• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.4
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• pp.130-136
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• 2011

This study describes the effect of EGR rate on the combustion and emissions characteristics of a four cylinder CRDI diesel engine using biodiesel (soybean oil) blended diesel fuel. The test fuel is composed of 30% biodiesel and 70% ULSD (ultra low sulfur diesel) by volumetric ratio. The experiment of engine emissions and performance characteristics were performed under the various EGR rates. The experimental results showed that ignition delay was extended, the maximum combustion pressure and heat release gradually were decreased with increasing EGR rate. Comparing biodiesel blended fuel to ULSD, the injection quantity of biodiesel blended fuel was further increased than ULSD. The emission results showed that $NO_x$ emission of biodiesel blended fuel becomes higher according to the increase of EGR rate. However, in the case of biodiesel blended fuel, HC, CO and soot emissions were decreased compared to ULSD.

• Journal of Animal Science and Technology
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• v.47 no.3
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• pp.439-446
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• 2005

This study was conducted to elucidate the influence of recombinant bovine somatotropin (rBST) on the plasma IGF-I profiles in deer stags. Slow release rBST (250mg each) preparations were injected subcutaneously during the antler's non-growing period and growing period. It was observed that significant increases in the plasma IGF-I concentrations were occurred right after injections of the rBST irrespective of antler's non-growing period or growing period. When the rBST preparations were injected two times with one week interval during the antler's non-growing period, the mean level of IGF-I was found to be 2,920.7ng I mL, indicating that the IGF-I concentration increased up to 8.4-folds compared with a control. After two weeks from second shot, however, the IGF-I levels decreased to the level of the control. Similar results were also obtained with both a Sika and a Red deer during the antler's growing period. Increases in the IGF-I level of up to 5.6-folds with the Sika deer and 4.3-folds with the Red deer were found. Based on the present study, it is likely that the rBST may be used as a possible candidate for an antler's growth stimulating agent.

• The Korean Journal of Food And Nutrition
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• v.30 no.6
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• pp.1279-1285
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• 2017

$Amyloid-{\beta}$ protein ($A{\beta}$) is known to increase free radical production in neuronal cells, leading to cell death by oxidative stress. The purpose of this study was to evaluate the protective effects of $PineXol^{(R)}$ on $A{\beta}_{25-35}$ induced neuronal cell death. Rat pheochromocytoma (PC-12) cells were pre-treated with $100{\mu}g/mL$ of $PineXol^{(R)}$ for 2 h. The cells were exposed to single dose of $30{\mu}M$ $A{\beta}_{25-35}$ for 24 h. Cell death was assessed by a cell count kit-8 (CCK-8) assay, lactate and dehydrogenase (LDH) release assay. An Apoptotic process was analyzed by a protein expression of the Bcl-2 family using western blotting. Cell viability increased in PC-12 cells treated with both $A{\beta}_{25-35}$ and $PineXol^{(R)}$, compared to the control group. $PineXol^{(R)}$ induced a decrease of the Bcl-2 protein expression (p<0.05), while Bax and Sod1 increased (p<0.05), indicating attenuation of $A{\beta}_{25-35}$ induced apoptosis. These results suggest that $PineXol^{(R)}$ may be a good candidate for the prevention of Alzheimer's disease(AD).

• Journal of Trauma and Injury
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• v.33 no.1
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• pp.38-42
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• 2020

Purpose: Immediate post-laparotomy hypotension (PLH) is a precipitous drop in blood pressure caused by a sudden release of abdominal tamponade after laparotomy in cases of severe hemoperitoneum. The effect of laparotomy on blood pressure in patients with significant hemoperitoneum is unknown. Methods: In total, 163 patients underwent laparotomy for trauma from January 1, 2013 to December 31, 2015. Exclusion criteria included the following: negative laparotomy, only a hollow viscous injury, and hemoperitoneum <1,000 mL. After applying those criteria, 62 patients were enrolled in this retrospective review. PLH was defined as a decrease in the mean arterial pressure (MAP) ≥10 mmHg within 10 minutes after laparotomy. Results: The mean estimated hemoperitoneum was 3,516 mL. The incidence of PLH was 23% (14 of 62 patients). The MAP did not show significant differences before and after laparotomy (5 minutes post-laparotomy, 67.5±16.5 vs. 68.3±18.8 mmHg; p=0.7; 10 minutes post-laparotomy, 67.5±16.5 vs. 70.4±18.8 mmHg; p=0.193). The overall in-hospital mortality was 24% (15 of 62 patients). Mortality was not significantly higher in the PLH group (two of 14 [14.3%] vs. 13 of 48 [27.1%]; p=0.33). No statistically significant between-group differences were observed in the intensive care unit and hospital stay. Conclusions: PLH may be less frequent and less devastating than it is often considered. Surgical hemostasis during laparotomy is important. Laparotomy with adequate resuscitation may explain the equivalent outcomes in the two groups.

• Journal of Korean Society of Water and Wastewater
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• v.26 no.6
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• pp.889-896
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• 2012

In this study, simulation results of nitrogen and phosphorus removals and microbial activities for an $A_2O$ process in wastewater treatment plant are presented by using Activated Sludge Models (ASMs). Simulations were performed using pre-calibrated model and layout implemented in GPS-X simulation software. The models were used to investigate variations of SRT, water temperature, DO and C/N ratio effect on nutrients removal and microbial activity. According to the simulated results, the successful nitrification required SRT higher than 10.3 days, whereas increase of $NO_3$-N loading in the anaerobic reactor caused phosphorus release by PAOs; the effluent $NH_4$-N showed rapid change between $12^{\circ}C$(21.7 mg/L) and $13^{\circ}C$(3.2 mg/L); the effluent phosphorus was increased up to 1.9 mg/L at water temperature of $25^{\circ}C$; the DO increase was positive for heterotrophs and autotrophs growths but negative for PAOs growth; the PAOs showed low activity when C/N ratio was lower than 2.5. The experimental results indicated that the calibrated models can assure the prediction quality of the ASMs and can be used to optimize the $A_2O$ process.

