• Korean Journal of Poultry Science
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• v.47 no.4
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• pp.219-227
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• 2020

As the earth's average temperature rises, crop and livestock productions are at risk. Chickens are sensitive to heat stress, and increased temperatures may have adverse effects on their production performance and animal welfare. Reliable stress measurements are crucial for heat stress adaptation. Therefore, various measurement methods and biomarkers are used to evaluate poultry stress levels. Heat shock proteins (HSPs) are heat sensitive biological markers that are highly expressed under stress, thereby acting as a cellular thermometer. HSPs also have chaperone activity, which protects cells from heat stress. This review details the role of HSP70 as a molecular chaperone and biomarker for heat stress, which is important for breeding climate-adaptable, thermo-tolerant poultry.

• KOREAN POULTRY JOURNAL
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• v.33 no.6 s.380
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• pp.120-125
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• 2001

육용종계는 체내에서 화학적인 반작용에 의해 일정한 열을 생성한다. 이 열이 체온을 상승시켜 폐사하는 것을 방지하기 위해서 열을 발산해야 한다. 계사온도가 상승하면 열 발산이 어려워져서 닭들은 헐떡거림으로 기낭과 폐로부터 수분을 증발하게 된다. 습도가 높을 경우 헐떡거림으로 열을 발산하는 능력을 제한하게 된다. 계사 내의 온도가 $27^{\circ}C$가 넘어가면 고온스트레스와 산란을 감소시킬 수 있으며 $32^{\circ}C$가 넘어가면 스트레스 증상은 뚜렷해진다. $38^{\circ}C$이상이 되면 폐사가 증가하게 되며 특히 과비된 개체가 더 빨리 더 많이 영향을 받는다. 고온스트레스를 줄이기 위해서는 좋은 관리가 매우 중요하며 더위가 오기 전에 미리 준비하는 것이 필수이다.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2006.10a
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• pp.105-109
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• 2006

[ $500^{\circ}C$ ]에서 30초 동안 급속 열처리 하여 니켈실리사이드를 형성하고 니켈실리사이드의 후속 공정시의 열 안정성을 개선 시키기 위해 $SiO_2$ 박막을 FECVD로 증착하였다. 실리사이드의 열 안정성은 면저항 측정을 통하여 평가하였다. 후속 열처리 시 $SiO_2$ 보호층을 증착한 경우 열 안정성이 개선 되었다. 이 이유를 알아보기 위해 열처리 전후의 스트레스를 측정하였다. 그 결과 후속열처리 시 $SiO_2$ 보호층이 없을 때는 열처리 전과 후의 스트레스 큰 차이가 없었으나 $SiO_2$ 보호층이 있을 매는 스트레스가 크게 감소하였다. 이 스트레스의 감소가 니켈실리사이드의 응집현상을 억제하여 니켈실리사이드의 열 안정을 개선시키는 이유라고 판단된다.

• Journal of agriculture & life science
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• v.50 no.5
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• pp.163-172
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• 2016

Four growing Hanwoo cattle weighing 200±11.7kg were used within 4×4 Latin square design to establish nutrient requirements for Hanwoo growing steers under severe heat stress. The steers were fed four different energy level diets; 100%(control), 100%(E100), 115%(E115) and 130%(E130) of energy levels of growing Hanwoo steers based on total digestible nutrient level suggested by the Korea Feeding Standard for Hanwoo using timothy hay and commercial concentrate. The steers in the control were housed with no stress, whereas the steers in the other groups were under severe heat stress. The severe heat stress significantly decreased(p<0.05) true digestibility of dry matter(i.e. control 81.5% vs E100 79.1, E115 77.0 and E130 76.0, respectively). The severe heat stress and different energy intake levels did not affect blood physiological metabolites and body temperature of the growing steers. Based on changes in average daily gain by different energy intake level, the equation(Y=0.235X+115.03) of energy requirement of growing Hanwoo steers without changes in body weight was calculated, indicating that, compared with the present energy intake suggested by Korean feeding standard, 15.03% of dietary energy for maintenance of growing Hanwoo steers under severe heat stress should be increased.

• 한국노년학
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• v.30 no.3
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• pp.793-802
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• 2010

The purpose of this study was to examine the influence of extreme heat on muscle function and muscle injury marker in elderly women. The subjects of this study were eight post-menopausal elderly women without any metabolic disease. All eight subjects were asked to perform the knee joint isokinetic exercise using isokinetic equipment (cybex) in the laboratory and experimental temperature within laboratory was adjusted to two conditions: extreme heat temperature(33±0.5℃) and normal temperature(20±0.5℃) maintained in 50±3% humidity conditions. Each experimental exercise was monitored and analyzed the change of HSP70, LDH and CK. Muscular functions (peak torque, total work, percentage of peak torque body weight, fatigue index, average power and total work) were significant differences at exercise between temperatural conditions (p<.05). In extreme heat temperature, muscular injury markers (HSP70, LDH and CK) were increased, threfore resulted in significantly higher than normal temperature(p<.05). These results show that extreme heat temperature can decrease muscle function in elderly women.

