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Stress Group (stress + group)
Selected AbstractsPsychological Stress and Oxidative Damage in Lymphocytes of Aerobically Fit and Unfit Individuals,JOURNAL OF APPLIED BIOBEHAVIORAL RESEARCH, Issue 1 2008Kelly Z. Knickelbein Habitual aerobic exercise has a beneficial effect on many systems of the body, and psychological stress has a negative influence on several of the same systems. One possible pathway is through those systems that account for the detrimental effects of stress; by buffering these harmful effects, exercise may reduce the consequences of stress. This study examined increased resistance of cells to stress-induced oxidative damage as a result of fitness. Forty healthy participants were assigned to either a stress group or a no-stress control group, and measures of stress and oxidative damage were collected. Variation in fitness level across participants was also measured. Oxidative damage increased as a function of stress, but this was not buffered by fitness level. These results should be interpreted with caution because of the small sample size and the limited variability of cardiorespiratory fitness levels in the sample. [source] Morphological and molecular changes in denture-supporting tissues under persistent mechanical stress in ratsJOURNAL OF ORAL REHABILITATION, Issue 12 2008M. TSURUOKA Summary, The purpose of this study was to determine the effects of mechanical compression on the palatal mucosa using an experimental palatal base. The palatal base was either pressed onto (stress group) or not pressed onto (fit group) rat palatal mucosa. Blood flow was measured and the animals were sacrificed 6,72 h later for analysis. The expression of heat shock protein 70 (HSP70), vascular endothelial growth factor (VEGF) and proliferation cell nuclear antigen (PCNA) was characterized by immunohistochemical staining. For morphometric analysis, connective tissues were divided into bone side and epithelial side tissues. The ratio of PCNA-positive cells (PCNA score) was calculated, and the expressions of mRNA encoding HSP70 and VEGF was evaluated. Whereas blood flow in the stress group showed ischaemia, none was found in the fit group. Proliferation cell nuclear antigen scores on the bone side were higher than on the epithelial side in the stress group (P < 0·05). Heat shock protein 70- and VEGF-positive cells were observed under compression conditions, particularly in the periosteum. In the stress group, the expressions of mRNA encoding HSP70 and VEGF were highest at 12 h (P < 0·05). These results suggest that mechanical compression of the palatal plate induces ischaemia, and that cells in the underlying denture-supporting tissue, which includes the periosteum, synthesize HSP70 and VEGF to maintain homeostasis under these conditions. [source] CFD modeling of heat transfer in turbulent pipe flowsAICHE JOURNAL, Issue 9 2000S. S. Thakre Twelve versions of low Reynolds number k-, and two low Reynolds number Reynolds stress turbulence models for heat transfer were analyzed comparatively. Predictions of the mean axial temperature, the radial and axial turbulent heat fluxes, and the effect of Prandtl number on Nusselt number were compared with the experimental data. The model by Lai and So from the k-, group and Lai and So from the Reynolds stress group had the best overall predictive ability for heat transfer in turbulent pipe flow. The Lai and So model was attributed to its success in the predictions of flow parameters such as mean axial velocity, turbulent kinetic energy, eddy diffusivity, and the overall energy dissipation rate. The k-, models performed relatively better than the Reynolds stress models for predicting the mean axial temperature and the Nusselt number. This qualitative and quantitative study found the need for more sophisticated near-wall experimental measurements and the accuracy of the dissipation (of turbulent energy) and the pressure-scrambling models. [source] Association between psychosocial factors and musculoskeletal symptoms among Iranian nursesAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 10 2010Ramin Mehrdad MD Abstract Background While psychosocial factors have been associated with musculoskeletal symptoms among nurses in some countries, previous studies of Iranian nurses show little association using a demand and control questionnaire. The aim of this study is to assess and evaluate the prevalence of musculoskeletal symptoms and to assess their relationships with psychosocial factors among nurses in Iran. Methods In a cross-sectional study, 347 hospital nurses completed a self-reported questionnaire containing the Standardized Nordic questionnaire for musculoskeletal symptoms and the General Nordic questionnaire for Psychological and Social factors at work (QPS Nordic 34+ Questionnaire). Results Prevalence of low back pain, knee pain, shoulder pain, and neck pain were 73.2%, 68.7%, 48.6%, and 46.3%, respectively. Middle and high stress groups had higher crude and adjusted odds than the low stress group for all body sites. The association for neck, wrist/hand, and upper back and ankle/foot reports (adjusted odds ratio for high stress ranging from 2.4 to 3.0) were statistically significant. Conclusions We observed a high prevalence of self-reported musculoskeletal symptoms at a number of body sites, which were associated with psychosocial factors and specifically stress as defined by the QPS Nordic 34+ Questionnaire. Am. J. Ind. Med. 53:1032,1039, 2010. © 2010 Wiley-Liss, Inc. 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