• Title/Summary/Keyword: Normal Stress

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Stress Analysis in Nodal Zone by using Complementary Pole Method (Complementary Pole을 이용한 Nodal Zone의 응력해석)

  • Kang, Sung-Hun;Hong, Sung-Gul
    • Proceedings of the Korea Concrete Institute Conference
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    • 2010.05a
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    • pp.53-54
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    • 2010
  • This study investigates stress analysis in nodal zone by using Complementary Pole Method (CPM). The CPM is convenient tools for the stress or strain analysis since it enables to express parallel directions of the normal stress or strain on the Mohr Circle. In this study, it is suggested to use of CPM to analysis stress or strain in the field of Concrete Plasticity.

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Comparison analysis of psychological and biochemical indices of chronic life stress

  • Kim, Dongsoo;Park, Se-kwon;Chung, Yeon-Soo;Moon, Soo-Jong
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2003.10b
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    • pp.162-162
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    • 2003
  • The psychological and biochemical stress responses of healthy men and women were measured under the normal situation. Experimental subjects, who were cadets of the Korea Air Force Academy, were selected by the random sampling. Quantitative scaling of the psychological stress was obtained by life stress test(Cheon et al, 2000) and Minnesota Multiphasic Personality Inventory(MMPI).(omitted)

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Results in Stress Test in the Ankle Stability of Young Men in Korea (한국의 젊은 남성에서 족관절 안정성에 대한 부하검사시의 결과)

  • Lee, Kyung-Tai;Lee, Young-Koo;Choi, Byung-Ok
    • Journal of Korean Foot and Ankle Society
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    • v.12 no.1
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    • pp.36-40
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    • 2008
  • Purpose: The purpose of this study is to find out the normal results in ankle on varus stress, valgus stress, and anterior draw stress in young men in korea. This would be helpful as the basic data of measuring of ankle instability for operational indication. Materials and Methods: Varus and Valgus stress anteroposterior radiographs and Anterior drawing stress lateral radiographs of 600 normal ankles were reviewed. First, A line parallel was drawn parallel to the articular surface of the distal tibia, and another line was drawn parallel to the articular surface of the talus on anteroposterior radiographs. The interior angle that subtended by these two lines was measured. Second, the reference point is located at the posterior border of the tibia, and the shortest distance from this point to the proximal posterior articular surface of the talus is measured. Results: There were 300 males and 600 ankles. The mean age overall was 21 years (19-22 years) old. The mean length of ankle on anterior draw stress was $5.54{\pm}3.33\;mm$. The mean a interior angle of ankle on varus stress was $0^{\circ}-8.93^{\circ}$, and on valgus stress $0^{\circ}-7.78^{\circ}$. Conclusion: We can consider for operational indication at over the 8.87 mm on anterior draw stress, over the $8.93^{\circ}$ on varus stress, and over the $7.78^{\circ}$ on valgus.

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Response of Ascorbate Peroxidase and Dehydroascorbate Reductase in Lettuce (Lactuca sativa L.) Leaves Exposed to Cold Stress (저온 처리한 상추의 잎 내에서 ascorbate peroxidase와 dehydroascorbate reductase의 반응)

  • Kang, Sang-Jae
    • Journal of Life Science
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    • v.18 no.12
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    • pp.1705-1711
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    • 2008
  • To investigate the relationship between cold stress and the activity of ascorbate peroxidase(APX), dehydroascorbate reductase (DHAR), mRNA expression level of two enzymes, hydrogen peroxide content was studied in lettuce leaves under stress condition imposed by cold stress at $4^{\circ}C$ for 24 hr in the dark and following recovery at $20^{\circ}C$ from cold stress. Hydrogen peroxide content increased gradually in lettuce leaves during cold stress, but decreased slightly following recovery from cold stress. Soluble protein content, however, decreased gradually during cold stress, and then rapidly returned to normal levels following recovery. Total chlorophyll content decreased gradually during cold stress, and then keep constant following recovery. The patterns of chlorophyll a and b content similar to that of total chlorophyll content, and carotenoid content didn't change. The ratio of chlorophyll a and total chlorophyll was increased during cold stress, but decreased with rapid during cold stress, and then the ratio returned to normal levels following recovery. During cold stress, the activity of APX and DHAR in the lettuce leaves increased dramatically, and also transcript levels of mRNA of APX and DHAR, as determined by probing 32P-labeled single stranded RNA of APX and DHAR, highly increased and returned to normal levels following recovery, respectively. Relationship between APX and DHAR activity and hydrogen peroxide highly related ($R^2$=0.8715 and 0.8643), whereas between hydrogen peroxide and total chlorophyll content and soluble content related reversely ($R^2$=0.5021 and 0.8915).

