• Transactions of the Korean Society of Mechanical Engineers A
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• v.22 no.3
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• pp.483-492
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• 1998

An inverse analysis been applied to obtain the flow stress of the material. In this method, a ring-shaped specimen is compressed between two flat tools. This procedure employs, as the object function of inverse analysis, the balance of measured loads and reaction forces calculated by using rigid-plastic finite element method. The balance is explicit scalar function of flow stress which is a function of some unknown constants. For minimizing the balance, Newton-Raphon scheme is used. The friction factor, m, between flat tools and the specimen is determined by using friction area-divided method. The proposed method allows an accurate identification by avoiding the usual assumptions made in order to convert experimental measures into stress-strain relation. In this paper, the proposed method is numerically tested. A commercial pure aluminum was selected, as an example, to apply the method and the results are compared with stress-strain relation obtained by experiments.

• Child Health Nursing Research
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• v.15 no.1
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• pp.71-80
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• 2009

Purpose: This study was done to investigate the effects of an infant massage on physical growth and stress response in preterm babies. Method: A nonequivalent control group with pre-posttest design was used with 56 preterm babies in the NICU of E medical center at Daejeon. Data were collected from July 2004 to May 2005. The intervention was given for 15 minutes, once a day for 7 days. Physical growth was measured by weight, length, head circumference, and stress response was measured by serum cortisol level. Mean, %, paired-test, t-test with the SPSS/W in 16.0 program were used to analyze the data. Results: After the intervention, physical growth variables (weight, length, head circumference) in experimental group were higher than that of the control group. Also, the serum cortisol level in the experimental group was lower than that of the control group. But none of these results were not statistically significant. Conclusion: The results of this study suggest that a 7-day intervention period may not be long enough to confirm the effects of infant massage on physical growth and stress reaction. Therefore it is suggested that a longer period of infant massage should be tested to determine if it is effective in improving the physical growth and stress reduction in preterm babies.

• Journal of Microbiology and Biotechnology
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• v.21 no.10
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• pp.1064-1068
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• 2011

The osmotolerant yeast, Candida magnoliae, which was isolated from honeycomb, produces erythritol from sugars such as fructose, glucose, and sucrose. Erythrose reductase in C. magnoliae (CmER) reduces erythrose to erythritol with concomitant oxidation of NAD(P)H. Sequence analysis of the 5'-flanking region of the CmER gene indicated that one putative stress response element (STRE, 5'-AGGGG-3'), found in Saccharomyces cerevisiae, exists 72 nucleotides upstream of the translation initiation codon. An enzyme activity assay and semiquantitative reverse transcription polymerase chain reaction revealed that the expression of CmER is upregulated under osmotic and salt stress conditions caused by a high concentration of sugar, KCl, and NaCl. However, CmER was not affected by osmotic and oxidative stress induced by sorbitol and $H_2O_2$, respectively. The basal transcript level of CmER in the presence of sucrose was higher than that in cells treated with fructose and glucose, indicating that the response of CmER to sugar stress is different from that of GRE3 in S. cerevisiae, which expresses aldose reductase in a sugarindependent manner. It was concluded that regulation of CmER differs from that of other aldose reductases in S. cerevisiae.

• Animal cells and systems
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• v.6 no.1
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• pp.1-12
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• 2002

A role of Src family protein Tyrosine kinases (SFK) as mediators of receptor-ligand initiated responses is well established. Well documented, but less well understood is the role of SFK in cellular reaction to stresses. Evidence from the wide variety of experimental systems indicates that SFK mediate responses to all major classes of stress, including oxidation, DNA damage, mechanical impacts, and protein denaturing. SFK may be activated by stresses directly or via regulatory circuits whose identity is not yet fully understood. Depending on the cell type and the nature of activating stimulus, SFK may activate known downstream signaling cascades leading to cell survival, proliferation, cytoskeletal rearrangement, and apoptosis; the identity of these cascades is discussed. As in the case of receptor-initiated signaling, roles of individual SFK in various stress response may be redundant or non-redundant. Although signals generated by different stresses are generally transduced via distinct SFK pathways, these pathways may overlap or exhibit crosstalk. In some cell types stress-induced activation of SFK promotes survival and inhibits apoptosis, whereas the opposite may be true for other cell types. Stress responses constitute a new and rapidly developing area of SFK-mediated signaling.

• Journal of Distribution Science
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• v.19 no.10
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• pp.99-109
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• 2021

Purpose: Retail workers have a role in attending to customers better, not only making sales to them. In this regard, this research focuses on having a clear understanding of the effects of emotional factors and job stress on mental health for retail sales workers. Research design, data and methodology: The present research conducted both a qualitative textual analysis and interview. This research method is quite useful because it relates the information collected with the research gap. Qualitative data is time-consuming type of data to analyze since it involves interpreting words rather than numbers. Results: The findings showed that emotional labor and stress may not only cause mental harm to the employees but can result in adverse reaction to the customers. Retail employees need to express their true emotions and avoid pretending to be helped with a clear understanding of their needs. Conclusion: This study conclude that motional labor and stress to the retail workers is a real issue that has affected many people around the globe and there is a need to conduct more research on the issue to help employees serve customers much better. Stress among sales workers results to poor working morale and thus affects the entire organization at large.

