• 한국지진공학회논문집
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• 제24권5호
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• pp.197-209
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• 2020

Evidence of liquefaction during the 2017 Pohang earthquake has highlighted the urgent need to evaluate the current seismic design standard for liquefaction in Korea, particularly the liquefaction triggering standard. With the simplified method, which is the most popular method for evaluating liquefaction triggering, the factor of safety for liquefaction triggering is calculated via the cyclic stress ratio (CSR) and the cyclic resistance ratio (CRR). The parameters in the CSR and CRR have undergone changes over time based on new research findings and lessons learned from liquefaction case-histories. Hence, the current design standard for liquefaction triggering evaluation in Korea should also reflect these changes to achieve seismic safety during future earthquakes. In this study, liquefaction susceptibility criteria were discussed initially and this was followed by a review of the current liquefaction triggering codes/guidelines in other countries and Korea. Next, the parameters associated with the CSR such as the maximum ground acceleration, stress reduction factor, magnitude scaling factor, and overburden correction factor were discussed in detail. Then, the evaluation of the CRR using the SPT N-value and CPT qc-value was elaborated along with overburden and clean-sand correction factors. Based on this review of liquefaction triggering evaluation standards, recommendations are made for improving the current seismic design standard related to liquefaction triggering in Korea.

• Journal of Plant Biotechnology
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• 제4권2호
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• pp.53-58
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• 2002

Adverse environmental conditions such as drought, high salt and cold/freezing are major factors that reduces crop productivity worldwide. According to a survey, 50-80% of the maximum potential yield is lost by these "environmental or abiotic stresses", which is approximately ten times higher than the loss by biotic stresses. Thus, improving stress-tolerance of crop plants is an important way to improve agricultural productivity, In order to develop such stress-tolerant crop plants, we set out to identify key stress signaling components that can be used to develop commercially viable crop varieties with enhanced stress tolerance. Our primary focus so far has been on the identification of transcription factors that regulate stress responsive gene expression, especially those involved in ABA-mediated stress response. Be sessile, plants have the unique capability to adapt themselves to the abiotic stresses. This adaptive capability is largely dependent on the plant hormone abscisic acid (ABA), whose level increases under various stress conditions, triggering adaptive response. Central to the response is ABA-regulated gene expression, which ultimately leads to physiological changes at the whole plant level. Thus, once identified, it would be possible to enhance stress tolerance of crop plants by manipulating the expression of the factors that mediate ABA-dependent stress response. Here, we present our work on the isolation and functional characterization of the transcription factors.n factors.

• 시큐리티연구
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• 제15호
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• pp.89-105
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• 2008

본 연구는 서울과 경기도에 소재하고 있는 경호경비회사 경호원 50명을 대상으로 목적적 표집을 하여 질적연구 방법인 심층면담을 실시하였으며, 경호원들의 스트레스에 대한 면담자료를 귀납적 내용분석(inductive content analysis)을 하여 다음과 같은 결론을 얻었다. 1. 개인적 문제에 의한 스트레스요인 신체조건 불만요인 중 타경호원과 비교 시 체력의 열세로 인한 부정적 생각이 매우 높게 나타났으며, 학력 및 전공불만요인에서도 경호전공자가 아니기 때문에 동료직원이나 상사로부터 느끼는 부조화로 인한 불안감 등으로 정신적 스트레스가 노출되어 있음이 나타났다. 2. 인간관계 문제에 의한 스트레스요인 업무지시에 대한 부정적 생각과 장래문제로 타 직종으로 전직을 하고 싶다는 희망자가 높게 나타났으며, 친구문제에서는 근무조건이 친구들과 맞지 않아 자주 어울리지 못하는 경우와 그로 인한 애인과의 잦은 다툼과 헤어짐으로 마음의 상처를 받는 것으로 나타났다. 3. 가정생활 문제에 의한 스트레스요인 적은 급여에 대한 배후자의 불만으로 대부분의 경호원들이 스트레스를 받고 있는 것으로 나타났다. 특히 경호원을 대상으로 스트레스를 연구한 선행연구에서 보고 되지 않았던 성문제가 스트레스의 근원으로 나타났다는 것에 주목을 끌고 있다. 경호원들이 만족한 부부관계가 안될시 스트레스를 받는다고 답하고 있고, $20{\sim}30$대 경호원들이 24시간 근무로 인한 야간근무를 할 시 배후자를 의심하는 초기 의처증 증세까지 경험한 것으로 나타났다.

• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2002년도 추계학술대회
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• pp.41-47
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• 2002

Adverse environmental conditions such as drought, high salt and cold/freezing are major factors that reduces crop productivity worldwide. According to a survey, $50-80\%$ of the maximum potential yield is lost by these 'environmental or abiotic stresses', which is approximately ten times higher than the loss by biotic stresses. Thus, Improving stress-tolerance of crop plants is an important way to improve agricultural productivity. In order to develop such stress-tolerant crop plants, we set out to identify key stress signaling components that can be used to develop commercially viable crop varieties with enhanced stress tolerance. Our primary focus so far has been on the identification of transcription factors that regulate stress responsive gene expression, especially those involved in ABA-mediated stress response. Be sessile, plants have the unique capability to adapt themselves to the abiotic stresses. This adaptive capability is largely dependent on the plant hormone abscisic acid (ABA), whose level increases under various stress conditions, triggering adaptive response. Central to the response is ABA-regulated gene expression, which ultimately leads to physiological changes at the whole plant level. Thus, once identified, it would be possible to enhance stress tolerance of crop plants by manipulating the expression of the factors that mediate ABA-dependent stress response. Here, we present our work on the isolation and functional characterization of the transcription factors.

• 한국식물생명공학회:학술대회논문집
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• 한국식물생명공학회 2002년도 춘계학술대회
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• pp.41-47
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• 2002

Adverse environmental conditions such as drought, high salt and cold/freezing are major factors that reduces crop productivity worldwide. According to a survey, 50-80% of the maximum potential yield is lost by these 'environmental or abiotic stresses', which is approximately ten times higher than the loss by biotic stresses. Thus, improving stress-tolerance of crop plants is an important way to improve agricultural productivity. In order to develop such stress-tolerant crop plants, we set out to identify key stress signaling components that can be used to develop commercially viable crop varieties with enhanced stress tolerance. Our primary focus so far has been on the identification of transcription factors that regulate stress responsive gene expression, especially those involved in ABA-mediated stress response. Be sessile, plants have the unique capability to adapt themselves to the abiotic stresses. This adaptive capability is largely dependent on the plant hormone abscisic acid (ABA), whose level increases under various stress conditions, triggering adaptive response. Central to the response is ABA-regulated gene expression, which ultimately leads to physiological changes at the whole plant level. Thus, once identified, it would be possible to enhance stress tolerance of crop plants by manipulating the expression of the factors that mediate ABA-dependent stress response. Here, we present our work on the isolation and functional characterization of the transcription factors.

• Journal of Korean Neurosurgical Society
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• 제63권5호
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• pp.607-613
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• 2020

Objective : Spontaneous intracranial hemorrhage is a life-threatening disease, and non-lesional spontaneous intraparenchymal hemorrhage (nIPH) and aneurysmal subarachnoid hemorrhage (aSAH) are the leading causes of spontaneous intracranial hemorrhage. Only a few studies have assessed the association between prior physical activity or triggering events and the occurrence of nIPH or aSAH. The purpose of this study is to investigate the role of specific physical activities and triggering events in the occurrence of nIPH and aSAH. Methods : We retrospectively reviewed 824 consecutive patients with spontaneous intracranial hemorrhage between January 2010 and December 2018. Among the 824 patients, 132 patients were excluded due to insufficient clinical data and other etiologies of spontaneous intracranial hemorrhage. The medical records of 692 patients were reviewed, and the following parameters were assessed : age, sex, history of hypertension, smoking, history of stroke, use of antiplatelet or anticoagulation agents, season and time of onset, physical activities performed according to the metabolic equivalents, and triggering event at onset. Events that suddenly raised the blood pressure such as sudden postural changes, defecation or urination, sexual intercourse, unexpected emotional stress, sauna bath, and medical examination were defined as triggering events. These clinical data were compared between the nIPH and aSAH groups. Results : Both nIPH and aSAH most commonly occurred during non-strenuous physical activity, and there was no significant difference between the two groups (p=0.524). Thirty-two patients (6.6%) in the nIPH group and 39 patients (8.1%) in the aSAH group experienced triggering events at onset, and there was a significant difference between the two groups (p=0.034). The most common triggering events were defecation or urination in both groups. Conclusion : Specific physical activity dose no affect the incidence of nIPH and aSAH. The relationship between the occurrence of intracranial hemorrhage and triggering events is higher in aSAH than nIPH.

