• 대한핵의학회지
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• 제39권2호
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• pp.107-113
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• 2005

Pharmacologic stress testing for myocardial perfusion imaging is a widely used noninvasive method for the evaluation of known or suspected coronary artery disease. The use of exercise for cardiac stress has been practiced for over 60 years and clinicians are familial with its using. However, there are inevitabe situations in which exorcise stress is inappropriate. A large number of patients with cardiac problems are unable to exercise to their full potential due to comorbidity such as osteoarthritis, vascular disease and pulmonary disease and a standard exercise stress test for myocardial perfusion imaging is suboptimal means for assessment of coronary artery disease. This problem has led to the development of the pharmacologic stress test and to a great increase in its popularity. All of the currently used pharmacologic agents have well-documented diagnostic value. This review deals the physiological actions, clinical protocols, safety, nuclear imaging applications of currently available stress agents and future development of new vasodilating agents.

• 한국생활과학회지
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• 제21권3호
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• pp.407-421
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• 2012

The purpose of this study is to plan out a university students' self-development program and to verify the effect of the students in adapting themselves to college life and coping with stress from it. The program was developed as the liberal arts course for a semester and comprised 12 sessions. Each secession of a 150 minutes workshop program. The pre-test, post test regarding students adaptation to college and stress coping methods conducts upon each experimental group and each control group. Each group consisted of 50 subjects. As a result of this research, this study could come to the following conclusions. Firstly, it was found that the university students' self-development program has effect on improving students adaptation to college. Secondly, it was found that the university students' self-development program has effect on improving stress coping methods.

• Molecules and Cells
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• 제39권3호
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• pp.179-185
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• 2016

Posttranscriptional regulation of RNA metabolism, including RNA processing, intron splicing, editing, RNA export, and decay, is increasingly regarded as an essential step for fine-tuning the regulation of gene expression in eukaryotes. RNA-binding proteins (RBPs) are central regulatory factors controlling posttranscriptional RNA metabolism during plant growth, development, and stress responses. Although functional roles of diverse RBPs in living organisms have been determined during the last decades, our understanding of the functional roles of RBPs in plants is lagging far behind our understanding of those in other organisms, including animals, bacteria, and viruses. However, recent functional analysis of multiple RBP family members involved in plant RNA metabolism and elucidation of the mechanistic roles of RBPs shed light on the cellular roles of diverse RBPs in growth, development, and stress responses of plants. In this review, we will discuss recent studies demonstrating the emerging roles of multiple RBP family members that play essential roles in RNA metabolism during plant growth, development, and stress responses.

• 한국초지조사료학회지
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• 제39권3호
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• pp.153-157
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• 2019

Salicylic acid (SA) is an essential plant growth regulator that functions as a signaling molecule in plants. The purpose of this study was to clarify how the exogenous application of SA counteracts aluminum stress-induced growth and biomass yield reduction in alfalfa exposed to aluminum (Al) stress. Two-week-old alfalfa seedlings were exposed to a combination of $AlCl_3$ ($0{\mu}M$, $50{\mu}M$ and $100{\mu}M$, respectively) and SA (0.1 mM) for 72 hours. We observed, Al stress-induced plant growth inhibition and forage yield reduction are Al stress-dependent manner. A significant reduction of plant height (42.0-52.9%), leaf relative water content (13.0-21.4%), root length (35.4-48.7%), shoot fresh weight (31.2-25.9%), root fresh weight (15.4-23.3%), shoot dry weight (12.7-22.2%), roots dry weight (47.3-53.5%), were observed in alfalfa. In contrast, SA alleviated the Al-stress and enhanced growth and biomass yield in alfalfa. This study provides useful information concerning the role of SA that counteracts aluminum stress-induced growth and yield reduction in alfalfa.

• Clinical and Experimental Reproductive Medicine
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• 제42권1호
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• pp.1-7
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• 2015

Stress coping mechanisms are critical to minimize or overcome damage caused by ever changing environmental conditions. They are designed to promote cell survival. The unfolded protein response (UPR) pathway is mobilized in response to the accumulation of unfolded proteins, ultimately in order to regain endoplasmic reticulum (ER) homeostasis. Various elements of coping responses to ER stress including Perk, Ask1, Bip, Chop, Gadd34, Ire1, Atf4, Atf6, and Xbp1 have been identified and were found to be inducible in oocytes and preimplantation embryos, suggesting that, as a normal part of the cellular adaptive mechanism, these coping responses, including the UPR, play a pivotal role in the development of preimplantation embryos. As such, the UPR-associated molecules and pathways may become useful markers for the potential diagnosis of stress conditions for preimplantation embryos. After implantation, ER stress-induced coping responses become physiologically important for a normal decidual response, placentation, and early organogenesis. Attenuation of ER stress coping responses by tauroursodeoxycholate and salubrinal was effective for prevention of cell death of cultured embryos. Further elucidation of new and relevant ER stress coping responses in periimplantation embryos might contribute to a comprehensive understanding of the regulation of normal development of embryonic development and potentiation of embryonic development in vitro.

