• Title/Summary/Keyword: Stress adaptation

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Experimental Test Numerical Simulation of SMA Characteristics and Device verification (형상기억합금 수치해석을 위한 특성 실험 및 작동기 응용)

  • Kim, Sang-Haun;Choi, Hyun-Ho;Cho, Maeng-Hyo
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2005.11a
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    • pp.145-148
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    • 2005
  • In this study, adaptation of two-way shape memory effect of SMA wire to the actuator is examined . Therefore the SMA characteristics which are training, material properties, response time at different thermal cycling rates are tested. During training, permanent deformation is accumulated till a certain number of cycle and then saturated. The amow1t of two-way strain is unchangeable over all cycle and the slope of strain(or stress)-temperature curve is slower as the increase of applied stress. The rate effect is observed resulted from the thermal distribution which heating profile differs from cooling as thermal cycling time. Using the estimated SMA properties, an experimental test for the simple smart wing is performed.

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The Effects of Hardiness : A Meta-Analysis of Korean Nursing Research Findings (국내 강인성 효과 연구결과에 대한 메타분석)

  • Kim, Young Ock
    • Korean Journal of Adult Nursing
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    • v.17 no.5
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    • pp.783-792
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    • 2005
  • Purpose: This study was conducted to meta-analyze the effects of hardiness on health-related variables. Method: After review of 19 studies performed by Korean nurses, research variables, statistical data(r or F), and other methodological data were extracted and coded. Research variables were categorized under 5 groups such as health-related behavior, well-being, adaptation, stress, and support according to conceptual similarity. Using SAS program, 20 research variables and 34 effect sizes were calculated after eliminating heterogeneous data by Q-test, Results: Effects of hardiness on whole research variables was .512 and ranged from .322 to .643 by categories. The greatest effect was obtained from well-being category, whereas the smallest effect from stress category. All effect sizes were statistically significant. But fail-safe numbers were small and failed to achieve reasonable tolerance level. Conclusion: Results of meta-analysis indicated that hardiness has a moderate effect on health-related variables. But for improving the reliability of the results by minimizing publication bias, the more hardiness studies should be done.

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Global Assessment of Climate Change-Associated Drought Risk

  • Kim, Heey Jin;Kim, Yeonjoo
    • Proceedings of the Korea Water Resources Association Conference
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    • 2019.05a
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    • pp.397-397
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    • 2019
  • With the consequences of climate change becoming more evident, research on climate-associated risks has become a basis for climate adaptation and mitigation. Amongst the different sectors and natural resources considered in assessing such risks, drought is one impact to our environment that experiences stress from climate change but is often overlooked and has the potential to bring severe consequences when drought occurs. For example, when temperatures are higher, water demand increases and water supply decreases; when precipitation patterns fluctuate immensely, floods and droughts occur more frequently at greater magnitudes, putting stress on ecosystems. Hence, it is important for us to evaluate drought risk to observe how different climate change and socioeconomic scenarios can affect this vital life resource. In this study, we review the context of drought risk on the basis of climate change impacts and socioeconomic indicators. As underlined in the IPCC AR5 report, the risks are identified by understanding the vulnerability, exposure, and hazards of drought. This study analyzed drought risk on a global scale with different RCP scenarios projected until the year 2099 with a focus on the variables population, precipitation, water resources, and temperature.

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Music Psychotherapy Program on Acculturative Stress for North Korean Child Defectors (새터민 아동의 문화적응 스트레스 감소를 위한 음악심리치료 적용 연구)

  • Chung, Hyun Chung
    • Journal of Music and Human Behavior
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    • v.6 no.1
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    • pp.1-31
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    • 2009
  • This study aims to conduct a music psychotherapy program on North Korean child defectors, who are experiencing acculturative stress, and to discover the effects of the program on the participants' acculturative stress. This study targeted four North Korean child defectors, who belonged to an H afterschool class in Seoul and performed the program in individual sessions for about 40 minutes per session, totaling 14 sessions. The research results include the following. First, after comparing the results of acculturative stress score that measured before and after the execution of the music psychotherapy program, the mean of the score was significantly decreased from 32.75 to 23 average. Furthermore, as a result of conducting a qualitative analysis of the lingual responses that the participants demonstrated in musical activity, in relation to acculturative stress, the participants were found to experience a positive change. These results imply that the music psychotherapy program offers consistent support through music to North Korean Child Defectors, who are cowering psychologically and experiencing difficulty in adaptation, and reinforces inner resources through their positive self-perception, which indicates that it can be an effective mediation in reducing their acculturative stress.

