WorldWideScience

Sample records for stress reactivity scale

  1. The Perceived Stress Reactivity Scale: Measurement Invariance, Stability, and Validity in Three Countries

    Science.gov (United States)

    Schlotz, Wolff; Yim, Ilona S.; Zoccola, Peggy M.; Jansen, Lars; Schulz, Peter

    2011-01-01

    There is accumulating evidence that individual differences in stress reactivity contribute to the risk for stress-related disease. However, the assessment of stress reactivity remains challenging, and there is a relative lack of questionnaires reliably assessing this construct. We here present the Perceived Stress Reactivity Scale (PSRS), a…

  2. Stress Reactivity in Insomnia.

    Science.gov (United States)

    Gehrman, Philip R; Hall, Martica; Barilla, Holly; Buysse, Daniel; Perlis, Michael; Gooneratne, Nalaka; Ross, Richard J

    2016-01-01

    This study examined whether individuals with primary insomnia (PI) are more reactive to stress than good sleepers (GS). PI and GS (n = 20 per group), matched on gender and age, completed three nights of polysomnography. On the stress night, participants received a mild electric shock and were told they could receive additional shocks during the night. Saliva samples were obtained for analysis of cortisol and alpha amylase along with self-report and visual analog scales (VAS). There was very little evidence of increased stress on the stress night, compared to the baseline night. There was also no evidence of greater stress reactivity in the PI group for any sleep or for salivary measures. In the GS group, stress reactivity measured by VAS scales was positively associated with an increase in sleep latency in the experimental night on exploratory analyses. Individuals with PI did not show greater stress reactivity compared to GS.

  3. Stress reactivity and emotion in premenstrual syndrome

    Directory of Open Access Journals (Sweden)

    Liu Q

    2017-06-01

    Full Text Available Qing Liu,1 Yongshun Wang,2 Cornelis Hermanus van Heck,3 Wei Qiao4 1Department of Nuclear Medicine and Medical PET Center, The Second Hospital of Zhejiang University School of Medicine, Zhejiang University, Hangzhou, 2School of Physical Education and Sport, Huaqiao University, Xiamen, People’s Republic of China; 3DCC, Donders Institute for Neuroscience and Neurocognition, Arnhem, the Netherlands; 4Department of Physical Education, Xiamen Institute of Technology, Xiamen, People’s Republic of China Background: Hormone level fluctuation across the menstrual cycle causes women to experience negative emotions and also affects their mood regulation and stress sensitivity. However, the stress reactivity and emotional variations in women with premenstrual syndrome (PMS, who are especially sensitive to the variations in hormone cycles, have not been explained. Methods: The present study used an electroencephalogram (EEG stress evaluation test, a physiology stress evaluation test, and the positive affect and negative affect scale (PANAS to evaluate the stress reactivity pattern and emotional state of women with PMS. Results: The results showed that women with PMS had higher negative affect and lower positive affect compared with controls. Moreover, under stressful conditions, the women with PMS had a higher alpha activity and a lower respiration rate than the controls. The differences in stress reactivity and emotional states between women with PMS and controls were based on a covariant analysis with menstrual cycle (luteal and follicular phases as the covariate. Conclusion: The results demonstrated that, compared with controls, women suffering from PMS have a continuous abnormality in emotional state and stress reactivity, which was independent of the menstrual cycle. Keywords: premenstrual syndrome, stress reactivity, emotion, EEG stress evaluation test, physiology stress evaluation test

  4. Touch Attenuates Infants' Physiological Reactivity to Stress

    Science.gov (United States)

    Feldman, Ruth; Singer, Magi; Zagoory, Orna

    2010-01-01

    Animal studies demonstrate that maternal touch and contact regulate infant stress, and handling during periods of maternal deprivation attenuates the stress response. To measure the effects of touch on infant stress reactivity during simulated maternal deprivation, 53 dyads were tested in two paradigms: still-face (SF) and still-face with maternal…

  5. Physiological Stress Reactivity and Breast Cancer

    National Research Council Canada - National Science Library

    Wadhwa, Pathik

    2002-01-01

    .... Specifically, the present study is designed to conduct an investigation of the cross-sectional associations between indices of stress reactivity and psychological coping styles in women with breast...

  6. Physiological Stress Reactivity and Breast Cancer

    National Research Council Canada - National Science Library

    Wadhwa, Pathik

    2003-01-01

    .... Specifically, the present study is designed to conduct an investigation of the cross-sectional associations between indices of stress reactivity and psychological coping styles in women with breast...

  7. Physiological Stress Reactivity and Breast Cancer

    National Research Council Canada - National Science Library

    Wadhwa, Pathik

    2000-01-01

    .... Specifically, the present study is designed to conduct an investigation of the cross-sectional associations between indices of stress reactivity and psychological coping styles in women with breast...

  8. Physiological Stress Reactivity and Breast Cancer

    National Research Council Canada - National Science Library

    Wadhwa, Pathik

    2003-01-01

    ... cancer and matched healthy controls. The aims of the project are: (1) to quantify parameters of biological reactivity to a behavioral stress paradigm in women with and without breast cancer; (2) To examine...

  9. Physiological Stress Reactivity and Breast Cancer

    National Research Council Canada - National Science Library

    Wadhwa, Pathik

    2001-01-01

    ... cancer and matched healthy controls. The aims of the project are: (1) To quantify parameters of biological reactivity to a behavioral stress paradigm in women with and without breast cancer; (2...

  10. Physiological Stress Reactivity and Breast Cancer

    National Research Council Canada - National Science Library

    Wadhwa, Pathik

    2005-01-01

    ... cancer and matched healthy controls. The aims of the project are: (1) To quantify parameters of biological reactivity to a behavioral stress paradigm in women with and without breast cancer; (2...

  11. Blunted stress reactivity in chronic cannabis users.

    Science.gov (United States)

    Cuttler, Carrie; Spradlin, Alexander; Nusbaum, Amy T; Whitney, Paul; Hinson, John M; McLaughlin, Ryan J

    2017-08-01

    One of the most commonly cited reasons for chronic cannabis use is to cope with stress. Consistent with this, cannabis users have shown reduced emotional arousal and dampened stress reactivity in response to negative imagery. To our knowledge, the present study represents the first to examine the effects of an acute stress manipulation on subjective stress and salivary cortisol in chronic cannabis users compared to non-users. Forty cannabis users and 42 non-users were randomly assigned to complete either the stress or no stress conditions of the Maastricht Acute Stress Test (MAST). The stress condition of the MAST manipulates both physiological (placing hand in ice bath) and psychosocial stress (performing math under conditions of social evaluation). Participants gave baseline subjective stress ratings before, during, and after the stress manipulation. Cortisol was measured from saliva samples obtained before and after the stress manipulation. Further, cannabis cravings and symptoms of withdrawal were measured. Subjective stress ratings and cortisol levels were significantly higher in non-users in the stress condition relative to non-users in the no stress condition. In contrast, cannabis users demonstrated blunted stress reactivity; specifically, they showed no increase in cortisol and a significantly smaller increase in subjective stress ratings. The stress manipulation had no impact on cannabis users' self-reported cravings or withdrawal symptoms. Chronic cannabis use is associated with blunted stress reactivity. Future research is needed to determine whether this helps to confer resiliency or vulnerability to stress-related psychopathology as well as the mechanisms underlying this effect.

  12. Neighborhood disadvantage and adolescent stress reactivity

    Directory of Open Access Journals (Sweden)

    Daniel A. Hackman

    2012-10-01

    Full Text Available Lower socioeconomic status (SES is associated with higher levels of life stress, which in turn affect stress physiology. SES is related to basal cortisol and diurnal change, but it is not clear if SES is associated with cortisol reactivity to stress. To address this question, we examined the relationship between two indices of SES, parental education and concentrated neighborhood disadvantage, and the cortisol reactivity of African-American adolescents to a modified version of the Trier Social Stress Test. We found that concentrated disadvantage was associated with cortisol reactivity and this relationship was moderated by gender, such that higher concentrated disadvantage predicted higher cortisol reactivity and steeper recovery in boys but not in girls. Parental education, alone or as moderated by gender, did not predict reactivity or recovery, while neither education nor concentrated disadvantage predicted estimates of baseline cortisol. This finding is consistent with animal literature showing differential vulnerability, by gender, to the effects of adverse early experience on stress regulation and the differential effects of neighborhood disadvantage in adolescent males and females. This suggests that the mechanisms underlying SES differences in brain development and particularly reactivity to environmental stressors may vary across genders.

  13. Genetic influences on cardiovascular stress reactivity

    NARCIS (Netherlands)

    Wu, Ting; Snieder, Harold; de Geus, Eco

    Individual differences in the cardiovascular response to stress play a central role in the reactivity hypothesis linking frequent exposure to psychosocial stress to adverse outcomes in cardiovascular health. To assess the importance of genetic factors, a meta-analysis was performed on all published

  14. Cardiovascular Reactivity, Stress, and Physical Activity

    Directory of Open Access Journals (Sweden)

    Chun-Jung eHuang

    2013-11-01

    Full Text Available Psychological stress has been proposed as a major contributor to the progression of cardiovascular disease (CVD. Acute mental stress can activate the sympathetic-adrenal-medullary (SAM axis, eliciting the release of catecholamines (NE and EPI resulting in the elevation of heart rate (HR and blood pressure (BP. Combined stress (psychological and physical can exacerbate these cardiovascular responses, which may partially contribute to the elevated risk of CVD and increased proportionate mortality risks experienced by some occupations (e.g., firefighting and law enforcement. Studies have supported the benefits of physical activity on physiological and psychological health, including the cardiovascular response to acute stress. Aerobically trained individuals exhibit lower sympathetic nervous system (e.g., HR reactivity and enhanced cardiovascular efficiency (e.g., lower vascular reactivity and decreased recovery time in response to physical and/or psychological stress. In addition, resistance training has been demonstrated to attenuate cardiovascular responses and improve mental health. This review will examine stress-induced cardiovascular reactivity and plausible explanations for how exercise training and physical fitness (aerobic and resistance exercise can attenuate cardiovascular responses to stress. This enhanced functionality may facilitate a reduction in the incidence of stroke and myocardial infarction. Finally, this review will also address the interaction of obesity and physical activity on cardiovascular reactivity and CVD.

  15. Sexual Orientation Modulates Endocrine Stress Reactivity

    Science.gov (United States)

    Juster, Robert-Paul; Hatzenbuehler, Mark L.; Mendrek, Adrianna; Pfaus, James G.; Smith, Nathan Grant; Johnson, Philip Jai; Lefebvre-Louis, Jean-Philippe; Raymond, Catherine; Marin, Marie-France; Sindi, Shireen; Lupien, Sonia J.; Pruessner, Jens C.

    2015-01-01

    BACKGROUND Biological sex differences and sociocultural gender diversity influence endocrine stress reactivity. Although numerous studies have shown that men typically activate stronger stress responses than women when exposed to laboratory-based psychosocial stressors, it is unclear whether sexual orientation further modulates stress reactivity. Given that lesbian, gay, and bisexual (LGB) individuals frequently report heightened distress secondary to stigma-related stressors, we investigated whether cortisol stress reactivity differs between LGB individuals and heterosexual individuals in response to a well-validated psychosocial stressor. METHODS The study population comprised 87 healthy adults (mean age, 25 years) who were grouped according to their biological sex and their gendered sexual orientation: lesbian/bisexual women (n = 20), heterosexual women (n = 21), gay/bisexual men (n = 26), and heterosexual men (n = 20). Investigators collected 10 salivary cortisol samples throughout a 2-hour afternoon visit involving exposure to the Trier Social Stress Test modified to maximize between-sex differences. RESULTS Relative to heterosexual women, lesbian/bisexual women showed higher cortisol stress reactivity 40 min after exposure to the stressor. In contrast, gay/bisexual men displayed lower overall cortisol concentrations throughout testing compared with heterosexual men. Main findings were significant while adjusting for sex hormones (estradiol-to-progesterone ratio in women and testosterone in men), age, self-esteem, and disclosure status (whether LGB participants had completed their “coming out”). CONCLUSIONS Our results provide novel evidence for gender-based modulation of cortisol stress reactivity based on sexual orientation that goes beyond well-established between-sex differences. This study raises several important avenues for future research related to the physiologic functioning of LGB populations and gender diversity more broadly. PMID:25444167

  16. Sexual orientation modulates endocrine stress reactivity.

    Science.gov (United States)

    Juster, Robert-Paul; Hatzenbuehler, Mark L; Mendrek, Adrianna; Pfaus, James G; Smith, Nathan Grant; Johnson, Philip Jai; Lefebvre-Louis, Jean-Philippe; Raymond, Catherine; Marin, Marie-France; Sindi, Shireen; Lupien, Sonia J; Pruessner, Jens C

    2015-04-01

    Biological sex differences and sociocultural gender diversity influence endocrine stress reactivity. Although numerous studies have shown that men typically activate stronger stress responses than women when exposed to laboratory-based psychosocial stressors, it is unclear whether sexual orientation further modulates stress reactivity. Given that lesbian, gay, and bisexual (LGB) individuals frequently report heightened distress secondary to stigma-related stressors, we investigated whether cortisol stress reactivity differs between LGB individuals and heterosexual individuals in response to a well-validated psychosocial stressor. The study population comprised 87 healthy adults (mean age, 25 years) who were grouped according to their biological sex and their gendered sexual orientation: lesbian/bisexual women (n = 20), heterosexual women (n = 21), gay/bisexual men (n = 26), and heterosexual men (n = 20). Investigators collected 10 salivary cortisol samples throughout a 2-hour afternoon visit involving exposure to the Trier Social Stress Test modified to maximize between-sex differences. Relative to heterosexual women, lesbian/bisexual women showed higher cortisol stress reactivity 40 min after exposure to the stressor. In contrast, gay/bisexual men displayed lower overall cortisol concentrations throughout testing compared with heterosexual men. Main findings were significant while adjusting for sex hormones (estradiol-to-progesterone ratio in women and testosterone in men), age, self-esteem, and disclosure status (whether LGB participants had completed their "coming out"). Our results provide novel evidence for gender-based modulation of cortisol stress reactivity based on sexual orientation that goes beyond well-established between-sex differences. This study raises several important avenues for future research related to the physiologic functioning of LGB populations and gender diversity more broadly. Copyright © 2015 Society of Biological Psychiatry. Published

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

    Science.gov (United States)

    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.

  18. Stress Reactivity and Corticolimbic Response to Emotional Faces in Adolescents

    Science.gov (United States)

    Liu, Jie; Chaplin, Tara M.; Wang, Fei; Sinha, Rajita; Mayes, Linda C.; Blumberg, Hilary P.

    2012-01-01

    Objective: Adolescence is a critical period in the development of lifelong patterns of responding to stress. Understanding underpinnings of variations in stress reactivity in adolescents is important, as adolescents with altered stress reactivity are vulnerable to negative risk-taking behaviors including substance use, and have increased lifelong…

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

    Science.gov (United States)

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

    2014-08-01

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

  20. Good stress, bad stress and oxidative stress: insights from anticipatory cortisol reactivity.

    Science.gov (United States)

    Aschbacher, Kirstin; O'Donovan, Aoife; Wolkowitz, Owen M; Dhabhar, Firdaus S; Su, Yali; Epel, Elissa

    2013-09-01

    Chronic psychological stress appears to accelerate biological aging, and oxidative damage is an important potential mediator of this process. However, the mechanisms by which psychological stress promotes oxidative damage are poorly understood. This study investigates the theory that cortisol increases in response to an acutely stressful event have the potential to either enhance or undermine psychobiological resilience to oxidative damage, depending on the body's prior exposure to chronic psychological stress. In order to achieve a range of chronic stress exposure, forty-eight post-menopausal women were recruited in a case-control design that matched women caring for spouses with dementia (a chronic stress model) with similarly aged control women whose spouses were healthy. Participants completed a questionnaire assessing perceived stress over the previous month and provided fasting blood. Three markers of oxidative damage were assessed: 8-iso-prostaglandin F(2α) (IsoP), lipid peroxidation, 8-hydroxyguanosine (8-oxoG) and 8-hydroxy-2'-deoxyguanosine (8-OHdG), reflecting oxidative damage to RNA/DNA respectively. Within approximately one week, participants completed a standardized acute laboratory stress task while salivary cortisol responses were measured. The increase from 0 to 30 min was defined as "peak" cortisol reactivity, while the increase from 0 to 15 min was defined as "anticipatory" cortisol reactivity, representing a cortisol response that began while preparing for the stress task. Women under chronic stress had higher 8-oxoG, oxidative damage to RNA (pstress and elevated oxidative stress damage, but only among women under chronic stress. Consistent with this model, bootstrapped path analysis found significant indirect paths from perceived stress to 8-oxoG and IsoP (but not 8-OHdG) via anticipatory cortisol reactivity, showing the expected relations among chronically stressed participants (p≤.01) Intriguingly, among those with low chronic stress

  1. Cerebrovascular mental stress reactivity is impaired in hypertension

    Directory of Open Access Journals (Sweden)

    Naqvi Tasneem Z

    2009-07-01

    Full Text Available Abstract Background Brachial artery reactivity in response to shear stress is altered in subjects with hypertension. Since endothelial dysfunction is generalized, we hypothesized that carotid artery (CA reactivity would also be altered in hypertension. Purpose To compare (CA endothelium-dependent vasodilation in response to mental stress in normal and hypertensive subjects. Methods We evaluated CA reactivity to mental stress in 10 young healthy human volunteers (aged 23 ± 4 years, 20 older healthy volunteers (aged 49 ± 11 years and in 28 patients with essential hypertension (aged 51 ± 13 years. In 10 healthy volunteers and 12 hypertensive subjects, middle cerebral artery (MCA PW transcranial Doppler was performed before and 3 minutes after mental stress. Results Mental stress by Stroop color word conflict, math or anger recall tests caused CA vasodilation in young healthy subjects (0.61 ± 0.06 to 0.65 ± 0.07 cm, p Conclusion Mental stress produces CA vasodilation and is accompanied by an increase in CA and MCA blood flow in healthy subjects. This mental stress induced CA vasodilation and flow reserve is attenuated in subjects with hypertension and may reflect cerebral vascular endothelial dysfunction. Assessment of mental stress induced CA reactivity by ultrasound is a novel method for assessing the impact of hypertension on cerebrovascular endothelial function and blood flow reserve.

  2. Oxytocin receptor genetic variation relates to empathy and stress reactivity in humans.

    Science.gov (United States)

    Rodrigues, Sarina M; Saslow, Laura R; Garcia, Natalia; John, Oliver P; Keltner, Dacher

    2009-12-15

    Oxytocin, a peptide that functions as both a hormone and neurotransmitter, has broad influences on social and emotional processing throughout the body and the brain. In this study, we tested how a polymorphism (rs53576) of the oxytocin receptor relates to two key social processes related to oxytocin: empathy and stress reactivity. Compared with individuals homozygous for the G allele of rs53576 (GG), individuals with one or two copies of the A allele (AG/AA) exhibited lower behavioral and dispositional empathy, as measured by the "Reading the Mind in the Eyes" Test and an other-oriented empathy scale. Furthermore, AA/AG individuals displayed higher physiological and dispositional stress reactivity than GG individuals, as determined by heart rate response during a startle anticipation task and an affective reactivity scale. Our results provide evidence of how a naturally occurring genetic variation of the oxytocin receptor relates to both empathy and stress profiles.

  3. Does the arrival index predict physiological stress reactivity in children.

    Science.gov (United States)

    de Veld, Danielle M J; Riksen-Walraven, J Marianne; de Weerth, Carolina

    2014-09-01

    Knowledge about children's stress reactivity and its correlates is mostly based on one stress task, making it hard to assess the generalizability of the results. The development of an additional stress paradigm for children, that also limits stress exposure and test time, could greatly advance this field of research. Research in adults may provide a starting point for the development of such an additional stress paradigm, as changes in salivary cortisol and alpha-amylase (sAA) over a 1-h pre-stress period in the laboratory correlated strongly with subsequent reactivity to stress task (Balodis et al., 2010, Psychoneuroendocrinology 35:1363-73). The present study examined whether such strong correlations could be replicated in 9- to 11-year-old children. Cortisol and sAA samples were collected from 158 children (83 girls) during a 2.5-h visit to the laboratory. This visit included a 1-h pre-stress period in which children performed some non-stressful tasks and relaxed before taking part in a psychosocial stress task (TSST-C). A higher cortisol arrival index was significantly and weakly correlated with a higher AUCg but unrelated to cortisol reactivity to the stressor. A higher sAA arrival index was significantly and moderately related to lower stress reactivity and to a lower AUCi. Children's personality and emotion regulation variables were unrelated to the cortisol and sAA arrival indices. The results of this study do not provide a basis for the development of an additional stress paradigm for children. Further replications in children and adults are needed to clarify the potential meaning of an arrival index.

  4. Stress generation and hierarchical fracturing in reactive systems

    Science.gov (United States)

    Jamtveit, B.; Iyer, K.; Royne, A.; Malthe-Sorenssen, A.; Mathiesen, J.; Feder, J.

    2007-12-01

    Hierarchical fracture patterns are the result of a slowly driven fracturing process that successively divides the rocks into smaller domains. In quasi-2D systems, such fracture patterns are characterized by four sided domains, and T-junctions where new fractures stop at right angles to pre-existing fractures. We describe fracturing of mm to dm thick enstatite layers in a dunite matrix from the Leka ophiolite complex in Norway. The fracturing process is driven by expansion of the dunite matrix during serpentinization. The cumulative distributions of fracture lengths show a scaling behavior that lies between a log - normal and power law (fractal) distribution. This is consistent with a simple fragmentation model in which domains are divided according to a 'top hat' distribution of new fracture positions within unfractured domains. Reaction-assisted hierarchical fracturing is also likely to be responsible for other (3-D) structures commonly observed in serpentinized ultramafic rocks, including the mesh-textures observed in individual olivine grains, and the high abundance of rectangular domains at a wide range of scales. Spectacular examples of 3-D hierarchical fracture patterns also form during the weathering of basaltic intrusions (dolerites). Incipient chemical weathering of dolerites in the Karoo Basin in South Africa occurs around water- filled fractures, originally produced by thermal contraction or by externally imposed stresses. This chemical weathering causes local expansion of the rock matrix and generates elastic stresses. On a mm to cm scale, these stresses lead to mechanical layer-by-layer spalling, producing the characteristic spheroidal weathering patterns. However, our field observations and computer simulations demonstrate that in confined environments, the spalling process alone is unable to relieve the elastic stresses. In such cases, chemical weathering drives a much larger scale hierarchical fracturing process in which fresh dolerite undergoes a

  5. Character strengths, social anxiety, and physiological stress reactivity

    Directory of Open Access Journals (Sweden)

    Tingting Li

    2017-05-01

    Full Text Available In this paper, the effects of character strengths on the physiological reactivity to social anxiety induced by the Trier Social Stress Task were reported. On the basis of their scores in the Chinese Virtues Questionnaire, 30 college students were assigned to either high- (n = 15 or low-character-strength (n = 15 groups. Their psychological stress and physiological data across three laboratory stages (namely, baseline, stress exposure, and post-stress were collected. Results indicated that individuals with high character strengths exhibited rapid cardiovascular recovery from baseline to post-stress even if high- and low-character-strength groups showed similar patterns of cardiovascular arousal in response to the stress at baseline and stress exposure. These results prove that character strengths are stress-defense factors that allow for psychological and physiological adaptation to stress.

  6. The Role of Chronic Psychosocial Stress in Explaining Racial Differences in Stress Reactivity and Pain Sensitivity.

    Science.gov (United States)

    Gordon, Jennifer L; Johnson, Jacqueline; Nau, Samantha; Mechlin, Beth; Girdler, Susan S

    To examine the role of psychosocial factors in mediating the relationship between African American (AA) race and both increased pain sensitivity and blunted stress reactivity. Participants included 133 AA and non-Hispanic white (nHW) individuals (mean [SD] age, 37 [9]) matched for age, sex, and socioeconomic status. Participants underwent mental stress testing (Trier Social Stress Test) while cardiovascular, hemodynamic, and neuroendocrine reactivity were measured. Participants completed questionnaires assessing potential sources of psychosocial stress and were tested for pain responses to cold pain and the temporal summation of heat pulses. Mediation analyses were used to determine the extent to which exposure to psychosocial stress accounted for the observed racial differences in stress reactivity and pain. Chronic stress exposure and reactivity to mental stress was largely similar among AAs and nHWs; however, AAs exhibited heightened pain to both cold (p = .012) and heat (p = .004). Racial differences in the relationship between stress reactivity and pain were also observed: while greater stress reactivity was associated with decreased pain among nHWs, reactivity was either unrelated to or even positively associated with pain among AAs (e.g., r = -.21 among nHWs and r = .41 among AAs for stroke volume reactivity and cold pressor intensity). Adjusting for minor racial differences in chronic psychosocial stress did not change these findings. Accounting for psychosocial factors eliminated racial differences in stress reactivity but not racial differences in sensitivity to experimental pain tasks. Increased exposure to chronic stress may not explain AAs' increased pain sensitivity in laboratory settings.

  7. Reactive diffusion and stresses in nanowires or nanorods

    International Nuclear Information System (INIS)

    Roussel, Manuel; Erdélyi, Zoltán; Schmitz, Guido

    2017-01-01

    Heterostructured nanowires are of prime interest in nowadays technology such as field-effect transistors, field emitters, batteries and solar cells. We consider their aging behavior and developed a model focusing on reactive diffusion in core-shell nanowires. A complete set of analytical equations is presented that takes into account thermodynamic driving forces, vacancy distribution, elastic stress and its plastic relaxation. This complete description of the reactive diffusion can be used in finite element simulations to investigate diffusion processes in various geometries. In order to show clearly the interplay between the cylindrical geometry, the reactive diffusion and the stresses developing in the nanowire, we investigate the formation of an intermetallic reaction product in various core-shell geometries. Emphasis is placed on showing how it is possible to control the kinetics of the reaction by applying an axial stress to the nanowires.

  8. Subjective stress reactivity in psoriasis - a cross sectional study of associated psychological traits.

    Science.gov (United States)

    Remröd, Charlotta; Sjöström, Karin; Svensson, Åke

    2015-05-02

    Stress or psychological distress is often described as a causative or maintaining factor in psoriasis. Psychological traits may influence the appraisal, interpretation and coping ability regarding stressful situations. Detailed investigations of psychological traits in relation to stress reactivity in psoriasis are rare. The aim of this study was to examine whether patients with psoriasis who report an association between psychological distress and exacerbation, "stress reactors" (SRs), differ psychologically from those with no stress reactivity "non-stress reactors" (NSRs). This cross-sectional study was conducted among 101 consecutively recruited outpatients with plaque psoriasis. A psychosocial interview was performed including questions concerning stress reactivity in relation to onset and exacerbation. Three validated self-rating scales were used: Spielberger State-Trait Anxiety Inventory (STAI, Form-Y), Beck Depression Inventory (BDI-II) and Swedish Universities Scales of Personality (SSP). Independent samples t-tests, Chi-square tests and one-way ANOVA analyses were used for group comparisons when appropriate. A logistic regression model was designed with SR as the dependent variable. Sixty-four patients (63%) reported a subjective association between disease exacerbation and stress (SRs). Patients defined as SRs reported significantly higher mean scores regarding state and trait anxiety, depression, and also five SSP scale personality traits, i.e. somatic trait anxiety, psychic trait anxiety, stress susceptibility, lack of assertiveness and mistrust, compared with NSRs. In multivariate analysis, SSP-stress susceptibility was the strongest explanatory variable for SR, i.e. OR (95% CI)=1.13 (1.02 - 1.24), p=0.018. According to our results, patients who perceive stress as a causal factor in their psoriasis might have a more vulnerable psychological constitution. This finding suggests important opportunities for clinicians to identify patients who may benefit

  9. Stress and Sleep Reactivity: A Prospective Investigation of the Stress-Diathesis Model of Insomnia

    Science.gov (United States)

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

    2014-01-01

    Study Objectives: To prospectively assess sleep reactivity as a diathesis of insomnia, and to delineate the interaction between this diathesis and naturalistic stress in the development of insomnia among normal sleepers. Design: Longitudinal. Setting: Community-based. Participants: 2,316 adults from the Evolution of Pathways to Insomnia Cohort (EPIC) with no history of insomnia or depression (46.8 ± 13.2 y; 60% female). Interventions: None. Measurements and Results: Participants reported the number of stressful events they encountered at baseline (Time 1), as well as the level of cognitive intrusion they experienced in response to each stressor. Stressful events (OR = 1.13; P insomnia one year hence (Time 2). Intrusion mediated the effects of stressful events on risk for insomnia (P insomnia (OR = 1.78; P insomnia as a function of intrusion was significantly higher in individuals with high sleep reactivity. Trait sleep reactivity also constituted a significant risk for depression (OR = 1.67; P Insomnia at Time 2 significantly mediated this effect (P insomnia, and that it triggers insomnia by exacerbating the effects of stress-induced intrusion. Sleep reactivity is also a precipitant of depression, as mediated by insomnia. These findings support the stress-diathesis model of insomnia, while highlighting sleep reactivity as an important diathesis. Citation: Drake CL, Pillai V, Roth T. Stress and sleep reactivity: a prospective investigation of the stress-diathesis model of insomnia. SLEEP 2014;37(8):1295-1304. PMID:25083009

  10. Sex Differences in Adolescent Depression: Stress Exposure and Reactivity Models

    Science.gov (United States)

    Hankin, Benjamin L.; Mermelstein, Robin; Roesch, Linda

    2007-01-01

    Stress exposure and reactivity models were examined as explanations for why girls exhibit greater levels of depressive symptoms than boys. In a multiwave, longitudinal design, adolescents' depressive symptoms, alcohol usage, and occurrence of stressors were assessed at baseline, 6, and 12 months later (N=538; 54.5% female; ages 13-18, average…

  11. Laboratory and field scale demonstration of reactive barrier systems

    International Nuclear Information System (INIS)

    Dwyer, B.P.; Marozas, D.C.; Cantrell, K.; Stewart, W.

    1996-10-01

    In an effort to devise a cost efficient technology for remediation of uranium contaminated groundwater, the Department of Energy's Uranium Mill Tailings Remedial Action (DOE-UMTRA) Program through Sandia National Laboratories (SNL) fabricated a pilot scale research project utilizing reactive subsurface barriers at an UMTRA site in Durango, Colorado. A reactive subsurface barrier is produced by placing a reactant material (in this experiment, metallic iron) in the flow path of the contaminated groundwater. The reactive media then removes and/or transforms the contaminant(s) to regulatory acceptable levels. Experimental design and results are discussed with regard to other potential applications of reactive barrier remediation strategies at other sites with contaminated groundwater problems

  12. Temporal discounting and heart rate reactivity to stress.

    Science.gov (United States)

    Diller, James W; Patros, Connor H G; Prentice, Paula R

    2011-07-01

    Temporal discounting is the reduction of the value of a reinforcer as a function of increasing delay to its presentation. Impulsive individuals discount delayed consequences more rapidly than self-controlled individuals, and impulsivity has been related to substance abuse, gambling, and other problem behaviors. A growing body of literature has identified biological correlates of impulsivity, though little research to date has examined relations between delay discounting and markers of poor health (e.g., cardiovascular reactivity to stress). We evaluated the relation between one aspect of impulsivity, measured using a computerized temporal discounting task, and heart rate reactivity, measured as a change in heart rate from rest during a serial subtraction task. A linear regression showed that individuals who were more reactive to stress responded more impulsively (i.e., discounted delayed reinforcers more rapidly). When results were stratified by gender, the effect was observed for females, but not for males. This finding supports previous research on gender differences in cardiovascular reactivity and suggests that this type of reactivity may be an important correlate of impulsive behavior. Copyright © 2011 Elsevier B.V. All rights reserved.

  13. Influence of life stress on immunological reactivity to mild psychological stress

    NARCIS (Netherlands)

    Brosschot, J. F.; Benschop, R. J.; Godaert, G. L.; Olff, M.; de Smet, M.; Heijnen, C. J.; Ballieux, R. E.

    1994-01-01

    This study investigated the effects of self-reported life stress and locus of control on reactivity of several immune parameters to a mild and short-lasting interpersonal stressor. Subjects were 86 male teachers aged 24 to 55 years. Immune reactivity was defined as changes in numbers of monocytes.

  14. Occupational status and job stress in relation to cardiovascular stress reactivity in Japanese workers.

    Science.gov (United States)

    Hirokawa, Kumi; Ohira, Tetsuya; Nagayoshi, Mako; Kajiura, Mitsugu; Imano, Hironori; Kitamura, Akihiko; Kiyama, Masahiko; Okada, Takeo; Iso, Hiroyasu

    2016-12-01

    This study aimed to investigate the effects of occupational status and job stress factors on cardiovascular stress reactivity in Japanese workers. In this baseline assessment between 2001 and 2009 in Osaka, Japan, we examined 928 healthy Japanese employees (330 men, 598 women) from two occupational statuses: managers/professionals and general workers. A brief job stress questionnaire was used to evaluate job stress levels. Systolic and diastolic blood pressure (SBP, DBP), heart rate, heart rate variability (high-frequency [HF], low-frequency [LF], LF/HF], and peripheral blood flow were measured at rest and during two stressful tasks. Changes in stress reactivity were calculated as the difference between the measured variables during the tasks and the rest period. Men showed inverse associations between quantitative job overload and DBP, heart rate, and LF/HF, between physical demands and blood pressure (SBP, DBP), and between a poor physical environment and HF. Men also had positive associations between qualitative job overload and heart rate, and between physical demands and peripheral blood flow (all p occupational status, significant associations between job stress and changes in stress reactivity were observed in male managers/professionals and female general workers (p stress levels are associated with changes in cardiovascular stress reactivity in men and women. Occupational status may modify these associations.

  15. Occupational role stress is associated with higher cortisol reactivity to acute stress.

    Science.gov (United States)

    Wirtz, Petra H; Ehlert, Ulrike; Kottwitz, Maria U; La Marca, Roberto; Semmer, Norbert K

    2013-04-01

    We investigated whether occupational role stress is associated with differential levels of the stress hormone cortisol in response to acute psychosocial stress. Forty-three medication-free nonsmoking men aged between 22 and 65 years (mean ± SEM: 44.5 ± 2) underwent an acute standardized psychosocial stress task combining public speaking and mental arithmetic in front of an audience. We assessed occupational role stress in terms of role conflict and role ambiguity (combined into a measure of role uncertainty) as well as further work characteristics and psychological control variables including time pressure, overcommitment, perfectionism, and stress appraisal. Moreover, we repeatedly measured salivary cortisol and blood pressure levels before and after stress exposure, and several times up to 60 min thereafter. Higher role uncertainty was associated with a more pronounced cortisol stress reactivity (p = .016), even when controlling for the full set of potential confounders (p stress reactivity was not associated with role uncertainty. Our findings suggest that occupational role stress in terms of role uncertainty acts as a background stressor that is associated with increased HPA-axis reactivity to acute stress. This finding may represent a potential mechanism regarding how occupational role stress may precipitate adverse health outcomes.

  16. Work-related social support modulates effects of early life stress on limbic reactivity during stress.

    Science.gov (United States)

    Leicht-Deobald, Ulrich; Bruch, Heike; Bönke, Luisa; Stevense, Amie; Fan, Yan; Bajbouj, Malek; Grimm, Simone

    2017-12-15

    Early life stress (ELS) affects stress- reactivity via limbic brain regions implicated such as hippocampus and amygdala. Social support is a major protective factor against ELS effects, while subjects with ELS experience reportedly perceive less of it in their daily life. The workplace, where most adults spend a substantial amount of time in their daily lives, might serve as a major resource for social support. Since previous data demonstrated that social support attenuates stress reactivity, we here used a psychosocial stress task to test the hypothesis that work-related social support modulates the effects of ELS. Results show decreased amygdala reactivity during stress in ELS subjects who report high levels of work- related social support, thereby indicating a signature for reduced stress reactivity. However, this effect was only observable on the neural, but not on the behavioral level, since social support had no buffering effect regarding the subjective experience of stress in daily life as well as regarding feelings of uncontrollability induced by the stress task. Accordingly, our data suggest that subjects with ELS experiences might benefit from interventions targeted at lowering their subjective stress levels by helping them to better perceive the availability of social support in their daily lives.

  17. Free radicals, reactive oxygen species, oxidative stress and its classification.

    Science.gov (United States)

    Lushchak, Volodymyr I

    2014-12-05

    Reactive oxygen species (ROS) initially considered as only damaging agents in living organisms further were found to play positive roles also. This paper describes ROS homeostasis, principles of their investigation and technical approaches to investigate ROS-related processes. Especial attention is paid to complications related to experimental documentation of these processes, their diversity, spatiotemporal distribution, relationships with physiological state of the organisms. Imbalance between ROS generation and elimination in favor of the first with certain consequences for cell physiology has been called "oxidative stress". Although almost 30years passed since the first definition of oxidative stress was introduced by Helmut Sies, to date we have no accepted classification of oxidative stress. In order to fill up this gape here classification of oxidative stress based on its intensity is proposed. Due to that oxidative stress may be classified as basal oxidative stress (BOS), low intensity oxidative stress (LOS), intermediate intensity oxidative stress (IOS), and high intensity oxidative stress (HOS). Another classification of potential interest may differentiate three categories such as mild oxidative stress (MOS), temperate oxidative stress (TOS), and finally severe (strong) oxidative stress (SOS). Perspective directions of investigations in the field include development of sophisticated classification of oxidative stresses, accurate identification of cellular ROS targets and their arranged responses to ROS influence, real in situ functions and operation of so-called "antioxidants", intracellular spatiotemporal distribution and effects of ROS, deciphering of molecular mechanisms responsible for cellular response to ROS attacks, and ROS involvement in realization of normal cellular functions in cellular homeostasis. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  18. Dual-hormone stress reactivity predicts downstream war-zone stress-evoked PTSD.

    Science.gov (United States)

    Josephs, Robert A; Cobb, Adam R; Lancaster, Cynthia L; Lee, Han-Joo; Telch, Michael J

    2017-04-01

    The crucial role of the hypothalamic-pituitary-adrenal axis (HPA) in stress-related homeostasis suggests dysregulated HPA involvement in the pathogenesis of post-traumatic stress disorder (PTSD), yet most studies examining linkages between HPA axis measures and PTSD have yielded null findings. One untested explanation for this inconsistency is a failure to account for simultaneous adrenal and gonadal influence. Here we tested the singular and interactive effects of cortisol (C R ) and testosterone (T R ) reactivity as moderators of war-zone stress evoked PTSD emergence in the war-zone. U.S. soldiers (N=120) scheduled for deployment to Iraq completed pre-deployment measures of C R and T R stress reactivity to a CO 2 inhalation challenge. Once deployed, monthly assessments of exposure to traumatic war-zone stressors and PTSD symptoms were collected via a web-based assessment system. Cortisol hypo-reactivity potentiated the pathogenic impact of war-zone stressors only in soldiers for whom the CO 2 challenge did not elevate testosterone, suggesting that the dual hormone stress reactivity profile of blunted cortisol and testosterone may confer increased risk for PTSD emergence by potentiating the pathogenic effects of war-zone stressors. Findings underscore the utility of assessing both HPA and HPG stress reactivity when assessing PTSD vulnerability and may help inform efforts for enhanced soldier screening and inoculation to war-zone stressors. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Autonomic stress reactivity and craving in individuals with problematic Internet use.

    Science.gov (United States)

    Moretta, Tania; Buodo, Giulia

    2018-01-01

    The link between autonomic stress reactivity and subjective urge/craving has been less systematically examined in behavioral addictions (i.e. problematic Internet use) than in substance use disorders. The present study investigated whether problematic Internet users (PU) show enhanced autonomic stress reactivity than non-PU, indexed by lower Heart Rate Variability (HRV) and higher Skin Conductance Level (SCL) reactivity during the Trier Social Stress Test (TSST), whether greater reactivity is related to stronger Internet craving, and whether problematic Internet usage is associated with some dysfunctional psychological features. Based on their Internet Addiction Test scores, participants were divided into PU (N = 24) and non-PU (N = 21). Their heart rate and skin conductance were continuously recorded during baseline, social stressors, and recovery. Craving for Internet usage were collected using a Likert scale before and after the TSST. The SDNN, an overall measure of HRV, was significantly lower in PU than non-PU during baseline, but not during and after stressful task. Furthermore, only among PU a significant negative correlation emerged between SDNN during recovery and craving ratings after the test. No group differences emerged for SCL. Lastly, PU endorsed more mood, obsessive-compulsive, and alcohol-related problems. Our findings suggest that problems in controlling one's use of the Internet may be related to reduced autonomic balance at rest. Moreover, our results provide new insights into the characterization of craving in PIU, indicating the existence of a relationship between craving for Internet usage and reduced autonomic flexibility.

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

    Science.gov (United States)

    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.

  1. Cardiovascular reactivity to acute psychological stress following sleep deprivation.

    Science.gov (United States)

    Franzen, Peter L; Gianaros, Peter J; Marsland, Anna L; Hall, Martica H; Siegle, Greg J; Dahl, Ronald E; Buysse, Daniel J

    2011-10-01

    Psychological stress and sleep disturbances are highly prevalent and are both implicated in the etiology of cardiovascular diseases. Given the common co-occurrence of psychological distress and sleep disturbances including short sleep duration, this study examined the combined effects of these two factors on blood pressure reactivity to immediate mental challenge tasks after well-rested and sleep-deprived experimental conditions. Participants (n = 20) were healthy young adults free from current or past sleep, psychiatric, or major medical disorders. Using a within-subjects crossover design, we examined acute stress reactivity under two experimental conditions: after a night of normal sleep in the laboratory and after a night of total sleep deprivation. Two standardized psychological stress tasks were administered, a Stroop color-word naming interference task and a speech task, which were preceded by a prestress baseline period and followed by a poststress recovery period. Each period was 10 minutes in duration, and blood pressure recordings were collected every 2.5 minutes throughout each period. Mean blood pressure responses during stress and recovery periods were examined with a mixed-effects analysis of covariance, controlling for baseline blood pressure. There was a significant interaction between sleep deprivation and stress on systolic blood pressure (F(2,82.7) = 4.05, p = .02). Systolic blood pressure was higher in the sleep deprivation condition compared with the normal sleep condition during the speech task and during the two baseline periods. Sleep deprivation amplified systolic blood pressure increases to psychological stress. Sleep loss may increase cardiovascular risk by dysregulating stress physiology.

  2. Life Satisfaction and Hemodynamic Reactivity to Mental Stress.

    Science.gov (United States)

    Schwerdtfeger, Andreas; Gaisbachgrabner, Kerstin; Traunmüller, Claudia

    2017-06-01

    Satisfaction with life has been considered a health-protective variable, which could impact cardiovascular morbidity and mortality. However, few studies have examined the physiological pathways involved in the potentially salutary effect of life satisfaction. It was hypothesized that life satisfaction should be associated with a cardiovascular response profile that signals challenge (i.e., higher cardiac output, lower peripheral resistance), rather than threat during a mental stress task. A sample of 75 healthy, medication-free men without clinical signs of psychological disorders who worked full-time and occupied highly demanding positions participated in this study. They performed two mental stress tasks (n-back) with varying degrees of difficulty. The tasks were embedded between a baseline and a recovery period. Cardiovascular and hemodynamic variables (heart rate, blood pressure, cardiac output, total peripheral resistance) were recorded by means of impedance cardiography. Individuals who were more satisfied with their life displayed higher cardiac output and lower peripheral resistance levels during the stress tasks, indicating a challenge rather than a threat profile. Findings were robust when controlled for physical activity, smoking, age, and depressive symptoms. Life satisfaction could be positively correlated with beneficial hemodynamic stress reactivity, indicating that individuals with higher levels of life satisfaction can more adaptively cope with stress. Increased cardiac output and decreased peripheral resistance during stress may constitute one route through which life satisfaction can benefit health.

  3. Occupational status and job stress in relation to cardiovascular stress reactivity in Japanese workers

    Directory of Open Access Journals (Sweden)

    Kumi Hirokawa

    2016-12-01

    Full Text Available This study aimed to investigate the effects of occupational status and job stress factors on cardiovascular stress reactivity in Japanese workers. In this baseline assessment between 2001 and 2009 in Osaka, Japan, we examined 928 healthy Japanese employees (330 men, 598 women from two occupational statuses: managers/professionals and general workers. A brief job stress questionnaire was used to evaluate job stress levels. Systolic and diastolic blood pressure (SBP, DBP, heart rate, heart rate variability (high-frequency [HF], low-frequency [LF], LF/HF], and peripheral blood flow were measured at rest and during two stressful tasks. Changes in stress reactivity were calculated as the difference between the measured variables during the tasks and the rest period. Men showed inverse associations between quantitative job overload and DBP, heart rate, and LF/HF, between physical demands and blood pressure (SBP, DBP, and between a poor physical environment and HF. Men also had positive associations between qualitative job overload and heart rate, and between physical demands and peripheral blood flow (all p < 0.05. Women showed inverse associations between qualitative job overload and SBP, and showed positive associations between qualitative job overload and peripheral blood flow, and between a poor physical environment and SBP (all p < 0.05. When stratified by occupational status, significant associations between job stress and changes in stress reactivity were observed in male managers/professionals and female general workers (p < 0.05. Job stress levels are associated with changes in cardiovascular stress reactivity in men and women. Occupational status may modify these associations.

  4. Social support and loneliness in college students: effects on pulse pressure reactivity to acute stress.

    Science.gov (United States)

    O'Donovan, Aoife; Hughes, Brian

    2007-01-01

    Socially supportive relationships at university may buffer against psychological stress in students, particularly in those experiencing loneliness. To examine the relation of social support at university and loneliness with pulse pressure (PP) reactivity to acute psychological stress in a sample of first-year undergraduate students. Sixty-five female, adolescent, first-year university students. Pulse pressure (PP) was calculated as the arithmetic difference between systolic blood pressure and diastolic blood pressure, which were measured during a resting baseline and during a stressful reading task. The difference between baseline and reading task PP represents PP reactivity. The Social Support at University Scale (SSUS) was used to assess social support availability in university, and the Revised UCLA Loneliness Scale was used to assess loneliness. Hierarchical linear regression was used to examine main and interactive effects of SSUS and loneliness on PP change scores, and simple slopes were computed to assist in the interpretation of interaction effects. Social support at university was associated with lower PP reactivity in students reporting medium (t = -2.03, p = .04) or high levels of loneliness (t = -2.93, p = .004), but not in those reporting low levels of loneliness (t = -0.20, p = .83). Psychosocial interventions designed to increase social support available at university, and targeted at students experiencing loneliness may buffer against the harmful effects of acute stressors in lonely first-year students.

  5. Coping with racism: the impact of prayer on cardiovascular reactivity and post-stress recovery in African American women.

    Science.gov (United States)

    Cooper, Denise C; Thayer, Julian F; Waldstein, Shari R

    2014-04-01

    Prayer is often used to cope with racism-related stress. Little is known about its impact on cardiovascular function. This study examined how prayer coping relates to cardiovascular reactivity (CVR), post-stress recovery, and affective reactivity in response to racism-related stress. African American women (n =81; mean age=20 years) reported their use of prayer coping on the Perceived Racism Scale and completed anger recall and racism recall tasks while undergoing monitoring of systolic and diastolic blood pressure (DBP), heart rate, heart rate variability (HRV), and hemodynamic measures. Prayer coping was examined for associations with CVR, recovery, and affective change scores using general linear models with repeated measures. Higher prayer coping was associated with decreased state stress and DBP reactivity during racism recall (p'sracism recall recovery(p'sracism by utilizing prayer may have cardiovascular benefits for African American women.

  6. Psychometric Validation of Stress and Compliance Scale for ...

    African Journals Online (AJOL)

    Keywords: Diabetes mellitus, Malaysia stress scale, Stress and compliance scale for diabetes, Stress, ... and 'Rate your life on current life satisfaction scale!' People rated how often they ..... Handbook of depression in children and adolescents.

  7. Boosting recovery rather than buffering reactivity: Higher stress-induced oxytocin secretion is associated with increased cortisol reactivity and faster vagal recovery after acute psychosocial stress.

    Science.gov (United States)

    Engert, Veronika; Koester, Anna M; Riepenhausen, Antje; Singer, Tania

    2016-12-01

    Animal models and human studies using paradigms designed to stimulate endogenous oxytocin release suggest a stress-buffering role of oxytocin. We here examined the involvement of stress-induced peripheral oxytocin secretion in reactivity and recovery phases of the human psychosocial stress response. Healthy male and female participants (N=114) were subjected to a standardized laboratory stressor, the Trier Social Stress Test. In addition to plasma oxytocin, cortisol was assessed as a marker of hypothalamic-pituitary-adrenal (HPA-) axis activity, alpha-amylase and heart rate as markers of sympathetic activity, high frequency heart rate variability as a marker of vagal tone and self-rated anxiety as an indicator of subjective stress experience. On average, oxytocin levels increased by 51% following psychosocial stress. The stress-induced oxytocin secretion, however, did not reduce stress reactivity. To the contrary, higher oxytocin secretion was associated with greater cortisol reactivity and peak cortisol levels in both sexes. In the second phase of the stress response the opposite pattern was observed, with higher oxytocin secretion associated with faster vagal recovery. We suggest that after an early stage of oxytocin and HPA-axis co-activation, the stress-reducing action of oxytocin unfolds. Due to the time lag it manifests as a recovery-boosting rather than a reactivity-buffering effect. By reinforcing parasympathetic autonomic activity, specifically during stress recovery, oxytocin may provide an important protective function against the health-compromising effects of sustained stress. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Industrial scale salt-free reactive dyeing of cationized cotton fabric with different reactive dye chemistry.

    Science.gov (United States)

    Nallathambi, Arivithamani; Venkateshwarapuram Rengaswami, Giri Dev

    2017-10-15

    Dyeing of knitted cotton goods in the industry has been mostly with reactive dyes. Handling of salt laden coloured effluent arising out of dyeing process is one of the prime concerns of the industry. Cationization of cotton is one of the effective alternative to overcome the above problem. But for cationization to be successful at industrial scale it has to be carried out by exhaust process and should be adoptable for the various dye chemistries currently practiced in the industry. Hence, in the present work, industrial level exhaust method of cationization process was carried out with concentration of 40g/L and 80g/L. The fabrics were dyed with dyes of three different dye chemistry and assessed for its dyeing performance without the addition of salt. Dye shades ranging from medium to extra dark shades were produced without the addition of salt. This study will provide industries the recipe that can be adopted for cationized cotton fabric for the widely used reactive dyes at industrial level. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Attenuation of Chemical Reactivity of Shale Matrixes following Scale Precipitation

    Science.gov (United States)

    Li, Q.; Jew, A. D.; Kohli, A. H.; Alalli, G.; Kiss, A. M.; Kovscek, A. R.; Zoback, M. D.; Brown, G. E.; Maher, K.; Bargar, J.

    2017-12-01

    Introduction of fracture fluids into shales initiates a myriad of fluid-rock reactions that can strongly influence migration of fluid and hydrocarbon through shale/fracture interfaces. Due to the extremely low permeability of shale matrixes, studies on chemical reactivity of shales have mostly focused on shale surfaces. Shale-fluid interactions inside within shale matrixes have not been examined, yet the matrix is the primary conduit through which hydrocarbons and potential contaminants are transmitted. To characterize changes in matrix mineralogy, porosity, diffusivity, and permeability during hydraulic stimulation, we reacted Marcellus (high clay and low carbonate) and Eagle Ford (low clay and high carbonate) shale cores with fracture fluids for 3 weeks at elevated pressure and temperature (80 oC, and 77 bars). In the carbonate-poor Marcellus system, fluid pH increased from 2 to 4, and secondary Fe(OH)3 precipitates were observed in the fluid. Sulfur X-ray fluorescence maps show that fluids had saturated and reacted with the entire 1-cm-diameter core. In the carbonate-rich Eagle Ford system, pH increased from 2 to 6 due to calcite dissolution. When additional Ba2+ and SO42- were present (log10(Q/K)=1.3), extensive barite precipitation was observed in the matrix of the Eagle Ford core (and on the surface). Barite precipitation was also observed on the surface of the Marcellus core, although to a lesser extent. In the Marcellus system, the presence of barite scale attenuated diffusivity in the matrix, as demonstrated by sharply reduced Fe leaching and much less sulfide oxidation. Systematic studies in homogeneous solution show that barite scale precipitation rates are highly sensitive to pH, salinity, and the presence of organic compounds. These findings imply that chemical reactions are not confined to shale/fluid interfaces but can penetrate into shale matrices, and that barite scale formation can clog diffusion pathways for both fluid and hydrocarbon.

  10. Association between stress-related sleep reactivity and cognitive processes in insomnia disorder and insomnia subgroups: preliminary results.

    Science.gov (United States)

    Palagini, Laura; Faraguna, Ugo; Mauri, Mauro; Gronchi, Alessia; Morin, Charles M; Riemann, Dieter

    2016-03-01

    Stress-related sleep reactivity, sleep-related cognitions, and psychological factors play an important role in insomnia. The aim was to investigate their possible association in Insomnia Disorder, insomnia subgroups, and healthy subjects. The cross-sectional study consisted of 93 subjects who met diagnostic criteria for Insomnia Disorder according to Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) and of 30 healthy subjects. Survey instruments included the Insomnia Severity Index (ISI), Pittsburgh Sleep Quality Index (PSQI), Ford Insomnia Response to Stress Test (FIRST), Dysfunctional Beliefs about Sleep scale (DBAS), Beck Depression Inventory (BDI), and Zung Self-Rating Anxiety Scale (SAS). Descriptive statistics, Pearson correlations, χ(2)-test, and multiple linear regression were performed. FIRST and SAS best determined the insomnia subjects vs good sleepers (FIRST χ(2) = 109.6, p insomnia, stress-related sleep reactivity, and psychological factors, such as anxiety symptoms, may distinguish insomnia subjects from good sleepers; (2) sleep reactivity and sleep-related cognitions seem interrelated, unhelpful beliefs may affect the stress reactivity; (3) psychological factors may influence sleep quality and the severity of insomnia; (4) these important sleep-related variables may have similar associations in insomnia subgroups; they may constitute the core factors for insomnia development and maintenance. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Stress Reactivity to an Electronic Version of the Trier Social Stress Test: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Sage E Hawn

    2015-05-01

    Full Text Available Social stressors that rely on the inclusion of confederates (i.e., Trier Social Stress Test; TSST are often used in clinical laboratory research paradigms to elicit a measurable stress response in participants. Although effective, the TSST is labor intensive and may introduce error variance as a function of confederate race, gender, and/or response characteristics. The present study aimed to develop and validate an electronic version of the TSST (e-TSST. The primary aim was to compare the e-TSST to an e-neutral control condition; the exploratory aim was to compare the magnitude of stress response elicited by the e-TSST to that elicited by the traditional TSST. Forty-three healthy adults were randomized to the e-TSST or e-neutral condition. Subjective (participant-rated distress and objective (cortisol, heart rate and blood pressure indices of stress were collected prior to, and multiple times following, the stressor. Using archival data collected from 19 healthy participants exposed to the traditional TSST in a prior study, stress reactivity was compared between the electronic and traditional versions of the TSST. The e-TSST elicited significant increases in all measures of stress reactivity compared to the e-neutral condition, with the exception of heart rate (HR. Results showed that the magnitude of subjective distress, BP, and HR responses elicited by the e-TSST did not differ significantly from that elicited by the traditional TSST. The traditional TSST elicited significantly higher cortisol than the e-TSST. Although these findings provide initial support for the development of electronic versions of the TSST, further refinement of the e-TSST is warranted prior to broad adoption of this technology. A refined, reliable e-TSST could allow for increased utilization of the TSST by enhancing convenience, reducing labor costs, and limiting potential error variance introduced by human confederates.

  12. Speaking under pressure: low linguistic complexity is linked to high physiological and emotional stress reactivity.

    Science.gov (United States)

    Saslow, Laura R; McCoy, Shannon; van der Löwe, Ilmo; Cosley, Brandon; Vartan, Arbi; Oveis, Christopher; Keltner, Dacher; Moskowitz, Judith T; Epel, Elissa S

    2014-03-01

    What can a speech reveal about someone's state? We tested the idea that greater stress reactivity would relate to lower linguistic cognitive complexity while speaking. In Study 1, we tested whether heart rate and emotional stress reactivity to a stressful discussion would relate to lower linguistic complexity. In Studies 2 and 3, we tested whether a greater cortisol response to a standardized stressful task including a speech (Trier Social Stress Test) would be linked to speaking with less linguistic complexity during the task. We found evidence that measures of stress responsivity (emotional and physiological) and chronic stress are tied to variability in the cognitive complexity of speech. Taken together, these results provide evidence that our individual experiences of stress or "stress signatures"-how our body and mind react to stress both in the moment and over the longer term-are linked to how complex our speech under stress. Copyright © 2013 Society for Psychophysiological Research.

  13. Distress tolerance and physiological reactivity to stress predict women's problematic alcohol use.

    Science.gov (United States)

    Holzhauer, Cathryn Glanton; Wemm, Stephanie; Wulfert, Edelgard

    2017-06-01

    Research has shown that measures of reactivity to distress-including distress tolerance and physiological reactivity to stress-are dysregulated in women who misuse alcohol. These variables may interact and create a risk profile for young adult women, reflecting patterns of stress reactivity that confer a risk for alcohol misuse. The current study tested this hypothesis by examining the independent and interactive associations of subjective distress tolerance, behavioral distress tolerance, and physiological stress reactivity with women's alcohol misuse. The study was conducted with a sample of 91 college women recruited on a large northeastern university campus. Results showed that subjective levels of distress tolerance and physiological reactivity to stress (skin conductance reactivity, SCR), but not behavioral distress tolerance, were independently associated with alcohol misuse. In addition, subjective distress tolerance moderated the relationship between SCR and negative alcohol-related consequences. Specifically, women with low physiological reactivity (SCR) to a stressful task and greater urge to quickly rid themselves of distress (low subjective distress tolerance) endorsed a significantly greater number of adverse consequences from their alcohol use. These results extend prior findings by showing that, even among a nonclinical sample of women, lower stress reactivity in combination with low subjective distress tolerance is associated with increased risk for various drinking-related negative consequences. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  14. Laboratory scale micro-seismic monitoring of rock faulting and injection-induced fault reactivation

    Science.gov (United States)

    Sarout, J.; Dautriat, J.; Esteban, L.; Lumley, D. E.; King, A.

    2017-12-01

    The South West Hub CCS project in Western Australia aims to evaluate the feasibility and impact of geosequestration of CO2 in the Lesueur sandstone formation. Part of this evaluation focuses on the feasibility and design of a robust passive seismic monitoring array. Micro-seismicity monitoring can be used to image the injected CO2plume, or any geomechanical fracture/fault activity; and thus serve as an early warning system by measuring low-level (unfelt) seismicity that may precede potentially larger (felt) earthquakes. This paper describes laboratory deformation experiments replicating typical field scenarios of fluid injection in faulted reservoirs. Two pairs of cylindrical core specimens were recovered from the Harvey-1 well at depths of 1924 m and 2508 m. In each specimen a fault is first generated at the in situ stress, pore pressure and temperature by increasing the vertical stress beyond the peak in a triaxial stress vessel at CSIRO's Geomechanics & Geophysics Lab. The faulted specimen is then stabilized by decreasing the vertical stress. The freshly formed fault is subsequently reactivated by brine injection and increase of the pore pressure until slip occurs again. This second slip event is then controlled in displacement and allowed to develop for a few millimeters. The micro-seismic (MS) response of the rock during the initial fracturing and subsequent reactivation is monitored using an array of 16 ultrasonic sensors attached to the specimen's surface. The recorded MS events are relocated in space and time, and correlate well with the 3D X-ray CT images of the specimen obtained post-mortem. The time evolution of the structural changes induced within the triaxial stress vessel is therefore reliably inferred. The recorded MS activity shows that, as expected, the increase of the vertical stress beyond the peak led to an inclined shear fault. The injection of fluid and the resulting increase in pore pressure led first to a reactivation of the pre

  15. Lactation and Reactivity to Physical and Psychological Stress

    National Research Council Canada - National Science Library

    Carter, C

    1998-01-01

    .... Studies of basal cortisol levels, cognitive performance and reactivity to stressors were conducted in human subjects during late pregnancy and immediately postpartum in women that were lactating...

  16. Cortisol response mediates the effect of post-reactivation stress exposure on contextualization of emotional memories

    NARCIS (Netherlands)

    Bos, M.G.N.; Jacobs van Goethem, T.H.; Beckers, T.; Kindt, M.

    2014-01-01

    Retrieval of traumatic experiences is often accompanied by strong feelings of distress. Here, we examined in healthy participants whether post-reactivation stress experience affects the context-dependency of emotional memory. First, participants studied words from two distinctive emotional

  17. Systolic blood pressure reactivity during submaximal exercise and acute psychological stress in youth

    Science.gov (United States)

    Background: Studies in youth show an association between systolic blood-pressure (SBP) reactivity to acute psychological stress and carotid artery intima-media thickness (CIMT). However, it has not yet been determined whether SBP reactivity during submaximal exercise is also associated with CIMT i...

  18. Child temperament and parental depression predict cortisol reactivity to stress in middle childhood.

    Science.gov (United States)

    Mackrell, Sarah V M; Sheikh, Haroon I; Kotelnikova, Yuliya; Kryski, Katie R; Jordan, Patricia L; Singh, Shiva M; Hayden, Elizabeth P

    2014-02-01

    Children's cortisol reactivity to stress is an important mediator of depression risk, making the search for predictors of such reactivity an important goal for psychopathologists. Multiple studies have linked maternal depression and childhood behavioral inhibition (BI) independently to child cortisol reactivity, yet few have tested multivariate models of these risks. Further, paternal depression and other child temperament traits, such as positive emotionality (PE), have been largely ignored despite their potential relevance. We therefore examined longitudinal associations between child fear/BI and PE and parental depression, and children's cortisol stress reactivity, in 205 7-year-olds. Paternal depression and child fear/BI predicted greater cortisol stress reactivity at a follow-up of 164 9-year-olds, and maternal depression and child PE interacted to predict children's cortisol reactivity, such that higher child PE predicted lower cortisol reactivity in the context of maternal depression. Results highlight the importance of both parents' depression, as well as multiple facets of child temperament, in developing more comprehensive models of childhood cortisol reactivity to stress. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  19. Group versus individual stress management intervention in breast cancer patients for fatigue and emotional reactivity: a randomised intervention study.

    Science.gov (United States)

    Rissanen, Ritva; Arving, Cecilia; Ahlgren, Johan; Nordin, Karin

    2014-09-01

    Fatigue and emotional reactivity are common among women suffering from breast cancer and might detrimentally affect these women's quality of life. This study evaluates if the stress management delivered either in a group or individual setting would improve fatigue and emotional reactivity among women with a newly diagnosed breast cancer. Participants (n = 304) who reported elevated levels of distress at three-month post-inclusion were randomised between stress management in a group (GSM) (n = 77) or individual (ISM) (n = 78) setting. Participation was declined by 149 women. Participants completed the Multidimensional Fatigue Inventory (MFI-20) and the Everyday Life Stress Scale (ELSS) at the time of inclusion, 3- and 12-month post-inclusion. Analyses were made according to intention to treat and per-protocol principles. Mann-Whitney tests were used to examine differences between the two intervention groups. No significant differences were detected between the GSM and ISM groups on fatigue or emotional reactivity. In addition, there were no changes over time for these outcomes. There were no differences between the two intervention arms with reference to fatigue or emotional reactivity; however, a clinically interesting finding was the low number of women who were interested in participating in a psychosocial intervention. This finding may have clinical implications when psychosocial support is offered to women with a newly diagnosed breast cancer and also in the planning of future studies.

  20. Tuning of redox regulatory mechanisms, reactive oxygen species and redox homeostasis under salinity stress

    Directory of Open Access Journals (Sweden)

    Hossain eSazzad

    2016-05-01

    Full Text Available Soil salinity is a crucial environmental constraint which limits biomass production at many sites on a global scale. Saline growth conditions cause osmotic and ionic imbalances, oxidative stress and perturb metabolism, e.g. the photosynthetic electron flow. The plant ability to tolerate salinity is determined by multiple biochemical and physiological mechanisms protecting cell functions, in particular by regulating proper water relations and maintaining ion homeostasis. Redox homeostasis is a fundamental cell property. Its regulation includes control of reactive oxygen species (ROS generation, sensing deviation from and readjustment of the cellular redox state. All these redox related functions have been recognized as decisive factors in salinity acclimation and adaptation. This review focuses on the core response of plants to overcome the challenges of salinity stress through regulation of ROS generation and detoxification systems and to maintain redox homeostasis. Emphasis is given to the role of NADH oxidase (RBOH, alternative oxidase (AOX, the plastid terminal oxidase (PTOX and the malate valve with the malate dehydrogenase isoforms under salt stress. Overwhelming evidence assigns an essential auxiliary function of ROS and redox homeostasis to salinity acclimation of plants.

  1. Impact of sleep quality on amygdala reactivity, negative affect, and perceived stress.

    Science.gov (United States)

    Prather, Aric A; Bogdan, Ryan; Hariri, Ahmad R

    2013-05-01

    Research demonstrates a negative impact of sleep disturbance on mood and affect; however, the biological mechanisms mediating these links are poorly understood. Amygdala reactivity to negative stimuli has emerged as one potential pathway. Here, we investigate the influence of self-reported sleep quality on associations between threat-related amygdala reactivity and measures of negative affect and perceived stress. Analyses on data from 299 participants (125 men, 50.5% white, mean [standard deviation] age = 19.6 [1.3] years) who completed the Duke Neurogenetics Study were conducted. Participants completed several self-report measures of negative affect and perceived stress. Threat-related (i.e., angry and fearful facial expressions) amygdala reactivity was assayed using blood oxygen level-dependent functional magnetic resonance imaging. Global sleep quality was assessed using the Pittsburgh Sleep Quality Index. Amygdala reactivity to fearful facial expressions predicted greater depressive symptoms and higher perceived stress in poor (β values = 0.18-1.86, p values .05). In sex-specific analyses, men reporting poorer global sleep quality showed a significant association between amygdala reactivity and levels of depression and perceived stress (β values = 0.29-0.44, p values sleep quality or in women, irrespective of sleep quality. This study provides novel evidence that self-reported sleep quality moderates the relationships between amygdala reactivity, negative affect, and perceived stress, particularly among men.

  2. Lactation and Reactivity to Physical and Psychological Stress

    National Research Council Canada - National Science Library

    Carter, C

    1997-01-01

    .... Findings to date include lack of changes in attention and memory functions during pregnancy and lactation, lack of difference in hormonal and anxiety responses to psychological stress, enhanced...

  3. Stress reactivity and personality in extreme sport athletes: The psychobiology of BASE jumpers.

    Science.gov (United States)

    Monasterio, Erik; Mei-Dan, Omer; Hackney, Anthony C; Lane, Amy R; Zwir, Igor; Rozsa, Sandor; Cloninger, C Robert

    2016-12-01

    This is the first report of the psychobiology of stress in BASE jumpers, one of the most dangerous forms of extreme sport. We tested the hypotheses that indicators of emotional style (temperament) predict salivary cortisol reactivity, whereas indicators of intentional goal-setting (persistence and character) predict salivary alpha-amylase reactivity during BASE jumping. Ninety-eight subjects completed the Temperament and Character Inventory (TCI) the day before the jump, and 77 also gave salivary samples at baseline, pre-jump on the bridge over the New River Gorge, and post-jump upon landing. Overall BASE jumpers are highly resilient individuals who are highly self-directed, persistent, and risk-taking, but they are heterogeneous in their motives and stress reactivity in the Hypothalamic-Pituitary-Adrenal (HPA) stress system (cortisol reactivity) and the sympathetic arousal system (alpha-amylase reactivity). Three classes of jumpers were identified using latent class analysis based on their personality profiles, prior jumping experience, and levels of cortisol and alpha-amylase at all three time points. "Masterful" jumpers (class 1) had a strong sense of self-directedness and mastery, extensive prior experience, and had little alpha-amylase reactivity and average cortisol reactivity. "Trustful" jumpers (class 2) were highly cooperative and trustful individuals who had little cortisol reactivity coincident with the social support they experienced prior to jumping. "Courageous" jumpers (class 3) were determined despite anxiety and inexperience, and they had high sympathetic reactivity but average cortisol activation. We conclude that trusting social attachment (Reward Dependence) and not jumping experience predicted low cortisol reactivity, whereas persistence (determination) and not jumping experience predicted high alpha-amylase reactivity. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  4. Differential Exposure and Reactivity to Interpersonal Stress Predict Sex Differences in Adolescent Depression

    Science.gov (United States)

    Shih, Josephine H.; Eberhart, Nicole K.; Hammen, Constance L.; Brennan, Patricia A.

    2006-01-01

    This study tested the hypothesis that higher rates of depression in adolescent girls are explained by their greater exposure and reactivity to stress in the interpersonal domain in a large sample of 15-year-olds. Findings indicate that adolescent girls experienced higher levels of total and interpersonal episodic stress, whereas boys experienced…

  5. Reactivity to Stress and the Cognitive Components of Math Disability in Grade 1 Children

    Science.gov (United States)

    MacKinnon McQuarrie, Maureen A.; Siegel, Linda S.; Perry, Nancy E.; Weinberg, Joanne

    2014-01-01

    This study investigated the relationship among working memory, processing speed, math performance, and reactivity to stress in 83 Grade 1 children. Specifically, 39 children with math disability (MD) were compared to 44 children who are typically achieving (TA) in mathematics. It is the first study to use a physiological index of stress (salivary…

  6. Stress reactivity in childhood functional abdominal pain or irritable bowel syndrome.

    Science.gov (United States)

    Gulewitsch, M D; Weimer, K; Enck, P; Schwille-Kiuntke, J; Hautzinger, M; Schlarb, A A

    2017-01-01

    Frequent abdominal pain (AP) in childhood has been shown to be associated with elevated experience of stress and with deficits in stress coping, but psychophysiological stress reactivity has been studied rarely. We examined whether children with frequent AP show altered reactions of the parasympathetic nervous system and the hypothalamic-pituitary-adrenal (HPA) axis during and following an afternoon laboratory social stress task in comparison to healthy children and children with anxiety disorders. Twenty-four children with frequent AP (18 with functional AP and six with irritable bowel syndrome; M = 9.9 years), and 24 healthy controls underwent stressful free speech and arithmetic tasks. Twelve children with anxiety disorders served as second comparison sample. Groups were compared regarding parasympathetic reaction and saliva cortisol concentration. We found no differences in parasympathetic withdrawal between the groups. Concerning the HPA axis, we detected an attenuated cortisol reactivity in children with AP compared to both other groups. This study provides preliminary evidence that childhood AP is not associated with altered parasympathetic withdrawal during stress. It seems to be related to a down-regulated reactivity of the HPA axis. This pattern was ascertained in comparison to healthy children and also in comparison to children with anxiety disorders. Childhood abdominal pain could be related to down-regulated HPA axis reactivity to stress but not to altered parasympathetic reaction. Children with abdominal pain and children with anxiety disorders exhibit a divergent stress-related HPA axis reaction. © 2016 European Pain Federation - EFIC®.

