• Proceedings of the Korean Vacuum Society Conference
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• 1997.07a
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• pp.23-23
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• 1997

• Proceedings of the Korean Vacuum Society Conference
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• 1997.07a
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• pp.28-28
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• 1997

• Korean Journal of Medicinal Crop Science
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• v.17 no.2
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• pp.109-114
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• 2009

Rhubarb is the well-known and frequently used herbal medicine for the treatment of constipation, inflammation, and cancer. As described in the Korea and Chinese Pharmacopoeia, rhubarb consists of the roots and rhizomes of Rheum palmatum, R. officinale, and R. tanguticum. However, the pharmacological differences among rhubarb have not been scientifically established. In the present study, we investigated and compared the inhibitory effects of 70% ethanolic extracts from R. palmatum (RPE), R. officinale (ROE), R. nobile (RNE), and R. franzenbachii (RFE) on the production of inflammatory mediators, nitric oxide (NO), prostaglandin $E_2$ ($PGE_2$), interlukin-1beta ($IL-1{\beta}$), and tumor necrosis factor-alpha ($TNF-{\alpha}$) in RAW 264.7 macrophage cells. ROE, RNE, and RFE significantly inhibited the release of NO, $PGE_2$, $IL-1{\beta}$, and $TNF-{\alpha}$. RPE significantly reduced the release of $IL-1{\beta}$, but not NO, $PGE_2$, and $TNF-{\alpha}$. Overall, RFE was found to inhibit the release of $PGE_2$ and $IL-1{\beta}$, to a far greater degree than RPE, ROE, and RNE. Our results indicate that RFE possess the strongest anti-inflammatory activity among 4 tested rhubarb.

• Journal of the Ergonomics Society of Korea
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• v.25 no.2
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• pp.11-22
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• 2006

The muscular-skeletal disorders(MSDs) that have become a major issue recently in Korean industrial safety area are mainly caused by manual material handling task. The objective of this study is to provide scientific data for the establishment of work safety standard for Korean workers through the experiments of lifting task under various conditions, in order to prevent the muscular-skeletal disorders in the industrial work site. Eight male college students were recruited as participants. Three different lifting frequencies(1, 3, 5 lifts/min) and three twisting angles(including the sagittal plane and two asymmetric angles; i.e., 0°, 45°, 90°) for symmetric and asymmetric tasks, respectively, with three lifting range from floor to knuckle height, knuckle to shoulder, floor to shoulder height for one hour's work shift using free style lifting technique were studied. The maximum acceptable weight of load(MAWL) was determined under the different task conditions, and the oxygen consumption, heart rate, and RPE were measured or recorded while subjects were lifting their MAWLs. The results showed that: (1) The MAWLs were significantly decreased as the task frequency and task angle increased.; (2) The heart rate, oxygen consumption, RPE significantly increased with an increase in lifting frequency although maximum acceptable weight of lift decreased.; (3) The highest heart rate and oxygen consumption was recorded at the lifting range of floor to shoulder, followed by floor to knuckle and knuckle to shoulder.; (4) The RPE value showed that subjects perceived more exertion at the high frequency rate of lifting task and lifting range of floor to shoulder height. (5) The modeling for MAWL using isometric strength, task angle and lifting frequency were developed. It is expected that use of the results provided in this study may prove helpful in reducing MMH hazards, especially from lifting tasks for Korean, and can be used as a basis for pre-employment screening.

• Journal of International Academy of Physical Therapy Research
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• v.1 no.1
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• pp.36-44
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• 2010

This study has been conducted on the subjects of eight undergraduate students with abdominal obesity and eight undergraduate students with normal weight to find out correlation between substantial fatigue and Ratings of perceived exertion through analysis of their blood components when they took exercises to strengthen their abdominal muscular power. Comparatively analyzing HDL-C, LDL-C and lactic acid before and after they took sit-up at level of RPE 19-20, no statistically significant differences in HDL, LDL, lactic acid measures were observed between groups, but a significant difference in RPE was noted between groups(p<0.05) Our findings suggest that control group showed no significant difference in increase of fatigue material whereas the obese group showed a lower frequency of sit-up, though both groups took the same abdominal exercise. Additionally, the lower frequency of sit-up in obese group results from relatively higher Ratings of perceived exertion rather than increase of substantial fatigue material. This study invites future research that examines the effect of a comprehensive obesity exercise program combined with dietetic on ratings of perceived exertion in individuals with obesity.

• Journal of Nutrition and Health
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• v.38 no.2
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• pp.117-124
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• 2005

We investigated the effects of prolonged exposure in hot environmental condition and ingestion of fluid on various physiological variables including plasma glucose, lactate, the rating of perceived exertion (RPE), and heart rate as well as golf putting performance. Six male professional golfers were voluntarily participated in three different putting trials which were separated by seven days of time interval period. Three different putting trials were conducted at either 20℃ or 32℃, or 32℃ + Fluid ingestion. Performing 32℃ + Fluid ingestion trial, all subject ingested sport drink as much as their body mass was decreased. For each experiment, all subjects were undertaken total 48 putting, which separated by four x 12 putting in four different time points (i.e., Rest, 1 hr, 2 hr, and 3 hr). Plasma glucose concentration was significantly decreased with hot ambient condition but it was almost fully recovered by fluid ingestion. Plasma lactate concentration was significantly higher when subjects were exposed in hot environmental condition, and it did not change with fluid ingestion. There was a no different in putting performance and psychological fatigue level (performed by GRID test) at any environmental conditions. The RPE, commonly used for evaluating of physical fatigue level, was significantly dropped by fluid ingestion which indicates lower physical fatigue level. In addition to this, heart rate (HR) was also significantly decreased after fluid ingestion. Based on these results, it was concluded that the ingestion of fluid during prolonged exposure in hot ambient condition decrease the degree of physical fatigue levels and heart rate, which will possibly improve the golf performance when exposed in extreme weather condition in summer. (Korean J Nutrition 38(2): 117～124, 2005)