• Journal of Animal Reproduction and Biotechnology
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• v.36 no.4
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• pp.220-229
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• 2021

Lonicera caerulea (Honey berry, HB) has been used in medical treatment in Russia, Japan, China and Korea. It has high level of vitamin C and polyphenolics. Polyphenolics can improve anti-inflammatory effect and prevent cancer, diabetes mellitus type 2. Also, Vitamin C is a representative anti-oxidant. however, it is still unknown what effect it will have on the oxidation stress of the reproductive system. In previous studies, ROS can be produced when it is exposed to heat stress and has negative effect on sperm's maturation, capacitation, hyperactivation, acrosome reaction and fusion of egg and sperm. Therefore, the purpose of this study is to investigate the antioxidant effects of L. Caerulea on the sperm and mice. At first, it conducted using ICR mouse (n = 20) for 4 weeks. There are four groups of mice (n = 5 per group). Also, L. Caerulea was taken by oral gavage. Group I (control) kept at 23℃-27℃ and administer D.W (0.5 mL/day), Likewise, Group II (HB) kept at room temperature but gave HB (250 mg/kg, 0.5 mL/day), Group III (HB + HS) received heat stress (40℃) using hyperthermia induction chamber and gave HB at same dose. and Group IV (HS) exposed heat stress only. Mainly, we showed degree of gene expression using Western blot in SOD, HSP 70, 17β-HSD and Real-time PCR. It can find correlation between intracellular activity like steroid hormone, apoptosis under ROS and antioxidant activity of L. Caerulea.

• Journal of Environmental Health Sciences
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• v.30 no.3
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• pp.283-292
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• 2004

Valid evaluation of community reaction to road-traffic noise exposure is important for the policy making and quality of life. The purpose of this study is to evaluate the relationship between community reaction and nighttime road-traffic noise. The study measured nighttime roadside noise caused by high traffic which is greater than LAeq(22:00-07:00) 65dB(A) and lower than 65dB(A) at Chonju city, from March to April, 2003. Three hundred sixty seven subjects, aged from 20 to 65, were selected from those who are residing close to the major roads. They were asked to answer the questions regarding noise source, stress(PWI-SF), annoyance, disturbance of specific activity, disturbance of sleep, somatic symptom, and four suggested confounding factors. The relationship between annoyance, somatic symptom and noise exposure was not significant. Adjusted odds ratio(95% C.I.) for disturbance of communication　 and disturbance of attention and rest　 were 1.59(1.03-2.71), 1.64(1.06-2.81), respectively. On the other hand sleep disturbance　 was indicated as 1.34(0.77-2.32). The results suggested that federal policy-making about road-traffic noise should consider community reaction evaluated by various perspective including annoyance, disturbance of specific activity, disturbance of sleep, and confounding factors.

• Korean Journal of Metals and Materials
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• v.49 no.8
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• pp.664-670
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• 2011

3-ply Mg/Al/STS clad-metal was fabricated by the roll bonding process. An interfacial reaction layer was formed at the Mg/Al interface at and above $300^{\circ}C$ whereas no interfacial reaction layer was observed up to $400^{\circ}C$. The effect of the interfacial reaction layer on the mechanical and fracture properties in clad metals after heat treatments were investigated The chemical compositions were analyzed at the Mg/Al interface by an Energy dispersive X-ray analysis (EDX). A tension test was performed to examine the interfacial cracking properties. The Mg layer fractured first, causing a sudden drop of the stress and Al/STS layer continued to deform until the final fracture. Periodic cracks and crack propagation was observed at the reaction layer between Mg and Al.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.111-111
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• 2017

The development and productivity of maize (Zea mays L.) is frequently impacted by water scarcity, and consequently to increased drought tolerance in a priority target in maize breeding programs. To elucidate the molecular mechanisms of resistance to drought stress in maize, RNA-seq of the public database was used for transcriptome profiling of the seedling stage exposed to drought stress of three levels, such as moderate, severe drought stress and re-watering. In silico analysis of differentially expressed genes (DEGs), 176 up-regulated and 166 down-regulated DEGs was detected at moderated stress in tolerance type. These DEGs was increasing degradation of amino acid metabolism in biological pathways. Six modules based on a total of 4,771 DEGs responses to drought stress by the analysis of co-expression network between tolerance and susceptible type was constructed and showed to similar module types. These modules were discriminated yellow, greenyellow, turquoise, royalblue, brown4 and plum1 with 318, 2433, 375, 183, 1405 and 56 DEGs, respectively. This study was selected 30 DEGs to predicted drought stress response gene and was evaluated expression levels using drought stress treated sample and re-watering sample by quantitative Real-Time Polymerase Chain Reaction (qRT-PCR). 23 genes was shown increasing with drought stress and decreasing with re-watering. This study contribute to a better understanding of the molecular mechanisms of maize seedling stage responses to drought stress and could be useful for developing maize cultivar resistant to drought stress.

• Journal of Oral Medicine and Pain
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• v.32 no.1
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• pp.57-67
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• 2007

In currently, stress diseases are increased that present several sign and symptoms. Under stress condition, there are dry mouth, burning mouth syndrome, oral mucosa diseases and halitosis more frequently. Changing of salivary proportion is checked in almost patients with changing of function and structure in salivary gland. This study purpose are what effect stress does on salivary gland, and a-amylase on salivary gland. This study was resulted that 1. Under restraint stress, acinar cells are vacuolization and changing of intercellular spaces are separated, and peripheral tissues of duct are changed 2. Acinar cells were shrunk after 3 hours under restraint stress, intercellular space was separated after 6hours, peripheral tissues of duct started to change after 72 hours, and acinar cells and peripheral tissues of duct were all severely changed after 168hours. 3. In immunohistochemical study, amylase reaction was showed partially and irregularly after 3 hours, was getting little milder after 6 hours. And amylase reaction was gradually increased from the time of 12 hours after experiment up to the time of 48 hours after experiment. But after 168 hours, amylase appearance was diminished. According this result, emotional stress can change of salivary gland structure, and amylase secretion, the important digestive enzyme from salivary gland is changed and it is supposed to make digestive disorder and to make halitosis efficiency. So, we need to study about secretion of amylase.