• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.1 no.1
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• pp.68-73
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• 2020

Korean fir (Abies koreana) is an evergreen coniferous tree species that is unique to South Korea. A. koreana is found in a limited sub-alpine habitat and is considered particularly vulnerable to climate change. Identification of populations vulnerable to climate change is an important component of conservation programs. In this study, a heat stress-induced transcriptome RNA-seq dataset was used to identify a subset of six genes for assessment as candidate marker genes for ecologically vulnerable populations. Samples of A. koreana were isolated from ecologically stable and vulnerable regions of the Halla and Jiri mountains, and the expression levels of the six candidate markers were assessed using quantitative real-time polymerase chain reaction. All six of the candidate genes exhibited higher expression levels in samples from vulnerable regions compared with stable regions. These results confirm that the six high temperature-induced genes can be used as diagnostic markers for the identification of populations of A. koreana that are experiencing stress due to the effects of climate change.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.6_2
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• pp.961-968
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• 2022

Hydrogen embrittlement leads to the damages in bolts, nut, especially, high pressure valves, in the semiconductor facilities, hydrogen vehicles, hydrogen stations and so on. Monel material has higher strength than SUS material. Therefore, even though Monel material with special alloy is usually used to prevent the hydrogen embrittlement, it needs powerful drawing system to manufacture the rectangular or hexagonal bar using circular bar. The purpose of this study is to investigate the characteristics of plastic deformation of Monel material and 2 rollers of rolling unit in plastic limit through numerical analysis. As the results, it was predicted that, based on mean stress, as the rolling step was increased, the rolling force of rolling unit was decreased. In addition, the heat treatment for Monel material was needed because of residual stress due to plastic deformation. As for rollers, the roller was safe about 1.86 times compared with that of ultimate strength. In this study, as the roller 2 showed larger stress than roller 1, thus, roller 2 should be designed carefully to guarantee the safety. Further it was confirmed that the reaction force of roller could be helpful in bearing design.

• Journal of Ginseng Research
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• v.3 no.2
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• pp.168-186
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• 1979

Three hundred gram of Korean ginseng root was extracted with 95% ethanol on a boiling water bath for about 300 hr. Evaporation of alcohol yieled 50.2g of dark brown residue which was used by dissolving 4 mg of the residue in 1 ml of physiological saline. The ginseng group and the saline group received each day 0.5 ml per 100 g body weight of ginseng extract and physiological saline, respectively. Both the ginseng and saline group with stress were exposed to positive radial acceleration (1∼29g), cold (5$^{\circ}C$, 0$^{\circ}C$ &-10$^{\circ}C$) and heat (35$^{\circ}C$) environment, and surgical stress. After termination of the last stress, the tolerance, body weight, visceral organ weight, basal metabolism rate, rectal temperature, the number of erythrocyte and leucocyte, hemoglobin level, hematocrit ratio, total serum protein content and it's fraction and the content of adrenal ascorbic acid in the experimental animal exposed to stress were measured and at the corresponding periods, the same measurements were also carried out with the ginseng and the saline groups without stress exposure (serving as control). Results obtained were as follows. 1. Administration of ginseng does depressed the decrease of the tolerance, body weight, visceral organ weight, basal metabolism rate, the number of erythrocyte, hemoglobin value, hematocrit ratio and the A/G ratio in the mice and rats exposed to various stress. 2. The change of the rectal temperature, eosinophile counts, total serum protein content and the content of adrenal ascorbic acid of ginseng group that exposured to various stress facilitates the reaction to, and accelerates the recovery from the stress. 3. Even after hypophysectomy which served the link between the central and the peripheral portion of the stress mechanism, the adrenal ascorbic acid content of ginseng group decreased significantly more than that of the saline group 30 min. after administration of ACTH, while the value approached the normal level significantly closer in the ginseng group than in the saline group 1 and 2 hr after ACTH administration. Judging from the above results, it is concluded that administration of ginseng extract tolerated the experimental animals under the environment of stressfu1 stmuli, although the ginseng has no significant influence upon the stress mechanism in the absence of stressful stimuli. The site of action of the ginseng appears to be in the peripheral portion of the stress mechanism.

• Journal of Korean Academy of Nursing
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• v.33 no.6
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• pp.847-855
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• 2003

Purpose: This study was done to develop a bereaved family care program by identifying characteristics of a grief healing process in a child loss. Method: The subjects were five bereaved mothers who have lost their children with cancer. Data was collected with in-depth interviews using grief phase assessment tool and grief reaction assessment tool from 1, February, 2001 to 31 August, 2002. Data was analyzed on the basis of two tools. Result: Process of grief in general was as follows: evading phase was within one week - one month, confrontation phase was 5 - 12 months, and reconciliation phase was after 9 months and still going on when the study was finished. Grief reaction in five (physical, cognitive, emotional, social, and spiritual) dimensions was stabilized when the phase moved into reconciliation phase. Influencing factors were intimacy and expectation towards child, social support, personality, prior loss experience, coping style, religion, culture, family cohesion, openness of communication, and stress events. Conclusion: These results suggest that a bereaved family care program considering characteristics of Korean culture should be developed and activated.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.1
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• pp.131-137
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• 2013

Gas springs have been widely used in motor vehicles as well as in most areas of industry. Instead of coil springs, these gas springs are easily operated to extrusion process or compression process the doors because $N_2$ gas with high pressure and oil are charged in tube. Gas spring sustain the constant elasticity change rate in the high reaction force and long stroke, and they have compact design, appearance and an excellent assembling ability to be mounted easily with any applicatory products. By means of these aspects, gas springs have been widely used in stead of coil springs in the over all industries. In this study, using acommonly used program, ANSYS, the basic research about the heat transfer and equivalent stress change of bimetal.

