• Journal of Astronomy and Space Sciences
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• v.29 no.1
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• pp.51-55
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• 2012

A few high-mass X-ray binaries-consisting of an OB star plus compact companion-have been observed by Fermi and ground-based Cerenkov telescopes like High Energy Stereoscopic System (HESS) to be sources of very high energy (VHE; up to 30 TeV) ${\gamma}$-rays. This paper focuses on the prominent ${\gamma}$-ray source, LS 5039, which consists of a massive O6.5V star in a 3.9-day-period, mildly elliptical ($e{\approx}0.24$) orbit with its companion, assumed here to be an unmagnetized compact object (e.g., black hole). Using three dimensional smoothed particle hydrodynamics simulations of the Bondi-Hoyle accretion of the O-star wind onto the companion, we find that the orbital phase variation of the accretion follows very closely the simple Bondi-Hoyle-Lyttleton (BHL) rate for the local radius and wind speed. Moreover, a simple model, wherein intrinsic emission of ${\gamma}$-rays is assumed to track this accretion rate, reproduces quite well Fermi observations of the phase variation of ${\gamma}$-rays in the energy range 0.1-10 GeV. However for the VHE (0.1-30 TeV) radiation observed by the HESS Cerenkov telescope, it is important to account also for photon-photon interactions between the ${\gamma}$-rays and the stellar optical/UV radiation, which effectively attenuates much of the strong emission near periastron. When this is included, we find that this simple BHL accretion model also quite naturally fits the HESS light curve, thus making it a strong alternative to the pulsar-wind-shock models commonly invoked to explain such VHE ${\gamma}$-ray emission in massive-star binaries.

• Clinical and Experimental Reproductive Medicine
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• v.29 no.3
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• pp.167-178
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• 2002

Objective : The present study was performed to investigate whether apoptosis occur in human embryos by annexin staining and detect the expression of Fas, Fas-ligand (FasL), Bax, and Bcl-2 in human fragmented embryos derived from IVF-ET by immunofluorescence and Western blot analysis. Materials and Methods: Using annexin staining, immunofluorescence and Western blot analysis on normal and fragmented embryos, we were able to detect apoptotsis and apoptotic gene products in fragmented embryos. Result: Phosphatidylserine (PS) translocation, the marker for apoptosis, were detected frequently in fragmented embryos. Bcl-2 and Bax protein were detected in both fragmented and non-fragmented embryos. When fragmented embryos compared to normal embryos, immunofluorescent intensity of Bcl-2 tended to be lower in fragmented embryos. Bax gene expression increased in the fragmented embryos compared to the normal embryos. This result supports a model in which the molar ratio of Bcl-2 to Bax determines whether apoptosis induced or inhibited in human embryo. Fas was highly expressed in human preimplantation embryos but not FasL. It suggests that embryo may undergo apoptosis by binding with FasL produced by follicular or immune cells. Conclusion: The over expression of Bax and Fas will trigger apoptosis to lead embryo fragmentation and change embryo to be nonviable.

• Korean Journal of Psychosomatic Medicine
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• v.7 no.2
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• pp.149-157
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• 1999

Food intake and body weight are determined by a complex interaction of regulatory pathways. Leptin, the product of the ob gene, is a recently discovered hormone secreted by adipocytes, that signals the amount of adipose tissue energy stores to the brain and exerts major effects on energy homeostasis and neuroendocrine function. In addition, leptin has recently been shown to affect reproductive function in rodents and humans. The study of leptin and its effectors in the hypothalamus may provide important insights with respect to the interplay of several hypothalamic neuropeptides in regulating feeding as well as the interaction of genetics and environment in the regulation of energy homeostasis. In this review we summarise the action of leptin in the regulation of food intake and highlight a working model of the effects of environmental factors on the leptin system.

• The Journal of Korean Medicine
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• v.38 no.1
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• pp.112-124
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• 2017

Objectives: The purpose of this study is to investigate the various postpartum symptoms and the relevant factors. So it can provide fundamental data about postpartum health care. In conclusion, we can prevent and manage the postpartum disease by using this data. Methods: The subject of the present study was 94 women (63 women who completed vaginal delivery and 31 women who delivered by cesarean section) who completed labor between November 1, 2013 and January 31, 2016, at the clinic of OB&GYN. They have been taking good care of their health at postpartum clinic in Andong Woori Women Hospital. We investigated the various symptoms and situation which occurred from the moment of hospital to postnatal admission health care period, and Korean medical doctor examined the patients through the four examination methods. We classified the symptoms by maternal age, the frequency of maternal childbirth, the method of delivery, the delivery season, the term of pregnancy, the body weight of infant, the weight change of mother and the way of feeding. Results: There were no remarkable corelation in the frequency of symptoms according to maternal age, the way of delivery, the delivery season, the change of weight before and after of delivery, gestational weeks at delivery, the manner of feeding and the body weight of infants except for the frequency of maternal childbirth. Conclusion: The symptoms of hemorrhoids, the feeling of coldness and chilliness increased with increasing the frequency of maternal childbirth. Other circumstances, there was no relationship with symptoms of postpartum.

