• Earthquakes and Structures
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• v.24 no.1
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• pp.53-64
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• 2023

Earth fissures with several kilometers will inevitably approach or cross the metro line, significantly threatening the safety of the underground structure in the earth fissure site. However, the influence of the earth fissure site's amplification effect on the metro station's dynamic response is still unclear. A representative earth fissure in Xi'an was taken as an example to establish a numerical model of a metro station in the earth fissure site. The dynamic response characteristics of the metro stations at different distances from the earth fissure under various seismic waves were calculated. The results show that the existence of the earth fissure significantly amplifies the dynamic response of the nearby underground structures. The responses of the axial force, shear force, bending moment, normal stress, horizontal displacement, inter-story drift, and relative slip of the metro station were all amplified within a specific influence range. The amplification effect increases with the seismic wave intensity. The amplification effect caused by the earth fissure has relatively weak impacts on the axial shear, shear force, bending movement, normal stress, and horizontal movement; slightly larger impacts on the inter-story drift and acceleration; and a significant impact on the relative slip. The influence ranges of the axial force and normal stress are approximately 20 m. The influence ranges of the acceleration and inter-story drift can reach 30 m. Therefore, the seismic fortification level of the underground structure in the earth fissure site needs to be improved.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.4
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• pp.336-345
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• 2012

In crack growth life, uncertainties are caused by variance of geometry, applied loads and material properties. Therefore, the reliability estimation for these uncertainties is required to keep the robustness of calculated life. The stress intensity factors are the most important variable in crack growth life calculation, but its equation is hard to know for complex geometry, therefore they are processed by the finite element analysis which takes long time. In this paper, the response surface is considered to increase efficiency of the reliability analysis for crack growth life of a turbine wheel. The approximation model of the stress intensity factors is obtained by the regression analysis for FEA data and the response surface of crack growth life is generated for selected factors. The reliability analysis is operated by the Monte Carlo Simulation for the response surface. The results indicate that the response surface could reduce computations that need for reliability analysis for the turbine wheel, which is hard to derive stress intensity factor equation, successfully.

• Korean Journal of Acupuncture
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• v.26 no.4
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• pp.39-52
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• 2009

Objectives : Cue reactivity is a key factor that modulates motivational goal-directed behavior associated with compulsive drug-taking and relapse. We investigated whether acupuncture attenuated the skin conductance response and the heart rate response to smoking-related visual cues in smokers. Methods : Twenty-nine smokers were treated with real acupuncture (RA) or sham acupuncture (SA). The stress response inventory was measured on the 5th day after quitting smoking. The skin conductance response and the heart rate were measured to evaluate the autonomic changes to the smoking related visual cues on the same day. Results : The sympathetic alterations in skin conductance and the heart rate induced by the smoking-related visual cues were significantly lower in the RA group, as compared to the SA group. The stress response inventory, such as somatization and frustration, in the RA group was significantly lower than that of the SA group. Conclusions : Acupuncture ameliorated the stress symptoms as well as the sympathetic activation to smoking cues during withdrawal. These findings indicate that acupuncture might be a useful tool in smoking cessation by inhibiting smoking cues-induced autonomic responses.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.29 no.2
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• pp.108-115
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• 2003

Suppression of cellular immunity is the host responses to surgical stress. When the body is exposed to surgical stress, decreased immunocyte function is one of the surgical stress-induced biologic responses. In all patients exposed to the surgical stress, peripheral blood lymphocyte numbers and function were suppressed until at least 2 weeks postoperatively. This immunosuppression was mainly due to a decrease of helper-inducer T cells, cytotoxic T cells, natural killer cells, and an increase of suppressor T cells. The blood levels of interleukin-6(IL-6) cytokine increase in response to surgical stress and cause an increase of so-called acute phase reactants, including C-reactive protein(CRP). In the previously damaged patients group, expected to early stress expose, immunosuppression was more developed than other normal groups. Cellular immunosuppression by surgical stress was mainly due to an increase of lymphocyte subsets that depress cellular immunity coupled with a decrease of the subsets that promote it. Overproduction of CRP in response to surgical stress may play an important role in the development of immunosuppression.

• Journal of the Korean Society for Heat Treatment
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• v.5 no.4
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• pp.201-208
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• 1992

An experimental study of the constitutive response of precipitation-strengthened Al-0.55wt% Zr alloy, which consists of an Al matrix precipitation-strengthened by coherent particles, ${\beta}^{\prime}(Al_3Zr)$ with $L1_2$ structure has been performed. The deformation response of the materials has been examined by stress relaxation test at 573K, 623K and 673K. It was found that there exist the threshold stress during stress relaxation and threshold stress results from the presense of ${\beta}^{\prime}(Al_3Zr)$ particles. The ratio of threshold stress and Orowan stress decreased gradually with increasing temperature. The resistance to climb-pass of particles was independent of particles size for a fixed volume fraction although the threshold for bowing and particles cutting are sensitive to the particles dimensions. The smaller particles cutted by dislocations. This behavior of dislocations in this alloy was explained in terms of the small value antiphase boundary energy. The dislocation networks wrere more extensive in spesimens subjected to stress relaxation and there were numerous areas that have a high denstiy of jogged dislocation. This experiment results indicate that the rate controlling stress relaxation process is the climb of edge dislocation over particles.