• Fashion & Textile Research Journal
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• v.6 no.3
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• pp.384-392
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• 2004

The purpose of this study is in development of effective filter-type polymer adsorbent for removal of pollutants from wastewater by UV irradiation graft polymerization. Photografting of acrylic acid (AA) on polypropylene (PP) nonwoven fabric using benzophenone (BP) as a photosensitizer was investigated. Inhibition of homopolymerization was achieved by adding various concentrations of $FeSO_4{\cdot}7H_2O$, $CuSO_4{\cdot}5H_2O$ and Mohr's salt. As AA concentration was increased, the degree of grafting was increased as to a specific value and then decreased, and the effect of BP concentration showed the same tendency. It was also found that the degree of grafting increased with reaction time and reaction temperature. Addition of the polyfunctional monomers and $H_2SO_4$ to the grafting system accelerated the photografting. The melting temperature, molecular weight and breaking stress and breaking strain were decreased with the increase in the degree of grafting.

• Journal of Microbiology and Biotechnology
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• v.21 no.3
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• pp.277-283
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• 2011

Glyoxalase I catalyzes the conversion of methylglyoxal to S-D-lactoylglutathione in the presence of glutathione. The structural gene of glyoxalase I (GLO1) was cloned from an osmotolerant yeast, Candida magnoliae, which produces a functional sweetener, erythritol, from sucrose. DNA sequence analysis revealed that the uninterrupted open reading frame (ORF) of C. magnoliae GLO1 (CmGLO1) spans 945 bp, corresponding to 315 amino acid residues, and shares 45.2% amino acid sequence identity to Saccharomyces cerevisiae Glo1. The cloned ORF in a multicopy constitutive expression plasmid complemented the glo1 mutation of S. cerevisiae, confirming that it encodes Glo1 in C. magnoliae. The responses of CmGLO1 to environmental stresses were different from those of S. cerevisiae, which only responds to osmotic stress. An enzyme activity assay and reverse transcription polymerase chain reaction revealed that the expression of CmGLO1 is induced by stress inducers such as methylglyoxal, $H_2O_2$, KCl, and NaCl. The GenBank Accession No. for CmGLO1 is HM000001.

• Clinical and Experimental Pediatrics
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• v.64 no.6
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• pp.251-259
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• 2021

Psychogenic nonepileptic seizures (PNES) is a neuropsychiatric condition that causes a transient alteration of consciousness and loss of self-control. PNES, which occur in vulnerable individuals who often have experienced trauma and are precipitated by overwhelming circumstances, are a body's expression of a distressed mind, a cry for help. PNES are misunderstood, mistreated, under-recognized, and underdiagnosed. The mind-body dichotomy, an artificial divide between physical and mental health and brain disorders into neurology and psychiatry, contributes to undue delays in the diagnosis and treatment of PNES. One of the major barriers in the effective diagnosis and treatment of PNES is the dissonance caused by different illness perceptions between patients and providers. While patients are bewildered by their experiences of disabling attacks beyond their control or comprehension, providers consider PNES trivial because they are not epileptic seizures and are caused by psychological stress. The belief that patients with PNES are feigning or controlling their symptoms leads to negative attitudes of healthcare providers, which in turn lead to a failure to provide the support and respect that patients with PNES so desperately need and deserve. A biopsychosocial perspective and better understanding of the neurobiology of PNES may help bridge this great divide between brain and behavior and improve our interaction with patients, thereby improving prognosis. Knowledge of dysregulated stress hormones, autonomic nervous system dysfunction, and altered brain connectivity in PNES will better prepare providers to communicate with patients how intangible emotional stressors could cause tangible involuntary movements and altered awareness.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2005.05a
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• pp.554-559
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• 2005

It seems to be dangerous to use a cellular phone while driving since it increases driver's mental stress and makes driver's reaction time slow. This study is to investigate driver's psycho-physiological responses on mobile telephoning while driving. Among the three experimental factors (mobile-phone types, message IODs over mobile-phone, road types), only the message IODs over mobile-phone changed R-R intervals of electrocardiograph significantly. This result suggests that the regulations on the mobile telephoning while driving be changed.

• Journal of Industrial Technology
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• v.31 no.B
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• pp.81-90
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• 2011

Centrifuge modeling and numerical analysis on works of breakwater construction were performed to investigate the behavior of caisson type of breakwater and foundation treated with the method of DCM (Deep Cement Mixing) under the condition of wave action in field. In centrifuge modeling, construction sequence of breakwater caisson such as preparation of ground, treatment of DCM, installation of rubble mound, placement of breakwater caisson and lateral loading on the breakwater due to wave action were reconstructed. Lateral movement of model breakwater and ground reaction in the vertical direction were monitored during test. Stress concentration ratio between the untreated ground and the treated ground with DCM was evaluated from measurement of vertical stresses on each ground. Numerical analysis with the software of PLAXIS was carried to compare with Results of centrifuge model test. It was found that stability of model breakwater was maintained during stage of construction and the compared results about stress concentration ratio were in relatively good agreements.