• Title/Summary/Keyword: Stressors

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Entomopathogenic Fungi-mediated Pest Management and R&D Strategy (곤충병원성 진균을 활용한 해충 관리와 개발 전략)

  • Lee, Se Jin;Shin, Tae Young;Kim, Jong-Cheol;Kim, Jae Su
    • Korean journal of applied entomology
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    • v.61 no.1
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    • pp.197-210
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    • 2022
  • Entomopathogenic fungi can be used to control a variety of sucking and chewing insects, with little effect on beneficial insects and natural enemies. Approximately 170 entomopathogenic fungal insecticides have been registered and used worldwide, with the recent focus being on the mode of action and mechanism of insect-fungal interactions. During the initial period of research and development, the industrialization of entomopathogenic fungi focused on the selection of strains with high virulence. However, improvement in productivity, including securing resistance to environmental stressors, is a major issue that needs to be solved. Although conidia are the primary application propagules, efforts are being made to overcome the limitations of blastospores to improve the economic feasibility of the production procedure. Fungal transformation is also being conducted to enhance insecticidal activity, and molecular biology is being used to investigate functions of various genes. In the fungi-based pest management market, global companies are setting up cooperative platforms with specialized biological companies in the form of M&As or partnerships with the aim of implementing a tank-mix strategy by combining chemical pesticides and entomopathogenic fungi. In this regard, understanding insect ecology in the field helps in providing more effective fungal applications in pest management, which can be used complementary to chemicals. In the future, when fungal applications are combined with digital farming technology, above-ground applications to control leaf-dwelling pests will be more effective. Therefore, for practical industrialization, it is necessary to secure clear research data on intellectual property rights.

Antidepressant-like effects of Nelumbo nucifera leaves extract in chronic mild stress model (만성스트레스 모델에서 하엽추출물의 항우울 효과)

  • Kang, Min Gu;Kim, Young Hwa;Im, A Rang;Nam, Byung Soo;Chae, Sung Wook;Lee, Mi Young
    • The Korea Journal of Herbology
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    • v.29 no.2
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    • pp.7-13
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    • 2014
  • Objectives : Chronic mild stress (CMS) model is currently recognized as a better animal model of depression. The purpose of this study was to investigate the antidepressant-like effects of the Nelumbo nucifera leave extract using CMS model. Methods : The antidepressant-like effects of Nelumbo nucifera leaves extract was determined by using animal models of depression. Male ICR mice were divided into four groups: saline-treated normal, without CMS; saline-treated stress control; CMS+ Imipramine(20mg/kg); CMS+Nelumbo nucifera leaves extract(200mg/kg). All mice except the normal group exposed an unpredicted sequence of chronic mild stressors for 5 weeks. The behavior of mice were detected by sucrose preference test, forced swim test and tail suspension test. Then concentration of corticosterone in serum was detected by enzyme immunoassay. Results : Nelumbo nucifera leaves extract administration by daily gavage from the 3rd week exhibited an antidepressant-like effect on CMS-induced depression in mice. Nelumbo nucifera leaves extract administration at dose of 200 mg/kg significantly increased the sucrose consumption, and decreased the immobility durations in forced swim test and tail suspension test. Furthermore the corticosterone level decreased than control group. Conclusions : Chronic mild stress can affect mouse behavior and corticosterone level and cause depression. The present experiments not only further confirm the antidepressant-like effects of Nelumbo nucifera leaves extract in the sucrose preference test, forced swimming test and tail suspension test, but also the improving effects of Nelumbo nucifera leaves extract on the depression-like symptoms in the CMS model. Nelumbo nucifera leaves extract has the antagonism on CMS and produce antidepressive effects.

