• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.81-82
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• 2006

This paper presents the influence of the compositions of sintered Ti-Ni alloys on their thermo-mechanical properties. The Ti-Ni alloys having various compositions from 50at%Ni to 51at%Ni were sintered using elemental Ti and Ni powders by a pulse-current pressure sintering equipment. The deformation resistance in stress-strain curves increased with an increase in Ni content. In the case of Ti-50at%Ni, tensile strength and elongation were more than 500 MPa and 7%, respectively. The increase in Ni content also makes the transformation temperatures lower. The deformation resistance at a test temperature change from 293K and 353K in isothermal tensile test increased with elevating test temperature.

• Food Science and Preservation
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• v.30 no.5
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• pp.785-796
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• 2023

The aim of this study was to elucidate chemical structures and rheological properties of arabinogalactans (AGs) isolated from three legumes including black gram (BG), great northern bean (GNB), and California small white bean (CSWB). The ratio of galactose to arabinose (G/A) in three legumes increased in the order of BG > GNB > CSWB. The rheological measurements of 1-5% (w/v) AG solutions revealed Newtonian and non-Newtonian flow behaviors. BG exhibited yield stress, indicating plastic behavior. Small-amplitude oscillatory tests indicated viscoelastic properties of BG, GNB, and CSWB ranging from solid-like, paste-like, and liquid-like behaviors, respectively. Small-strain oscillatory tests were conducted to assess the structure recovery of the AGs after pre-shearing. G" values of BG and GNB increased, but those of CSWB remained constant after shearing. These results suggest that the chemical structures of the AGs, particularly their G/A ratios, influence their rheological properties.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.8
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• pp.1116-1126
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• 2008

The objective of this study was to investigate the expression and localization of heat shock protein 70 (Hsp70) and its mRNA in the heart, liver, and kidney of acutely heat-stressed broilers at various stressing times. Male AA broilers (n = 100) were randomly divided into 5 groups of 20 birds per group. After 30 d of adaptive feeding at ambient temperature, 80 experimental broilers were suddenly heat stressed by increasing the environmental temperature from $22{\pm}1^{\circ}C$ to $37{\pm}1^{\circ}C$. The 4 groups were heat stressed for 2, 3, 5, and 10 h, respectively. The localizations of Hsp70 protein and mRNA, determined by immunohistochemical staining and in situ hybridization, respectively, were demonstrated to be tissue dependent, implying that different tissues have differential sensibilities to heat stress. Intense Hsp70 staining was identified in the vascular endothelial cell of heart, liver and kidney, suggesting an association between expression of Hsp70 in vascular endothelial cell and functional recovery of blood vessels after heat shock treatment. Ante-mortem heat stress had a significant effect on the expression of Hsp70 protein and mRNA. The quantitation of Hsp70 protein and mRNA were both time and tissue dependent. During the exposure to heat stress, the heart, liver and kidney of broiler chickens exhibited increased amounts of Hsp70 protein and mRNA. The expression of hsp70 mRNA in the heart, liver and kidney of heat-stressed broilers increased significantly and attained the highest level after a 2-h exposure to elevated temperatures. However, significant elevations in Hsp70 protein occurred after 2, 5, and 3 h of heat stressing, respectively, indicating that the stress-induced responses vary among different tissues.

• The Journal of Korean Obstetrics and Gynecology
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• v.20 no.4
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• pp.210-216
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• 2007

Purpose: The effects of non-operation treatment on the stress urinary incontinence is low by 20-50%. And the way of operation has higher recovery, but it also has problems of the aftereffects and invasive aspects. So It is demanded for improvement of non-invasive to relieve this disease. Methods: The patient was 55-year-old woman who had suffered from incontinence six years ago. The patient was diagnosed by stress urinary incontinence, and treated by Herbal medicine and acupuncture treatment. The progress of symtoms was evaluated by checking the score of doing multiplication the severity and the frequency. Results: After the oriental medical treatments, the clinical score of stress urinary incontinence was improved from 12 to 0. Conclusion: This study shows that the oriental medicine may be considered for the non-invasive of stress urinary incontinence, and the study of effect is more needed.