The Relationship between Perceived Stress and Coping Strategies in Patients with Chronic Low Back Pain (만성요통 환자들에서 스트레스지각과 대응전략 간의 관계)

  • Shin, Yoon-Sik;Koh, Kyung-Bong
    • Korean Journal of Psychosomatic Medicine
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    • v.10 no.1
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    • pp.18-26
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    • 2002
  • Objectives : The object of this study was to investigate the relationship between coping strategies and perceived stress or pain discomfort in patients with chronic low back pain. 80 patients with chronic low back pain and 100 normal controls participated in this study. Methods: Global assessment of recent stress (GARS) scale and Stress Response Inventory (SRI) were used to measure perception for stressors and stress responses. Coping scale and pain discomfort scale were used to measure coping strategies and pain perception. Results : Scores of perceived stress related to work or job, interpersonal relationship, changes in relationship, sickness or illness and the total scores on the GARS scale were significantly higher in those with chronic low back pain than normal controls. Scores of the SRI fatigue subscale scored significantly higher in those with chronic low back pain than normal controls. No significant difference was found on total scores of the pain discomfort scale between those with chronic low back pain and normal controls. The patients with chronic low back pain scored significantly higher on planful problem solving and positive reappraisal than normal controls. In the patient group, pain perception had significant positive correlations with total scores of the SRI and scores of stress perception related to illness or injury. The extent of escape-avoidance showed significant negative correlations with age, whereas the extent of distancing or escape-avoidance had significant negative correlations with the level of education. Significant difference was also found in accepting responsibilities between male subjects and females. However, no significant correlations were found between coping strategies and perceived stressors, stress responses or pain perception. Conclusion : The results suggest that patients with chronic low back pain were more likely to use more active coping strategies than normal controls, though the former had more perception for stressors than the latter. It was also found that coping strategies used by the patients were associated with sociodemographic factors, but that they were not associated with perceived stressors, stress responses or pain perception.

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Genome Wide Expression Analysis of the Effect of Pinelliae Rhizoma Extract on Psychological Stress (반하(半夏)가 스트레스로 인한 생쥐의 뇌조직 유전자변화에 미치는 영향 연구)

  • Jeong, Jong-Hyo;Cho, Su-In;Song, Young-Gil;Kim, Ha-Na;Kim, Kyeong-Ok
    • Journal of Oriental Neuropsychiatry
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    • v.26 no.1
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    • pp.63-78
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    • 2015
  • Objectives: Pinelliae Rhizoma has traditionally been used as an anti-depressant in oriental medicine. This study is to investigate the effect of Pinelliae Rhizoma extract (PRe) on psychological stress in genome wild expression of mice. Methods: After giving physical stress to mice, PRe was orally administered with 100 mg/kg/day for five days. After extracting whole brain tissue from the mice, their genome changes were observed by micorarray analysis method. The genome changes were analyzed by IMAGENE 4.0, TREEVIEW, FatiGo algorithems, BOND database, cytoscape program, etc. Results: 1. PRe administered group were remained at normal level; 60% of increase was shown in expressed genes by physical stress, and 65% of decrease was shown in expressed genes by psychological stress. 2. Genes with increased expression in control group that remained at a normal state in PRe administered group were involved with the gene of a cellular metabolic process on biological process, protein binding on molecular function, and cell part on cell composition. The pathway was found to be cytokin-cytokin receptor interaction. 3. Genes with decreased expression in control group that remained at a normal state in PRe administered group were involved with the gene of a cellular metabolic process on biologiacl detail and coupled ATPaes activity on molecular function. This gene related path was Ubiquintin mediated proteolysis etc. 4. Core node genes analyzed by protein interaction network were Vinculin, Cell sdivision cycle 42 homolog (S. cerevisiae) etc. They played an important role in maintaining cytoskeleton and controlling cell cycle. Conclusions: Several genes were up-regulated and down-regulated in response to psychological stress. The expression of most of the genes that were altered in response to psychological stress was restored to normal levels in PRe treated mice. When the interaction network information was analyzed, the recovery of the core node genes in PRe treated mice indicates that this final set of genes may be the effective target of PRe.

The Effect of Cement Milk Grouting on the Deformation Behavior of Artifcial Rock Joints (시멘트현탁액 주입에 의한 신선한 암석절리의 역학적 특성 변화)

  • 김태혁;이정인
    • Tunnel and Underground Space
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    • v.10 no.2
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    • pp.180-195
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    • 2000
  • Grouting has been practiced as a reliable technique to improve the mechanical properties of rock mass. But, the study of ground improvement by greeting is rare especially in jointed rock mass. In this study, joint compression test and direct shear test were performed on pure rock joint and cement milk grouted rock joint to examine the grouting effect on the property of rock joint. In the pure rock joint compression test, joint closure varied non-linearly with normal stress. But after cement milk grouting, the normal deformation characteristics of the joint was linear at the low normal stress level. As normal stress increased. deformation of the sample rapidly increased due to the stress concentration at the joint asperities. Peak shear strength of the grouted joint in low normal stress was higher than that of non-grouted joint due to the cohesion, decreased exponetially as the grout thickness increased. Thus after cement milk grouting, the failure envelope modified to a curve that has cohesion due to grout material hydration with decreased friction angle. Shear stiffness and peak dilation angle of the grouted joint decreased as the grout thickness increased. The peak shear strength from the direct shear test on grouted rock joint was represented by an empirical equation as a fuction of grout thickness and roughness mean amplitude.