  7. Exposure to Discrimination and Heart Rate Variability Reactivity to Acute Stress among Women with Diabetes.

    Science.gov (United States)

    Wagner, Julie; Lampert, Rachel; Tennen, Howard; Feinn, Richard

    2015-08-01

    Exposure to racial discrimination has been linked to physiological reactivity. This study investigated self-reported exposure to racial discrimination and parasympathetic [high-frequency heart rate variability (HF-HRV)] and sympathetic (norepinephrine and cortisol) activity at baseline and then again after acute laboratory stress. Lifetime exposure to racial discrimination was measured with the Schedule of Racist Events scale. Thirty-two women (16 Black and 16 White) with type 2 diabetes performed a public speaking stressor. Beat-to-beat intervals were recorded on electrocardiograph recorders, and HF-HRV was calculated using spectral analysis and natural log transformed. Norepinephrine and cortisol were measured in blood. Higher discrimination predicted lower stressor HF-HRV, even after controlling for baseline HF-HRV. When race, age, A1c and baseline systolic blood pressure were also controlled, racial discrimination remained a significant independent predictor of stressor HF-HRV. There was no association between lifetime discrimination and sympathetic markers. In conclusion, preliminary data suggest that among women with type 2 diabetes mellitus (T2DM), exposure to racial discrimination is adversely associated with parasympathetic, but not sympathetic, reactivity. Copyright © 2013 John Wiley & Sons, Ltd.

  8. Reactivity to social stress in ethnic minority men

    NARCIS (Netherlands)

    Gevonden, Martin; Myin-Germeys, Inez; Wichers, Marieke; Booij, Jan; van den Brink, Wim; van Winkel, Ruud; Selten, Jean-Paul

    2016-01-01

    Repeated exposures to social exclusion, through a process of sensitization, may result in larger responses to experiences of social stress. The current study tested the hypothesis that healthy Moroccan-Dutch men respond stronger to social stress than Dutch controls 1) in daily life, and 2) in an

  9. Differentiating anticipatory from reactive cortisol responses to psychosocial stress

    NARCIS (Netherlands)

    Engert, V.; Efanov, S.I.; Duchesne, A.; Vogel, S.; Corbo, V.; Pruessner, J.C.

    2013-01-01

    Most psychosocial stress studies assess the overall cortisol response without further identifying the temporal dynamics within hormone levels. It has been shown, however, that the amplitude of anticipatory cortisol stress levels has a unique predictive value for psychological health. So far, no

  10. Hypothalamic-Pituitary-Adrenal Reactivity to Acute Stress: an Investigation into the Roles of Perceived Stress and Family Resources.

    Science.gov (United States)

    Obasi, Ezemenari M; Shirtcliff, Elizabeth A; Cavanagh, Lucia; Ratliff, Kristen L; Pittman, Delishia M; Brooks, Jessica J

    2017-11-01

    Rurally situated African Americans suffer from chronic exposure to stress that may have a deleterious effect on health outcomes. Unfortunately, research on potential mechanisms that underlie health disparities affecting the African American community has received limited focus in the scientific literature. This study investigated the relationship between perceived stress, family resources, and cortisol reactivity to acute stress. A rural sample of African American emerging adults (N = 60) completed a battery of assessments, the Trier Social Stress Test (TSST), and provided four samples of salivary cortisol: prior to receiving TSST instructions, prior to conducting the speech task, immediately following the TSST, and 15-20 min following the TSST. As predicted, cortisol levels increased in response to a controlled laboratory inducement of acute stress. Moreover, diminished levels of family resources were associated with blunted cortisol reactivity to acute stress. Of note, higher levels of perceived stress over the past month and being male were independently associated with lower levels of cortisol at baseline. Lack of family resources had a blunting relationship on the hypothalamic-pituitary-adrenal axis reactivity. These findings provide biomarker support for the relationship between family resources-an indicator associated with social determinants of health-and stress physiology within a controlled laboratory experiment. Identifying mechanisms that work toward explanation of within-group differences in African American health disparities is both needed and informative for culturally informed prevention and intervention efforts.

  11. Calculation of the void reactivity of CANDU lattices using the SCALE code system

    Energy Technology Data Exchange (ETDEWEB)

    Valko, J. [Technische Univ. Delft (Netherlands). Interfacultair Reactor Inst.; Feher, S. [Technische Univ. Delft (Netherlands). Interfacultair Reactor Inst.; Hoogenboom, J.E. [Technische Univ. Delft (Netherlands). Interfacultair Reactor Inst.; Slobben, J. [Netherlands Energy Research Foundation (ECN), Petten (Netherlands)

    1995-11-01

    The reactivity effect of coolant voiding in CANDU-type fuel lattices has been calculated with different methods using the SCALE code system. The known positive void reactivity coefficient of the original lattice was correctly obtained. A modified fuel bundle containing dysprosium and slightly enriched uranium to eliminate the positive reactivity effect was also calculated. Owing to the increased heterogeneity of this modified fuel the one-dimensional cylindrical calculation with XSDRN proved to be inadequate. Code options allowing bundle geometry were successfully used for the calculation of the strongly space dependent flux and spectrum changes which determine the void reactivity. (orig.).

  12. Biological embedding of perinatal social relationships in infant stress reactivity.

    Science.gov (United States)

    Thomas, Jenna C; Letourneau, Nicole; Bryce, Crystal I; Campbell, Tavis S; Giesbrecht, Gerald F

    2017-05-01

    Whereas significant advances have been made in understanding how exposure to early adversity "gets under the skin" of children to result in long term changes in developmental outcomes, the processes by which positive social relationships become biologically embedded remain poorly understood. The aim of this study was to understand the pathways by which maternal and infant social environments become biologically embedded in infant cortisol reactivity. Two hundred seventy-two pregnant women and their infants were prospectively assessed during pregnancy and at 6 months postpartum. In serial mediation analyses, higher perceived social support from partners during pregnancy was associated with lower infant cortisol reactivity or larger decreases in cortisol in response to a stressor at 6 months of age via lower self-reported prenatal maternal depression and higher mother-infant interaction quality. The findings add to our understanding of how perinatal social relationships become biologically embedded in child development. © 2017 Wiley Periodicals, Inc.

  13. Persistent high job demands and reactivity to mental stress predict future ambulatory blood pressure.

    Science.gov (United States)

    Steptoe, A; Cropley, M

    2000-05-01

    To test the hypothesis that work stress (persistent high job demands over 1 year) in combination with high reactivity to mental stress predict ambulatory blood pressure. Assessment of cardiovascular responses to standardized behavioural tasks, job demands, and ambulatory blood pressure over a working day and evening after 12 months. We studied 81 school teachers (26 men, 55 women), 36 of whom experienced persistent high job demands over 1 year, while 45 reported lower job demands. Participants were divided on the basis of high and low job demands, and high and low systolic pressure reactions to an uncontrollable stress task. Blood pressure and concurrent physical activity were monitored using ambulatory apparatus from 0900 to 2230 h on a working day. Cardiovascular stress reactivity was associated with waist/hip ratio. Systolic and diastolic pressure during the working day were greater in high job demand participants who were stress reactive than in other groups, after adjustment for age, baseline blood pressure, body mass index and negative affectivity. The difference was not accounted for by variations in physical activity. Cardiovascular stress reactivity and sustained psychosocial stress may act in concert to increase cardiovascular risk in susceptible individuals.

  14. Loneliness and acute stress reactivity: A systematic review of psychophysiological studies.

    Science.gov (United States)

    Brown, Eoin G; Gallagher, Stephen; Creaven, Ann-Marie

    2018-05-01

    Physiological reactivity to acute stress has been proposed as a potential biological mechanism by which loneliness may lead to negative health outcomes such as cardiovascular disease. This review was conducted to investigate the association between loneliness and physiological responses to acute stress. A series of electronic databases were systematically searched (PsycARTICLES, PsycINFO, Medline, CINAHL Plus, EBSCOhost, PubMed, SCOPUS, Web of Science, Science Direct) for relevant studies, published up to October 2016. Eleven studies were included in the review. Overall, the majority of studies reported positive associations between loneliness and acute stress responses, such that higher levels of loneliness were predictive of exaggerated physiological reactions. However, in a few studies, loneliness was also linked with decreased stress responses for particular physiological outcomes, indicating the possible existence of blunted relationships. There was no clear pattern suggesting any sex- or stressor-based differences in these associations. The available evidence supports a link between loneliness and atypical physiological reactivity to acute stress. A key finding of this review was that greater levels of loneliness are associated with exaggerated blood pressure and inflammatory reactivity to acute stress. However, there was some indication that loneliness may also be related to blunted cardiac, cortisol, and immune responses. Overall, this suggests that stress reactivity could be one of the biological mechanisms through which loneliness impacts upon health. © 2017 Society for Psychophysiological Research.

  15. Lack of Resilience Is Related to Stress-Related Sleep Reactivity, Hyperarousal, and Emotion Dysregulation in Insomnia Disorder.

    Science.gov (United States)

    Palagini, Laura; Moretto, Umberto; Novi, Martina; Masci, Isabella; Caruso, Danila; Drake, Christopher L; Riemann, Dieter

    2018-05-15

    According to the diathesis-stress model of insomnia, insomnia may develop in vulnerable individuals in response to stress. Resilience is a psychobiological factor that determines an individual's capacity to adapt successfully to stressful events and low resilience increases vulnerability for development of mental disorders. The aim was to explore resilience in subjects with insomnia and its relationship with the factors that contribute to its development and perpetuation. The study consisted of 58 subjects with Insomnia Disorder according to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition and 38 good sleepers. Resilience Scale for Adults (RSA), Ford Insomnia Response to Stress Test (FIRST), Pre-sleep Arousal Scale (PSAS), and Difficulties in Emotion Regulation Scale (DERS) were administered while taking into account psychiatric symptoms. Differences in means between groups were assessed using t test or Mann-Whitney U /Wilcoxon test. Linear/multivariable regression analyses and mediation analyses were performed. Subjects with insomnia (24 females, mean age 49 ± 2.1 years) had lower RSA and higher FIRST, DERS, and PSAS scores than good sleepers (22 females, mean age 47.2 ± 1.2 years). After controlling for anxiety/depressive symptoms, low resilience correlated with high stress-related sleep reactivity ( P = .004), pre-sleep cognitive hyperarousal ( P = .01) and emotion dysregulation ( P = .01). Emotion dysregulation mediated the relationship between low resilience and cognitive hyperarousal (Z = 2.06, P = .03). Subjects with insomnia showed low resilience, which was related to high stress-related sleep reactivity, emotional dysregulation, and hyperarousal. If resilience helps to minimize the extent of pathogenesis in the developmental process, an early identification of vulnerable candidates should be useful for preventing insomnia development and maintenance. A commentary on this article appears in this issue on page 709. © 2018 American

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

    Science.gov (United States)

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

    2018-04-01

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

  17. The BDNF Val66Met polymorphism affects HPA-axis reactivity to acute stress.

    Science.gov (United States)

    Alexander, Nina; Osinsky, Roman; Schmitz, Anja; Mueller, Eva; Kuepper, Yvonne; Hennig, Juergen

    2010-07-01

    Growing evidence suggests that individual differences in HPA-axis reactivity to psychosocial stress are partly due to heritable influences. However, knowledge about the role of specific genetic variants remains very limited to date. Since brain-derived neurotrophic factor (BDNF) not only exhibits neurotrophic actions but is also involved in the regulation of hypothalamic neuropeptides, we investigated the role of a common functional polymorphism within the BDNF gene (BDNF Val66Met) in the context of endocrine and cardiovascular stress reactivity. Healthy male adults (N=100) were genotyped and exposed to a standardized laboratory stress task (Public Speaking). Saliva cortisol and self-reported mood levels were obtained at 6 time points prior to the stressor and during an extended recovery period. Furthermore, heart rate reactivity as an indicator of sympathetic activation was monitored continuously during the experimental procedure. We report a small, but significant effect of the BDNF Val66Met polymorphism on stress reactivity. More precisely, carriers of the met-allele showed a significantly attenuated HPA-axis and cardiovascular reactivity to the psychosocial stressor compared to subjects with the val/val genotype. Furthermore, the diminished physiological response in met-allele carriers was also attended by significantly lower self-reported ratings of perceived stress and nervousness. Our findings of a diminished endocrine and cardiovascular stress response in healthy male adults is consistent with a previously published study and adds further evidence for a crucial role of the BDNF Val66Met polymorphism in the modulation of stress reactivity. Copyright 2010. Published by Elsevier Ltd.

  18. Poor habitual sleep efficiency is associated with increased cardiovascular and cortisol stress reactivity in men.

    Science.gov (United States)

    Massar, Stijn A A; Liu, Jean C J; Mohammad, Nabilah B; Chee, Michael W L

    2017-07-01

    Inadequate sleep and psychological stress can both elevate physiological stress markers, such as cortisol. Prior studies that have applied induced psychosocial stress after a night of experimental sleep deprivation have found these effects to be compounded. We examined whether the relationship between stress reactivity and poor sleep also extends to habitual sleep patterns. Fifty-nine adult male participants were recruited. Habitual sleep patterns were monitored with actigraphy for a week. Participants subsequently underwent the Trier Social Stress Test. Cardiovascular responses and salivary cortisol were measured at baseline, during stress, and during recovery. Subjects who showed poor habitual sleep efficiency during the week before stress induction responded with higher stress-related elevations of blood pressure and cortisol levels as compared to subjects with high sleep efficiency. This relationship between poor sleep efficiency and elevated blood pressure persisted during the post-stress recovery period. Similar associations between total sleep time in the week prior to the stress induction and physiological reactivity did not reach significance. Our findings indicate that habitual low sleep efficiency exaggerates cardiovascular and neuroendocrine effects of psychosocial stress, in a male population. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. When bad stress goes good: increased threat reactivity predicts improved category learning performance.

    Science.gov (United States)

    Ell, Shawn W; Cosley, Brandon; McCoy, Shannon K

    2011-02-01

    The way in which we respond to everyday stressors can have a profound impact on cognitive functioning. Maladaptive stress responses in particular are generally associated with impaired cognitive performance. We argue, however, that the cognitive system mediating task performance is also a critical determinant of the stress-cognition relationship. Consistent with this prediction, we observed that stress reactivity consistent with a maladaptive, threat response differentially predicted performance on two categorization tasks. Increased threat reactivity predicted enhanced performance on an information-integration task (i.e., learning is thought to depend upon a procedural-based memory system), and a (nonsignificant) trend for impaired performance on a rule-based task (i.e., learning is thought to depend upon a hypothesis-testing system). These data suggest that it is critical to consider both variability in the stress response and variability in the cognitive system mediating task performance in order to fully understand the stress-cognition relationship.

  20. Increased amygdala reactivity following early life stress: a potential resilience enhancer role.

    Science.gov (United States)

    Yamamoto, Tetsuya; Toki, Shigeru; Siegle, Greg J; Takamura, Masahiro; Takaishi, Yoshiyuki; Yoshimura, Shinpei; Okada, Go; Matsumoto, Tomoya; Nakao, Takashi; Muranaka, Hiroyuki; Kaseda, Yumiko; Murakami, Tsuneji; Okamoto, Yasumasa; Yamawaki, Shigeto

    2017-01-18

    Amygdala hyper-reactivity is sometimes assumed to be a vulnerability factor that predates depression; however, in healthy people, who experience early life stress but do not become depressed, it may represent a resilience mechanism. We aimed to test these hypothesis examining whether increased amygdala activity in association with a history of early life stress (ELS) was negatively or positively associated with depressive symptoms and impact of negative life event stress in never-depressed adults. Twenty-four healthy participants completed an individually tailored negative mood induction task during functional magnetic resonance imaging (fMRI) assessment along with evaluation of ELS. Mood change and amygdala reactivity were increased in never-depressed participants who reported ELS compared to participants who reported no ELS. Yet, increased amygdala reactivity lowered effects of ELS on depressive symptoms and negative life events stress. Amygdala reactivity also had positive functional connectivity with the bilateral DLPFC, motor cortex and striatum in people with ELS during sad memory recall. Increased amygdala activity in those with ELS was associated with decreased symptoms and increased neural features, consistent with emotion regulation, suggesting that preservation of robust amygdala reactions may reflect a stress buffering or resilience enhancing factor against depression and negative stressful events.

  1. Acceptance lowers stress reactivity: Dismantling mindfulness training in a randomized controlled trial.

    Science.gov (United States)

    Lindsay, Emily K; Young, Shinzen; Smyth, Joshua M; Brown, Kirk Warren; Creswell, J David

    2018-01-01

    Mindfulness interventions, which train practitioners to monitor their present-moment experience with a lens of acceptance, are known to buffer stress reactivity. Little is known about the active mechanisms driving these effects. We theorize that acceptance is a critical emotion regulation mechanism underlying mindfulness stress reduction effects. In this three-arm parallel trial, mindfulness components were dismantled into three structurally equivalent 15-lesson smartphone-based interventions: (1) training in both monitoring and acceptance (Monitor+Accept), (2) training in monitoring only (Monitor Only), or (3) active control training (Coping control). 153 stressed adults (mean age=32years; 67% female; 53% white, 21.5% black, 21.5% Asian, 4% other race) were randomly assigned to complete one of three interventions. After the intervention, cortisol, blood pressure, and subjective stress reactivity were assessed using a modified Trier Social Stress Test. As predicted, Monitor+Accept training reduced cortisol and systolic blood pressure reactivity compared to Monitor Only and control trainings. Participants in all three conditions reported moderate levels of subjective stress. This study provides the first experimental evidence that brief smartphone mindfulness training can impact stress biology, and that acceptance training drives these effects. We discuss implications for basic and applied research in contemplative science, emotion regulation, stress and coping, health, and clinical interventions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Reactive trace gas emissions from stressed plants: a poorly characterized major source of atmospheric volatiles

    Science.gov (United States)

    Niinemets, Ülo

    2017-04-01

    Vegetation constitutes the greatest source of reactive volatile organic compounds in the atmosphere. The current emission estimates primarily rely on constitutive emissions that are present only in some plant species. However, all plant species can be induced to emit reactive volatiles by different abiotic and biotic stresses, but the stress-dependent emissions have been largely neglected in emission measurements and models. This presentation provides an overview of systematic screening of stress-dependent volatile emissions from a broad range of structurally and physiologically divergent plant species from temperate to tropical ecosystems. Ozone, heat, drought and wounding stress were the abiotic stresses considered in the screening, while biotic stress included herbivory, chemical elicitors simulating herbivory and fungal infections. The data suggest that any moderate to severe stress leads to significant emissions of a rich blend of volatiles, including methanol, green leaf volatiles (the lipoxygenase pathway volatiles, dominated by C6 aldehydes, alcohols and derivatives), different mono- and sesquiterpenes and benzenoids. The release of volatiles occurs in stress severity-dependent manner, although the emission responses are often non-linear with more severe stresses resulting in disproportionately greater emissions. Stress volatile release is induced in both non-constitutive and constitutive volatile emitters, whereas the rate of constitutive volatile emissions in constitutive emitters is often reduced under environmental and biotic stresses. Given that plants in natural conditions often experience stress, this analysis suggests that global volatile emissions have been significantly underestimated. Furthermore, in globally changing hotter climates, the frequency and severity of both abiotic and biotic stresses is expected to increase. Thus, the stress-induced volatile emissions are predicted to play a dominant role in plant-atmosphere interactions in near

  3. Physiological stress reactivity in human pregnancy--a review.

    NARCIS (Netherlands)

    Weerth, C. de; Buitelaar, J.K.

    2005-01-01

    Prenatal maternal stress has been found to have long-lasting effects on the behavioral and physiological development of the offspring. These programming effects on the fetus would be physiologically mediated through heightened and/or abnormal activity of the maternal sympathetic-adrenal-medullary

  4. Physiological stress reactivity in human pregnancy - a review

    NARCIS (Netherlands)

    Weerth, C. de; Buitelaar, J.K.

    2005-01-01

    Prenatal maternal stress has been found to have long-lasting effects on the behavioral and physiological development of the offspring. These programming effects on the fetus would be physiologically mediated through heightened and/or abnormal activity of the maternal sympathetic-adrenal-medullary

  5. Length scale of secondary stresses in fracture and fatigue

    International Nuclear Information System (INIS)

    Dong, P.

    2008-01-01

    In an attempt to provide a consistent framework for the analysis and treatment of secondary stresses associated with welding and thermal loading in the context of fracture mechanics, this paper starts with an effective stress characterization procedure by introducing a length-scale concept. With it, a traction-based stress separation procedure is then presented to provide a consistent characterization of stresses from various sources based on their length scale. Their relative contributions to fracture driving force are then quantified in terms of their characteristic length scales. Special attention is given to the implications of the length-scale argument on both analysis and treatment of welding residual stresses in fracture assessment. A series of examples is provided to demonstrate how the present developments can be applied for treating not only secondary stresses but also externally applied stresses, as well as their combined effects on the structural integrity of engineering components

  6. Development of the Children's Scale of Hostility and Aggression: Reactive/Proactive (C-SHARP)

    Science.gov (United States)

    Farmer, Cristan A.; Aman, Michael G.

    2009-01-01

    Whereas some scales exist for assessing aggression in typically developing children, they do not give a detailed analysis, and none is available for populations with developmental disabilities (DD). Parents of 365 children with DD completed the Children's Scale of Hostility and Aggression: Reactive/Proactive (C-SHARP), which surveys the severity…

  7. Executive functioning performance predicts subjective and physiological acute stress reactivity: preliminary results.

    Science.gov (United States)

    Hendrawan, Donny; Yamakawa, Kaori; Kimura, Motohiro; Murakami, Hiroki; Ohira, Hideki

    2012-06-01

    Individual differences in baseline executive functioning (EF) capacities have been shown to predict state anxiety during acute stressor exposure. However, no previous studies have clearly demonstrated the relationship between EF and physiological measures of stress. The present study investigated the efficacy of several well-known EF tests (letter fluency, Stroop test, and Wisconsin Card Sorting Test) in predicting both subjective and physiological stress reactivity during acute psychosocial stress exposure. Our results show that letter fluency served as the best predictor for both types of reactivity. Specifically, the higher the letter fluency score, the lower the acute stress reactivity after controlling for the baseline stress response, as indicated by lower levels of state anxiety, negative mood, salivary cortisol, and skin conductance. Moreover, the predictive power of the letter fluency test remained significant for state anxiety and cortisol indices even after further adjustments for covariates by adding the body mass index (BMI) as a covariate. Thus, good EF performance, as reflected by high letter fluency scores, may dampen acute stress responses, which suggests that EF processes are directly associated with aspects of stress regulation. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Scales tell a story on the stress history of fish.

    Science.gov (United States)

    Aerts, Johan; Metz, Juriaan Rogier; Ampe, Bart; Decostere, Annemie; Flik, Gert; De Saeger, Sarah

    2015-01-01

    Fish faced with stressful stimuli launch an endocrine stress response through activation of the hypothalamic-pituitary-interrenal (HPI-) axis to release cortisol into the blood. Scientifically validated biomarkers to capture systemic cortisol exposure over longer periods of time are of utmost importance to assess chronic stress in governmental, wildlife, aquaculture and scientific settings. Here we demonstrate that cortisol in scales of common carp (Cyprinus carpio L.) is the long-sought biomarker for chronic stress. Undisturbed (CTR) and daily stressed (STRESS) carp were compared. Dexamethasone (DEX) or cortisol (CORT) fed fish served as negative and positive controls, respectively. Scale cortisol was quantified with a validated ultra-performance liquid chromatography tandem mass spectrometry method. An increase in scale cortisol content was found in STRESS and CORT but not in CTR and DEX fish. Scale cortisol content reflects its accumulation in a stressor and time dependent manner and validates the scale cortisol content as biomarker for chronic stress. Plasma analyses confirmed that (i) CTR, DEX and CORT treatments were effective, (ii) plasma cortisol of STRESS fish showed no signs of chronic HPI-axis activation, and (iii) plasma cortisol is a poor predictor for chronic stress. The expression of HPI key genes crf, pomc, and star were up-regulated in STRESS fish in the absence of a plasma cortisol response, as was the target gene of cortisol encoding subunit α1 of the Na+/K+-ATPase in gills. When lost, scales of fish regenerate fast. Regenerated scales corroborate our findings, offering (i) unsurpassed time resolution for cortisol incorporation and as such for stressful events, and (ii) the possibility to investigate stress in a well defined and controlled environment and time frame creating novel opportunities for bone physiological research. We conclude that the cortisol content in ontogenetic and regenerated scales is an innovative biomarker for chronic

  9. Anticipation of smoking sufficiently dampens stress reactivity in nicotine-deprived smokers.

    Science.gov (United States)

    Bradford, Daniel E; Curtin, John J; Piper, Megan E

    2015-02-01

    Most smokers attempting to quit will relapse, even when using evidence-based cessation treatment. This illustrates the need for better understanding of the relapse process to thereby improve cessation treatments. Although the impact of stress sensitivity on relapse is clear, little research has precisely examined stress reactivity in addicted individuals. Further, most research on relapse focuses on affect surrounding self-administration, and does not address potentially important preconsumption processes such as anticipation of use. We examined the effects of anticipation and actual smoking on stress reactivity in 34 deprived smokers withdrawn for 24 hr and 37 nondeprived smokers, with 37 nonsmoker controls. Using a cued shock stressor task, we measured stress reactivity via startle potentiation and self-reported anxiety. After completing the task once, smokers anticipated smoking a cigarette resting in front of them while they completed the task a second time. Smokers then smoked before completing the task a third and final time. Nonsmokers anticipated and drank water as a control. Anticipation of smoking significantly attenuated both startle potentiation and self-reported anxiety to shock cues for deprived smokers relative to nondeprived smokers. Smokers' stress reactivity was not reduced by smoking beyond the prior effect of anticipation. These results suggest that anticipation, rather than actual drug consumption, may drive the primary reinforcing effect of reduced stress reactivity in smoking. Future research is needed to understand this effect of anticipation on drug use and to determine whether anticipation would make an effective intervention target for addiction and other psychopathology that exhibits increased stress sensitivity. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

  10. Late-Onset Cognitive Impairments after Early-Life Stress Are Shaped by Inherited Differences in Stress Reactivity

    Science.gov (United States)

    McIlwrick, Silja; Pohl, Tobias; Chen, Alon; Touma, Chadi

    2017-01-01

    Early-life stress (ELS) has been associated with lasting cognitive impairments and with an increased risk for affective disorders. A dysregulation of the hypothalamus-pituitary-adrenal (HPA) axis, the body’s main stress response system, is critically involved in mediating these long-term consequences of adverse early-life experience. It remains unclear to what extent an inherited predisposition for HPA axis sensitivity or resilience influences the relationship between ELS and cognitive impairments, and which neuroendocrine and molecular mechanisms may be involved. To investigate this, we exposed animals of the stress reactivity mouse model, consisting of three independent lines selectively bred for high (HR), intermediate (IR), or low (LR) HPA axis reactivity to a stressor, to ELS and assessed their cognitive performance, neuroendocrine function and hippocampal gene expression in early and in late adulthood. Our results show that HR animals that were exposed to ELS exhibited an HPA axis hyper-reactivity in early and late adulthood, associated with cognitive impairments in hippocampus-dependent tasks, as well as molecular changes in transcript levels involved in the regulation of HPA axis activity (Crh) and in neurotrophic action (Bdnf). In contrast, LR animals showed intact cognitive function across adulthood, with no change in stress reactivity. Intriguingly, LR animals that were exposed to ELS even showed significant signs of enhanced cognitive performance in late adulthood, which may be related to late-onset changes observed in the expression of Crh and Crhr1 in the dorsal hippocampus of these animals. Collectively, our findings demonstrate that the lasting consequences of ELS at the level of cognition differ as a function of inherited predispositions and suggest that an innate tendency for low stress reactivity may be protective against late-onset cognitive impairments after ELS. PMID:28261058

  11. Impact of Sleep Quality on Amygdala Reactivity, Negative Affect, and Perceived Stress

    Science.gov (United States)

    Prather, Aric A.; Bogdan, Ryan; Ahmad R. Hariri, PhD

    2013-01-01

    Objective Research demonstrates a negative impact of sleep disturbance on mood and affect; however, the biological mechanisms mediating these links are poorly understood. Amygdala reactivity to negative stimuli has emerged as one potential pathway. Here, we investigate the influence of self-reported sleep quality on associations between threat-related amygdala reactivity and measures of negative affect and perceived stress. Methods Analyses on data from 299 participants (125 men, 50.5% white, mean [standard deviation] age = 19.6 [1.3] years) who completed the Duke Neurogenetics Study were conducted. Participants completed several self-report measures of negative affect and perceived stress. Threat-related (i.e., angry and fearful facial expressions) amygdala reactivity was assayed using blood oxygen level–dependent functional magnetic resonance imaging. Global sleep quality was assessed using the Pittsburgh Sleep Quality Index. Results Amygdala reactivity to fearful facial expressions predicted greater depressive symptoms and higher perceived stress in poor (β values = 0.18–1.86, p values .05). In sex-specific analyses, men reporting poorer global sleep quality showed a significant association between amygdala reactivity and levels of depression and perceived stress (β values = 0.29–0.44, p values < .05). In contrast, no significant associations were observed in men reporting good global sleep quality or in women, irrespective of sleep quality. Conclusions This study provides novel evidence that self-reported sleep quality moderates the relationships between amygdala reactivity, negative affect, and perceived stress, particularly among men. PMID:23592753

  12. Scaling of reactor cavity wall loads and stresses

    International Nuclear Information System (INIS)

    Bohachevsky, I.O.

    1977-11-01

    Scalings of reactor cavity wall loads and stresses are determined by deriving an analytic expression in terms of relevant parameters for each loading induced in the reactor cavity walls by fuel pellet microexplosion and by deriving associated expressions relating resulting stresses to shell thicknesses. Also identified are problems that require additional investigations to obtain satisfactory explicit stress estimates for the reactor cavity walls

  13. The Effects of Training Contingency Awareness During Attention Bias Modification on Learning and Stress Reactivity.

    Science.gov (United States)

    Lazarov, Amit; Abend, Rany; Seidner, Shiran; Pine, Daniel S; Bar-Haim, Yair

    2017-09-01

    Current attention bias modification (ABM) procedures are designed to implicitly train attention away from threatening stimuli with the hope of reducing stress reactivity and anxiety symptoms. However, the mechanisms underlying effective ABM delivery are not well understood, with awareness of the training contingency suggested as one possible factor contributing to ABM efficacy. Here, 45 high-anxious participants were trained to divert attention away from threat in two ABM sessions. They were randomly assigned to one of three training protocols: an implicit protocol, comprising two standard implicit ABM training sessions; an explicit protocol, comprising two sessions with explicit instruction as to the attention training contingency; and an implicit-explicit protocol, in which participants were not informed of the training contingency in the first ABM session and informed of it at the start of the second session. We examined learning processes and stress reactivity following a stress-induction task. Results indicate that relative to implicit instructions, explicit instructions led to stronger learning during the first training session. Following rest, the explicit and implicit groups exhibited consolidation-related improvement in performance, whereas no such improvement was noted for the implicit-explicit group. Finally, although stress reactivity was reduced after training, contingency awareness did not yield a differential effect on stress reactivity measured using both self-reports and skin conductance, within and across sessions. These results suggest that explicit ABM administration leads to greater initial learning during the training protocol while not differing from standard implicit administration in terms of off-line learning and stress reactivity. Copyright © 2017. Published by Elsevier Ltd.

  14. Predicting developmental changes in internalizing symptoms: examining the interplay between parenting and neuroendocrine stress reactivity.

    Science.gov (United States)

    Kuhlman, Kate R; Olson, Sheryl L; Lopez-Duran, Nestor L

    2014-07-01

    In this study, we examined whether parenting and HPA-axis reactivity during middle childhood predicted increases in internalizing symptoms during the transition to adolescence, and whether HPA-axis reactivity mediated the impact of parenting on internalizing symptoms. The study included 65 children (35 boys) who were assessed at age 5, 7, and 11. Parenting behaviors were assessed via parent report at age 5 and 11. The child's HPA-axis reactivity was measured at age 7 via a stress task. Internalizing symptoms were measured via teacher reports at age 5 and 11. High maternal warmth at age 5 predicted lower internalizing symptoms at age 11. Also, high reported maternal warmth and induction predicted lower HPA-axis reactivity. Additionally, greater HPA-axis reactivity at age 7 was associated with greater increases in internalizing symptoms from age 5 to 11. Finally, the association between age 5 maternal warmth and age 11 internalizing symptoms was partially mediated by lower cortisol in response to the stress task. Thus, parenting behaviors in early development may influence the physiological stress response system and therefore buffer the development of internalizing symptoms during preadolescence when risk for disorder onset is high. © 2013 Wiley Periodicals, Inc.

  15. Resilience, work engagement and stress reactivity in a middle-aged manual worker population.

    Science.gov (United States)

    Black, Julie K; Balanos, George M; Whittaker Previously Phillips, Anna C

    2017-06-01

    Work stress is a growing problem in Europe. Together, the negative physiological effect of stress on health, and increasing age increases the risk of developing cardiovascular disease in those aged over 50years. Therefore, identifying older workers who may be at risk of work-related stress, and its physiological effects, is key to promoting their health and wellbeing in the workforce. The present study examined the relationship between perceived psychological resilience and work-related factors (work engagement and presenteeism) and the physiological response to acute psychological stress in older manual workers in the UK. Thirty-one participants, mean (SD) age 54.9 (3.78)years reported perceived levels of resilience, work engagement, and presenteeism using standardized questionnaires. Cardiovascular measurements (heart rate (HR) and blood pressure (BP) and salivary cortisol were used to assess their physiological response to an acute psychological stress task. Resilience was not associated with work-related factors or reactivity. However, workers with higher work engagement showed lower SBP (p=0.02) and HR (p=0.001) reactivity than those with lower work engagement. Further, those with higher sickness presenteeism also had higher HR reactivity (p=0.03). This suggests a potential pathway by which higher work stress might contribute to the risk of future cardiovascular disease. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Energy scaling of focused discharges with enhanced reactivity

    International Nuclear Information System (INIS)

    Bortolotti, A.; Broglio, L.; Brzosko, J.S.; Dechiara, P.; Kilic, H.; Mezzetti, F.; Montanari, T.; Nardi, V.; Powell, C.; Woo, H.

    1993-01-01

    The neutron yield per pulse (Y n ) from D + D reactions, the thickness (δ) and speed (v s ) of the leading plasma current sheath in the electrode gap and the multiplicity (υ) of current sheaths in one discharge are monitored in two plasma focus machines operating at different levels of the capacitor bank energy 5 kJ ≤ W ≤ 10 kJ and 12 kJ ≤ W ≤ 30 kJ, respectively .The time spacing (Δt) between leading (CS 1 ) and trailing (CS 2 ) current sheath is also recorded up to a CS distance r = 1.7 cm from the center electrode (anode) axis. The scaling of Y n ∼ A W 2 is tested for PF-Mather-geometry machines with a field distortion element (FDE) inserted at the breech side of the electrode gap which increases Y n (i.e. the constant A) by a factor ≥ 5, above the Y n value of the same machines, operating under identical conditions, but without FDE, Similar scaling tests on Y n = Y n (W, δ, V s , υ, Δt) confirm that Δt is one of the controlling parameters with strong effects on Y n . Spectra and intensities of ion and ion cluster emission from the pinch are also routinely observed in each discharge, in order to determine the relative weight of each controlling parameter for a variety of PF applications

  17. Long-Term Effectiveness of Stress Management at Work: Effects of the Changes in Perceived Stress Reactivity on Mental Health and Sleep Problems Seven Years Later.

    Science.gov (United States)

    Herr, Raphael M; Barrech, Amira; Riedel, Natalie; Gündel, Harald; Angerer, Peter; Li, Jian

    2018-02-03

    The reduction of stress reactivity resulting from stress management interventions prevents disorders and improves mental health, however, its long-term sustainability has been little examined. The objective of this study was, therefore, to determine the effectiveness of a stress management intervention, designed to improve stress reactivity, for mental health and sleep problems seven years later, using longitudinal data from 101 male industrial workers. Linear regressions estimated the adjusted effects of the changes in stress reactivity in general as well as in its six subdimensions (work overload, social conflict, social stress, failure at work, and anticipatory and prolonged reactivity) on depression, anxiety, and sleep problems seven years later. The improvement of the prolonged reactivity had positive effects on depression, anxiety, and sleep problems (unstandardized regression coefficients [ Bs ] ≥ 0.35, all p -values ≤ 0.01). Depression and sleep problems were further improved by a reduction of the reactivity to social conflicts ( Bs ≥ 0.29, p -values stress reactivity resulting from a work stress intervention was effective and generally long-lasting in preventing mental health and sleep problems. The reduction of the prolonged reactivity seems of particular importance and efficient in inhibiting negative stress manifestations.

  18. SKA2 Methylation is Involved in Cortisol Stress Reactivity and Predicts the Development of Post-Traumatic Stress Disorder (PTSD) After Military Deployment

    OpenAIRE

    Boks, Marco P; Rutten, Bart P F; Geuze, Elbert; Houtepen, Lotte C; Vermetten, Eric; Kaminsky, Zachary; Vinkers, Christiaan H

    2015-01-01

    Genomic variation in the SKA2 gene has recently been identified as a promising suicide biomarker. In light of its role in glucocorticoid receptor transactivation, we investigated whether SKA2 DNA methylation influences cortisol stress reactivity and is involved in the development of post-traumatic stress disorder (PTSD). Increased SKA2 methylation was significantly associated with lower cortisol stress reactivity in 85 healthy individuals exposed to the Trier Social Stress Test (B=?173.40, t=...

  19. Dynamic Reactive Power Compensation of Large Scale Wind Integrated Power System

    DEFF Research Database (Denmark)

    Rather, Zakir Hussain; Chen, Zhe; Thøgersen, Paul

    2015-01-01

    wind turbines especially wind farms with additional grid support functionalities like dynamic support (e,g dynamic reactive power support etc.) and ii) refurbishment of existing conventional central power plants to synchronous condensers could be one of the efficient, reliable and cost effective option......Due to progressive displacement of conventional power plants by wind turbines, dynamic security of large scale wind integrated power systems gets significantly compromised. In this paper we first highlight the importance of dynamic reactive power support/voltage security in large scale wind...... integrated power systems with least presence of conventional power plants. Then we propose a mixed integer dynamic optimization based method for optimal dynamic reactive power allocation in large scale wind integrated power systems. One of the important aspects of the proposed methodology is that unlike...

  20. Laterality strength is linked to stress reactivity in Port Jackson sharks (Heterodontus portusjacksoni).

    Science.gov (United States)

    Byrnes, Evan E; Vila Pouca, Catarina; Brown, Culum

    2016-05-15

    Cerebral lateralization is an evolutionarily deep-rooted trait, ubiquitous among the vertebrates and present even in some invertebrates. Despite the advantages of cerebral lateralization in enhancing cognition and facilitating greater social cohesion, large within population laterality variation exists in many animal species. It is proposed that this variation is maintained due links with inter-individual personality trait differences. Here we explored for lateralization in Port Jackson sharks (Heterodontus portusjacksoni) using T-maze turn and rotational swimming tasks. Additionally, we explored for a link between personality traits, boldness and stress reactivity, and cerebral lateralization. Sharks demonstrated large individual and sex biased laterality variation, with females demonstrating greater lateralization than males overall. Stress reactivity, but not boldness, was found to significantly correlate with lateralization strength. Stronger lateralized individuals were more reactive to stress. Demonstrating laterality in elasmobranchs for the first time indicates ancient evolutionary roots of vertebrate lateralization approximately 240 million years old. Greater lateralization in female elasmobranchs may be related enhancing females' ability to process multiple stimuli during mating, which could increase survivability and facilitate insemination. Despite contrasting evidence in teleost fishes, the results of this study suggest that stress reactivity, and other personality traits, may be linked to variation in lateralization. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Off-Time Pubertal Timing Predicts Physiological Reactivity to Postpuberty Interpersonal Stress

    Science.gov (United States)

    Smith, Anne Emilie; Powers, Sally I.

    2009-01-01

    We investigated associations between retrospectively assessed timing of pubertal development, interpersonal interactions, and hypothalamic-pituitary-adrenal axis reactivity to an interpersonal stress task in 110 young adult women. Participants provided salivary cortisol samples at points prior and subsequent to a video-taped conflict discussion…

  2. Neuroticism and extraversion in relation to physiological stress reactivity during adolescence

    NARCIS (Netherlands)

    Evans, Brittany E.; Stam, Jacqueline; Huizink, Anja C.; Willemen, Agnes M.; Westenberg, P. Michiel; Branje, Susan; Meeus, W.H.J.; Koot, Hans M.; van Lier, Pol A. C.

    2016-01-01

    The current study examined mean level and change in extraversion and neuroticism across adolescence in relation to physiological stress reactivity to social evaluation. Adolescents (n=327) from the Dutch general population reported on personality measures at five annual assessments. At age 17 years,

  3. Hypothalamic-pituitary-adrenal axis reactivity to social stress and adolescent cannabis use: the TRAILS study

    NARCIS (Netherlands)

    Prince van Leeuwen, A.; Creemers, H.E.; Greaves-Lord, K.; Verhulst, F.C.; Ormel, J.; Huizink, A.C.

    2011-01-01

    Aims: To investigate the relationship of life-time and repeated cannabis use with hypothalamic-pituitary-adrenal (HPA) axis reactivity to social stress in a general population sample of adolescents. Design: Adolescents who reported life-time or repeated cannabis use, life-time or repeated tobacco

  4. Hypothalamic-pituitary-adrenal axis reactivity to social stress and adolescent cannabis use : the TRAILS study

    NARCIS (Netherlands)

    van Leeuwen, Andrea Prince; Creemers, Hanneke E.; Greaves-Lord, Kirstin; Verhulst, Frank C.; Ormel, Johan; Huizink, Anja C.

    Aims To investigate the relationship of life-time and repeated cannabis use with hypothalamic-pituitary-adrenal (HPA) axis reactivity to social stress in a general population sample of adolescents. Design Adolescents who reported life-time or repeated cannabis use, life-time or repeated tobacco use

  5. Cortisol Reactivity to Social Stress as a Mediator of Early Adversity on Risk and Adaptive Outcomes

    Science.gov (United States)

    Conradt, Elisabeth; Abar, Beau; Lester, Barry M.; LaGasse, Linda L.; Shankaran, Seetha; Bada, Henrietta; Bauer, Charles R.; Whitaker, Toni M.; Hammond, Jane A.

    2014-01-01

    Children chronically exposed to stress early in life are at increased risk for maladaptive outcomes, though the physiological mechanisms driving these effects are unknown. Cortisol reactivity was tested as a mediator of the relation between prenatal substance exposure and/or early adversity on adaptive and maladaptive outcomes. Data were drawn…

  6. Multi-scales modeling of reactive transport mechanisms. Impact on petrophysical properties during CO2 storage

    International Nuclear Information System (INIS)

    Varloteaux, C.

    2012-01-01

    The geo-sequestration of carbon dioxide (CO 2 ) is an attractive option to reduce the emission of greenhouse gases. Within carbonate reservoirs, acidification of brine in place can occur during CO 2 injection. This acidification leads to mineral dissolution which can modify the transport properties of a solute in porous media. The aim of this study is to quantify the impact of reactive transport on a solute distribution and on the structural modification induced by the reaction from the pore to the reservoir scale. This study is focused on reactive transport problem in the case of single phase flow in the limit of long time. To do so, we used a multi-scale up-scaling method that takes into account (i) the local scale, where flow, reaction and transport are known; (ii) the pore scale, where the reactive transport is addressed by using averaged formulation of the local equations; (iii) the Darcy scale (also called core scale), where the structure of the rock is taken into account by using a three-dimensions network of pore-bodies connected by pore-throats; and (iv) the reservoir scale, where physical phenomenon, within each cell of the reservoir model, are taken into account by introducing macroscopic coefficients deduced from the study of these phenomenon at the Darcy scale, such as the permeability, the apparent reaction rate, the solute apparent velocity and dispersion. (author)

  7. Parenting stress and externalizing behavior symptoms in children: the impact of emotional reactivity.

    Science.gov (United States)

    Buodo, Giulia; Moscardino, Ughetta; Scrimin, Sara; Altoè, Gianmarco; Palomba, Daniela

    2013-12-01

    This study investigated whether the parenting stress-child externalizing behavior link is moderated by children's emotional reactivity, as indexed by skin conductance responses (SCRs). Participants were 61 children aged 9-12 years and their mothers. Mothers completed measures of parenting stress and their children's externalizing symptoms; children also reported on their externalizing behavior. Children's SCRs were assessed during the viewing of standardized pleasant, unpleasant, and neutral pictures. Cluster analysis on SCRs identified two groups, labeled Lower SCRs and Higher SCRs. Regression analyses indicated that among children with lower SCRs, those exposed to increased parenting stress reported more externalizing symptoms, whereas those who experienced low parenting stress reported similar rates of externalizing problems as children with higher SCRs. No effect of parenting stress emerged for children with higher SCRs. Findings suggest that higher parenting stress renders children with lower, as opposed to higher, SCRs to emotional stimuli more vulnerable to externalizing problems.

  8. Blunted hypothalamo-pituitary adrenal axis response to predator odor predicts high stress reactivity.

    Science.gov (United States)

    Whitaker, Annie M; Gilpin, Nicholas W

    2015-08-01

    Individuals with trauma- and stress-related disorders exhibit increases in avoidance of trauma-related stimuli, heightened anxiety and altered neuroendocrine stress responses. Our laboratory uses a rodent model of stress that mimics the avoidance symptom cluster associated with stress-related disorders. Animals are classified as 'Avoiders' or 'Non-Avoiders' post-stress based on avoidance of predator-odor paired context. Utilizing this model, we are able to examine subpopulation differences in stress reactivity. Here, we used this predator odor model of stress to examine differences in anxiety-like behavior and hypothalamo-pituitary adrenal (HPA) axis function in animals that avoid a predator-paired context relative to those that do not. Rats were exposed to predator odor stress paired with a context and tested for avoidance (24h and 11days), anxiety-like behavior (48h and 5days) and HPA activation following stress. Control animals were exposed to room air. Predator odor stress produced avoidance in approximately 65% of the animals at 24h that persisted 11days post-stress. Both Avoiders and Non-Avoiders exhibited a heightened anxiety-like behavior at 48h and 5days post-stress when compared to unstressed Controls. Non-Avoiders exhibited significant increases in circulating adrenocorticotropin hormone (ACTH) and corticosterone (CORT) concentrations immediately following predator odor stress compared to Controls and this response was significantly attenuated in Avoiders. There was an inverse correlation between circulating ACTH/CORT concentrations and avoidance, indicating that lower levels of ACTH/CORT predicted higher levels of avoidance. These results suggest that stress effects on HPA stress axis activation predict long-term avoidance of stress-paired stimuli, and build on previous data showing the utility of this model for exploring the neurobiological mechanisms of trauma- and stress-related disorders. Copyright © 2015. Published by Elsevier Inc.

  9. Biological Sensitivity to Context: The Interactive Effects of Stress Reactivity and Family Adversity on Socioemotional Behavior and School Readiness

    Science.gov (United States)

    Obradovic, Jelena; Bush, Nicole R.; Stamperdahl, Juliet; Adler, Nancy E.; Boyce, W. Thomas

    2010-01-01

    This study examined the direct and interactive effects of stress reactivity and family adversity on socioemotional and cognitive development in three hundred and thirty-eight 5- to 6-year-old children. Neurobiological stress reactivity was measured as respiratory sinus arrhythmia and salivary cortisol responses to social, cognitive, sensory, and…

  10. Reliability of the factor structure of the Multidimensional Scale of Interpersonal Reactivity (EMRI

    Directory of Open Access Journals (Sweden)

    Nilton S. Formiga

    2013-10-01

    Full Text Available This study aims to check the internal consistency and factor structure evaluative of the empathy scale in a high school and college sample in the state of Minas Gerais. The instruments that measure empathy can be easily found, however, of the existing, just multidimensional scale of interpersonal reactivity (Emri is the theoretical framework that has far more and better organized, and the scale that is most commonly used to assess this construct. Participated 488 subjects, male and female, with ages from 14-54 years old, distributed in primary and college levels in Patrocínio-MG composed this study sample. The subjects answered the Multidimensional Scale of Interpersonal Reactivity and socio-demographic data. From an equation analysis and structural modeling were observed psychometric indicators that assured the structural consistency of the scale, promoting in the security of the measure theoretical construct of empathy.

  11. Social anxiety and disordered eating: The influence of stress reactivity and self-esteem.

    Science.gov (United States)

    Ciarma, Jessica Lyn; Mathew, Jaya Miriam

    2017-08-01

    While previous research indicates a strong link between social anxiety and disordered eating, more research is needed in order to understand the mechanisms that underlie this relationship. Given that stress is often implicated in disordered eating, it was hypothesised that ones reaction to stress (i.e. stress reactivity) would mediate the relationship between social anxiety and disordered eating. Similarly, given that low self-esteem is commonly reported in both those with social anxiety and eating disorders, it was hypothesised that self-esteem would also mediate the relationship between social anxiety and disordered eating. In order to test this, an online survey measuring social anxiety, disordered eating, stress reactivity and self-esteem, was administered to 282 participants in the community, aged between 18 and 35years. Results showed that self-esteem and a reactivity to stress during social conflict - but not during negative social evaluations - partially mediated the relationship between social anxiety and disordered eating. These findings demonstrate that low self-esteem and interpersonal conflict are powerful mechanisms that can maintain eating disorder psychopathology in those who are socially anxious. This highlights the importance of ensuring that these mechanisms are sufficiently addressed in eating disorder prevention and treatment programs. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Combined exercise circuit session acutely attenuates stress-induced blood pressure reactivity in healthy adults

    Directory of Open Access Journals (Sweden)

    Sérgio R. Moreira

    2014-03-01

    Full Text Available Objective: To investigate the blood pressure (BP responses to cardiovascular stress test after a combined exercise circuit session at moderate intensity. Method: Twenty individuals (10 male/10 fem; 33.4± 6.9 years; 70.2± 15.8 kg; 170.4± 11.5 cm; 22.3± 6.8% body fat were randomized in a different days to control session with no exercise or exercise session consisting of 3 laps of the following circuit: knee extension, bench press, knee flexion, rowing in the prone position, squats, shoulder press, and 5 min of aerobic exercise at 75-85% of age-predicted maximum heart rate and/or 13 on the Borg Rating of Perceived Exertion [scale of 6 to 20]. The sets of resistance exercise consisted of 15 repetitions at ~50% of the estimated 1 repetition maximum test. Systolic blood pressure (SBP and diastolic blood pressure (DBP were measured at rest and during 1h of recovery in both experimental sessions. After that, blood pressure reactivity (BPR was evaluated using the Cold Pressor Test. Results: During 1h of exercise recovery, there was a reduction in SBP (3-6 mmHg and DBP (2-5 mmHg in relation to pre-session rest (p<0.01, while this reduction was not observed in the control session. A decline in BPR (4-7 mmHg; p<0.01 was observed 1h post-exercise session, but not in the control session. Post-exercise reductions in SBP and DBP were significantly correlated with BPR reductions (r=0.50-0.45; p<0.05. Conclusion: A combined exercise circuit session at moderate intensity promoted subsequent post-exercise hypotension and acutely attenuated BPR in response to a cardiovascular stress test. In addition, the post-exercise BP reduction was correlated with BPR attenuation in healthy adults of both genders.

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

    Science.gov (United States)

    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.

  14. Construction and preliminary validation of the Barcelona Immigration Stress Scale.

    Science.gov (United States)

    Tomás-Sábado, Joaquín; Qureshi, Adil; Antonin, Montserrat; Collazos, Francisco

    2007-06-01

    In the study of mental health and migration, an increasing number of researchers have shifted the focus away from the concept of acculturation towards the stress present in the migratory experience. The bulk of research on acculturative stress has been carried out in the United States, and thus the definition and measurement of the construct has been predicated on that cultural and demographic context, which is of dubious applicability in Europe in general, and Spain in particular. Further, some scales have focused on international students, which down-played the importance of the migratory process, because it deals with a special subset of people who are not formally immigrating. The Barcelona Immigration Stress Scale was developed to measure acculturative stress appropriate to immigrants in Spain, using expert and focus group review and has 42 items. The scale shows acceptable internal validity, and, consistent with other scales, suggests that immigration stress is a complex construct.

  15. The levonorgestrel-releasing intrauterine device potentiates stress reactivity.

    Science.gov (United States)

    Aleknaviciute, Jurate; Tulen, Joke H M; De Rijke, Yolanda B; Bouwkamp, Christian G; van der Kroeg, Mark; Timmermans, Mirjam; Wester, Vincent L; Bergink, Veerle; Hoogendijk, Witte J G; Tiemeier, Henning; van Rossum, Elisabeth F C; Kooiman, Cornelis G; Kushner, Steven A

    2017-06-01

    The levonorgestrel-releasing intrauterine device (LNG-IUD) is currently recommended as a first-line contraceptive with an exclusively local intrauterine influence. However, recent clinical trials have identified side effects of LNG-IUD that appear to be systemically mediated, including depressed mood and emotional lability. We performed two experimental studies and a cross-sectional study. For each study, women were included from three groups: LNG-IUD (0.02mg/24h), oral ethinylestradiol/levonorgestrel (0.03mg/0.15mg; EE30/LNG) and natural cycling (NC). Study 1-Salivary cortisol was measured at baseline and at defined intervals following the Trier Social Stress Test (TSST). Heart rate was monitored continuously throughout the TSST. Study 2-Salivary cortisol and serum total cortisol were evaluated relative to low-dose (1μg) adrenocorticotropic hormone (ACTH) administration. Study 3-Hair cortisol was measured as a naturalistic index of long-term cortisol exposure. Women using LNG-IUD had an exaggerated salivary cortisol response to the TSST (24.95±13.45 nmol/L, 95% CI 17.49-32.40), compared to EE30/LNG (3.27±2.83 nmol/L, 95% CI 1.71-4.84) and NC (10.85±11.03nmol/L, 95% CI 6.30-15.40) (Pcontraception induces a centrally-mediated sensitization of both autonomic and hypothalamic-pituitary-adrenal (HPA) axis responsivity. LNG-IUD sensitization of HPA axis responsivity was observed acutely under standardized laboratory conditions, as well as chronically under naturalistic conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. [Nursery Teacher's Stress Scale (NTSS): reliability and validity].

    Science.gov (United States)

    Akada, Taro

    2010-06-01

    This study describes the development and evaluation of the Nursery Teacher's Stress Scale (NTSS), which explores the relation between daily hassles at work and work-related stress. In Analysis 1, 29 items were chosen to construct the NTSS. Six factors were identified: I. Stress relating to child care; II. Stress from human relations at work; III. Stress from staff-parent relations; IV. Stress from lack of time; V. Stress relating to compensation; and VI. Stress from the difference between individual beliefs and school policy. All these factors had high degrees of internal consistency. In Analysis 2, the concurrent validity of the NTSS was examined. The results showed that the NTSS total scores were significantly correlated with the Job Stress Scale-Revised Version (job stressor scale, r = .68), the Pre-school Teacher-efficacy Scale (r = -.21), and the WHO-five Well-Being Index Japanese Version (r = -.40). Work stresses are affected by several daily hassles at work. The NTSS has acceptable reliability and validity, and can be used to improve nursery teacher's mental health.

  17. Behavioral phenotype relates to physiological differences in immunological and stress responsiveness in reactive and proactive birds.

    Science.gov (United States)

    Pusch, Elizabeth A; Navara, Kristen J

    2018-05-15

    It has now been demonstrated in many species that individuals display substantial variation in coping styles, generally separating into two major behavioral phenotypes that appear to be linked to the degree of physiological stress responsiveness. Laying hens are perfect examples of these dichotomous phenotypes; white laying hens are reactive, flighty, and exhibit large hormonal and behavioral responses to both acute and chronic stress, while brown laying hens are proactive, exploratory, and exhibit low hormonal and behavioral responses to stress. Given the linkages between stress physiology and many other body systems, we hypothesized that behavioral phenotype would correspond to additional physiological responses beyond the stress response, in this case, immunological responses. Because corticosterone is widely known to be immunosuppressive, we predicted that the reactive white hens would show more dampened immune responses than the proactive brown hens due to their exposure to higher levels of corticosterone throughout life. To assess immune function in white and brown hens, we compared febrile responses, corticosterone elevations, feed consumption, and egg production that occurred in response an injection of lipopolysaccharide (LPS) or saline, inflammatory responses to phytohemagglutinin (PHA) injection in the toe web, innate phagocytic activity in whole blood, and antibody responses to an injection of Sheep Red Blood Cells (SRBCs). Contrary to our predictions, white hens had significantly greater swelling of the toe web in response to PHA and showed a greater inhibition of feeding and reproductive output in response to LPS. These results indicated that reactive individuals are more reactive in both stress and immunological responsiveness. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. Stress-related anhedonia is associated with ventral striatum reactivity to reward and transdiagnostic psychiatric symptomatology

    Science.gov (United States)

    Corral-Frías, Nadia S.; Nikolova, Yuliya S.; Michalski, Lindsay J.; Baranger, David A.A.; Hariri, Ahmad R.; Bogdan, Ryan

    2015-01-01

    Background Early life stress (ELS) is consistently associated with increased risk for subsequent psychopathology. Individual differences in neural response to reward may confer vulnerability to stress-related psychopathology. Using data from the ongoing Duke Neurogenetics Study, the present study examined whether reward-related ventral striatum (VS) reactivity moderates the relationship between retrospectively reported ELS and anhedonic symptomatology. We further assessed whether individual differences in reward-related VS reactivity were associated with other depressive symptoms and problematic alcohol use via stress-related anhedonic symptoms and substance use-associated coping. Method Blood oxygen level-dependent functional magnetic resonance imaging (fMRI) was collected while participants (n = 906) completed a card-guessing task, which robustly elicits VS reactivity. ELS, anhedonic symptoms, other depressive symptoms, coping behavior, and alcohol use behavior were assessed with self-report questionnaires. Linear regressions were run to examine whether VS reactivity moderated the relationship between ELS and anhedonic symptoms. Structural equation models examined whether this moderation was indirectly associated with other depression symptoms and problematic alcohol use through its association with anhedonia. Results Analyses of data from 820 participants passing quality control procedures revealed that the VS × ELS interaction was associated with anhedonic symptoms (p = 0.011). Moreover, structural equation models indirectly linked this interaction to non-anhedonic depression symptoms and problematic alcohol use through anhedonic symptoms and substance-related coping. Conclusions These findings suggest that reduced VS reactivity to reward is associated with increased risk for anhedonia in individuals exposed to ELS. Such stress-related anhedonia is further associated with other depressive symptoms and problematic alcohol use through substance-related coping

  19. The conformity of BPP and vibroacoustic stimulation results in fetal non reactive non stress test

    Directory of Open Access Journals (Sweden)

    M. Modarres

    2006-08-01

    Full Text Available Background: The most frequently used test for evaluation of fetal health is the Non Stress Test (NST. Unfortunately it has a high incidence of false positive results. The combination of vibroacoustic stimulation with the NTS has been shown to reduce non reactive results. Methods: A tests assessment method was chosen with a simple randomized sampling. 40 pregnant women with non reactive NST in the first 20 minutes who received VAS in one of Tehran University's Hospitals were compared with BPP scores. A vibroacoustic stimulation was applied for a 3 seconds on the maternal abdomen and fallowed within 10 minutes.Data collection tools were NST, sonography instruments ,NST result paper, tooth brusher, watch, demographic questioner and check list. Data analysis was made by descriptive static and by using the Fisher's Exact Test (with level of significant at p<0/05. All statistical analysis were performed using an spss/win. Results: After VAS, 70% of non reactive tracing became reactive. All cases with fetal reactivity response after a VAS had a subsequent BPP score of 8 (negative predictive value of 100%. False positivity of VAS was lower than NST. Conclusion: VAS offers benefits, by decreasing the incidence of non reactive test and reducing test time. VAS lowers the rate of false positive NST. VAS is safe and allows more efficient of prenatal services. This test could be used as a rapid antepartum test to predict fetal well-being.

  20. Lattice Boltzmann based multicomponent reactive transport model coupled with geochemical solver for scale simulations

    NARCIS (Netherlands)

    Patel, R.A.; Perko, J.; Jaques, D.; De Schutter, G.; Ye, G.; Van Breugel, K.

    2013-01-01

    A Lattice Boltzmann (LB) based reactive transport model intended to capture reactions and solid phase changes occurring at the pore scale is presented. The proposed approach uses LB method to compute multi component mass transport. The LB multi-component transport model is then coupled with the

  1. Patterns of cortisol and alpha-amylase reactivity to psychosocial stress in maltreated women.

    Science.gov (United States)

    Mielock, Alyssa S; Morris, Matthew C; Rao, Uma

    2017-02-01

    Childhood maltreatment can trigger enduring changes in major stress response systems, particularly in the context of major depressive disorder (MDD). However, the relative impact of maltreatment versus MDD on hypothalamic-pituitary-adrenal axis and sympathetic-adrenal-medullary system stress reactivity is not well understood. This study examined salivary cortisol and alpha-amylase responses to the Trier Social Stress Test (TSST) in 26 maltreated (15 with current MDD) and 26 non-maltreated (17 with current MDD) women. Maltreated women showed greater anticipatory cortisol reactivity during the TSST protocol compared to non-maltreated women. Maltreated women also showed rapid deceleration in cortisol levels. Whereas non-maltreated women showed initial declines in alpha-amylase levels but rapidly increasing alpha-amylase levels during the TSST protocol, maltreated women did not exhibit changes in alpha-amylase levels during the TSST protocol. Contrary to expectation, MDD did not impact cortisol or alpha-amylase responses. The present study is limited by retrospective report of childhood maltreatment, cross-sectional design, and modest sample sizes. These findings suggest that childhood maltreatment plays a greater role driving alterations in cortisol and alpha-amylase stress reactivity than MDD. Understanding the biological embedding of maltreatment is critical for elucidating mechanisms linking these experiences to risk for negative mental and physical health outcomes. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Cortisol response mediates the effect of post-reactivation stress exposure on contextualization of emotional memories.

    Science.gov (United States)

    Bos, Marieke G N; Jacobs van Goethem, Tessa H; Beckers, Tom; Kindt, Merel

    2014-12-01

    Retrieval of traumatic experiences is often accompanied by strong feelings of distress. Here, we examined in healthy participants whether post-reactivation stress experience affects the context-dependency of emotional memory. First, participants studied words from two distinctive emotional categories (i.e., war and disease) presented against a category-related background picture. One day later, participants returned to the lab and received a reminder of the words of one emotional category followed by exposure to a stress task (Stress group, n=22) or a control task (Control group, n=24). Six days later, memory contextualization was tested using a word stem completion task. Half of the word stems were presented against the encoding context (i.e., congruent context) and the other half of the word stems were presented against the other context (i.e., incongruent context). The results showed that participants recalled more words in the congruent context than in the incongruent context. Interestingly, cortisol mediated the effect of stress exposure on memory contextualization. The stronger the post-reactivation cortisol response, the more memory performance relied on the contextual embedding of the words. Taken together, the current findings suggest that a moderate cortisol response after memory reactivation might serve an adaptive function in preventing generalization of emotional memories over contexts. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Reported Exposure and Emotional Reactivity to Daily Stressors: The Roles of Adult-Age and Global Perceived Stress

    OpenAIRE

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

    2008-01-01

    A central goal of daily stress research is to identify resilience and vulnerability factors associated with exposure and reactivity to daily stressors. The current study examined how age differences and global perceptions of stress relate to exposure and emotional reactivity to daily stressors. Sixty-seven younger (Mage = 20) and 116 older (Mage = 80) adults completed a daily stress diary and measures of positive and negative affect on 6 days over a 14 day period. Participants also completed ...

  4. Stress determination in thermally grown alumina scales using ruby luminescence

    Energy Technology Data Exchange (ETDEWEB)

    Renusch, D.; Veal, B.W.; Koshelev, I.; Natesan, K.; Grimsditch [Argonne National Lab., IL (United States); Hou, P.Y. [Lawrence Berkeley Lab., CA (United States)

    1996-06-01

    By exploiting the strain dependence of the ruby luminescence line, we have measured the strain in alumina scales thermally grown on Fe-Cr- Al alloys. Results are compared and found to be reasonably consistent with strains determined using x rays. Oxidation studies were carried out on alloys Fe - 5Cr - 28Al and Fe - 18Cr - 10Al (at.%). Significantly different levels of strain buildup were observed in scales on these alloys. Results on similar alloys containing a ``reactive element`` (Zr or Hf) in dilute quantity are also presented. Scales on alloys containing a reactive element (RE) can support significantly higher strains than scales on RE-free alloys. With the luminescence technique, strain relief associated with spallation thresholds is readily observed.

  5. A full-scale porous reactive wall for prevention of acid mine drainage

    International Nuclear Information System (INIS)

    Benner, S.G.; Blowes, D.W.; Ptacek, C.J.

    1997-01-01

    The generation and release of acidic drainage containing high concentrations of dissolved metals from decommissioned mine wastes is an environmental problem of international scale. A potential solution to many acid drainage problems is the installation of permeable reactive walls into aquifers affected by drainage water derived from mine waste materials. A permeable reactive wall installed into an aquifer impacted by low-quality mine drainage waters was installed in August 1995 at the Nickel Rim mine site near Sudbury, Ontario. The reactive mixture, containing organic matter, was designed to promote bacterially mediated sulfate reduction and subsequent metal sulfide precipitation. The reactive wall is installed to an average depth of 12 feet (3.6 m) and is 49 feet (15 m) long perpendicular to ground water flow. The wall thickness (flow path length) is 13 feet (4 m). Initial results, collected nine months after installation, indicate that sulfate reduction and metal sulfide precipitation is occurring. The reactive wall has effectively removed the capacity of the ground water to generate acidity on discharge to the surface. Calculations based on comparison to previously run laboratory column experiments indicate that the reactive wall has potential to remain effective for at least 15 years

  6. Cardiovascular reactivity in hypertensives: differential effect of expressing and inhibiting emotions during moments of interpersonal stress.

    Science.gov (United States)

    Lipp, Marilda E Novaes; Pereira, Márcia M Bignotto; Justo, Ana Paula; de Matos, Thania M Gomes

    2006-11-01

    This study investigated cardiovascular reactivity of hypertensive adults during periods of emotional stress. Two types of instructions were given at different moments, to the same subject, either to express or to suppress feelings during role-play. Expressing, but not inhibiting, emotions elicited significantly higher reactivity during responding to negative scenes, followed by responding during the positive interactions. Blood pressure increases in both expressing and inhibiting conditions, were also found during the instruction periods. Results indicated that socially demanding situations represent a stressor whose effects may vary depending on whether or not respondents regulate expression of emotions. It is suggested that the difficulty in expressing emotions found in some hypertensive individuals may have the function of controlling or reducing blood pressure reactivity.

  7. Emotional non-acceptance links early life stress and blunted cortisol reactivity to social threat.

    Science.gov (United States)

    Cărnuţă, Mihai; Crişan, Liviu G; Vulturar, Romana; Opre, Adrian; Miu, Andrei C

    2015-01-01

    Early life stress (ELS) has been recently associated with blunted cortisol reactivity and emotion dysregulation, but no study until now examined whether these characteristics are related. The main goal of this study was to examine the potential mediator role of emotion dysregulation in the relation between ELS and cortisol reactivity to social threat. Only women who were free of psychiatric and endocrine disorders, had regular menstrual cycle and did not use oral contraceptives were selected for this study (N=62). After filling in ELS and multidimensional emotion dysregulation measures, participants underwent the Trier Social Stress Test during which cortisol and autonomic responses were assessed. Most participants (85.5%) reported one or more major stressful events (i.e., physical abuse, sexual abuse, major parental conflicts, death of a family or close friend, severe illness) experienced before age 17. ELS was negatively associated with cortisol reactivity and positively associated with skin conductance level (SCL) reactivity, but it did not influence heart rate and respiratory sinus arrhythmia. In addition, ELS was positively related to emotional non-acceptance (i.e., a tendency to develop secondary emotional responses to one's negative emotions), and the latter was negatively related to cortisol responses and positively related to SCL responses. Bootstrapping analyses indicated that emotional non-acceptance was a significant mediator in the relationships between ELS and both cortisol and SCL responses. Emotional non-acceptance is thus one of the psychological mechanisms underlying blunted cortisol and increased sympathetic reactivity in young healthy volunteers with a history of ELS. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Construction of the Examination Stress Scale for Adolescent Students

    Science.gov (United States)

    Sung, Yao-Ting; Chao, Tzu-Yang

    2015-01-01

    The tools used for measuring examination stress have three main limitations: sample selected, sample sizes, and measurement contents. In this study, we constructed the Examination Stress Scale (ExamSS), and 4,717 high school students participated in this research. The results indicate that ExamSS has satisfactory reliability, construct validity,…

  9. The Interactive Effects of Stressful Family Life Events and Cortisol Reactivity on Adolescent Externalizing and Internalizing Behaviors

    Science.gov (United States)

    Steeger, Christine M.; Cook, Emily C.; Connell, Christian M.

    2016-01-01

    This study investigated the associations between stressful family life events and adolescent externalizing and internalizing behaviors, and the interactive effects of family life events and cortisol reactivity on problem behaviors. In a sample of 100 mothers and their adolescents (M age = 15.09; SD age = 0.98; 68% girls), adolescent cortisol reactivity was measured in response to a mother-adolescent conflict interaction task designed to elicit a stress response. Mothers reported on measures of family life events and adolescent problem behaviors. Results indicated that a heightened adolescent cortisol response moderated the relations between stressful family life events and both externalizing and internalizing behaviors. Results support context-dependent theoretical models, suggesting that for adolescents with higher cortisol reactivity (compared to those with lower cortisol reactivity), higher levels of stressful family life events were associated with greater problem behaviors, whereas lower levels of stressful family life events were related to fewer problem behaviors. PMID:26961703

  10. Reactivity to Social Stress in Subclinical Social Anxiety: Emotional Experience, Cognitive Appraisals, Behavior, and Physiology

    OpenAIRE

    Crişan, Liviu G.; Vulturar, Romana; Miclea, Mircea; Miu, Andrei C.

