WorldWideScience

Sample records for stress specific subjects

  1. Feeding rates affect stress and non-specific immune responses of juvenile blunt snout bream Megalobrama amblycephala subjected to hypoxia.

    Science.gov (United States)

    Li, Xiang-Fei; Xu, Chao; Tian, Hong-Yan; Jiang, Guang-Zhen; Zhang, Ding-Dong; Liu, Wen-Bin

    2016-02-01

    This study aimed to investigate the effects of feeding rates on stress response, innate immunity and hypoxia resistance of juvenile blunt snout bream Megalobrama amblycephala. Fish were randomly assigned to one of six feeding rates (2, 3, 4, 5, 6 and 7% of body weight/day) for 60 days. Then, fish were subjected to hypoxic conditions and haemato-immunological parameters were analyzed pre- and post-challenge. Low feed ration resulted in decreased liver superoxide dismutase and catalase activities and reduced glutathione contents. Inadequate feeding also adversely affected the immune functions of fish, as was characterized by the relatively low haemato-immunological parameters (including alternative complement (ACH50), myeloperoxidase (MPO), plasma protein profiles and transferring) and high hypoxia-induced mortality. High feed ration did not lead to the improvement in antioxidant capability, immune responses and survival. In addition, plasma cortisol, glucose and transferrin levels as well as lysozyme activities all increased significantly after hypoxia challenge, whereas the opposite was true for plasma ACH50 and MPO activities as well as protein profiles in terms of hypoxia challenge. An interaction between feeding rate and hypoxia was also observed in plasma cortisol, glucose and protein profiles. In conclusion, a feeding rate of 4-5% of body weight/day is optimal to boost the innate immunity of juvenile blunt snout bream. Low ration resulted in decreased antioxidant capability, compromised immune functions and reduced hypoxia resistance, while over feeding did not benefit the health status. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Real-time subject-specific monitoring of internal deformations and stresses in the soft tissues of the foot: a new approach in gait analysis.

    Science.gov (United States)

    Yarnitzky, G; Yizhar, Z; Gefen, A

    2006-01-01

    No technology is presently available to provide real-time information on internal deformations and stresses in plantar soft tissues of individuals during evaluation of the gait pattern. Because internal deformations and stresses in the plantar pad are critical factors in foot injuries such as diabetic foot ulceration, this severely limits evaluation of patients. To allow such real-time subject-specific analysis, we developed a hierarchal modeling system which integrates a two-dimensional gross structural model of the foot (high-order model) with local finite element (FE) models of the plantar tissue padding the calcaneus and medial metatarsal heads (low-order models). The high-order whole-foot model provides real-time analytical evaluations of the time-dependent plantar fascia tensile forces during the stance phase. These force evaluations are transferred, together with foot-shoe local reaction forces, also measured in real time (under the calcaneus, medial metatarsals and hallux), to the low-order FE models of the plantar pad, where they serve as boundary conditions for analyses of local deformations and stresses in the plantar pad. After careful verification of our custom-made FE solver and of our foot model system with respect to previous literature and against experimental results from a synthetic foot phantom, we conducted human studies in which plantar tissue loading was evaluated in real time during treadmill gait in healthy individuals (N = 4). We concluded that internal deformations and stresses in the plantar pad during gait cannot be predicted from merely measuring the foot-shoe force reactions. Internal loading of the plantar pad is constituted by a complex interaction between the anatomical structure and mechanical behavior of the foot skeleton and soft tissues, the body characteristics, the gait pattern and footwear. Real-time FE monitoring of internal deformations and stresses in the plantar pad is therefore required to identify elevated deformation/stress

  3. Subjective time pressure: general or domain specific?

    Science.gov (United States)

    Kleiner, Sibyl

    2014-09-01

    Chronic time pressure has been identified as a pervasive societal problem, exacerbated by high demands of the labor market and the home. Yet time pressure has not been disaggregated and examined separately across home and work contexts, leaving many unanswered questions regarding the sources and potentially stressful consequences of time pressure. Using data collected in the United States General Social Survey waves 2002 and 2004, this study disaggregates time pressure into the domains of home and work, and asks whether considering time pressures within distinct work and home contexts reveals distinct predictors or associations with stress. Findings show that both predictors and stress associations differ across work and home pressures, revealing both methodological and theoretical implications for the study of time pressure and work and family life more generally. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. When does stress help or harm? The effects of stress controllability and subjective stress response on stroop performance.

    Science.gov (United States)

    Henderson, Roselinde K; Snyder, Hannah R; Gupta, Tina; Banich, Marie T

    2012-01-01

    The ability to engage in goal-directed behavior despite exposure to stress is critical to resilience. Questions of how stress can impair or improve behavioral functioning are important in diverse settings, from athletic competitions to academic testing. Previous research suggests that controllability is a key factor in the impact of stress on behavior: learning how to control stressors buffers people from the negative effects of stress on subsequent cognitively demanding tasks. In addition, research suggests that the impact of stress on cognitive functioning depends on an individual's response to stressors: moderate responses to stress can lead to improved performance while extreme (high or low) responses can lead to impaired performance. The present studies tested the hypothesis that (1) learning to behaviorally control stressors leads to improved performance on a test of general executive functioning, the color-word Stroop, and that (2) this improvement emerges specifically for people who report moderate (subjective) responses to stress. Experiment 1: Stroop performance, measured before and after a stress manipulation, was compared across groups of undergraduate participants (n = 109). People who learned to control a noise stressor and received accurate performance feedback demonstrated reduced Stroop interference compared with people exposed to uncontrollable noise stress and feedback indicating an exaggerated rate of failure. In the group who learned behavioral control, those who reported moderate levels of stress showed the greatest reduction in Stroop interference. In contrast, in the group exposed to uncontrollable events, self-reported stress failed to predict performance. Experiment 2: In a second sample (n = 90), we specifically investigated the role of controllability by keeping the rate of failure feedback constant across groups. In the group who learned behavioral control, those who reported moderate levels of stress showed the greatest Stroop

  5. When does stress help or harm? The effects of stress controllability and subjective stress response on Stroop performance.

    Directory of Open Access Journals (Sweden)

    Roselinde Kaiser Henderson

    2012-06-01

    Full Text Available The ability to engage in goal-directed behavior despite exposure to stress is critical to resilience. Questions of how stress can impair or improve behavioral functioning are important in diverse settings, from athletic competitions to academic testing to clinical therapy. Previous research suggests that controllability is a key factor in the impact of stress on behavior: learning how to control stressors buffers people from the negative effects of stress on subsequent cognitively demanding tasks. In addition, research suggests that the impact of stress on cognitive functioning depends on an individual’s response to stressors: moderate responses to stress can lead to improved performance while extreme (high or low responses can lead to impaired performance. The present studies tested the hypothesis that 1 learning to behaviorally control stressors leads to improved performance on a test of general executive functioning, the color-word Stroop, and that 2 this improvement emerges specifically for people who report moderate (subjective responses to stress. Experiment 1: Stroop performance, measured before and after a stress manipulation, was compared across groups of undergraduate participants (n=109. People who learned to control a noise stressor and received accurate performance feedback demonstrated reduced Stroop interference compared with people exposed to uncontrollable noise stress and feedback indicating an exaggerated rate of failure. In the group who learned behavioral control, those who reported moderate levels of stress showed the greatest reduction in Stroop interference. In contrast, in the group exposed to uncontrollable events, self-reported stress failed to predict performance. Experiment 2: In a second sample (n=90, we specifically investigated the role of controllability by keeping the rate of failure feedback constant across groups. In the group who learned behavioral control, those who reported moderate levels of stress

  6. Differentiation chronic post traumatic stress disorder patients from healthy subjects using objective and subjective sleep-related parameters.

    Science.gov (United States)

    Tahmasian, Masoud; Jamalabadi, Hamidreza; Abedini, Mina; Ghadami, Mohammad R; Sepehry, Amir A; Knight, David C; Khazaie, Habibolah

    2017-05-22

    Sleep disturbance is common in chronic post-traumatic stress disorder (PTSD). However, prior work has demonstrated that there are inconsistencies between subjective and objective assessments of sleep disturbance in PTSD. Therefore, we investigated whether subjective or objective sleep assessment has greater clinical utility to differentiate PTSD patients from healthy subjects. Further, we evaluated whether the combination of subjective and objective methods improves the accuracy of classification into patient versus healthy groups, which has important diagnostic implications. We recruited 32 chronic war-induced PTSD patients and 32 age- and gender-matched healthy subjects to participate in this study. Subjective (i.e. from three self-reported sleep questionnaires) and objective sleep-related data (i.e. from actigraphy scores) were collected from each participant. Subjective, objective, and combined (subjective and objective) sleep data were then analyzed using support vector machine classification. The classification accuracy, sensitivity, and specificity for subjective variables were 89.2%, 89.3%, and 89%, respectively. The classification accuracy, sensitivity, and specificity for objective variables were 65%, 62.3%, and 67.8%, respectively. The classification accuracy, sensitivity, and specificity for the aggregate variables (combination of subjective and objective variables) were 91.6%, 93.0%, and 90.3%, respectively. Our findings indicate that classification accuracy using subjective measurements is superior to objective measurements and the combination of both assessments appears to improve the classification accuracy for differentiating PTSD patients from healthy individuals. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Are Autonomous and Controlled Motivations School-Subjects-Specific?

    Science.gov (United States)

    Chanal, Julien; Guay, Frédéric

    2015-01-01

    This research sought to test whether autonomous and controlled motivations are specific to school subjects or more general to the school context. In two cross-sectional studies, 252 elementary school children (43.7% male; mean age = 10.7 years, SD = 1.3 years) and 334 junior high school children (49.7% male, mean age = 14.07 years, SD = 1.01 years) were administered a questionnaire assessing their motivation for various school subjects. Results based on structural equation modeling using the correlated trait-correlated method minus one model (CTCM-1) showed that autonomous and controlled motivations assessed at the school subject level are not equally school-subject-specific. We found larger specificity effects for autonomous (intrinsic and identified) than for controlled (introjected and external) motivation. In both studies, results of factor loadings and the correlations with self-concept and achievement demonstrated that more evidence of specificity was obtained for autonomous regulations than for controlled ones. These findings suggest a new understanding of the hierarchical and multidimensional academic structure of autonomous and controlled motivations and of the mechanisms involved in the development of types of regulations for school subjects. PMID:26247788

  8. Subjective stress factors in centrifuge training for military aircrews.

    Science.gov (United States)

    Lin, Pei-Chun; Wang, Jenhung; Li, Shih-Chin

    2012-07-01

    This study investigates stress-influence factors perceived by military aircrews undergoing centrifuge training, which lowers the incidence of G-induced loss of consciousness (G-LOC) for the crews of high-performance combat aircrafts. We used questionnaires to assess the subjective stress-influence factors of crews undergoing centrifuge training. Professionals in aviation physiology identified attributes measuring the perceived stress induced by centrifuge training, which were segmented into three constructs by factor analysis, theory lecture, centrifuge equipment, and physical fitness. Considerable interpenetration was discernible between these factors and military rank, age, length of service, flight hours accrued, and type of aircraft piloted. Identifying and quantifying the perceived stressors experienced in human-use centrifuge training enables aviators, astronauts, and air forces of the world to determine which constructs perceptibly increase or alleviate the perceived stress undergone by trainees when partaking in centrifuge training. Copyright © 2011 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  9. PERSONALITY AS SUBJECT OF THE RELATION TO THE STRESS

    Directory of Open Access Journals (Sweden)

    Milena Aleksandrovna Klenova

    2015-08-01

    Full Text Available In this scientific article results of the empirical research devoted to studying of the personality as the subject of the relation to a stress are presented. The understanding of a phenomenon of a stress not only taking into account social and psychological features of the personality, but also with inclusion of such category as representations of a stress and the relation towards him for the first time is considered by authors. In empirical research it is established that there are five types of the personality, as subjects of the relation to a stress according to their social and psychological features and ideas of a stress. «Destructive persons» – differ in the reduced level of social and psychological adaptation, they are motivated on failure, and the stress is perceived by them as emotional excitement. «Constructive persons» possess the high level of social and psychological adaptation, are focused on success, for them emotional burning out isn’t characteristic, and their representations and the relation to a stress is based on acceptance of existence of eustressor. «Emotional and intense persons» differ in uneasiness, high level of emotional burning out, and their ideas of a stress are based only on negative characteristics. «Sensitive persons» are characterized by the high level of sensitivity, and their relation to a stress can be defined as «mental anguish». For «rational persons» cognitive approach to a situation of a stress and idea of it as about response of an organism to negative emotions is peculiar. Thus, this scientific article represents results of original research of the personality from a position of its relation to a stress.Purpose: to study social and psychological features of the personality with inclusion of such category as «representations and the relation to a stress».Method or methodology of research it is based on the concept of social representations of S.Moskovichi, and also on the subject

  10. Introspection of subjective feelings is sensitive and specific.

    Science.gov (United States)

    Questienne, Laurence; van Dijck, Jean-Philippe; Gevers, Wim

    2018-02-01

    Conversely to behaviorist ideas, recent studies suggest that introspection can be accurate and reliable. However, an unresolved question is whether people are able to report specific aspects of their phenomenal experience, or whether they report more general nonspecific experiences. To address this question, we investigated the sensitivity and validity of our introspection for different types of conflict. Taking advantage of the congruency sequence effect, we dissociated response conflict while keeping visual conflict unchanged in a Stroop and in a priming task. Participants were subsequently asked to report on either their experience of urge to err or on their feeling of visual conflict. Depending on the focus of the introspection, subjective reports specifically followed either the response conflict or the visual conflict. These results demonstrate that our introspective reports can be sensitive and that we are able to dissociate specific aspects of our phenomenal experiences in a valid manner. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  11. Age, subjective stress, and depression after ischemic stroke.

    Science.gov (United States)

    McCarthy, Michael J; Sucharew, Heidi J; Alwell, Kathleen; Moomaw, Charles J; Woo, Daniel; Flaherty, Matthew L; Khatri, Pooja; Ferioli, Simona; Adeoye, Opeolu; Kleindorfer, Dawn O; Kissela, Brett M

    2016-02-01

    The incidence of stroke among younger adults in the United States is increasing. Few studies have investigated the prevalence of depressive symptoms after stroke among different age groups or the extent to which subjective stress at the time of stroke interacts with age to contribute to post-stroke depression. The present study examined whether there exists an age gradient in survivors' level of depressive symptoms and explored the extent to which financial, family, and health-related stress may also impact on depression. Bivariate analyses (N = 322) indicated significant differences in depression and stress by age group, as well as differences in age and stress by 3-month depression status. Linear regression analyses indicated that survivors between the ages of 25-54 and 55-64 years old had, on average, significantly higher depressive symptom scores. Those with financial, family, and health-related stress at the time of stroke, irrespective of age, also had significantly higher scores.

  12. Method for measuring biaxial stress in a body subjected to stress inducing loads

    Science.gov (United States)

    Clotfelter, W. N. (Inventor)

    1977-01-01

    A method is described for measuring stress in test articles including the steps of obtaining for a calibrating specimen a series of transit time differentials between the second wave echo for a longitudinal wave and the first wave echo for each of a pair of shear waves propagated through the specimen as it is subjected to known stress load of a series of stress loads for thus establishing a series of indications of the magnitudes for stress loads induced in the specimen, and thereafter obtaining a transit time differential between the second wave echo for a longitudinal wave and the first wave echo for each of a pair of shear waves propagated in the planes of the stress axes of a test article and comparing the transit time differential thus obtained to the series of transit time differentials obtained for the specimen to determine the magnitude of biaxial stress in the test article.

  13. Modelling of subject specific based segmental dynamics of knee joint

    Science.gov (United States)

    Nasir, N. H. M.; Ibrahim, B. S. K. K.; Huq, M. S.; Ahmad, M. K. I.

    2017-09-01

    This study determines segmental dynamics parameters based on subject specific method. Five hemiplegic patients participated in the study, two men and three women. Their ages ranged from 50 to 60 years, weights from 60 to 70 kg and heights from 145 to 170 cm. Sample group included patients with different side of stroke. The parameters of the segmental dynamics resembling the knee joint functions measured via measurement of Winter and its model generated via the employment Kane's equation of motion. Inertial parameters in the form of the anthropometry can be identified and measured by employing Standard Human Dimension on the subjects who are in hemiplegia condition. The inertial parameters are the location of centre of mass (COM) at the length of the limb segment, inertia moment around the COM and masses of shank and foot to generate accurate motion equations. This investigation has also managed to dig out a few advantages of employing the table of anthropometry in movement biomechanics of Winter's and Kane's equation of motion. A general procedure is presented to yield accurate measurement of estimation for the inertial parameters for the joint of the knee of certain subjects with stroke history.

  14. Stiffness Evolution in Frozen Sands Subjected to Stress Changes

    KAUST Repository

    Dai, Sheng; Santamarina, Carlos

    2017-01-01

    Sampling affects all soils, including frozen soils and hydrate-bearing sediments. The authors monitor the stiffness evolution of frozen sands subjected to various temperature and stress conditions using an oedometer cell instrumented with P-wave transducers. Experimental results show the stress-dependent stiffness of freshly remolded sands, the dominant stiffening effect of ice, creep after unloading, and the associated exponential decrease in stiffness with time. The characteristic time for stiffness loss during creep is of the order of tens of minutes; therefore it is inevitable that frozen soils experience sampling disturbances attributable to unloading. Slow unloading minimizes stiffness loss; conversely, fast unloading causes a pronounced reduction in stiffness probably attributable to the brittle failure of ice or ice-mineral bonding.

  15. Stiffness Evolution in Frozen Sands Subjected to Stress Changes

    KAUST Repository

    Dai, Sheng

    2017-04-21

    Sampling affects all soils, including frozen soils and hydrate-bearing sediments. The authors monitor the stiffness evolution of frozen sands subjected to various temperature and stress conditions using an oedometer cell instrumented with P-wave transducers. Experimental results show the stress-dependent stiffness of freshly remolded sands, the dominant stiffening effect of ice, creep after unloading, and the associated exponential decrease in stiffness with time. The characteristic time for stiffness loss during creep is of the order of tens of minutes; therefore it is inevitable that frozen soils experience sampling disturbances attributable to unloading. Slow unloading minimizes stiffness loss; conversely, fast unloading causes a pronounced reduction in stiffness probably attributable to the brittle failure of ice or ice-mineral bonding.

  16. Stress and Subjective Age: Those With Greater Financial Stress Look Older.

    Science.gov (United States)

    Agrigoroaei, Stefan; Lee-Attardo, Angela; Lachman, Margie E

    2017-12-01

    Subjective indicators of age add to our understanding of the aging process beyond the role of chronological age. We examined whether financial stress contributes to subjective age as rated by others and the self. The participants ( N = 228), aged 26-75, were from a Boston area satellite of the Midlife in the United States (MIDUS) longitudinal study. Participants reported how old they felt and how old they thought they looked, and observers assessed the participants' age based on photographs (other-look age), at two occasions, an average of 10 years apart. Financial stress was measured at Time 1. Controlling for income, general stress, health, and attractiveness, participants who reported higher levels of financial stress were perceived as older than their actual age to a greater extent and showed larger increases in other-look age over time. We consider the results on accelerated aging of appearance with regard to their implications for interpersonal interactions and in relation to health.

  17. Socioeconomic Status, Subjective Social Status, and Perceived Stress: Associations with Stress Physiology and Executive Functioning.

    Science.gov (United States)

    Ursache, Alexandra; Noble, Kimberly G; Blair, Clancy

    2015-01-01

    Several studies have investigated associations between socioeconomic status (SES) and indicators of children's physiological and cognitive self-regulation. Although objective measures of family SES may be good proxies for families' experiences of disadvantage, less is known about subjective aspects of families' experiences. We hypothesize that subjective social status (SSS) and perceived stress may be important independent predictors of children's stress physiology and executive functioning (EF). Eighty-two children from diverse SES backgrounds were administered EF measures and provided saliva samples for cortisol assay. Caregivers reported on objective SES, SSS, and perceived stress. Results suggest that SES and SSS are both independently and positively related to EF. In models predicting stress physiology, higher perceived stress was associated with lower baseline cortisol. Moreover, SES and age interacted to predict cortisol levels such that among younger children, lower SES was associated with higher cortisol, whereas among older children, lower SES was associated with lower cortisol. Results highlight the importance of considering both objective and subjective indicators of families' SES and stressful experiences in relation to multiple aspects of children's self-regulation.

  18. Sex differences in cardiovascular and subjective stress reactions: prospective evidence in a realistic military setting.

    Science.gov (United States)

    Taylor, Marcus K; Larson, Gerald E; Hiller Lauby, Melissa D; Padilla, Genieleah A; Wilson, Ingrid E; Schmied, Emily A; Highfill-McRoy, Robyn M; Morgan, Charles A

    2014-01-01

    Evidence points to heightened physiological arousal in response to acute stress exposure as both a prospective indicator and a core characteristic of posttraumatic stress disorder (PTSD). Because females may be at higher risk for PTSD development, it is important to evaluate sex differences in acute stress reactions. This study characterized sex differences in cardiovascular and subjective stress reactions among military survival trainees. One hundred and eighty-five military members (78% males) were studied before, during, and 24 h after stressful mock captivity. Cardiovascular (heart rate [HR], systolic blood pressure [SBP], diastolic blood pressure [DBP]) and dissociative states were measured at all three time points. Psychological impact of mock captivity was assessed during recovery. General linear modeling with repeated measures evaluated sex differences for each cardiovascular endpoint, and causal steps modeling was used to explore interrelationships among sex, cardiovascular reactions and psychological impact of mock captivity. Although females had lower SBP than males at all three time points, the difference was most pronounced at baseline and during stress. Accordingly, females showed greater residual elevation in SBP during recovery. Females had lower DBP at all three time points. In addition, females reported greater psychological impact of mock captivity than males. Exploratory causal steps modeling suggested that stress-induced HR may partially mediate the effect of sex on psychological impact of mock captivity. In conclusion, this study demonstrated sex-specific cardiovascular stress reactions in military personnel, along with greater psychological impact of stress exposure in females. This research may elucidate sex differences in PTSD development.

  19. Oxidative stress and inflammation in renal patients and healthy subjects.

    Directory of Open Access Journals (Sweden)

    Diana M Lee

    Full Text Available The first goal of this study was to measure the oxidative stress (OS and relate it to lipoprotein variables in 35 renal patients before dialysis (CKD, 37 on hemodialysis (HD and 63 healthy subjects. The method for OS was based on the ratio of cholesteryl esters (CE containing C18/C16 fatty acids (R2 measured by gas chromatography (GC which is a simple, direct, rapid and reliable procedure. The second goal was to investigate and identify a triacylglycerol peak on GC, referred to as TG48 (48 represents the sum of the three fatty acids carbon chain lengths which was markedly increased in renal patients compared to healthy controls. We measured TG48 in patients and controls. Mass spectrometry (MS and MS twice in tandem were used to analyze the fatty acid composition of TG48. MS showed that TG48 was abundant in saturated fatty acids (SFAs that were known for their pro-inflammatory property. TG48 was significantly and inversely correlated with OS. Renal patients were characterized by higher OS and inflammation than healthy subjects. Inflammation correlated strongly with TG, VLDL-cholesterol, apolipoprotein (apo C-III and apoC-III bound to apoB-containing lipoproteins, but not with either total cholesterol or LDL-cholesterol.In conclusion, we have discovered a new inflammatory factor, TG48. It is characterized with TG rich in saturated fatty acids. Renal patients have increased TG48 than healthy controls.

  20. Oxidative stress in hepatitis C infected end-stage renal disease subjects

    OpenAIRE

    Koylu Ahmet O; Aslan Mehmet; Bolukbas Filiz F; Bolukbas Cengiz; Horoz Mehmet; Selek Sahbettin; Erel Ozcan

    2006-01-01

    Abstract Background Both uremia and hepatitis C infection is associated with increased oxidative stress. In the present study, we aimed to find out whether hepatitis C infection has any impact on oxidative stress in hemodialysis subjects. Methods Sixteen hepatitis C (+) hemodialysis subjects, 24 hepatitis C negative hemodialysis subjects and 24 healthy subjects were included. Total antioxidant capacity, total peroxide level and oxidative stress index were determined in all subjects. Results T...

  1. 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.

  2. Specific strain work as a failure criterion in plane stress state

    International Nuclear Information System (INIS)

    Zuchowski, R.; Zietkowski, L.

    1985-01-01

    An experimental verification of failure criterion based on specific strain work was performed. Thin-walled cylindrical specimens were examined by loading with constant force and constant torque moment, assuming different values for particular tests, at the same time keeping stress intensity constant, and by subjecting to thermal cycling. It was found that the critical value of failure did not depend on axial-to-shearing stresses ratio, i.e., on the type of state of stress. Thereby, the validity of the analysed failure criterion in plane stress was confirmed. Besides, a simple description of damage development in plane stress was suggested. (orig./RF)

  3. Effects of food on cortisol and mood in vulnerable subjects under controllable and uncontrollable stress

    NARCIS (Netherlands)

    Markus, R.; Panhuysen, G.; Tuiten, A.; Koppeschaar, H.

    2000-01-01

    The aim of this study was to investigate whether in stress-prone subjects, carbohydrate-rich, protein-poor food (CR/PP) diminished depressive mood and a cortisol response under controllable as well as uncontrollable laboratory stress. Twenty-two subjects with high stress proneness (HS) and 23

  4. Oxidative stress in hepatitis C infected end-stage renal disease subjects

    Directory of Open Access Journals (Sweden)

    Koylu Ahmet O

    2006-07-01

    Full Text Available Abstract Background Both uremia and hepatitis C infection is associated with increased oxidative stress. In the present study, we aimed to find out whether hepatitis C infection has any impact on oxidative stress in hemodialysis subjects. Methods Sixteen hepatitis C (+ hemodialysis subjects, 24 hepatitis C negative hemodialysis subjects and 24 healthy subjects were included. Total antioxidant capacity, total peroxide level and oxidative stress index were determined in all subjects. Results Total antioxidant capacity was significantly higher in controls than hemodialysis subjects with or without hepatitis C infection (all p 0.05/3. Conclusion Oxidative stress is increased in both hepatitis C (+ and hepatitis C (- hemodialysis subjects. However, hepatitis C infection seems to not cause any additional increase in oxidative stress in hemodialysis subjects and it may be partly due to protective effect of dialysis treatment on hepatitis C infection.

  5. A closed-loop hybrid physiological model relating to subjects under physical stress.

    Science.gov (United States)

    El-Samahy, Emad; Mahfouf, Mahdi; Linkens, Derek A

    2006-11-01

    The objective of this research study is to derive a comprehensive physiological model relating to subjects under physical stress conditions. The model should describe the behaviour of the cardiovascular system, respiratory system, thermoregulation and brain activity in response to physical workload. An experimental testing rig was built which consists of recumbent high performance bicycle for inducing the physical load and a data acquisition system comprising monitors and PCs. The signals acquired and used within this study are the blood pressure, heart rate, respiration, body temperature, and EEG signals. The proposed model is based on a grey-box based modelling approach which was used because of the sufficient level of details it provides. Cardiovascular and EEG Data relating to 16 healthy subject volunteers (data from 12 subjects were used for training/validation and the data from 4 subjects were used for model testing) were collected using the Finapres and the ProComp+ monitors. For model validation, residual analysis via the computing of the confidence intervals as well as related histograms was performed. Closed-loop simulations for different subjects showed that the model can provide reliable predictions for heart rate, blood pressure, body temperature, respiration, and the EEG signals. These findings were also reinforced by the residual analyses data obtained, which suggested that the residuals were within the 90% confidence bands and that the corresponding histograms were of a normal distribution. A higher intelligent level was added to the model, based on neural networks, to extend the capabilities of the model to predict over a wide range of subjects dynamics. The elicited physiological model describing the effect of physiological stress on several physiological variables can be used to predict performance breakdown of operators in critical environments. Such a model architecture lends itself naturally to exploitation via feedback control in a 'reverse

  6. Multiple-Input Subject-Specific Modeling of Plasma Glucose Concentration for Feedforward Control.

    Science.gov (United States)

    Kotz, Kaylee; Cinar, Ali; Mei, Yong; Roggendorf, Amy; Littlejohn, Elizabeth; Quinn, Laurie; Rollins, Derrick K

    2014-11-26

    The ability to accurately develop subject-specific, input causation models, for blood glucose concentration (BGC) for large input sets can have a significant impact on tightening control for insulin dependent diabetes. More specifically, for Type 1 diabetics (T1Ds), it can lead to an effective artificial pancreas (i.e., an automatic control system that delivers exogenous insulin) under extreme changes in critical disturbances. These disturbances include food consumption, activity variations, and physiological stress changes. Thus, this paper presents a free-living, outpatient, multiple-input, modeling method for BGC with strong causation attributes that is stable and guards against overfitting to provide an effective modeling approach for feedforward control (FFC). This approach is a Wiener block-oriented methodology, which has unique attributes for meeting critical requirements for effective, long-term, FFC.

  7. Rivulet flow round a horizontal cylinder subject to a uniform surface shear stress

    KAUST Repository

    Paterson, C.; Wilson, S. K.; Duffy, B. R.

    2014-01-01

    large stationary horizontal cylinder subject to a prescribed uniform azimuthal surface shear stress is investigated. In particular, we focus on the case where the volume flux is downwards but the shear stress is upwards, for which there is always a

  8. Social stress in young people with specific language impairment

    OpenAIRE

    Wadman, Ruth; Durkin, Kevin; Conti-Ramsden, Gina

    2010-01-01

    Social interactions can be a source of social stress for adolescents. Little is known about how adolescents with developmental difficulties, such as specific language impairment (SLI), feel when interacting socially. Participants included 28 adolescents with SLI and 28 adolescents with typical language abilities (TL). Self-report measures of social stress, social skills and social acceptance were obtained. Participants with SLI reported experiencing significantly more social stress than did p...

  9. Intake, physiological parameters and behavior of Angus and Nellore bulls subjected to heat stress

    Directory of Open Access Journals (Sweden)

    Ériton Egidio Lisboa Valente

    2015-12-01

    Full Text Available Genetics differences between breeds may determine the tolerance to high temperature, effect dry matter intake and consequently cattle performance. The effect of temperature and humidity index (THI on diurnal, nocturnal and daily intake, water intake, physiologic parameters and behavior of Nellore (B. indicus and Angus (B. taurus bulls were evaluated. Eight Angus and eight Nellore young bulls (337±7.4 kg and 16 months of age were allocated in two climate-controlled rooms for 32 days. In the period 1, all bulls were housed in thermoneutral conditions (TN, THI = 72.6 for 10 days. In period 2 (10 days, four Angus and four Nellore bulls were subjected to low heat stress (LHS, THI = 76.4 in daytime, and four Angus and four Nellore bulls were subjected to high heat stress (HHS, THI = 81.5 in daytime. The diurnal and daily dry matter intake (DMI of Nellore were not affected (P>0.05 by heat stress. However, Angus bulls decreased diurnal DMI by 24% and daily DMI decreased (P<0.05 by 15% on HHS. In TN Angus bulls had higher (P<0.05 daily DMI (36.2 g/kg of BW than Nellore (29.1 g/kg of BW, but in HHS they had similar (P>0.05 daily DMI (31.6 and 30.2 g/kg of BW, respectively. We observed an increase (P<0.05 in respiratory frequency, but water intake was not affected (P>0.05 by heat stress. The heart rate decreased (P<0.05 with heat stress. No differences were found (P>0.05 in feeding behavior. Therefore, THI stress threshold should distinct for Angus and Nellore bulls. The use of feed intake information may improve the prediction of thermic discomfort on specific climate condition. 

  10. Gender Specific Differences in the Perceived Antecedents of Academic Stress.

    Science.gov (United States)

    Jones, Russell W.

    This document consists of the report of a study undertaken to establish the existence of any gender specific differences in the perceived antecedents of academic stress. The definition of stress as a negative emotion strongly associated with doubt about coping is suggested to be particularly relevant to the academic arena where students…

  11. Similar cold stress induces sex-specific neuroendocrine and working memory responses.

    Science.gov (United States)

    Solianik, Rima; Skurvydas, Albertas; Urboniene, Daiva; Eimantas, Nerijus; Daniuseviciute, Laura; Brazaitis, Marius

    2015-01-01

    Men have higher cold-induced neuroendocrine response than women; nevertheless, it is not known whether a different stress hormone rise elicits different effects on cognition during whole body cooling. The objective was to compare the effect of cold-induced neuroendocrine responses on the performance of working memory sensitive tasks between men and women. The cold stress continued until rectal temperature reached 35.5 degree C or for a maximum of 170 min. Working memory performance and stress hormone concentrations were monitored. During cold stress, body temperature variables dropped in all subjects (P < 0.001) and did not differ between sexes. Cold stress raised plasma epinephrine and serum cortisol levels only in men (P < 0.05). Cold stress adversely affected memory performance in men but not in women (P < 0.05). The present study indicated that similar moderate cold stress in men and women induces sex-specific neuroendocrine and working memory responses.

  12. Oxidative stress in hepatitis C infected end-stage renal disease subjects.

    Science.gov (United States)

    Horoz, Mehmet; Bolukbas, Cengiz; Bolukbas, Filiz F; Aslan, Mehmet; Koylu, Ahmet O; Selek, Sahbettin; Erel, Ozcan

    2006-07-14

    Both uremia and hepatitis C infection is associated with increased oxidative stress. In the present study, we aimed to find out whether hepatitis C infection has any impact on oxidative stress in hemodialysis subjects. Sixteen hepatitis C (+) hemodialysis subjects, 24 hepatitis C negative hemodialysis subjects and 24 healthy subjects were included. Total antioxidant capacity, total peroxide level and oxidative stress index were determined in all subjects. Total antioxidant capacity was significantly higher in controls than hemodialysis subjects with or without hepatitis C infection (all p total peroxide level and oxidative stress index were significantly lower (all p total antioxidant capacity compared to hepatitis C (+) hemodialysis subjects (all p Total peroxide level and oxidative stress index was comparable between hemodialysis subjects with or without hepatitis C infection (p > 0.05/3). Oxidative stress is increased in both hepatitis C (+) and hepatitis C (-) hemodialysis subjects. However, hepatitis C infection seems to not cause any additional increase in oxidative stress in hemodialysis subjects and it may be partly due to protective effect of dialysis treatment on hepatitis C infection.

  13. Oxidative stress among subjects with metabolic syndrome in Sokoto ...

    African Journals Online (AJOL)

    2015-08-20

    Aug 20, 2015 ... Background: Oxidative stress is known to play a role in the ... others to remix, tweak, and build upon the work non-commercially, as long as the ..... Report of the National Heart, Lung, and Blood Institute/American Heart.

  14. Sex-specific mechanisms for responding to stress.

    Science.gov (United States)

    Bangasser, Debra A; Wicks, Brittany

    2017-01-02

    Posttraumatic stress disorder and major depression share stress as an etiological contributor and are more common in women than in men. Traditionally, preclinical studies investigating the neurobiological underpinnings of stress vulnerability have used only male rodents; however, recent studies that include females are finding sex-specific mechanisms for responding to stress. This Mini-Review examines recent literature using a framework developed by McCarthy and colleagues (2012; J Neurosci 32:2241-2247) that highlights different types of sex differences. First, we detail how learned fear responses in rats are sexually dimorphic. Then, we contrast this finding with fear extinction, which is similar in males and females at the behavioral level but at the circuitry level is associated with sex-specific cellular changes and, thus, exemplifies a sex convergence. Next, sex differences in stress hormones are detailed. Finally, the effects of stress on learning, attention, and arousal are used to highlight the concept of a sex divergence in which the behavior of males and females is similar at baseline but diverges following stressor exposure. We argue that appreciating and investigating the diversity of sex differences in stress response systems will improve our understanding of vulnerability and resilience to stress-related psychiatric disorders and likely lead to the development of novel therapeutics for better treatment of these disorders in both men and women. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  15. Double- and Triple-Duty Caregiving Men: An Examination of Subjective Stress and Perceived Schedule Control.

    Science.gov (United States)

    DePasquale, Nicole; Zarit, Steven H; Mogle, Jacqueline; Moen, Phyllis; Hammer, Leslie B; Almeida, David M

    2018-04-01

    Based on the stress process model of family caregiving, this study examined subjective stress appraisals and perceived schedule control among men employed in the long-term care industry (workplace-only caregivers) who concurrently occupied unpaid family caregiving roles for children (double-duty child caregivers), older adults (double-duty elder caregivers), and both children and older adults (triple-duty caregivers). Survey responses from 123 men working in nursing home facilities in the United States were analyzed using multiple linear regression models. Results indicated that workplace-only and double- and triple-duty caregivers' appraised primary stress similarly. However, several differences emerged with respect to secondary role strains, specifically work-family conflict, emotional exhaustion, and turnover intentions. Schedule control also constituted a stress buffer for double- and triple-duty caregivers, particularly among double-duty elder caregivers. These findings contribute to the scarce literature on double- and triple-duty caregiving men and have practical implications for recruitment and retention strategies in the health care industry.

  16. Compartment specific importance of glutathione during abiotic and biotic stress

    Directory of Open Access Journals (Sweden)

    Bernd eZechmann

    2014-10-01

    Full Text Available The tripeptide thiol glutathione (γ-L-glutamyl-L-cysteinyl-glycine is the most important sulfur containing antioxidant in plants and essential for plant defense against abiotic and biotic stress conditions. It is involved in the detoxification of reactive oxygen species, redox signaling, the modulation of defense gene expression and important for the regulation of enzymatic activities. Even though changes in glutathione contents are well documented in plants and its roles in plant defense are well established, still too little is known about its compartment specific importance during abiotic and biotic stress conditions. Due to technical advances in the visualization of glutathione and the redox state of plants through microscopical methods some progress was made in the last few years in studying the importance of subcellular glutathione contents during stress conditions in plants. This review summarizes the data available on compartment specific importance of glutathione in the protection against abiotic and biotic stress conditions such as high light stress, exposure to cadmium, drought, and pathogen attack (Pseudomonas, Botrytis, Tobacco Mosaic Virus. The data will be discussed in connection with the subcellular accumulation of ROS during these conditions and glutathione synthesis which are both highly compartment specific (e.g. glutathione synthesis takes place in chloroplasts and the cytosol. Thus this review will reveal the compartment specific importance of glutathione during abiotic and biotic stress conditions.

  17. Specific histone modification responds to arsenic-induced oxidative stress

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Lu [Department of Toxicology, Guangzhou Key Laboratory of Environmental Pollution and Health Risk Assessment, School of Public Health, Sun Yat-sen University, Guangzhou (China); Li, Jun [Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Department of Toxicology, School of Public Health, Guizhou Medical University, Guiyang, Guizhou (China); Zhan, Zhengbao; Chen, Liping; Li, Daochuan; Bai, Qing; Gao, Chen; Li, Jie; Zeng, Xiaowen; He, Zhini; Wang, Shan; Xiao, Yongmei [Department of Toxicology, Guangzhou Key Laboratory of Environmental Pollution and Health Risk Assessment, School of Public Health, Sun Yat-sen University, Guangzhou (China); Chen, Wen, E-mail: chenwen@mail.sysu.edu.cn [Department of Toxicology, Guangzhou Key Laboratory of Environmental Pollution and Health Risk Assessment, School of Public Health, Sun Yat-sen University, Guangzhou (China); Zhang, Aihua, E-mail: aihuagzykd@163.com [Key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Department of Toxicology, School of Public Health, Guizhou Medical University, Guiyang, Guizhou (China)

    2016-07-01

    To explore whether specific histone modifications are associated with arsenic-induced oxidative damage, we recruited 138 arsenic-exposed and arsenicosis subjects from Jiaole Village, Xinren County of Guizhou province, China where the residents were exposed to arsenic from indoor coal burning. 77 villagers from Shang Batian Village that were not exposed to high arsenic coal served as the control group. The concentrations of urine and hair arsenic in the arsenic-exposure group were 2.4-fold and 2.1-fold (all P < 0.001) higher, respectively, than those of the control group. Global histone modifications in human peripheral lymphocytes (PBLCs) were examined by ELISA. The results showed that altered global levels of H3K18ac, H3K9me2, and H3K36me3 correlated with both urinary and hair-arsenic levels of the subjects. Notably, H3K36me3 and H3K18ac modifications were associated with urinary 8-OHdG (H3K36me3: β = 0.16; P = 0.042, H3K18ac: β = − 0.24; P = 0.001). We also found that the modifications of H3K18ac and H3K36me3 were enriched in the promoters of oxidative stress response (OSR) genes in human embryonic kidney (HEK) cells and HaCaT cells, providing evidence that H3K18ac and H3K36me3 modifications mediate transcriptional regulation of OSR genes in response to NaAsO{sub 2} treatment. Particularly, we found that reduced H3K18ac modification correlated with suppressed expression of OSR genes in HEK cells with long term arsenic treatment and in PBLCs of all the subjects. Taken together, we reveal a critical role for specific histone modification in response to arsenic-induced oxidative damage. - Highlights: • H3K18ac, H3K9me2 and H3K36me3 were associated with arsenic exposed levels. • H3K18ac and H3K36me3 were correlated with oxidative damage induced by arsenic. • H3K18ac and H3K36me3 might involve in transcriptional regulation of OSR genes. • Dysregulation of H3K18ac and H3K36me3 might be biomarkers of arsenic toxicity.

  18. Specific histone modification responds to arsenic-induced oxidative stress

    International Nuclear Information System (INIS)

    Ma, Lu; Li, Jun; Zhan, Zhengbao; Chen, Liping; Li, Daochuan; Bai, Qing; Gao, Chen; Li, Jie; Zeng, Xiaowen; He, Zhini; Wang, Shan; Xiao, Yongmei; Chen, Wen; Zhang, Aihua

    2016-01-01

    To explore whether specific histone modifications are associated with arsenic-induced oxidative damage, we recruited 138 arsenic-exposed and arsenicosis subjects from Jiaole Village, Xinren County of Guizhou province, China where the residents were exposed to arsenic from indoor coal burning. 77 villagers from Shang Batian Village that were not exposed to high arsenic coal served as the control group. The concentrations of urine and hair arsenic in the arsenic-exposure group were 2.4-fold and 2.1-fold (all P < 0.001) higher, respectively, than those of the control group. Global histone modifications in human peripheral lymphocytes (PBLCs) were examined by ELISA. The results showed that altered global levels of H3K18ac, H3K9me2, and H3K36me3 correlated with both urinary and hair-arsenic levels of the subjects. Notably, H3K36me3 and H3K18ac modifications were associated with urinary 8-OHdG (H3K36me3: β = 0.16; P = 0.042, H3K18ac: β = − 0.24; P = 0.001). We also found that the modifications of H3K18ac and H3K36me3 were enriched in the promoters of oxidative stress response (OSR) genes in human embryonic kidney (HEK) cells and HaCaT cells, providing evidence that H3K18ac and H3K36me3 modifications mediate transcriptional regulation of OSR genes in response to NaAsO 2 treatment. Particularly, we found that reduced H3K18ac modification correlated with suppressed expression of OSR genes in HEK cells with long term arsenic treatment and in PBLCs of all the subjects. Taken together, we reveal a critical role for specific histone modification in response to arsenic-induced oxidative damage. - Highlights: • H3K18ac, H3K9me2 and H3K36me3 were associated with arsenic exposed levels. • H3K18ac and H3K36me3 were correlated with oxidative damage induced by arsenic. • H3K18ac and H3K36me3 might involve in transcriptional regulation of OSR genes. • Dysregulation of H3K18ac and H3K36me3 might be biomarkers of arsenic toxicity.

  19. Factors of subjective heat stress of urban citizens in contexts of everyday life

    Science.gov (United States)

    Kunz-Plapp, Tina; Hackenbruch, Julia; Schipper, Janus Willem

    2016-04-01

    Heat waves and the consequent heat stress of urban populations have a growing relevance in urban risk management and strategies of urban adaptation to climate change. In this context, social science studies on subjective experiencing of heat as stress by urban citizens are a new emerging field. To contribute to the understanding of self-reported subjective heat stress and its major determinants in a daily life perspective, we conducted a questionnaire survey with 323 respondents in Karlsruhe, Germany, after heat waves in July and August 2013. Statistical data analysis showed that subjective heat stress is an issue permeating everyday activities. Subjective heat stress at home was lower than at work and in general. Subjective heat stress in general, at home, and at work was determined by the health impairments experienced during the heat and the feeling of being helplessly exposed to the heat. For subjective heat stress at home, characteristics of the residential building and the built environment additionally played a role. Although the rate of implemented coping measures was rather high, coping measures showed no uniform effect for the subjective heat stress. We conclude that in terms of urban adaptation strategies, further research is needed to understand how various processes of daily social (work) life enable or limit individual coping and that communication strategies are important for building capacities to better cope with future heat waves.

  20. Compatible solutes in lactic acid bacteria subjected to water stress

    NARCIS (Netherlands)

    Kets, E.P.W.

    1997-01-01

    The goal of the research project described in this thesis was to investigate the protective effect of compatible solutes on tactic acid bacteria subjected to drying. Dried preparations of lactic acid bacteria are applied as starter cultures in feed and food industries. Dried starter

  1. A Computational Framework to Optimize Subject-Specific Hemodialysis Blood Flow Rate to Prevent Intimal Hyperplasia

    Science.gov (United States)

    Mahmoudzadeh, Javid; Wlodarczyk, Marta; Cassel, Kevin

    2017-11-01

    Development of excessive intimal hyperplasia (IH) in the cephalic vein of renal failure patients who receive chronic hemodialysis treatment results in vascular access failure and multiple treatment complications. Specifically, cephalic arch stenosis (CAS) is known to exacerbate hypertensive blood pressure, thrombosis, and subsequent cardiovascular incidents that would necessitate costly interventional procedures with low success rates. It has been hypothesized that excessive blood flow rate post access maturation which strongly violates the venous homeostasis is the main hemodynamic factor that orchestrates the onset and development of CAS. In this article, a computational framework based on a strong coupling of computational fluid dynamics (CFD) and shape optimization is proposed that aims to identify the effective blood flow rate on a patient-specific basis that avoids the onset of CAS while providing the adequate blood flow rate required to facilitate hemodialysis. This effective flow rate can be achieved through implementation of Miller's surgical banding method after the maturation of the arteriovenous fistula and is rooted in the relaxation of wall stresses back to a homeostatic target value. The results are indicative that this optimized hemodialysis blood flow rate is, in fact, a subject-specific value that can be assessed post vascular access maturation and prior to the initiation of chronic hemodialysis treatment as a mitigative action against CAS-related access failure. This computational technology can be employed for individualized dialysis treatment.

  2. Evaluation of oxidative stress in mice subjected to aerobic exercise.

    Science.gov (United States)

    Lima, Mônica Cruvinel de; Marks, Guido; Silva, Iandara Schettert; Silva, Baldomero Antonio Kato da; Cônsolo, Lourdes Zélia Zanoni; Nogueira, Gabriel Bogalho

    2012-08-01

    To evaluate the influence of aerobic exercise on oxidative stress in mice. The study included twenty female mice Mus musculus-Swiss divided into two groups: sedentary control (GA) and exercise (GB), each containing ten animals. All animals underwent an adaptation period of seven days isolated in individual boxes. After this period, the animals in the exercise group (GB) were trained in angled running wheel with circumference of 25 cm assembled on an articulated axle during five minutes for three consecutive days. On the fourth day, they underwent an exercise program of one session lasting 45 minutes. The evaluation of oxidative stress was performed by determining the levels of malondialhyde derived of lipid peroxidation by the TBA method. The samples were read in a spectrophotometer at 535 nm. No significant difference was observed in the intergroup comparison of MDA levels in the tissues evaluated. A significant difference was observed in the intragroup comparison of MDA levels in the control group (p = 0.0201).The Tukeys' post hoc test indicated significantly lower values of MDA in the smooth muscle in relation to plasma. In the analysis of variance in the exercise group, a significant difference between tissues (p = 0.0009), with significantly lower values in the smooth muscle in relation to plasma (pstress in mice which were undergone a single session of aerobic exercise.

  3. Statistical damage constitutive model for rocks subjected to cyclic stress and cyclic temperature

    Science.gov (United States)

    Zhou, Shu-Wei; Xia, Cai-Chu; Zhao, Hai-Bin; Mei, Song-Hua; Zhou, Yu

    2017-10-01

    A constitutive model of rocks subjected to cyclic stress-temperature was proposed. Based on statistical damage theory, the damage constitutive model with Weibull distribution was extended. Influence of model parameters on the stress-strain curve for rock reloading after stress-temperature cycling was then discussed. The proposed model was initially validated by rock tests for cyclic stress-temperature and only cyclic stress. Finally, the total damage evolution induced by stress-temperature cycling and reloading after cycling was explored and discussed. The proposed constitutive model is reasonable and applicable, describing well the stress-strain relationship during stress-temperature cycles and providing a good fit to the test results. Elastic modulus in the reference state and the damage induced by cycling affect the shape of reloading stress-strain curve. Total damage induced by cycling and reloading after cycling exhibits three stages: initial slow increase, mid-term accelerated increase, and final slow increase.

  4. Normal stress databases in myocardial perfusion scintigraphy – how many subjects do you need?

    DEFF Research Database (Denmark)

    Trägårdh, Elin; Sjöstrand, Karl; Edenbrandt, Lars

    2012-01-01

    ) for male, NC for female, attenuation‐corrected images (AC) for male and AC for female subjects. 126 male and 205 female subjects were included. The normal database was created by alternatingly computing the mean of all normal subjects and normalizing the subjects with respect to this mean, until...... convergence. Coefficients of variation (CV) were created for increasing number of included patients in the four different normal stress databases. Normal stress databases with ...Commercial normal stress databases in myocardial perfusion scintigraphy (MPS) commonly consist of 30–40 individuals. The aim of the study was to determine how many subjects are needed. Four normal stress databases were developed using patients who underwent 99mTc MPS: non‐corrected images (NC...

  5. Salivary alpha amylase activity in human beings of different age groups subjected to psychological stress.

    Science.gov (United States)

    Sahu, Gopal K; Upadhyay, Seema; Panna, Shradha M

    2014-10-01

    Salivary alpha-amylase (sAA) has been proposed as a sensitive non-invasive biomarker for stress-induced changes in the body that reflect the activity of the sympathetic nervous system. Though several experiments have been conducted to determine the validity of this salivary component as a reliable stress marker in human subjects, the effect of stress induced changes on sAA level in different age groups is least studied. This article reports the activity of sAA in human subjects of different age groups subjected to psychological stress induced through stressful video clip. Differences in sAA level based on sex of different age groups under stress have also been studied. A total of 112 subjects consisting of both the male and female subjects, divided into two groups on basis of age were viewed a video clip of corneal transplant surgery as stressor. Activity of sAA from saliva samples of the stressed subjects were measured and compared with the activity of the samples collected from the subjects before viewing the clip. The age ranges of subjects were 18-25 and 40-60 years. The sAA level increased significantly in both the groups after viewing the stressful video. The increase was more pronounced in the younger subjects. The level of sAA was comparatively more in males than females in the respective groups. No significant change in sAA activity was observed after viewing the soothed video clip. Significant increase of sAA level in response to psychological stress suggests that it might act as a reliable sympathetic activity biochemical marker in different stages of human beings.

  6. Examining coping style and the relationship between stress and subjective well-being in Australia's 'sandwich generation'.

    Science.gov (United States)

    Gillett, Jade E; Crisp, Dimity A

    2017-09-01

    The sandwich generation represents adults, often in midlife, who care for both children and ageing parents/relatives. While the stress they experience has received some attention, little research has investigated the subjective well-being (SWB) of this population. This study examined the relationship between perceived stress and SWB and the moderating effect of coping style. Ninety-three participants (80 women), aged 23-63 years, completed an online survey measuring perceived stress, coping strategies, life satisfaction and positive and negative affect. Stress was negatively associated with SWB. While emotion- and problem-focused coping were directly associated with SWB outcomes, the only moderating effect found was for avoidance-focused coping (AFC). Specifically, AFC was associated with higher positive affect for those reporting lower stress. This study highlights the need to recognise the distinct circumstances that exist for the sandwich generation. Limitations and suggestions for future research are discussed. © 2017 AJA Inc.

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

    Science.gov (United States)

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

    2013-02-01

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

  8. Sex differences in objective measures of sleep in post-traumatic stress disorder and healthy control subjects.

    Science.gov (United States)

    Richards, Anne; Metzler, Thomas J; Ruoff, Leslie M; Inslicht, Sabra S; Rao, Madhu; Talbot, Lisa S; Neylan, Thomas C

    2013-12-01

    A growing literature shows prominent sex effects for risk for post-traumatic stress disorder and associated medical comorbid burden. Previous research indicates that post-traumatic stress disorder is associated with reduced slow wave sleep, which may have implications for overall health, and abnormalities in rapid eye movement sleep, which have been implicated in specific post-traumatic stress disorder symptoms, but most research has been conducted in male subjects. We therefore sought to compare objective measures of sleep in male and female post-traumatic stress disorder subjects with age- and sex-matched control subjects. We used a cross-sectional, 2 × 2 design (post-traumatic stress disorder/control × female/male) involving83 medically healthy, non-medicated adults aged 19-39 years in the inpatient sleep laboratory. Visual electroencephalographic analysis demonstrated that post-traumatic stress disorder was associated with lower slow wave sleep duration (F(3,82)  = 7.63, P = 0.007) and slow wave sleep percentage (F(3,82)  = 6.11, P = 0.016). There was also a group × sex interaction effect for rapid eye movement sleep duration (F(3,82)  = 4.08, P = 0.047) and rapid eye movement sleep percentage (F(3,82)  = 4.30, P = 0.041), explained by greater rapid eye movement sleep in post-traumatic stress disorder females compared to control females, a difference not seen in male subjects. Quantitative electroencephalography analysis demonstrated that post-traumatic stress disorder was associated with lower energy in the delta spectrum (F(3,82)  = 6.79, P = 0.011) in non-rapid eye movement sleep. Slow wave sleep and delta findings were more pronounced in males. Removal of post-traumatic stress disorder subjects with comorbid major depressive disorder, who had greater post-traumatic stress disorder severity, strengthened delta effects but reduced rapid eye movement effects to non-significance. These findings support previous evidence that post

  9. Social Stress in Young People with Specific Language Impairment

    Science.gov (United States)

    Wadman, Ruth; Durkin, Kevin; Conti-Ramsden, Gina

    2011-01-01

    Social interactions can be a source of social stress for adolescents. Little is known about how adolescents with developmental difficulties, such as specific language impairment (SLI), feel when interacting socially. Participants included 28 adolescents with SLI and 28 adolescents with typical language abilities (TL). Self-report measures of…

  10. Specifications for Supplementary Classroom Units, Stressed Skin Panel.

    Science.gov (United States)

    Waring, Robert B.; And Others

    Complete outline specifications are given for the construction of supplementary classroom units using stressed skin panels. Sections included are--(1) concrete and related work, (2) masonry, (3) structural and miscellaneous metal, (4) curtain walls and metal windows, (5) carpentry and related work, (6) roofing, sheet metal, and related work, (7)…

  11. Probiotics, D–Lactic acidosis, oxidative stress and strain specificity

    Science.gov (United States)

    2017-01-01

    ABSTRACT The existence of an implicit living microscopic world, composed primarily of bacteria, has been known for centuries. The exact mechanisms that govern the contribution of bacteria to human health and disease have only recently become the subject of intense research efforts. Within this very evident shift in paradigms, the rational design of probiotic formulations has led to the creation of an industry that seeks to progress the engineering of probiotic bacteria that produce metabolites that may enhance human host health and prevent disease. The promotion of probiotics is often made in the absence of quality scientific and clinically plausible data. The latest incursions into the probiotic market of claims have posited the amelioration of oxidative stress via potent antioxidant attributes or limiting the administration of probiotics to those species that do not produce D-Lactic acid (i.e., claims that D-Lactic acid acidosis is linked to chronic health conditions) or are strain-specific (shaping an industry point of difference) for appraising a therapeutic effect. Evidence-based research should guide clinical practice, as there is no place in science and medicine that supports unsubstantiated claims. Extravagant industry based notions continue to fuel the imprimatur of distrust and skepticism that is leveled by scientists and clinicians at an industry that is already rife with scientific and medical distrust and questionable views on probiotics. Ignoring scientifically discordant data, when sorting through research innovations and false leads relevant to the actions of probiotics, drives researcher discomfit and keeps the bar low, impeding the progress of knowledge. Biologically plausible posits are obligatory in any research effort; companies formulating probiotics often exhibit a lack of analytical understanding that then fuels questionable investigations failing to build on research capacity. PMID:28080206

  12. Probiotics, D-Lactic acidosis, oxidative stress and strain specificity.

    Science.gov (United States)

    Vitetta, Luis; Coulson, Samantha; Thomsen, Michael; Nguyen, Tony; Hall, Sean

    2017-07-04

    The existence of an implicit living microscopic world, composed primarily of bacteria, has been known for centuries. The exact mechanisms that govern the contribution of bacteria to human health and disease have only recently become the subject of intense research efforts. Within this very evident shift in paradigms, the rational design of probiotic formulations has led to the creation of an industry that seeks to progress the engineering of probiotic bacteria that produce metabolites that may enhance human host health and prevent disease. The promotion of probiotics is often made in the absence of quality scientific and clinically plausible data. The latest incursions into the probiotic market of claims have posited the amelioration of oxidative stress via potent antioxidant attributes or limiting the administration of probiotics to those species that do not produce D-Lactic acid (i.e., claims that D-Lactic acid acidosis is linked to chronic health conditions) or are strain-specific (shaping an industry point of difference) for appraising a therapeutic effect. Evidence-based research should guide clinical practice, as there is no place in science and medicine that supports unsubstantiated claims. Extravagant industry based notions continue to fuel the imprimatur of distrust and skepticism that is leveled by scientists and clinicians at an industry that is already rife with scientific and medical distrust and questionable views on probiotics. Ignoring scientifically discordant data, when sorting through research innovations and false leads relevant to the actions of probiotics, drives researcher discomfit and keeps the bar low, impeding the progress of knowledge. Biologically plausible posits are obligatory in any research effort; companies formulating probiotics often exhibit a lack of analytical understanding that then fuels questionable investigations failing to build on research capacity.

  13. Optimal Multitrial Prediction Combination and Subject-Specific Adaptation for Minimal Training Brain Switch Designs

    NARCIS (Netherlands)

    Spyrou, L.; Blokland, Y.M.; Farquhar, J.D.R.; Bruhn, J.

    2016-01-01

    Brain-Computer Interface (BCI) systems are traditionally designed by taking into account user-specific data to enable practical use. More recently, subject independent (SI) classification algorithms have been developed which bypass the subject specific adaptation and enable rapid use of the system.

  14. Optimal multitrial prediction combination and subject-specific adaptation for minimal training brain switch designs

    NARCIS (Netherlands)

    Spyrou, L.; Blokland, Y.M.; Farquhar, J.D.R.; Bruhn, J.

    2016-01-01

    Brain-Computer Interface systems are traditionally designed by taking into account user-specific data to enable practical use. More recently, subject independent (SI) classification algorithms have been developed which bypass the subject specific adaptation and enable rapid use of the system. A

  15. Reliability of mechanical components subjected to combined alternating and mean stresses with a nonconstant stress ratio

    International Nuclear Information System (INIS)

    Kececioglu, D.; Lamarre, G.B.

    1979-01-01

    The reliability of reactor mechanical components and structural members, submitted to external loads which induce alternating bending stresses and mean shear stresses at the critical section where failure has a high probability of occurring, is predicted assuming that the ratio of the distributed alternating stress to the mean stress is also distributed and yields a bivariate failure-governing, combined alternating and mean, stress distribution. A computer programmed methodology is developed to calculate the reliability under these conditions given the associated distributional Goodman diagram for a reactor component or structural member. (orig.)

  16. Drought stress had a predominant effect over heat stress on three tomato cultivars subjected to combined

    DEFF Research Database (Denmark)

    Zhou, Rong; Yu, Xiaqing; Ottosen, Carl-Otto

    2017-01-01

    and relative water content of all cultivars significantly decreased under drought and combined stress as compared to control. The net photosynthesis and starch content were significantly lower under drought and combined stress than control in the three cultivars. Stomata and pore length of the three cultivars......BACKGROUND: Abiotic stresses due to environmental factors could adversely affect the growth and development of crops. Among the abiotic stresses, drought and heat stress are two critical threats to crop growth and sustainable agriculture worldwide. Considering global climate change, incidence...... of combined drought and heat stress is likely to increase. The aim of this study was to shed light on plant growth performance and leaf physiology of three tomatoes cultivars ('Arvento', 'LA1994' and 'LA2093') under control, drought, heat and combined stress. RESULTS: Shoot fresh and dry weight, leaf area...

  17. Serum prolidase enzyme activity in obese subjects and its relationship with oxidative stress markers.

    Science.gov (United States)

    Aslan, Mehmet; Duzenli, Ufuk; Esen, Ramazan; Soyoral, Yasemin Usul

    2017-10-01

    The relationship between increased serum enzyme activity of prolidase and increased rate of collagen turnover in the arterial wall has been asserted in previous studies. Collagen reflects much of the strength to the connective tissue involved in the arterial wall. Atherosclerosis is very common vessel disease and oxidative stress plays a pivotal role in the etiopathogenesis. Our objective was to examine the serum enzyme activity of prolidase and its possible relationships with oxidative stress parameters in obese subjects. Our present study was conducted 27 obese subjects and 26 age-matched healthy control subjects. The serum enzyme activity of prolidase in all study population was evaluated spectrophotometrically. Oxidative stress levels in obese subjects were analyzed with total antioxidant capacity (TAC) and total oxidant status (TOS) as well as oxidative stress index (OSI). Obese subjects have higher serum TOS and OSI indicators as well as prolidase activity than those in control subjects (for all; pstress levels in obese subjects. The significantly correlation between increased oxidative stress and increased prolidase activity may play a pivotal role in etiopathogenesis of atherosclerotic cardiovascular diseases in obese subjects. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Food stress causes sex-specific maternal effects in mites.

    Science.gov (United States)

    Walzer, Andreas; Schausberger, Peter

    2015-08-01

    Life history theory predicts that females should produce few large eggs under food stress and many small eggs when food is abundant. We tested this prediction in three female-biased size-dimorphic predatory mites feeding on herbivorous spider mite prey: Phytoseiulus persimilis, a specialized spider mite predator; Neoseiulus californicus, a generalist preferring spider mites; Amblyseius andersoni, a broad diet generalist. Irrespective of predator species and offspring sex, most females laid only one small egg under severe food stress. Irrespective of predator species, the number of female but not male eggs decreased with increasing maternal food stress. This sex-specific effect was probably due to the higher production costs of large female than small male eggs. The complexity of the response to the varying availability of spider mite prey correlated with the predators' degree of adaptation to this prey. Most A. andersoni females did not oviposit under severe food stress, whereas N. californicus and P. persimilis did oviposit. Under moderate food stress, only P. persimilis increased its investment per offspring, at the expense of egg number, and produced few large female eggs. When prey was abundant, P. persimilis decreased the female egg sizes at the expense of increased egg numbers, resulting in a sex-specific egg size/number trade-off. Maternal effects manifested only in N. californicus and P. persimilis. Small egg size correlated with the body size of daughters but not sons. Overall, our study provides a key example of sex-specific maternal effects, i.e. food stress during egg production more strongly affects the sex of the large than the small offspring. © 2015. Published by The Company of Biologists Ltd.

  19. THE STRESS RESISTANCE OF STUDENTS. THE PARADIGM OF SUBJECT PERSONALITY SELF- ORGANIZATION

    Directory of Open Access Journals (Sweden)

    Sergey I. Dyakov

    2016-01-01

    Full Text Available The aim of the investigation is to consider a problem of stress resistance of students in the context of subject self-organization of the personality. Methods. The following methods of research are used: questioning; psychological and diagnostic tests «Tolerance of Uncertainty» (NTN and «Personal Factors of Decisions» (PFD by T. V. Kornilova; original experimental experiences – «Coding», a technique of a self-assessment (scaling and «A locus control». While data processing the methods of mathematical statistics (SPSS 12 package – the correlation analysis of Pearson and the factorial analysis with rotation use a component by «verimax» method are applied. Results and scientific novelty. Types of subjectivity and strategy of stress resistance are allocated. The nature and a role of the emotional and stressful mechanism having information and semantic properties in its basis are disclosed. Communication of irresponsible mechanisms of mentality with the sphere of consciousness in the context of subjectivity of the personality is shown. Mechanisms of emotional and rational self-control of system of mental self-organization of the person are presented. The statistical and qualitative data opening communications between properties of subjectivity and stress resistance of the personality are empirically obtained. Variation of the relations and also types of subjectivity and stress resistance emphasized based on the results of the presented research. Original (author’s methods of studying of subjectivity and factors of stress resistance are presented. Practical significance. The revealed factors of subject self-organization reveal the stress-producing directions of the environment and the relation of the personality to situations of changes and uncertainty: and also indicate subject properties of resistance to stress which need to be developed to increase the level of health of students, to reduce risk of deviance and delinquency of

  20. Influence of subject choice, work overload and work stress on expatriate higher education teachers.

    OpenAIRE

    Naithani, Pranav

    2013-01-01

    Subject choice, work overload and work stress influence personal and professional lives of higher education teachers. Though the majority of higher education teachers in the Gulf Cooperation Council (GCC) countries are expatriates, yet research on expatriate higher education teachers working in the GCC countries is limited. This paper presents one part of the work life balance survey and focuses on the influence of subject choice, work overload and work stress on higher education teachers in ...

  1. Turbulent oscillating channel flow subjected to a free-surface stress.

    NARCIS (Netherlands)

    Kramer, W.; Clercx, H.J.H.; Armenio, V.

    2010-01-01

    The channel flow subjected to a wind stress at the free surface and an oscillating pressure gradient is investigated using large-eddy simulations. The orientation of the surface stress is parallel with the oscillating pressure gradient and a purely pulsating mean flow develops. The Reynolds number

  2. Sex-Specific Response to Stress in Populus

    Directory of Open Access Journals (Sweden)

    Nataliya V. Melnikova

    2017-10-01

    Full Text Available Populus is an effective model for genetic studies in trees. The genus Populus includes dioecious species, and the differences exhibited in males and females have been intensively studied. This review focused on the distinctions between male and female poplar and aspen plants under stress conditions, such as drought, salinity, heavy metals, and nutrient deficiency on morphological, physiological, proteome, and gene expression levels. In most studies, males of Populus species were more adaptive to the majority of the stress conditions and showed less damage, better growth, and higher photosynthetic capacity and antioxidant activity than that of the females. However, in two recent studies, no differences in non-reproductive traits were revealed for male and female trees. This discrepancy of the results could be associated with experimental design: different species and genotypes, stress conditions, types of plant materials, sampling sizes. Knowledge of sex-specific differences is crucial for basic and applied research in Populus species.

  3. Numerical evaluation of stress intensity factor for vessel and pipe subjected to thermal shock

    International Nuclear Information System (INIS)

    Kim, Y.W.; Lee, H.Y.; Yoo, B.

    1994-01-01

    The thermal weight function method and the finite element method were employed in the numerical computation of the stress intensity factor for a cracked vessel and the cracked pipe subjected to thermal shock. A wall subjected to thermal shock was analyzed, and it has been shown that the effect of thermal shock on the stress intensity factor is dominant for the crack with small crack length to thickness ratio. Convection at the crack face had an influence on the stress intensity factor in the early stage of thermal shock. (Author)

  4. Sex-specific selection under environmental stress in seed beetles.

    Science.gov (United States)

    Martinossi-Allibert, I; Arnqvist, G; Berger, D

    2017-01-01

    Sexual selection can increase rates of adaptation by imposing strong selection in males, thereby allowing efficient purging of the mutation load on population fitness at a low demographic cost. Indeed, sexual selection tends to be male-biased throughout the animal kingdom, but little empirical work has explored the ecological sensitivity of this sex difference. In this study, we generated theoretical predictions of sex-specific strengths of selection, environmental sensitivities and genotype-by-environment interactions and tested them in seed beetles by manipulating either larval host plant or rearing temperature. Using fourteen isofemale lines, we measured sex-specific reductions in fitness components, genotype-by-environment interactions and the strength of selection (variance in fitness) in the juvenile and adult stage. As predicted, variance in fitness increased with stress, was consistently greater in males than females for adult reproductive success (implying strong sexual selection), but was similar in the sexes in terms of juvenile survival across all levels of stress. Although genetic variance in fitness increased in magnitude under severe stress, heritability decreased and particularly so in males. Moreover, genotype-by-environment interactions for fitness were common but specific to the type of stress, sex and life stage, suggesting that new environments may change the relative alignment and strength of selection in males and females. Our study thus exemplifies how environmental stress can influence the relative forces of natural and sexual selection, as well as concomitant changes in genetic variance in fitness, which are predicted to have consequences for rates of adaptation in sexual populations. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

  5. The chromatin remodeler SPLAYED regulates specific stress signaling pathways.

    Directory of Open Access Journals (Sweden)

    Justin W Walley

    2008-12-01

    Full Text Available Organisms are continuously exposed to a myriad of environmental stresses. Central to an organism's survival is the ability to mount a robust transcriptional response to the imposed stress. An emerging mechanism of transcriptional control involves dynamic changes in chromatin structure. Alterations in chromatin structure are brought about by a number of different mechanisms, including chromatin modifications, which covalently modify histone proteins; incorporation of histone variants; and chromatin remodeling, which utilizes ATP hydrolysis to alter histone-DNA contacts. While considerable insight into the mechanisms of chromatin remodeling has been gained, the biological role of chromatin remodeling complexes beyond their function as regulators of cellular differentiation and development has remained poorly understood. Here, we provide genetic, biochemical, and biological evidence for the critical role of chromatin remodeling in mediating plant defense against specific biotic stresses. We found that the Arabidopsis SWI/SNF class chromatin remodeling ATPase SPLAYED (SYD is required for the expression of selected genes downstream of the jasmonate (JA and ethylene (ET signaling pathways. SYD is also directly recruited to the promoters of several of these genes. Furthermore, we show that SYD is required for resistance against the necrotrophic pathogen Botrytis cinerea but not the biotrophic pathogen Pseudomonas syringae. These findings demonstrate not only that chromatin remodeling is required for selective pathogen resistance, but also that chromatin remodelers such as SYD can regulate specific pathways within biotic stress signaling networks.

  6. Seed priming with hormones does not alleviate induced oxidative stress in maize seedlings subjected to salt stress

    Directory of Open Access Journals (Sweden)

    Rogério Falleiros Carvalho

    2011-10-01

    Full Text Available Seed priming with hormones has been an efficient method for increasing seed vigor as well as seedling growth under stressful conditions. These responses have in the past been attributed to the activation of antioxidant systems in a range of crops. The results described in this work show that hormonal priming with methyl jasmonate, salicylic acid or CEPA (chloroethylphosphonic acid, an ethylene (ET releaser, does not induce the antioxidant activity of superoxide dismutase, catalase, ascorbate peroxidase or glutathione reductase in maize seedlings subjected to salt stress. The enhanced biomass of maize seedlings under salt stress that was observed only from ET priming indicates that the stress tolerance in maize from ethylene priming is a fundamental process for stress tolerance acquisition, which is explained, however, by other biochemical mechanisms but not by changes in the antioxidant system.