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Parental inheritance of heat stress tolerance during grain filling period in wheat

  • Ko, Chan Seop;Ou, Meong Kyu;Hyun, Jong Nae;Kim, Kyung Hun;Kim, Jin Baek;Hong, Min Jeong;Seo, Yong Weon
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2017.06a
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    • pp.142-142
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    • 2017
  • Wheat (Triticum asetivum L.) is one of the major grain crops worldwide. The reduced productivity ascribed by adverse environment is increasing the risk of food security. Wheat cultivars have been actively released by public side since 1960s in Korea. Each variety has been developed for superior regional adaptation, pest resistance and mostly high yield. Heat stress tolerance is one of the major parameters that threaten wheat production in Korea. Heat stress during grain filling period has been conceived as critical level and directly influences on wheat production. We evaluated 11 common wheat cultivars ("Baegjoong", "Dajung", "Goso", "Hanbaek", "Jokyoung", "Joeun", "Jopum", "Keumgang", "Olgeuru", "Sinmichal", "Uri") that were exposed to abnormally high temperature during the grain filling period. Each plant was grown well in a pot containing "Sunshine #4" soil in controlled phytotron facility set on $20^{\circ}C$ and 16 h photoperiod. At 9 day-after-anthesis (DAA9), plants were subjected to a gradual increase in temperature from $20^{\circ}C$ to $33^{\circ}C$ and maintained constantly at $33^{\circ}C$ for 5 days. After the treatment, plants were subjected to gradual decrease to normal temperature ($20^{\circ}C$) and continue to grow till harvest. Seeds were harvested from each tiller/plant. Total chlorophyll contents decrease level as well as grain parameters were measured to evaluate varietal tolerance to heat stress. We also divide each spike into five regions and evaluate grain characteristics among the regions in each spike. The obtained results allow us to classify cultivars for heat stress tolerance. The pedigree information showed that typical wheat lines provide either tolerance or susceptible trait to their off-springs, which enable breeders to develop heat stress tolerance wheat by appropriate parental choice.

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Transcriptome-based identification of water-deficit stress responsive genes in the tea plant, Camellia sinensis

  • Tony, Maritim;Samson, Kamunya;Charles, Mwendia;Paul, Mireji;Richard, Muoki;Mark, Wamalwa;Stomeo, Francesca;Sarah, Schaack;Martina, Kyalo;Francis, Wachira
    • Journal of Plant Biotechnology
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    • v.43 no.3
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    • pp.302-310
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    • 2016
  • A study aimed at identifying putative drought responsive genes that confer tolerance to water stress deficit in tea plants was conducted in a 'rain-out shelter' using potted plants. Eighteen months old drought tolerant and susceptible tea cultivars were each separately exposed to water stress or control conditions of 18 or 34% soil moisture content, respectively, for three months. After the treatment period, leaves were harvested from each treatment for isolation of RNA and cDNA synthesis. The cDNA libraries were sequenced on Roche 454 high-throughput pyrosequencing platform to produce 232,853 reads. After quality control, the reads were assembled into 460 long transcripts (contigs). The annotated contigs showed similarity with proteins in the Arabidopsis thaliana proteome. Heat shock proteins (HSP70), superoxide dismutase (SOD), catalase (cat), peroxidase (PoX), calmodulinelike protein (Cam7) and galactinol synthase (Gols4) droughtrelated genes were shown to be regulated differently in tea plants exposed to water stress. HSP70 and SOD were highly expressed in the drought tolerant cultivar relative to the susceptible cultivar under drought conditions. The genes and pathways identified suggest efficient regulation leading to active adaptation as a basal defense response against water stress deficit by tea. The knowledge generated can be further utilized to better understand molecular mechanisms underlying stress tolerance in tea.

Relationship of Locus of Control, Difficulties in Emotion Regulation, and Clinical Practice Stress (간호대학생들의 내·외통제소재, 정서조절곤란 및 임상실습스트레스의 관계)

  • Choi, Yeon-Sook;Lee, Eunju;Lee, Dohyeon
    • The Journal of the Korea Contents Association
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    • v.18 no.1
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    • pp.540-550
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    • 2018
  • The purpose of this study was to investigate the relationship of internal-external control, difficulties in emotion regulation, and clinical practice stress among college nursing students. The study was conducted, based on a sample of 220 students at one college and the data were analyzed using descriptive statistics, t-test, ANOVA, Pearson correlation coefficient and stepwise regression analysis. As a result of correlation analysis, there were significant positive correlation in difficulty of emotion regulation score and clinical practice stress score according to external control score. Factors affecting on clinical practice stress were locus of control, difficulties in emotion regulation, college satisfaction, grade, and religion having explanation rate of 17%. Therefore, to decrease clinical stress among nursing students, Nursing students should be considered the emotion regulation with external control disposition. The results can contribute as a basic data in developing education strategies and clinical adjustment programs for regulating clinical stress with emotion management and adaptation on clinical environment.

