• Journal of the Earthquake Engineering Society of Korea
• /
• v.24 no.5
• /
• pp.197-209
• /
• 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
• /
• v.4 no.2
• /
• pp.53-58
• /
• 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.

• Korean Security Journal
• /
• no.15
• /
• pp.89-105
• /
• 2008

The aim of this study is to examine the primary causes of security guard's stress by conducting a survey of 50 guards engaging in security companies in Seoul and Gyeonggido. The following results are attained by an inductive content analysis of conviction interview data through in-depth interview of qualitative study method. 1. Factors of stress related to personal problems. The stress by personal problems is resulted from two factors. One is the physical strength inferiority, which leads to negative thoughts, dismay, mental conflict and tension. The other is complex about not-specializing security, which causes discord with his/her supervisor or co-workers and a feeling of uneasiness. 2. Factors of stress related to human relationship. The stress due to human relations is constantly resulted from discord with his/her supervisor and inclined to be accumulated. The mental conflict is elated in feeling that the manager's instructions are not right. So this factor makes them want change of occupation. Also working conditions are different from those of their friends, which causes them not to spend a lot of time with their friends. 3. Factors of stress related to domestic life It appears that most security guards are under stress due to their spouses' discontent with a small number of wages. Also it is reported that male guards are under stress in case of unhappy conjugal relations. And security guard's life is restricted much more than that of workers in a general occupation because of standing ready for mobilization and 24-hour service. So some of male guards experienced an early symptoms of a morbid suspicion about their wife's chastity and are suffering from insomnia as an occupational disease.

• Proceedings of the Korean Society of Plant Biotechnology Conference
• /
• 2002.04a
• /
• pp.41-47
• /
• 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.

• Proceedings of the Korean Society of Plant Biotechnology Conference
• /
• 2002.04b
• /
• pp.41-47
• /
• 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
• /
• v.63 no.5
• /
• pp.607-613
• /
• 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
• /
• v.30 no.6
• /
• pp.755-764
• /
• 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.

• Journal of Life Science
• /
• v.33 no.12
• /
• pp.1062-1073
• /
• 2023

Although depression is a common psychiatric disorder that negatively affects individuals and societies, its exact pathogenesis is not well understood. Stress is a major risk factor for depression and is known to increase susceptibility by triggering inflammation. Indeed, many preclinical and clinical studies have suggested a strong link between depression and inflammation. Depression is associated with increased levels of pro-inflammatory cytokines, such as interleukin (IL-)1β, IL-6, IL-12, tumor necrosis factor-α, and interferon-γ, and decreased levels of the anti-inflammatory IL-4, IL-10, and transforming growth factor-β. Administering pro-inflammatory cytokines causes depression-like behaviors in rodents. Conversely, administering anti-inflammatory drugs appears to ameliorate depressive symptoms. Although the importance of inflammation as a mediator of depression has been demonstrated, the mechanisms by which inflammation is activated in depression remain unclear. To address this issue, recent studies have focused on the importance of stress-induced sterile inflammation. Sterile inflammation refers to the activation of inflammatory processes due to physical and/or psychological stress in the absence of pathogens. Stress promotes the release of endogenous factors known as damage-associated molecular patterns (DAMPs), thereby triggering sterile inflammation. In turn, DAMPs are recognized by pattern recognition receptors, leading to the production of pro-inflammatory cytokines. Here, we review the role of DAMPs in depression based on preclinical and clinical evidence on the dysregulation of sterile inflammation.

• Journal of Plant Biotechnology
• /
• v.44 no.2
• /
• pp.142-148
• /
• 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
• /
• v.49 no.2
• /
• pp.129-135
• /
• 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.