• 한국발생생물학회지:발생과생식
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• 제22권3호
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• pp.235-244
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• 2018

We investigate the effect of endoplasmic reticulum (ER) stress inhibitor treatment during parthenogenetic activation of oocytes on the ER stress generation, apoptosis, and in vitro development of parthenogenetic porcine embryos. Porcine in vitro matured oocytes were activated by 1) electric stimulus (E) or 2) $E+10{\mu}M$ Ca-ionophore (A23187) treatment (EC). Oocytes were then treated by ER stress inhibitors such as salubrinal (200 nM) and tauroursodeoxychloic acid (TUDCA, $100{\mu}M$) for 3 h prior to in vitro culture. Parthenogenetic embryos were sampled to analyze ER stress and apoptosis at the 1-cell and blastocyst stages. The x-box binding protein 1 (Xbp1) mRNA and ER stress-associated genes were analyzed by RT-PCR or RT-qPCR. Apoptotic gene expression was analyzed by RT-PCR. At the 1-cell stage, although no difference was observed in Xbp1 splicing among treatments, BiP transcription level in the E group was significantly reduced by salubrinal treatment, and GRP94 and ATF4 transcription levels in EC group were significantly reduced by all treatments (p<0.05) compared to control. In the EC group, both apoptotic genes were reduced by ER stress inhibitor treatments compared to control (p<0.05) except Caspase-3 gene by TUDCA treatment. These results suggest that the treatment of ER stress inhibitor during parthenogenetic activation can reduce ER stress, and thereby reduce apoptosis and promote in vitro development of porcine parthenogenetic embryos.

• 한국학교보건학회지
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• 제16권1호
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• pp.55-66
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• 2003

This study was conducted to evaluate the differences of perceived stress level and stress coping behavior for 360 elementary school children in rural area and 360 in urban area. The questionnaire survey was done from December 10 to December 20, 2001. The results were as follows: 1. There was no significant difference of perceived stress level between rural and urban areas, but there were significant difference of stress coping behavior between them. 2. Significant difference of perceived stress level and stress coping behavior among groups of grade was found. 3. There was significant difference of perceived stress level and stress coping behavior between male and female. 4. There was significant difference of stress coping behavior according to perceived stress levels In conclusion, perceived stress level and stress coping behavior in elementary school children were different according to their grade and sex. It is important to teach them proper stress coping method, depending on their grade and sex. But, we have to focus on the development and application of stress self-control program, which enables children to cope with stress for themselves. Based on: 1. Before starting the study, the subjects should be examined about whether they have ever been on stress education program before or not. 2. The educational environments and the development and implementation of teaching program for the proper stress coping method are needed. 3. This study was performed through the questionnaire for perceived stress level and stress coping behavior, but various methods like observation, person-to-person interview should be used for the further in-depth study.

• 아동학회지
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• 제31권2호
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• pp.151-168
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• 2010

The purpose of this study was to investigate which variables predicted parenting efficacy. The variables of interest were demographic variables regarding both the infants and mothers, infant temperament and development, maternal parenting knowledge, parenting belief, and parenting stress. The subjects consisted of 260 infants and mothers. Data on infant's temperament, parenting knowledge, parenting belief, parenting stress and parenting efficacy were gathered through maternal self-reported questionnaires. Furthermore, infant development was assessed by classroom teacher. Data were analyzed by descriptive statistics, correlation and regression analyses. Our results indicated that infant's sociability and activity, parenting knowledge about emotional development, parenting beliefs emphasizing the role of nature in infant development, low parenting stress all predicted parenting efficacy.

• Steel and Composite Structures
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• 제41권6호
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• pp.851-860
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• 2021

In this paper, a new approach of interface stress analysis in steel beam strengthened by porous FGM (Functionally Graded Materials) is presented to calculate the shear stress in the hybrid steel beam and loaded by a uniformly distributed load. The results show that there exists a high concentration of shear stress at the ends of the imperfect FGM, which might result in premature failure of the strengthening scheme at these locations. A parametric study has been conducted to investigate the sensitivity of interface behavior to parameters such as the rigidity of FGM plate (degree of homogeneity), the porosity index of FGM and the thickness of adhesive all were found to have a marked effect on the magnitude of maximum shear stress in the FGM member. we can conclude that the new approach is general in nature and may be applicable to all kinds of materials.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2019년도 추계학술대회
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• pp.21-21
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• 2019

Approximately 80% of rice field in Africa conducts in rainfed (Nishimaki 2017). The rice is damaged by water stress because fields like rainfed lowland repeat drying and humidity of soil because of impossible water control. Then water stress is one of the major limiting factors for decreasing rice yield. So, in initial growth stage, quick and efficient root development is useful way to avoid drought stress by getting water from deeper soil layer with roots elongation as the hypothesis. Daniel et al (2016) reported that NERICA1 and NERICA4 show different patterns of root plasticity for drought stress. NERICA1 has greater development of lateral root in shallow soil layer, while NERICA4 has greater development in deep root elongation to underground. This study was aimed to evaluate the effect of root development in initial growth stage on growing NERICA1 and NERICA4 under different soil moisture condition in rainfed lowland rice field. They were grown in same water condition until 35 days after sowing (35DAS), and after that each varieties were separated in dry and wet condition. The rice plants were grown until 60DAS. The results of soil moisture, the root extension angle, shoot dry weight and bleeding ratio showed that NERICA4 can mitigate dry stress from surface soil compered to NERICA1.