    2016-01-01

    Recent research indicates that subclinical social anxiety is associated with dysfunctions at multiple psychological and biological levels, in a manner that seems reminiscent of social anxiety disorder (SAD). This study aimed to describe multidimensional responses to laboratory-induced social stress in an analog sample selected for social anxiety symptoms. State anxiety, cognitive biases related to negative social evaluation, speech anxiety behaviors, and cortisol reactivity were assessed in t...

  11. The multitasking framework: the effects of increasing workload on acute psychobiological stress reactivity.

    Science.gov (United States)

    Wetherell, Mark A; Carter, Kirsty

    2014-04-01

    A variety of techniques exist for eliciting acute psychological stress in the laboratory; however, they vary in terms of their ease of use, reliability to elicit consistent responses and the extent to which they represent the stressors encountered in everyday life. There is, therefore, a need to develop simple laboratory techniques that reliably elicit psychobiological stress reactivity that are representative of the types of stressors encountered in everyday life. The multitasking framework is a performance-based, cognitively demanding stressor, representative of environments where individuals are required to attend and respond to several different stimuli simultaneously with varying levels of workload. Psychological (mood and perceived workload) and physiological (heart rate and blood pressure) stress reactivity was observed in response to a 15-min period of multitasking at different levels of workload intensity in a sample of 20 healthy participants. Multitasking stress elicited increases in heart rate and blood pressure, and increased workload intensity elicited dose-response increases in levels of perceived workload and mood. As individuals rarely attend to single tasks in real life, the multitasking framework provides an alternative technique for modelling acute stress and workload in the laboratory. Copyright © 2013 John Wiley & Sons, Ltd.

  12. Emotional stress-reactivity and positive affect among college students: the role of depression history.

    Science.gov (United States)

    O'Hara, Ross E; Armeli, Stephen; Boynton, Marcella H; Tennen, Howard

    2014-02-01

    Multiple theories posit that people with a history of depression are at higher risk for a depressive episode than people who have never experienced depression, which may be partly due to differences in stress-reactivity. In addition, both the dynamic model of affect and the broaden-and-build theory suggest that stress and positive affect interact to predict negative affect, but this moderation has never been tested in the context of depression history. The current study used multilevel modeling to examine these issues among 1,549 college students with or without a history of depression. Students completed a 30-day online diary study in which they reported daily their perceived stress, positive affect, and negative affect (including depression, anxiety, and hostility). On days characterized by higher than usual stress, students with a history of depression reported greater decreases in positive affect and greater increases in depressed affect than students with no history. Furthermore, the relations between daily stress and both depressed and anxious affect were moderated by daily positive affect among students with remitted depression. These results indicate that students with a history of depression show greater stress-reactivity even when in remission, which may place them at greater risk for recurrence. These individuals may also benefit more from positive affect on higher stress days despite being less likely to experience positive affect on such days. The current findings have various implications both clinically and for research on stress, mood, and depression. (PsycINFO Database Record (c) 2014 APA, all rights reserved). PsycINFO Database Record (c) 2014 APA, all rights reserved.

  13. An approach to an acute emotional stress reference scale.

    Science.gov (United States)

    Garzon-Rey, J M; Arza, A; de-la-Camara, C; Lobo, A; Armario, A; Aguilo, J

    2017-06-16

    The clinical diagnosis aims to identify the degree of affectation of the psycho-physical state of the patient as a guide to therapeutic intervention. In stress, the lack of a measurement tool based on a reference makes it difficult to quantitatively assess this degree of affectation. To define and perform a primary assessment of a standard reference in order to measure acute emotional stress from the markers identified as indicators of the degree. Psychometric tests and biochemical variables are, in general, the most accepted stress measurements by the scientific community. Each one of them probably responds to different and complementary processes related to the reaction to a stress stimulus. The reference that is proposed is a weighted mean of these indicators by assigning them relative weights in accordance with a principal components analysis. An experimental study was conducted on 40 healthy young people subjected to the psychosocial stress stimulus of the Trier Social Stress Test in order to perform a primary assessment and consistency check of the proposed reference. The proposed scale clearly differentiates between the induced relax and stress states. Accepting the subjectivity of the definition and the lack of a subsequent validation with new experimental data, the proposed standard differentiates between a relax state and an emotional stress state triggered by a moderate stress stimulus, as it is the Trier Social Stress Test. The scale is robust. Although the variations in the percentage composition slightly affect the score, but they do not affect the valid differentiation between states.

  14. Evidence for altered brain reactivity to norepinephrine in Veterans with a history of traumatic stress

    Directory of Open Access Journals (Sweden)

    Rebecca C. Hendrickson

    2018-02-01

    Full Text Available Background: Increases in the quantity or impact of noradrenergic signaling have been implicated in the pathophysiology of posttraumatic stress disorder (PTSD. This increased signaling may result from increased norepinephrine (NE release, from altered brain responses to NE, or from a combination of both factors. Here, we tested the hypothesis that Veterans reporting a history of trauma exposure would show an increased association between brain NE and mental health symptoms commonly observed after trauma, as compared to Veterans who did not report a history of trauma exposure, consistent with the possibility of increased brain reactivity to NE after traumatic stress. Methods: Using a convenience sample of 69 male Veterans with a history of combat-theater deployment, we examined the relationship between trauma-related mental health symptoms and the concentration of NE in cerebrospinal fluid (CSF. CSF NE levels were measured by HPLC in CSF from morning lumbar puncture. Behavioral symptoms associated with diagnoses of PTSD, depression, insomnia, or post-concussive syndrome (PCS, which together cover a wide variety of symptoms associated with alterations in arousal systems, such as sleep, mood, concentration, and anxiety, were assessed via self-report (PTSD Checklist [PCL] for PTSD, Patient Health Questionnaire 9 [PHQ9] for depression, Pittsburgh Sleep Quality Index [PSQI] for sleep problems including insomnia, and Neurobehavioral Symptom Inventory [NSI] for PCS and structured clinical interview (Clinician-Administered PSTD Scale [CAPS]. Individuals meeting criterion A of the DSM-IV diagnostic criteria for PTSD were considered trauma-exposed. Linear regression models were used to quantify the association between CSF NE and symptom intensity in participants with and without a history of trauma exposure, as well as in participants with a history of trauma exposure who were currently taking the noradrenergic receptor antagonist prazosin. Results: Fifty

  15. Scale effect in fatigue resistance under complex stressed state

    International Nuclear Information System (INIS)

    Sosnovskij, L.A.

    1979-01-01

    On the basis the of the fatigue failure statistic theory obtained is the formula for calculated estimation of probabillity of failure under complex stressed state according to partial probabilities of failure under linear stressed state with provision for the scale effect. Also the formula for calculation of equivalent stress is obtained. The verification of both formulae using literary experimental data for plane stressed state torsion has shown that the error of estimations does not exceed 10% for materials with the ultimate strength changing from 61 to 124 kg/mm 2

  16. Pain-related stress in the Neonatal Intensive Care Unit and salivary cortisol reactivity to socio-emotional stress in 3-month-old very preterm infants.

    Science.gov (United States)

    Provenzi, Livio; Giusti, Lorenzo; Fumagalli, Monica; Tasca, Hilarj; Ciceri, Francesca; Menozzi, Giorgia; Mosca, Fabio; Morandi, Francesco; Borgatti, Renato; Montirosso, Rosario

    2016-10-01

    Very preterm (VPT) infants are hospitalized in the Neonatal Intensive Care Unit (NICU) and exposed to varying levels of skin-breaking procedures (pain-related stress), even in absence of severe clinical conditions. Repeated and prolonged pain exposure may alter hypothalamic-pituitary-adrenal (HPA) axis reactivity in VPT infants. During the post-discharge period, altered HPA axis reactivity has been documented in response to non-social stressors, using salivary cortisol as a biomarker. However, little is known about the effects of NICU pain-related stress on subsequent HPA axis reactivity to socio-emotional stress in infants. We examined the relationship between pain-related stress in NICU and HPA axis reactivity (i.e., salivary cortisol reactivity) to an age-appropriate socio-emotional condition in 37 healthy VPT infants compared to 53 full-term (FT) controls. The number of skin-breaking procedures was obtained across NICU stay for VPT infants. At 3 months (corrected age for prematurity), all infants participated in the maternal Face-to-Face Still-Face (FFSF) procedure, in order to assess HPA axis reactivity to socio-emotional stress (i.e., maternal unresponsiveness). VPT infants exhibited a blunted salivary cortisol reactivity, which was associated with the amount of skin-breaking procedures during NICU: greater pain-related stress predicted lower salivary cortisol reactivity, adjusting for neonatal confounders. These findings further advance our knowledge of how early exposure to pain-related stress in NICU contributes to the programming of an altered HPA axis reactivity to socio-emotional stress in 3-month-old VPT infants, even in the absence of major perinatal complications. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Childhood trauma, psychosis liability and social stress reactivity: a virtual reality study.

    Science.gov (United States)

    Veling, W; Counotte, J; Pot-Kolder, R; van Os, J; van der Gaag, M

    2016-12-01

    Childhood trauma is associated with higher risk for mental disorders, including psychosis. Heightened sensitivity to social stress may be a mechanism. This virtual reality study tested the effect of childhood trauma on level of paranoid ideations and distress in response to social stress, in interaction with psychosis liability and level of social stress exposure. Seventy-five individuals with higher psychosis liability (55 with recent onset psychotic disorder and 20 at ultra-high risk for psychosis) and 95 individuals with lower psychosis liability (42 siblings and 53 controls) were exposed to a virtual café in five experiments with 0-3 social stressors (crowded, other ethnicity and hostility). Paranoid ideation was measured after each experiment. Subjective distress was self-rated before and after experiments. Multilevel random regression analyses were used to test main effects of childhood trauma and interaction effects. Childhood trauma was more prevalent in individuals with higher psychosis liability, and was associated with higher level of (subclinical) psychotic and affective symptoms. Individuals with a history of childhood trauma responded with more subjective distress to virtual social stress exposures. The effects of childhood trauma on paranoia and subjective distress were significantly stronger when the number of virtual environmental stressors increased. Higher psychosis liability increased the effect of childhood trauma on peak subjective distress and stress reactivity during experiments. Childhood trauma is associated with heightened social stress sensitivity and may contribute to psychotic and affective dysregulation later in life, through a sensitized paranoid and stress response to social stressors.

  18. Effects of prenatal stress and emotional reactivity of the mother on emotional and cognitive abilities in lambs.

    Science.gov (United States)

    Coulon, Marjorie; Nowak, Raymond; Andanson, Stephane; Petit, Bérengère; Lévy, Frédéric; Boissy, Alain

    2015-07-01

    Consequences of prenatal stress on emotional reactivity and cognitive abilities in offspring are under-documented in precocial mammals. Here, we investigated to what extent emotional reactivity, judgment bias and spatial learning abilities of lambs are affected by chronic stress during late pregnancy and by their dams' emotional reactivity. The 20 highest-responsive (HR) and 20 lowest-responsive (LR) ewes from a population of 120 Romane ewes were selected according to their pre-mating reactivity to social isolation in a new environment. Over the final third of pregnancy, 10 HR ewes and 10 LR ewes were exposed daily to various unpredictable aversive events such as restraint, mixing groups and transport while the other 20 selected ewes were not. In a human and an object test, prenatally-stressed lambs were more fearful than control lambs, but the prenatal stress effect was moderated by the reactivity of the mothers: prenatally-stressed lambs from ewes with high emotional reactivity were more affected. Prenatally-stressed lambs did not perform as well as control lambs in a maze test and showed pessimistic-like judgment in a cognitive bias test. Prenatally-stressed lambs were thus characterized by a negative affective state with increased fear reactions and impaired cognitive evaluation. The development of negative moods could have long-lasting consequences on the coping strategies of the lambs in response to their rearing conditions. © 2015 Wiley Periodicals, Inc.

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

    Directory of Open Access Journals (Sweden)

    Haroon I. Sheikh

    2014-01-01

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

  20. Differential Autonomic Nervous System Reactivity in Depression and Anxiety During Stress Depending on Type of Stressor.

    Science.gov (United States)

    Hu, Mandy X; Lamers, Femke; de Geus, Eco J C; Penninx, Brenda W J H

    2016-06-01

    It remains unclear whether depressive and anxiety disorders are associated with hyporeactivity or hyperreactivity of the autonomic nervous system (ANS) and whether deviant reactivity occurs in all types of stressors. This study compared ANS reactivity in people with current or remitted depression/anxiety with reactivity in healthy controls during two stress conditions. From the Netherlands Study of Depression and Anxiety, data of 804 individuals with current depression/anxiety, 913 individuals with remitted depression/anxiety, and 466 healthy controls (mean age = 44.1 years; 66.4% female) were available. Two conditions were used to evoke stress: a) an n-back task, a cognitively challenging stressor, and 2) a psychiatric interview, evoking personal-emotional stress related to the occurrence of symptoms of depression/anxiety. Indicators of ANS activity were heart rate (HR), root mean square of differences between successive interbeat intervals (RMSSD), respiratory sinus arrhythmia (RSA), and preejection period. As compared with controls, participants with psychopathology had significant hyporeactivity of HR (controls = 4.1 ± 4.2 beats/min; remitted = 3.5 ± 3.5 beats/min; current psychopathology = 3.1 ± 3.4 beats/min), RMSSD (controls = -6.2 ± 14.5 milliseconds; remitted = -5.4 ± 17.8 milliseconds; current psychopathology = -3.5 ± 15.4 milliseconds), and RSA (controls = -9.3 ± 17.0 milliseconds; remitted = -7.4 ± 16.5 milliseconds; current psychopathology = -6.9 ± 15.0 milliseconds) during the n-back task. In contrast, during the psychiatric interview, they showed significant hyperreactivity of HR (controls = 2.7 ± 3.4 beats/min; remitted = 3.5 ± 3.4 beats/min; current psychopathology = 4.0 ± 3.3 beats/min), RMSSD (controls = -3.4 ± 12.2 milliseconds; remitted = -4.1 ± 12.1 milliseconds; current psychopathology = -5.6 ± 11.8 milliseconds), and RSA (controls = -3.8 ± 8.1 milliseconds; remitted = -4.3 ± 7.9 milliseconds; current psychopathology = -5.0

  1. Mice selected for high versus low stress reactivity: a new animal model for affective disorders.

    Science.gov (United States)

    Touma, Chadi; Bunck, Mirjam; Glasl, Lisa; Nussbaumer, Markus; Palme, Rupert; Stein, Hendrik; Wolferstätter, Michael; Zeh, Ramona; Zimbelmann, Marina; Holsboer, Florian; Landgraf, Rainer

    2008-07-01

    Affective disorders such as major depression are among the most prevalent and costly diseases of the central nervous system, but the underlying mechanisms are still poorly understood. In recent years, it has become evident that alterations of the stress hormone system, in particular dysfunctions (hyper- or hypo-activity) of the hypothalamic-pituitary-adrenal (HPA) axis, play a prominent role in the development of major depressive disorders. Therefore, we aimed to generate a new animal model comprising these neuroendocrine core symptoms in order to unravel parameters underlying increased or decreased stress reactivity. Starting from a population of outbred mice (parental generation: 100 males and 100 females of the CD-1 strain), two breeding lines were established according to the outcome of a 'stress reactivity test' (SRT), consisting of a 15-min restraint period and tail blood samplings immediately before and after exposure to the stressor. Mice showing a very high or a very low secretion of corticosterone in the SRT, i.e. animals expressing a hyper- or a hypo-reactivity of the HPA axis, were selected for the 'high reactivity' (HR) and the 'low reactivity' (LR) breeding line, respectively. Additionally, a third breeding line was established consisting of animals with an 'intermediate reactivity' (IR) in the SRT. Already in the first generation, i.e. animals derived from breeding pairs selected from the parental generation, significant differences in the reactivity of the HPA axis between HR, IR, and LR mice were observed. Moreover, these differences were found across all subsequent generations and could be increased by selective breeding, which indicates a genetic basis of the respective phenotype. Repeated testing of individuals in the SRT furthermore proved that the observed differences in stress responsiveness are present already early in life and can be regarded as a robust genetic predisposition. Tests investigating the animal's emotionality including anxiety

  2. Growing Up Or Growing Old? Cellular Aging Linked With Testosterone Reactivity To Stress In Youth

    Science.gov (United States)

    Drury, Stacy S.; Shirtcliff, Elizabeth A.; Shachet, Andrew; Phan, Jenny; Mabile, Emily; Brett, Zoë H.; Wren, Michael; Esteves, Kyle; Theall, Katherine P.

    2014-01-01

    Background Given the established relation between testosterone and aging in older adults, we tested whether buccal telomere length (TL), an established cellular biomarker of aging, was associated with testosterone levels in youth. Methods Children, mean age 10.2 years, were recruited from the greater New Orleans area and salivary testosterone was measured during both an acute stressor and diurnally. Buccal TL was measured using monochrome multiplex quantitative real-time PCR (MMQ-PCR). Testosterone and telomere length data was available on 77 individuals. The association between buccal TL and testosterone was tested using multivariate Generalized Estimating Equations (GEE) to account for clustering of children within families. Results Greater peak testosterone levels (β=-0.87, p < 0.01) and slower recovery (β=-0.56, p < 0.01) and reactivity (β = -1.22, p < 0.01) following a social stressor were significantly associated with shorter buccal TL after controlling for parental age at conception, child age, sex, sociodemographic factors and puberty. No association was initially present between diurnal measurements of testosterone or morning basal testosterone levels and buccal TL. Sex significantly moderated the relation between testosterone reactivity and buccal TL. Conclusions The association between testosterone and buccal TL supports gonadal maturation as a developmentally sensitive biomarker of aging within youth. As stress levels of testosterone were significantly associated with buccal TL, these findings are consistent with the growing literature linking stress exposure and accelerated maturation. The lack of association of diurnal testosterone or morning basal levels with buccal TL bolsters the notion of a shared stress-related maturational mechanism between cellular stress and the hypothalamic pituitary gonadal (HPG) axis. These data provide novel evidence supporting the interaction of aging, physiologic stress and cellular processes as an underlying

  3. A Preliminary Experimental Examination of Worldview Verification, Perceived Racism, and Stress Reactivity in African Americans

    Science.gov (United States)

    Lucas, Todd; Lumley, Mark A.; Flack, John M.; Wegner, Rhiana; Pierce, Jennifer; Goetz, Stefan

    2016-01-01

    Objective According to worldview verification theory, inconsistencies between lived experiences and worldviews are psychologically threatening. These inconsistencies may be key determinants of stress processes that influence cardiovascular health disparities. This preliminary examination considers how experiencing injustice can affect perceived racism and biological stress reactivity among African Americans. Guided by worldview verification theory, it was hypothesized that responses to receiving an unfair outcome would be moderated by fairness of the accompanying decision process, and that this effect would further depend on the consistency of the decision process with preexisting justice beliefs. Method A sample of 118 healthy African American adults completed baseline measures of justice beliefs, followed by a laboratory-based social-evaluative stressor task. Two randomized fairness manipulations were implemented during the task: participants were given either high or low levels of distributive (outcome) and procedural (decision process) justice. Glucocorticoid (cortisol) and inflammatory (C-reactive protein) biological responses were measured in oral fluids, and attributions of racism were also measured. Results The hypothesized 3-way interaction was generally obtained. Among African Americans with a strong belief in justice, perceived racism, cortisol and C-reactive protein responses to low distributive justice were higher when procedural justice was low. Among African Americans with a weak belief in justice however, these responses were higher when a low level of distributive justice was coupled with high procedural justice. Conclusions Biological and psychological processes that contribute to cardiovascular health disparities are affected by consistency between individual-level and contextual justice factors. PMID:27018728

  4. Reactivity to Social Stress in Subclinical Social Anxiety: Emotional Experience, Cognitive Appraisals, Behavior, and Physiology

    Science.gov (United States)

    Crişan, Liviu G.; Vulturar, Romana; Miclea, Mircea; Miu, Andrei C.

    2016-01-01

    Recent research indicates that subclinical social anxiety is associated with dysfunctions at multiple psychological and biological levels, in a manner that seems reminiscent of social anxiety disorder (SAD). This study aimed to describe multidimensional responses to laboratory-induced social stress in an analog sample selected for social anxiety symptoms. State anxiety, cognitive biases related to negative social evaluation, speech anxiety behaviors, and cortisol reactivity were assessed in the Trier Social Stress Test (TSST). Results showed that social anxiety symptoms were associated with increased state anxiety, biased appraisals related to the probability and cost of negative social evaluations, behavioral changes in facial expression that were consistent with speech anxiety, and lower cortisol reactivity. In addition, multiple interrelations between responses in the TSST were found, with positive associations between subjective experience, cognitive appraisals, and observable behavior, as well as negative associations between each of the former two types of response and cortisol reactivity. These results show that in response to social stressors, subclinical social anxiety is associated with significant changes in emotional experience, cognitive appraisals, behaviors, and physiology that could parallel those previously found in SAD samples. PMID:26858658

  5. A laboratory-scale pretreatment and hydrolysis assay for determination of reactivity in cellulosic biomass feedstocks.

    Science.gov (United States)

    Wolfrum, Edward J; Ness, Ryan M; Nagle, Nicholas J; Peterson, Darren J; Scarlata, Christopher J

    2013-11-14

    The rapid determination of the release of structural sugars from biomass feedstocks is an important enabling technology for the development of cellulosic biofuels. An assay that is used to determine sugar release for large numbers of samples must be robust, rapid, and easy to perform, and must use modest amounts of the samples to be tested.In this work we present a laboratory-scale combined pretreatment and saccharification assay that can be used as a biomass feedstock screening tool. The assay uses a commercially available automated solvent extraction system for pretreatment followed by a small-scale enzymatic hydrolysis step. The assay allows multiple samples to be screened simultaneously, and uses only ~3 g of biomass per sample. If the composition of the biomass sample is known, the results of the assay can be expressed as reactivity (fraction of structural carbohydrate present in the biomass sample released as monomeric sugars). We first present pretreatment and enzymatic hydrolysis experiments on a set of representative biomass feedstock samples (corn stover, poplar, sorghum, switchgrass) in order to put the assay in context, and then show the results of the assay applied to approximately 150 different feedstock samples covering 5 different materials. From the compositional analysis data we identify a positive correlation between lignin and structural carbohydrates, and from the reactivity data we identify a negative correlation between both carbohydrate and lignin content and total reactivity. The negative correlation between lignin content and total reactivity suggests that lignin may interfere with sugar release, or that more mature samples (with higher structural sugars) may have more recalcitrant lignin. The assay presented in this work provides a robust and straightforward method to measure the sugar release after pretreatment and saccharification that can be used as a biomass feedstock screening tool. We demonstrated the utility of the assay by

  6. Effect of doxazosin on stress reactivity and the ability to resist smoking.

    Science.gov (United States)

    Verplaetse, Terril L; Weinberger, Andrea H; Oberleitner, Lindsay M; Smith, Kathryn Mz; Pittman, Brian P; Shi, Julia M; Tetrault, Jeanette M; Lavery, Meaghan E; Picciotto, Marina R; McKee, Sherry A

    2017-07-01

    Preclinical findings support a role for α1-adrenergic antagonists in reducing nicotine-motivated behaviors, but these findings have yet to be translated to humans. The current study evaluated whether doxazosin would attenuate stress-precipitated smoking in the human laboratory. Using a well-validated laboratory analogue of smoking-lapse behavior, this pilot study evaluated whether doxazosin (4 and 8 mg/day) versus placebo attenuated the effect of stress (vs neutral imagery) on tobacco craving, the ability to resist smoking and subsequent ad-libitum smoking in nicotine-deprived smokers ( n=35). Cortisol, adrenocorticotropin, norepinephrine, epinephrine, and physiologic reactivity were assessed. Doxazosin (4 and 8 mg/day vs placebo) decreased cigarettes per day during the 21-day titration period. Following titration, doxazosin (4 and 8 mg/day vs placebo) decreased tobacco craving. During the laboratory session, doxazosin (8 mg/day vs placebo) further decreased tobacco craving following stress versus neutral imagery. Doxazosin increased the latency to start smoking following stress, and reduced the number of cigarettes smoked. Dosage of 8 mg/day doxazosin increased or normalized cortisol levels following stress imagery and decreased cortisol levels following neutral imagery. These preliminary findings support a role for the noradrenergic system in stress-precipitated smoking behavior, and support further development of doxazosin as a novel pharmacotherapeutic treatment strategy for smoking cessation.

  7. Cardiac reactivity and preserved performance under stress: two sides of the same coin?

    Science.gov (United States)

    Pattyn, Nathalie; Mairesse, Olivier; Cortoos, Aisha; Morais, José; Soetens, Eric; Roelands, Bart; van den Nest, Annick; Kolinsky, Régine

    2014-07-01

    In the present experiment, cognitive control under stress was investigated using a real-life paradigm, namely an evaluation flight for military student pilots. The magnitude of cognitive interference on color-word, numerical and emotional Stroop paradigms was studied during a baseline recording and right before the test flight. Cardio-respiratory parameters were simultaneously assessed during rest and the performance of the Stroop tasks. Cognitive data suggested a different speed/accuracy trade-off under stress, and no modulation of the interference effect for color words or numerical stimuli. However, we observed a major increase in error rates for specific emotional stimuli related to the evaluation situation in the stress condition. The increase in cognitive interference from emotional stimuli, expressed as an increase in error rates, was correlated to the decreased cardiac reactivity to challenge in the stress situation. This relationship is discussed in the framework of Sanders' (1983) model of stress and performance. In terms of future research, this link warrants a fruitful lead to be followed for investigating the causal mechanism of performance decrements under the influence of stress. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Development of the Abbreviated Masculine Gender Role Stress Scale.

    Science.gov (United States)

    Swartout, Kevin M; Parrott, Dominic J; Cohn, Amy M; Hagman, Brett T; Gallagher, Kathryn E

    2015-06-01

    Data gathered from 6 independent samples (n = 1,729) that assessed men's masculine gender role stress in college and community males were aggregated used to determine the reliability and validity of an abbreviated version of the Masculine Gender Role Stress (MGRS) Scale. The 15 items with the highest item-to-total scale correlations were used to create an abbreviated MGRS Scale. Psychometric properties of each of the 15 items were examined with item response theory (IRT) analysis, using the discrimination and threshold parameters. IRT results showed that the abbreviated scale may hold promise at capturing the same amount of information as the full 40-item scale. Relative to the 40-item scale, the total score of the abbreviated MGRS Scale demonstrated comparable convergent validity using the measurement domains of masculine identity, hypermasculinity, trait anger, anger expression, and alcohol involvement. An abbreviated MGRS Scale may be recommended for use in clinical practice and research settings to reduce cost, time, and patient/participant burden. Additionally, IRT analyses identified items with higher discrimination and threshold parameters that may be used to screen for problematic gender role stress in men who may be seen in routine clinical or medical practice. (c) 2015 APA, all rights reserved).

  9. Ghrelin-reactive immunoglobulins and anxiety, depression and stress-induced cortisol response in adolescents. The TRAILS study.

    Science.gov (United States)

    François, Marie; Schaefer, Johanna M; Bole-Feysot, Christine; Déchelotte, Pierre; Verhulst, Frank C; Fetissov, Sergueï O

    2015-06-03

    Ghrelin, a hunger hormone, has been implicated in the regulation of stress-response, anxiety and depression. Ghrelin-reactive immunoglobulins (Ig) were recently identified in healthy and obese humans showing abilities to increase ghrelin's stability and orexigenic effects. Here we studied if ghrelin-reactive Ig are associated with anxiety and depression and with the stress-induced cortisol response in a general population of adolescents. Furthermore, to test the possible infectious origin of ghrelin-reactive Ig, their levels were compared with serum IgG against common viruses. We measured ghrelin-reactive IgM, IgG and IgA in serum samples of 1199 adolescents from the Dutch TRAILS study and tested their associations with 1) anxiety and depression symptoms assessed with the Youth Self-Report, 2) stress-induced salivary cortisol levels and 3) IgG against human herpesvirus 1, 2, 4 and 6 and Influenza A and B viruses. Ghrelin-reactive IgM and IgG correlated positively with levels of antibodies against Influenza A virus. Ghrelin-reactive IgM correlated negatively with antibodies against Influenza B virus. Ghrelin-reactive IgM correlated positively with anxiety scores in girls and ghrelin-reactive IgG correlated with stress-induced cortisol secretion, but these associations were weak and not significant after correction for multiple testing. These data indicate that production of ghrelin-reactive autoantibodies could be influenced by viral infections. Serum levels of ghrelin-reactive autoantibodies probably do not play a role in regulating anxiety, depression and the stress-response in adolescents from the general population. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Scaling of Anomalous Hall Effects in Facing-Target Reactively Sputtered Fe4N Films

    KAUST Repository

    Zhang, Yan

    2015-05-13

    Anomalous Hall effect (AHE) in the reactively sputtered epitaxial and polycrystalline γ′-Fe4N films is investigated systematically. The Hall resistivity is positive in the entire temperature range. The magnetization, carrier density and grain boundaries scattering have a major impact on the AHE scaling law. The scaling exponent γ in the conventional scaling of is larger than 2 in both the epitaxial and polycrystalline γ′-Fe4N films. Although γ>2 has been found in heterogeneous systems due to the effects of the surface and interface scattering on AHE, γ>2 is not expected in homogenous epitaxial systems. We demonstrated that γ>2 results from residual resistivity (ρxx0) in γ′-Fe4N films. Furthermore, the side-jump and intrinsic mechanisms are dominant in both epitaxial and polycrystalline samples according to the proper scaling relation.

  11. Perceived Stress Scale: Reliability and Validity Study in Greece

    Directory of Open Access Journals (Sweden)

    Eleni Andreou

    2011-08-01

    Full Text Available Objective: To translate the Perceived Stress Scale (versions PSS-4, -10 and -14 and to assess its psychometric properties in a sample of general Greek population. Methods: 941 individuals completed anonymously questionnaires comprising of PSS, the Depression Anxiety and Stress scale (DASS-21 version, and a list of stress-related symptoms. Psychometric properties of PSS were investigated by confirmatory factor analysis (construct validity, Cronbach’s alpha (reliability, and by investigating relations with the DASS-21 scores and the number of symptoms, across individuals’ characteristics. The two-factor structure of PSS-10 and PSS-14 was confirmed in our analysis. We found satisfactory Cronbach’s alpha values (0.82 for the full scale for PSS-14 and PSS-10 and marginal satisfactory values for PSS-4 (0.69. PSS score exhibited high correlation coefficients with DASS-21 subscales scores, meaning stress (r = 0.64, depression (r = 0.61, and anxiety (r = 0.54. Women reported significantly more stress compared to men and divorced or widows compared to married or singled only. A strong significant (p < 0.001 positive correlation between the stress score and the number of self-reported symptoms was also noted. Conclusions: The Greek versions of the PSS-14 and PSS-10 exhibited satisfactory psychometric properties and their use for research and health care practice is warranted.

  12. Perceived Stress Scale: reliability and validity study in Greece.

    Science.gov (United States)

    Andreou, Eleni; Alexopoulos, Evangelos C; Lionis, Christos; Varvogli, Liza; Gnardellis, Charalambos; Chrousos, George P; Darviri, Christina

    2011-08-01

    To translate the Perceived Stress Scale (versions PSS-4, -10 and -14) and to assess its psychometric properties in a sample of general Greek population. 941 individuals completed anonymously questionnaires comprising of PSS, the Depression Anxiety and Stress scale (DASS-21 version), and a list of stress-related symptoms. Psychometric properties of PSS were investigated by confirmatory factor analysis (construct validity), Cronbach's alpha (reliability), and by investigating relations with the DASS-21 scores and the number of symptoms, across individuals' characteristics. The two-factor structure of PSS-10 and PSS-14 was confirmed in our analysis. We found satisfactory Cronbach's alpha values (0.82 for the full scale) for PSS-14 and PSS-10 and marginal satisfactory values for PSS-4 (0.69). PSS score exhibited high correlation coefficients with DASS-21 subscales scores, meaning stress (r = 0.64), depression (r = 0.61), and anxiety (r = 0.54). Women reported significantly more stress compared to men and divorced or widows compared to married or singled only. A strong significant (p < 0.001) positive correlation between the stress score and the number of self-reported symptoms was also noted. The Greek versions of the PSS-14 and PSS-10 exhibited satisfactory psychometric properties and their use for research and health care practice is warranted.

  13. Cortisol Reactivity to Stress and Its Association With White Matter Integrity in Adults With Schizophrenia.

    Science.gov (United States)

    Nugent, Katie L; Chiappelli, Joshua; Sampath, Hemalatha; Rowland, Laura M; Thangavelu, Kavita; Davis, Beshaun; Du, Xiaoming; Muellerklein, Florian; Daughters, Stacey; Kochunov, Peter; Hong, L Elliot

    2015-09-01

    Although acute hypothalamic-pituitary-adrenal axis response to stress is often adaptive, prolonged responses may have detrimental effects. Many components of white matter structures are sensitive to prolonged cortisol exposure. We aimed to identify a behavioral laboratory assay for cortisol response related to brain pathophysiology in schizophrenia. We hypothesized that an abnormally prolonged cortisol response to stress may be linked to abnormal white matter integrity in patients with schizophrenia. Acute and prolonged salivary cortisol response was measured outside the scanner at pretest and then at 0, 20, and 40 minutes after a psychological stress task in patients with schizophrenia (n = 45) and controls (n = 53). Tract-averaged white matter was measured by 64-direction diffusion tensor imaging in a subset of patients (n = 30) and controls (n = 33). Patients who did not tolerate the psychological stress task and quit had greater acute (t = 2.52 [p = .016] and t = 3.51 [p = .001] at 0 and 20 minutes) and prolonged (t = 3.62 [p = .001] at 40 minutes) cortisol reactivity compared with patients who finished the task. Abnormally prolonged cortisol reactivity in patients was significantly associated with reduced white matter integrity (r = -0.468, p = .009). Regardless of task completion status, acute cortisol response was not related to the white matter measures in patients or controls. This paradigm was successful at identifying a subset of patients whose cortisol response was associated with brain pathophysiology. Abnormal cortisol response may adversely affect white matter integrity, partly explaining this pathology observed in schizophrenia. Prolonged stress responses may be targeted for intervention to test for protective effects against white matter damages.

  14. Alcohol consumption as a predictor of reactivity to smoking and stress cues presented in the natural environment of smokers.

    Science.gov (United States)

    Tomko, Rachel L; Saladin, Michael E; McClure, Erin A; Squeglia, Lindsay M; Carpenter, Matthew J; Tiffany, Stephen T; Baker, Nathaniel L; Gray, Kevin M

    2017-02-01

    The high prevalence of co-occurring alcohol and tobacco use underscores the importance of understanding the influence of alcohol consumption on risk factors for smoking and relapse. Alcohol has been shown to impact reactivity to smoking and stress-related cues, both of which are common antecedents to smoking and smoking relapse. The objective of the current study is to examine associations between alcohol use, cigarette craving, and stress reactivity following exposure to smoking and stress cues delivered in participants' daily lives. Using cue-reactivity ecological momentary assessment (CREMA), adult smokers (n = 138) reported cigarette craving, stress, and past hour alcohol use on a mobile device four times per day for 2 weeks, resulting in a range of 4493-5983 data points per analysis. Questions were followed by exposure to pictorial neutral, stressful, or smoking cues delivered via the mobile device. Craving and affect were re-assessed following cue exposure. Results showed that recent (past hour) alcohol use was significantly associated with increases in the following: (a) tonic (non-cue-elicited) cigarette craving, (b) stress cue-elicited cigarette craving, and (c) stress cue-elicited stress reactivity, in the context of high-baseline stress. There was no significant association between alcohol use and smoking cue-elicited craving. Alcohol use may increase risk for smoking and relapse to smoking by increasing cigarette craving and, in certain contexts, stress following stress cue exposure. Though alcohol is known for its anxiolytic properties, under some conditions, it may increase reactivity to stress cues.

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

    Science.gov (United States)

    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.

  16. Amygdala Reactivity and Anterior Cingulate Habituation Predict Posttraumatic Stress Disorder Symptom Maintenance After Acute Civilian Trauma.

    Science.gov (United States)

    Stevens, Jennifer S; Kim, Ye Ji; Galatzer-Levy, Isaac R; Reddy, Renuka; Ely, Timothy D; Nemeroff, Charles B; Hudak, Lauren A; Jovanovic, Tanja; Rothbaum, Barbara O; Ressler, Kerry J

    2017-06-15

    Studies suggest that exaggerated amygdala reactivity is a vulnerability factor for posttraumatic stress disorder (PTSD); however, our understanding is limited by a paucity of prospective, longitudinal studies. Recent studies in healthy samples indicate that, relative to reactivity, habituation is a more reliable biomarker of individual differences in amygdala function. We investigated reactivity of the amygdala and cortical areas to repeated threat presentations in a prospective study of PTSD. Participants were recruited from the emergency department of a large level I trauma center within 24 hours of trauma. PTSD symptoms were assessed at baseline and approximately 1, 3, 6, and 12 months after trauma. Growth curve modeling was used to estimate symptom recovery trajectories. Thirty-one individuals participated in functional magnetic resonance imaging around the 1-month assessment, passively viewing fearful and neutral face stimuli. Reactivity (fearful > neutral) and habituation to fearful faces was examined. Amygdala reactivity, but not habituation, 5 to 12 weeks after trauma was positively associated with the PTSD symptom intercept and predicted symptoms at 12 months after trauma. Habituation in the ventral anterior cingulate cortex was positively associated with the slope of PTSD symptoms, such that decreases in ventral anterior cingulate cortex activation over repeated presentations of fearful stimuli predicted increasing symptoms. Findings point to neural signatures of risk for maintaining PTSD symptoms after trauma exposure. Specifically, chronic symptoms were predicted by amygdala hyperreactivity, and poor recovery was predicted by a failure to maintain ventral anterior cingulate cortex activation in response to fearful stimuli. The importance of identifying patients at risk after trauma exposure is discussed. Copyright © 2017 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  17. Childhood poverty and stress reactivity are associated with aberrant functional connectivity in default mode network.

    Science.gov (United States)

    Sripada, Rebecca K; Swain, James E; Evans, Gary W; Welsh, Robert C; Liberzon, Israel

    2014-08-01

    Convergent research suggests that childhood poverty is associated with perturbation in the stress response system. This might extend to aberrations in the connectivity of large-scale brain networks, which subserve key cognitive and emotional functions. Resting-state brain activity was measured in adults with a documented history of childhood poverty (n=26) and matched controls from middle-income families (n=26). Participants also underwent a standard laboratory social stress test and provided saliva samples for cortisol assay. Childhood poverty was associated with reduced default mode network (DMN) connectivity. This, in turn, was associated with higher cortisol levels in anticipation of social stress. These results suggest a possible brain basis for exaggerated stress sensitivity in low-income individuals. Alterations in DMN may be associated with less efficient cognitive processing or greater risk for development of stress-related psychopathology among individuals who experienced the adversity of chronic childhood poverty.

  18. The Influence of Perceived Stress on Cortical Reactivity: A Proof-Of-Principle Study.

    Directory of Open Access Journals (Sweden)

    Rosan Luijcks

    Full Text Available The aim of this study was to investigate how perceived stress may affect electroencephalographical (EEG activity in a stress paradigm in a sample of 76 healthy participants. EEG activity was analyzed using multilevel modeling, allowing estimation of nested effects (EEG time segments within subjects. The stress paradigm consisted of a 3-minute pre-stimulus stress period and a 2-minute post-stimulus phase. At t=3 minutes, a single electrical stimulus was delivered. Participants were unaware of the precise moment of stimulus delivery and its intensity level. In the EEG time course of alpha activity, a stronger increase was observed during the post-stimulus period as compared to the pre-stimulus period. An opposite time course effect was apparent for gamma activity. Both effects were in line with a priori expectations and support the validity of this experimental EEG-stress paradigm. Secondly, we investigated whether interaction effects of stress and coping, as measured with the Perceived Stress Scale-10 questionnaire (PSS-10, could be demonstrated. A higher perceived stress score was accompanied by a greater increase in delta- and theta-activity during the post-stimulus phase, compared to low scores. In contrast, low coping capacity was associated with a stronger decrease in slow beta, fast beta and gamma activity during the post-stimulus phase. The results of the present article may be interpreted as proof-of-principle that EEG stress-related activity depends on the level of subjectively reported perceived stress. The inclusion of psychosocial variables measuring coping styles as well as stress-related personality aspects permits further examination of the interconnection between mind and body and may inform on the process of transformation from acute to chronic stress.

  19. Association Between Stress-Related Sleep Reactivity and Metacognitive Beliefs About Sleep in Insomnia Disorder: Preliminary Results.

    Science.gov (United States)

    Palagini, Laura; Bruno, Rosa Maria; Paolo, Toti; Caccavale, Lisa; Gronchi, Alessia; Mauri, Mauro; Riemann, Dieter; Drake, Christopher L

    2016-01-01

    To evaluate the relation between stress-related sleep reactivity and metacognitive beliefs about sleep in subjects with insomnia disorder (93) and in a group of healthy controls (30) a set of variables, including Ford Insomnia Response to Stress Test (FIRST) and Metacognition Questionnaire-Insomnia (MCQ-I), have been used. Internal consistency of the Italian version of FIRST was studied. Univariate correlation, regression analysis, and principal component analysis were also performed. The Italian version of FIRST showed good internal consistency and discriminant validity. Sleep reactivity was higher in women (p sleep (p sleep reactivity. Therapeutic strategies acting selectively on metacognition to reduce stress-related sleep reactivity in insomnia may be useful.

  20. Post Audit of a Field Scale Reactive Transport Model of Uranium at a Former Mill Site

    Science.gov (United States)

    Curtis, G. P.

    2015-12-01

    Reactive transport of hexavalent uranium (U(VI)) in a shallow alluvial aquifer at a former uranium mill tailings site near Naturita CO has been monitored for nearly 30 years by the US Department of Energy and the US Geological Survey. Groundwater at the site has high concentrations of chloride, alkalinity and U(VI) as a owing to ore processing at the site from 1941 to 1974. We previously calibrated a multicomponent reactive transport model to data collected at the site from 1986 to 2001. A two dimensional nonreactive transport model used a uniform hydraulic conductivity which was estimated from observed chloride concentrations and tritium helium age dates. A reactive transport model for the 2km long site was developed by including an equilibrium U(VI) surface complexation model calibrated to laboratory data and calcite equilibrium. The calibrated model reproduced both nonreactive tracers as well as the observed U(VI), pH and alkalinity. Forward simulations for the period 2002-2015 conducted with the calibrated model predict significantly faster natural attenuation of U(VI) concentrations than has been observed by the persistent high U(VI) concentrations at the site. Alternative modeling approaches are being evaluating evaluated using recent data to determine if the persistence can be explained by multirate mass transfer models developed from experimental observations at the column scale(~0.2m), the laboratory tank scale (~2m), the field tracer test scale (~1-4m) or geophysical observation scale (~1-5m). Results of this comparison should provide insight into the persistence of U(VI) plumes and improved management options.

  1. Assessment of plasma C-reactive protein as a biomarker of posttraumatic stress disorder risk.

    Science.gov (United States)

    Eraly, Satish A; Nievergelt, Caroline M; Maihofer, Adam X; Barkauskas, Donald A; Biswas, Nilima; Agorastos, Agorastos; O'Connor, Daniel T; Baker, Dewleen G

    2014-04-01

    Posttraumatic stress disorder (PTSD) has been associated in cross-sectional studies with peripheral inflammation. It is not known whether this observed association is the result of PTSD predisposing to inflammation (as sometimes postulated) or to inflammation predisposing to PTSD. To determine whether plasma concentration of the inflammatory marker C-reactive protein (CRP) helps predict PTSD symptoms. The Marine Resiliency Study, a prospective study of approximately 2600 war zone-deployed Marines, evaluated PTSD symptoms and various physiological and psychological parameters before deployment and at approximately 3 and 6 months following a 7-month deployment. Participants were recruited from 4 all-male infantry battalions imminently deploying to a war zone. Participation was requested of 2978 individuals; 2610 people (87.6%) consented and 2555 (85.8%) were included in the present analysis. Postdeployment data on combat-related trauma were included for 2208 participants (86.4% of the 2555 included) and on PTSD symptoms at 3 and 6 months after deployment for 1861 (72.8%) and 1617 (63.3%) participants, respectively. Severity of PTSD symptoms 3 months after deployment assessed by the Clinician-Administered PTSD Scale (CAPS). We determined the effects of baseline plasma CRP concentration on postdeployment CAPS using zero-inflated negative binomial regression (ZINBR), a procedure designed for distributions, such as CAPS in this study, that have an excess of zeroes in addition to being positively skewed. Adjusting for the baseline CAPS score, trauma exposure, and other relevant covariates, we found baseline plasma CRP concentration to be a highly significant overall predictor of postdeployment CAPS scores (P = .002): each 10-fold increment in CRP concentration was associated with an odds ratio of nonzero outcome (presence vs absence of any PTSD symptoms) of 1.51 (95% CI, 1.15-1.97; P = .003) and a fold increase in outcome with a nonzero value (extent of symptoms

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

    Science.gov (United States)

    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…

  3. Relationship between depression anxiety stress scale (DASS) and urinary hydroxyproline and proline concentrations in hospital workers.

    Science.gov (United States)

    Lee, Keou Won; Kim, Soo Jeong; Park, Jae Beom; Lee, Kyung Jong

    2011-01-01

    Although increased reactive oxygen species (ROS) is caused by stress accelerates collagen degradation, there was no data on the relationship between stress and urinary hydroxyproline (Hyp) and proline (Pro), a good marker of collagen degradation. The purpose of this study was to evaluate the relationship between depression, anxiety, and stress (DAS) and concentrations of urinary Hyp and Pro. 97 hospital employees aged 20 to 58 were asked to fill out comprehensive self-administrated questionnaires containing information about their medical history, lifestyle, length of the work year, shift-work and DAS. depression anxiety stress scale (DASS) was applied to evaluate chronic mental disorders. Urine samples were analyzed using high performance liquid chromatography (HPLC) with double derivatization for the assay of hydroxyproline and proline. The mean value of Hyp and Pro concentration in all subjects was 194.1 ± 113.4 μmol/g and 568.2 ± 310.7 μmol/g. DASS values and urinary Pro concentrations were differentiated by sex (female > male, p others, p < 0.05). In the stepwise multiple linear regressions, urinary Hyp and Pro concentrations were influenced by stress (Adjusted r2 = 0.051) and anxiety and job (Adjusted r2 = 0.199), respectively. We found that stress and anxiety were correlated with urinary Hyp and Pro concentrations. To identifying a definite correlation, further study in large populations will be needed.

  4. Depression and anxiety: Associations with biological and perceived stress reactivity to a psychological stress protocol in a middle-aged population

    NARCIS (Netherlands)

    de Rooij, Susanne R.; Schene, Aart H.; Phillips, David I.; Roseboom, Tessa J.

    2010-01-01

    Background: Depression and anxiety have been linked to higher as well as lower reactivity to stressful circumstances. Large, population-based studies investigating the association between depression and anxiety, perceived and physiological stress responses are lacking. Methods: We studied 725 men

  5. Mediating role of stress reactivity in the effects of prenatal tobacco exposure on childhood mental health outcomes.

    Science.gov (United States)

    Park, Aesoon; O'Malley, Stephanie S; King, Sarah L; Picciotto, Marina R

    2014-02-01

    Prenatal tobacco exposure, through maternal smoking during pregnancy, has been associated with adverse mental health outcomes in childhood. However, the mechanisms by which prenatal tobacco exposure compromises mental health later in life are unclear. We hypothesized that sensitized reactivity to stressful life events in early childhood mediates the effect of prenatal tobacco exposure on mental health outcomes in middle childhood, after accounting for earlier mental health outcomes. Data were from 12,308 mothers and their children drawn from the Avon Longitudinal Study of Parents and Children, a large prospective population-based study. Mothers' self-reports of smoking during pregnancy, mothers' ratings of their child's reactivity to stressful life events, and teachers' and mothers' ratings of the Strengths and Difficulties Questionnaire assessing 5 domains of mental health outcomes were measured. A positive association was found between prenatal tobacco exposure and stress reactivity between the ages of 2 and 6. In turn, stress reactivity was positively associated with peer (isolation), hyperactivity, conduct, and emotional problems (but not prosocial behaviors) between the ages of 7 and 11, after accounting for the mental health outcome at age 4 and other confounders. Heightened stress reactivity in preschool ages mediated the effect of prenatal tobacco exposure on adverse mental health outcomes between the ages of 7 and 11. Interventions to assist children exposed to tobacco smoke during gestation in coping with stressful life events may help mitigate psychiatric symptoms in this population.

  6. Child Abuse, Resting Blood Pressure, and Blood Pressure Reactivity to Psychosocial Stress.

    Science.gov (United States)

    Gooding, Holly C; Milliren, Carly E; Austin, S Bryn; Sheridan, Margaret A; McLaughlin, Katie A

    2016-01-01

    Childhood trauma is associated with hypertension in adults. It is unknown whether childhood trauma predicts elevated blood pressure earlier in development. We investigated whether the trauma of child abuse was associated with blood pressure in adolescents. The sample included 145 adolescents aged 13-17 years, 40% with exposure to child abuse. The mean age of participants was 14.93 years (SD = 1.33); 58% were female. The majority self-identified as non-Hispanic White (43%), with the remainder identifying as non-Hispanic Black (17%), Hispanic (17%), or other/mixed race (23%). We used established age/sex/height-specific cutoffs to determine the prevalence of prehypertension and hypertension in the sample. We used two-sample t tests to examine associations of abuse with resting systolic blood pressure (SBP) and diastolic blood pressure (DBP) and blood pressure reactivity to the Trier Social Stress Test and a frustration task. We used linear regression to adjust for potential confounders including sociodemographic variables, body mass index, smoking, and psychopathology. Mean resting SBP and DBP were 114.07 mmHg and 61.35 mmHg in those with a history of abuse and 111.39 mmHg and 56.89 mmHg in those without a history of abuse. This difference was significant for DBP only. Twelve percent of participants met criteria for prehypertension or hypertension based on resting blood pressure values; this did not differ between those with and without an abuse history. Child abuse was associated with lower DBP and SBP reactivity to laboratory stress tasks and reduced DBP reactivity to frustration. These associations were robust to adjustment for potential confounders. Child abuse is associated with higher resting DBP and blunted DBP and SBP reactivity to laboratory stress in adolescence. These findings suggest a potential pathway by which child abuse leads to hypertension. © The Author 2015. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All

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

    Science.gov (United States)

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

    2014-08-01

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

  8. Ghrelin potentiates cardiac reactivity to stress by modulating sympathetic control and beta-adrenergic response.

    Science.gov (United States)

    Camargo-Silva, Gabriel; Turones, Larissa Córdova; da Cruz, Kellen Rosa; Gomes, Karina Pereira; Mendonça, Michelle Mendanha; Nunes, Allancer; de Jesus, Itamar Guedes; Colugnati, Diego Basile; Pansani, Aline Priscila; Pobbe, Roger Luis Henschel; Santos, Robson; Fontes, Marco Antônio Peliky; Guatimosim, Silvia; de Castro, Carlos Henrique; Ianzer, Danielle; Ferreira, Reginaldo Nassar; Xavier, Carlos Henrique

    2018-03-01

    Prior evidence indicates that ghrelin is involved in the integration of cardiovascular functions and behavioral responses. Ghrelin actions are mediated by the growth hormone secretagogue receptor subtype 1a (GHS-R1a), which is expressed in peripheral tissues and central areas involved in the control of cardiovascular responses to stress. In the present study, we assessed the role of ghrelin - GHS-R1a axis in the cardiovascular reactivity to acute emotional stress in rats. Ghrelin potentiated the tachycardia evoked by restraint and air jet stresses, which was reverted by GHS-R1a blockade. Evaluation of the autonomic balance revealed that the sympathetic branch modulates the ghrelin-evoked positive chronotropy. In isolated hearts, the perfusion with ghrelin potentiated the contractile responses caused by stimulation of the beta-adrenergic receptor, without altering the amplitude of the responses evoked by acetylcholine. Experiments in isolated cardiomyocytes revealed that ghrelin amplified the increases in calcium transient changes evoked by isoproterenol. Taken together, our results indicate that the Ghrelin-GHS-R1a axis potentiates the magnitude of stress-evoked tachycardia by modulating the autonomic nervous system and peripheral mechanisms, strongly relying on the activation of cardiac calcium transient and beta-adrenergic receptors. Copyright © 2018 Elsevier Inc. All rights reserved.

  9. Episode-specific drinking-to-cope motivation and next-day stress-reactivity.

    Science.gov (United States)

    Armeli, Stephen; O'Hara, Ross E; Covault, Jon; Scott, Denise M; Tennen, Howard

    2016-11-01

    Research consistently shows drinking-to-cope (DTC) motivation is uniquely associated with drinking-related problems. We furthered this line of research by examining whether DTC motivation is predictive of processes indicative of poor emotion regulation. Specifically, we tested whether nighttime levels of episode-specific DTC motivation, controlling for drinking level, were associated with intensified affective reactions to stress the following day (i.e. stress-reactivity). We used a micro-longitudinal design to test this hypothesis in two college student samples from demographically distinct institutions: a large, rural state university (N = 1421; 54% female) and an urban historically Black college/university (N = 452; 59% female). In both samples the within-person association between daily stress and negative affect on days following drinking episodes was stronger in the positive direction when previous night's drinking was characterized by relatively higher levels of DTC motivation. We also found evidence among students at the state university that average levels of DTC motivation moderated the daily stress-negative affect association. Findings are consistent with the notion that DTC motivation confers a unique vulnerability that affects processes associated with emotion regulation.

  10. Biological stress reactivity as an index of the two polarities of the experience model.

    Science.gov (United States)

    Silva, Jaime R; Vivanco-Carlevari, Anastassia; Barrientos, Mauricio; Martínez, Claudio; Salazar, Luis A; Krause, Mariane

    2017-10-01

    The two-polarities model of personality argues that experience is organized around two axes: interpersonal relatedness and self-definition. Differential emphasis on one of these poles defines adaptive and pathological experiences, generating anaclitic or introjective tendencies. The anaclitic pattern, on one hand, has been conceptually related with an exaggerated emphasis on interpersonal relatedness. On the other hand, the introjective pattern has been connected to high levels of self-criticism. The aim of this study was to investigate the psychophysiological basis for this relationship. Specifically, we hypothesized that the anaclitic individual should have a higher biological reactivity to stress (BRS), measured by the cortisol concentration in saliva, in an interpersonal stress induction protocol (Trier Social Stress Test). Contrary to what was expected, the results indicated that introjective participants presented a higher BSR than the anaclitic group. Interestingly, in contrast to their higher BSR, the introjective group reported a diminished subjective stress in relation to the average. In the anaclitic group, a tendency that goes in the opposite direction was found. Theoretical implications of these findings were discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Bridging scales of crustal stress patterns using the new World Stress Map

    Science.gov (United States)

    Heidbach, O.; Rajabi, M.; Cui, X.; Fuchs, K. W.; Mueller, B.; Reinecker, J.; Reiter, K.; Tingay, M. R. P.; Wenzel, F.; Xie, F.; Ziegler, M.; Zoback, M. D.; Zoback, M. L.

    2017-12-01

    Knowledge of the contemporary crustal stress field is a key parameter for the understanding of geodynamic processes such as global plate tectonics and the earthquake cycle. It is also an essential parameter for our sustainable and safe usage of Earth's resources, which is a major challenge for energy security in the 21st century. Since 1986, the World Stress Map (WSM) project has systematically compiled present-day stress information and provides a unique public domain global database. It is a long-term project based on an international network of partners from academia and industry. All data are public and available on the project website at world-stress-map.org. For the 30th anniversary of the project a new database has been compiled, containing double the amount of data records (n=42,870) including new data records from almost 4,000 deep boreholes. The new compilation focused on areas with previously sparse data coverage in order to resolve the stress pattern on different spatial scales. The significantly higher data density can now be used to resolve stress pattern heterogeneities on regional and local scales, as well as with depth in some regions. We present three results derived from the new WSM compilation: 1.) The global comparison between absolute plate motion and the mean of the orientation of maximum horizontal stress SHmax on a regular grid shows that there is still a correlation for the North and South America plate, but deviations from this general trend are now also clearly resolved. 2.) The variability of the crustal stress pattern changes when zooming in from plate-wide scale down to basin scale at 100 km. We show examples for Eastern Australia, Oklahoma and Central Europe. This regional and local variability of the stress pattern can be used as a proxy to identify and quantify regional and local stress sources by means of geomechanical-numerical models of the 3D stress tensor. 3.) Finally we present briefly the general concept of a multi-stage 3D

  12. Strategies for measuring flows of reactive nitrogen at the landscape scale

    DEFF Research Database (Denmark)

    Theobald, M.R.; Akkal, N.; Bienkowski, J.

    2011-01-01

    Within a rural landscape there are flows of reactive nitrogen (Nr) through and between the soil, vegetation, atmosphere and hydrological systems as well as transfer as a result of agricultural activities. Measurements of these flows and transfers have generally been limited to individual media (e.......g., hydrological flows) or the interface between two media (e.g., exchange between the soil and the atmosphere). However, the study of flows of Nr at the landscape scale requires a more integrated approach that combines measurement techniques to quantify the flows from one medium to the next. This paper discusses...

  13. A preliminary experimental examination of worldview verification, perceived racism, and stress reactivity in African Americans.

    Science.gov (United States)

    Lucas, Todd; Lumley, Mark A; Flack, John M; Wegner, Rhiana; Pierce, Jennifer; Goetz, Stefan

    2016-04-01

    According to worldview verification theory, inconsistencies between lived experiences and worldviews are psychologically threatening. These inconsistencies may be key determinants of stress processes that influence cardiovascular health disparities. This preliminary examination considers how experiencing injustice can affect perceived racism and biological stress reactivity among African Americans. Guided by worldview verification theory, it was hypothesized that responses to receiving an unfair outcome would be moderated by fairness of the accompanying decision process, and that this effect would further depend on the consistency of the decision process with preexisting justice beliefs. A sample of 118 healthy African American adults completed baseline measures of justice beliefs, followed by a laboratory-based social-evaluative stressor task. Two randomized fairness manipulations were implemented during the task: participants were given either high or low levels of distributive (outcome) and procedural (decision process) justice. Glucocorticoid (cortisol) and inflammatory (C-reactive protein) biological responses were measured in oral fluids, and attributions of racism were also measured. The hypothesized 3-way interaction was generally obtained. Among African Americans with a strong belief in justice, perceived racism, cortisol, and C-reactive protein responses to low distributive justice were higher when procedural justice was low. Among African Americans with a weak belief in justice however, these responses were higher when a low level of distributive justice was coupled with high procedural justice. Biological and psychological processes that contribute to cardiovascular health disparities are affected by consistency between individual-level and contextual justice factors. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  14. Disrupted amygdala-prefrontal connectivity during emotion regulation links stress-reactive rumination and adolescent depressive symptoms

    Directory of Open Access Journals (Sweden)

    Carina H. Fowler

    2017-10-01

    Full Text Available Rumination in response to stress (stress-reactive rumination has been linked to higher levels of depressive symptoms in adolescents. However, no work to date has examined the neural mechanisms connecting stress-reactive rumination and adolescent depressive symptoms. The present work attempted to bridge this gap through an fMRI study of 41 adolescent girls (Mage = 15.42, SD = 0.33 – a population in whom elevated levels of depressive symptoms, rumination, and social stress sensitivity are displayed. During the scan, participants completed two tasks: an emotion regulation task and a social stress task. Using psychophysiological interaction (PPI analyses, we found that positive functional connectivity between the amygdala and ventrolateral prefrontal cortex (VLPFC during the emotion regulation task mediated the association between stress-reactive rumination and depressive symptoms. These results suggest that stress-reactive rumination may interfere with the expression and development of neural connectivity patterns associated with effective emotion regulation, which may contribute, in turn, to heightened depressive symptoms.

  15. [Spanish adaptation of the Stress Manifestations Scale of the Student Stress Inventory (SSI-SM)].

    Science.gov (United States)

    Escobar Espejo, Milagros; Blanca, María J; Fernández-Baena, F Javier; Trianes Torres, María Victoria

    2011-08-01

    The aim of the present study was to translate into Spanish and to describe the psychometric properties of the Stress Manifestations Scale of the Student Stress Inventory (SSI-SM), developed by Fimian, Fastenau, Tashner and Cross to identify the main manifestations of stress in adolescents. The scale was applied to a sample of 1,002 pupils from years one and two of Secondary Education. The paper reports the factor structure, an item analysis, the internal consistency, differences by sex and academic year, external evidence of validity, and norms for scoring the scale. The results reveal a factor structure based on three first-order factors (emotional manifestations, physiological manifestations and behavioural manifestations) and one second-order factor (indicative of stress manifestations). In terms of external validity, there was a positive association with measures of perceived stress, aggressiveness, internalized/externalized symptoms, and a negative association with life satisfaction. The results show that the scale is an adequate tool for evaluating stress manifestations in adolescents.

  16. Beneficial effects of environmental enrichment on behavior, stress reactivity and synaptophysin/BDNF expression in hippocampus following early life stress.

    Science.gov (United States)

    Dandi, Εvgenia; Kalamari, Aikaterini; Touloumi, Olga; Lagoudaki, Rosa; Nousiopoulou, Evangelia; Simeonidou, Constantina; Spandou, Evangelia; Tata, Despina A

    2018-06-01

    Exposure to environmental enrichment can beneficially influence the behavior and enhance synaptic plasticity. The aim of the present study was to investigate the mediated effects of environmental enrichment on postnatal stress-associated impact with regard to behavior, stress reactivity as well as synaptic plasticity changes in the dorsal hippocampus. Wistar rat pups were submitted to a 3 h maternal separation (MS) protocol during postnatal days 1-21, while another group was left undisturbed. On postnatal day 23, a subgroup from each rearing condition (maternal separation, no-maternal separation) was housed in enriched environmental conditions until postnatal day 65 (6 weeks duration). At approximately three months of age, adult rats underwent behavioral testing to evaluate anxiety (Elevated Plus Maze), locomotion (Open Field Test), spatial learning and memory (Morris Water Maze) as well as non-spatial recognition memory (Novel Object Recognition Test). After completion of behavioral testing, blood samples were taken for evaluation of stress-induced plasma corticosterone using an enzyme-linked immunosorbent assay (ELISA), while immunofluorescence was applied to evaluate hippocampal BDNF and synaptophysin expression in dorsal hippocampus. We found that environmental enrichment protected against the effects of maternal separation as indicated by the lower anxiety levels and the reversal of spatial memory deficits compared to animals housed in standard conditions. These changes were associated with increased BDNF and synaptophysin expression in the hippocampus. Regarding the neuroendocrine response to stress, while exposure to an acute stressor potentiated corticosterone increases in maternally-separated rats, environmental enrichment of these rats prevented this effect. The current study aimed at investigating the compensatory role of enriched environment against the negative outcomes of adverse experiences early in life concurrently on emotional and cognitive

  17. Evidence of an IFN-γ by early life stress interaction in the regulation of amygdala reactivity to emotional stimuli.

    Science.gov (United States)

    Redlich, Ronny; Stacey, David; Opel, Nils; Grotegerd, Dominik; Dohm, Katharina; Kugel, Harald; Heindel, Walter; Arolt, Volker; Baune, Bernhard T; Dannlowski, Udo

    2015-12-01

    Since numerous studies have found that exposure to early life stress leads to increased peripheral inflammation and psychiatric disease, it is thought that peripheral immune activation precedes and possibly mediates the onset of stress-associated psychiatric disease. Despite early studies, IFNγ has received little attention relative to other inflammatory cytokines in the context of the pathophysiology of affective disorders. Neuroimaging endophenotypes have emerged recently as a promising means of elucidating these types of complex relationships including the modeling of the interaction between environmental factors and genetic predisposition. Here we investigate the GxE relationship between early-life stress and genetic variants of IFNγ on emotion processing. To investigate the impact of the relationship between genetic variants of IFNγ (rs1861494, rs2069718, rs2430561) and early life stress on emotion processing, a sample of healthy adults (n=409) undergoing an emotional faces paradigm in an fMRI study were genotyped and analysed. Information on early life stress was obtained via Childhood Trauma Questionnaire (CTQ). A positive association between early life stress and amygdala reactivity was found. Specifically, the main effect of genotype of rs1861494 on amygdala reactivity indicates a higher neural response in C allele carriers compared to T homozygotes, while we did not find main effects of rs2069718 and rs2430561. Importantly, interaction analyses revealed a specific interaction between IFNγ genotype (rs1861494) and early life stress affecting amygdala reactivity to emotional faces, resulting from a positive association between CTQ scores and amygdala reactivity in C allele carriers while this association was absent in T homozygotes. Our findings indicate that firstly the genetic variant of IFNγ (rs1861494) is involved with the regulation of amygdala reactivity to emotional stimuli and secondly, that this genetic variant moderates effects of early life

  18. Cold stress increases reactive oxygen species formation via TRPA1 activation in A549 cells.

    Science.gov (United States)

    Sun, Wenwu; Wang, Zhonghua; Cao, Jianping; Cui, Haiyang; Ma, Zhuang

    2016-03-01

    Reactive oxygen species (ROS) are responsible for lung damage during inhalation of cold air. However, the mechanism of the ROS production induced by cold stress in the lung is still unclear. In this work, we measured the changes of ROS and the cytosolic Ca(2+) concentration ([Ca(2+)]c) in A549 cell. We observed that cold stress (from 20 to 5 °C) exposure of A549 cell resulted in an increase of ROS and [Ca(2+)]c, which was completely attenuated by removing Ca(2+) from medium. Further experiments showed that cold-sensing transient receptor potential subfamily member 1 (TRPA1) agonist (allyl isothiocyanate, AITC) increased the production of ROS and the level of [Ca(2+)]c in A549 cell. Moreover, HC-030031, a TRPA1 selective antagonist, significantly inhibited the enhanced ROS and [Ca(2+)]c induced by AITC or cold stimulation, respectively. Taken together, these data demonstrated that TRPA1 activation played an important role in the enhanced production of ROS induced by cold stress in A549 cell.

  19. The study of mechanical properties and reactive stresses in the i-Ni-Nb shape memory alloys

    International Nuclear Information System (INIS)

    Popov, N.N.; Sysoeva, T.I.; Lar'kin, V.F.; Vedernikova, I.I.; Prokoshkin, S.D.

    2007-01-01

    One investigated into the effect of the induced deformation value, rate and temperature, of the thermal treatment procedure and of the chemical composition on the mechanical properties and the development of the reactive stresses in Ti-Ni-Nb system shape memory alloys. One showed the effect of the material composition and of the deformation temperature on the mechanical features of the investigated alloys. One determined the temperature and deformation conditions ensuring the maximum level of the reactive stresses in the alloys. One revealed the dependence of the maximum reactive stress value on the austenite mechanical features, namely, on its yield limit. One chose Ti-Ni-Nb alloy compositions applicable in the pipeline thermomechanical connections [ru

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

    Science.gov (United States)

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

    2014-01-01

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

  1. The construct validity of the Perceived Stress Scale

    DEFF Research Database (Denmark)

    Germund Nielsen, Marie; Ørnbøl, Eva; Vestergaard, Mogens

    2016-01-01

    Objective: Stress impacts the quality of life and is associated with increased risk of mental and physical disorders. The Perceived Stress Scale (PSS) is widely used for measuring psychological distress. Although the instrument was originally defined as a single construct, several studies based...... of 32,374 citizens who completed the PSS-10 as part of the Danish National Health Survey in 2010. We investigated the construct validity of the PSS-10 by CFA. We examined the scalability by investigating the fit of the data distribution in a unidimensional Rasch model and performing modification...... of response categories, persons and items. The scale dimensionality was additionally assessed by Mokken and Rasch analysis.  Results: The PSS-10 did not fit the Rasch model. Item four indicated the largest misfit, and items four and seven displayed disordered thresholds. Unidimensionality could...

  2. Multi-scale modeling of diffusion-controlled reactions in polymers: renormalisation of reactivity parameters.

    Science.gov (United States)

    Everaers, Ralf; Rosa, Angelo

    2012-01-07

    The quantitative description of polymeric systems requires hierarchical modeling schemes, which bridge the gap between the atomic scale, relevant to chemical or biomolecular reactions, and the macromolecular scale, where the longest relaxation modes occur. Here, we use the formalism for diffusion-controlled reactions in polymers developed by Wilemski, Fixman, and Doi to discuss the renormalisation of the reactivity parameters in polymer models with varying spatial resolution. In particular, we show that the adjustments are independent of chain length. As a consequence, it is possible to match reactions times between descriptions with different resolution for relatively short reference chains and to use the coarse-grained model to make quantitative predictions for longer chains. We illustrate our results by a detailed discussion of the classical problem of chain cyclization in the Rouse model, which offers the simplest example of a multi-scale descriptions, if we consider differently discretized Rouse models for the same physical system. Moreover, we are able to explore different combinations of compact and non-compact diffusion in the local and large-scale dynamics by varying the embedding dimension.

  3. Exhaustion-related changes in cardiovascular and cortisol reactivity to acute psychosocial stress

    DEFF Research Database (Denmark)

    Jönsson, Peter; Österberg, Kai; Wallergård, Mattias

    2015-01-01

    -pituitary-adrenal (HPA) axis and sympathetic nervous system (SNS) activations in both V-TSST sessions, together with habituation of cortisol and heart rate in the second session, but without any significant group differences. However, the former ED patients showed considerable variation in self-reported signs...... cortisol samples were collected. In addition, high frequency heart rate variability (HF-HRV), heart rate (HR), t-wave amplitude (TWA), and α-amylase were assessed to examine stress reactivity and habituation in the autonomic nervous system (ANS). The initial analyses showed clear hypothalamic...... of exhaustion (SMBQ). This led us to assign former ED patients with lower ratings into the low SMBQ group (LOWS) and those with higher ratings to the high SMBQ group (HIGHS). When repeating the analyses a different picture emerged; the HIGHS showed a lower cortisol response to the V-TSST than did the LOWS. Both...

  4. Friend or foe? Reactive oxygen species production, scavenging and signaling in plant response to environmental stresses.

