• 한국정보통신학회논문지
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• 제12권5호
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• pp.809-814
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• 2008

스트레스를 측정하는 방법에 대한 연구는 끊임없이 진행되고 있다. 이토록 연구가 계속 진행되고 있다는 것은 우리의 삶에 항상 존재하면서도 해결하기 쉽지 않은 문제이기 때문이다. 스트레스에 대한 개념 정립이 아직 확실하지 않고, 다양한 해석을 하고 있기 때문에 접 근방법도 다양하다. 그리고 개인에 따른 스트레스 반응의 차이가 많고, 여러 가지 요인들이 관여하기 때문이다. 본 논문은 심리적 영향과 생체적 영향을 통합해서 지수로 나타내어 스트레스에 대한 요인을 분석하고 해석 할 수 있는데 도움이 될 수 있는 변형 지수 알고리즘을 소개한다. 통계 자료와 특정 집단에서 이용되고 있는 측정도구를 중심으로 스트레스의 정도를 지수로 표현하는 알고리즘을 연구하였다.

• Journal of Microbiology
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• 제41권3호
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• pp.248-251
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• 2003

Glutathione (GSH) is an important factor in determining tolerance against oxidative stress in living organisms. It is synthesized in two sequential reactions catalyzed by ${\gamma}$-glutamylcysteine synthetase (GCS) and glutathione synthetase (GS) in the presence of ATP. In this work, the effects of three different oxidative stresses were examined on GSH content and GSH-related enzyme activities in the fission yeast Schizosaccharomyces pombe. GSH content in S. pombe was significantly enhanced by treatment with hydrogen peroxide, ${\beta}$-naphthoflavone (BNF) and tert-butylhydroquinone (BHQ). Simultaneously, they greatly induced GCS and GS activity. However, they did not have any effects on glutathione reductase activity. These results suggest that GCS and GS activities in S. pombe are up-regulated by oxidative stress.

• Asian-Australasian Journal of Animal Sciences
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• 제11권6호
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• pp.751-754
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• 1998

Heterophil (H) to lymphocyte (L) ratios and durations of tonic immobility (TI) were measured to assess stress and fear responses, respectively, in broiler chickens provided either 12 h of natural lighting (12L) or 12 h natural lighting and 12 h of supplementary lighting (24L). Birds illuminated 24L had greater H/L ratios and TI durations than their 12L counterparts. Neither age, sex nor cage level had significant effect on TI reactions.

• 약학회지
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• 제52권3호
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• pp.212-218
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• 2008

Manganese is a naturally occurring element which is widespread in the environment. Also, manganese is an essential trace element and plays a key role in important biological reactions catalyzed by enzymes. However, exposure to high levels of manganese can cause toxicity in neurone and inhalation system, also damage in various tissues. We investigated the toxicity induced by manganese compound ($MnCl_2$) in cultured rat cardiomyocytes. Treatment of manganese to cultured cardiomyocyte led to cell death, reactive oxygen species (ROS) increase, and cytosolic caspase-3 activation. The ROS increase was related with the decreased level of glutathione. Expressions of ROS related genes such as heme oxygenase-1, thioredoxin reductase, and NADH quinone oxidase were significantly induced in manganese treated cells. These results suggest that manganese induce oxidative stress and apoptosis in cardiomyocytes, and may be the one of risk factors to cause heart dysfunction in vivo.

• Steel and Composite Structures
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• 제11권1호
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• pp.21-38
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• 2011

This study examines the influence of curved, steel, I-girder bridge configuration on girder end reactions and cross frame member forces during seismic events. Simply-supported bridge finite element models were created and examined under seismic events mimicking what could be experienced in AASHTO Seismic Zone 2. Bridges were analyzed using practical ranges of: radius of curvature; girder and cross frame spacings; and lateral bracing configuration. Results from the study indicated that: (1) radius of curvature had the greatest influence on seismic response; (2) interior (lowest radius) girder reactions were heavily influenced by parameter variations and, in certain instances, uplift at their bearings could be a concern; (3) vertical excitation more heavily influenced bearing and cross frame seismic response; and (4) lateral bracing helped reduce seismic effects but using bracing along the entire span did not provide additional benefit over placing bracing only in bays adjacent to the supports.

• Clinical and Experimental Pediatrics
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• 제64권8호
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• pp.393-399
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• 2021

Food allergies and food-induced anaphylaxis are important health problems. Several cofactors modulating the onset of anaphylaxis have been identified. In the presence of cofactors, allergic reactions may be induced at lower doses of food allergens and/or become severe. Exercise and concomitant infections are well-documented cofactors of anaphylaxis in children. Other factors such as consumption of nonsteroidal anti-inflammatory drugs, alcohol ingestion, and stress have been reported. Cofactors reportedly play a role in approximately 30% of anaphylactic reactions in adults and 14%-18.3% in children. Food-dependent exercise-induced anaphylaxis (FDEIA) is the best-studied model of cofactor-induced anaphylaxis. Wheat-dependent exercise-induced anaphylaxis, the most common FDEIA condition, has been studied the most. The mechanisms of action of cofactors have not yet been fully identified. This review aims to educate clinicians on recent developments in the role of cofactors and highlight the importance of recognizing cofactors in food allergies and food-induced anaphylaxis.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.86.2-86.2
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• 2010