  7. Subjectivity

    Directory of Open Access Journals (Sweden)

    Jesús Vega Encabo

    2015-11-01

    Full Text Available In this paper, I claim that subjectivity is a way of being that is constituted through a set of practices in which the self is subject to the dangers of fictionalizing and plotting her life and self-image. I examine some ways of becoming subject through narratives and through theatrical performance before others. Through these practices, a real and active subjectivity is revealed, capable of self-knowledge and self-transformation. 

  8. Atlas-Based Automatic Generation of Subject-Specific Finite Element Tongue Meshes.

    Science.gov (United States)

    Bijar, Ahmad; Rohan, Pierre-Yves; Perrier, Pascal; Payan, Yohan

    2016-01-01

    Generation of subject-specific 3D finite element (FE) models requires the processing of numerous medical images in order to precisely extract geometrical information about subject-specific anatomy. This processing remains extremely challenging. To overcome this difficulty, we present an automatic atlas-based method that generates subject-specific FE meshes via a 3D registration guided by Magnetic Resonance images. The method extracts a 3D transformation by registering the atlas' volume image to the subject's one, and establishes a one-to-one correspondence between the two volumes. The 3D transformation field deforms the atlas' mesh to generate the subject-specific FE mesh. To preserve the quality of the subject-specific mesh, a diffeomorphic non-rigid registration based on B-spline free-form deformations is used, which guarantees a non-folding and one-to-one transformation. Two evaluations of the method are provided. First, a publicly available CT-database is used to assess the capability to accurately capture the complexity of each subject-specific Lung's geometry. Second, FE tongue meshes are generated for two healthy volunteers and two patients suffering from tongue cancer using MR images. It is shown that the method generates an appropriate representation of the subject-specific geometry while preserving the quality of the FE meshes for subsequent FE analysis. To demonstrate the importance of our method in a clinical context, a subject-specific mesh is used to simulate tongue's biomechanical response to the activation of an important tongue muscle, before and after cancer surgery.

  9. Estimating the actual subject-specific genetic correlations in behavior genetics.

    Science.gov (United States)

    Molenaar, Peter C M

    2012-10-01

    Generalization of the standard behavior longitudinal genetic factor model for the analysis of interindividual phenotypic variation to a genetic state space model for the analysis of intraindividual variation enables the possibility to estimate subject-specific heritabilities.

  10. The effect of teacher interpersonal behaviour on students' subject-specific motivation

    NARCIS (Netherlands)

    Brok, den P.J.; Levy, J.; Brekelmans, J.M.G.; Wubbels, Th.

    2005-01-01

    A brief narrative description of the journal article, document, or resource. This study brings together insights from research on teaching and learning in specific subjects, learning environments research, and effectiveness research, by linking teacher interpersonal behaviour to students'

  11. When does stress help or harm? The effects of stress controllability and subjective stress response on Stroop performance.

    OpenAIRE

    Roselinde Kaiser Henderson; Hannah R. Snyder; Tina eGupta; Marie T. Banich; Marie T. Banich

    2012-01-01

    The ability to engage in goal-directed behavior despite exposure to stress is critical to resilience. Questions of how stress can impair or improve behavioral functioning are important in diverse settings, from athletic competitions to academic testing to clinical therapy. Previous research suggests that controllability is a key factor in the impact of stress on behavior: learning how to control stressors buffers people from the negative effects of stress on subsequent cognitively demanding ...

  12. When Does Stress Help or Harm? The Effects of Stress Controllability and Subjective Stress Response on Stroop Performance

    OpenAIRE

    Henderson, Roselinde K.; Snyder, Hannah R.; Gupta, Tina; Banich, Marie T.

    2012-01-01

    The ability to engage in goal-directed behavior despite exposure to stress is critical to resilience. Questions of how stress can impair or improve behavioral functioning are important in diverse settings, from athletic competitions to academic testing. Previous research suggests that controllability is a key factor in the impact of stress on behavior: learning how to control stressors buffers people from the negative effects of stress on subsequent cognitively demanding tasks. In addition, r...

  13. An analytical solution describing the shape of a yield stress material subjected to an overpressure

    DEFF Research Database (Denmark)

    Hovad, Emil; Spangenberg, Jon; Larsen, P.

    2016-01-01

    as well as the spread length and height of the material when deformed in a box due to gravity. In the present work, the analytical solution is extended with the addition of an overpressure that acts over the entire body of the material. This extension enables finding the shape of a yield stress material......Many fluids and granular materials are able to withstand a limited shear stress without flowing. These materials are known as yields stress materials. Previously, an analytical solution was presented to quantify the yield stress for such materials. The yields stress is obtained based on the density...... with known density and yield stress when for instance deformed under water or subjected to a forced air pressure....

  14. Statistics of the Von Mises Stress Response For Structures Subjected To Random Excitations

    Directory of Open Access Journals (Sweden)

    Mu-Tsang Chen

    1998-01-01

    Full Text Available Finite element-based random vibration analysis is increasingly used in computer aided engineering software for computing statistics (e.g., root-mean-square value of structural responses such as displacements, stresses and strains. However, these statistics can often be computed only for Cartesian responses. For the design of metal structures, a failure criterion based on an equivalent stress response, commonly known as the von Mises stress, is more appropriate and often used. This paper presents an approach for computing the statistics of the von Mises stress response for structures subjected to random excitations. Random vibration analysis is first performed to compute covariance matrices of Cartesian stress responses. Monte Carlo simulation is then used to perform scatter and failure analyses using the von Mises stress response.

  15. The effect of teacher interpersonal behaviour on students' subject-specific motivation

    NARCIS (Netherlands)

    den Brok, P.; Levy, J.; Brekelmans, M.; Wubbels, Th.

    2006-01-01

    This study brings together insights from research on teaching and learning in specific subjects, learning environments research and effectiveness research by linking teacher interpersonal behaviour to students’ subject-related attitudes. Teaching was studied in terms of a model originating from

  16. 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.

  17. A preliminary investigation of workplace stress in platinum miners using subjective and objective measures

    CSIR Research Space (South Africa)

    Edwards, A

    2011-04-01

    Full Text Available Workplace stress in the mining environment will affect health and safety outcomes in the workforce that could result in accidents and injuries, as well as poorer worker health. Increased knowledge of the specific characteristics and incidence...

  18. Mindfulness, perceived stress, and subjective well-being: a correlational study in primary care health professionals.

    Science.gov (United States)

    Atanes, Ana C M; Andreoni, Solange; Hirayama, Marcio S; Montero-Marin, Jesús; Barros, Viviam V; Ronzani, Telmo M; Kozasa, Eliza H; Soler, Joaquim; Cebolla, Ausiàs; Garcia-Campayo, Javier; Demarzo, Marcelo M P

    2015-09-02

    Primary health care professionals (PHPs) usually report high levels of distress and burnout symptoms related to job strain. Mindfulness, defined as non-judgmental-present-moment awareness, seems to be a moderator in the causal association between life stressors and well-being. This study aimed to verify correlations among self-reported mindfulness, perceived stress (PS), and subjective well-being (SW) in Brazilian PHPs. We performed a correlational cross-sectional study in a purposive sample of Brazilian PHPs (physicians, nurses, nursing assistants, and community health workers), working in community-oriented primary care programs (known locally as "Family Health Programs"). We used validated self-reporting instruments: the Mindful Attention Awareness Scale (MAAS), the Perceived Stress Scale (PSS), and the Subjective Well-being Scale (SWS). We performed a multivariate analysis of variance (MANOVA), through regression coefficients (beta) in relation to the professional category (nursing assistant), in addition to the length of time in the same job (under than 6 months) that had indicated the lowest level of PS. Participants (n=450) comprised community health workers (65.8%), nursing assistants (18%), registered nurses (10.0%), and doctors (family physicians) (6.0%); 94% were female and 83.1% had worked in the same position for more than one year. MANOVA regression analysis showed differences across professional categories and length of time in the same job position in relation to mindfulness, PS, and SW. Nurses demonstrated lower levels of mindfulness, higher PS, and SW negative affect, as well as lower SW positive affect. Being at work for 1 year or longer showed a clear association with higher PS and lower SW positive affect, and no significance with mindfulness levels. Pearson's coefficient values indicated strong negative correlations between mindfulness and PS, and medium correlations between mindfulness and SW. In this study, there were clear correlations

  19. Oxidised fish oil does not influence established markers of oxidative stress in healthy human subjects

    DEFF Research Database (Denmark)

    Ottestad, Inger; Vogt, Gjermund; Retterstøl, Kjetil

    2012-01-01

    markers of oxidative stress, lipid peroxidation and inflammation, and the level of plasma n-3 FA after intake of oxidised fish oil. In a double-blinded randomised controlled study, healthy subjects (aged 18–50 years, n 54) were assigned into one of three groups receiving capsules containing either 8 g...... difference was observed between the fish oil groups. No changes in a variety of in vivo markers of oxidative stress, lipid peroxidation or inflammation were observed after daily intake of oxidised fish oil for 3 or 7 weeks, indicating that intake of oxidised fish oil may not have unfavourable short......-term effects in healthy human subjects....

  20. Relationships between Psychosocial Difficulties and Oxidative Stress Biomarkers in Women Subject to Intimate Partner Violence.

    Science.gov (United States)

    Kim, Jae Yop; Lee, Ji Hyeon; Song, Hyang Joo; Kim, Dong Goo; Yim, Yeong Shin

    2017-02-01

    Women subject to violence by their intimate partners often experience a range of psychosocial problems such as depression, excessive alcohol use, and stressful life events that, in turn, lead to health issues. This study examined psychosocial difficulties and oxidative stress levels in abused and non-abused Korean women and analyzed the relationship between psychosocial outcomes and oxidative stress levels. Markers were determined in 16 women (seven abused, nine non-abused). The two groups of women (abused and non-abused) were compared with respect to scores in depression, alcohol use, life stress events, and oxidative stress biomarkers using the Mann-Whitney U test. Correlations between depression, alcohol use, life stress events, and oxidative stress biomarkers were tested by the Spearman rank correlation coefficient. The abused women had significantly higher levels of oxidative stress markers and significantly lower levels of antioxidants than the non-abused women. Life stress events and oxidative biomarker levels were significantly correlated. These findings have implications for both social services providers and medical personnel when assessing abused women to ensure that they receive the most appropriate service. © 2016 National Association of Social Workers.

  1. Biofluid metabotyping of occupationally exposed subjects to air pollution demonstrates high oxidative stress and deregulated amino acid metabolism

    Science.gov (United States)

    Pradhan, Surya Narayan; Das, Aleena; Meena, Ramovatar; Nanda, Ranjan Kumar; Rajamani, Paulraj

    2016-10-01

    Occupational exposure to air pollution induces oxidative stress and prolonged exposure increases susceptibility to cardiovascular and respiratory diseases in several working groups. Biofluid of these subjects may reflect perturbed metabolic phenotypes. In this study we carried out a comparative molecular profiling study using parallel biofluids collected from subjects (n = 85) belonging to auto rickshaw drivers (ARD), traffic cops (TC) and office workers (OW). Higher levels of oxidative stress and inflammation markers in serum of ARD subjects were observed as compared to OW and TC. Uni and multivariate analyses of metabolites identified in urine by 1H NMR revealed 11 deregulated molecules in ARD subjects and involved in phenylalanine, histidine, arginine and proline metabolism. Despite contribution of confounding factors like exposure period, dietary factors including smoking and alcohol status, our results demonstrate existence of exposure specific metabotypes in biofluids of ARD, OW and TC groups. Monitoring serum oxidative stress and inflammation markers and urine metabolites by NMR may be useful to characterize perturbed metabolic phenotypes in populations exposed to urban traffic air pollution.

  2. Ethnicity, work-related stress and subjective reports of health by migrant workers: a multi-dimensional model.

    Science.gov (United States)

    Capasso, Roberto; Zurlo, Maria Clelia; Smith, Andrew P

    2018-02-01

    This study integrates different aspects of ethnicity and work-related stress dimensions (based on the Demands-Resources-Individual-Effects model, DRIVE [Mark, G. M., and A. P. Smith. 2008. "Stress Models: A Review and Suggested New Direction." In Occupational Health Psychology, edited by J. Houdmont and S. Leka, 111-144. Nottingham: Nottingham University Press]) and aims to test a multi-dimensional model that combines individual differences, ethnicity dimensions, work characteristics, and perceived job satisfaction/stress as independent variables in the prediction of subjectives reports of health by workers differing in ethnicity. A questionnaire consisting of the following sections was submitted to 900 workers in Southern Italy: for individual and cultural characteristics, coping strategies, personality behaviours, and acculturation strategies; for work characteristics, perceived job demands and job resources/rewards; for appraisals, perceived job stress/satisfaction and racial discrimination; for subjective reports of health, psychological disorders and general health. To test the reliability and construct validity of the extracted factors referred to all dimensions involved in the proposed model and logistic regression analyses to evaluate the main effects of the independent variables on the health outcomes were conducted. Principal component analysis (PCA) yielded seven factors for individual and cultural characteristics (emotional/relational coping, objective coping, Type A behaviour, negative affectivity, social inhibition, affirmation/maintenance culture, and search identity/adoption of the host culture); three factors for work characteristics (work demands, intrinsic/extrinsic rewards, and work resources); three factors for appraisals (perceived job satisfaction, perceived job stress, perceived racial discrimination) and three factors for subjective reports of health (interpersonal disorders, anxious-depressive disorders, and general health). Logistic

  3. [Subjective and objective indicators of job stress and burnout in a residential home for the elderly].

    Science.gov (United States)

    Fiabane, Elena; Dordoni, Paola; Argentero, Piergiorgio

    2016-01-01

    Elderly care workers have a higher risk than other professionals of developing burnout. Despite literature has highlighted the methodological advantage resulting from an integration of subjective and objective measures of stressors, only few studies have investigated job stress and burnout in the Italian elderly care context using this kind of assessment. The aims of this study were: (a) to investigate the level of stress and burnout and their organizational sources in a sample of eldercare workers by means of subjective and objective tools, and b) to compare the stress and burnout levels between health care staff and nursing aides employed in a residential home for the, elderly. The sample of the study included the totality of the elderly workers employed in a residential home for the elderly (N=49; response rate: 100%). The Maslach Burnout Inventory-GS and the Areas of Worklife Scale were used for the subjective assessment of burnout and organizational riskfactors. A check list of objective indicators was used for the objective assessment of job stress. Results from the self-report questionnaires showed high levels of exhaustion and a perception of high workload and unfairness for, the total sample. Objective parameters ofjob stress risk were biomechanical overload, dealing with suffering people and the risk of work-related violence. Nursing aides had greater risk of burnout and reported a greater number of objective sources of stress, compared to health care workers. This exploratory study supports the use of both subjective and objective method for the assessment of job stress risk as the most comprehensive approach for the implementation of preventive and corrective interventions.

  4. Distribution of Side Abutment Stress in Roadway Subjected to Dynamic Pressure and Its Engineering Application

    Directory of Open Access Journals (Sweden)

    Yao Qiangling

    2015-01-01

    Full Text Available The borehole stress-meter was employed in this study to investigate the distribution of the side abutment stress in roadway subjected to dynamic pressure. The results demonstrate that the side abutment stress of the mining roadway reaches a peak value when the distance to the gob is 8 m and the distribution curve of the side abutment stress can be divided into three zones: stress rising zone, stress stabilizing zone, and stress decreasing zone. Further numerical investigation was carried out to study the effect of the coal mass strength, coal seam depth, immediate roof strength, and thickness on the distribution of the side abutment stress. Based on the research results, we determined the reasonable position of the mining roadway and the optimal width of the barrier pillar. The engineering application demonstrates that the retention of the barrier pillar with a width of 5 m along the gob as the haulage roadway for the next panel is feasible, which delivers favorable technological and economic benefits.

  5. A Subject-Specific Kinematic Model to Predict Human Motion in Exoskeleton-Assisted Gait.

    Science.gov (United States)

    Torricelli, Diego; Cortés, Camilo; Lete, Nerea; Bertelsen, Álvaro; Gonzalez-Vargas, Jose E; Del-Ama, Antonio J; Dimbwadyo, Iris; Moreno, Juan C; Florez, Julian; Pons, Jose L

    2018-01-01

    The relative motion between human and exoskeleton is a crucial factor that has remarkable consequences on the efficiency, reliability and safety of human-robot interaction. Unfortunately, its quantitative assessment has been largely overlooked in the literature. Here, we present a methodology that allows predicting the motion of the human joints from the knowledge of the angular motion of the exoskeleton frame. Our method combines a subject-specific skeletal model with a kinematic model of a lower limb exoskeleton (H2, Technaid), imposing specific kinematic constraints between them. To calibrate the model and validate its ability to predict the relative motion in a subject-specific way, we performed experiments on seven healthy subjects during treadmill walking tasks. We demonstrate a prediction accuracy lower than 3.5° globally, and around 1.5° at the hip level, which represent an improvement up to 66% compared to the traditional approach assuming no relative motion between the user and the exoskeleton.

  6. 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

  7. Organ-specific proteomics analysis for identification of response mechanism in soybean seedlings under flooding stress.

    Science.gov (United States)

    Khatoon, Amana; Rehman, Shafiq; Hiraga, Susumu; Makino, Takahiro; Komatsu, Setsuko

    2012-10-22

    Flooding is one of the severe environmental factors which impair growth and yield in soybean plant. To investigate the organ specific response mechanism of soybean under flooding stress, changes in protein species were analyzed using a proteomics approach. Two-day-old soybeans were subjected to flooding for 5 days. Proteins were extracted from root, hypocotyl and leaf, and separated by two-dimensional polyacrylamide gel electrophoresis. In root, hypocotyl and leaf, 51, 66 and 51 protein species were significantly changed, respectively, under flooding stress. In root, metabolism related proteins were increased; however these proteins were decreased in hypocotyl and leaf. In all 3 organs, cytoplasm localized proteins were decreased, and leaf chloroplastic proteins were also decreased. Isoflavone reductase was commonly decreased at protein level in all 3 organs; however, mRNA of isoflavone reductase gene was up-regulated in leaf under flooding stress. Biophoton emission was increased in all 3 organs under flooding stress. The up-regulation of isoflavone reductase gene at transcript level; while decreased abundance at protein level indicated that flooding stress affected the mRNA translation to proteins. These results suggest that concurrence in expression of isoflavone reductase gene at mRNA and protein level along with imbalance in other disease/defense and metabolism related proteins might lead to impaired growth of root, hypocotyl and leaf of soybean seedlings under flooding stress. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Subjective heat stress of urban citizens: influencing factors and coping strategies

    Science.gov (United States)

    Kunz-Plapp, Tina; Hackenbruch, Julia; Schipper, Hans

    2014-05-01

    Given urbanization trend and a higher probability of heat waves in Europe, heat discomfort or heat stress for the population in cities is a growing concern that is addressed from various perspectives, such as urban micro climate, urban and spatial planning, human health, work performance and economic impacts. This presentation focuses on subjective heat stress experienced by urban citizens. In order to better understand individual subjective heat stress of urban citizens and how different measures to cope with heat stress in everyday life are applied, a questionnaire survey was conducted in Karlsruhe, Germany. Karlsruhe is located in one of the warmest regions in Germany and holds the German temperature record of 40.2°C in August 2003. In 2013, two hot weather periods with continuous heat warnings by the German Weather Service for 7 and 8 days occurred during the last 10 days of July and first 10 days of August 2013 with an inofficial maximum temperature of again 40.2°C on July 27th in Karlsruhe (not taken by the official network of the German Weather Service). The survey data was collected in the six weeks after the heat using an online-questionnaire on the website of the South German Climate Office that was announced via newspapers and social media channels to reach a wide audience in Karlsruhe. The questionnaire was additionally sent as paper version to groups of senior citizens to ensure having enough respondents from this heat sensitive social group in the sample. The 428 respondents aged 17-94 show differences in subjective heat stress experienced at home, at work and during various typical activities in daily routine. They differ also in the measures they used to adjust to and cope with the heat such as drinking more, evading the heat, seeking cooler places, changing daily routines, or use of air condition. Differences in heat stress can be explained by housing type, age, subjective health status, employment, and different coping measures and strategies

  9. Laminar shear stress modulates endothelial luminal surface stiffness in a tissue-specific manner.

    Science.gov (United States)

    Merna, Nick; Wong, Andrew K; Barahona, Victor; Llanos, Pierre; Kunar, Balvir; Palikuqi, Brisa; Ginsberg, Michael; Rafii, Shahin; Rabbany, Sina Y

    2018-04-17

    Endothelial cells form vascular beds in all organs and are exposed to a range of mechanical forces that regulate cellular phenotype. We sought to determine the role of endothelial luminal surface stiffness in tissue-specific mechanotransduction of laminar shear stress in microvascular mouse cells and the role of arachidonic acid in mediating this response. Microvascular mouse endothelial cells were subjected to laminar shear stress at 4 dynes/cm 2 for 12 hours in parallel plate flow chambers that enabled real-time optical microscopy and atomic force microscopy measurements of cell stiffness. Lung endothelial cells aligned parallel to flow, while cardiac endothelial cells did not. This rapid alignment was accompanied by increased cell stiffness. The addition of arachidonic acid to cardiac endothelial cells increased alignment and stiffness in response to shear stress. Inhibition of arachidonic acid in lung endothelial cells and embryonic stem cell-derived endothelial cells prevented cellular alignment and decreased cell stiffness. Our findings suggest that increased endothelial luminal surface stiffness in microvascular cells may facilitate mechanotransduction and alignment in response to laminar shear stress. Furthermore, the arachidonic acid pathway may mediate this tissue-specific process. An improved understanding of this response will aid in the treatment of organ-specific vascular disease. © 2018 John Wiley & Sons Ltd.

  10. Alterations in Mitochondrial Oxidative Stress and Mitophagy in Subjects with Prediabetes and Type 2 Diabetes Mellitus

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    Shipra Bhansali

    2017-12-01

    Full Text Available Background and aimHyperglycemia-mediated oxidative stress impedes cell-reparative process like autophagy, which has been implicated in impairment of β-cell function in type 2 diabetes mellitus (T2DM. However, the role of mitophagy (selective mitochondrial autophagy in progression of hyperglycemia remains elusive. This study aimed to assess the impact of increasing severity of hyperglycemia on mitochondrial stress and mitophagy.Design and methodsA case–control study included healthy controls, subjects with prediabetes, newly diagnosed T2DM (NDT2DM and advanced duration of T2DM (ADT2DM (n = 20 each. Mitochondrial stress indices, transcriptional and translational expression of mitophagy markers (PINK1, PARKIN, MFN2, NIX, LC3-II, and LAMP-2 and transmission electron microscopic (TEM studies were performed in peripheral blood mononuclear cells.ResultsWith mild hyperglycemia in subjects with prediabetes, to moderate to severe hyperglycemia in NDT2DM and ADT2DM, a progressive rise in mitochondrial oxidative stress was observed. Prediabetic subjects exhibited significantly increased expression of mitophagy-related markers and showed a positive association with HOMA-β, whereas, patients with NDT2DM and ADT2DM demonstrated decreased expression, with a greater decline in ADT2DM subjects. TEM studies revealed significantly reduced number of distorted mitochondria in prediabetics, as compared to the T2DM patients. In addition, receiver operating characteristic analysis showed HbA1C > 7% (53 mmol/mol was associated with attenuated mitophagy.ConclusionIncreasing hyperglycemia is associated with progressive rise in oxidative stress and altered mitochondrial morphology. Sustenance of mitophagy at HbA1C < 7% (53 mmol/mol strengthens the rationale of achieving HbA1C below this cutoff for good glycemic control. An “adaptive” increase in mitophagy may delay progression to T2DM by preserving the β-cell function in subjects with prediabetes.

  11. Entropy Analysis of RR and QT Interval Variability during Orthostatic and Mental Stress in Healthy Subjects

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    Mathias Baumert

    2014-12-01

    Full Text Available Autonomic activity affects beat-to-beat variability of heart rate and QT interval. The aim of this study was to explore whether entropy measures are suitable to detect changes in neural outflow to the heart elicited by two different stress paradigms. We recorded short-term ECG in 11 normal subjects during an experimental protocol that involved head-up tilt and mental arithmetic stress and computed sample entropy, cross-sample entropy and causal interactions based on conditional entropy from RR and QT interval time series. Head-up tilt resulted in a significant reduction in sample entropy of RR intervals and cross-sample entropy, while mental arithmetic stress resulted in a significant reduction in coupling directed from RR to QT. In conclusion, measures of entropy are suitable to detect changes in neural outflow to the heart and decoupling of repolarisation variability from heart rate variability elicited by orthostatic or mental arithmetic stress.

  12. The Mitochondrial Lon Protease Is Required for Age-Specific and Sex-Specific Adaptation to Oxidative Stress.

    Science.gov (United States)

    Pomatto, Laura C D; Carney, Caroline; Shen, Brenda; Wong, Sarah; Halaszynski, Kelly; Salomon, Matthew P; Davies, Kelvin J A; Tower, John

    2017-01-09

    Multiple human diseases involving chronic oxidative stress show a significant sex bias, including neurodegenerative diseases, cancer, immune dysfunction, diabetes, and cardiovascular disease. However, a possible molecular mechanism for the sex bias in physiological adaptation to oxidative stress remains unclear. Here, we report that Drosophila melanogaster females but not males adapt to hydrogen peroxide stress, whereas males but not females adapt to paraquat (superoxide) stress. Stress adaptation in each sex requires the conserved mitochondrial Lon protease and is associated with sex-specific expression of Lon protein isoforms and proteolytic activity. Adaptation to oxidative stress is lost with age in both sexes. Transgenic expression of transformer gene during development transforms chromosomal males into pseudo-females and confers the female-specific pattern of Lon isoform expression, Lon proteolytic activity induction, and H 2 O 2 stress adaptation; these effects were also observed using adult-specific transformation. Conversely, knockdown of transformer in chromosomal females eliminates the female-specific Lon isoform expression, Lon proteolytic activity induction, and H 2 O 2 stress adaptation and produces the male-specific paraquat (superoxide) stress adaptation. Sex-specific expression of alternative Lon isoforms was also observed in mouse tissues. The results develop Drosophila melanogaster as a model for sex-specific stress adaptation regulated by the Lon protease, with potential implications for understanding sexual dimorphism in human disease. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. The reaction to social stress in social phobia: discordance between physiological and subjective parameters.

    Science.gov (United States)

    Klumbies, Elisabeth; Braeuer, David; Hoyer, Juergen; Kirschbaum, Clemens

    2014-01-01

    Research on the biopsychological background of social phobia (SP) is scarce and inconsistent. We investigated endocrine and autonomic markers along with subjective responses to a standardized stress situation (Trier Social Stress Test, TSST) in SP patients and healthy controls (HC). We examined 88 patients with the primary diagnosis of SP as well as 78 age and sex comparable HCs with the TSST. Blood and saliva samples were obtained before and after the TSST for the assessment of salivary cortisol, plasma cortisol, salivary alpha-amylase (sAA), and prolactin. Heart rate (HR) and heart rate variability (HRV) were recorded continuously. Scalp-near hair samples were collected for the assessment of long-term cortisol secretion. The self-reported stress response was measured with different state and trait scales. While self-reported anxiety was elevated in SP before, during, immediately after, and one week after the TSST, no significant differences in biological stress responses were observed between SP and HC. There was a trend for SP to show higher baseline stress markers. Also long-term cortisol deposition in hair remained unaltered. Our results suggest that the excessive self-reported stress in SP is not reflected by a respective biological stress response. Patients with SP apparently show neither an extreme form of focused fear reactivity nor excessive defensive impairment.

  14. Role of insular cortex in visceral hypersensitivity model in rats subjected to chronic stress.

    Science.gov (United States)

    Yi, LiSha; Sun, HuiHui; Ge, Chao; Chen, Ying; Peng, HaiXia; Jiang, YuanXi; Wu, Ping; Tang, YinHan; Meng, QingWei; Xu, ShuChang

    2014-12-30

    Abnormal processing of visceral sensation at the level of the central nervous system has been proven to be important in the pathophysiologic mechanisms of stress related functional gastrointestinal disorders. However, the specific mechanism is still not clear. The insular cortex (IC) was considered as one important visceral sensory area. Moreover, the IC has been shown to be involved in various neuropsychiatric diseases such as panic disorders and post-traumatic stress disorder. However, whether the IC is important in psychological stress related visceral hypersensitivity has not been studied yet. In our study, through destruction of the bilateral IC, we explored whether the IC played a critical role in the formation of visceral hypersensitivity induced by chronic stress on rats. Chronic partial restraint stress was used to establish viscerally hypersensitive rat model. Bilateral IC lesions were generated by N-methyl-D-day (door) aspartate. After a recovery period of 7 days, 14-day consecutive restraint stress was performed. The visceromotor response to colorectal distension was monitored by recording electromyogram to measure rats׳ visceral sensitivity. We found that bilateral insular cortex lesion could markedly inhibit the formation of visceral hypersensitivity induced by chronic stress. The insular cortex plays a critical role in the pathophysiology of stress-related visceral hypersensitivity.

  15. Modelling and subject-specific validation of the heart-arterial tree system.

    Science.gov (United States)

    Guala, Andrea; Camporeale, Carlo; Tosello, Francesco; Canuto, Claudio; Ridolfi, Luca

    2015-01-01

    A modeling approach integrated with a novel subject-specific characterization is here proposed for the assessment of hemodynamic values of the arterial tree. A 1D model is adopted to characterize large-to-medium arteries, while the left ventricle, aortic valve and distal micro-circulation sectors are described by lumped submodels. A new velocity profile and a new formulation of the non-linear viscoelastic constitutive relation suitable for the {Q, A} modeling are also proposed. The model is firstly verified semi-quantitatively against literature data. A simple but effective procedure for obtaining subject-specific model characterization from non-invasive measurements is then designed. A detailed subject-specific validation against in vivo measurements from a population of six healthy young men is also performed. Several key quantities of heart dynamics-mean ejected flow, ejection fraction, and left-ventricular end-diastolic, end-systolic and stroke volumes-and the pressure waveforms (at the central, radial, brachial, femoral, and posterior tibial sites) are compared with measured data. Mean errors around 5 and 8%, obtained for the heart and arterial quantities, respectively, testify the effectiveness of the model and its subject-specific characterization.

  16. The specifics of the Russian market of confectionery: subject-object certainty

    Directory of Open Access Journals (Sweden)

    Tsarenko Elena

    2012-12-01

    Full Text Available This article describes a study of the Russian confectionery market. Determining the specificity of the market in Russia, identified and examined the components of this market with the help of subject - object orientation. As well as the actuality of considering new approaches to promote sales of confectionery products.

  17. Production and Processing of Subject-Verb Agreement in Monolingual Dutch Children with Specific Language Impairment

    Science.gov (United States)

    Blom, Elma; Vasic, Nada; de Jong, Jan

    2014-01-01

    Purpose: In this study, the authors investigated whether errors with subject-verb agreement in monolingual Dutch children with specific language impairment (SLI) are influenced by verb phonology. In addition, the productive and receptive abilities of Dutch acquiring children with SLI regarding agreement inflection were compared. Method: An SLI…

  18. Sensitivity of subject-specific models to errors in musculo-skeletal geometry

    NARCIS (Netherlands)

    Carbone, V.; van der Krogt, M.M.; Koopman, H.F.J.M.; Verdonschot, N.

    2012-01-01

    Subject-specific musculo-skeletal models of the lower extremity are an important tool for investigating various biomechanical problems, for instance the results of surgery such as joint replacements and tendon transfers. The aim of this study was to assess the potential effects of errors in

  19. Objective and subjective measurement of sleep disturbance in female trauma survivors with posttraumatic stress disorder.

    Science.gov (United States)

    Werner, Kimberly B; Griffin, Michael G; Galovski, Tara E

    2016-06-30

    Sleep disturbance may be the most often endorsed symptom of posttraumatic stress disorder (PTSD). Much of this research is based on subjective reports from trauma survivors; however, objective measures of sleep-related impairment have yielded findings inconsistent with self-report data. More studies investigating subjective and objective assessments concordantly are needed to understand sleep impairment in PTSD. The current study examined PTSD-related sleep disturbance in a female interpersonal violence cohort with full PTSD diagnoses (N=51) assessing subjective (global and daily diary measures) and objective (actigraphy) sleep measures concurrently. PTSD severity was positively associated with global, subjective reports of sleep impairment and insomnia. Subjective measures of sleep (including global sleep impairment, insomnia, and daily sleep diary reports of total sleep time, sleep efficiency, and sleep onset latency) were moderately to strongly correlated. However, no significant correlations between subjective and objective reports of sleep impairment were found in this cohort. Analyses demonstrated an overall elevation in subjectively reported sleep impairment when compared to objective measurement assessed concurrently. Findings demonstrate a lack of agreement between subjective and objective measurements of sleep in a PTSD-positive female cohort, suggesting objective and subjective sleep impairments are distinct sleep parameters that do not necessarily directly co-vary. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  20. [Correlation between specific and nonspecific posttraumatic stress disorder symptoms with healthcare consumption among 340 French soldiers].

    Science.gov (United States)

    Holterbach, L; Baumann, C; Andreani, B; Desré, D; Auxéméry, Y

    2015-10-01

    The psychotraumatic disorders are often difficult to diagnose because the specific symptoms of posttraumatic stress disorder (revival, hyperarousal, avoidance) are rarely a direct demand for health care: for reasons determined by the psychopathological structure of trauma, its symptomatology and course, the psychotraumatised subjects seek a care system for nonspecific psychological or somatoform symptoms: depressive episode, cognitive disorders, other anxiety disorders, histrionic and obsessive symptoms, changes in personality, pain disorders and somatization. Somatic pain may also result from a war injury and psychosomatic complications, addictive or consequences of risk behaviours during the evolution of posttraumatic stress disorder. To establish a correlation between the PCLS and the evaluation of the healthcare consumption in a military population. We conducted a multicenter epidemiological study analyzing the PCLS and a questionnaire assessing health care consumption. The PCLS has been studied in various forms: quantitative (17 to 85), in qualitative classes (disorders, could be developed a score of health care consumption which would include the number of days of sick leave and unavailability, the number and quality of medical consultations, the number and quality of drug and laboratory requirements, the number of hospitalisations. To the identification of posttraumatic stress disorder, the PCLS score as well as the consumer healthcare score are valuable tools but do not replace the subjectivity of the clinical relationship: return to this shared subjectivity with the practitioner remains a diagnostic dimension, but also therapeutic, fundamental. Copyright © 2015 L’Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.

  1. Expression of NCED gene in colored cotton genotypes subjected to water stress

    Directory of Open Access Journals (Sweden)

    Alexandre M. S. de Souza

    Full Text Available ABSTRACT Considering that the NCED gene acts on the biosynthetic cascade of ABA, a hormone involved in the functioning of stomata and consequently in the regulation of transpiration, the aim of this research was to analyze the expression of this gene in colored cotton genotypes subjected to water stress at the beginning of plant growth. Four colored cotton genotypes were used, subjected to two managements, with and without water stress, beginning the treatments when the blade of the first true leaves reached an area that allowed the evaluation of gas exchange. For the studies of the expression of the NCED gene, via RT-qPCR, leaves were collected on three distinct dates: at 4 and 6 days of water stress, and after the plants regained their turgor. The differential expression of NCED was found in all genotypes, with higher levels of expression related to six days of water stress. When the stomatal conductance was around 25%, there was overexpression in the genotype CNPA 2009.13, followed by CNPA 2009.6, BRS SAFIRA and CNPA 2009.11, confirming the data obtained in the semi-quantitative RT-PCR. The NCED gene is involved in the response to water stress in the vegetative phase of colored cotton.

  2. Emotional intelligence, life satisfaction and subjective happiness in female student health professionals: the mediating effect of perceived stress.

    Science.gov (United States)

    Ruiz-Aranda, D; Extremera, N; Pineda-Galán, C

    2014-03-01

    The objective of the present study was to extend previous findings by examining the relationship between emotional intelligence (EI) and well-being indicators (life satisfaction and happiness) in a 12-week follow-up study. In addition, we examined the influence of perceived stress on the relationship between EI and well-being. Female students from the School of Health Sciences (n = 264) completed an ability measure of emotional intelligence. After 12 weeks, participants completed the Perceived Stress Scale, Satisfaction with Life Scale and Subjective Happiness Scale. Participants with higher EI reported less perceived stress and higher levels of life satisfaction and happiness. The results of this study suggest that perceived stress mediates the relationship between EI and well-being indicators, specifically life satisfaction and happiness. These findings suggest an underlying process by which high emotional intelligence may increase well-being in female students in nursing and allied health sciences by reducing the experience of stress. The implications of these findings for future research and for working with health professions to improve well-being outcomes are discussed. © 2013 John Wiley & Sons Ltd.

  3. Subject-specific knee joint geometry improves predictions of medial tibiofemoral contact forces

    Science.gov (United States)

    Gerus, Pauline; Sartori, Massimo; Besier, Thor F.; Fregly, Benjamin J.; Delp, Scott L.; Banks, Scott A.; Pandy, Marcus G.; D’Lima, Darryl D.; Lloyd, David G.

    2013-01-01

    Estimating tibiofemoral joint contact forces is important for understanding the initiation and progression of knee osteoarthritis. However, tibiofemoral contact force predictions are influenced by many factors including muscle forces and anatomical representations of the knee joint. This study aimed to investigate the influence of subject-specific geometry and knee joint kinematics on the prediction of tibiofemoral contact forces using a calibrated EMG-driven neuromusculoskeletal model of the knee. One participant fitted with an instrumented total knee replacement walked at a self-selected speed while medial and lateral tibiofemoral contact forces, ground reaction forces, whole-body kinematics, and lower-limb muscle activity were simultaneously measured. The combination of generic and subject-specific knee joint geometry and kinematics resulted in four different OpenSim models used to estimate muscle-tendon lengths and moment arms. The subject-specific geometric model was created from CT scans and the subject-specific knee joint kinematics representing the translation of the tibia relative to the femur was obtained from fluoroscopy. The EMG-driven model was calibrated using one walking trial, but with three different cost functions that tracked the knee flexion/extension moments with and without constraint over the estimated joint contact forces. The calibrated models then predicted the medial and lateral tibiofemoral contact forces for five other different walking trials. The use of subject-specific models with minimization of the peak tibiofemoral contact forces improved the accuracy of medial contact forces by 47% and lateral contact forces by 7%, respectively compared with the use of generic musculoskeletal model. PMID:24074941

  4. Subjective health complaints, work-related stress and self-efficacy in Norwegian aircrew.

    Science.gov (United States)

    Omholt, M L; Tveito, T H; Ihlebæk, C

    2017-03-01

    The European civilian aviation industry has undergone major changes in the last decade. Despite this, there is little knowledge about work-related stress and subjective health complaints (SHCs) affecting Norwegian aircrew. To investigate the relationships between work-related stress, self-efficacy and SHCs in commercial aircrew in Norway and to explore differences between cockpit and cabin crew. Aircrew members from the three major airlines operating from Norway completed an electronically distributed questionnaire. Linear regression analyses were used to investigate the association between work-related stress, self-efficacy and SHCs. There was a 21% response rate. Among the 843 study subjects, tiredness, sleep problems, bloating, low back pain, headaches and neck pain were the most prevalent SHCs. Cabin crew reported significantly higher numbers, prevalences and mean values for all SHCs compared with cockpit crew (P stress levels. High levels of work-related stress were significantly associated with all SHC factors in both groups. Self-efficacy partly moderated the relationship between stress and psychological complaints in both cockpit and cabin crew, and for musculoskeletal complaints in cockpit crew. The model explained 23 and 32% of the variance in psychological complaints for cockpit and cabin crew, respectively. Commercial aircrew in Norway reported high numbers of SHCs, and high levels of work-related stress were associated with high numbers of SHC. More knowledge is needed on the physical, organizational and psychosocial stressors affecting cockpit and cabin crew in order to create a healthier work environment for these groups. © The Author 2016. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  5. Aerobic exercise modulation of mental stress-induced responses in cultured endothelial progenitor cells from healthy and metabolic syndrome subjects.

    Science.gov (United States)

    Rocha, Natalia G; Sales, Allan R K; Miranda, Renan L; Silva, Mayra S; Silva, Jemima F R; Silva, Bruno M; Santos, Aline A; Nóbrega, Antonio C L

    2015-02-15

    Numerous studies have demonstrated that exercise acutely prevents the reduction in flow-mediated dilation induced by mental stress in subjects with metabolic syndrome (MetS). However, it is unknown whether a similar effect occurs in endothelial progenitors cells (EPCs). This study investigated whether exercise protects from the deleterious effect of mental stress on cultured EPCs in healthy subjects and those with MetS. Ten healthy subjects (aged 31±2) and ten subjects with MetS (aged 36±2) were enrolled. Subjects underwent a mental stress test, followed immediately by either 40 min of leg cycling or rest across two randomized sessions: mental stress+non-exercise control (MS) and mental stress+exercise (MS+EXE). The Stroop Color-Word Test was used to elicit mental stress. Blood samples were drawn at baseline and following sessions to isolate mononuclear cells. These cells were cultured in fibronectin-coated plates for seven days, and EPCs were identified by immunofluorescence (acLDL(+)/ UEA-I Lectin(+)). All subjects presented similar increases in mean blood pressure and heart rate during the mental stress test (P0.05). The EPC response to MS and MS+EXE was increased in healthy subjects, whereas it was decreased in subjects with MetS (Pexercise session increased EPCs in healthy subjects but did not prevent the EPC reduction induced by mental stress among subjects with MetS. © 2015.

  6. Predicting changes in posttraumatic growth and subjective well-being among breast cancer survivors: the role of social support and stress.

    Science.gov (United States)

    McDonough, Meghan H; Sabiston, Catherine M; Wrosch, Carsten

    2014-01-01

    Social support is theoretically expected to be positively associated with posttraumatic growth (PTG) and subjective well-being, and stress is expected to be positively associated with PTG and negatively associated with subjective well-being among breast cancer (BC) survivors. However, empirical evidence is mixed, predominantly cross-sectional, and few studies have examined the unique effects of these predictors on positive changes in psychological experiences post cancer diagnosis and systemic treatment. This study examined both general and BC-specific social support and stress as predictors of change in PTG and subjective well-being among BC survivors. Women (N = 173, Mage  = 55.40, SD = 10.99) who had recently finished treatment completed demographic and treatment measures at baseline (T1); general and cancer-specific social support and stress, PTG and subjective well-being at 3 months (T2); and PTG and subjective well-being again at 6 months (T3). Longitudinal predictors of change in PTG and subjective well-being were examined using hierarchical multiple regression. The BC-specific social support (β = .12) and stress (cancer worry; β = .10) predicted increasing levels of PTG. Improvements in subjective well-being were predicted by higher levels of general social support (β = .21) and lower levels of general stress (β = -.59). There are distinct predictors of change in PTG and subjective well-being among BC survivors, supporting the distinction between the trauma-specific process of PTG and well-being. Copyright © 2013 John Wiley & Sons, Ltd.

  7. Relationship between job stress and subjective oral health symptoms in male financial workers in Japan.

    Science.gov (United States)

    Yoshino, Koichi; Suzuki, Seitaro; Ishizuka, Yoichi; Takayanagi, Atsushi; Sugihara, Naoki; Kamijyo, Hideyuki

    2017-04-07

    The aim was to assess subjective oral health symptoms and job stress, as measured by self-assessment of how demanding the job is, in male financial workers. The participants were recruited by applying screening procedures to a pool of Japanese registrants in an online database. For the stress check, 7 items about how demanding the job is were selected from The Brief Job Stress Questionnaire (BJSQ). Participants comprised a total of 950 financial male workers, ages 25 to 64. Participants who answered "I can't complete my work in the required time" had more decayed teeth (p=0.010). Participants who felt that their job is highly demanding (answered affirmatively to 6 or all 7 items) were more likely to report "often get food stuck between teeth" (p=0.030), "there are some foods I can't eat" (p=0.005), "bad breath" (p=0.032), and "jaw makes clicking sound" (p=0.032). The independent variable of total stress score of 24-28 was found to be correlated to at least three oral health symptoms (OR: 3.25; 95%CI: 1.66-6.35). These results indicate that certain job stress factors are associated with certain oral health symptoms, and that oral health symptoms are likely predictors of job stress.

  8. Presence of a dog reduces subjective but not physiological stress responses to an analog trauma.

    Science.gov (United States)

    Lass-Hennemann, Johanna; Peyk, Peter; Streb, Markus; Holz, Elena; Michael, Tanja

    2014-01-01

    Dogs are known to have stress and anxiety reducing effects. Several studies have shown that dogs are able to calm people during cognitive and performance stressors. Recently, therapy dogs have been proposed as a treatment adjunct for post-traumatic stress disorder patients. In this study we aimed to investigate, whether dogs also have anxiety- and stress reducing effect during "traumatic stressors." 80 healthy female participants were randomly assigned to one of four conditions. They were exposed to a "traumatic" film clip (trauma-film-paradigm). For one group of participants a friendly dog was present during the film, one group of participants was accompanied by a friendly human, another control group watched the film with a toy animal and the last group watched the film clip alone. Participants that were accompanied by the dog during the film reported lower anxiety ratings and less negative affect after the film clip as compared to the "toy dog group" and the "alone group." Results of the "dog group" were comparable to the group that was accompanied by a friendly human. There were no differences in physiological stress responses between the four conditions. Our results show that dogs are able to lessen subjectively experienced stress and anxiety during a "traumatic" stress situation. This effect was comparable to that of social support by a friendly person. Implications for PTSD patients are discussed.

  9. Automatic generation of a subject-specific model for accurate markerless motion capture and biomechanical applications.

    Science.gov (United States)

    Corazza, Stefano; Gambaretto, Emiliano; Mündermann, Lars; Andriacchi, Thomas P

    2010-04-01

    A novel approach for the automatic generation of a subject-specific model consisting of morphological and joint location information is described. The aim is to address the need for efficient and accurate model generation for markerless motion capture (MMC) and biomechanical studies. The algorithm applied and expanded on previous work on human shapes space by embedding location information for ten joint centers in a subject-specific free-form surface. The optimal locations of joint centers in the 3-D mesh were learned through linear regression over a set of nine subjects whose joint centers were known. The model was shown to be sufficiently accurate for both kinematic (joint centers) and morphological (shape of the body) information to allow accurate tracking with MMC systems. The automatic model generation algorithm was applied to 3-D meshes of different quality and resolution such as laser scans and visual hulls. The complete method was tested using nine subjects of different gender, body mass index (BMI), age, and ethnicity. Experimental training error and cross-validation errors were 19 and 25 mm, respectively, on average over the joints of the ten subjects analyzed in the study.

  10. Effects of instructions and cue subjectiveness on specificity of autobiographical memory recall

    Directory of Open Access Journals (Sweden)

    Jorge J. Ricarte-Trives

    2014-10-01

    Full Text Available The first aim of this study was to determine the power of instructions on the specificity of autobiographical memory as obtained with the Autobiographical Memory Test (AMT; Williams & Broadbent, 1986 and the efficacy of cue word criteria selection based on subjective parameters obtained with a standardized lexical program. Results showed a high power of specific instructions in its written version in contrast to non-directed memory recall to the same list of words three weeks later in a counterbalanced repeated measures within-subjects design. This effect was stronger when subjects previously were faced to the non-specific recovery task. Matched word lists using the "Buscapalabras" program (Davis & Perea, 2005 showed a very similar behaviour. These results point out that the same stimuli can be used repeatedly to obtain voluntary and involuntary retrieval with changes at instructional level. Additionally, standardized lexical programs can be employed to adapt cue-words of memory recall systems controlling for subjective differences related to language parameters (frequency, imageability and familiarity.

  11. Instantaneous Metabolic Cost of Walking: Joint-Space Dynamic Model with Subject-Specific Heat Rate.

    Directory of Open Access Journals (Sweden)

    Dustyn Roberts

    Full Text Available A subject-specific model of instantaneous cost of transport (ICOT is introduced from the joint-space formulation of metabolic energy expenditure using the laws of thermodynamics and the principles of multibody system dynamics. Work and heat are formulated in generalized coordinates as functions of joint kinematic and dynamic variables. Generalized heat rates mapped from muscle energetics are estimated from experimental walking metabolic data for the whole body, including upper-body and bilateral data synchronization. Identified subject-specific energetic parameters-mass, height, (estimated maximum oxygen uptake, and (estimated maximum joint torques-are incorporated into the heat rate, as opposed to the traditional in vitro and subject-invariant muscle parameters. The total model metabolic energy expenditure values are within 5.7 ± 4.6% error of the measured values with strong (R2 > 0.90 inter- and intra-subject correlations. The model reliably predicts the characteristic convexity and magnitudes (0.326-0.348 of the experimental total COT (0.311-0.358 across different subjects and speeds. The ICOT as a function of time provides insights into gait energetic causes and effects (e.g., normalized comparison and sensitivity with respect to walking speed and phase-specific COT, which are unavailable from conventional metabolic measurements or muscle models. Using the joint-space variables from commonly measured or simulated data, the models enable real-time and phase-specific evaluations of transient or non-periodic general tasks that use a range of (aerobic energy pathway similar to that of steady-state walking.

  12. Region-specific vulnerability to endoplasmic reticulum stress ...

    Indian Academy of Sciences (India)

    2013-11-06

    Nov 6, 2013 ... glucose-regulated protein (GRP) 78, a good marker of ER stress, were assessed by Western ..... calcium homeostasis is disturbed, because ATP is needed to ... lum stress and insulin signalling proteins in diabetes-induced.

  13. Real-time simulation of thermal stresses and creep in plates subjected to transient heat input

    DEFF Research Database (Denmark)

    Hattel, Jesper Henri; Jacobsen, Torben Krogsdal; Hansen, P.N.

    1997-01-01

    -difference approach. It applies a general formulation which takes into account nonconstant material properties (e.g. temperature, material, or time dependency), heat-transfer coefficients, and creep. The temperature calculation applies a one-dimensional numerical model, whereas the stress analysis is semi......This paper presents a novel numerical technique for solving the temperature and stress fields in a plate subjected to arbitrarily varying transient boundary conditions (transient temperature and heat-flux variations) on a surface. The numerical method is based on the control-volume finite......-two-dimensional. Both plane stress and plane strain conditions are considered as extreme cases. It is shown that, by using the developed numerical technique, very fast real-time simulations can be performed. The method has proved its applicability in e.g. high-pressure die-casting, and applications to this industrial...

  14. Disaggregating Within- and Between-Person Effects of Social Identification on Subjective and Endocrinological Stress Reactions in a Real-Life Stress Situation.

    Science.gov (United States)

    Ketturat, Charlene; Frisch, Johanna U; Ullrich, Johannes; Häusser, Jan A; van Dick, Rolf; Mojzisch, Andreas

    2016-02-01

    Several experimental and cross-sectional studies have established the stress-buffering effect of social identification, yet few longitudinal studies have been conducted within this area of research. This study is the first to make use of a multilevel approach to disaggregate between- and within-person effects of social identification on subjective and endocrinological stress reactions. Specifically, we conducted a study with 85 prospective students during their 1-day aptitude test for a university sports program. Ad hoc groups were formed, in which students completed several tests in various disciplines together. At four points in time, salivary cortisol, subjective strain, and identification with their group were measured. Results of multilevel analyses show a significant within-person effect of social identification: The more students identified with their group, the less stress they experienced and the lower their cortisol response was. Between-person effects were not significant. Advantages of using multilevel approaches within this field of research are discussed. © 2015 by the Society for Personality and Social Psychology, Inc.

  15. Diversity of Survival Patterns among Escherichia coli O157:H7 Genotypes Subjected to Food-Related Stress Conditions.

    Science.gov (United States)

    Elhadidy, Mohamed; Álvarez-Ordóñez, Avelino

    2016-01-01

    The purpose of this study was to evaluate the resistance patterns to food-related stresses of Shiga toxin producing Escherichia coli O157:H7 strains belonging to specific genotypes. A total of 33 E. coli O157:H7 strains were exposed to seven different stress conditions acting as potential selective pressures affecting the transmission of E. coli O157:H7 to humans through the food chain. These stress conditions included cold, oxidative, osmotic, acid, heat, freeze-thaw, and starvation stresses. The genotypes used for comparison included lineage-specific polymorphism, Shiga-toxin-encoding bacteriophage insertion sites, clade type, tir (A255T) polymorphism, Shiga toxin 2 subtype, and antiterminator Q gene allele. Bacterial resistance to different stressors was calculated by determining D-values (times required for inactivation of 90% of the bacterial population), which were then subjected to univariate and multivariate analyses. In addition, a relative stress resistance value, integrating resistance values to all tested stressors, was calculated for each bacterial strain and allowed for a ranking-type classification of E. coli O157:H7 strains according to their environmental robustness. Lineage I/II strains were found to be significantly more resistant to acid, cold, and starvation stress than lineage II strains. Similarly, tir (255T) and clade 8 encoding strains were significantly more resistant to acid, heat, cold, and starvation stress than tir (255A) and non-clade 8 strains. Principal component analysis, which allows grouping of strains with similar stress survival characteristics, separated strains of lineage I and I/II from strains of lineage II, which in general showed reduced survival abilities. Results obtained suggest that lineage I/II, tir (255T), and clade 8 strains, which have been previously reported to be more frequently associated with human disease cases, have greater multiple stress resistance than strains of other genotypes. The results from this

  16. Specific terms glossary for subjects taught in Physical Culture first year career

    Directory of Open Access Journals (Sweden)

    Ana Isel Rodríguez Cruz

    2016-08-01

    Full Text Available Contents comprehension is an important element in the learning process; present didactic ways demand from teaching styles that favor communicative competence in the students. Taking into account the relevance of this topic in the teaching learning process it was decided to develop the present work, which has the objective to offer the students a tool that allow them an efficient comprehension of the contents they receive in the Physical Culture first year career subjects. To fulfil the goal a glossary with specific terms of basketball, chess, swimming, athletics, basic gymnastics, and morphology was designed starting from the results of the initial diagnosis, the scientific observation, as well as the detail revision of the normative documents that rule Communicative Spanish subject. The glossary use favor the students´ texts comprehension development from the mentioned subject.

  17. Cytomegalovirus (CMV) Epitope-Specific CD4+ T Cells Are Inflated in HIV+ CMV+ Subjects.

    Science.gov (United States)

    Abana, Chike O; Pilkinton, Mark A; Gaudieri, Silvana; Chopra, Abha; McDonnell, Wyatt J; Wanjalla, Celestine; Barnett, Louise; Gangula, Rama; Hager, Cindy; Jung, Dae K; Engelhardt, Brian G; Jagasia, Madan H; Klenerman, Paul; Phillips, Elizabeth J; Koelle, David M; Kalams, Spyros A; Mallal, Simon A

    2017-11-01

    Select CMV epitopes drive life-long CD8 + T cell memory inflation, but the extent of CD4 memory inflation is poorly studied. CD4 + T cells specific for human CMV (HCMV) are elevated in HIV + HCMV + subjects. To determine whether HCMV epitope-specific CD4 + T cell memory inflation occurs during HIV infection, we used HLA-DR7 (DRB1*07:01) tetramers loaded with the glycoprotein B DYSNTHSTRYV (DYS) epitope to characterize circulating CD4 + T cells in coinfected HLA-DR7 + long-term nonprogressor HIV subjects with undetectable HCMV plasma viremia. DYS-specific CD4 + T cells were inflated among these HIV + subjects compared with those from an HIV - HCMV + HLA-DR7 + cohort or with HLA-DR7-restricted CD4 + T cells from the HIV-coinfected cohort that were specific for epitopes of HCMV phosphoprotein-65, tetanus toxoid precursor, EBV nuclear Ag 2, or HIV gag protein. Inflated DYS-specific CD4 + T cells consisted of effector memory or effector memory-RA + subsets with restricted TCRβ usage and nearly monoclonal CDR3 containing novel conserved amino acids. Expression of this near-monoclonal TCR in a Jurkat cell-transfection system validated fine DYS specificity. Inflated cells were polyfunctional, not senescent, and displayed high ex vivo levels of granzyme B, CX 3 CR1, CD38, or HLA-DR but less often coexpressed CD38 + and HLA-DR + The inflation mechanism did not involve apoptosis suppression, increased proliferation, or HIV gag cross-reactivity. Instead, the findings suggest that intermittent or chronic expression of epitopes, such as DYS, drive inflation of activated CD4 + T cells that home to endothelial cells and have the potential to mediate cytotoxicity and vascular disease. Copyright © 2017 by The American Association of Immunologists, Inc.

  18. Genotype-specific responses to light stress in eelgrass Zostera marina, a marine foundation plant

    DEFF Research Database (Denmark)

    Salo, Tiina Elina; Reusch, Thorsten B. H.

    2015-01-01

    , and their performance during light limitation and 4 wk of recovery was compared to non-shaded controls. In addition to growth and biomass, we investigated storage carbohydrates and quantified the expression of genes involved in carbohydrate metabolism, photosynthesis and control of oxidative stress. Plants showed......Within mono-specific meadows of clonal plants, genotypic diversity may functionally replace species diversity. Little is known about the variability in performance and plasticity of different genotypes towards anthropogenically induced stressors. In this field experiment we compared light......-limitation stress responses and recovery of different eelgrass Zostera marina genotypes to assess the variability in phenotypic plasticity and gene expression between different genotypes. Replicated monoculture plots of 4 genotypes were subjected to a simulated turbidity period of 4 wk using shading screens...

  19. Presence of a dog reduces subjective but not physiological stress responses to an analogue trauma

    Directory of Open Access Journals (Sweden)

    Johanna eLass-Hennemann

    2014-09-01

    Full Text Available Dogs are known to have stress and anxiety reducing effects. Several studies have shown that dogs are able to calm people during cognitive and performance stressors. Recently, therapy dogs have been proposed as a treatment adjunct for PTSD patients. In this study we aimed to investigate, whether dogs also have anxiety- and stress reducing effect during traumatic stressors. 80 healthy female participants were randomly assigned to one of 4 conditions. They were exposed to a traumatic film clip (trauma-film-paradigm. For one group of participants a friendly dog was present during the film, one group of participants was accompanied by a friendly human, another control group watched the film with a toy animal and the last group watched the film clip alone. Participants that were accompanied by the dog during the film reported lower anxiety ratings and less negative affect after the film clip as compared to the toy dog group and the alone group. Results of the dog group were comparable to the group that was accompanied by a friendly human. There were no differences in physiological stress responses between the four conditions. Our results show that dogs are able to lessen subjectively experienced stress and anxiety during a traumatic stress situation. This effect was comparable to that of social support by a friendly person. Implications for PTSD patients are discussed.

  20. Effect of a stress management program on subjects with neck pain: A pilot randomized controlled trial.

    Science.gov (United States)

    Metikaridis, T Damianos; Hadjipavlou, Alexander; Artemiadis, Artemios; Chrousos, George; Darviri, Christina

    2016-05-20

    Studies have shown that stress is implicated in the cause of neck pain (NP). The purpose of this study is to examine the effect of a simple, zero cost stress management program on patients suffering from NP. This study is a parallel-type randomized clinical study. People suffering from chronic non-specific NP were chosen randomly to participate in an eight week duration program of stress management (N= 28) (including diaphragmatic breathing, progressive muscle relaxation) or in a no intervention control condition (N= 25). Self-report measures were used for the evaluation of various variables at the beginning and at the end of the eight-week monitoring period. Descriptive and inferential statistic methods were used for the statistical analysis. At the end of the monitoring period, the intervention group showed a statistically significant reduction of stress and anxiety (p= 0.03, p= 0.01), report of stress related symptoms (p= 0.003), percentage of disability due to NP (p= 0.000) and NP intensity (p= 0.002). At the same time, daily routine satisfaction levels were elevated (p= 0.019). No statistically significant difference was observed in cortisol measurements. Stress management has positive effects on NP patients.

  1. A Subject-Specific Kinematic Model to Predict Human Motion in Exoskeleton-Assisted Gait

    Science.gov (United States)

    Torricelli, Diego; Cortés, Camilo; Lete, Nerea; Bertelsen, Álvaro; Gonzalez-Vargas, Jose E.; del-Ama, Antonio J.; Dimbwadyo, Iris; Moreno, Juan C.; Florez, Julian; Pons, Jose L.

    2018-01-01

    The relative motion between human and exoskeleton is a crucial factor that has remarkable consequences on the efficiency, reliability and safety of human-robot interaction. Unfortunately, its quantitative assessment has been largely overlooked in the literature. Here, we present a methodology that allows predicting the motion of the human joints from the knowledge of the angular motion of the exoskeleton frame. Our method combines a subject-specific skeletal model with a kinematic model of a lower limb exoskeleton (H2, Technaid), imposing specific kinematic constraints between them. To calibrate the model and validate its ability to predict the relative motion in a subject-specific way, we performed experiments on seven healthy subjects during treadmill walking tasks. We demonstrate a prediction accuracy lower than 3.5° globally, and around 1.5° at the hip level, which represent an improvement up to 66% compared to the traditional approach assuming no relative motion between the user and the exoskeleton. PMID:29755336

  2. A Combined Experimental and Computational Approach to Subject-Specific Analysis of Knee Joint Laxity

    Science.gov (United States)

    Harris, Michael D.; Cyr, Adam J.; Ali, Azhar A.; Fitzpatrick, Clare K.; Rullkoetter, Paul J.; Maletsky, Lorin P.; Shelburne, Kevin B.

    2016-01-01

    Modeling complex knee biomechanics is a continual challenge, which has resulted in many models of varying levels of quality, complexity, and validation. Beyond modeling healthy knees, accurately mimicking pathologic knee mechanics, such as after cruciate rupture or meniscectomy, is difficult. Experimental tests of knee laxity can provide important information about ligament engagement and overall contributions to knee stability for development of subject-specific models to accurately simulate knee motion and loading. Our objective was to provide combined experimental tests and finite-element (FE) models of natural knee laxity that are subject-specific, have one-to-one experiment to model calibration, simulate ligament engagement in agreement with literature, and are adaptable for a variety of biomechanical investigations (e.g., cartilage contact, ligament strain, in vivo kinematics). Calibration involved perturbing ligament stiffness, initial ligament strain, and attachment location until model-predicted kinematics and ligament engagement matched experimental reports. Errors between model-predicted and experimental kinematics averaged ligaments agreed with literature descriptions. These results demonstrate the ability of our constraint models to be customized for multiple individuals and simultaneously call attention to the need to verify that ligament engagement is in good general agreement with literature. To facilitate further investigations of subject-specific or population based knee joint biomechanics, data collected during the experimental and modeling phases of this study are available for download by the research community. PMID:27306137

  3. Oxidative stress specifically downregulates survivin to promote breast tumour formation.

    Science.gov (United States)

    Pervin, S; Tran, L; Urman, R; Braga, M; Parveen, M; Li, S A; Chaudhuri, G; Singh, R

    2013-03-05

    Breast cancer, a heterogeneous disease has been broadly classified into oestrogen receptor positive (ER+) or oestrogen receptor negative (ER-) tumour types. Each of these tumours is dependent on specific signalling pathways for their progression. While high levels of survivin, an anti-apoptotic protein, increases aggressive behaviour in ER- breast tumours, oxidative stress (OS) promotes the progression of ER+ breast tumours. Mechanisms and molecular targets by which OS promotes tumourigenesis remain poorly understood. DETA-NONOate, a nitric oxide (NO)-donor induces OS in breast cancer cell lines by early re-localisation and downregulation of cellular survivin. Using in vivo models of HMLE(HRAS) xenografts and E2-induced breast tumours in ACI rats, we demonstrate that high OS downregulates survivin during initiation of tumourigenesis. Overexpression of survivin in HMLE(HRAS) cells led to a significant delay in tumour initiation and tumour volume in nude mice. This inverse relationship between survivin and OS was also observed in ER+ human breast tumours. We also demonstrate an upregulation of NADPH oxidase-1 (NOX1) and its activating protein p67, which are novel markers of OS in E2-induced tumours in ACI rats and as well as in ER+ human breast tumours. Our data, therefore, suggest that downregulation of survivin could be an important early event by which OS initiates breast tumour formation.

  4. Subject-Specific Sparse Dictionary Learning for Atlas-Based Brain MRI Segmentation.

    Science.gov (United States)

    Roy, Snehashis; He, Qing; Sweeney, Elizabeth; Carass, Aaron; Reich, Daniel S; Prince, Jerry L; Pham, Dzung L

    2015-09-01

    Quantitative measurements from segmentations of human brain magnetic resonance (MR) images provide important biomarkers for normal aging and disease progression. In this paper, we propose a patch-based tissue classification method from MR images that uses a sparse dictionary learning approach and atlas priors. Training data for the method consists of an atlas MR image, prior information maps depicting where different tissues are expected to be located, and a hard segmentation. Unlike most atlas-based classification methods that require deformable registration of the atlas priors to the subject, only affine registration is required between the subject and training atlas. A subject-specific patch dictionary is created by learning relevant patches from the atlas. Then the subject patches are modeled as sparse combinations of learned atlas patches leading to tissue memberships at each voxel. The combination of prior information in an example-based framework enables us to distinguish tissues having similar intensities but different spatial locations. We demonstrate the efficacy of the approach on the application of whole-brain tissue segmentation in subjects with healthy anatomy and normal pressure hydrocephalus, as well as lesion segmentation in multiple sclerosis patients. For each application, quantitative comparisons are made against publicly available state-of-the art approaches.

  5. Behaviour of a pre-stressed concrete pressure-vessel subjected to a high temperature gradient

    International Nuclear Information System (INIS)

    Dubois, F.

    1965-01-01

    After a review of the problems presented by pressure-vessels for atomic reactors (shape of the vessel, pressures, openings, foundations, etc.) the advantages of pre-stressed concrete vessels with respect to steel ones are given. The use of pre-stressed concrete vessels however presents many difficulties connected with the properties of concrete. Thus, because of the absence of an exact knowledge of the material, it is necessary to place a sealed layer of steel against the concrete, to have a thermal insulator or a cooling circuit for limiting the deformations and stresses, etc. It follows that the study of the behaviour of pre-stressed concrete and of the vessel subjected- to a high temperature gradient can yield useful information. A one-tenth scale model of a pre-stressed concrete cylindrical vessel without any side openings and without a base has been built. Before giving a description of the tests the authors consider some theoretical aspects concerning 'scale model-actual structure' similitude conditions and the calculation of the thermal and mechanical effects. The pre-stressed concrete model was heated internally by a 'pyrotenax' element and cooled externally by a very strong air current. The concrete was pre-stressed using horizontal and vertical cables held at 80 kg/cm 2 ; the thermal gradient was 160 deg. C. During the various tests, measurements were made of the overall and local deformations, the changes in water content, the elasticity modulus, the stress and creep of the cables and the depths of the cracks. The overall deformations observed are in line with thermal deformation theories and the creep of the cables attained 20 to 30 per cent according to their position relative to the internal surface. The dynamic elasticity modulus decreased by half but the concrete keeps its good mechanical properties. Finally, cracks 8 to 12 cm deep and 2 to 3 mms wide appeared in that part of the concrete which was not pre-stressed. The results obtained make it

  6. Gender differences in subjective health complaints in adolescence: The roles of self-esteem, stress from schoolwork and body dissatisfaction.

    Science.gov (United States)

    Aanesen, Fiona; Meland, Eivind; Torp, Steffen

    2017-06-01

    The aims of this study were to examine subjective health complaints among Norwegian adolescents and assess the development of gender differences in subjective health complaints between age 14 and 16; to investigate whether self-esteem, stress from schoolwork or body dissatisfaction affected adolescents' subjective health complaints; and determine whether these factors could explain the excess of subjective health complaints among girls. We used multiple linear regression analyses to analyse longitudinal survey data from 751 Norwegian adolescents at the ages of 14 and 16. The results from various cross-sectional and prospective analyses were compared. Girls reported more subjective health complaints than boys, and gender differences increased from age 14 to 16. Self-esteem and stress from schoolwork had cross-sectional and prospective associations with subjective health complaints. Stress from schoolwork at age 14 was also associated with changes in subjective health complaints from age 14 to 16. The cross-sectional mediation analyses indicated that self-esteem and stress from schoolwork accounted for 61% of the excess of subjective health complaints among girls at age 16. The same variables measured at age 14 accounted for 24% of the gender differences in subjective health complaints two years later. The investigated factors could not account for the increase in gender differences in subjective health complaints between ages 14 and 16. The findings showed that self-esteem and stress from schoolwork were associated with subjective health complaints during adolescence. These factors could partially explain the excess of subjective health complaints among girls.

  7. Brain aromatase and circulating corticosterone are rapidly regulated by combined acute stress and sexual interaction in a sex specific manner

    Science.gov (United States)

    Dickens, M.J.; Balthazart, J.; Cornil, C. A.

    2012-01-01

    Neural production of 17β-oestradiol via aromatisation of testosterone may play a critical role in rapid, non-genomic regulation of physiological and behavioural processes. In brain nuclei implicated in the control of sexual behaviour, sexual or stressfull stimuli induce respectively a rapid inhibition or increase in preoptic aromatase activity (AA). Here, we tested quail that were either non-stressed or acutely stressed (15 min restraint) immediately prior to sexual interaction (5 min) with stressed or non-stressed partners. We measured nuclei-specific AA changes, corresponding behavioural output, fertilisation rates and corticosterone (CORT) concentrations. In males, sexual interaction rapidly reversed stress-induced increases of AA in the medial preoptic nucleus (POM). This time scale (behaviour suggesting that the input from the sexual stimuli on POM AA may actively preserve sexual behaviour despite stress exposure. We also found distinct sex differences in contextual physiological responses: while males did not show any effect of partner status, females responded to both their stress exposure and the male partner’s stress exposure at the level of circulating CORT and AA. In addition, fertilisation rates and female CORT correlated with the male partner’s exhibition of sexually aggressive behaviour suggesting that female perception of the male can affect their physiology as much as direct stress. Overall, male reproduction appears relatively simple – sexual stimuli, irrespective of stress, drives major neural changes including rapid reversal of stress-induced changes of AA. In contrast, female reproduction appears more nuanced and context specific, with subjects responding physiologically and behaviourally to stress, the male partner’s stress exposure, and female-directed male behaviour. PMID:22612582

  8. An open-label trial of L-5-hydroxytryptophan in subjects with romantic stress.

    Science.gov (United States)

    Emanuele, Enzo; Bertona, Marco; Minoretti, Piercarlo; Geroldi, Diego

    2010-01-01

    This open-label trial assessed the clinical efficacy of L-5-hydroxytryptophan (5-HTP), a natural serotonin precursor, in nondepressed young subjects with high levels of romantic stress. Since both neurotrophins and serotonin have been linked to human romantic attachment, we sought to investigate the changes in serum brain-derived neurotrophic factor (BDNF) levels and platelet serotonin content in relation to the changes in romantic stress throughout the study. A total of 15 healthy subjects (11 females and 4 males, mean age: 23.3 ± 2.1 years) who experienced a recent romantic break-up or reported recent romantic problems took part in the study. The participants were treated openly for 6 weeks with L-5-hydroxytryptophan (60 mg Griffonia simplicifolia extract containing 12.8 mg 5-HTP b.i.d., Amorex, Coropharm, Villach, Austria). The subjects were evaluated at baseline, at 3 weeks and at the end of the 6-week trial using an adapted version of the Seiffge-Krenke's Problem Questionnaire. BDNF and platelet serotonin content were determined at baseline, at 3 weeks, and after the completion of the 6-week trial. We observed significant improvements in romantic stress scores from weeks 0 through 3 (p=0.007) but no further significant improvement was evident from weeks 3 through 6 (p=0.19). At 6 weeks, subjects had a significant increase from baseline in both BDNF and platelet serotonin values. Our data suggest that direct modulation of the serotonergic system may have use for the treatment of psychological suffering associated with unreciprocated romantic love.