    Science.gov (United States)

    Czarnocka, Weronika; Karpiński, Stanisław

    2018-01-10

    In the natural environment, plants are exposed to a variety of biotic and abiotic stress conditions that trigger rapid changes in the production and scavenging of reactive oxygen species (ROS). The production and scavenging of ROS is compartmentalized, which means that, depending on stimuli type, they can be generated and eliminated in different cellular compartments such as the apoplast, plasma membrane, chloroplasts, mitochondria, peroxisomes, and endoplasmic reticulum. Although the accumulation of ROS is generally harmful to cells, ROS play an important role in signaling pathways that regulate acclimatory and defense responses in plants, such as systemic acquired acclimation (SAA) and systemic acquired resistance (SAR). However, high accumulations of ROS can also trigger redox homeostasis disturbance which can lead to cell death, and in consequence, to a limitation in biomass and yield production. Different ROS have various half-lifetimes and degrees of reactivity toward molecular components such as lipids, proteins, and nucleic acids. Thus, they play different roles in intra- and extra-cellular signaling. Despite their possible damaging effect, ROS should mainly be considered as signaling molecules that regulate local and systemic acclimatory and defense responses. Over the past two decades it has been proven that ROS together with non-photochemical quenching (NPQ), hormones, Ca 2+ waves, and electrical signals are the main players in SAA and SAR, two physiological processes essential for plant survival and productivity in unfavorable conditions. Copyright © 2018. Published by Elsevier Inc.

  5. Diurnal and stress-reactive dehydroepiandrosterone levels and telomere length in youth.

    Science.gov (United States)

    Dismukes, Andrew R; Meyer, Vanessa J; Shirtcliff, Elizabeth A; Theall, Katherine P; Esteves, Kyle C; Drury, Stacy S

    2016-05-01

    The current investigation examined the association between the aging-related biomarkers dehydroepiandrosterone (DHEA) and telomere length (TL) in community-recruited African-American youth. The examination of DHEA included stress reactive, basal and diurnal sampling, in order to elucidate the underlying physiological process that may overlap with TL. One hundred and two participants completed the Trier Social Stressor Test for children (TSST-C). TL was obtained from all youth from buccal swabs on the same day as the TSST-C. Saliva samples from 83 participants were obtained over the course of two additional days to measure waking and diurnal levels of DHEA. DHEA diurnal slope was a robust predictor of TL (B=0.516, P<0.05), while other DHEA values were not significantly associated with TL. This study is one of the first studies to examine basal, diurnal and reactivity measurements of DHEA in youth. Furthermore, this is the first study, to our knowledge, to demonstrate a positive association between DHEA, a putative anti-aging hormone, and TL, an indicator of cellular aging. © 2016 The authors.

  6. Diurnal and stress-reactive dehydroepiandrosterone levels and telomere length in youth

    Directory of Open Access Journals (Sweden)

    Andrew R Dismukes

    2016-05-01

    Full Text Available The current investigation examined the association between the aging-related biomarkers dehydroepiandrosterone (DHEA and telomere length (TL in community-recruited African-American youth. The examination of DHEA included stress reactive, basal and diurnal sampling, in order to elucidate the underlying physiological process that may overlap with TL. One hundred and two participants completed the Trier Social Stressor Test for children (TSST-C. TL was obtained from all youth from buccal swabs on the same day as the TSST-C. Saliva samples from 83 participants were obtained over the course of two additional days to measure waking and diurnal levels of DHEA. DHEA diurnal slope was a robust predictor of TL (B=0.516, P<0.05, while other DHEA values were not significantly associated with TL. This study is one of the first studies to examine basal, diurnal and reactivity measurements of DHEA in youth. Furthermore, this is the first study, to our knowledge, to demonstrate a positive association between DHEA, a putative anti-aging hormone, and TL, an indicator of cellular aging.

  7. Unravelling chemical priming machinery in plants: the role of reactive oxygen-nitrogen-sulfur species in abiotic stress tolerance enhancement.

    Science.gov (United States)

    Antoniou, Chrystalla; Savvides, Andreas; Christou, Anastasis; Fotopoulos, Vasileios

    2016-10-01

    Abiotic stresses severely limit crop yield and their detrimental effects are aggravated by climate change. Chemical priming is an emerging field in crop stress management. The exogenous application of specific chemical agents before stress events results in tolerance enhancement and reduction of stress impacts on plant physiology and growth. However, the molecular mechanisms underlying the remarkable effects of chemical priming on plant physiology remain to be elucidated. Reactive oxygen, nitrogen and sulfur species (RONSS) are molecules playing a vital role in the stress acclimation of plants. When applied as priming agents, RONSS improve stress tolerance. This review summarizes the recent knowledge on the role of RONSS in cell signalling and gene regulation contributing to abiotic stress tolerance enhancement. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Oblique reactivation of lithosphere-scale lineaments controls rift physiography - the upper-crustal expression of the Sorgenfrei-Tornquist Zone, offshore southern Norway

    Science.gov (United States)

    Phillips, Thomas B.; Jackson, Christopher A.-L.; Bell, Rebecca E.; Duffy, Oliver B.

    2018-04-01

    Pre-existing structures within sub-crustal lithosphere may localise stresses during subsequent tectonic events, resulting in complex fault systems at upper-crustal levels. As these sub-crustal structures are difficult to resolve at great depths, the evolution of kinematically and perhaps geometrically linked upper-crustal fault populations can offer insights into their deformation history, including when and how they reactivate and accommodate stresses during later tectonic events. In this study, we use borehole-constrained 2-D and 3-D seismic reflection data to investigate the structural development of the Farsund Basin, offshore southern Norway. We use throw-length (T-x) analysis and fault displacement backstripping techniques to determine the geometric and kinematic evolution of N-S- and E-W-striking upper-crustal fault populations during the multiphase evolution of the Farsund Basin. N-S-striking faults were active during the Triassic, prior to a period of sinistral strike-slip activity along E-W-striking faults during the Early Jurassic, which represented a hitherto undocumented phase of activity in this area. These E-W-striking upper-crustal faults are later obliquely reactivated under a dextral stress regime during the Early Cretaceous, with new faults also propagating away from pre-existing ones, representing a switch to a predominantly dextral sense of motion. The E-W faults within the Farsund Basin are interpreted to extend through the crust to the Moho and link with the Sorgenfrei-Tornquist Zone, a lithosphere-scale lineament, identified within the sub-crustal lithosphere, that extends > 1000 km across central Europe. Based on this geometric linkage, we infer that the E-W-striking faults represent the upper-crustal component of the Sorgenfrei-Tornquist Zone and that the Sorgenfrei-Tornquist Zone represents a long-lived lithosphere-scale lineament that is periodically reactivated throughout its protracted geological history. The upper-crustal component of

  9. Residual stress and texture in Aluminum doped Zinc Oxide layers deposited by reactive radio frequency magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Azanza Ricardo, C.L., E-mail: Cristy.Azanza@ing.unitn.it [Department of Civil, Environmental and Mechanical Engineering, University of Trento, 38123 via Mesiano 77, Trento (Italy); Pastorelli, M.; D' Incau, M. [Department of Civil, Environmental and Mechanical Engineering, University of Trento, 38123 via Mesiano 77, Trento (Italy); Aswath, P. [College of Engineering, University of Texas at Arlington, TX (United States); Scardi, P. [Department of Civil, Environmental and Mechanical Engineering, University of Trento, 38123 via Mesiano 77, Trento (Italy)

    2016-04-30

    Aluminum doped Zinc Oxide thin films were deposited on standard soda-lime substrates by reactive radio frequency magnetron sputtering. Residual stress and texture were studied by X-ray diffraction, while X-ray Absorption Near Edge Spectroscopy provided information on the Al environment in the best performing thin films. The influence of deposition parameters on structural and microstructural properties is discussed. A correlation between microstructure and residual stress state with electrical and optical properties is proposed. - Highlights: • Al doped ZnO thin films were obtained by reactive radio frequency magnetron sputtering. • Correlation of stresses and texture with electrical and optical properties is shown. • Homogeneous and stress-free thin-films are the best performing ones. • XANES confirmed the doping mechanism and excluded some spurious phases.

  10. Reactive flow modeling of small scale detonation failure experiments for a baseline non-ideal explosive

    Energy Technology Data Exchange (ETDEWEB)

    Kittell, David E.; Cummock, Nick R.; Son, Steven F. [School of Mechanical Engineering, Purdue University, West Lafayette, Indiana 47907 (United States)

    2016-08-14

    Small scale characterization experiments using only 1–5 g of a baseline ammonium nitrate plus fuel oil (ANFO) explosive are discussed and simulated using an ignition and growth reactive flow model. There exists a strong need for the small scale characterization of non-ideal explosives in order to adequately survey the wide parameter space in sample composition, density, and microstructure of these materials. However, it is largely unknown in the scientific community whether any useful or meaningful result may be obtained from detonation failure, and whether a minimum sample size or level of confinement exists for the experiments. In this work, it is shown that the parameters of an ignition and growth rate law may be calibrated using the small scale data, which is obtained from a 35 GHz microwave interferometer. Calibration is feasible when the samples are heavily confined and overdriven; this conclusion is supported with detailed simulation output, including pressure and reaction contours inside the ANFO samples. The resulting shock wave velocity is most likely a combined chemical-mechanical response, and simulations of these experiments require an accurate unreacted equation of state (EOS) in addition to the calibrated reaction rate. Other experiments are proposed to gain further insight into the detonation failure data, as well as to help discriminate between the role of the EOS and reaction rate in predicting the measured outcome.

  11. Convergent functional genomic studies of ω-3 fatty acids in stress reactivity, bipolar disorder and alcoholism.

    Science.gov (United States)

    Le-Niculescu, H; Case, N J; Hulvershorn, L; Patel, S D; Bowker, D; Gupta, J; Bell, R; Edenberg, H J; Tsuang, M T; Kuczenski, R; Geyer, M A; Rodd, Z A; Niculescu, A B

    2011-04-26

    Omega-3 fatty acids have been proposed as an adjuvant treatment option in psychiatric disorders. Given their other health benefits and their relative lack of toxicity, teratogenicity and side effects, they may be particularly useful in children and in females of child-bearing age, especially during pregnancy and postpartum. A comprehensive mechanistic understanding of their effects is needed. Here we report translational studies demonstrating the phenotypic normalization and gene expression effects of dietary omega-3 fatty acids, specifically docosahexaenoic acid (DHA), in a stress-reactive knockout mouse model of bipolar disorder and co-morbid alcoholism, using a bioinformatic convergent functional genomics approach integrating animal model and human data to prioritize disease-relevant genes. Additionally, to validate at a behavioral level the novel observed effects on decreasing alcohol consumption, we also tested the effects of DHA in an independent animal model, alcohol-preferring (P) rats, a well-established animal model of alcoholism. Our studies uncover sex differences, brain region-specific effects and blood biomarkers that may underpin the effects of DHA. Of note, DHA modulates some of the same genes targeted by current psychotropic medications, as well as increases myelin-related gene expression. Myelin-related gene expression decrease is a common, if nonspecific, denominator of neuropsychiatric disorders. In conclusion, our work supports the potential utility of omega-3 fatty acids, specifically DHA, for a spectrum of psychiatric disorders such as stress disorders, bipolar disorder, alcoholism and beyond.

  12. Global Plant Stress Signaling: Reactive Oxygen Species at the Cross-Road

    Directory of Open Access Journals (Sweden)

    Nasser eSewelam

    2016-02-01

    Full Text Available Current technologies have changed biology into a data-intensive field and significantly increased our understanding of signal transduction pathways in plants. However, global defense signaling networks in plants have not been established yet. Considering the apparent intricate nature of signaling mechanisms in plants (due to their sessile nature, studying the points at which different signaling pathways converge, rather than the branches, represents a good start to unravel global plant signaling networks. In this regard, growing evidence shows that the generation of reactive oxygen species (ROS is one of the most common plant responses to different stresses, representing a point at which various signaling pathways come together. In this review, the complex nature of plant stress signaling networks will be discussed. An emphasis on different signaling players with a specific attention to ROS as the primary source of the signaling battery in plants will be presented. The interactions between ROS and other signaling components, e.g. calcium, redox homeostasis, membranes, G-proteins, MAPKs, plant hormones and transcription factors will be assessed. A better understanding of the vital roles ROS are playing in plant signaling would help innovate new strategies to improve plant productivity under the circumstances of the increasing severity of environmental conditions and the high demand of food and energy worldwide

  13. Chemical sensing of plant stress at the ecosystem scale

    Directory of Open Access Journals (Sweden)

    T. Karl

    2008-09-01

    Full Text Available Significant ecosystem-scale emissions of methylsalicylate (MeSA, a semivolatile plant hormone thought to act as the mobile signal for systemic acquired resistance (SAR, were observed in an agroforest. Our measurements show that plant internal defence mechanisms can be activated in response to temperature stress and are modulated by water availability on large scales. Highest MeSA fluxes (up to 0.25 mg/m2/h were observed after plants experienced ambient night-time temperatures of ~7.5°C followed by a large daytime temperature increase (e.g. up to 22°C. Under these conditions estimated night-time leaf temperatures were as low as ~4.6°C, likely inducing a response to prevent chilling injury. Our observations imply that plant hormones can be a significant component of ecosystem scale volatile organic compound (VOC fluxes (e.g. as high as the total monoterpene (MT flux and therefore contribute to the missing VOC budget. If generalized to other ecosystems and different types of stresses these findings suggest that semivolatile plant hormones have been overlooked by investigations of the impact of biogenic VOCs on aerosol formation events in forested regions. Our observations show that the presence of MeSA in canopy air serves as an early chemical warning signal indicating ecosystem-scale stresses before visible damage becomes apparent. As a chemical metric, ecosystem emission measurements of MeSA in ambient air could therefore support field studies investigating factors that adversely affect plant growth.

  14. Assessing Stress-Induced Sleep Reactivity in College Students: The European Portuguese Version of the Ford Insomnia Response to Stress Test (FIRST)

    OpenAIRE

    Marques, Daniel Ruivo; Allen Gomes, Ana; Drake, Christopher Lawrence; Roth, Thomas; de Azevedo, Maria Helena Pinto

    2016-01-01

    Over the past few years, the comprehensive models of insomnia have exhibited impressive developments. However, there is scarce knowledge on predisposing or vulnerability factors for insomnia. One of the most promising constructs to aid in filling this gap is stress-induced sleep reactivity assessed through self-report. Our aim was to study the psychometric properties of the European Portuguese version of the Ford Insomnia Response to Stress Test (FIRST).

  15. Reported Exposure and Emotional Reactivity to Daily Stressors: The Roles of Adult-Age and Global Perceived Stress

    Science.gov (United States)

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

    2012-01-01

    A central goal of daily stress research is to identify resilience and vulnerability factors associated with exposure and reactivity to daily stressors. The current study examined how age differences and global perceptions of stress relate to exposure and emotional reactivity to daily stressors. Sixty-seven younger (Mage = 20) and 116 older (Mage = 80) adults completed a daily stress diary and measures of positive and negative affect on 6 days over a 14 day period. Participants also completed a measure of global perceived stress. Results revealed that reported exposure to daily stressors is reduced in old age, but that emotional reactivity to daily stressors did not differ between young and older adults. Global perceived stress was associated with greater reported exposure to daily stressors in old adults, and greater stress-related increases in negative affect in younger adults. Furthermore, across days on which daily stressors were reported, intraindividual variability in the number and severity of stressors reported was associated with increased negative affect, but only among younger adults. PMID:18361654

  16. Reported exposure and emotional reactivity to daily stressors: the roles of adult age and global perceived stress.

    Science.gov (United States)

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

    2008-03-01

    A central goal of daily stress research is to identify resilience and vulnerability factors associated with exposure and reactivity to daily stressors. The present study examined how age differences and global perceptions of stress relate to exposure and emotional reactivity to daily stressors. Sixty-seven younger (M age = 20) and 116 older (M age = 80) adults completed a daily stress diary and measures of positive and negative affect on 6 days over a 14-day period. Participants also completed a measure of global perceived stress. Results revealed that reported exposure to daily stressors is reduced in old age but that emotional reactivity to daily stressors did not differ between younger and older adults. Global perceived stress was associated with greater reported exposure to daily stressors in older adults and greater stress-related increases in negative affect in younger adults. Furthermore, across days on which daily stressors were reported, intraindividual variability in the number and severity of stressors reported was associated with increased negative affect, but only among younger adults. (c) 2008 APA, all rights reserved.

  17. Large-Scale Reactive Atomistic Simulation of Shock-induced Initiation Processes in Energetic Materials

    Science.gov (United States)

    Thompson, Aidan

    2013-06-01

    Initiation in energetic materials is fundamentally dependent on the interaction between a host of complex chemical and mechanical processes, occurring on scales ranging from intramolecular vibrations through molecular crystal plasticity up to hydrodynamic phenomena at the mesoscale. A variety of methods (e.g. quantum electronic structure methods (QM), non-reactive classical molecular dynamics (MD), mesoscopic continuum mechanics) exist to study processes occurring on each of these scales in isolation, but cannot describe how these processes interact with each other. In contrast, the ReaxFF reactive force field, implemented in the LAMMPS parallel MD code, allows us to routinely perform multimillion-atom reactive MD simulations of shock-induced initiation in a variety of energetic materials. This is done either by explicitly driving a shock-wave through the structure (NEMD) or by imposing thermodynamic constraints on the collective dynamics of the simulation cell e.g. using the Multiscale Shock Technique (MSST). These MD simulations allow us to directly observe how energy is transferred from the shockwave into other processes, including intramolecular vibrational modes, plastic deformation of the crystal, and hydrodynamic jetting at interfaces. These processes in turn cause thermal excitation of chemical bonds leading to initial chemical reactions, and ultimately to exothermic formation of product species. Results will be presented on the application of this approach to several important energetic materials, including pentaerythritol tetranitrate (PETN) and ammonium nitrate/fuel oil (ANFO). In both cases, we validate the ReaxFF parameterizations against QM and experimental data. For PETN, we observe initiation occurring via different chemical pathways, depending on the shock direction. For PETN containing spherical voids, we observe enhanced sensitivity due to jetting, void collapse, and hotspot formation, with sensitivity increasing with void size. For ANFO, we

  18. The influence of forgiveness and apology on cardiovascular reactivity and recovery in response to mental stress.

    Science.gov (United States)

    Whited, Matthew C; Wheat, Amanda L; Larkin, Kevin T

    2010-08-01

    To investigate the relation between forgiveness and apology as they relate to cardiovascular reactivity and recovery, 29 men and 50 women were exposed to an interpersonal transgression (i.e., verbal harassment) while performing a serial subtraction task. Participants were categorized into high and low forgiveness groups based on scores on the forgiving personality scale. Following the task, approximately half of the participants received an apology from the experimenter for his/her comments during the task. Although no group differences in cardiovascular reactivity were observed during the serial subtraction task, persons high in forgiveness displayed more rapid diastolic and mean arterial blood pressure recovery than persons low in forgiveness. In response to the apology, participants displayed greater high frequency heart rate variability recovery compared to those who did not receive an apology. A significant apology x sex interaction was observed for diastolic blood pressure and mean arterial blood pressure. Women who received an apology exhibited faster recovery from the transgression than women who did not receive an apology. In contrast, men who received an apology exhibited delayed recovery from the transgression compared to men who did not receive an apology. These results indicate that there are potentially healthful benefits to forgiveness and apology, but the relation is influenced by situation and by sex.

  19. Water stress strengthens mutualism among ants, trees, and scale insects.

    Directory of Open Access Journals (Sweden)

    Elizabeth G Pringle

    2013-11-01

    Full Text Available Abiotic environmental variables strongly affect the outcomes of species interactions. For example, mutualistic interactions between species are often stronger when resources are limited. The effect might be indirect: water stress on plants can lead to carbon stress, which could alter carbon-mediated plant mutualisms. In mutualistic ant-plant symbioses, plants host ant colonies that defend them against herbivores. Here we show that the partners' investments in a widespread ant-plant symbiosis increase with water stress across 26 sites along a Mesoamerican precipitation gradient. At lower precipitation levels, Cordia alliodora trees invest more carbon in Azteca ants via phloem-feeding scale insects that provide the ants with sugars, and the ants provide better defense of the carbon-producing leaves. Under water stress, the trees have smaller carbon pools. A model of the carbon trade-offs for the mutualistic partners shows that the observed strategies can arise from the carbon costs of rare but extreme events of herbivory in the rainy season. Thus, water limitation, together with the risk of herbivory, increases the strength of a carbon-based mutualism.

  20. Water Stress Strengthens Mutualism Among Ants, Trees, and Scale Insects

    Science.gov (United States)

    Pringle, Elizabeth G.; Akçay, Erol; Raab, Ted K.; Dirzo, Rodolfo; Gordon, Deborah M.

    2013-01-01

    Abiotic environmental variables strongly affect the outcomes of species interactions. For example, mutualistic interactions between species are often stronger when resources are limited. The effect might be indirect: water stress on plants can lead to carbon stress, which could alter carbon-mediated plant mutualisms. In mutualistic ant–plant symbioses, plants host ant colonies that defend them against herbivores. Here we show that the partners' investments in a widespread ant–plant symbiosis increase with water stress across 26 sites along a Mesoamerican precipitation gradient. At lower precipitation levels, Cordia alliodora trees invest more carbon in Azteca ants via phloem-feeding scale insects that provide the ants with sugars, and the ants provide better defense of the carbon-producing leaves. Under water stress, the trees have smaller carbon pools. A model of the carbon trade-offs for the mutualistic partners shows that the observed strategies can arise from the carbon costs of rare but extreme events of herbivory in the rainy season. Thus, water limitation, together with the risk of herbivory, increases the strength of a carbon-based mutualism. PMID:24223521

  1. Water stress strengthens mutualism among ants, trees, and scale insects.

    Science.gov (United States)

    Pringle, Elizabeth G; Akçay, Erol; Raab, Ted K; Dirzo, Rodolfo; Gordon, Deborah M

    2013-11-01

    Abiotic environmental variables strongly affect the outcomes of species interactions. For example, mutualistic interactions between species are often stronger when resources are limited. The effect might be indirect: water stress on plants can lead to carbon stress, which could alter carbon-mediated plant mutualisms. In mutualistic ant-plant symbioses, plants host ant colonies that defend them against herbivores. Here we show that the partners' investments in a widespread ant-plant symbiosis increase with water stress across 26 sites along a Mesoamerican precipitation gradient. At lower precipitation levels, Cordia alliodora trees invest more carbon in Azteca ants via phloem-feeding scale insects that provide the ants with sugars, and the ants provide better defense of the carbon-producing leaves. Under water stress, the trees have smaller carbon pools. A model of the carbon trade-offs for the mutualistic partners shows that the observed strategies can arise from the carbon costs of rare but extreme events of herbivory in the rainy season. Thus, water limitation, together with the risk of herbivory, increases the strength of a carbon-based mutualism.

  2. Emotional Reactivity to Network Stress in Middle and Late Adulthood: The Role of Childhood Parental Emotional Abuse and Support

    Science.gov (United States)

    Poon, Cecilia Y. M.; Knight, Bob G.

    2012-01-01

    Purpose: This study examined whether recalled childhood parental emotional abuse and support were associated with emotional reactivity to network stress among middle-aged and older adults. Design and Methods: Hypotheses were tested by performing 2-level multilevel modeling analysis on 787 participants aged 33-83 who participated in the Daily…

  3. Procoagulant reactivity to laboratory acute mental stress in Africans and Caucasians, and its relation to depressive symptoms: the SABPA study.

    Science.gov (United States)

    von Känel, R; Hamer, M; Malan, N T; Scheepers, K; Meiring, M; Malan, L

    2013-11-01

    The risk of cardiovascular disease is dramatically increasing in Africans (black). The prothrombotic stress response contributes to atherothrombotic disease and is modulated by depressive symptoms. We examined coagulation reactivity to acute mental stress and its relation to psychological well-being in Africans relative to Caucasians (white). A total of 102 African and 165 Caucasian school teachers underwent the Stroop Color-Word Conflict test. Circulating levels of von Willebrand factor (VWF) antigen, fibrinogen, and D-dimer were measured before and after the Stroop. Cardiovascular reactivity measures were also obtained. All participants completed the Patient Health Questionnaire-9 and the General Health Questionnaire-28 for the assessment of depressive symptoms and total psychological distress, respectively. After controlling for covariates, resting levels of VWF, fibrinogen, and D-dimer were higher in Africans than in Caucasians (all p-values ≤0.006). Depressive symptoms and psychological distress were not significantly associated with resting coagulation measures. Stress reactivity in VWF (pstress when compared with Caucasians. Ethnic differences in the vascular adrenergic stress response might partially explain this finding. Depressive symptoms were associated with exaggerated VWF reactivity in Africans relative to Caucasians. The clinical implications of these findings for Africans need further study.

  4. Regulatory Behaviors and Stress Reactivity among Infants at High Risk for Fetal Alcohol Spectrum Disorders: An Exploratory Study

    Science.gov (United States)

    Jirikowic, Tracy; Chen, Maida; Nash, Jennifer; Gendler, Beth; Olson, Heather Carmichael

    2016-01-01

    Introduction: This article examines regulatory behaviors and physiological stress reactivity among 6-15 month-old infants with moderate to heavy prenatal alcohol exposure (PAE), a group at very high risk for fetal alcohol spectrum disorders and self-regulation impairments, compared to low risk infants with no/low exposure. Participants: Eighteen…

  5. SKA2 Methylation is Involved in Cortisol Stress Reactivity and Predicts the Development of Post-Traumatic Stress Disorder (PTSD) after Military Deployment

    NARCIS (Netherlands)

    Boks, Marco P.; Rutten, Bart P F; Geuze, Elbert; Houtepen, Lotte C.; Vermetten, Eric; Kaminsky, Zachary; Vinkers, Christiaan H.

    2016-01-01

    Genomic variation in the SKA2 gene has recently been identified as a promising suicide biomarker. In light of its role in glucocorticoid receptor transactivation, we investigated whether SKA2 DNA methylation influences cortisol stress reactivity and is involved in the development of post-traumatic

  6. Stress analysis and scaling studies of corium crusts

    International Nuclear Information System (INIS)

    Feng, Z.; Engelstad, R.L.; Lovell, E.G.; Corradini, M.L.

    1992-01-01

    In the event of a severe accident in a LWR, water may be input to cool the molten mixture of fuel and concrete. A number of structural models are developed and used to predict whether a crust will be formed and remain stable between the melt and water. Bending stresses and membrane stresses due to pressure loadings and the temperature differential are considered in the analyses to investigate the stability of the crust as a function of the time, thickness and span. The results from parametric studies show the conditions under which a crust could develop, and how such structural models could be used to determine scaling effects and provide correlations to prototypic accident situations. (orig.)

  7. Mindfulness training and stress reactivity in substance abuse: results from a randomized, controlled stage I pilot study.

    Science.gov (United States)

    Brewer, Judson A; Sinha, Rajita; Chen, Justin A; Michalsen, Ravenna N; Babuscio, Theresa A; Nich, Charla; Grier, Aleesha; Bergquist, Keri L; Reis, Deidre L; Potenza, Marc N; Carroll, Kathleen M; Rounsaville, Bruce J

    2009-01-01

    Stress is important in substance use disorders (SUDs). Mindfulness training (MT) has shown promise for stress-related maladies. No studies have compared MT to empirically validated treatments for SUDs. The goals of this study were to assess MT compared to cognitive behavioral therapy (CBT) in substance use and treatment acceptability, and specificity of MT compared to CBT in targeting stress reactivity. Thirty-six individuals with alcohol and/or cocaine use disorders were randomly assigned to receive group MT or CBT in an outpatient setting. Drug use was assessed weekly. After treatment, responses to personalized stress provocation were measured. Fourteen individuals completed treatment. There were no differences in treatment satisfaction or drug use between groups. The laboratory paradigm suggested reduced psychological and physiological indices of stress during provocation in MT compared to CBT. This pilot study provides evidence of the feasibility of MT in treating SUDs and suggests that MT may be efficacious in targeting stress.

  8. Release of Aged Contaminants from weathered sediments: Effects of sorbate speciation on scaling of reactive transport

    Energy Technology Data Exchange (ETDEWEB)

    Chorover, Jon [Univ. of Arizona, Tucson, AZ (United States); Perdrial, Nico [Univ. of Arizona, Tucson, AZ (United States); Mueller, Karl [Pennsylvania State Univ., University Park, PA (United States); Strepka, Caleb [Pennsylvania State Univ., University Park, PA (United States); O' Day, Peggy [Univ. of California, Merced, CA (United States); Rivera, Nelson [Univ. of California, Merced, CA (United States); Um, Wooyong [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Chang, Hyun-Shik [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Steefel, Carl [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Thompson, Aaron [Univ. of Georgia, Athens, GA (United States)

    2012-08-14

    Hanford sediments impacted by hyperalkaline high level radioactive waste have undergone incongruent silicate mineral weathering concurrent with contaminant uptake (Chorover et al., 2008). In this project, we studied the impact of background pore water (BPW) on strontium, cesium and iodine desorption and transport in Hanford sediments that were experimentally weathered by contact with simulated hyperalkaline tank waste leachate (STWL) solutions. Using those lab-weathered Hanford sediments (HS) and model precipitates formed during nucleation from homogeneous STWL solutions (HN), we (i) provided thorough characterization of reaction products over a matrix of field-relevant gradients in contaminant concentration, PCO2, and reaction time; (ii) improved molecular-scale understanding of how sorbate speciation controls contaminant desorption from weathered sediments upon removal of caustic sources; and (iii) developed a mechanistic, predictive model of meso- to field-scale contaminant reactive transport under these conditions. Below, we provide some detailed descriptions of our results from this three year study, recently completed following a one-year no cost extension.

  9. Release of aged contaminants from weathered sediments: Effects of sorbate speciation on scaling of reactive transport

    Energy Technology Data Exchange (ETDEWEB)

    Chorover, Jon; Perdrial, Nico; Mueller, Karl; Strepka, Caleb; O’Day, Peggy; Rivera, Nelson; Um, Wooyong; Chang, Hyun-Shik; Steefel, Carl; Thompson, Aaron

    2012-11-05

    Hanford sediments impacted by hyperalkaline high level radioactive waste have undergone incongruent silicate mineral weathering concurrent with contaminant uptake. In this project, we studied the impact of background pore water (BPW) on strontium, cesium and iodine desorption and transport in Hanford sediments that were experimentally weathered by contact with simulated hyperalkaline tank waste leachate (STWL) solutions. Using those lab-weathered Hanford sediments (HS) and model precipitates formed during nucleation from homogeneous STWL solutions (HN), we (i) provided thorough characterization of reaction products over a matrix of field-relevant gradients in contaminant concentration, partial pressure of carbon dioxide, and reaction time; (ii) improved molecular-scale understanding of how sorbate speciation controls contaminant desorption from weathered sediments upon removal of caustic sources; and (iii) developed a mechanistic, predictive model of meso- to field-scale contaminant reactive transport under these conditions. In this final report, we provide detailed descriptions of our results from this three-year study, completed in 2012 following a one-year no cost extension.

  10. Cardiovascular reactivity to a marital conflict version of the Trier social stress test in intimate partner violence perpetrators.

    Science.gov (United States)

    Romero-Martínez, Angel; Nunes-Costa, Rui; Lila, Marisol; González-Bono, Esperanza; Moya-Albiol, Luis

    2014-07-01

    Intimate partner violence (IPV) perpetrators have been categorized into two groups based on their heart rate (HR) reactivity to stress following Gottman's studies. Overall, type I perpetrators tend to show autonomic underarousal, whereas type II or reactive perpetrators present a hyper-reactivity in anticipation of stress. In this study, changes in HR, pre-ejection period (PEP), vagal ratio as well as psychological state variables (anxiety and anger) in response to stress were assessed, comparing a group of type II IPV perpetrators (based on violence reports and psychological assessment; n = 17; mean age = 37) with non-violent controls (n = 17; mean age = 35) using modified version of the Trier Social Stress Test. IPV perpetrators had higher HRs and lower vagal ratios than controls, particularly during the recovery period. Moreover, the former presented shorter PEPs than controls. There were no differences between groups in the magnitude of response of the HR, PEP or vagal ratio. High baseline anxiety and anger were associated with an HR increase during the preparation time in IPV perpetrators but not in controls. These findings indicate a different cardiovascular pattern of response to psychosocial stress in IPV perpetrators, especially during recovery. Thus, they contribute to understanding the biological functioning of violence sub-types, supporting the validity of cardiovascular measures as diagnostic indicators for IPV classification.

  11. Panic and comorbid depression and their associations with stress reactivity, interoceptive awareness and interoceptive accuracy of various bioparameters.

    Science.gov (United States)

    Limmer, Jan; Kornhuber, Johannes; Martin, Alexandra

    2015-10-01

    While current theories on perception of interoceptive signals suggest impaired interoceptive processing in psychiatric disorders such as panic disorder or depression, heart-rate (HR) interoceptive accuracy (IAc) of panic patients under resting conditions is superior to that of healthy controls. Thus, in this study, we chose to assess further physiological parameters and comorbid depression in order to get information on how these potentially conflicting findings are linked together. We used a quasi-experimental laboratory design which included multi-parametric physiological data collection of 40 panic subjects and 53 matched no-panic controls, as well as experimental induction of stress and relaxation over a time-course. Stress reactivity, interoceptive awareness (IAw; from the Body Perception Questionnaire (BPQ)) and IAc (as correlation between self-estimation and physiological data) were major outcome variables. Self-estimation of bioparametrical change was measured via numeric rating scales. Panic subjects had stronger HR-reaction and more accurate HR-interoception. Concurrently, though, their IAc of skin conductance level, pulse amplitude and breathing amplitude was significantly lower than that of the control group. Interestingly, comorbid depression was found to be associated with increased IAw but attenuated IAc. Demand characteristics and a categorical approach to panic confine the results. The potentially conflicting findings coalesce, as panic was associated with an increase of the ability to perceive the fear-related parameter and a simultaneous decrease of the ability to perceive other parameters. The superordinate integration of afferent signals might be impaired. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  12. Cardiovascular Reactivity in Patients With Major Depressive Disorder With High- or Low-Level Depressive Symptoms: A Cross-Sectional Comparison of Cardiovascular Reactivity to Laboratory-Induced Mental Stress.

    Science.gov (United States)

    Wang, Mei-Yeh; Chiu, Chen-Huan; Lee, Hsin-Chien; Su, Chien-Tien; Tsai, Pei-Shan

    2016-03-01

    Depression increases the risk of adverse cardiac events. Cardiovascular reactivity is defined as the pattern of cardiovascular responses to mental stress. An altered pattern of cardiovascular reactivity is an indicator of subsequent cardiovascular disease. Because depression and adverse cardiac events may have a dose-dependent association, this study examined the differences in cardiovascular reactivity to mental stress between patients with major depressive disorder (MDD) with high depression levels and those with low depression levels. Moreover, autonomic nervous system regulation is a highly plausible biological mechanism for the pattern of cardiovascular reactivity to mental stress. The association between cardiovascular reactivity and parameters of heart rate variability (HRV), an index for quantifying autonomic nervous system activity modulation, was thus examined. This study included 88 patients with MDD. HRV was measured before stress induction. The Stroop Color and Word Test and mirror star-tracing task were used to induce mental stress. We observed no significant association between depressive symptom level and any of the cardiovascular reactivity parameters. Cardiovascular reactivity to mental stress was comparable between patients with MDD with high-level depressive symptoms and those with low-level depressive symptoms. After adjusting for confounding variables, the high-frequency domain of HRV was found to be an independent predictor of the magnitude of heart rate reactivity (β = -.33, p = .002). In conclusion, the magnitude of cardiovascular reactivity may be independent of depression severity in patients with MDD. The autonomic regulation of cardiovascular responses to mental stress primarily influences heart rate reactivity in patients with MDD. © The Author(s) 2015.

  13. Association of BDNF Val66Met polymorphism with HPA and SAM axis reactivity to psychological and physical stress.

    Science.gov (United States)

    Tsuru, Jusen; Tanaka, Yoshihiro; Ishitobi, Yoshinobu; Maruyama, Yoshihiro; Inoue, Ayako; Kawano, Aimi; Ikeda, Rie; Ando, Tomoko; Oshita, Harumi; Aizawa, Saeko; Masuda, Koji; Higuma, Haruka; Kanehisa, Masayuki; Ninomiya, Taiga; Akiyoshi, Jotaro

    2014-01-01

    Decreased expression of brain-derived neurotrophic factor (BDNF) is implicated in enhanced stress responses. The BDNF Val66Met polymorphism is associated with psychological changes; for example, carriers of the Met allele exhibit increased harm avoidance as well as a higher prevalence of depression and anxiety disorder. To analyze the effects of BDNF Val66Met on stress responses, we tested 226 university students (88 women and 138 men) using a social stress procedure (Trier Social Stress Test [TSST]) and an electrical stimulation stress test. Stress indices were derived from repeated measurements of salivary α-amylase, salivary cortisol, heart rate, and psychological testing during the stress tests. All subjects were genotyped for the Val66Met polymorphism (G196A). A significant three-way interaction (time [3 levels] × BDNF [Val/Val, Val/Met, Met/Met]; PBDNF had different effects on hypothalamic-pituitary-adrenocortical axis reactivity but not on sympathetic adrenomedullary reactivity in TSST and electrical stimulation tests.

  14. Accounting for the Decreasing Reaction Potential of Heterogeneous Aquifers in a Stochastic Framework of Aquifer-Scale Reactive Transport

    Science.gov (United States)

    Loschko, Matthias; Wöhling, Thomas; Rudolph, David L.; Cirpka, Olaf A.

    2018-01-01

    Many groundwater contaminants react with components of the aquifer matrix, causing a depletion of the aquifer's reactivity with time. We discuss conceptual simplifications of reactive transport that allow the implementation of a decreasing reaction potential in reactive-transport simulations in chemically and hydraulically heterogeneous aquifers without relying on a fully explicit description. We replace spatial coordinates by travel-times and use the concept of relative reactivity, which represents the reaction-partner supply from the matrix relative to a reference. Microorganisms facilitating the reactions are not explicitly modeled. Solute mixing is neglected. Streamlines, obtained by particle tracking, are discretized in travel-time increments with variable content of reaction partners in the matrix. As exemplary reactive system, we consider aerobic respiration and denitrification with simplified reaction equations: Dissolved oxygen undergoes conditional zero-order decay, nitrate follows first-order decay, which is inhibited in the presence of dissolved oxygen. Both reactions deplete the bioavailable organic carbon of the matrix, which in turn determines the relative reactivity. These simplifications reduce the computational effort, facilitating stochastic simulations of reactive transport on the aquifer scale. In a one-dimensional test case with a more detailed description of the reactions, we derive a potential relationship between the bioavailable organic-carbon content and the relative reactivity. In a three-dimensional steady-state test case, we use the simplified model to calculate the decreasing denitrification potential of an artificial aquifer over 200 years in an ensemble of 200 members. We demonstrate that the uncertainty in predicting the nitrate breakthrough in a heterogeneous aquifer decreases with increasing scale of observation.

  15. Validation of Bengali perceived stress scale among LGBT population.

    Science.gov (United States)

    Mozumder, Muhammad Kamruzzaman

    2017-08-29

    Lesbian, gay, bisexual and transgender (LGBT) population encounter more stressful life circumstances compared to general population. Perceived Stress Scale (PSS) can be a useful tool for measuring their stress. However, psychometric properties of PSS have never been tested on LGBT population. This cross sectional study employed a two-stage sampling strategy to collect data from 296 LGBT participants from six divisional districts of Bangladesh. Exploratory (EFA) and confirmatory factor analysis (CFA) were carried out on PSS 10 along with analysis of reliability and validity. EFA revealed a two-factor structure of PSS for LGBT population explaining 43.55% - 51.45% of total variance. This measurement model was supported by multiple fit indices during CFA. Acceptable Cronbach's alpha indicated internal consistency reliability and high correlations with Self Reporting Questionnaire 20 demonstrated construct validity of PSS 10 for LGBT population. This study provided evidence of satisfactory psychometric properties of Bengali PSS 10 in terms of factor structure, internal consistency and validity among LGBT population.

  16. A single session of hatha yoga improves stress reactivity and recovery after an acute psychological stress task-A counterbalanced, randomized-crossover trial in healthy individuals.

    Science.gov (United States)

    Benvenutti, Mateus J; Alves, Eduardo da Sliva; Michael, Scott; Ding, Ding; Stamatakis, Emmanuel; Edwards, Kate M

    2017-12-01

    Yoga is promoted as an anti-stress activity, however, little is known about the mechanisms through which it acts. The present study investigated the acute effects of a hatha yoga session, displayed on a video, on the response to and recovery from an acute psychological stressor. Twenty-four healthy young adults took part in a counterbalanced, randomized-crossover trial, with a yoga and a control condition (watching TV). Participants attended the laboratory in the afternoon on two days and each session comprised a baseline, control or yoga task, stress task and recovery. Blood pressure (BP), heart rate (HR) and salivary cortisol responses were measured. State cognitive- and somatic-anxiety along with self-confidence were assessed before and after the stressor. Although no difference in the BP or HR responses to stress were found between conditions, systolic BP (p=0.047) and diastolic BP (p=0.018) recovery from stress were significantly accelerated and salivary cortisol reactivity was significantly lower (p=0.01) in the yoga condition. A yoga session also increased self-confidence (p=0.006) in preparation for the task and after completion. Moreover, self-confidence reported after the stress task was considered debilitative towards performance in the control condition, but remained facilitative in the yoga condition. Our results show that a single video-instructed session of hatha yoga was able to improve stress reactivity and recovery from an acute stress task in healthy individuals. These positive preliminary findings encourage further investigation in at-risk populations in which the magnitude of effects may be greater, and support the use of yoga for stress reactivity and recovery. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Task stressfulness moderates the effects of verbal person centeredness on cardiovascular reactivity: a dual-process account of the reactivity hypothesis.

    Science.gov (United States)

    Bodie, Graham D

    2012-01-01

    This study sought to investigate the impact of person-centered comfort on cardiovascular reactivity and to test a recently developed dual-process theory of supportive message outcomes proposing that the impact of supportive communication is moderated by the motivation and ability to attend to message content. Participants (n = 179) completed a public speaking task that served to experimentally manipulate stress. During the preparation period, instant messages containing either low or high person-centered messages or containing no imbedded supportive message were sent. Results indicated that, in line with theoretical predictions, message content did influence mean arterial pressure and heart rate for participants exposed to moderate but not to low or high stress. Results are discussed in terms of the dual-process theory of supportive message outcomes, and the discussion offers both theoretical and practical implications of the research.

  18. Release of proteins from intact chloroplasts induced by reactive oxygen species during biotic and abiotic stress.

    Science.gov (United States)

    Kwon, Kwang-Chul; Verma, Dheeraj; Jin, Shuangxia; Singh, Nameirakpam D; Daniell, Henry

    2013-01-01

    Plastids sustain life on this planet by providing food, feed, essential biomolecules and oxygen. Such diverse metabolic and biosynthetic functions require efficient communication between plastids and the nucleus. However, specific factors, especially large molecules, released from plastids that regulate nuclear genes have not yet been fully elucidated. When tobacco and lettuce transplastomic plants expressing GFP within chloroplasts, were challenged with Erwinia carotovora (biotic stress) or paraquat (abiotic stress), GFP was released into the cytoplasm. During this process GFP moves gradually towards the envelope, creating a central red zone of chlorophyll fluorescence. GFP was then gradually released from intact chloroplasts into the cytoplasm with an intact vacuole and no other visible cellular damage. Different stages of GFP release were observed inside the same cell with a few chloroplasts completely releasing GFP with detection of only red chlorophyll fluorescence or with no reduction in GFP fluorescence or transitional steps between these two phases. Time lapse imaging by confocal microscopy clearly identified sequence of these events. Intactness of chloroplasts during this process was evident from chlorophyll fluorescence emanated from thylakoid membranes and in vivo Chla fluorescence measurements (maximum quantum yield of photosystem II) made before or after infection with pathogens to evaluate their photosynthetic competence. Hydrogen peroxide and superoxide anion serve as signal molecules for generation of reactive oxygen species and Tiron, scavenger of superoxide anion, blocked release of GFP from chloroplasts. Significant increase in ion leakage in the presence of paraquat and light suggests changes in the chloroplast envelope to facilitate protein release. Release of GFP-RC101 (an antimicrobial peptide), which was triggered by Erwinia infection, ceased after conferring protection, further confirming this export phenomenon. These results suggest a

  19. Release of proteins from intact chloroplasts induced by reactive oxygen species during biotic and abiotic stress.

    Directory of Open Access Journals (Sweden)

    Kwang-Chul Kwon

    Full Text Available Plastids sustain life on this planet by providing food, feed, essential biomolecules and oxygen. Such diverse metabolic and biosynthetic functions require efficient communication between plastids and the nucleus. However, specific factors, especially large molecules, released from plastids that regulate nuclear genes have not yet been fully elucidated. When tobacco and lettuce transplastomic plants expressing GFP within chloroplasts, were challenged with Erwinia carotovora (biotic stress or paraquat (abiotic stress, GFP was released into the cytoplasm. During this process GFP moves gradually towards the envelope, creating a central red zone of chlorophyll fluorescence. GFP was then gradually released from intact chloroplasts into the cytoplasm with an intact vacuole and no other visible cellular damage. Different stages of GFP release were observed inside the same cell with a few chloroplasts completely releasing GFP with detection of only red chlorophyll fluorescence or with no reduction in GFP fluorescence or transitional steps between these two phases. Time lapse imaging by confocal microscopy clearly identified sequence of these events. Intactness of chloroplasts during this process was evident from chlorophyll fluorescence emanated from thylakoid membranes and in vivo Chla fluorescence measurements (maximum quantum yield of photosystem II made before or after infection with pathogens to evaluate their photosynthetic competence. Hydrogen peroxide and superoxide anion serve as signal molecules for generation of reactive oxygen species and Tiron, scavenger of superoxide anion, blocked release of GFP from chloroplasts. Significant increase in ion leakage in the presence of paraquat and light suggests changes in the chloroplast envelope to facilitate protein release. Release of GFP-RC101 (an antimicrobial peptide, which was triggered by Erwinia infection, ceased after conferring protection, further confirming this export phenomenon. These

  20. Effects of exercise training on stress-induced vascular reactivity alterations: role of nitric oxide and prostanoids

    Directory of Open Access Journals (Sweden)

    Thiago Bruder-Nascimento

    2015-06-01

    Full Text Available Background: Physical exercise may modify biologic stress responses. Objective: To investigate the impact of exercise training on vascular alterations induced by acute stress, focusing on nitric oxide and cyclooxygenase pathways. Method: Wistar rats were separated into: sedentary, trained (60-min swimming, 5 days/week during 8 weeks, carrying a 5% body-weight load, stressed (2 h-immobilization, and trained/stressed. Response curves for noradrenaline, in the absence and presence of L-NAME or indomethacin, were obtained in intact and denuded aortas (n=7-10. Results: None of the procedures altered the denuded aorta reactivity. Intact aortas from stressed, trained, and trained/stressed rats showed similar reduction in noradrenaline maximal responses (sedentary 3.54±0.15, stressed 2.80±0.10*, trained 2.82±0.11*, trained/stressed 2.97± 0.21*, *P<0.05 relate to sedentary. Endothelium removal and L-NAME abolished this hyporeactivity in all experimental groups, except in trained/stressed rats that showed a partial aorta reactivity recovery in L-NAME presence (L-NAME: sedentary 5.23±0,26#, stressed 5.55±0.38#, trained 5.28±0.30#, trained/stressed 4.42±0.41, #P<0.05 related to trained/stressed. Indomethacin determined a decrease in sensitivity (EC50 in intact aortas of trained rats without abolishing the aortal hyporeactivity in trained, stressed, and trained/stressed rats. Conclusions: Exercise-induced vascular adaptive response involved an increase in endothelial vasodilator prostaglandins and nitric oxide. Stress-induced vascular adaptive response involved an increase in endothelial nitric oxide. Beside the involvement of the endothelial nitric oxide pathway, the vascular response of trained/stressed rats involved an additional mechanism yet to be elucidated. These findings advance on the understanding of the vascular processes after exercise and stress alone and in combination.

  1. Sleep deprived and sweating it out: the effects of total sleep deprivation on skin conductance reactivity to psychosocial stress.

    Science.gov (United States)

    Liu, Jean C J; Verhulst, Silvan; Massar, Stijn A A; Chee, Michael W L

    2015-01-01

    We examined how sleep deprivation alters physiological responses to psychosocial stress by evaluating changes in skin conductance. Between-subjects design with one group allocated to 24 h of total sleep deprivation and the other to rested wakefulness. The study took place in a research laboratory. Participants were 40 healthy young adults recruited from a university. Sleep deprivation and feedback. Electrodermal activity was monitored while participants completed a difficult perceptual task with false feedback. All participants showed increased skin conductance levels following stress. However, compared to well-rested participants, sleep deprived participants showed higher skin conductance reactivity with increasing stress levels. Our results suggest that sleep deprivation augments allostatic responses to increasing psychosocial stress. Consequentially, we propose sleep loss as a risk factor that can influence the pathogenic effects of stress. © 2014 Associated Professional Sleep Societies, LLC.

  2. Impact of Adverse Childhood Experiences on Psychotic-Like Symptoms and Stress Reactivity in Daily Life in Nonclinical Young Adults.

    Directory of Open Access Journals (Sweden)

    Paula Cristóbal-Narváez

    Full Text Available There is increasing interest in elucidating the association of different childhood adversities with psychosis-spectrum symptoms as well as the mechanistic processes involved. This study used experience sampling methodology to examine (i associations of a range of childhood adversities with psychosis symptom domains in daily life; (ii whether associations of abuse and neglect with symptoms are consistent across self-report and interview methods of trauma assessment; and (iii the role of different adversities in moderating affective, psychotic-like, and paranoid reactivity to situational and social stressors.A total of 206 nonclinical young adults were administered self-report and interview measures to assess childhood abuse, neglect, bullying, losses, and general traumatic events. Participants received personal digital assistants that signaled them randomly eight times daily for one week to complete questionnaires about current experiences, including symptoms, affect, and stress.Self-reported and interview-based abuse and neglect were associated with psychotic-like and paranoid symptoms, whereas only self-reported neglect was associated with negative-like symptoms. Bullying was associated with psychotic-like symptoms. Losses and general traumatic events were not directly associated with any of the symptom domains. All the childhood adversities were associated with stress reactivity in daily life. Interpersonal adversities (abuse, neglect, bullying, and losses moderated psychotic-like and/or paranoid reactivity to situational and social stressors, whereas general traumatic events moderated psychotic-like reactivity to situational stress. Also, different interpersonal adversities exacerbated psychotic-like and/or paranoid symptoms in response to distinct social stressors.The present study provides a unique examination of how childhood adversities impact the expression of spectrum symptoms in the real world and lends support to the notion that

  3. Relationship between obesity, negative affect and basal heart rate in predicting heart rate reactivity to psychological stress among adolescents.

    Science.gov (United States)

    Park, Andres E; Huynh, Pauline; Schell, Anne M; Baker, Laura A

    2015-08-01

    Reduced cardiovascular responses to psychological stressors have been found to be associated with both obesity and negative affect in adults, but have been less well studied in children and adolescent populations. These findings have most often been interpreted as reflecting reduced sympathetic nervous system response, perhaps associated with heightened baseline sympathetic activation among the obese and those manifesting negative affect. However, obesity and negative affect may themselves be correlated, raising the question of whether they both independently affect cardiovascular reactivity. The present study thus examined the separate effects of obesity and negative affect on both cardiovascular and skin conductance responses to stress (e.g., during a serial subtraction math task) in adolescents, while controlling for baseline levels of autonomic activity during rest. Both obesity and negative affect had independent and negative associations with cardiovascular reactivity, such that reduced stress responses were apparent for obese adolescents and those with high levels of negative affect. In contrast, neither obesity nor negative affect was related to skin conductance responses to stress, implicating specifically noradrenergic mechanisms rather than sympathetic mechanisms generally as being deficient. Moreover, baseline heart rate was unrelated to obesity in this sample, which suggests that heightened baseline of sympathetic activity is not necessary for the reduced cardiovascular reactivity to stress. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. The role of oxidative stress in EBV lytic reactivation, radioresistance and the potential preventive and therapeutic implications.

    Science.gov (United States)

    Hu, Jianmin; Li, Hongde; Luo, Xiangjian; Li, Yueshuo; Bode, Ann; Cao, Ya

    2017-11-01

    Epstein-Barr virus (EBV) is an important cancer causing virus. Cancer associated with EBV account for approximately 1.5% of all cancers, and represent 1.8% of all cancer deaths worldwide. EBV reactivation plays an important role in the development of EBV-related diseases and is closely related with patients' survival and clinical stages of EBV-related cancers. The therapy regarding to EBV-related cancers is very urgent, especially in endemic areas. Generating oxidative stress is a critical mechanism by which host cells defend against infection by virus. In addition, ROS-mediated oxidative stress plays a significant but paradoxical role acting as a "double-edged sword" to regulate cellular response to radiation, which is the main therapy strategy for EBV-related cancers, especially nasopharyngeal carcinoma. Therefore, in this review we primarily discuss the possible interplay among the oxidative stress, EBV lytic reactivation and radioresistance. Understanding the role of oxidative stress in EBV lytic reactivation and radioresistance will assist in the development of effective strategies for prevention and treatment of EBV-related cancers. © 2017 UICC.

  5. Reactive transport modelling of groundwater chemistry in a chalk aquifer at the watershed scale.

    Science.gov (United States)

    Mangeret, A; De Windt, L; Crançon, P

    2012-09-01

    This study investigates thermodynamics and kinetics of water-rock interactions in a carbonate aquifer at the watershed scale. A reactive transport model is applied to the unconfined chalk aquifer of the Champagne Mounts (France), by considering both the chalk matrix and the interconnected fracture network. Major element concentrations and main chemical parameters calculated in groundwater and their evolution along flow lines are in fair agreement with field data. A relative homogeneity of the aquifer baseline chemistry is rapidly reached in terms of pH, alkalinity and Ca concentration since calcite equilibrium is achieved over the first metres of the vadose zone. However, incongruent chalk dissolution slowly releases Ba, Mg and Sr in groundwater. Introducing dilution effect by rainwater infiltration and a local occurrence of dolomite improves the agreement between modelling and field data. The dissolution of illite and opal-CT, controlling K and SiO(2) concentrations in the model, can be approximately tackled by classical kinetic rate laws, but not the incongruent chalk dissolution. An apparent kinetic rate has therefore been fitted on field data by inverse modelling: 1.5×10(-5) mol(chalk)L (-1) water year (-1). Sensitivity analysis indicates that the CO(2) partial pressure of the unsaturated zone is a critical parameter for modelling the baseline chemistry over the whole chalk aquifer. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Modified stress intensity factor as a crack growth parameter applicable under large scale yielding conditions

    International Nuclear Information System (INIS)

    Yasuoka, Tetsuo; Mizutani, Yoshihiro; Todoroki, Akira

    2014-01-01

    High-temperature water stress corrosion cracking has high tensile stress sensitivity, and its growth rate has been evaluated using the stress intensity factor, which is a linear fracture mechanics parameter. Stress corrosion cracking mainly occurs and propagates around welded metals or heat-affected zones. These regions have complex residual stress distributions and yield strength distributions because of input heat effects. The authors previously reported that the stress intensity factor becomes inapplicable when steep residual stress distributions or yield strength distributions occur along the crack propagation path, because small-scale yielding conditions deviate around those distributions. Here, when the stress intensity factor is modified by considering these distributions, the modified stress intensity factor may be used for crack growth evaluation for large-scale yielding. The authors previously proposed a modified stress intensity factor incorporating the stress distribution or yield strength distribution in front of the crack using the rate of change of stress intensity factor and yield strength. However, the applicable range of modified stress intensity factor for large-scale yielding was not clarified. In this study, the range was analytically investigated by comparison with the J-integral solution. A three-point bending specimen with parallel surface crack was adopted as the analytical model and the stress intensity factor, modified stress intensity factor and equivalent stress intensity factor derived from the J-integral were calculated and compared under large-scale yielding conditions. The modified stress intensity was closer to the equivalent stress intensity factor when compared with the stress intensity factor. If deviation from the J-integral solution is acceptable up to 2%, the modified stress intensity factor is applicable up to 30% of the J-integral limit, while the stress intensity factor is applicable up to 10%. These results showed that

  7. Blood pressure reactivity to mental stress is attenuated following resistance exercise in older hypertensive women.

    Science.gov (United States)

    Gauche, Rafael; Lima, Ricardo M; Myers, Jonathan; Gadelha, André B; Neri, Silvia Gr; Forjaz, Claudia Lm; Vianna, Lauro C

    2017-01-01

    This study aimed to investigate the effects of resistance exercise (RE) on autonomic control and blood pressure (BP) reactivity during mental stress (MS) in treated older hypertensive women. Ten older hypertensive women (age =71.1±5.5 years; body mass index =24.2±3.9; mean BP [MBP] =85.4±3.5) underwent a protocol consisting of BP and heart rate variability (HRV) output assessments at baseline and during MS, and these measurements were taken before and 60 minutes after two bouts of RE (traditional and circuit). MS was induced through a computerized 3-minute Stroop color-word test before and 1 hour after each exercise session; BP was measured every minute during MS, and HRV was monitored as a measure of cardiac autonomic control. A significant effect of time on systolic BP (Δpre =17.4±12.8 versus Δpost =12.5±9.6; P =0.01), diastolic BP (Δpre =13.7±7.1 versus Δpost =8.8±4.5; P =0.01), and MBP (Δpre =14.0±7.7 versus Δpost =9.3±5.4; P <0.01) after RE was observed, with no differences between the two sessions. In addition, a significant effect of time on log-normalized low-frequency component of HRV (ms2; 5.3±0.8 pre-exercise MS versus 4.8±1.0 baseline value; P =0.023) was also observed, showing a significant change from baseline to MS before RE, but not after RE sessions. These results may be related to a lessened RE-mediated cardiac sympathetic activity during MS. RE is an effective tool to reduce BP reactivity to MS, which could therefore be associated with an acute reduction in cardiovascular risk. This result presents relevant clinical implications, combining previous evidence that recommends this exercise modality as an important component of an exercise program designed for the older and hypertensive subjects.

  8. Mild effects of gestational stress and social reactivity on the onset of mother-young interactions and bonding in sheep.

    Science.gov (United States)

    Coulon, Marjorie; Lévy, Frédéric; Ravel, Christine; Nowak, Raymond; Boissy, Alain

    2014-12-01

    Consequences of prenatal stress on mother-young relationships are well-documented in altricial mammals but less so in precocial mammals. In this study, we investigated the effects of unpredictable aversive events on maternal behavior and mutual mother-young recognition in pregnant ewes while accounting for modulatory effects of ewe reactivity. From a population of 120 Romane-breed ewes, we selected 20 high-responsive (HR) and 20 low-responsive (LR) ewes according to pre-mating reactivity assessed in isolation tests. Over the final third of pregnancy, 10 HR ewes and 10 LR ewes were exposed daily to various aversive events such as social isolation, mixing and transport (stressed ewes), while the other 20 ewes were not exposed to aversive events (control ewes). Although the treatment induced chronic stress, physiologically confirmed by an increase in salivary cortisol following transport and sham shearing, maternal behavior of stressed ewes observed during the first 30 min postpartum and in the selectivity test 1 h 30 min later did not differ from controls. However, in a maternal motivation test performed 48 h postpartum, stressed ewes vocalized less than controls when separated from their lambs, and walked less readily past an unknown object to reach their lambs. Lambs of stressed ewes spent more time near their dam in a preference test performed 15 h after birth compared to control-ewe lambs. HR ewes spent more time grooming their lambs than LR ewes. We posit that domestication could have selected animals displaying robust expression of maternal behavior related to social reactivity and producing offspring that are better adapted to challenging situations.

  9. Hair cortisol concentrations and cortisol stress reactivity predict PTSD symptom increase after trauma exposure during military deployment.

    Science.gov (United States)

    Steudte-Schmiedgen, Susann; Stalder, Tobias; Schönfeld, Sabine; Wittchen, Hans-Ulrich; Trautmann, Sebastian; Alexander, Nina; Miller, Robert; Kirschbaum, Clemens

    2015-09-01

    Previous evidence on endocrine risk markers for posttraumatic stress disorder (PTSD) has been inconclusive. Here, we report results of the first prospective study to investigate whether long-term hair cortisol levels and experimentally-induced cortisol stress reactivity are predictive of the development of PTSD symptomatology in response to trauma during military deployment. Male soldiers were examined before deployment to Afghanistan and at a 12-month post-deployment follow-up using dimensional measures for psychopathological symptoms. The predictive value of baseline (i) hair cortisol concentrations (HCC, N=90) and (ii) salivary cortisol stress reactivity (measured by the Trier Social Stress Test, N=80) for the development of PTSD symptomatology after being exposed to new-onset traumatic events was analyzed. Baseline cortisol activity significantly predicted PTSD symptom change from baseline to follow-up upon trauma exposure. Specifically, our results consistently revealed that lower HCC and lower cortisol stress reactivity were predictive of a greater increase in PTSD symptomatology in soldiers who had experienced new-onset traumatic events (explaining 5% and 10.3% of variance, respectively). Longitudinal analyses revealed an increase in HCC from baseline to follow-up and a trend for a negative relationship between HCC changes and the number of new-onset traumatic events. Additional pre-deployment analyses revealed that trauma history was reflected in lower HCC (at trend level) and that HCC were negatively related to stressful load. Our data indicate that attenuated cortisol secretion is a risk marker for subsequent development of PTSD symptomatology upon trauma exposure. Future studies are needed to confirm our findings in other samples. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Volume 1, Bench-scale testing and analysis

    Energy Technology Data Exchange (ETDEWEB)

    Jha, M.C.; Berggren, M.H.

    1989-05-02

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  11. Cross-cultural validity of the masculine and Feminine Gender Role Stress scales

    NARCIS (Netherlands)

    van Well, S; Kolk, AM; Arrindell, WA

    The objective was to examine the usefulness of Dutch versions of the Masculine Gender Role Stress (MGRS; Eisler & Skidmore, 1987) Scale and the Feminine Gender Role Stress (Gillespie & Eisler, 1992) Scale in The Netherlands. Undergraduate students (N = 2,239) completed both gender role stress

  12. Blood pressure reactivity to mental stress is attenuated following resistance exercise in older hypertensive women

    Directory of Open Access Journals (Sweden)

    Gauche R

    2017-05-01

    Full Text Available Rafael Gauche,1 Ricardo M Lima,1,2 Jonathan Myers,2 André B Gadelha,1 Silvia GR Neri,1 Claudia LM Forjaz,3 Lauro C Vianna1 1Faculty of Physical Education, University of Brasília, Brasília, Brazil; 2Cardiology Division, Veterans Affairs Palo Alto Health Care System and Stanford University, Palo Alto, CA, USA; 3School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil Purpose: This study aimed to investigate the effects of resistance exercise (RE on autonomic control and blood pressure (BP reactivity during mental stress (MS in treated older hypertensive women. Methods: Ten older hypertensive women (age =71.1±5.5 years; body mass index =24.2±3.9; mean BP [MBP] =85.4±3.5 underwent a protocol consisting of BP and heart rate variability (HRV output assessments at baseline and during MS, and these measurements were taken before and 60 minutes after two bouts of RE (traditional and circuit. MS was induced through a computerized 3-minute Stroop color–word test before and 1 hour after each exercise session; BP was measured every minute during MS, and HRV was monitored as a measure of cardiac autonomic control. Results: A significant effect of time on systolic BP (∆pre =17.4±12.8 versus ∆post =12.5±9.6; P=0.01, diastolic BP (∆pre =13.7±7.1 versus ∆post =8.8±4.5; P=0.01, and MBP (∆pre =14.0±7.7 versus ∆post =9.3±5.4; P<0.01 after RE was observed, with no differences between the two sessions. In addition, a significant effect of time on log-normalized low-frequency component of HRV (ms2; 5.3±0.8 pre-exercise MS versus 4.8±1.0 baseline value; P=0.023 was also observed, showing a significant change from baseline to MS before RE, but not after RE sessions. These results may be related to a lessened RE-mediated cardiac sympathetic activity during MS. Conclusion: RE is an effective tool to reduce BP reactivity to MS, which could therefore be associated with an acute reduction in cardiovascular risk. This

  13. Cardiovascular and cortisol reactivity and habituation to a virtual reality version of the Trier Social Stress Test: a pilot study

    DEFF Research Database (Denmark)

    Jönsson, Peter; Wallergård, Mattias; Osterberg, Kai

    2010-01-01

    reactivity and habituation to repeated stress provocations using a virtual reality (VR) version of TSST. The VR system was a CAVE™ system with three rear projected walls (4 m×3 m), and one floor projection. The system also included a head tracking system and passive stereoscopy. The virtual audience...... studies using the real-life TSST. If these results can be replicated with larger samples, VR technology may be used as a simple and standardized tool for social stress induction in experimental settings....

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

    Science.gov (United States)

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

    2017-11-01

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

  15. Effects of Metformin on Tissue Oxidative and Dicarbonyl Stress in Transgenic Spontaneously Hypertensive Rats Expressing Human C-Reactive Protein

    Czech Academy of Sciences Publication Activity Database

    Malínská, H.; Oliyarnyk, O.; Škop, V.; Šilhavý, Jan; Landa, Vladimír; Zídek, Václav; Mlejnek, Petr; Šimáková, Miroslava; Strnad, Hynek; Kazdová, L.; Pravenec, Michal

    2016-01-01

    Roč. 11, č. 3 (2016), e0150924 E-ISSN 1932-6203 R&D Projects: GA MŠk(CZ) LL1204; GA MZd(CZ) NT14325 Institutional support: RVO:67985823 ; RVO:68378050 Keywords : inflammation * spontaneously hypertensive rat * transgenic * C-reactive protein * dicarbonyl stress * metformin Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition Impact factor: 2.806, year: 2016

  16. Emotional Reactivity in Posttraumatic Stress Disorder: Behavioural and Neurobiological Correlates of Underlying Mechanisms and the Role of Emotional Memory Modification

    OpenAIRE

    Thome, Janine

    2017-01-01

    The symptom pattern of posttraumatic stress disorder (PTSD) comprises four clusters: “involuntary distressing memories”, “persistent avoidance of stimuli related to the traumatic event”, “negative alterations in cognition and mood”, and “in arousal and reactivity” (DSM 5, American Psychological Association). Increasing evidence points towards enhanced emotional reactivity as an underlying mechanism of the latter mentioned symptom pattern in individuals with PTSD. From a process oriented persp...

  17. Reactive Stresses in Ni49Fe18Ga27Co6 Shape-Memory-Alloy Single Crystals

    Science.gov (United States)

    Averkin, A. I.; Krymov, V. M.; Guzilova, L. I.; Timashov, R. B.; Soldatov, A. V.; Nikolaev, V. I.

    2018-03-01

    The reactive stresses induced in Ni49Fe18Ga27Co6-alloy single crystals during martensitic transformations with a limited possibility of shape-memory-strain recovery have been experimentally studied. The data on these crystals are compared with the results obtained previously for Cu-Al-Ni, Ni-Ti, and Ni‒Fe-Ga crystals. The potential of application of the Ni49Fe18Ga27Co6 single crystals in designing drives and power motors is demonstrated.

  18. The Depression Anxiety Stress Scales-21 (DASS-21): further examination of dimensions, scale reliability, and correlates.

    Science.gov (United States)

    Osman, Augustine; Wong, Jane L; Bagge, Courtney L; Freedenthal, Stacey; Gutierrez, Peter M; Lozano, Gregorio

    2012-12-01

    We conducted two studies to examine the dimensions, internal consistency reliability estimates, and potential correlates of the Depression Anxiety Stress Scales-21 (DASS-21; Lovibond & Lovibond, 1995). Participants in Study 1 included 887 undergraduate students (363 men and 524 women, aged 18 to 35 years; mean [M] age = 19.46, standard deviation [SD] = 2.17) recruited from two public universities to assess the specificity of the individual DASS-21 items and to evaluate estimates of internal consistency reliability. Participants in a follow-up study (Study 2) included 410 students (168 men and 242 women, aged 18 to 47 years; M age = 19.65, SD = 2.88) recruited from the same universities to further assess factorial validity and to evaluate potential correlates of the original DASS-21 total and scale scores. Item bifactor and confirmatory factor analyses revealed that a general factor accounted for the greatest proportion of common variance in the DASS-21 item scores (Study 1). In Study 2, the fit statistics showed good fit for the bifactor model. In addition, the DASS-21 total scale score correlated more highly with scores on a measure of mixed depression and anxiety than with scores on the proposed specific scales of depression or anxiety. Coefficient omega estimates for the DASS-21 scale scores were good. Further investigations of the bifactor structure and psychometric properties of the DASS-21, specifically its incremental and discriminant validity, using known clinical groups are needed. © 2012 Wiley Periodicals, Inc.

  19. Longevity of animals under reactive oxygen species stress and disease susceptibility due to global warming

    Science.gov (United States)

    Paital, Biswaranjan; Panda, Sumana Kumari; Hati, Akshaya Kumar; Mohanty, Bobllina; Mohapatra, Manoj Kumar; Kanungo, Shyama; Chainy, Gagan Bihari Nityananda

    2016-01-01

    The world is projected to experience an approximate doubling of atmospheric CO2 concentration in the next decades. Rise in atmospheric CO2 level as one of the most important reasons is expected to contribute to raise the mean global temperature 1.4 °C-5.8 °C by that time. A survey from 128 countries speculates that global warming is primarily due to increase in atmospheric CO2 level that is produced mainly by anthropogenic activities. Exposure of animals to high environmental temperatures is mostly accompanied by unwanted acceleration of certain biochemical pathways in their cells. One of such examples is augmentation in generation of reactive oxygen species (ROS) and subsequent increase in oxidation of lipids, proteins and nucleic acids by ROS. Increase in oxidation of biomolecules leads to a state called as oxidative stress (OS). Finally, the increase in OS condition induces abnormality in physiology of animals under elevated temperature. Exposure of animals to rise in habitat temperature is found to boost the metabolism of animals and a very strong and positive correlation exists between metabolism and levels of ROS and OS. Continuous induction of OS is negatively correlated with survivability and longevity and positively correlated with ageing in animals. Thus, it can be predicted that continuous exposure of animals to acute or gradual rise in habitat temperature due to global warming may induce OS, reduced survivability and longevity in animals in general and poikilotherms in particular. A positive correlation between metabolism and temperature in general and altered O2 consumption at elevated temperature in particular could also increase the risk of experiencing OS in homeotherms. Effects of global warming on longevity of animals through increased risk of protein misfolding and disease susceptibility due to OS as the cause or effects or both also cannot be ignored. Therefore, understanding the physiological impacts of global warming in relation to

  20. Oxidative stress/reactive metabolite gene expression signature in rat liver detects idiosyncratic hepatotoxicants

    Energy Technology Data Exchange (ETDEWEB)

    Leone, Angelique; Nie, Alex; Brandon Parker, J.; Sawant, Sharmilee; Piechta, Leigh-Anne; Kelley, Michael F., E-mail: mkelley2@its.jnj.com; Mark Kao, L.; Jim Proctor, S.; Verheyen, Geert; Johnson, Mark D.; Lord, Peter G.; McMillian, Michael K.