• The Journal of Korean Medicine
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• v.38 no.1
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• pp.125-133
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• 2017

Objectives: The purpose of this study is to investigate the correlation between postpartium joint diseases and maternal season. So it can prevent postpartum joint diseases and provide fundamental data about postpartum health care. Methods: The subject of the present study was 219 women (142 women who completed vaginal delivery and 77 women who delivered by cesarean section) who completed labor between November 1, 2013 and November 31, 2016, at the clinic of OB&GYN. They have been taking good care of their health at postpartum clinic in Andong Woori Women Hospital. We investigated the various symptoms and situation which occurred from the moment of hospital to postnatal admission health care period and oriental doctor examined the patients. We classified the symptoms by the age of patients, the method of delivery, the term of pregnancy, the body weight of infant, the weight change of mother and the way of feeding. Through data analysis, we investigated the correlation between maternal season and postpartum joint diseases. Results: Postpartum joint diseases were the most common among all symptoms after childbirth. Postpartum joint diseases were classified into shoulder area pain and low back pain. In low back pain, there was no significant difference between maternal season and postpartum joint diseases. In shoulder, wrist and finger pain, pain was the most severe at winter delivery. It was the most painful in winter, followed by autumn, spring and summer. Conclusion: There was a close correlation between postpartum joint disease manifestations and maternal season.

• The Korean Journal of Physiology and Pharmacology
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• v.8 no.4
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• pp.227-235
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• 2004

The aim of the present study was to examine the effect of leptin on CA release from the isolated perfused model of the rat adrenal gland, and to establish its mechanism of action. Leptin $(1{\sim}100\;ng/ml)$, when perfused into an adrenal vein of the rat adrenal gland for 60 min, enhanced a dose-dependently the secretory responses of CA evoked by ACh $(5.32{\times}10^{-3}\;M)$, DMPP $(10^{-4}\;M)$ and McN-A-343 $(10^{-4}\;M)$, although it alone has weak effect on CA secretion. However, it did not affect the CA secretion evoked by excess $K^+\;(5.6{\times}10^{-2}\;M)$. Leptin alone produced a weak secretory response of the CA. Moreover, leptin (10 ng/ml) in to an adrenal vein for 60 min also augmented the CA release evoked by BAY-K-8644, an activator of the dihydropyridine L-type $Ca^{2+}$ channels, and cyclopiazonic acid, an inhibitor of cytoplasmic $Ca^{2+}$ ATPase. However, in the presence of U0126 $(1\;{\mu}M)$, an inhibitor of mitogen-activated protein kinase (MAPK), leptin no longer enhanced the CA secretion evoked by ACh and DMPP. Furthermore, in the presence of anti-leptin (10 ng/ml), an antagonist of Ob receptor, leptin (10 ng/ml) also no longer potentiated the CA secretory responses evoked by DMPP and Bay-K-8644. Collectively, these experimental results suggest that leptin enhances the CA secretion from the rat adrenal medulla evoked by cholinergic stimulation (both nicotininc and muscarinic receptors), but does not that by membrane depolarization. It seems that this enhanced effect of leptin may be mediated by activation of U0126-sensitive MAPK through the leptin receptors, which is probably relevant to the activation of the dihydropyridine L-type $Ca^{2+}$ channels located on the rat adrenomedullary chromaffin cells.

• Nutritional Sciences
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• v.6 no.2
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• pp.73-77
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• 2003

PAI-1 (plasminogen activator inhibitor-1), leptin, and resistin are synthesized and secreted by Int cells of rodents and have recently been postulated to be an important link to obesity. This study was conducted to identify the nutritional regulation of PAI-1, leptin, and resistin gene expression in 0b/ob mice. The mice were divided into four groups according to nutritional status: control, 48 hour fasting, 48 hour-fasting/12 hour-refeeding, and 48 hour-fasting/24 hour-refeeding. The mRNA levels of each peptide were measured by semi-quantitative RT-PCR. In visceral fat tissue, the level of PAI-1 mRNA increased markedly when 48h-fasted animals were refed with a high carbohydrate-low fat diet. However, lasting/refeeding did not appreciably change PAI-1 mRNA levels in subcutaneous fat tissue. Similar results were obtained for resistin mRNA levels in both types of fat tissues. These findings suggest that visceral adipose tissue might be more sensitively involved in the nutritional regulation of PAI-1 and resistin gene expression compared to subcutaneous fat tissue. The level of leptin mRNA decreased markedly in the 48h-fasted animals, and increased markedly when 48h-fasted animals were refed with a high carbohydrate-low fat diet. The nutritional regulation of leptin mRNA showed similar patterns in both types of fat tissues. In conclusion, the nutritional regulation of gene expression encoding PAI-1, resistin, and leptin from adipocytes may vary according to the type of adipose tissue.