  9. Oxidative stress and inflammation in lean and obese subjects with polycystic ovary syndrome.

    Science.gov (United States)

    Blair, Sarah A; Kyaw-Tun, Tommy; Young, Ian S; Phelan, Niamh A; Gibney, James; McEneny, Jane

    2013-01-01

    To determine whether polycystic ovary syndrome (PCOS) independently influences oxidative stress and inflammation or if the culprit is the comorbidities of obesity and/or insulin resistance common to this condition. Thirty women with PCOS were matched for age, body mass index and insulin resistance with 30 control subjects. Oxidative stress was examined by measuring the total oxidant status (TOS) and total antioxidant capacity (TAC) by spectrophotometric assay. The inflammatory biomarkers, C-reactive protein, plasminogen activator inhibitor-1, myeloperoxidase, neopterin, and serum amyloid A were measured by ELISA methodologies. Oxidative status was increased in the PCOS subjects relative to their weight-matched controls (TOS: obese PCOS patients vs. obese controls, 42.42 +/- 4.49 vs. 32.57 +/- 1.97, plean PCOS patients vs. lean controls, 33.69 +/- 1.59 vs. 28.69 +/- 1.18 micromol H2O2 Equiv/L, p lean PCOS group relative to their weight-matched controls (TAC: lean PCOS patients vs. lean controls, 1.10 +/- 0.09 vs. 1.49 +/- 0.03 nmol Trolox Equiv/L, p PCOS independently influenced oxidative stress. Overall, the presence of PCOS may increase cardiovascular risk.

  10. Stress: Specific Life Events in the Teaching Profession.

    Science.gov (United States)

    Martray, Carl R.; Adams, Ronald D.

    This study examined the greatest stressors in teaching situations that affect teachers, and how these events vary for groups of elementary, middle, and secondary school teachers. The list of possibly stressful situations was taken from the Teaching Events Stress Inventory (TESI), developed by Cichon and Koff in 1978. Data were collected from…

  11. Feedlot cattle susceptibility to heat stress: an animal specific model

    Science.gov (United States)

    The extreme effects of heat stress in a feedlot situation can cause losses exceeding 5% of all the cattle on feed in a single feedlot. These losses can be very devastating to a localized area of feedlot producers. Animal stress is a result of the combination of three different components: environm...

  12. Critical shear stress for erosion of cohesive soils subjected to temperatures typical of wildfires

    Science.gov (United States)

    Moody, J.A.; Dungan, Smith J.; Ragan, B.W.

    2005-01-01

    [1] Increased erosion is a well-known response after wildfire. To predict and to model erosion on a landscape scale requires knowledge of the critical shear stress for the initiation of motion of soil particles. As this soil property is temperature-dependent, a quantitative relation between critical shear stress and the temperatures to which the soils have been subjected during a wildfire is required. In this study the critical shear stress was measured in a recirculating flume using samples of forest soil exposed to different temperatures (40??-550??C) for 1 hour. Results were obtained for four replicates of soils derived from three different types of parent material (granitic bedrock, sandstone, and volcanic tuffs). In general, the relation between critical shear stress and temperature can be separated into three different temperature ranges (275??C), which are similar to those for water repellency and temperature. The critical shear stress was most variable (1.0-2.0 N m-2) for temperatures 2.0 N m-2) between 175?? and 275??C, and was essentially constant (0.5-0.8 N m-2) for temperatures >275??C. The changes in critical shear stress with temperature were found to be essentially independent of soil type and suggest that erosion processes in burned watersheds can be modeled more simply than erosion processes in unburned watersheds. Wildfire reduces the spatial variability of soil erodibility associated with unburned watersheds by eliminating the complex effects of vegetation in protecting soils and by reducing the range of cohesion associated with different types of unburned soils. Our results indicate that modeling the erosional response after a wildfire depends primarily on determining the spatial distribution of the maximum soil temperatures that were reached during the wildfire. Copyright 2005 by the American Geophysical Union.

  13. Specific and unspecific responses of plants to cold and drought stress

    Indian Academy of Sciences (India)

    Madhu Sudhan

    2007-03-22

    Mar 22, 2007 ... Introduction. Cold, drought and salinity are those environmental stressors which affect .... The general stress concept emphasizing the incidence of a specific primary and a less specific secondary strain by a specific stressor.

  14. Exogenous melatonin improves corn (Zea mays L.) embryo proteome in seeds subjected to chilling stress.

    Science.gov (United States)

    Kołodziejczyk, Izabela; Dzitko, Katarzyna; Szewczyk, Rafał; Posmyk, Małgorzata M

    2016-04-01

    Melatonin (MEL; N-acetyl-5-methoxytryptamine) plays an important role in plant stress defense. Various plant species rich in this indoleamine have shown a higher capacity for stress tolerance. Moreover, it has great potential for plant biostimulation, is biodegradable and non-toxic for the environment. All this indicates that our concept of seed enrichment with exogenous MEL is justified. This work concerns the effects of corn (Zea mays L.) seed pre-sowing treatments supplemented with MEL. Non-treated seeds (nt), and those hydroprimed with water (H) or with MEL solutions 50 and 500 μM (HMel50, HMel500) were compared. Positive effects of seed priming are particularly apparent during germination under suboptimal conditions. The impact of MEL applied by priming on seed protein profiles during imbibition/germination at low temperature has not been investigated to date. In order to identify changes in the corn seed proteome after applying hydropriming techniques, purified protein extracts of chilling stressed seed embryos (14 days, 5°C) were separated by two-dimensional electrophoresis. Then proteome maps were graphically and statistically compared and selected protein spots were qualitatively analyzed using mass spectrometry techniques and identified. This study aimed to analyze the priming-induced changes in maize embryo proteome and at identifying priming-associated and MEL-associated proteins in maize seeds subjected to chilling. We attempt to explain how MEL expands plant capacity for stress tolerance. Copyright © 2016 Elsevier GmbH. All rights reserved.

  15. Sex-specific association between functional neuropeptide S receptor gene (NPSR1) variants and cortisol and central stress responses.

    Science.gov (United States)

    Streit, Fabian; Akdeniz, Ceren; Haddad, Leila; Kumsta, Robert; Entringer, Sonja; Frank, Josef; Yim, Ilona S; Zänkert, Sandra; Witt, Stephanie H; Kirsch, Peter; Rietschel, Marcella; Wüst, Stefan

    2017-02-01

    The brain neuropeptide S (NPS) system has recently generated substantial interest and may be of major relevance for central stress regulation. The NPS receptor (NPSR1) is highly expressed in the limbic system, exogenous NPS exerts pronounced anxiolytic and fear-attenuating effects in rodents and extensive close crosstalk between the NPS system and the hypothalamic-pituitary-adrenal (HPA) axis has been demonstrated. In humans, associations between NPSR1 variants and anxiety and panic disorder, as well as amygdala responsiveness to fear- relevant faces and prefrontal cortex activity in a fear conditioning paradigm have been reported. Moreover, a NPSR1 sequence variant was found to be associated with cortisol stress responses in males. Here, we performed a haplotype-based analysis covering three functional NPSR1 single nucleotide polymorphisms in the promoter (rs2530547), in exon 3 (rs324981) and exon 6 (rs727162) in 277 healthy subjects who were exposed to the Trier Social Stress Test (TSST). A significant sex-specific association with salivary cortisol responses to acute psychosocial stress was detected for the common TTC haplotype 2 (frequency of about 20%). In an additional study using an imaging genetics approach, 65 healthy subjects were exposed to a stress paradigm for scanner environments (“ScanSTRESS”). We found a significant and, again, sex-specific interaction between rs324981 (whose minor T-allele is harbored by haplotype 2) and the neural stress response in a cluster close to the parahippocampal gyrus (whole brain corrected). Moreover, as in the TSST sample, NPSR1 variation was associated with salivary cortisol responses (on a trend level) in a sex-specific way. In summary, our preliminary findings in two independent cohorts exposed to different stress paradigms suggest that the NPS system significantly influences acute stress responses and that sequence variation in NPSR1 may contribute to sex differences in stress regulation. Copyright © 2016

  16. [Subjective illness beliefs of Turkish migrants with mental disorders--specific characteristics compared to german patients].

    Science.gov (United States)

    Franz, Michael; Lujić, Claudia; Koch, Eckhardt; Wüsten, Bernd; Yürük, Nergüz; Gallhofer, Bernd

    2007-10-01

    Knowledge about culture- and migration-specific characteristics of subjective illness beliefs in Turkish patients is necessary for adequate treatment. Analysis of subjective illness beliefs in Turkish patients (F3; F4; n = 79) in comparison to matched Germans (n = 79) using a modified version of the Illness Perception Questionnaire IPQ-R. Differences were explored by t-tests and chi(2)-tests. Turkish patients believed significantly stronger in a chronical timeline of illness and in negative illness consequences, while German patients believed significantly stronger in treatment control and personal control. Turkish patients more often mentioned external causes of their disease compared to Germans. The results provide explanations of the deficient health care situation for Turkish migrants in Germany.

  17. Specifics of Educational Texts Selection for Schoolchildren Doing the Humanities Subjects

    Directory of Open Access Journals (Sweden)

    T. V. Oblasova

    2012-01-01

    Full Text Available The paper proposes the new approach to educational text selection for the humanities teaching. Its specifics is based on the wide interpretation of educational texts, as the culture texts involved in cognitive learning activity and fulfilling the multiple tasks of the related subjects and personal development. The educational text is taken as a generalized model, its content and structure determining the scheme of a speech cognitive activity, as well as the meaning formation mechanism responsible for understanding and personal development. The texts and tasks selection is oriented on schoolchildren’s understanding with the reference to the psycholinguistic, psychological and hermeneutic approaches; information extraction and interpretation level related to the author’s and student’s context. The given approach could provide the basis for developing and structuring the textbooks content for the humanities subjects

  18. Sensitivity analysis of a validated subject-specific finite element model of the human craniofacial skeleton.

    Science.gov (United States)

    Szwedowski, T D; Fialkov, J; Whyne, C M

    2011-01-01

    Developing a more complete understanding of the mechanical response of the craniofacial skeleton (CFS) to physiological loads is fundamental to improving treatment for traumatic injuries, reconstruction due to neoplasia, and deformities. Characterization of the biomechanics of the CFS is challenging due to its highly complex structure and heterogeneity, motivating the utilization of experimentally validated computational models. As such, the objective of this study was to develop, experimentally validate, and parametrically analyse a patient-specific finite element (FE) model of the CFS to elucidate a better understanding of the factors that are of intrinsic importance to the skeletal structural behaviour of the human CFS. An FE model of a cadaveric craniofacial skeleton was created from subject-specific computed tomography data. The model was validated based on bone strain measurements taken under simulated physiological-like loading through the masseter and temporalis muscles (which are responsible for the majority of craniofacial physiologic loading due to mastication). The baseline subject-specific model using locally defined cortical bone thicknesses produced the strongest correlation to the experimental data (r2 = 0.73). Large effects on strain patterns arising from small parametric changes in cortical thickness suggest that the very thin bony structures present in the CFS are crucial to characterizing the local load distribution in the CFS accurately.

  19. The FachRef-Assistant: Personalised, subject specific, and transparent stock management

    Directory of Open Access Journals (Sweden)

    Eike T. Spielberg

    2017-07-01

    Full Text Available We present in this paper a personalized web application for the weeding of printed resources: the FachRef-Assistant. It offers an extensive range of tools for evidence based stock management, based on the thorough analysis of usage statistics. Special attention is paid to the criteria individualization, transparency of the parameters used, and generic functions. Currently, it is designed to work with the Aleph-System from ExLibris, but efforts were spent to keep the application as generic as possible. For example, all procedures specific to the local library system have been collected in one Java package. The inclusion of library specific properties such as collections and systematics has been designed to be highly generic as well by mapping the individual entries onto an in-memory database. Hence simple adaption of the package and the mappings would render the FachRef-Assistant compatible to other library systems. The personalization of the application allows for the inclusion of subject specific usage properties as well as of variations between different collections within one subject area. The parameter sets used to analyse the stock and to prepare weeding and purchase proposal lists are included in the output XML-files to facilitate a high degree of transparency, objectivity and reproducibility.

  20. Prediction of thermal and mechanical stress-strain responses of TMC's subjected to complex TMF histories

    Science.gov (United States)

    Johnson, W. S.; Mirdamadi, M.

    1994-01-01

    This paper presents an experimental and analytical evaluation of cross-plied laminates of Ti-15V-3Cr-3Al-3Sn (Ti-15-3) matrix reinforced with continuous silicon-carbide fibers (SCS-6) subjected to a complex TMF loading profile. Thermomechanical fatigue test techniques were developed to conduct a simulation of a generic hypersonic flight profile. A micromechanical analysis was used. The analysis predicts the stress-strain response of the laminate and of the constituents in each ply during thermal and mechanical cycling by using only constituent properties as input. The fiber was modeled as elastic with transverse orthotropic and temperature-dependent properties. The matrix was modeled using a thermoviscoplastic constitutive relation. The fiber transverse modulus was reduced in the analysis to simulate the fiber-matrix interface failures. Excellent correlation was found between measured and predicted laminate stress-strain response due to generic hypersonic flight profile when fiber debonding was modeled.

  1. Predictive maintenance policy for a gradually deteriorating system subject to stress

    Energy Technology Data Exchange (ETDEWEB)

    Deloux, E. [IRCCyN/Ecole des Mines de Nantes, Nantes (France); Castanier, B. [IRCCyN/Ecole des Mines de Nantes, Nantes (France)], E-mail: bruno.castanier@emn.fr; Berenguer, C. [Universite de Technologie de Troyes/CNRS, Troyes (France)

    2009-02-15

    This paper deals with a predictive maintenance policy for a continuously deteriorating system subject to stress. We consider a system with two failure mechanisms which are, respectively, due to an excessive deterioration level and a shock. To optimize the maintenance policy of the system, an approach combining statistical process control (SPC) and condition-based maintenance (CBM) is proposed. CBM policy is used to inspect and replace the system according to the observed deterioration level. SPC is used to monitor the stress covariate. In order to assess the performance of the proposed maintenance policy and to minimize the long-run expected maintenance cost per unit of time, a mathematical model for the maintained system cost is derived. Analysis based on numerical results are conducted to highlight the properties of the proposed maintenance policy in respect to the different maintenance parameters.

  2. Analysis of stresses on buried pipeline subjected to landslide based on numerical simulation and regression analysis

    Energy Technology Data Exchange (ETDEWEB)

    Han, Bing; Jing, Hongyuan; Liu, Jianping; Wu, Zhangzhong [PetroChina Pipeline RandD Center, Langfang, Hebei (China); Hao, Jianbin [School of Petroleum Engineering, Southwest Petroleum University, Chengdu, Sichuan (China)

    2010-07-01

    Landslides have a serious impact on the integrity of oil and gas pipelines in the tough terrain of Western China. This paper introduces a solving method of axial stress, which uses numerical simulation and regression analysis for the pipelines subjected to landslides. Numerical simulation is performed to analyze the change regularity of pipe stresses for the five vulnerability assessment indexes, which are: the distance between pipeline and landslide tail; the thickness of landslide; the inclination angle of landslide; the pipeline length passing through landslide; and the buried depth of pipeline. A pipeline passing through a certain landslide in southwest China was selected as an example to verify the feasibility and effectiveness of this method. This method has practical applicability, but it would need large numbers of examples to better verify its reliability and should be modified accordingly. Also, it only considers the case where the direction of the pipeline is perpendicular to the primary slip direction of the landslide.

  3. Predictive maintenance policy for a gradually deteriorating system subject to stress

    International Nuclear Information System (INIS)

    Deloux, E.; Castanier, B.; Berenguer, C.

    2009-01-01

    This paper deals with a predictive maintenance policy for a continuously deteriorating system subject to stress. We consider a system with two failure mechanisms which are, respectively, due to an excessive deterioration level and a shock. To optimize the maintenance policy of the system, an approach combining statistical process control (SPC) and condition-based maintenance (CBM) is proposed. CBM policy is used to inspect and replace the system according to the observed deterioration level. SPC is used to monitor the stress covariate. In order to assess the performance of the proposed maintenance policy and to minimize the long-run expected maintenance cost per unit of time, a mathematical model for the maintained system cost is derived. Analysis based on numerical results are conducted to highlight the properties of the proposed maintenance policy in respect to the different maintenance parameters

  4. Effect of mental stress on plasma homovanillic acid in healthy human subjects.

    Science.gov (United States)

    Sumiyoshi, T; Yotsutsuji, T; Kurachi, M; Itoh, H; Kurokawa, K; Saitoh, O

    1998-07-01

    Plasma levels of homovanillic acid (pHVA) have been suggested to provide a measure of dopaminergic activity in the central nervous system. The present study investigated the effect of mental stress by the Kraepelin test, a test of continuous arithmetic addition of single-digit figures for 30 min, on pHVA levels in 13 male psychiatrically normal healthy volunteers. Following an overnight fast and restricted physical activity, plasma samples were collected immediately before and after the administration of the Kraepelin test. Plasma HVA levels following the administration of the Kraepelin test were significantly lower than the pretest pHVA levels. The percent change in pHVA levels by the Kraepelin test positively correlated with pretest pHVA levels. The observed reduction in pHVA levels by mental stress in normal subjects may reflect some aspects of a dopamine-dependent restitutive system in the brain.

  5. Visual cue-specific craving is diminished in stressed smokers.

    Science.gov (United States)

    Cochran, Justinn R; Consedine, Nathan S; Lee, John M J; Pandit, Chinmay; Sollers, John J; Kydd, Robert R

    2017-09-01

    Craving among smokers is increased by stress and exposure to smoking-related visual cues. However, few experimental studies have tested both elicitors concurrently and considered how exposures may interact to influence craving. The current study examined craving in response to stress and visual cue exposure, separately and in succession, in order to better understand the relationship between craving elicitation and the elicitor. Thirty-nine smokers (21 males) who forwent smoking for 30 minutes were randomized to complete a stress task and a visual cue task in counterbalanced orders (creating the experimental groups); for the cue task, counterbalanced blocks of neutral, motivational control, and smoking images were presented. Self-reported craving was assessed after each block of visual stimuli and stress task, and after a recovery period following each task. As expected, the stress and smoking images generated greater craving than neutral or motivational control images (p smokers are stressed, visual cues have little additive effect on craving, and different types of visual cues elicit comparable craving. These findings may imply that once stressed, smokers will crave cigarettes comparably notwithstanding whether they are exposed to smoking image cues.

  6. Testosterone potentiates the hypoxic ventilatory response of adult male rats subjected to neonatal stress.

    Science.gov (United States)

    Fournier, Sébastien; Gulemetova, Roumiana; Joseph, Vincent; Kinkead, Richard

    2014-05-01

    Neonatal stress disrupts development of homeostatic systems. During adulthood, male rats subjected to neonatal maternal separation (NMS) are hypertensive and show a larger hypoxic ventilatory response (HVR), with greater respiratory instability during sleep. Neonatal stress also affects sex hormone secretion; hypoxia increases circulating testosterone of NMS (but not control) male rats. Given that these effects of NMS are not observed in females, we tested the hypothesis that testosterone elevation is necessary for the stress-related increase of the HVR in adult male rats. Pups subjected to NMS were placed in an incubator for 3 h per day from postnatal day 3 to 12. Control pups remained undisturbed. Rats were reared until adulthood, and the HVR was measured by plethysmography (fractional inspired O2 = 0.12, for 20 min). We used gonadectomy to evaluate the effects of reducing testosterone on the HVR. Gonadectomy had no effect on the HVR of control animals but reduced that of NMS animals below control levels. Immunohistochemistry was used to quantify androgen receptors in brainstem areas involved in the HVR. Androgen receptor expression was generally greater in NMS rats than in control rats; the most significant increase was noted in the caudal region of the nucleus tractus solitarii. We conclude that the abnormal regulation of testosterone is important in stress-related augmentation of the HVR. The greater number of androgen receptors within the brainstem may explain why NMS rats are more sensitive to testosterone withdrawal. Based on the similarities of the cardiorespiratory phenotype of NMS rats and patients suffering from sleep-disordered breathing, these results provide new insight into its pathophysiology, especially sex-based differences in its prevalence. © 2014 The Authors. Experimental Physiology © 2014 The Physiological Society.

  7. Subject-specific pedagogical content knowledge: Implications for alternatively and traditionally trained biology teachers

    Science.gov (United States)

    Ravgiala, Rebekah Rae

    Theories regarding the development of expertise hold implications for alternative and traditional certification programs and the teachers they train. The literature suggests that when compared to experts in the field of teaching, the behaviors of novices differ in ways that are directly attributed to their pedagogical content knowledge. However, few studies have examined how first and second year biology teachers entering the profession from traditional and alternative training differ in their demonstration of subject-specific pedagogical content knowledge. The research problem in this multicase, naturalistic inquiry investigated how subject-specific pedagogical content knowledge was manifested among first and second year biology teachers in the task of transforming subject matter into forms that are potentially meaningful to students when explicit formal training has been and has not been imparted to them as preservice teachers. Two first year and two second year biology teachers were the subjects of this investigation. Allen and Amber obtained their certification through an alternative summer training institute in consecutive years. Tiffany and Tricia obtained their certification through a traditional, graduate level training program in consecutive years. Both programs were offered at the same northeastern state university. Participants contributed to six data gathering techniques including an initial semi-structured interview, responses to the Conceptions of Teaching Science questionnaire (Hewson & Hewson, 1989), three videotaped biology lessons, evaluation of three corresponding lesson plans, and a final semi-structured interview conducted at the end of the investigation. An informal, end-of-study survey intended to offer participants an opportunity to disclose their thoughts and needs as first year teachers was also employed. Results indicate that while conceptions of teaching science may vary slightly among participants, there is no evidence to suggest that

  8. Medical Image Processing for Fully Integrated Subject Specific Whole Brain Mesh Generation

    Directory of Open Access Journals (Sweden)

    Chih-Yang Hsu

    2015-05-01

    Full Text Available Currently, anatomically consistent segmentation of vascular trees acquired with magnetic resonance imaging requires the use of multiple image processing steps, which, in turn, depend on manual intervention. In effect, segmentation of vascular trees from medical images is time consuming and error prone due to the tortuous geometry and weak signal in small blood vessels. To overcome errors and accelerate the image processing time, we introduce an automatic image processing pipeline for constructing subject specific computational meshes for entire cerebral vasculature, including segmentation of ancillary structures; the grey and white matter, cerebrospinal fluid space, skull, and scalp. To demonstrate the validity of the new pipeline, we segmented the entire intracranial compartment with special attention of the angioarchitecture from magnetic resonance imaging acquired for two healthy volunteers. The raw images were processed through our pipeline for automatic segmentation and mesh generation. Due to partial volume effect and finite resolution, the computational meshes intersect with each other at respective interfaces. To eliminate anatomically inconsistent overlap, we utilized morphological operations to separate the structures with a physiologically sound gap spaces. The resulting meshes exhibit anatomically correct spatial extent and relative positions without intersections. For validation, we computed critical biometrics of the angioarchitecture, the cortical surfaces, ventricular system, and cerebrospinal fluid (CSF spaces and compared against literature values. Volumina and surface areas of the computational mesh were found to be in physiological ranges. In conclusion, we present an automatic image processing pipeline to automate the segmentation of the main intracranial compartments including a subject-specific vascular trees. These computational meshes can be used in 3D immersive visualization for diagnosis, surgery planning with haptics

  9. Sensitivity of subject-specific models to errors in musculo-skeletal geometry.

    Science.gov (United States)

    Carbone, V; van der Krogt, M M; Koopman, H F J M; Verdonschot, N

    2012-09-21

    Subject-specific musculo-skeletal models of the lower extremity are an important tool for investigating various biomechanical problems, for instance the results of surgery such as joint replacements and tendon transfers. The aim of this study was to assess the potential effects of errors in musculo-skeletal geometry on subject-specific model results. We performed an extensive sensitivity analysis to quantify the effect of the perturbation of origin, insertion and via points of each of the 56 musculo-tendon parts contained in the model. We used two metrics, namely a Local Sensitivity Index (LSI) and an Overall Sensitivity Index (OSI), to distinguish the effect of the perturbation on the predicted force produced by only the perturbed musculo-tendon parts and by all the remaining musculo-tendon parts, respectively, during a simulated gait cycle. Results indicated that, for each musculo-tendon part, only two points show a significant sensitivity: its origin, or pseudo-origin, point and its insertion, or pseudo-insertion, point. The most sensitive points belong to those musculo-tendon parts that act as prime movers in the walking movement (insertion point of the Achilles Tendon: LSI=15.56%, OSI=7.17%; origin points of the Rectus Femoris: LSI=13.89%, OSI=2.44%) and as hip stabilizers (insertion points of the Gluteus Medius Anterior: LSI=17.92%, OSI=2.79%; insertion point of the Gluteus Minimus: LSI=21.71%, OSI=2.41%). The proposed priority list provides quantitative information to improve the predictive accuracy of subject-specific musculo-skeletal models. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Are subject-specific musculoskeletal models robust to the uncertainties in parameter identification?

    Directory of Open Access Journals (Sweden)

    Giordano Valente

    Full Text Available Subject-specific musculoskeletal modeling can be applied to study musculoskeletal disorders, allowing inclusion of personalized anatomy and properties. Independent of the tools used for model creation, there are unavoidable uncertainties associated with parameter identification, whose effect on model predictions is still not fully understood. The aim of the present study was to analyze the sensitivity of subject-specific model predictions (i.e., joint angles, joint moments, muscle and joint contact forces during walking to the uncertainties in the identification of body landmark positions, maximum muscle tension and musculotendon geometry. To this aim, we created an MRI-based musculoskeletal model of the lower limbs, defined as a 7-segment, 10-degree-of-freedom articulated linkage, actuated by 84 musculotendon units. We then performed a Monte-Carlo probabilistic analysis perturbing model parameters according to their uncertainty, and solving a typical inverse dynamics and static optimization problem using 500 models that included the different sets of perturbed variable values. Model creation and gait simulations were performed by using freely available software that we developed to standardize the process of model creation, integrate with OpenSim and create probabilistic simulations of movement. The uncertainties in input variables had a moderate effect on model predictions, as muscle and joint contact forces showed maximum standard deviation of 0.3 times body-weight and maximum range of 2.1 times body-weight. In addition, the output variables significantly correlated with few input variables (up to 7 out of 312 across the gait cycle, including the geometry definition of larger muscles and the maximum muscle tension in limited gait portions. Although we found subject-specific models not markedly sensitive to parameter identification, researchers should be aware of the model precision in relation to the intended application. In fact, force

  11. nmsBuilder: Freeware to create subject-specific musculoskeletal models for OpenSim.

    Science.gov (United States)

    Valente, Giordano; Crimi, Gianluigi; Vanella, Nicola; Schileo, Enrico; Taddei, Fulvia

    2017-12-01

    Musculoskeletal modeling and simulations of movement have been increasingly used in orthopedic and neurological scenarios, with increased attention to subject-specific applications. In general, musculoskeletal modeling applications have been facilitated by the development of dedicated software tools; however, subject-specific studies have been limited also by time-consuming modeling workflows and high skilled expertise required. In addition, no reference tools exist to standardize the process of musculoskeletal model creation and make it more efficient. Here we present a freely available software application, nmsBuilder 2.0, to create musculoskeletal models in the file format of OpenSim, a widely-used open-source platform for musculoskeletal modeling and simulation. nmsBuilder 2.0 is the result of a major refactoring of a previous implementation that moved a first step toward an efficient workflow for subject-specific model creation. nmsBuilder includes a graphical user interface that provides access to all functionalities, based on a framework for computer-aided medicine written in C++. The operations implemented can be used in a workflow to create OpenSim musculoskeletal models from 3D surfaces. A first step includes data processing to create supporting objects necessary to create models, e.g. surfaces, anatomical landmarks, reference systems; and a second step includes the creation of OpenSim objects, e.g. bodies, joints, muscles, and the corresponding model. We present a case study using nmsBuilder 2.0: the creation of an MRI-based musculoskeletal model of the lower limb. The model included four rigid bodies, five degrees of freedom and 43 musculotendon actuators, and was created from 3D surfaces of the segmented images of a healthy subject through the modeling workflow implemented in the software application. We have presented nmsBuilder 2.0 for the creation of musculoskeletal OpenSim models from image-based data, and made it freely available via nmsbuilder

  12. Specific Antibodies Reacting with SV40 Large T Antigen Mimotopes in Serum Samples of Healthy Subjects.

    Directory of Open Access Journals (Sweden)

    Mauro Tognon

    Full Text Available Simian Virus 40, experimentally assayed in vitro in different animal and human cells and in vivo in rodents, was classified as a small DNA tumor virus. In previous studies, many groups identified Simian Virus 40 sequences in healthy individuals and cancer patients using PCR techniques, whereas others failed to detect the viral sequences in human specimens. These conflicting results prompted us to develop a novel indirect ELISA with synthetic peptides, mimicking Simian Virus 40 capsid viral protein antigens, named mimotopes. This immunologic assay allowed us to investigate the presence of serum antibodies against Simian Virus 40 and to verify whether Simian Virus 40 is circulating in humans. In this investigation two mimotopes from Simian Virus 40 large T antigen, the viral replication protein and oncoprotein, were employed to analyze for specific reactions to human sera antibodies. This indirect ELISA with synthetic peptides from Simian Virus 40 large T antigen was used to assay a new collection of serum samples from healthy subjects. This novel assay revealed that serum antibodies against Simian Virus 40 large T antigen mimotopes are detectable, at low titer, in healthy subjects aged from 18-65 years old. The overall prevalence of reactivity with the two Simian Virus 40 large T antigen peptides was 20%. This new ELISA with two mimotopes of the early viral regions is able to detect in a specific manner Simian Virus 40 large T antigen-antibody responses.

  13. Aging causes decreased resistance to multiple stresses and a failure to activate specific stress response pathways

    Science.gov (United States)

    Bergsma, Alexis L.; Senchuk, Megan M.; Van Raamsdonk, Jeremy M.

    2016-01-01

    In this work, we examine the relationship between stress resistance and aging. We find that resistance to multiple types of stress peaks during early adulthood and then declines with age. To dissect the underlying mechanisms, we use C. elegans transcriptional reporter strains that measure the activation of different stress responses including: the heat shock response, mitochondrial unfolded protein response, endoplasmic reticulum unfolded protein response, hypoxia response, SKN-1-mediated oxidative stress response, and the DAF-16-mediated stress response. We find that the decline in stress resistance with age is at least partially due to a decreased ability to activate protective mechanisms in response to stress. In contrast, we find that any baseline increase in stress caused by the advancing age is too mild to detectably upregulate any of the stress response pathways. Further exploration of how worms respond to stress with increasing age revealed that the ability to mount a hormetic response to heat stress is also lost with increasing age. Overall, this work demonstrates that resistance to all types of stress declines with age. Based on our data, we speculate that the decrease in stress resistance with advancing age results from a genetically-programmed inactivation of stress response pathways, not accumulation of damage. PMID:27053445

  14. Aging causes decreased resistance to multiple stresses and a failure to activate specific stress response pathways.

    Science.gov (United States)

    Dues, Dylan J; Andrews, Emily K; Schaar, Claire E; Bergsma, Alexis L; Senchuk, Megan M; Van Raamsdonk, Jeremy M

    2016-04-01

    In this work, we examine the relationship between stress resistance and aging. We find that resistance to multiple types of stress peaks during early adulthood and then declines with age. To dissect the underlying mechanisms, we use C. elegans transcriptional reporter strains that measure the activation of different stress responses including: the heat shock response, mitochondrial unfolded protein response, endoplasmic reticulum unfolded protein response, hypoxia response, SKN-1-mediated oxidative stress response, and the DAF-16-mediated stress response. We find that the decline in stress resistance with age is at least partially due to a decreased ability to activate protective mechanisms in response to stress. In contrast, we find that any baseline increase in stress caused by the advancing age is too mild to detectably upregulate any of the stress response pathways. Further exploration of how worms respond to stress with increasing age revealed that the ability to mount a hormetic response to heat stress is also lost with increasing age. Overall, this work demonstrates that resistance to all types of stress declines with age. Based on our data, we speculate that the decrease in stress resistance with advancing age results from a genetically-programmed inactivation of stress response pathways, not accumulation of damage.

  15. Modelling subject-specific childhood growth using linear mixed-effect models with cubic regression splines.

    Science.gov (United States)

    Grajeda, Laura M; Ivanescu, Andrada; Saito, Mayuko; Crainiceanu, Ciprian; Jaganath, Devan; Gilman, Robert H; Crabtree, Jean E; Kelleher, Dermott; Cabrera, Lilia; Cama, Vitaliano; Checkley, William

    2016-01-01

    Childhood growth is a cornerstone of pediatric research. Statistical models need to consider individual trajectories to adequately describe growth outcomes. Specifically, well-defined longitudinal models are essential to characterize both population and subject-specific growth. Linear mixed-effect models with cubic regression splines can account for the nonlinearity of growth curves and provide reasonable estimators of population and subject-specific growth, velocity and acceleration. We provide a stepwise approach that builds from simple to complex models, and account for the intrinsic complexity of the data. We start with standard cubic splines regression models and build up to a model that includes subject-specific random intercepts and slopes and residual autocorrelation. We then compared cubic regression splines vis-à-vis linear piecewise splines, and with varying number of knots and positions. Statistical code is provided to ensure reproducibility and improve dissemination of methods. Models are applied to longitudinal height measurements in a cohort of 215 Peruvian children followed from birth until their fourth year of life. Unexplained variability, as measured by the variance of the regression model, was reduced from 7.34 when using ordinary least squares to 0.81 (p linear mixed-effect models with random slopes and a first order continuous autoregressive error term. There was substantial heterogeneity in both the intercept (p modeled with a first order continuous autoregressive error term as evidenced by the variogram of the residuals and by a lack of association among residuals. The final model provides a parametric linear regression equation for both estimation and prediction of population- and individual-level growth in height. We show that cubic regression splines are superior to linear regression splines for the case of a small number of knots in both estimation and prediction with the full linear mixed effect model (AIC 19,352 vs. 19

  16. Reinforced concrete membrane elements subjected to reversed cyclic in-plane shear stress

    International Nuclear Information System (INIS)

    Ohmori, N.; Tsubota, H.; Inoue, N.; Watanabe, S.; Kurihara, K.

    1987-01-01

    The response of reinforced concrete elements subjected to reversed cyclic in-plane shear stresses can be predicted by an analytical model, which considers equilibrium, compatibility and stress-strain relationships including hysteresis loop of unloading and reloading stages all expressed in terms of average stresses and average strains. The analytical results show that the dominant hysteretic behaviours in regard to decrease of stiffness during unloading, successive slip phenomena and restoration of compressive stiffness at the reloading stages are well simulated analytically. The results agree quite well with the observed behaviours. As for the envelope curve of the hysteretic response there remain the discrepancies that the stiffness and ultimate strength are a bit larger than the observed results, especially in the case of a panel with a large reinforcement ratio. Such descrepancies are also found in the predicted results of monotonic loading and more precise studies are necessary to evaluate more accurate envelope curves under not only reversed cyclic loading but also monotonic loading. (orig./HP)

  17. The relationship between bioclimatic thermal stress and subjective thermal sensation in pedestrian spaces

    Science.gov (United States)

    Pearlmutter, David; Jiao, Dixin; Garb, Yaakov

    2014-12-01

    Outdoor thermal comfort has important implications for urban planning and energy consumption in the built environment. To better understand the relation of subjective thermal experience to bioclimatic thermal stress in such contexts, this study compares micrometeorological and perceptual data from urban spaces in the hot-arid Negev region of Israel. Pedestrians reported on their thermal sensation in these spaces, whereas radiation and convection-related data were used to compute the Index of Thermal Stress (ITS) and physiologically equivalent temperature (PET). The former is a straightforward characterization of energy exchanges between the human body and its surroundings, without any conversion to an "equivalent temperature." Although the relation of ITS to subjective thermal sensation has been analyzed in the past under controlled indoor conditions, this paper offers the first analysis of this relation in an outdoor setting. ITS alone can account for nearly 60 % of the variance in pedestrians' thermal sensation under outdoor conditions, somewhat more than PET. A series of regressions with individual contextual variables and ITS identified those factors which accounted for additional variance in thermal sensation, whereas multivariate analyses indicated the considerable predictive power ( R-square = 0.74) of models including multiple contextual variables in addition to ITS. Our findings indicate that pedestrians experiencing variable outdoor conditions have a greater tolerance for incremental changes in thermal stress than has been shown previously under controlled indoor conditions, with a tapering of responses at high values of ITS. However, the thresholds of ITS corresponding to thermal "neutrality" and thermal "acceptability" are quite consistent regardless of context.

  18. Local heat stress and skin blood flowmotion in subjects with familial predisposition or newly diagnosed hypertension.

    Science.gov (United States)

    Gryglewska, Barbara; Nęcki, Mirosław; Cwynar, Marcin; Baron, Tomasz; Grodzicki, Tomasz

    2010-12-01

    The aim of the study was to investigate the skin microcirculation blood flow and flowmotion response to heat stress in normotensive subjects with familial predisposition to hypertension and in hypertensive patients. Normotensives without [NT(-)] or with [NT(+)] familial predisposition and subjects with newly diagnosed hypertension (HT) were studied. Clinic blood pressure (BP) measurements and ambulatory BP monitoring as well as laboratory assessments were performed. Resting (RF), heat (HF) and maximal heat (MHF) blood flows were measured using PeriFlux laser Doppler flowmetry (LDF) and expressed as absolute units (AU) and as index of cutaneous vascular conductance (CVC). Spectral analysis of the skin LDF signal was performed by means of the Perisoft dedicated software. Kruskall-Wallis analysis of variance, χ(2) statistic and multivariate reverse regression analysis were used for calculation. The studied population consisted of 70 persons (mean age 36.1 ± 10.3 years, 44.3% women): 17 NT(-), 22 NT(+) and 31 HT, age and gender matched. Higher values of body mass index (BMI), and insulin, glucose and triglyceride levels were observed in HT than in NT groups. RF, HF and MHF were similar in all study groups, but CVC of maximal heat flow differed (p=0.02); in particular, lower values were observed in the HT than in NT(-) group (p=0.01). The study groups differed with regard to total power (p=0.01) and myogenic (p=0.03) origin flowmotion with the lowest values in the NT(+) group. BMI and night BP characteristics were strong predictors of reduction of CVC, MHF and myogenic origin flowmotion. Skin microcirculation response to local heat stress is altered in hypertensive patients with decrease in maximal heat CVC values. Moreover, normotensive subjects with familial predisposition to hypertension are characterized by diminished myogenic origin of skin blood flowmotion.

  19. Gender-specific predictors of posttraumatic stress disorder in adolescents

    DEFF Research Database (Denmark)

    Donbaek, Dagmar Feddern; Elklit, Ask

    2015-01-01

    Gender is an important risk factor for both posttraumatic stress disorder (PTSD) and substance use disorders (SUD) in adolescents; however, little is known about the influence of gender when considering their common co-occurrence. This study examined whether problematic substance use, attachment...

  20. Effects of prenatal stress on anxiety- and depressive-like behaviors are sex-specific in prepubertal rats.

    Science.gov (United States)

    Iturra-Mena, Ann Mary; Arriagada-Solimano, Marcia; Luttecke-Anders, Ariane; Dagnino-Subiabre, Alexies

    2018-05-17

    The fetal brain is highly susceptible to stress in late pregnancy, with lifelong effects of stress on physiology and behavior. The aim of this study was to determine the physiological and behavioral effects of prenatal stress during the prepubertal period of female and male rats. We subjected pregnant Sprague-Dawley rats to a restraint stress protocol from gestational day 14 until 21, a critical period for fetal brain susceptibility to stress effects. Male and female offspring were subsequently assessed at postnatal day 24 for anxiety- and depressive-like behaviors, and spontaneous social interaction. We also assessed maternal behaviors and two stress markers: basal vs. acute-evoked stress levels of serum corticosterone and body weight gain. Prenatal stress did not affect the maternal behavior, while both female and male offspring had higher body weight gain. On the other hand, lower levels of corticosterone after acute stress stimulation as well as anxiety- and depressive-like behaviors were only evident in stressed males compared to control males. These results suggest that prenatal stress induced sex-specific effects on the hypothalamus-pituitary-adrenal (HPA) axis activity and on behavior during prepuberty. The HPA axis of prenatally stressed male rats was less active compared to control males, as well as they were more anxious and experienced depressive-like behaviors. Our results can be useful to study the neurobiological basis of childhood depression at a pre-clinical level. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  1. Vulnerability-specific stress generation: An examination of negative cognitive and interpersonal styles

    OpenAIRE

    Liu, Richard T.; Alloy, Lauren B.; Mastin, Becky M.; Choi, Jimmy Y.; Boland, Elaine M.; Jenkins, Abby L.

    2014-01-01

    Although there is substantial evidence documenting the stress generation effect in depression (i.e., the tendency for depression-prone individuals to experience higher rates of life stress to which they contribute), additional research is required to advance current understanding of the specific types of dependent stress (i.e., events influenced by characteristics and attendant behaviors of the individual) relevant to this effect. The present study tested an extension of the stress generation...

  2. Sensitivity of a subject-specific musculoskeletal model to the uncertainties on the joint axes location.

    Science.gov (United States)

    Martelli, Saulo; Valente, Giordano; Viceconti, Marco; Taddei, Fulvia

    2015-01-01

    Subject-specific musculoskeletal models have become key tools in the clinical decision-making process. However, the sensitivity of the calculated solution to the unavoidable errors committed while deriving the model parameters from the available information is not fully understood. The aim of this study was to calculate the sensitivity of all the kinematics and kinetics variables to the inter-examiner uncertainty in the identification of the lower limb joint models. The study was based on the computer tomography of the entire lower-limb from a single donor and the motion capture from a body-matched volunteer. The hip, the knee and the ankle joint models were defined following the International Society of Biomechanics recommendations. Using a software interface, five expert anatomists identified on the donor's images the necessary bony locations five times with a three-day time interval. A detailed subject-specific musculoskeletal model was taken from an earlier study, and re-formulated to define the joint axes by inputting the necessary bony locations. Gait simulations were run using OpenSim within a Monte Carlo stochastic scheme, where the locations of the bony landmarks were varied randomly according to the estimated distributions. Trends for the joint angles, moments, and the muscle and joint forces did not substantially change after parameter perturbations. The highest variations were as follows: (a) 11° calculated for the hip rotation angle, (b) 1% BW × H calculated for the knee moment and (c) 0.33 BW calculated for the ankle plantarflexor muscles and the ankle joint forces. In conclusion, the identification of the joint axes from clinical images is a robust procedure for human movement modelling and simulation.

  3. Subject-specific computational modeling of DBS in the PPTg area

    Directory of Open Access Journals (Sweden)

    Laura M. Zitella

    2015-07-01

    Full Text Available Deep brain stimulation (DBS in the pedunculopontine tegmental nucleus (PPTg has been proposed to alleviate medically intractable gait difficulties associated with Parkinson’s disease. Clinical trials have shown somewhat variable outcomes, stemming in part from surgical targeting variability, modulating fiber pathways implicated in side effects, and a general lack of mechanistic understanding of DBS in this brain region. Subject-specific computational models of DBS are a promising tool to investigate the underlying therapy and side effects. In this study, a parkinsonian rhesus macaque was implanted unilaterally with an 8-contact DBS lead in the PPTg region. Fiber tracts adjacent to PPTg, including the oculomotor nerve, central tegmental tract, and superior cerebellar peduncle, were reconstructed from a combination of pre-implant 7T MRI, post-implant CT, and post-mortem histology. These structures were populated with axon models and coupled with a finite element model simulating the voltage distribution in the surrounding neural tissue during stimulation. This study introduces two empirical approaches to evaluate model parameters. First, incremental monopolar cathodic stimulation (20Hz, 90µs pulse width was evaluated for each electrode, during which a right eyelid flutter was observed at the proximal four contacts (-1.0 to -1.4mA. These current amplitudes followed closely with model predicted activation of the oculomotor nerve when assuming an anisotropic conduction medium. Second, PET imaging was collected OFF-DBS and twice during DBS (two different contacts, which supported the model predicted activation of the central tegmental tract and superior cerebellar peduncle. Together, subject-specific models provide a framework to more precisely predict pathways modulated by DBS.

  4. Prepartum autobiographical memory specificity predicts post-traumatic stress symptoms following complicated pregnancy

    NARCIS (Netherlands)

    Hauer, Beatrijs J. A.; Wessel, Ineke; Engelhard, Iris M.; Peeters, Louis L.; Dalgleish, Tim

    2009-01-01

    Prior research has shown that reduced autobiographical memory specificity predicts an increase in post-traumatic stress severity in traumatised individuals. Studies have also demonstrated that reduced memory specificity predicts later symptoms of depression after pregnancy-related life stress. So

  5. Subjective well-being: gender differences in Holocaust survivors-specific and cross-national effects.

    Science.gov (United States)

    Carmel, Sara; King, David B; O'Rourke, Norm; Bachner, Yaacov G

    2017-06-01

    Subjective well-being (SWB) has become an important concept in evaluating older adults' quality of life. The cognitive and emotional evaluations which are used to appraise it differ in structure, characteristics, and effects on life. The purpose of this study was to support hypotheses regarding expected Holocaust survivors-specific effects and cross-cultural differences on three indicators of SWB. We recruited samples of 50 male and female Israeli Holocaust survivors, other older Israelis, and older Canadians (N = 300) for allowing us to distinguish survivors-specific effects from cross-national differences. State anxiety, depressive symptoms, and life-satisfaction were compared across groups of men and women. Where univariate differences were detected, post hoc comparisons were computed to determine which of the groups significantly differed. In general, a higher level of SWB was found among Canadians in comparison to both comparative Israeli groups. Level of depressive symptoms was significantly higher among women survivors than in the other two groups. Both groups of Israeli women had higher scores on anxiety than Canadian Women; less apparent were differences across groups of men. Life-satisfaction did not differ among the groups. Our findings regarding depression support the survivor-specific effect hypothesis for women, and a national effect on anxiety, but not any effect on life-satisfaction. These findings suggest significant differences in impacts of traumatic life events on cognitive versus emotional indicators of SWB. This issue should be further investigated due to its practical implications in use of various measures of SWB with people who experienced traumatic events.

  6. Omega-3 fatty acids alter behavioral and oxidative stress parameters in animals subjected to fenproporex administration.

    Science.gov (United States)

    Model, Camila S; Gomes, Lara M; Scaini, Giselli; Ferreira, Gabriela K; Gonçalves, Cinara L; Rezin, Gislaine T; Steckert, Amanda V; Valvassori, Samira S; Varela, Roger B; Quevedo, João; Streck, Emilio L

    2014-03-01

    Studies have consistently reported the participation of oxidative stress in bipolar disorder (BD). Evidences indicate that omega-3 (ω3) fatty acids play several important roles in brain development and functioning. Moreover, preclinical and clinical evidence suggests roles for ω3 fatty acids in BD. Considering these evidences, the present study aimed to investigate the effects of ω3 fatty acids on locomotor behavior and oxidative stress parameters (TBARS and protein carbonyl content) in brain of rats subjected to an animal model of mania induced by fenproporex. The fenproporex treatment increased locomotor behavior in saline-treated rats under reversion and prevention model, and ω3 fatty acids prevented fenproporex-related hyperactivity. Moreover, fenproporex increased protein carbonyls in the prefrontal cortex and cerebral cortex, and the administration of ω3 fatty acids reversed this effect. Lipid peroxidation products also are increased in prefrontal cortex, striatum, hippocampus and cerebral after fenproporex administration, but ω3 fatty acids reversed this damage only in the hippocampus. On the other hand, in the prevention model, fenproporex increased carbonyl content only in the cerebral cortex, and administration of ω3 fatty acids prevented this damage. Additionally, the administration of fenproporex resulted in a marked increased of TBARS in the prefrontal cortex, hippocampus, striatum and cerebral cortex, and prevent this damage in the prefrontal cortex, hippocampus and striatum. In conclusion, we are able to demonstrate that fenproporex-induced hyperlocomotion and damage through oxidative stress were prevented by ω3 fatty acids. Thus, the ω3 fatty acids may be important adjuvant therapy of bipolar disorder.

  7. The Assessing of the Failure Behavior of Glass/Polyester Composites Subject to Quasi Static Stresses

    Science.gov (United States)

    Stanciu, M. D.; Savin, A.; Teodorescu-Drăghicescu, H.

    2017-06-01

    Using glass fabric reinforced composites for structure of wind turbine blades requires high mechanical strengths especially to cyclic stresses. Studies have shown that approximately 50% of composite material failure occurs because of fatigue. Composites behavior to cyclic stresses involves three stages regarding to stiffness variation: the first stage is characterized by the accelerated decline of stiffness with micro-cracks, the second stage - a slight decrease of stiffness characterized by the occurrence of delamination and third stage characterized by higher decreases of resistance and occurrence of fracture thereof. The aim of the paper is to analyzed the behavior of composites reinforced with glass fibers fabric type RT500 and polyester resin subjected to tensile cyclic loading with pulsating quasi-static regime with asymmetry coefficient R = 0. The samples were tested with the universal tensile machine LS100 Lloyd Instruments Plus, with a load capacity of 100 kN. The load was applied with different speeds of 1 mm/min, 10 mm/min and 20 mm/min. After tests, it was observed that the greatest permanent strains were recorded in the first load cycles when the total energy storage by material was lost due to internal friction. With increasing number of cycles, the glass/polyester composites ability to store energy of deformation decreases, the flow phenomenon characterized by large displacements to smaller loading forces appearing.

  8. Aging causes decreased resistance to multiple stresses and a failure to activate specific stress response pathways

    OpenAIRE

    Dues, Dylan J.; Andrews, Emily K.; Schaar, Claire E.; Bergsma, Alexis L.; Senchuk, Megan M.; Van Raamsdonk, Jeremy M.

    2016-01-01

    In this work, we examine the relationship between stress resistance and aging. We find that resistance to multiple types of stress peaks during early adulthood and then declines with age. To dissect the underlying mechanisms, we use C. elegans transcriptional reporter strains that measure the activation of different stress responses including: the heat shock response, mitochondrial unfolded protein response, endoplasmic reticulum unfolded protein response, hypoxia response, SKN-1-mediated oxi...

  9. Foot medial longitudinal-arch deformation during quiet standing and gait in subjects with medial tibial stress syndrome

    DEFF Research Database (Denmark)

    Bandholm, Thomas Quaade; Boysen, Lisbeth; Haugaard, Stine

    2008-01-01

    The objective of this study was to investigate (1) if subjects with medial tibial stress syndrome demonstrate increased navicular drop and medial longitudinal-arch deformation during quiet standing and gait compared with healthy subjects, and (2) the relationship between medial longitudinal-arch ...

  10. Central Pressure Appraisal: Clinical Validation of a Subject-Specific Mathematical Model.

    Directory of Open Access Journals (Sweden)

    Francesco Tosello

    Full Text Available Current evidence suggests that aortic blood pressure has a superior prognostic value with respect to brachial pressure for cardiovascular events, but direct measurement is not feasible in daily clinical practice.The aim of the present study is the clinical validation of a multiscale mathematical model for non-invasive appraisal of central blood pressure from subject-specific characteristics.A total of 51 young male were selected for the present study. Aortic systolic and diastolic pressure were estimated with a mathematical model and were compared to the most-used non-invasive validated technique (SphygmoCor device, AtCor Medical, Australia. SphygmoCor was calibrated through diastolic and systolic brachial pressure obtained with a sphygmomanometer, while model inputs consist of brachial pressure, height, weight, age, left-ventricular end-systolic and end-diastolic volumes, and data from a pulse wave velocity study.Model-estimated systolic and diastolic central blood pressures resulted to be significantly related to SphygmoCor-assessed central systolic (r = 0.65 p <0.0001 and diastolic (r = 0.84 p<0.0001 blood pressures. The model showed a significant overestimation of systolic pressure (+7.8 (-2.2;14 mmHg, p = 0.0003 and a significant underestimation of diastolic values (-3.2 (-7.5;1.6, p = 0.004, which imply a significant overestimation of central pulse pressure. Interestingly, model prediction errors mirror the mean errors reported in large meta-analysis characterizing the use of the SphygmoCor when non-invasive calibration is performed.In conclusion, multi-scale mathematical model predictions result to be significantly related to SphygmoCor ones. Model-predicted systolic and diastolic aortic pressure resulted in difference of less than 10 mmHg in the 51% and 84% of the subjects, respectively, when compared with SphygmoCor-obtained pressures.

  11. Stresses in a curved pipe subject to an in-plane bending moment

    International Nuclear Information System (INIS)

    Hofmann, E.; Heeschen, U.

    1979-01-01

    The design of the KWU-primary component supports is mainly defined by the loads of the postulated pipe breaks. To estimate the maximum loading of a component support it is necessary to know the maximum in-plane bending moment (opening and closing) that can be transmitted by a pipe bend. Another reason for such information is that the displacements and distortions of the components cause higher stresses in elbows than in straight pipes. With a detailed knowledge of the deformation characteristic of a pipe bend an integrity analysis could be done without an expensive plastic system analysis. With this purpose in mind experiments were performed with straight pipes and pipe bends of different dimensions subject to in-plane bending moments. The experimental results give the ratio between the maximum transmittable moment of a pipe bend to that of a straight pipe or, the distortion of the end cross-sections and the flattening of the elbow cross-section. An attempt is made to derive simple expressions for estimating the behaviour at pipe elbows. Parallel to the experiments calculations were done for the straight pipe and elbow with a finite difference code with plastic capabilities. The results of the experiment and calculation are compared with the formulas of the ASME-Code section III subjection NB. (orig.)

  12. Response to Dietary Supplementation of Glutamine in Broiler Chickens Subjected to Transportation Stress

    Directory of Open Access Journals (Sweden)

    Majid SHAKERI

    2016-07-01

    Full Text Available The main purpose of this study was to determine effects of glutamine supplementation on performance and blood parameters including Hsp70 and acute phase protein when chicken were subjected to transportation stress. A total of four hundred day-old-male cobb-500 chicks were obtained directly from a local hatchery. The chicks were allotted to two groups as: immediate placement (1 hour after hatching with access to feed and water and placement after 24h transportation without access to feed and water. The experiment consisted of a factorial arrangement of 2 different diets and 2 different time of placement. Chicks from each placement group were fed either basal diet or basal diet + 1% glutamine from 1 to 21 days of age. The results indicated that dietary glutamine improved the body weight gain and feed conversion ratio significantly when chicks were subjected to delayed or immediate placement. In conclusion, supplementing chicken with glutamine in diet can reduce negative effects of delayed access to feed and water during transportation. Moreover, APP concentration and HSP70 level were positively affected when chicks supplemented with glutamine in the diet.

  13. Bayesian longitudinal segmentation of hippocampal substructures in brain MRI using subject-specific atlases.

    Science.gov (United States)

    Iglesias, Juan Eugenio; Van Leemput, Koen; Augustinack, Jean; Insausti, Ricardo; Fischl, Bruce; Reuter, Martin

    2016-11-01

    The hippocampal formation is a complex, heterogeneous structure that consists of a number of distinct, interacting subregions. Atrophy of these subregions is implied in a variety of neurodegenerative diseases, most prominently in Alzheimer's disease (AD). Thanks to the increasing resolution of MR images and computational atlases, automatic segmentation of hippocampal subregions is becoming feasible in MRI scans. Here we introduce a generative model for dedicated longitudinal segmentation that relies on subject-specific atlases. The segmentations of the scans at the different time points are jointly computed using Bayesian inference. All time points are treated the same to avoid processing bias. We evaluate this approach using over 4700 scans from two publicly available datasets (ADNI and MIRIAD). In test-retest reliability experiments, the proposed method yielded significantly lower volume differences and significantly higher Dice overlaps than the cross-sectional approach for nearly every subregion (average across subregions: 4.5% vs. 6.5%, Dice overlap: 81.8% vs. 75.4%). The longitudinal algorithm also demonstrated increased sensitivity to group differences: in MIRIAD (69 subjects: 46 with AD and 23 controls), it found differences in atrophy rates between AD and controls that the cross sectional method could not detect in a number of subregions: right parasubiculum, left and right presubiculum, right subiculum, left dentate gyrus, left CA4, left HATA and right tail. In ADNI (836 subjects: 369 with AD, 215 with early cognitive impairment - eMCI - and 252 controls), all methods found significant differences between AD and controls, but the proposed longitudinal algorithm detected differences between controls and eMCI and differences between eMCI and AD that the cross sectional method could not find: left presubiculum, right subiculum, left and right parasubiculum, left and right HATA. Moreover, many of the differences that the cross-sectional method already found

  14. Discrimination, Subjective Wellbeing, and the Role of Gender: A Mediation Model of LGB Minority Stress.

    Science.gov (United States)

    Conlin, Sarah E; Douglass, Richard P; Ouch, Staci

    2017-10-26

    The present study examined the link between discrimination and the three components of subjective wellbeing (positive and negative affect and life satisfaction) among a cisgender sample of lesbian, gay, and bisexual (LGB) adults. Specifically, we investigated internalized homonegativity and expectations of rejection as potential mediators of the links between discrimination and subjective wellbeing among a sample of 215 participants. Results from our structural equation model demonstrated a strong, positive direct link between discrimination and negative affect. Discrimination also had small, negative indirect effects on life satisfaction through our two mediators. Interestingly, neither discrimination nor our two mediators were related with positive affect, demonstrating the need for future research to uncover potential buffers of this link. Finally, our model evidenced configural, metric, and scalar invariance, suggesting that our model applies well for both women and men. Practical implications and future directions for research are discussed.

  15. Patient-specific AAA wall stress analysis: 99-percentile versus peak stress

    NARCIS (Netherlands)

    Speelman, L.; Bosboom, E.M.H.; Schurink, G.W.H.; Hellenthal, F.A.M.V.I.; Buth, J.; Breeuwer, M.; Jacobs, M.J.; Vosse, van de F.N.

    2008-01-01

    Objective Biomechanically, rupture of an Abdominal Aortic Aneurysm (AAA) occurs when the stress acting on the wall due to the blood pressure, exceeds the strength of the wall. Peak wall stress estimations, based on CT reconstruction, may be prone to observer variation. This study focuses on the

  16. Initial stress and nonlinear material behavior in patient-specific AAA wall stress analysis

    NARCIS (Netherlands)

    Speelman, L.; Bosboom, E.M.H.; Schurink, G.W.H.; Buth, J.; Breeuwer, M.; Jacobs, M.J.; Vosse, van de F.N.

    2009-01-01

    Rupture risk estimation of abdominal aortic aneurysms (AAA) is currently based on the maximum diameter of the AAA. A more critical approach is based on AAA wall stress analysis. For that, in most cases, the AAA geometry is obtained from CT-data and treated as a stress free geometry. However, during

  17. Subjectively and objectively measured sleep with and without posttraumatic stress disorder and trauma exposure.

    Science.gov (United States)

    Kobayashi, Ihori; Huntley, Edward; Lavela, Joseph; Mellman, Thomas A

    2012-07-01

    Although reports of sleep disturbances are common among individuals with posttraumatic stress disorder (PTSD), results of polysomnographic (PSG) studies have inconsistently documented abnormalities and have therefore suggested "sleep state misperception." The authors' study objectives were to compare sleep parameters measured objectively and subjectively in the laboratory and at home in civilians with and without trauma exposure and PTSD. Cross-sectional study. PSG recordings in a sleep laboratory and actigraphic recordings in participants' homes. One hundred three urban-residing African Americans with and without trauma exposure and PTSD who participated in a larger study. N/A. Sleep parameters (total sleep time [TST], sleep onset latency [SOL], and wake after sleep onset [WASO]) were assessed using laboratory PSG and home actigraphy. A sleep diary was completed in the morning after PSG and actigraphy recordings. Habitual TST, SOL, and WASO were assessed using a sleep questionnaire. The Clinician Administered PTSD Scale was administered to assess participants' trauma exposure and PTSD diagnostic status. Participants, regardless of their trauma exposure/PTSD status, underestimated WASO in the diary and questionnaire relative to actigraphy and overestimated SOL in the diary relative to PSG. Among participants with current PTSD, TST diary estimates did not differ from the actigraphy measure in contrast with those without current PTSD who overestimated TST. No other significant group differences in discrepancies between subjective and objective sleep measures were found. Discrepancies between subjectively and objectively measured sleep parameters were not associated with trauma exposure or PTSD. This challenges prior assertions that individuals with PTSD overreport their sleep disturbances.

  18. Developmental Dynamics of General and School-Subject-Specific Components of Academic Self-Concept, Academic Interest, and Academic Anxiety.

    Science.gov (United States)

    Gogol, Katarzyna; Brunner, Martin; Preckel, Franzis; Goetz, Thomas; Martin, Romain

    2016-01-01

    The present study investigated the developmental dynamics of general and subject-specific (i.e., mathematics, French, and German) components of students' academic self-concept, anxiety, and interest. To this end, the authors integrated three lines of research: (a) hierarchical and multidimensional approaches to the conceptualization of each construct, (b) longitudinal analyses of bottom-up and top-down developmental processes across hierarchical levels, and (c) developmental processes across subjects. The data stemmed from two longitudinal large-scale samples (N = 3498 and N = 3863) of students attending Grades 7 and 9 in Luxembourgish schools. Nested-factor models were applied to represent each construct at each grade level. The analyses demonstrated that several characteristics were shared across constructs. All constructs were multidimensional in nature with respect to the different subjects, showed a hierarchical organization with a general component at the apex of the hierarchy, and had a strong separation between the subject-specific components at both grade levels. Further, all constructs showed moderate differential stabilities at both the general (0.42 < r < 0.55) and subject-specific levels (0.45 < r < 0.73). Further, little evidence was found for top-down or bottom-up developmental processes. Rather, general and subject-specific components in Grade 9 proved to be primarily a function of the corresponding components in Grade 7. Finally, change in several subject-specific components could be explained by negative effects across subjects.

  19. Developmental Dynamics of General and School-Subject-Specific Components of Academic Self-Concept, Academic Interest, and Academic Anxiety

    Directory of Open Access Journals (Sweden)

    Katarzyna eGogol

    2016-03-01

    Full Text Available The present study investigated the developmental dynamics of general and subject-specific (i.e., mathematics, French, and German components of students’ academic self-concept, anxiety, and interest. To this end, the authors integrated three lines of research: (a hierarchical and multidimensional approaches to the conceptualization of each construct, (b longitudinal analyses of bottom-up and top-down developmental processes across hierarchical levels, and (c ipsative developmental processes across subjects. The data stemmed from two longitudinal large-scale samples (N = 3,498 and N = 3,863 of students attending Grades 7 and 9 in Luxembourgish schools. Nested-factor models were applied to represent each construct at each grade level. The analyses demonstrated that several characteristics were shared across constructs. All constructs were multidimensional in nature with respect to the different subjects, showed a hierarchical organization with a general component at the apex of the hierarchy, and had a strong separation between the subject-specific components at both grade levels. Further, all constructs showed moderate differential stabilities at both the general (.42 < r < .55 and subject-specific levels (.45 < r < .73. Further, little evidence was found for top-down or bottom-up developmental processes. Rather, general and subject-specific components in Grade 9 proved to be primarily a function of the corresponding components in Grade 7. Finally, change in several subject-specific components could be explained by negative, ipsative effects across subjects.

  20. Developmental Dynamics of General and School-Subject-Specific Components of Academic Self-Concept, Academic Interest, and Academic Anxiety

    Science.gov (United States)

    Gogol, Katarzyna; Brunner, Martin; Preckel, Franzis; Goetz, Thomas; Martin, Romain

    2016-01-01

    The present study investigated the developmental dynamics of general and subject-specific (i.e., mathematics, French, and German) components of students' academic self-concept, anxiety, and interest. To this end, the authors integrated three lines of research: (a) hierarchical and multidimensional approaches to the conceptualization of each construct, (b) longitudinal analyses of bottom-up and top-down developmental processes across hierarchical levels, and (c) developmental processes across subjects. The data stemmed from two longitudinal large-scale samples (N = 3498 and N = 3863) of students attending Grades 7 and 9 in Luxembourgish schools. Nested-factor models were applied to represent each construct at each grade level. The analyses demonstrated that several characteristics were shared across constructs. All constructs were multidimensional in nature with respect to the different subjects, showed a hierarchical organization with a general component at the apex of the hierarchy, and had a strong separation between the subject-specific components at both grade levels. Further, all constructs showed moderate differential stabilities at both the general (0.42 < r < 0.55) and subject-specific levels (0.45 < r < 0.73). Further, little evidence was found for top-down or bottom-up developmental processes. Rather, general and subject-specific components in Grade 9 proved to be primarily a function of the corresponding components in Grade 7. Finally, change in several subject-specific components could be explained by negative effects across subjects. PMID:27014162

  1. High-resolution subject-specific mitral valve imaging and modeling: experimental and computational methods.

    Science.gov (United States)

    Toma, Milan; Bloodworth, Charles H; Einstein, Daniel R; Pierce, Eric L; Cochran, Richard P; Yoganathan, Ajit P; Kunzelman, Karyn S

    2016-12-01

    The diversity of mitral valve (MV) geometries and multitude of surgical options for correction of MV diseases necessitates the use of computational modeling. Numerical simulations of the MV would allow surgeons and engineers to evaluate repairs, devices, procedures, and concepts before performing them and before moving on to more costly testing modalities. Constructing, tuning, and validating these models rely upon extensive in vitro characterization of valve structure, function, and response to change due to diseases. Micro-computed tomography ([Formula: see text]CT) allows for unmatched spatial resolution for soft tissue imaging. However, it is still technically challenging to obtain an accurate geometry of the diastolic MV. We discuss here the development of a novel technique for treating MV specimens with glutaraldehyde fixative in order to minimize geometric distortions in preparation for [Formula: see text]CT scanning. The technique provides a resulting MV geometry which is significantly more detailed in chordal structure, accurate in leaflet shape, and closer to its physiological diastolic geometry. In this paper, computational fluid-structure interaction (FSI) simulations are used to show the importance of more detailed subject-specific MV geometry with 3D chordal structure to simulate a proper closure validated against [Formula: see text]CT images of the closed valve. Two computational models, before and after use of the aforementioned technique, are used to simulate closure of the MV.

  2. Task-specific compensation and recovery following focal motor cortex lesion in stressed rats.

    Science.gov (United States)

    Kirkland, Scott W; Smith, Lori K; Metz, Gerlinde A

    2012-03-01

    One reason for the difficulty to develop effective therapies for stroke is that intrinsic factors, such as stress, may critically influence pathological mechanisms and recovery. In cognitive tasks, stress can both exaggerate and alleviate functional loss after focal ischemia in rodents. Using a comprehensive motor assessment in rats, this study examined if chronic stress and corticosterone treatment affect skill recovery and compensation in a task-specific manner. Groups of rats received daily restraint stress or oral corticosterone supplementation for two weeks prior to a focal motor cortex lesion. After lesion, stress and corticosterone treatments continued for three weeks. Motor performance was assessed in two skilled reaching tasks, skilled walking, forelimb inhibition, forelimb asymmetry and open field behavior. The results revealed that persistent stress and elevated corticosterone levels mainly limit motor recovery. Treated animals dropped larger amounts of food in successful reaches and showed exaggerated loss of forelimb inhibition early after lesion. Stress also caused a moderate, but non-significant increase in infarct size. By contrast, stress and corticosterone treatments promoted reaching success and other quantitative measures in the tray reaching task. Comparative analysis revealed that improvements are due to task-specific development of compensatory strategies. These findings suggest that stress and stress hormones may partially facilitate task-specific and adaptive compensatory movement strategies. The observations support the notion that hypothalamic-pituitary-adrenal axis activation may be a key determinant of recovery and motor system plasticity after ischemic stroke.

  3. Language-specific stress perception by 9-month-old French and Spanish infants.

    Science.gov (United States)

    Skoruppa, Katrin; Pons, Ferran; Christophe, Anne; Bosch, Laura; Dupoux, Emmanuel; Sebastián-Gallés, Núria; Limissuri, Rita Alves; Peperkamp, Sharon

    2009-11-01

    During the first year of life, infants begin to have difficulties perceiving non-native vowel and consonant contrasts, thus adapting their perception to the phonetic categories of the target language. In this paper, we examine the perception of a non-segmental feature, i.e. stress. Previous research with adults has shown that speakers of French (a language with fixed stress) have great difficulties in perceiving stress contrasts (Dupoux, Pallier, Sebastián & Mehler, 1997), whereas speakers of Spanish (a language with lexically contrastive stress) perceive these contrasts as accurately as segmental contrasts. We show that language-specific differences in the perception of stress likewise arise during the first year of life. Specifically, 9-month-old Spanish infants successfully distinguish between stress-initial and stress-final pseudo-words, while French infants of this age show no sign of discrimination. In a second experiment using multiple tokens of a single pseudo-word, French infants of the same age successfully discriminate between the two stress patterns, showing that they are able to perceive the acoustic correlates of stress. Their failure to discriminate stress patterns in the first experiment thus reflects an inability to process stress at an abstract, phonological level.

  4. Microarray meta-analysis to explore abiotic stress-specific gene expression patterns in Arabidopsis.

    Science.gov (United States)

    Shen, Po-Chih; Hour, Ai-Ling; Liu, Li-Yu Daisy

    2017-12-01

    Abiotic stresses are the major limiting factors that affect plant growth, development, yield and final quality. Deciphering the underlying mechanisms of plants' adaptations to stresses using few datasets might overlook the different aspects of stress tolerance in plants, which might be simultaneously and consequently operated in the system. Fortunately, the accumulated microarray expression data offer an opportunity to infer abiotic stress-specific gene expression patterns through meta-analysis. In this study, we propose to combine microarray gene expression data under control, cold, drought, heat, and salt conditions and determined modules (gene sets) of genes highly associated with each other according to the observed expression data. By analyzing the expression variations of the Eigen genes from different conditions, we had identified two, three, and five gene modules as cold-, heat-, and salt-specific modules, respectively. Most of the cold- or heat-specific modules were differentially expressed to a particular degree in shoot samples, while most of the salt-specific modules were differentially expressed to a particular degree in root samples. A gene ontology (GO) analysis on the stress-specific modules suggested that the gene modules exclusively enriched stress-related GO terms and that different genes under the same GO terms may be alternatively disturbed in different conditions. The gene regulatory events for two genes, DREB1A and DEAR1, in the cold-specific gene module had also been validated, as evidenced through the literature search. Our protocols study the specificity of the gene modules that were specifically activated under a particular type of abiotic stress. The biplot can also assist to visualize the stress-specific gene modules. In conclusion, our approach has the potential to further elucidate mechanisms in plants and beneficial for future experiments design under different abiotic stresses.

  5. Rivulet flow round a horizontal cylinder subject to a uniform surface shear stress

    KAUST Repository

    Paterson, C.

