• 제목/요약/키워드: life stresses

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Development and Validation of the Korean Version of the Immigrant Parental Stress Inventory (한국판 이주자 부모 스트레스 척도 개발과 타당화 연구)

  • Yoo, Sun-Young
    • Journal of Family Resource Management and Policy Review
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    • v.19 no.1
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    • pp.1-21
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    • 2015
  • Unlike daily hassles or minor stressors, immigration is an intense life event that may cause excessive stress. In particular, immigrant parents find themselves in a more stressful situation in that they experience stresses caused by immigration and stresses caused by parenting at the same time. The purpose of this study is to develop and validate an Immigrant Parental Stress Inventory (IPSI), that objectively and comprehensively assesses the stress experienced by immigrant parents within the Korean context. Based on the Immigrant Parental Stress Inventory developed within the American context, preliminary items were refined through a literature review and the discussions of experts and immigrant parents and were empirically validated with a sample of 203 immigrant parents residing in Korea. Through exploratory and confirmatory factor analysis, six main factors were identified (Factor1 Difficulties in communication, Factor2 Financial difficulties, Factor3 Difficulties in social adjustment, Factor4 Social discrimination, Factor5 Lack of social resources, Factor6 Difficulties in parenting). The IPSI was shown to be a psychometrically sound instrument that is capable of measuring immigrant parental stress within the Korean context. Social service professionals and researchers studying or working with immigrant families could use the IPSI to examine immigrant parental stress.

An Experimental Study on the Characteristics of Residual Stresses in Welds of SM570-TMC Steels (SM570-TMC 강의 잔류응력 특징에 관한 실험적 연구)

  • Park, Hyeon-Chan;Lee, Jin-Hyeong;Kim, Jae-Hwan;Choe, Ui-Hong;Choe, Myeong-Gi;Jang, Gyeong-Ho
    • Proceedings of the KWS Conference
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    • 2005.06a
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    • pp.276-278
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    • 2005
  • Bridge constructed recently is preferred to have a long span and a simple structure detail considering not only functions as bridge but scenic beauty, maintenance, construction term and life cycle cost, etc. Therefore, it demands a high quality steel like a thick plate steel and a high performance steel. A TMCP steel produced by theme-mechanical control process is now spotlighted due to the weldability for less carbon equivalent. It improved at strength and toughness in microstructure. Resently the SM570-TMC steel, a high strength TMCP steel whose tensile strength is 600MPa, is developed and applied to steel structures. But, for the application of this steel to steel structures, it is necessary to elucidate not only the material characteristics but also the mechanical characteristic of welded joint. In this paper, we investigated the characteristics of residual stresses generated by welding of SM570-TMC steels through an experimental study

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Reliability of Maintained Hull Girders of Two Bulk Carrier Designs Subjected to Fatigue and Corrosion

  • Soares, C.Guedes;Garbatov, Y.
    • Journal of Ship and Ocean Technology
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    • v.3 no.1
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    • pp.27-41
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    • 1999
  • The objective of the paper is to study the impact of changing the traditional hull design of bulk carriers by providing them with a double hull while keeping the same deadweight. It is demonstrated that by introducing the double hull the structural reliability is increased throughout the entire life and also the extend of the needed repair is reduced. The results are obtained with recently developed mathematical tools for the reliability assessment of ship hulls subjected to the existence of multiple cracks both in the stiffeners and in the plating and it models the crack growth process. The effect of corrosion is represented as time dependent. The long-term stress range acting on the elements is defined as a function of the local transverse pressure of the internal cargo and outside sea water combined with the stresses resulting from the longitudinal bending of the hull, which is a combined with the stresses resulting from the longitudinal bending of the hull, which is a combineation of horizontal and vertical bending moments. The effect of maintenance actions is modelled as a stochastic process. The results show that a different design of the midship section improves the structural safety and also the economy with respect to structural repair of bulk carriers.

