• The Korean Journal of Physiology and Pharmacology
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• 제22권4호
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• pp.447-456
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• 2018

Angiotensin-(1-9) [Ang-(1-9)], generated from Ang I by Ang II converting enzyme 2, has been reported to have protective effects on cardiac and vascular remodeling. However, there is no report about the effect of Ang-(1-9) on pulmonary hypertension. The aim of the present study is to investigate whether Ang-(1-9) improves pulmonary vascular remodeling in monocrotaline (MCT)-induced pulmonary hypertensive rats. Sprague-Dawley rats received Ang-(1-9) ($576{\mu}g/kg/day$) or saline via osmotic mini-pumps for 3 weeks. Three days after implantation of osmotic mini-pumps, 50 mg/kg MCT or vehicle were subcutaneously injected. MCT caused increases in right ventricular weight and systolic pressure, which were reduced by co-administration of Ang-(1-9). Ang-(1-9) also attenuated endothelial damage and medial hypertrophy of pulmonary arterioles as well as pulmonary fibrosis induced by MCT. The protective effects of Ang-(1-9) against pulmonary hypertension were inhibited by Ang type 2 receptor ($AT_2R$) blocker, but not by Mas receptor blocker. Additionally, the levels of LDH and inflammatory cytokines, such as $TNF-{\alpha}$, MCP-1, $IL-1{\beta}$, and IL-6, in plasma were lower in Ang-(1-9) co-treated MCT group than in vehicle-treated MCT group. Changes in expressions of apoptosis-related proteins such as Bax, Bcl2, Caspase-3 and -9 in the lung tissue of MCT rats were attenuated by the treatment with Ang-(1-9). These results indicate that Ang-(1-9) improves MCT-induced pulmonary hypertension by decreasing apoptosis and inflammatory reaction via $AT_2R$.

• Archives of Plastic Surgery
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• 제44권4호
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• pp.324-331
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• 2017

Background Lipedema is a condition consisting of painful bilateral increases in subcutaneous fat and interstitial fluid in the limbs with secondary lymphedema and fibrosis during later stages. Combined decongestive therapy (CDT) is the standard of care in most countries. Since the introduction of tumescent technique, liposuction has been used as a surgical treatment option. The aim of this study was to determine the outcome of liposuction used as treatment for lipedema. Methods Twenty-five patients who received 72 liposuction procedures for the treatment of lipedema completed a standardized questionnaire. Lipedema-associated complaints and the need for CDT were assessed for the preoperative period and during 2 separate postoperative follow-ups using a visual analog scale and a composite CDT score. The mean follow-up times for the first postoperative follow-up and the second postoperative follow-up were 16 months and 37 months, respectively. Results Patients showed significant reductions in spontaneous pain, sensitivity to pressure, feeling of tension, bruising, cosmetic impairment, and general impairment to quality of life from the preoperative period to the first postoperative follow-up, and these results remained consistent until the second postoperative follow-up. A comparison of the preoperative period to the last postoperative follow-up, after 4 patients without full preoperative CDT were excluded from the analysis, indicated that the need for CDT was reduced significantly. An analysis of the different stages of the disease also indicated that better and more sustainable results could be achieved if patients were treated in earlier stages. Conclusions Liposuction is effective in the treatment of lipedema and leads to an improvement in quality of life and a decrease in the need for conservative therapy.

• Tribology and Lubricants
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• 제33권6호
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• pp.288-295
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• 2017

In order to improve the efficiency and reliability of the machine, the friction should be minimized. The most widely used method to minimize friction is to maintain the fluid lubrication state. However, we can reduce friction only up to a certain limit because of viscosity. As a result of several recent studies, surface texturing has significantly reduced the friction in highly sliding machine elements, such as mechanical seals and thrust bearings. Thus far, theoretical studies have mainly focused on isothermal/iso-viscous conditions and have not taken into account the heat generation, caused by high viscous shear, and the temperature conditions on the bearing surface. In this study, we investigate the effect of dimple depth and film-temperature boundary conditions on the thermohydrodynamic (THD) lubrication of textured parallel slider bearings. We analyzed the continuity equation, the Navier-Stokes equation, the energy equation, and the temperature-viscosity and temperature-density relations using a computational fluid dynamics (CFD) code, FLUENT. We compare the temperature and pressure distributions at various dimple depths. The increase in oil temperature caused by viscous shear was higher in the dimple than in the bearing outlet because of the action of the strong vortex generated in the dimple. The lubrication characteristics significantly change with variations in the dimple depths and film-temperature boundary conditions. We can use the current results as basic data for optimum surface texturing; however, further studies are required for various temperature boundary conditions.

• 한국임상수의학회지
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• 제26권2호
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• pp.160-165
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• 2009

4개월령 수컷 박서 개(체중: 9 Kg)가 심잡음과 운동불내성을 주요 증상으로 내원하였다. 진단검사를 통해 환자는 대동맥 판막하 협착에 이환된 것을 확인할 수 있었다. 협착된 부위의 압력구배는 120 mmHg(와류의 속도: 5.4 m/s)이상이었으며, 환자는 풍선 확장술을 통해 임상증상을 개선하였다. 환자는 시술 후 주기적으로 모니터링 하였으며 다른 임상증상은 관찰되지 않았다. 이는 우리나라에서 대동맥 판막하 협착증에 이환된 환자에게 풍선 확장술을 통해 임상증상을 경감시킨 최초의 증례이다.