    2014-03-15

    Previously we reported a gene expression signature in rat liver for detecting a specific type of oxidative stress (OS) related to reactive metabolites (RM). High doses of the drugs disulfiram, ethinyl estradiol and nimesulide were used with another dozen paradigm OS/RM compounds, and three other drugs flutamide, phenacetin and sulindac were identified by this signature. In a second study, antiepileptic drugs were compared for covalent binding and their effects on OS/RM; felbamate, carbamazepine, and phenobarbital produced robust OS/RM gene expression. In the present study, liver RNA samples from drug-treated rats from more recent experiments were examined for statistical fit to the OS/RM signature. Of all 97 drugs examined, in addition to the nine drugs noted above, 19 more were identified as OS/RM-producing compounds—chlorpromazine, clozapine, cyproterone acetate, dantrolene, dipyridamole, glibenclamide, isoniazid, ketoconazole, methapyrilene, naltrexone, nifedipine, sulfamethoxazole, tamoxifen, coumarin, ritonavir, amitriptyline, valproic acid, enalapril, and chloramphenicol. Importantly, all of the OS/RM drugs listed above have been linked to idiosyncratic hepatotoxicity, excepting chloramphenicol, which does not have a package label for hepatotoxicity, but does have a black box warning for idiosyncratic bone marrow suppression. Most of these drugs are not acutely toxic in the rat. The OS/RM signature should be useful to avoid idiosyncratic hepatotoxicity of drug candidates. - Highlights: • 28 of 97 drugs gave a positive OS/RM gene expression signature in rat liver. • The specificity of the signature for human idiosyncratic hepatotoxicants was 98%. • The sensitivity of the signature for human idiosyncratic hepatotoxicants was 75%. • The signature can help eliminate hepatotoxicants from drug development.

  1. Longevity of animals under reactive oxygen species stress and disease susceptibility due to global warming.

    Science.gov (United States)

    Paital, Biswaranjan; Panda, Sumana Kumari; Hati, Akshaya Kumar; Mohanty, Bobllina; Mohapatra, Manoj Kumar; Kanungo, Shyama; Chainy, Gagan Bihari Nityananda

    2016-02-26

    The world is projected to experience an approximate doubling of atmospheric CO2 concentration in the next decades. Rise in atmospheric CO2 level as one of the most important reasons is expected to contribute to raise the mean global temperature 1.4 °C-5.8 °C by that time. A survey from 128 countries speculates that global warming is primarily due to increase in atmospheric CO2 level that is produced mainly by anthropogenic activities. Exposure of animals to high environmental temperatures is mostly accompanied by unwanted acceleration of certain biochemical pathways in their cells. One of such examples is augmentation in generation of reactive oxygen species (ROS) and subsequent increase in oxidation of lipids, proteins and nucleic acids by ROS. Increase in oxidation of biomolecules leads to a state called as oxidative stress (OS). Finally, the increase in OS condition induces abnormality in physiology of animals under elevated temperature. Exposure of animals to rise in habitat temperature is found to boost the metabolism of animals and a very strong and positive correlation exists between metabolism and levels of ROS and OS. Continuous induction of OS is negatively correlated with survivability and longevity and positively correlated with ageing in animals. Thus, it can be predicted that continuous exposure of animals to acute or gradual rise in habitat temperature due to global warming may induce OS, reduced survivability and longevity in animals in general and poikilotherms in particular. A positive correlation between metabolism and temperature in general and altered O2 consumption at elevated temperature in particular could also increase the risk of experiencing OS in homeotherms. Effects of global warming on longevity of animals through increased risk of protein misfolding and disease susceptibility due to OS as the cause or effects or both also cannot be ignored. Therefore, understanding the physiological impacts of global warming in relation to

  2. Association of BDNF Val66Met polymorphism with HPA and SAM axis reactivity to psychological and physical stress

    Directory of Open Access Journals (Sweden)

    Tsuru J

    2014-11-01

    Full Text Available Jusen Tsuru,1 Yoshihiro Tanaka,1 Yoshinobu Ishitobi,1 Yoshihiro Maruyama,1 Ayako Inoue,1 Aimi Kawano,1 Rie Ikeda,1 Tomoko Ando,1 Harumi Oshita,2 Saeko Aizawa,1 Koji Masuda,1 Haruka Higuma,1 Masayuki Kanehisa,1 Taiga Ninomiya,1 Jotaro Akiyoshi1 1Department of Neuropsychiatry, 2Department of Applied Linguistics, Faculty of Medicine, Oita University, Oita, Japan Background: Decreased expression of brain-derived neurotrophic factor (BDNF is implicated in enhanced stress responses. The BDNF Val66Met polymorphism is associated with psychological changes; for example, carriers of the Met allele exhibit increased harm avoidance as well as a higher prevalence of depression and anxiety disorder.Methods: To analyze the effects of BDNF Val66Met on stress responses, we tested 226 university students (88 women and 138 men using a social stress procedure (Trier Social Stress Test [TSST] and an electrical stimulation stress test. Stress indices were derived from repeated measurements of salivary α-amylase, salivary cortisol, heart rate, and psychological testing during the stress tests. All subjects were genotyped for the Val66Met polymorphism (G196A.Results: A significant three-way interaction (time [3 levels] × BDNF [Val/Val, Val/Met, Met/Met]; P<0.05 was demonstrated that revealed different salivary cortisol responses in the TSST but not in electrical stimulation. Met/Met women had stronger cortisol responses than Val/Met and Val/Val individuals in the TSST. Met/Met men exhibited stronger salivary cortisol responses than Val/Met and Val/Val individuals in the TSST.Conclusion: These results indicate that a common, functionally significant polymorphism in BDNF had different effects on hypothalamic–pituitary–adrenocortical axis reactivity but not on sympathetic adrenomedullary reactivity in TSST and electrical stimulation tests. Keywords: stress, brain-derived neurotrophic factor, cortisol, saliva

  3. Towards modeling intergranular stress corrosion cracks on grain size scales

    International Nuclear Information System (INIS)

    Simonovski, Igor; Cizelj, Leon

    2012-01-01

    Highlights: ► Simulating the onset and propagation of intergranular cracking. ► Model based on the as-measured geometry and crystallographic orientations. ► Feasibility, performance of the proposed computational approach demonstrated. - Abstract: Development of advanced models at the grain size scales has so far been mostly limited to simulated geometry structures such as for example 3D Voronoi tessellations. The difficulty came from a lack of non-destructive techniques for measuring the microstructures. In this work a novel grain-size scale approach for modelling intergranular stress corrosion cracking based on as-measured 3D grain structure of a 400 μm stainless steel wire is presented. Grain topologies and crystallographic orientations are obtained using a diffraction contrast tomography, reconstructed within a detailed finite element model and coupled with advanced constitutive models for grains and grain boundaries. The wire is composed of 362 grains and over 1600 grain boundaries. Grain boundary damage initialization and early development is then explored for a number of cases, ranging from isotropic elasticity up to crystal plasticity constitutive laws for the bulk grain material. In all cases the grain boundaries are modeled using the cohesive zone approach. The feasibility of the approach is explored.

  4. Reactivity of the calcite–water-interface, from molecular scale processes to geochemical engineering

    International Nuclear Information System (INIS)

    Heberling, Frank; Bosbach, Dirk; Eckhardt, Jörg-Detlef; Fischer, Uwe; Glowacky, Jens; Haist, Michael; Kramar, Utz; Loos, Steffen; Müller, Harald S.; Neumann, Thomas; Pust, Christopher; Schäfer, Thorsten; Stelling, Jan

    2014-01-01

    Highlights: • The current state of some aspects of calcite–water-interface chemistry is reviewed. • The interface structure is characterized at a molecular scale. • Experimental and theoretical studies on contaminant sorption at calcite are presented. • The influence of phosphonates on calcite growth is investigated. • The effect of limestone on the workability of cement suspensions is addressed. - Abstract: Surface reactions on calcite play an important role in geochemical and environmental systems, as well as many areas of industry. In this review, we present investigations of calcite that were performed in the frame of the joint research project “RECAWA” (reactivity of calcite–water-interfaces: molecular process understanding for technical applications). As indicated by the project title, work within the project comprised a large range of length scales. The molecular scale structure of the calcite (1 0 4)–water-interface is refined based on surface diffraction data. Structural details are related to surface charging phenomena, and a simplified basic stern surface complexation model is proposed. As an example for trace metal interactions with calcite surfaces we review and present new spectroscopic and macroscopic experimental results on Selenium interactions with calcite. Results demonstrate that selenate (SeO 4 2− ) shows no significant interaction with calcite at our experimental conditions, while selenite (SeO 3 2− ) adsorbs at the calcite surface and can be incorporated into the calcite structure. Atomistic calculations are used to assess the thermodynamics of sulfate (SO 4 2− ), selenate (SeO 4 2− ), and selenite (SeO 3 2− ) partitioning in calcite and aragonite. The results show that incorporation of these oxo-anions into the calcite structure is so highly endothermic that incorporation is practically impossible at bulk equilibrium and standard conditions. This indicates that entrapment processes are involved when

  5. A literature review of the application of the Geriatric Depression Scale, Depression Anxiety Stress Scales and Post-traumatic Stress Disorder Checklist to community nursing cohorts.

    Science.gov (United States)

    Allen, Jacqui; Annells, Merilyn

    2009-04-01

    To explore through literature review the appropriateness of three common tools for use by community nurses to screen war veteran and war widow(er) clients for depression, anxiety and post-traumatic stress disorder. War veterans and, to a lesser extent, war widow(er)s, are prone to mental health challenges, especially depression, anxiety and post-traumatic stress disorder. Community nurses do not accurately identify such people with depression and related disorders although they are well positioned to do so. The use of valid and reliable self-report tools is one method of improving nurses' identification of people with actual or potential mental health difficulties for referral to a general practitioner or mental health practitioner for diagnostic assessment and treatment. The Geriatric Depression Scale, Depression Anxiety Stress Scales and Post-traumatic Stress Disorder Checklist are frequently recommended for mental health screening but the appropriateness of using the tools for screening war veteran and war widow(er) community nursing clients who are often aged and have functional impairment, is unknown. Systematic review. Current literature informs that the Geriatric Depression Scale accurately predicts a diagnosis of depression in community nursing cohorts. The three Depression Anxiety Stress Scales subscales of depression, anxiety and stress are valid; however, no studies were identified that compared the performance of the Depression Anxiety Stress Scales in predicting diagnoses of depression or anxiety. The Post-traumatic Stress Disorder Checklist predicts post-traumatic stress disorder in community cohorts although no studies meeting the selection criteria included male participants. This review provides recommendations for the use of the Geriatric Depression Scale, Depression Anxiety Stress Scales and The Post-traumatic Stress Disorder Checklist based on examination of the published evidence for the application of these screening tools in samples

  6. Regulation of reactive oxygen and nitrogen species by salicylic acid in rice plants under salinity stress conditions

    Science.gov (United States)

    Mun, Bong-Gyu; Khan, Abdul Latif; Waqas, Muhammad; Kim, Hyun-Ho; Shahzad, Raheem; Imran, Muhammad

    2018-01-01

    This study investigated the regulatory role of exogenous salicylic acid (SA) in rice and its effects on toxic reactive oxygen and nitrogen species during short-term salinity stress. SA application (0.5 and 1.0 mM) during salinity-induced stress (100 mM NaCl) resulted in significantly longer shoot length and higher chlorophyll and biomass accumulation than with salinity stress alone. NaCl-induced reactive oxygen species production led to increased levels of lipid peroxidation in rice plants, which were significantly reduced following SA application. A similar finding was observed for superoxide dismutase; however, catalase (CAT) and ascorbate peroxidase (APX) were significantly reduced in rice plants treated with SA and NaCl alone and in combination. The relative mRNA expression of OsCATA and OsAPX1 was lower in rice plants during SA stress. Regarding nitrogenous species, S-nitrosothiol (SNO) was significantly reduced initially (one day after treatment [DAT]) but then increased in plants subjected to single or combined stress conditions. Genes related to SNO biosynthesis, S-nitrosoglutathione reductase (GSNOR1), NO synthase-like activity (NOA), and nitrite reductase (NIR) were also assessed. The mRNA expression of GSNOR1 was increased relative to that of the control, whereas OsNOA was expressed at higher levels in plants treated with SA and NaCl alone relative to the control. The mRNA expression of OsNR was decreased in plants subjected to single or combination treatment, except at 2 DAT, compared to the control. In conclusion, the current findings suggest that SA can regulate the generation of NaCl-induced oxygen and nitrogen reactive species in rice plants. PMID:29558477

  7. The impact of cortisol reactivity to acute stress on memory: sex differences in middle-aged people.

    Science.gov (United States)

    Almela, Mercedes; Hidalgo, Vanesa; Villada, Carolina; Espín, Laura; Gómez-Amor, Jesús; Salvador, Alicia

    2011-03-01

    Stress has been identified as a main factor involved in the cognitive changes that occur during the aging process. This study investigated sex differences in the relationship between the magnitude of the acute stress-induced salivary cortisol response and memory performance among middle-aged people. To this end, 16 men and 16 women (aged 54-72 years) were exposed to the Trier Social Stress Test and a control condition in a crossover design. Afterwards their memory performance was measured using a standardized memory test (Rey's Auditory Verbal Learning Test). Only among women, there was an acute impact of stress on memory performance and a significant relationship between a higher cortisol response to the stressor and poorer memory performance in both the stress and control conditions. Additionally, a poorer memory performance was related to earlier timing of sexual maturation (age at menarche), which was also marginally related to higher cortisol reactivity to stress. These results confirm that sex is a critical factor in the relationship between cortisol and poor memory performance. Furthermore, the findings emphasize a strong link between the individual cortisol response to stress and memory functioning among postmenopausal women.

  8. SKA2 Methylation is Involved in Cortisol Stress Reactivity and Predicts the Development of Post-Traumatic Stress Disorder (PTSD) After Military Deployment.

    Science.gov (United States)

    Boks, Marco P; Rutten, Bart P F; Geuze, Elbert; Houtepen, Lotte C; Vermetten, Eric; Kaminsky, Zachary; Vinkers, Christiaan H

    2016-04-01

    Genomic variation in the SKA2 gene has recently been identified as a promising suicide biomarker. In light of its role in glucocorticoid receptor transactivation, we investigated whether SKA2 DNA methylation influences cortisol stress reactivity and is involved in the development of post-traumatic stress disorder (PTSD). Increased SKA2 methylation was significantly associated with lower cortisol stress reactivity in 85 healthy individuals exposed to the Trier Social Stress Test (B=-173.40, t=-2.324, p-value=0.023). Next, we observed that longitudinal decreases in SKA2 methylation after deployment were associated with the emergence of post-deployment PTSD symptoms in a Dutch military cohort (N=93; B=-0.054, t=-3.706, p-value=3.66 × 10(-4)). In contrast, exposure to traumatic stress during deployment by itself resulted in longitudinal increases in SKA2 methylation (B=0.037, t=4.173, p-value=6.98 × 10(-5)). Using pre-deployment SKA2 methylation levels and childhood trauma exposure, we found that the previously published suicide prediction rule significantly predicted post-deployment PTSD symptoms (AUC=0.66, 95% CI: 0.53-0.79) with an optimal sensitivity of 0.81 and specificity of 0.91. Permutation analysis using random methylation loci supported these findings. Together, these data establish the importance of SKA2 for cortisol stress responsivity and the development of PTSD and provide further evidence that SKA2 is a promising biomarker for stress-related disorders including PTSD.

  9. Temperature and Stresses Estimation in Reactivity Control Rods for CAREM-25 Reactor

    International Nuclear Information System (INIS)

    Markiewicz, Mario; Estevez, Esteban

    2000-01-01

    The reactivity control rods are a critical component regarding safety.Its correct operation when required must be ensured.For this purpose, this component must maintain its operating capacity during all its residence time and under any foreseen operation condition.To evaluate the behaviour of reactivity control rods, it is necessary to analyse the demands they are exposed to, determining from the mechanical point of view, the residence time in the reactor core.In this report, using analytical calculations, the parameters affecting the performance of the reactivity control rods are analysed, with the objective of determine from the mechanical point of view, its behaviour and residence time

  10. Rap1 signaling is required for suppression of Ras-generated reactive oxygen species and protection against oxidative stress in T lymphocytes

    NARCIS (Netherlands)

    Remans, Philip H. J.; Gringhuis, Sonja I.; van Laar, Jacob M.; Sanders, Marjolein E.; Papendrecht-van der Voort, Ellen A. M.; Zwartkruis, Fried J. T.; Levarht, E. W. Nivine; Rosas, Marcela; Coffer, Paul J.; Breedveld, Ferdinand C.; Bos, Johannes L.; Tak, Paul P.; Verweij, Cornelis L.; Reedquist, Kris A.

    2004-01-01

    Transient production of reactive oxygen species (ROS) plays an important role in optimizing transcriptional and proliferative responses to TCR signaling in T lymphocytes. Conversely, chronic oxidative stress leads to decreased proliferative responses and enhanced transcription of inflammatory gene

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

    National Research Council Canada - National Science Library

    Howell, Robert H

    1996-01-01

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

  12. Better cognitive control of emotional information is associated with reduced pro-inflammatory cytokine reactivity to emotional stress.

    Science.gov (United States)

    Shields, Grant S; Kuchenbecker, Shari Young; Pressman, Sarah D; Sumida, Ken D; Slavich, George M

    2016-01-01

    Stress is strongly associated with several mental and physical health problems that involve inflammation, including asthma, cardiovascular disease, certain types of cancer, and depression. It has been hypothesized that better cognitive control of emotional information may lead to reduced inflammatory reactivity to stress and thus better health, but to date no studies have examined whether differences in cognitive control predict pro-inflammatory cytokine responses to stress. To address this issue, we conducted a laboratory-based experimental study in which we randomly assigned healthy young-adult females to either an acute emotional stress (emotionally evocative video) or no-stress (control video) condition. Salivary levels of the key pro-inflammatory cytokines IL-1β, IL-6, and IL-8 were measured before and after the experimental manipulation, and following the last cytokine sample, we assessed participants' cognitive control of emotional information using an emotional Stroop task. We also assessed participants' cortisol levels before and after the manipulation to verify that documented effects were specific to cytokines and not simply due to increased nonwater salivary output. As hypothesized, the emotional stressor triggered significant increases in IL-1β, IL-6, and IL-8. Moreover, even in fully adjusted models, better cognitive control following the emotional (but not control) video predicted less pronounced cytokine responses to that stressor. In contrast, no effects were observed for cortisol. These data thus indicate that better cognitive control specifically following an emotional stressor is uniquely associated with less pronounced pro-inflammatory cytokine reactivity to such stress. These findings may therefore help explain why superior cognitive control portends better health over the lifespan.

  13. BDNF Val66Met polymorphism is associated with HPA axis reactivity to psychological stress characterized by genotype and gender interactions.

    Science.gov (United States)

    Shalev, Idan; Lerer, Elad; Israel, Salomon; Uzefovsky, Florina; Gritsenko, Inga; Mankuta, David; Ebstein, Richard P; Kaitz, Marsha

    2009-04-01

    A key protein in maintaining neuronal integrity throughout the life span is brain-derived neurotrophic factor (BDNF). The BDNF gene is characterized by a functional polymorphism, which has been associated with stress-related disorders such as anxiety-related syndromes and depression, prompting us to examine individual responses by Genotype and Sex to a standardized social stress paradigm. Gender differences in BDNFxstress responses were posited because estrogen induces synthesis of BDNF in several brain regions. 97 university students (51 females and 46 males) participated in a social stress procedure (Trier Social Stress Test, TSST). Indices of stress were derived from repeated measurement of cortisol, blood pressure, and heart rate during the TSST. All subjects were genotyped for the Val66Met polymorphism. Tests of within-subject effects showed a significant three-way interaction (SPSS GLM repeated measures: Time (eight levels)xBDNF (val/val, val/met)xSex: p=0.0002), which reflects gender differences in the pattern of cortisol rise and decline during the social challenge. In male subjects, val/val homozygotes showed a greater rise in salivary cortisol than val/met heterozygotes. In female subjects, there was a trend for the opposite response, which is significant when area under the curve increase (AUCi) was calculated for the val/val homozygotes to show the lowest rise. Overall, the same pattern of results was observed for blood pressure and heart rate. These results indicate that a common, functionally significant polymorphism in the BDNF gene modulates HPA axis reactivity and regulation during the TSST differently in men and women. Findings may be related to gender differences in reactivity and vulnerability to social stress.

  14. Monohalogenated acetamide-induced cellular stress and genotoxicity are related to electrophilic softness and thiol/thiolate reactivity.

    Science.gov (United States)

    Pals, Justin A; Wagner, Elizabeth D; Plewa, Michael J; Xia, Menghang; Attene-Ramos, Matias S

    2017-08-01

    Haloacetamides (HAMs) are cytotoxic, genotoxic, and mutagenic byproducts of drinking water disinfection. They are soft electrophilic compounds that form covalent bonds with the free thiol/thiolate in cysteine residues through an S N 2 reaction mechanism. Toxicity of the monohalogenated HAMs (iodoacetamide, IAM; bromoacetamide, BAM; or chloroacetamide, CAM) varied depending on the halogen substituent. The aim of this research was to investigate how the halogen atom affects the reactivity and toxicological properties of HAMs, measured as induction of oxidative/electrophilic stress response and genotoxicity. Additionally, we wanted to determine how well in silico estimates of electrophilic softness matched thiol/thiolate reactivity and in vitro toxicological endpoints. Each of the HAMs significantly induced nuclear Rad51 accumulation and ARE signaling activity compared to a negative control. The rank order of effect was IAM>BAM>CAM for Rad51, and BAM≈IAM>CAM for ARE. In general, electrophilic softness and in chemico thiol/thiolate reactivity provided a qualitative indicator of toxicity, as the softer electrophiles IAM and BAM were more thiol/thiolate reactive and were more toxic than CAM. Copyright © 2017. Published by Elsevier B.V.

  15. Dark chocolate attenuates intracellular pro-inflammatory reactivity to acute psychosocial stress in men: A randomized controlled trial.

    Science.gov (United States)

    Kuebler, Ulrike; Arpagaus, Angela; Meister, Rebecca E; von Känel, Roland; Huber, Susanne; Ehlert, Ulrike; Wirtz, Petra H

    2016-10-01

    Flavanol-rich dark chocolate consumption relates to lower risk of cardiovascular mortality, but underlying mechanisms are elusive. We investigated the effect of acute dark chocolate consumption on inflammatory measures before and after stress. Healthy men, aged 20-50years, were randomly assigned to a single intake of either 50g of flavanol-rich dark chocolate (n=31) or 50g of optically identical flavanol-free placebo-chocolate (n=34). Two hours after chocolate intake, both groups underwent the 15-min Trier Social Stress Test. We measured DNA-binding-activity of the pro-inflammatory transcription factor NF-κB (NF-κB-BA) in peripheral blood mononuclear cells, as well as plasma and whole blood mRNA levels of the pro-inflammatory cytokines IL-1β and IL-6, and the anti-inflammatory cytokine IL-10, prior to chocolate intake as well as before and several times after stress. We also repeatedly measured the flavanol epicatechin and the stress hormones epinephrine and cortisol in plasma and saliva, respectively. Compared to the placebo-chocolate-group, the dark-chocolate-group revealed a marginal increase in IL-10 mRNA prior to stress (p=0.065), and a significantly blunted stress reactivity of NF-κB-BA, IL-1β mRNA, and IL-6 mRNA (p's⩽0.036) with higher epicatechin levels relating to lower pro-inflammatory stress reactivity (p's⩽0.033). Stress hormone changes to stress were controlled. None of the other measures showed a significant chocolate effect (p's⩾0.19). Our findings indicate that acute flavanol-rich dark chocolate exerts anti-inflammatory effects both by increasing mRNA expression of the anti-inflammatory cytokine IL-10 and by attenuating the intracellular pro-inflammatory stress response. This mechanism may add to beneficial effects of dark chocolate on cardiovascular health. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Reactive Oxygen Species Generation-Scavenging and Signaling during Plant-Arbuscular Mycorrhizal and Piriformospora indica Interaction under Stress Condition.

    Science.gov (United States)

    Nath, Manoj; Bhatt, Deepesh; Prasad, Ram; Gill, Sarvajeet S; Anjum, Naser A; Tuteja, Narendra

    2016-01-01

    A defined balance between the generation and scavenging of reactive oxygen species (ROS) is essential to utilize ROS as an adaptive defense response of plants under biotic and abiotic stress conditions. Moreover, ROS are not only a major determinant of stress response but also act as signaling molecule that regulates various cellular processes including plant-microbe interaction. In particular, rhizosphere constitutes the biologically dynamic zone for plant-microbe interactions which forms a mutual link leading to reciprocal signaling in both the partners. Among plant-microbe interactions, symbiotic associations of arbuscular mycorrhizal fungi (AMF) and arbuscular mycorrhizal-like fungus especially Piriformospora indica with plants are well known to improve plant growth by alleviating the stress-impacts and consequently enhance the plant fitness. AMF and P. indica colonization mainly enhances ROS-metabolism, maintains ROS-homeostasis, and thereby averts higher ROS-level accrued inhibition in plant cellular processes and plant growth and survival under stressful environments. This article summarizes the major outcomes of the recent reports on the ROS-generation, scavenging and signaling in biotic-abiotic stressed plants with AMF and P. indica colonization. Overall, a detailed exploration of ROS-signature kinetics during plant-AMF/ P. indica interaction can help in designing innovative strategies for improving plant health and productivity under stress conditions.

  17. Involvement of Reactive Oxygen Species and Mitochondrial Proteins in Biophoton Emission in Roots of Soybean Plants under Flooding Stress.

    Science.gov (United States)

    Kamal, Abu Hena Mostafa; Komatsu, Setsuko

    2015-05-01

    To understand the mechanism of biophoton emission, ROS and mitochondrial proteins were analyzed in soybean plants under flooding stress. Enzyme activity and biophoton emission were increased in the flooding stress samples when assayed in reaction mixes specific for antioxidant enzymes and reactive oxygen species; although the level of the hydroxyl radicals was increased at day 4 (2 days of flooding) compared to nonflooding at day 4, the emission of biophotons did not change. Mitochondria were isolated and purified from the roots of soybean plants grown under flooding stress by using a Percoll gradient, and proteins were analyzed by a gel-free proteomic technique. Out of the 98 mitochondrial proteins that significantly changed abundance under flooding stress, 47 increased and 51 decreased at day 4. The mitochondrial enzymes fumarase, glutathione-S-transferase, and aldehyde dehydrogenase increased at day 4 in protein abundance and enzyme activity. Enzyme activity and biophoton emission decreased at day 4 by the assay of lipoxygenase under stress. Aconitase, acyl CoA oxidase, succinate dehydrogenase, and NADH ubiquinone dehydrogenase were up-regulated at the transcription level. These results indicate that oxidation and peroxide scavenging might lead to biophoton emission and oxidative damage in the roots of soybean plants under flooding stress.

  18. Buoyancy limits on magnetic viscosity stress-law scalings in quasi stellar object accretion disk models

    International Nuclear Information System (INIS)

    Sakimoto, P.J.

    1985-01-01

    Quasi-Stellar Objects (QSOs) are apparently the excessively bright nuclei of distant galaxies. They are thought to be powered by accretion disks surrounding supermassive black holes: however, proof of this presumption is hampered by major uncertainties in the viscous stress necessary for accretion to occur. Models generally assume an and hoc stress law which scales the stress with the total pressure. Near the black hole, radiation pressure dominates gas pressure; scaling the stress with the radiation pressure results in disk models that are thermally unstable and optically thin. This dissertation shows that a radiation pressure scaling for the stress is not possible if the viscosity is due to turbulent magnetic Maxwell stresses. The argument is one of internal self-consistency. First, four model accretion disks that bound the reasonably expected ranges of viscous stress scalings and vertical structures are constructed. Magnetic flux tubes of various initial field strengths are then placed within these models, nd their buoyancy is modeled numerically. In disks using the radiation pressure stress law scaling, low opacities allow rapid heat flow into the flux tubes: the tubes are extremely buoyant, and magnetic fields strong enough to provide the required stress cannot be retained. If an alternative gas pressure scaling for the stress is assumed, then the disks are optically thick; flux tubes have corresponding lower buoyancy, and magnetic fields strong enough to provide the stress can be retained for dynamically significant time periods

  19. Chronic parenting stress and mood reactivity: The role of sleep quality.

    Science.gov (United States)

    da Estrela, Chelsea; Barker, Erin T; Lantagne, Sarah; Gouin, Jean-Philippe

    2018-04-01

    Sleep is a basic biological process supporting emotion regulation. The emotion regulation function of sleep may be particularly important in the context of chronic stress. To better understand how chronic stress and sleep interact to predict mood, 66 parents of children with autism completed daily diaries assessing parenting stress, negative mood, and sleep quality for 6 consecutive days. Hierarchical linear modelling revealed that daily negative mood was predicted by between-person differences in parenting stress and between-person differences in sleep efficiency. Further, between-person differences in sleep efficiency and within-person differences in sleep satisfaction moderated the impact of stress on mood. These data suggest that sleep disturbances may exacerbate the association between stress and mood in the context of chronic parenting stress. Further, high parenting stress appears to heighten the impact of transient sleep disturbances on mood. Copyright © 2017 John Wiley & Sons, Ltd.

  20. Emotional reactivity to a single inhalation of 35% carbon dioxide and its association with later symptoms of posttraumatic stress disorder and anxiety in soldiers deployed to Iraq.

    Science.gov (United States)

    Telch, Michael J; Rosenfield, David; Lee, Han-Joo; Pai, Anushka

    2012-11-01

    The identification of modifiable predeployment vulnerability factors that increase the risk of combat stress reactions among soldiers once deployed to a war zone offers significant potential for the prevention of posttraumatic stress disorder (PTSD) and other combat-related stress disorders. Adults with anxiety disorders display heightened emotional reactivity to a single inhalation of 35% carbon dioxide (CO(2)); however, data investigating prospective linkages between emotional reactivity to CO(2) and susceptibility to war-zone stress reactions are lacking. To investigate the association of soldiers' predeployment emotional reactivity to 35% CO(2) challenge with several indices of subsequent war-zone stress symptoms assessed monthly while deployed in Iraq. Prospective cohort study of 158 soldiers with no history of deployment to a war zone were recruited from the Texas Combat Stress Risk Study between April 2, 2007, and August 28, 2009. Multilevel regression models were used to investigate the association between emotional reactivity to 35% CO(2) challenge (assessed before deployment) and soldiers' reported symptoms of general anxiety/stress, PTSD, and depression while deployed to Iraq. Growth curves of PTSD, depression, and general anxiety/stress symptoms showed a significant curvilinear relationship during the 16-month deployment period. War-zone stressors reported in theater were associated with symptoms of general anxiety/stress, PTSD, and depression. Consistent with the prediction, soldiers' emotional reactivity to a single inhalation of 35% CO(2)-enriched air before deployment significantly potentiated the effects of war-zone stressors on the subsequent development of PTSD symptoms and general anxiety/stress symptoms but not on the development of depression, even after accounting for the effects of trait anxiety and the presence of past or current Axis I mental disorders. Soldiers' emotional reactivity to a 35% CO(2) challenge may serve as a vulnerability

  1. A WRKY gene from Tamarix hispida, ThWRKY4, mediates abiotic stress responses by modulating reactive oxygen species and expression of stress-responsive genes.

    Science.gov (United States)

    Zheng, Lei; Liu, Guifeng; Meng, Xiangnan; Liu, Yujia; Ji, Xiaoyu; Li, Yanbang; Nie, Xianguang; Wang, Yucheng

    2013-07-01

    WRKY transcription factors are involved in various biological processes, such as development, metabolism and responses to stress. However, their exact roles in abiotic stress tolerance are largely unknown. Here, we demonstrated a working model for the function of a WRKY gene (ThWRKY4) from Tamarix hispida in the stress response. ThWRKY4 is highly induced by abscisic acid (ABA), salt and drought in the early period of stress (stress for 3, 6, or 9 h), which can be regulated by ABF (ABRE binding factors) and Dof (DNA binding with one finger), and also can be crossregulated by other WRKYs and autoregulated as well. Overexpression of ThWRKY4 conferred tolerance to salt, oxidative and ABA treatment in transgenic plants. ThWRKY4 can improve the tolerance to salt and ABA treatment by improving activities of superoxide dismutase and peroxidase, decreasing levels of O2 (-) and H2O2, reducing electrolyte leakage, keeping the loss of chlorophyll, and protecting cells from death. Microarray analyses showed that overexpression of ThWRKY4 in Arabidopsis leads to 165 and 100 genes significantly up- and downregulated, respectively. Promoter scanning analysis revealed that ThWRKY4 regulates the gene expression via binding to W-box motifs present in their promoter regions. This study shows that ThWRKY4 functions as a transcription factor to positively modulate abiotic stress tolerances, and is involved in modulating reactive oxygen species.

  2. Reliability and preliminary evidence of validity of a Farsi version of the depression anxiety stress scales.

    Science.gov (United States)

    Bayani, Ali Asghar

    2010-08-01

    The internal consistency, test-retest reliability, and construct validity of the Farsi version of the Depression Anxiety Stress Scales were examined, with a sample of 306 undergraduate students (123 men, 183 women) ranging from 18 to 51 years of age (M age = 25.4, SD = 6.1). Participants completed the Satisfaction with Life Scale, Rosenberg Self-esteem Scale, and the Depression Anxiety Stress Scales. The findings confirmed the preliminary reliabilities and preliminary construct validity of the Farsi translation of the Depression Anxiety Stress Scales.

  3. Subgrid-scale stresses and scalar fluxes constructed by the multi-scale turnover Lagrangian map

    Science.gov (United States)

    AL-Bairmani, Sukaina; Li, Yi; Rosales, Carlos; Xie, Zheng-tong

    2017-04-01

    The multi-scale turnover Lagrangian map (MTLM) [C. Rosales and C. Meneveau, "Anomalous scaling and intermittency in three-dimensional synthetic turbulence," Phys. Rev. E 78, 016313 (2008)] uses nested multi-scale Lagrangian advection of fluid particles to distort a Gaussian velocity field and, as a result, generate non-Gaussian synthetic velocity fields. Passive scalar fields can be generated with the procedure when the fluid particles carry a scalar property [C. Rosales, "Synthetic three-dimensional turbulent passive scalar fields via the minimal Lagrangian map," Phys. Fluids 23, 075106 (2011)]. The synthetic fields have been shown to possess highly realistic statistics characterizing small scale intermittency, geometrical structures, and vortex dynamics. In this paper, we present a study of the synthetic fields using the filtering approach. This approach, which has not been pursued so far, provides insights on the potential applications of the synthetic fields in large eddy simulations and subgrid-scale (SGS) modelling. The MTLM method is first generalized to model scalar fields produced by an imposed linear mean profile. We then calculate the subgrid-scale stress, SGS scalar flux, SGS scalar variance, as well as related quantities from the synthetic fields. Comparison with direct numerical simulations (DNSs) shows that the synthetic fields reproduce the probability distributions of the SGS energy and scalar dissipation rather well. Related geometrical statistics also display close agreement with DNS results. The synthetic fields slightly under-estimate the mean SGS energy dissipation and slightly over-predict the mean SGS scalar variance dissipation. In general, the synthetic fields tend to slightly under-estimate the probability of large fluctuations for most quantities we have examined. Small scale anisotropy in the scalar field originated from the imposed mean gradient is captured. The sensitivity of the synthetic fields on the input spectra is assessed by

  4. Well-Being and Safety among Inpatient Psychiatric Staff: The Impact of Conflict, Assault, and Stress Reactivity

    Science.gov (United States)

    Kelly, Erin L.; Fenwick, Karissa; Brekke, John S.; Novaco, Raymond W.

    2015-01-01

    Psychiatric staff are faced with multiple forms of hostility, aggression, and assault at work, collectively referred to as workplace violence, which typically is activated by patients but can also come from coworkers and supervisors. Whether workplace violence adversely affects staff well-being may be related not only to its presence, but also to an individual’s stress reactivity. At a large public psychiatric hospital, an online survey was completed by 323 clinical care staff, of whom 69.5% had experienced physical assault in the previous 12 months. Staff well-being (depression, anger, and physical health) and staff safety concerns were adversely affected by conflicts with other staff members and by individual reactivity to social conflict and to assault. To improve staff well-being, in addition to safety protocols, interventions should target staff relationships, personal health maintenance practices, and individual coping skills for dealing with adverse workplace experiences. PMID:26377816

  5. Neuroendocrine stress reactivity of male C57BL/6N mice following chronic oral corticosterone exposure during adulthood or adolescence.

    Science.gov (United States)

    Shahanoor, Ziasmin; Sultana, Razia; Baker, Madelyn R; Romeo, Russell D

    2017-12-01

    Adolescence is associated with the maturation of the hypothalamic-pituitary-adrenal (HPA) axis, the major neuroendocrine axis mediating the hormonal stress response. Adolescence is also a period in development marked by a variety of stress-related vulnerabilities, including psychological and physiological dysfunctions. Many of these vulnerabilities are accompanied by a disrupted HPA axis. In adult mice, a model of disrupted HPA function has been developed using oral chronic corticosterone administration via the drinking water, which results in various physiological and neurobehavioral abnormalities, including changes in stress reactivity and anxiety-like behaviors. In an effort to further complement and extend this model, we tested the impact of HPA disruption in adolescent mice. We also examined whether this disruption led to different outcomes depending on whether the treatment happened during adolescence or adulthood. In the current set of experiments, we exposed adult (70days of age) or adolescent (30days of age) male C57BL/6N mice to 4 weeks of either 0 or 25μg/ml oral corticosterone via their drinking water. We measured body weight during treatment and plasma corticosterone levels and activation of the paraventricular nucleus (PVN), as indexed by FOS immunohistochemistry, before and after a 30min session of restraint stress. Our data indicate that adolescent animals exposed to chronic corticosterone showed weight loss during treatment, an effect not observed in adults. Further, we found stress failed to elevate plasma corticosterone levels in treated mice, regardless of whether exposure occurred in adulthood or adolescence. Despite this reduced hormonal responsiveness, we found significant neural activation in the PVN of both adult- and adolescent-treated mice, indicating a dissociation between stress-induced peripheral and central stress responses following chronic corticosterone exposure. Moreover, stress-induced neural activation in the PVN was unaffected

  6. Can reactivity to stress and family environment explain memory and executive function performance in early and middle childhood?

    Science.gov (United States)

    Piccolo, Luciane da Rosa; Salles, Jerusa Fumagalli de; Falceto, Olga Garcia; Fernandes, Carmen Luiza; Grassi-Oliveira, Rodrigo

    2016-01-01

    According to the literature, children's overall reactivity to stress is associated with their socioeconomic status and family environment. In turn, it has been shown that reactivity to stress is associated with cognitive performance. However, few studies have systematically tested these three constructs together. To investigate the relationship between family environment, salivary cortisol measurements and children's memory and executive function performance. Salivary cortisol levels of 70 children aged 9 or 10 years were measured before and after performing tasks designed to assess memory and executive functions. Questionnaires on socioeconomic issues, family environment and maternal psychopathologies were administered to participants' families during the children's early childhood and again when they reached school age. Data were analyzed by calculating correlations between variables and conducting hierarchical regression. High cortisol levels were associated with poorer working memory and worse performance in tasks involving executive functions, and were also associated with high scores for maternal psychopathology (during early childhood and school age) and family dysfunction. Family environment variables and changes in cortisol levels explain around 20% of the variance in performance of cognitive tasks. Family functioning and maternal psychopathology in early and middle childhood and children's stress levels were associated with children's working memory and executive functioning.

  7. Proactive and Reactive Composite Scales for the Psychological Inventory of Criminal Thinking Styles (PICTS)

    Science.gov (United States)

    Walters, Glenn D.

    2006-01-01

    The purpose of this study was to construct composite scales for the Psychological Inventory of Criminal Thinking Styles (PICTS) from the PICTS thinking style, factor, and content scales designed to provide general estimates of criminal thinking. The Entitlement thinking style scale, Self-Assertion/Deception factor scale, and Historical content…

  8. Cardiorespiratory fitness does not alter plasma pentraxin 3 and cortisol reactivity to acute psychological stress and exercise.

    Science.gov (United States)

    Huang, Chun-Jung; Webb, Heather E; Beasley, Kathleen N; McAlpine, David A; Tangsilsat, Supatchara E; Acevedo, Edmund O

    2014-03-01

    Pentraxin 3 (PTX3) has been recently identified as a biomarker of vascular inflammation in predicting cardiovascular events. The purpose of this study was to examine the effect of cardiorespiratory fitness on plasma PTX3 and cortisol responses to stress, utilizing a dual-stress model. Fourteen male subjects were classified into high-fit (HF) and low-fit (LF) groups and completed 2 counterbalanced experimental conditions. The exercise-alone condition (EAC) consisted of cycling at 60% maximal oxygen uptake for 37 min, while the dual-stress condition (DSC) included 20 min of a mental stress while cycling for 37 min. Plasma PTX3 revealed significant increases over time with a significant elevation at 37 min in both HF and LF groups in response to EAC and DSC. No difference in plasma PTX3 levels was observed between EAC and DSC. In addition, plasma cortisol revealed a significant condition by time interaction with greater levels during DSC at 37 min, whereas cardiorespiratory fitness level did not reveal different plasma cortisol responses in either the EAC or DSC. Aerobic exercise induces plasma PTX3 release, while additional acute mental stress, in a dual-stress condition, does not exacerbate or further modulate the PTX3 response. Furthermore, cardiorespiratory fitness may not affect the stress reactivity of plasma PTX3 to physical and combined physical and psychological stressors. Finally, the exacerbated cortisol responses to combined stress may provide the potential link to biological pathways that explain changes in physiological homeostasis that may be associated with an increase in the risk of cardiovascular disease.

  9. Overprotective social support leads to increased cardiovascular and subjective stress reactivity.

    Science.gov (United States)

    Zniva, Richard; Pauli, Paul; Schulz, Stefan M

    2017-02-01

    Self-determination theory suggests that autonomy-enhancing social support helps individuals to perceive stressors as challenging rather than stressing. Overprotective support may reduce stress in the short-run but undermines autonomy, thus hampering stress-coping in the long run, particularly when social support is terminated. Heartrate, blood-pressure and ratings were examined in N=44 undergraduate students receiving autonomy support (calculation steps) or overprotection (solutions) from a close friend or no support for solving arithmetic tasks as well as during a subsequent stress-challenge (solving arithmetic tasks alone). Overprotection resulted in increased heartrate, diastolic blood-pressure, stress ratings, and decreased subjective control during stress-challenge. Autonomy support did not lead to unfavorable stress responding. The current findings are in line with assumptions derived from self-determination theory and indicate that autonomy support can help to prevent stress. Overprotection does not buffer stress and is associated with increased stress when discontinued. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Predicting stress from the ability to eavesdrop on feelings: Emotional intelligence and testosterone jointly predict cortisol reactivity.

    Science.gov (United States)

    Bechtoldt, Myriam N; Schneider, Vanessa K

    2016-09-01

    While emotional intelligence (EI) is recognized as a resource in social interactions, we hypothesized a positive association with stress in socially evaluative contexts. In particular, we expected emotion recognition, the core component of EI, to inflict stress on individuals in negatively valenced interactions. We expected this association to be stronger for status-driven individuals, that is, for individuals scoring high on basal testosterone. In a laboratory experiment, N = 166 male participants underwent the Trier Social Stress Test (Kirschbaum, Pirke, & Hellhammer, 1993). As expected, EI measured by the Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT V2.0; Mayer et al., 2003) predicted higher cortisol reactivity, including slower recovery from stress. The effect was moderated by basal testosterone, such that the association was positive when basal testosterone was high but not when it was low. On the component level of EI, the interaction was replicated for negative emotion recognition. These findings lend support to the hypothesis that EI is associated with higher activity of the hypothalamic-pituitary-adrenal axis in contexts where social status is at stake, particularly for those individuals who are more status-driven. Thus, the effects of EI are not unequivocally positive: While EI may positively affect the course of social interactions, it also inflicts stress on the emotionally intelligent individuals themselves. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  11. Meso-Scale Experimental & Numerical Studies for Predicting Macro-scale Performance of Advanced Reactive Materials (ARMs)

    Science.gov (United States)

    2015-04-01

    to full density at ~0.5 GPa, while the crush-up stress for flake -Ni+Al mixtures of similar size is ~2 GPa, and that of nano-sized Ni+Al was ~6 GPa...13 However, flake -Ni+Al mixtures reacted at the lowest threshold stress, due to the additional bending and buckling modes that cause the flake -Ni...volume, Sv, via the relationship, Sv=2PL. The aluminum powder compacts were affixed to the lapped end of a copper projectile (38.1mm high x 7.62mm

  12. The relationship of chronic and momentary work stress to cardiac reactivity in female managers: feasibility of a smart phone-assisted assessment system.

    Science.gov (United States)

    Lumley, Mark A; Shi, Weisong; Wiholm, Clairy; Slatcher, Richard B; Sandmark, Helene; Wang, Shinan; Hytter, Anders; Arnetz, Bengt B

    2014-09-01

    To evaluate a wireless smart phone-assisted (SPA) system that assesses ongoing heart rate (HR) and HR-triggered participant reports of momentary stress when HR is elevated during daily life. This SPA system was used to determine the independent and interactive roles of chronic and momentary work stress on HR reactivity among female managers. A sample of 40 female managers reported their chronic work stress and wore the SPA system during a regular workday. They provided multiple reports of their momentary stress, both when triggered by increased HR and at random times. Relationships among chronic stress, momentary stress, and HR were analyzed with hierarchical linear modeling. Both chronic work stress (b = 0.08, standard error [SE] = 0.03, p = .003) and momentary work stress (b = 1.25, SE = 0.62, p = .052) independently predicted greater HR reactivity, adjusting for baseline HR, age, smoking, caffeine, alcohol use, and momentary physical activity levels. More importantly, chronic and momentary stress significantly interacted (b = 1.00, SE = 0.04, p = .036); high momentary stress predicted elevated HR only in the context of high chronic stress. Female managers who experience chronic work stress displayed elevated cardiac reactivity during momentary stress at work. The joint assessment of chronic stress and momentary stress and their relationship to physiological functioning during work clarifies the potential health risks associated with work stress. Moreover, this wireless SPA system captures the immediate subjective context of individuals when physiological arousal occurs, which may lead to tailored stress management programs in the workplace.

  13. Immediate and long-term effects of meditation on acute stress reactivity, cognitive functions, and intelligence.

    Science.gov (United States)

    Singh, Yogesh; Sharma, Ratna; Talwar, Anjana

    2012-01-01

    With the current globalization of the world's economy and demands for enhanced performance, stress is present universally. Life's stressful events and daily stresses cause both deleterious and cumulative effects on the human body. The practice of meditation might offer a way to relieve that stress. The research team intended to study the effects of meditation on stress-induced changes in physiological parameters, cognitive functions, intelligence, and emotional quotients. The research team conducted the study in two phases, with a month between them. Each participant served as his own control, and the first phase served as the control for the second phase. In phase 1, the research team studied the effects of a stressor (10 minutes playing a computer game) on participants' stress levels. In phase 2, the research team examined the effects of meditation on stress levels. The research team conducted the study in a lab setting at the All India Institute of Medical Sciences (AIIMS), New Delhi, India. The participants were 34 healthy, male volunteers who were students. To study the effects of long-term meditation on stress levels, intelligence, emotional quotients, and cognitive functions participants meditated daily for 1 month, between phases 1 and 2. To study the immediate effects of meditation on stress levels, participants meditated for 15 minutes after playing a computer game to induce stress. The research team measured galvanic skin response (GSR), heart rate (HR), and salivary cortisol and administered tests for the intelligence and emotional quotients (IQ and EQ), acute and perceived stress (AS and PS), and cognitive functions (ie, the Sternberg memory test [short-term memory] and the Stroop test [cognitive flexibility]). Using a pre-post study design, the team performed this testing (1) prior to the start of the study (baseline); (2) in phase 1, after induced stress; (3) in part 1 of phase 2, after 1 month of daily meditation, and (4) in part 2 of phase 2, after

  14. Heated hatha yoga to target cortisol reactivity to stress and affective eating in women at risk for obesity-related illnesses: A randomized controlled trial.

    Science.gov (United States)

    Hopkins, Lindsey B; Medina, Johnna L; Baird, Scarlett O; Rosenfield, David; Powers, Mark B; Smits, Jasper A J

    2016-06-01

    Cortisol reactivity to stress is associated with affective eating, an important behavioral risk factor for obesity and related metabolic diseases. Yoga practice is related to decreases in stress and cortisol levels, thus emerging as a potential targeted complementary intervention for affective eating. This randomized controlled trial examined the efficacy of a heated, hatha yoga intervention for reducing cortisol reactivity to stress and affective eating. Females (N = 52; ages 25-46 years; 75% White) at risk for obesity and related illnesses were randomly assigned to 8 weeks of Bikram Yoga practice or to waitlist control. Cortisol reactivity to a laboratory stress induction were measured at Weeks 0 (pretreatment) and 9 (posttreatment). Self-reported binge eating frequency and coping motives for eating were assessed at Weeks 0, 3, 6, and 9. Among participants with elevated cortisol reactivity at pretreatment ("high reactors"), those randomized to the yoga condition evidenced greater pre- to posttreatment reductions in cortisol reactivity (p = .042, d = .85), but there were not significant condition differences for the "low reactors" (p = .178, d = .53). Yoga participants reported greater decreases in binge eating frequency (p = .040, d = .62) and eating to cope with negative affect (p = .038, d = .54). This study provides preliminary support for the efficacy of heated hatha yoga for treating physiological stress reactivity and affective eating among women at risk for obesity-related illnesses. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  15. Multi-Wave Prospective Examination of the Stress-Reactivity Extension of Response Styles Theory of Depression in High-Risk Children and Early Adolescents

    Science.gov (United States)

    Abela, John R. Z.; Hankin, Benjamin L.; Sheshko, Dana M.; Fishman, Michael B.; Stolow, Darren

    2012-01-01

    The current study tested the stress-reactivity extension of response styles theory of depression (Nolen-Hoeksema "Journal of Abnormal Psychology" 100:569-582, 1991) in a sample of high-risk children and early adolescents from a vulnerability-stress perspective using a multi-wave longitudinal design. In addition, we examined whether obtained…

  16. Heated hatha yoga to target cortisol reactivity to stress and affective eating in women at risk for obesity-related illnesses: A randomized controlled trial

    NARCIS (Netherlands)

    Hopkins, L.B.; Medina, J.L.; Baird, S.O.; Rosenfield, D.; Powers, M.B.; Smits, J.A.J.

    2016-01-01

    Objective: Cortisol reactivity to stress is associated with affective eating, an important behavioral risk factor for obesity and related metabolic diseases. Yoga practice is related to decreases in stress and cortisol levels, thus emerging as a potential targeted complementary intervention for

  17. Krebs Cycle Intermediates Protective against Oxidative Stress by Modulating the Level of Reactive Oxygen Species in Neuronal HT22 Cells

    Directory of Open Access Journals (Sweden)

    Kenta Sawa

    2017-03-01

    Full Text Available Krebs cycle intermediates (KCIs are reported to function as energy substrates in mitochondria and to exert antioxidants effects on the brain. The present study was designed to identify which KCIs are effective neuroprotective compounds against oxidative stress in neuronal cells. Here we found that pyruvate, oxaloacetate, and α-ketoglutarate, but not lactate, citrate, iso-citrate, succinate, fumarate, or malate, protected HT22 cells against hydrogen peroxide-mediated toxicity. These three intermediates reduced the production of hydrogen peroxide-activated reactive oxygen species, measured in terms of 2′,7′-dichlorofluorescein diacetate fluorescence. In contrast, none of the KCIs—used at 1 mM—protected against cell death induced by high concentrations of glutamate—another type of oxidative stress-induced neuronal cell death. Because these protective KCIs did not have any toxic effects (at least up to 10 mM, they have potential use for therapeutic intervention against chronic neurodegenerative diseases.

  18. Stress and piezoelectric properties of aluminum nitride thin films deposited onto metal electrodes by pulsed direct current reactive sputtering

    International Nuclear Information System (INIS)

    Dubois, Marc-Alexandre; Muralt, Paul

    2001-01-01

    Polycrystalline aluminum nitride thin films were deposited onto platinum, aluminum, and titanium electrodes by reactive magnetron sputtering in the pulsed direct current mode. The films exhibited all a columnar microstructure and a c-axis texture. The built-in stress and the piezoelectric properties of these films were studied as a function of both the processing conditions and the electrode material. Stress was found to be very much dependent on the growth conditions, and values ranging from strong compression to high tension were observed. The piezoelectric d 33,f coefficient was shown to rely on substrate quality and ionic bombardment: The nucleation surface must be stable with regard to the nitrogen plasma and present a hexagonal symmetry and, on the other hand, enough energy must be delivered to the growing film through ionic bombardment. [copyright] 2001 American Institute of Physics

  19. GABAergic Signaling within a Limbic-Hypothalamic Circuit Integrates Social and Anxiety-Like Behavior with Stress Reactivity.

    Science.gov (United States)

    Myers, Brent; Carvalho-Netto, Eduardo; Wick-Carlson, Dayna; Wu, Christine; Naser, Sam; Solomon, Matia B; Ulrich-Lai, Yvonne M; Herman, James P

    2016-05-01

    The posterior hypothalamic nucleus (PH) stimulates autonomic stress responses. However, the role of the PH in behavioral correlates of psychiatric illness, such as social and anxiety-like behavior, is largely unexplored, as is the neurochemistry of PH connectivity with limbic and neuroendocrine systems. Thus, the current study tested the hypothesis that GABAergic signaling within the PH is a critical link between forebrain behavior-regulatory nuclei and the neuroendocrine hypothalamus, integrating social and anxiety-related behaviors with physiological stress reactivity. To address this hypothesis, GABAA receptor pharmacology was used to locally inhibit or disinhibit the PH immediately before behavioral measures of social and anxiety-like behavior in rats. Limbic connectivity of the PH was then established by simultaneous co-injection of anterograde and retrograde tracers. Further, the role of PH GABAergic signaling in neuroendocrine stress responses was tested via inhibition/disinhibition of the PH. These studies determined a prominent role for the PH in the expression of anxiety-related behaviors and social withdrawal. Histological analyses revealed divergent stress-activated limbic input to the PH, emanating predominantly from the prefrontal cortex, lateral septum, and amygdala. PH projections also targeted both parvicellular and magnocellular peptidergic neurons in the paraventricular and supraoptic hypothalamus. Further, GABAA receptor pharmacology determined an excitatory effect of the PH on neuroendocrine responses to stress. These data indicate that the PH represents an important stress-integrative center, regulating behavioral processes and connecting the limbic forebrain with neuroendocrine systems. Moreover, the PH appears to be uniquely situated to have a role in stress-related pathologies associated with limbic-hypothalamic dysfunction.

  20. Scaling of Anomalous Hall Effects in Facing-Target Reactively Sputtered Fe4N Films

    KAUST Repository

    Zhang, Yan; Mi, Wenbo; Wang, Xiaocha; Zhang, Xixiang

    2015-01-01

    boundaries scattering have a major impact on the AHE scaling law. The scaling exponent γ in the conventional scaling of is larger than 2 in both the epitaxial and polycrystalline γ′-Fe4N films. Although γ>2 has been found in heterogeneous systems due

  1. Rhythmicity in mice selected for extremes in stress reactivity: behavioural, endocrine and sleep changes resembling endophenotypes of major depression.

    Directory of Open Access Journals (Sweden)

    Chadi Touma

    Full Text Available Dysregulation of the hypothalamic-pituitary-adrenal (HPA axis, including hyper- or hypo-activity of the stress hormone system, plays a critical role in the pathophysiology of mood disorders such as major depression (MD. Further biological hallmarks of MD are disturbances in circadian rhythms and sleep architecture. Applying a translational approach, an animal model has recently been developed, focusing on the deviation in sensitivity to stressful encounters. This so-called 'stress reactivity' (SR mouse model consists of three separate breeding lines selected for either high (HR, intermediate (IR, or low (LR corticosterone increase in response to stressors.In order to contribute to the validation of the SR mouse model, our study combined the analysis of behavioural and HPA axis rhythmicity with sleep-EEG recordings in the HR/IR/LR mouse lines. We found that hyper-responsiveness to stressors was associated with psychomotor alterations (increased locomotor activity and exploration towards the end of the resting period, resembling symptoms like restlessness, sleep continuity disturbances and early awakenings that are commonly observed in melancholic depression. Additionally, HR mice also showed neuroendocrine abnormalities similar to symptoms of MD patients such as reduced amplitude of the circadian glucocorticoid rhythm and elevated trough levels. The sleep-EEG analyses, furthermore, revealed changes in rapid eye movement (REM and non-REM sleep as well as slow wave activity, indicative of reduced sleep efficacy and REM sleep disinhibition in HR mice.Thus, we could show that by selectively breeding mice for extremes in stress reactivity, clinically relevant endophenotypes of MD can be modelled. Given the importance of rhythmicity and sleep disturbances as biomarkers of MD, both animal and clinical studies on the interaction of behavioural, neuroendocrine and sleep parameters may reveal molecular pathways that ultimately lead to the discovery of new

  2. The Buffer Effect of Therapy Dog Exposure on Stress Reactivity in Undergraduate Students.

    Science.gov (United States)

    Fiocco, Alexandra J; Hunse, Anastasia M

    2017-06-30

    Stress is an insidious health risk that is commonly reported among university students. While research suggests that dog exposure may facilitate recovery from a stress response, little is known about the buffer effect of dog exposure on the stress response to a future stressor. This study examined whether interaction with a therapy dog could reduce the strength of the physiological stress response when exposed to a subsequent stressor. Sixty-one university students were randomly assigned to either a therapy dog (TD, n = 31) or a no-dog control (C, n = 30) group. The stress response was measured by electrodermal activity (EDA) in response to the Paced Auditory Serial Addition Test (PASAT). Participants also completed questionnaires that assessed pet attitude, general stress levels, and affect. Analyses of covariance (ANCOVAs) showed that increase in EDA was significantly more pronounced in the C group than in the TD group ( p stress response in university students, which has implications for the promotion of a viable stress management program on university campuses.

  3. Stress and Emotional Reactivity as Explanations for Gender Differences in Adolescents' Depressive Symptoms

    Science.gov (United States)

    Charbonneau, Anna M.; Mezulis, Amy H.; Hyde, Janet Shibley

    2009-01-01

    In this longitudinal study, we examined whether certain types of stressful events and how individuals respond to these events would explain gender differences in depressive symptoms among adolescents. We hypothesized that certain stressful events would mediate the relationship between gender and depressive symptoms. We also hypothesized that…

  4. The Buffer Effect of Therapy Dog Exposure on Stress Reactivity in Undergraduate Students

    Directory of Open Access Journals (Sweden)

    Alexandra J. Fiocco

    2017-06-01

    Full Text Available Stress is an insidious health risk that is commonly reported among university students. While research suggests that dog exposure may facilitate recovery from a stress response, little is known about the buffer effect of dog exposure on the stress response to a future stressor. This study examined whether interaction with a therapy dog could reduce the strength of the physiological stress response when exposed to a subsequent stressor. Sixty-one university students were randomly assigned to either a therapy dog (TD, n = 31 or a no-dog control (C, n = 30 group. The stress response was measured by electrodermal activity (EDA in response to the Paced Auditory Serial Addition Test (PASAT. Participants also completed questionnaires that assessed pet attitude, general stress levels, and affect. Analyses of covariance (ANCOVAs showed that increase in EDA was significantly more pronounced in the C group than in the TD group (p < 0.01. Pet attitudes did not modulate the buffer effect of therapy dog exposure. Results suggest that therapy dog exposure may buffer the stress response in university students, which has implications for the promotion of a viable stress management program on university campuses.

  5. Stress Reactivity of Six-Year-Old Children Involved in Challenging Tasks

    Science.gov (United States)

    Sajaniemi, Nina; Suhonen, Eira; Kontu, Elina; Lindholm, Harri; Hirvonen, Ari

    2012-01-01

    The aim of this study was to investigate whether the preschool activities challenge the stress regulative system in children. We used a multi-system approach to evaluate the underlying processes of stress responses and measured both cortisol and [alpha]-amylase responses after emotionally and cognitively challenging tasks followed by a recovery…

  6. OSO paradigm--A rapid behavioral screening method for acute psychosocial stress reactivity in mice.

    Science.gov (United States)

    Brzózka, M M; Unterbarnscheidt, T; Schwab, M H; Rossner, M J

    2016-02-09

    Chronic psychosocial stress is an important environmental risk factor for the development of psychiatric diseases. However, studying the impact of chronic psychosocial stress in mice is time consuming and thus not optimally suited to 'screen' increasing numbers of genetically manipulated mouse models for psychiatric endophenotypes. Moreover, many studies focus on restraint stress, a strong physical stressor with limited relevance for psychiatric disorders. Here, we describe a simple and a rapid method based on the resident-intruder paradigm to examine acute effects of mild psychosocial stress in mice. The OSO paradigm (open field--social defeat--open field) compares behavioral consequences on locomotor activity, anxiety and curiosity before and after exposure to acute social defeat stress. We first evaluated OSO in male C57Bl/6 wildtype mice where a single episode of social defeat reduced locomotor activity, increased anxiety and diminished exploratory behavior. Subsequently, we applied the OSO paradigm to mouse models of two schizophrenia (SZ) risk genes. Transgenic mice with neuronal overexpression of Neuregulin-1 (Nrg1) type III showed increased risk-taking behavior after acute stress exposure suggesting that NRG1 dysfunction is associated with altered affective behavior. In contrast, Tcf4 transgenic mice displayed a normal stress response which is in line with the postulated predominant contribution of TCF4 to cognitive deficits of SZ. In conclusion, the OSO paradigm allows for rapid screening of selected psychosocial stress-induced behavioral endophenotypes in mouse models of psychiatric diseases. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

  7. Fear of pain and cortisol reactivity predict the strength of stress-induced hypoalgesia

    NARCIS (Netherlands)

    Timmers, Inge; Kaas, Amanda L.; Quaedflieg, Conny Wem; Biggs, Emma E.; Smeets, Tom; de Jong, Jeroen R.

    2018-01-01

    BACKGROUND: Acute stress can have an effect on pain sensitivity, yet the direction of the effect - whether it is hypoalgesic or hyperalgesic - is mixed across studies. Moreover, which part of the stress response influences pain sensitivity is still unclear. In the current experimental study, we aim

  8. Examining perceptions of academic stress and its sources among university students: The Perception of Academic Stress Scale

    Directory of Open Access Journals (Sweden)

    Dalia Bedewy

    2015-07-01

    Full Text Available The development of a scale to measure perceived sources of academic stress among university students. Based on empirical evidence and recent literature review, we developed an 18-item scale to measure perceptions of academic stress and its sources. Experts ( n  = 12 participated in the content validation process of the instrument before it was administered to ( n  = 100 students. The developed instrument has internal consistency reliability of 0.7 (Cronbach’s alpha, there was evidence for content validity, and factor analysis resulted in four correlated and theoretically meaningful factors. We developed and tested a scale to measure academic stress and its sources. This scale takes 5 minutes to complete.

  9. Clarifying relations between dispositional aggression and brain potential response: overlapping and distinct contributions of impulsivity and stress reactivity.

    Science.gov (United States)

    Venables, Noah C; Patrick, Christopher J; Hall, Jason R; Bernat, Edward M

    2011-03-01

    Impulsive-aggressive individuals exhibit deficits in amplitude of the P3 brain potential response, however, it remains unclear how separable dispositional traits account for this association. The current study sought to clarify the basis of this association by examining contributions of trait impulsiveness and stress reactivity to the observed relationship between dispositional aggression and amplitude of the P3 brain potential response in a visual novelty-oddball procedure. A significant negative association was found between aggressiveness and amplitude of P3 response to both target and novel stimuli over frontal-central scalp sites. Impulsivity showed a parallel inverse relationship with P3 amplitude, attributable to its overlap with dispositional aggression. In contrast, stress reactivity did not exhibit a zero-order association with P3 amplitude, but modestly predicted P3 in a positive direction after accounting for its overlap with aggression. Results are discussed in terms of their implications for individual difference variables and brain processes underlying impulsive-aggressive behavior. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Listening to music and physiological and psychological functioning: the mediating role of emotion regulation and stress reactivity.

    Science.gov (United States)

    Thoma, M V; Scholz, U; Ehlert, U; Nater, U M

    2012-01-01

    Music listening has been suggested to have short-term beneficial effects. The aim of this study was to investigate the association and potential mediating mechanisms between various aspects of habitual music-listening behaviour and physiological and psychological functioning. An internet-based survey was conducted in university students, measuring habitual music-listening behaviour, emotion regulation, stress reactivity, as well as physiological and psychological functioning. A total of 1230 individuals (mean = 24.89 ± 5.34 years, 55.3% women) completed the questionnaire. Quantitative aspects of habitual music-listening behaviour, i.e. average duration of music listening and subjective relevance of music, were not associated with physiological and psychological functioning. In contrast, qualitative aspects, i.e. reasons for listening (especially 'reducing loneliness and aggression', and 'arousing or intensifying specific emotions') were significantly related to physiological and psychological functioning (all p = 0.001). These direct effects were mediated by distress-augmenting emotion regulation and individual stress reactivity. The habitual music-listening behaviour appears to be a multifaceted behaviour that is further influenced by dispositions that are usually not related to music listening. Consequently, habitual music-listening behaviour is not obviously linked to physiological and psychological functioning.

  11. The Hysteretic Behavior of Partially Pre-Stressed Beam-Column Joint Sub-assemblages Made of Reactive Powder Concrete

    Directory of Open Access Journals (Sweden)

    Siti Aisyah Nurjannah

    2016-11-01

    Full Text Available Reactive powder concrete (RPC is an alternative to normal concrete (NC allowing for significantly higher strength of partially pre-stressed concrete structures. In the Indonesian national standard SNI 03-2847-2013 (2013 and the American standard ACI 318-14 (2014, the partial pre-stressed ratio (PPR is limited to a maximum of 25.0 percent to ensure that pre-stressed concrete structures remain ductile and capable to dissipate seismic energy sufficiently. The objective of this experimental study was to investigate the hysteretic performance of partially pre-stressed-RPC (PP-RPC for both interior and exterior beam-column joint sub-assemblages. Four specimens with different levels of PPR were tested with a combination of constant axial compression and cyclic lateral loads. The PPR used for the first and the second two specimens were 22.8% and 33.8%, respectively. The strength of the RPC was 101.60 MPa for all specimens. The results showed that increasing the PPR of PP-RPC improves its hysteretic performance. The best performing specimen, with a PPR of 33.8%, had a ductility that was 1.97 times that of the specimen with a PPR of 22.8%.

  12. A translational investigation targeting stress-reactivity and prefrontal cognitive control with guanfacine for smoking cessation.

    Science.gov (United States)

    McKee, Sherry A; Potenza, Marc N; Kober, Hedy; Sofuoglu, Mehmet; Arnsten, Amy F T; Picciotto, Marina R; Weinberger, Andrea H; Ashare, Rebecca; Sinha, Rajita

    2015-03-01

    Stress and prefrontal cognitive dysfunction have key roles in driving smoking; however, there are no therapeutics for smoking cessation that attenuate the effects of stress on smoking and enhance cognition. Central noradrenergic pathways are involved in stress-induced reinstatement to nicotine and in the prefrontal executive control of adaptive behaviors. We used a novel translational approach employing a validated laboratory analogue of stress-precipitated smoking, functional magnetic resonance imaging (fMRI), and a proof-of-concept treatment period to evaluate whether the noradrenergic α2a agonist guanfacine (3 mg/day) versus placebo (0 mg/day) reduced stress-precipitated smoking in the laboratory, altered cortico-striatal activation during the Stroop cognitive-control task, and reduced smoking following a quit attempt. In nicotine-deprived smokers (n=33), stress versus a neutral condition significantly decreased the latency to smoke, and increased tobacco craving, ad-libitum smoking, and systolic blood pressure in placebo-treated subjects, and these effects were absent or reduced in guanfacine-treated subjects. Following stress, placebo-treated subjects demonstrated decreased cortisol levels whereas guanfacine-treated subjects demonstrated increased levels. Guanfacine, compared with placebo, altered prefrontal activity during a cognitive-control task, and reduced cigarette use but did not increase complete abstinence during treatment. These preliminary laboratory, neuroimaging, and clinical outcome data were consistent and complementary and support further development of guanfacine for smoking cessation. © The Author(s) 2014.

  13. Psychometric Validation of Stress and Compliance Scale for ...

    African Journals Online (AJOL)

    Purpose: To provide factorial analytical findings, and to construct validation and normative .... participants were asked to fold the questionnaire ... both cross loaded onto both factors. .... Compas B, Grant K. Ey S. Psychosocial stress and child.

  14. Contribution to the study of the interactions between residual stresses and oxygen dissolution in a reactive deformable solid

    International Nuclear Information System (INIS)

    Raceanu, Laura

    2011-01-01

    The aim of this PhD work is to highlight the interactions between the mechanical stress and the chemical composition within diffusion of matter process for a reactive solid. The chronological evolution of our work goes from a parametric numerical study to an experimental study and reveals the role of mechanical stresses on the oxygen diffusion process. Different origins of mechanical stress were first numerically analysed from the point of view of their impacts on the process of oxygen diffusion into a metal (Zr) or a ceramic (UO 2 ) subjected to an oxidizing environment. This approach allowed us: - to identify a surface treatment (shot-peening) able to generate a residual specific stress field, as a starting point for an experimental study implementation in order to validate the numerical study conclusions; - to highlight the ability of the stress field on the stabilisation of the morphology of an undulated metal/oxide interface (case of Zr). In the experimental approach, different techniques were used to characterize the material (GDOS, SEM, TGA, hole-drilling method, micro-hardness tests). They permitted the detection of a strong influence of shot-peening on the oxidation rate. The comparison of experimental and numerical simulation results reveals strong interactions between stress and compositions fields induced by the different treatments (shot-peening and/or pre-oxidation). This study opens up many opportunities in the understanding of multi-physics coupling effects being very useful for the optimization of mechanical and chemical surface-treatments, able furthermore to favour the diffusion (nitriding, cementation) or to slow it down (corrosion). (author) [fr

  15. B-Type Natriuretic Peptide Reactivity to Mental Stress and Exercise: Role of Obesity and Hemodynamics

    Science.gov (United States)

    2009-08-25

    Clinically, BNP is important in diagnosis/ differential diagnosis in individuals with suspected HF, with a decision cut-point of 100 pg/ml now accepted as...the context of obesity-related disparity in BNP levels or action. Based on the differential hemodynamic reactivity patterns associated with...Arch Intern Med. 2004, 164:2247- 2252. 124 141. Mehra MR, Uber PA, Park MH, et al.: Obesity and suppressed B-type natriuretic peptide levels in

  16. Blood Pressure Reactivity to Psychological Stress in Young Adults and Cognition in Midlife: The Coronary Artery Risk Development in Young Adults (CARDIA) Study.