A study on the parenting stress factors and the copying strategies of marriage immigrant women raising middle and high school student (중·고등학생 자녀를 양육하는 결혼이주여성의 양육스트레스와 대처방안에 대한 연구)

  • Huang, Haiying;Lee, Mijung
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.5 no.4
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    • pp.415-426
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    • 2015
  • This study is intended to learn about the factors appearing in parenting stress and the copying strategies by targeting marriage immigrant women who are raising middle and high school student. To this end, in-depth interviews were conducted on seven participants of Marriage Migrant Women who are living in Seoul and Gyeongi area. Generally to say, first of results showed that the personal factors, family factors, social factors and enculturative factors were found out as the factors of parenting stress of them. Secondly, problem-centered and emotion-focused coping strategies for the factors of stress were the main ways. Specifically, as the individual factors, the self-efficiency was coped with problem-focused ways and the parenting roles were coped with emotion-focused ways. As the family factors, child's activity and sociality impact their school adjustment and their mother's parenting stress and, various copying strategies were used depending on the different situation. For the social factors, looking for family supporting as the active problem-focused coping ways were used in husband's family and looking for emotional comfort as the emotion-focused coping ways were used in parents' home. In the case of enculturative factors, the emotion-focused coping strategies were used for the Public gaze and the prejudice around them that caused overwhelming sense of helplessness.

Life-Cycle Cost Effective Optimal Seismic Retrofit and Maintenance Strategy of Bridge Structures - (I) Development of Lifetime Seismic Reliability Analysis S/W (교량의 생애주기비용 효율적인 최적 내진보강과 유지관리전략 - (I) 생애주기 지진신뢰성해석 프로그램 개발)

  • Lee, Kwang-Min;Choi, Eun-Soo;Cho, Hyo-Nam;An, Hyoung-Jun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.6A
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    • pp.965-976
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    • 2006
  • A realistic lifetime seismic-reliability based approach is unavoidable to perform Life-Cycle Cost (LCC)-effective optimum design, maintenance, and retrofitting of structures against seismic risk. So far, though a number of researchers have proposed the LCC-based seismic design and retrofitting methodologies, most researchers have only focused on the methodological point. Accordingly, in most works, they have not been quantitatively considered critical factors such as the effects of seismic retrofit, maintenance, and environmental stressors on lifetime seismic reliability assessment of deteriorating structures. Thus, in this study, a systemic lifetime seismic reliability analysis methodology is proposed and a program HPYER-DRAIN2DX-DS is developed to perform the desired lifetime seismic reliability analysis. To demonstrate the applicability of the program, it is applied to an example bridge with or without seismic retrofit and maintenance strategies. From the numerical investigation, it may be positively stated that HYPER-DRAIN2DX-DS can be utilized as a useful numerical tool for LCC-effective optimum seismic design, maintenance, and retrofitting of bridges.

Lifetime Reliability Based Life-Cycle Cost-Effective Optimum Design of Steel Bridges (생애 신뢰성에 기초한 강교의 LCC최적설계)

  • Lee, Kwang Min;Cho, Hyo Nam;Cha, CheolJun;Kim, Seong Hun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.1A
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    • pp.75-89
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    • 2006
  • This paper presents a practical and realistic Life-Cycle Cost (LCC) optimum design methodology of steel bridges considering time effect of bridge reliability under environmental stressors such as corrosion and heavy truck traffics. The LCC functions considered in the LCC optimization consist of initial cost, expected life-cycle maintenance cost and expected life-cycle rehabilitation costs including repair/replacement costs, loss of contents or fatality and injury losses, road user costs, and indirect socio-economic losses. For the assessment of the life-cycle rehabilitation costs, the annual probability of failure which depends upon the prior and updated load and resistance histories should be accounted for. For the purpose, Nowak live load model and a modified corrosion propagation model considering corrosion initiation, corrosion rate, and repainting effect are adopted in this study. The proposed methodology is applied to the LCC optimum design problem of an actual steel box girder bridge with 3 continuous spans (40 m+50 m+40 m=130 m), and various sensitivity analyses of types of steel, local corrosion environments, average daily traffic volume, and discount rates are performed to investigate the effects of various design parameters and conditions on the LCC-effectiveness. From the numerical investigation, it has been observed that local corrosion environments and the number of truck traffics significantly influence the LCC-effective optimum design of steel bridges, and thus realized that these conditions should be considered as crucial parameters for the optimum LCC-effective design.