• Transactions of Materials Processing
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• v.7 no.2
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• pp.168-176
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• 1998

Hot workability of the AA5083 alloy ws investigated by torsion test at temperature ranges of $350{\sim}520^{\circ}C$ and strain rates of 0.5, 1.0, and 3.0/sec. The flow stress and hot ductility of the AA5083 alloy as a function of deformation variables such as temperature and train rate were studied. The microstructural evolution of the AA5083 alloy was studied in relation to Zener-Hollomon parameter (Z=exp( /RT) Also the hot restoration mechanism of the AA5083 alloy was small when Z val-ues were higher than $1.73{\times}1016/sec(370^{\circ}C,\;0.5/sec)$ In addition the difference microstructures during hot deformation. It was found that the increase of flow curves and deformed microstructures during hot deformation. It was found that the increase of flow stress of the AA5083 alloy was small when Z val-ues were higher than $1.73{\times}1016/sec(370^{\circ}C.\;0.5/sec)$. However under the low Z values less than $1.73{\times}1016/sec(370^{\circ}C,\;0.5/sec)$ the flow stress increase with increasing the Z values. The large dispersoid particles in the matrix grain decreased the flow strain of the AA5083 alloy because it caused the stress concentration during hot deformation.

• Natural Product Sciences
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• v.15 no.4
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• pp.213-221
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• 2009

Longanae Arillus (the rind of fruits of Dimocarpus longan) has been consumed for the treatment of insomnia and anxiety in Asia. To provide further scientific basis to traditional uses of this fruit on insomnia, we evaluated the effects of methanol extract of Longanae Arillus (MELA) on the alteration of sleep architecture and electroencephalogram (EEG) power spectra in acutely and chronically restraint-stressed rats. Following postsurgical recovery, Polygraphic signs of sleep-wake activities were recorded for 24 h after MELA administration in rats. Rats in the acute stress and chronic stress were administered with MELA for 10 days. On the $8^{th},\;9^{th}\;and\;10^{th}$ day of MELA administration, the rats were stressed for 3 h once per day. On the $10^{th}$ day and 1 h after MELA administration, the rats were stressed once for 22 h in the chronic stress group. Acute and chronic stress induced alternations in cortex EEG recordings during non-rapid eye movement (NREM), rapid eye movement (REM) sleep and wakefulness. MELA shortened the total and REM sleep and increased the wakefulness in night time recording without changing daytime recordings. Chronic stress increased wakefulness and REM sleep, decreased total and NREM sleep in the daytime recording, and increased REM and decreased NREM sleep without changing total sleep and wakefulness in night time recording. These findings suggest that MELA ameliorated the alterations in REM and NREM sleep of acutely and chronically stressed rats via modulation of cortical ${\alpha}-$, ${\theta}-$ and ${\delta}-$ wave activity.

• Journal of Ginseng Research
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• v.34 no.1
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• pp.30-40
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• 2010

The present investigation was conducted to evaluate the regulation of sleep architecture by the red ginseng water extract (RGE) in acutely and chronically restraint stressed rats. Adult rats were fitted with sleep.wake recording electrodes. Following post-surgical recovery, rats were extensively habituated for freely moving polygraphic recording conditions. Polygraphic signs of sleep-wake activities were recorded for 24 h after RGE administration and induction of stress and were analyzed to understand the regulation of sleep architecture. Acute stress decreased wakefulness and increased total sleep, non-rapid eye movement (NREM) sleep, and rapid eye movement (REM) sleep in both the daytime and nighttime recording. RGE shortened the daytime NREM and REM sleep, without changing the wakefulness and total sleep. RGE increased nighttime wakefulness, and decreased total, NREM and REM sleep. Chronic stress increased wakefulness and decreased total sleep in the daytime recording, and increased REM and decreased NREM sleep in both the day and night time recording. RGE ameliorated chronic stress and induced alterations of REM and NREM sleep in the day and night time sleep architecture. Acute and chronic stress could also induce alternations in cortex electroencephalogram (EEG) recording during NREM, REM sleep and wakefulness. These findings suggest that RGE may modulate the sleep behavior in acutely and chronically stressed rats and the ameliorating effect of RGE on the sleep architecture may involve in modulation of $\alpha$-, $\theta$- and $\delta$- wave activities of the cortical EEG.

• Women's Health Nursing
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• v.19 no.4
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• pp.211-218
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• 2013

Purpose: The purpose of study was to examine effects of aromatherapy on stress, sleep, nausea and vomiting of women after laparoscopic hysterectomy. Methods: The participants were 60 women who had laparoscopic hysterectomy: experiment group for aromatherapy (n=30) and control group for routine care (n=30). The experimental group received inhalation aromatherapy for 5 minutes, twice; the first was done right after the operation, the second was at 9 pm before sleep on the same day-while the control group had no inhalation. Data were collected from July to September, 2012 at G hospital. Results: The degree of psychological stress was not significantly different between two groups (t=-1.96, p=.054). Yet, there were significant differences between two groups for degree of physiological stress (t=-3.20, p=.002), the level of cortisol (t=-2.01, p=.049), the score of sleep status (t=2.47, p=.016), the score of sleep satisfaction (t=2.43, p=.018), and the score for nausea and vomiting (t=-2.58, p=.012). Conclusion: Inhalation aromatherapy using the mixed oil of lavender, mandarin, and marjoram was effective in decreasing the level of physiological stress, cortisol, and the score for nausea and vomiting, and also allowed the participants to have a better sleep. Therefore, inhalation aromatherapy could be effective in improving the quality of life of these women during recovery.