    Science.gov (United States)

    Yano, Yuichiro; Ning, Hongyan; Reis, Jared P; Lewis, Cora E; Launer, Lenore J; Bryan, R Nick; Yaffe, Kristine; Sidney, Stephen; Albanese, Emiliano; Greenland, Philip; Lloyd-Jones, Donald; Liu, Kiang

    2016-01-13

    The classic view of blood pressure (BP) reactivity to psychological stress in relation to cardiovascular risks assumes that excess reactivity is worse and lower reactivity is better. Evidence addressing how stress-induced BP reactivity in young adults is associated with midlife cognitive function is sparse. We assessed BP reactivity during a star tracing task and a video game in adults aged 20 to 32 years. Twenty-three years later, cognitive function was assessed with use of the Digit Symbol Substitution Test (a psychomotor speed test), the Rey Auditory Verbal Learning Test (a verbal memory test), and the modified Stroop test (an executive function test). At the time of follow-up, participants (n=3021) had a mean age of 50.2 years; 56% were women, and 44% were black. In linear regression models adjusted for demographic and clinical characteristics including baseline and follow-up resting BP, lower systolic BP (SBP) reactivity during the star tracing and video game was associated with worse Digit Symbol Substitution Test scores (β [SE]: 0.11 [0.02] and 0.05 [0.02], respectively) and worse performance on the Stroop test (β [SE]: -0.06 [0.02] and -0.05 [0.02]; all Pstress-induced SBP reactivity in younger adults was associated with lower cognitive function in midlife. BP reactivity to psychological stressors may have different associations with target organs in hypertension. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

  17. Effects of Aerobic Exercise Training on Stress Reactivity in Every-Day Life

    OpenAIRE

    Haaren, Birte von

    2015-01-01

    The current thesis investigated the effects of a 20-week aerobic exercise training on physiological and emotional responses to real-life stress using a randomized, controlled trial and an inactive sample. To assess participants' physiological and psychological responses during everyday life, ambulatory assessment was used. In summary, the present thesis provides empirical support that regular exercise can lead to improved emotional and physiological responses during real-life stress.

  18. Direct coupling of a genome-scale microbial in silico model and a groundwater reactive transport model

    International Nuclear Information System (INIS)

    Fang, Yilin; Scheibe, Timothy D.; Mahadevan, Radhakrishnan; Garg, Srinath; Long, Philip E.; Lovley, Derek R.

    2011-01-01

    The activity of microorganisms often plays an important role in dynamic natural attenuation or engineered bioremediation of subsurface contaminants, such as chlorinated solvents, metals, and radionuclides. To evaluate and/or design bioremediated systems, quantitative reactive transport models are needed. State-of-the-art reactive transport models often ignore the microbial effects or simulate the microbial effects with static growth yield and constant reaction rate parameters over simulated conditions, while in reality microorganisms can dynamically modify their functionality (such as utilization of alternative respiratory pathways) in response to spatial and temporal variations in environmental conditions. Constraint-based genome-scale microbial in silico models, using genomic data and multiple-pathway reaction networks, have been shown to be able to simulate transient metabolism of some well studied microorganisms and identify growth rate, substrate uptake rates, and byproduct rates under different growth conditions. These rates can be identified and used to replace specific microbially-mediated reaction rates in a reactive transport model using local geochemical conditions as constraints. We previously demonstrated the potential utility of integrating a constraint based microbial metabolism model with a reactive transport simulator as applied to bioremediation of uranium in groundwater. However, that work relied on an indirect coupling approach that was effective for initial demonstration but may not be extensible to more complex problems that are of significant interest (e.g., communities of microbial species, multiple constraining variables). Here, we extend that work by presenting and demonstrating a method of directly integrating a reactive transport model (FORTRAN code) with constraint-based in silico models solved with IBM ILOG CPLEX linear optimizer base system (C library). The models were integrated with BABEL, a language interoperability tool. The

  19. Direct coupling of a genome-scale microbial in silico model and a groundwater reactive transport model.

    Science.gov (United States)

    Fang, Yilin; Scheibe, Timothy D; Mahadevan, Radhakrishnan; Garg, Srinath; Long, Philip E; Lovley, Derek R

    2011-03-25

    The activity of microorganisms often plays an important role in dynamic natural attenuation or engineered bioremediation of subsurface contaminants, such as chlorinated solvents, metals, and radionuclides. To evaluate and/or design bioremediated systems, quantitative reactive transport models are needed. State-of-the-art reactive transport models often ignore the microbial effects or simulate the microbial effects with static growth yield and constant reaction rate parameters over simulated conditions, while in reality microorganisms can dynamically modify their functionality (such as utilization of alternative respiratory pathways) in response to spatial and temporal variations in environmental conditions. Constraint-based genome-scale microbial in silico models, using genomic data and multiple-pathway reaction networks, have been shown to be able to simulate transient metabolism of some well studied microorganisms and identify growth rate, substrate uptake rates, and byproduct rates under different growth conditions. These rates can be identified and used to replace specific microbially-mediated reaction rates in a reactive transport model using local geochemical conditions as constraints. We previously demonstrated the potential utility of integrating a constraint-based microbial metabolism model with a reactive transport simulator as applied to bioremediation of uranium in groundwater. However, that work relied on an indirect coupling approach that was effective for initial demonstration but may not be extensible to more complex problems that are of significant interest (e.g., communities of microbial species and multiple constraining variables). Here, we extend that work by presenting and demonstrating a method of directly integrating a reactive transport model (FORTRAN code) with constraint-based in silico models solved with IBM ILOG CPLEX linear optimizer base system (C library). The models were integrated with BABEL, a language interoperability tool. The

  20. Direct coupling of a genome-scale microbial in silico model and a groundwater reactive transport model

    Science.gov (United States)

    Fang, Yilin; Scheibe, Timothy D.; Mahadevan, Radhakrishnan; Garg, Srinath; Long, Philip E.; Lovley, Derek R.

    2011-03-01

    The activity of microorganisms often plays an important role in dynamic natural attenuation or engineered bioremediation of subsurface contaminants, such as chlorinated solvents, metals, and radionuclides. To evaluate and/or design bioremediated systems, quantitative reactive transport models are needed. State-of-the-art reactive transport models often ignore the microbial effects or simulate the microbial effects with static growth yield and constant reaction rate parameters over simulated conditions, while in reality microorganisms can dynamically modify their functionality (such as utilization of alternative respiratory pathways) in response to spatial and temporal variations in environmental conditions. Constraint-based genome-scale microbial in silico models, using genomic data and multiple-pathway reaction networks, have been shown to be able to simulate transient metabolism of some well studied microorganisms and identify growth rate, substrate uptake rates, and byproduct rates under different growth conditions. These rates can be identified and used to replace specific microbially-mediated reaction rates in a reactive transport model using local geochemical conditions as constraints. We previously demonstrated the potential utility of integrating a constraint-based microbial metabolism model with a reactive transport simulator as applied to bioremediation of uranium in groundwater. However, that work relied on an indirect coupling approach that was effective for initial demonstration but may not be extensible to more complex problems that are of significant interest (e.g., communities of microbial species and multiple constraining variables). Here, we extend that work by presenting and demonstrating a method of directly integrating a reactive transport model (FORTRAN code) with constraint-based in silico models solved with IBM ILOG CPLEX linear optimizer base system (C library). The models were integrated with BABEL, a language interoperability tool. The

  1. The influence of social stress on time perception and psychophysiological reactivity.

    Science.gov (United States)

    van Hedger, Kathryne; Necka, Elizabeth A; Barakzai, Anam K; Norman, Greg J

    2017-05-01

    Time perception is a fundamental component of everyday life. Although time can be measured using standard units, the relationship between an individual's experience of perceived time and a standard unit is highly sensitive to context. Stressful and threatening stimuli have been previously shown to produce time distortion effects, such that individuals perceive the stimuli as lasting for different amounts of time as compared to a standard unit. As a highly social species, humans are acutely sensitive to social stressors; however, time distortion effects have not been studied in the context of social stress. We collected psychophysiological (electrocardiogram and impedance cardiography) and time perception data before, during, and after a modified version of the Trier Social Stress Test for 42 participants. Based on prior theories and evidence from the time perception literature, we hypothesized that experiencing a stressful event would result in time distortion. This hypothesis was supported by the data, with individuals on average reproducing short and long duration negative and positive stimuli as lasting longer after experiencing social stress, t(41) = -3.55, p = .001, and t(41) = -4.12, p social stress. These findings are in line with some other studies of time distortion, and provide evidence for the interoceptive salience model of time perception. Implications for mechanisms of time distortion are discussed. © 2017 Society for Psychophysiological Research.

  2. Gender Effect According to Item Directionality on the Perceived Stress Scale for Adults with Multiple Sclerosis

    Science.gov (United States)

    Gitchel, W. Dent; Roessler, Richard T.; Turner, Ronna C.

    2011-01-01

    Assessment is critical to rehabilitation practice and research, and self-reports are a commonly used form of assessment. This study examines a gender effect according to item wording on the "Perceived Stress Scale" for adults with multiple sclerosis. Past studies have demonstrated two-factor solutions on this scale and other scales measuring…

  3. Assessing adaptability and reactive scope: Introducing a new measure and illustrating its use through a case study of environmental stress in forest-living baboons.

    Science.gov (United States)

    MacLarnon, A M; Sommer, V; Goffe, A S; Higham, J P; Lodge, E; Tkaczynski, P; Ross, C

    2015-05-01

    In order to maintain regulatory processes, animals are expected to be adapted to the range of environmental stressors usually encountered in their environmental niche. The available capacity of their stress responses is termed their reactive scope, which is utilised to a greater or lesser extent to deal with different stressors. Typically, non-invasive hormone assessment is used to measure the physiological stress responses of wild animals, but, for methodological reasons, such measurements are not directly comparable across studies, limiting interpretation. To overcome this constraint, we propose a new measure of the relative strength of stress responses, 'demonstrated reactive scope', and illustrate its use in a study of ecological correlates (climate, food availability) of faecal glucocorticoid (fGC) levels in two forest-living troops of baboons. Results suggest the wild-feeding troop experiences both thermoregulatory and nutritional stress, while the crop-raiding troop experiences only thermoregulatory stress. This difference, together with the crop-raiding troop's lower overall physiological stress levels and lower demonstrated fGC reactive scope, may reflect nutritional stress-buffering in this troop. The relatively high demonstrated fGC reactive scope levels of both troops compared with other baboons and primate species, may reflect their extreme habitat, on the edge of the geographic range for baboons. Demonstrated reactive scope provides a means of gauging the relative strengths of stress responses of individuals, populations, or species under different conditions, enhancing the interpretive capacity of non-invasive studies of stress hormone levels in wild populations, e.g. in terms of animals' adaptive flexibility, the magnitude of their response to anthropogenic change, or the severity of impact of environmental conditions. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Psychometric Properties of the Children's Scale of Hostility and Aggression: Reactive/Proactive (C-SHARP)

    Science.gov (United States)

    Farmer, Cristan A.; Aman, Michael G.

    2010-01-01

    Although often lacking "malice", aggression is fairly common in children with intellectual or developmental disability (I/DD). Despite this, there are no scales available that are appropriate for an in-depth analysis of aggressive behavior in this population. Such scales are needed for the study of aggressive behavior, which is a common target…

  5. Final Project Report: Release of aged contaminants from weathered sediments: Effects of sorbate speciation on scaling of reactive transport

    Energy Technology Data Exchange (ETDEWEB)

    Jon Chorover, University of Arizona; Peggy O' €™Day, University of California, Merced; Karl Mueller, Penn State University; Wooyong Um, Pacific Northwest National Laboratory; Carl Steefel, Lawrence Berkeley National Laboratory

    2012-10-01

    Hanford sediments impacted by hyperalkaline high level radioactive waste have undergone incongruent silicate mineral weathering concurrent with contaminant uptake. In this project, we studied the impact of background pore water (BPW) on strontium, cesium and iodine desorption and transport in Hanford sediments that were experimentally weathered by contact with simulated hyperalkaline tank waste leachate (STWL) solutions. Using those lab-weathered Hanford sediments (HS) and model precipitates formed during nucleation from homogeneous STWL solutions (HN), we (i) provided detailed characterization of reaction products over a matrix of field-relevant gradients in contaminant concentration, PCO2, and reaction time; (ii) improved molecular-scale understanding of how sorbate speciation controls contaminant desorption from weathered sediments upon removal of caustic sources; and (iii) developed a mechanistic, predictive model of meso- to field-scale contaminant reactive transport under these conditions.

  6. Association of HPA axis-related genetic variation with stress reactivity and aggressive behaviour in pigs

    Directory of Open Access Journals (Sweden)

    Muráni Eduard

    2010-08-01

    Full Text Available Abstract Background Stress, elicited for example by aggressive interactions, has negative effects on various biological functions including immune defence, reproduction, growth, and, in livestock, on product quality. Stress response and aggressiveness are mutually interrelated and show large interindividual variation, partly attributable to genetic factors. In the pig little is known about the molecular-genetic background of the variation in stress responsiveness and aggressiveness. To identify candidate genes we analyzed association of DNA markers in each of ten genes (CRH g.233C>T, CRHR1 c.*866_867insA, CRHBP c.51G>A, POMC c.293_298del, MC2R c.306T>G, NR3C1 c.*2122A>G, AVP c.207A>G, AVPR1B c.1084A>G, UCN g.1329T>C, CRHR2 c.*13T>C related to the hypothalamic-pituitary-adrenocortical (HPA axis, one of the main stress-response systems, with various stress- and aggression-related parameters at slaughter. These parameters were: physiological measures of the stress response (plasma concentrations of cortisol, creatine kinase, glucose, and lactate, adrenal weight (which is a parameter reflecting activity of the central branch of the HPA axis over time and aggressive behaviour (measured by means of lesion scoring in the context of psychosocial stress of mixing individuals with different aggressive temperament. Results The SNP NR3C1 c.*2122A>G showed association with cortisol concentration (p = 0.024, adrenal weight (p = 0.003 and aggressive behaviour (front lesion score, p = 0.012; total lesion score p = 0.045. The SNP AVPR1B c.1084A>G showed a highly significant association with aggressive behaviour (middle lesion score, p = 0.007; total lesion score p = 0.003. The SNP UCN g.1329T>C showed association with adrenal weight (p = 0.019 and aggressive behaviour (front lesion score, p = 0.029. The SNP CRH g.233C>T showed a significant association with glucose concentration (p = 0.002, and the polymorphisms POMC c.293_298del and MC2R c.306T>G with adrenal

  7. Upscaling of Long-Term U9VI) Desorption from Pore Scale Kinetics to Field-Scale Reactive Transport Models

    Energy Technology Data Exchange (ETDEWEB)

    Andy Miller

    2009-01-25

    Environmental systems exhibit a range of complexities which exist at a range of length and mass scales. Within the realm of radionuclide fate and transport, much work has been focused on understanding pore scale processes where complexity can be reduced to a simplified system. In describing larger scale behavior, the results from these simplified systems must be combined to create a theory of the whole. This process can be quite complex, and lead to models which lack transparency. The underlying assumption of this approach is that complex systems will exhibit complex behavior, requiring a complex system of equations to describe behavior. This assumption has never been tested. The goal of the experiments presented is to ask the question: Do increasingly complex systems show increasingly complex behavior? Three experimental tanks at the intermediate scale (Tank 1: 2.4m x 1.2m x 7.6cm, Tank 2: 2.4m x 0.61m x 7.6cm, Tank 3: 2.4m x 0.61m x 0.61m (LxHxW)) have been completed. These tanks were packed with various physical orientations of different particle sizes of a uranium contaminated sediment from a former uranium mill near Naturita, Colorado. Steady state water flow was induced across the tanks using constant head boundaries. Pore water was removed from within the flow domain through sampling ports/wells; effluent samples were also taken. Each sample was analyzed for a variety of analytes relating to the solubility and transport of uranium. Flow fields were characterized using inert tracers and direct measurements of pressure head. The results show that although there is a wide range of chemical variability within the flow domain of the tank, the effluent uranium behavior is simple enough to be described using a variety of conceptual models. Thus, although there is a wide range in variability caused by pore scale behaviors, these behaviors appear to be smoothed out as uranium is transported through the tank. This smoothing of uranium transport behavior transcends

  8. Cortisol reactivity and emotional memory after psychosocial stress in oral contraceptive users.

    Science.gov (United States)

    Mordecai, Kristen L; Rubin, Leah H; Eatough, Erin; Sundermann, Erin; Drogos, Lauren; Savarese, Antonia; Maki, Pauline M

    2017-01-02

    Oral contraceptive (OC) users typically show a blunted or no cortisol response to psychosocial stress. Although most OC regimens include both an inactive (dummy) and active pill phase, studies have not systematically investigated cortisol responses during these pill phases. Further, high levels of cortisol following a stressor diminish retrieval of emotional material, but the effects of stress on memory among OC users are poorly understood. We examined the effects of a psychosocial stressor, the Trier Social Stress Test, vs. a control condition on cortisol responsivity and emotional memory retrieval in women tested either during their active (n = 18) or inactive pill phase (n = 21). In secondary analyses, we quantitatively compared OC users with normally cycling women and showed a significant lack of cortisol response during both active and inactive pill phase. Emotional recall did not differ between active and inactive pill phases. Stress differentially diminished recall of negative words compared with positive or neutral words, but cortisol levels were unrelated to memory performance. These findings indicate that OC users have distinct cortisol and memory responses to stress that are similar between the active and inactive pill phases. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  9. Colorimetric Detection of Caspase 3 Activity and Reactive Oxygen Derivatives: Potential Early Indicators of Thermal Stress in Corals

    Directory of Open Access Journals (Sweden)

    Mickael Ros

    2016-01-01

    Full Text Available There is an urgent need to develop and implement rapid assessments of coral health to allow effective adaptive management in response to coastal development and global change. There is now increasing evidence that activation of caspase-dependent apoptosis plays a key role during coral bleaching and subsequent mortality. In this study, a “clinical” approach was used to assess coral health by measuring the activity of caspase 3 using a commercial kit. This method was first applied while inducing thermal bleaching in two coral species, Acropora millepora and Pocillopora damicornis. The latter species was then chosen to undergo further studies combining the detection of oxidative stress-related compounds (catalase activity and glutathione concentrations as well as caspase activity during both stress and recovery phases. Zooxanthellae photosystem II (PSII efficiency and cell density were measured in parallel to assess symbiont health. Our results demonstrate that the increased caspase 3 activity in the coral host could be detected before observing any significant decrease in the photochemical efficiency of PSII in the algal symbionts and/or their expulsion from the host. This study highlights the potential of host caspase 3 and reactive oxygen species scavenging activities as early indicators of stress in individual coral colonies.

  10. Geometry-coupled reactive fluid transport at the fracture scale -Application to CO 2 geologic storage

    KAUST Repository

    Kim, Seunghee

    2015-08-19

    Water acidification follows CO2 injection and leads to reactive fluid transport through pores and rock fractures, with potential implications to reservoirs and wells in CO2 geologic storage and enhanced oil recovery. Kinetic rate laws for dissolution reactions in calcite and anorthite are combined with Navier-Stokes law and advection-diffusion transport to perform geometry-coupled numerical simulations in order to study the evolution of chemical reactions, species concentration and fracture morphology. Results are summarized as a function of two dimensionless parameters: the Damköhler number Da which is the ratio between advection and reaction times, and the transverse Peclet number Pe defined as the ratio between the time for diffusion across the fracture and the time for advection along the fracture. Reactant species are readily consumed near the inlet in a carbonate reservoir when the flow velocity is low (low transverse Peclet number and Da>10-1). At high flow velocities, diffusion fails to homogenize the concentration field across the fracture (high transverse Peclet number Pe>10-1). When the reaction rate is low as in anorthite reservoirs (Da<10-1) reactant species are more readily transported towards the outlet. At a given Peclet number, a lower Damköhler number causes the flow channel to experience a more uniform aperture enlargement along the length of the fracture. When the length-to-aperture ratio is sufficiently large, say l/d>30, the system response resembles the solution for 1-D reactive fluid transport. A decreased length-to-aperture ratio slows the diffusive transport of reactant species to the mineral fracture surface, and analyses of fracture networks must take into consideration both the length and slenderness of individual fractures in addition to Pe and Da numbers.

  11. Geometry-coupled reactive fluid transport at the fracture scale -Application to CO 2 geologic storage

    KAUST Repository

    Kim, Seunghee; Santamarina, Carlos

    2015-01-01

    Water acidification follows CO2 injection and leads to reactive fluid transport through pores and rock fractures, with potential implications to reservoirs and wells in CO2 geologic storage and enhanced oil recovery. Kinetic rate laws for dissolution reactions in calcite and anorthite are combined with Navier-Stokes law and advection-diffusion transport to perform geometry-coupled numerical simulations in order to study the evolution of chemical reactions, species concentration and fracture morphology. Results are summarized as a function of two dimensionless parameters: the Damköhler number Da which is the ratio between advection and reaction times, and the transverse Peclet number Pe defined as the ratio between the time for diffusion across the fracture and the time for advection along the fracture. Reactant species are readily consumed near the inlet in a carbonate reservoir when the flow velocity is low (low transverse Peclet number and Da>10-1). At high flow velocities, diffusion fails to homogenize the concentration field across the fracture (high transverse Peclet number Pe>10-1). When the reaction rate is low as in anorthite reservoirs (Da<10-1) reactant species are more readily transported towards the outlet. At a given Peclet number, a lower Damköhler number causes the flow channel to experience a more uniform aperture enlargement along the length of the fracture. When the length-to-aperture ratio is sufficiently large, say l/d>30, the system response resembles the solution for 1-D reactive fluid transport. A decreased length-to-aperture ratio slows the diffusive transport of reactant species to the mineral fracture surface, and analyses of fracture networks must take into consideration both the length and slenderness of individual fractures in addition to Pe and Da numbers.

  12. Childhood trauma, psychosis liability and social stress reactivity : a virtual reality study

    NARCIS (Netherlands)

    Veling, W.; Counotte, J.; Pot-Kolder, R.; van Os, J.; van der Gaag, M.

    2016-01-01

    Background. Childhood trauma is associated with higher risk for mental disorders, including psychosis. Heightened sensitivity to social stress may be a mechanism. This virtual reality study tested the effect of childhood trauma on level of paranoid ideations and distress in response to social

  13. Childhood trauma and social stress reactivity in psychosis : A virtual reality study

    NARCIS (Netherlands)

    Veling, Wim; Counotte, Jacqueline; Pot-Kolder, Roos; Van Os, Jim; Van Der Gaag, Mark

    2016-01-01

    Introduction: Childhood trauma may be related to risk for psychosis by the mechanism of sensitization to social stress. Virtual Reality (VR) provides the opportunity to test this mechanism by controlled experimental exposure to different social environments. Methods: Fifty-five patients with recent

  14. Effects of sleep deprivation on cardiac autonomic and pituitary-adrenocortical stress reactivity in rats

    NARCIS (Netherlands)

    Sgoifo, A; Buwalda, B; Roos, M.; Costoli, T; Merati, G; Meerlo, P

    2006-01-01

    A demanding life style, often associated with restricted time for sleep, is a growing problem in our society and may become a major health issue in the near future. Since the physiological stress system plays a critical role in coping with a challenge, it is important to know whether this system is

  15. Stress susceptibility as a determinant of endothelium-dependent vascular reactivity in rat mesenteric arteries.

    NARCIS (Netherlands)

    Riksen, N.P.; Ellenbroek, B.A.; Cools, A.R.; Siero, H.L.M.; Rongen, G.A.P.J.M.; Smits, B.W.; Russel, F.G.M.; Smits, P.

    2003-01-01

    In order to investigate the consequences of stress susceptibility on vascular function, the authors assessed the respective contributions of nitric oxide (NO), prostanoids, and endothelium-derived hyperpolarizing factor to the vascular tone in rats with a constitutionally determined high and low

  16. Oxidative Stress in the Developing Rat Brain due to Production of Reactive Oxygen and Nitrogen Species

    Czech Academy of Sciences Publication Activity Database

    Wilhelm, Jiří; Vytášek, Richard; Uhlík, Jiří; Vajner, Luděk

    2016-01-01

    Roč. 2016, č. 2016 (2016), č. článku 5057610. ISSN 1942-0900 R&D Projects: GA ČR(CZ) GAP303/11/0298 Institutional support: RVO:67985823 Keywords : oxidative stress * developing rat brain * lipid peroxidation Subject RIV: ED - Physiology Impact factor: 4.593, year: 2016

  17. Sexually dimorphic effects of ancestral exposure to vinclozolin on stress reactivity in rats.

    Science.gov (United States)

    Gillette, Ross; Miller-Crews, Isaac; Nilsson, Eric E; Skinner, Michael K; Gore, Andrea C; Crews, David

    2014-10-01

    How an individual responds to the environment depends upon both personal life history as well as inherited genetic and epigenetic factors from ancestors. Using a 2-hit, 3 generations apart model, we tested how F3 descendants of rats given in utero exposure to the environmental endocrine-disrupting chemical (EDC) vinclozolin reacted to stress during adolescence in their own lives, focusing on sexually dimorphic phenotypic outcomes. In adulthood, male and female F3 vinclozolin- or vehicle-lineage rats, stressed or nonstressed, were behaviorally characterized on a battery of tests and then euthanized. Serum was used for hormone assays, and brains were used for quantitative PCR and transcriptome analyses. Results showed that the effects of ancestral exposure to vinclozolin converged with stress experienced during adolescence in a sexually dimorphic manner. Debilitating effects were seen at all levels of the phenotype, including physiology, behavior, brain metabolism, gene expression, and genome-wide transcriptome modifications in specific brain nuclei. Additionally, females were significantly more vulnerable than males to transgenerational effects of vinclozolin on anxiety but not sociality tests. This fundamental transformation occurs in a manner not predicted by the ancestral exposure or the proximate effects of stress during adolescence, an interaction we refer to as synchronicity.

  18. The influence of postnatal handling on adult neuroendocrine and behavioural stress reactivity

    NARCIS (Netherlands)

    Meerlo, P; Horvath, KM; Nagy, GM; Bohus, B; Koolhaas, JM

    1999-01-01

    Environmental stimuli during early stages of life can influence the development of an organism and may result in permanent changes in adult behaviour and physiology. In the present study we investigated the influence of early postnatal handling on adult neuroendocrine and behavioural stress

  19. Review of the Psychometric Evidence of the Perceived Stress Scale

    Directory of Open Access Journals (Sweden)

    Eun-Hyun Lee, RN, PhD

    2012-12-01

    Conclusion: Overall, the PSS is an easy-to-use questionnaire with established acceptable psychometric properties. However, future studies should evaluate these psychometric properties in greater depth, and validate the scale using diverse populations.

  20. Adaptation to Portuguese of the Depression, Anxiety and Stress Scales (DASS)

    OpenAIRE

    Apóstolo,João Luís Alves; Mendes,Aida Cruz; Azeredo,Zaida Aguiar

    2006-01-01

    Objective: to adapt to Portuguese, of Portugal, the Depression, Anxiety and Stress Scales, a 21-item short scale (DASS 21), designed to measure depression, anxiety and stress. Method: After translation and back-translation with the help of experts, the DASS 21 was administered to patients in external psychiatry consults (N=101), and its internal consistency, construct validity and concurrent validity were measured. Results: The DASS 21 properties certify its quality to measure emotional state...

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

    Science.gov (United States)

    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),…

  2. Experimental determination and theoretical analysis of local residual stress at grain scale

    NARCIS (Netherlands)

    Basu, Indranil; Ocelík, Václav; De Hosson, Jeff Th M.

    2017-01-01

    Grain/phase boundaries contribute significantly to build up of residual stresses, owing to varied plastic/thermal response of different grain orientations or phases during thermomechanical treatment. Hence, accurate quantification of such local scale stress gradients in commercial components is

  3. Effects of Metformin on Tissue Oxidative and Dicarbonyl Stress in Transgenic Spontaneously Hypertensive Rats Expressing Human C-Reactive Protein.

    Directory of Open Access Journals (Sweden)

    Hana Malínská

    Full Text Available Inflammation and oxidative and dicarbonyl stress play important roles in the pathogenesis of type 2 diabetes. Metformin is the first-line drug of choice for the treatment of type 2 diabetes because it effectively suppresses gluconeogenesis in the liver. However, its "pleiotropic" effects remain controversial. In the current study, we tested the effects of metformin on inflammation, oxidative and dicarbonyl stress in an animal model of inflammation and metabolic syndrome, using spontaneously hypertensive rats that transgenically express human C-reactive protein (SHR-CRP. We treated 8-month-old male transgenic SHR-CRP rats with metformin (5 mg/kg/day mixed as part of a standard diet for 4 weeks. A corresponding untreated control group of male transgenic SHR-CRP rats were fed a standard diet without metformin. In a similar fashion, we studied a group of nontransgenic SHR treated with metformin and an untreated group of nontransgenic SHR controls. In each group, we studied 6 animals. Parameters of glucose and lipid metabolism and oxidative and dicarbonyl stress were measured using standard methods. Gene expression profiles were determined using Affymetrix GeneChip Arrays. Statistical significance was evaluated by two-way ANOVA. In the SHR-CRP transgenic strain, we found that metformin treatment decreased circulating levels of inflammatory response marker IL-6, TNFα and MCP-1 while levels of human CRP remained unchanged. Metformin significantly reduced oxidative stress (levels of conjugated dienes and TBARS and dicarbonyl stress (levels of methylglyoxal in left ventricles, but not in kidneys. No significant effects of metformin on oxidative and dicarbonyl stress were observed in SHR controls. In addition, metformin treatment reduced adipose tissue lipolysis associated with human CRP. Possible molecular mechanisms of metformin action-studied by gene expression profiling in the liver-revealed deregulated genes from inflammatory and insulin signaling

  4. Blood pressure reactivity to psychological stress and coronary calcification in the Coronary Artery Risk Development in Young Adults Study.

    Science.gov (United States)

    Matthews, Karen A; Zhu, Sha; Tucker, Diane C; Whooley, Mary A

    2006-03-01

    A longstanding hypothesis is that individuals who exhibit large increases in blood pressure during psychological stress are at risk for atherosclerosis. We tested whether blood pressure changes during psychological stress predict subsequent coronary calcification (CaC) in young healthy adults. We evaluated 2816 healthy black and white women, 20 to 35 years of age, from the Coronary Artery Risk Development in Young Adults Study, who were not using medication for hypertension or diabetes in 1987-1988. Participants completed video game and star tracing tasks while their blood pressure was recorded. Thirteen years later (2000-2001), they completed computed tomography measures of CaC. Overall 9.3% (261 of 2816) had CaC present at follow-up. Each 10 mm Hg change in systolic blood pressure during the video game was associated with a 24% increased odds of having CaC at follow-up (unadjusted odds ratio, 1.24; 95% CI, 1.06 to 1.46; P=0.008). This association persisted after adjustment for age, race, sex, education, smoking, alcohol, family history of myocardial infarction, smoking, daily alcohol consumption, body mass index, and resting or baseline blood pressure (odds ratio, 1.31; 95% CI, 1.08 to 1.58; P=0.006). Blood pressure changes during the star tracing task were not associated with subsequent CaC. Blood pressure changes during a video game predicted the presence of CaC 13 years later. To our knowledge, this is the first study that reports blood pressure reactivity to a stressor being related to calcification in the coronary arteries. Blood pressure reactivity may provide useful prognostic information about future risk beyond standard risk factors.

  5. Pore scale study of multiphase multicomponent reactive transport during CO2 dissolution trapping

    Science.gov (United States)

    Chen, Li; Wang, Mengyi; Kang, Qinjun; Tao, Wenquan

    2018-06-01

    Solubility trapping is crucial for permanent CO2 sequestration in deep saline aquifers. For the first time, a pore-scale numerical method is developed to investigate coupled scCO2-water two-phase flow, multicomponent (CO2(aq), H+, HCO3-, CO32- and OH-) mass transport, heterogeneous interfacial dissolution reaction, and homogeneous dissociation reactions. Pore-scale details of evolutions of multiphase distributions and concentration fields are presented and discussed. Time evolutions of several variables including averaged CO2(aq) concentration, scCO2 saturation, and pH value are analyzed. Specific interfacial length, an important variable which cannot be determined but is required by continuum models, is investigated in detail. Mass transport coefficient or efficient dissolution rate is also evaluated. The pore-scale results show strong non-equilibrium characteristics during solubility trapping due to non-uniform distributions of multiphase as well as slow mass transport process. Complicated coupling mechanisms between multiphase flow, mass transport and chemical reactions are also revealed. Finally, effects of wettability are also studied. The pore-scale studies provide deep understanding of non-linear non-equilibrium multiple physicochemical processes during CO2 solubility trapping processes, and also allow to quantitatively predict some important empirical relationships, such as saturation-interfacial surface area, for continuum models.

  6. Long-Term Effects of Neonatal Pain and Stress on Reactivity of the Nociceptive System.

    Science.gov (United States)

    Butkevich, I P; Mikhailenko, V A

    2016-10-01

    The influence of inflammatory pain and/or weaning stress at different terms of neonatal development on functional activity of the nociceptive system during adulthood was studied in rats. Repeated stress in 1-2-day-old rat pups (a premature baby model) enhanced pain sensitivity to peripheral inflammation in both males and females. Repeated inflammatory pain experienced by male pups aged 1-2 or 7-8 days (models of preterm and full-term baby), even in presence of mother, enhanced pain behavior under conditions of repeated inflammatory pain in adulthood. Pain sensitivity in adult animals before (hot plate test) and after formation of the inflammatory focus (formalin test) depended on the age when the animals were subjected to the injury, type of exposure, and on animal sex. The priority data obtained by us will help to understand the mechanisms of long-term effects of early injuries and are important for pediatricians and neonatologists.

  7. Reactive distillation : The front-runner of industrial process intensification - A full review of commercial applications, research, scale-up, design and operation

    NARCIS (Netherlands)

    Harmsen, G. Jan

    Most industrial scale reactive distillations (presently more than 150), operated worldwide today at capacities of 100-3000 ktonnes/y, and are reported in this paper. Most of these plants started up less than 15 years ago. The drivers, processes, systems, scale-up methods and partner collaborations

  8. Increased reactive oxygen species levels cause ER stress and cytotoxicity in andrographolide treated colon cancer cells.

    Science.gov (United States)

    Banerjee, Aditi; Banerjee, Vivekjyoti; Czinn, Steven; Blanchard, Thomas

    2017-04-18

    Chemotherapy continues to play an essential role in the management of many cancers including colon cancer, the third leading cause of death due to cancer in the United States. Many naturally occurring plant compounds have been demonstrated to possess anti-cancer cell activity and have the potential to supplement existing chemotherapy strategies. The plant metabolite andrographolide induces cell death in cancer cells and apoptosis is dependent upon the induction of endoplasmic reticulum stress (ER stress) leading to the unfolded protein response (UPR). The goal of the present study was to determine the mechanism by which andrographolide induces ER stress and to further evaluate its role in promoting cell death pathways. The T84 and COLO 205 cancer cell lines were used to demonstrate that andrographolide induces increased ROS levels, corresponding anti-oxidant response molecules, and reduced mitochondrial membrane potential. No increases in ROS levels were detected in control colon fibroblast cells. Andrographolide-induced cell death, UPR signaling, and CHOP, Bax, and caspase 3 apoptosis elements were all inhibited in the presence of the ROS scavenger NAC. Additionally, andrographolide-induced suppression of cyclins B1 and D1 were also reversed in the presence of NAC. Finally, Akt phosphorylation and phospho-mTOR levels that are normally suppressed by andrographolide were also expressed at normal levels in the absence of ROS. These data demonstrate that andrographolide induces ER stress leading to apoptosis through the induction of ROS and that elevated ROS also play an important role in down-regulating cell cycle progression and cell survival pathways as well.

  9. Adolescent habitual caffeine consumption and hemodynamic reactivity during rest, psychosocial stress, and recovery.

    Science.gov (United States)

    James, Jack E; Baldursdottir, Birna; Johannsdottir, Kamilla R; Valdimarsdottir, Heiddis B; Sigfusdottir, Inga Dora

    2018-07-01

    Most adolescents regularly consume caffeine. Whereas observational studies have suggested that coffee may be cardio-protective, pharmacological experimentation with adults shows that caffeine at dietary doses increases blood pressure, thereby implicating regular caffeine consumption as a potential source of harm for cardiovascular health. The present study was in response to the dearth of caffeine research among younger consumers. It was hypothesised that compared to the consumption of little or no caffeine, adolescents who habitually consume caffeine have overall higher blood pressure and increased vascular resistance. Using a quasi-experimental design, continuous measurements of blood pressure, cardiac output, and total peripheral resistance were taken non-invasively from adolescents (n = 333) aged 14-15 years and 18-19 years who reported "low", "moderate", or "high" levels of caffeine intake. Measurements were conducted when participants generally had negligible or low systematic caffeine levels while at rest, during stress, and during recovery from stress. Whereas habitual caffeine consumption did not predict blood pressure level, higher caffeine intake was associated with modestly increased vascular resistance during all phases of the experiment (i.e., at rest, during stress, and during recovery from stress). Present findings are important because they suggest that early exposure to caffeine may lead to persistent increases in vascular resistance, which in turn is an acknowledged risk factor for the development of hypertension. These results highlight the need for further studies of adolescents to determine the robustness of any persistent caffeine-related hemodynamic effects, and the implications such effects could have for long-term cardiovascular health. Copyright © 2018 Elsevier Inc. All rights reserved.

  10. Sexually Dimorphic Effects of Ancestral Exposure to Vinclozolin on Stress Reactivity in Rats

    OpenAIRE

    Gillette, Ross; Miller-Crews, Isaac; Nilsson, Eric E.; Skinner, Michael K.; Gore, Andrea C.; Crews, David

    2014-01-01

    How an individual responds to the environment depends upon both personal life history as well as inherited genetic and epigenetic factors from ancestors. Using a 2-hit, 3 generations apart model, we tested how F3 descendants of rats given in utero exposure to the environmental endocrine-disrupting chemical (EDC) vinclozolin reacted to stress during adolescence in their own lives, focusing on sexually dimorphic phenotypic outcomes. In adulthood, male and female F3 vinclozolin- or vehicle-linea...

  11. Self-reported racial discrimination and endothelial reactivity to acute stress in women.

    Science.gov (United States)

    Wagner, Julie A; Tennen, Howard; Finan, Patrick H; Ghuman, Nimrta; Burg, Matthew M

    2013-08-01

    This study investigated the effect of self-reported racial discrimination on endothelial responses to acute laboratory mental stress among post-menopausal women. One-hundred thirteen women (n = 94 self-identified as White and n = 19 self-identified as racial/ethnic minority), 43% with type 2 diabetes, reported lifetime experiences of racial/ethnic discrimination. Repeated assessments of flow-mediated dilation were performed at baseline, immediately after 5 min of mental arithmetic and at 20-min recovery. Both White and racial/ethnic minority women reported lifetime discrimination, with rates significantly higher among minorities. Self-reported lifetime discrimination was associated with attenuated flow-mediated dilation at recovery. Confounding variables, including clinical characteristics, mood, personality traits, other life stressors and general distress, did not better account for the effect of racial discrimination. Neither race/ethnicity nor diabetes status moderated the effect. The perceived stressfulness of the mental arithmetic was not associated with the endothelial response. In conclusion, self-reported lifetime discrimination is associated with attenuated endothelial recovery from acute mental stress. Elucidating the effects of discrimination and the biological mechanisms through which it affects the vasculature may suggest interventions to improve health. Copyright © 2012 John Wiley & Sons, Ltd.

  12. Blood pressure reactivity to psychological stress predicts hypertension in the CARDIA study.

    Science.gov (United States)

    Matthews, Karen A; Katholi, Charles R; McCreath, Heather; Whooley, Mary A; Williams, David R; Zhu, Sha; Markovitz, Jerry H

    2004-07-06

    A longstanding but controversial hypothesis is that individuals who exhibit frequent, large increases in blood pressure (BP) during psychological stress are at risk for developing essential hypertension. We tested whether BP changes during psychological stress predict incident hypertension in young adults. We used survival analysis to predict hypertensive status during 13 years of follow-up in a sample of >4100 normotensive black and white men and women (age at entry, 18 to 30 years) enrolled in the CARDIA study. BP responses to 3 psychological challenges--cold pressor, star tracing, and video game tasks--were measured. Hypertensive status was defined as use of antihypertensive medication or measured BP > or =140/90 mm Hg. After adjustment for race, gender, covariates (education, body mass index, age, and resting pressure), and their significant interactions, the larger the BP responses were to each of the 3 tasks, the earlier hypertension occurred (Pvideo game was apparent for men. Young adults who show a large BP response to psychological stress may be at risk for hypertension as they approach midlife.

  13. A Novel Nano/Micro-Fluidic Reactor for Evaluation of Pore-Scale Reactive Transport

    Science.gov (United States)

    Werth, C. J.; Alcalde, R.; Ghazvini, S.; Sanford, R. A.; Fouke, B. W.; Valocchi, A. J.

    2017-12-01

    The reactive transport of pollutants in groundwater can be affected by the presence of stressor chemicals, which inhibit microbial functions. The stressor can be a primary reactant (e.g., trichloroethene), a reaction product (e.g., nitrite from nitrate), or some other chemical present in groundwater (e.g., antibiotic). In this work, a novel nano/microfluidic cell was developed to examine the effect of the antibiotic ciprofloxacin on nitrate reduction coupled to lactate oxidation. The reactor contains parallel boundary channels that deliver flow and solutes on either side of a pore network. The boundary channels are separated from the pore network by one centimeter-long, one micrometer-thick walls perforated by hundreds of nanoslits. The nanoslits allow solute mass transfer from the boundary channels to the pore network, but not microbial passage. The pore network was inoculated with a pure culture of Shewanella oneidensis MR-1, and this was allowed to grow on lactate and nitrate in the presence of ciprofloxacin, all delivered through the boundary channels. Microbial growth patterns suggest inhibition from ciprofloxacin and the nitrate reduction product nitrite, and a dependence on nitrate and lactate mass transfer rates from the boundary channels. A numerical model was developed to interpret the controlling mechanisms, and results indicate cell chemotaxis also affects nitrate reduction and microbial growth. The results are broadly relevant to bioremediation efforts where one or more chemicals that inhibit microbial growth are present and inhibit pollutant degradation rates.

  14. Size-scaling of tensile failure stress in boron carbide

    Energy Technology Data Exchange (ETDEWEB)

    Wereszczak, Andrew A [ORNL; Kirkland, Timothy Philip [ORNL; Strong, Kevin T [ORNL; Jadaan, Osama M. [University of Wisconsin, Platteville; Thompson, G. A. [U.S. Army Dental and Trauma Research Detachment, Greak Lakes

    2010-01-01

    Weibull strength-size-scaling in a rotary-ground, hot-pressed boron carbide is described when strength test coupons sampled effective areas from the very small (~ 0.001 square millimeters) to the very large (~ 40,000 square millimeters). Equibiaxial flexure and Hertzian testing were used for the strength testing. Characteristic strengths for several different specimen geometries are analyzed as a function of effective area. Characteristic strength was found to substantially increase with decreased effective area, and exhibited a bilinear relationship. Machining damage limited strength as measured with equibiaxial flexure testing for effective areas greater than ~ 1 mm2 and microstructural-scale flaws limited strength for effective areas less than 0.1 mm2 for the Hertzian testing. The selections of a ceramic strength to account for ballistically-induced tile deflection and to account for expanding cavity modeling are considered in context with the measured strength-size-scaling.

  15. Large Amounts of Reactivated Virus in Tears Precedes Recurrent Herpes Stromal Keratitis in Stressed Rabbits Latently Infected with Herpes Simplex Virus.

    Science.gov (United States)

    Perng, Guey-Chuen; Osorio, Nelson; Jiang, Xianzhi; Geertsema, Roger; Hsiang, Chinhui; Brown, Don; BenMohamed, Lbachir; Wechsler, Steven L

    2016-01-01

    Recurrent herpetic stromal keratitis (rHSK), due to an immune response to reactivation of herpes simplex virus (HSV-1), can cause corneal blindness. The development of therapeutic interventions such as drugs and vaccines to decrease rHSK have been hampered by the lack of a small and reliable animal model in which rHSK occurs at a high frequency during HSV-1 latency. The aim of this study is to develop a rabbit model of rHSK in which stress from elevated temperatures increases the frequency of HSV-1 reactivations and rHSK. Rabbits latently infected with HSV-1 were subjected to elevated temperatures and the frequency of viral reactivations and rHSK were determined. In an experiment in which rabbits latently infected with HSV-1 were subjected to ill-defined stress as a result of failure of the vivarium air conditioning system, reactivation of HSV-1 occurred at over twice the normal frequency. In addition, 60% of eyes developed severe rHSK compared to tears of that eye and whenever this unusually large amount of reactivated virus was detected in tears, rHSK always appeared 4-5 days later. In subsequent experiments using well defined heat stress the reactivation frequency was similarly increased, but no eyes developed rHSK. The results reported here support the hypothesis that rHSK is associated not simply with elevated reactivation frequency, but rather with rare episodes of very high levels of reactivated virus in tears 4-5 days earlier.

  16. Using the reactive scope model to understand why stress physiology predicts survival during starvation in Galápagos marine iguanas.

    Science.gov (United States)

    Romero, L Michael

    2012-05-01

    Even though the term "stress" is widely used, a precise definition is notoriously difficult. Notwithstanding this difficulty, stress continues to be an important concept in biology because it attempts to describe how animals cope with environmental change under emergency conditions. Without a precise definition, however, it becomes nearly impossible to make testable a priori predictions about how physiological and hormonal systems will respond to emergency conditions and what the ultimate impact on the animal will be. The reactive scope model is a recent attempt to formulate testable predictions. This model provides a physiological basis to explain why corticosterone negative feedback, but not baseline corticosterone concentrations, corticosterone responses to acute stress, or the interrenal capacity to secrete corticosterone, is correlated with survival during famine conditions in Galápagos marine iguanas. Reactive scope thus provides a foundation for interpreting and predicting physiological stress responses. Copyright © 2011 Elsevier Inc. All rights reserved.

  17. Modeling the Residual Stresses in Reactive Resins-Based Materials: a Case Study of Photo-Sensitive Composites for Dental Applications

    International Nuclear Information System (INIS)

    Grassia, Luigi; D'Amore, Alberto

    2010-01-01

    Residual stresses in reactive resins-based composites are associated to the net volumetric contraction (shrinkage) arising during the cross-linking reactions. Depending on the restoration geometry (the ratio of the free surface area to the volume of the cavity) the frozen-in stresses can be as high as the strength of the dental composites. This is the main reason why the effectiveness and then the durability of restorations with composites remains quite lower than those realized with metal alloys based materials. In this paper we first explore the possibility to circumvent the mathematical complexity arising from the determination of residual stresses in reactive systems three-dimensionally constrained. Then, the results of our modeling approach are applied to a series of commercially available composites showing that almost all samples develop residual stresses such that the restoration undergoes failure as soon as it is realized.

  18. Lack of Reactive Oxygen Species Deteriorates Blood Pressure Regulation in Acute Stress

    Czech Academy of Sciences Publication Activity Database

    Bernátová, I.; Bališ, P.; Goga, R.; Behuliak, Michal; Zicha, Josef; Sekaj, I.

    2016-01-01

    Roč. 65, Suppl.3 (2016), S381-S390 ISSN 0862-8408 R&D Projects: GA MZd(CZ) NV15-25396A Grant - others:AV ČR(CZ) SAV-16-18 Program:Bilaterální spolupráce Institutional support: RVO:67985823 Keywords : air-jet stress * superoxide * nitric oxide * sympathetic nervous system * renin-angiotensin system Subject RIV: FA - Cardiovascular Diseases incl. Cardiotharic Surgery Impact factor: 1.461, year: 2016

  19. The Depression Anxiety and Stress Scale (DASS): The Study of Validity and Reliability

    Science.gov (United States)

    Akin, Ahmet; Cetin, Bayram

    2007-01-01

    This study investigated the validity and reliability of the Turkish version of the Depression Anxiety Stress Scale (DASS). The sample of the study consisted of 590 university students, 121 English teachers and 136 emotionally disturbed individuals who sought treatment in various clinics and counseling centers. Factor loadings of the scale ranged…

  20. Achillolide A Protects Astrocytes against Oxidative Stress by Reducing Intracellular Reactive Oxygen Species and Interfering with Cell Signaling

    Directory of Open Access Journals (Sweden)

    Anat Elmann

    2016-03-01

    Full Text Available Achillolide A is a natural sesquiterpene lactone that we have previously shown can inhibit microglial activation. In this study we present evidence for its beneficial effects on astrocytes under oxidative stress, a situation relevant to neurodegenerative diseases and brain injuries. Viability of brain astrocytes (primary cultures was determined by lactate dehydrogenase (LDH activity, intracellular ROS levels were detected using 2′,7′-dichlorofluorescein diacetate, in vitro antioxidant activity was measured by differential pulse voltammetry, and protein phosphorylation was determined using specific ELISA kits. We have found that achillolide A prevented the H2O2-induced death of astrocytes, and attenuated the induced intracellular accumulation of reactive oxygen species (ROS. These activities could be attributed to the inhibition of the H2O2-induced phosphorylation of MAP/ERK kinase 1 (MEK1 and p44/42 mitogen-activated protein kinases (MAPK, and to the antioxidant activity of achillolide A, but not to H2O2 scavenging. This is the first study that demonstrates its protective effects on brain astrocytes, and its ability to interfere with MAPK activation. We propose that achillolide A deserves further evaluation for its potential to be developed as a drug for the prevention/treatment of neurodegenerative diseases and brain injuries where oxidative stress is part of the pathophysiology.

  1. The anticipatory stress response to sport competition; a systematic review with meta-analysis of cortisol reactivity.

    Science.gov (United States)

    van Paridon, Kjell N; Timmis, Matthew A; Nevison, Charlotte M; Bristow, Matt

    2017-01-01

    Athletes anticipating sport competition regularly experience distinct emotional and physiological responses as a result of the expected psychosocial and physical stress. Specifically, cortisol, an indicator of hypothalamic-pituitary-adrenal axis activation, prepares the athlete for the psychological and physiological demands of competition. The objective of this meta-analysis is to analyse the magnitude of the anticipatory cortisol response in athletes preparing to participate in sport competition and to examine the influence of gender, level of competition and data collection time. Systematic review with meta-analysis. Four electronic databases were searched to March 2017: PubMed, PsycINFO, SPORTDiscus and Scopus. (1) Athletes participating in real sport competition;(2) salivary cortisol concentration collected before competition in addition to baseline sample(s);(3) original research article published in English language. Data from 25 studies provided 27 effect sizes. A significant anticipatory cortisol response of g=0.85, pstress response. There were no significant differences between level of competition, type of sport or time of competition. Meta-regression indicated that the anticipatory cortisol response is greater when assessed closer to the start of competition (Q=6.85, p=0.009). The anticipatory cortisol response before sport competition reflects moderate cortisol reactivity that prepares athletes optimally for the demands of sport competition via the influence on cognitive processes and attentional control. However, both female athletes and international competitors did not demonstrate a significant anticipatory cortisol response, possibly due to differences in appraisal of the stress of sport competition.

  2. Social modulation of stress reactivity and learning in young worker honey bees.

    Directory of Open Access Journals (Sweden)

    Elodie Urlacher

    Full Text Available Alarm pheromone and its major component isopentylacetate induce stress-like responses in forager honey bees, impairing their ability to associate odors with a food reward. We investigated whether isopentylacetate exposure decreases appetitive learning also in young worker bees. While isopentylacetate-induced learning deficits were observed in guards and foragers collected from a queen-right colony, learning impairments resulting from exposure to this pheromone could not be detected in bees cleaning cells. As cell cleaners are generally among the youngest workers in the colony, effects of isopentylacetate on learning behavior were examined further using bees of known age. Adult workers were maintained under laboratory conditions from the time of adult emergence. Fifty percent of the bees were exposed to queen mandibular pheromone during this period, whereas control bees were not exposed to this pheromone. Isopentylacetate-induced learning impairments were apparent in young (less than one week old controls, but not in bees of the same age exposed to queen mandibular pheromone. This study reveals young worker bees can exhibit a stress-like response to alarm pheromone, but isopentylacetate-induced learning impairments in young bees are suppressed by queen mandibular pheromone. While isopentylacetate exposure reduced responses during associative learning (acquisition, it did not affect one-hour memory retrieval.

  3. HPA-axis stress reactivity in youth depression: evidence of impaired regulatory processes in depressed boys.

    Science.gov (United States)

    Lopez-Duran, Nestor L; McGinnis, Ellen; Kuhlman, Kate; Geiss, Elisa; Vargas, Ivan; Mayer, Stefanie

    2015-01-01

    Given the link between youth depression and stress exposure, efforts to identify related biomarkers have involved examinations of stress regulation systems, including the hypothalamic-pituitary-adrenal (HPA) axis. Despite these vast efforts, the underlying mechanisms at play, as well as factors that may explain heterogeneity of past findings, are not well understood. In this study, we simultaneously examined separate components of the HPA-axis response (e.g. activation intensity, peak levels, recovery) to the Socially Evaluated Cold-Pressor Test in a targeted sample of 115 youth (age 9-16), recruited to overrepresent youth with elevated symptoms of depression. Among youth who displayed a cortisol response to the task, depression symptoms were associated with higher peak responses but not greater rate of activation or recovery in boys only. Among those who did not respond to the task, depression symptoms were associated with greater cortisol levels throughout the visit in boys and girls. Results suggest that depression symptoms are associated with a more prolonged activation of the axis and impaired recovery to psychosocial stressors primarily in boys. We discussed two potential mechanistic explanations of the link between depression symptoms and the duration of activation: (1) inhibitory shift (i.e. point at which the ratio of inhibitory and excitatory input into the axis shifts from greater excitatory to greater inhibitory input) or (2) inhibitory threshold (i.e. level of cortisol exposure required to activate the axis' feedback inhibition system).

  4. Lower stress-reactive cortisol in female veterans associated with military status but not PTSD.

    Science.gov (United States)

    Pierce, Meghan E; Pritchard, Laurel M

    2016-09-01

    Female veterans are a growing yet understudied population. Currently, 14.6% of all troops deployed to Afghanistan and Iraq are female. Military service is associated with an increased risk for trauma exposure and subsequent development of posttraumatic stress disorder (PTSD). Dysregulation of the hypothalamic-pituitary-adrenal axis is frequently associated with PTSD. Few studies have examined females diagnosed with PTSD and only one study, to our knowledge, has examined HPA-axis dysregulation in female veterans. This study examined salivary cortisol in 52 female veterans and civilians both with and without PTSD. We collected saliva samples at bedtime and awakening, as well as in response to the Trier social stress test (TSST). We found that female veterans had blunted cortisol concentrations at all time points during the TSST compared to female civilians, regardless of PTSD status. Even though all groups showed the expected diurnal decline in cortisol, the difference between awakening and bedtime samples were significant only in civilians without PTSD. The results of our study suggest that stressors specific to the military may lead to lower than normal cortisol, which may not be associated with the expressions of PTSD.

  5. Social Modulation of Stress Reactivity and Learning in Young Worker Honey Bees

    Science.gov (United States)

    Mercer, Alison R.

    2014-01-01

    Alarm pheromone and its major component isopentylacetate induce stress-like responses in forager honey bees, impairing their ability to associate odors with a food reward. We investigated whether isopentylacetate exposure decreases appetitive learning also in young worker bees. While isopentylacetate-induced learning deficits were observed in guards and foragers collected from a queen-right colony, learning impairments resulting from exposure to this pheromone could not be detected in bees cleaning cells. As cell cleaners are generally among the youngest workers in the colony, effects of isopentylacetate on learning behavior were examined further using bees of known age. Adult workers were maintained under laboratory conditions from the time of adult emergence. Fifty percent of the bees were exposed to queen mandibular pheromone during this period, whereas control bees were not exposed to this pheromone. Isopentylacetate-induced learning impairments were apparent in young (less than one week old) controls, but not in bees of the same age exposed to queen mandibular pheromone. This study reveals young worker bees can exhibit a stress-like response to alarm pheromone, but isopentylacetate-induced learning impairments in young bees are suppressed by queen mandibular pheromone. While isopentylacetate exposure reduced responses during associative learning (acquisition), it did not affect one-hour memory retrieval. PMID:25470128

  6. Transfer of reactive solutes in the unsaturated zone of soils at several observation scales

    International Nuclear Information System (INIS)

    Limousin, G.

    2006-10-01

    The transfer of contaminants in the unsaturated zone of soils is driven by numerous mechanisms. Field studies are sometimes difficult to set up, and so the question is raised about the reliability of laboratory measurements for describing a field situation. The nuclear power plant at Brennilis (Finistere, France) has been chosen to study the transfer of strontium, cobalt and inert tracers in the soil of this industrial site. Several observation scales have been tested (batch, stirred flow-through reactor, sieved-soil column, un-repacked or repacked soil-core lysimeter, field experiments) in order to determine, at each scale, the factors that influence the transfer of these contaminants, then to verify the adequacy between the different observation scales and their field representativeness. Regarding the soil hydrodynamic properties, the porosity, the water content in the field, the pore water velocity at the water content in the field, the saturation hydraulic conductivity and the dispersion coefficient of this embanked soil are spatially less heterogeneous than those of agricultural or non-anthropic soils. The results obtained with lysimeter and field experiments suggest that hydrodynamics of this unstructured soil can be studied on a repacked sample if the volume is high compared to the rare big-size stones. Regarding the chemical soil-contaminant interactions, cobalt and strontium isotherms are non-linear at concentration higher than 10 -4 mol.L -1 , cobalt adsorption and desorption are fast and independent on pH. On the contrary, at concentration lower than 3.5 x 10 -6 mol.L -1 , cobalt and strontium isotherms are linear, cobalt desorption is markedly slower than adsorption and both cobalt partition coefficient at equilibrium and its reaction kinetics are highly pH-dependent. For both elements, the results obtained with batch, stirred flow-through reactor and sieved-soil column are in adequacy. However, strontium batch adsorption measurements at equilibrium do

  7. Stress- and temperature-dependent scaling behavior of dynamic hysteresis in soft PZT bulk ceramics

    International Nuclear Information System (INIS)

    Yimnirun, R; Wongsaenmai, S; Wongmaneerung, R; Wongdamnern, N; Ngamjarurojana, A; Ananta, S; Laosiritaworn, Y

    2007-01-01

    Effects of electric field-frequency, electric field-amplitude, mechanical stress, and temperature on the hysteresis area, especially the scaling form, were investigated in soft lead zirconate titanate (PZT) bulk ceramics. The hysteresis area was found to depend on the frequency and field-amplitude with the same set of exponents as the power-law scaling for both with and without stresses. The inclusion of stresses into the power-law was obtained in the form of σ=0 > ∝ f -0.25 E 0 σ 0.45 which indicates the difference in energy dissipation between the under-stress and stress-free conditions. The power-law temperature scaling relations were obtained for hysteresis area (A) and remanent polarization P r , while the coercivity E C was found to scale linearly with temperature T. The three temperature scaling relations were also field-dependent. At fixed field amplitude E 0 , the scaling relations take the forms of ∝ T -1.1024 , P r ∼T -1.2322 and (E C0 - E C ) ∼T

  8. Diminished heart rate reactivity to acute psychological stress is associated with enhanced carotid intima-media thickness through adverse health behaviors.

    Science.gov (United States)

    Ginty, Annie T; Williams, Sarah E; Jones, Alexander; Roseboom, Tessa J; Phillips, Anna C; Painter, Rebecca C; Carroll, Douglas; de Rooij, Susanne R

    2016-06-01

    Recent evidence demonstrates that individuals with low heart rate (HR) reactions to acute psychological stress are more likely to be obese or smokers. Smoking and obesity are established risk factors for increased carotid intima-media thickness (IMT). The aim of this study was to examine the potential pathways linking intima-media thickness, smoking, body mass index (BMI), and HR stress reactivity. A total of 552 participants, 47.6% male, M (SD) age = 58.3 (0.94) years, were exposed to three psychological stress tasks (Stroop, mirror drawing, and speech) preceded by a resting baseline period; HR was recorded throughout. HR reactivity was calculated as the average response across the three tasks minus average baseline HR. Smoking status, BMI, and IMT were determined by trained personnel. Controlling for important covariates (e.g., socioeconomic status), structural equation modeling revealed that BMI and smoking mediated the negative relationship between HR reactivity and IMT. The hypothesized model demonstrated a good overall fit to the data, χ(2) (8) = 0.692, p = .403; CFI = 1.00; TLI = 1.00 SRMR = .01; RMSEA stress reactivity appears to be a marker for enlarged IMT and appears to be exerting its impact through already established risks. Future research should examine this relationship longitudinally and aim to intervene early. © 2016 Society for Psychophysiological Research.

  9. Determining Factors for Stress Perception Assessed with the Perceived Stress Scale (PSS-4) in Spanish and Other European Samples.

    Science.gov (United States)

    Vallejo, Miguel A; Vallejo-Slocker, Laura; Fernández-Abascal, Enrique G; Mañanes, Guillermo

    2018-01-01

    Objective: Stress perception depends on cultural and social aspects that vary from one country to another. One of the most widely disseminated methods of assessing psychological stress is the Perceived Stress Scale (PSS-4). Therefore, in order to identify these factors and their impact on mental health, the present study compares the PSS-4 results among three European countries (Great Britain, France and Spain). This study focuses on PSS-4 results within a Spanish sample to determine: (1) normative data, reliability and validity of PSS-4 in a Spanish sample and (2) how stress perception changes depending on cultural and social factors. Methods: The data were obtained from a website representing a service of a smoking cessation program, the study represented a service that was open to all individuals. The number of participants were 37,451. They reported their age, gender, nationality, marital status, education and employment status, and completed two psychological questionnaires (PPS-4 and the anxiety and depression scales of the Symptom Checklist-90-Revised, SCL 90-R). Results: The PSS-4 scores could differentiate between relevant sociodemographic variables (such as sex, age, nationality, marital status, education, parental status, employment status, and income class). The PSS-4 scores showed a positive correlation with the SCL 90-R anxiety and depression scales. The normed values for interpreting the PSS-4 scores are presented. The PSS-4 showed adequate internal consistency and reliability. Conclusions: The PSS-4 is a useful instrument for assessing stress perception levels in the general population in different countries. Its internal consistency is sufficient for a 4-item scale.

  10. Determining Factors for Stress Perception Assessed with the Perceived Stress Scale (PSS-4 in Spanish and Other European Samples

    Directory of Open Access Journals (Sweden)

    Miguel A. Vallejo

    2018-01-01

    Full Text Available Objective: Stress perception depends on cultural and social aspects that vary from one country to another. One of the most widely disseminated methods of assessing psychological stress is the Perceived Stress Scale (PSS-4. Therefore, in order to identify these factors and their impact on mental health, the present study compares the PSS-4 results among three European countries (Great Britain, France and Spain. This study focuses on PSS-4 results within a Spanish sample to determine: (1 normative data, reliability and validity of PSS-4 in a Spanish sample and (2 how stress perception changes depending on cultural and social factors.Methods: The data were obtained from a website representing a service of a smoking cessation program, the study represented a service that was open to all individuals. The number of participants were 37,451. They reported their age, gender, nationality, marital status, education and employment status, and completed two psychological questionnaires (PPS-4 and the anxiety and depression scales of the Symptom Checklist-90-Revised, SCL 90-R.Results: The PSS-4 scores could differentiate between relevant sociodemographic variables (such as sex, age, nationality, marital status, education, parental status, employment status, and income class. The PSS-4 scores showed a positive correlation with the SCL 90-R anxiety and depression scales. The normed values for interpreting the PSS-4 scores are presented. The PSS-4 showed adequate internal consistency and reliability.Conclusions: The PSS-4 is a useful instrument for assessing stress perception levels in the general population in different countries. Its internal consistency is sufficient for a 4-item scale.

  11. Differential Response to Heat Stress in Outer and Inner Onion Bulb Scales.

    Science.gov (United States)

    Galsurker, Ortal; Doron-Faigenboim, Adi; Teper-Bamnolker, Paula; Daus, Avinoam; Lers, Amnon; Eshel, Dani

    2018-05-18

    Brown protective skin formation in onion bulbs can be induced by rapid postharvest heat treatment. Onions that were peeled to different depths and were exposed to heat stress showed that only the outer scale formed dry brown skin, whereas the inner scales maintained high water content and did not change color. Our results reveal that browning of the outer scale during heat treatment is due to an enzymatic process that is associated with high levels of oxidation components, such as peroxidase and quercetin glucoside. De-novo transcriptome analysis revealed differential molecular responses of the outer and inner scales to the heat stress. Genes involved in lipid metabolism, oxidation pathways and cell-wall modification were highly expressed in the outer scale during heating. Defense-response-related genes such as those encoding heat-shock proteins, antioxidative stress defense or production of osmoprotectant metabolites were mostly induced in the inner scale in response to the heat exposure. These transcriptomic data led to a conceptual model that suggests sequential processes for browning development and desiccation of the outer scales versus processes associated with defense response and heat tolerance in the inner scale. Thus, the observed physiological differences between the outer and inner scales is supported by the identified molecular differences.

  12. A large-scale perspective on stress-induced alterations in resting-state networks

    Science.gov (United States)

    Maron-Katz, Adi; Vaisvaser, Sharon; Lin, Tamar; Hendler, Talma; Shamir, Ron

    2016-02-01

    Stress is known to induce large-scale neural modulations. However, its neural effect once the stressor is removed and how it relates to subjective experience are not fully understood. Here we used a statistically sound data-driven approach to investigate alterations in large-scale resting-state functional connectivity (rsFC) induced by acute social stress. We compared rsfMRI profiles of 57 healthy male subjects before and after stress induction. Using a parcellation-based univariate statistical analysis, we identified a large-scale rsFC change, involving 490 parcel-pairs. Aiming to characterize this change, we employed statistical enrichment analysis, identifying anatomic structures that were significantly interconnected by these pairs. This analysis revealed strengthening of thalamo-cortical connectivity and weakening of cross-hemispheral parieto-temporal connectivity. These alterations were further found to be associated with change in subjective stress reports. Integrating report-based information on stress sustainment 20 minutes post induction, revealed a single significant rsFC change between the right amygdala and the precuneus, which inversely correlated with the level of subjective recovery. Our study demonstrates the value of enrichment analysis for exploring large-scale network reorganization patterns, and provides new insight on stress-induced neural modulations and their relation to subjective experience.

  13. Development of the Family Stigma Stress Scale (FSSS) for Detecting Stigma Stress in Caregivers of People With Mental Illness.

    Science.gov (United States)

    Chang, Chih-Cheng; Su, Jian-An; Chang, Kun-Chia; Lin, Chung-Ying; Koschorke, Mirja; Rüsch, Nicolas; Thornicroft, Graham

    2017-01-01

    People with mental illness and their family caregivers often perceive public stigma, which may lead to stigma-related stress (or stigma stress). However, no instruments have been developed to measure this stress for family caregivers of people with mental illness. We modified an instrument that measures the stigma stress of people with mental illness (i.e., the cognitive appraisal of stigma as a stressor) and examined the psychometric properties of the scores of the newly developed instrument: the Family Stigma Stress Scale (FSSS). Primary family caregivers of people with mental illness in Southern Taiwan ( n = 300; mean age = 53.08 ± 13.80; 136 males) completed the FSSS. An exploratory factor analysis showed that the FSSS score had two factors; both factor scores had excellent internal consistency (α = .913 and .814) and adequate test-retest reliability ( r = .627 and .533; n = 197). Significant correlations between FSSS factor scores and other instruments supported its concurrent validity and the ability of the FSSS to differentiate between clinical characteristics, for example, having been previously hospitalized or not. The FSSS is a brief and effective measure of the stigma stress of family caregivers of people with mental illness.

  14. BDNF Val66Met Genotype Interacts With a History of Simulated Stress Exposure to Regulate Sensorimotor Gating and Startle Reactivity.

    Science.gov (United States)

    Notaras, Michael J; Hill, Rachel A; Gogos, Joseph A; van den Buuse, Maarten

    2017-05-01

    Reduced expression of Brain-Derived Neurotrophic Factor (BDNF) has been implicated in the pathophysiology of schizophrenia. The BDNF Val66Met polymorphism, which results in deficient activity-dependent secretion of BDNF, is associated with clinical features of schizophrenia. We investigated the effect of this polymorphism on Prepulse Inhibition (PPI), a translational model of sensorimotor gating which is disrupted in schizophrenia. We utilized humanized BDNFVal66Met (hBDNFVal66Met) mice which have been modified to carry the Val66Met polymorphism, as well as express humanized BDNF in vivo. We also studied the long-term effect of chronic corticosterone (CORT) exposure in these animals as a model of history of stress. PPI was assessed at 30ms and 100ms interstimulus intervals (ISI). Analysis of PPI at the commonly used 100ms ISI identified that, irrespective of CORT treatment, the hBDNFVal/Met genotype was associated with significantly reduced PPI. In contrast, PPI was not different between hBDNFMet/Met and hBDNFVal/Val genotype mice. At the 30ms ISI, CORT treatment selectively disrupted sensorimotor gating of hBDNFVal/Met heterozygote mice but not hBDNFVal/Val or hBDNFMet/Met mice. Analysis of startle reactivity revealed that chronic CORT reduced startle reactivity of hBDNFVal/Val male mice by 51%. However, this was independent of the effect of CORT on PPI. In summary, we provide evidence of a distinct BDNFVal66Met heterozygote-specific phenotype using the sensorimotor gating endophenotype of schizophrenia. These data have important implications for clinical studies where, if possible, the BDNFVal/Met heterozygote genotype should be distinguished from the BDNFMet/Met genotype. © The Author 2016. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  15. Elemental Zinc Is Inversely Associated with C-Reactive Protein and Oxidative Stress in Chronic Liver Disease.