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Effect of Chicory Extract on the Lipid Metabolism and Oxidative Stress in Rats (흰쥐의 지질대사 및 산화적 스트레스에 미치는 치커리 추출물의 영향)

  • 차재영;조영수;김대진
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.30 no.6
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    • pp.1220-1226
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    • 2001
  • This study was conducted to investigate the effect of water-soluble extract from roasted chicory on the lipid metabolism and oxidative stress in male Sprague-Dawley rats. The experimental groups were divided into three groups ; the normal group, the cholesterol group and the chicory group. Roasted chicory extract was supplemented at 5.0% (w/w) level in the cholesterol diet. Concentration of total cholesterol in serum was significantly higher in the cholesterol group than in the normal group, but this increase in the cholesterol group was significantly decreased by the cholesterol diet supplemented with chicory extract. Concentration of HDL-cholesterol in serum was significantly lower in the cholesterol group than in the normal group, but this decrease in the cholesterol group tended to increase in the chicory group. However, concentrations of triglyceride, phospholipid and nonesterified fatty acid in serum were not significantly different among the groups. Concentrations of triglyceride and cholesterol in liver were significantly higher in the cholesterol and chicory groups than in the normal group. Feces weight and the excretion of cholesterol and bile acid into feces were significantly higher in the chicory group than in other groups. Concentrations of thiobarbituric acid reactive substances (TBARS) in homogenates and microsomal fractions of liver were not significantly different among the groups. On the other hand, concentration of 8-hydroxydeoxyguanosine (8-OHdG) as an useful marker of oxidative stress in urine was lower in the chicory group than in other groups. Concentration of serum glucose was signnificantly lower in the cholesterol group than in the normal group, but that of the chicory group was significantly higher than in the normal group. These results demonstrated that dietary chicory extract exerted the decreasing effect of cholesterol level and oxidative stress in cholesteral-fed rats.

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A Study on Body Image Perception and Obesity Stress by the Degree of Obesity in College Women

  • Lee, Ji-Eun;Kim, Jung-Hyun;Jung, In-Kyung
    • Preventive Nutrition and Food Science
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    • v.14 no.2
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    • pp.116-122
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    • 2009
  • The principal objective of this study was to assess the weight control behavior, body shape satisfaction, and obesity stress depending on the degree of obesity in college students who applied for a weight control program. The average BMI of the participants was $21.4\;kg/m^2$ which was in the normal range, and 76.3% of the participants were of normal body weight. Ideal BMI in this participant was $18.1\;kg/m^2$, which is in the underweight range. In terms of body perception, participants generally overestimated their body weight. The overweight and normal weight groups were less satisfied with their body shape than was the underweight group. The overweight group also expressed fears of showing their bodies to others. Additionally, the overweight and normal groups exhibited higher obesity stress than the underweight group. 97.0% of participants were interested in weight control as a way to improve their appearance. They usually obtained their weight control information from the internet and mass media. More than 80% of participants had weight control experience, having undergone weight control attempts for duration of less than a month. However, after the discontinuation of weight control efforts, these participants regained the weight. As a consequence, they were generally unsatisfied with the outcomes of weight control programs. This study demonstrated that the college women who had applied for the weight control program were unsatisfied with their body shape owing to distorted notions of the ideal body shape, and these women had generally undertaken frequent efforts to control their body weights. These results underline the importance of educating college-aged women on proper body perception and the maintenance of healthy body weight and shape.

An Evaluation of Interface Shear Strength between Geosynthetic Clay Liner and Geomembrane (토목섬유 점토 차수재(GCL)와 지오멤브레인(GM)의 접촉 전단강도 평가)

  • 서민우;김동진;박준범;박인준
    • Journal of the Korean Geotechnical Society
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    • v.18 no.4
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    • pp.137-146
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    • 2002
  • Geomembrane, compacted clay liner, and geosynthetic clay liner (GCL) are widely used to prevent leachate from leaking to adjacent geo-environment at a municipal solid waste (MSW) landfill. Interface shear strength between GCL and geomembrane installed at a landfill side slope is important properties for the safe design of side liner or final cover systems. The interface shear strength between two geosynthetics was estimated by a large direct shear test in this study. The shear strength was evaluated by the Mohr-Coulomb failure criterion. The effects of normal stress, hydration or dry condition, and a hydration method were investigated. The test results show that the interface shear strength and shear behavior varied depending up on the level of normal stress, the type of geosynthetic combinations, and a hydration method. When GCLs were sheared after being hydrated under 6kPa loading, the results were consistent with those published by other researchers. Summaries of friction angles, normal stress and hydration condition is presented. These friction angles could be used as a reference value at a site where similar geosynthetics are installed.