    2014-09-14

    © 2014 © The Author, 2014. Published by Oxford University Press; all rights reserved. For Permissions, please email: journals.permissions@oup.com. The steady flow of a slowly varying rivulet with prescribed flux in the azimuthal direction round a large stationary horizontal cylinder subject to a prescribed uniform azimuthal surface shear stress is investigated. In particular, we focus on the case where the volume flux is downwards but the shear stress is upwards, for which there is always a solution corresponding to a rivulet flowing down at least part of one side of the cylinder. We consider both a rivulet with constant non-zero contact angle but slowly varying width (that is, de-pinned contact lines) and a rivulet with constant width but slowly varying contact angle (that is, pinned contact lines), and show that they have qualitatively different behaviour. When shear is present, a rivulet with constant non-zero contact angle can never run all the way from the top to the bottom of the cylinder, and so we consider the scenario in which an infinitely wide two-dimensional film of uniform thickness covers part of the upper half of the cylinder and \\'breaks\\' into a single rivulet with constant non-zero contact angle. In contrast, a sufficiently narrow rivulet with constant width can run all the way from the top to the bottom of the cylinder, whereas a wide rivulet can do so only if its contact lines de-pin, and so we consider the scenario in which the contact lines of a wide rivulet de-pin on the lower half of the cylinder.

  6. Oxidative Stress and Antioxidants in Tomato (Solanum lycopersicum) Plants Subjected to Boron Toxicity

    Science.gov (United States)

    Cervilla, Luis M.; Blasco, Begoña; Ríos, Juan J.; Romero, Luis; Ruiz, Juan M.

    2007-01-01

    Background and Aims Boron (B) toxicity triggers the formation of reactive oxygen species in plant tissues. However, there is still a lack of knowledge as to how B toxicity affects the plant antioxidant defence system. It has been suggested that ascorbate could be important against B stress, although existing information is limited in this respect. The objective of this study was to analyse how ascorbate and some other components of the antioxidant network respond to B toxicity. Methods Two tomato (Solanum lycopersicum) cultivars (‘Kosaco’ and ‘Josefina’) were subjected to 0·05 (control), 0·5 and 2 mm B. The following were studied in leaves: dry weight; relative leaf growth rate; total and free B; H2O2; malondialdehyde; ascorbate; glutathione; sugars; total non-enzymatic antioxidant activity, and the activity of superoxide dismutase, catalase, ascorbate peroxidase, monodehydroascorbate reductase, dehydroascorbate reductase, glutathione reductase, ascorbate oxidase and l-galactose dehydrogenase. Key Results The B-toxicity treatments diminished growth and boosted the amount of B, malondialdehyde and H2O2 in the leaves of the two cultivars, these trends being more pronounced in ‘Josefina’ than in ‘Kosaco’. B toxicity increased ascorbate concentration in both cultivars and increased glutathione only in ‘Kosaco’. Activities of antioxidant- and ascorbate-metabolizing enzymes were also induced. Conclusions High B concentration in the culture medium provokes oxidative damage in tomato leaves and induces a general increase in antioxidant enzyme activity. In particular, B toxicity increased ascorbate pool size. It also increased the activity of l-galactose dehydrogenase, an enzyme involved in ascorbate biosynthesis, and the activity of enzymes of the Halliwell–Asada cycle. This work therefore provides a starting point towards a better understanding of the role of ascorbate in the plant response against B stress. PMID:17660516

  7. Development of a Subject-Specific Foot-Ground Contact Model for Walking.

    Science.gov (United States)

    Jackson, Jennifer N; Hass, Chris J; Fregly, Benjamin J

    2016-09-01

    largest errors in AP CoP occurred at the beginning and end of stance phase when the vertical ground reaction force (vGRF) was small. Subject-specific deformable foot-ground contact models created using this approach should enable changes in foot-ground contact pattern to be predicted accurately by gait optimization studies, which may lead to improvements in personalized rehabilitation medicine.

  8. The Role of Trauma-Specific Irrational Beliefs and Sociodemographic Risk Factors in Posttraumatic Stress Responses

    OpenAIRE

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

    2013-01-01

    Posttraumatic stress responses have been linked to a range of social-cognitive and sociodemographic factors. Rational Emotive Behaviour Therapy suggests that responding to a traumatic life event with a set of irrational beliefs should play a crucial role in predicting the development of posttraumatic stress disorder (PTSD: Ellis, 2001). The current study assessed the role of trauma-specific irrational beliefs in the prediction of clinically relevant posttraumatic stress responses, while contr...

  9. Sex-specific hippocampal 5-hydroxymethylcytosine is disrupted in response to acute stress.

    Science.gov (United States)

    Papale, Ligia A; Li, Sisi; Madrid, Andy; Zhang, Qi; Chen, Li; Chopra, Pankaj; Jin, Peng; Keleş, Sündüz; Alisch, Reid S

    2016-12-01

    Environmental stress is among the most important contributors to increased susceptibility to develop psychiatric disorders. While it is well known that acute environmental stress alters gene expression, the molecular mechanisms underlying these changes remain largely unknown. 5-hydroxymethylcytosine (5hmC) is a novel environmentally sensitive epigenetic modification that is highly enriched in neurons and is associated with active neuronal transcription. Recently, we reported a genome-wide disruption of hippocampal 5hmC in male mice following acute stress that was correlated to altered transcript levels of genes in known stress related pathways. Since sex-specific endocrine mechanisms respond to environmental stimulus by altering the neuronal epigenome, we examined the genome-wide profile of hippocampal 5hmC in female mice following exposure to acute stress and identified 363 differentially hydroxymethylated regions (DhMRs) linked to known (e.g., Nr3c1 and Ntrk2) and potentially novel genes associated with stress response and psychiatric disorders. Integration of hippocampal expression data from the same female mice found stress-related hydroxymethylation correlated to altered transcript levels. Finally, characterization of stress-induced sex-specific 5hmC profiles in the hippocampus revealed 778 sex-specific acute stress-induced DhMRs some of which were correlated to altered transcript levels that produce sex-specific isoforms in response to stress. Together, the alterations in 5hmC presented here provide a possible molecular mechanism for the adaptive sex-specific response to stress that may augment the design of novel therapeutic agents that will have optimal effectiveness in each sex. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  10. Vulnerability-specific stress generation: An examination of negative cognitive and interpersonal styles

    Science.gov (United States)

    Liu, Richard T.; Alloy, Lauren B.; Mastin, Becky M.; Choi, Jimmy Y.; Boland, Elaine M.; Jenkins, Abby L.

    2014-01-01

    Although there is substantial evidence documenting the stress generation effect in depression (i.e., the tendency for depression-prone individuals to experience higher rates of life stress to which they contribute), additional research is required to advance current understanding of the specific types of dependent stress (i.e., events influenced by characteristics and attendant behaviors of the individual) relevant to this effect. The present study tested an extension of the stress generation hypothesis, in which the content of dependent stress that is produced by depression-prone individuals is contingent upon, and matches, the nature of their particular vulnerabilities. This extension was tested within the context of two cognitive models (i.e., hopelessness theory [Abramson, Metalsky, & Alloy, 1989] and Cole’s [1990, 1991] competency-based model) and two interpersonal models (i.e., Swann’s [1987] self-verification theory and Coyne’s [1976] interpersonal theory) of depression. Overall, support was obtained for vulnerability-specific stress generation. Specifically, in analyses across vulnerability domains, evidence of stress-generation specificity was found for all domain-specific cognitive vulnerabilities except self-perceived social competence. The within-domain analyses for cognitive vulnerabilities produced more mixed results, but were largely supportive. Additionally, excessive reassurance-seeking was specifically predictive of dependent stress in the social domain, and moderated, but did not mediate, the relation between negative inferential styles overall and in the interpersonal domain and their corresponding generated stress. Finally, no evidence was found for a stress generation effect with negative feedback-seeking. PMID:24679143

  11. Intervarietal variations in various oxidative stress markers and antioxidant potential of finger millet (Eleusine coracana) subjected to drought stress.

    Science.gov (United States)

    Bartwal, Arti; Pande, Anjali; Sharma, Priyadarshini; Arora, Sandeep

    2016-07-01

    Drought is a major form of abiotic stress leading to lower crop productivity. Experiment was carried out for selecting the most tolerant genotype among six different genotypes of finger millet under drought stress. Seeds of six finger millet genotypes were sown in pots and grown for 35 days. After this period, drought was induced by withholding watering for stressed plants while control plants were watered regularly for comparison. Among all six different varieties of finger millet screened (PR202, PES400, PRM6107, VL283, VL328 and VL149) under varying intensities of drought stress,PRM6107 and PR202 showed highest stress tolerance by limiting excessive accumulation of reactive oxygen species (ROS) through activation of ROS scavenging antioxidative enzymes. A 200% increase in ascorbate content was recorded in PRM6107 and PR202, while in other varieties limited increase in ascorbate content was observed. Maximum decrease in chlorophyll content was observed in VL328 (83%) while least drop was observed in VL149 (65%). Relative water content indicated that PR202 was able to retain maximum water content under stress, as it recorded least drop in relative water content (55%), contributing to its better survival under stress. In conclusion finger millet genotypes PRM6107 and PR202 possessed maximum drought tolerance potential and thus may be used for allele mining of drought tolerant genes, which can further be employed for the development of more drought stress tolerant staple crops using biotechnological approach.

  12. Soft tissue artifact compensation in knee kinematics by multi-body optimization: Performance of subject-specific knee joint models.

    Science.gov (United States)

    Clément, Julien; Dumas, Raphaël; Hagemeister, Nicola; de Guise, Jaques A

    2015-11-05

    Soft tissue artifact (STA) distort marker-based knee kinematics measures and make them difficult to use in clinical practice. None of the current methods designed to compensate for STA is suitable, but multi-body optimization (MBO) has demonstrated encouraging results and can be improved. The goal of this study was to develop and validate the performance of knee joint models, with anatomical and subject-specific kinematic constraints, used in MBO to reduce STA errors. Twenty subjects were recruited: 10 healthy and 10 osteoarthritis (OA) subjects. Subject-specific knee joint models were evaluated by comparing dynamic knee kinematics recorded by a motion capture system (KneeKG™) and optimized with MBO to quasi-static knee kinematics measured by a low-dose, upright, biplanar radiographic imaging system (EOS(®)). Errors due to STA ranged from 1.6° to 22.4° for knee rotations and from 0.8 mm to 14.9 mm for knee displacements in healthy and OA subjects. Subject-specific knee joint models were most effective in compensating for STA in terms of abduction-adduction, inter-external rotation and antero-posterior displacement. Root mean square errors with subject-specific knee joint models ranged from 2.2±1.2° to 6.0±3.9° for knee rotations and from 2.4±1.1 mm to 4.3±2.4 mm for knee displacements in healthy and OA subjects, respectively. Our study shows that MBO can be improved with subject-specific knee joint models, and that the quality of the motion capture calibration is critical. Future investigations should focus on more refined knee joint models to reproduce specific OA knee geometry and physiology. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Tissue-specific and cation/anion-specific DNA methylation variations occurred in C. virgata in response to salinity stress.

    Directory of Open Access Journals (Sweden)

    Xiang Gao

    Full Text Available Salinity is a widespread environmental problem limiting productivity and growth of plants. Halophytes which can adapt and resist certain salt stress have various mechanisms to defend the higher salinity and alkalinity, and epigenetic mechanisms especially DNA methylation may play important roles in plant adaptability and plasticity. In this study, we aimed to investigate the different influences of various single salts (NaCl, Na2SO4, NaHCO3, Na2CO3 and their mixed salts on halophyte Chloris. virgata from the DNA methylation prospective, and discover the underlying relationships between specific DNA methylation variations and specific cations/anions through the methylation-sensitive amplification polymorphism analysis. The results showed that the effects on DNA methylation variations of single salts were ranked as follows: Na2CO3> NaHCO3> Na2SO4> NaCl, and their mixed salts exerted tissue-specific effects on C. virgata seedlings. Eight types of DNA methylation variations were detected and defined in C. virgata according to the specific cations/anions existed in stressful solutions; in addition, mix-specific and higher pH-specific bands were the main type in leaves and roots independently. These findings suggested that mixed salts were not the simple combination of single salts. Furthermore, not only single salts but also mixed salts showed tissue-specific and cations/anions-specific DNA methylation variations.

  14. Tissue-specific and cation/anion-specific DNA methylation variations occurred in C. virgata in response to salinity stress.

    Science.gov (United States)

    Gao, Xiang; Cao, Donghui; Liu, Jie; Wang, Xiaoping; Geng, Shujuan; Liu, Bao; Shi, Decheng

    2013-01-01

    Salinity is a widespread environmental problem limiting productivity and growth of plants. Halophytes which can adapt and resist certain salt stress have various mechanisms to defend the higher salinity and alkalinity, and epigenetic mechanisms especially DNA methylation may play important roles in plant adaptability and plasticity. In this study, we aimed to investigate the different influences of various single salts (NaCl, Na2SO4, NaHCO3, Na2CO3) and their mixed salts on halophyte Chloris. virgata from the DNA methylation prospective, and discover the underlying relationships between specific DNA methylation variations and specific cations/anions through the methylation-sensitive amplification polymorphism analysis. The results showed that the effects on DNA methylation variations of single salts were ranked as follows: Na2CO3> NaHCO3> Na2SO4> NaCl, and their mixed salts exerted tissue-specific effects on C. virgata seedlings. Eight types of DNA methylation variations were detected and defined in C. virgata according to the specific cations/anions existed in stressful solutions; in addition, mix-specific and higher pH-specific bands were the main type in leaves and roots independently. These findings suggested that mixed salts were not the simple combination of single salts. Furthermore, not only single salts but also mixed salts showed tissue-specific and cations/anions-specific DNA methylation variations.

  15. Acid-base balance in rainbow trout (Salmo gairdneri) subjected to acid stresses

    Energy Technology Data Exchange (ETDEWEB)

    Eddy, F.B.

    1976-01-01

    The respiratory properties of rainbow-trout blood were investigated in acid-stressed fish. In the first group acid was introduced into the bloodstream and in the second the carbon dioxide content of the ambient water was increased. Initially the introduction of the acid to the blood caused a decrease in blood pH and bicarbonate, and increases in oxygen uptake and ventilation volume. After 2 to 3 h these values had returned to the control levels. Trout subjected to high ambient CO/sub 2/ (about 10 mmHg) showed a decrease in blood pH while PCO/sub 2/ and bicarbonate increased. After 8 h the trout began to show signs of compensation to the acidosis. In each experiment the blood PO/sub 2/ was little changed but blood O/sub 2/ content was decreased and tended not to resume the control value even after several hours. The results are discussed in terms of the various acid-base mechanisms thought to be available to the fish. These include branchial ion exchanges and the possible buffering roles of the extracellular and intracellular fluids.

  16. Effect of Protectants on the Fermentation Performance of Wine Yeasts Subjected to Osmotic Stress

    Directory of Open Access Journals (Sweden)

    Andrea Caridi

    2003-01-01

    Full Text Available During alcoholic fermentation of must from dried grapes, yeasts are subjected to very high sugar concentrations, besides other environmental stresses, and they modify their metabolic behaviour giving low ethanol yield and abnormally high acetic acid production. To investigate the protective effect of catechin, inositol, and SO2 on wine yeasts, three thermotolerant strains of Saccharomyces cerevisiae, selected for wine making of must from dried grapes, and three strains of Saccharomyces selected for the production of wine, were inoculated in a sample of must at very high osmotic strength. A significant (p<0.01 or p<0.05 relationship between the addition of 100 mg/L of catechin, inositol or SO2 to the grape must and the change in the metabolic behaviour of the yeasts was observed. Compared to the control and depending on strain and protectant, the fermentation rate after 3 days increased up to 55 %, the ethanol content of the wines increased up to 16 %, the unitary succinic acid production increased up to 55 %, the unitary acetic acid production decreased up to 53 %, and the unitary glycerol production decreased up to 69 %. So by adding catechin, inositol or SO2 to the grape must it is possible to minimise the abnormal fermentation performance that wine yeasts exhibit in wine making of must from dried grapes.

  17. Symptoms and subjective quality of life in post-traumatic stress disorder: a longitudinal study.

    Science.gov (United States)

    Giacco, Domenico; Matanov, Aleksandra; Priebe, Stefan

    2013-01-01

    Evidence suggests that post-traumatic stress disorder (PTSD) is associated with substantially reduced subjective quality of life (SQOL). This study aimed to explore whether and how changes in the levels of PTSD symptom clusters of intrusion, avoidance and hyperarousal are associated with changes in SQOL. Two samples with PTSD following the war in former Yugoslavia were studied, i.e. a representative sample of 530 people in five Balkan countries and a non-representative sample of 215 refugees in three Western European countries. They were assessed on average eight years after the war and re-interviewed one year later. PTSD symptoms were assessed on the Impact of Event Scale - Revised and SQOL on the Manchester Short Assessment of Quality of Life. Linear regression and a two-wave cross lagged panel analysis were used to explore the association between PTSD symptom clusters and SQOL. The findings in the two samples were consistent. Symptom reduction over time was associated with improved SQOL. In multivariable analyses adjusted for the influence of all three clusters, gender and time since war exposure, only changes in hyperarousal symptoms were significantly associated with changes in SQOL. The two-wave cross-lagged panel analysis suggested that the link between hyperarousal symptoms and SQOL is bidirectional. Low SQOL of patients with war-related PTSD is particularly associated with hyperarousal symptoms. The findings suggest a bidirectional influence: a reduction in hyperarousal symptoms may result in improved SQOL, and improvements in SQOL may lead to reduced hyperarousal symptoms.

  18. Creep and creep recovery of concrete subjected to triaxial compressive stresses at elevated temperature

    International Nuclear Information System (INIS)

    Ohnuma, Hiroshi; Abe, Hirotoshi

    1979-01-01

    In order to design rationally the vessels made of prestressed concrete for nuclear power stations and to improve the accuracy of high temperature creep analysis, the Central Research Institute of Electric Power Industry had carried out the proving experiments with scale models. In order to improve the accuracy of analysis, it is important to grasp the creep behavior of the concrete subjected to triaxial compressive stresses at high temperature as the basic property of concrete, because actual prestressed concrete vessels are in such conditions. In this paper, the triaxial compression creep test at 60 deg. C using the concrete specimens with same mixing ratio as the scale models is reported. The compressive strength of the concrete at the age of 28 days was 406 kg/cm 2 , and the age of the concrete at the time of loading was 63 days. Creep and creep recovery were measured for 5 months and 2 months, respectively. The creep of concrete due to uniaxial compression increased with temperature rise, and the creep strain at 60 deg. C was 2.54 times as much as that at 20 deg. C. The effective Poisson's ratio in triaxial compression creep was 0.15 on the average, based on the creep strain due to uniaxial compression at 60 deg. C. The creep recovery rate in high temperature, triaxial compression creep was 33% on the average. (Kako, I.)

  19. Seed viability of Dimorphandra gardneriana subject to water stress in different temperatures

    Directory of Open Access Journals (Sweden)

    Marina Matias Ursulino

    Full Text Available ABSTRACT: The forest species Dimorphandra gardneriana Tul. is widely used for various pharmacological products, yet few basic studies have been undertaken to understand their ecological and physiological attributes under stress conditions. The goal of this research was to evaluate the seed germination and vigor when subjected to different osmotic potentials and temperatures. Water restriction was simulated with polyethylene glycol 6000 solution (PEG 6000 with osmotic potentials of 0; -0,2; -0,4; -0,6; -0,8, and -1,0MPa at temperatures of 20, 25, 30, and 35°C. The effect of the treatment was determined by the germination and vigor (germination speed index, length and phytomass of dry shoot and roots of the seeds, in an entirely random design with four repetitions. From-0, 4MPa it occurs a drastic reduction in germination and vigor of seeds although these factors were less affected at temperature of 25°C up to -0, 2MPa.

  20. Validity of multiple stress creep recovery test for LADOTD asphalt binder specification.

    Science.gov (United States)

    2010-09-01

    The objectives of this research are to characterize the elastic response of various binders used by LADOTD to determine the feasibility of the Multiple Stress Creep Recovery (MSCR) test to be included in the LADOTD asphalt binder specification and to...

  1. Pregnancy-specific stress, preterm birth, and gestational age among high-risk young women.

    Science.gov (United States)

    Cole-Lewis, Heather J; Kershaw, Trace S; Earnshaw, Valerie A; Yonkers, Kimberly Ann; Lin, Haiqun; Ickovics, Jeannette R

    2014-09-01

    There is evidence that pregnancy-specific stress is associated with preterm birth. The purpose of this study is to examine the association between change in pregnancy-specific stress over the course of pregnancy and birth outcomes (i.e., preterm birth and gestational age) in an understudied but vulnerable group using a theoretically derived model. Multivariate linear and logistic regression techniques were used to examine the association between pregnancy-specific stress (measured in second and third trimester) and length of gestation (i.e., preterm birth and gestational age) among a sample of 920 Black and/or Latina adolescent and young women. Second trimester pregnancy-specific stress was not associated with preterm birth or gestational age. Third trimester pregnancy-specific stress was associated with preterm birth but not with gestational age. Change in pregnancy-specific stress between second and third trimester was significantly associated with increased likelihood of preterm delivery and shortened gestational age, even after controlling for important biological, behavioral, psychological, interpersonal, and sociocultural risk factors. Findings emphasize the importance of measuring pregnancy-specific stress across pregnancy, as the longitudinal change from second to third trimester was significantly associated with length of gestation measured both as a dichotomous variable (preterm birth) and a continuous variable (gestational age). Furthermore, this is the first study to observe the association of pregnancy-specific stress with length of gestation in this understudied population-unique in age, race, and ethnicity. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  2. Transcriptome analysis and identification of significantly differentially expressed genes in Holstein calves subjected to severe thermal stress

    Science.gov (United States)

    Srikanth, Krishnamoorthy; Lee, Eunjin; Kwan, Anam; Lim, Youngjo; Lee, Junyep; Jang, Gulwon; Chung, Hoyoung

    2017-11-01

    RNA-Seq analysis was used to characterize transcriptome response of Holstein calves to thermal stress. A total of eight animals aged between 2 and 3 months were randomly selected and subjected to thermal stress corresponding to a temperature humidity index of 95 in an environmentally controlled house for 12 h consecutively for 3 days. A set of 15,787 unigenes were found to be expressed and after a threshold of threefold change, and a Q value physiological and metabolic processes to survive. Many of the genes identified in this study have not been previously reported to be involved in thermal stress response. The results of this study extend our understanding of the animal's response to thermal stress and some of the identified genes may prove useful in the efforts to breed Holstein cattle with superior thermotolerance, which might help in minimizing production loss due to thermal stress.

  3. Comparative proteome analysis of metabolic proteins from seeds of durum wheat (cv. Svevo) subjected to heat stress

    DEFF Research Database (Denmark)

    Laino, Paolo; Shelton, Dale; Finnie, Christine

    2010-01-01

    of nonprolamin proteins were monitored to identify polypeptides affected by heat stress during grain fill. This study shows that heat stress alters significantly the durum wheat seed proteome, although the changes range is only between 1.2- and 2.2-fold. This analysis revealed 132 differentially expressed...... include proteins with metabolic activity or structural function. In order to investigate the consequences of heat stress on the accumulation of nonprolamin proteins in mature durum wheat kernels, the Italian cultivar Svevo was subjected to two thermal regimes (heat stress versus control). The 2-D patterns...... polypeptides, 47 of which were identified by MALDI-TOF and MALDI-TOF-TOF MS and included HSPs, proteins involved in the glycolysis and carbohydrate metabolism, as well as stress-related proteins. Many of the heat-induced polypeptides are considered to be allergenic for sensitive individuals....

  4. Specific microRNAs Regulate Heat Stress Responses in Caenorhabditis elegans

    DEFF Research Database (Denmark)

    Nehammer, Camilla; Podolska, Agnieszka; Mackowiak, Sebastian D

    2015-01-01

    have identified additional functions for already known players (mir-71 and mir-239) as well as identifying mir-80 and the mir-229 mir-64-66 cluster as important regulators of the heat stress response in C. elegans. These findings uncover an additional layer of complexity to the regulation of stress...... to heat stress in Caenorhabditis elegans and show that a discrete subset of miRNAs is thermoregulated. Using in-depth phenotypic analyses of miRNA deletion mutant strains we reveal multiple developmental and post-developmental survival and behavioral functions for specific miRNAs during heat stress. We...

  5. Ventromedial Frontal Lobe Damage Alters how Specific Attributes are Weighed in Subjective Valuation.

    Science.gov (United States)

    Vaidya, Avinash R; Sefranek, Marcus; Fellows, Lesley K

    2017-10-23

    The concept of subjective value is central to current neurobiological views of economic decision-making. Much of this work has focused on signals in the ventromedial frontal lobe (VMF) that correlate with the subjective value of a variety of stimuli (e.g., food, monetary gambles), and are thought to support decision-making. However, the neural processes involved in assessing and integrating value information from the attributes of such complex options remain to be defined. Here, we tested the necessary role of VMF in weighting attributes of naturalistic stimuli during value judgments. We asked how distinct attributes of visual artworks influenced the subjective value ratings of subjects with VMF damage, compared to healthy participants and a frontal lobe damaged control group. Subjects with VMF damage were less influenced by the energy (emotion, complexity) and color radiance (warmth, saturation) of the artwork, while they were similar to control groups in considering saliency, balance and concreteness. These dissociations argue that VMF is critical for allowing certain affective content to influence subjective value, while sparing the influence of perceptual or representational information. These distinctions are important for better defining the often-underspecified concept of subjective value and developing more detailed models of the brain mechanisms underlying decision behavior. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  6. PENGEMBANGAN SUBJECT SPECIFIC PEDAGOGY (SSP IPA TERPADU UNTUK MENINGKATKAN HASIL BELAJAR SISWA

    Directory of Open Access Journals (Sweden)

    Fitri Yuliawati

    2016-05-01

    Full Text Available Background of this research is the analysis of the results of interviews some junior secondary schools in Yogyakarta and the conclusion that teachers do not use an integrated science teaching and teachers still find difficulties in the application of learning science in an integrated manner. It can be influenced by several factors, such as the lack of reference used by teachers in presenting the material Integrated Science relevantly, most of science teachers are from educational background of chemistry, physics, and biology instead of science education, so that teachers find difficulties to create an integrated learning of science. In addition, teachers feel difficulty in determining the depth of the material, limits of integration in integrated science teaching, and did not know the concept of integrated science teaching. This research is a development research. Learning tools developed included : student books, lesson plans, student activity sheets and evaluation tools. The development of the learning which is done in this study use the models of 4D development which includes the step of Define (definition which at this stage conducted a needs analysis. Design : it is the stage of Subject Specific Pedagogy (SSP software design. Development, it is the stage of development after the draft was made followed by a learning device validation by experts. This stage is also conducted to seek input from all the responses, reactions and comments from teachers, students, and observers so that it can be used for further improvement of science teaching later. The Disseminate, it is the stage of field tests are widely but not done. Data collection instruments used in this study include : test items and questionnaire. The conclusion of this development research are as follows : the results of the validation SSP integrated science by learning tools expert, material experts and media experts indicate the category of Very Good (SB so that SSP integrated

  7. Subject-specific regional measures of water diffusion are associated with impairment in chronic spinal cord injury.

    Science.gov (United States)

    Choe, Ann S; Sadowsky, Cristina L; Smith, Seth A; van Zijl, Peter C M; Pekar, James J; Belegu, Visar

    2017-08-01

    We aimed to identify non-invasive imaging parameters that can serve as biomarkers for the integrity of the spinal cord, which is paramount to neurological function. Diffusion tensor imaging (DTI) indices are sensitive to axonal and myelin damage, and have strong potential to serve as such biomarkers. However, averaging DTI indices over large regions of interest (ROIs), a common approach to analyzing the images of injured spinal cord, leads to loss of subject-specific information. We investigated if DTI-tractography-driven, subject-specific demarcation approach can yield measures that are more specific to impairment. In 18 individuals with chronic spinal cord injury (SCI), subject-specific demarcation of the injury region was performed using DTI tractography, which yielded three regions relative to injury (RRI; regions superior to, at, and below injury epicenter). DTI indices averaged over each RRI were correlated with measures of residual motor and sensory function, obtained using the International Standard of Neurological Classification for Spinal Cord Injury (ISNCSCI). Total ISNCSCI score (ISNCSCI-tot; sum of ISNCSCI motor and sensory scores) was significantly (p injury epicenter (IRRI), the degree of which exceeded that of those measured from the entire cervical cord-suggesting contribution from Wallerian degeneration. DTI tractography-driven, subject-specific injury demarcation approach provided measures that were more specific to impairment. Notably, DTI indices obtained from the IRRI region showed the highest specificity to impairment, demonstrating their strong potential as biomarkers for the SCI severity.

  8. Validating atlas-guided DOT: a comparison of diffuse optical tomography informed by atlas and subject-specific anatomies.

    Science.gov (United States)

    Cooper, Robert J; Caffini, Matteo; Dubb, Jay; Fang, Qianqian; Custo, Anna; Tsuzuki, Daisuke; Fischl, Bruce; Wells, William; Dan, Ippeita; Boas, David A

    2012-09-01

    We describe the validation of an anatomical brain atlas approach to the analysis of diffuse optical tomography (DOT). Using MRI data from 32 subjects, we compare the diffuse optical images of simulated cortical activation reconstructed using a registered atlas with those obtained using a subject's true anatomy. The error in localization of the simulated cortical activations when using a registered atlas is due to a combination of imperfect registration, anatomical differences between atlas and subject anatomies and the localization error associated with diffuse optical image reconstruction. When using a subject-specific MRI, any localization error is due to diffuse optical image reconstruction only. In this study we determine that using a registered anatomical brain atlas results in an average localization error of approximately 18 mm in Euclidean space. The corresponding error when the subject's own MRI is employed is 9.1 mm. In general, the cost of using atlas-guided DOT in place of subject-specific MRI-guided DOT is a doubling of the localization error. Our results show that despite this increase in error, reasonable anatomical localization is achievable even in cases where the subject-specific anatomy is unavailable. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. Stressor specificity of central neuroendocrine responses: implications for stress-related disorders.

    Science.gov (United States)

    Pacák, K; Palkovits, M

    2001-08-01

    Despite the fact that many research articles have been written about stress and stress-related diseases, no scientifically accepted definition of stress exists. Selye introduced and popularized stress as a medical and scientific idea. He did not deny the existence of stressor-specific response patterns; however, he emphasized that such responses did not constitute stress, only the shared nonspecific component. In this review we focus mainly on the similarities and differences between the neuroendocrine responses (especially the sympathoadrenal and the sympathoneuronal systems and the hypothalamo-pituitary-adrenocortical axis) among various stressors and a strategy for testing Selye's doctrine of nonspecificity. In our experiments, we used five different stressors: immobilization, hemorrhage, cold exposure, pain, or hypoglycemia. With the exception of immobilization stress, these stressors also differed in their intensities. Our results showed marked heterogeneity of neuroendocrine responses to various stressors and that each stressor has a neurochemical "signature." By examining changes of Fos immunoreactivity in various brain regions upon exposure to different stressors, we also attempted to map central stressor-specific neuroendocrine pathways. We believe the existence of stressor-specific pathways and circuits is a clear step forward in the study of the pathogenesis of stress-related disorders and their proper treatment. Finally, we define stress as a state of threatened homeostasis (physical or perceived treat to homeostasis). During stress, an adaptive compensatory specific response of the organism is activated to sustain homeostasis. The adaptive response reflects the activation of specific central circuits and is genetically and constitutionally programmed and constantly modulated by environmental factors.

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

    Science.gov (United States)

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

    2017-12-01

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

  11. Glial and tissue-specific regulation of Kynurenine Pathway dioxygenases by acute stress of mice

    Directory of Open Access Journals (Sweden)

    Carlos R. Dostal

    2017-12-01

    Full Text Available Stressors activate the hypothalamic-pituitary-adrenal (HPA axis and immune system eliciting changes in cognitive function, mood and anxiety. An important link between stress and altered behavior is stimulation of the Kynurenine Pathway which generates neuroactive and immunomodulatory kynurenines. Tryptophan entry into this pathway is controlled by rate-limiting indoleamine/tryptophan 2,3-dioxygenases (DOs: Ido1, Ido2, Tdo2. Although implicated as mediating changes in behavior, detecting stress-induced DO expression has proven inconsistent. Thus, C57BL/6J mice were used to characterize DO expression in brain-regions, astrocytes and microglia to characterize restraint-stress-induced DO expression. Stress increased kynurenine in brain and plasma, demonstrating increased DO activity. Of three Ido1 transcripts, only Ido1-v1 expression was increased by stress and within astrocytes, not microglia, indicating transcript- and glial-specificity. Stress increased Ido1-v1 only in frontal cortex and hypothalamus, indicating brain-region specificity. Of eight Ido2 transcripts, Ido2-v3 expression was increased by stress, again only within astrocytes. Likewise, stress increased Tdo2-FL expression in astrocytes, not microglia. Interestingly, Ido2 and Tdo2 transcripts were not correspondingly induced in Ido1-knockout (Ido1KO mice, suggesting that Ido1 is necessary for the central DO response to acute stress. Unlike acute inflammatory models resulting in DO induction within microglia, only astrocyte DO expression was increased by acute restraint-stress, defining their unique role during stress-dependent activation of the Kynurenine Pathway. Keywords: Stress, Ido, Tdo, Kynurenine, Astrocyte, Liver

  12. Subjective happiness among mothers of children with disabilities: The role of stress, attachment, guilt and social support.

    Science.gov (United States)

    Findler, Liora; Klein Jacoby, Ayelet; Gabis, Lidia

    2016-08-01

    Parenting a child with disabilities might affect the happiness of the mothers. Hence we adapted Wallander, Varni, Babani, Banis, and Wilcox's (1989) disability-stress-coping model to examine the impact of risk factors (specific stressors related to the child's disability) on the mother's adaptation (happiness). Intrapersonal factors (attachment) and social-ecological factors (social support) were hypothesized to predict adaptation. Both constitute 'risk-resistant' factors, which are mediated by the mother's perceived general stress and guilt. 191 mothers of a child with a developmental disability (ages 3-7) answered questionnaires on happiness, specific and general stress, attachment, guilt and social support. Attachment avoidance was directly and negatively associated with mothers' happiness. General stress was negatively associated with happiness, and mediated the association between anxious attachment, support, and specific stress with happiness. Guilt was negatively associated with happiness, and served as a mediator between attachment anxiety and support and happiness. The findings of the current research show direct and indirect associations of risk factors with happiness and the role of general stress and feelings of guilt as mediators. This study stresses the importance of attachment and social support to happiness and sheds light on the unique role of guilt in promoting or inhibiting happiness. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Symptoms and subjective quality of life in post-traumatic stress disorder: a longitudinal study.

    Directory of Open Access Journals (Sweden)

    Domenico Giacco

    Full Text Available BACKGROUND: Evidence suggests that post-traumatic stress disorder (PTSD is associated with substantially reduced subjective quality of life (SQOL. This study aimed to explore whether and how changes in the levels of PTSD symptom clusters of intrusion, avoidance and hyperarousal are associated with changes in SQOL. METHODS: Two samples with PTSD following the war in former Yugoslavia were studied, i.e. a representative sample of 530 people in five Balkan countries and a non-representative sample of 215 refugees in three Western European countries. They were assessed on average eight years after the war and re-interviewed one year later. PTSD symptoms were assessed on the Impact of Event Scale - Revised and SQOL on the Manchester Short Assessment of Quality of Life. Linear regression and a two-wave cross lagged panel analysis were used to explore the association between PTSD symptom clusters and SQOL. RESULTS: The findings in the two samples were consistent. Symptom reduction over time was associated with improved SQOL. In multivariable analyses adjusted for the influence of all three clusters, gender and time since war exposure, only changes in hyperarousal symptoms were significantly associated with changes in SQOL. The two-wave cross-lagged panel analysis suggested that the link between hyperarousal symptoms and SQOL is bidirectional. CONCLUSIONS: Low SQOL of patients with war-related PTSD is particularly associated with hyperarousal symptoms. The findings suggest a bidirectional influence: a reduction in hyperarousal symptoms may result in improved SQOL, and improvements in SQOL may lead to reduced hyperarousal symptoms.

  14. Cortical surface area reduction in identification of subjects at high risk for post-traumatic stress disorder: A pilot study.

    Science.gov (United States)

    Hu, Hao; Sun, Yawen; Su, Shanshan; Wang, Yao; Qiu, Yongming; Yang, Xi; Zhou, Yan; Xiao, Zeping; Wang, Zhen

    2018-01-01

    Victims of motor vehicle accidents often develop post-traumatic stress disorder, which causes significant social function loss. For the difficulty in treating post-traumatic stress disorder, identification of subjects at high risk for post-traumatic stress disorder is essential for providing possible intervention. This paper aims to examine the cortical structural traits related to susceptibility to post-traumatic stress disorder. To address this issue, we performed structural magnetic resonance imaging study in motor vehicle accident victims within 48 hours from the accidents. A total of 70 victims, available for both clinical and magnetic resonance imaging data, enrolled in our study. Upon completion of 6-month follow-up, 29 of them developed post-traumatic stress disorder, while 41 of them didn't. At baseline, voxelwise comparisons of cortical thickness, cortical area and cortical volume were conducted between post-traumatic stress disorder group and trauma control group. As expected, several reduced cortical volume within frontal-temporal loop were observed in post-traumatic stress disorder. For cortical thickness, no between-group differences were observed. There were three clusters in left hemisphere and one cluster in right hemisphere showing decreased cortical area in post-traumatic stress disorder patients, compared with trauma controls. Peak voxels of the three clusters in left hemisphere were separately located in superior parietal cortex, insula and rostral anterior cingulate cortex. The finding of reduced surface area of left insula and left rostral anterior cingulate cortex suggests that shrinked surface area in motor vehicle accident victims could act as potential biomarker of subjects at high risk for post-traumatic stress disorder.

  15. Stress concentration factors for integral and pad reinforced nozzles in spherical pressure vessels subjected to radial load and moment

    International Nuclear Information System (INIS)

    Soliman, S.F.; Gill, S.S.

    1979-01-01

    Charts are presented giving the elastic stress concentration factors in spherical pressure vessels with pad and integral reinforcement for radial branches subjected to radial load and moment. The effect of all the geometrical parameters is discussed, including the limitations of thin shell theory on the validity of the results. (author)

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

    Science.gov (United States)

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

    2014-10-01

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

  17. Presence of a dog reduces subjective but not physiological stress responses to an analog trauma

    OpenAIRE

    Lass-Hennemann, Johanna; Peyk, Peter; Streb, Markus; Holz, Elena; Michael, Tanja

    2014-01-01

    Dogs are known to have stress and anxiety reducing effects. Several studies have shown that dogs are able to calm people during cognitive and performance stressors. Recently, therapy dogs have been proposed as a treatment adjunct for post-traumatic stress disorder patients. In this study we aimed to investigate, whether dogs also have anxiety- and stress reducing effect during “traumatic stressors.” 80 healthy female participants were randomly assigned to one of four conditions. They were exp...

  18. Stress management interventions: Improving subjective psychological well-being in the workplace

    OpenAIRE

    Holman, David; Johnson, Sheena; O'Connor, Elinor

    2018-01-01

    In this chapter we provide an overview of stress management interventions (SMI) and review the evidence for their effects on employee stress and well-being. We start by setting out a typology of SMI that classes SMI according to level (i.e., the individual-level or organisation-level) and focus (i.e., a ‘primary’ focus on altering the causes of stress or a ‘secondary’ or ‘tertiary’ focus on reducing stress itself). We then use this typology to describe key types of SMI, after which we review ...

  19. Prenatal stress challenge impairs fetal lung development and asthma severity sex-specifically in mice.

    Science.gov (United States)

    Zazara, Dimitra E; Perani, Clara V; Solano, María E; Arck, Petra C

    2018-02-01

    Allergic asthma is an increasing health problem worldwide. Interestingly, prenatal challenges such as stress have been associated with an increased risk for asthma during childhood. The underlying pathogenesis of how prenatal stress increases the risk for asthma still remains unclear. Potential targets could be that the fetal immune ontogeny or fetal lung development are compromised by prenatal challenges. Here, we aimed to identify whether prenatal stress challenge affects fetal lung development in mice. C57BL/6 pregnant mice were challenged with sound stress and fetal lung development was assessed histologically. Whilst prenatal stress challenge did not profoundly affect lung development in male fetuses, it resulted in less extensive terminal sacs, surrounded by thicker mesenchymal tissue in female fetuses. Thus, prenatal stress disrupted fetal lung development sex-specifically. Interestingly, upon prenatal stress challenge, the airway hyperresponsiveness and eosinophilic inflammation- two hallmarks of asthma - were significantly increased in adult female offspring, whilst regulatory CD4+ T cells were reduced. These findings strongly underpin the sex-specific association between s challenged fetal development and a sex-specific altered severity of asthma in adult offspring. Our model now allows to identify maternal markers through which the risk for asthma and possible other diseases is vertically transferred before birth in response to challenges. Such identification then opens avenues for primary disease prevention. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Occupational stress and its association with early retirement and subjective need for occupational rehabilitation in cancer patients.

    Science.gov (United States)

    Böttcher, Hilke M; Steimann, Monika; Rotsch, Martin; Zurborn, Karl-Heinz; Koch, Uwe; Bergelt, Corinna

    2013-08-01

    Returning to work often plays an important role for cancer survivors. Occupational stress may hamper a successful return to work, so cancer survivors should be given the opportunity to address occupational stress issues before returning to work. We investigated the amount of occupational stress among cancer patients and whether it is associated with their well-being, their subjective need for occupational rehabilitation and elevations in their risk of early retirement. At the beginning of rehabilitation, we asked cancer patients to respond to occupation-related and health-related questionnaires. We used t-tests, chi-square tests, and logistic regression analyses to address our research questions. A total of 477 patients participated in the study. Of these, 19% were occupationally stressed, and 26% reported subjective need for occupational rehabilitation. Patients who reported work-related stress had a diminished quality of life, were more likely to report subjective need for occupational rehabilitation (OR = 2.16), and had a higher risk of early retirement (OR = 5.44). Furthermore, cancer patients reported deficits in both active coping abilities and mental stability at work. Because occupational stress is associated with a higher risk of early retirement, both patients and physicians should take work-related problems seriously. Screening patients for occupational stress may help physicians identify patients who are at risk of experiencing problematic work re-entries. Furthermore, the results of the study suggest that cancer patients might have problems maintaining confidence in their abilities to solve work-related problems. Therefore, facilitating the development of a perception of self-efficacy might be an important treatment goal. Copyright © 2012 John Wiley & Sons, Ltd.

  1. Oxidative stress in patients with endemic pemphigus foliaceus and healthy subjects with anti-desmoglein 1 antibodies*

    Science.gov (United States)

    Gutierrez, Ericson Leonardo; Ramos, Willy; Seminario-Vidal, Lucia; Tello, Mercedes; Ronceros, Gerardo; Ortega-Loayza, Alex G.

    2018-01-01

    Background Previous studies have shown oxidative stress in pemphigus vulgaris and pemphigus foliaceus, nevertheless, it remains unknown whether a similar response is characteristic of endemic pemphigus foliaceus in Peru. Objectives To determine the oxidative stress response in endemic pemphigus foliaceus patients and subjects with positive for anti-desmoglein1 antibodies (anti-dsg1) from endemic areas of Peru. Subjects and Methods This is a cross-sectional study. The study population included 21 patients with Endemic Pemphigus foliaceus and 12 healthy subjects with anti-dsg1 antibodies from the Peruvian Amazon (Ucayali), as well as 30 healthy control subjects. Malondialdehyde, an indicator of lipid peroxidation by free radicals, was measured in serum. Results We collected 21 cases of endemic pemphigus foliaceus, 15 of them with active chronic disease and 6 in clinical remission. Serum malondialdehyde values in patients with chronic active evolution and healthy subjects with anti-dsg1 antibodies were statistically higher than those of healthy controls (p<0.001). There was no significant difference between serum values of localized and generalized clinical forms. Study limitations The main limitation of this present study is the small number of patients with endemic pemphigus and healthy subjects positive for desmoglein 1 antibodies. Conclusions The increased serum levels of malondialdehyde in patients with chronic active endemic pemphigus foliaceus and healthy subjects from endemic areas with anti-dsg1 antibodies may suggest a contribution of systemic lipid peroxidation in the pathogenesis of endemic pemphigus foliaceus. PMID:29723379

  2. Sex-Specificity of Oxidative Stress in Newborns Leading to a Personalized Antioxidant Nutritive Strategy

    Directory of Open Access Journals (Sweden)

    Jean-Claude Lavoie

    2018-03-01

    Full Text Available Oxidative stress is a critical process that triggers several diseases observed in premature infants. Growing recognition of the detriment of oxidative stress in newborns warrants the use of an antioxidant strategy that is likely to be nutritional in order to restore redox homeostasis. It appears essential to have a personalized approach that will take into account the age of gestation at birth and the sex of the infant. However, the link between sex and oxidative stress remains unclear. The aim of this study was to find a common denominator explaining the discrepancy between studies related to sex-specific effects of oxidative stress. Results highlight a specificity of sex in the levels of oxidative stress markers linked to the metabolism of glutathione, as measured in the intracellular compartments. Levels of all sex-dependent oxidative stress markers are greater and markers associated to a better antioxidant defense are lower in boys compared to girls during the neonatal period. This sex-specific discrepancy is likely to be related to estrogen metabolism, which is more active in baby-girls and promotes the activation of glutathione metabolism. Conclusion: our observations suggest that nutritive antioxidant strategies need to target glutathione metabolism and, therefore, should be personalized considering, among others, the sex specificity.

  3. Sex-Specificity of Oxidative Stress in Newborns Leading to a Personalized Antioxidant Nutritive Strategy.

    Science.gov (United States)

    Lavoie, Jean-Claude; Tremblay, André

    2018-03-27

    Oxidative stress is a critical process that triggers several diseases observed in premature infants. Growing recognition of the detriment of oxidative stress in newborns warrants the use of an antioxidant strategy that is likely to be nutritional in order to restore redox homeostasis. It appears essential to have a personalized approach that will take into account the age of gestation at birth and the sex of the infant. However, the link between sex and oxidative stress remains unclear. The aim of this study was to find a common denominator explaining the discrepancy between studies related to sex-specific effects of oxidative stress. Results highlight a specificity of sex in the levels of oxidative stress markers linked to the metabolism of glutathione, as measured in the intracellular compartments. Levels of all sex-dependent oxidative stress markers are greater and markers associated to a better antioxidant defense are lower in boys compared to girls during the neonatal period. This sex-specific discrepancy is likely to be related to estrogen metabolism, which is more active in baby-girls and promotes the activation of glutathione metabolism. our observations suggest that nutritive antioxidant strategies need to target glutathione metabolism and, therefore, should be personalized considering, among others, the sex specificity.

  4. Experimental Investigation of Subject-Specific On-Body Radio Propagation Channels for Body-Centric Wireless Communications

    Directory of Open Access Journals (Sweden)

    Mohammad Monirujjaman Khan

    2014-01-01

    Full Text Available In this paper, subject-specific narrowband (2.45 GHz and ultra-wideband (3–10.6 GHz on-body radio propagation studies in wireless body area networks (WBANs were performed by characterizing the path loss for eight different human subjects of different shapes and sizes. The body shapes and sizes of the test subjects used in this study are characterised as thin, medium build, fatty, shorter, average height and taller. Experimental investigation was made in an indoor environment using a pair of printed monopoles (for the narrowband case and a pair of tapered slot antennas (for the ultra-wideband (UWB case. Results demonstrated that, due to the different sizes, heights and shapes of the test subjects, the path loss exponent value varies up to maximum of 0.85 for the narrowband on-body case, whereas a maximum variation of the path loss exponent value of 1.15 is noticed for the UWB case. In addition, the subject-specific behaviour of the on-body radio propagation channels was compared between narrowband and UWB systems, and it was deduced that the on-body radio channels are subject-specific for both narrowband and UWB system cases, when the same antennas (same characteristics are used. The effect of the human body shape and size variations on the eight different on-body radio channels is also studied for both the narrowband and UWB cases.

  5. Arabidopsis non-specific phospholipase C1: Characterization and its involvement in response to heat stress

    Czech Academy of Sciences Publication Activity Database

    Krčková, Zuzana; Brouzdová, Jitka; Daněk, Michal; Kocourková, Daniela; Rainteau, D.; Ruelland, E.; Valentová, O.; Pejchar, Přemysl; Martinec, Jan

    2015-01-01

    Roč. 6, NOV 4 (2015), s. 928 ISSN 1664-462X R&D Projects: GA ČR(CZ) GAP501/12/1942 Institutional support: RVO:61389030 Keywords : Arabidopsis thaliana * Diacylglycerol * Heat stress Subject RIV: ED - Physiology Impact factor: 4.495, year: 2015

  6. Stress-intensity factor equations for cracks in three-dimensional finite bodies subjected to tension and bending loads

    Science.gov (United States)

    Newman, J. C., Jr.; Raju, I. S.

    1984-01-01

    Stress intensity factor equations are presented for an embedded elliptical crack, a semielliptical surface crack, a quarter elliptical corner crack, a semielliptical surface crack along the bore of a circular hole, and a quarter elliptical corner crack at the edge of a circular hole in finite plates. The plates were subjected to either remote tension or bending loads. The stress intensity factors used to develop these equations were obtained from previous three dimensional finite element analyses of these crack configurations. The equations give stress intensity factors as a function of parametric angle, crack depth, crack length, plate thickness, and, where applicable, hole radius. The ratio of crack depth to plate thickness ranged from 0 to 1, the ratio of crack depth to crack length ranged from 0.2 to 2, and the ratio of hole radius to plate thickness ranged from 0.5 to 2. The effects of plate width on stress intensity variation along the crack front were also included.

  7. Carotenoid profiling of leaves of selected eggplant accessions subjected to drought stress

    Science.gov (United States)

    This study focused on the quantification of carotenoids of the leaves of African eggplants commonly consumed as leafy and fruit vegetables. The results gave comparative profiles of carotenoids at different growth and developmental stages and under drought stress. Stress was achieved by limiting irri...

  8. Encoding negative events under stress: high subjective arousal is related to accurate emotional memory despite misinformation exposure.

    Science.gov (United States)

    Hoscheidt, Siobhan M; LaBar, Kevin S; Ryan, Lee; Jacobs, W Jake; Nadel, Lynn

    2014-07-01

    Stress at encoding affects memory processes, typically enhancing, or preserving, memory for emotional information. These effects have interesting implications for eyewitness accounts, which in real-world contexts typically involve encoding an aversive event under stressful conditions followed by potential exposure to misinformation. The present study investigated memory for a negative event encoded under stress and subsequent misinformation endorsement. Healthy young adults participated in a between-groups design with three experimental sessions conducted 48 h apart. Session one consisted of a psychosocial stress induction (or control task) followed by incidental encoding of a negative slideshow. During session two, participants were asked questions about the slideshow, during which a random subgroup was exposed to misinformation. Memory for the slideshow was tested during the third session. Assessment of memory accuracy across stress and no-stress groups revealed that stress induced just prior to encoding led to significantly better memory for the slideshow overall. The classic misinformation effect was also observed - participants exposed to misinformation were significantly more likely to endorse false information during memory testing. In the stress group, however, memory accuracy and misinformation effects were moderated by arousal experienced during encoding of the negative event. Misinformed-stress group participants who reported that the negative slideshow elicited high arousal during encoding were less likely to endorse misinformation for the most aversive phase of the story. Furthermore, these individuals showed better memory for components of the aversive slideshow phase that had been directly misinformed. Results from the current study provide evidence that stress and high subjective arousal elicited by a negative event act concomitantly during encoding to enhance emotional memory such that the most aversive aspects of the event are well remembered and

  9. Numerical simulation of mechanisms of deformation,failure and energy dissipation in porous rock media subjected to wave stresses

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The pore characteristics,mineral compositions,physical and mechanical properties of the subarkose sandstones were acquired by means of CT scan,X-ray diffraction and physical tests.A few physical models possessing the same pore characteristics and matrix properties but different porosities compared to the natural sandstones were developed.The 3D finite element models of the rock media with varied porosities were established based on the CT image processing of the physical models and the MIMICS software platform.The failure processes of the porous rock media loaded by the split Hopkinson pressure bar(SHPB) were simulated by satisfying the elastic wave propagation theory.The dynamic responses,stress transition,deformation and failure mechanisms of the porous rock media subjected to the wave stresses were analyzed.It is shown that an explicit and quantitative analysis of the stress,strain and deformation and failure mechanisms of porous rocks under the wave stresses can be achieved by using the developed 3D finite element models.With applied wave stresses of certain amplitude and velocity,no evident pore deformation was observed for the rock media with a porosity less than 15%.The deformation is dominantly the combination of microplasticity(shear strain),cracking(tensile strain) of matrix and coalescence of the cracked regions around pores.Shear stresses lead to microplasticity,while tensile stresses result in cracking of the matrix.Cracking and coalescence of the matrix elements in the neighborhood of pores resulted from the high transverse tensile stress or tensile strain which exceeded the threshold values.The simulation results of stress wave propagation,deformation and failure mechanisms and energy dissipation in porous rock media were in good agreement with the physical tests.The present study provides a reference for analyzing the intrinsic mechanisms of the complex dynamic response,stress transit mode,deformation and failure mechanisms and the disaster

  10. Bayesian longitudinal segmentation of hippocampal substructures in brain MRI using subject-specific atlases

    DEFF Research Database (Denmark)

    Iglesias, Juan Eugenio; Van Leemput, Koen; Augustinack, Jean

    2016-01-01

    and 23 controls), it found differences in atrophy rates between AD and controls that the cross sectional method could not detect in a number of subregions: right parasubiculum, left and right presubiculum, right subiculum, left dentate gyrus, left CA4, left HATA and right tail. In ADNI (836 subjects: 369...... not find: left presubiculum, right subiculum, left and right parasubiculum, left and right HATA. Moreover, many of the differences that the cross-sectional method already found were detected with higher significance. The presented algorithm will be made available as part of the open-source neuroimaging...... differences and significantly higher Dice overlaps than the cross-sectional approach for nearly every subregion (average across subregions: 4.5% vs. 6.5%, Dice overlap: 81.8% vs. 75.4%). The longitudinal algorithm also demonstrated increased sensitivity to group differences: in MIRIAD (69 subjects: 46 with AD...

  11. Enhanced subject-specific resting-state network detection and extraction with fast fMRI.

    Science.gov (United States)

    Akin, Burak; Lee, Hsu-Lei; Hennig, Jürgen; LeVan, Pierre

    2017-02-01

    Resting-state networks have become an important tool for the study of brain function. An ultra-fast imaging technique that allows to measure brain function, called Magnetic Resonance Encephalography (MREG), achieves an order of magnitude higher temporal resolution than standard echo-planar imaging (EPI). This new sequence helps to correct physiological artifacts and improves the sensitivity of the fMRI analysis. In this study, EPI is compared with MREG in terms of capability to extract resting-state networks. Healthy controls underwent two consecutive resting-state scans, one with EPI and the other with MREG. Subject-level independent component analyses (ICA) were performed separately for each of the two datasets. Using Stanford FIND atlas parcels as network templates, the presence of ICA maps corresponding to each network was quantified in each subject. The number of detected individual networks was significantly higher in the MREG data set than for EPI. Moreover, using short time segments of MREG data, such as 50 seconds, one can still detect and track consistent networks. Fast fMRI thus results in an increased capability to extract distinct functional regions at the individual subject level for the same scan times, and also allow the extraction of consistent networks within shorter time intervals than when using EPI, which is notably relevant for the analysis of dynamic functional connectivity fluctuations. Hum Brain Mapp 38:817-830, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  12. Signalling fiscal stress in the euro area - a country-specific early warning system

    OpenAIRE

    Hernández de Cos, Pablo; Koester, Gerrit B.; Moral-Benito, Enrique; Nickel, Christiane

    2014-01-01

    The sovereign debt crisis in the euro area has increased the interest in early warning indicators, with the aim to indicate the build?up of fiscal stress early on and to facilitate crisis prevention by a timely counteraction of fiscal and macroeconomic policies. This paper presents possible improvements to enhance existing early warning indicators for fiscal stress, especially for the euro area. We show that a country?specific approach could strongly increase the signalling power of early war...

  13. Lymphocyte subsets are influenced by positivity levels in healthy subjects before and after mild acute stress.

    Science.gov (United States)

    Caprara, Gian Vittorio; Nisini, Roberto; Castellani, Valeria; Vittorio, Pasquali; Alessandri, Guido; Vincenzo, Ziparo; Claudia, Ferlito; Valentina, Germano; Andrea, Picchianti Diamanti; Biondo, Michela Ileen; Milanetti, Francesca; Salerno, Gerardo; Vincenzo, Visco; Mario, Pietrosanti; Aniballi, Eros; Simonetta, Salemi; Angela, Santoni; D'Amelio, Raffaele

    2017-08-01

    In the current study, the possible association of positivity (POS), recently defined as general disposition to view life under positive outlook, with immune markers and post-stress modifications, was analyzed. Circulating lymphocyte subsets and serum cytokine levels were evaluated before and after a standard mild acute stress test, in 41 healthy students, previously selected by a questionnaire for their level of POS (high [POS-H] and low [POS-L]). The CD3 + and CD4 + cell frequency was higher in the POS-H students before and after acute stress. CD4 + subpopulation analysis revealed baseline higher terminally differentiated frequency in the POS-H, whereas higher effector memory frequency was present in the POS-L students. Moreover, the frequency of post-stress B cells was higher in the POS-H students. The mild-stress test was associated to an increase of the IL-10 mean values, while mean values of the other cytokines tested did not change significantly. It is tempting to speculate that IL-10 may work as biomarker of response to acute mild stress and that POS-H may be associated to a better capacity of the immune system to contrast the disturbing effects of mild acute stress. Yet further studies on lymphocyte subset absolute number and function of larger and different populations are needed to definitively prove these preliminary observations. Copyright © 2017 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

  14. Psychophysiologic responsivity in posttraumatic stress disorder: generalized hyperresponsiveness versus trauma specificity.

    Science.gov (United States)

    Casada, J H; Amdur, R; Larsen, R; Liberzon, I

    1998-11-15

    Clinically, subjects with posttraumatic stress disorder (PTSD) are viewed as hyperresponsive to a variety of stimuli. Psychophysiologic studies, however, have demonstrated hyperresponsiveness only to stimuli that are closely related to the original trauma. This set of experiments uses a variety of stimuli that vary in trauma-relatedness, arousal level, sensory modality stimulated, and degree of cognitive processing demanded to assess the extent of generalization of physiologic responses. Heart rate (HR), frontal electromyogram (EMG), and skin conductance (EDG) responses were measured during presentation of each stimulus. PTSD subjects (n = 15) had an elevated baseline EDG and increased HR and EMG responses to the trauma-related stimulus (combat sounds) compared to normal control subjects (n = 11) and combat control subjects (n = 10). No significant differences were noted between PTSD and control groups in response to non-trauma-related arousing stimuli. These results suggest that the physiologic hyperresponsivity of PTSD subjects is limited to stimuli closely associated with the inciting trauma.

  15. A Comparison of Objective and Subjective Stress in Homogeneous Male and Female Teams in a Mars Simulation

    Science.gov (United States)

    Bishop, S.; Sundaresan, A.

    Introduction The role of stress and its impact on coping performance motivation behavior cognitive functioning and psychological well-being has become a key focus for long duration missions Since all extreme environments are characterized by significant physical demands e g skiing climbing EVAs as well as inescapable environmental characteristics e g imminent danger noise isolation confinement loss of normal sensory stimuli an examination of the impact of prolong stress in analogue environments should provide insight into developing effective support and countermeasures for long duration space crews The presence of even low levels of chronic stressors if not met with functional adaptation and or countermeasures has been shown to produce subjective symptoms of stress persistent performance incompetence accelerated fatiguability altered mood states increased rate of infections and decrements in attention and cognitive Gender has been shown to cut across both individual factors and group factors including response to stress and ways of coping Generally men and women differ in many arenas such as interaction and communication styles need for affiliation responses to crowding privacy and confined spaces Men and women in homogeneous groups interact in significantly different ways than those in mixed groups Therefore differences between genders on subjective and objective responses to stress are of interest The Mars Society Utah Desert Simulation MDRS facility provides a unique opportunity to examine the interaction of

  16. Determination of stresses in gas-turbine disks subjected to plastic flow and creep

    Science.gov (United States)

    Millenson, M B; Manson, S S

    1948-01-01

    A finite-difference method previously presented for computing elastic stresses in rotating disks is extended to include the computation of the disk stresses when plastic flow and creep are considered. A finite-difference method is employed to eliminate numerical integration and to permit nontechnical personnel to make the calculations with a minimum of engineering supervision. Illustrative examples are included to facilitate explanation of the procedure by carrying out the computations on a typical gas-turbine disk through a complete running cycle. The results of the numerical examples presented indicate that plastic flow markedly alters the elastic-stress distribution.

  17. Pre- and postnatal stress and asthma in children: Temporal- and sex-specific associations

    Science.gov (United States)

    Lee, Alison; Chiu, Yueh-Hsiu Mathilda; Rosa, Maria José; Jara, Calvin; Wright, Robert O.; Coull, Brent A.; Wright, Rosalind J.

    2016-01-01

    BACKGROUND Temporal- and sex-specific effects of perinatal stress have not been examined for childhood asthma. OBJECTIVES We examined associations between pre- and/or postnatal stress and children's asthma (n=765) and effect modification by sex in a prospective cohort study. METHODS Maternal negative life events (NLEs) were ascertained prenatally and postpartum. NLEs scores were categorized as 0, 1-2, 3-4, or ≥5 to assess exposure-response relationships. We examined effects of pre- and postnatal stress on children's asthma by age 6 years modeling each as independent predictors; mutually adjusting for prenatal and postnatal stress; and finally considering interactions between pre- and postnatal stress. Effect modification by sex was examined in stratified analyses and by fitting interaction terms. RESULTS When considering stress in each period independently, among boys a dose-response relationship was evident for each level increase on the ordinal scale prenatally (OR=1.38, 95% CI 1.06, 1.79; p-for-trend=0.03) and postnatally (OR=1.53, 95% CI 1.16, 2.01; p-for-trend=0.001); among girls only the postnatal trend was significant (OR=1.60, 95% CI 1.14, 2.22; p-for-trend=0.005). Higher stress in both the pre- and postnatal periods was associated with increased odds of being diagnosed with asthma in girls [OR=1.37, 95% CI 0.98, 1.91 (pinteraction=0.07)] but not boys [OR=1.08, 95% CI 0.82, 1.42 (pinteraction=0.61)]. CONCLUSIONS While boys were more vulnerable to stress during the prenatal period, girls were more impacted by postnatal stress and cumulative stress across both periods in relation to asthma. Understanding sex and temporal differences in response to early life stress may provide unique insight into asthma etiology and natural history. PMID:26953156

  18. Resident intruder paradigm-induced aggression relieves depressive-like behaviors in male rats subjected to chronic mild stress

    Science.gov (United States)

    Wei, Sheng; Ji, Xiao-wei; Wu, Chun-ling; Li, Zi-fa; Sun, Peng; Wang, Jie-qiong; Zhao, Qi-tao; Gao, Jie; Guo, Ying-hui; Sun, Shi-guang; Qiao, Ming-qi

    2014-01-01

    Background Accumulating epidemiological evidence shows that life event stressors are major vulnerability factors for psychiatric diseases such as major depression. It is also well known that the resident intruder paradigm (RIP) results in aggressive behavior in male rats. However, it is not known how resident intruder paradigm-induced aggression affects depressive-like behavior in isolated male rats subjected to chronic mild stress (CMS), which is an animal model of depression. Material/Methods Male Wistar rats were divided into 3 groups: non-stressed controls, isolated rats subjected to the CMS protocol, and resident intruder paradigm-exposed rats subjected to the CMS protocol. Results In the sucrose intake test, ingestion of a 1% sucrose solution by rats in the CMS group was significantly lower than in control and CMS+RIP rats after 3 weeks of stress. In the open-field test, CMS rats had significantly lower open-field scores compared to control rats. Furthermore, the total scores given the CMS group were significantly lower than in the CMS+RIP rats. In the forced swimming test (FST), the immobility times of CMS rats were significantly longer than those of the control or CMS+RIP rats. However, no differences were observed between controls and CMS+RIP rats. Conclusions Our data show that aggressive behavior evoked by the resident intruder paradigm could relieve broad-spectrum depressive-like behaviors in isolated adult male rats subjected to CMS. PMID:24911067

  19. Immediate effects of chest physiotherapy on hemodynamic, metabolic, and oxidative stress parameters in subjects with septic shock.

    Science.gov (United States)

    dos Santos, Rafael S; Donadio, Márcio V F; da Silva, Gabriela V; Blattner, Clarissa N; Melo, Denizar A S; Nunes, Fernanda B; Dias, Fernando S; Squizani, Eamim D; Pedrazza, Leonardo; Gadegast, Isabella; de Oliveira, Jarbas R

    2014-09-01

    Septic shock presents as a continuum of infectious events, generating tissue hypoxia and hypovolemia, and increased oxidative stress. Chest physiotherapy helps reduce secretion, improving dynamic and static compliance, as well as improving secretion clearance and preventing pulmonary complications. The purpose of this study was to evaluate the immediate effect of chest physiotherapy on hemodynamic, metabolic, inflammatory, and oxidative stress parameters in subjects in septic shock. We conducted a quasi-experimental study in 30 subjects in septic shock, who underwent chest physiotherapy, without associated heart diseases and with vasopressors stress were evaluated before and 15 min after physiotherapy. Thirty subjects with a mean age of 61.8 ± 15.9 y and Sequential Organ Failure Assessment of 8 (range 6-10) were included. Chest physiotherapy caused a normalization of pH (P = .046) and P(aCO2) (P = .008); reduction of lactate (P = .001); and an increase in P(aO2) (P = .03), arterial oxygen saturation (P = .02), and P(aO2)/F(IO2) (P = .034), 15 min after it was applied. The results indicate that chest physiotherapy has immediate effects, improving oxygenation and reducing lactate and oxidative damage in subjects in septic shock. However, it does not cause alterations in the inflammatory and hemodynamic parameters. Copyright © 2014 by Daedalus Enterprises.

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

    Science.gov (United States)

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

    2018-01-01

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

  1. Subject-Specific Carpal Ligament Elongation in Extreme Positions, Grip, and the Dart Thrower's Motion

    Science.gov (United States)

    Rainbow, Michael J.; Kamal, Robin N.; Moore, Douglas C.; Akelman, Edward; Wolfe, Scott W.; Crisco, Joseph J.

    2015-01-01

    This study examined whether the radiocarpal and dorsal capsular ligaments limit end-range wrist motion or remain strained during midrange wrist motion. Fibers of these ligaments were modeled in the wrists of 12 subjects over multiple wrist positions that reflect high demand tasks and the dart thrower's motion. We found that many of the volar and dorsal ligaments were within 5% of their maximum length throughout the range of wrist motion. Our finding of wrist ligament recruitment during midrange and end-range wrist motion helps to explain the complex but remarkably similar intersubject patterns of carpal motion. PMID:26367853

  2. Economics of Scholarly Publishing: Exploring the Causes of Subscription Price Variations of Scholarly Journals in Business Subject-Specific Areas

    Science.gov (United States)

    Liu, Lewis G.

    2011-01-01

    This empirical research investigates subscription price variations of scholarly journals in five business subject-specific areas using the semilogarithmic regression model. It has two main purposes. The first is to address the unsettled debate over whether or not and to what extent commercial publishers reap monopoly profits by overcharging…

  3. Validating subject-specific RF and thermal simulations in the calf muscle using MR-based temperature measurements

    NARCIS (Netherlands)

    Simonis, Ffj; Raaijmakers, Aje; Lagendijk, Jjw; van den Berg, Cat

    2017-01-01

    Purpose: Ongoing discussions occur to translate the safety restrictions on MR scanners from specific absorption rate (SAR) to thermal dose. Therefore, this research focuses on the accuracy of thermal simulations in human subjects during an MR exam, which is fundamental information in that debate.

  4. Sensitivity of subject-specific models to Hill muscle-tendon model parameters in simulations of gait

    NARCIS (Netherlands)

    Carbone, V.; Krogt, M.M. van der; Koopman, H.F.J.M.; Verdonschot, N.J.

    2016-01-01

    Subject-specific musculoskeletal (MS) models of the lower extremity are essential for applications such as predicting the effects of orthopedic surgery. We performed an extensive sensitivity analysis to assess the effects of potential errors in Hill muscle-tendon (MT) model parameters for each of

  5. Sensitivity of subject-specific models to Hill muscle-tendon model parameters in simulations of gait

    NARCIS (Netherlands)

    Carbone, Vincenzo; van der Krogt, Marjolein; Koopman, Hubertus F.J.M.; Verdonschot, Nicolaas Jacobus Joseph

    2016-01-01

    Subject-specific musculoskeletal (MS) models of the lower extremity are essential for applications such as predicting the effects of orthopedic surgery. We performed an extensive sensitivity analysis to assess the effects of potential errors in Hill muscle–tendon (MT) model parameters for each of

  6. [Effect of a hypocaloric diet in the oxidative stress in obese subjects without prescription of exercise and antioxidants].

    Science.gov (United States)

    Gutiérrez, Liliana; García, José R; Rincón, María de Jesús; Ceballos, Guillermo M; Olivares, Ivonne M

    2015-07-06

    Obesity is characterized by a generalized increase of adipose tissue, high production of adipocytokines and presence of oxidative systemic stress. The objective of this study was to evaluate the changes generated in the oxidative stress and anthropometric parameters in obese subjects by the prescription of a hypocaloric diet in combination with moderate aerobic exercise and supplementation with antioxidants. Oxidative damage was determined in the plasma from 30 normal weight and 30 obese subjects. Three groups of treatment were established: Hypocaloric diet (HD), HD plus moderate aerobic exercise (HDE) and HDE plus antioxidants (DHEA). Biomarkers of oxidative stress (thiobarbituric acid reactive substances [TBARS], carbonyl groups, dityrosine) and anthropometric parameters were determined. Higher values of biomarkers of oxidative damage were observed in obese (TBARS 13.74 ± 1.2 μM; carbonyl groups 0.89 ± 0.04 nmol of osazone/mg of protein; dityrosine 478.9 ± 27.4 RFU/mg of protein) in comparison to normal weight subjects (TBARS 7.08 ± 0.8 μM; carbonyl groups 0.65 ± 0.04 nmol of osazone/mg of protein; dityrosine 126.3 ± 12.6 RFU/mg of protein), thus showing the presence of an oxidative damage. The prescription of HD decreased the oxidative damage and anthropometric parameters in the obese subjects. We did not observe additional benefit effects on these determinations with HDE or HDEA treatments. We demonstrated that an HD decreases the oxidative damage in obese subjects. Oxidative stress is an important factor in the development of comorbidity in obesity. Therefore, the prescription of a HD could be a key issue in the treatment of the disease. Copyright © 2013 Elsevier España, S.L.U. All rights reserved.

  7. The interactive association between heat shock factor 1 and heat shock proteins in primary myocardial cells subjected to heat stress.