• Journal of Korean Academy of Nursing
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• v.24 no.3
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• pp.389-412
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• 1994

This study was done to investigate stress and coping methods of mothers with brain disease children. The subjects for this study were obtained by taking a sample of mothers with brain disease children hospitalized in neurosurgery ward of K medical center in Seoul from Nov. 20, 1992 to Mar. 10, 1993. The collected date were analized by S.P.S.S. program(frequency, percentage, mean, t-test, ANOVA, Pearson Correlation). The results of the study were as follow. 1. The mean of the degree of mothers' stress was 3.681. Of the stress categories, illness treatment (4.216) was highest, and the next were in order of ill-ness status and prognosis(4.154) , family relation-ships and personal roles(3.202), interpersonal relationships(2.916). 2. The mean of the degree of mothers' coping method was 2.930. Of the coping method categories, communication with medical team or parents in similar situations(3.332) was highest, and the next were in or-der of family cooperation and optimistic thought about the situation(3.241), reforcement of self esteem and maintenance of psychological stability(2.538). 3. There was not seen a stastically significant correlation between stress factors and coping methods of mothers. But with categories, the higher the stress to illness status and prognosis was, the hight coping methods' degree of communication with medical team or parents in similar situations was shown a positive correlation, if not high (r=.2776, P=.046) . And the higher the stress to illness treatment was, the higher coping methods' degree of communication with medical team or parents in simial situations was shown a positive correlation, if not high (r=.2727, P=.049). 4. With the difference of stress according to mothers' general characteristics, religion and monthly income shew a statically significant difference. The mothers' group who have a religion shew the higher degree of stress(t=-3.17, P=.003), The group who get the most income shew highest degree of stress (F=.4693, P=.0156). With the difference of coping according to mothers' general characteristics, the most support-ing person, satisfaction with husbands and mothers' own health status shew a statistically significant difference. The group who get the most support from parents-in-law(F=3.7508, P=.013), the group who are much satisfied with husband(F=3.589, P=.016), and the group whose health status are good(F=3.3675, P=.046), shew the highest coping degree. 5. There were no significant difference in degree of stress and coping by children's characteristics The significance of the study will be concluded as follows. 1. Investigating the stress factors, which mothers are perceiving, it will be utilized as the basic materials of nursing plan so as to reduce the stress of mothers. 2. In searching for the ways of mothers' more helpful coping methods, it shows the necessity of the active nursing intervention for the mothers in the process of coping with their stress. That is, the nurse should serve the earnest nursing as counselor, supporter, educator, and information - provider. 3. Recogning mothers as well as children with brain disease as a client, the nurse will be able to help the mother, who is taking care of the children, cope with the stress situation well, and to make a contribution to the recovery, rehabilitation, and health of the children and to the enhancement of the family' health.

• Journal of Korean Society of Forest Science
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• v.103 no.1
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• pp.129-136
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• 2014

This study aims to investigate the effect of frequency of using forest environment on workers' stress. Workers in medical and counseling industry, which is recently known to require heavy emotional burden and thus cause a lot of stress and burnout syndrome, participated in the study. We classified 370 subjects, who were working at medical and counseling service institutions in Seoul metropolitan area, into two groups according to frequency of using forest environment by conducting a screening survey. 69 subjects submitted written consent and were recruited for either forest therapy program or control-group test; the "high" group (n=27) at the high frequency of using forest environment and the "low" group (n=42) at the low level. We measured the level of stress by using psychosocial indicators such as Worker's Stress Response Inventory (WSRI), Recovery Experience Questionnaire (REQ), and Maslach Burnout Inventory-General Survey (MBI-GS) and biological ones such as heart rate variability (HRV), cortisol, and Natural Killer cell (NK cell). The results suggested that the level of stress differed by frequency. The "high" group showed significantly low scores in the depression and work sub-scale and the total score of WSRI, emotional exhaustion, professional efficacy and total score of MBI-GS, and high scores in the total score of REQ. Similar tendencies were observed in the most of other indicators of psychosocial measures. Regarding the biological indicators, the "high" group showed the highest SDNN, RMSSD and TP measures of HRV and NK Cell activity and the low cortisol, although the statistical power did not reach the significant level. Our results suggest that the subjects who use forest environment frequently show favorable stress level both psychologically and biologically.