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Ankyrin-B Interacts with the C-terminal Region of Hsp40

  • Min, Byung-In;Ko, Han-Suk;Kim, Chong-Rak
    • Biomedical Science Letters
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    • v.9 no.2
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    • pp.105-110
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    • 2003
  • Ankyrins are a ubiquitously expressed family of intracellular adaptor proteins involved in targeting diverse proteins to specialized membrane domains in both the plasma membrane and the endoplasmic reticulum. Canonical ankyrins are 190-220 kDa proteins expressed in most tissues and cell types and comprise a membrane-binding domain (MBD) of 24 ANK repeats, a spectrin-binding domain, a death domain and a C-terminal domain. Rescue studies with ankyrin-B/G chimeras have identified the C-terminal domain of ankyrin-B as the defining domain in specifying ankyrin-B activity, but the function of C-terminal domain of ankyrin-B is, however, not known. We report here that the C-terminal domain of ankyrin-B is capable of interacting with the C-terminal Region of Hsp40. The Hsps are induced not only by heat shock but also by various other environmental stresses. Hsps are also expressed constitutively at normal growth temperatures and have basic and indispensable functions in the life cycle of proteins as molecular chaperones, as well as playing a role in protecting cells from the deleterious stresses. The binding sites required in the interaction between C-terminal domain of ankyrin-B and C-terminal region of Hsp40 were characterized using the yeast two-hybrid system and GST-pull down assay. The interaction between ankyrin-B and Hsp40 represents the first direct evidence of ankyrin's role as chaperones.

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Bayesian reliability estimation of bivariate Marshal-Olkin exponential stress-strength model

  • Chandra, N.;Pandey, M.
    • International Journal of Reliability and Applications
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    • v.13 no.1
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    • pp.37-47
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    • 2012
  • In this article we attempted reliability analysis of a component under the stress-strength pattern with both classical as well as Bayesian techniques. The main focus is made to develop the theory for dealing the reliability problems in various circumstances for bivariate environmental set up in context of Bayesian paradigm. A stress-strength based model describes the life of a component which has strength (Y) and is subjected to stress(X). We develop the Bayes and moment estimators of reliability of a component for each of the three possible conditions, under the assumption that the two stresses (i.e. $X_1$ and $X_2$) on a component are dependent and follow a Bivariate exponential (BVE) of Marshall-Olkin distribution, the strength of a component (Y) following exponential distribution is independent of the stresses. The simulation study is performed with Markov Chain Monte Carlo technique via Gibbs sampler to obtain the estimates of Bayes estimators of reliability, are compared with moment estimators of reliabilities on the basis of absolute biases.

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An Experimental study on the Thermal Stresses in the Massive Abutment of Bridge (교량교대구조물의 수화열 및 온도응력에 대한 실험적 연구)

  • Kwon, Ki-Jun;Kim, Dong-Baek
    • Journal of the Korean Society of Hazard Mitigation
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    • v.6 no.2 s.21
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    • pp.1-7
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    • 2006
  • Recently, the massive concrete structures have been increasingly built in Korea. Many reinforced concrete structures have been reported to suffer from cracking in construction stages due to heat of hydration arising from mass concrete. This cracking may cause some serious durability problems and thus reduces the safety and service life of the structures. In this study, the stresses, strains, and temperatures were measured and the crack widths and crack Patterns were also observed in the footing and abutment structures. And the causes and mechanism in thermal cracking in the footing and abutment structures are thoroughly analysed. The comparisons of test results with analysis have been made. Efficient crack control techniques were developed form the experimental and analytical studies.

The Plant-Stress Metabolites, Hexanoic Aacid and Melatonin, Are Potential "Vaccines" for Plant Health Promotion

  • Anderson, Anne J.;Kim, Young Cheol
    • The Plant Pathology Journal
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    • v.37 no.5
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    • pp.415-427
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    • 2021
  • A plethora of compounds stimulate protective mechanisms in plants against microbial pathogens and abiotic stresses. Some defense activators are synthetic compounds and trigger responses only in certain protective pathways, such as activation of defenses under regulation by the plant regulator, salicylic acid (SA). This review discusses the potential of naturally occurring plant metabolites as primers for defense responses in the plant. The production of the metabolites, hexanoic acid and melatonin, in plants means they are consumed when plants are eaten as foods. Both metabolites prime stronger and more rapid activation of plant defense upon subsequent stress. Because these metabolites trigger protective measures in the plant they can be considered as "vaccines" to promote plant vigor. Hexanoic acid and melatonin instigate systemic changes in plant metabolism associated with both of the major defense pathways, those regulated by SA- and jasmonic acid (JA). These two pathways are well studied because of their induction by different microbial triggers: necrosis-causing microbial pathogens induce the SA pathway whereas colonization by beneficial microbes stimulates the JA pathway. The plant's responses to the two metabolites, however, are not identical with a major difference being a characterized growth response with melatonin but not hexanoic acid. As primers for plant defense, hexanoic acid and melatonin have the potential to be successfully integrated into vaccination-like strategies to protect plants against diseases and abiotic stresses that do not involve man-made chemicals.