    Science.gov (United States)

    Tang, Shu; Chen, Hongbo; Cheng, Yanfen; Nasir, Mohammad Abdel; Kemper, Nicole; Bao, Endong

    2016-01-01

    Heat shock factor 1 (HSF1) is a heat shock transcription factor that rapidly induces heat shock gene transcription following thermal stress. In this study, we subjected primary neonatal rat myocardial cells to heat stress in vitro to create a model system for investigating the trends in expression and association between various heat shock proteins (HSPs) and HSF1 under adverse environmental conditions. After the cells were subjected to heat stress at 42˚C for different periods of time, HSP and HSF1 mRNA and protein levels were detected by qPCR and western blot analysis in the heat-stressed cells. The HSF1 expression levels significantly increased in the cells following 120 min of exposure to heat stess compared to the levels observed at the beginning of heat stress exposure. HSP90 followed a similar trend in expression to HSF1, whereas HSP70 followed an opposite trend. However, no significant changes were observed in the crystallin, alpha B (CRYAB, also known as HSP beta-5) expression levels during the 480‑min period of exposure to heat stress. The interaction between the HSPs and HSF1 was analyzed by STRING 9.1, and it was found that HSF1 interacted with HSP90 and HSP70, and that it did not play a role in regulating CRYAB expression. Based on our findings, HSP70 may suppress HSF1 in rat myocardial cells under conditions of heat stress. Furthermore, our data demonstrate that HSF1 is not the key factor for all HSPs, and this was particularly the case for CRYAB.

  8. Presence of a dog reduces subjective but not physiological stress responses to an analogue trauma

    OpenAIRE

    Johanna eLass-Hennemann; Peter ePeyk; Markus eStreb; Elena eHolz; Tanja eMichael

    2014-01-01

    Dogs are known to have stress and anxiety reducing effects. Several studies have shown that dogs are able to calm people during cognitive and performance stressors. Recently, therapy dogs have been proposed as a treatment adjunct for PTSD patients. In this study we aimed to investigate, whether dogs also have anxiety- and stress reducing effect during traumatic stressors. 80 healthy female participants were randomly assigned to one of 4 conditions. They were exposed to a traumatic film clip (...

  9. Study of a new alternative antioxidant in soybean plants subjected to abiotic stress

    International Nuclear Information System (INIS)

    Zilli, C.; Santa Cruz, D.; Caggiano, E.; Romanello, M.; Tomaro, M.; Balestrasse, K.

    2010-01-01

    We have recently, demonstrated that the induction of heme oxygenase-1 (HO-1) plays a protective role for soybean plants against oxidative stress produced by cadmium and UV-B radiation. At this moment we propose to investigate if the enzyme has the same capacity against another type of abiotic stress, such as drought, for to demonstrate that heme oxygenase acts as an enzyme of plant antioxidant defense system under several different stress situations, as occur in mammalian tissues. To carry out this objective we propose to study, in leaf, root and nodule of soybean plants, the oxidative stress generation; the behavior of classical antioxidant system; the behavior of HO-1 activity and protein and gene expression; the effect of its reaction products and inhibitors on the oxidative stress parameters; the signaling mechanism that produce HO-1 induction and the immunohistochemistry localization of the enzyme in the different plant tissues. The results obtained let us undoubtedly demonstrate the involvement of HO-1 in the antioxidant defense system in plants. This finding will allow the increase in the knowledge of the defense mechanisms in interesting economic plants for our country, such as soybean, and against drought, an abiotic stress considered one of the most important factors limiting plant performance and yield worldwide. (authors)

  10. Investigations on GSK-3β/NF-kB signaling in stress and stress adaptive behavior in electric foot shock subjected mice.

    Science.gov (United States)

    Bali, Anjana; Jaggi, Amteshwar Singh

    2016-04-01

    The present study was designed to explore the role of GSK-3β and NF-kB signaling in electric foot shock-induced stress and stress adaptation. Mice were subjected to foot shocks of 0.5mA intensity and 1s duration of 1h to produce acute stress. Animals were exposed to the same stressor for 5 days to induce stress adaptation. The behavioral alterations were assessed using the actophotometer, hole board, open field and social interaction tests. The serum corticosterone levels were assessed as a marker of the HPA axis. The levels of total GSK-3β, p-GSK-3β-S9 and p-NF-kB were determined in the hippocampus, frontal cortex and amygdala. Acute electric foot shock stress produced behavioral and biochemical changes; decreased the levels of p-GSK-3β-S9, produced no change in total GSK-3β levels and increased p-NF-kB levels in the brain. However, repeated exposure of foot shock stress restored the behavioral and biochemical changes along with normalization of p-GSK-3β-S9 and p-NF-kB levels. Administration of AR-A01, a selective GSK-3β inhibitor, or diethyldithiocarbamic acid (DDTC), a selective NF-kB inhibitor, diminished acute stress-induced behavioral and biochemical changes. Furthermore, AR-A014418 normalized acute stress-induced alterations in p-GSK-3β-S9 and p-NF-kB levels, however, DDTC selectively restored NF-kB levels without any change in p-GSK-3β-S9 levels. It probably suggests that NF-kB is a downstream mediator of the GSK-3 signaling cascade. It may conclude that acute stress associated decrease in p-GSK-3β-S9 and increase in p-NF-kB levels in the brain contribute in the development of behavioral and biochemical alterations and normalization of GSK-3β/NF-kB signaling may contribute in stress adaptive behavior in response to repeated electric foot shock-subjected mice. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Activation of prefrontal cortex and anterior thalamus in alcoholic subjects on exposure to alcohol-specific cues.

    Science.gov (United States)

    George, M S; Anton, R F; Bloomer, C; Teneback, C; Drobes, D J; Lorberbaum, J P; Nahas, Z; Vincent, D J

    2001-04-01

    Functional imaging studies have recently demonstrated that specific brain regions become active in cocaine addicts when they are exposed to cocaine stimuli. To test whether there are regional brain activity differences during alcohol cue exposure between alcoholic subjects and social drinkers, we designed a functional magnetic resonance imaging (fMRI) protocol involving alcohol-specific cues. Ten non-treatment-seeking adult alcoholic subjects (2 women) (mean [SD] age, 29.9 [9.9] years) as well as 10 healthy social drinking controls of similar age (2 women) (mean [SD] age, 29.4 [8.9] years) were recruited, screened, and scanned. In the 1.5-T magnetic resonance imaging scanner, subjects were serially rated for alcohol craving before and after a sip of alcohol, and after a 9-minute randomized presentation of pictures of alcoholic beverages, control nonalcoholic beverages, and 2 different visual control tasks. During picture presentation, changes in regional brain activity were measured with the blood oxygen level-dependent technique. Alcoholic subjects, compared with the social drinking subjects, reported higher overall craving ratings for alcohol. After a sip of alcohol, while viewing alcohol cues compared with viewing other beverage cues, only the alcoholic subjects had increased activity in the left dorsolateral prefrontal cortex and the anterior thalamus. The social drinkers exhibited specific activation only while viewing the control beverage pictures. When exposed to alcohol cues, alcoholic subjects have increased brain activity in the prefrontal cortex and anterior thalamus-brain regions associated with emotion regulation, attention, and appetitive behavior.

  12. AC loss characteristics of Bi2223/Ag sheathed tape wires subjected to mechanical strains and stresses

    International Nuclear Information System (INIS)

    Tsukamoto, Osami; Li, Z

    2007-01-01

    The influence of uniaxial tensile stress-strain on the AC loss characteristics of multifilamentary Bi2223/Ag sheathed tape wires was investigated. The uniaxial tensile stress-strain was applied to the sample wire in liquid nitrogen at atmospheric pressure, and the AC losses (transport, magnetization and total losses) were measured by an electric method. Two kinds of wire, oxide-dispersion strengthened Ag-alloy sheathed and Ag-alloy sheathed wires, were tested. The stress-strain curves of the tested wires were divided in three regions, i.e. elastic deformation, continuous plastic deformation and serrated-like plastic deformation regions, though the ranges of those regions were different for different kinds of wire. In the elastic and continuous plastic regions, the stress-strain curve was smooth and continuous, and in the serrated-like plastic region, the curve was rough. In the serrated-like plastic region, the wires kept elongating, while increase of the tensile stress was suspended. Dependences of the critical currents on the stress-strain were generally as follows. While decreases of the wire critical currents were in the range of less than 4% of the original values of the no-stress condition, the critical currents of the wires were reversible, that is, the critical currents recovered the original values at zero stress when the stress were released, regardless of whether the wires were in the elastic or continuous plastic region. In the continuous plastic region, the critical currents decreased up to 10%-15% of the original values and the critical currents were irreversible when the degradations of the critical currents exceeded about 4%. In the serrated-like plastic regions, the critical currents were more severely degraded. The AC loss characteristics of the wires are different in those regions. In the elastic and continuous plastic regions, the absolute values of AC losses were dependent on the stress-strain. However, the dependences of those normalized

  13. Disease specific stress of tumor patients at the beginning of radiotherapy. Effect on psychosocial support requirement

    International Nuclear Information System (INIS)

    Sehlen, S.; Hollenhorst, H.; Schymura, B.; Firsching, M.; Duehmke, E.; Herschbach, P.

    2001-01-01

    Purpose: Radiotherapy brings a tumor patient into a special life situation in which different variables play a role of often unknown importance. The goal of this study was to investigate disease specific stress of tumor patients at the beginning of radiotherapy with established psychodiagnostic questionnaires and to evaluate the effect on psychosocial support requirement in order to reduce stress and to improve quality of life and compliance during radiotherapeutical treatment. Patients and Methods: 732 patients were screened, of whom 446 (60.9%) fulfilled the criteria for inclusion (refusals 21.0%, low Karnofsky performance status 6.6%, management problems 3.4%, language barriers 3.0%, cognitive restrictions 2.6%, death 2.5%). Disease specific aspects of stress in the questionnaire (Fragebogen zur Belastung von Krebspatienten, FBK), life situation (LS) and self-defined care requirements (BB) were self-rated by patients with different tumor types before radiotherapy. Medical and sociodemographic data were also documented. We investigated 446 patients (262 male, 184 female; median age 60.0 years) with different diagnoses. Results: Stress was observed mainly due to reduction of efficiency, anxiety and pain on the subscales. Women had a significant higher stress on subscales of pain (p=0.016) and anxiety (p=0.009), patients younger than 45 years in the subscale information (p=0.002) and patients older than 45 and younger than 60 years in the subscale anxiety (p=0.002) and the total score (p=0.003). Patients with mamma carcinoma had the highest stress. The maximum percentages of patients under high stress were found for the subscales of efficiency (43%) and anxiety (40%). The support requirement was characterized by the need of more medical information and dialogue with the doctor. We saw a significant correlation of high stress and high care requirement. Conclusions: Psychosocial support should be founded on psychosocial stress diagnostic and self-defined care

  14. Indirect detection of an epitope-specific response to HIV-1 gp120 immunization in human subjects.

    Directory of Open Access Journals (Sweden)

    Evgeny Shmelkov

    Full Text Available A specific response of human serum neutralizing antibodies (nAb to a conformational epitope as a result of vaccination of human subjects with the surface envelope glycoprotein (gp120 of HIV-1 has not previously been documented. Here, we used computational analysis to assess the epitope-specific responses of human subjects, which were immunized with recombinant gp120 immunogens in the VAX003 and VAX004 clinical trials. Our computational methodology--a variation of sieve analysis--compares the occurrence of specific nAb targeted conformational 3D epitopes on viruses from infected individuals who received vaccination to the occurrence of matched epitopes in the viruses infecting placebo subjects. We specifically studied seven crystallographically defined nAb targeted conformational epitopes in the V3 loop, an immunogenic region of gp120. Of the six epitopes present in the immunogens and targeted by known monoclonal neutralizing antibodies, only the one targeted by the anti-V3 nAb 2219 exhibited a significant reduction in occurrence in vaccinated subjects compared to the placebo group. This difference occurred only in the VAX003 Thailand cohort. No difference was seen between vaccinated and placebo groups for the occurrence of an epitope that was not present in the immunogen. Thus, it can be theorized that a specific 2219-like human neutralizing antibody immune response to AIDSVAX immunization occurred in the VAX003 cohort, and that this response protected subjects from a narrow subset of HIV-1 viruses circulating in Thailand in the 1990s and bearing the conformational epitope targeted by the neutralizing antibody 2219.

  15. Subject-specific computer simulation model for determining elbow loading in one-handed tennis backhand groundstrokes.

    Science.gov (United States)

    King, Mark A; Glynn, Jonathan A; Mitchell, Sean R

    2011-11-01

    A subject-specific angle-driven computer model of a tennis player, combined with a forward dynamics, equipment-specific computer model of tennis ball-racket impacts, was developed to determine the effect of ball-racket impacts on loading at the elbow for one-handed backhand groundstrokes. Matching subject-specific computer simulations of a typical topspin/slice one-handed backhand groundstroke performed by an elite tennis player were done with root mean square differences between performance and matching simulations of elbow loading for a topspin and slice one-handed backhand groundstroke is relatively small. In this study, the relatively small differences in elbow loading may be due to comparable angle-time histories at the wrist and elbow joints with the major kinematic differences occurring at the shoulder. Using a subject-specific angle-driven computer model combined with a forward dynamics, equipment-specific computer model of tennis ball-racket impacts allows peak internal loading, net impulse, and shock due to ball-racket impact to be calculated which would not otherwise be possible without impractical invasive techniques. This study provides a basis for further investigation of the factors that may increase elbow loading during tennis strokes.

  16. Subject-specific optimization of channel currents for multichannel transcranial magnetic stimulation.

    Science.gov (United States)

    Cline, Christopher C; Johnson, Nessa N; He, Bin

    2015-01-01

    The goal of this work is to develop a focal transcranial magnetic stimulation (TMS) system using a multichannel coil array for high-resolution neuromodulation. We proposed a novel spatially-distributed stimulation strategy to significantly improve the focality of TMS. Computer simulations were conducted to evaluate the proposed approach and test the merits of multichannel TMS. Three different multichannel coil arrays were modeled in addition to a conventional figure-8 coil for comparison. Simulations were performed on finite element head models of six subjects constructed from anatomical MR images via an automated pipeline. Multichannel TMS arrays exhibited significantly more focal induced electric field magnitudes compared to the figure-8 coil. Additionally, electrical steering of stimulation sites without physical movement of the coil array was demonstrated.

  17. Cultural Specific Effects on the Recognition of Basic Emotions: A Study on Italian Subjects

    Science.gov (United States)

    Esposito, Anna; Riviello, Maria Teresa; Bourbakis, Nikolaos

    The present work reports the results of perceptual experiments aimed to investigate if some of the basic emotions are perceptually privileged and if the cultural environment and the perceptual mode play a role in this preference. To this aim, Italian subjects were requested to assess emotional stimuli extracted from Italian and American English movies in the single (either video or audio alone) and the combined audio/video mode. Results showed that anger, fear, and sadness are better perceived than surprise, happiness in both the cultural environments (irony instead strongly depend on the language), that emotional information is affected by the communication mode and that language plays a role in assessing emotional information. Implications for the implementation of emotionally colored interactive systems are discussed.

  18. The estimation of branching curves in the presence of subject-specific random effects.

    Science.gov (United States)

    Elmi, Angelo; Ratcliffe, Sarah J; Guo, Wensheng

    2014-12-20

    Branching curves are a technique for modeling curves that change trajectory at a change (branching) point. Currently, the estimation framework is limited to independent data, and smoothing splines are used for estimation. This article aims to extend the branching curve framework to the longitudinal data setting where the branching point varies by subject. If the branching point is modeled as a random effect, then the longitudinal branching curve framework is a semiparametric nonlinear mixed effects model. Given existing issues with using random effects within a smoothing spline, we express the model as a B-spline based semiparametric nonlinear mixed effects model. Simple, clever smoothness constraints are enforced on the B-splines at the change point. The method is applied to Women's Health data where we model the shape of the labor curve (cervical dilation measured longitudinally) before and after treatment with oxytocin (a labor stimulant). Copyright © 2014 John Wiley & Sons, Ltd.

  19. Towards Subject-Specific Strength Training Design through Predictive Use of Musculoskeletal Models

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    Michael Plüss

    2018-01-01

    Full Text Available Lower extremity dysfunction is often associated with hip muscle strength deficiencies. Detailed knowledge of the muscle forces generated in the hip under specific external loading conditions enables specific structures to be trained. The aim of this study was to find the most effective movement type and loading direction to enable the training of specific parts of the hip muscles using a standing posture and a pulley system. In a novel approach to release the predictive power of musculoskeletal modelling techniques based on inverse dynamics, flexion/extension and ab-/adduction movements were virtually created. To demonstrate the effectiveness of this approach, three hip orientations and an external loading force that was systematically rotated around the body were simulated using a state-of-the art OpenSim model in order to establish ideal designs for training of the anterior and posterior parts of the M. gluteus medius (GM. The external force direction as well as the hip orientation greatly influenced the muscle forces in the different parts of the GM. No setting was found for simultaneous training of the anterior and posterior parts with a muscle force higher than 50% of the maximum. Importantly, this study has demonstrated the use of musculoskeletal models as an approach to predict muscle force variations for different strength and rehabilitation exercise variations.

  20. EFFICACY OF POST ISOMETRIC RELAXATION VERSUS STATIC STRECHING IN SUBJECTS WITH CHRONIC NON SPECIFIC NECK PAIN

    Directory of Open Access Journals (Sweden)

    P.Haritha

    2015-12-01

    Full Text Available Background: Neck pain is a common problem within our society. Upper trapezius sternocleidomastoid and the levator scapulae are the most common postural muscles that tends to get shorten leading to restricted neck mobility. There is lack of evidence to allow conclusions to be drawn about the effectiveness of post isometric relaxation when compared with static stretching exercises. The aim is to find out the effectiveness of Post isometric relaxation Versus Static stretching in the subjects with chronic nonspecific neck pain. To evaluate the effectiveness of post isometric relaxation technique on pain by using Visual analoge scale, range of motion by using Universal Goniometry, and functional disability by using Neck Disability Index in chronic nonspecific neck pain. Methods: A convenient sample of thirty seven subjects was diagnosed with nonspecific neck pain was randomly allocated to one of the two treatment groups on the basis of the inclusion criteria. The experimental group (n=15 received three sessions of post isometric relaxation technique for trapezius, sternocleidomastoid and the levator scapulae and control group (n=15 received the three sessions of static stretching for trapezius, sternocliedomastiod and levator scapulae for four weeks. Results: Non parametric tests demonstrated a statistically significant difference with experimental group showing greater improvement in ROM, VAS, and NDI than the control group and significant difference within the group also. Conclusion: This study concluded and the results reflected that post isometric relaxation technique group had better improvement in reduction of pain, improvement in the range of motion, and increased neck functional activities than the static stretching group.

  1. Identification of imprinted genes subject to parent-of-origin specific expression in Arabidopsis thaliana seeds

    LENUS (Irish Health Repository)

    McKeown, Peter C

    2011-08-12

    Abstract Background Epigenetic regulation of gene dosage by genomic imprinting of some autosomal genes facilitates normal reproductive development in both mammals and flowering plants. While many imprinted genes have been identified and intensively studied in mammals, smaller numbers have been characterized in flowering plants, mostly in Arabidopsis thaliana. Identification of additional imprinted loci in flowering plants by genome-wide screening for parent-of-origin specific uniparental expression in seed tissues will facilitate our understanding of the origins and functions of imprinted genes in flowering plants. Results cDNA-AFLP can detect allele-specific expression that is parent-of-origin dependent for expressed genes in which restriction site polymorphisms exist in the transcripts derived from each allele. Using a genome-wide cDNA-AFLP screen surveying allele-specific expression of 4500 transcript-derived fragments, we report the identification of 52 maternally expressed genes (MEGs) displaying parent-of-origin dependent expression patterns in Arabidopsis siliques containing F1 hybrid seeds (3, 4 and 5 days after pollination). We identified these MEGs by developing a bioinformatics tool (GenFrag) which can directly determine the identities of transcript-derived fragments from (i) their size and (ii) which selective nucleotides were added to the primers used to generate them. Hence, GenFrag facilitates increased throughput for genome-wide cDNA-AFLP fragment analyses. The 52 MEGs we identified were further filtered for high expression levels in the endosperm relative to the seed coat to identify the candidate genes most likely representing novel imprinted genes expressed in the endosperm of Arabidopsis thaliana. Expression in seed tissues of the three top-ranked candidate genes, ATCDC48, PDE120 and MS5-like, was confirmed by Laser-Capture Microdissection and qRT-PCR analysis. Maternal-specific expression of these genes in Arabidopsis thaliana F1 seeds was

  2. Identification of imprinted genes subject to parent-of-origin specific expression in Arabidopsis thaliana seeds

    Directory of Open Access Journals (Sweden)

    Wennblom Trevor J

    2011-08-01

    Full Text Available Abstract Background Epigenetic regulation of gene dosage by genomic imprinting of some autosomal genes facilitates normal reproductive development in both mammals and flowering plants. While many imprinted genes have been identified and intensively studied in mammals, smaller numbers have been characterized in flowering plants, mostly in Arabidopsis thaliana. Identification of additional imprinted loci in flowering plants by genome-wide screening for parent-of-origin specific uniparental expression in seed tissues will facilitate our understanding of the origins and functions of imprinted genes in flowering plants. Results cDNA-AFLP can detect allele-specific expression that is parent-of-origin dependent for expressed genes in which restriction site polymorphisms exist in the transcripts derived from each allele. Using a genome-wide cDNA-AFLP screen surveying allele-specific expression of 4500 transcript-derived fragments, we report the identification of 52 maternally expressed genes (MEGs displaying parent-of-origin dependent expression patterns in Arabidopsis siliques containing F1 hybrid seeds (3, 4 and 5 days after pollination. We identified these MEGs by developing a bioinformatics tool (GenFrag which can directly determine the identities of transcript-derived fragments from (i their size and (ii which selective nucleotides were added to the primers used to generate them. Hence, GenFrag facilitates increased throughput for genome-wide cDNA-AFLP fragment analyses. The 52 MEGs we identified were further filtered for high expression levels in the endosperm relative to the seed coat to identify the candidate genes most likely representing novel imprinted genes expressed in the endosperm of Arabidopsis thaliana. Expression in seed tissues of the three top-ranked candidate genes, ATCDC48, PDE120 and MS5-like, was confirmed by Laser-Capture Microdissection and qRT-PCR analysis. Maternal-specific expression of these genes in Arabidopsis thaliana F1

  3. Subjective stress, role perceptions and coping strategies among mental health nurses

    Directory of Open Access Journals (Sweden)

    Spyridoula Doupi

    2015-09-01

    Full Text Available Introduction: Lack of nursing personnel, the consequent nurses’ work pressure within health care units and the particularities of nursing services provision in mental health institutions, render the examination of stress at work a necessity. Aim: The current study aims in presenting the stress levels among nurses in mental health institutions, their perceptions of the nursing role and the coping strategies they use. Methodology: This cross-sectional descriptive study was conducted in the population of 85 nurses in mental health open and closed units of two public hospitals of Attica, one psychiatric and one general. Participants filled in questionnaires on demographic characteristics, perceived stress, role conflict and ambiguity and ways of coping with stressful situations. Results: 57 women (67,1% and 28 men (32,9%, aged (mean 41,08 years, mostly married (74,1% and graduates of Technological institutions (29,4% participated in the study. Most were working 16-20 years (32,9%, were nurses (71,8% and were being occupied in a psychiatric structure for more than 21 years (27,1%. Female nurses had a greater amount of role ambiguity (p=0.048 and higher levels of stress (p=0.007. The same pattern was observed to those who worked for more years (p=0.038. Those who were not satisfied with their job suffered from greater role ambiguity (p<0.001 and conflict (p<0.001, while the graduates of secondary education and specialised nurses had higher levels of stress (p=0.004. Nurses with most working years in a psychiatric facility, experienced greater role conflict (p=0.034. Role ambiguity was positively associated with role conflict (p<0.001, perceived stress (p=0.006, positive approach strategy (negatively; p=0.003, self-rated health (negatively; p=0.003 and age (negatively; p=0.006. Perceived stress was negatively associated with positive approach (p=0.019 and self-rated health (p<0.001. Finally, positive approach was positively associated with social

  4. Cell-type-specific role for nucleus accumbens neuroligin-2 in depression and stress susceptibility.

    Science.gov (United States)

    Heshmati, Mitra; Aleyasin, Hossein; Menard, Caroline; Christoffel, Daniel J; Flanigan, Meghan E; Pfau, Madeline L; Hodes, Georgia E; Lepack, Ashley E; Bicks, Lucy K; Takahashi, Aki; Chandra, Ramesh; Turecki, Gustavo; Lobo, Mary Kay; Maze, Ian; Golden, Sam A; Russo, Scott J

    2018-01-30

    Behavioral coping strategies are critical for active resilience to stress and depression; here we describe a role for neuroligin-2 (NLGN-2) in the nucleus accumbens (NAc). Neuroligins (NLGN) are a family of neuronal postsynaptic cell adhesion proteins that are constituents of the excitatory and inhibitory synapse. Importantly, NLGN-3 and NLGN-4 mutations are strongly implicated as candidates underlying the development of neuropsychiatric disorders with social disturbances such as autism, but the role of NLGN-2 in neuropsychiatric disease states is unclear. Here we show a reduction in NLGN-2 gene expression in the NAc of patients with major depressive disorder. Chronic social defeat stress in mice also decreases NLGN-2 selectively in dopamine D1-positive cells, but not dopamine D2-positive cells, within the NAc of stress-susceptible mice. Functional NLGN-2 knockdown produces bidirectional, cell-type-specific effects: knockdown in dopamine D1-positive cells promotes subordination and stress susceptibility, whereas knockdown in dopamine D2-positive cells mediates active defensive behavior. These findings establish a behavioral role for NAc NLGN-2 in stress and depression; provide a basis for targeted, cell-type specific therapy; and highlight the role of active behavioral coping mechanisms in stress susceptibility.

  5. Age-Specific Determinants of Pulse Wave Velocity among Metabolic Syndrome Components, Inflammatory Markers, and Oxidative Stress.

    Science.gov (United States)

    Kim, Minkyung; Kim, Minjoo; Yoo, Hye Jin; Lee, Seung Yeon; Lee, Sang-Hyun; Lee, Jong Ho

    2018-02-01

    Pulse wave velocity (PWV) is thought to have different relationships with metabolic syndrome (MS) components, inflammatory markers, and oxidative stress, according to age. However, age-specific determinants of PWV have not yet been studied. We investigated age-dependent relationships among PWV and MS components, inflammatory markers, and oxidative stress. A total of 4,318 subjects were divided into 4 groups: 19-34 y (n=687), 35-44 y (n=1,413), 45-54 y (n=1,384), and 55-79 y (n=834). MS components, brachial-ankle PWV (baPWV), high-sensitivity C-reactive protein (hs-CRP), and oxidative stress markers were measured. There were age-related increases in MS, body mass index (BMI), waist circumference, systolic blood pressure (SBP), diastolic BP (DBP), triglycerides, glucose, hs-CRP, oxidized low-density lipoprotein (LDL), 8-epi-prostaglandin F 2α (8-epi-PGF 2α ), and baPWV. BaPWV was significantly associated with sex and elevated BP in the 19-34 y group; with age, sex, BMI, elevated BP and triglycerides in the 35-44 y group; with age, sex, elevated BP, fasting glucose, hs-CRP and oxidized LDL in the 45-54 y group; and with age, BMI, elevated BP, fasting glucose and oxidized LDL in the 55-79 y group. Our results show that age-related increases in baPWV are associated with age-related changes in MS components, inflammatory markers, and oxidative stress. However, each of these factors has an age-specific, different impact on arterial stiffness. In particular, oxidative stress may be independently associated with arterial stiffness in individuals older than 45 y.

  6. The effect of Kinesio Taping on postural control in subjects with non-specific chronic low back pain.

    Science.gov (United States)

    Abbasi, Soheila; Rojhani-Shirazi, Zahra; Shokri, Esmaeil; García-Muro San José, Francisco

    2018-04-01

    The aim of this study was to investigate the possible alterations in postural control during upright standing in subjects with non-specific chronic low back pain and the effect of Kinesio taping on the postural control. Twenty subjects with non-specific chronic low back pain and twenty healthy subjects participated in this study. The center of pressure excursion was evaluated before the intervention for both groups, and immediately after intervention for the low back pain group. Independent sample t-test, Mann-Whitney test and repeated measure ANOVA were used for the statistical analysis of the data. There were significant differences in the center of pressure excursion between the low back pain group versus the healthy group. The results of the ANOVA demonstrated a statistically significant difference in the mean COP displacement and velocity before Kinesio Taping, immediately after, and 24 h after in the low back pain group. There are poor postural control mechanisms in subjects with non-specific chronic low back pain. Kinesio taping seems to change postural control immediately and have lasting effects until the day after. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Altered immunological response in mice subjected to stress and exposed to fungal spores

    Science.gov (United States)

    Kurup, Viswanath P.; Choi, Hongyung; Kumar, Anoopa; Murali, Pazhayannur S.; Mishra, S. K.; Pierson, Duane L.

    1992-01-01

    Space flight and related factors such as stress appear to have an adverse effect on astronauts' immune systems. The presence of potentially pathogenic microbes including several genera of fungi reported from spacecraft environment may be a cause of concern in such situations. In order to study the role of such organisms in causing opportunistic or allergic diseases in crewmembers, we have tried to develop an animal model. BALB/c mice were suspended upside down for varying periods of time to induce stress, and their lymphocyte functions were evaluated. These studies indicate that the stress resulted in lowered mitogen induced lymphocyte stimulation as represented by 3H-thymidine uptake. We have also studied the ability of these animals to respond to Aspergillus fumigatus spores. The results of the study clearly demonstrate a definite down-regulation in T-cell proliferation and a higher incidence of infection with A. fumigatus.

  8. Protective Effect of Theaflavin on Erythrocytes Subjected to In Vitro Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Mahejabeen Fatima

    2013-01-01

    Full Text Available Antioxidant and free radical scavenging effect of black tea theaflavins has been shown in many epidemiological studies. In the present work we report the protective mechanism of tea theaflavins on biomarkers of oxidative stress, which are elevated during stress conditions. We hereby report the in vitro effect of theaflavins on erythrocyte malondialdehyde (MDA, intracellular reduced glutathione (GSH, and plasma membrane redox system (PMRS of rats. The effect of theaflavin on PMRS has also been validated through an in silico docking simulation study using Molegro Virtual Docker (MVD. We report that theaflavins show significant protection to erythrocyte against oxidative stress induced by tert-butyl hydroperoxide (t-BHP. The findings suggest a possible protective role of theaflavins as antioxidant.

  9. Stress-sensitive tissue regeneration in viscoelastic biomaterials subjected to modulated tensile strain.

    Science.gov (United States)

    Belfiore, Laurence A; Floren, Michael L; Paulino, Alexandre T; Belfiore, Carol J

    2011-09-01

    This research contribution addresses the mechanochemistry of intra-tissue mass transfer for nutrients, oxygen, growth factors, and other essential ingredients that anchorage-dependent cells require for successful proliferation on biocompatible surfaces. The unsteady state reaction-diffusion equation (i.e., modified diffusion equation) is solved according to the von Kármán-Pohlhausen integral method of boundary layer analysis when nutrient consumption and tissue regeneration are stimulated by harmonically imposed stress. The mass balance with diffusion and stress-sensitive kinetics represents a rare example where the Damköhler and Deborah numbers appear together in an effort to simulate the development of mass transfer boundary layers in porous viscoelastic biomaterials. The Boltzmann superposition integral is employed to calculate time-dependent strain in terms of the real and imaginary components of dynamic compliance for viscoelastic solids that transmit harmonic excitation to anchorage-dependent cells. Rates of nutrient consumption under stress-free conditions are described by third-order kinetics which include local mass densities of nutrients, oxygen, and attached cells that maintain dynamic equilibrium with active protein sites in the porous matrix. Thinner nutrient mass transfer boundary layers are stabilized at shorter dimensionless diffusion times when the stress-free intra-tissue Damköhler number increases above its initial-condition-sensitive critical value. The critical stress-sensitive intra-tissue Damköhler number, above which it is necessary to consider the effect of harmonic strain on nutrient consumption and tissue regeneration, is proportional to the Deborah number and corresponds to a larger fraction of the stress-free intra-tissue Damköhler number in rigid biomaterials. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Changes in salivary microbiota increase volatile sulfur compounds production in healthy male subjects with academic-related chronic stress.

    Directory of Open Access Journals (Sweden)

    Bruno Dias Nani

    Full Text Available To investigate the associations among salivary bacteria, oral emanations of volatile sulfur compounds, and academic-related chronic stress in healthy male subjects.Seventy-eight healthy male undergraduate dental students were classified as stressed or not by evaluation of burnout, a syndrome attributed to academic-related chronic stress. This evaluation was carried out using the Maslach Burnout Inventory-Student Survey questionnaire. Oral emanations of hydrogen sulfide, methyl mercaptan, and dimethyl sulfide were measured using an Oral Chroma™ portable gas chromatograph. The amounts in saliva of total bacteria and seven bacteria associated with halitosis were quantified by qPCR. The in vitro production of H2S by S. moorei and/or F. nucleatum was also measured with the Oral Chroma™ instrument.The stressed students group showed increased oral emanations of hydrogen sulfide and dimethyl sulfide, together with higher salivary Solobacterium moorei levels (p < 0.05, Mann Whitney test. There were moderate positive correlations between the following pairs of variables: Fusobacterium nucleatum and S. moorei; F. nucleatum and hydrogen sulfide; Tannerella forsythia and F. nucleatum; T. forsythia and S. moorei. These correlations only occurred for the stressed group (p < 0.05, Spearman correlation. The in vitro experiment demonstrated that S. moorei increased H2S production by F. nucleatum (p < 0.05, ANOVA and Tukey's test.The increased amount of S. moorei in saliva, and its coexistence with F. nucleatum and T. forsythia, seemed to be responsible for increased oral hydrogen sulfide in the healthy male stressed subjects.

  11. Other subjects, other school? Strategies and practices in the context of specific schools for the deaf

    Directory of Open Access Journals (Sweden)

    Liane Camatti

    2011-10-01

    Full Text Available The deaf community has recursively searched for specific schools for the deaf because it is a space where you could find safety and resistance conditions. Through this article, it seeks to understand how the assumptions that support the school institution are directed, given the nearness with the movements for the deaf. To accomplish this approach, we used excerpts from interviews with deaf, teachers and students from different specifically schools for the deaf of the State of Rio Grande do Sul. The studies of the post-structuralist concern provided the theoretical tools that enabled the analysis. Through this research, it became clear how the deaf community falls within the school, making the assumptions of cultural capital legitimized in the school for the deaf. Nevertheless, it was possible to look at how the processes of discipline inherent in the educational institution happen the same way in the school for the deaf, even though it was taken by the deaf as the site of redemption and as its largest trench.

  12. Contact stresses by rounded punch subject to axial and transverse shear

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyung Kyu [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1999-05-01

    Contact shear stresses by rounded punch were evaluated numerically. Numerical program was successfully implemented by using an influence function method. To simulate the physical fretting problem, a closed load path of shear was considered. The influence functions on surface displacements fo both axial and transverse direction were calculated using a triangular shear traction element. Behaviour of the contact surface, such as stick and slip region during the load path was investigated together with compliance change. Irreversibility of the shear stress was shown. The importance and the utilization of the present research were discussed for analyzing the material failure induced by contact such as fretting wear and fatigue.

  13. Contact stresses by rounded punch subject to axial and transverse shear

    International Nuclear Information System (INIS)

    Kim, Hyung Kyu

    1999-01-01

    Contact shear stresses by rounded punch were evaluated numerically. Numerical program was successfully implemented by using an influence function method. To simulate the physical fretting problem, a closed load path of shear was considered. The influence functions on surface displacements fo both axial and transverse direction were calculated using a triangular shear traction element. Behaviour of the contact surface, such as stick and slip region during the load path was investigated together with compliance change. Irreversibility of the shear stress was shown. The importance and the utilization of the present research were discussed for analyzing the material failure induced by contact such as fretting wear and fatigue

  14. Cardio-respiratory response of young adult Indian male subjects to stress: Effects of progressive muscle relaxation

    Directory of Open Access Journals (Sweden)

    Arunima Chaudhuri

    2014-01-01

    Full Text Available Background: Stress and anxiety have become an integral part of our lives. Of late, this has resulted in the increase in incidence of hypertension and coronary heart disease. Objectives: To assess the effect of progressive muscle relaxation (PMR on young adult males and its role in the modulation of cardio-respiratory response on exposure to stress. Materials and Methods: This prospective cross-sectional study was conducted in a tertiary care referral hospital. Undergraduate male students under stress were chosen for the study. Fasting blood samples were drawn to analyze sugar and lipid profile, followed by anthropometric measurements and ECG. In the resting condition, blood pressure, pulse rate, and spirometric parameters; forced vital capacities (FVC, and forced expiratory volume in 1 sec (FEV 1 % were measured. Then, they were made to exercise with bicycle ergometer and post exercise, the vital parameters were recorded. All subjects were given a training of Jacobson′s Progressive Muscular Relaxation and asked to practice this technique for 3 months. All parameters were re-evaluated. Results: Significant decreases in resting heart rate, systolic blood pressure and diastolic blood pressure, total cholesterol, triglyceride, and low density lipoprotein (LDL cholesterol levels of subjects were seen after PMR training. Exercise-induced rise in heart rate and blood pressure were also significantly less in subjects following PMR training. Conclusion: Progressive muscle relaxation helps in modulation of heart rate, blood pressure, and lipid profile in healthy normal adult male individuals.

  15. Protein carbonyl: An oxidative stress marker in gingival crevicular fluid in healthy, gingivitis, and chronic periodontitis subjects

    Directory of Open Access Journals (Sweden)

    Avani R Pradeep

    2013-01-01

    Full Text Available Background: A defined role for reactive oxygen species (ROS in the tissue destruction that characterizes periodontitis has been described. Protein carbonyl (PC is the most widely used biomarker for oxidative damage to proteins, and reflects cellular damage induced by multiple forms of ROS. The purpose of this study is to determine the presence of PC in gingival crevicular fluid (GCF in healthy, gingivitis, and chronic periodontitis (CP subjects and to find an association, if any. Materials and Methods: A total number of 75 subjects (38 males and 37 females were selected based on their clinical parameters into three groups: Group 1 (25 healthy subjects, Group 2 (25 gingivitis subjects, and Group 3 (25 CP subjects. GCF samples were collected to estimate the levels of PC. Results: The PC concentration in GCF was highest in subjects with CP as compared to gingivitis and healthy subjects and a significant association was observed between GCF PC levels and all periodontal parameters. Conclusion: There was an increase in PC levels in GCF as the disease process progressed from healthy to gingivitis and CP, suggesting a role for increased oxidative stress in CP.

  16. Refining the multisystem view of the stress response: coordination among cortisol, alpha-amylase, and subjective stress in response to relationship conflict.

    Science.gov (United States)

    Laurent, Heidemarie K; Powers, Sally I; Granger, Douglas A

    2013-07-02

    This study investigated associations among young adults' hypothalamic-pituitary-adrenal axis activity, autonomic nervous system activity, and subjective stress in response to interpersonal conflict to better characterize coordination across stress systems. Seven saliva samples were collected from 199 young adult opposite-sex couples before, during, and after they discussed an unresolved relationship conflict. Samples were later assayed for cortisol and alpha-amylase (sAA). Couples rated anticipatory stress prior to the conflict and perceived stress immediately following the task. Growth curve modeling was used to examine two possible levels of within-person coordination across physiological systems: alignment between cortisol and sAA responses throughout the sampling period ("matched phase coordination"), and association between overall levels of cortisol and sAA in response to conflict ("average level coordination"). Whereas both partners showed the former type of coordination, only women showed the latter type. Positive anticipation of the stressor predicted stronger cortisol-sAA matched phase coordination for women. Pre-task ratings related to women's sAA, and post-task ratings related to both partners' cortisol responses. Implications for a multisystem interpretation of normal and pathological responses to daily stress are discussed. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Refining the multisystem view of the stress response: Coordination among cortisol, alpha-amylase, and subjective stress in response to relationship conflict

    Science.gov (United States)

    Powers, Sally I.; Granger, Douglas A.

    2013-01-01

    This study investigated associations among young adults' hypothalamic-pituitary-adrenal axis activity, autonomic nervous system activity, and subjective stress in response to interpersonal conflict to better characterize coordination across stress systems. Seven saliva samples were collected from 199 young adult opposite-sex couples before, during, and after they discussed an unresolved relationship conflict. Samples were later assayed for cortisol and alpha-amylase (sAA). Couples rated anticipatory stress prior to the conflict and perceived stress immediately following the task. Growth curve modeling was used to examine two possible levels of within-person coordination across physiological systems: alignment between cortisol and sAA responses throughout the sampling period (“matched phase coordination”), and association between overall levels of cortisol and sAA in response to conflict (“average level coordination”). Whereas both partners showed the former type of coordination, only women showed the latter type. Positive anticipation of the stressor predicted stronger cortisol-sAA matched phase coordination for women. Pre-task ratings related to women's sAA, and post-task ratings related to both partners' cortisol responses. Implications for a multisystem interpretation of normal and pathological responses to daily stress are discussed. PMID:23684904

  18. Reduced Synapse and Axon Numbers in the Prefrontal Cortex of Rats Subjected to a Chronic Stress Model for Depression

    Science.gov (United States)

    Csabai, Dávid; Wiborg, Ove; Czéh, Boldizsár

    2018-01-01

    Stressful experiences can induce structural changes in neurons of the limbic system. These cellular changes contribute to the development of stress-induced psychopathologies like depressive disorders. In the prefrontal cortex of chronically stressed animals, reduced dendritic length and spine loss have been reported. This loss of dendritic material should consequently result in synapse loss as well, because of the reduced dendritic surface. But so far, no one studied synapse numbers in the prefrontal cortex of chronically stressed animals. Here, we examined synaptic contacts in rats subjected to an animal model for depression, where animals are exposed to a chronic stress protocol. Our hypothesis was that long term stress should reduce the number of axo-spinous synapses in the medial prefrontal cortex. Adult male rats were exposed to daily stress for 9 weeks and afterward we did a post mortem quantitative electron microscopic analysis to quantify the number and morphology of synapses in the infralimbic cortex. We analyzed asymmetric (Type I) and symmetric (Type II) synapses in all cortical layers in control and stressed rats. We also quantified axon numbers and measured the volume of the infralimbic cortex. In our systematic unbiased analysis, we examined 21,000 axon terminals in total. We found the following numbers in the infralimbic cortex of control rats: 1.15 × 109 asymmetric synapses, 1.06 × 108 symmetric synapses and 1.00 × 108 myelinated axons. The density of asymmetric synapses was 5.5/μm3 and the density of symmetric synapses was 0.5/μm3. Average synapse membrane length was 207 nm and the average axon terminal membrane length was 489 nm. Stress reduced the number of synapses and myelinated axons in the deeper cortical layers, while synapse membrane lengths were increased. These stress-induced ultrastructural changes indicate that neurons of the infralimbic cortex have reduced cortical network connectivity. Such reduced network connectivity is likely

  19. Reduced Synapse and Axon Numbers in the Prefrontal Cortex of Rats Subjected to a Chronic Stress Model for Depression

    Directory of Open Access Journals (Sweden)

    Dávid Csabai

    2018-01-01

    Full Text Available Stressful experiences can induce structural changes in neurons of the limbic system. These cellular changes contribute to the development of stress-induced psychopathologies like depressive disorders. In the prefrontal cortex of chronically stressed animals, reduced dendritic length and spine loss have been reported. This loss of dendritic material should consequently result in synapse loss as well, because of the reduced dendritic surface. But so far, no one studied synapse numbers in the prefrontal cortex of chronically stressed animals. Here, we examined synaptic contacts in rats subjected to an animal model for depression, where animals are exposed to a chronic stress protocol. Our hypothesis was that long term stress should reduce the number of axo-spinous synapses in the medial prefrontal cortex. Adult male rats were exposed to daily stress for 9 weeks and afterward we did a post mortem quantitative electron microscopic analysis to quantify the number and morphology of synapses in the infralimbic cortex. We analyzed asymmetric (Type I and symmetric (Type II synapses in all cortical layers in control and stressed rats. We also quantified axon numbers and measured the volume of the infralimbic cortex. In our systematic unbiased analysis, we examined 21,000 axon terminals in total. We found the following numbers in the infralimbic cortex of control rats: 1.15 × 109 asymmetric synapses, 1.06 × 108 symmetric synapses and 1.00 × 108 myelinated axons. The density of asymmetric synapses was 5.5/μm3 and the density of symmetric synapses was 0.5/μm3. Average synapse membrane length was 207 nm and the average axon terminal membrane length was 489 nm. Stress reduced the number of synapses and myelinated axons in the deeper cortical layers, while synapse membrane lengths were increased. These stress-induced ultrastructural changes indicate that neurons of the infralimbic cortex have reduced cortical network connectivity. Such reduced network

  20. Optical scatterometry system for detecting specific line edge roughness of resist gratings subjected to detector noises

    International Nuclear Information System (INIS)

    Lee, Yen-Min; Li, Jia-Han; Cheng, Hsin-Hung; Wang, Fu-Min; Shen, Yu-Tian; Tsai, Kuen-Yu; Shieh, Jason J; Chen, Alek C

    2014-01-01

    The Fourier scatterometry model was used to measure the ZEP 520A electron beam resist lines with specific line edge roughness (LER). By obtaining the pupils via an objective lens, the angle-resolved diffraction spectrum was collected efficiently without additional mechanical scanning. The concavity of the pupil was considered as the weight function in specimen recognition. A series of white noises was examined in the model, and the tolerant white noise levels for different system numerical apertures (NAs) were reported. Our numerical results show that the scatterometry model of a higher NA can identify a target with a higher white noise level. Moreover, the fabricated ZEP 520A electron beam resist gratings with LER were measured by using our model, and the fitting results were matched with scanning electron microscope measurements. (paper)

  1. Specificity and generalization of attentional bias in sexual trauma victims suffering from posttraumatic stress disorder

    NARCIS (Netherlands)

    Fleurkens, P.F.T.; Rinck, M.; Minnen, A. van

    2011-01-01

    The present study investigated specificity of attentional biases for trauma-related stimuli using an Emotional Stroop Task. Participants were 14 women suffering from posttraumatic stress disorder (PTSD) who had experienced a sexual trauma and 24 healthy non-traumatized women. They were asked to name

  2. Job Stress, Coping Strategies, and Burnout among Abuse-Specific Counselors

    Science.gov (United States)

    Wallace, Sam Loc; Lee, Jayoung; Lee, Sang Min

    2010-01-01

    The purpose of this study is to investigate whether effective coping strategies play an important role to reduce burnout levels among sexual or substance abuse counselors. The authors examined whether coping strategies mediated or moderated relations between job stress and burnout in a sample of 232 abuse-specific counselors. Results indicated…

  3. Simulation of Stress-Strain behavior for one-dimensional aluminum samples subjected to high temperature

    DEFF Research Database (Denmark)

    Bellini, Anna; Thorborg, Jesper; Hattel, Jesper

    2004-01-01

    , financed by the EU in frame work 6 and born in collaboration with the automobile and foundry industries, to fill the mentioned gap. Through a systematic analysis of experimental tests, this study aims to develop a powerful predicting tool capable of capturing stress relaxation effects through an adequate...

  4. Posttraumatic Stress Disorder, Quality of Life, and the Subjective Experience in Liver Transplant Recipients.

    Science.gov (United States)

    Paslakis, Georgios; Beckmann, Mingo; Beckebaum, Susanne; Klein, Christian; Gräf, Jan; Erim, Yesim

    2018-03-01

    A high prevalence of posttraumatic stress disorder (PTSD) symptoms among transplant recipients has been associated with a low adherence to treatment and poor survival. It is crucial to detect and prevent the development of posttraumatic stress in transplant settings. We examined the prevalence of posttraumatic stress symptoms in 3 liver transplant recipients by means of the Essen Trauma Inventory (ETI), a self-report questionnaire. The Short Form-36 was used to assess the perceived health-related quality of life. Patients were asked to indicate the most traumatic events within the context of the liver transplantation procedure. Five patients (4.9%) fulfilled the criteria for PTSD related to liver disease or transplantation (ETI score greater than 27). In these patients, diagnosis was confirmed by a structured clinical interview. Fourteen (13.6%) patients had a partial PTSD with the ETI score less than 27 and greater than 16. Posttraumatic stress symptoms were significantly associated with perceived poor physical and mental health-related quality of life. Patients reported that the physicians' disclosure of diagnosis was experienced as traumatic, followed by treatment in an intensive care unit and the liver transplantation itself. The ETI resulted in prevalence rates for PTSD comparable to previous studies in liver transplantation settings. Medical professionals requested additional training in how to deliver severe diagnoses to patients.

  5. Measuring Stress-Reducing Effects of Virtual Training Based on Subjective Response

    NARCIS (Netherlands)

    Bosse, T.; Gerritsen, C.; de Man, J.; Treur, J.

    2012-01-01

    Training to cope with negative emotions or stress is important for professionals with a high pressure job, such as police officers and military personnel. The work reported in this paper is part of a project that aims to develop a Virtual Reality based training environment for such professionals. As

  6. Gender Differences in the Psychosomatic Reactions of Students Subjected to Examination Stress

    Science.gov (United States)

    Kosmala-Anderson, Joanna; Wallace, Louise M.

    2007-01-01

    Introduction: The study investigated pre-examination anxiety and emotional control strategies as possible mediators of gender differences in self reported intensity and type of psychosomatic reactions to examination stress. Method: Sample comprised 150 male and 150 female high school senior students and university students who voluntarily…

  7. Sex Differences in Cardiovascular and Subjective Stress Reactions: Prospective Evidence in a Realistic Military Setting

    Science.gov (United States)

    2014-01-01

    this study require comment. Importantly, we did not control for menstrual phase or oral contraceptive use. Reproductive hormones may be implicated in...differences in emotional and physiological responses to the Trier Social Stress Test. J Behav Ther Exp Psychiatry 39:87–98. Kirschbaum C, Pirke KM

  8. Age Identity in Context: Stress and the Subjective Side of Aging

    Science.gov (United States)

    Schafer, Markus H.; Shippee, Tetyana Pylypiv

    2010-01-01

    The passage of time is fundamentally experienced through people's interaction with their social worlds. Life-course scholars acknowledge the multiple aspects of time-based experience but have given little attention to age identity in a dynamic context. Drawing from a stress-process model, we expected that turbulence within people's family…

  9. Behavioral stress alters corticolimbic microglia in a sex- and brain region-specific manner.

    Science.gov (United States)

    Bollinger, Justin L; Collins, Kaitlyn E; Patel, Rushi; Wellman, Cara L

    2017-01-01

    Women are more susceptible to numerous stress-linked psychological disorders (e.g., depression) characterized by dysfunction of corticolimbic brain regions critical for emotion regulation and cognitive function. Although sparsely investigated, a number of studies indicate sex differences in stress effects on neuronal structure, function, and behaviors associated with these regions. We recently demonstrated a basal sex difference in- and differential effects of stress on- microglial activation in medial prefrontal cortex (mPFC). The resident immune cells of the brain, microglia are implicated in synaptic and dendritic plasticity, and cognitive-behavioral function. Here, we examined the effects of acute (3h/day, 1 day) and chronic (3h/day, 10 days) restraint stress on microglial density and morphology, as well as immune factor expression in orbitofrontal cortex (OFC), basolateral amygdala (BLA), and dorsal hippocampus (DHC) in male and female rats. Microglia were visualized, classified based on their morphology, and stereologically counted. Microglia-associated transcripts (CD40, iNOS, Arg1, CX3CL1, CX3CR1, CD200, and CD200R) were assessed in brain punches from each region. Expression of genes linked with cellular stress, neuroimmune state, and neuron-microglia communication varied between unstressed male and female rats in a region-specific manner. In OFC, chronic stress upregulated a wider variety of immune factors in females than in males. Acute stress increased microglia-associated transcripts in BLA in males, whereas chronic stress altered immune factor expression in BLA more broadly in females. In DHC, chronic stress increased immune factor expression in males but not females. Moreover, acute and chronic stress differentially affected microglial morphological activation state in male and female rats across all brain regions investigated. In males, chronic stress altered microglial activation in a pattern consistent with microglial involvement in stress

  10. Behavioral stress alters corticolimbic microglia in a sex- and brain region-specific manner

    Science.gov (United States)

    Bollinger, Justin L.; Collins, Kaitlyn E.; Patel, Rushi

    2017-01-01

    Women are more susceptible to numerous stress-linked psychological disorders (e.g., depression) characterized by dysfunction of corticolimbic brain regions critical for emotion regulation and cognitive function. Although sparsely investigated, a number of studies indicate sex differences in stress effects on neuronal structure, function, and behaviors associated with these regions. We recently demonstrated a basal sex difference in- and differential effects of stress on- microglial activation in medial prefrontal cortex (mPFC). The resident immune cells of the brain, microglia are implicated in synaptic and dendritic plasticity, and cognitive-behavioral function. Here, we examined the effects of acute (3h/day, 1 day) and chronic (3h/day, 10 days) restraint stress on microglial density and morphology, as well as immune factor expression in orbitofrontal cortex (OFC), basolateral amygdala (BLA), and dorsal hippocampus (DHC) in male and female rats. Microglia were visualized, classified based on their morphology, and stereologically counted. Microglia-associated transcripts (CD40, iNOS, Arg1, CX3CL1, CX3CR1, CD200, and CD200R) were assessed in brain punches from each region. Expression of genes linked with cellular stress, neuroimmune state, and neuron-microglia communication varied between unstressed male and female rats in a region-specific manner. In OFC, chronic stress upregulated a wider variety of immune factors in females than in males. Acute stress increased microglia-associated transcripts in BLA in males, whereas chronic stress altered immune factor expression in BLA more broadly in females. In DHC, chronic stress increased immune factor expression in males but not females. Moreover, acute and chronic stress differentially affected microglial morphological activation state in male and female rats across all brain regions investigated. In males, chronic stress altered microglial activation in a pattern consistent with microglial involvement in stress

  11. Core subjects at the end of primary school: identifying and explaining relative strengths of children with specific language impairment (SLI)

    Science.gov (United States)

    Durkin, Kevin; Mok, Pearl L H; Conti-Ramsden, Gina

    2015-01-01

    Background In general, children with specific language impairment (SLI) tend to fall behind their typically developing (TD) peers in educational attainment. Less is known about how children with SLI fare in particular areas of the curriculum and what predicts their levels of performance. Aims To compare the distributions of performance of children with SLI in three core school subjects (English, Mathematics and Science); to test the possibility that performance would vary across the core subjects; and to examine the extent to which language impairment predicts performance. Methods & Procedures This study was conducted in England and reports historical data on educational attainments. Teacher assessment and test scores of 176 eleven-year-old children with SLI were examined in the three core subjects and compared with known national norms. Possible predictors of performance were measured, including language ability at ages 7 and 11, educational placement type, and performance IQ. Outcomes & Results Children with SLI, compared with national norms, were found to be at a disadvantage in core school subjects. Nevertheless, some children attained the levels expected of TD peers. Performance was poorest in English; relative strengths were indicated in Science and, to a lesser extent, in Mathematics. Language skills were significant predictors of performance in all three core subjects. PIQ was the strongest predictor for Mathematics. For Science, both early language skills at 7 years and PIQ made significant contributions. Conclusions & Implications Language impacts on the school performance of children with SLI, but differentially across subjects. English for these children is the most challenging of the core subjects, reflecting the high levels of language demand it incurs. Science is an area of relative strength and mathematics appears to be intermediate, arguably because some tasks in these subjects can be performed with less reliance on verbal processing. Many children

  12. Dislocation density and mechanical threshold stress in OFHC copper subjected to SHPB loading and plate impact

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Qiushi [National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang, Sichuan, 621900 (China); Zhao, Feng, E-mail: ifpzfeng@163.com [National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang, Sichuan, 621900 (China); Fu, Hua; Li, Kewu [National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang, Sichuan, 621900 (China); Liu, Fusheng [Key Laboratory of Advanced Technologies of Materials, Southwest Jiaotong University, Chengdu, Sichuan, 610031 (China)

    2017-05-17

    The dislocation density and mechanical threshold stress (MTS) of oxygen-free high-thermal-conductivity (OFHC) copper loaded at strain rates in the range of 10{sup 2} to 10{sup 6} s{sup −1} were measured. Moderate-strain-rate (10{sup 2} to 10{sup 4} s{sup −1}) experiments were performed using a Split Hopkinson Pressure Bar (SHPB). A steel collar was placed around each specimen to control the maximum loading strain. High-strain-rate (10{sup 5} to 10{sup 6} s{sup −1}) experiments were carried out using a 57-mm-bore single-stage gas gun. The radial release effect was eliminated using the momentum trapping technique. The loaded samples were recovered, and the dislocation characteristics and dislocation density were determined by X-ray diffraction profile analysis. The fraction of the screw dislocation was found to decrease with increasing loading strain and strain rate. The dislocation density was found to lie between 1.8×10{sup 14} and 2.2×10{sup 15} m{sup −2}. Quasi-static reload compression tests were performed on the recovered samples at room temperature. The mechanical threshold stress (or the flow stress at 0 K) was obtained by fitting the reload stress–strain data to the MTS model. The results of analysis of the equivalent strain, mechanical threshold stress, and dislocation density measurements suggest that the relation between the mechanical threshold stress and the dislocation density can be described well by the Taylor relationship.

  13. Oxidative stress augments toll-like receptor 8 mediated neutrophilic responses in healthy subjects

    Directory of Open Access Journals (Sweden)

    Matsunaga Kazuto

    2009-06-01

    Full Text Available Abstract Background Excessive oxidative stress has been reported to be generated in inflamed tissues and contribute to the pathogenesis of inflammatory lung diseases, exacerbations of which induced by viral infections are associated with toll-like receptor (TLR activation. Among these receptors, TLR8 has been reported as a key receptor that recognizes single-strand RNA virus. However, it remains unknown whether TLR8 signaling is potentiated by oxidative stress. The aim of this study is to examine whether oxidative stress modulates TLR8 signaling in vitro. Methods Human peripheral blood neutrophils were obtained from healthy non-smokers and stimulated with TLR 7/8 agonist imidazoquinoline resiquimod (R848 in the presence or absence of hydrogen peroxide (H2O2. Neutrophilic responses including cytokine release, superoxide production and chemotaxis were examined, and the signal transduction was also analyzed. Results Activation of TLR8, but not TLR7, augmented IL-8 release. The R848-augmented IL-8 release was significantly potentiated by pretreatment with H2O2 (p L-cysteine reversed this potentiation. The combination of H2O2 and R848 significantly potentiated NF-kB phosphorylation and IkBα degradation. The H2O2-potentiated IL-8 release was suppressed by MG-132, a proteosome inhibitor, and by dexamethasone. The expressions of TLR8, myeloid differentiation primary response gene 88 (MyD88, and tumor necrosis factor receptor-associated factor 6 (TRAF6 were not affected by H2O2. Conclusion TLR8-mediated neutrophilic responses were markedly potentiated by oxidative stress, and the potentiation was mediated by enhanced NF-kB activation. These results suggest that oxidative stress might potentiate the neutrophilic inflammation during viral infection.

  14. The Role of Personality and Subjective Exposure Experiences in Posttraumatic Stress Disorder and Depression Symptoms among Children Following Wenchuan Earthquake.

    Science.gov (United States)

    Chen, Xiacan; Xu, Jiajun; Li, Bin; Li, Na; Guo, Wanjun; Ran, Mao-Sheng; Zhang, Jun; Yang, Yanchun; Hu, Junmei

    2017-12-08

    This study aims to investigate the role of personality traits and subjective exposure experiences in posttraumatic stress disorder and depression symptoms. In Qingchuan, 21,652 children aged 7 to 15 years were assessed using face-to-face interviews one year after the Wenchuan earthquake in China. The Junior Eysenck Personality Questionnaire, a modified earthquake exposure scale, the UCLA Posttraumatic Stress Disorder Reaction Index (adolescent), and the Adolescent Depression Inventory were used to assess personality characteristics, trauma experiences, posttraumatic stress disorder and depression symptoms, respectively. The measurement was completed with 20,749 children. After adjusting for other factors by multinomial logistic regression analysis, neuroticism, having felt unable to escape from the disaster and having been trapped for a longer time were risk factors of posttraumatic stress disorder and depression symptoms. Socialization was a protective factor of them. Having felt extreme panic or fear was a risk factor of posttraumatic stress disorder symptoms. For depression symptoms, introversion and psychoticism were risk factors, and extraversion was a protective factor. This study was conducted with the largest representative sample of child survivors of a natural, devastating disaster in a developing country. These results could be useful for planning psychological intervention strategies for children and for influencing further research.

  15. Stressed out or subjective acquisition of competence – how do veterinary students see their curative work placement?

    Science.gov (United States)

    Dilly, Marc; Tipold, Andrea; Geuenich, Katja

    2016-01-01

    Veterinary studies in Germany are regulated by the Veterinary Certification Act (TAppV). The practical part of the education consists of 1,170 hours, whereby up to 850 hours can be spent on the curative work placement. A curative work placement can result in physical and psychological stress in the sense of a professional overload. It is the aim of this study to find out in what areas and to what extent competence is acquired and psychological stress exists in students during their work placement. Veterinary students (n=142) from all German education institutes participated in a voluntary online-study based on Burnout Screening Scales (BOSS) as well as a questionnaire regarding the acquisition of competence and excessive stress during the work placement (FKÜP). The distribution of values for work placement related stress show that such work placement related stress is generally slightly increased (T=60) and lies above that of occupational stresses within the normal population. Work placement related physical complaints also show a significant slight increase (T=61). A value (T=42) within the normal range was determined for the resource values. Few of the students questioned considered themselves to be excessively stressed in favour of a high subjective acquisition of competences. The largest increase regarding the acquisition of competence was noted for the areas of animal handling/restraint and application and injection techniques. In the sense of a perceived excessive demand regarding practical capabilities the areas of emergency management, surgery and medication dispensation were mentioned. With regard to the load structure and the acquisition of competence by veterinary students during their work placement, more support of the individual and a balancing of teaching/learning goals would be desirable and represents a promising approach. PMID:26958657

  16. Specific immunotherapy with allergoids in atopic subjects, hyporeactive to other vaccines.

    Science.gov (United States)

    Vargiu, G; Valcurone, G; Agostoni, A; Sacchi, G; Tassi, G C

    1986-01-01

    Allergoids comply with the therapeutic requirement to reach high doses of the injected allergen, since the modifications of the allergens cause a loss of allergenicity, though the immunogenicity is being retained. Considering that it is possible to use a starting dose 40 times higher in comparison with retard vaccines, we thought it very expedient to treat with allergoids 18 patients allergic to parietaria, and 12 patients allergic to grass pollen, who had shown no clinical improvement after immunotherapy, lasting for at least three years with retard vaccines. The therapeutic results obtained are the following: improvement in 66% of the parietaria allergic patients after the first year, and of the 72% in the second year, of the 75% of the grass pollen allergic patients after the first year and of the 83% in the second year. They can be interpreted as due to the fact that such patients are always poorly reactive to the doses of allergens commonly present in retard vaccines. On the contrary, they do react to allergoids, both due to the high amount of allergen administered, and to the fact that polymerization brings about a stronger epitopic expression matched by a higher immunogenic activity. Moreover, the data are also indicative for a good relationship between the antibody titer of antigen-specific blocking IgG and the clinical effectiveness valued by means of symptom and medication scores.

  17. Metabolic effects of dark chocolate consumption on energy, gut microbiota, and stress-related metabolism in free-living subjects.

    Science.gov (United States)

    Martin, Francois-Pierre J; Rezzi, Serge; Peré-Trepat, Emma; Kamlage, Beate; Collino, Sebastiano; Leibold, Edgar; Kastler, Jürgen; Rein, Dietrich; Fay, Laurent B; Kochhar, Sunil

    2009-12-01

    Dietary preferences influence basal human metabolism and gut microbiome activity that in turn may have long-term health consequences. The present study reports the metabolic responses of free living subjects to a daily consumption of 40 g of dark chocolate for up to 14 days. A clinical trial was performed on a population of 30 human subjects, who were classified in low and high anxiety traits using validated psychological questionnaires. Biological fluids (urine and blood plasma) were collected during 3 test days at the beginning, midtime and at the end of a 2 week study. NMR and MS-based metabonomics were employed to study global changes in metabolism due to the chocolate consumption. Human subjects with higher anxiety trait showed a distinct metabolic profile indicative of a different energy homeostasis (lactate, citrate, succinate, trans-aconitate, urea, proline), hormonal metabolism (adrenaline, DOPA, 3-methoxy-tyrosine) and gut microbial activity (methylamines, p-cresol sulfate, hippurate). Dark chocolate reduced the urinary excretion of the stress hormone cortisol and catecholamines and partially normalized stress-related differences in energy metabolism (glycine, citrate, trans-aconitate, proline, beta-alanine) and gut microbial activities (hippurate and p-cresol sulfate). The study provides strong evidence that a daily consumption of 40 g of dark chocolate during a period of 2 weeks is sufficient to modify the metabolism of free living and healthy human subjects, as per variation of both host and gut microbial metabolism.

  18. Peripheral erythrocytes decrease upon specific respiratory challenge with grass pollen allergen in sensitized mice and in human subjects.

    Directory of Open Access Journals (Sweden)

    Galateja Jordakieva

    Full Text Available BACKGROUND AND AIMS: Specific hyper-responsiveness towards an allergen and non-specific airway hyperreactivity both impair quality of life in patients with respiratory allergic diseases. We aimed to investigate cellular responses following specific and non-specific airway challenges locally and systemically in i sensitized BALB/c mice challenged with grass pollen allergen Phl p 5, and in ii grass pollen sensitized allergic rhinitis subjects undergoing specific airway challenge in the Vienna Challenge Chamber (VCC. METHODS AND RESULTS: BALB/c mice (n = 20 were intraperitoneally immunized with grass pollen allergen Phl p 5 and afterwards aerosol challenged with either the specific allergen Phl p 5 (n = 10 or the non-specific antigen ovalbumin (OVA (n = 10. A protocol for inducing allergic asthma as well as allergic rhinitis, according to the united airway concept, was used. Both groups of exposed mice showed significantly reduced physical activity after airway challenge. Specific airway challenge further resulted in goblet cell hyperplasia, enhanced mucous secretion, intrapulmonary leukocyte infiltration and lymphoid follicle formation, associated with significant expression of IL-4, IL-5 and IL-13 in splenocytes and also partially in lung tissue. Concerning circulating blood cell dynamics, we observed a significant drop of erythrocyte counts, hemoglobin and hematocrit levels in both mouse groups, challenged with allergen or OVA. A significant decrease in circulating erythrocytes and hematocrit levels after airway challenges with grass pollen allergen was also found in grass pollen sensitized human rhinitis subjects (n = 42 at the VCC. The effects on peripheral leukocyte counts in mice and humans however were opposed, possibly due to the different primary inflammation sites. CONCLUSION: Our data revealed that, besides significant leukocyte dynamics, particularly erythrocytes are involved in acute hypersensitivity reactions to respiratory allergens

  19. Effect of stress and intesity of mobile phone using on the health and subjective symptoms in GSM workers

    Directory of Open Access Journals (Sweden)

    Agata Szyjkowska

    2017-10-01

    Full Text Available Background: There are no available data on the health consequences that may result from the synergistic effects of electromagnetic fields (EMF and stress. Understanding the mechanisms of the simultaneous exposure will make it possible to develop procedures to minimize adverse health effects in professionals using mobile phones. Material and Methods: A questionnaire survey was conducted in 600 randomly selected people to obtain data on their health status and the prevalence of subjective symptoms related to the mobile phones using. Among them, there were 208 GSM Network employees, to whom the Perceived Stress Scale and Assessment of Stress at Work Questionnaire were sent. Eighty-nine completed questionnaires were returned (response rate – 42.8%. Results: The mean age of respondents was 30.3 years (standard deviation (SD = 7.7, time of occupational use of mobile phone – 4.1 years (SD = 1.7, the level of occupational stress – 95.3 (SD = 19.1. A significant percentage of people (62.8% complained of the frequent difficulties in coping with problems of everyday life, and 57.4% had a fairly frequent problems with managing their own affairs. Significant differences in the life stress were detected between groups with different time of phone use (p = 0.03, and in occupational stress level, significant differences were noted between the 2 groups differing in the length of the conversation (p = 0.05. The risk of headache, associated (odds ratio (OR = 4.2, p = 0.008 or not associated (OR = 2.97, p = 0.04 with calls on mobile phone, adjusted for stress, was significantly higher in people speaking via mobile more than 60 min/day than in those talking less. Conclusions: The study indicates that both stressors acting at the same time (EMF from cell phone and stress adversely affect the well-being of workers and increase the risk of subjective symptoms. Med Pr 2017;68(5:617–628

  20. [Effect of stress and intesity of mobile phone using on the health and subjective symptoms in GSM workers].

    Science.gov (United States)

    Szyjkowska, Agata; Gadzicka, Elżbieta; Szymczak, Wiesław; Bortkiewicz, Alicja

    2017-07-26

    There are no available data on the health consequences that may result from the synergistic effects of electromagnetic fields (EMF) and stress. Understanding the mechanisms of the simultaneous exposure will make it possible to develop procedures to minimize adverse health effects in professionals using mobile phones. A questionnaire survey was conducted in 600 randomly selected people to obtain data on their health status and the prevalence of subjective symptoms related to the mobile phones using. Among them, there were 208 GSM Network employees, to whom the Perceived Stress Scale and Assessment of Stress at Work Questionnaire were sent. Eighty-nine completed questionnaires were returned (response rate - 42.8%). The mean age of respondents was 30.3 years (standard deviation (SD) = 7.7), time of occupational use of mobile phone - 4.1 years (SD = 1.7), the level of occupational stress - 95.3 (SD = 19.1). A significant percentage of people (62.8%) complained of the frequent difficulties in coping with problems of everyday life, and 57.4% had a fairly frequent problems with managing their own affairs. Significant differences in the life stress were detected between groups with different time of phone use (p = 0.03), and in occupational stress level, significant differences were noted between the 2 groups differing in the length of the conversation (p = 0.05). The risk of headache, associated (odds ratio (OR) = 4.2, p = 0.008) or not associated (OR = 2.97, p = 0.04) with calls on mobile phone, adjusted for stress, was significantly higher in people speaking via mobile more than 60 min/day than in those talking less. The study indicates that both stressors acting at the same time (EMF from cell phone and stress) adversely affect the well-being of workers and increase the risk of subjective symptoms. Med Pr 2017;68(5):617-628. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  1. The Accuracy of 3D Optical Reconstruction and Additive Manufacturing Processes in Reproducing Detailed Subject-Specific Anatomy

    OpenAIRE

    Paolo Ferraiuoli; Jonathan C. Taylor; Emily Martin; John W. Fenner; Andrew J. Narracott

    2017-01-01

    3D reconstruction and 3D printing of subject-specific anatomy is a promising technology for supporting clinicians in the visualisation of disease progression and planning for surgical intervention. In this context, the 3D model is typically obtained from segmentation of magnetic resonance imaging (MRI), computed tomography (CT) or echocardiography images. Although these modalities allow imaging of the tissues in vivo, assessment of quality of the reconstruction is limited by the lack of a ref...