Relationship between Acculturative Stress and Mental Health of Multicultural Youths - Focused on the Mediating Effect of Social Support - (다문화 청소년의 문화적응 스트레스와 정신건강의 관계 -사회적 지지 매개 효과 중심으로-)

  • Jang, Seon-Ah;Go, Jeonghun
    • The Journal of the Korea Contents Association
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    • v.21 no.1
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    • pp.662-673
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    • 2021
  • This study is to investigate the mediating effects of social support on the relationship between acculturative stress and mental health of multicultural youth. The results of the study were as follows: 1.573 of the 4th(middle 1) to 6th(middle 3) of the multicultural youth panel were analyzed by AMOS 22.0. First, the acculturation stress of multicultural youths had a positive effect on mental health. Second, acculturation stress of multicultural youths had a negative effect on social support. Third, social support of multicultural youths had a negative effect on mental health. Fourth, social support of multicultural youths had a mediating effect on the effect of acculturation stress on mental health. This result shows that the stress of multicultural youths in the process of adapting to the dual culture negatively affects social support, and this social support has a positive effect on the mental health of multicultural youths.

Analysis of the Change of Amino Acids by Abscisic acid and Polyamine Treatment in Radish Young Cotyledons (무우 유식물의 자엽에서 Abscisic acid와 Polyamine 처리에 의한 아미노산 변화의 분석)

  • Cho, Bong-Heuy
    • Analytical Science and Technology
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    • v.12 no.5
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    • pp.441-446
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    • 1999
  • The changes of amino acids in the cotyledons of spring - and winter radishes were analysed during the abscisic acid (ABA). ABA plus cycloheximide (CH) and ABA plus polyamine (PA) treatment. The total contents of amino acids were increased in spring radishes, and decreased in winter radishes by ABA. The contents of hydrophilic amino acids, proline, glycine, serine and cysteine in spring radishes (expecially proline), and of cysteine, leucine and phenylalanine in winter radishes (expecially cysteine and leucine)were increased, CH treatment resulted in the accumulation of amino acids by the inhibition of new synthesized protein, which synthesized against ABA induced dehydration both of radishes. On the contrary, the contents of amino acids were decreased in spring radishes, and increased in winter radishes during PA treatment. These results indicated that the accumulated hydrophilic amino acids and new synthesized proteins induced the adaptation of dehydration against stress and the role of ABA in accelerating of stress adaptation was mediated by polyamines.

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Isolation and Characterization of Bifidobacterium longum subsp. longum BCBR-583 for Probiotic Applications in Fermented Foods

  • Yi, Da Hye;Kim, You-Tae;Kim, Chul-Hong;Shin, Young-Sup;Lee, Ju-Hoon
    • Journal of Microbiology and Biotechnology
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    • v.28 no.11
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    • pp.1846-1849
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    • 2018
  • Recent human gut microbiome studies have supported that the genus Bifidobacterium is one of the most beneficial bacteria for human intestinal health. To develop a new probiotic strain for functional food applications, fourteen fecal samples were collected from healthy Koreans and the strain BCBR-583 was newly selected and isolated from a 25-year-old Korean woman's fecal sample using the selective medium for Bifidobacterium. Subsequent fructose-6-phosphate phosphoketolase (F6PPK) test and 16S rRNA gene sequencing analysis of the strain BCBR-583 confirmed that it belongs to B. longum subsp. longum. The stress resistance tests showed that it has oxygen and heat tolerance activities (5- and 3.9-fold increase for 24 h at 60 and 120 rpm, respectively; $78.61{\pm}6.67%$ survival rate at $45^{\circ}C$ for 24 h). In addition, gut environment adaptation tests revealed that this strain may be well-adapted in the gut habitat, with gastric acid/bile salt resistance ($85.79{\pm}1.53%$, survival rate under 6 h treatments of gastric acid and bile salt) and mucin adhesion ($73.72{\pm}7.36%$). Furthermore, additional tests including cholesterol lowering assay showed that it can reduce $86.31{\pm}1.85%$ of cholesterol. Based on these results, B. longum BCBR-583 has various stress resistance for survival during food processing and environmental adaptation activities for dominant survival in the gut, suggesting that it could be a good candidate for fermented food applications as a new probiotic strain.