    Science.gov (United States)

    Uddin, Md Giash; Hossain, Mohammad Salim; Rahman, Md Atiqur; Uddin, A H M Mazbah; Bhuiyan, Md Shafiullah

    2017-08-01

    Chronic liver disease (CLD) is associated with the destruction of liver parenchyma cell. It is the main cause of morbidity and mortality in most of the developed countries. Oxidative stress and altered levels of different trace elements in serum have been documented for different diseases including inflammation and many liver diseases. This study aims to evaluate the serum level of malondialdehyde (MDA), nitric oxide (NO), antioxidant vitamin C, C-reactive protein (CRP), and zinc (Zn) in CLD patients and to establish a correlation among the study parameters with the severity of inflammatory conditions of CLD. In this study, CLD patients and healthy volunteers were recruited. Total cholesterol and triglyceride were determined by colorimeter using enzymatic method. Serum non-enzymatic antioxidant vitamin C, reactive oxygen species nitric oxide (NO), and malondialdehyde (MDA) were determined by UV-spectrophotometric method. Trace element (Zn) levels were determined by graphite furnace atomic absorption spectroscopy. Independent sample t test and Pearson's correlation test were performed for statistical analysis using the statistical software package SPSS, Version 20. Studies showed that the MDA (p CLD patients than in control subjects. The antioxidant vitamin C (p CLD patients than in control subjects. Elemental Zn showed an inverse relationship with MDA, NO, and CRP but positively correlated with antioxidant capacity, whereas MDA showed a positive correlation with CRP level. Thus, we conclude that attenuated level of Zn and antioxidant in serum play an important role in the inflammatory status of CLD patients by elevating the concentration of MDA, NO, and CRP.

  16. Chronic variable stress and intravenous methamphetamine self-administration – role of individual differences in behavioral and physiological reactivity to novelty

    Science.gov (United States)

    Taylor, S.B.; Watterson, L.R.; Kufahl, P.R.; Nemirovsky, N.E.; Tomek, S.E.; Conrad, C.D.; Olive, M.F.

    2016-01-01

    Stress is a contributing factor to the development and maintenance of addiction in humans. However, few studies have shown that stress potentiates the rewarding and/or reinforcing effects of methamphetamine in rodent models of addiction. The present study assessed the effects of exposure to 14 days of chronic variable stress (CVS), or no stress as a control (CON), on the rewarding and reinforcing effects of methamphetamine in adult rats using the conditioned place preference (Experiment 1) and intravenous self-administration (Experiment 2) paradigms. In Experiment 2, we also assessed individual differences in open field locomotor activity, anxiety-like behavior in the elevated plus maze (EPM), and physiological responses to a novel environment as possible predictors of methamphetamine intake patterns. Exposure to CVS for 14 days did not affect overall measures of methamphetamine conditioned reward or reinforcement. However, analyses of individual differences and direct vs. indirect effects revealed that rats exhibiting high physiological reactivity and locomotor activity in the EPM and open field tests self-administered more methamphetamine and reached higher breakpoints for drug reinforcement than rats exhibiting low reactivity. In addition, CVS exposure significantly increased the proportion of rats that exhibited high reactivity, and high reactivity was significantly correlated with increased levels of methamphetamine intake. These findings suggest that individual differences in physiological and locomotor reactivity to novel environments, as well as their interactions with stress history, predict patterns of drug intake in rodent models of methamphetamine addiction. Such predictors may eventually inform future strategies for implementing individualized treatment strategies for amphetamine use disorders. PMID:27163191

  17. Ecosystem-scale trade-offs between impacts of ozone and reactive nitrogen

    Science.gov (United States)

    Rowe, Ed; Hayes, Felicity; Sawicka, Kasia; Mills, Gina; Jones, Laurence; Moldan, Filip; Sereina, Bassin; van Dijk, Netty; Evans, Chris

    2015-04-01

    Nitrogen (N) deposition stimulates plant productivity in many terrestrial ecosystems. This is clearly beneficial for production agriculture and forestry, but increased litterfall and decreased ground-level light availability reduce the suitability of habitats for many biota (Jones et al., 2014). This mechanism (Hautier et al., 2009), together with the acidifying effects of N (Stevens et al., 2010), has caused considerable biodiversity loss at global scale. Ozone, by contrast, has the effect of reducing plant production, and a simple assessment would suggest that this might mitigate the effects of N pollution. We explored the interactions between ozone and nitrogen at mechanistic level using a version of the MADOC model (Rowe et al., 2014) modified to include effects of ozone. The model was tested against data from long-term monitoring and experimental sites with a focus on nitrogen and/or ozone effects. Effects on biodiversity were assessed by coupling the MADOC model to the MultiMOVE plant species model. We used this model-chain to explore trade-offs and synergies between the impacts of nitrogen and ozone on biodiversity and ecosystem biogeochemistry. In a review of the effects of ozone on ecosystem processes, two consistent effects were found: decreased net primary production due to damage to photosynthetic mechanisms; and an increase in litter nitrogen apparently caused by interference of ozone with the retranslocation process (Mills, in prep.). Insufficient evidence was found to justify inclusion of posited interactive mechanisms such as increased ozone susceptibility with greater nitrogen supply. However, the MADOC model illustrated emergent ozone-nitrogen interactions at ecosystem scale, for example an increase in N leaching due to decreased plant demand and greater litter N content. Empirical evidence for interactive effects of nitrogen and ozone at ecosystem scale is severely lacking, but simulated results were consistent with soil and soil solution

  18. Reactive Transport at the Pore Scale with Applications to the Dissolution of Carbonate Rocks for CO2 Sequestration Operations

    Science.gov (United States)

    Boek, E.; Gray, F.; Welch, N.; Shah, S.; Crawshaw, J.

    2014-12-01

    In CO2 sequestration operations, CO2 injected into a brine aquifer dissolves in the liquid to create an acidic solution. This may result in dissolution of the mineral grains in the porous medium. Experimentally, it is hard to investigate this process at the pore scale. Therefore we develop a new hybrid particle simulation algorithm to study the dissolution of solid objects in a laminar flow field, as encountered in porous media flow situations. First, we calculate the flow field using a multi-relaxation-time lattice Boltzmann (LB) algorithm implemented on GPUs, which demonstrates a very efficient use of the GPU device and a considerable performance increase over CPU calculations. Second, using a stochastic particle approach, we solve the advection-diffusion equation for a single reactive species and dissolve solid voxels according to our reaction model. To validate our simulation, we first calculate the dissolution of a solid sphere as a function of time under quiescent conditions. We compare with the analytical solution for this problem [1] and find good agreement. Then we consider the dissolution of a solid sphere in a laminar flow field and observe a significant change in the sphericity with time due to the coupled dissolution - flow process. Second, we calculate the dissolution of a cylinder in channel flow in direct comparison with corresponding dissolution experiments. We discuss the evolution of the shape and dissolution rate. Finally, we calculate the dissolution of carbonate rock samples at the pore scale in direct comparison with micro-CT experiments. This work builds on our recent research on calculation of multi-phase flow [2], [3] and hydrodynamic dispersion and molecular propagator distributions for solute transport in homogeneous and heterogeneous porous media using LB simulations [4]. It turns out that the hybrid simulation model is a suitable tool to study reactive flow processes at the pore scale. This is of great importance for CO2 storage and

  19. Psychometric evaluation of Turkish version of the Perceived Stress Scale with Turkish college students.

    Science.gov (United States)

    Kaya, Cahit; Tansey, Timothy N; Melekoglu, Macid; Cakiroglu, Orhan; Chan, Fong

    2017-12-20

    The Turkish version of the Perceived Stress Scale (T-PSS-10) measures the extent to which situations in one's life are appraised as stressful. The purpose of this study was to evaluate the measurement structure of T-PSS-10. Two-hundred and thirty-five Turkish university students (93 men and 142 women) completed the T-PSS-10, the Patient Health Questionnaire-9 (PHQ-9), the General Anxiety Disorder 7-Item Scale (GAD-7), and the Inventory of Common Problems (ICP). Confirmatory factor analysis results indicated that a one-factor model did not fit the data, whereas a two-factor correlated model (stress related self-efficacy beliefs, stress related feelings of helplessness) provided a better fit between the model and the data. Significant moderate correlations were found for the stress-related self-efficacy beliefs and stress-related feelings of helplessness factors with depression, anxiety, academic difficulty, relationship problems and health problems. The internal consistency reliability coefficients for the stress-related self-efficacy beliefs and stress-related feelings of helplessness factors were 0.68 and 0.85, respectively. This study provided support for the reliability and validity of T-PSS-10 suggesting that it can be used as a screening instrument by health professionals working with Turkish college students.

  20. Reactive nitrogen species in mitochondria and their implications in plant energy status and hypoxic stress tolerance

    Directory of Open Access Journals (Sweden)

    Kapuganti Jagadis Gupta

    2016-03-01

    Full Text Available Hypoxic and anoxic conditions result in the energy crisis that leads to cell damage. Since mitochondria are the primary organelles for energy production, the support of these organelles in a functional state is an important task during oxygen deprivation. Plant mitochondria adapted the strategy to survive under hypoxia by keeping electron transport operative even without oxygen via the use of nitrite as a terminal electrons acceptor. The process of nitrite reduction to nitric oxide (NO in the mitochondrial electron transport chain recycles NADH and leads to a limited rate of ATP production. The produced ATP alongside with the ATP generated by fermentation supports the processes of transcription and translation required for hypoxic survival and recovery of plants. Non-symbiotic hemoglobins (called phytoglobins in plants scavenge NO and thus contribute to regeneration of NAD+ and nitrate required for the operation of anaerobic energy metabolism. This overall operation represents an important strategy of biochemical adaptation that results in the improvement of energy status and thereby in protection of plants in the conditions of hypoxic stress.

  1. The scaling of stress distribution under small scale yielding by T-scaling method and application to prediction of the temperature dependence on fracture toughness

    International Nuclear Information System (INIS)

    Ishihara, Kenichi; Hamada, Takeshi; Meshii, Toshiyuki

    2017-01-01

    In this paper, a new method for scaling the crack tip stress distribution under small scale yielding condition was proposed and named as T-scaling method. This method enables to identify the different stress distributions for materials with different tensile properties but identical load in terms of K or J. Then by assuming that the temperature dependence of a material is represented as the stress-strain relationship temperature dependence, a method to predict the fracture load at an arbitrary temperature from the already known fracture load at a reference temperature was proposed. This method combined the T-scaling method and the knowledge “fracture stress for slip induced cleavage fracture is temperature independent.” Once the fracture load is predicted, fracture toughness J c at the temperature under consideration can be evaluated by running elastic-plastic finite element analysis. Finally, the above-mentioned framework to predict the J c temperature dependency of a material in the ductile-to-brittle temperature distribution was validated for 0.55% carbon steel JIS S55C. The proposed framework seems to have a possibility to solve the problem the master curve is facing in the relatively higher temperature region, by requiring only tensile tests. (author)

  2. Stress reactivity in war-exposed young children with and without posttraumatic stress disorder: relations to maternal stress hormones, parenting, and child emotionality and regulation.

    Science.gov (United States)

    Feldman, Ruth; Vengrober, Adva; Eidelman-Rothman, Moranne; Zagoory-Sharon, Orna

    2013-11-01

    The current study examined biomarkers of stress in war-exposed young children and addressed maternal and child factors that may correlate with children's stress response. Participants were 232 Israeli children aged 1.5-5 years, including 148 children exposed to continuous war. Similarly, 56 were diagnosed with posttraumatic stress disorder (PTSD) and 92 were defined as exposed-no-PTSD. Child cortisol (CT) and salivary alpha amylase (sAA), biomarkers of the hypothalamic-pituitary-adrenal and sympathetic-adrenal-medullary arms of the stress response, were measured at baseline, following challenge, and at recovery. Maternal CT and sAA, PTSD symptoms, and reciprocal parenting, and child negative emotionality and regulatory strategies were assessed. Differences between war-exposed children and controls emerged, but these were related to child PTSD status. Children with PTSD exhibited consistently low CT and sAA, exposed-no-PTSD displayed consistently high CT and sAA, and controls showed increase in CT following challenge and decrease at recovery and low sAA. Exposed children showed higher negative emotionality; however, whereas exposed-no-PTSD children employed comfort-seeking strategies, children with PTSD used withdrawal. Predictors of child CT included maternal CT, PTSD symptoms, low reciprocity, and negative emotionality. Findings suggest that high physiological arousal combined with approach strategies may be associated with greater resilience in the context of early trauma.

  3. Investigation of independent verification and validation of the servicemen occupational stress scale

    Directory of Open Access Journals (Sweden)

    Jia XU

    2012-12-01

    Full Text Available Objective  To examine the reliability and validity of the servicemen occupational stress scale. Methods  A survey with the servicemen occupational stress scale was carried out on 1100 randomly chosen military personnel in the army, and 106 among them also underwent examination with Chinese Military Mental Health Scale (CMMHS at the same time. Results  The Cronbach's α coefficient of total scale was 0.929, and subscales were 0.731-0.857 (P<0.01; the half reliability of total scale was 0.932, and subscales were 0.465-0.881 (P<0.01. The correlation coefficients among factors and between factors and total scale score were 0.699-0.900 (P<0.01. The factors of the servicemen occupational stress scale showed a significant correlation with most factors of the CMMHS, the correlation coefficients were 0.186-0253. According to the results of exploratory factor analysis, it was showed that the scale of the entries in the collation and factors named were more reasonable. According to the results of confirmatory factor analysis, there was a higher degree of accordance between the sample data and the hypothesized structure of factors, with Chi-Square statistic equal to 8293.0, RMSEA (root mean square error of approximation equal to 0.055, RMR (root mean square residual equal to 0.031, TLI (Tucker-Lewis index, CFI (comparative fit index, IFI (incremental fit index and GFI (goodness of fit index 0.919, 0.926, 0.920, 0.915, respectively. Conclusion  The reliability and validity of the servicemen occupational stress scale meet the standards for scale designing.

  4. Reactivity to interpersonal stress in patients with eating disorders: A systematic review and meta-analysis of studies using an experimental paradigm.

    Science.gov (United States)

    Monteleone, Alessio Maria; Treasure, Janet; Kan, Carol; Cardi, Valentina

    2018-04-01

    Reactivity to interpersonal stress in patients with eating disorders: A systematic review and meta-analysis of studies using an experimental paradigm. NEUROSCI BIOBEHAV REV XXX-XXX, 2018.- Social difficulties have been implicated in the development and maintenance of eating disorder symptoms. The aim of this work was to conduct a systematic review and meta-analysis of experimental studies testing patientsö reactivity to interpersonal stress, compared to healthy controls. Thirty-four studies were included. Meta-analyses were conducted on 16 studies and on following outcomes: attention bias and interference to threatening faces, cortisol, heart rate and negative affect before and after exposure to interpersonal stress. Patients showed heightened attention bias and interference to threatening faces. Lower heart rate after exposure to interpersonal stress and greater negative affect before and after interpersonal stress were observed in the clinical group compared to controls. Surprisingly, only a small minority of studies included measures of abnormal eating behaviour and attitudes. This seems a missed opportunity for testing the causal and maintaining role that abnormalities in interpersonal stress response play in eating disorders. Nonetheless, findings corroborate the hypothesis that patients' response to interpersonal stress differs from that of healthy controls. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Stress Sensitivity Is Associated with Differential Accumulation of Reactive Oxygen and Nitrogen Species in Maize Genotypes with Contrasting Levels of Drought Tolerance

    Science.gov (United States)

    Yang, Liming; Fountain, Jake C.; Wang, Hui; Ni, Xinzhi; Ji, Pingsheng; Lee, Robert D.; Kemerait, Robert C.; Scully, Brian T.; Guo, Baozhu

    2015-01-01

    Drought stress decreases crop growth, yield, and can further exacerbate pre-harvest aflatoxin contamination. Tolerance and adaptation to drought stress is an important trait of agricultural crops like maize. However, maize genotypes with contrasting drought tolerances have been shown to possess both common and genotype-specific adaptations to cope with drought stress. In this research, the physiological and metabolic response patterns in the leaves of maize seedlings subjected to drought stress were investigated using six maize genotypes including: A638, B73, Grace-E5, Lo964, Lo1016, and Va35. During drought treatments, drought-sensitive maize seedlings displayed more severe symptoms such as chlorosis and wilting, exhibited significant decreases in photosynthetic parameters, and accumulated significantly more reactive oxygen species (ROS) and reactive nitrogen species (RNS) than tolerant genotypes. Sensitive genotypes also showed rapid increases in enzyme activities involved in ROS and RNS metabolism. However, the measured antioxidant enzyme activities were higher in the tolerant genotypes than in the sensitive genotypes in which increased rapidly following drought stress. The results suggest that drought stress causes differential responses to oxidative and nitrosative stress in maize genotypes with tolerant genotypes with slower reaction and less ROS and RNS production than sensitive ones. These differential patterns may be utilized as potential biological markers for use in marker assisted breeding. PMID:26492235

  6. Stress Sensitivity Is Associated with Differential Accumulation of Reactive Oxygen and Nitrogen Species in Maize Genotypes with Contrasting Levels of Drought Tolerance

    Directory of Open Access Journals (Sweden)

    Liming Yang

    2015-10-01

    Full Text Available Drought stress decreases crop growth, yield, and can further exacerbate pre-harvest aflatoxin contamination. Tolerance and adaptation to drought stress is an important trait of agricultural crops like maize. However, maize genotypes with contrasting drought tolerances have been shown to possess both common and genotype-specific adaptations to cope with drought stress. In this research, the physiological and metabolic response patterns in the leaves of maize seedlings subjected to drought stress were investigated using six maize genotypes including: A638, B73, Grace-E5, Lo964, Lo1016, and Va35. During drought treatments, drought-sensitive maize seedlings displayed more severe symptoms such as chlorosis and wilting, exhibited significant decreases in photosynthetic parameters, and accumulated significantly more reactive oxygen species (ROS and reactive nitrogen species (RNS than tolerant genotypes. Sensitive genotypes also showed rapid increases in enzyme activities involved in ROS and RNS metabolism. However, the measured antioxidant enzyme activities were higher in the tolerant genotypes than in the sensitive genotypes in which increased rapidly following drought stress. The results suggest that drought stress causes differential responses to oxidative and nitrosative stress in maize genotypes with tolerant genotypes with slower reaction and less ROS and RNS production than sensitive ones. These differential patterns may be utilized as potential biological markers for use in marker assisted breeding.

  7. Laboratory scale characterizations of the mixing zone for reactive transport in a carbonate system

    International Nuclear Information System (INIS)

    Kassab, M.F.

    2012-01-01

    We have performed laboratory-scale percolation experiments combining hydrodynamic and geochemical reaction processes in a unique setup to study the evolution of permeability induced by dissolution reactions in a natural Carbonate system. First, the key parameters controlling Calcite dissolution due to mixing of two end member solutions representing fresh and sea waters are assessed through typical geochemical modeling. Both solutions are at equilibrium with Calcite and are associated with different values of partial pressure of CO 2 and salinity. Mixing of the two selected end members provides a sub saturated solution with low and moderate ionic strength, high pCO 2 , and high salinity. Modeling results reveal that the maximum sub saturation is expected to occur for mixing ratios of about 15%. The expected dissolved Calcite until equilibrium attains its maximum at a mixing ratio of about 45%. Experimental results indicate that the calcite dissolution rate at a 15% mixing ratio is higher than that observed at 45% mixing ratio. The outlet solution from the sample reactor is always under saturated with respect to Calcite. Permeability of the tested sample displays a rapid decrease during the beginning of injection. It then shows a stable behavior until the end of percolation when the porosity of the sample increases due to dissolution. To understand permeability and porosity evolution obtained from the mixing experiments we perform dissolution experiments under different dissolution regimes by injection of deionized water (DW) and/or DW enriched with CO 2 . It is observed that permeability decreases when DW is injected whereas it increases following injection of DW enriched with CO 2 . The observed global dissolution rate of Calcite is larger for the experiments with DW enriched with CO 2 than for those performed with DW. The observed permeability reduction is due to the clogging of connected pore caused by migration of micro particles detaching from the host porous

  8. Adaptation to Portuguese of the Depression, Anxiety and Stress Scales (DASS).

    Science.gov (United States)

    Apóstolo, João Luís Alves; Mendes, Aida Cruz; Azeredo, Zaida Aguiar

    2006-01-01

    To adapt to Portuguese, of Portugal, the Depression, Anxiety and Stress Scales, a 21-item short scale (DASS 21), designed to measure depression, anxiety and stress. After translation and back-translation with the help of experts, the DASS 21 was administered to patients in external psychiatry consults (N=101), and its internal consistency, construct validity and concurrent validity were measured. The DASS 21 properties certify its quality to measure emotional states. The instrument reveals good internal consistency. Factorial analysis shows that the two-factor structure is more adequate. The first factor groups most of the items that theoretically assess anxiety and stress, and the second groups most of the items that assess depression, explaining, on the whole, 58.54% of total variance. The strong positive correlation between the DASS 21 and the Hospital Anxiety and Depression scale (HAD) confirms the hypothesis regarding the criterion validity, however, revealing fragilities as to the divergence between theoretically different constructs.

  9. Development of the perceived stress scale for people living with HIV/AIDS in China.

    Science.gov (United States)

    Su, Xiaoyou; Lau, Joseph T F; Mak, Winnie W S; Chen, Lin; Feng, Tiejian; Chen, Xi; Liu, Chuliang; Liu, Jun; Liu, De; Cheng, Jinquan

    2008-12-01

    Stress among people living with HIV/AIDS (PLWHA) is associated with psychological morbidity. There are only a few stress scales specially developed for PLWHA and none of them is in Chinese. This study develops and validates a new Chinese Perceived Stress Scale among PLWHA (PSSHIV) in Shenzhen of Guangdong Province and Hengyang of Hunan Province in China during September 2006 through July 2007. In-depth interviews were administered to 58 PLWHA (33 males, mean age, 32) to generate the items, while 215 other PLWHA were interviewed in another survey to validate the instrument (136 males, mean age, 33). Exploratory factor analysis yielded 8 factors (percent variance explained, 71.47%), namely: social/psychological problems, sexual relationship, functional problems, social acceptance/rejection issues, work-related issues, family/offspring issues, accessibility to treatment, and treatment outcomes. The Cronbach alpha values ranged from 0.76 to 0.94 for the overall scale and the 8 subscales. The scores of the overall scale, the social/psychological problems, and functional problems subscales of the PSSHIV were significantly correlated with the Perceived Stress Scale (PSS), Depression, Anxiety and Stress Scale (DASS), and all domains of the Medical Outcomes Study HIV Health Survey (MOS-HIV) (correlation coefficient = 0.50 to 0.71 for positive correlations, and -0.73 to -0.21 for negative correlations, p DASS, and MOS-HIV (correlation coefficient = 0.16 to 0.39 for positive correlation, -0.58 to -0.15 for negative correlation, p < 0.05). This new instrument collected information from the PLWHA from qualitative interviews and the items are specific to the HIV/AIDS context. PSSHIV can be used for assessing the level of stress faced by PLWHA in China.

  10. The psychometric properties of the Perceived Stress Scale-10 among patients with systemic lupus erythematosus.

    Science.gov (United States)

    Mills, S D; Azizoddin, D; Racaza, G Z; Wallace, D J; Weisman, M H; Nicassio, P M

    2017-10-01

    Objective Systemic lupus erythematosus (SLE) is a chronic, multisystem autoimmune disease characterized by periods of remission and recurrent flares, which have been associated with stress. Despite the significance of stress in this disease, the Perceived Stress Scale-10 has yet to be psychometrically evaluated in patients with SLE. Methods Exploratory factor analysis was used to examine the structural validity of the Perceived Stress Scale-10 among patients with SLE ( N = 138) receiving medical care at Cedars Sinai Medical Center. Cronbach's coefficient alpha was used to examine internal consistency reliability, and Pearson product-moment correlations were used to examine convergent validity with measures of anxiety, depression, helplessness, and disease activity. Results Exploratory factor analysis provided support for a two-factor structure (comparative fit index = .95; standardized root mean residual = .04; root mean square error of approximation = .08). Internal consistency reliability was good for both factors (α = .84 and .86). Convergent validity was evidenced via significant correlations with measures of anxiety, depression, and helplessness. There were no significant correlations with the measure of disease activity. Conclusion The Perceived Stress Scale-10 can be used to examine perceived stress among patients with SLE.

  11. Final Report, University of California Merced: Uranium and strontium fate in waste-weathered sediments: Scaling of molecular processes to predict reactive transport (DE-SC0007095)

    Energy Technology Data Exchange (ETDEWEB)

    O' Day, Peggy Anne [University of California Merced; Chorover, Jon [University of Arizona; Steefel, Carl [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mueller, Karl [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Um, Wooyong [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-06-30

    Objectives of the Project: 1. Determine the process coupling that occurs between mineral transformation and contaminant (U and Sr) speciation in acid-uranium waste weathered Hanford sediments. 2. Establish linkages between molecular-scale contaminant speciation and meso-scale contaminant lability, release and reactive transport. 3. Make conjunctive use of molecular- to bench-scale data to constrain the development of a mechanistic, reactive transport model that includes coupling of contaminant sorption-desorption and mineral transformation reactions. Hypotheses Tested: Uranium and strontium speciation in legacy sediments from the U-8 and U-12 Crib sites can be reproduced in bench-scale weathering experiments conducted on unimpacted Hanford sediments from the same formations; Reactive transport modeling of future uranium and strontium releases from the vadose zone of acid-waste weathered sediments can be effectively constrained by combining molecular-scale information on contaminant bonding environment with grain-scale information on contaminant phase partitioning, and meso-scale kinetic data on contaminant release from the waste-weathered porous media; Although field contamination and laboratory experiments differ in their diagenetic time scales (decades for field vs. months to years for lab), sediment dissolution, neophase nucleation, and crystal growth reactions that occur during the initial disequilibrium induced by waste-sediment interaction leave a strong imprint that persists over subsequent longer-term equilibration time scales and, therefore, give rise to long-term memory effects. Enabling Capabilities Developed: Our team developed an iterative measure-model approach that is broadly applicable to elucidate the mechanistic underpinnings of reactive contaminant transport in geomedia subject to active weathering.

  12. Homogeneity of small-scale earthquake faulting, stress, and fault strength

    Science.gov (United States)

    Hardebeck, J.L.

    2006-01-01

    Small-scale faulting at seismogenic depths in the crust appears to be more homogeneous than previously thought. I study three new high-quality focal-mechanism datasets of small (M angular difference between their focal mechanisms. Closely spaced earthquakes (interhypocentral distance scales, the crustal stress orientation and fault strength (coefficient of friction) are inferred to be homogeneous as well, to produce such similar earthquakes. Over larger length scales (???2-50 km), focal mechanisms become more diverse with increasing interhypocentral distance (differing on average by 40-70??). Mechanism variability on ???2- to 50 km length scales can be explained by ralatively small variations (???30%) in stress or fault strength. It is possible that most of this small apparent heterogeneity in stress of strength comes from measurement error in the focal mechanisms, as negligibble variation in stress or fault strength (<10%) is needed if each earthquake is assigned the optimally oriented focal mechanism within the 1-sigma confidence region. This local homogeneity in stress orientation and fault strength is encouraging, implying it may be possible to measure these parameters with enough precision to be useful in studying and modeling large earthquakes.

  13. Stress and adhesion of chromia-rich scales on ferritic stainless steels in relation with spallation

    Directory of Open Access Journals (Sweden)

    A. Galerie

    2004-03-01

    Full Text Available The relation between chromia scale spallation during oxidation or cooling down of ferritic stainless steels is generally discussed in terms of mechanical stresses induced by volume changes or differential thermal expansion. In the present paper, growth and thermal stress measurements in scales grown on different ferritic steel grades have shown that the main stress accumulation occurs during isothermal scale growth and that thermal stresses are of minor importance. However, when spallation occurs, it is always during cooling down. Steel-oxide interface undulation seems to play a major role at this stage, thus relating spallation to the metal mechanical properties, thickness and surface preparation. A major influence on spallation of the minor stabilizing elements of the steels was observed which could not be related to any difference in stress state. Therefore, an original inverted blister test was developed to derive quantitative values of the metal-oxide adhesion energy. These values clearly confirmed that this parameter was influenced by scale thickness and by minor additions, titanium greatly increasing adhesion whereas niobium decreased it.

  14. Sex differences in platelet reactivity and cardiovascular and psychological response to mental stress in patients with stable ischemic heart disease: insights from the REMIT study.

    Science.gov (United States)

    Samad, Zainab; Boyle, Stephen; Ersboll, Mads; Vora, Amit N; Zhang, Ye; Becker, Richard C; Williams, Redford; Kuhn, Cynthia; Ortel, Thomas L; Rogers, Joseph G; O'Connor, Christopher M; Velazquez, Eric J; Jiang, Wei

    2014-10-21

    Although emotional stress is associated with ischemic heart disease (IHD) and related clinical events, sex-specific differences in the psychobiological response to mental stress have not been clearly identified. We aimed to study the differential psychological and cardiovascular responses to mental stress between male and female patients with stable IHD. Patients with stable IHD enrolled in the REMIT (Responses of Mental Stress-Induced Myocardial Ischemia to Escitalopram) study underwent psychometric assessments, transthoracic echocardiography, and platelet aggregation studies at baseline and after 3 mental stress tasks. Mental stress-induced myocardial ischemia (MSIMI) was defined as the development or worsening of regional wall motion abnormality, reduction of left ventricular ejection fraction (LVEF) ≥8% by transthoracic echocardiography, and/or ischemic ST-segment change on electrocardiogram during 1 or more of the 3 mental stress tasks. In the 310 participants with known IHD (18% women, 82% men), most baseline characteristics were similar between women and men (including heart rate, blood pressure, and LVEF), although women were more likely to be nonwhite, living alone (p mental stress, women had more MSIMI (57% vs. 41%; p mental stress in women and men. Further studies should test the association of sex differences in cardiovascular and platelet reactivity in response to mental stress and long-term outcomes. (Responses of Myocardial Ischemia to Escitalopram Treatment [REMIT]; NCT00574847). Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  15. Dynamic Pore-Scale Imaging of Reactive Transport in Heterogeneous Carbonates at Reservoir Conditions Across Multiple Dissolution Regimes

    Science.gov (United States)

    Menke, H. P.; Bijeljic, B.; Andrew, M. G.; Blunt, M. J.

    2014-12-01

    of compact dissolution. This study serves as a unique benchmark for pore-scale reactive transport modelling directly on the binarized Micro-CT images. Dynamic pore-scale imaging methods offer advantages in helping explain the dominant processes at the pore scale so that they may be up-scaled for accurate model prediction.

  16. Large-Scale Parallel Finite Element Analysis of the Stress Singular Problems

    International Nuclear Information System (INIS)

    Noriyuki Kushida; Hiroshi Okuda; Genki Yagawa

    2002-01-01

    In this paper, the convergence behavior of large-scale parallel finite element method for the stress singular problems was investigated. The convergence behavior of iterative solvers depends on the efficiency of the pre-conditioners. However, efficiency of pre-conditioners may be influenced by the domain decomposition that is necessary for parallel FEM. In this study the following results were obtained: Conjugate gradient method without preconditioning and the diagonal scaling preconditioned conjugate gradient method were not influenced by the domain decomposition as expected. symmetric successive over relaxation method preconditioned conjugate gradient method converged 6% faster as maximum if the stress singular area was contained in one sub-domain. (authors)

  17. The relationship between the population size and the postirradiation mortality of mice with respect to individual differences in stress reactivity

    International Nuclear Information System (INIS)

    Pospisil, M.; Pipalova, I.; Netikova, J.

    1976-01-01

    Differences in radiosensitivity, expressed by the death rate up to the 30th day after irradiation by single whole-body exposures in the region of LD 50 , were followed in mice caged in groups by five, 15 and 25 individuals. No marked differences in the whole-group mortality of differently sized collectives were detected. Preirradiation as well as postirradiation leucocyte counts (after a sublethal irradiation) exhibit, however, differences, which correspond to an assumed different degree of the adrenocortical activity in differently sized collectives. Also the follow-up of the stress reactivity of the animals by measuring the Na/K ratio in 24-hour-samples of urine prior to irradiation demonstrated marked differences between the groups with low number and high number of animals in a cage. By correlating values of this indirect indicator of the adrenocortical activity with manifestations of the individual radiosensitivity it was found that the extremely hyporeactive animals (belonging to groups with five animals per cage) and the extremely hyperreactive ones (belonging to groups with 25 animals per cage) exhibit a markedly higher mortality. The absence of differences in the whole-group mortality of differently sized collectives can be explained by the existence of nonlinear 'U'-shaped relations between the adrenocortical activity and the individuals' radiosensitivity. The results support the conception on the unfavorable prognostic significance of unbalanced reactions of homeostatic functions of system regulation under conditions of radiation syndrome. (orig.) [de

  18. Sex differences in salivary cortisol reactivity to the Trier Social Stress Test (TSST): A meta-analysis.

    Science.gov (United States)

    Liu, Jenny J W; Ein, Natalie; Peck, Katlyn; Huang, Vivian; Pruessner, Jens C; Vickers, Kristin

    2017-08-01

    Some, but not all studies using the Trier Social Stress Test (TSST) have demonstrated evidence in support of sex differences in salivary cortisol. The aim of the current meta-analysis is to examine sex differences in salivary cortisol following exposure to the TSST. We further explored the effects of modifications to the TSST protocol and procedural variations as potential moderators. We searched articles published from January, 1993 to February, 2016 in MedLine, PsychINFO, and ProQuest Theses and Dissertations. This meta-analysis is based on 34 studies, with a total sample size of 1350 individuals (640 women and 710 men). Using a random effects model, we found significant heterogeneity in salivary cortisol output across sexes, such that men were observed to have higher cortisol values at peak and recovery following the TSST compared to women. Modifications to the sampling trajectory of cortisol (i.e., duration of acclimation, peak sampling time, and duration of recovery) significantly moderated the heterogeneity across both sexes. Further, there are observed sex differences at various time points of the reactive cortisol following the TSST. Lastly, current results suggest that these sex differences can be, at least in part, attributed to variations in methodological considerations across studies. Future research could advance this line of inquiry by using other methods of analyses (e.g., area under the curve; AUC), in order to better understand the effects of methodological variations and their implications for research design. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Characteristics of the Residual Stress tensor when filter width is larger than the Ozmidov scale

    Science.gov (United States)

    de Bragança Alves, Felipe Augusto; de Bruyn Kops, Stephen

    2017-11-01

    In stratified turbulence, the residual stress tensor is statistically anisotropic unless the smallest resolved length scale is smaller than the Ozmidov scale and the buoyancy Reynolds number is sufficiently high for there to exist a range of scales that is statistically isotropic. We present approximations to the residual stress tensor that are derived analytically. These approximations are evaluated by filtering data from direct numerical simulations of homogeneous stratified turbulence, with unity Prandtl number, resolved on up to 8192 × 8192 × 4096 grid points along with an isotropic homogeneous case resolved on 81923 grid points. It is found that the best possible scaling of the strain rate tensor yields a residual stress tensor (RST) that is less well statistically aligned with the exact RST than a randomly generated tensor. It is also found that, while a scaling of the strain rate tensor can dissipate the right amount of energy, it produces incorrect anisotropic dissipation, removing energy from the wrong components of the velocity vector. We find that a combination of the strain rate tensor and a tensor related to energy redistribution caused by a Newtonian fluid viscous stress yields an excellent tensorial basis for modelling the RST.

  20. Multimodal assessment of emotional reactivity in borderline personality pathology: the moderating role of posttraumatic stress disorder symptoms.

    Science.gov (United States)

    Dixon-Gordon, Katherine L; Gratz, Kim L; Tull, Matthew T

    2013-08-01

    Emotional reactivity has been theorized to play a central role in borderline personality (BP) pathology. Although growing research provides evidence for subjective emotional reactivity in BP pathology, research on physiological or biological reactivity among people with BP pathology is less conclusive. With regard to biological reactivity in particular, research on cortisol reactivity (a neurobiological marker of emotional reactivity) in response to stressors among individuals with BP pathology has produced contradictory results and highlighted the potential moderating role of PTSD-related pathology. Thus, this study sought to examine the moderating role of PTSD symptoms in the relation between BP pathology and both subjective (self-report) and biological (cortisol) emotional reactivity to a laboratory stressor. Participants were 171 patients in a residential substance use disorder treatment center. Consistent with hypotheses, results revealed a significant main effect of BP pathology on subjective emotional reactivity to the laboratory stressor. Furthermore, results revealed a significant interaction between BP pathology and PTSD symptoms in the prediction of cortisol reactivity, such that BP pathology was associated with heightened cortisol reactivity only among participants with low levels of PTSD symptoms. Similar findings were obtained when examining the interaction between BP pathology and the reexperiencing and avoidance/numbing symptoms of PTSD specifically. Results highlight the moderating role of PTSD symptoms in the BP-reactivity relation. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. Altered cardiovascular reactivity and osmoregulation during hyperosmotic stress in adult rats developmentally exposed to polybrominated diphenyl ethers (PBDEs)

    International Nuclear Information System (INIS)

    Shah, Ashini; Coburn, Cary G.; Watson-Siriboe, Abena; Whitley, Rebecca; Shahidzadeh, Anoush; Gillard, Elizabeth R.; Nichol, Robert; Leon-Olea, Martha; Gaertner, Mark; Kodavanti, Prasada Rao S.; Curras-Collazo, Margarita C.

    2011-01-01

    Polybrominated diphenyl ethers (PBDEs) and the structurally similar chemicals polychlorinated biphenyls (PCBs) disrupt the function of multiple endocrine systems. PCBs and PBDEs disrupt the secretion of vasopressin (VP) from the hypothalamus during osmotic activation. Since the peripheral and central vasopressinergic axes are critical for osmotic and cardiovascular regulation, we examined whether perinatal PBDE exposure could impact these functions during physiological activation. Rats were perinatally dosed with a commercial PBDE mixture, DE-71. Dams were given 0 (corn oil control), 1.7 (low dose) or 30.6 mg/kg/day (high dose) in corn oil from gestational day (GD) 6 through postnatal day (PND) 21 by oral gavage. In the male offspring exposed to high dose PBDE plasma thyroxine and triiodothyronine levels were reduced at PND 21 and recovered to control levels by PND 60 when thyroid stimulating hormone levels were elevated. At 14-18 months of age, cardiovascular responses were measured in four groups of rats: Normal (Oil, normosmotic condition), Hyper (Oil, hyperosmotic stress), Hyper PBDE low (1.7 mg/kg/day DE-71 perinatally, hyperosmotic stress), and Hyper PBDE high (30.6 mg/kg/day DE-71 perinatally, hyperosmotic stress). Systolic blood pressure (BP), diastolic BP, and heart rate (HR) were determined using tail cuff sphygmomanometry and normalized to pretreatment values (baseline) measured under basal conditions. Hyperosmotic treatment yielded significant changes in systolic BP in PBDE exposed rats only. Hyper PBDE low and high dose rats showed 36.1 and 64.7% greater systolic BP responses at 3 h post hyperosmotic injection relative to pretreatment baseline, respectively. No treatment effects were measured for diastolic BP and HR. Hyper and Hyper PBDE rats showed increased mean plasma osmolality values by 45 min after injection relative to normosmotic controls. In contrast to Hyper rats, Hyper PBDE (high) rats showed a further increase in mean plasma osmolality at 3

  2. Lack of independent relationships between left ventricular mass and cardiovascular reactivity to physical and psychological stress in the Coronary Artery Risk Development in Young Adults (CARDIA) Study.

    Science.gov (United States)

    Markovitz, J H; Raczynski, J M; Lewis, C E; Flack, J; Chesney, M; Chettur, V; Hardin, J M; Johnson, E

    1996-09-01

    The objective of this study was to determine whether exaggerated blood pressure (BP) reactivity to stress and psychosocial characteristics are related to left ventricular mass (LVM) in a large cohort of young adults. Analyses were conducted with 3,742 participants of the CARDIA study (945 white men, 1,024 white women, 781 black men, and 992 black women), evaluated in 1990 to 1091 with echocardiographic measurement of LVM. Analyses were stratified by gender and race. The relationships of LVM/height2.7 and cardiovascular reactivity to physical and psychological stressors (treadmill exercise, cold pressor, video game, and star-tracing tasks), were examined in both univariate and multivariate analyses adjusting for baseline BP, weight, and other relevant biobehavioral variables. The relationships between LVM and several psychosocial characteristics (hostility, anger suppression, anxiety, depressive symptoms, and education) were also assessed. Systolic blood pressure (SBP) reactivity to exercise was significantly related to LVM in black and white men; LVM was 10% greater among white men with exaggerated (upper quintile) peak exercise SBP than among other white men. SBP reactivity to the cold pressor test was related to LVM in all race/gender groups, although the relationship remained significant only among white men and women in the multivariate analysis. Diastolic blood pressure (DBP) reactivity to the video game was related to LVM only among black men in adjusted analyses. After adjusting for resting BP, weight, and other covariates in linear multiple regression models, SBP reactivity to exercise explained only 3% of the variance in LVM among white men. Otherwise, reactivity to other stressors or psychosocial variables accounted for no more than 1% of the variance in LVM. It was concluded that among a cohort of young adults, blood pressure reactivity to physical and mental stressors did not add substantially to the prediction of LVM when resting BP, weight, and other

  3. Wafer-Scale Hierarchical Nanopillar Arrays Based on Au Masks and Reactive Ion Etching for Effective 3D SERS Substrate

    Directory of Open Access Journals (Sweden)

    Dandan Men

    2018-02-01

    Full Text Available Two-dimensional (2D periodic micro/nanostructured arrays as SERS substrates have attracted intense attention due to their excellent uniformity and good stability. In this work, periodic hierarchical SiO2 nanopillar arrays decorated with Ag nanoparticles (NPs with clean surface were prepared on a wafer-scale using monolayer Au NP arrays as masks, followed by reactive ion etching (RIE, depositing Ag layer and annealing. For the prepared SiO2 nanopillar arrays decorated with Ag NPs, the size of Ag NPs was tuned from ca. 24 to 126 nanometers by controlling the deposition thickness of Ag film. Importantly, the SiO2 nanopillar arrays decorated with Ag NPs could be used as highly sensitive SERS substrate for the detection of 4-aminothiophenol (4-ATP and rhodamine 6G (R6G due to the high loading of Ag NPs and a very uniform morphology. With a deposition thickness of Ag layer of 30 nm, the SiO2 nanopillar arrays decorated with Ag NPs exhibited the best sensitive SERS activity. The excellent SERS performance of this substrate is mainly attributed to high-density “hotspots” derived from nanogaps between Ag NPs. Furthermore, this strategy might be extended to synthesize other nanostructured arrays with a large area, which are difficult to be prepared only via conventional wet-chemical or physical methods.

  4. Wafer-Scale Hierarchical Nanopillar Arrays Based on Au Masks and Reactive Ion Etching for Effective 3D SERS Substrate.

    Science.gov (United States)

    Men, Dandan; Wu, Yingyi; Wang, Chu; Xiang, Junhuai; Yang, Ganlan; Wan, Changjun; Zhang, Honghua

    2018-02-04

    Two-dimensional (2D) periodic micro/nanostructured arrays as SERS substrates have attracted intense attention due to their excellent uniformity and good stability. In this work, periodic hierarchical SiO₂ nanopillar arrays decorated with Ag nanoparticles (NPs) with clean surface were prepared on a wafer-scale using monolayer Au NP arrays as masks, followed by reactive ion etching (RIE), depositing Ag layer and annealing. For the prepared SiO₂ nanopillar arrays decorated with Ag NPs, the size of Ag NPs was tuned from ca. 24 to 126 nanometers by controlling the deposition thickness of Ag film. Importantly, the SiO₂ nanopillar arrays decorated with Ag NPs could be used as highly sensitive SERS substrate for the detection of 4-aminothiophenol (4-ATP) and rhodamine 6G (R6G) due to the high loading of Ag NPs and a very uniform morphology. With a deposition thickness of Ag layer of 30 nm, the SiO₂ nanopillar arrays decorated with Ag NPs exhibited the best sensitive SERS activity. The excellent SERS performance of this substrate is mainly attributed to high-density "hotspots" derived from nanogaps between Ag NPs. Furthermore, this strategy might be extended to synthesize other nanostructured arrays with a large area, which are difficult to be prepared only via conventional wet-chemical or physical methods.

  5. Groundwater development stress: Global-scale indices compared to regional modeling

    Science.gov (United States)

    Alley, William; Clark, Brian R.; Ely, Matt; Faunt, Claudia

    2018-01-01

    The increased availability of global datasets and technologies such as global hydrologic models and the Gravity Recovery and Climate Experiment (GRACE) satellites have resulted in a growing number of global-scale assessments of water availability using simple indices of water stress. Developed initially for surface water, such indices are increasingly used to evaluate global groundwater resources. We compare indices of groundwater development stress for three major agricultural areas of the United States to information available from regional water budgets developed from detailed groundwater modeling. These comparisons illustrate the potential value of regional-scale analyses to supplement global hydrological models and GRACE analyses of groundwater depletion. Regional-scale analyses allow assessments of water stress that better account for scale effects, the dynamics of groundwater flow systems, the complexities of irrigated agricultural systems, and the laws, regulations, engineering, and socioeconomic factors that govern groundwater use. Strategic use of regional-scale models with global-scale analyses would greatly enhance knowledge of the global groundwater depletion problem.

  6. Validation of the Minority Stress Scale Among Italian Gay and Bisexual Men.

    Science.gov (United States)

    Pala, Andrea Norcini; Dell'Amore, Francesca; Steca, Patrizia; Clinton, Lauren; Sandfort, Theodorus; Rael, Christine

    2017-12-01

    The experience of sexual orientation stigma (e.g., homophobic discrimination and physical aggression) generates minority stress, a chronic form of psychosocial stress. Minority stress has been shown to have a negative effect on gay and bisexual men's (GBM's) mental and physical health, increasing the rates of depression, suicidal ideation, and HIV risk behaviors. In conservative religious settings, such as Italy, sexual orientation stigma can be more frequently and/or more intensively experienced. However, minority stress among Italian GBM remains understudied. The aim of this study was to explore the dimensionality, internal reliability, and convergent validity of the Minority Stress Scale (MSS), a comprehensive instrument designed to assess the manifestations of sexual orientation stigma. The MSS consists of 50 items assessing (a) Structural Stigma, (b) Enacted Stigma, (c) Expectations of Discrimination, (d) Sexual Orientation Concealment, (e) Internalized Homophobia Toward Others, (f) Internalized Homophobia toward Oneself, and (g) Stigma Awareness. We recruited an online sample of 451 Italian GBM to take the MSS. We tested convergent validity using the Perceived Stress Questionnaire. Through exploratory factor analysis, we extracted the 7 theoretical factors and an additional 3-item factor assessing Expectations of Discrimination From Family Members. The MSS factors showed good internal reliability (ordinal α > .81) and good convergent validity. Our scale can be suitable for applications in research settings, psychosocial interventions, and, potentially, in clinical practice. Future studies will be conducted to further investigate the properties of the MSS, exploring the association with additional health-related measures (e.g., depressive symptoms and anxiety).

  7. Construction and evaluation of a self rating scale for stress-induced exhaustion disorder, the Karolinska Exhaustion Disorder Scale.

    Science.gov (United States)

    Besèr, Aniella; Sorjonen, Kimmo; Wahlberg, Kristina; Peterson, Ulla; Nygren, Ake; Asberg, Marie

    2014-02-01

    Prolonged stress (≥ six months) may cause a condition which has been named exhaustion disorder (ED) with ICD-10 code F43.8. ED is characterised by exhaustion, cognitive problems, poor sleep and reduced tolerance to further stress. ED can cause long term disability and depressive symptoms may develop. The aim was to construct and evaluate a self-rating scale, the Karolinska Exhaustion Disorder Scale (KEDS), for the assessment of ED symptoms. A second aim was to examine the relationship between self-rated symptoms of ED, depression, and anxiety using KEDS and the Hospital Anxiety and Depression Scale (HAD). Items were selected based on their correspondence to criteria for ED as formulated by the Swedish National Board of Health and Welfare (NBHW), with seven response alternatives in a Likert-format. Self-ratings performed by 317 clinically assessed participants were used to analyse the scale's psychometric properties. KEDS consists of nine items with a scale range of 0-54. Receiver operating characteristics analysis demonstrated that a cut-off score of 19 was accompanied by high sensitivity and specificity (each above 95%) in the discrimination between healthy subjects and patients with ED. Reliability was satisfactory and confirmatory factor analysis revealed that ED, depression and anxiety are best regarded as different phenomena. KEDS may be a useful tool in the assessment of symptoms of Exhaustion Disorder in clinical as well as research settings. There is evidence that the symptom clusters of ED, anxiety and depression, respectively, reflect three different underlying dimensions. © 2013 The Authors. Scandinavian Journal of Psychology published by Scandinavian Psychological Associations and John Wiley & Sons Ltd.

  8. Depression, Anxiety and Stress Scale (DASS): The Study of Validity and Reliability

    Science.gov (United States)

    Basha, Ertan; Kaya, Mehmet

    2016-01-01

    The purpose of this study is to examine validity and reliability of the Albanian version of the Depression, Anxiety and Stress Scale (DASS), which is developed by Lovibond and Lovibond (1995). The sample of this study is consisted of 555 subjects who were living in Kosovo. The results of confirmatory factor analysis indicated 42 items loaded on…

  9. Psychometric Properties of the Depression Anxiety and Stress Scale-21 in Older Primary Care Patients

    OpenAIRE

    Gloster, Andrew T.; Rhoades, Howard M.; Novy, Diane; Klotsche, Jens; Senior, Ashley; Kunik, Mark; Wilson, Nancy; Stanley, Melinda A.

    2008-01-01

    The Depression Anxiety Stress Scale (DASS) was designed to efficiently measure the core symptoms of anxiety and depression and has demonstrated positive psychometric properties in adult samples of anxiety and depression patients and student samples. Despite these findings, the psychometric properties of the DASS remain untested in older adults, for whom the identification of efficient measures of these constructs is especially important.

  10. Suitability of the Depression, Anxiety, and Stress Scale in Parkinson's Disease.

    Science.gov (United States)

    Johnson, Andrew R; Lawrence, Blake J; Corti, Emily J; Booth, Leon; Gasson, N; Thomas, Meghan G; Loftus, A M; Bucks, Romola S

    2016-05-27

    The Depression, Anxiety, and Stress Scale -21 (DASS-21) is a frequently used measure of emotional disturbance symptoms in Parkinson's disease (PD). However, the factor structure of the DASS-21 in PD has yet to be explored. To assess whether the scale is measuring these symptoms in PD in the same way as the general population. The present study fit a series of established DASS-21 factor structures with both confirmatory factor analysis (CFA) and exploratory structural equation modelling (ESEM) using data from 251 participants with PD. The 3-factor ESEM provided the best fit. The depression and stress scales fit well, however, few items on the anxiety subscale loaded clearly, with several items significantly loading onto the depression or stress factors. Whilst the depression and stress subscales appear suitable in PD, poor loadings and internal consistency indicate the anxiety subscale may not accurately assess anxiety symptomology in PD. This may be due to the scale's reliance on physiological symptoms as indicators of anxiety, when many of these are present in PD. Thus, the anxiety subscale of the DASS-21 may not be a suitable measure of anxiety in PD.

  11. Using the Depression, Anxiety, Stress Scales-21 with U.S. Adolescents: An Alternate Models Analysis

    Science.gov (United States)

    Moore, Stephanie A.; Dowdy, Erin; Furlong, Michael J.

    2017-01-01

    As part of universal screening efforts in schools, validated measures that identify internalizing distress are needed. One promising available measure, the Depression, Anxiety, and Stress Scales-21 (DASS-21), has yet to be thoroughly investigated with adolescents in the United States. This study investigated the underlying factor structure of the…

  12. The MMPI-2 Restructured Clinical Scales in the Assessment of Posttraumatic Stress Disorder and Comorbid Disorders

    Science.gov (United States)

    Wolf, Erika J.; Miller, Mark W.; Orazem, Robert J.; Weierich, Mariann R.; Castillo, Diane T.; Milford, Jaime; Kaloupek, Danny G.; Keane, Terence M.

    2008-01-01

    This study examined the psychometric properties of the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) Restructured Clinical Scales (RCSs) in individuals with posttraumatic stress disorder (PTSD) receiving clinical services at Department of Veterans Affairs medical centers. Study 1 included 1,098 men who completed the MMPI-2 and were…

  13. EARLY PROGNOSTIC SCREENING FOR POSTTRAUMATIC STRESS DISORDER WITH THE DAVIDSON TRAUMA SCALE AND THE SPAN

    NARCIS (Netherlands)

    Sijbrandij, Marit; Olff, Miranda; Opmeer, Brent C.; Carlier, Ingrid V. E.; Gersons, Berthold P. R.

    2008-01-01

    Background: This study examined the accuracy of the 17-item. Dutch version of the Davidson Trauma Scale (DTS) and the four-item SPAN (Startle, Physiological Arousal, Anger and Numbness) to detect survivors at risk for posttraumatic stress disorder (PTSD) within the first 2 weeks after the trauma.

  14. Psychometric Properties of an Arabic Version of the Depression Anxiety Stress Scales (DASS)

    Science.gov (United States)

    Moussa, Miriam Taouk; Lovibond, Peter; Laube, Roy; Megahead, Hamido A.

    2017-01-01

    Objective: To translate and evaluate the psychometric properties of an Arabic-language version of the Depression Anxiety Stress Scales (DASS). Method: The items were translated, back translated, refined, and tested in an Australian immigrant sample (N = 220). Results: Confirmatory factor analysis showed that the Arabic DASS discriminates between…

  15. Chinese version of the Perceived Stress Scale-10: A psychometric study in Chinese university students.

    Science.gov (United States)

    Lu, Wei; Bian, Qian; Wang, Wenzheng; Wu, Xiaoling; Wang, Zhen; Zhao, Min

    2017-01-01

    Chinese university students often suffer from acute stress, which can affect their mental health. We measured and evaluated perceived stress in this population using the Simplified Chinese version of the 10-item Perceived Stress Scale (SCPSS-10). The SCPSS-10, Patient Health Questionnaire (PHQ), and Generalized Anxiety Disorder 7-item scale (GAD-7) were conducted in 1096 university students. Two weeks later, 129 participants were re-tested using the SCPSS-10. Exploratory factor analysis yielded two factors with Eigen values of 4.76 and 1.48, accounting for 62.41% of the variance. Confirmatory factor analysis demonstrated good fit of this two-factor model. The internal consistency reliability, as measured by Cronbach's α, was 0.85. The test-retest reliability coefficient was 0.7. The SCPSS-10 exhibited high correlation with the PHQ-9 and GAD-7, indicating an acceptable concurrent validity. The SCPSS-10 exhibited satisfactory psychometric properties in Chinese university students.

  16. Permeable reactive barriers for the remediation of groundwater in a mining area: results for a pilot-scale project

    Science.gov (United States)

    Martinez-Sanchez, Maria Jose; Perez-Sirvent, Carmen; Garcia-Lorenzo, Maria Luz; Martinez-Lopez, Salvadora; Perez-Espinosa, Victor; Gonzalez-Ciudad, Eva; Belen Martinez-Martinez, Lucia; Hernandez, Carmen; Molina-Ruiz, Jose

    2017-04-01

    The Sierra Minera of Cartagena-La Union is located in the Region of Murcia, Southeast of Spain. This zone presents high levels of heavy metals due to natural, geogenic reasons. In addition, the prolonged mining activity, and subsequent abandonment of farms, has had consequences on the environment, including severe affectation of the groundwater in the area. To remediate this situation, the Permeable Reactive Barrier (PRB) technology was assayed, which required in addition to the hydro-geological study of the zone, a careful optimization study for the design and construction of PRBs. For such a purpose a pilot-scale project was developed, and this communication reports some of the most relevant findings obtained after a four-years monitorization period. The selected reactive material for the PRBs was limestone filler. The filler is a waste material produced in many factories in the zone. These residues have good adsorption properties, high alkalinity, low cost and high availability, which make them suitable for use in remediation. The PRB was constituted by a 50% limestone filler and 50% sand, a proportion optimized by means of independent batch experiments. A layer of gravel was placed at the top, and on it a layer of natural soil. The barrier was designed in the form of a continuous trench, because the level of the contaminated groundwater was not very deep. In this way, the barrier could be prepared with standard excavation equipment. Parallel to the barrier, 6 wells where arranged downstream for sample collection. The pH and conductivity of the samples was measured directly in situ, and the content of Zn, Cd, Cu, Fe, and Pb were analyzed in the laboratory. All the samples collected after the PRB was constructed had basic pH values between 7.5 and 8. The conductivity was between 5 and 11 mS / cm except for the well 4, which had a value of 3.70 mS / cm. The concentration values of trace elements were below the detection limit (atomic absorption measurement) in

  17. Geomechanical effects of stress shadow created by large-scale destress blasting

    Directory of Open Access Journals (Sweden)

    Isaac Vennes

    2017-12-01

    Full Text Available This study aims to determine if large-scale choked panel destress blasting can provide sufficient beneficial stress reduction in highly-stressed remnant ore pillar that is planned for production. The orebody is divided into 20 stopes over 2 levels, and 2 panels are choke-blasted in the hanging wall to shield the ore pillar by creating a stress shadow around it. A linear-elastic model of the mining system is constructed with finite difference code FLAC3D. The effect of destress blasting in the panels is simulated by applying a fragmentation factor (α to the rock mass stiffness and a stress reduction factor (β to the current state of stress in the region occupied by the destress panels. As an extreme case, the destress panel is also modeled as a void to obtain the maximum possible beneficial effects of destressing and stress shadow. Four stopes are mined in the stress shadow of the panels in 6 lifts and then backfilled. The effect of destress blasting on the remnant ore pillar is quantified based on stress change and brittle shear ratio (BSR in the stress shadow zone compared to the base case without destress blasting. To establish realistic rock fragmentation and stress reduction factors, model results are compared to measured stress changes reported for case studies at Fraser and Brunswick mines. A 1.5 MPa immediate stress decrease was observed 20 m away from the panel at Fraser Mine, and a 4 MPa immediate stress decrease was observed 25 m away at Brunswick Mine. Comparable results are obtained from the current model with a rock fragmentation factor α of 0.2 and a stress reduction factor β of 0.8. It is shown that a destress blasting with these parameters reduces the major principal stress in the nearest stopes by 10–25 MPa. This yields an immediate reduction of BSR, which is deemed sufficient to reduce volume of ore at risk in the pillar.

  18. COMPI Fertility Problem Stress Scales is a brief, valid and reliable tool for assessing stress in patients seeking treatment

    DEFF Research Database (Denmark)

    Sobral, Maria P.; Costa, Maria E.; Schmidt, Lone

    2017-01-01

    comparability of fertility-related stress across genders and countries. STUDY DESIGN SIZE, DURATION Cross-sectional study. First, we tested the structure of the COMPI-FPSS. Then, reliability and validity (convergent and discriminant) were examined for the final model. Finally, measurement invariance both across...... genders and cultures was tested. PARTICIPANTS/MATERIALS, SETTING, METHODS Our final sample had 3923 fertility patients (1691 men and 2232 women) recruited in clinical settings from seven different countries: Denmark, China, Croatia, Germany, Greece, Hungary and Sweden. Participants had a mean age of 34......STUDY QUESTION Are the Copenhagen Multi‐Centre Psychosocial Infertility research program Fertility Problem Stress Scales (COMPI-FPSS) a reliable and valid measure across gender and culture? SUMMARY ANSWER The COMPI-FPSS is a valid and reliable measure, presenting excellent or good fit...

  19. COMFORT scale: a reliable and valid method to measure the amount of stress of ventilated preterm infants

    NARCIS (Netherlands)

    Wielenga, J. M.; de Vos, R.; de Leeuw, R.; de Haan, R. J.

    2004-01-01

    OBJECTIVE: Assessment of clinimetric properties and diagnostic quality of a stress measurement scale (COMFORT scale). DESIGN: Sample of an open population. SETTING: Neonatology department (Neonatal Intensive Care Unit), Academic Medical Centre/Emma Children's Hospital, Amsterdam, The Netherlands.

  20. Thermal Stress FE Analysis of Large-scale Gas Holder Under Sunshine Temperature Field

    Science.gov (United States)

    Li, Jingyu; Yang, Ranxia; Wang, Hehui

    2018-03-01

    The temperature field and thermal stress of Man type gas holder is simulated by using the theory of sunshine temperature field based on ASHRAE clear-sky model and the finite element method. The distribution of surface temperature and thermal stress of gas holder under the given sunshine condition is obtained. The results show that the thermal stress caused by sunshine can be identified as one of the important factors for the failure of local cracked oil leakage which happens on the sunny side before on the shady side. Therefore, it is of great importance to consider the sunshine thermal load in the stress analysis, design and operation of large-scale steel structures such as the gas holder.

  1. The Arabic Version of The Depression Anxiety Stress Scale-21: Cumulative scaling and discriminant-validation testing.

    Science.gov (United States)

    Ali, Amira Mohammed; Ahmed, Anwar; Sharaf, Amira; Kawakami, Norito; Abdeldayem, Samia M; Green, Joseph

    2017-12-01

    This study aimed to examine the validity of the Arabic version of the Depression Anxiety Stress Scale-21 (DASS-21) in 149 illicit drug users. We calculated α coefficient, inter-item and item-total correlations, coefficients of reproducibility and scalability (CR and CS), item difficulty and discrimination indices. The DASS-21 had an acceptable reliability; but values of the CR and the CS were less than acceptable. Items varied in difficulty and discrimination; some items are candidates for elimination. The DASS-21 is a probabilistic and not a deterministic measure of distress; it has problematic items and needs further investigations. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Increased stress reactivity is associated with cognitive deficits and decreased hippocampal brain-derived neurotrophic factor in a mouse model of affective disorders.

    Science.gov (United States)

    Knapman, A; Heinzmann, J-M; Hellweg, R; Holsboer, F; Landgraf, R; Touma, C

    2010-07-01

    Cognitive deficits are a common feature of major depression (MD), with largely unknown biological underpinnings. In addition to the affective and cognitive symptoms of MD, a dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis is commonly observed in these patients. Increased plasma glucocorticoid levels are known to render the hippocampus susceptible to neuronal damage. This structure is important for learning and memory, creating a potential link between HPA axis dysregulation and cognitive deficits in depression. In order to further elucidate how altered stress responsiveness may contribute to the etiology of MD, three mouse lines with high (HR), intermediate (IR), or low (LR) stress reactivity were generated by selective breeding. The aim of the present study was to investigate whether increased stress reactivity is associated with deficits in hippocampus-dependent memory tests. To this end, we subjected mice from the HR, IR, and LR breeding lines to tests of recognition memory, spatial memory, and depression-like behavior. In addition, measurements of brain-derived neurotrophic factor (BDNF) in the hippocampus and plasma of these animals were conducted. Our results demonstrate that HR mice exhibit hippocampus-dependent memory deficits along with decreased hippocampal, but not plasma, BDNF levels. Thus, the stress reactivity mouse lines are a promising animal model of the cognitive deficits in MD with the unique feature of a genetic predisposition for an altered HPA axis reactivity, which provides the opportunity to explore the progression of the symptoms of MD, predisposing genetic factors as well as new treatment strategies. Copyright 2009 Elsevier Ltd. All rights reserved.

  3. MAPK pathway activation by chronic lead-exposure increases vascular reactivity through oxidative stress/cyclooxygenase-2-dependent pathways

    Energy Technology Data Exchange (ETDEWEB)

    Simões, Maylla Ronacher, E-mail: yllars@hotmail.com [Dept. of Physiological Sciences, Federal University of Espirito Santo, Vitória, ES CEP 29040-091 (Brazil); Department of Pharmacology, Universidad Autonoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid (Spain); Aguado, Andrea [Department of Pharmacology, Universidad Autonoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid (Spain); Fiorim, Jonaína; Silveira, Edna Aparecida; Azevedo, Bruna Fernandes; Toscano, Cindy Medice [Dept. of Physiological Sciences, Federal University of Espirito Santo, Vitória, ES CEP 29040-091 (Brazil); Zhenyukh, Olha; Briones, Ana María [Department of Pharmacology, Universidad Autonoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid (Spain); Alonso, María Jesús [Dept. of Biochemistry, Physiology and Molecular Genetics, Universidad Rey Juan Carlos, Alcorcón (Spain); Vassallo, Dalton Valentim [Dept. of Physiological Sciences, Federal University of Espirito Santo, Vitória, ES CEP 29040-091 (Brazil); Health Science Center of Vitória-EMESCAM, Vitória, ES CEP 29045-402 (Brazil); Salaices, Mercedes, E-mail: mercedes.salaices@uam.es [Department of Pharmacology, Universidad Autonoma de Madrid, Instituto de Investigación Hospital Universitario La Paz (IdiPAZ), Madrid (Spain)

    2015-03-01

    Chronic exposure to low lead concentration produces hypertension; however, the underlying mechanisms remain unclear. We analyzed the role of oxidative stress, cyclooxygenase-2-dependent pathways and MAPK in the vascular alterations induced by chronic lead exposure. Aortas from lead-treated Wistar rats (1st dose: 10 μg/100 g; subsequent doses: 0.125 μg/100 g, intramuscular, 30 days) and cultured aortic vascular smooth muscle cells (VSMCs) from Sprague Dawley rats stimulated with lead (20 μg/dL) were used. Lead blood levels of treated rats attained 21.7 ± 2.38 μg/dL. Lead exposure increased systolic blood pressure and aortic ring contractile response to phenylephrine, reduced acetylcholine-induced relaxation and did not affect sodium nitroprusside relaxation. Endothelium removal and L-NAME left-shifted the response to phenylephrine more in untreated than in lead-treated rats. Apocynin and indomethacin decreased more the response to phenylephrine in treated than in untreated rats. Aortic protein expression of gp91(phox), Cu/Zn-SOD, Mn-SOD and COX-2 increased after lead exposure. In cultured VSMCs lead 1) increased superoxide anion production, NADPH oxidase activity and gene and/or protein levels of NOX-1, NOX-4, Mn-SOD, EC-SOD and COX-2 and 2) activated ERK1/2 and p38 MAPK. Both antioxidants and COX-2 inhibitors normalized superoxide anion production, NADPH oxidase activity and mRNA levels of NOX-1, NOX-4 and COX-2. Blockade of the ERK1/2 and p38 signaling pathways abolished lead-induced NOX-1, NOX-4 and COX-2 expression. Results show that lead activation of the MAPK signaling pathways activates inflammatory proteins such as NADPH oxidase and COX-2, suggesting a reciprocal interplay and contribution to vascular dysfunction as an underlying mechanisms for lead-induced hypertension. - Highlights: • Lead-exposure increases oxidative stress, COX-2 expression and vascular reactivity. • Lead exposure activates MAPK signaling pathway. • ROS and COX-2 activation by

  4. Depression, Anxiety and Stress Scale in patients with tinnitus and hearing loss.

    Science.gov (United States)

    Gomaa, Mohammed Abdel Motaal; Elmagd, Manal Hassan Abo; Elbadry, Mohammed Mohammed; Kader, Rafeek Mohammed Abdel

    2014-08-01

    The study was proposed to evaluate co-morbid depression, anxiety and stress associated with tinnitus patients. The study was done on 196 subjects: 100 patients suffering from subjective tinnitus associated with hearing loss (tinnitus group), 45 patients suffering from hearing loss only (hearing loss group) and 50 healthy subjects not suffering from tinnitus or hearing loss (control group); the age ranges from 20 to 60 years old. The studied sample was subjected to full ear, nose and throat examinations and audiological evaluation. Depression, Anxiety and Stress Scale (DASS) was developed by Levibond H and Levibond F to assess three self-report scales designed to measure the negative emotional status of depression, anxiety and stress. All patients and control group were evaluated by DASS. (1) Depression: males were affected more than females. All patients over 60 years were affected by depression. The duration of tinnitus seems correlating with the severity of depression. Only 2 patients (4.3 %) of the hearing loss group suffer from depression. (2) Anxiety: 90 % of males suffer from anxiety as compared to 83.3 % females. The age group 20-29 years old suffers more than other age groups. Only 4 patients (8.7 %) of hearing loss group suffer from anxiety. (3) Stress: females seem to be affected by the stress (76.7 %) more than males (67.5). Patients in age group 30-39 suffer the most from the disease. There is a direct correlation between duration of tinnitus and severity of stress. No one of the hearing loss group suffers from stress. In conclusion, depression, anxiety and stress should be taken into consideration in the treatment of patients suffering from tinnitus.

  5. Oxidative Stress Markers and C-Reactive Protein Are Related to Severity of Heart Failure in Patients with Dilated Cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Celina Wojciechowska

    2014-01-01

    Full Text Available Background. The aim of study was to determine relationships between functional capacity (NYHA class, left ventricle ejection fraction (LVEF, hemodynamic parameters, and biomarkers of redox state and inflammation in patients with dilated cardiomyopathy (DCM. Methods. DCM patients (n=109, aged 45.97±10.82 years, NYHA class IIV, and LVEF 2.94±7.1% were studied. Controls comprised age-matched healthy volunteers (n=28. Echocardiography and right heart catheterization were performed. Serum activities of superoxide dismutase isoenzymes (MnSOD and CuZnSOD, concentrations of uric acid (UA, malondialdehyde (MDA, and C-reactive protein (hs-CRP were measured. Results. MnSOD, UA, hs-CRP, and MDA were significantly higher in DCM patients compared to controls. Except MDA concentration, above parameters were higher in patients in III-IV NYHA class or with lower LVEF. hsCRP correlated with of MnSOD (P<0.05 and CuZnSOD activity (P<0.01. Both isoenzymes positively correlated with mPAP and pulmonary capillary wedge pressure (MnSOD, resp., P<0.01 and P<0.05 and CuZnSOD P<0.05; P<0.05. UA positively correlated with MnSOD (P<0.05, mPAP (P<0.05, and PVRI (P<0.05. The negative correlation between LVEF and UA (P<0.01 was detected. Conclusion. There are relationships among the severity of symptoms of heart failure, echocardiographic hemodynamic parameters, oxidative stress, and inflammatory activation. Increased MnSOD activity indicates the mitochondrial source of ROS in patients with advanced heart failure.

