the ice shell must also be able to withstand thermal stresses that could be an order of magnitude higher than the failure strength of laboratory ice samples. In light of these challenges, we consider an ocean-free Mimas to be the most straightforward model, best supported by our tidal stress analysis.

Multiple Reaction Monitoring Mode Based Liquid Chromatography-Mass Spectrometry Method for Simultaneous Quantification of Brassinolide and Other Plant Hormones Involved in Abiotic Stresses.

PubMed

Kasote, Deepak M; Ghosh, Ritesh; Chung, Jun Young; Kim, Jonggeun; Bae, Inhwan; Bae, Hanhong

2016-01-01

Plant hormones are the key regulators of adaptive stress response. Abiotic stresses such as drought and salt are known to affect the growth and productivity of plants. It is well known that the levels of plant hormones such as zeatin (ZA), abscisic acid (ABA), salicylic acid (SA), jasmonic acid (JA), and brassinolide (BR) fluctuate upon abiotic stress exposure. At present, there is not any single suitable liquid chromatography-mass spectrometry (LC-MS) method for simultaneous analysis of BR and other plant hormones involved in abiotic stresses. In the present study, we developed a simple, sensitive, and rapid method for simultaneous analysis of five major plant hormones, ZA, ABA, JA, SA, and BR, which are directly or indirectly involved in drought and salt stresses. The optimized extraction procedure was simple and easy to use for simultaneous measurement of these plant hormones in Arabidopsis thaliana. The developed method is highly reproducible and can be adapted for simultaneous measurement of changes in plant hormones (ZA, ABA, JA, SA, and BR) in response to abiotic stresses in plants like A. thaliana and tomato.

The Implications of Tides on the Mimas Ocean Hypothesis

NASA Technical Reports Server (NTRS)

Rhoden, Alyssa Rose; Henning, Wade; Hurford, Terry A.; Patthoff, D. Alex; Tajeddine, Radwan

2017-01-01

We investigate whether a present-day global ocean within Mimas is compatible with the lack of tectonic activity on its surface by computing tidal stresses for ocean-bearing interior structure models derived from observed librations. We find that, for the suite of compatible rheological models, peak surface tidal stresses caused by Mimas' high eccentricity would range from a factor of 2 smaller to an order of magnitude larger than those on tidally active Europa. Thermal stresses from a freezing ocean, or a past higher eccentricity, would enhance present-day tidal stresses, exceeding the magnitudes associated with Europa's ubiquitous tidally driven fractures and, in some cases, the failure strength of ice in laboratory studies. Therefore, in order for Mimas to have an ocean, its ice shell cannot fail at the stress values implied for Europa. Furthermore, if Mimas' ocean is freezing out, the ice shell must also be able to withstand thermal stresses that could be an order of magnitude higher than the failure strength of laboratory ice samples. In light of these challenges, we consider an ocean-free Mimas to be the most straightforward model, best supported by our tidal stress analysis.

Anticipatory stress associated with functional magnetic resonance imaging: Implications for psychosocial stress research.

PubMed

Gossett, Ethan W; Wheelock, Muriah D; Goodman, Adam M; Orem, Tyler R; Harnett, Nathaniel G; Wood, Kimberly H; Mrug, Sylvie; Granger, Douglas A; Knight, David C

2018-03-01

Stress tasks performed during functional magnetic resonance imaging (fMRI) elicit a relatively small cortisol response compared to stress tasks completed in a traditional behavioral laboratory, which may be due to apprehension of fMRI that elicits an anticipatory stress response. The present study investigated whether anticipatory stress is greater prior to research completed in an MRI environment than in a traditional behavioral laboratory. Anticipatory stress (indexed by cortisol) was greater prior to testing in the MRI environment than traditional behavioral laboratory. Furthermore, anticipation of fMRI elicited a cortisol response commensurate with the response to the stress task in the behavioral laboratory. However, in the MRI environment, post-stress cortisol was significantly lower than baseline cortisol. Taken together, these findings suggest the stress elicited by anticipation of fMRI may lead to acute elevations in cortisol prior to scanning, which may in turn disrupt the cortisol response to stress tasks performed during scanning. Copyright © 2018 Elsevier B.V. All rights reserved.

The Impact of Job Stress on Smoking and Quitting: Evidence from the HRS

PubMed Central

Ayyagari, Padmaja; Sindelar, Jody L.