• Proceedings of the KAIS Fall Conference
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• 2006.05a
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• pp.449-452
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• 2006

본 논문에서는 전장부품에서 중요한 연결 장치인 커넥터의 고장 모드를 분석하기 위한 방법으로 HALT(Highly Accelerated Life Test)를 이용해 관측된 고장 데이터를 기반으로 ReliaSoft사의 소프트웨어인 ALTA PRO를 이용하여 분석하고자 한다. 커넥터를 이루는 주재료는 플라스틱과 금속으로 구성되어 있어 습도에 대한 반응 보다 열 변화와 진동에 의해 고장이 발생 한다. 이러한 커넥터의 특성을 고려하여 HALT는 온도와 진동 스트레스를 이용한 복합 스트레스 시험을 실시하였다. HALT에 사용된 시료는 20핀 커넥터 5개로 74시간 동안 시험하였으며, 9개의 핀에서 부러지는 고장이 관측 되었다. 관측된 고장 데이터를 단일 스트레스에 의한 고장으로 분석하기위해 시험에 사용된 온도와 진동 스트레스를 개별 스트레스로 하여 ALTA PRO를 이용하여 분석하였다. 분석을 위한 수명-스트레스관계식은 스텝 스트레스에 적합한 Cumulative Damage 선택하였으며 Likelihood Function을 이용 최적 분포는 Weibull 분포임을 확인하였다, ALTA Pro를 이용한 분석 결과 열에 대한 Mean Life는 2444.03 시간이며, 진동에 대한 Mean Life는 1784.27시간으로 진동에 대한 Mean Life가 659.76 시간만큼 작은 것을 확인 하였다. 고장 데이터를 이용한 수명 예측에서 Mean Life가 작다는 것은 스트레스에 의해 고장이 빠르게 발생 했다는 것을 의미한다. 가속수명시험을 통해 관측된 커넥터의 고장은 핀이 부러지는 현상이며, 고장에 대한 주요 원인으로 온도 스트레스 보다 Mean Life가 낮은 진동 스트레스인 것으로 판단된다.

• Journal of Digital Convergence
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• v.20 no.4
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• pp.291-299
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• 2022

This study was to verify the effect of the supervisor's abusive supervision on turnover intention and the mediating role of emotional stress and work engagement in the process. The online survey was conducted on 317 employees and the data were analyzed through SPSS Macro and bootstrapping. The results are as follows: the correlation between abusive supervision, emotional stress, work engagement and turnover intention was confirmed to be statistically significant, and dual mediating effect of emotional stress and work engagement was statistically significant. This study showed meaningful results on the path of the abusive supervision and turnover intention. Further studies with longitudinal method and in-depth studies on factors influencing pathways will be needed to verify substantially the dual mediating effect.

• The Journal of the Korea Contents Association
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• v.21 no.3
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• pp.336-351
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• 2021

The purpose of this research is to find out the effects of music therapy activities using preferred music on job stress, work engagement and flourishing of reporters in broadcasting company. The study targets 51 reporters in S city, with the experimental group consisting of 20 reporters from A broadcasting company and the control group composed of 31 reporters from A newspaper company. The experimental group voluntarily listened to preferred music at least three times a day for two weeks, while the control group did not perform any activities. For data analysis, the job stress scale, work engagement scale, and flourishing scale scores of each group were collected right before and after the experiment, and the results of the analysis were as follows. First, the experimental group's job stress decreased, and significant score differences were also shown in comparison with the control group. Second, work engagement also increased by a noticeable difference. Third, in the case of flourishing, the after experiment's average value rose slightly, but the difference was not statistically significant. In conclusion, this research offered implications for the need for a music therapy activity program to recover from reporters' job stress circumstances and discussed the need for further research.

• Proceedings of the KAIS Fall Conference
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• 2009.12a
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• pp.546-549
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• 2009

본 연구는 2008년 1월부터 2008년 12월까지 S 유치원 원아40명(실험군 20명, 대조군 20명)의 뇌파를 검사하여 뉴로피드백 훈련 전과 훈련 후의 스트레스 저항 능력을 보고자 하였다. 훈련 전과 후의 스트레스 저항 능력은 시계열 선형분석을 통하여 비교하였으며, 연구의 결과로 뉴로피드백 훈련을 적용한 집단에서 항 스트레스 지수에서 유의미한 차이를 보였다. 이 결과는 뉴로피드백 훈련이 유아들의 스트레스 저항 능력을 높여 주었으며 정서적 성향에 긍정적인 영향을 미쳤다고 본다.

• KSBB Journal
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• v.18 no.4
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• pp.294-300
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• 2003

In the previous study, we have isolated several vaginal lactobacilli from Korean woman and selected one of them (KLB12) for further study, which was indentified as Lactobacillus fermentum by sequence analysis of 16S rRNA gene. Formulated L. fermentum KLB12 can be used for ecological treatment of bacterial vaginosis. For pharmaceutical formulation, the spray-drying process is required where stress such as high temperature is routinely applied. In this study, we found that heat stress at 60$^{\circ}C$ for 20∼30min reduced the viable cell population of KLB12 by 10$\sub$6/～10$\sub$9/. However, adaptation of KLB12 cells at 52$^{\circ}C$ made them more thermotolerant upon exposure to 60$^{\circ}C$. The level of thermal protection in RSM (reconstituted skim milk) by adaptation in acid (pH 5), cold (4$^{\circ}C$), ethanol (3％), NaCI (0.3M) was also examined. Although not as efficient as the homologous stress, adaptations in both cold and NaCI gave considerable cross protection against heat stress. When chloramphenicol was added during heat adaptation, adaptation effect was abolished. This suggests that de novo protein synthesis is necessary during the adaptation process. Important changes in proteome during heat adaptation was examined with two-dimensional gel electrophoresis.