  6. Coping strategy and social support modify the association between perceived stress and C-reactive protein: a longitudinal study of healthy men and women.

    Science.gov (United States)

    Shimanoe, Chisato; Hara, Megumi; Nishida, Yuichiro; Nanri, Hinako; Otsuka, Yasuko; Horita, Mikako; Yasukata, Jun; Miyoshi, Nobuyuki; Yamada, Yosuke; Higaki, Yasuki; Tanaka, Keitaro

    2018-05-01

    Inconsistent associations have been reported between perceived stress and C-reactive protein (CRP), a marker of systemic inflammation. We previously observed a male-specific inverse relationship between perceived stress and CRP in a cross-sectional study. In the present study, we examined the longitudinal association between changes in perceived stress and CRP, and further analyzed whether changes in coping strategies and social support modify this association. This study included 8454 participants in both a baseline survey and a follow-up survey 5 years later. Psychosocial measures (i.e. perceived stress, coping strategies, and social support) and CRP concentrations were measured by identical means in both surveys. Consistent with our previous findings, increased perceived stress was significantly associated with lower CRP in men (p trend  = .037), but not in women. Increased "emotional expression," a coping strategy, was also associated with lower CRP in women (p trend  = .024). Furthermore, interactions between perceived stress and a coping strategy (positive reappraisal) or social support on CRP were found in men (p interaction  = .007 and .038, respectively); the above inverse association between stress and CRP was not detected for participants with diminished positive reappraisal or social support. In conclusion, increases in perceived stress during a 5-year period were associated with decreases in CRP among healthy men, and the observed association was possibly modified by coping strategy or social support.

  7. When bad guys become good ones: the key role of reactive oxygen species and nitric oxide in the plant responses to abiotic stress

    Directory of Open Access Journals (Sweden)

    Fernanda Dos Santos Farnese

    2016-04-01

    Full Text Available The natural environment of plants is composed of a complex set of abiotic stresses and their ability to respond to these stresses is highly flexible and finely balanced through the interaction between signaling molecules. In this review, we highlight the integrated action between reactive oxygen species (ROS and reactive nitrogen species (RNS, particularly nitric oxide (NO, involved in the acclimation to different abiotic stresses. Under stressful conditions, the biosynthesis transport and the metabolism of ROS and NO influence plant response mechanisms. The enzymes involved in ROS and NO synthesis and scavenging can be found in different cells compartments and their temporal and spatial locations are determinant for signaling mechanisms. Both ROS and NO are involved in long distances signaling (ROS wave and GSNO transport, promoting an acquired systemic acclimation to abiotic stresses. The mechanisms of abiotic stresses response triggered by ROS and NO involve some general steps, as the enhancement of antioxidant systems, but also stress-specific mechanisms, according to the stress type (drought, hypoxia, heavy metals, etc, and demand the interaction with other signaling molecules, such as MAPK, plant hormones and calcium. The transduction of ROS and NO bioactivity involves post-translational modifications of proteins, particularly S-glutathionylation for ROS, and S-nitrosylation for NO. These changes may alter the activity, stability, and interaction with other molecules or subcellular location of proteins, changing the entire cell dynamics and contributing to the maintenance of homeostasis. However, despite the recent advances about the roles of ROS and NO in signaling cascades, many challenges remain, and future studies focusing on the signaling of these molecules in planta are still necessary.

  8. When Bad Guys Become Good Ones: The Key Role of Reactive Oxygen Species and Nitric Oxide in the Plant Responses to Abiotic Stress.

    Science.gov (United States)

    Farnese, Fernanda S; Menezes-Silva, Paulo E; Gusman, Grasielle S; Oliveira, Juraci A

    2016-01-01

    The natural environment of plants is composed of a complex set of abiotic stresses and their ability to respond to these stresses is highly flexible and finely balanced through the interaction between signaling molecules. In this review, we highlight the integrated action between reactive oxygen species (ROS) and reactive nitrogen species (RNS), particularly nitric oxide (NO), involved in the acclimation to different abiotic stresses. Under stressful conditions, the biosynthesis transport and the metabolism of ROS and NO influence plant response mechanisms. The enzymes involved in ROS and NO synthesis and scavenging can be found in different cells compartments and their temporal and spatial locations are determinant for signaling mechanisms. Both ROS and NO are involved in long distances signaling (ROS wave and GSNO transport), promoting an acquired systemic acclimation to abiotic stresses. The mechanisms of abiotic stresses response triggered by ROS and NO involve some general steps, as the enhancement of antioxidant systems, but also stress-specific mechanisms, according to the stress type (drought, hypoxia, heavy metals, etc.), and demand the interaction with other signaling molecules, such as MAPK, plant hormones, and calcium. The transduction of ROS and NO bioactivity involves post-translational modifications of proteins, particularly S-glutathionylation for ROS, and S-nitrosylation for NO. These changes may alter the activity, stability, and interaction with other molecules or subcellular location of proteins, changing the entire cell dynamics and contributing to the maintenance of homeostasis. However, despite the recent advances about the roles of ROS and NO in signaling cascades, many challenges remain, and future studies focusing on the signaling of these molecules in planta are still necessary.

  9. Social Anxiety-Linked Attention Bias to Threat Is Indirectly Related to Post-Event Processing Via Subjective Emotional Reactivity to Social Stress.

    Science.gov (United States)

    Çek, Demet; Sánchez, Alvaro; Timpano, Kiara R

    2016-05-01

    Attention bias to threat (e.g., disgust faces) is a cognitive vulnerability factor for social anxiety occurring in early stages of information processing. Few studies have investigated the relationship between social anxiety and attention biases, in conjunction with emotional and cognitive responses to a social stressor. Elucidating these links would shed light on maintenance factors of social anxiety and could help identify malleable treatment targets. This study examined the associations between social anxiety level, attention bias to disgust (AB-disgust), subjective emotional and physiological reactivity to a social stressor, and subsequent post-event processing (PEP). We tested a mediational model where social anxiety level indirectly predicted subsequent PEP via its association with AB-disgust and immediate subjective emotional reactivity to social stress. Fifty-five undergraduates (45% female) completed a passive viewing task. Eye movements were tracked during the presentation of social stimuli (e.g., disgust faces) and used to calculate AB-disgust. Next, participants gave an impromptu speech in front of a video camera and watched a neutral video, followed by the completion of a PEP measure. Although there was no association between AB-disgust and physiological reactivity to the stressor, AB-disgust was significantly associated with greater subjective emotional reactivity from baseline to the speech. Analyses supported a partial mediation model where AB-disgust and subjective emotional reactivity to a social stressor partially accounted for the link between social anxiety levels and PEP. Copyright © 2016. Published by Elsevier Ltd.

  10. Research on fatigue behavior and residual stress of large-scale cruciform welding joint with groove

    International Nuclear Information System (INIS)

    Zhao, Xiaohui; Liu, Yu; Liu, Yong; Gao, Yuan

    2014-01-01

    Highlights: • The fatigue behavior of the large-scale cruciform welding joint with groove was studied. • The longitudinal residual stress of the large-scale cruciform welding joint was tested by contour method. • The fatigue fracture mechanism of the large-scale cruciform welding joint with groove was analyzed. - Abstract: Fatigue fracture behavior of the 30 mm thick Q460C-Z steel cruciform welded joint with groove was investigated. The fatigue test results indicated that fatigue strength of 30 mm thick Q460C-Z steel cruciform welded joint with groove can reach fatigue level of 80 MPa (FAT80). Fatigue crack source of the failure specimen initiated from weld toe. Meanwhile, the microcrack was also found in the fusion zones of the fatigue failure specimen, which was caused by weld quality and weld metal integrity resulting from the multi-pass welds. Two-dimensional map of the longitudinal residual stress of 30 mm thick Q460C-Z steel cruciform welded joint with groove was obtained by using the contour method. The stress nephogram of Two-dimensional map indicated that longitudinal residual stress in the welding center is the largest

  11. Reliability and validity of Persian version of perceived stress scale (PSS-10) in adults with asthma.

    Science.gov (United States)

    Maroufizadeh, Saman; Zareiyan, Armin; Sigari, Naseh

    2014-05-01

    Asthma is a major public health problem in the world, and recent findings suggest that stress influences asthma and asthma morbidity. The 10-item Perceived Stress Scale (PSS-10) is one of the most frequently used instruments to measure psychological stress. This study was conducted to evaluate the psychometric properties of the Persian versions of the PSS-10 in adults with asthma. In this descriptive cross-sectional study as a methodological research, 106 asthmatic patients referring to several clinics in Sanandaj (western Iran) were selected through convenience sampling. The PSS-10 and the 21-item Depression anxiety and stress scale (DASS-21) were administrated to all patients. Cronbach's alpha was used to evaluate reliability of PSS-10, and confirmatory factor analysis (CFA) and convergent validity were used to evaluate its validity. The results of confirmatory factor analysis indicated that a two-factor structure of PSS-10 provided a good fit to data. The Cronbach's alpha coefficients for negative factor, positive factor and total score (PSS-10) were 0.86, 0.83, and 0.90, respectively. The PSS-10 was positively correlated with the DASS-21 and its subscales, indicating an acceptable convergent validity. Female asthmatic patients scored higher on PSS-10 in comparison with male asthmatic patients. The Persian version of PSS-10 is a valid and reliable instrument to measure perceived stress in adults with asthma.

  12. [Two scales for job stress and psychological health investigation: type-A personality and job satisfaction].

    Science.gov (United States)

    Batigün, Ayşegül Durak; Sahin, Nesrin H

    2006-01-01

    The purpose of the present study is to investigate the psychometric properties of two instruments developed to measure Type-A behaviors and job satisfaction, two important variables mentioned in the stress literature. The data were collected from two different samples, one composed of 426 bank personnel, the other composed of 94 adults working in a private company. The findings are presented separately under the titles Study I and Study II. In both of the studies the assessment instruments used were: Stress Audit (Symptoms), Stress Audit (Vulnerability), Stress Coping Behaviors, Job Satisfaction Scale, and Type-A Behaviors Inventory. For both of the instruments, the studies were based on factor analyses. For Type-A Behaviors Inventory the analyses revealed 4 factors, while for Job Satisfaction Scale they revealed 6 factors. The factor subscales developed from these factors were found to have satisfactory Cronbach's alphas. For Type-A Behaviors Inventory they ranged between .40 and .90; whereas for Job Satisfaction Inventory these values were between .53 and .94. Both studies also included correlational analyses to specify the criterion validity values of the two instruments. The findings revealed that both of the instruments had satisfactory psychometric values, indicating that they can be reliably used in health psychology and job stress studies.

  13. [Depression, anxiety and stress scales: DASS--A screening procedure not only for pain patients].

    Science.gov (United States)

    Nilges, P; Essau, C

    2015-12-01

    The assessment of mental distress is a central aspect in pain research and treatment. Particularly for depression the comorbidity with pain poses methodological and conceptual challenges. This study examined the psychometric properties of the short version of the depression, anxiety and stress scale (DASS), used in both pain research and treatment and constructed to overcome the particular problems by omitting somatic items and concentrating on the psychological core aspects of depression, anxiety and stress. The psychometric properties of the DASS-21 were compared between patients with pain and various people without any pain problems (N = 950). The DASS has three subscales, depression, anxiety and stress, each with seven items. The construct validity of the DASS was examined using the hospital anxiety and depression scale (HADS) for anxiety and depression and the general depression scale (Allgemeine Depressionsskala, ADS) for depression. The sensitivity and specificity for depression were determined against a structured interview for diagnostic and statistical manual of mental disorders (DSM-IV) and compared with the Center for Epidemiological Studies depression scale (CESD) and HADS in pain patients. Cronbach's alpha of the DASS for the depression subscale was at least 0.91, while the anxiety and stress subscales had Cronbach alphas of 0.78-0.82 and 0.81-0.89, respectively. Although the depression subscale has only 7 items, it is just as reliable as the ADS with 21 items. It also has a better sensitivity and specificity than the HADS in identifying clinical patients with depression. The DASS is a reliable questionnaire, free to use and brief to administer; therefore, it is an alternative to the previously used instruments for the screening of depression. Furthermore, the subscale stress measures irritability and tension, which are important aspects of pain experience but underused in assessment procedures for the diagnosis and treatment evaluation of patients

  14. Reliability and validity analysis of modified Nursing Stress Scale for Indian population.

    Science.gov (United States)

    Pathak, Vasundhara; Chakraborty, Tania; Mukhopadhyay, Suman

    2013-01-01

    The original Nursing Stress Scale (NSS) was structurally modified according to results of factorial analysis and a new scale was named as modified nursing stress scale (MNSS). This is the first study to modify and validate NSS for Indian nursing population. Factorial analysis showed different factor loading for two subscales and items were shifted according to their loading to provide a more meaningful structure. After relocation of Items 13, 14, and 15 into first factor, this factor was renamed as "emotional and painful conditions of patients" to provide a more appropriate name to the first factor. Items 24, 25, 26, 27, 28, and 29 were found to be distributed under two different factors; one of these two was renamed as "unpredictable changes" and another retained its original name (i.e., workload). This distribution was also supported by rational analysis. All other items were distributed under factors as in the original scale. Rest of the validity assessment was done with the modified scale. Thus, with minor changes in structure, the scale was found to have better content validity.

  15. Nanoscale Roughness of Faults Explained by the Scale-Dependent Yield Stress of Geologic Materials

    Science.gov (United States)

    Thom, C.; Brodsky, E. E.; Carpick, R. W.; Goldsby, D. L.; Pharr, G.; Oliver, W.

    2017-12-01

    Despite significant differences in their lithologies and slip histories, natural fault surfaces exhibit remarkably similar scale-dependent roughness over lateral length scales spanning 7 orders of magnitude, from microns to tens of meters. Recent work has suggested that a scale-dependent yield stress may result in such a characteristic roughness, but experimental evidence in favor of this hypothesis has been lacking. We employ an atomic force microscope (AFM) operating in intermittent-contact mode to map the topography of the Corona Heights fault surface. Our experiments demonstrate that the Corona Heights fault exhibits isotropic self-affine roughness with a Hurst exponent of 0.75 +/- 0.05 at all wavelengths from 60 nm to 10 μm. If yield stress controls roughness, then the roughness data predict that yield strength varies with length scale as λ-0.25 +/ 0.05. To test the relationship between roughness and yield stress, we conducted nanoindentation tests on the same Corona Heights sample and a sample of the Yair Fault, a carbonate fault surface that has been previously characterized by AFM. A diamond Berkovich indenter tip was used to indent the samples at a nominally constant strain rate (defined as the loading rate divided by the load) of 0.2 s-1. The continuous stiffness method (CSM) was used to measure the indentation hardness (which is proportional to yield stress) and the elastic modulus of the sample as a function of depth in each test. For both samples, the yield stress decreases with increasing size of the indents, a behavior consistent with that observed for many engineering materials and recently for other geologic materials such as olivine. The magnitude of this "indentation size effect" is best described by a power-law with exponents of -0.12 +/- 0.06 and -0.18 +/- 0.08 for the Corona Heights and Yair Faults, respectively. These results demonstrate a link between surface roughness and yield stress, and suggest that fault geometry is the physical

  16. Discriminating Malingered from Genuine Civilian Posttraumatic Stress Disorder: A Validation of Three MMPI-2 Infrequency Scales (F, Fp, and Fptsd)

    Science.gov (United States)

    Elhai, Jon D.; Naifeh, James A.; Zucker, Irene S.; Gold, Steven N.; Deitsch, Sarah E.; Frueh, B. Christopher

    2004-01-01

    The Infrequency-Posttraumatic Stress Disorder scale (Fptsd), recently created for the Minnesota Multiphasic Personality Inventory-2 (MMPI-2), has demonstrated incremental validity over other MMPI-2 scales in malingered posttraumatic stress disorder (PTSD) detection. Fptsd was developed with combat-exposed PTSD patients, potentially limiting its…

  17. A bHLH gene from Tamarix hispida improves abiotic stress tolerance by enhancing osmotic potential and decreasing reactive oxygen species accumulation.

    Science.gov (United States)

    Ji, Xiaoyu; Nie, Xianguang; Liu, Yujia; Zheng, Lei; Zhao, Huimin; Zhang, Bing; Huo, Lin; Wang, Yucheng

    2016-02-01

    Basic helix-loop-helix (bHLH) leucine-zipper transcription factors play important roles in abiotic stress responses. However, their specific roles in abiotic stress tolerance are not fully known. Here, we functionally characterized a bHLH gene, ThbHLH1, from Tamarix hispida in abiotic stress tolerance. ThbHLH1 specifically binds to G-box motif with the sequence of 'CACGTG'. Transiently transfected T. hispida plantlets with transiently overexpressed ThbHLH1 and RNAi-silenced ThbHLH1 were generated for gain- and loss-of-function analysis. Transgenic Arabidopsis thaliana lines overexpressing ThbHLH1 were generated to confirm the gain- and loss-of-function analysis. Overexpression of ThbHLH1 significantly elevates glycine betaine and proline levels, increases Ca(2+) concentration and enhances peroxidase (POD) and superoxide dismutase (SOD) activities to decrease reactive oxygen species (ROS) accumulation. Additionally, ThbHLH1 regulates the expression of the genes including P5CS, BADH, CaM, POD and SOD, to activate the above physiological changes, and also induces the expression of stress tolerance-related genes LEAs and HSPs. These data suggest that ThbHLH1 induces the expression of stress tolerance-related genes to improve abiotic stress tolerance by increasing osmotic potential, improving ROS scavenging capability and enhancing second messenger in stress signaling cascades. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  18. Study on the effect of reactive oxygen species-mediated oxidative stress on the activation of mitochondrial apoptosis and the tenderness of yak meat.

    Science.gov (United States)

    Wang, Lin-Lin; Yu, Qun-Li; Han, Ling; Ma, Xiu-Li; Song, Ren-De; Zhao, Suo-Nan; Zhang, Wen-Hua

    2018-04-01

    This study investigated the effect of reactive oxygen species-mediated oxidative stress on activation of mitochondrial apoptosis and tenderness of yak meat during postmortem ageing. Oxidative stress degree, Ca 2+ levels, membrane permeability transition pore opening, mitochondrial membrane potential, apoptotic factors and the shear force were examined. Results showed that the ROS generated by H 2 O 2 significantly increased mitochondrial oxidative stress by decreasing the activities of superoxide dismutase, catalase and glutathione peroxidase, and increasing lipid peroxidation. Furthermore, oxidative stress enhanced Ca 2+ production and cytochrome c release, changed the levels of Bcl-2 family proteins and activated caspase-9 and -3 activities. Ultimately, oxidative stress increased the apoptosis rate and tenderness of yak meat. These observations confirmed that ROS-mediated oxidative stress participates in the activation of the apoptotic cascade reaction involving Ca 2+ and Bcl-2 family proteins. The results further suggested that ROS-mediated oxidative stress plays a significant role in meat tenderization through the mitochondrial apoptotic pathway. Copyright © 2017. Published by Elsevier Ltd.

  19. Reliability and validity of the Perceived Stress Scale-10 in Hispanic Americans with English or Spanish language preference.

    Science.gov (United States)

    Baik, Sharon H; Fox, Rina S; Mills, Sarah D; Roesch, Scott C; Sadler, Georgia Robins; Klonoff, Elizabeth A; Malcarne, Vanessa L

    2017-01-01

    This study examined the psychometric properties of the Perceived Stress Scale-10 among 436 community-dwelling Hispanic Americans with English or Spanish language preference. Multigroup confirmatory factor analysis examined the factorial invariance of the Perceived Stress Scale-10 across language groups. Results supported a two-factor model (negative, positive) with equivalent response patterns and item intercepts but different factor covariances across languages. Internal consistency reliability of the Perceived Stress Scale-10 total and subscale scores was good in both language groups. Convergent validity was supported by expected relationships of Perceived Stress Scale-10 scores to measures of anxiety and depression. These results support the use of the Perceived Stress Scale-10 among Hispanic Americans.

  20. Residual stress measurement of large scaled welded pipe using neutron diffraction method. Effect of SCC crack propagation and repair weld on residual stress distribution

    International Nuclear Information System (INIS)

    Suzuki, Hiroshi; Katsuyama, Jinya; Tobita, Tohru; Morii, Yukio

    2011-01-01

    The RESA-1 neutron engineering diffractometer in the JRR-3 (Japan Research Reactor No.3) at the Japan Atomic Energy Agency, which is used for stress measurements, was upgraded to realize residual stress measurements of large scaled mechanical components. A series of residual stress measurements was made to obtain through-thickness residual stress distributions in a Type 304 stainless steel butt-welded pipe of 500A-sch.80 using the upgraded RESA-1 diffractometer. We evaluated effects of crack propagation such as stress corrosion cracking (SCC) and a part-circumference repair weld on the residual stress distributions induced by girth welding. Measured residual stress distributions near original girth weld revealed good agreement with typical results shown in some previous works using finite element method, deep hole drilling as well as neutron diffraction. After introducing a mock crack with 10 mm depth in the heat affected zone on the inside wall of the pipe by electro discharge machining, the axial residual stresses were found to be released in the part of the mock crack. However, changes in the through-wall bending stress component and the self-equilibrated stress component were negligible and hence the axial residual stress distribution in the ligament was remained in the original residual stresses near girth weld without the mock crack. Furthermore, changes in hoop and radial residual stress were also small. The residual stress distributions after a part repair welding on the outer circumference of the girth weld were significantly different from residual stress distributions near the original girth weld. The through-thickness average axial residual stress was increased due to increase of the tensile membrane stress and mitigation of the bending stress after repair welding. Throughout above studies, we evidenced that the neutron diffraction technique is useful and powerful tool for measuring residual stress distributions in large as well as thick mechanical

  1. Genome-scale cold stress response regulatory networks in ten Arabidopsis thaliana ecotypes

    DEFF Research Database (Denmark)

    Barah, Pankaj; Jayavelu, Naresh Doni; Rasmussen, Simon

    2013-01-01

    available from Arabidopsis thaliana 1001 genome project, we further investigated sequence polymorphisms in the core cold stress regulon genes. Significant numbers of non-synonymous amino acid changes were observed in the coding region of the CBF regulon genes. Considering the limited knowledge about......BACKGROUND: Low temperature leads to major crop losses every year. Although several studies have been conducted focusing on diversity of cold tolerance level in multiple phenotypically divergent Arabidopsis thaliana (A. thaliana) ecotypes, genome-scale molecular understanding is still lacking....... RESULTS: In this study, we report genome-scale transcript response diversity of 10 A. thaliana ecotypes originating from different geographical locations to non-freezing cold stress (10°C). To analyze the transcriptional response diversity, we initially compared transcriptome changes in all 10 ecotypes...

  2. Depression Anxiety and Stress Scales (DASS-21): psychometric analysis across four racial groups.

    Science.gov (United States)

    Norton, Peter J

    2007-09-01

    Growing cross-cultural awareness has led researchers to examine frequently used research instruments and assessment tools in racially diverse populations. The present study was conducted to assess the psychometric characteristics of the 21-item version of the Depression, Anxiety, and Stress Scales (DASS-21) among different racial groups. The DASS-21 was chosen because it appears to be a reliable and easy to administer measure, ideal for both clinical and research purposes. Results suggest that the internal consistency, and convergent and divergent validity of the DASS-21 are similar across racial groups. Multigroup CFA, however, indicated that item loadings were invariant, while scale covariances were not invariant. This suggests that, although the items may load similarly on the depression, anxiety and stress constructs, these constructs may be differentially inter-related across groups. Implications for application in clinical practice are discussed.

  3. Depression Anxiety Stress Scale: is it valid for children and adolescents?

    Science.gov (United States)

    Patrick, Jeff; Dyck, Murray; Bramston, Paul

    2010-09-01

    The Depression Anxiety Stress Scale (Lovibond & Lovibond, 1995) is used to assess the severity of symptoms in child and adolescent samples although its validity in these populations has not been demonstrated. The authors assessed the latent structure of the 21-item version of the scale in samples of 425 and 285 children and adolescents on two occasions, one year apart. On each occasion, parallel analyses suggested that only one component should be extracted, indicating that the test does not differentiate depression, anxiety, and stress in children and adolescents. The results provide additional evidence that adult models of depression do not describe the experience of depression in children and adolescents. (c) 2010 Wiley Periodicals, Inc.

  4. Psychometric properties and validation of Nepali version of the Depression Anxiety Stress Scales (DASS-21).

    Science.gov (United States)

    Tonsing, Kareen N

    2014-04-01

    This study investigated the reliability of the Nepali version of the 21-item Depression Anxiety Stress Scale (DASS-21) among non-clinical sample. The purpose of this paper is to report the dimensionality and internal consistency of the DASS-21in a sample of non-clinical adults. This study was conducted in Hong Kong among 212 Nepali adults, aged 18-60 years. Life satisfaction was assessed with the Life Satisfaction Scale. The dimensionality of the DASS-21 scale was investigated using exploratory factor analysis. Construct validity was evaluated using the life satisfaction scale. The intercorrelation among depression, anxiety and stress subscales indicates that symptoms of psychological distress as measured by the DASS-21-N can distinguished between the three constructs in adult community sample. The results also showed inverse correlation among DASS-21-N and life satisfaction scale, supporting the assumption that the higher the life satisfaction, the lower the psychological distress. The results of this study indicate that the Nepali version of the DASS-21 demonstrate adequate psychometric properties in relation to internal consistency and validity, lending support to prior studies and suggest that the DASS-21 can be utilized among diverse groups with confidence. It supports the reliability of the 3-factorial dimensionality of the DASS-21, and highlight that it is a valid and useful tool that can distinguish between depression and anxiety. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Effects of interpersonal violence-related post-traumatic stress disorder (PTSD) on mother and child diurnal cortisol rhythm and cortisol reactivity to a laboratory stressor involving separation.

    Science.gov (United States)

    Cordero, Maria I; Moser, Dominik A; Manini, Aurelia; Suardi, Francesca; Sancho-Rossignol, Ana; Torrisi, Raffaella; Rossier, Michel F; Ansermet, François; Dayer, Alexandre G; Rusconi-Serpa, Sandra; Schechter, Daniel S

    2017-04-01

    Women who have experienced interpersonal violence (IPV) are at a higher risk to develop posttraumatic stress disorder (PTSD), with dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis and impaired social behavior. Previously, we had reported impaired maternal sensitivity and increased difficulty in identifying emotions (i.e. alexithymia) among IPV-PTSD mothers. One of the aims of the present study was to examine maternal IPV-PTSD salivary cortisol levels diurnally and reactive to their child's distress in relation to maternal alexithymia. Given that mother-child interaction during infancy and early childhood has important long-term consequences on the stress response system, toddlers' cortisol levels were assessed during the day and in response to a laboratory stressor. Mothers collected their own and their 12-48month-old toddlers' salivary samples at home three times: 30min after waking up, between 2-3pm and at bedtime. Moreover, mother-child dyads participated in a 120-min laboratory session, consisting of 3 phases: baseline, stress situation (involving mother-child separation and exposure to novelty) and a 60-min regulation phase. Compared to non-PTSD controls, IPV-PTSD mothers - but not their toddlers, had lower morning cortisol and higher bedtime cortisol levels. As expected, IPV-PTSD mothers and their children showed blunted cortisol reactivity to the laboratory stressor. Maternal cortisol levels were negatively correlated to difficulty in identifying emotions. Our data highlights PTSD-IPV-related alterations in the HPA system and its relevance to maternal behavior. Toddlers of IPV-PTSD mothers also showed an altered pattern of cortisol reactivity to stress that potentially may predispose them to later psychological disorders. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Time-variable stress transfer across a megathrust from seismic to Wilson cycle scale

    Science.gov (United States)

    Rosenau, Matthias; Angiboust, Samuel; Moreno, Marcos; Schurr, Bernd; Oncken, Onno

    2013-04-01

    During the lifetime of a convergent plate margin stress transfer across the plate interface (a megathrust) can be expected to vary at multiple timescales. At short time scales (years to decades), a subduction megathrust interface appears coupled (accumulating shear stress) at shallow depth (seismogenic zone proportional to effective normal load but also to relative shear stress. For areas of near complete stress drop locking might systematically decrease over the interseismic period from >80-95 % shortly after an earthquake to backslip at significant fractions of plate convergence rate (non-volcanic tremor and slow slip below the seismogenic zone represent short term episodes of metamorphic fluid infiltration into the shallow megathrust. A megathrust fault valve mechanism clocked by the greatest earthquakes then accounts for cyclic fluid pressure build up and drainage at sub-seismic cycle scale. As pore pressure dynamics are controlled primarily by permeability which in turn is controlled by structure and material properties, then more long term coupling transients associated with structural evolution of the plate margin can be implied. Fluid controlled transients might interfere with transients and secular trends resulting from changes in material strength and plate tectonic forces over the Wilson cycle resulting in a multispectral stress-transfer pattern associated with convergent margin evolution. Because of the viscous damping effect of the underlying asthenosphere, however, only longterm transients (periods >1-10 ka) are transmitted into the engaged plates. We therefore speculate that the multispectral nature of stress transfer across a megathrust filtered through the asthenosphere explains transient fault activity in some intraplate settings.

  7. At-risk and intervention thresholds of occupational stress using a visual analogue scale

    Science.gov (United States)

    Pereira, Bruno; Moustafa, Farès; Naughton, Geraldine; Lesage, François-Xavier; Lambert, Céline

    2017-01-01

    Background The visual analogue scale (VAS) is widely used in clinical practice by occupational physicians to assess perceived stress in workers. However, a single cut-off (black-or-white decision) inadequately discriminates between workers with and without stress. We explored an innovative statistical approach to distinguish an at-risk population among stressed workers, and to establish a threshold over which an action is urgently required, via the use of two cut-offs. Methods Participants were recruited during annual work medical examinations by a random sample of workers from five occupational health centres. We previously proposed a single cut-off of VAS stress in comparison with the Perceived Stress Scale (PSS14). Similar methodology was used in the current study, along with a gray zone approach. The lower limit of the gray zone supports sensitivity (“at-risk” threshold; interpreted as requiring closer surveillance) and the upper limit supports specificity (i.e. “intervention” threshold–emergency action required). Results We included 500 workers (49.6% males), aged 40±11 years, with a PSS14 score of 3.8±1.4 and a VAS score of 4.0±2.4. Using a receiver operating characteristic curve and the PSS cut-off score of 7.2, the optimal VAS threshold was 6.8 (sensitivity = 0.89, specificity = 0.87). The lower and upper thresholds of the gray zone were 5 and 8.2, respectively. Conclusions We identified two clinically relevant cut-offs on the VAS of stress: a first cut-off of 5.0 for an at-risk population, and a second cut-off of 8.2 over which an action is urgently required. Future investigations into the relationships between this upper threshold and deleterious events are required. PMID:28586383

  8. Energy and Environmental Drivers of Stress and Conflict in Multi scale Models of Human Social Behavior

    Science.gov (United States)

    2017-10-31

    resolved by the recognition that cities are first and foremost self- organizing social networks embedded in space and enabled by urban infrastructure and...AUTHORS 7. PERFORMING ORGANIZATION NAMES AND ADDRESSES 15. SUBJECT TERMS b. ABSTRACT 2. REPORT TYPE 17. LIMITATION OF ABSTRACT 15. NUMBER OF PAGES 5d...Report: Energy and Environmental Drivers of Stress and Conflict in Multi-scale Models of Human Social Behavior The views, opinions and/or findings

  9. Adaptation and validation of the depression, anxiety and stress scale (DASS) to Brazilian Portuguese.

    Science.gov (United States)

    Vignola, Rose Claudia Batistelli; Tucci, Adriana Marcassa

    2014-02-01

    Depression and anxiety have been associated with a range of symptoms that often overlap. Depression, Anxiety and Stress Scale-21 (DASS-21) is a single instrument to assess symptoms of depression, anxiety and stress. This study aimed to adapt and validate the DASS-21 for use in the Brazilian Portuguese language. The DASS-21 has been adapted following the translation-back translation methodology from English to Portuguese. 242 subjects completed the following assessments: the DASS-21, the Beck Depression Index (BDI), Beck Anxiety Index (BAI) and the Inventory of Stress Symptoms of Lipp (ISSL). The Kaiser-Meyer-Olkin (KMO) result was .949, indicating that the adequacy of the model was high. Cronbach's alpha was .92 for the depression, .90 for the stress, and .86 for the anxiety, indicating a good internal consistency for each subscale. The correlations between DASS scale and BDI scale, BAI scale and ISSL inventory were strong. The factorial analysis and distribution of factors among the subscales indicated that the structure of three distinct factors is adequate. Older subjects over 65 years of age were not largely represented in this sample. A study specific to this elderly population should be conducted. Another limitation of the study was education level. The impact of low education in its applicability should be considered. The findings support the validity of the Brazilian Portuguese version of the DASS-21 and add to the evidence of the DASS-21 quality and ability to assess emotional states separately, eliminating the use of different instruments to assess these states. © 2013 Published by Elsevier B.V.

  10. Psychometric evaluation of the Nursing Stress Scale (NSS) among Chinese nurses in Taiwan.

    Science.gov (United States)

    Lee, Mei-Hua; Holzemer, William L; Faucett, Julia

    2007-01-01

    The purpose of this study was to translate the Nursing Stress Scale (NSS) into Chinese and test its reliability and validity among Chinese nurses in Taiwan. Potential participants were asked to self-administer a Chinese version of the NSS. The agreement estimation was used to determine the equivalence of the meaning between the Chinese and original English versions and was rated by five bilingual nurses as 92% accurate for the 34 items. The test-retest reliability for the NSS at 2 weeks was .71 (p = .022, n=10). Internal consistency reliability and factor analysis were tested with 770 nurses from 65 inpatient units at a medical center in Taiwan. The internal consistency of the Chinese version of the NSS for an overall coefficient alpha is .91 for the total scale, and ranges from .67 to .79 for the subscales. The Chinese version of the NSS explains 53.77% of the variance in work stressors among Chinese nurses in Taiwan. Overall, the Chinese version of the NSS is internally consistent but may not be stable over 2 weeks. There was adequate evidence of the reliability and validity of the NSS-Chinese as an instrument appropriate to measure work stress among Chinese nurses. The translated NSS could be a useful tool for examining the frequency and major sources of stress experienced by Chinese nurses in hospital settings, and for the development of appropriate interventions for stress reduction.

  11. Development of the Seasonal Migrant Agricultural Worker Stress Scale in Sanliurfa, Southeast Turkey.

    Science.gov (United States)

    Simsek, Zeynep; Ersin, Fatma; Kirmizitoprak, Evin

    2016-01-01

    Stress is one of the main causes of health problems, especially mental disorders. These health problems cause a significant amount of ability loss and increase cost. It is estimated that by 2020, mental disorders will constitute 15% of the total disease burden, and depression will rank second only after ischemic heart disease. Environmental experiences are paramount in increasing the liability of mental disorders in those who constantly face sustained high levels of stress. The objective of this study was to develop a stress scale for seasonal migrant agricultural workers aged 18 years and older. The sample consisted of 270 randomly selected seasonal migrant agricultural workers. The average age of the participants was 33.1 ± 14, and 50.7% were male. The Cronbach alpha coefficient and test-retest methods were used for reliability analyses. Although the factor analysis was performed for the structure validity of the scale, the Kaiser-Meyer-Olkin coefficient and Bartlett test were used to determine the convenience of the data for the factor analysis. In the reliability analyses, the Cronbach alpha coefficient of internal consistency was calculated as .96, and the test-retest reliability coefficient was .81. In the exploratory factor analysis for validity of the scale, four factors were obtained, and the factors represented workplace physical conditions (25.7% of the total variance), workplace psychosocial and economic factors (19.3% of the total variance), workplace health problems (15.2% of the total variance), and school problems (10.1% of the total variance). The four factors explained 70.3% of the total variance. As a result of the expert opinions and analyses, a stress scale with 48 items was developed. The highest score to be obtained from the scale was 144, and the lowest score was 0. The increase in the score indicates the increase in the stress levels. The findings show that the scale is a valid and reliable assessment instrument that can be used in

  12. Evaluation of salivary oxidate stress biomarkers, nitric oxide and C-reactive protein in patients with oral lichen planus and burning mouth syndrome.

    Science.gov (United States)

    Tvarijonaviciute, Asta; Aznar-Cayuela, Cristina; Rubio, Camila P; Ceron, José J; López-Jornet, Pia

    2017-05-01

    The aim of this study was to evaluate oxidative stress factors and C-reactive protein in the saliva of patients with oral lichen planus (OLP) and burning mouth syndrome (BMS). This consecutive, cross-sectional study included 20 patients with OLP, 19 with burning mouth syndrome (BMS), and 31 control subjects. The oral cavity of each patient was examined and patients responded to a quality of life questionnaire (OHIP-14) and the xerostomia inventory. The following parameters were measured in whole non-stimulated saliva: trolox equivalent antioxidant capacity (TEAC); total antioxidant capacity (TAC); cupric reducing antioxidant capacity (CUPRAC); ferric reducing ability of plasma (FRAP); C-reactive protein (CRP); nitric oxide; nitrates; and nitrites. The OLP group presented statistically significant differences in reactive oxygen species (ROS) (29 600 cps) in comparison with the control group (39 679 cps) (P < 0.05). In the BMS group, ROS was 29 707 cps with significant difference in comparison with the control group (P < 0.05). Significantly higher salivary nitric oxide (145.7 μmol) and nitrite (141.0 μmol) levels were found in OLP patients in comparison with control group (P < 0.05). Increases in nitric oxide and C-reactive protein were found in the saliva of OLP patients in comparison with BMS and control patients. Further studies are required to confirm these findings. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. ROSMETER: a bioinformatic tool for the identification of transcriptomic imprints related to reactive oxygen species type and origin provides new insights into stress responses.

    Science.gov (United States)

    Rosenwasser, Shilo; Fluhr, Robert; Joshi, Janak Raj; Leviatan, Noam; Sela, Noa; Hetzroni, Amotz; Friedman, Haya

    2013-10-01

    The chemical identity of the reactive oxygen species (ROS) and its subcellular origin will leave a specific imprint on the transcriptome response. In order to facilitate the appreciation of ROS signaling, we developed a tool that is tuned to qualify this imprint. Transcriptome data from experiments in Arabidopsis (Arabidopsis thaliana) for which the ROS type and organelle origin are known were compiled into indices and made accessible by a Web-based interface called ROSMETER. The ROSMETER algorithm uses a vector-based algorithm to portray the ROS signature for a given transcriptome. The ROSMETER platform was applied to identify the ROS signatures profiles in transcriptomes of senescing plants and of those exposed to abiotic and biotic stresses. An unexpected highly significant ROS transcriptome signature of mitochondrial stress was detected during the early presymptomatic stages of leaf senescence, which was accompanied by the specific oxidation of mitochondria-targeted redox-sensitive green fluorescent protein probe. The ROSMETER analysis of diverse stresses revealed both commonalties and prominent differences between various abiotic stress conditions, such as salt, cold, ultraviolet light, drought, heat, and pathogens. Interestingly, early responses to the various abiotic stresses clustered together, independent of later responses, and exhibited negative correlations to several ROS indices. In general, the ROS transcriptome signature of abiotic stresses showed limited correlation to a few indices, while biotic stresses showed broad correlation with multiple indices. The ROSMETER platform can assist in formulating hypotheses to delineate the role of ROS in plant acclimation to environmental stress conditions and to elucidate the molecular mechanisms of the oxidative stress response in plants.

  14. Large scale structures in a turbulent boundary layer and their imprint on wall shear stress

    Science.gov (United States)

    Pabon, Rommel; Barnard, Casey; Ukeiley, Lawrence; Sheplak, Mark

    2015-11-01

    Experiments were performed on a turbulent boundary layer developing on a flat plate model under zero pressure gradient flow. A MEMS differential capacitive shear stress sensor with a 1 mm × 1 mm floating element was used to capture the fluctuating wall shear stress simultaneously with streamwise velocity measurements from a hot-wire anemometer traversed in the wall normal direction. Near the wall, the peak in the cross correlation corresponds to an organized motion inclined 45° from the wall. In the outer region, the peak diminishes in value, but is still significant at a distance greater than half the boundary layer thickness, and corresponds to a structure inclined 14° from the wall. High coherence between the two signals was found for the low-frequency content, reinforcing the belief that large scale structures have a vital impact on wall shear stress. Thus, estimation of the wall shear stress from the low-frequency velocity signal will be performed, and is expected to be statistically significant in the outer boundary layer. Additionally, conditionally averaged mean velocity profiles will be presented to assess the effects of high and low shear stress. This material is based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1315138.

  15. Wafer scale lead zirconate titanate film preparation by sol-gel method using stress balance layer

    International Nuclear Information System (INIS)

    Lu Jian; Kobayashi, Takeshi; Yi Zhang; Maeda, Ryutaro; Mihara, Takashi

    2006-01-01

    In this paper, platinum/titanium (Pt/Ti) film was introduced as a residual stress balance layer into wafer scale thick lead zirconate titanate (PZT) film fabrication by sol-gel method. The stress developing in PZT film's bottom electrode as well as in PZT film itself during deposition were analyzed; the wafer curvatures, PZT crystallizations and PZT electric properties before and after using Pt/Ti stress balance layer were studied and compared. It was found that this layer is effective to balance the residual stress in PZT film's bottom electrode induced by thermal expansion coefficient mismatch and Ti diffusion, thus can notably reduce the curvature of 4-in. wafer from - 40.5 μm to - 12.9 μm after PZT film deposition. This stress balance layer was also found effective to avoid the PZT film cracking even when annealed by rapid thermal annealing with heating-rate up to 10.5 deg. C/s. According to X-ray diffraction analysis and electric properties characterization, crack-free uniform 1-μm-thick PZT film with preferred pervoskite (001) orientation, excellent dielectric constant, as high as 1310, and excellent remanent polarization, as high as 39.8 μC/cm 2 , can be obtained on 4-in. wafer

  16. Factor structure and validity of the Depression, Anxiety and Stress Scale-21 in Swedish translation.

    Science.gov (United States)

    Alfonsson, S; Wallin, E; Maathz, P

    2017-03-01

    WHAT IS KNOWN ON THE SUBJECT?: The Depression, Anxiety and Stress Scale-21 (DASS-21) is a widely used measurement for psychological symptoms and distress. Some previous studies have shown that the DASS-21 can accurately measure symptoms of anxiety, depression and stress, while other studies have indicated that the DASS-21 mainly measures overall distress. The factor structure of the DASS-21 is important and debated since if affects interpretations of findings. WHAT DOES THIS PAPER ADD TO EXISTING KNOWLEDGE?: In this study, the DASS-21 was translated into Swedish and evaluated in three diverse samples. The DASS-21 subscales of Depression and Anxiety correlated significantly with corresponding criteria instruments. The DASS-21 Stress subscale showed more diverse associations with psychological distress. The analyses supported a bifactor model of the DASS-21 with three specific factors of depression, anxiety and stress as well as a general distress factor. WHAT ARE THE IMPLICATIONS FOR PRACTICE?: The results show that the DASS-21 may be used to measure unique symptoms of depression, anxiety and, with some caveat, stress as well as overall psychological distress. This study confirms that the DASS-21 is theoretically sound instrument that is feasible for both research and clinical practice. The DASS-21 can be an accessible tool for screening and evaluation in first-line mental health services. Introduction There is a constant need for theoretically sound and valid self-report instruments for measuring psychological distress. Previous studies have shown that the Depression, Anxiety and Stress Scale-21 (DASS-21) is theoretically sound, but there have been some inconsistent results regarding its factor structure. Aims The aim of the present study was to investigate and elucidate the factor structure and convergent validity of the DASS-21. Methods A total of 624 participants recruited from student, primary care and psychotherapy populations. The factor structure of the DASS

  17. Internal stress and opto-electronic properties of ZnO thin films deposited by reactive sputtering in various oxygen partial pressures

    Science.gov (United States)

    Tuyaerts, Romain; Poncelet, Olivier; Raskin, Jean-Pierre; Proost, Joris

    2017-10-01

    In this article, we propose ZnO thin films as a suitable material for piezoresistors in transparent and flexible electronics. ZnO thin films have been deposited by DC reactive magnetron sputtering at room temperature at various oxygen partial pressures. All the films have a wurtzite structure with a strong (0002) texture measured by XRD and are almost stoichiometric as measured by inductively coupled plasma optical emission spectroscopy. The effect of oxygen concentration on grain growth has been studied by in-situ multi-beam optical stress sensor, showing internal stress going from 350 MPa to -1.1 GPa. The transition between tensile and compressive stress corresponds to the transition between metallic and oxidized mode of reactive sputtering. This transition also induces a large variation in optical properties—from absorbent to transparent, and in the resistivity—from 4 × 10 - 2 Ω .cm to insulating. Finally, the piezoresistance of the thin film has been studied and showed a gauge factor (ΔR/R)/ɛ comprised between -5.8 and -8.5.

  18. Estrogen receptor β and oxytocin interact to modulate anxiety-like behavior and neuroendocrine stress reactivity in adult male and female rats.

    Science.gov (United States)

    Kudwa, Andrea E; McGivern, Robert F; Handa, Robert J

    2014-04-22

    The hypothalamic-pituitary-adrenal (HPA) axis is activated in response to stressors and is controlled by neurons residing in the paraventricular nucleus of the hypothalamus (PVN). Although gonadal steroid hormones can influence HPA reactivity to stressors, the exact mechanism of action is not fully understood. It is known, however, that estrogen receptor β (ERβ) inhibits HPA reactivity and decreases anxiety-like behavior in rodents. Since ERβ is co-expressed with oxytocin (OT) in neurons of the PVN, an ERβ-selective agonist was utilized to test the whether ERβ decreases stress-induced HPA reactivity and anxiety-like behaviors via an OTergic pathway. Adult gonadectomized male and female rats were administered diarylpropionitrile, or vehicle, peripherally for 5days. When tested for anxiety-like behavior on the elevated plus maze (EPM), diarylpropionitrile-treated males and females significantly increased time on the open arm of the EPM compared to vehicle controls indicating that ERβ reduces anxiety-like behaviors. One week after behavioral evaluation, rats were subjected to a 20minute restraint stress. Treatment with diarylpropionitrile reduced CORT and ACTH responses in both males and females. Subsequently, another group of animals was implanted with cannulae directed at the lateral ventricle. One week later, rats underwent the same protocol as above but with the additional treatment of intracerebroventricular infusion with an OT antagonist (des Gly-NH2 d(CH2)5 [Tyr(Me)(2), Thr(4)] OVT) or VEH, 20min prior to behavioral evaluation. OT antagonist treatment blocked the effects of diarylpropionitrile on the display of anxiety-like behaviors and plasma CORT levels. These data indicate that ERβ and OT interact to modulate the HPA reactivity and the display of anxiety-like behaviors. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Investigation Effect of Shift Work on Job Burnout and Depression, Anxiety, Stress Scale in Military Personnel

    Directory of Open Access Journals (Sweden)

    Ayoub Ghanbary Sartang

    2018-06-01

    Full Text Available Shift work has been recognized as an important tool for organizing of work in developing countries. The disturbed depression, stress accident are the most common health‐related effects of shift work. The military personnel shift worker during work, are exposed to stress and psychological pressure that certainly affect the efficiency of their work. The aim of this study was to Investigation Effect of shift work on job burnout and Depression, Anxiety, Stress Scale in military personnel. This cross-sectional study was carried out on 100 military personnel male in Southern Iran. Respondents were divided into two groups based on their working schedule (50 shift work personnel / 50 day work personnel. Data collection tools were a Depression, Anxiety, and Stress Scale (DASS-21, demographic characteristics and Maslach job burnout questionnaire. Convenience sampling was used as sampling method. Finally, Data analysis was performed with SPSS (version 20, descriptive statistics, One Way Anova test, ANCOVA and t-independent test. The results of showed that shift work has an impact on burnout and DASS-21 and mean obtained score for DASS-21 and job burnout in shift workers are more day work individuals. Analysis of variance test showed significant difference between job burnout in day workers and shift workers and job burnout were more in shift workers. Also significant difference between DASS-21 in day workers and shift workers and DASS-21 was more in shift workers. This study showed that shift work has an impact on burnout and scale DASS-21 shall is taken to Intervention actions in shift works.

  20. There is no news like bad news: women are more remembering and stress reactive after reading real negative news than men.

    Directory of Open Access Journals (Sweden)

    Marie-France Marin

    Full Text Available With the advent of specialized television channels offering 24-hour coverage, Internet and smart phones, the possibility to be constantly in contact with the media has increased dramatically in the last decades. Despite this higher access to knowledge, the impact media exposure has on healthy individuals remains poorly studied. Given that most information conveyed in the media is negative and that upon perception of threat, the brain activates the stress system, which leads to cortisol secretion, we decided to determine how healthy individuals react to media information. Accordingly, we investigated whether reading real negative news (1 is physiologically stressful, (2 modulates one's propensity to be stress reactive to a subsequent stressor and (3 modulates remembrance for these news. Sixty participants (30 women, 30 men were randomly assigned to either twenty-four real neutral news excerpts or to twenty-four real negative excerpts for 10 minutes. They were then all exposed to a well-validated psychosocial stressor, the Trier Social Stress Test (TSST, which consists of an anticipation phase of 10 minutes and a test phase of 10 minutes. A total of eight salivary cortisol samples were collected, at 10-minutes intervals, throughout the experimental procedure. One day later, a free recall of the news was performed. Results showed that although reading negative news did not lead to change in cortisol levels (p>0.05, it led to a significant increase in cortisol to a subsequent stressor in women only (p<0.001. Also, women in the negative news condition experienced better memory for these news excerpts compared to men (p<0.01. These results suggest a potential mechanism by which media exposure could increase stress reactivity and memory for negative news in women.

  1. There is no news like bad news: women are more remembering and stress reactive after reading real negative news than men.

    Science.gov (United States)

    Marin, Marie-France; Morin-Major, Julie-Katia; Schramek, Tania E; Beaupré, Annick; Perna, Andrea; Juster, Robert-Paul; Lupien, Sonia J

    2012-01-01

    With the advent of specialized television channels offering 24-hour coverage, Internet and smart phones, the possibility to be constantly in contact with the media has increased dramatically in the last decades. Despite this higher access to knowledge, the impact media exposure has on healthy individuals remains poorly studied. Given that most information conveyed in the media is negative and that upon perception of threat, the brain activates the stress system, which leads to cortisol secretion, we decided to determine how healthy individuals react to media information. Accordingly, we investigated whether reading real negative news (1) is physiologically stressful, (2) modulates one's propensity to be stress reactive to a subsequent stressor and (3) modulates remembrance for these news. Sixty participants (30 women, 30 men) were randomly assigned to either twenty-four real neutral news excerpts or to twenty-four real negative excerpts for 10 minutes. They were then all exposed to a well-validated psychosocial stressor, the Trier Social Stress Test (TSST), which consists of an anticipation phase of 10 minutes and a test phase of 10 minutes. A total of eight salivary cortisol samples were collected, at 10-minutes intervals, throughout the experimental procedure. One day later, a free recall of the news was performed. Results showed that although reading negative news did not lead to change in cortisol levels (p>0.05), it led to a significant increase in cortisol to a subsequent stressor in women only (pnegative news condition experienced better memory for these news excerpts compared to men (pmedia exposure could increase stress reactivity and memory for negative news in women.

  2. Reactive oxygen species induced by heat stress during grain filling of rice (Oryza sativa L.) are involved in occurrence of grain chalkiness.

    Science.gov (United States)

    Suriyasak, Chetphilin; Harano, Keisuke; Tanamachi, Koichiro; Matsuo, Kazuhiro; Tamada, Aina; Iwaya-Inoue, Mari; Ishibashi, Yushi

    2017-09-01

    Heat stress during grain filling increases rice grain chalkiness due to increased activity of α-amylase, which hydrolyzes starch. In rice and barley seeds, reactive oxygen species (ROS) produced after imbibition induce α-amylase activity via regulation of gibberellin (GA) and abscisic acid (ABA) levels during seed germination. Here, we examined whether ROS is involved in induction of grain chalkiness by α-amylase in developing rice grains under heat stress. To elucidate the role of ROS in grain chalkiness, we grew post-anthesis rice plants (Oryza sativa L. cv. Koshihikari) under control (25°C) or heat stress (30°C) conditions with or without antioxidant (dithiothreitol) treatment. The developing grains were analyzed for expression of NADPH oxidases, GA biosynthesis genes (OsGA3ox1, OsGA20ox1), ABA catabolism genes (OsABA8'OH1, OsABA8'OH2) and an α-amylase gene (OsAmy3E), endogenous H 2 O 2 content and the grain quality. In grains exposed to heat stress, the expression of NADPH oxidase genes (especially, OsRbohB, OsRbohD, OsRbohF and OsRbohI) and the ROS content increased. Heat stress also increased the expression of OsGA3ox1, OsGA20ox1, OsABA8'OH1, OsABA8'OH2 and OsAmy3E. On the other hand, dithiothreitol treatment reduced the effects of heat stress on the expression of these genes and significantly reduced grain chalkiness induced by heat stress. These results suggest that, similar to cereal seed germination mechanism, ROS produced under heat stress is involved in α-amylase induction in maturating rice grains through GA/ABA metabolism, and consequently caused grain chalkiness. Copyright © 2017 Elsevier GmbH. All rights reserved.

  3. Rasch model analysis of the Depression, Anxiety and Stress Scales (DASS).

    Science.gov (United States)

    Shea, Tracey L; Tennant, Alan; Pallant, Julie F

    2009-05-09

    There is a growing awareness of the need for easily administered, psychometrically sound screening tools to identify individuals with elevated levels of psychological distress. Although support has been found for the psychometric properties of the Depression, Anxiety and Stress Scales (DASS) using classical test theory approaches it has not been subjected to Rasch analysis. The aim of this study was to use Rasch analysis to assess the psychometric properties of the DASS-21 scales, using two different administration modes. The DASS-21 was administered to 420 participants with half the sample responding to a web-based version and the other half completing a traditional pencil-and-paper version. Conformity of DASS-21 scales to a Rasch partial credit model was assessed using the RUMM2020 software. To achieve adequate model fit it was necessary to remove one item from each of the DASS-21 subscales. The reduced scales showed adequate internal consistency reliability, unidimensionality and freedom from differential item functioning for sex, age and mode of administration. Analysis of all DASS-21 items combined did not support its use as a measure of general psychological distress. A scale combining the anxiety and stress items showed satisfactory fit to the Rasch model after removal of three items. The results provide support for the measurement properties, internal consistency reliability, and unidimensionality of three slightly modified DASS-21 scales, across two different administration methods. The further use of Rasch analysis on the DASS-21 in larger and broader samples is recommended to confirm the findings of the current study.

  4. Validity of the Depression Anxiety Stress Scales in assessing depression and anxiety following traumatic brain injury.

    Science.gov (United States)

    Dahm, Jane; Wong, Dana; Ponsford, Jennie

    2013-10-01

    Anxiety and depression following traumatic brain injury (TBI) are associated with poorer outcomes. A brief self-report questionnaire would assist in identifying those at risk, however validity of such measures is complicated by confounding symptoms of the injury. This study investigated the validity of the Depression Anxiety Stress Scales (DASS) and Hospital Anxiety and Depression Scale (HADS), in screening for clinical diagnoses of anxiety and mood disorders following TBI. One hundred and twenty-three participants with mild to severe TBI were interviewed using the SCID (Axis I) and completed the DASS and HADS. The DASS, DASS21 and HADS scales demonstrated validity compared with SCID diagnoses of anxiety and mood disorders as measured by Area Under ROC Curve, sensitivity and specificity. Validity of the DASS depression scale benefited from items reflecting symptoms of devaluation of life, self-deprecation, and hopelessness that are not present on the HADS. Validity of the HADS anxiety scale benefited from items reflecting symptoms of tension and worry that are measured separately for the DASS on the stress scale. Participants were predominantly drawn from a rehabilitation centre which may limit the extent to which results can be generalized. Scores for the DASS21 were derived from the DASS rather than being administered separately. The DASS, DASS21 and HADS demonstrated validity as screening measures of anxiety and mood disorders in this TBI sample. The findings support use of these self-report questionnaires for individuals with TBI to identify those who should be referred for clinical diagnostic follow-up. © 2013 Elsevier B.V. All rights reserved.

  5. Rasch model analysis of the Depression, Anxiety and Stress Scales (DASS)

    Science.gov (United States)

    Shea, Tracey L; Tennant, Alan; Pallant, Julie F

    2009-01-01

    Background There is a growing awareness of the need for easily administered, psychometrically sound screening tools to identify individuals with elevated levels of psychological distress. Although support has been found for the psychometric properties of the Depression, Anxiety and Stress Scales (DASS) using classical test theory approaches it has not been subjected to Rasch analysis. The aim of this study was to use Rasch analysis to assess the psychometric properties of the DASS-21 scales, using two different administration modes. Methods The DASS-21 was administered to 420 participants with half the sample responding to a web-based version and the other half completing a traditional pencil-and-paper version. Conformity of DASS-21 scales to a Rasch partial credit model was assessed using the RUMM2020 software. Results To achieve adequate model fit it was necessary to remove one item from each of the DASS-21 subscales. The reduced scales showed adequate internal consistency reliability, unidimensionality and freedom from differential item functioning for sex, age and mode of administration. Analysis of all DASS-21 items combined did not support its use as a measure of general psychological distress. A scale combining the anxiety and stress items showed satisfactory fit to the Rasch model after removal of three items. Conclusion The results provide support for the measurement properties, internal consistency reliability, and unidimensionality of three slightly modified DASS-21 scales, across two different administration methods. The further use of Rasch analysis on the DASS-21 in larger and broader samples is recommended to confirm the findings of the current study. PMID:19426512

  6. Rasch model analysis of the Depression, Anxiety and Stress Scales (DASS

    Directory of Open Access Journals (Sweden)

    Tennant Alan

    2009-05-01

    Full Text Available Abstract Background There is a growing awareness of the need for easily administered, psychometrically sound screening tools to identify individuals with elevated levels of psychological distress. Although support has been found for the psychometric properties of the Depression, Anxiety and Stress Scales (DASS using classical test theory approaches it has not been subjected to Rasch analysis. The aim of this study was to use Rasch analysis to assess the psychometric properties of the DASS-21 scales, using two different administration modes. Methods The DASS-21 was administered to 420 participants with half the sample responding to a web-based version and the other half completing a traditional pencil-and-paper version. Conformity of DASS-21 scales to a Rasch partial credit model was assessed using the RUMM2020 software. Results To achieve adequate model fit it was necessary to remove one item from each of the DASS-21 subscales. The reduced scales showed adequate internal consistency reliability, unidimensionality and freedom from differential item functioning for sex, age and mode of administration. Analysis of all DASS-21 items combined did not support its use as a measure of general psychological distress. A scale combining the anxiety and stress items showed satisfactory fit to the Rasch model after removal of three items. Conclusion The results provide support for the measurement properties, internal consistency reliability, and unidimensionality of three slightly modified DASS-21 scales, across two different administration methods. The further use of Rasch analysis on the DASS-21 in larger and broader samples is recommended to confirm the findings of the current study.

  7. Characterizing the Potential for Injection-Induced Fault Reactivation Through Subsurface Structural Mapping and Stress Field Analysis, Wellington Field, Sumner County, Kansas

    Science.gov (United States)

    Schwab, Drew R.; Bidgoli, Tandis S.; Taylor, Michael H.

    2017-12-01

    Kansas, like other parts of the central U.S., has experienced a recent increase in seismicity. Correlation of these events with brine disposal operations suggests pore fluid pressure increases are reactivating preexisting faults, but rigorous evaluation at injection sites is lacking. Here we determine the suitability of CO2 injection into the Cambrian-Ordovician Arbuckle Group for long-term storage and into a Mississippian reservoir for enhanced oil recovery in Wellington Field, Sumner County, Kansas. To determine the potential for injection-induced earthquakes, we map subsurface faults and estimate in situ stresses, perform slip and dilation tendency analyses to identify well-oriented faults relative to the estimated stress field, and determine the pressure changes required to induce slip at reservoir and basement depths. Three-dimensional seismic reflection data reveal 12 near-vertical faults, mostly striking NNE, consistent with nodal planes from moment tensor solutions from recent earthquakes in the region. Most of the faults cut both reservoirs and several clearly penetrate the Precambrian basement. Drilling-induced fractures (N = 40) identified from image logs and inversion of earthquake moment tensor solutions (N = 65) indicate that the maximum horizontal stress is approximately EW. Slip tendency analysis indicates that faults striking <020° are stable under current reservoir conditions, whereas faults striking 020°-049° may be prone to reactivation with increasing pore fluid pressure. Although the proposed injection volume (40,000 t) is unlikely to reactive faults at reservoir depths, high-rate injection operations could reach pressures beyond the critical threshold for slip within the basement, as demonstrated by the large number of injection-induced earthquakes west of the study area.

  8. Site of mitochondrial reactive oxygen species production in skeletal muscle of chronic obstructive pulmonary disease and its relationship with exercise oxidative stress.

    Science.gov (United States)

    Puente-Maestu, Luis; Tejedor, Alberto; Lázaro, Alberto; de Miguel, Javier; Alvarez-Sala, Luis; González-Aragoneses, Federico; Simón, Carlos; Agustí, Alvar

    2012-09-01

    Exercise triggers skeletal muscle oxidative stress in patients with chronic obstructive pulmonary disease (COPD). The objective of this research was to study the specific sites of reactive oxygen species (ROS) production in mitochondria isolated from skeletal muscle of patients with COPD and its relationship with local oxidative stress induced by exercise. Vastus lateralis biopsies were obtained in 16 patients with COPD (66 ± 10 yr; FEV(1), 54 ± 12% ref) and in 14 control subjects with normal lung function who required surgery because of lung cancer (65 ± 7 yr; FEV(1), 91 ± 14% ref) at rest and after exercise. In these biopsies we isolated mitochondria and mitochondrial membrane fragments and determined in vitro mitochondrial oxygen consumption (Mit$$\\stackrel{.}{\\hbox{ V }}$$o(2)) and ROS production before and after inhibition of complex I (rotenone), complex II (stigmatellin), and complex III (antimycin-A). We related the in vitro ROS production during state 3 respiration), which mostly corresponds to the mitochondria respiratory state during exercise, with skeletal muscle oxidative stress after exercise, as measured by thiobarbituric acid reactive substances.State 3 Mit$$\\stackrel{.}{\\hbox{ V }}$$o(2) was similar in patients with COPD and control subjects (191 ± 27 versus 229 ± 46 nmol/min/mg; P = 0.058), whereas H(2)O(2) production was higher in the former (147 ± 39 versus 51 ± 8 pmol/mg/h; P release by mitochondria in patients with COPD and in control subjects. The mitochondrial production of H(2)O(2) in state 3 respiration was related (r = 0.69; P < 0.001) to postexercise muscle thiobarbituric acid reactive substance levels. Our results show that complex III is the main site of the enhanced mitochondrial H(2)O(2) production that occurs in skeletal muscle of patients with COPD, and the latter appears to contribute to muscle oxidative damage.

  9. Stress reactivity and its effects on subsequent food intake in depressed and healthy women with and without adverse childhood experiences.

    Science.gov (United States)

    Wingenfeld, Katja; Kuehl, Linn K; Boeker, Anita; Schultebraucks, Katharina; Ritter, Kristin; Hellmann-Regen, Julian; Otte, Christian; Spitzer, Carsten

    2017-06-01

    Adverse childhood experiences (ACE) increase the risk to develop major depressive disorder (MDD) and obesity or metabolic syndrome in adulthood. In addition, ACE may be associated with an exaggerated endocrine response to stress, which, in turn, may lead to enhanced food intake resulting in obesity and metabolic problems. We systematically examined the stress response and consecutive food intake in 32 women with MDD and ACE as determined by a clinical interview (Early Trauma Inventory), 52 women with MDD without ACE, 22 women with ACE but no current or lifetime MDD and 37 healthy women without either MDD or ACE. All participants underwent a psychosocial stress test (Trier Social Stress Test, TSST) and a control condition (Placebo-TSST) before they were offered a buffet of snacks. Participants were not aware that the primary outcome variable was the amount of consumed kilocalories (kcal). The four groups did not differ in demographic variables. Stress resulted in higher cortisol release and higher blood pressure compared to the control condition. Patients with MDD without ACE had a significantly lower cortisol response to stress compared to controls. Across groups, we found higher kcal intake after stress compared to the control condition. Comparing high and low cortisol responders to stress, higher kcal intake after stress was only seen in those with low cortisol release. This study provides evidence that blunted rather than enhanced cortisol release to stress might lead to increased food intake, independent from MDD and ACE. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Curcumin enhances the effects of irinotecan on colorectal cancer cells through the generation of reactive oxygen species and activation of the endoplasmic reticulum stress pathway.

    Science.gov (United States)

    Huang, Yan-Feng; Zhu, Da-Jian; Chen, Xiao-Wu; Chen, Qi-Kang; Luo, Zhen-Tao; Liu, Chang-Chun; Wang, Guo-Xin; Zhang, Wei-Jie; Liao, Nv-Zhu

    2017-06-20

    Although initially effective against metastatic colorectal cancer (CRC), irinotecan-based chemotherapy leads to resistance and adverse toxicity. Curcumin is well known for its anti-cancer effects in many cancers, including CRC. Here, we describe reactive oxygen species (ROS) generation and endoplasmic reticulum (ER) stress as important mechanisms by which curcumin enhances irinotecan's effects on CRC cells. CRC cell lines were treated with curcumin and/or irinotecan for 24 h, and then evaluated using cell proliferation assays, cell apoptosis assays, cell cycle analysis, intracellular Ca2+ measurements, ROS measurements and immunoblotting for key ER stress-related proteins. We found that cell viability was inhibited and apoptosis was increased, accompanied by ROS generation and ER stress activation in CRC cells treated with curcumin alone or in combination with irinotecan. Blocking ROS production attenuated the expression of two markers of ER stress: binding of immunoglobulin protein (BIP) and CCAAT/enhancer-binding protein homologous protein (CHOP). Blocking CHOP expression using RNA interference also inhibited ROS generation. These results demonstrated that curcumin could enhance the effects of irinotecan on CRC cells by inhibiting cell viability and inducing cell cycle arrest and apoptosis, and that these effects may be mediated, in part, by ROS generation and activation of the ER stress pathway.

  11. Using the Depression Anxiety Stress Scale 21 (DASS-21) across cultures.

    Science.gov (United States)

    Oei, Tian P S; Sawang, Sukanlaya; Goh, Yong Wah; Mukhtar, Firdaus

    2013-01-01

    The DASS-21 is a well-established instrument for measuring depression, anxiety, and stress with good reliability and validity reported from Hispanic American, British, and Australian adults. However, the lack of appropriate validation among Asian populations continues to pose concerns over the use of DASS-21 in Asian samples. Cultural variation may influence the individual's experience and emotional expression. Thus, when researchers and practitioners employ Western-based assessments with Asian populations by directly translating them without an appropriate validation, the process can be challenging. We conducted a series of rigorous statistical tests and minimized any potential confounds from the demographic information. Following factor analyses, we performed multigroup analysis across six nations to demonstrate consistency of our findings. The advantages of this revised DASS-18 stress scale are twofold. First, it possesses fewer items, which results in a cleaner factorial structure. Second, it has a smaller interfactor correlation. With these justifications, the revised DASS-18 stress scale is potentially more suitable for Asian populations. Nonetheless, given limitations, findings should be considered preliminary.

  12. Clinical validity of a relocation stress scale for the families of patients transferred from intensive care units.

    Science.gov (United States)

    Oh, HyunSoo; Lee, Seul; Kim, JiSun; Lee, EunJu; Min, HyoNam; Cho, OkJa; Seo, WhaSook

    2015-07-01

    This study was conducted to develop a family relocation stress scale by modifying the Son's Relocation Stress Syndrome Scale, to examine its clinical validity and reliability and to confirm its suitability for measuring family relocation stress. The transfer of ICU patients to general wards is a significant anxiety-producing event for family members. However, no relocation stress scale has been developed specifically for families. A nonexperimental, correlation design was adopted. The study subjects were 95 family members of 95 ICU patients at a university hospital located in Incheon, South Korea. Face and construct validities of the devised family relocation stress scale were examined. Construct validity was examined using factor analysis and by using a nomological validity test. Reliability was also examined. Face and content validity of the scale were verified by confirming that its items adequately measured family relocation stress. Factor analysis yielded four components, and the total variance explained by these four components was 63·0%, which is acceptable. Nomological validity was well supported by significant relationships between relocation stress and degree of preparation for relocation, patient self-care ability, family burden and satisfaction with the relocation process. The devised scale was also found to have good reliability. The family relocation stress scale devised in this study was found to have good validity and reliability, and thus, is believed to offer a means of assessing family relocation stress. The findings of this study provide a reliable and valid assessment tool when nurses prepare families for patient transfer from an ICU to a ward setting, and may also provide useful information to those developing an intervention programme for family relocation stress management. © 2015 John Wiley & Sons Ltd.

  13. Size scale dependence of compressive instabilities in layered composites in the presence of stress gradients

    DEFF Research Database (Denmark)

    Poulios, Konstantinos; Niordson, Christian Frithiof

    2016-01-01

    The compressive strength of unidirectionally or layer-wise reinforced composite materials in direction parallel to their reinforcement is limited by micro-buckling instabilities. Although the inherent compressive strength of a given material micro-structure can easily be determined by assessing its...... compressive stress but also on spatial stress or strain gradients, rendering failure initiation size scale dependent. The present work demonstrates and investigates the aforementioned effect through numerical simulations of periodically layered structures withnotches and holes under bending and compressive...... loads, respectively. The presented results emphasize the importance of the reinforcing layer thickness on the load carrying capacity of the investigated structures, at a constant volumetric fraction of the reinforcement. The observed strengthening at higher values of the relative layer thickness...

  14. The Femininity Ideology Scale (FIS): dimensions and its relationship to anxiety and feminine gender role stress.

    Science.gov (United States)

    Richmond, Katherine; Levant, Ronald; Smalley, Bryant; Cook, Stephen

    2015-01-01

    The purpose of this study was to conduct a confirmatory factor analytic investigation of the Femininity Ideology Scale (FIS) and to assess whether feminine gender role stress mediated the relationship between femininity ideology and anxiety. During the 2010-2011 academic year, a convenience sample of 606 college women were recruited from three universities and one college. Confirmatory factor analysis supported a four- versus the hypothesized five-factor model, resulting in the elimination of the Dependency/Deference factor. Mediation analysis using structural equation modeling indicated no direct relationship between Femininity Ideology and Anxiety, although an indirect one was observed, mediated through Feminine Gender Role Stress. The results are discussed in terms of possible changes in contemporary notions of femininity, and the utility of using the FIS in applied