  2. Stress-specific response of the p53-Mdm2 feedback loop

    Directory of Open Access Journals (Sweden)

    Jensen Mogens H

    2010-07-01

    Full Text Available Abstract Background The p53 signalling pathway has hundreds of inputs and outputs. It can trigger cellular senescence, cell-cycle arrest and apoptosis in response to diverse stress conditions, including DNA damage, hypoxia and nutrient deprivation. Signals from all these inputs are channeled through a single node, the transcription factor p53. Yet, the pathway is flexible enough to produce different downstream gene expression patterns in response to different stresses. Results We construct a mathematical model of the negative feedback loop involving p53 and its inhibitor, Mdm2, at the core of this pathway, and use it to examine the effect of different stresses that trigger p53. In response to DNA damage, hypoxia, etc., the model exhibits a wide variety of specific output behaviour - steady states with low or high levels of p53 and Mdm2, as well as spiky oscillations with low or high average p53 levels. Conclusions We show that even a simple negative feedback loop is capable of exhibiting the kind of flexible stress-specific response observed in the p53 system. Further, our model provides a framework for predicting the differences in p53 response to different stresses and single nucleotide polymorphisms.

  3. Cadmium induces the expression of specific stress proteins in sea urchin embryos

    International Nuclear Information System (INIS)

    Roccheri, Maria Carmela; Agnello, Maria; Bonaventura, Rosa; Matranga, Valeria

    2004-01-01

    Marine organisms are highly sensitive to many environmental stresses, and consequently, the analysis of their bio-molecular responses to different stress agents is very important for the understanding of putative repair mechanisms. Sea urchin embryos represent a simple though significant model system to test how specific stress can simultaneously affect development and protein expression. Here, we used Paracentrotus lividus sea urchin embryos to study the effects of time-dependent continuous exposure to subacute/sublethal cadmium concentrations. We found that, between 15 and 24 h of exposure, the synthesis of a specific set of stress proteins (90, 72-70, 56, 28, and 25 kDa) was induced, with an increase in the rate of synthesis of 72-70 kDa (hsps), 56 kDa (hsp), and 25 kDa, which was dependent on the lengths of treatment. Recovery experiments in which cadmium was removed showed that while stress proteins continued to be synthesized, embryo development was resumed only after short lengths of exposure

  4. [Stress and night eating syndrome: a comparison study between a sample of psychiatric outpatients and healthy subjects].

    Science.gov (United States)

    Pacitti, Francesca; Maraone, Annalisa; Zazzara, Francesca; Biondi, Massimo; Caredda, Maria

    2011-01-01

    The Night Eating Syndrome (NES) is a disorder characterized by the clinical features of morning anorexia, evening hyperphagia, and insomnia with awakenings followed by nocturnal food ingestion. The core clinical feature appears to be a delay in the circadian timing of food intake. The diagnosis and early treatment of NES may represent an important means of prevention for obesity. Aims. The aim of the present study was to determine the vulnerability to develop NES between a clinical sample of patients with psychiatric disorders and a non clinical sample. We investigated a possible relation between stress and a dysfunctional eating behaviors as NES. Methods. The Night Eating Questionnaire (NEQ) has been administered to 147 psychiatric outpatients and to 531 subjects attending the University of L'Aquila. The NEQ is a questionnaire used to evaluate the prevalence of NES. The sample has been also evaluated through the Stress-related Vulnerability Scale (SVS) to measure both perceived stress and social support. Results. The 8.2% of patients scored above the diagnostic cut-off of the NEQ, compared to the 2.1% in the sample of healthy subjects. The majority of patients who had shown NEQ>25 had a diagnosis of major depressive disorder (MDD). The total scores on the NEQ were strongly associated with the SVS total score and especially with the "lack of social support" subscale. Conclusions. This study shows the increased vulnerability of NES in the sample of psychiatric patients compared to the sample of healthy subjects. The study further confirms the strong association between perceived stress, social support, altered eating behaviors and obesity.

  5. Constitutive relationships for ocean sediments subjected to stress and temperature gradients

    International Nuclear Information System (INIS)

    Davies, T.G.; Banerjee, P.K.

    1980-08-01

    The disposal of low-level nuclear wastes by burial in deep sea sediments is an option currently being considered. This report lays the groundwork for an investigation of the stability of canisters containing nuclear wastes against movement due to fluidisation of the surrounding sediments, where such fluidisation may result from thermally induced stresses. The requisite constitutive relationships for ocean sediments under stress and temperature gradients are derived from the theory of critical state soil mechanics. A parametric survey has been made of the behaviour of an element of soil in order to assess various models and the importance of the governing parameters, The formulation of a finite element algorithm is given for the solution of the sediment stability problem. (author)

  6. Integrative Analysis of Sex-Specific microRNA Networks Following Stress in Mouse Nucleus Accumbens.

    Science.gov (United States)

    Pfau, Madeline L; Purushothaman, Immanuel; Feng, Jian; Golden, Sam A; Aleyasin, Hossein; Lorsch, Zachary S; Cates, Hannah M; Flanigan, Meghan E; Menard, Caroline; Heshmati, Mitra; Wang, Zichen; Ma'ayan, Avi; Shen, Li; Hodes, Georgia E; Russo, Scott J

    2016-01-01

    Adult women are twice as likely as men to suffer from affective and anxiety disorders, although the mechanisms underlying heightened female stress susceptibility are incompletely understood. Recent findings in mouse Nucleus Accumbens (NAc) suggest a role for DNA methylation-driven sex differences in genome-wide transcriptional profiles. However, the role of another epigenetic process-microRNA (miR) regulation-has yet to be explored. We exposed male and female mice to Subchronic Variable Stress (SCVS), a stress paradigm that produces depression-like behavior in female, but not male, mice, and performed next generation mRNA and miR sequencing on NAc tissue. We applied a combination of differential expression, miR-mRNA network and functional enrichment analyses to characterize the transcriptional and post-transcriptional landscape of sex differences in NAc stress response. We find that male and female mice exhibit largely non-overlapping miR and mRNA profiles following SCVS. The two sexes also show enrichment of different molecular pathways and functions. Collectively, our results suggest that males and females mount fundamentally different transcriptional and post-transcriptional responses to SCVS and engage sex-specific molecular processes following stress. These findings have implications for the pathophysiology and treatment of stress-related disorders in women.

  7. Carcass composition of market weight pigs subjected to heat stress in utero and during finishing.

    Science.gov (United States)

    Cruzen, S M; Boddicker, R L; Graves, K L; Johnson, T P; Arkfeld, E K; Baumgard, L H; Ross, J W; Safranski, T J; Lucy, M C; Lonergan, S M

    2015-05-01

    Objectives were to investigate the effects of prolonged gestational and/or postnatal heat stress on performance and carcass composition of market weight pigs. Pregnant gilts were exposed to gestational heat stress (GHS, 28°C to 34°C, diurnal) or thermal neutral (18°C to 22°C, diurnal) conditions during the entire gestation or during the first or second half of gestation. At 14 wk of age (58 ± 5 kg), barrows were housed in heat stress (32°C, HS) or thermal neutral (21°C, TN) conditions. Feed intake and BW were recorded weekly, and body temperature parameters were monitored twice weekly until slaughter (109 ± 5 kg). Organs were removed and weighed, and loin eye area (LEA) and back fat thickness (BF) were measured after carcass chilling. Carcass sides were separated into lean, separable fat, bone, and skin components and were weighed. Moisture, lipid, and protein content were determined in the LM at the 10th rib. Data were analyzed using a split plot with random effect of dam nested within gestational treatment. Carcass measurements included HCW as a covariate to control for weight. Planned orthogonal contrast statements were used to evaluate the overall effect of GHS in the first half, second half, or any part of gestation. Gestational heat stress did not alter postnatal performance or most body temperature parameters (P > 0.10). However, ADFI in the finishing period was increased (P carcasses (P = 0.38). Carcasses from HS barrows also had less carcass separable fat (P carcasses had a greater moisture to protein ratio (P = 0.04). HS barrows also had decreased heart (P carcass composition. Chronic HS during finishing results in longer times to reach market weight and a leaner carcass once market weight is achieved.

  8. Analysis of the temperature and stress distributions in ceramic window materials subjected to microwave heating

    International Nuclear Information System (INIS)

    Ferber, M.K.; Kimrey, H.D.; Becher, P.F.

    1983-07-01

    The temperature and stress and distributions generated in ceramic materials currently employed in microwave gyrotron tube windows were determined for a variety of operating conditions. Both edge- and face-cooled windows of either polycrystalline BeO or polycrystalline Al 2 O 3 were considered. The actual analysis involved three steps. First, a computer program was used to determine the electric field distribution within the window at a given power level and frequency (TE 02 wave propagation assumed). This program was capable of describing both the radial and axial dependence of the electric field. The effects of multiple internal reflections at the various dielectric interfaces were also accounted for. Secondly, the field distribution was used to derive an expression for the heat generated per unit volume per unit time within the window due to dieletric losses. A generalized heat conduction computer code was then used to compute the temperature distribution based on the heat generation function. Third, the stresses were determined from the temperature profiles using analytical expression or a finite-element computer program. Steady-state temperature and stress profiles were computed for the face-cooled and edge-cooled windows

  9. Spectral changes in conifers subjected to air pollution and water stress: Experimental studies

    Science.gov (United States)

    Westman, Walter E.; Price, Curtis V.

    1988-01-01

    The roles of leaf anatomy, moisture and pigment content, and number of leaf layers on spectral reflectance in healthy, pollution-stressed, and water-stressed conifer needles were examined experimentally. Jeffrey pine (Pinus jeffreyi) and giant sequoia (Sequoiadendron gigantea) were exposed to ozone and acid mist treatments in fumigation chambers; red pine (Pinus resinosa) needles were artificially dried. Infrared reflectance from stacked needles rose with free water loss. In an air-drying experiment, cell volume reductions induced by loss of turgor caused near-infrared reflectance (TM band 4) to drop after most free water was lost. Under acid mist fumigation, stunting of tissue development similarly reduced band 4 reflectance. Both artificial drying and pollutant fumigation caused a blue shift of the red edge of spectral reflectance curves in conifers, attributable to chlorophyll denaturation. Thematic mapper band ratio 4/3 fell and 5/4 rose with increasing pollution stress on artificial drying. Loss of water by air-drying, freeze-drying, or oven-drying enhanced spectral features, due in part to greater scattering and reduced water absorption. Grinding of the leaf tissue further enhanced the spectral features by increasing reflecting surfaces and path length. In a leaf-stacking experiment, an asymptote in visible and infrared reflectance was reached at 7-8 needle layers of red pine.

  10. Cellular stress and innate inflammation in organ-specific autoimmunity: lessons learned from vitiligo

    Science.gov (United States)

    Harris, John E.

    2015-01-01

    Summary For decades, research in autoimmunity has focused primarily on immune contributions to disease. Yet recent studies report elevated levels of reactive oxygen species (ROS) and abnormal activation of the unfolded protein response (UPR) in cells targeted by autoimmunity, implicating cellular stress originating from the target tissue as a contributing factor. A better understanding of this contribution may help to answer important lingering questions in organ-specific autoimmunity, like what factors initiate disease, and what directs its tissue specificity. Vitiligo, an autoimmune disease of the skin, has been the focus of translational research for over 30 years, and both melanocyte stress and immune mechanisms have been thought to be mutually exclusive explanations for pathogenesis. Chemical-induced vitiligo is a unique clinical presentation that reflects the importance of environmental influences on autoimmunity, provides insight into a new paradigm linking cell stress to the immune response, and serves as a template for other autoimmune diseases. In this review I will discuss the evidence for cell stress contributions to a number of autoimmune diseases, the questions that remain, and how vitiligo, an underappreciated example of organ-specific autoimmunity, helps to answer them. PMID:26683142

  11. Violence Exposure, Posttraumatic Stress, and Subjective Well-Being in a Sample of Russian Adults: A Facebook-Based Study.

    Science.gov (United States)

    Bogolyubova, Olga; Tikhonov, Roman; Ivanov, Victor; Panicheva, Polina; Ledovaya, Yanina

    2017-03-01

    Exposure to violence has been shown to negatively affect mental health and well-being. The goal of this Facebook-based study was to describe the rates of exposure to violence in a sample of Russian adults and to assess the impact of these experiences on subjective well-being and victimization-related psychological distress. Three types of victimization were assessed: physical assault by a stranger, physical assault by someone known to victim, and nonconsensual sexual experiences. The 5-item World Health Organization Well-Being Index (WHO-5) was used to assess subjective well-being, and Primary Care PTSD Screen (PC-PTSD) was employed as an indicator of victimization-related psychological distress. Data were obtained from 6,724 Russian-speaking Facebook users. Significant levels of lifetime victimization were reported by the study participants. Lifetime physical assault by a stranger, physical assault by someone known to victim, and sexual assault were reported by 56.9%, 64.2%, and 54.1% of respondents, respectively. Respondents exposed to violence were more likely to report posttraumatic stress symptoms and lower levels of subjective well-being. Participants who were exposed to at least one type of violence were more likely to experience symptoms of traumatic stress ( U = 1,794,250.50, p violence was associated with more severe traumatic stress symptoms ( r s = .257, p violence ( t = 8.37, p violence exposure is associated with reduced well-being among Russian adults. Our findings highlight the negative impact of violence exposure on subjective well-being and underscore the necessity to develop programs addressing violence exposure in Russian populations.

  12. Drug-induced and genetic alterations in stress-responsive systems: Implications for specific addictive diseases.

    Science.gov (United States)

    Zhou, Yan; Proudnikov, Dmitri; Yuferov, Vadim; Kreek, Mary Jeanne

    2010-02-16

    From the earliest work in our laboratory, we hypothesized, and with studies conducted in both clinical research and animal models, we have shown that drugs of abuse, administered or self-administered, on a chronic basis, profoundly alter stress-responsive systems. Alterations of expression of specific genes involved in stress responsivity, with increases or decreases in mRNA levels, receptor, and neuropeptide levels, and resultant changes in hormone levels, have been documented to occur after chronic intermittent exposure to heroin, morphine, other opiates, cocaine, other stimulants, and alcohol in animal models and in human molecular genetics. The best studied of the stress-responsive systems in humans and mammalian species in general is undoubtedly the HPA axis. In addition, there are stress-responsive systems in other parts in the brain itself, and some of these include components of the HPA axis, such as CRF and CRF receptors, along with POMC gene and gene products. Several other stress-responsive systems are known to influence the HPA axis, such as the vasopressin-vasopressin receptor system. Orexin-hypocretin, acting at its receptors, may effect changes which suggest that it should be properly categorized as a stress-responsive system. However, less is known about the interactions and connectivity of some of these different neuropeptide and receptor systems, and in particular, about the possible connectivity of fast-acting (e.g., glutamate and GABA) and slow-acting (including dopamine, serotonin, and norepinephrine) neurotransmitters with each of these stress-responsive components and the resultant impact, especially in the setting of chronic exposure to drugs of abuse. Several of these stress-responsive systems and components, primarily based on our laboratory-based and human molecular genetics research of addictive diseases, will be briefly discussed in this review. Copyright 2009 Elsevier B.V. All rights reserved.

  13. High Temperature Uniaxial Compression and Stress-Relaxation Behavior of India-Specific RAFM Steel

    Science.gov (United States)

    Shah, Naimish S.; Sunil, Saurav; Sarkar, Apu

    2018-05-01

    India-specific reduced activity ferritic martensitic steel (INRAFM), a modified 9Cr-1Mo grade, has been developed by India as its own structural material for fabrication of the Indian Test Blanket Module (TBM) to be installed in the International Thermonuclear Energy Reactor (ITER). The extensive study on mechanical and physical properties of this material has been currently going on for appraisal of this material before being put to use in the ITER. High temperature compression, stress-relaxation, and strain-rate change behavior of the INRAFM steel have been investigated. The optical microscopic and scanning electron microscopic characterizations were carried out to observe the microstructural changes that occur during uniaxial compressive deformation test. Comparable true plastic stress values at 300 °C and 500 °C and a high drop in true plastic stress at 600 °C were observed during the compression test. Stress-relaxation behaviors were investigated at 500 °C, 550 °C, and 600 °C at a strain rate of 10-3 s-1. The creep properties of the steel at different temperatures were predicted from the stress-relaxation test. The Norton's stress exponent (n) was found to decrease with the increasing temperature. Using Bird-Mukherjee-Dorn relationship, the temperature-compensated normalized strain rate vs stress was plotted. The stress exponent (n) value of 10.05 was obtained from the normalized plot. The increasing nature of the strain rate sensitivity (m) with the test temperature was found from strain-rate change test. The low plastic stability with m 0.06 was observed at 600 °C. The activation volume (V *) values were obtained in the range of 100 to 300 b3. By comparing the experimental values with the literature, the rate-controlling mechanisms at the thermally activated region of high temperature were found to be the nonconservative movement of jogged screw dislocations and thermal breaking of attractive junctions.

  14. Bone growth, limb proportions and non-specific stress in archaeological populations from Croatia.

    Science.gov (United States)

    Pinhasi, R; Timpson, A; Thomas, M; Slaus, M

    2014-01-01

    The effect of environmental factors and, in particular, non-specific stress on the growth patterns of limbs and other body dimensions of children from past populations is not well understood. This study assesses whether growth of mediaeval and post-mediaeval children aged between 0-11.5 years from Adriatic (coastal) and continental Croatia varies by region and by the prevalence and type of non-specific stress. Dental ages were estimated using the Moorrees, Fanning and Hunt (MFH) scoring method. Growth of long bone diaphyses (femur, tibia, humerus, radius and ulna) was assessed by using a composite Z-score statistic (CZS). Clavicular length was measured as a proxy for upper trunk width, distal metaphyseal width of the femur was measured as a proxy for body mass and upper and lower intra-limb indices were calculated. Differences between sub-sets sampled by (a) region and (b) active vs healed non-specific stress indicators and (c) intra-limb indices were tested by Mann--Whitney U-tests and Analysis of Covariance (ANCOVA). Adriatic children attained larger dimensions-per-age than continental children. Children with healed stress lesions had larger dimensions-per-age than those with active lesions. No inter-regional difference was found in intra-limb indices. These findings highlight the complexity of growth patterns in past populations and indicate that variation in environmental conditions such as diet and differences in the nature of non-specific stress lesions both exert a significant effect on long bone growth.

  15. FEM Modeling of In-Plane Stress Distribution in Thick Brittle Coatings/Films on Ductile Substrates Subjected to Tensile Stress to Determine Interfacial Strength.

    Science.gov (United States)

    Wang, Kaishi; Zhang, Fangzhou; Bordia, Rajendra K

    2018-03-27

    The ceramic-metal interface is present in various material structures and devices that are vulnerable to failures, like cracking, which are typically due to their incompatible properties, e.g., thermal expansion mismatch. In failure of these multilayer systems, interfacial shear strength is a good measure of the robustness of interfaces, especially for planar films. There is a widely-used shear lag model and method by Agrawal and Raj to analyse and measure the interfacial shear strength of thin brittle film on ductile substrates. The use of this classical model for a type of polymer derived ceramic coatings (thickness ~18 μm) on steel substrate leads to high values of interfacial shear strength. Here, we present finite element simulations for such a coating system when it is subjected to in-plane tension. Results show that the in-plane stresses in the coating are non-uniform, i.e., varying across the thickness of the film. Therefore, they do not meet one of the basic assumptions of the classical model: uniform in-plane stress. Furthermore, effects of three significant parameters, film thickness, crack spacing, and Young's modulus, on the in-plane stress distribution have also been investigated. 'Thickness-averaged In-plane Stress' (TIS), a new failure criterion, is proposed for estimating the interfacial shear strength, which leads to a more realistic estimation of the tensile strength and interfacial shear strength of thick brittle films/coatings on ductile substrates.

  16. Subjective, Autonomic, and Endocrine Reactivity during Social Stress in Children with Social Phobia

    Science.gov (United States)

    Kramer, Martina; Seefeldt, Wiebke Lina; Heinrichs, Nina; Tuschen-Caffier, Brunna; Schmitz, Julian; Wolf, Oliver Tobias; Blechert, Jens

    2012-01-01

    Reports of exaggerated anxiety and physiological hyperreactivity to social-evaluative situations are characteristic of childhood social phobia (SP). However, laboratory research on subjective, autonomic and endocrine functioning in childhood SP is scarce, inconsistent and limited by small sample sizes, limited breadth of measurements, and the use…

  17. Whole canopy gas exchange among elite loblolly pine families subjected to drought stress

    Science.gov (United States)

    Wilson G. Hood; Michael C. Tyree; Dylan N. Dillaway; Michael A. Blazier; Mary Anne Sword Sayer

    2012-01-01

    Future climate change simulations predict that the southeastern United States will experience hydrologic patterns similar to that currently found in the Western Gulf Region, meaning, that planted elite loblolly families may be subject to drier, hotter summers (Ruosteenoja et al. 2003, Field et al. 2007). Currently, there is little research on how these fast-growing...

  18. Knee medial and lateral contact forces in a musculoskeletal model with subject-specific contact point trajectories.

    Science.gov (United States)

    Zeighami, A; Aissaoui, R; Dumas, R

    2018-03-01

    Contact point (CP) trajectory is a crucial parameter in estimating medial/lateral tibio-femoral contact forces from the musculoskeletal (MSK) models. The objective of the present study was to develop a method to incorporate the subject-specific CP trajectories into the MSK model. Ten healthy subjects performed 45 s treadmill gait trials. The subject-specific CP trajectories were constructed on the tibia and femur as a function of extension-flexion using low-dose bi-plane X-ray images during a quasi-static squat. At each extension-flexion position, the tibia and femur CPs were superimposed in the three directions on the medial side, and in the anterior-posterior and proximal-distal directions on the lateral side to form the five kinematic constraints of the knee joint. The Lagrange multipliers associated to these constraints directly yielded the medial/lateral contact forces. The results from the personalized CP trajectory model were compared against the linear CP trajectory and sphere-on-plane CP trajectory models which were adapted from the commonly used MSK models. Changing the CP trajectory had a remarkable impact on the knee kinematics and changed the medial and lateral contact forces by 1.03 BW and 0.65 BW respectively, in certain subjects. The direction and magnitude of the medial/lateral contact force were highly variable among the subjects and the medial-lateral shift of the CPs alone could not determine the increase/decrease pattern of the contact forces. The suggested kinematic constraints are adaptable to the CP trajectories derived from a variety of joint models and those experimentally measured from the 3D imaging techniques. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. Prenatal and postnatal stress and asthma in children: Temporal- and sex-specific associations.

    Science.gov (United States)

    Lee, Alison; Mathilda Chiu, Yueh-Hsiu; Rosa, Maria José; Jara, Calvin; Wright, Robert O; Coull, Brent A; Wright, Rosalind J

    2016-09-01

    Temporal- and sex-specific effects of perinatal stress have not been examined for childhood asthma. We examined associations between prenatal and/or postnatal stress and children's asthma (n = 765) and effect modification by sex in a prospective cohort study. Maternal negative life events were ascertained prenatally and postpartum. Negative life event scores were categorized as 0, 1 to 2, 3 to 4, or 5 or greater to assess exposure-response relationships. We examined effects of prenatal and postnatal stress on children's asthma by age 6 years, modeling each as independent predictors, mutually adjusting for prenatal and postnatal stress, and finally considering interactions between prenatal and postnatal stress. Effect modification by sex was examined in stratified analyses and by fitting interaction terms. When considering stress in each period independently, among boys, a dose-response relationship was evident for each level increase on the ordinal scale prenatally (odds ratio [OR], 1.38; 95% CI, 1.06-1.79; P value for trend = .03) and postnatally (OR, 1.53; 95% CI, 1.16-2.01; P value for trend = .001); among girls, only the postnatal trend was significant (OR, 1.60; 95% CI, 1.14-2.22; P value for trend = .005). Higher stress in both the prenatal and postnatal periods was associated with increased odds of receiving a diagnosis of asthma in girls (OR, 1.37; 95% CI, 0.98-1.91; Pinteraction = .07) but not boys (OR, 1.08; 95% CI, 0.82-1.42; Pinteraction = .61). Although boys were more vulnerable to stress during the prenatal period, girls were more affected by postnatal stress and cumulative stress across both periods in relation to asthma. Understanding sex and temporal differences in response to early-life stress might provide unique insight into the cause and natural history of asthma. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  20. GAS EXCHANGE IN YOUNG PLANTS OF Tabebuia aurea(Bignoniaceae Juss. SUBJECTED TO FLOODING STRESS1

    Directory of Open Access Journals (Sweden)

    Ademir Kleber Morbeck Oliveira

    2016-02-01

    Full Text Available ABSTRACT The Paratudo (Tabebuia aurea is a species occurring in the Pantanal of Miranda, Mato Grosso do Sul, Brazil, an area characterized by seasonal flooding. To evaluate the tolerance of this plant to flooding, plants aged four months were grown in flooded soil and in non-flooded soil (control group. Stomatal conductance, transpiration and CO2 assimilation were measured during the stress (48 days and recovery (11 days period, totalling 59 days. The values of stomatal conductance of the control group and stressed plants at the beginning of the flooded were 0.33 mol m-2s-1 and reached 0.02 mol m-2 s-1 (46th day at the end of this event. For the transpiration parameter, the initial rate was 3.1 mol m s-1, and the final rate reached 0.2 or 0.3 mol m-2 s-1 (47/48 th day. The initial photosynthesis rate was 8.9 mmol m-2s-1 and oscillated after the sixth day, and the rate reached zero on the 48th day. When the photosynthesis rate reached zero, the potted plants were dried, and the rate was analyzed (11th day. The following values were obtained for dried plants: stomatal conductance = 0.26 mol m-2 s-1, transpiration rate = 2.5 mol m-2 s-1 and photosynthesis rate = 7.8 mmol m-2 s-1. Flooded soil reduced photosynthesis and stomatal conductance, leading to the hypertrophy of the lenticels. These parameters recovered and after this period, and plants exhibited tolerance to flooding stress by reducing their physiological activities.

  1. Ascorbate Peroxidase and Catalase Activities and Their Genetic Regulation in Plants Subjected to Drought and Salinity Stresses

    Directory of Open Access Journals (Sweden)

    Adriano Sofo

    2015-06-01

    Full Text Available Hydrogen peroxide (H2O2, an important relatively stable non-radical reactive oxygen species (ROS is produced by normal aerobic metabolism in plants. At low concentrations, H2O2 acts as a signal molecule involved in the regulation of specific biological/physiological processes (photosynthetic functions, cell cycle, growth and development, plant responses to biotic and abiotic stresses. Oxidative stress and eventual cell death in plants can be caused by excess H2O2 accumulation. Since stress factors provoke enhanced production of H2O2 in plants, severe damage to biomolecules can be possible due to elevated and non-metabolized cellular H2O2. Plants are endowed with H2O2-metabolizing enzymes such as catalases (CAT, ascorbate peroxidases (APX, some peroxiredoxins, glutathione/thioredoxin peroxidases, and glutathione sulfo-transferases. However, the most notably distinguished enzymes are CAT and APX since the former mainly occurs in peroxisomes and does not require a reductant for catalyzing a dismutation reaction. In particular, APX has a higher affinity for H2O2 and reduces it to H2O in chloroplasts, cytosol, mitochondria and peroxisomes, as well as in the apoplastic space, utilizing ascorbate as specific electron donor. Based on recent reports, this review highlights the role of H2O2 in plants experiencing water deficit and salinity and synthesizes major outcomes of studies on CAT and APX activity and genetic regulation in drought- and salt-stressed plants.

  2. Brain aromatase and circulating corticosterone are rapidly regulated by combined acute stress and sexual interaction in a sex-specific manner.

    Science.gov (United States)

    Dickens, M J; Balthazart, J; Cornil, C A

    2012-10-01

    Neural production of 17β-oestradiol via aromatisation of testosterone may play a critical role in rapid, nongenomic regulation of physiological and behavioural processes. In brain nuclei implicated in the control of sexual behaviour, sexual or stressfull stimuli induce, respectively, a rapid inhibition or increase in preoptic aromatase activity (AA). In the present study, we tested quail that were either nonstressed or acutely stressed (15 min of restraint) immediately before sexual interaction (5 min) with stressed or nonstressed partners. We measured nuclei-specific AA changes, corresponding behavioural output, fertilisation rates and corticosterone (CORT) concentrations. In males, sexual interaction rapidly reversed stress-induced increases of AA in the medial preoptic nucleus (POM). This time scale (sexual stimuli on POM AA may actively preserve sexual behaviour despite stress exposure. We also found distinct sex differences in contextual physiological responses: males did not show any effect of partner status, whereas females responded to both their stress exposure and the male partner's stress exposure at the level of circulating CORT and AA. In addition, fertilisation rates and female CORT correlated with the male partner's exhibition of sexually aggressive behaviour, suggesting that female perception of the male can affect their physiology as much as direct stress. Overall, male reproduction appears relatively simple: sexual stimuli, irrespective of stress, drives major neural changes including rapid reversal of stress-induced changes of AA. By contrast, female reproduction appears more nuanced and context specific, with subjects responding physiologically and behaviourally to stress, the male partner's stress exposure, and female-directed male behaviour. © 2012 The Authors. Journal of Neuroendocrinology © 2012 British Society for Neuroendocrinology.

  3. Organ-specific proteomics of soybean seedlings under flooding and drought stresses.

    Science.gov (United States)

    Wang, Xin; Khodadadi, Ehsaneh; Fakheri, Baratali; Komatsu, Setsuko

    2017-06-06

    Organ-specific analyses enrich the understanding of plant growth and development under abiotic stresses. To elucidate the cellular responses in soybean seedlings exposed to flooding and drought stresses, organ-specific analysis was performed using a gel-free/label-free proteomic technique. Physiological analysis indicated that enzyme activities of alcohol dehydrogenase and delta-1-pyrroline-5-carboxylate synthase were markedly increased in leaf and root of plants treated with 6days of flooding and drought stresses, respectively. Proteins related to photosynthesis, RNA, DNA, signaling, and the tricarboxylic acid cycle were predominately affected in leaf, hypocotyl, and root in response to flooding and drought. Notably, the tricarboxylic acid cycle was suppressed in leaf and root under both stresses. Moreover, 17 proteins, including beta-glucosidase 31 and beta-amylase 5, were identified in soybean seedlings under both stresses. The protein abundances of beta-glucosidase 31 and beta-amylase 5 were increased in leaf and root under both stresses. Additionally, the gene expression of beta-amylase 5 was upregulated in leaf exposed to the flooding and drought, and the expression level was highly correlated with the protein abundance. These results suggest that beta-amylase 5 may be involved in carbohydrate mobilization to provide energy to the leaf of soybean seedlings exposed to flooding and drought. This study examined the effects of flooding and drought on soybean seedlings in different organs using a gel-free/label-free proteomic approach. Physiological responses indicated that enzyme activities of alcohol dehydrogenase and delta-1-pyrroline-5-carboxylate synthase were increased in leaf and root of soybean seedlings exposed to flooding and drought for 6days. Functional analysis of acquired protein profiles exhibited that proteins related to photosynthesis, RNA, DNA, signaling, and the tricarboxylic acid cycle were predominated affected in leaf, hypocotyl, and root

  4. Hormonal changes in the grains of rice subjected to water stress during grain filling.

    Science.gov (United States)

    Yang, J; Zhang, J; Wang, Z; Zhu, Q; Wang, W

    2001-09-01

    Lodging-resistant rice (Oryza sativa) cultivars usually show slow grain filling when nitrogen is applied in large amounts. This study investigated the possibility that a hormonal change may mediate the effect of water deficit that enhances whole plant senescence and speeds up grain filling. Two rice cultivars showing high lodging resistance and slow grain filling were field grown and applied with either normal or high amount nitrogen (HN) at heading. Well-watered and water-stressed (WS) treatments were imposed 9 days post anthesis to maturity. Results showed that WS increased partitioning of fixed (14)CO(2) into grains, accelerated the grain filling rate but shortened the grain filling period, whereas the HN did the opposite way. Cytokinin (zeatin + zeatin riboside) and indole-3-acetic acid contents in the grains transiently increased at early filling stage and WS treatments hastened their declines at the late grain filling stage. Gibberellins (GAs; GA(1) + GA(4)) in the grains were also high at early grain filling but HN enhanced, whereas WS substantially reduced, its accumulation. Opposite to GAs, abscisic acid (ABA) in the grains was low at early grain filling but WS remarkably enhanced its accumulation. The peak values of ABA were significantly correlated with the maximum grain filling rates (r = 0.92**, P water stress during grain filling, especially a decrease in GAs and an increase in ABA, enhances the remobilization of prestored carbon to the grains and accelerates the grain filling rate.

  5. Major depressive disorder mediates accelerated aging in rats subjected to chronic mild stress.

    Science.gov (United States)

    Xie, Xiaoxian; Chen, Yangyang; Ma, Lingyan; Shen, Qichen; Huang, Liangfeng; Zhao, Binggong; Wu, Tao; Fu, Zhengwei

    2017-06-30

    Major depressive disorder (MDD) has a complex etiology and is characterized by a change in mood and psychophysiological state. MDD has been shown to mediate accelerated biological aging in patients, although the underlying mechanism is not well understood. In the present study, we used a chronic mild stress (CMS) paradigm to induce anhedonia, one of the main symptoms of MDD. CMS induced depression-like symptoms in rats, including reduced sucrose preference and increased immobility time in the forced swim test. Moreover, stressed rats travelled a shorter total distance, had fewer grid line crossings, and spent less time in the outer zone in the open field test than controls. CMS altered the levels of 5-hydroxytryptophan, dopamine, and corticosterone in the serum and hippocampus (P<0.05); these rats also exhibited impaired liver function, decreased telomerase activity, and telomere shortening, which was associated with increased oxidative damage along with decreased superoxide dismutase and glutathione reductase activities. Mitochondria in CMS-treated rats showed ultrastructural damage as well as reduced DNA content and integrity. These findings provide physiological and cellular evidence that the MDD can mediate accelerated aging in rats. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Medical students' subjective ratings of stress levels and awareness of student support services about mental health.

    Science.gov (United States)

    Walter, Garry; Soh, Nerissa Li-Wey; Norgren Jaconelli, Sanna; Lampe, Lisa; Malhi, Gin S; Hunt, Glenn

    2013-06-01

    To descriptively assess medical students' concerns for their mental and emotional state, perceived need to conceal mental problems, perceived level of support at university, knowledge and use of student support services, and experience of stresses of daily life. From March to September 2011, medical students at an Australian university were invited to complete an anonymous online survey. 475 responses were received. Students rated study and examinations (48.9%), financial concerns (38.1%), isolation (19.4%) and relationship concerns (19.2%) as very or extremely stressful issues. Knowledge of available support services was high, with 90.8% indicating they were aware of the university's medical centre. Treatment rates were modest (31.7%). Students' concerns about their mental state were generally low, but one in five strongly felt they needed to conceal their emotional problems. Despite widespread awareness of appropriate support services, a large proportion of students felt they needed to conceal mental and emotional problems. Overall treatment rates for students who were greatly concerned about their mental and emotional state appeared modest, and, although comparable with those of similarly aged community populations, may reflect undertreatment. It would be appropriate for universities to address stressors identified by students. Strategies for encouraging distressed students to obtain appropriate assessment and treatment should also be explored. Those students who do seek healthcare are most likely to see a primary care physician, suggesting an important screening role for these health professionals.

  7. Effects of itopride hydrochloride on plasma gut-regulatory peptide and stress-related hormone levels in healthy human subjects.

    Science.gov (United States)

    Katagiri, Fumihiko; Shiga, Toru; Inoue, Shin; Sato, Yuhki; Itoh, Hiroki; Takeyama, Masaharu

    2006-01-01

    Itopride hydrochloride (itopride), a gastrokinetic drug, has recently been evaluated for its clinical usefulness in functional dyspepsia. We investigated effects of itopride on human plasma gastrin-, somatostatin-, motilin-, and cholecystokinin (CCK)-like immunoreactive substances (IS); adrenocorticotropic hormone (ACTH)-immunoreactive substances (IS), and cortisol under stress conditions in healthy subjects. A single administration of itopride caused significant increases in plasma somatostatin- and motilin-IS levels compared to placebo. Itopride significantly decreased plasma CCK-IS, and suppressed the ACTH-IS level compared to placebo. We hypothesize that itopride may have an accelerating gastric emptying effect, and a modulatory effect on the hypothalamo-pituitary-adrenal axis and autonomic nervous functions. These effects might be beneficial in stress-related diseases, suggesting that itopride has clinicopharmacological activities.

  8. Pilates versus general exercise effectiveness on pain and functionality in non-specific chronic low back pain subjects.

    Science.gov (United States)

    Mostagi, Fernanda Queiroz Ribeiro Cerci; Dias, Josilainne Marcelino; Pereira, Ligia Maxwell; Obara, Karen; Mazuquin, Bruno Fles; Silva, Mariana Felipe; Silva, Monica Angelica Cardoso; de Campos, Renata Rosa; Barreto, Maria Simone Tavares; Nogueira, Jéssyca Fernandes; Lima, Tarcísio Brandão; Carregaro, Rodrigo Luiz; Cardoso, Jefferson Rosa

    2015-10-01

    Low back pain (LBP) is one of the most common causes of disability, and the Pilates method has been associated with improvements in symptoms. The purpose of this study was to assess the effectiveness of the Pilates method, when compared to general exercises, on pain and functionality after eight weeks (16 sessions, 2×/week) and a follow-up of three months, in subjects with non-specific chronic low back pain (NSCLBP). A randomised controlled trial composed of 22 subjects was proposed. Subjects were allocated into two groups: the Pilates group (PG) (n = 11) and the general exercise group (GEG) (n = 11). The PG protocol was based on the Pilates method and the GEG performed exercises to manage NSCLBP. There were no differences between the groups. When analysed over time, the GEG demonstrated improvements in functionality between baseline and the end of treatment (P = .02; Cohen'sd¯ = 0.34) and baseline and follow-up (P = .04; Cohen'sd¯ = 0.31). There were no differences between the Pilates and general exercises with regard to pain and functionality in NSCLBP subjects but general exercises were better than Pilates for increasing functionality and flexibility. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Altering the sex determination pathway in Drosophila fat body modifies sex-specific stress responses.

    Science.gov (United States)

    Argue, Kathryn J; Neckameyer, Wendi S

    2014-07-01

    The stress response in Drosophila melanogaster reveals sex differences in behavior, similar to what has been observed in mammals. However, unlike mammals, the sex determination pathway in Drosophila is well established, making this an ideal system to identify factors involved in the modulation of sex-specific responses to stress. In this study, we show that the Drosophila fat body, which has been shown to be important for energy homeostasis and sex determination, is a dynamic tissue that is altered in response to stress in a sex and time-dependent manner. We manipulated the sex determination pathway in the fat body via targeted expression of transformer and transformer-2 and analyzed these animals for changes in their response to stress. In the majority of cases, manipulation of transformer or transformer-2 was able to change the physiological output in response to starvation and oxidative stress to that of the opposite sex. Our data also uncover the possibility of additional downstream targets for transformer and transformer-2 that are separate from the sex determination pathway and can influence behavioral and physiological responses. Copyright © 2014 the American Physiological Society.

  10. 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.

  11. Satellite III non-coding RNAs show distinct and stress-specific patterns of induction

    International Nuclear Information System (INIS)

    Sengupta, Sonali; Parihar, Rashmi; Ganesh, Subramaniam

    2009-01-01

    The heat shock response in human cells is associated with the transcription of satellite III repeats (SatIII) located in the 9q12 locus. Upon induction, the SatIII transcripts remain associated with the locus and recruit several transcription and splicing factors to form the nuclear stress bodies (nSBs). The nSBs are thought to modulate epigenetic changes during the heat shock response. We demonstrate here that the nSBs are induced by a variety of stressors and show stress-specific patterns of induction. While the transcription factor HSF1 is required for the induction of SatIII locus by the stressors tested, its specific role in the transcriptional process appears to be stress dependent. Our results suggest the existence of multiple transcriptional loci for the SatIII transcripts and that their activation might depend upon the type of stressors. Thus, induction of SatIII transcripts appears to be a generic response to a variety of stress conditions.

  12. Hand 'stress' arthritis in young subjects: effects of Flexiqule (pharma-standard Boswellia extract). A preliminary case report.

    Science.gov (United States)

    Belcaro, G; Feragalli, B; Cornelli, U; Dugall, M

    2015-10-22

    This case report (supplement registry study) evaluated subjects with painful 'stress' arthritis of the hand mainly localized at the joints. The patients received a suggestion to follow a rehabilitation plan (standard management; SM). A second group also used the same SM in association with the oral, pharma-standard supplement FlexiQule (Alchem) a new standardized, phytosomal preparation manufactured from the Boswellia plant, which can be used for self-management in inflammatory conditions (150 mg / 3 times daily). The two resulting registry groups included 12 subjects using SM+Flexiqule and and 11 controls (SM only). The groups were comparable. Serology showed no significant alterations: only ESR was slightly elevated (minimal elevation). After 2 weeks, the ESR was normal in the supplement group and mildly elevated in controls (p<0.05%). The decrease in hypertermic areas was greater/faster (p<0.05) in the supplement group. The identification of a working stress and the localization to the dominant hand was comparable in both groups. At 2 weeks, the decrease in pain was significantly faster and more important with the supplement (p<0.05). The hand became more usable in time and the score was better with the supplement (p<0.05). No supplemented patient had to use other drugs, while in the control group 3 subjects eventually used NSAIDs to control pain and stiffness and one used corticosteroids. In conclusion, the natural extract Flexiqule was effective in controlling work-related stress arthritis (without inflammaìtory signs) over a 2 weeks period, better than only Standard Management. More prolonged and larger studies are needed.

  13. Usefulness of an accelerated transoesophageal stress echocardiography in the preoperative evaluation of high risk severely obese subjects awaiting bariatric surgery

    Directory of Open Access Journals (Sweden)

    Tessier Michel

    2010-07-01

    Full Text Available Abstract Background Severe obesity is associated with an increased risk of coronary artery disease (CAD. Bariatric surgery is an effective procedure for long term weight management as well as reduction of comorbidities. Preoperative evaluation of cardiac operative risk may often be necessary but unfortunately standard imaging techniques are often suboptimal in these subjects. The purpose of this study was to demonstrate the feasibility, safety and utility of transesophageal dobutamine stress echocardiography (TE-DSE using an adapted accelerated dobutamine infusion protocol in severely obese subjects with comorbidities being evaluated for bariatric surgery for assessing the presence of myocardial ischemia. Methods Subjects with severe obesity [body mass index (BMI >40 kg/m2] with known or suspected CAD and being evaluated for bariatric surgery were recruited. Results Twenty subjects (9M/11F, aged 50 ± 8 years (mean ± SD, weighing 141 ± 21 kg and with a BMI of 50 ± 5 kg/m2 were enrolled in the study and underwent a TE-DSE. The accelerated dobutamine infusion protocol used was well tolerated. Eighteen (90% subjects reached their target heart rate with a mean intubation time of 13 ± 4 minutes. Mean dobutamine dose was 31.5 ± 9.9 ug/kg/min while mean atropine dose was 0.5 ± 0.3 mg. TE-DSE was well tolerated by all subjects without complications including no significant arrhythmia, hypotension or reduction in blood arterial saturation. Two subjects had abnormal TE-DSE suggestive of myocardial ischemia. All patients underwent bariatric surgery with no documented cardiovascular complications. Conclusions TE-DSE using an accelerated infusion protocol is a safe and well tolerated imaging technique for the evaluation of suspected myocardial ischemia and cardiac operative risk in severely obese patients awaiting bariatric surgery. Moreover, the absence of myocardial ischemia on TE-DSE correlates well with a low operative risk of cardiac event.

  14. Evaluation of a subject-specific, torque-driven computer simulation model of one-handed tennis backhand groundstrokes.

    Science.gov (United States)

    Kentel, Behzat B; King, Mark A; Mitchell, Sean R

    2011-11-01

    A torque-driven, subject-specific 3-D computer simulation model of the impact phase of one-handed tennis backhand strokes was evaluated by comparing performance and simulation results. Backhand strokes of an elite subject were recorded on an artificial tennis court. Over the 50-ms period after impact, good agreement was found with an overall RMS difference of 3.3° between matching simulation and performance in terms of joint and racket angles. Consistent with previous experimental research, the evaluation process showed that grip tightness and ball impact location are important factors that affect postimpact racket and arm kinematics. Associated with these factors, the model can be used for a better understanding of the eccentric contraction of the wrist extensors during one-handed backhand ground strokes, a hypothesized mechanism of tennis elbow.

  15. A Structured Review of Generic and Specific Instruments for Measuring the Subjectively Assessed Quality of Life of Seniors

    Directory of Open Access Journals (Sweden)

    Monika Kacmarova

    2015-12-01

    Full Text Available The objective of the study is to offer a review of the instruments designed for measuring the subjectively assessed quality of life of seniors. At present it is possible to notice an increase of interest in the issue of the quality of life of specific groups of population; in addition, there is a large number of tools for its measuring. The aim of the present study is to provide a systematic review of generic and specific instruments for measuring quality of life of seniors which have been published in peer-reviewed journals and whose psychometric parameters have been verified. The search procedure formed a part of a larger retrieval search in which we analyzed 4829 abstracts in EBSCO and ProQuest Central full-text databases. We found 831 instruments which claimed to be measuring quality of life and were verified their reliability or validity. We identified 3 groups of instruments suitable for use in the senior age-group: generic methodologies applicable to adults in general, 7 generic tools and 9 specific tools designed exclusively for the senior age. The paper presents the measures designed for seniors who were analyzed and compared with regard to their psychometric parameters, purpose and theoretical framework utilized for their construction. In conclusion the authors of the study provide recommendations for the use of the selected methodologies for measuring the subjectively assessed quality of life of seniors.

  16. EFFECTIVENESS OF INTEGRATED NEUROMUSCULAR INHIBITORY TECHNIQUE (INIT WITH SPECIFIC STRENGTH TRAINING EXERCISES IN SUBJECTS WITH UPPER TRAPEZIUS TRIGGER POINTS

    Directory of Open Access Journals (Sweden)

    B. Jyothirmai

    2015-10-01

    Full Text Available Background: Upper trapezius trigger points is a common cause for neck pain, decreased cervical range of motion and functional activities. The purpose of the study was to evaluate the effectiveness of integrated neuromuscular inhibitory technique (INIT along with specific strength training exercises in reducing pain, improving ROM and functional activities in subjects with upper trapezius trigger point. Methods: Thirty subjects were diagnosed with upper trapezius trigger points were included in the study. These patients were randomly allocated to intervention group (n=15, which underwent a 4- weeks training program of INIT along with specific strength training & control group (n=15 that received INIT alone. The outcome measures were taken before and after treatment. Outcomes were measured by visual analogue scale, cervical range of motion and neck disability index. Within the groups VAS, NDI, and cervical lateral flexion and rotation showed significant change in the mean value. The comparison of pre and post VAS in experimental group and control group showed a significant change in the experimental group .Paired sample t- test was used to analyze changes from before and after intervention programmed. Results: There is a statistically significant (p<0.00 improvement in both variables from baseline to 4th week in experimental group and control group but compared to control group, experimental group shows highly significant values in all parameters. Conclusion: INIT along with specific strength training is proved to be effective in reducing pain, decreasing disability and improving range of motion in individuals with upper trapezius trigger points.

  17. Cell and receptor type-specific alterations in markers of GABA neurotransmission in the prefrontal cortex of subjects with schizophrenia.

    Science.gov (United States)

    Lewis, David A; Hashimoto, Takanori; Morris, Harvey M

    2008-10-01

    Impairments in cognitive control, such as those involved in working memory, are associated with dysfunction of the dorsolateral prefrontal cortex (DLPFC) in individuals with schizophrenia. This dysfunction appears to result, at least in part, from abnormalities in GABA-mediated neurotransmission. In this paper, we review recent findings indicating that the altered DLPFC circuitry in subjects with schizophrenia reflects changes in the expression of genes that encode selective presynaptic and postsynaptic components of GABA neurotransmission. Specifically, using a combination of methods, we found that subjects with schizophrenia exhibited expression deficits in GABA-related transcripts encoding presynaptic regulators of GABA neurotransmission, neuropeptide markers of specific subpopulations of GABA neurons, and certain subunits of the GABA(A) receptor. In particular, alterations in the expression of the neuropeptide somatostatin suggested that GABA neurotransmission is impaired in the Martinotti subset of GABA neurons that target the dendrites of pyramidal cells. In contrast, none of the GABA-related transcripts assessed to date were altered in the DLPFC of monkeys chronically exposed to antipsychotic medications, suggesting that the effects observed in the human studies reflect the disease process and not its treatment. In concert with previous findings, these data suggest that working memory dysfunction in schizophrenia may be attributable to altered GABA neurotransmission in specific DLPFC microcircuits.

  18. Core subjects at the end of primary school: identifying and explaining relative strengths of children with specific language impairment (SLI).

    Science.gov (United States)

    Durkin, Kevin; Mok, Pearl L H; Conti-Ramsden, Gina

    2015-01-01

    In general, children with specific language impairment (SLI) tend to fall behind their typically developing (TD) peers in educational attainment. Less is known about how children with SLI fare in particular areas of the curriculum and what predicts their levels of performance. To compare the distributions of performance of children with SLI in three core school subjects (English, Mathematics and Science); to test the possibility that performance would vary across the core subjects; and to examine the extent to which language impairment predicts performance. This study was conducted in England and reports historical data on educational attainments. Teacher assessment and test scores of 176 eleven-year-old children with SLI were examined in the three core subjects and compared with known national norms. Possible predictors of performance were measured, including language ability at ages 7 and 11, educational placement type, and performance IQ. Children with SLI, compared with national norms, were found to be at a disadvantage in core school subjects. Nevertheless, some children attained the levels expected of TD peers. Performance was poorest in English; relative strengths were indicated in Science and, to a lesser extent, in Mathematics. Language skills were significant predictors of performance in all three core subjects. PIQ was the strongest predictor for Mathematics. For Science, both early language skills at 7 years and PIQ made significant contributions. Language impacts on the school performance of children with SLI, but differentially across subjects. English for these children is the most challenging of the core subjects, reflecting the high levels of language demand it incurs. Science is an area of relative strength and mathematics appears to be intermediate, arguably because some tasks in these subjects can be performed with less reliance on verbal processing. Many children with SLI do have the potential to reach or exceed educational targets that are set

  19. Gender Specific Association of Serum Leptin and Insulinemic Indices with Nonalcoholic Fatty Liver Disease in Prediabetic Subjects.

    Directory of Open Access Journals (Sweden)

    Israt Ara Hossain

    Full Text Available Adipose tissue-derived hormone leptin plays a functional role in glucose tolerance through its effects on insulin secretion and insulin sensitivity which also represent the risk factors for nonalcoholic fatty liver disease (NAFLD. The present study explored the gender specific association of serum leptin and insulinemic indices with NAFLD in Bangladeshi prediabetic subjects. Under a cross-sectional analytical design a total of 110 ultrasound examined prediabetic subjects, aged 25-68 years consisting of 57.3% male (55.6% non NAFLD and 44.4% NAFLD and 42.7% female (57.4% non NAFLD and 42.6% NAFLD, were investigated. Insulin secretory function (HOMA%B and insulin sensitivity (HOMA%S were calculated from homeostasis model assessment (HOMA. Serum leptin showed significant positive correlation with fasting insulin (r = 0.530, P = 0.004, postprandial insulin (r = 0.384, P = 0.042 and HOMA-IR (r = 0.541, P = 0.003 as well as significant negative correlation with HOMA%S (r = -0.388, P = 0.046 and HOMA%B (r = -0.356, P = 0.039 in male prediabetic subjects with NAFLD. In multiple linear regression analysis, log transformed leptin showed significant positive association with HOMA-IR (β = 0.706, P <0.001 after adjusting the effects of body mass index (BMI, triglyceride (TG and HOMA%B in male subjects with NAFLD. In binary logistic regression analysis, only log leptin [OR 1.29 95% (C.I (1.11-1.51, P = 0.001] in male subjects as well as HOMA%B [OR 0.94 95% (C.I (0.89-0.98, P = 0.012], HOMA-IR [OR 3.30 95% (C.I (0.99-10.95, P = 0.049] and log leptin [OR 1.10 95% (C.I (1.01-1.20, P = 0.026] in female subjects were found to be independent determinants of NAFLD after adjusting the BMI and TG. Serum leptin seems to have an association with NAFLD both in male and female prediabetic subjects and this association in turn, is mediated by insulin secretory dysfunction and insulin resistance among these subjects.

  20. Testing Specificity: Associations of Stress and Coping with Symptoms of Anxiety and Depression in Youth

    OpenAIRE

    Bettis, Alexandra H.; Forehand, Rex; McKee, Laura; Dunbar, Jennifer P.; Watson, Kelly H.; Compas, Bruce E.

    2015-01-01

    Research has documented the co-occurrence of symptoms of anxiety and depression across the lifespan, suggesting that these symptoms share common correlates and etiology. The present study aimed to examine potential specific and/or transdiagnostic correlates of symptoms of anxiety and depression in at-risk youth. The present study examined youth stress associated with parental depression and youth coping as potential correlates of symptoms of anxiety and depression in a sample of children of d...

  1. Inter-specific competitive stress does not affect the magnitude of inbreeding depression

    OpenAIRE

    Willi, Yvonne; Dietrich, Stefan; van Kleunen, Mark; Fischer, Markus

    2007-01-01

    Hypothesis: Stressful inter-specific competition enhances inbreeding depression.Organisms: Creeping spearwort (Ranunculus reptans L.) and its common competitor, thecreeping bentgrass (Agrostis stolonifera L.).Field site: Outdoor common garden experiment at the University of Potsdam.Methods: We collected plants of 12 natural populations of R. reptans differing in mean parental inbreeding coefficient (0.01–0.26). We performed within-population crosses for twogenerations and kept the offspring i...

  2. Workplace violence, psychological stress, sleep quality and subjective health in Chinese doctors: a large cross-sectional study

    Science.gov (United States)

    Sun, Tao; Gao, Lei; Li, Fujun; Shi, Yu; Xie, Fengzhe; Wang, Jinghui; Wang, Shuo; Zhang, Shue; Liu, Wenhui; Duan, Xiaojian; Liu, Xinyan; Zhang, Zhong; Li, Li; Fan, Lihua

    2017-01-01

    Background Workplace violence (WPV) against healthcare workers is known as violence in healthcare settings and referring to the violent acts that are directed towards doctors, nurses or other healthcare staff at work or on duty. Moreover, WPV can cause a large number of adverse outcomes. However, there is not enough evidence to test the link between exposure to WPV against doctors, psychological stress, sleep quality and health status in China. Objectives This study had three objectives: (1) to identify the incidence rate of WPV against doctors under a new classification, (2) to examine the association between exposure to WPV, psychological stress, sleep quality and subjective health of Chinese doctors and (3) to verify the partial mediating role of psychological stress. Design A cross-sectional online survey study. Setting The survey was conducted among 1740 doctors in tertiary hospitals, 733 in secondary hospital and 139 in primary hospital across 30 provinces of China. Participants A total of 3016 participants were invited. Ultimately, 2617 doctors completed valid questionnaires. The effective response rate was 86.8%. Results The results demonstrated that the prevalence rate of exposure to verbal abuse was the highest (76.2%), made difficulties (58.3%), smear reputation (40.8%), mobbing behaviour (40.2%), intimidation behaviour (27.6%), physical violence (24.1%) and sexual harassment (7.8%). Exposure to WPV significantly affected the psychological stress, sleep quality and self-reported health of doctors. Moreover, psychological stress partially mediated the relationship between work-related violence and health damage. Conclusion In China, most doctors have encountered various WPV from patients and their relatives. The prevalence of three new types of WPV have been investigated in our study, which have been rarely mentioned in past research. A safer work environment for Chinese healthcare workers needs to be provided to minimise health threats, which is a top

  3. Childhood adversities as specific contributors to the co-occurrence of posttraumatic stress and alcohol use disorders.

    Science.gov (United States)

    Müller, Mario; Vandeleur, Caroline; Rodgers, Stephanie; Rössler, Wulf; Castelao, Enrique; Preisig, Martin; Ajdacic-Gross, Vladeta

    2015-08-30

    There is much evidence that alcohol use disorders (AUD) often co-occur with posttraumatic stress disorders (PTSD), and that the comorbid condition is associated with a more severe clinical profile than that of PTSD without AUD. However, little is known about the role of childhood adversities as specific risk factors for the development of AUD in individuals presenting with PTSD. The aim of the study was to explore whether specific stressors from the spectrum of trauma and childhood adversities contribute to the development of AUD among subjects with PTSD. From a large community sample, of N=140 individuals with PTSD, N=24 (17.14%) received an additional diagnosis of AUD with an onset after the onset of PTSD. Those with comorbid PTSD/AUD and those with PTSD only were compared regarding type and features of their trauma, childhood adversities and psychiatric comorbidity. Compared to PTSD alone, PTSD/AUD was associated with higher levels of stress in terms of childhood adversities; in particular, sexual abuse below the age of 16, but also with having been brought up in a foster home. PTSD/AUD was also associated with an earlier age of adverse events. Treatment of AUD should include standardized assessments of trauma, especially of trauma experienced during childhood. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  4. Effect of non-alcoholic beer on Subjective Sleep Quality in a university stressed population.

    Science.gov (United States)

    Franco, L; Bravo, R; Galán, C; Rodríguez, A B; Barriga, C; Cubero, Javier

    2014-09-01

    Sleep deprivation affects the homeostasis of the physiological functions in the human organism. Beer is the only beverage that contains hops, a plant which has a sedative effect. Our objective is to determine the improvement of subjective sleep quality using the Pittsburgh Sleep Quality Index (PSQI). The sample was conducted among a population of 30 university students. The study took place during a period of 3 weeks, the first 7 days were used for the Control, and during the following 14 days the students ingested beer (were asked to drink non-alcoholic beer) while having dinner. The results revealed that Subjective Sleep Quality improved in the case of those students who drank one beer during dinner compared to the Control, this is corroborated by the fact that Sleep Latency decreased (p < 0.05) compared to their Control. The overall rating Global Score of Quality of Sleep also improved significantly (p < 0.05). These results confirm that the consumption of non-alcoholic beer at dinner time helps to improve the quality of sleep at night.

  5. Risk factors for work-related stress and subjective hardship in health-care staff in nursing homes for the elderly: A cross-sectional study.

    Science.gov (United States)

    Pélissier, Carole; Vohito, Michel; Fort, Emmanuel; Sellier, Brigitte; Agard, Jean Pierre; Fontana, Luc; Charbotel, Barbara

    2015-01-01

    This study aimed to explore potential risk factors for work-related stress by, detailing working conditions and subjective hardship according to occupational category in health-care staff working with elderly patients. A cross-sectional descriptive survey was conducted in 105 nursing homes for the elderly in France. Data on nursing home working conditions were collected by occupational physicians. The study population was limited to those in direct contact with the elderly, who were divided into 3 occupational groups defined by qualifications and tasks: housekeepers (HKs), nursing assistants (NAs) and nurses (Ns). Employees answered a questionnaire on their perceived working conditions and vocational training courses. Psychosocial stress was assessed with the Siegrist questionnaire. The subjects included 706 HKs, 1,565 NAs and 378 Ns, and the findings showed confusion of tasks and responsibilities in the study population. Verbal abuse by residents was reported by 60.9% of HKs (versus 76.2% of NAs and 76.7% of Ns, pstress related to insufficient ability, nursing home workers should be encouraged to attend job training courses, which should cover knowledge of the specific care needs of elderly patients and of the authority/responsibility required to do their job.

  6. FEM Modeling of In-Plane Stress Distribution in Thick Brittle Coatings/Films on Ductile Substrates Subjected to Tensile Stress to Determine Interfacial Strength

    Directory of Open Access Journals (Sweden)

    Kaishi Wang

    2018-03-01

    Full Text Available The ceramic-metal interface is present in various material structures and devices that are vulnerable to failures, like cracking, which are typically due to their incompatible properties, e.g., thermal expansion mismatch. In failure of these multilayer systems, interfacial shear strength is a good measure of the robustness of interfaces, especially for planar films. There is a widely-used shear lag model and method by Agrawal and Raj to analyse and measure the interfacial shear strength of thin brittle film on ductile substrates. The use of this classical model for a type of polymer derived ceramic coatings (thickness ~18 μm on steel substrate leads to high values of interfacial shear strength. Here, we present finite element simulations for such a coating system when it is subjected to in-plane tension. Results show that the in-plane stresses in the coating are non-uniform, i.e., varying across the thickness of the film. Therefore, they do not meet one of the basic assumptions of the classical model: uniform in-plane stress. Furthermore, effects of three significant parameters, film thickness, crack spacing, and Young’s modulus, on the in-plane stress distribution have also been investigated. ‘Thickness-averaged In-plane Stress’ (TIS, a new failure criterion, is proposed for estimating the interfacial shear strength, which leads to a more realistic estimation of the tensile strength and interfacial shear strength of thick brittle films/coatings on ductile substrates.

  7. Imbibition, germination and lipid mobilization response by sunflower subjected to salt stress

    International Nuclear Information System (INIS)

    Achakzai, A.K.K.

    2014-01-01

    Salinity is one of the most important abiotic stresses in arid and semi-arid regions that substantially reduce the germination, growth and average yield of major crops. The study was mainly aimed to select the most salt tolerant cultivar of sunflower. Therefore, a pot culture experiment was conducted to study the effects of four different salinity levels having electrical conductivity viz., 1.19, 9.54, 16.48 and 22.38 mS/cm on the imbibition (water uptake), germination and lipid mobilization of seedlings of 4 varieties of sunflower (Helianthus annuus L.) i.e., DO-728, DO-730, Hysun-33 and Suncross-843. Salinity levels were prepared by dissolving calculated amount of NaCl, Na/sub 2/SO/sub 4/, CaCl/sub 2/ and MgCl/sub 2/ (4:10:5:1) in half strength Hoagland culture solution. Imbibition was studied using plastic glasses at an interval of 12 and 24 hours. While germination studies were separately carried out in plastic pots and noted after every 12 hours till 20 days. Whereas, lipid contents of the salt stress germinating seeds were determined at three time intervals viz., 48, 96 and 144 hours of germination. Results showed that there was a linear decrease in imbibition, germination and lipid mobilization as the level of salinity progressively intensifies. Maximum significant reduction in imbibition (12.88%), germination (31.03%) and lipid mobilization (38.62%) is recorded in highest dose of applied salts (22.38 mS/cm). Results further exhibited that maximum significant reduction in imbibition (17.95%) and germination (43.05%) is recorded for variety Suncross-843. While minimum for the same attributes is recorded for variety DO-728. Therefore, in term of imbibitions and germination, DO-728 could be ranked as salt tolerant. Similarly maximum reduction (14.85%) in mobilized lipids is noted for DO-728 and minimum (40.89%) for DO-730. Therefore, in term of lipid mobilization, variety DO-730 could be ranked as salt tolerant and DO-728 as salt sensitive. While remaining 2

  8. Prefrontal responses to Stroop tasks in subjects with post-traumatic stress disorder assessed by functional near infrared spectroscopy

    Science.gov (United States)

    Yennu, Amarnath; Tian, Fenghua; Smith-Osborne, Alexa; J. Gatchel, Robert; Woon, Fu Lye; Liu, Hanli

    2016-07-01

    Studies on posttraumatic stress disorder (PTSD) showing attentional deficits have implicated abnormal activities in the frontal lobe. In this study, we utilized multichannel functional near-infrared spectroscopy (fNIRS) to investigate selective attention-related hemodynamic activity in the prefrontal cortex among 15 combat-exposed war-zone veterans with PTSD and 13 age- and gender-matched healthy controls. While performing the incongruent Stroop task, healthy controls showed significant activations in the left lateral prefrontal cortex (LPFC) compared to baseline readings. This observation is consistent with previously reported results. In comparison, subjects with PTSD failed to activate left LPFC during the same Stroop task. Our observations may implicate that subjects with PTSD experienced difficulty in overcoming Stroop interference. We also observed significant negative correlation between task reaction times and hemodynamic responses from left LPFC during the incongruent Stroop task in the PTSD group. Regarding the methodology used in this study, we have learned that an appropriate design of Stroop paradigms is important for meeting an optimal cognitive load which can lead to better brain image contrasts in response to Stroop interference between healthy versus PTSD subjects. Overall, the feasibility of fNIRS for studying and mapping neural correlates of selective attention and interference in subjects with PTSD is reported.

  9. Sensibility and specificity of the stress echocardiography with Dobutamine for the detection of coronary disease

    International Nuclear Information System (INIS)

    Senior, Juan Manuel; Escobar, Carlos Ignacio; Jaramillo, Mario and others

    2001-01-01

    Dobutamine stress echocardiography has become a useful method for detecting coronary artery disease in the high prevalence population. The reported sensitivity varies between 76-90% and the specificity between 60-95%. 60-95% there have been few reports regarding sensitivity and specificity among our population. The aim of this study was to evaluate the sensitivity of dopamine stress echocardiography in a population with a high probability of coronary disease. This was a randomized retrospective-prospective study. Between February 1 of 1998 and February 1 of 1999. 409 patients underwent dopamine stress echocardiography and were analyzed according to established protocol. The Dobutamine stress echocardiography as well as the angiography was checked in a blind form by one of the participating researchers trained in those procedures. The diagnostic concordance was found to be greater than 90%. Significant coronary disease was considered to be present in those cases in which there was severe stenosis greater than 50% in a major epicardial artery or greater than 40 % in the left main artery. Coronary arteriography was performed within three months of Dobutamine stress echocardiography imaging. A sixteen-segment model was used as the index for the evaluation of systolic wall thickening and the results were classified as follows: normal (l), ischemia (ll), fixed abnormality (lll) and mixed (lV). 409 patients with an average age of 62.8 +/- 12) were included in the study at random. Six patients with mediocre technical examinations were excluded. 47 % were male. 29% had a history of myocardial infarction, 35 % had a history of arterial hypertension and 10% had diabetes mellitus. The average ejection fraction was 54 +/- 13%. The examination was prescribed in order to detect the presence of ischemia in 95.8% of the cases and as part of preoperative evaluation in 4.2 %. There were adverse effects in 40% of the cases; 15% of these were systemic and 25 % cardiac. The test was

  10. Gender Specific Association of Serum Leptin and Insulinemic Indices with Nonalcoholic Fatty Liver Disease in Prediabetic Subjects.

    Science.gov (United States)

    Hossain, Israt Ara; Akter, Salima; Rahman, Mohammad Khalilur; Ali, Liaquat

    2015-01-01

    Adipose tissue-derived hormone leptin plays a functional role in glucose tolerance through its effects on insulin secretion and insulin sensitivity which also represent the risk factors for nonalcoholic fatty liver disease (NAFLD). The present study explored the gender specific association of serum leptin and insulinemic indices with NAFLD in Bangladeshi prediabetic subjects. Under a cross-sectional analytical design a total of 110 ultrasound examined prediabetic subjects, aged 25-68 years consisting of 57.3% male (55.6% non NAFLD and 44.4% NAFLD) and 42.7% female (57.4% non NAFLD and 42.6% NAFLD), were investigated. Insulin secretory function (HOMA%B) and insulin sensitivity (HOMA%S) were calculated from homeostasis model assessment (HOMA). Serum leptin showed significant positive correlation with fasting insulin (r = 0.530, P = 0.004), postprandial insulin (r = 0.384, P = 0.042) and HOMA-IR (r = 0.541, P = 0.003) as well as significant negative correlation with HOMA%S (r = -0.388, P = 0.046) and HOMA%B (r = -0.356, P = 0.039) in male prediabetic subjects with NAFLD. In multiple linear regression analysis, log transformed leptin showed significant positive association with HOMA-IR (β = 0.706, P binary logistic regression analysis, only log leptin [OR 1.29 95% (C.I) (1.11-1.51), P = 0.001] in male subjects as well as HOMA%B [OR 0.94 95% (C.I) (0.89-0.98), P = 0.012], HOMA-IR [OR 3.30 95% (C.I) (0.99-10.95), P = 0.049] and log leptin [OR 1.10 95% (C.I) (1.01-1.20), P = 0.026] in female subjects were found to be independent determinants of NAFLD after adjusting the BMI and TG. Serum leptin seems to have an association with NAFLD both in male and female prediabetic subjects and this association in turn, is mediated by insulin secretory dysfunction and insulin resistance among these subjects.

  11. Stresses, strains, and displacements in a poroelastic layered pavement model subject to a moving load

    International Nuclear Information System (INIS)

    Morshedi, C.

    1982-01-01

    The response of a layered poroelastic halfspace to a progressing normally distributed load applied at the surface is evaluated for the case in which the constant velocity of the moving load is less than that of the elastic waves in each layer. It is assumed that a steady state exists with respect to the coordinate axes attached to a moving load. A three-dimensional problem for Biot's consolidated equations is then solved by taking Fourier transforms in the horizontal directions to evaluate stresses and displacements at any point in the medium. The analysis is illustrated by numerical examples using an algorithm based on one previously developed to calculate the response to a static load for axisymmetric poroelastic layers. To reduce the amount of computation, attention is restricted to a two-dimensional problem in which the load extends infinitely in the transverse direction. Results are presented for two and three-layered pavement models composed of concrete and gravel over a clay subbase responding to moving traffic, but the method is applicable to any number of layers. The effect of varying the velocity of the load and layer properties is observed

  12. Growth and microtubule orientation of Zea mays roots subjected to osmotic stress

    Science.gov (United States)

    Blancaflor, E. B.; Hasenstein, K. H.

    1995-01-01

    Previous work has shown that microtubule (MT) reorientation follows the onset of growth inhibition on the lower side of graviresponding roots, indicating that growth reduction can occur independently of MT reorientation. To test this observation further, we examined whether the reduction in growth in response to osmotic stress is correlated with MT reorientation. The distribution and rate of growth in maize roots exposed to 350 mOsm sorbitol and KCl or 5 mM Mes/Tris buffer were measured with a digitizer. After various times roots were processed for indirect immunofluorescence microscopy. Application of sorbitol or KCl had no effect on the organization of MTs in the apical 2 mm of the root but resulted in striking and different effects in the basal region of the root. Sorbitol treatment caused rapid appearance of oval to circular holes in the microtubular array that persisted for at least 9 h. Between 30 min and 4 h of submersion in KCl, MTs in cortical cells 4 mm and farther from the quiescent center began to reorient oblique to the longitudinal axis. After 9 h, the alignment of MTs had shifted to parallel to the root axis but MTs of the epidermal cells remained transverse. In KCl-treated roots MT reorientation appeared to follow a pattern of development similar to that in controls but without elongation. Our data provide additional evidence that MT reorientation is not the cause but a consequence of growth inhibition.

  13. The stresses and displacements in cylindrical shells subject to arbitrary temperature distribution

    International Nuclear Information System (INIS)

    Tabakman, H.D.; Lin, Y.J.

    1977-01-01

    The paper begins with a statement of a reciprocal theorem in thermoelasticity based on a generalization of Betti's Reciprocal Theorem. This is followed by application to the solution of a simply supported thin walled cylindrical shell subject to arbitrary three-dimensional temperature distribution T(x,y,z). The usefulness of the theorem resides in the fact that existing solutions in elasticity may be used to obtain solutions of thermoelastic problems. This characteristic is of great importance, particularly when the temperature distribution is arbitrary, as is often the case in practise, and cannot be expressed in functional form; thus rendering solution of the thermoelastic equations very difficult. With solutions of a wide range of problems in elasticity in existence, application of the thermoelastic theorem is the key to solution of a broad class of problems in thermoelasticity, problems that cannot be solved by the classic process. (Auth.)