• BMB Reports
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• v.29 no.5
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• pp.393-397
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• 1996

Sprague-Dawley male rats (150 g) were chronically treated with 5 v/v % ethanol admixed with nutritionally complete liquid diet and fed ad libitum for 3 weeks. Controls were pair fed with the isocaloric sucrose liquid diet. One half of each group was exposed to cold stress at $4^{\circ}C$ either for 24 h (for determination of mRNA by in situ hybridization) or for 48 h (for determination of enzyme activity). Chronic ethanol treatment (ethanol) did not affect tyrosine hydroxylase (TH) mRNA level in locus coeruleus (LC) of brain and adrenal medulla (AM) compared to controls. Cold stress showed strong increase of TH mRNA level in LC and AM compared to controls. Pretreated ethanol reduced the increased TH mRNA level by cold stress in LC and AM. Ethanol did not affect TH activity in LC and adrenal glands (adrenals). Cold stress increased TH activity in LC but not in adrenals. Pretreated ethanol did not reduce the increased TH activity by cold stress in LC but this result was not shown in adrenals. It is suggested that ethanol does not affect the message level and enzyme protein level for TH in LC and AM in normal rat. It is also hypothesized that pretreated ethanol reduces the magnitude of acute cold stress response, that is induction of TH mRNA in LC and AM, and does not reduce the increased TH enzyme protein that is also acute cold stress response in LC.

• Korean Journal of Agricultural Science
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• v.46 no.3
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• pp.637-643
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• 2019

The aim of the present study was to evaluate the effect of the induced heat stress on physiological response and serum biochemical parameters involving glucose, cholesterol, blood urea nitrogen (BUN), non-esterified fatty acids (NEFA), and cortisol in Holstein calves. Ten calves were kept in a climate controlled room (air temperature $37^{\circ}C$ and 90% humidity from 09:00 to 19:00) for three days. Those animals were given a one-day adaptation period. During the treatment period, we measured the skin temperature six times. Following the treatment periods, blood samples were collected before the experiment began (09:00) and at the end of the stress period (19:00). To aid analysis of the biochemical parameters, also we monitored the rectal temperature. The results, exhibited that both rectal and skin temperature showed increase in the heat stress-induced animals as compared with unstressed animals. Moreover, we noticed that the levels of BUN and NEFA increased in the blood serum of heat stress induced animals when compared with un-stressed ones. From these results, we concluded that the physiological and biochemical changes in the calves were induced by heat stress. Hence, the present study findings could be employed as base line data for development of stress reduction techniques in the dairy industry.

• Journal of Korean Biological Nursing Science
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• v.26 no.2
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• pp.99-110
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• 2024

Purpose: This study reviewed the pathophysiological mechanisms of cellular aging caused by psychological stress and aimed to establish a biobehavioral theoretical framework for nursing interventions to promote autonomic balance based on these mechanisms. Methods: A comprehensive literature review was conducted. Results: A review of the literature showed that the stress response increases the secretion of catecholamines and glucocorticoids, resulting in a greater allostatic load. This load induces inflammatory reactions and oxidative stress, shortening telomere length and damaging mitochondrial DNA, which can lead to cellular aging. Based on this mechanism, a biobehavioral theoretical framework for nursing interventions was established. This framework focuses on delaying or inhibiting the cellular aging process by acting on the stress response stage and improving autonomic balance. Conclusion: According to the proposed biobehavioral theoretical framework, stress-relieving nursing interventions may act on the mechanism of cellular aging caused by stress responses. We believe that this framework could expand our understanding of the biobehavioral aspects of stress and would facilitate efforts to use biomarkers to evaluate the effectiveness of stress-related nursing interventions at the cellular level.

• Korean Journal of Psychosomatic Medicine
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• v.17 no.1
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• pp.8-14
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• 2009

Objectives : The purpose of this study was to investigate the various aspects of stress in patients with chronic prostatitis. Methods : Thirty two chronic prostatitis patients meeting the criteria of NIH-category III were compared with sixty four controls. Data pertaining to the source of, response to, and coping with stress, as well as chronic prostatitis symptom index were collected using a self-report questionnaire. The questionnaire consisted of a Global Assessment of Recent Stress(GARS), Stress Response Inventory(SRI), Ways of Coping Checklist(WCC), in addition to the NIH-CPSI. Results : From the results of GARS subscales, the scores of changes in relationship, sickness or injury and financial were significantly higher in patients with chronic prostatitis than normal controls. Chronic prostatitis patients had greater amplification of somatization, depression and anger in SRI and significantly lower score in ways of coping checklist compared with controls. In the NIH-CPSI of chronic prostatitis patients, the degree of symptom played a role in depression as stress response item and significant negative correlationship between the symptom point and problem focused, seeking social support coping strategy was observed. Conclusion : These results show that patients with chronic prostatitis have greater stress, higher stress response and insufficient coping strategy. Therefore, these efforts should be considered that enhancing healthier coping strategy and evaluation and management of stress experienced by chronic protatitis patients

• Bulletin of Food Technology
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• v.22 no.4
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• pp.700-709
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• 2009