• Journal of Nutrition and Health
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• v.39 no.4
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• pp.323-330
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• 2006

Peripheral insulin resistance in obese/type II diabetes animals results from an impairment of insulin-stimulated glucose uptake into skeletal muscle. Insulin stimulate the translocation of GLUT4 from intracellular location to the plasma membrane. Soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) is implicated in mediation of fusion of GLUT4-containing vesicle with the plasma membrane. Present study investigated regulatory effects of Rhodiola sachalinensis administration and exercise training on the expression of GLUT4 protein and SNAREs protein in skeletal muscles of obese Zucker rats. Experimental animals were randomly assigned into one of five groups ; lean control(LN), obese control(OB), exercise-treated(EXE), Rhodiola sachalinensis-treated(Rho), combine of Rho & EXE (Rho-EXE). All animals of exercise training (EXE, Rho-EXE) performed treadmill running for 8 weeks, and animals of Rho groups (Rho, Rho-EXE) were dosed daily by gastric gavage during the same period. After experiment, blood were taken for analyses of glucose, insulin, and lipids levels. Mitochondrial oxidative enzyme (citrate synthase, CS ; $\beta$-hydroxyacyl-CoA dehydrogenase, $\beta$-HAD) activity were analysed. Skeletal muscles were dissected out for analyses of proteins (GLUT4, VAMP2, syntaxin4, SNAP23). Results are as follows. Exercise and/or Rhodiola sachalinensis administration significantly reduced body weight and improved blood lipids (TG, FFA), and increased insulin sensitivity. Endurance exercise significantly increased the activity of mitochondrial enzymes and the expression of GLUT4 protein, however, administration of Rhodiola sachalinensis did not affect them. The effect of exercise and/or Rhodiola sachalinensis administration on the expression of SNARE proteins was unclear. Our study suggested that improvement insulin sensitivity by exercise and/or Rhodiola sachalinensis administration in obese Zucker rats is independent of expression of SNARE proteins.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.553-556
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• 2004

Spatial and temporal aspects of toxic dinoflagellate Cochlodinium.p blooms and consequences of physical features in complex coastal ecosystems, off the southern Korean coast, have been investigated using data obtained from SeaWiFS and AVHRR as well as in-situ observations. Hydrographic parameters measured using CTD sensors were used to elucidate physical factors affecting the spatial distribution and abundance of Cochlodinium.p blooms. The results show spatial and temporal variations of chlorophyll-a (Chl-a) and sea surface temperature (SST) and reveal significant information about Cochlodinium.p blooms and process underlying their evolution. Satellitederived Chl-a estimates appear to be potential in explicating the evolution, movement and distribution of Cochlodinium.p blooms in the enclosed bays of the South Sea. The existence of thromohaline waters offshore provide favorable conditions for the rapid growth and subsequent southward initiation of Cochlodinium.p blooms that are influenced to flow on the offshore branch (OB) during September. It was observed that there was a significant variation in the sun-induced chlorophyll-a fluorescence signal in the remote sensing fluorescence spectra and its high-intensity was recognized during the period of exponential growth and physical transport. Satellite-derived Chl-a concentration during September 1999 ranged between $3­60mg/m^3$ inside the Jin-hae and adjacent Bays and $1-6mg/m^3$ in offshore waters, with varying Cochlodinium.p abundances 1500 to 26000 cells $ml^{-1}.$ The closely spaced CTD surveys and satellite-derived SST give a complete overview on the initiation of Cochlodinium.p blooms in hydrodynamically active regions of the offshore southern East Sea by the influence of Tsushima Warm Current (TWC).

• Nuclear Engineering and Technology
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• v.19 no.4
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• pp.317-324
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• 1987

The purpose of this work is to present a spatial neutron kinetics computational scheme for the analysis of space-dependent transients like rod ejection accident of pressurized water reactors. In this work modified Borresen's 1.5 group coarse mesh scheme was formulated for the neutronic computation of the space-dependent transients and applied to the analysis of hypothetical rod ejection accident of KNU no. 1 PWR core at BOC, HZP. The computational accuracy of the modified Borresen's scheme is examined by comparing calculations for core power and control rod worths with startup core physics test results. Effects of such parameters as ejected rod worths and number of delayed neution group ell transient results as well as computational efficiency are also examined. OB this basis it is suggested that the modified Borresen's method is a useful scheme for the analysis of spatial neutron transients of PWR's.