A Study on Antecedents of Suicidal Ideation among Korean Older Adults: A test of the Stress-diathesis Model (노인의 자살 생각에 영향을 미치는 선행요인에 관한 연구: 스트레스 소질 모델(Stress-diathesis Model)을 중심으로)

  • Ahn, Joonhee;Chun, Miae
    • 한국노년학
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    • v.29 no.2
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    • pp.489-511
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    • 2009
  • While late-life suicide has been increasing and become an important issue for public health in Korea, little is known about the phenomenon and its contributing risk factors based on which effective preventive measures can be made. Since suicidal ideation is a major precursor to attempted and completed suicide, the objective of the present study was to reveal primary contributors to suicidal ideation. Data were collected from a cross-sectional survey of 247 community-dwelling Korean older adults (age≥60) in the mid-size city in Korea. The statistical methodology employed a robust hierarchical regression procedure that iteratively downweights outliers. Based on the stress-diathesis model, the study examined major diathesis and stressors directly explaining suicidal ideation. The study also explored the significant interaction among these factors. The findings revealed that living alone and depression were significant main antecedents of suicidal ideation. In addition, neuroticism X life events and neuroticism X depression were significant interaction terms with the strongest explanatory power, which provides an empirical evidence to support the stress-diathesis model in explaining suicidal phenomenon of the Korean elderly. The result demonstrates the theoretical implication as well as the practical implication for developing and implementing late-life suicide prevention strategies. Limitations and directions for future research are discussed.

Production and Spatiotemporal Analysis of High-Resolution Temperature-Humidity Index and Heat Stress Days Distribution (고해상도 온습도지수 및 고온 스트레스 일수 분포도의 제작과 이를 활용한 시공간적 변화 분석)

  • Dae Gyoon Kang;Dae-Jun Kim;Jin-Hee Kim;Eun-Jeong Yun;Eun-Hye Ban;Yong Seok Kim;Sera Jo
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.25 no.4
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    • pp.446-454
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    • 2023
  • The impact of climate change on agriculture is substantial, especially as global warming is projected to lead to varying temperature and humidity patterns in the future. These changes pose a higher risk for both crops and livestock, exposing them to environmental stressors under altered climatic conditions. Specifically, as temperatures are expected to rise, the risk of heat stress is assessable through the Temperature-Humidity Index (THI), derived from temperature and relative humidity data. This study involved the comparison of THI collected from 10 Korea Meteorological Administration ASOS stations spanning a 60-year period from 1961 to 2020. Moreover, high-resolution temperature and humidity distribution data from 1981 to 2020 were employed to generate high-resolution TH I distributions, analyzing temporal changes. Additionally, the number of days characterized by heat stress, derived from TH I, was compared over different time periods. Generally, TH I showed an upward trend over the past, albeit with varying rates across different locations. As TH I increased, the frequency of heat stress days also rose, indicating potential future cost increases in the livestock industry due to heat-related challenges. The findings emphasize the feasibility of evaluating heat stress risk in livestock using THI and underscore the need for research analyzing THI under future climate change scenarios.

Mental Representation for Family in Abused Children: Focusing on Types of Child Abuse (피학대 아동의 가족에 대한 정신적 표상: 성, 연령 및 학대유형별 비교를 중심으로)

  • Kyung-Sook Lee;Jin-Ah Park;Eun Jeong Oh
    • Korean Journal of Culture and Social Issue
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    • v.14 no.3
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    • pp.1-19
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    • 2008
  • The purpose of this study is to examine the family perception according to abused children's sex, age, and abusive type. The subjects were 45 abused children including 15 physically abused, 15 neglected, and 15 physically and emotionally abused children from age 7 to 14. The results were that boys showed more noncomplient behaviors to their parents, more concerns and more rejective behaviors to examination. Girls perceived their mothers as stressors more than those of boys. School-aged children perceived their mothers as allies than those of adolescents. Adolescents showed more rejective behaviors to examination and more anger. Physically and emotionally abused children experienced more family conflicts and showed more negative resolutions, and more noncomplient behaviors than those of abused children. Neglected children showed more depressive mood than those of abused children.