• Korean Journal of Materials Research
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• v.20 no.4
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• pp.204-209
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• 2010

Recent high efficiency electronic devices have been found to have heat emission problems. As for LEDs, an excessive increase in the device temperature causes a drop of the luminous efficiency and circuit lifetime. Therefore, heat release in the limited space of such electronic parts is very important. This is a study of the possibility of using a coating of carbon materials as a solution for the thermal emission problem of electronic devices. Powdered carbon materials, cokes, carbon blacks, amorphous graphite, and natural flakes were coated with an organic binder on an aluminum sheet and the subsequent thermal emissivity was measured with an FT-IR spectrometer and was found to be in the range of $5{\sim}20\;{\mu}m$ at $50^{\circ}C$. The emissivity of the carbon materials coated on the aluminum sheet was shown to be over 0.8 and varied according to carbon type. The maximum thermal emissivity on the carbon black coated-aluminum surface was shown to be 0.877. The emissivity of the anodized aluminum sheets that were used as heat releasing materials of the electronic parts was reported to be in the range of 0.7~0.8. Therefore, the use of a coating of carbon material can be a potential solution that facillitates heat dissipation for electronic parts.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.14 no.1
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• pp.117-128
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• 2001

Gamiseunggal-tang(G-tang) has long been used for the treatment of acute and chronic allergic diseases(especially, urticaria) in oriental medicine. But, It's mechanism of action is not well investigated. Anal therapy is another way of taking medicine, which is not used in common situation but available for the treatment of colon and anal diseases. It is also used in GI tract diseases, Gynecological diseases, and pediatric diseases and so on. It is especially benefitable for patients who are in such situations as coma, severe vomiting, and swallowing difficulty. In this study, the author investigated the effects of G-tang by anal therapy on acute and chronic allergic reactions in murine model. The results obtained are as follows: 1. G-tang(0.01, 0.1 g/kg) inhibited the compound 48/80-induced ear swelling response in mice. Inhibitory effects of G-tang was significant (P<0.05) at the dose of 0.01 g/kg. 2. G-tang(0.001-0.1 g/kg) inhibited the cutaneous allergic reaction activated by anti-dinitrophenyl(DNP) IgE in rats. Especially, G-tang 0.01, 0.1 g/kg inhibited the cutaneous allergic reaction significantly. 3. G-tang(0.01-1 g/L) dose-dependently inhibited the compound 48/80-induced histamine release from the peritoneal mast cells. 4. G-tang(0.001-0.1 g/L) had a inhibitory effect on anti-DNP IgE-induced tumor necrosis factor-${\alpha}$ production. Above results indicate that anal therapy of G-tang may be beneficial in the treatment of acute and chronic allergic diseases.

• The Journal of Internal Korean Medicine
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• v.21 no.5
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• pp.819-827
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• 2000

Purpose : To investigate the inhibitory effect of HCE on platelet aggragation and erythrocyte deformiability, we performed following experiments. Methods : Concentrated Hyulbuchukotang (HCE) was fed to rats for 10days. We compare normal group with $500{\beta}{\Sigma}/{\beta}{\Sigma}$-high dose group and $100{\beta}{\Sigma}/{\beta}{\Pi}$-low dose group. Results : HCE enhanced the blood filtration rate, erythrocyte deformiability, reduced the platelet aggreablilty and inhibited granule release from collagen stimulated platelet, the prostaglandin synthesis in platelat. Conclusion : HCE should inhibit thrombos formation due to platelet hyperaggraeability and reduction of erythrocyte defonmiability.

• The Journal of Internal Korean Medicine
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• v.21 no.5
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• pp.829-837
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• 2000

Purpose : To investigate the inhibitory effect of BHE on platelet aggregation and erythrocyte deformability, we performed following experiments. Methods : Concentrated Boyanghwanotang (BHE) was fed to rats for 10days. High dose group was treated with $500{\beta}{\partial}/kg$ and low dose group with $500{\beta}{\partial}/kg$. Results : BHE enhanced the blood filtration rate, reduced the platelet aggregability, inhibited granule release from collagen-stimulated platelet, the prostaglandin syn-thesis in platelet and enhanced erythrocyte deformability. Conclusion : BHE should inhibit thrombos formation due to platlete hyperaggregabili-ty and reduction of erythrocyte deformabi-lity.

• Magazine of the Korea Concrete Institute
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• v.6 no.1
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• pp.89-100
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• 1994

The current test procedure for transfer length, which determine transfer length by measuring concrete strain, has an actual bond stress state in the prestressed pretensioned member : however, it is difficult to determine the bond properties of maximum bond stress and bond stiffness with this method. It is also difficult for design engineer to understand and select a correct safety criterion from the widely distributed results of such a ransfer test alone. An alternative testing procedure is provided here to determine the bond properties without measuring the concrete strain. In this test the bond stress is measured directly by creating a similar boundary condition within the transfer length in a real beam during the transfer of prestressing force. The prestressing force was released step by step by step from the unloading side. The release of force induces a swelling of the strand at the unloading side of concrete block, bonding force in the block, and a bond slip of the strand toward the other side of the block. Two center-hole load cells are used to record the end loads until the point of general bond slip(maximum bond stress). It is suggested that this test procedure be performed with the ordinary transfer test when determining the transfer length in a prestressed, pretensioned concrete beam.