• Asian-Australasian Journal of Animal Sciences
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• 제30권6호
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• pp.755-764
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• 2017

The current review seeks to highlight the concerns that have been raised on pre-slaughter stress, contributing factors and its consequent effects on cattle behavioural responses and the quality of beef; inter-linking the activities involved from birth to slaughter. Such information is crucial in light of the consumer concerns on overall animal welfare, quality of meat and food security. Slaughter animals are exposed to different conditions during production and transportation to abattoirs on a daily basis. However; the majority of studies that have been done previously singled out different environments in the meat production chain, while conclusions have been made that the welfare of slaughter animals and the quality of meat harvested from them is dependent on the whole chain. Behaviour is a critical component used to evaluate the animals' wellbeing and it has been reported to have an effect on product quality. Apart from the influence of on-farm, transportation and abattoir conditions, the genetic background of the animal also affects how it perceives and responds to certain encounters. Stress activates the animals' hypothalamic-pituitary-adrenal activity, triggering release of various stress hormones such as catecholamines and cortisol, thus glycogen depletion prior slaughter, elevated ultimate pH and poor muscle-meat conversion. Pre-slaughter stress sometimes results to cattle attaining bruises, resulting to the affected parts of the carcass being trimmed and condemned for human consumption, downgrading of the carcass and thus profit losses.

• 생명과학회지
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• 제33권12호
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• pp.1062-1073
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• 2023

우울증은 개인과 사회에 부정적인 영향을 미치는 흔한 정신질환이지만 그 원인은 아직 명확히 밝혀져 있지 않다. 스트레스는 우울증의 주요 위험인자이며, 염증을 유발하여 우울증에 대한 취약성을 증가시키는 것으로 알려져 있다. 수많은 연구는 우울증과 염증의 강한 연관성을 제안하고 있다. 우울증 환자 혈액에서는 IL-1β, IL-6, IL-12, TNF-α 및 IFN-γ와 같은 친염증성 사이토카인이 증가하였으며, IL-4, IL-10 및 TGF-β와 같은 항염증성 사이토카인이 감소하였다. 설치류에 친염증성 사이토카인을 투여하면 우울 유사 행동이 관찰되는 반면, 항염증제를 투여하면 우울 증상이 완화된다. 이러한 연구들은 우울증의 병인에 염증의 중요성을 강조하고 있다. 우울증에서 염증이 활성화되는 기전에 관한 다양한 연구들이 진행되고 있다. 최근 연구에서는 스트레스로 유발되는 무균 염증의 중요성을 밝히고 있다. 병원균의 감염이 없는 상태에서 신체 및 심리적 스트레스로 인해 염증 과정이 활성화되는 것을 무균 염증이라 한다. 스트레스는 무균 염증을 활성화하기 위해 DAMPs (damage-associated molecular patterns)로 알려진 내인성 인자의 방출을 촉진시키며, 방출된 DAMPs는 해당 수용체인 PRRs (pattern recognition receptors)에 결합함으로서 신호전달을 통해 친염증성 사이토카인 생성을 증가시킨다. 본 종설에서 무균 염증의 조절 장애에 대한 전임상 및 임상 증거를 바탕으로 우울증에서 DAMP의 역할을 검토하고자 한다.

• Journal of Plant Biotechnology
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• 제44권2호
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• pp.142-148
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• 2017

Drought stress is one of the important factors that restrict the expansion of Hevea brasiliensis cultivation to non-traditional regions experiencing extreme weather conditions. Plants respond to drought stress by triggering expression of several drought responsive genes including transcription factors which in turn trigger expression of various downstream signalling pathways and adaptive networks. Expression of such drought responsive genes may revert back to their original level upon re-watering. However, no reports are available on such phenomenon in Hevea and hence, this study was initiated. For this purpose, NAC transcription factor (NAC tf) was chosen as candidate gene. Its expression levels were monitored under intermittent drought as well as irrigated conditions in two clones (RRII 105 and RRIM 600) of H. brasiliensis with contrasting tolerance level. Copy number of NAC tf was found similar in both the clones. Expression of NAC tf was found highly up-regulated in RRIM 600 (a relatively drought tolerant clone) than in RRII 105 (a relatively drought susceptible clone) throughout the drought incidences which upon re-watering, reached back to its original levels in both the clones. The study indicated the existence of an association between expression of NAC tf and drought tolerance trait exhibited by the tolerant clone RRIM 600. The study also proves the influence of drought and re-watering on the leaf photosynthesis and expression of NAC tf in H. brasiliensis.

• Clinical and Experimental Pediatrics
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• 제49권2호
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• pp.129-135
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• 2006

Chronic recurrent abdominal pain is a common manifestation in children. Functional abdominal pain is the most common cause of chronic abdominal pain and can be diagnosed properly by the physician without the requirement of specific evaluation when there are no alarm symptoms or signs. Functional abdominal pain is categorized as functional dyspepsia, irritable bowel syndrome, functional abdominal pain, abdominal migraine, and aerophagia, according to the Rome II criteria for pediatric functional gastrointestinal disorders. New concepts on the pathogenesis of functional abdominal pain include brain-gut interaction, visceral hypersensitivity, gastrointestinal dysmotility, inflammation, autonomic dysfunction, genetic predisposition, and triggering factors including psycho-social stress.