  14. Nature contact and organizational support during office working hours: Benefits relating to stress reduction, subjective health complaints, and sick leave.

    Science.gov (United States)

    Bjørnstad, Siv; Patil, Grete G; Raanaas, Ruth K

    2015-01-01

    Improving social support, and providing nature contact at work are potential health promoting workplace interventions. The objective was to investigate whether nature contact at work is associated with employee's health and participation, and to study whether the possible associations between nature contact and health can be explained by perceived organizational support. Data were collected through a web-based, cross-sectional survey of employees in seven public and private office workplaces in Norway (n = 707, 40% response rate). Multiple linear and logistic regression analysis were performed on 565 participants fulfilling inclusion criteria. A greater amount of indoor nature contact at work was significantly associated with less job stress (B = -0.18, CI = -0.318 to -0.042), fewer subjective health complaints (B = -0.278, CI = -0.445 to -0.112) and less sickness absence (B = -0.061, CI = -0.009 to -0.002). Perceived organizational support mediated the associations between indoor nature contact and job stress and sickness absence, and partly mediated the association with subjective health complaints. Outdoor nature contact showed no reliable association with the outcomes in this study. Extending nature contact in the physical work environment in offices, can add to the variety of possible health-promoting workplace interventions, primarily since it influences the social climate on the workplace.

  15. Quantification of the right ventricular wall using stress myocardial emission computed tomography with thallium-201 in normal subjects

    International Nuclear Information System (INIS)

    Akanabe, Hiroshi; Oshima, Motoo; Sakuma, Sadayuki; Yamamoto, Shuhei; Kawai, Naoki; Sotobata, Iwao

    1985-01-01

    Although many studies of quantitative analysis of left ventricular myocardial wall (LVMW) have been reported using stress thallium-201 (Tl-201), few reports of right ventricular myocardial wall (RVMW) have been estimated. In this study we determined whether single photon emission computed tomography (SPECT) with Tl-201 could accurately define normal range of RVMW in normal subjects. Twelve persons who have no valvular disease, nor coronary artery disease were included in this study. Stress SPECT study was reconstructed to make a short axial images of ventricles. RVMW and LVMW were flagged by mamual. Each ventricle was divided into 36 parts at every 10 degree. Relative activity counts in each ventricle were calculated as a percent counts of maximum counts in left ventricle. The normal range of RVMW with stress SPECT was as follows: anterior wall (33.2 +- 11.4 %, mean +- 2 standard deviation, -62.7 +- 18.4 %), free wall (30.1 +- 12.4 % - 38.5 +- 8.8 %), inferior wall (40.4 +- 7.8 % - 60.0 +- 21.4 %), septal wall (65.2 +- 17.2 % - 71.1 +- 14.2 %). Above the results, SPECT with Tl-201 can accurately define the normal range of RVMW, and this method is usefull to quantify the degree of ischemia and hypertrophy in RVMW. (author)

  16. Behaviour of filamentary MgB2 wires subjected to tensile stress at 4.2 K

    International Nuclear Information System (INIS)

    Kováč, P; Kopera, L; Melišek, T; Hušek, I; Rindfleisch, M; Haessler, W

    2013-01-01

    Different filamentary MgB 2 wires have been subjected to tensile stress at 4.2 K. Stress–strain and critical current versus stress and strain characteristics of wires differing by filament architecture, sheath materials, deformation and heat treatment were measured and compared. It was found that the linear increase of critical current due to the pre-compression effect (ranging from 5% up to ≈20%) is affected by thermal expansion and the strength of used metallic sheaths. The values of irreversible strain ε irr and stress σ irr depend dominantly on the applied outer sheath and its final heat treatment conditions. Consequently, the strain-tolerance of MgB 2 wires is influenced by several parameters and it is difficult to see a clear relation between I c (ε) and σ(ε) characteristics. The lowest ε irr was measured for Monel sheathed wires (0.3–0.6%), medium for GlidCop ® sheath (0.48–0.6%), and the highest ε irr = 0.6–0.9% were obtained for MgB 2 wires reinforced by the stainless steel 316L annealed at temperature between 600 and 800 ° C. The highest ε irr = 0.9% and σ irr = 900 MPa were measured for the work-hardened steel, which is not considerably softened by the heat treatment at 600 ° C/2.5 h. (paper)

  17. The Accuracy of 3D Optical Reconstruction and Additive Manufacturing Processes in Reproducing Detailed Subject-Specific Anatomy

    Directory of Open Access Journals (Sweden)

    Paolo Ferraiuoli

    2017-10-01

    Full Text Available 3D reconstruction and 3D printing of subject-specific anatomy is a promising technology for supporting clinicians in the visualisation of disease progression and planning for surgical intervention. In this context, the 3D model is typically obtained from segmentation of magnetic resonance imaging (MRI, computed tomography (CT or echocardiography images. Although these modalities allow imaging of the tissues in vivo, assessment of quality of the reconstruction is limited by the lack of a reference geometry as the subject-specific anatomy is unknown prior to image acquisition. In this work, an optical method based on 3D digital image correlation (3D-DIC techniques is used to reconstruct the shape of the surface of an ex vivo porcine heart. This technique requires two digital charge-coupled device (CCD cameras to provide full-field shape measurements and to generate a standard tessellation language (STL file of the sample surface. The aim of this work was to quantify the error of 3D-DIC shape measurements using the additive manufacturing process. The limitations of 3D printed object resolution, the discrepancy in reconstruction of the surface of cardiac soft tissue and a 3D printed model of the same surface were evaluated. The results obtained demonstrated the ability of the 3D-DIC technique to reconstruct localised and detailed features on the cardiac surface with sub-millimeter accuracy.

  18. Automatized spleen segmentation in non-contrast-enhanced MR volume data using subject-specific shape priors

    Science.gov (United States)

    Gloger, Oliver; Tönnies, Klaus; Bülow, Robin; Völzke, Henry

    2017-07-01

    To develop the first fully automated 3D spleen segmentation framework derived from T1-weighted magnetic resonance (MR) imaging data and to verify its performance for spleen delineation and volumetry. This approach considers the issue of low contrast between spleen and adjacent tissue in non-contrast-enhanced MR images. Native T1-weighted MR volume data was performed on a 1.5 T MR system in an epidemiological study. We analyzed random subsamples of MR examinations without pathologies to develop and verify the spleen segmentation framework. The framework is modularized to include different kinds of prior knowledge into the segmentation pipeline. Classification by support vector machines differentiates between five different shape types in computed foreground probability maps and recognizes characteristic spleen regions in axial slices of MR volume data. A spleen-shape space generated by training produces subject-specific prior shape knowledge that is then incorporated into a final 3D level set segmentation method. Individually adapted shape-driven forces as well as image-driven forces resulting from refined foreground probability maps steer the level set successfully to the segment the spleen. The framework achieves promising segmentation results with mean Dice coefficients of nearly 0.91 and low volumetric mean errors of 6.3%. The presented spleen segmentation approach can delineate spleen tissue in native MR volume data. Several kinds of prior shape knowledge including subject-specific 3D prior shape knowledge can be used to guide segmentation processes achieving promising results.

  19. Assessment of shear stress related parameters in the carotid bifurcation using mouse-specific FSI simulations.

    Science.gov (United States)

    De Wilde, David; Trachet, Bram; Debusschere, Nic; Iannaccone, Francesco; Swillens, Abigail; Degroote, Joris; Vierendeels, Jan; De Meyer, Guido R Y; Segers, Patrick

    2016-07-26

    The ApoE(-)(/)(-) mouse is a common small animal model to study atherosclerosis, an inflammatory disease of the large and medium sized arteries such as the carotid artery. It is generally accepted that the wall shear stress, induced by the blood flow, plays a key role in the onset of this disease. Wall shear stress, however, is difficult to derive from direct in vivo measurements, particularly in mice. In this study, we integrated in vivo imaging (micro-Computed Tomography-µCT and ultrasound) and fluid-structure interaction (FSI) modeling for the mouse-specific assessment of carotid hemodynamics and wall shear stress. Results were provided for 8 carotid bifurcations of 4 ApoE(-)(/)(-) mice. We demonstrated that accounting for the carotid elasticity leads to more realistic flow waveforms over the complete domain of the model due to volume buffering capacity in systole. The 8 simulated cases showed fairly consistent spatial distribution maps of time-averaged wall shear stress (TAWSS) and relative residence time (RRT). Zones with reduced TAWSS and elevated RRT, potential indicators of atherosclerosis-prone regions, were located mainly at the outer sinus of the external carotid artery. In contrast to human carotid hemodynamics, no flow recirculation could be observed in the carotid bifurcation region. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Maternal programming of sex-specific responses to predator odor stress in adult rats.

    Science.gov (United States)

    St-Cyr, Sophie; Abuaish, Sameera; Sivanathan, Shathveekan; McGowan, Patrick O

    2017-08-01

    Prenatal stress mediated through the mother can lead to long-term adaptations in stress-related phenotypes in offspring. This study tested the long-lasting effect of prenatal exposure to predator odor, an ethologically relevant and psychogenic stressor, in the second half of pregnancy. As adults, the offspring of predator odor-exposed mothers showed increased anxiety-like behaviors in commonly used laboratory tasks assessing novelty-induced anxiety, increased defensive behavior in males and increased ACTH stress reactivity in females in response to predator odor. Female offspring from predator odor-exposed dams showed increased transcript abundance of glucocorticoid receptor (NR3C1) on the day of birth and FK506 binding protein 5 (FKBP5) in adulthood in the amygdala. The increase in FKBP5 expression was associated with decreased DNA methylation in Fkbp5 intron V. These results indicate a sex-specific response to maternal programming by prenatal predator odor exposure and a potential epigenetic mechanism linking these responses with modifications of the stress axis in females. These results are in accordance with the mismatch hypothesis stating that an animal's response to cues within its life history reflects environmental conditions anticipated during important developmental periods and should be adaptive when these conditions are concurring. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Dynamic Parameter Identification of Subject-Specific Body Segment Parameters Using Robotics Formalism: Case Study Head Complex.

    Science.gov (United States)

    Díaz-Rodríguez, Miguel; Valera, Angel; Page, Alvaro; Besa, Antonio; Mata, Vicente

    2016-05-01

    Accurate knowledge of body segment inertia parameters (BSIP) improves the assessment of dynamic analysis based on biomechanical models, which is of paramount importance in fields such as sport activities or impact crash test. Early approaches for BSIP identification rely on the experiments conducted on cadavers or through imaging techniques conducted on living subjects. Recent approaches for BSIP identification rely on inverse dynamic modeling. However, most of the approaches are focused on the entire body, and verification of BSIP for dynamic analysis for distal segment or chain of segments, which has proven to be of significant importance in impact test studies, is rarely established. Previous studies have suggested that BSIP should be obtained by using subject-specific identification techniques. To this end, our paper develops a novel approach for estimating subject-specific BSIP based on static and dynamics identification models (SIM, DIM). We test the validity of SIM and DIM by comparing the results using parameters obtained from a regression model proposed by De Leva (1996, "Adjustments to Zatsiorsky-Seluyanov's Segment Inertia Parameters," J. Biomech., 29(9), pp. 1223-1230). Both SIM and DIM are developed considering robotics formalism. First, the static model allows the mass and center of gravity (COG) to be estimated. Second, the results from the static model are included in the dynamics equation allowing us to estimate the moment of inertia (MOI). As a case study, we applied the approach to evaluate the dynamics modeling of the head complex. Findings provide some insight into the validity not only of the proposed method but also of the application proposed by De Leva (1996, "Adjustments to Zatsiorsky-Seluyanov's Segment Inertia Parameters," J. Biomech., 29(9), pp. 1223-1230) for dynamic modeling of body segments.

  2. Neuron-specific caveolin-1 overexpression improves motor function and preserves memory in mice subjected to brain trauma.

    Science.gov (United States)

    Egawa, Junji; Schilling, Jan M; Cui, Weihua; Posadas, Edmund; Sawada, Atsushi; Alas, Basheer; Zemljic-Harpf, Alice E; Fannon-Pavlich, McKenzie J; Mandyam, Chitra D; Roth, David M; Patel, Hemal H; Patel, Piyush M; Head, Brian P

    2017-08-01

    Studies in vitro and in vivo demonstrate that membrane/lipid rafts and caveolin (Cav) organize progrowth receptors, and, when overexpressed specifically in neurons, Cav-1 augments neuronal signaling and growth and improves cognitive function in adult and aged mice; however, whether neuronal Cav-1 overexpression can preserve motor and cognitive function in the brain trauma setting is unknown. Here, we generated a neuron-targeted Cav-1-overexpressing transgenic (Tg) mouse [synapsin-driven Cav-1 (SynCav1 Tg)] and subjected it to a controlled cortical impact model of brain trauma and measured biochemical, anatomic, and behavioral changes. SynCav1 Tg mice exhibited increased hippocampal expression of Cav-1 and membrane/lipid raft localization of postsynaptic density protein 95, NMDA receptor, and tropomyosin receptor kinase B. When subjected to a controlled cortical impact, SynCav1 Tg mice demonstrated preserved hippocampus-dependent fear learning and memory, improved motor function recovery, and decreased brain lesion volume compared with wild-type controls. Neuron-targeted overexpression of Cav-1 in the adult brain prevents hippocampus-dependent learning and memory deficits, restores motor function after brain trauma, and decreases brain lesion size induced by trauma. Our findings demonstrate that neuron-targeted Cav-1 can be used as a novel therapeutic strategy to restore brain function and prevent trauma-associated maladaptive plasticity.-Egawa, J., Schilling, J. M., Cui, W., Posadas, E., Sawada, A., Alas, B., Zemljic-Harpf, A. E., Fannon-Pavlich, M. J., Mandyam, C. D., Roth, D. M., Patel, H. H., Patel, P. M., Head, B. P. Neuron-specific caveolin-1 overexpression improves motor function and preserves memory in mice subjected to brain trauma. © FASEB.

  3. Memory deficit in patients with schizophrenia and posttraumatic stress disorder: relational vs item-specific memory

    Directory of Open Access Journals (Sweden)

    Jung W

    2016-05-01

    Full Text Available Wookyoung Jung,1 Seung-Hwan Lee1,2 1Clinical Emotions and Cognition Research Laboratory, Department of Psychiatry, Inje University, Ilsan-Paik Hospital, 2Department of Psychiatry, Inje University, Ilsan-Paik Hospital, Goyang, Korea Abstract: It has been well established that patients with schizophrenia have impairments in cognitive functioning and also that patients who experienced traumatic events suffer from cognitive deficits. Of the cognitive deficits revealed in schizophrenia or posttraumatic stress disorder (PTSD patients, the current article provides a brief review of deficit in episodic memory, which is highly predictive of patients’ quality of life and global functioning. In particular, we have focused on studies that compared relational and item-specific memory performance in schizophrenia and PTSD, because measures of relational and item-specific memory are considered the most promising constructs for immediate tangible development of clinical trial paradigm. The behavioral findings of schizophrenia are based on the tasks developed by the Cognitive Neuroscience Treatment Research to Improve Cognition in Schizophrenia (CNTRICS initiative and the Cognitive Neuroscience Test Reliability and Clinical Applications for Schizophrenia (CNTRACS Consortium. The findings we reviewed consistently showed that schizophrenia and PTSD are closely associated with more severe impairments in relational memory compared to item-specific memory. Candidate brain regions involved in relational memory impairment in schizophrenia and PTSD are also discussed. Keywords: schizophrenia, posttraumatic stress disorder, episodic memory deficit, relational memory, item-specific memory, prefrontal cortex, hippocampus

  4. Grouping subjects based on conditioning criteria reveals differences in acquisition rates and in strength of conditioning-specific reflex modification.

    Science.gov (United States)

    Smith-Bell, Carrie A; Schreurs, Bernard G

    2017-11-01

    Averaging behavioral data such as the nictitating membrane response (NMR) across subjects can conceal important individual and group differences. Analyses were conducted of NMR data from rabbits that were grouped based on the point during NMR conditioning when subjects produced 8 conditioned responses (CR) in a set of 10 trials. This resulted in five groups (Early Day 1, Late Day 1, Early Day 2, Late Day 2, Early Day 3) in which group differences in CR acquisition rates were found. Percent (%) CRs were not found to increase monotonically and between-session differences in % CR were found. Conditioning-specific reflex modification (CRM) of the NMR is a type of enhanced reflexive responding of the NMR that is detected when the unconditioned stimulus (US) is presented in the absence of the conditioned stimulus (CS) following paired classical conditioning. CRM occurred in some subjects in all five groups. Subjects from both the group that was fastest and the group that was slowest to reach the learning criterion had unconditioned response (UR) topographies following NMR conditioning that strongly resembled the CR-UR response sequence elicited during NMR conditioning. This finding was most pronounced when the US duration used to assess CRM was equivalent to that used during NMR conditioning, further evidence to support the hypothesis that CRM is a CR that has generalized from the CS to the US. While grouping data based on conditioning criteria did not facilitate identifying individuals more predisposed to exhibiting CRM, strong CRM only occurred in the groups that reached the conditioning criterion the fastest. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. A thin rivulet or ridge subject to a uniform transverse shear stress at its free surface due to an external airflow

    KAUST Repository

    Sullivan, J. M.; Paterson, C.; Wilson, S. K.; Duffy, B. R.

    2012-01-01

    We use the lubrication approximation to analyze three closely related problems involving a thin rivulet or ridge (i.e., a two-dimensional droplet) of fluid subject to a prescribed uniform transverse shear stress at its free surface due

  6. Perceived social stress, pregnancy-related anxiety, depression and subjective social status among pregnant Mexican and Mexican American women in south Texas.

    Science.gov (United States)

    Fleuriet, K Jill; Sunil, T S

    2014-05-01

    The purpose of this study was to determine differences in subjective social status, perceived social stress, depressive symptoms, and pregnancy-related anxiety between pregnant Mexican American and Mexican immigrant women. Three hundred pregnant Mexican immigrant and Mexican American women in South Texas were surveyed for pregnancy-related anxiety, perceived social stress, depressive symptoms, and subjective social status. Pregnant Mexican immigrant women had higher levels of pregnancy-related anxiety and lower levels of depression and perceived social stress than pregnant Mexican American women. Change in these variables among Mexican immigrant women was relatively linear as time of residence in the United States increased. Mexican immigrant and Mexican American women had significantly different correlations between subjective social status, self-esteem and perceived social stress. Results indicate that subjective social status is an important psychosocial variable among pregnant Hispanic women. Results contribute to ongoing efforts to provide culturally responsive prenatal psychosocial support services.

  7. Sensitivity of subject-specific models to Hill muscle-tendon model parameters in simulations of gait.

    Science.gov (United States)

    Carbone, V; van der Krogt, M M; Koopman, H F J M; Verdonschot, N

    2016-06-14

    Subject-specific musculoskeletal (MS) models of the lower extremity are essential for applications such as predicting the effects of orthopedic surgery. We performed an extensive sensitivity analysis to assess the effects of potential errors in Hill muscle-tendon (MT) model parameters for each of the 56 MT parts contained in a state-of-the-art MS model. We used two metrics, namely a Local Sensitivity Index (LSI) and an Overall Sensitivity Index (OSI), to distinguish the effect of the perturbation on the predicted force produced by the perturbed MT parts and by all the remaining MT parts, respectively, during a simulated gait cycle. Results indicated that sensitivity of the model depended on the specific role of each MT part during gait, and not merely on its size and length. Tendon slack length was the most sensitive parameter, followed by maximal isometric muscle force and optimal muscle fiber length, while nominal pennation angle showed very low sensitivity. The highest sensitivity values were found for the MT parts that act as prime movers of gait (Soleus: average OSI=5.27%, Rectus Femoris: average OSI=4.47%, Gastrocnemius: average OSI=3.77%, Vastus Lateralis: average OSI=1.36%, Biceps Femoris Caput Longum: average OSI=1.06%) and hip stabilizers (Gluteus Medius: average OSI=3.10%, Obturator Internus: average OSI=1.96%, Gluteus Minimus: average OSI=1.40%, Piriformis: average OSI=0.98%), followed by the Peroneal muscles (average OSI=2.20%) and Tibialis Anterior (average OSI=1.78%) some of which were not included in previous sensitivity studies. Finally, the proposed priority list provides quantitative information to indicate which MT parts and which MT parameters should be estimated most accurately to create detailed and reliable subject-specific MS models. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Effect of body composition, aerobic performance and physical activity on exercise-induced oxidative stress in healthy subjects.

    Science.gov (United States)

    Więcek, Magdalena; Maciejczyk, Marcin; Szymura, Jadwiga; Wiecha, Szczepan; Kantorowicz, Malgorzata; Szygula, Zbigniew

    2017-01-01

    Oxidative stress could be the result of an increase in ATP resynthesis during exercise. The aim of the study was to compare prooxidant-antioxidant balance (PAB) disturbances induced by exercise at maximal intensity in young men with differing body compositions. Thirty-nine subjects were selected from 1549 volunteers aged 18-30, based on lean body mass (LBM) and body fat percentage (%BF), and then assigned into one of the following groups: control group (CON), including subjects with average LBM (59.0-64.3 kg) and average %BF (14.0-18.5%); high body fat (HBF) group, including subjects with high %BF (>21.5%) and average LBM; and high lean body mass (HLBM) group, including subjects with high LBM (>66.3 kg) and average %BF. Participants' physical activity was determined. A running test with a gradually increased load was used. Before and 3 minutes after exercise, total oxidative status (TOS) and total antioxidant capacity (TAC) were determined in the plasma, and the Oxidative Stress Index (OSI = TOS/TAC) was calculated. Maximal oxygen uptake (VO2max) was comparable in the HBF and HLBM groups (53.12±1.51 mL/kg and 50.25±1.27 mL/kg, respectively) and significantly lower compared to the CON group (58.23±1.62 mL/kg). The CON, HBF and HLBM groups showed similar significant (P0.05). There was significant negative correlation between OSI, measured before and after exercise, and participants' physical activity. There was no correlation between OSI and VO2max, BM, LBM, %BF and BMI. Exercise at maximal intensity causes a similar increase in TOS and in TAC in subjects with increased %BF and elevated content of LBM and regardless of body composition, the ratios of TOS/TAC concentrations before and after maximal-intensity exercise, have lower values in people with higher physical activity levels and are not dependent on aerobic performance (VO2max).

  9. An examination of personality, emotional intelligence, coping, gender and subjective well-being with perceived stress (trait and state) in undergraduate students.

    OpenAIRE

    Osborne, Shona Elizabeth

    2009-01-01

    This multivariate study aimed to further understand student stress. Associations between personality, emotional intelligence, coping and subjective well-being with perceived stress (trait and state) were examined in 238 undergraduate students, using self-report measures. Gender differences in these variables were also investigated. The results showed that students low in emotional stability, extraversion, emotional intelligence, subjective well-being and those with a tendency to use emotion...

  10. Quality of pharmacy-specific Medical Subject Headings (MeSH) assignment in pharmacy journals indexed in MEDLINE.

    Science.gov (United States)

    Minguet, Fernando; Salgado, Teresa M; van den Boogerd, Lucienne; Fernandez-Llimos, Fernando

    2015-01-01

    The Medical Subject Headings (MeSH) is the National Library of Medicine (NLM) controlled vocabulary for indexing articles. Inaccuracies in the MeSH thesaurus have been reported for several areas including pharmacy. To assess the quality of pharmacy-specific MeSH assignment to articles indexed in pharmacy journals. The 10 journals containing the highest number of articles published in 2012 indexed under the MeSH 'Pharmacists' were identified. All articles published over a 5-year period (2008-2012) in the 10 previously selected journals were retrieved from PubMed. MeSH terms used to index these articles were extracted and pharmacy-specific MeSH terms were identified. The frequency of use of pharmacy-specific MeSH terms was calculated across journals. A total of 6989 articles were retrieved from the 10 pharmacy journals, of which 328 (4.7%) were articles not fully indexed and therefore did not contain any MeSH terms assigned. Among the 6661 articles fully indexed, the mean number of MeSH terms was 10.1 (SD = 4.0), being 1.0 (SD = 1.3) considered as Major MeSH. Both values significantly varied across journals. The mean number of pharmacy-specific MeSH terms per article was 0.9 (SD = 1.2). A total of 3490 (52.4%) of the 6661 articles were indexed in pharmacy journals without a single pharmacy-specific MeSH. Of the total 67193 MeSH terms assigned to articles, on average 10.5% (SD = 13.9) were pharmacy-specific MeSH. A statistically significant different pattern of pharmacy-specific MeSH assignment was identified across journals (Kruskal-Wallis P journals can be improved to further enhance evidence gathering in pharmacy. Over half of the articles published in the top-10 journals publishing pharmacy literature were indexed without a single pharmacy-specific MeSH. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Real-time patient-specific finite element analysis of internal stresses in the soft tissues of a residual limb: a new tool for prosthetic fitting.

    Science.gov (United States)

    Portnoy, S; Yarnitzky, G; Yizhar, Z; Kristal, A; Oppenheim, U; Siev-Ner, I; Gefen, A

    2007-01-01

    Fitting of a prosthetic socket is a critical stage in the process of rehabilitation of a trans-tibial amputation (TTA) patient, since a misfit may cause pressure ulcers or a deep tissue injury (DTI: necrosis of the muscle flap under intact skin) in the residual limb. To date, prosthetic fitting typically depends on the subjective skills of the prosthetist, and is not supported by biomedical instrumentation that allows evaluation of the quality of fitting. Specifically, no technology is presently available to provide real-time continuous information on the internal distribution of mechanical stresses in the residual limb during fitting of the prosthesis, or while using it and this severely limits patient evaluations. In this study, a simplified yet clinically oriented patient-specific finite element (FE) model of the residual limb was developed for real-time stress analysis. For this purpose we employed a custom-made FE code that continuously calculates internal stresses in the residual limb, based on boundary conditions acquired in real-time from force sensors, located at the limb-prosthesis interface. Validation of the modeling system was accomplished by means of a synthetic phantom of the residual limb, which allowed simultaneous measurements of interface pressures and internal stresses. Human studies were conducted subsequently in five TTA patients. The dimensions of bones and soft tissues were obtained from X-rays of the residual limb of each patient. An indentation test was performed in order to obtain the effective elastic modulus of the soft tissues of the residual limb. Seven force sensors were placed between the residual limb and the prosthetic liner, and subjects walked on a treadmill during analysis. Generally, stresses under the shinbones were approximately threefold higher than stresses at the soft tissues behind the bones. Usage of a thigh corset decreased the stresses in the residual limb during gait by approximately 80%. Also, the stresses

  12. Linking salinity stress tolerance with tissue-specific Na+ sequestration in wheat roots

    Directory of Open Access Journals (Sweden)

    Honghong eWu

    2015-02-01

    Full Text Available Salinity stress tolerance is a physiologically complex trait that is conferred by the large array of interacting mechanisms. Among these, vacuolar Na+ sequestration has always been considered as one of the key components differentiating between sensitive and tolerant species and genotypes. However, vacuolar Na+ sequestration has been rarely considered in the context of the tissue-specific expression and regulation of appropriate transporters contributing to Na+ removal from the cytosol. In this work, six bread wheat varieties contrasting in their salinity tolerance (three tolerant and three sensitive were used to understand the essentiality of vacuolar Na+ sequestration between functionally different root tissues, and link it with the overall salinity stress tolerance in this species. Roots of 4-d old wheat seedlings were treated with 100 mM NaCl for 3 days, and then Na+ distribution between cytosol and vacuole was quantified by CoroNa Green fluorescent dye imaging. Our major observations were as follows: 1 salinity stress tolerance correlated positively with vacuolar Na+ sequestration ability in the mature root zone but not in the root apex; 2 Contrary to expectations, cytosolic Na+ levels in root meristem were significantly higher in salt tolerant than sensitive group, while vacuolar Na+ levels showed an opposite trend. These results are interpreted as meristem cells playing a role of the salt sensor; 3 No significant difference in the vacuolar Na+ sequestration ability was found between sensitive and tolerant group in either transition or elongation zones; 4 The overall Na+ accumulation was highest in the elongation zone, suggesting its role in osmotic adjustment and turgor maintenance required to drive root expansion growth. Overall, the reported results suggest high tissue-specificity of Na+ uptake, signalling, and sequestration in wheat root. The implications of these findings for plant breeding for salinity stress tolerance are discussed.

  13. Evaluation of dietary betaine in lactating Holstein cows subjected to heat stress.

    Science.gov (United States)

    Hall, L W; Dunshea, F R; Allen, J D; Rungruang, S; Collier, J L; Long, N M; Collier, R J

    2016-12-01

    Betaine (BET), a natural, organic osmolyte, improves cellular efficiency by acting as a chaperone, refolding denatured proteins. To test if dietary BET reduced the effect of heat stress (HS) in lactating dairy cows, multiparous, lactating Holstein cows (n=24) were blocked by days in milk (101.4±8.6 d) and randomly assigned to 1 of 3 daily intakes of dietary BET: the control (CON) group received no BET, mid intake (MID) received 57mg of BET/kg of body weight, and high dose (HI) received 114mg of BET/kg of body weight. Cows were fed twice daily and BET was top-dressed at each feeding. Cows were milked 2 times/d and milk samples were taken daily for analysis. Milk components, yield, feed intake, and water intake records were taken daily. Rectal temperature and respiration rate were taken 3 times/d at 0600, 1400, and 1800h. Cows were housed in environmentally controlled rooms and were allowed acclimation for 7d at thermoneutral (TN) conditions with a mean temperature-humidity index of 56.6. Cows were then exposed to 7d of TN followed by 7d of HS represented by a temperature-humidity index of 71.5 for 14d. This was followed by a recovery period of 3d at TN. Dietary BET increased milk yield during the TN period. No differences were found between BET and CON in total milk production or milk composition during HS. The increase in water intake during HS was not as great for cows fed BET compared with controls. The cows on CON diets had higher p.m. respiration rate than both MID and HI BET during HS, but lower rectal temperature compared with BET. No difference was found in serum glucose during TN, but cows given HI had elevated glucose levels during HS compared with CON. No differences were found in serum insulin levels between CON and BET but an intake by environment interaction was present with insulin increasing in HI-treated lactating dairy cows during HS. The heat shock response [heat shock protein (HSP) 27 and HSP70] was upregulated in bovine mammary epithelial cells

  14. Analysis of DNA methylation level by methylation-sensitive amplification polymorphism in half smooth tongue sole ( Cynoglossus semilaevis) subjected to salinity stress

    Science.gov (United States)

    Li, Siping; He, Feng; Wen, Haishen; Li, Jifang; Si, Yufeng; Liu, Mingyuan; He, Huiwen; Huang, Zhengju

    2017-04-01

    Increasingly arisen environmental constraints may contribute to heritable phenotypic variation including methylation changes, which can help the animals with development, growth and survival. In this study, we assessed the DNA methylation levels in three tissues (gonad, kidney and gill) of half smooth tongue sole under the salinity stress. The methylation-sensitive amplification polymorphism (MSAP) technique was applied to illustrate the regulation of epigenetic mechanism in environmental stimuli. Fish were subjected to 15 salinity treatment for 7 and 60 days, respectively. A total of 11259 fragments were amplified with 8 pairs of selective primers. The levels of methylated DNA in different tissues of females and males without salinity stress were analyzed, which were 32.76% and 47.32% in gonad; 38.13% and 37.69% in kidney; 37.58% and 34.96% in gill, respectively. In addition, the significant difference was observed in gonad between females and males, indicating that discrepant regulation in gonadal development and differentiation may involve sex-related genes. Further analysis showed that total and hemi-methylation were significantly decreased under 15 salinity for 7 days, probably resulting in up-regulating salt-tolerance genes expression to adjust salt changing. With the adjustment for 60 days, total and hemi-methylation prominently went back to its normal levels to obtain equilibrium. Particularly, full methylation levels were steady along with salinity stress to maintain the stability of gene expression. Additionally, the data showed that gonads in females and gills in males were superior in adaptability. As a result, DNA methylation regulates tissue- specific epiloci, and may respond to salinity stress by regulating gene expression to maintain animal survival and activity.

  15. Measuring general and specific stress causes and stress responses among beginning secondary school teachers in the Netherlands

    NARCIS (Netherlands)

    Harmsen, R; Helms-Lorenz, M.; Maulana, R; van Veen, K; van Veldhoven, M.J.P.M.

    2018-01-01

    The main aim of this study was to adjust the Questionnaire on the Experience and Evaluation of Work (QEEW) in order to measure stress causes and stress responses of beginning secondary school teachers in the Netherlands. First, the suitability of the original QEEW stress scales for use in the

  16. A root specific induction of carotenoid biosynthesis contributes to ABA production upon salt stress in arabidopsis.

    Directory of Open Access Journals (Sweden)

    M Águila Ruiz-Sola

    Full Text Available Abscisic acid (ABA is a hormone that plays a vital role in mediating abiotic stress responses in plants. Salt exposure induces the synthesis of ABA through the cleavage of carotenoid precursors (xanthophylls, which are found at very low levels in roots. Here we show that de novo ABA biosynthesis in salt-treated Arabidopsis thaliana roots involves an organ-specific induction of the carotenoid biosynthetic pathway. Upregulation of the genes encoding phytoene synthase (PSY and other enzymes of the pathway producing ABA precursors was observed in roots but not in shoots after salt exposure. A pharmacological block of the carotenoid pathway substantially reduced ABA levels in stressed roots, confirming that an increase in carotenoid accumulation contributes to fuel hormone production after salt exposure. Treatment with exogenous ABA was also found to upregulate PSY expression only in roots, suggesting an organ-specific feedback regulation of the carotenoid pathway by ABA. Taken together, our results show that the presence of high concentrations of salt in the growth medium rapidly triggers a root-specific activation of the carotenoid pathway, probably to ensure a proper supply of ABA precursors required for a sustained production of the hormone.

  17. The biologic effects of grounding the human body during sleep as measured by cortisol levels and subjective reporting of sleep, pain, and stress.

    Science.gov (United States)

    Ghaly, Maurice; Teplitz, Dale

    2004-10-01

    Diurnal cortisol secretion levels were measured and circadian cortisol profiles were evaluated in a pilot study conducted to test the hypothesis that grounding the human body to earth during sleep will result in quantifiable changes in cortisol. It was also hypothesized that grounding the human body would result in changes in sleep, pain, and stress (anxiety, depression, irritability), as measured by subjective reporting. Twelve (12) subjects with complaints of sleep dysfunction, pain, and stress were grounded to earth during sleep for 8 weeks in their own beds using a conductive mattress pad. Saliva tests were administered to establish pregrounding baseline cortisol levels. Levels were obtained at 4-hour intervals for a 24-hour period to determine the circadian cortisol profile. Cortisol testing was repeated at week 6. Subjective symptoms of sleep dysfunction, pain, and stress were reported daily throughout the 8-week test period. Measurable improvements in diurnal cortisol profiles were observed, with cortisol levels significantly reduced during night-time sleep. Subjects' 24-hour circadian cortisol profiles showed a trend toward normalization. Subjectively reported symptoms, including sleep dysfunction, pain, and stress, were reduced or eliminated in nearly all subjects. Results indicate that grounding the human body to earth ("earthing") during sleep reduces night-time levels of cortisol and resynchronizes cortisol hormone secretion more in alignment with the natural 24-hour circadian rhythm profile. Changes were most apparent in females. Furthermore, subjective reporting indicates that grounding the human body to earth during sleep improves sleep and reduces pain and stress.

  18. Workplace violence, psychological stress, sleep quality and subjective health in Chinese doctors: a large cross-sectional study.

    Science.gov (United States)

    Sun, Tao; Gao, Lei; Li, Fujun; Shi, Yu; Xie, Fengzhe; Wang, Jinghui; Wang, Shuo; Zhang, Shue; Liu, Wenhui; Duan, Xiaojian; Liu, Xinyan; Zhang, Zhong; Li, Li; Fan, Lihua

    2017-12-07

    Workplace violence (WPV) against healthcare workers is known as violence in healthcare settings and referring to the violent acts that are directed towards doctors, nurses or other healthcare staff at work or on duty. Moreover, WPV can cause a large number of adverse outcomes. However, there is not enough evidence to test the link between exposure to WPV against doctors, psychological stress, sleep quality and health status in China. This study had three objectives: (1) to identify the incidence rate of WPV against doctors under a new classification, (2) to examine the association between exposure to WPV, psychological stress, sleep quality and subjective health of Chinese doctors and (3) to verify the partial mediating role of psychological stress. A cross-sectional online survey study. The survey was conducted among 1740 doctors in tertiary hospitals, 733 in secondary hospital and 139 in primary hospital across 30 provinces of China. A total of 3016 participants were invited. Ultimately, 2617 doctors completed valid questionnaires. The effective response rate was 86.8%. The results demonstrated that the prevalence rate of exposure to verbal abuse was the highest (76.2%), made difficulties (58.3%), smear reputation (40.8%), mobbing behaviour (40.2%), intimidation behaviour (27.6%), physical violence (24.1%) and sexual harassment (7.8%). Exposure to WPV significantly affected the psychological stress, sleep quality and self-reported health of doctors. Moreover, psychological stress partially mediated the relationship between work-related violence and health damage. In China, most doctors have encountered various WPV from patients and their relatives. The prevalence of three new types of WPV have been investigated in our study, which have been rarely mentioned in past research. A safer work environment for Chinese healthcare workers needs to be provided to minimise health threats, which is a top priority for both government and society. © Article author(s) (or

  19. Pengembangan Subject Specific Pedagogy (SSP Tematik Berbasis Local Wisdom Untuk Membangun Karakter Hormat dan Kepedulian Siswa SD

    Directory of Open Access Journals (Sweden)

    Amaliyah Ulfah

    2018-01-01

    Full Text Available This study aims at generating possible thematic Subject Specific Pedagogy (SSP based on local wisdom and examining the results teachers and students perception on the pedagogical approach developed in the preliminary field testing. Drawing upon the notion of research and development by Borg & Gall, this research was conducted through different stages involving information gathering, planning, developing preliminary product, preliminary field testing, and revising. The subjects were a small group of second grade students of SD Muhammadiyah Bodon and SD Muhammadiyah Sidoarum Yogyakarta. Each consists of 10 students. The data gathering instrument consists of product validation, character observation sheets, and teacher assessment sheets. The data gathering instrument consists of product validation tool, character observation sheets, and teachers’ assessment sheets. The SSP product generated in this study consists of lesson plans, teaching materials, worksheets, and expert perception. According to the experts of media, materials, and evaluation, the SSP product is in good categories. First grade teachers result a good score to the syllabus and lesson plans, while the worksheets and evaluation are in very good category. The results from the students responses to the textbooks is 78, which is in very good category, while the students worksheets score 71 which includes in excellent category. Therefore, the developed thematic SSP based on local wisdom can be declared appropriate for use in learning.

  20. Investigation of cytokines, oxidative stress, metabolic, and inflammatory biomarkers after orange juice consumption by normal and overweight subjects

    Directory of Open Access Journals (Sweden)

    Grace K. Z. S. Dourado

    2015-10-01

    Full Text Available Background: Abdominal adiposity has been linked to metabolic abnormalities, including dyslipidemia, oxidative stress, and low-grade inflammation. Objective: To test the hypothesis that consumption of 100% orange juice (OJ would improve metabolic, oxidative, and inflammatory biomarkers and cytokine levels in normal and overweight subjects with increased waist circumference. Design: Subjects were divided into two groups in accordance with their body mass index: normal and overweight. Both groups of individuals consumed 750 mL of OJ daily for 8 weeks. Body composition (weight, height, percentage of fat mass, and waist circumference; metabolic biomarkers (total cholesterol, low-density lipoprotein-cholesterol [LDL-C], high-density lipoprotein-cholesterol [HDL-C], triglycerides, glucose, insulin, HOMA-IR, and glycated hemoglobin; oxidative biomarkers (malondialdehyde and DPPH•; inflammatory biomarkers (high-sensitivity C-reactive protein [hsCRP]; cytokines (IL-4, IL-10, IL-12, TNF-α, and IFN-γ; and diet were evaluated before and after consumption of OJ for 8 weeks. Results: The major findings of this study were: 1 no alteration in body composition in either group; 2 improvement of the lipid profile, evidenced by a reduction in total cholesterol and LDL-C; 3 a potential stimulation of the immune response due to increase in IL-12; 4 anti-inflammatory effect as a result of a marked reduction in hsCRP; and 5 antioxidant action by the enhancement of total antioxidant capacity and the reduction of lipid peroxidation, in both normal and overweight subjects. Conclusions: OJ consumption has a positive effect on important biomarkers of health status in normal and overweight subjects, thereby supporting evidence that OJ acts as functional food and could be consumed as part of a healthy diet to prevent metabolic and chronic diseases.

  1. Optimization Design of Structures Subjected to Transient Loads Using First and Second Derivatives of Dynamic Displacement and Stress

    Directory of Open Access Journals (Sweden)

    Qimao Liu

    2012-01-01

    Full Text Available This paper developed an effective optimization method, i.e., gradient-Hessian matrix-based method or second order method, of frame structures subjected to the transient loads. An algorithm of first and second derivatives of dynamic displacement and stress with respect to design variables is formulated based on the Newmark method. The inequality time-dependent constraint problem is converted into a sequence of appropriately formed time-independent unconstrained problems using the integral interior point penalty function method. The gradient and Hessian matrixes of the integral interior point penalty functions are also computed. Then the Marquardt's method is employed to solve unconstrained problems. The numerical results show that the optimal design method proposed in this paper can obtain the local optimum design of frame structures and sometimes is more efficient than the augmented Lagrange multiplier method.

  2. Accelerated reliability testing of highly aligned single-walled carbon nanotube networks subjected to DC electrical stressing.

    Science.gov (United States)

    Strus, Mark C; Chiaramonti, Ann N; Kim, Young Lae; Jung, Yung Joon; Keller, Robert R

    2011-07-01

    We investigate the electrical reliability of nanoscale lines of highly aligned, networked, metallic/semiconducting single-walled carbon nanotubes (SWCNTs) fabricated through a template-based fluidic assembly process. We find that these SWCNT networks can withstand DC current densities larger than 10 MA cm(-2) for several hours and, in some cases, several days. We develop test methods that show that the degradation rate, failure predictability and total device lifetime can be linked to the initial resistance. Scanning electron and transmission electron microscopy suggest that fabrication variability plays a critical role in the rate of degradation, and we offer an empirical method of quickly determining the long-term performance of a network. We find that well-fabricated lines subject to constant electrical stress show a linear accumulation of damage reminiscent of electromigration in metallic interconnects, and we explore the underlying physical mechanisms that could cause such behavior.

  3. Therapists' and patients' stress responses during graduated versus flooding in vivo exposure in the treatment of specific phobia: A preliminary observational study.

    Science.gov (United States)

    Schumacher, Sarah; Miller, Robert; Fehm, Lydia; Kirschbaum, Clemens; Fydrich, Thomas; Ströhle, Andreas

    2015-12-15

    Exposure therapy is considered an effective treatment strategy for phobic anxiety, however, it is rarely applied in clinical practice. The under-usage might be due to various factors of which heightened stress levels not only in patients but also in therapists are presumed to be of particular relevance. The present study aimed to investigate whether different forms of exposure might lead to varying physiological and psychological stress responses in therapists and phobic patients. 25 patients with specific phobia underwent individual cognitive behavioural therapy, performed by 25 psychotherapist trainees, applying exposure sessions in graduated form or the flooding technique. Patients and therapists provided subjective evaluations of stress and five saliva samples for analysis of salivary cortisol and alpha-amylase either during two graduated exposure sessions or during one flooding session, while a regular therapy session served as control condition. Therapists displayed heightened salivary alpha-amylase release during exposure of the flooding, but not the graduated, type. Patients showed elevated salivary cortisol during flooding exposure numerically, however, not on a statistically significant level. Therapists reported more pronounced subjective stress during flooding compared to graduated exposure. Elevated stress levels should be addressed in clinical training in order to improve application of exposure in routine practice. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  4. Ectopic expression of specific GA2 oxidase mutants promotes yield and stress tolerance in rice.

    Science.gov (United States)

    Lo, Shuen-Fang; Ho, Tuan-Hua David; Liu, Yi-Lun; Jiang, Mirng-Jier; Hsieh, Kun-Ting; Chen, Ku-Ting; Yu, Lin-Chih; Lee, Miin-Huey; Chen, Chi-Yu; Huang, Tzu-Pi; Kojima, Mikiko; Sakakibara, Hitoshi; Chen, Liang-Jwu; Yu, Su-May

    2017-07-01

    A major challenge of modern agricultural biotechnology is the optimization of plant architecture for enhanced productivity, stress tolerance and water use efficiency (WUE). To optimize plant height and tillering that directly link to grain yield in cereals and are known to be tightly regulated by gibberellins (GAs), we attenuated the endogenous levels of GAs in rice via its degradation. GA 2-oxidase (GA2ox) is a key enzyme that inactivates endogenous GAs and their precursors. We identified three conserved domains in a unique class of C 20 GA2ox, GA2ox6, which is known to regulate the architecture and function of rice plants. We mutated nine specific amino acids in these conserved domains and observed a gradient of effects on plant height. Ectopic expression of some of these GA2ox6 mutants moderately lowered GA levels and reprogrammed transcriptional networks, leading to reduced plant height, more productive tillers, expanded root system, higher WUE and photosynthesis rate, and elevated abiotic and biotic stress tolerance in transgenic rice. Combinations of these beneficial traits conferred not only drought and disease tolerance but also increased grain yield by 10-30% in field trials. Our studies hold the promise of manipulating GA levels to substantially improve plant architecture, stress tolerance and grain yield in rice and possibly in other major crops. © 2016 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  5. Isolation and characterization of a water stress-specific genomic gene, pwsi 18, from rice.

    Science.gov (United States)

    Joshee, N; Kisaka, H; Kitagawa, Y

    1998-01-01

    One of the water stress-specific cDNA clones of rice characterised previously, wsi18, was selected for further study. The wsi18 gene can be induced by water stress conditions such as mannitol, NaCl, and dryness, but not by ABA, cold, or heat. A genomic clone for wsi18, pwsi18, contained about 1.7 kbp of the 5' upstream sequence, two introns, and the full coding sequence. The 5'-upstream sequence of pwsi18 contained putative cis-acting elements, namely an ABA-responsive element (ABRE), three G-boxes, three E-boxes, a MEF-2 sequence, four direct and two inverted repeats, and four sequences similar to DRE, which is involved in the dehydration response of Arabidopsis genes. The gusA reporter gene under the control of the pwsi18 promoter showed transient expression in response to water stress. Deletion of the downstream DRE-like sequence between the distal G-boxes-2 and -3 resulted in rather low GUS expression.

  6. Comparative proteomic analysis of rats subjected to water immersion and restraint stress as an insight into gastric ulcers.

    Science.gov (United States)

    Zhou, Zheng-Rong; Huang, Pan; Song, Guang-Hao; Zhang, Zhuang; An, Ke; Lu, Han-Wen; Ju, Xiao-Li; Ding, Wei

    2017-10-01

    In the present study, comparative proteomic analysis was performed in rats subjected to water immersion‑restraint stress (WRS). A total of 26 proteins were differentially expressed and identified using matrix‑assisted laser desorption/ionization time of flight mass spectrometry. Among the 26 differentially expressed protein spots identified, 13 proteins were significantly upregulated under WRS, including pyruvate kinase and calreticulin, which may be closely associated with energy metabolism. In addition, 12 proteins were downregulated under WRS, including hemoglobin subunit β‑2 and keratin type II cytoskeletal 8, which may be important in protein metabolism and cell death. Gene Ontology analysis revealed the cellular distribution, molecular function and biological processes of the identified proteins. The mRNA levels of certain differentially expressed proteins were analyzed using fluorescence quantitative polymerase chain reaction analysis. The results of the present study aimed to offer insights into proteins, which are differentially expressed in gastric ulcers in stress, and provide theoretical evidence of a radical cure for gastric ulcers in humans.

  7. Survival and weight change among adult individuals of Periplaneta americana (Linnaeus, 1758 (Blattaria, Blattidae subject to various stress conditions

    Directory of Open Access Journals (Sweden)

    Jucelio Peter Duarte

    2015-05-01

    Full Text Available Periplaneta americana is a species of great importance to public health, since it can act as a vector of many pathogens and it reaches large populations in urban environments. This is probably due to its ability to resist starvation and desiccation. This study aimed to evaluate the effects of absence of water and food on survival and weight change among adult P. americana individuals and check whether the initial weight of individuals influences on their survival. Four groups having twenty P. americana couples were formed and subject to: I no water or food; II no food; III no water; and IV control group. Insects were isolated according to the groups, which were weighed at the beginning and end of the stress conditions. They remained under these conditions until all individuals in each test group were dead. Stress conditions caused reduction in survival time when compared to the control group. Adults with higher body mass survived longer when deprived only of food, while among those lacking water, weight had no influence on survival. Total weight loss was greater among individuals deprived of water than those deprived only of food.

  8. Survival and weight change among adult individuals of Periplaneta americana (Linnaeus, 1758 (Blattaria, Blattidae subject to various stress conditions

    Directory of Open Access Journals (Sweden)

    Jucelio Peter Duarte

    2015-03-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2015v28n2p103 Periplaneta americana is a species of great importance to public health, since it can act as a vector of many pathogens and it reaches large populations in urban environments. This is probably due to its ability to resist starvation and desiccation. This study aimed to evaluate the effects of absence of water and food on survival and weight change among adult P. americana individuals and check whether the initial weight of individuals influences on their survival. Four groups having twenty P. americana couples were formed and subject to: I no water or food; II no food; III no water; and IV control group. Insects were isolated according to the groups, which were weighed at the beginning and end of the stress conditions. They remained under these conditions until all individuals in each test group were dead. Stress conditions caused reduction in survival time when compared to the control group. Adults with higher body mass survived longer when deprived only of food, while among those lacking water, weight had no influence on survival. Total weight loss was greater among individuals deprived of water than those deprived only of food.

  9. Parametric stress analyses for low-level liquid radwaste system piping of ITER subjected to seismic displacements

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Yoon-Suk [Department of Nuclear Engineering, Kyung Hee University, Yongin (Korea, Republic of); Oh, Chang-Kyun [Materials Engineering Department, KEPCO E& C, Yongin (Korea, Republic of); Kim, Hyun-Su, E-mail: hyunsu@kepco-enc.com [Materials Engineering Department, KEPCO E& C, Yongin (Korea, Republic of)

    2015-10-15

    The ITER project is aimed at demonstrating the feasibility of fusion as one of the possible energy options. A layout optimization is one of the design concerns for maintaining safety and reliability of the piping, because some piping penetrating the buildings is subjected to large seismic displacements. The objective of this study is to determine an optimum layout for the radioactive liquid transfer piping to withstand a given seismic displacements combined with internal pressure and thermal expansion. To do this, a series of finite element analyses were performed for various layouts. In addition, the feasibility for utilizing the double-walled structure was investigated. Analysis result shows that effects of the internal pressure and thermal expansion on the total stress are very small compared to that of the seismic displacements. Also, the stress as well as the deformation of the double-walled piping is larger than that of the single-walled piping although the difference is not big. Based on this result, an optimum configuration, a spiral along with U shape, is suggested.

  10. Drought Stress Results in a Compartment-Specific Restructuring of the Rice Root-Associated Microbiomes

    Directory of Open Access Journals (Sweden)

    Christian Santos-Medellín

    2017-07-01

    Full Text Available Plant roots support complex microbial communities that can influence plant growth, nutrition, and health. While extensive characterizations of the composition and spatial compartmentalization of these communities have been performed in different plant species, there is relatively little known about the impact of abiotic stresses on the root microbiota. Here, we have used rice as a model to explore the responses of root microbiomes to drought stress. Using four distinct genotypes, grown in soils from three different fields, we tracked the drought-induced changes in microbial composition in the rhizosphere (the soil immediately surrounding the root, the endosphere (the root interior, and unplanted soils. Drought significantly altered the overall bacterial and fungal compositions of all three communities, with the endosphere and rhizosphere compartments showing the greatest divergence from well-watered controls. The overall response of the bacterial microbiota to drought stress was taxonomically consistent across soils and cultivars and was primarily driven by an enrichment of multiple Actinobacteria and Chloroflexi, as well as a depletion of several Acidobacteria and Deltaproteobacteria. While there was some overlap in the changes observed in the rhizosphere and endosphere communities, several drought-responsive taxa were compartment specific, a pattern likely arising from preexisting compositional differences, as well as plant-mediated processes affecting individual compartments. These results reveal that drought stress, in addition to its well-characterized effects on plant physiology, also results in restructuring of root microbial communities and suggest the possibility that constituents of the altered plant microbiota might contribute to plant survival under extreme environmental conditions.

  11. Solid-state mAbs and ADCs subjected to heat-stress stability conditions can be covalently modified with buffer and excipient molecules.

    Science.gov (United States)

    Valliere-Douglass, John F; Lewis, Patsy; Salas-Solano, Oscar; Jiang, Shan

    2015-02-01

    We report that a unique type of chemical modification occurs on lyophilized proteins. Freeze-dried mAbs and antibody-drug conjugates (ADCs) can be covalently modified with buffer and excipient molecules on the side chains of Glu, Asp, Thr, and Ser amino acids when subjected to temperature stress. The reaction occurs primarily via condensation of common buffers and excipients such as histidine, tris, trehalose and sucrose, with Glu and Asp carboxylates in the primary sequence of proteins. The reaction was also found to proceed through condensation of carboxylate containing buffers such as citrate, with Thr and Ser hydroxyls in the primary sequence of proteins. Based on the mass of the covalent adducts observed on mAbs and ADCs, it is apparent that the reaction produces water as a product and is thus favored in a low moisture environments such as a lyophilized protein cake. Herein, we present the evidence for the covalent modification of proteins drawn from case studies of in-depth characterization of heat-stressed mAbs and ADCs in the solid state. We also demonstrate how common charge variant assays such as imaged capillary isoelectric focusing and mass spectrometry can be used to monitor this specific class of protein modification. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

  12. Measuring general and specific stress causes and stress responses among beginning secondary school teachers in the Netherlands

    OpenAIRE

    Harmsen, R; Helms-Lorenz, M.; Maulana, R; van Veen, K; van Veldhoven, M.J.P.M.

    2018-01-01

    The main aim of this study was to adjust the Questionnaire on the Experience and Evaluation of Work (QEEW) in order to measure stress causes and stress responses of beginning secondary school teachers in the Netherlands. First, the suitability of the original QEEW stress scales for use in the beginning teachers (BTs) context was investigated using a sample of 356 beginning teachers from 52 different secondary school locations in the Netherlands. Confirmatory Factor Analyses, Principal Compone...

  13. Measuring general and specific stress causes and stress responses among beginning secondary school teachers in the Netherlands.

    OpenAIRE

    Harmsen, Ruth; Helms-Lorenz, Michelle; Maulana, Ridwan; van Veen, Klaas; van Veldhoven, M.J.P.M.

    2018-01-01

    The main aim of this study was to adjust the Questionnaire on the Experience and Evaluation of Work (QEEW) in order to measure stress causes and stress responses of beginning secondary school teachers in the Netherlands. First, the suitability of the original QEEW stress scales for use in the beginning teachers (BTs) context was investigated using a sample of 356 beginning teachers from 52 different secondary school locations in the Netherlands. Confirmatory Factor Analyses, Principal Compone...

  14. Subjective health complaints in older adolescents are related to perceived stress, anxiety and gender - a cross-sectional school study in Northern Sweden.

    Science.gov (United States)

    Wiklund, Maria; Malmgren-Olsson, Eva-Britt; Ohman, Ann; Bergström, Erik; Fjellman-Wiklund, Anncristine

    2012-11-16

    Negative trends in adolescent mental and subjective health are a challenge to public health work in Sweden and worldwide. Self-reported mental and subjective health complaints such as pain, sleeping problems, anxiety, and various stress-related problems seem to have increased over time among older adolescents, especially girls. The aim of this study has therefore been to investigate perceived stress, mental and subjective health complaints among older adolescents in Northern Sweden. Data were derived from a cross-sectional school-based survey with a sample consisting of 16-18 year olds (n = 1027), boys and girls, in the first two years of upper secondary school, from different vocational and academic programmes in three public upper secondary schools in a university town in northern Sweden. Prevalence of perceived stress, subjective health complaints, general self-rated health, anxiety, and depression were measured using a questionnaire, including the Hospital Anxiety and Depression Scale (HADS). A large proportion of both girls and boys reported health complaints and perceived stress. There was a clear gender difference: two to three times as many girls as boys reported subjective health complaints, such as headache, tiredness and sleeping difficulties and musculoskeletal pain, as well as sadness and anxiety. High pressure and demands from school were experienced by 63.6% of girls and 38.5% of boys. Perceived stress in the form of pressure and demands correlated strongly with reported health complaints (r = 0.71) and anxiety (r = 0.71). The results indicate that mental and subjective health complaints are prevalent during adolescence, especially in girls, and furthermore, that perceived stress and demands may be important explanatory factors. Future studies should pay attention to the balance between gender-related demands, perceived control and social support, particularly in the school environment, in order to prevent negative strain and stress

  15. Daily Stress, Hearing-Specific Stress and Coping: Self-Reports from Deaf or Hard of Hearing Children and Children with Auditory Processing Disorder

    Science.gov (United States)

    Eschenbeck, Heike; Gillé, Vera; Heim-Dreger, Uwe; Schock, Alexandra; Schott, Andrea

    2017-01-01

    This study evaluated stressors and coping strategies in 70 children who are deaf or hard of hearing (D/HH) or with auditory processing disorder (APD) attending Grades 5 and 6 of a school for deaf and hard-of-hearing children. Everyday general stressors and more hearing-specific stressors were examined in a hearing-specific modified stress and…

  16. Non-parametric model selection for subject-specific topological organization of resting-state functional connectivity.

    Science.gov (United States)

    Ferrarini, Luca; Veer, Ilya M; van Lew, Baldur; Oei, Nicole Y L; van Buchem, Mark A; Reiber, Johan H C; Rombouts, Serge A R B; Milles, J

    2011-06-01

    In recent years, graph theory has been successfully applied to study functional and anatomical connectivity networks in the human brain. Most of these networks have shown small-world topological characteristics: high efficiency in long distance communication between nodes, combined with highly interconnected local clusters of nodes. Moreover, functional studies performed at high resolutions have presented convincing evidence that resting-state functional connectivity networks exhibits (exponentially truncated) scale-free behavior. Such evidence, however, was mostly presented qualitatively, in terms of linear regressions of the degree distributions on log-log plots. Even when quantitative measures were given, these were usually limited to the r(2) correlation coefficient. However, the r(2) statistic is not an optimal estimator of explained variance, when dealing with (truncated) power-law models. Recent developments in statistics have introduced new non-parametric approaches, based on the Kolmogorov-Smirnov test, for the problem of model selection. In this work, we have built on this idea to statistically tackle the issue of model selection for the degree distribution of functional connectivity at rest. The analysis, performed at voxel level and in a subject-specific fashion, confirmed the superiority of a truncated power-law model, showing high consistency across subjects. Moreover, the most highly connected voxels were found to be consistently part of the default mode network. Our results provide statistically sound support to the evidence previously presented in literature for a truncated power-law model of resting-state functional connectivity. Copyright © 2010 Elsevier Inc. All rights reserved.

  17. Investigating genotype specific response in photosynthetic behavior under drought stress and nitrogen limitation in Brassica rapa.

    Science.gov (United States)

    Pleban, J. R.; Mackay, D. S.; Ewers, B. E.; Weinig, C.; Aston, T.

    2015-12-01

    Challenges in terrestrial ecosystem modeling include characterizing the impact of stress on vegetation and the heterogeneous behavior of different species within the environment. In an effort to address these challenges the impacts of drought and nutrient limitation on the CO2 assimilation of multiple genotypes of Brassica rapa was investigated using the Farquhar Model (FM) of photosynthesis following a Bayesian parameterization and updating scheme. Leaf gas exchange and chlorophyll fluorescence measurements from an unstressed group (well-watered/well-fertilized) and two stressed groups (drought/well-fertilized and well-watered/nutrient limited) were used to estimate FM model parameters. Unstressed individuals were used to initialize Bayesian parameter estimation. Posterior mean estimates yielded a close fit with data as observed assimilation (An) closely matched predicted (Ap) with mean standard error for all individuals ranging from 0.8 to 3.1 μmol CO2 m-2 s-1. Posterior parameter distributions of the unstressed individuals were combined and fit to distributions to establish species level Bayesian priors of FM parameters for testing stress responses. Species level distributions of unstressed group identified mean maximum rates of carboxylation standardized to 25° (Vcmax25) as 101.8 μmol m-2 s-1 (± 29.0) and mean maximum rates of electron transport standardized to 25° (Jmax25) as 319.7 μmol m-2 s-1 (± 64.4). These updated priors were used to test the response of drought and nutrient limitations on assimilation. In the well-watered/nutrient limited group a decrease of 28.0 μmol m-2 s-1 was observed in mean estimate of Vcmax25, a decrease of 27.9 μmol m-2 s-1 in Jmax25 and a decrease in quantum yield from 0.40 mol photon/mol e- in unstressed individuals to 0.14 in the nutrient limited group. In the drought/well-fertilized group a decrease was also observed in Vcmax25 and Jmax25. The genotype specific unstressed and stressed responses were then used to

  18. Context specificity of the ANS stress response during two regrouping experiments in goats

    Directory of Open Access Journals (Sweden)

    Antonia Patt

    2016-08-01

    Full Text Available The aim of the present study was to analyze whether the activity of the autonomic nervous system (ANS differs between two regrouping procedures in goats, which would indicate stimulus specificity of these stressors. Applying two regrouping procedures, we evaluated heart rate and heart rate variability (RMSSD, SDNN, RMSSD/SDNN. The two regrouping procedures were 1 introduction of individual goats into established groups (introduction experiment and 2 temporary separation and subsequent reintegration of individuals from/into their group with two levels of contact during separation (separation experiment. In the introduction experiment, the heart rate of introduced goats while lying decreased continuously from an average 78 beats/minute to 68 beats/minute from before the introduction to the last day of the introduction period. Inversely, RMSSD increased continuously from 41 ms to 62 ms, which, on its own, would indicate an adaptation to the situation. During the separation experiment, heart rate while lying was higher when goats were separated in the acoustic contact treatment (82 beats/minute on average compared with the restricted physical contact treatment (75 beats/minute on average. This difference reflected a higher level of arousal during the acoustic contact treatment. However, heart rate activity did not allow detecting effects of separation or reintegration. Even though it can be assumed that both the separation and introduction of goats are stressful for goats, the ANS reactions observed in the present study differed between the two management procedures indicating that the ANS activation was specific to each situation. In addition, we discuss the ANS results in context with earlier findings of variables of the HPA-axis (fecal cortisol metabolites and behavior (lying and feeding. As correspondence between ANS, HPA, and behavioral reactions was limited both within and across experiments, the results of the present study underline the

  19. Identification of stress responsive genes by studying specific relationships between mRNA and protein abundance.

    Science.gov (United States)

    Morimoto, Shimpei; Yahara, Koji

    2018-03-01

    Protein expression is regulated by the production and degradation of mRNAs and proteins but the specifics of their relationship are controversial. Although technological advances have enabled genome-wide and time-series surveys of mRNA and protein abundance, recent studies have shown paradoxical results, with most statistical analyses being limited to linear correlation, or analysis of variance applied separately to mRNA and protein datasets. Here, using recently analyzed genome-wide time-series data, we have developed a statistical analysis framework for identifying which types of genes or biological gene groups have significant correlation between mRNA and protein abundance after accounting for potential time delays. Our framework stratifies all genes in terms of the extent of time delay, conducts gene clustering in each stratum, and performs a non-parametric statistical test of the correlation between mRNA and protein abundance in a gene cluster. Consequently, we revealed stronger correlations than previously reported between mRNA and protein abundance in two metabolic pathways. Moreover, we identified a pair of stress responsive genes ( ADC17 and KIN1 ) that showed a highly similar time series of mRNA and protein abundance. Furthermore, we confirmed robustness of the analysis framework by applying it to another genome-wide time-series data and identifying a cytoskeleton-related gene cluster (keratin 18, keratin 17, and mitotic spindle positioning) that shows similar correlation. The significant correlation and highly similar changes of mRNA and protein abundance suggests a concerted role of these genes in cellular stress response, which we consider provides an answer to the question of the specific relationships between mRNA and protein in a cell. In addition, our framework for studying the relationship between mRNAs and proteins in a cell will provide a basis for studying specific relationships between mRNA and protein abundance after accounting for potential

  20. Context Specificity of the ANS Stress Response during Two Regrouping Experiments in Goats

    Science.gov (United States)

    Patt, Antonia; Gygax, Lorenz; Wechsler, Beat; Hillmann, Edna; Langbein, Jan; Keil, Nina M.

    2016-01-01

    The aim of this study was to analyze whether the activity of the autonomic nervous system (ANS) differs between two regrouping procedures in goats, which would indicate stimulus specificity of these stressors. Applying two regrouping procedures, we evaluated heart rate and heart rate variability (RMSSD, SDNN, and RMSSD/SDNN). The two regrouping procedures were (1) introduction of individual goats into established groups (“introduction experiment”) and (2) temporary separation and subsequent reintegration of individuals from/into their group with two levels of contact during separation (“separation experiment”). In the “introduction experiment,” the heart rate of introduced goats while lying decreased continuously from an average 78 to 68 beats/min from before the introduction to the last day of the introduction period. Inversely, RMSSD increased continuously from 41 to 62 ms, which, on its own, would indicate an adaptation to the situation. During the “separation experiment,” heart rate while lying was higher when goats were separated in the “acoustic contact treatment” (82 beats/min on average) compared with the “restricted physical contact treatment” (75 beats/min on average). This difference reflected a higher level of arousal during the “acoustic contact treatment.” However, heart rate activity did not allow detecting effects of separation or reintegration. Even though it can be assumed that both the separation and introduction of goats are stressful for goats, the ANS reactions observed in this study differed between the two management procedures indicating that the ANS activation was specific to each situation. In addition, we discuss the ANS results in context with earlier findings of variables of the hypothalamic pituitary adrenal (HPA) axis (fecal cortisol metabolites) and behavior (lying and feeding). As correspondence between ANS, HPA, and behavioral reactions was limited both within and across experiments, the results

  1. Using c-Jun to identify fear extinction learning-specific patterns of neural activity that are affected by single prolonged stress.

    Science.gov (United States)

    Knox, Dayan; Stanfield, Briana R; Staib, Jennifer M; David, Nina P; DePietro, Thomas; Chamness, Marisa; Schneider, Elizabeth K; Keller, Samantha M; Lawless, Caroline

    2018-04-02

    Neural circuits via which stress leads to disruptions in fear extinction is often explored in animal stress models. Using the single prolonged stress (SPS) model of post traumatic stress disorder and the immediate early gene (IEG) c-Fos as a measure of neural activity, we previously identified patterns of neural activity through which SPS disrupts extinction retention. However, none of these stress effects were specific to fear or extinction learning and memory. C-Jun is another IEG that is sometimes regulated in a different manner to c-Fos and could be used to identify emotional learning/memory specific patterns of neural activity that are sensitive to SPS. Animals were either fear conditioned (CS-fear) or presented with CSs only (CS-only) then subjected to extinction training and testing. C-Jun was then assayed within neural substrates critical for extinction memory. Inhibited c-Jun levels in the hippocampus (Hipp) and enhanced functional connectivity between the ventromedial prefrontal cortex (vmPFC) and basolateral amygdala (BLA) during extinction training was disrupted by SPS in the CS-fear group only. As a result, these effects were specific to emotional learning/memory. SPS also disrupted inhibited Hipp c-Jun levels, enhanced BLA c-Jun levels, and altered functional connectivity among the vmPFC, BLA, and Hipp during extinction testing in SPS rats in the CS-fear and CS-only groups. As a result, these effects were not specific to emotional learning/memory. Our findings suggest that SPS disrupts neural activity specific to extinction memory, but may also disrupt the retention of fear extinction by mechanisms that do not involve emotional learning/memory. Copyright © 2017 Elsevier B.V. All rights reserved.

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

    Science.gov (United States)

    Anyan, Frederick; Bizumic, Boris; Hjemdal, Odin

    2018-03-01

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

  3. Tract-specific analysis of white matter pathways in healthy subjects: a pilot study using diffusion tensor MRI

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    Yasmin, Hasina; Abe, Osamu; Nakata, Yasuhiro; Hayashi, Naoto; Masutani, Yoshitaka; Goto, Masami; Ohtomo, Kuni [University of Tokyo, Department of Radiology, Bunkyo-ku, Tokyo (Japan); Aoki, Shigeki [Juntendo University, Department of Radiology, Bunkyo-ku, Tokyo (Japan)

    2009-12-15

    To date, very scant data is available regarding normal diffusion properties of white matter (WM) fibers. The present study aimed to initiate the establishment of a database of normal diffusion tensor metrics of cerebral WM fibers, including the uncinate fasciculus (UF), posterior cingulum (PC), fornix, and corticospinal tract (CST) for healthy adults using tract-specific analysis by diffusion tensor tractography (DTT). We also attempted to clarify whether age and laterality exerted any effects on this study group. DTT of WM fibers were generated for 100 healthy subjects, then mean diffusivity (MD) and fractional anisotropy (FA) of the tracts were measured. Pearson correlation analysis was used to evaluate age relationships. Paired t testing was used to compare hemispheric asymmetry. Interobserver correlation tests were also performed. Our results showed FA values for UF (right, 0.42 {+-} 0.03; left, 0.40{+-}0.03), PC (0.51 {+-} 0.06, 0.52 {+-} 0.06), fornix (0.37 {+-} 0.06, 0.38 {+-} 0.06), CST (0.70 {+-} 0.06, 0.69 {+-} 0.07), and MD values for UF (0.81 {+-} 0.03, 0.82 {+-} 0.04), PC (0.72 {+-} 0.03, 0.72 {+-} 0.04), fornix (1.86 {+-} 0.32, 1.94 {+-} 0.37), and CST (0.72 {+-} 0.03, 0.74 {+-} 0.04). We identified a significant positive correlation between age and MD in the right UF and bilateral fornices, and a negative correlation between age and FA in bilateral fornices. Hemispheric asymmetry was observed in FA of UF (right > left) and MD of CST (left > right). The results constitute a normative dataset for diffusion parameters of four WM tracts that can be used to identify, characterize, and establish the significance of changes in diseases affecting specific tracts. (orig.)

  4. Methodological Aspects of Subjective Life Expectancy: Effects of Culture-Specific Reporting Heterogeneity Among Older Adults in the United States.