• The korean journal of orthodontics
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• v.21 no.1 s.33
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• pp.17-29
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• 1991

The purpose of this study was to provide quantitative data describing the effect of rapid palatal expansion (RPE) on nasal airway resistance (NAR). RPE is an orthopedic procedure which is commonly used to widen the maxilla in skeletal Class III patients. 18 subjects (9 males and 9 females, mean age: 10 years 7 months) were selected from the Orthodontics in Yongdong Severance Hospital. Recordings of NAR were taken by active anterior method prior to expansion, immediately after desired maximum expansion, and after approximately 3 months and 6 months, and 1 year. All data was recorded and statistically processed with the SPSS program of IBM PC system. The results are as followings . 1. The average initial NAR of the subjects was 3.84 cm $H_2O/LPS\;(SD{\pm}1.34)$. It was greater than the average NAR of the normal subjects. 2. Among 18 subjects, 9 subjects showed reduction of NAR and 9 subjects showed no specific change of NAR after expansion. 3 An average reduction in NAR after immediately expansion was statistically significant at the 0.05 level. 4. The reduction appeared stable throughout the post treatment observation period of 1 year after expansion. From these results, it was suggested that RPE is a useful method to reduce NAR.

• Polymer(Korea)
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• v.28 no.6
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• pp.460-467
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• 2004

The polymer blends of waste poly(vinyl chloride) (RPVC) and waste polyethylene (RPE) were prepared by melt mixing. Their morphologies and rheological properties were investigated and torque changes were also measured. Comparing the torques calculated by the log additivity rule with measured torque changes, the polymer blends showed the large negative deviation behavior (NDB) due to their incompatibility. The shear viscosities of the blends decreased with increasing shear rates, showing shear thinning behavior. The shear viscosity of the blends with compatibilizer was larger than that of the blends without compatibilizer. SEM micrographs of the strands after measurement showed that the domain size of the blends was slightly enlarged with increasing the shear rate. Also, RPVC domain size was larger in the core-sections of the strands from capillary viscometer than in the surface region.

• Molecules and Cells
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• v.43 no.7
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• pp.632-644
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• 2020

The molecular mechanism underlying autophagy impairment in the retinal pigment epithelium (RPE) in dry age-related macular degeneration (AMD) is not yet clear. Based on the causative role of poly(ADP-ribose) polymerase 1 (PARP1) in RPE necrosis, this study examined whether PARP1 is involved in the autophagy impairment observed during dry AMD pathogenesis. We found that autophagy was downregulated following H₂O₂-induced PARP1 activation in ARPE-19 cells and olaparib, PARP1 inhibitor, preserved the autophagy process upon H₂O₂ exposure in ARPE-19 cells. These findings imply that PARP1 participates in the autophagy impairment upon oxidative stress in ARPE-19 cells. Furthermore, PARP1 inhibited autolysosome formation but did not affect autophagosome formation in H₂O₂-exposed ARPE-19 cells, demonstrating that PARP1 is responsible for impairment of late-stage autophagy in particular. Because PARP1 consumes NAD⁺ while exerting its catalytic activity, we investigated whether PARP1 impedes autophagy mediated by sirtuin1 (SIRT1), which uses NAD⁺ as its cofactor. A NAD⁺ precursor restored autophagy and protected mitochondria in ARPE-19 cells by preserving SIRT1 activity upon H₂O₂. Moreover, olaparib failed to restore autophagy in SIRT1-depleted ARPE-19 cells, indicating that PARP1 inhibits autophagy through SIRT1 inhibition. Next, we further examined whether PARP1-induced autophagy impairment occurs in the retinas of dry AMD model mice. Histological analyses revealed that olaparib treatment protected mouse retinas against sodium iodate (SI) insult, but not in retinas cotreated with SI and wortmannin, an autophagy inhibitor. Collectively, our data demonstrate that PARP1-dependent inhibition of SIRT1 activity impedes autophagic survival of RPE cells, leading to retinal degeneration during dry AMD pathogenesis.

• Journal of Korea Society of Industrial Information Systems
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• v.9 no.1
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• pp.56-62
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• 2004

This paper examined the change in reaction time and accuracy of mental work by physical activity. A treadmill-equipped instrument is used to attain several levels of physical activity. Subjects were recruited from college students and football players; and they were instructed to run on a treadmill at different speeds. In order to determine the individual levels of physical activity of subjects, in this paper, Borg's-RPE scales which indicates subjective levels of physical activity were obtained. And reaction time was evaluated before and after running by arithmetic calculation test Restricted within the limit of this experiment, the results of this study showed that arithmetic calculation performance as a scale of accuracy of mental work rather increase after the exercise even though there are slight difference among the subjects.