In order to improve polymer electrolyte membrane fuel cell (PEMFC) durability, the durability of membrane electrode assemblies (MEA), in which the electrochemical reactions actually occur, is one of the vital issues. Many articles have dealt with catalyst layer degradation of the durability-related factors on MEAs in relation to loss of catalyst surface area caused by agglomeration, dissolution, migration, formation of metal complexes and oxides, and/or instability of the carbon support. Degradation of catalyst layer during long-term operation includes cracking or delamination of the layer which result either from change in the catalyst microstructure or loss of electronic or ionic contact with the active surface, can result in apparent activity loss in the catalyst layer. Membrane degradation of the durability-related factors on MEAs can be caused by mechanical or thermal stress resulting in formation of pinholes and tears and/or by chemical attack of hydrogen peroxide radicals formed during the electrochemical reactions. All of these effects, the mechanical damage of membrane and degradation of catalyst layers are more facilitated by uneven stress or improper MEA fabrication process. In order to improve the PEMFC durability, therefore, it is most important to minimize the uneven stress or improper MEA fabrication process in the course of the fabrication of MEA. We analyzed the effects of the MEA fabrication condition on the PEMFC durability with MEA produced using CCM (catalyst coated membrane) method. This paper also investigated the effects of MEA fabrication condition on the PEMFC durability by adding additional treatment process, hot pressing and pressing, on the MEA produced using CCM method.

• 한국조경학회지
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• 제43권6호
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• pp.127-137
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• 2015

스트레스에 대한 연구결과를 보면 대학생들은 학업과 사회관계 그리고 경제적 의존 등으로 인하여 매우 심각한 스트레스를 받고 있는 것으로 나타난다. 본 연구의 목적은 스트레스 저하이론과 집중력 회복 이론에 근거하여 대학생들의 스트레스와 인지수행에 미치는 자연경관의 영향을 조사하는 것이다. 이를 위해서 피부돌출도(GSR: galvanic skin responsse), 심박시간(IBI: interveat interval), 심리측정(ZIPERS: Zucherman Inventory of Personal Reactions), 그리고 산수암산이 평가도구로 채용되었다. 자연경관의 치유효과는 도시경관과의 비교를 통해 조사되었으며, 128명의 대학생이 연구에 참여하였다. 결과분석에는 120명의 자료가 이용되었다. 연구결과를 보면 심리적 스트레스 해소와 인지향상에서 자연경관의 치유효과가 도시경관보다 더 크게 나타나고 있는데, 이러한 결과는 자연경관의 치유효과를 입증하고 있다. 따라서 자연경관은 학생들의 스트레스 해소와 인지향상에 기여할 것으로 기대된다. 그러나 이러한 효과는 GSR과 IBI를 포함한 두 가지 생리측정에서는 발견되지 않았다. 더 나아가 IBI 측정결과를 보면 도시경관의 치유효과가 자연경관보다 높은 것으로 나타나고 있는데, 이러한 결과는 연구 참여자 특성과 연구대상 경관에 기인하는 것으로 생각된다. 구체적으로 연구 참여자의 나이가 젊고(평균 23.8세), 참여자가 다니는 대학교가 자연경관이 우세한 지역에 있다는 점이 생리측정 결과에 영향을 줄 수 있다. 또한 본 연구에서 사용된 도시경관이 Kaplan and Kaplan이 주장하는 네 가지 치유경관특질 중 하나인 공간감을 갖고 있는 점도 원인으로 생각될 수 있다. 이러한 논의에 근거하면 이후 연구에서는 경관의 내용과 종류 그리고 연구 참여자 특성이 자연경관의 치유효과에 미치는 영향을 밝히는 것이 필요할 것으로 판단된다.

• Journal of Dairy Science and Biotechnology
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• 제38권3호
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• pp.134-141
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• 2020

Oxidative stress is a cascade reaction characterized by a significant increase in the amount of oxidized components. Free radicals produced by oxidative stress are one of the common features in several experimental models of disease, and contribute to wide range of neurodegenerative diseases, including Alzheimer's disease. Iron (II) species can participate in the Fenton, and Fenton-like reactions, to react with hydrogen peroxide and generate hydroxyl radical. As iron accumulation and oxidative stress are associated with the pathological progression of neurodegenerative diseases, iron chelation and antioxidant therapies have become strategies to combat these diseases. Due to the complexity of the redox system in vivo, a multifaceted approach may be an attractive therapeutic strategy. Further investigations are highly expected for the prevention and treatment of neurodegenerative diseases in future.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.81.1-81
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• 2003

Although plants have evolved to possess various defense mechanisms from local biotic and abiotic stressors, most of yield loss is caused by theses stressors. Recent studies have revealed that several different stress responsive reactions are inter-networking. Therefore, the identification and dissection of stress responsive genes is an essential and first step towards understanding of the global defense mechanism in response to various stressors. For this purpose, we applied cDNA microarray analysis, because it has powerful ability to monitor the global gene expression in a specific situation. To date, more than 10,000 non-redundant genes were identified from seven different cDNA libraries and deposited in our EST database (http://plant.pdrs.re.kr/ks200201/pepper.html). For this study, we have built 5K cDNA microarray containing 4,685 unigene clones from three different cDNA libraries. Monitoring of gene expression profiles of hot pepper interactions with biotic stress, abiotic stresses and chemical treatments will be presented. Although this work shows expression profiling at the sub-genomic level, this could be a good starting point to understand the complexity of global defense mechanism in hot pepper.