2011-01-01

Job-related stress might affect smoking behavior because smoking may relieve stress and stress can make individuals more present-focused. Alternatively, individuals may both self-select into stressful jobs and choose to smoke based on unobserved factors. We use data from the Health and Retirement Study to examine how job stress affects the probability that smokers quit and the number of cigarettes smoked for current smokers. To address the potential endogeneity of job stress based on time invariant factors, we include individual fixed effects, which control for factors such as ability to handle stress. Occupational fixed effects are also included to control for occupational characteristics other than stress; time dummies control for the secular decline in smoking rates. Using a sample of people who smoked in the previous wave, we find that job stress is positively related to continuing to smoke among recent smokers. The results indicate that the key impact of stress is on the extensive margin of smoking, as opposed to the number of cigarettes smoked. PMID:21625286

Stress Distribution in Splinted and Unsplinted Implant-Supported Maxillary Overdentures: A 3D Finite Element Analysis.

PubMed

Geramy, Allahyar; Habibzadeh, Sareh

2018-02-01

This study was accomplished to assess the biomechanical state of splinting in implant-supported maxillary overdentures. Two models of maxillary overdentures were designed in SolidWorks 2011. The first model included 4 separate implants and ball abutments, whereas the second one included 4 splinted implants connected with a bar. Evaluation was performed in ANSYS Workbench software with 200 N load applied at the molar-premolar region, bilaterally. The maximum equivalent stress and strain (von Mises) was recorded and analyzed along a path between the implants in the crestal bone and the prosthetic attachments. First model presented higher values of strain in prosthetic attachment and higher values of von Mises stress in crestal bone. The second model presented higher stress concentration in the gingival tissue of premolar area (near the bar), whereas the peak stress values were reported within the most distal part of the soft tissue support of the prosthesis in the first model (unsplinted). Splinting maxillary overdentures implants is associated with significant lower stress levels in the surrounding bone tissue.

Comparative expression profile of NOD1/2 and certain acute inflammatory cytokines in thermal-stressed cell culture model of native and crossbred cattle

NASA Astrophysics Data System (ADS)

Bhanuprakash, V.; Singh, Umesh; Sengar, Gyanendra Singh; Raja, T. V.; Sajjanar, Basavraj; Alex, Rani; Kumar, Sushil; Alyethodi, R. R.; Kumar, Ashish; Sharma, Ankur; Kumar, Suresh; Bhusan, Bharat; Deb, Rajib

2017-05-01

Thermotolerance depends mainly on the health and immune status of the animals. The variation in the immune status of the animals may alter the level of tolerance of animals exposed to heat or cold stress. The present study was conducted to investigate the expression profile of two important nucleotide binding and oligomerization domain receptors (NLRs) (NOD1 and NOD2) and their central signalling molecule RIP2 gene during in vitro thermal-stressed bovine peripheral blood mononuclear cells (PBMCs) of native (Sahiwal) and crossbred (Sahiwal X HF) cattle. We also examined the differential expression profile of certain acute inflammatory cytokines in in vitro thermal-stressed PBMC culture among native and its crossbred counterparts. Results revealed that the expression profile of NOD1/2 positively correlates with the thermal stress, signalling molecule and cytokines. Present findings also highlighted that the expression patterns during thermal stress were comparatively superior among indigenous compared to crossbred cattle which may add references regarding the better immune adaptability of Zebu cattle.

Numerical simulation of present day tectonic stress across the Indian subcontinent

NASA Astrophysics Data System (ADS)

Yadav, R.; Tiwari, V. M.

2018-04-01

In situ measurements of maximum horizontal stress (S Hmax) in the Indian subcontinent are limited and do not present regional trends of intraplate stress orientation. The observed orientations of S Hmax vary considerably and often differ from the plate velocity direction. We have simulated orientation and magnitude of S Hmax through finite element modeling incorporating heterogeneities in elastic property of the Indian continent and plain stress approximation to understand the variability of S Hmax. Four different scenarios are tested in simulation: (1) homogeneous plate with fixed plate boundary (2) homogeneous plate with boundary forces (3) heterogeneous plate with fixed boundary (4) heterogeneous plate with boundary forces. The estimated orientation and magnitude of S Hmax with a heterogeneous plate with boundary forces in the Himalayan region and an eastern plate boundary comprising the Indo-Burmese arc and Andaman subduction zone are consistent with measured maximum horizontal stress. This study suggests that plate boundary force varies along the northern Indian plate margin and also provides a constraint on the intraplate stress field in the Indian subcontinent.