    Science.gov (United States)

    Lee, Sunghee; Smith, Jacqui

    2016-05-01

    Subjective life expectancy (SLE) has been suggested as a predictor of mortality and mortality-related behaviors. Although critical for culturally diverse societies, these findings do not consider cross-cultural methodological comparability. Culture-specific reporting heterogeneity is a well-known phenomenon introducing biases, and research on this issue with SLE is not established. Using data from the Health and Retirement Study, we examined reporting heterogeneity in SLE focusing on item nonresponse, focal points, and reports over time for five ethnic-cultural groups: non-Hispanic Whites, non-Hispanic Blacks, non-Hispanic other races, English-interviewed Hispanics, and Spanish-interviewed Hispanics. On item nonresponse, Spanish-interviewed Hispanics said, "I don't know," to SLE significantly more than any other groups. Nearly half of the respondents chose 0, 50, or 100, making them focal points. However, the focal points differed: 50 for Whites, 100 for Blacks, and 0 for Spanish-interviewed Hispanics. The relationship of SLE measured at two time points was higher for Whites than minorities. Moreover, those who said "I don't know" to SLE showed higher subsequent mortality than those who gave an answer. SLE was not a significant mortality predictor for Hispanics. Overall, SLE is not free from culture-specific reporting heterogeneity. This warrants further research about its culture-relevant measurement mechanisms. © The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  5. Age-related mechanism and its relationship with secondary metabolism and abscisic acid in Aristotelia chilensis plants subjected to drought stress.

    Science.gov (United States)

    González-Villagra, Jorge; Rodrigues-Salvador, Acácio; Nunes-Nesi, Adriano; Cohen, Jerry D; Reyes-Díaz, Marjorie M

    2018-03-01

    Drought stress is the most important stress factor for plants, being the main cause of agricultural crop loss in the world. Plants have developed complex mechanisms for preventing water loss and oxidative stress such as synthesis of abscisic acid (ABA) and non-enzymatic antioxidant compounds such as anthocyanins, which might help plants to cope with abiotic stress as antioxidants and for scavenging reactive oxygen species. A. chilensis (Mol.) is a pioneer species, colonizing and growing on stressed and disturbed environments. In this research, an integrated analysis of secondary metabolism in Aristotelia chilensis was done to relate ABA effects on anthocyanins biosynthesis, by comparing between young and fully-expanded leaves under drought stress. Plants were subjected to drought stress for 20 days, and physiological, biochemical, and molecular analyses were performed. The relative growth rate and plant water status were reduced in stressed plants, with young leaves significantly more affected than fully-expanded leaves beginning from the 5th day of drought stress. A. chilensis plants increased their ABA and total anthocyanin content and showed upregulation of gene expression when they were subjected to severe drought (day 20), with these effects being higher in fully-expanded leaves. Multivariate analysis indicated a significant positive correlation between transcript levels for NCED1 (9-cis-epoxycarotenoid dioxygenase) and UFGT (UDP glucose: flavonoid-3-O-glucosyltransferase) with ABA and total anthocyanin, respectively. Thus, this research provides a more comprehensive analysis of the mechanisms that allow plants to cope with drought stress. This is highlighted by the differences between young and fully-expanded leaves, showing different sensibility to stress due to their ability to synthesize anthocyanins. In addition, this ability to synthesize different and high amounts of anthocyanins could be related to higher NCED1 and MYB expression and ABA levels

  6. Assessing the accuracy of subject-specific, muscle-model parameters determined by optimizing to match isometric strength.

    Science.gov (United States)

    DeSmitt, Holly J; Domire, Zachary J

    2016-12-01

    Biomechanical models are sensitive to the choice of model parameters. Therefore, determination of accurate subject specific model parameters is important. One approach to generate these parameters is to optimize the values such that the model output will match experimentally measured strength curves. This approach is attractive as it is inexpensive and should provide an excellent match to experimentally measured strength. However, given the problem of muscle redundancy, it is not clear that this approach generates accurate individual muscle forces. The purpose of this investigation is to evaluate this approach using simulated data to enable a direct comparison. It is hypothesized that the optimization approach will be able to recreate accurate muscle model parameters when information from measurable parameters is given. A model of isometric knee extension was developed to simulate a strength curve across a range of knee angles. In order to realistically recreate experimentally measured strength, random noise was added to the modeled strength. Parameters were solved for using a genetic search algorithm. When noise was added to the measurements the strength curve was reasonably recreated. However, the individual muscle model parameters and force curves were far less accurate. Based upon this examination, it is clear that very different sets of model parameters can recreate similar strength curves. Therefore, experimental variation in strength measurements has a significant influence on the results. Given the difficulty in accurately recreating individual muscle parameters, it may be more appropriate to perform simulations with lumped actuators representing similar muscles.

  7. Content specificity of attentional bias to threat in post-traumatic stress disorder.

    Science.gov (United States)

    Zinchenko, A; Al-Amin, M M; Alam, M M; Mahmud, W; Kabir, N; Reza, H M; Burne, T H J

    2017-08-01

    Attentional bias to affective information and reduced cognitive control may maintain the symptoms of post-traumatic stress disorder (PTSD) and impair cognitive functioning. However, the role of content specificity of affective stimuli (e.g., trauma-related, emotional trauma-unrelated) in the observed attentional bias and cognitive control is less clear, as this has not been tested simultaneously before. Therefore, we examined the content specificity of attentional bias to threat in PTSD. PTSD participants (survivors of a multistory factory collapse, n=30) and matched controls (n=30) performed an Eriksen Flanker task. They identified the direction of a centrally presented target arrow, which was flanked by several task-irrelevant distractor arrows pointed to the same (congruent) or opposite direction (incongruent). Additionally, participants were presented with a picture of a face (neutral, emotional) or building (neutral=normal, emotional=collapsed multistory factory) as a task-irrelevant background image. We found that PTSD participants produced overall larger conflict effects and longer reaction times (RT) to emotional than to neutral stimuli relative to their healthy counterparts. Moreover, PTSD, but not healthy participants showed a stimulus specific dissociation in processing emotional stimuli. Emotional faces elicited longer RTs compared to neutral faces, while emotional buildings elicited faster responses, compared to neutral buildings. PTSD patients show a content-sensitive attentional bias to emotional information and impaired cognitive control. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Metabolite Profiling of Barley Grains Subjected to Water Stress: To Explain the Genotypic Difference in Drought-Induced Impacts on Malting Quality

    Directory of Open Access Journals (Sweden)

    Xiaojian Wu

    2017-09-01

    Full Text Available Grain weight and protein content will be reduced and increased, respectively, when barley is subjected to water stress after anthesis, consequently deteriorating the malt quality. However, such adverse impact of water stress differs greatly among barley genotypes. In this study, two Tibetan wild barley accessions and two cultivated varieties differing in water stress tolerance were used to investigate the genotypic difference in metabolic profiles during grain-filling stage under drought condition. Totally, 71 differently accumulated metabolites were identified, including organic acids, amino acids/amines, and sugars/sugar alcohols. Their relative contents were significantly affected by water stress for all genotypes and differed distinctly between the wild and cultivated barleys. The principal component analysis of metabolites indicated that the Tibetan wild barley XZ147 possessed a unique response to water stress. When subjected to water stress, the wild barley XZ147 showed the most increase of β-amylase activity among the four genotypes, as a result of its higher lysine content, less indole-3-acetic acid (IAA biosynthesis, more stable H2O2 homeostasis, and more up-regulation of BMY1 gene. On the other hand, XZ147 had the most reduction of β-glucan content under water stress than the other genotypes, which could be explained by the faster grain filling process and the less expression of β-glucan synthase gene GSL7. All these results indicated a great potential for XZ147 in barley breeding for improving water stress tolerance.

  9. Strain-specific differences of the effects of stress on memory in Lymnaea.

    Science.gov (United States)

    Hughes, Emily; Shymansky, Tamila; Swinton, Erin; Lukowiak, Kai S; Swinton, Cayley; Sunada, Hiroshi; Protheroe, Amy; Phillips, Iain; Lukowiak, Ken

    2017-03-01

    Stress alters the ability to form, recall and maintain memory according to the Yerkes-Dodson/Hebb (YDH) law. The effects of environmentally relevant stressors, such as low environmental calcium and crowding, on learning and memory have previously been described in a laboratory-reared 'average' strain of Lymnaea stagnalis (i.e. the Dutch strain) as well as two strains of freshly collected L . stagnalis with enhanced memory formation abilities (i.e. 'smart' snails). Here, we use L . stagnalis to study the effects of other environmentally relevant stressors on memory formation in two other strains of freshly collected snails, one 'smart' and one 'average'. The stressors we examined are thermal, resource restriction combined with food odour, predator detection and, for the first time, tissue injury (shell damage). We show that the same stressor has significantly different effects on memory formation depending on whether snails are 'smart' or 'average'. Specifically, our data suggest that a stressor or a combination of stressors act to enhance memory in 'average' snails but obstruct memory formation in 'smart' snails. These results are consistent with the YDH law and our hypothesis that 'smart' snails are more easily stressed than 'average' snails. © 2017. Published by The Company of Biologists Ltd.

  10. Assessing the specificity of posttraumatic stress disorder's dysphoric items within the dysphoria model.

    Science.gov (United States)

    Armour, Cherie; Shevlin, Mark

    2013-10-01

    The factor structure of posttraumatic stress disorder (PTSD) currently used by the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), has received limited support. A four-factor dysphoria model is widely supported. However, the dysphoria factor of this model has been hailed as a nonspecific factor of PTSD. The present study investigated the specificity of the dysphoria factor within the dysphoria model by conducting a confirmatory factor analysis while statistically controlling for the variance attributable to depression. The sample consisted of 429 individuals who met the diagnostic criteria for PTSD in the National Comorbidity Survey. The results concluded that there was no significant attenuation in any of the PTSD items. This finding is pertinent given several proposals for the removal of dysphoric items from the diagnostic criteria set of PTSD in the upcoming DSM-5.

  11. ω-3 and folic acid act against depressive-like behavior and oxidative damage in the brain of rats subjected to early- or late-life stress.

    Science.gov (United States)

    Réus, Gislaine Z; Maciel, Amanda L; Abelaira, Helena M; de Moura, Airam B; de Souza, Thays G; Dos Santos, Thais R; Darabas, Ana Caroline; Parzianello, Murilo; Matos, Danyela; Abatti, Mariane; Vieira, Ana Carolina; Fucillini, Vanessa; Michels, Monique; Dal-Pizzol, Felipe; Quevedo, João

    2018-03-30

    To investigate the antidepressant and antioxidant effects of omega-3, folic acid and n-acetylcysteine (NAC) in rats which were subjected to early or late life stress. Early stress was induced through maternal deprivation (MD), while late life stress was induced using the chronic mild stress (CMS) protocol. Young rats which were subjected to MD and the adult rats which were subjected to CMS were treated with omega-3 fatty acids (0.72 g/kg), NAC (20 mg/kg) or folic acid (50 mg/kg) once/day, for a period of 20 days. Then, the animals' immobility times were evaluated using the forced swimming test. Oxidative stress parameters were evaluated in the brain. Depressive-like behavior induced by CMS was prevented by NAC and folic acid, and depressive-like behavior induced by MD was prevented by NAC, folic acid and omega-3. NAC, folic acid and omega-3 were able to exert antioxidant effects in the brain of rats subjected to CMS or MD. These preventive treatments decreased the levels of protein carbonylation and lipid peroxidation, and also decreased the concentrations of nitrite/nitrate and reduced the activity of myeloperoxidase activity in the rat brain which was induced by CMS or MD. NAC, folic acid and omega-3 increased superoxide dismutase and catalase activities in the rat brain subjected to early or late life stress. NAC, omega-3 and folic acid may present interesting lines of treatment based on their antioxidant properties, which cause an inhibition of behavioral and brain changes that occur from stressful life events. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. Subject-specific increases in serum S-100B distinguish sports-related concussion from sports-related exertion.

    Science.gov (United States)

    Kiechle, Karin; Bazarian, Jeffrey J; Merchant-Borna, Kian; Stoecklein, Veit; Rozen, Eric; Blyth, Brian; Huang, Jason H; Dayawansa, Samantha; Kanz, Karl; Biberthaler, Peter

    2014-01-01

    The on-field diagnosis of sports-related concussion (SRC) is complicated by the lack of an accurate and objective marker of brain injury. To compare subject-specific changes in the astroglial protein, S100B, before and after SRC among collegiate and semi-professional contact sport athletes, and compare these changes to differences in S100B before and after non-contact exertion. Longitudinal cohort study. From 2009-2011, we performed a prospective study of athletes from Munich, Germany, and Rochester, New York, USA. Serum S100B was measured in all SRC athletes at pre-season baseline, within 3 hours of injury, and at days 2, 3 and 7 post-SRC. Among a subset of athletes, S100B was measured after non-contact exertion but before injury. All samples were collected identically and analyzed using an automated electrochemiluminescent assay to quantify serum S100B levels. Forty-six athletes (30 Munich, 16 Rochester) underwent baseline testing. Thirty underwent additional post-exertion S100B testing. Twenty-two athletes (16 Rochester, 6 Munich) sustained a SRC, and 17 had S100B testing within 3 hours post-injury. The mean 3-hour post-SRC S100B was significantly higher than pre-season baseline (0.099±0.008 µg/L vs. 0.058±0.006 µg/L, p = 0.0002). Mean post-exertion S100B was not significantly different than the preseason baseline. S100B levels at post-injury days 2, 3 and 7 were significantly lower than the 3-hour level, and not different than baseline. Both the absolute change and proportional increase in S100B 3-hour post-injury were accurate discriminators of SRC from non-contact exertion without SRC (AUC 0.772 and 0.904, respectively). A 3-hour post-concussion S100B >0.122 µg/L and a proportional S100B increase of >45.9% over baseline were both 96.7% specific for SRC. Relative and absolute increases in serum S100B can accurately distinguish SRC from sports-related exertion, and may be a useful adjunct to the diagnosis of SRC.

  13. Subject-specific increases in serum S-100B distinguish sports-related concussion from sports-related exertion.

    Directory of Open Access Journals (Sweden)

    Karin Kiechle

    Full Text Available The on-field diagnosis of sports-related concussion (SRC is complicated by the lack of an accurate and objective marker of brain injury.To compare subject-specific changes in the astroglial protein, S100B, before and after SRC among collegiate and semi-professional contact sport athletes, and compare these changes to differences in S100B before and after non-contact exertion.Longitudinal cohort study.From 2009-2011, we performed a prospective study of athletes from Munich, Germany, and Rochester, New York, USA. Serum S100B was measured in all SRC athletes at pre-season baseline, within 3 hours of injury, and at days 2, 3 and 7 post-SRC. Among a subset of athletes, S100B was measured after non-contact exertion but before injury. All samples were collected identically and analyzed using an automated electrochemiluminescent assay to quantify serum S100B levels.Forty-six athletes (30 Munich, 16 Rochester underwent baseline testing. Thirty underwent additional post-exertion S100B testing. Twenty-two athletes (16 Rochester, 6 Munich sustained a SRC, and 17 had S100B testing within 3 hours post-injury. The mean 3-hour post-SRC S100B was significantly higher than pre-season baseline (0.099±0.008 µg/L vs. 0.058±0.006 µg/L, p = 0.0002. Mean post-exertion S100B was not significantly different than the preseason baseline. S100B levels at post-injury days 2, 3 and 7 were significantly lower than the 3-hour level, and not different than baseline. Both the absolute change and proportional increase in S100B 3-hour post-injury were accurate discriminators of SRC from non-contact exertion without SRC (AUC 0.772 and 0.904, respectively. A 3-hour post-concussion S100B >0.122 µg/L and a proportional S100B increase of >45.9% over baseline were both 96.7% specific for SRC.Relative and absolute increases in serum S100B can accurately distinguish SRC from sports-related exertion, and may be a useful adjunct to the diagnosis of SRC.

  14. "Like walking into an empty room": effects of eurythmy therapy on stress perception in comparison with a sports intervention from the subjects' perspective-a qualitative study.

    Science.gov (United States)

    Berger, B; Bertram, M; Kanitz, J; Pretzer, K; Seifert, G

    2015-01-01

    Background. Stress and health-related quality of life are important constructs used in treatment evaluation today. This study is based on a randomised controlled trial examining the stress-reducing effect of eurythmy therapy in comparison with step aerobics in 106 healthy but stressed subjects. The aim of the analysis was to characterise changes in the subjective perceptions of the participants. Methods. Interviews were conducted with 76 healthy adults, 36 (f = 31/m = 5) from the eurythmy group and 40 (f = 28/m = 12) from the step aerobics group both analysed by content analysis and phenomenologically. Results. The following categories were identified for the eurythmy therapy group: enabling a productive therapeutic response, emergence of a new perceptual space, reevaluation of the accustomed perception, and emergence of new options for action. Step aerobics places increased physical and intellectual demands. These are perceived differently as pleasant and relaxing, insufficiently challenging and/or boring, and too challenging and thus experienced as stress-enhancing. Conclusion. The qualitative results provided revealing insights into the profound effects of and subjective assignments of meaning to external and internal stress factors. Processes of mental reinterpretation leading to stress reduction can be stimulated by physical procedures such as eurythmy therapy.

  15. Subject-specific bone attenuation correction for brain PET/MR: can ZTE-MRI substitute CT scan accurately?

    Science.gov (United States)

    Khalifé, Maya; Fernandez, Brice; Jaubert, Olivier; Soussan, Michael; Brulon, Vincent; Buvat, Irène; Comtat, Claude

    2017-10-01

    In brain PET/MR applications, accurate attenuation maps are required for accurate PET image quantification. An implemented attenuation correction (AC) method for brain imaging is the single-atlas approach that estimates an AC map from an averaged CT template. As an alternative, we propose to use a zero echo time (ZTE) pulse sequence to segment bone, air and soft tissue. A linear relationship between histogram normalized ZTE intensity and measured CT density in Hounsfield units (HU ) in bone has been established thanks to a CT-MR database of 16 patients. Continuous AC maps were computed based on the segmented ZTE by setting a fixed linear attenuation coefficient (LAC) to air and soft tissue and by using the linear relationship to generate continuous μ values for the bone. Additionally, for the purpose of comparison, four other AC maps were generated: a ZTE derived AC map with a fixed LAC for the bone, an AC map based on the single-atlas approach as provided by the PET/MR manufacturer, a soft-tissue only AC map and, finally, the CT derived attenuation map used as the gold standard (CTAC). All these AC maps were used with different levels of smoothing for PET image reconstruction with and without time-of-flight (TOF). The subject-specific AC map generated by combining ZTE-based segmentation and linear scaling of the normalized ZTE signal into HU was found to be a good substitute for the measured CTAC map in brain PET/MR when used with a Gaussian smoothing kernel of 4~mm corresponding to the PET scanner intrinsic resolution. As expected TOF reduces AC error regardless of the AC method. The continuous ZTE-AC performed better than the other alternative MR derived AC methods, reducing the quantification error between the MRAC corrected PET image and the reference CTAC corrected PET image.

  16. Stress fractures of the foot and ankle, part 2: site-specific etiology, imaging, and treatment, and differential diagnosis.

    Science.gov (United States)

    Mandell, Jacob C; Khurana, Bharti; Smith, Stacy E

    2017-09-01

    Stress fractures of the foot and ankle are a commonly encountered problem among athletes and individuals participating in a wide range of activities. This illustrated review, the second of two parts, discusses site-specific etiological factors, imaging appearances, treatment options, and differential considerations of stress fractures of the foot and ankle. The imaging and clinical management of stress fractures of the foot and ankle are highly dependent on the specific location of the fracture, mechanical forces acting upon the injured site, vascular supply of the injured bone, and the proportion of trabecular to cortical bone at the site of injury. The most common stress fractures of the foot and ankle are low risk and include the posteromedial tibia, the calcaneus, and the second and third metatarsals. The distal fibula is a less common location, and stress fractures of the cuboid and cuneiforms are very rare, but are also considered low risk. In contrast, high-risk stress fractures are more prone to delayed union or nonunion and include the anterior tibial cortex, medial malleolus, navicular, base of the second metatarsal, proximal fifth metatarsal, hallux sesamoids, and the talus. Of these high-risk types, stress fractures of the anterior tibial cortex, the navicular, and the proximal tibial cortex may be predisposed to poor healing because of the watershed blood supply in these locations. The radiographic differential diagnosis of stress fracture includes osteoid osteoma, malignancy, and chronic osteomyelitis.

  17. Stress

    Science.gov (United States)

    ... can be life-saving. But chronic stress can cause both physical and mental harm. There are at least three different types of stress: Routine stress related to the pressures of work, family, and other daily responsibilities Stress brought about ...

  18. ST-segment deviation during 24-hour ambulatory electrocardiographic monitoring and exercise stress test in healthy male subjects 51 to 75 years of age: the Copenhagen City Heart Study

    DEFF Research Database (Denmark)

    Vaage-Nilsen, M; Rasmussen, Verner; Sørum, C

    1999-01-01

    or descending ST-segment depression of >/=0.15 mV during Holter monitoring or at the exercise test, respectively. Furthermore, the specificity was 0.95 when a horizontal or downsloping ST-segment depression of 0.1 mV was displayed in both the Holter and exercise electrocardiographic recording system......BACKGROUND: Although ST-segment deviation has been evaluated and used during many years both on continuous electrocardiographic Holter monitoring and during exercise stress testing, considerable controversy still remains concerning the prevalence and diagnostic significance of fortuitously...... discovered ST-segment deviation in asymptomatic healthy persons. METHODS AND RESULTS: The occurrence of ST-segment deviation was studied in a population of 63 clinically healthy male subjects 51 to 75 years of age, with the use of 24-hour Holter monitoring and exercise stress testing. The subjects were...

  19. Identification of stress responsive genes by studying specific relationships between mRNA and protein abundance

    Directory of Open Access Journals (Sweden)

    Shimpei Morimoto

    2018-03-01

    Full Text Available Protein expression is regulated by the production and degradation of mRNAs and proteins but the specifics of their relationship are controversial. Although technological advances have enabled genome-wide and time-series surveys of mRNA and protein abundance, recent studies have shown paradoxical results, with most statistical analyses being limited to linear correlation, or analysis of variance applied separately to mRNA and protein datasets. Here, using recently analyzed genome-wide time-series data, we have developed a statistical analysis framework for identifying which types of genes or biological gene groups have significant correlation between mRNA and protein abundance after accounting for potential time delays. Our framework stratifies all genes in terms of the extent of time delay, conducts gene clustering in each stratum, and performs a non-parametric statistical test of the correlation between mRNA and protein abundance in a gene cluster. Consequently, we revealed stronger correlations than previously reported between mRNA and protein abundance in two metabolic pathways. Moreover, we identified a pair of stress responsive genes (ADC17 and KIN1 that showed a highly similar time series of mRNA and protein abundance. Furthermore, we confirmed robustness of the analysis framework by applying it to another genome-wide time-series data and identifying a cytoskeleton-related gene cluster (keratin 18, keratin 17, and mitotic spindle positioning that shows similar correlation. The significant correlation and highly similar changes of mRNA and protein abundance suggests a concerted role of these genes in cellular stress response, which we consider provides an answer to the question of the specific relationships between mRNA and protein in a cell. In addition, our framework for studying the relationship between mRNAs and proteins in a cell will provide a basis for studying specific relationships between mRNA and protein abundance after

  20. Pair-housing of male and female rats during chronic stress exposure results in gender-specific behavioral responses

    NARCIS (Netherlands)

    Westenbroek, C.; Snijders, T.A.B.; Den Boer, J.A.; Gerrits, Marjolein; Fokkema, D.S.; ter Horst, G.J

    Social support has a positive influence on the course of a depression and social housing of rats could provide an animal model for studying the neurobiological mechanisms of social support. Male and female rats were subjected to chronic footshock stress for 3 weeks and pair-housing of rats was used

  1. Comparative Evaluation of Common Savannahgrass on a Range of Soils Subjected to Different Stresses I: Productivity and Quality

    Directory of Open Access Journals (Sweden)

    Raymond Springer

    2014-04-01

    Full Text Available Turfgrass growth, performance and quality are affected by abiotic stress factors and are of primary concern for persons managing turfgrass areas under seasonal tropical climates. Under these conditions, common Savannahgrass (SG may have a performance advantage over imported hybrid turfgrasses. A greenhouse study was conducted to comparatively evaluate the performance of tropical turfgrasses exposed to water and compaction related stresses across a range of soils, with or without the addition of a surface sand layer. Turfgrass productivity and quality was monitored over a four-month growth period. Clipping yield (CY was lower at the higher compaction effort for all turfgrasses, but across all stresses, drought (D and waterlogging (WL resulted in lower CY. Values were significantly lower under D. SG had the highest clipping yield across all soils. The chlorophyll index (CI was lower for all turfgrasses under water-induced stress compared to compaction stresses. SG had a significantly higher CI across all stress treatments. Correlation analysis showed a positive (r² = 0.420 and significant (p < 0.05 relationship between CY and CI. Similar to CI, stress type influenced turfgrass visual quality (VQ, with D stress, resulting in the lowest VQ rating among turfgrasses. Bermudagrass (BG had the lowest VQ across all stress treatments, whilst, comparatively, Zoysiagrass (ZG had significantly higher VQ under high compaction (HC, low compaction (LC and WL stress. Overall, SG showed a higher level of tolerance to applied stresses and warrants greater attention as a potential turfgrass under tropical conditions.

  2. Estrogen-dependent effects on behavior, lipid-profile, and glycemic index of ovariectomized rats subjected to chronic restraint stress.

    Science.gov (United States)

    da Silva, Caroline Calice; Lazzaretti, Camilla; Fontanive, Tiago; Dartora, Daniela Ravizzoni; Bauereis, Brian; Gamaro, Giovana Duzzo

    2014-03-01

    Stress has been shown to negatively affect the immune system, alter the body's metabolism, and play a strong role in the development of mood disorders. These effects are mainly driven through the release of hormones from the hypothalamic-pituitary-adrenal axis (HPA). Additionally, women are more likely to be affected by stress due to the estrogen fluctuation associated with their menstrual cycle. This study aims to evaluate the effect of chronic restraint stress, applied for 30 days, and estrogen replacement on behavior, glucose level, and the lipid profile of ovariectomized rats. Our results suggest that stress increases sweet food consumption in OVX females treated with estradiol (E2), but reduces consumption in animals not treated. Furthermore, stress increases locomotor activity and anxiety as assessed by the Open Field test and in the Elevated Plus Maze. Similarly, our results suggest that E2 increases anxiety in female rats under the same behavioral tests. In addition, stress reduces glucose and TC levels. Moreover, stress increase TG levels in the presence of E2 and decrease in its absence, as well as the estradiol increase TG levels in stressed groups and reduced in non-stressed groups. Our data suggest an important interaction between stress and estrogen, showing that hormonal status can induce changes in the animal's response to stress. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. REGULAR AND SPECIFIC FEATURES OF STRESSED AND DEFORMED STATE OF COMPOSITE MATERIAL WITH PIERCED OPENING

    Directory of Open Access Journals (Sweden)

    Yu. V. Vasilevich

    2007-01-01

    Full Text Available Mathematical model describing a dependence between deformations and stresses in the zone of prepreg piercing zone is given in the paper. Boundary conditions in the piercing zone in number of four functional dependences for prepregs can express either the given stresses or displacements, or describe boundary form, or express relations between stresses and displacements etc.

  4. Exposure of Arabidopsis thaliana to excess Zn reveals a Zn-specific oxidative stress signature.

    NARCIS (Netherlands)

    Remans, T.; Opdenakker, G.; Guisez, Y.; Carleer, R.; Schat, H.; Vangronsveld, J.; Cuypers, A.

    2012-01-01

    Zinc (Zn) is an essential micronutrient for plants, but accumulation of excess Zn causes oxidative stress, even though the element is not redox-active. An oxidative stress signature, consisting of multiple oxidative stress related parameters, is indicative of disturbance of redox homeostasis and

  5. Gifted Students' Self-Perceptions of Ability in Specific Subject Domains: Factor Structure and Relationship with Above-Level Test Scores

    Science.gov (United States)

    Swiatek, Mary Ann

    2005-01-01

    Current self-concept theories suggest a multi-dimensional construct, with domain-specific self-concepts hierarchically related to global self-concept. The academic domain may be comprised of subject-specific domains that are related to performance in corresponding areas. Here, gifted students' responses to questions about how they compare with…

  6. Plants as Biofactories: Postharvest Stress-Induced Accumulation of Phenolic Compounds and Glucosinolates in Broccoli Subjected to Wounding Stress and Exogenous Phytohormones

    Science.gov (United States)

    Villarreal-García, Daniel; Nair, Vimal; Cisneros-Zevallos, Luis; Jacobo-Velázquez, Daniel A.

    2016-01-01

    Broccoli contains high levels of bioactive molecules and is considered a functional food. In this study, postharvest treatments to enhance the concentration of glucosinolates and phenolic compounds were evaluated. Broccoli whole heads were wounded to obtain florets and wounded florets (florets cut into four even pieces) and stored for 24 h at 20 °C with or without exogenous ethylene (ET, 1000 ppm) or methyl jasmonate (MeJA, 250 ppm). Whole heads were used as a control for wounding treatments. Regarding glucosinolate accumulation, ET selectively induced the 4-hydroxylation of glucobrassicin in whole heads, resulting in ∼223% higher 4-hydroxyglucobrassicin than time 0 h samples. Additionally, glucoraphanin was increased by ∼53% in whole heads treated with ET, while neoglucobrassicin was greatly accumulated in wounded florets treated with ET or MeJA, showing increases of ∼193 and ∼286%, respectively. On the other hand, although only whole heads stored without phytohormones showed higher concentrations of phenolic compounds, which was reflected in ∼33, ∼30, and ∼46% higher levels of 1,2,2-trisinapoylgentiobose, 1,2-diferulolylgentiobiose, and 1,2-disinapoyl-2-ferulolylgentiobiose, respectively; broccoli florets stored under air control conditions showed enhanced concentrations of 3-O-caffeoylquinic acid, 1,2-disinapoylgentiobiose, and 1,2-disinapoyl-2-ferulolylgentiobiose (∼22, ∼185, and ∼65% more, respectively). Furthermore, exogenous ET and MeJA impeded individual phenolics accumulation. Results allowed the elucidation of simple and effective postharvest treatment to enhance the content of individual glucosinolates and phenolic compounds in broccoli. The stressed-broccoli tissue could be subjected to downstream processing in order to extract and purify bioactive molecules with applications in the dietary supplements, agrochemical and cosmetics markets. PMID:26904036

  7. Plants as biofactories: Postharvest Stress-Induced Accumulation of Phenolic Compounds and Glucosinolates in Broccoli Subjected to Wounding Stress and Exogenous Phytohormones

    Directory of Open Access Journals (Sweden)

    Daniel eVillarreal-García

    2016-02-01

    Full Text Available Broccoli contains high levels of bioactive molecules and is considered a functional food. In this study, postharvest treatments to enhance the concentration of glucosinolates and phenolic compounds were evaluated. Broccoli whole heads were wounded to obtain florets and wounded florets (florets cut into four even pieces and stored for 24 h at 20 ºC with or without exogenous ethylene (ET, 1000 ppm or methyl jasmonate (MeJA, 250 ppm. Whole heads were used as a control for wounding treatments. Regarding glucosinolate accumulation, ET selectively induced the 4-hydroxylation of glucobrassicin in whole heads, resulting in ~223% higher 4-hydroxyglucobrassicin than time 0 h samples. Additionally, glucoraphanin was increased by ~53% in whole heads treated with ET, while neoglucobrassicin was greatly accumulated in wounded florets treated with ET or MeJA, showing increases of ~193% and ~286%, respectively. On the other hand, although only whole heads stored without phytohormones showed higher concentrations of phenolic compounds, which was reflected in ~33%, ~30%, and 46% higher levels of 1,2,2-trisinapoylgentiobose, 1,2-diferulolylgentiobiose, and 1,2-disinapoyl-2-ferulolylgentiobiose, respectively; broccoli florets stored under air control conditions showed enhanced concentrations of 3-O-caffeoylquinic acid, 1,2-disinapoylgentiobiose, and 1,2-disinapoyl-2-ferulolylgentiobiose (~22%, ~185%, and ~65% more, respectively. However, exogenous ET and MeJA impeded individual phenolics accumulation. Results allowed the elucidation of simple and effective postharvest treatment to enhance the content of individual glucosinolates and phenolic compounds in broccoli. The stressed-broccoli tissue could be subjected to downstream processing in order to extract and purify bioactive molecules with applications in the dietary supplements, agrochemical and cosmetics markets.

  8. Effect of magnesium, probiotic, and vitamin food supplementation in healthy subjects with psychological stress and evaluation of a persistent effect after discontinuing intake.

    Science.gov (United States)

    Allaert, Francois A; Courau, Stephanie; Forestier, Anne

    2016-12-01

    The aim of this paper was to describe the changes in subjects' psychological stress intensity under the effect of dietary supplements of magnesium, probiotics, and vitamins after one month of intake. Observational cohort study of subject complaining of psychological stress defined by a Perceived Stress Scale (PSS 10) score of more than 21. The study covered 242 healthy volunteers, 38.6±13.6-year-old, among whom 79.8% were women. Under the effect of the supplementation of magnesium, probiotics, and vitamins, the psychological stress of the subjects decreased significantly from 34.1±4.5 to 26.2±6.1 (Pstress level was strictly similar one month after the treatment was discontinued and therefore clearly demonstrated that the psychological benefit was maintained over time. Stress and fatigue are significantly reduced by the intake of a food supplement with probiotics, magnesium, vitamins, and minerals and this effect is fully maintained one month after discontinuing the food supplement intake.

  9. Eye movement desensitisation and reprocessing therapy for posttraumatic stress disorder in a child and an adolescent with mild to borderline intellectual disability: A multiple baseline across subjects study

    NARCIS (Netherlands)

    Mevissen, E.H.M.; Didden, H.C.M.; Korzilius, H.P.L.M.; Jongh, A. de

    2017-01-01

    BACKGROUND: This study explored the effectiveness of eye movement desensitisation and reprocessing (EMDR) therapy for post-traumatic stress disorder (PTSD) in persons with mild to borderline intellectual disability (MBID) using a multiple baseline across subjects design. METHODS: One child and one

  10. Eye Movement Desensitisation and Reprocessing Therapy for Posttraumatic Stress Disorder in a Child and an Adolescent with Mild to Borderline Intellectual Disability: A Multiple Baseline across Subjects Study

    Science.gov (United States)

    Mevissen, Liesbeth; Didden, Robert; Korzilius, Hubert; de Jongh, Ad

    2017-01-01

    Background: This study explored the effectiveness of eye movement desensitisation and reprocessing (EMDR) therapy for post-traumatic stress disorder (PTSD) in persons with mild to borderline intellectual disability (MBID) using a multiple baseline across subjects design. Methods: One child and one adolescent with MBID, who met diagnostic criteria…

  11. Eye movement desensitisation and reprocessing therapy for posttraumatic stress disorder in a child and an adolescent with mild to borderline intellectual disability : A multiple baseline across subjects study

    NARCIS (Netherlands)

    Mevissen, L.; Didden, R.; Korzilius, H.; de Jongh, A.

    2017-01-01

    Background: This study explored the effectiveness of eye movement desensitisation and reprocessing (EMDR) therapy for post-traumatic stress disorder (PTSD) in persons with mild to borderline intellectual disability (MBID) using a multiple baseline across subjects design. Methods: One child and one

  12. Context Specificity of Stress-activated Mitogen-activated Protein (MAP) Kinase Signaling: The Story as Told by Caenorhabditis elegans*

    Science.gov (United States)

    Andrusiak, Matthew G.; Jin, Yishi

    2016-01-01

    Stress-associated p38 and JNK mitogen-activated protein (MAP) kinase signaling cascades trigger specific cellular responses and are involved in multiple disease states. At the root of MAP kinase signaling complexity is the differential use of common components on a context-specific basis. The roundworm Caenorhabditis elegans was developed as a system to study genes required for development and nervous system function. The powerful genetics of C. elegans in combination with molecular and cellular dissections has led to a greater understanding of how p38 and JNK signaling affects many biological processes under normal and stress conditions. This review focuses on the studies revealing context specificity of different stress-activated MAPK components in C. elegans. PMID:26907690

  13. Context Specificity of Stress-activated Mitogen-activated Protein (MAP) Kinase Signaling: The Story as Told by Caenorhabditis elegans.

    Science.gov (United States)

    Andrusiak, Matthew G; Jin, Yishi

    2016-04-08

    Stress-associated p38 and JNK mitogen-activated protein (MAP) kinase signaling cascades trigger specific cellular responses and are involved in multiple disease states. At the root of MAP kinase signaling complexity is the differential use of common components on a context-specific basis. The roundwormCaenorhabditis eleganswas developed as a system to study genes required for development and nervous system function. The powerful genetics ofC. elegansin combination with molecular and cellular dissections has led to a greater understanding of how p38 and JNK signaling affects many biological processes under normal and stress conditions. This review focuses on the studies revealing context specificity of different stress-activated MAPK components inC. elegans. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  14. Reperfusion does not induce oxidative stress but sustained endoplasmic reticulum stress in livers of rats subjected to traumatic-hemorrhagic shock.

    Science.gov (United States)

    Duvigneau, Johanna Catharina; Kozlov, Andrey V; Zifko, Clara; Postl, Astrid; Hartl, Romana T; Miller, Ingrid; Gille, Lars; Staniek, Katrin; Moldzio, Rudolf; Gregor, Wolfgang; Haindl, Susanne; Behling, Tricia; Redl, Heinz; Bahrami, Soheyl

    2010-03-01

    Oxidative stress is believed to accompany reperfusion and to mediate dysfunction of the liver after traumatic-hemorrhagic shock (THS). Recently, endoplasmic reticulum (ER) stress has been suggested as an additional factor. This study investigated whether reperfusion after THS leads to increased oxidative and/or ER stress in the liver. In a rat model, including laparotomy, bleeding until decompensation, followed by inadequate or adequate reperfusion phase, three time points were investigated: 40 min, 3 h, and 18 h after shock. The reactive oxygen and nitrogen species and its scavenging capacity (superoxide dismutase 2), the nitrotyrosine formation in proteins, and the lipid peroxidation together with the status of endogenous antioxidants (alpha-tocopherylquinone-alpha-tocopherol ratio) were investigated as markers for oxidative or nitrosylative stress. Mitochondrial function and cytochrome P450 isoform 1A1 activity were analyzed as representatives for hepatocyte function. Activation of the inositol-requiring enzyme 1/X-box binding protein pathway and up-regulation of the 78-kDa glucose-regulated protein were recorded as ER stress markers. Plasma levels of alanine aminotransferase and Bax/Bcl-XL messenger RNA (mRNA) ratio were used as indicators for hepatocyte damage and apoptosis induction. Oxidative or nitrosylative stress markers or representatives of hepatocyte function were unchanged during and short after reperfusion (40 min, 3 h after shock). In contrast, ER stress markers were elevated and paralleled those of hepatocyte damage. Incidence for sustained ER stress and subsequent apoptosis induction were found at 18 h after shock. Thus, THS or reperfusion induces early and persistent ER stress of the liver, independent of oxidative or nitrosylative stress. Although ER stress was not associated with depressed hepatocyte function, it may act as an early trigger of protracted cell death, thereby contributing to delayed organ failure after THS.

  15. Subjective health complaints in older adolescents are related to perceived stress, anxiety and gender – a cross-sectional school study in Northern Sweden

    Directory of Open Access Journals (Sweden)

    Wiklund Maria

    2012-11-01

    Full Text Available Abstract Background Negative trends in adolescent mental and subjective health are a challenge to public health work in Sweden and worldwide. Self-reported mental and subjective health complaints such as pain, sleeping problems, anxiety, and various stress-related problems seem to have increased over time among older adolescents, especially girls. The aim of this study has therefore been to investigate perceived stress, mental and subjective health complaints among older adolescents in Northern Sweden. Methods Data were derived from a cross-sectional school-based survey with a sample consisting of 16–18 year olds (n = 1027, boys and girls, in the first two years of upper secondary school, from different vocational and academic programmes in three public upper secondary schools in a university town in northern Sweden. Prevalence of perceived stress, subjective health complaints, general self-rated health, anxiety, and depression were measured using a questionnaire, including the Hospital Anxiety and Depression Scale (HADS. Results A large proportion of both girls and boys reported health complaints and perceived stress. There was a clear gender difference: two to three times as many girls as boys reported subjective health complaints, such as headache, tiredness and sleeping difficulties and musculoskeletal pain, as well as sadness and anxiety. High pressure and demands from school were experienced by 63.6% of girls and 38.5% of boys. Perceived stress in the form of pressure and demands correlated strongly with reported health complaints (r = 0.71 and anxiety (r = 0.71. Conclusions The results indicate that mental and subjective health complaints are prevalent during adolescence, especially in girls, and furthermore, that perceived stress and demands may be important explanatory factors. Future studies should pay attention to the balance between gender-related demands, perceived control and social support, particularly in the

  16. The Neuron-Specific Protein TMEM59L Mediates Oxidative Stress-Induced Cell Death.

    Science.gov (United States)

    Zheng, Qiuyang; Zheng, Xiaoyuan; Zhang, Lishan; Luo, Hong; Qian, Lingzhi; Fu, Xing; Liu, Yiqian; Gao, Yuehong; Niu, Mengxi; Meng, Jian; Zhang, Muxian; Bu, Guojun; Xu, Huaxi; Zhang, Yun-Wu

    2017-08-01

    TMEM59L is a newly identified brain-specific membrane-anchored protein with unknown functions. Herein we found that both TMEM59L and its homolog, TMEM59, are localized in Golgi and endosomes. However, in contrast to a ubiquitous and relatively stable temporal expression of TMEM59, TMEM59L expression was limited in neurons and increased during development. We also found that both TMEM59L and TMEM59 interacted with ATG5 and ATG16L1, and that overexpression of them triggered cell autophagy. However, overexpression of TMEM59L induced intrinsic caspase-dependent apoptosis more dramatically than TMEM59. In addition, downregulation of TMEM59L prevented neuronal cell death and caspase-3 activation caused by hydrogen peroxide insults and reduced the lipidation of LC3B. Finally, we found that AAV-mediated knockdown of TMEM59L in mice significantly ameliorated caspase-3 activation, increased mouse duration in the open arm during elevated plus maze test, reduced mouse immobility time during forced swim test, and enhanced mouse memory during Y-maze and Morris water maze tests. Together, our study indicates that TMEM59L is a pro-apoptotic neuronal protein involved in animal behaviors such as anxiety, depression, and memory, and that TMEM59L downregulation protects neurons against oxidative stress.

  17. Technetium 99m SESTAMIBI myocardial perfusion imaging: Comparison between treadmill, dipyridamole and trans-oesophageal atrial pacing 'stress' tests in normal subjects

    International Nuclear Information System (INIS)

    Primeau, M.; Taillefer, R.; Lambert, R.; Essiambre, R.; Honos, G.

    1991-01-01

    The purpose of this study was to determine the blood clearance, myocardial uptake and heart/lung and heart/liver ratios of technetium 99m methoxyisobutylisonitrile ( 99m Tc-SESTAMIBI) following 3 different types of cardiac stimulation in normal subjects: Treadmill stress (STRESS), intravenous administration of dipyridamole (DIP) and trans-oesophageal atrial pacing (TAP). Ten normal volunteers were submitted to 3 injections of 99m Tc-SESTAMIBI (10 mCi/70 kg, separated by an interval of 7 days) following STRESS (standard Bruce protocol), DIP (0.142 mg/kg.min during 4 min) and TAP procedures. Blood samples were collected from 1 to 60 min after each 99m Tc-SESTAMIBI injection. Planar imaging was performed at 5, 30 and 60 min. Blood retention (percentage of injected dose at 1 min) was 56%±4%, 24%±4% and 38%±6% for STRESS, DIP and TAP, respectively (P 99m Tc-SESTAMIBI. (orig.)

  18. Gambling cognition and subjective well-being as mediators between perceived stress and problem gambling: a cross-cultural study on White and Chinese problem gamblers.

    Science.gov (United States)

    Tang, Catherine So-Kum; Oei, Tian Po

    2011-09-01

    This study aimed to delineate various pathways whereby cognitive and emotional vulnerabilities triggered by stress would lead to disruptive gambling. A multiple mediation framework was proposed to specify that gambling cognition and subjective well-being would mediate the influence of perceived stress on problem gambling. The cross-cultural validity of the proposed framework was examined with 132 White gamblers in Australia and 154 Chinese gamblers in China. They completed psychological scales on perceived stress, gambling expectancy bias, gambling refusal efficacy, negative affect, life satisfaction, and problem gambling. Compared to Chinese gamblers, White gamblers reported higher levels of perceived stress, gambling expectancy bias, and problem gambling as well as more pervasive negative affect and lower levels of life satisfaction. Results showed that the proposed multiple mediation framework fit the data better than two alternative plausible models. Life satisfaction and gambling refusal efficacy were two consistent mediators across White and Chinese gamblers. (c) 2011 APA, all rights reserved.

  19. On the Determination of Concrete Armour Unit Stress including Specific Results related to Dolosse

    OpenAIRE

    Burcharth, H. F.; Howell, G.L.; Liu, Z.

    1991-01-01

    Failures of rubble mound breakwaters armoured with complex types of unreinforced concrete armour units are often due to breakage. This happens when the stresses exceed the material strength. Sufficient parametric studies of the stresses are not yet available to produce design diagrams for structural integrity. The paper presents a general discussion of the problems related to stress etermination and describes the results and the analyses of model tests with 200 kg and 200 g load-cell instrume...

  20. Lost in translation? The potential psychobiotic Lactobacillus rhamnosus (JB-1) fails to modulate stress or cognitive performance in healthy male subjects.

    Science.gov (United States)

    Kelly, John R; Allen, Andrew P; Temko, Andriy; Hutch, William; Kennedy, Paul J; Farid, Niloufar; Murphy, Eileen; Boylan, Geraldine; Bienenstock, John; Cryan, John F; Clarke, Gerard; Dinan, Timothy G

    2017-03-01

    Preclinical studies have identified certain probiotics as psychobiotics - live microorganisms with a potential mental health benefit. Lactobacillus rhamnosus (JB-1) has been shown to reduce stress-related behaviour, corticosterone release and alter central expression of GABA receptors in an anxious mouse strain. However, it is unclear if this single putative psychobiotic strain has psychotropic activity in humans. Consequently, we aimed to examine if these promising preclinical findings could be translated to healthy human volunteers. To determine the impact of L. rhamnosus on stress-related behaviours, physiology, inflammatory response, cognitive performance and brain activity patterns in healthy male participants. An 8week, randomized, placebo-controlled, cross-over design was employed. Twenty-nine healthy male volunteers participated. Participants completed self-report stress measures, cognitive assessments and resting electroencephalography (EEG). Plasma IL10, IL1β, IL6, IL8 and TNFα levels and whole blood Toll-like 4 (TLR-4) agonist-induced cytokine release were determined by multiplex ELISA. Salivary cortisol was determined by ELISA and subjective stress measures were assessed before, during and after a socially evaluated cold pressor test (SECPT). There was no overall effect of probiotic treatment on measures of mood, anxiety, stress or sleep quality and no significant effect of probiotic over placebo on subjective stress measures, or the HPA response to the SECPT. Visuospatial memory performance, attention switching, rapid visual information processing, emotion recognition and associated EEG measures did not show improvement over placebo. No significant anti-inflammatory effects were seen as assessed by basal and stimulated cytokine levels. L. rhamnosus was not superior to placebo in modifying stress-related measures, HPA response, inflammation or cognitive performance in healthy male participants. These findings highlight the challenges associated with

  1. Myocardial uptake and clearance of thallium-201 in normal subjects: comparison of dipyridamole-induced hyperemia with exercise stress

    International Nuclear Information System (INIS)

    Ruddy, T.D.; Gill, J.B.; Finkelstein, D.M.; Strauss, H.W.; McKusick, K.A.; Okada, R.D.; Boucher, C.A.

    1987-01-01

    Thallium-201 uptake and clearance after dipyridamole infusion may differ from that after exercise stress because the hemodynamic effects of these two interventions are different. In this study of normal volunteers, thallium kinetics after dipyridamole (n = 13) were determined from three serial image sets (early, intermediate and delayed) and from serial blood samples and compared with thallium kinetics after exercise (n = 15). Absolute myocardial thallium uptake was greater after dipyridamole compared with exercise (p less than 0.0001), although the relative myocardial distribution was similar. The myocardial clearance (%/h) of thallium was slower after dipyridamole than it was after exercise. Comparing dipyridamole and exercise, the differences in clearance were large from the early to the intermediate image (anterior, -11 +/- 17 versus 24 +/- 5, p = 0.0005; 50 degrees left anterior oblique, -7 +/- 11 versus 15 +/- 8, p = 0.004; 70 degrees left anterior oblique, 3 +/- 9 versus 21 +/- 6, p = 0.001). In contrast, the differences in clearance were small from the intermediate to the delayed image (anterior, 15 +/- 4 versus 20 +/- 2, p = 0.025; 50 degrees left anterior oblique, 15 +/- 4 versus 19 +/- 3, p = 0.13; 70 degrees left anterior oblique, 15 +/- 3 versus 18 +/- 2, p = 0.047). Thallium uptake and clearance in the liver, splanchnic region and spleen were greater after dipyridamole (p less than 0.001). Blood thallium levels were greater after dipyridamole (p less than 0.05) and cleared more slowly (p = 0.07). Thus, myocardial thallium-201 uptake and clearance after dipyridamole infusion differ from thallium kinetics after exercise. This difference is, in part, related to associated differences in extracardiac and blood kinetics. Diagnostic criteria for the detection of abnormal thallium-201 clearance must be specific for the type of intervention

  2. Subject-Verb Agreement and Verbal Short-Term Memory: A Perspective from Greek Children with Specific Language Impairment

    Science.gov (United States)

    Lalioti, Marina; Stavrakaki, Stavroula; Manouilidou, Christina; Talli, Ioanna

    2016-01-01

    This study investigated the performance of school age Greek-speaking children with SLI on verbal short-term memory (VSTM) and Subject-Verb (S-V) agreement in comparison to chronological age controls and younger typically developing children. VSTM abilities were assessed by means of a non-word repetition task (NRT) and an elicited production task,…

  3. Location-specific responses to thermal stress in larvae of the reef-building coral Montastraea faveolata.

    Directory of Open Access Journals (Sweden)

    Nicholas R Polato

    2010-06-01

    Full Text Available The potential to adapt to a changing climate depends in part upon the standing genetic variation present in wild populations. In corals, the dispersive larval phase is particularly vulnerable to the effects of environmental stress. Larval survival and response to stress during dispersal and settlement will play a key role in the persistence of coral populations.To test the hypothesis that larval transcription profiles reflect location-specific responses to thermal stress, symbiont-free gametes from three to four colonies of the scleractinian coral Montastraea faveolata were collected from Florida and Mexico, fertilized, and raised under mean and elevated (up 1 to 2 degrees C above summer mean temperatures. These locations have been shown to exchange larvae frequently enough to prevent significant differentiation of neutral loci. Differences among 1,310 unigenes were simultaneously characterized using custom cDNA microarrays, allowing investigation of gene expression patterns among larvae generated from wild populations under stress. Results show both conserved and location-specific variation in key processes including apoptosis, cell structuring, adhesion and development, energy and protein metabolism, and response to stress, in embryos of a reef-building coral.These results provide first insights into location-specific variation in gene expression in the face of gene flow, and support the hypothesis that coral host genomes may house adaptive potential needed to deal with changing environmental conditions.

  4. Perceived stress and cause-specific mortality among men and women: results from a prospective cohort study

    DEFF Research Database (Denmark)

    Nielsen, Naja Rod; Kristensen, Tage S; Schnohr, Peter

    2008-01-01

    until 2004, with Sex differences were found in the relations between stress and mortality (p = 0.02). After adjustments, men with high stress versus low stress had higher all-cause mortality (hazard ratio (HR) = 1.32, 95% confidence interval (CI): 1.15, 1.52). This finding......The authors assessed the effect of psychological stress on total and cause-specific mortality among men and women. In 1981-1983, the 12,128 Danish participants in the Copenhagen City Heart Study were asked two questions on stress intensity and frequency and were followed in a nationwide registry...... was most pronounced for deaths due to respiratory diseases (high vs. low stress: HR = 1.79, 95% CI: 1.10, 2.91), external causes (HR = 3.07, 95% CI: 1.65, 5.71), and suicide (HR = 5.91, 95% CI: 2.47, 14.16). High stress was related to a 2.59 (95% CI: 1.20, 5.61) higher risk of ischemic heart disease...

  5. Specific alteration of rhythm in temperature-stressed rats possess features of abdominal pain in IBS patients

    Directory of Open Access Journals (Sweden)

    Yasuo Itomi

    2015-09-01

    Full Text Available It is known that specific alteration of rhythm in temperature (SART stress produces somatic pain. However, it remains to be investigated whether SART stress induces visceral pain. In this study, we investigated the visceral hypersensitivity in the SART stress model by pharmacological tools and heterotopical nociception. Four-week-old Sprague–Dawley rats were exposed to repeated cold stress. Visceral pain was measured by visceromotor response to colorectal distension, and the effects of alosetron and duloxetine on visceral pain were investigated in SART rats. Heterotopical nociception was given by capsaicin injection into the left forepaw to induce diffuse noxious inhibitory controls (DNIC. SART stress induced visceral hypersensitivity that was sustained at minimum for one week. In pharmacological analysis, alosetron and duloxetine improved SART stress-induced visceral hypersensitivity. Heterotopical nociception induced DNIC in normal conditions, but was disrupted in SART rats. On the other hand, RMCP-II mRNA in distal colon was not affected by SART stress. In conclusion, SART rats exhibit several features of visceral pain in IBS, and may be a useful model for investigating the central modification of pain control in IBS.

  6. Adolescent Drinking and Adolescent Stress: A Domain-Specific Relationship in Northern Irish Schoolchildren

    Science.gov (United States)

    McKay, Michael Thomas; Cole, Jon C.

    2013-01-01

    Previous research has suggested an association between heightened levels of stress among adolescents and reduced levels of mental, physical and emotional well-being. This study sought to examine the relationship between 10 domains of adolescent stress and self-reported drinking behaviour. A total of 610 adolescents, aged 12-16 years old, were…

  7. Endothelin receptor-specific control of endoplasmic reticulum stress and apoptosis in the kidney.

    Science.gov (United States)

    De Miguel, Carmen; Hamrick, William C; Hobbs, Janet L; Pollock, David M; Carmines, Pamela K; Pollock, Jennifer S

    2017-02-23

    Endothelin-1 (ET-1) promotes renal damage during cardiovascular disease; yet, the molecular mechanisms involved remain unknown. Endoplasmic reticulum (ER) stress, triggered by unfolded protein accumulation in the ER, contributes to apoptosis and organ injury. These studies aimed to determine whether the ET-1 system promotes renal ER stress development in response to tunicamycin. ET B deficient (ET B def) or transgenic control (TG-con) rats were used in the presence or absence of ET A receptor antagonism. Tunicamycin treatment similarly increased cortical ER stress markers in both rat genotypes; however, only ET B def rats showed a 14-24 fold increase from baseline for medullary GRP78, sXBP-1, and CHOP. Pre-treatment of TG-con rats with the ET A blocker ABT-627 for 1 week prior to tunicamycin injection significantly reduced the ER stress response in cortex and medulla, and also inhibited renal apoptosis. Pre-treatment with ABT-627 failed to decrease renal ER stress and apoptosis in ET B def rats. In conclusion, the ET-1 system is important for the development of tunicamycin-induced renal ER stress and apoptosis. ET A receptor activation induces renal ER stress genes and apoptosis, while functional activation of the ET B receptor has protective effects. These results highlight targeting the ET A receptor as a therapeutic approach against ER stress-induced kidney injury.

  8. Specific features of the determination of residual stresses in materials by diffraction techniques

    Science.gov (United States)

    Gorkunov, E. S.; Zadvorkin, S. M.; Goruleva, L. S.

    2017-12-01

    Residual stresses arising in separate machine parts and structural components during production and use to a large extent govern their lifetime. In this connection, the development and improvement of nondestructive methods for the determination of residual stresses is an important task for nondestructive testing. Standards regulate only the determination of macroscopic stresses, and in practice these stresses are most often determined with the application of the sin2ψ method. This paper, using quenched structural steels as an example, compares the results of residual stress determination by the sin2ψ method with those obtained by the method based on the analysis of the diffraction line profile as dependent on the value of the irradiated volume. It is demonstrated that, as the irradiated volume decreases, the value of residual stresses determined by the sin2ψ method may vary considerably, up to the change of the sign. For a more complete characteristic of residual stresses it is proposed to use, besides the determination of macrostresses by the shift of the diffraction lines, the value of microscopic stresses calculated from the line profile analysis.

  9. Using Experts to Validate an Animal Specific Heat Stress Model for Feedlot Cattle

    Science.gov (United States)

    The extreme effects of heat stress in a feedlot situation can cause losses exceeding 5% of all the cattle on feed in a single feedlot. These losses can be very devastating to a localized area of feedlot producers. Animal stress is a result of the combination of three different components: environm...

  10. Interrelations between orthostatic postural deviations and subjects' age, sex, malocclusion, and specific signs and symptoms of functional pathologies of the temporomandibular system: a preliminary correlation and regression study.

    Science.gov (United States)

    Munhoz, Wagner Cesar; Hsing, Wu Tu

    2014-07-01

    Studies on the relationships between postural deviations and the temporomandibular system (TS) functional health are controversial and inconclusive. This study stems from the hypothesis that such inconclusiveness is due to authors considering functional pathologies of the TS (FPTS) as a whole, without taking into account subjects' specific FPTS signs and symptoms. Based on the author and collaborators' previous studies, the present study analyzed data on body posture from a sample of 50 subjects with (30) and without (20) FPTS. Correlation analyses were applied, taking as independent variables age, sex, Helkimo anamnestic, occlusal, and dysfunction indices, as well as FPTS specific signs and symptoms. Postural assessments of the head, cervical spine, shoulders, lumbar spine, and hips were the dependent variables. Linear regression equations were built that proved to partially predict the presence and magnitude of body posture deviations by drawing on subjects' characteristics and specific FPTS symptoms. Determination coefficients for these equations ranged from 0.082 to 0.199 in the univariate, and from 0.121 to 0.502 in the multivariate regression analyses. Results show that factors intrinsic to the subjects or the TS may potentially interfere in results of studies that analyze relationships between FPTS and body posture. Furthermore, a trend to specificity was found, e.g. the degree of cervical lordosis was found to correlate to age and FPTS degree of severity, suggesting that some TS pathological features, or malocclusion, age or sex, may be more strongly correlated than others with specific posture patterns.

  11. Expedited patient-specific assessment of contact stress exposure in the ankle joint following definitive articular fracture reduction.

    Science.gov (United States)

    Kern, Andrew M; Anderson, Donald D

    2015-09-18

    Acute injury severity, altered joint kinematics, and joint incongruity are three important mechanical factors linked to post-traumatic osteoarthritis (PTOA). Finite element analysis (FEA) was previously used to assess the influence of increased contact stress due to joint incongruity on PTOA development. While promising agreement with PTOA development was seen, the inherent complexities of contact FEA limited the numbers of subjects that could be analyzed. Discrete element analysis (DEA) is a simplified methodology for contact stress computation, which idealizes contact surfaces as a bed of independent linear springs. In this study, DEA was explored as an expedited alternative to FEA contact stress exposure computation. DEA was compared to FEA using results from a previously completed validation study of two cadaveric human ankles, as well as a previous study of post-operative contact stress exposure in 11 patients with tibial plafond fracture. DEA-computed maximum contact stresses were within 19% of those experimentally measured, with 90% of the contact area having computed contact stress values within 1MPa of those measured. In the 11 fractured ankles, maximum contact stress and contact area differences between DEA and FEA were 0.85 ± 0.64 MPa and 22.5 ± 11.5mm(2). As a predictive measure for PTOA development, both DEA and FEA had 100% concordance with presence of OA (KL grade ≥ 2) and >95% concordance with KL grade at 2 years. These results support DEA as a reasonable alternative to FEA for computing contact stress exposures following surgical reduction of a tibial plafond fracture. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Cell and Receptor Type-Specific Alterations in Markers of GABA Neurotransmission in the Prefrontal Cortex of Subjects with Schizophrenia

    OpenAIRE

    Lewis, David A.; Hashimoto, Takanori; Morris, Harvey M.

    2008-01-01

    Impairments in cognitive control, such as those involved in working memory, are associated with dysfunction of the dorsolateral prefrontal cortex (DLPFC) in individuals with schizophrenia. This dysfunction appears to result, at least in part, from abnormalities in GABA-mediated neurotransmission. In this paper, we review recent findings indicating that the altered DLPFC circuitry in subjects with schizophrenia reflects changes in the expression of genes that encode selective presynaptic and p...

  13. [The Load of Injustice: A Longitudinal Analysis of the Impact of Subjectively Perceived Income Injustice on the Risk of Stress-Associated Diseases Based on the German Socio-Economic Panel Study].

    Science.gov (United States)

    Boscher, Claudia; Arnold, Laura; Lange, Andreas; Szagun, Bertram

    2018-03-01

    Income injustice is regarded as a psychosocial strain and associated with an increased risk of stress-related diseases. The physiological stress response is thereby considered as a central link. The aim of the study is to reveal the influence of subjectively perceived income injustice on stress-associated diseases, taking into consideration the load duration. Based on the German Socio-Economic Panel Study, data on 5,657 workers in the survey years 2005-2013 were analyzed. The dependent variable reflect the doctor's diagnosed new cases of diabetes, asthma, cardiopathy, stroke, hypertension and depression in the years 2009-2013 as an index. Key predictor is the injustice perception of one's income. In order to operationalize the duration of the injustice perception, the values of the variable for the years 2005, 2007 and 2009 were accumulated. Using logit models, stratified for gender and volume of employment, factors were identified that affect the probability of stress-related diseases. If income was perceived as unjust for over 5 years, the odds of stress-related diseases were strongly enhanced for women (OR 1.64; 95% CI 1.17-2.30). Women working full-time seemed to be particularly affected (OR 2.43; 95% CI 1.54-3.84). Men working full-time perceiving their income as unjust also showed an increased risk for stress diseases (OR 1.43; CI 1.03-1.98). The more often income was assessed as unjust, the higher was the probability of stress-related diseases. Perceived income injustice seems to be a significant risk factor for stress-related diseases within a dose-response relationship with increasing duration of exposure. Findings of stress research indicate that this represents the 'allostatic load'. Gender-specific differences in stress reaction as well as in the appraisal of the stressors can be associated with gender-specific work and life conditions and therefore provide explanatory approaches for the revealed effects. © Georg Thieme Verlag KG Stuttgart · New York.

  14. Chronic stress and peripheral pain: Evidence for distinct, region-specific changes in visceral and somatosensory pain regulatory pathways.

    Science.gov (United States)

    Zheng, Gen; Hong, Shuangsong; Hayes, John M; Wiley, John W

    2015-11-01

    Chronic stress alters the hypothalamic-pituitary-adrenal (HPA) axis and enhances visceral and somatosensory pain perception. It is unresolved whether chronic stress has distinct effects on visceral and somatosensory pain regulatory pathways. Previous studies reported that stress-induced visceral hyperalgesia is associated with reciprocal alterations of endovanilloid and endocannabinoid pain pathways in DRG neurons innervating the pelvic viscera. In this study, we compared somatosensory and visceral hyperalgesia with respect to differential responses of peripheral pain regulatory pathways in a rat model of chronic, intermittent stress. We found that chronic stress induced reciprocal changes in the endocannabinoid 2-AG (increased) and endocannabinoid degradation enzymes COX-2 and FAAH (decreased), associated with down-regulation of CB1 and up-regulation of TRPV1 receptors in L6-S2 DRG but not L4-L5 DRG neurons. In contrast, sodium channels Nav1.7 and Nav1.8 were up-regulated in L4-L5 but not L6-S2 DRGs in stressed rats, which was reproduced in control DRGs treated with corticosterone in vitro. The reciprocal changes of CB1, TRPV1 and sodium channels were cell-specific and observed in the sub-population of nociceptive neurons. Behavioral assessment showed that visceral hyperalgesia persisted, whereas somatosensory hyperalgesia and enhanced expression of Nav1.7 and Nav1.8 sodium channels in L4-L5 DRGs normalized 3 days after completion of the stress phase. These data indicate that chronic stress induces visceral and somatosensory hyperalgesia that involves differential changes in endovanilloid and endocannabinoid pathways, and sodium channels in DRGs innervating the pelvic viscera and lower extremities. These results suggest that chronic stress-induced visceral and lower extremity somatosensory hyperalgesia can be treated selectively at different levels of the spinal cord. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Numerical analysis of residual stress of Al-Mg-Mn-Sc-Zr alloy subjected to surface strengthening by shot peening

    Directory of Open Access Journals (Sweden)

    Mariusz Stegliński

    2015-03-01

    Full Text Available In this paper, we presented the results of the analysis of the stresses in the Al-Mg5%-Mn1,5%-Sc0,8%-Zr0,4% alloy after shot peening process using solver ANSYSANSYSANSYS LS-Dyna. The computational model illustrates the phenomena occurring as a result of plastic deformation caused by hitting a steel ball on the surface of the analyzed aluminium alloy. We analyzed two input variables: diameter and speed of a ball. The resulting normal stress distribution centred exposes the minimum compressive stress at a position located at a depth point of Belayev 0.125 mm with a value of σ = –345 MPa. Variable parameter shows the correlation of the boundary conditions of minimum stress increase with increasing ball’s diameter and its speed. Selected points of numerical analysis were verified with experimental results.[b]Keywords[/b]: materials science, numerical analysis, metal forming, shot peening, aluminium

  16. Detection of Free Polyamines in Plants Subjected to Abiotic Stresses by High-Performance Liquid Chromatography (HPLC).

    Science.gov (United States)

    Gong, Xiaoqing; Liu, Ji-Hong

    2017-01-01

    High-performance liquid chromatography (HPLC) is a sensitive, rapid, and accurate technique to detect and characterize various metabolites from plants. The metabolites are extracted with different solvents and eluted with appropriate mobile phases in a designed HPLC program. Polyamines are known to accumulate under abiotic stress conditions in various plant species and thought to provide protection against oxidative stress by scavenging reactive oxygen species. Here, we describe a common method to detect the free polyamines in plant tissues both qualitatively and quantitatively.

  17. Cortisol response and desire to binge following psychological stress: comparison between obese subjects with and without binge eating disorder.

    Science.gov (United States)

    Rosenberg, Noa; Bloch, Miki; Ben Avi, Irit; Rouach, Vanessa; Schreiber, Shaul; Stern, Naftali; Greenman, Yona

    2013-07-30

    While stress and negative affect are known to precede "emotional eating", this relationship is not fully understood. The objective of this study was to explore the relationship between induced psychological stress, hypothalamic-pituitary-adrenal (HPA) axis activity, and eating behavior in binge eating disorder (BED). The Trier Social Stress Test (TSST) was applied in obese participants with (n=8) and without BED (n=8), and normal weight controls (n=8). Psychological characteristics, eating-related symptoms, and cortisol secretion were assessed. Baseline stress, anxiety and cortisol measures were similar in all groups. At baseline desire to binge was significantly higher among the BED group. While the TSST induced an increase in cortisol levels, a blunted cortisol response was observed in the BED group. In the BED group, a positive correlation was found between cortisol (area under the curve) levels during the TSST and the change in VAS scores for desire to binge. Post-TSST desire to binge and sweet craving were significantly higher in the BED group and correlated positively with stress, anxiety, and cortisol response in the BED group only. These results suggest chronic down-regulation of the HPA axis in participants with BED, and a relationship between psychological stress, the acute activation of the HPA axis, and food craving. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  18. Age-specific neural strategies to maintain motor performance after an acute social stress bout.

    Science.gov (United States)

    Mehta, Ranjana K; Rhee, Joohyun

    2017-07-01

    Stress due to cognitive demands and fatigue have shown to impair motor performance in older adults; however, the effect of social stress and its influence on prefrontal cortex (PFC) functioning in older adults during upper extremity motor performance tasks is not known. The present study explored the after-effects of an acute social stress bout on neural strategies, measured using PFC and hand/arm muscle activation, and adopted by younger and older adults to maintain handgrip force control. Nine older [74.1 (6.5) years; three men, six women] and ten younger [24.2 (5.0) years, four men, six women] adults performed handgrip force control trials at 30% maximum voluntary contractions before and after the Trier Social Stress Test (TSST). PFC activity was measured using functional near infrared spectroscopy and muscle activity from the flexor and extensor carpi radialis (FCR/ECR) was measured using electromyography. In general, aging was associated with decreased force steadiness and force complexity with a concomitant increase in bilateral PFC activity. While motor performance remained comparable before and after the TSST stress session in both age groups, the associated neural strategies differed between groups. While the stress condition was associated with lower FCR and ECR activity in younger adults despite no change in the PFC activation, stress was associated with increases in FCR activity in older adults. This stress-related compensatory neural strategy of increasing hand/arm muscle activation, potentially via the additional recruitment of the stress-motor neural circuitry, may have played a role in maintaining motor performance in older adults.

  19. ADHD-specific stimulant misuse, mood, anxiety, and stress in college-age women at high risk for or with eating disorders

    Science.gov (United States)

    Gibbs, Elise L.; Kass, Andrea E.; Eichen, Dawn M.; Fitzsimmons-Craft, Ellen E.; Trockel, Mickey; Wilfley, Denise E.; Taylor, C. Barr

    2016-01-01

    Objective To examine the misuse of ADHD-specific stimulants in a college population at high risk for or with clinical or subclinical eating disorders. Participants 448 college-age women ages 18–25 at high risk for or with a clinical or subclinical eating disorder. Methods Participants completed assessments of stimulant misuse and psychopathology from September 2009 - June 2010. Results Greater eating disorder pathology, objective binge eating, purging, eating disorder-related clinical impairment, depressive symptoms, perceived stress, and trait anxiety were associated with an increased likelihood of stimulant misuse. Subjective binge eating, excessive exercise, and dietary restraint were not associated with stimulant misuse. Conclusions ADHD-specific stimulant misuse is associated with eating disorder and comorbid pathology among individuals at high risk for or with clinical or subclinical eating disorders. Screening for stimulant misuse and eating disorder pathology may improve identification of college-age women who may be engaging in maladaptive behaviors and inform prevention efforts. PMID:26822019

  20. Sex-Specific Effects of Unpredictable Variable Prenatal Stress: Implications for Mammalian Developmental Programming During Spaceflight

    Science.gov (United States)

    Talyansky, Y.; Moyer, E. L.; Oijala, E.; Baer, L. A.; Ronca, A. E.

    2016-01-01

    During adaptation to the microgravity environment, adult mammals experience stress mediated by the Hypothalamic-Pituitary-Adrenal axis. In our previous studies of pregnant rats exposed to 2-g hypergravity via centrifugation, we reported decreased corticosterone and increased body mass and leptin in adult male, but not female, offspring. In this study, we utilized Unpredictable Variable Prenatal Stress to simulate the stressors of spaceflight by exposing dams to different stressors. Stress response modulation occurs via both positive and negative feedback in the hypothalamus, anterior pituitary gland, and adrenal cortex resulting in the differential release of corticosterone (CORT), a murine analog to human cortisol.

  1. A PVDF-Based Sensor for Internal Stress Monitoring of a Concrete-Filled Steel Tubular (CFST) Column Subject to Impact Loads.

    Science.gov (United States)

    Du, Guofeng; Li, Zhao; Song, Gangbing

    2018-05-23

    Impact loads can have major adverse effects on the safety of civil engineering structures, such as concrete-filled steel