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Evaluation and Management of Frailty, and Its Association With Pain (노쇠의 평가와 관리, 그리고 통증과의 연관성)

  • Kang Joon Lee
    • Korean Journal of Psychosomatic Medicine
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    • v.32 no.1
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    • pp.1-9
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    • 2024
  • Frailty is a clinical syndrome as an increased vulnerability to stressors, leading to a decrease in physiologic reserves and a decline in the ability to maintain a good homeostasis. This condition leads to an increased risk of hospitalization, disability and mortality. Frailty occurs due to various causes and requires a multidimensional approach. It is also important to detect and manage it early. Frailty is also deeply related to neuropsychiatric problems such as pain and depression. In evaluating frailty, it is desirable to comprehensively consider not only physical areas such as disease, nutrition, movement, and sensory functions, but also psychosocial areas, and representative scales include Fried's physical frailty phenotype and Rockwood's frailty index. Physical activity and appropriate protein intake are important for frailty management, and inappropriate drug use should be reduced and oral care, cognitive function, and falls should also be noted. Frailty and pain can affect each other, and pain can promote frailty. Evidence has been published that hormone and protein abnormalities, immune system activity and inflammatory response, and epigenetic mechanisms work in common in the field of frailty and pain. More extensive and high-quality research should be conducted in the future, and the quality of life will be improved if the results are applied to the suppression and treatment of old age and pain.

Study on the Efficacy of Paeonia Japonica, Cucurbita Moschata and Prunus Cerasus Complex Extract for Alleviating Stress Associated with Chronic Skin Conditions (만성 피부 질환으로 발생하는 스트레스 개선을 위한 호박, 작약, 타트체리 복합물의 효능 연구)

  • Su-Jin Park;Dong-Hee Kim;Ki-Sung Kwak;Hyun-Jeong Kim
    • Journal of the Korean Applied Science and Technology
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    • v.41 no.2
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    • pp.459-471
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    • 2024
  • In modern society, where tension and stress are ubiquitous, individuals often experience psychological imbalances. These stressors not only affect mental well-being but also manifest physically, through the skin. Consequently, a new term psychodermatology combining psychiatry and dermatology, has emerged, garnerning attention and research focus. In this study, we aimed to develop materials improving chronic skin conditions caused by stress by utilizing a compound of Cucurbita moschata, Paeonia japonica, and Prunus cerasus known to alleviate skin disorders. We sought to develop and validate the efficacy of materials alleviating chronic skin conditions induced by stress in keratinocytes..Therefore, in this study we analyzed the effects of a complex extract using Cucurbita moschata, Paeonia japonica, and Prunus cerasus on HaCaT keratinocyte cells to understand how it influences them. The complex extract on HaCaT keratinocyte cells showed a concentration-dependent decrease in the expression levels of TNF-α, IL-1β, IL-6, MDC, and TARC at concentrations of 12.5, 25, 50 and 100 ㎍/mL. Particularly noteworthy was the efficacy observed in inhibiting IL-1β, with a reduction of over 40% at a concentration of 100 ㎍/mL. Additionally, the production levels of AQP-3, HA, and filaggrin exhibited a significant concentration-dependent increase. The protein expression of p-ERK, p-JNK, and p-p38, which were elevated by TNF-α/IFN-γ, was significantly decreased with the treatment of the complex extract. These findings suggest that the compound extract may be utilized as a material for treating and preventing skin conditions, potentially mitigating the adverse effects of the mutual relationship between skin disorders and stress.