A mesoscale stress model for irradiated U-10Mo monolithic fuels based on evolution of volume fraction/radius/internal pressure of bubbles

  • Jian, Xiaobin;Kong, Xiangzhe;Ding, Shurong
    • Nuclear Engineering and Technology
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    • v.51 no.6
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    • pp.1575-1588
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    • 2019
  • Fracture near the U-10Mo/cladding material interface impacts fuel service life. In this work, a mesoscale stress model is developed with the fuel foil considered as a porous medium having gas bubbles and bearing bubble pressure and surface tension. The models for the evolution of bubble volume fraction, size and internal pressure are also obtained. For a U-10Mo/Al monolithic fuel plate under location-dependent irradiation, the finite element simulation of the thermo-mechanical coupling behavior is implemented to obtain the bubble distribution and evolution behavior together with their effects on the mesoscale stresses. The numerical simulation results indicate that higher macroscale tensile stresses appear close to the locations with the maximum increments of fuel foil thickness, which is intensively related to irradiation creep deformations. The maximum mesoscale tensile stress is more than 2 times of the macroscale one on the irradiation time of 98 days, which results from the contributions of considerable volume fraction and internal pressure of bubbles. This study lays a foundation for the fracture mechanism analysis and development of a fracture criterion for U-10Mo monolithic fuels.

Differential expression and in situ localization of a pepper defensin (CADEFl) gene in response to pathogen infection, abiotic elicitors and environmental stresses in Capsium annuum

  • Do, Hyun-Mee;Lee, Sung-Chul;Jung, Ho-Won;Hwang, Byung-Kook
    • Proceedings of the Korean Society of Plant Pathology Conference
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    • 2003.10a
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    • pp.78.2-79
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    • 2003
  • Pepper defensin ( CADEFl) clone was isolated from cDNA library constructed from pepper leaves infected with avirulent strain Bv5-4a of Xanthomonu campestris pv. vesicatoria. The deduced amino acid sequence of CADEFl is 82-64% identical to that of other plant defensins. Putative protein encoded by CADEFl gene consists of 78 amino acids and 8 conserved cysteine residues to form four structure-stabilizing disulfide bridges. Transcription of the CADEF1 gene was earlier and stronger induced by X campestris pv. vesicatoria infection in the incompatible than in the compatible interaction. CADEF1 mRNA was constitutively expressed in stem, root and green fruit of pepper. Transcripts of CADEFl gene drastically accumulated in pepper leaf tissues treated With Salicylic acid (SA), methyl jasmonate (MeJA), abscisic acid (ABA), hydrogen Peroxide (H$_2$O$_2$), benzothiadiazole (BTH) and DL-${\beta}$-amino-n-butyric acid (BABA). In situ hybridization results revealed that CADEF1 mRNA was localized in the phloem areas of vascular bundles in leaf tissues treated with exogenous SA, MeJA and ABA. Strong accumulation of CADEF1 mRNA occurred in pepper leaves in response to wounding, high salinity and drought stress. These results suggest that bacterial pathogen infection, abiotic elicitors and some environmental stresses may play a significant role in signal transduction pathway for CADEF1 gene expression.

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OsATG10b, an Autophagosome Component, Is Needed for Cell Survival against Oxidative Stresses in Rice

  • Shin, Jun-Hye;Yoshimoto, Kohki;Ohsumi, Yoshinori;Jeon, Jong-seong;An, Gynheung
    • Molecules and Cells
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    • v.27 no.1
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    • pp.67-74
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    • 2009
  • Autophagy degrades toxic materials and old organelles, and recycles nutrients in eukaryotic cells. Whereas the studies on autophagy have been reported in other eukaryotic cells, its functioning in plants has not been well elucidated. We analyzed the roles of OsATG10 genes, which are autophagy-related. Two rice ATG10 genes - OsATG10a and OsATG10b - share significant sequence homology (about 75%), and were ubiquitously expressed in all organs examined here. GUS assay indicated that OsATG10b was highly expressed in the mesophyll cells and vascular tissue of younger leaves, but its level of expression decreased in older leaves. We identified T-DNA insertional mutants in that gene. Those osatg10b mutants were sensitive to treatments with high salt and methyl viologen (MV). Monodansylcadaverine-staining experiments showed that the number of autophagosomes was significantly decreased in the mutants compared with the WT. Furthermore, the amount of oxidized proteins increased in MV-treated mutant seedlings. These results demonstrate that OsATG10b plays an important role in the survival of rice cells against oxidative stresses.