• 한국소음진동공학회논문집
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• 제20권12호
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• pp.1128-1138
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• 2010

정밀 방진에서 전형적인 문제로 고하중으로 인한 저주파 공진 특성이 있다. 전자기 에어 스프징은 진동 제어 장치이자 능동형 방진 장치이다. 이 연구에서 전자기 에어 스프링은 반도체 생산을 위한 저주파 공진을 제거하는 것을 목적으로 한다. 능동형 방진 장치로 기계 및 전가 부분은 2.5톤의 하 중에 작동되도록 설계하였다. 전자기 스프링은 탄성 공압 챔버 내에 공기압을 이용하여 띄우고, 전자기 된 시스템에 의하면 공진 주파수 영역에서 제어 시간 및 최고 피크가 상당히 줄어들었고, 그 결과 피동형 시스템 상의 고유 진동에 의해 발생되는 공진을 피할 수 있음을 보였다.

• 대한한방내과학회지
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• 제27권4호
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• pp.811-821
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• 2006

Objectives : Diabetes is a disease in which the body does not produce or properly use insulin. Etiological studies of diabetes and its complications showed that oxidative stress might play a major role. Therefore, many methods have been tried to regulate oxygen free radicals for treating diabetes and its complications. Because Mori foliumhas been known to be effective for the treatment of diabetes, the methanol extract of Mori folium was tested for its effectiveness in reducing the oxidative stress induced by streptozotocin. Methods : The crushed Mori folium was extracted 3 times, each time with 3 volumes of methyl alcohol at $60^{\circ}C$ or 24 h. The extract was filtered and evaporated under reduced pressure using a rotary evaporator to yield 11.7 g. Mori folium extract was oral-administered to diabetic rats induced by streptozotocin at 100 mg per 1 kg of body weight for 20 days. The efficacy of the Mori foliumextract was examined with regard to the enzymatic pathways involved in oxygen free radical production and glutathione balance. Results : The effects of the Mori foliumin streptozotocin-induced diabetic rats with regards to body weight, blood glucose and insulin level, hepatic lipid peroxide level, hepatic glutathione level, hepatic glutathione S-transferase and glutathione peroxidase level, hepatic aldose reductase activity, and hepatic sorbitol dehydrogenase activity were shown to be good enough to cure and prevent diabetes and its complications. Conclusions : These results indicated that Mori folium might reduce oxidative stress in tissues and organs by regulating the production of oxygen free radicals. Especially Mori folium might prevent and cure diabetes and its complications by reducing oxidative stress in the ${\beta}-cells$ of the pancreas.

• Parasites, Hosts and Diseases
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• 제53권3호
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• pp.355-359
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• 2015

Hydatid disease imposing serious threat on human health and great loss in live-stock pastoralism remains a major public health problem in western China. To assess and monitor the effect of control program on transmission dynamics, we used the prevalence of cystic echinococcosis in slaughtered sheep at slaughterhouse as an indicator during the period of 2007 to 2013 in Emin County, Xinjiang Uygur Autonomous Region, China. The results showed a significant decline trend of prevalence in all age groups during the 7 years when the control program was implemented; particularly, the rate was reduced by 72% after first 3 years. Among the sheep slaughtered, the age distribution evidenced that the prevalence increased significantly as the sheep grew older. The baseline data indicated that the rate was 4.5% at the age <1, 6.7% at age 2~, and reached to the highest 17.9% at age ${\geq}4$ years. Earlier response to the intervention pressure was seen in the sheep at the younger age. Significant decline started from 2008 at the age <1, from 2009 at age of 1~, 2010 at 2~ to 3~, and the latest, in 2012 at age ${\geq}4$. This study demonstrated that the prevalence of cystic echinococcosis in slaughtered sheep may be used as an indicator to assess and monitor the transmission status during and after control program providing information for betterment of performance to sustain control strength.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.2
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• pp.215-225
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• 2006

Today's requirements for print-press runnability and print quality demand an optimised absorption and adhesion of printing ink on the paper surface. Modern coating concepts for high glossing offset grades use ultra fine pigments, whereas binder level has continuously been decreased to a minimum in recent years to achieve the highest possible sheet gloss development and for economical reasons. Both the ultra fine pigments and the reduced binder levels lead in many cases to a faster ink setting rate. On the other hand, matt paper grades use relatively coarse pigments leading to a slow ink setting compared to the high glossing papers. Both too fast and too slow ink setting properties implicate drawbacks in print quality and print press runnability. The mechanisms behind the interactions between ink and coating have been presented in many previous publications. The purpose of this study was to determine and quantify how the ink setting rate is influenced by pigment system (GCC and GCC/clay blends), latex level and latex properties in the topcoat of double coated sheet fed offset paper. The roles of binder level and type in the precoat were also assessed. The effect of calendering (temperature and pressure) was studied with one formulation. The resulting ink setting characteristics were tested using three different laboratory testing instruments. The correlation amongst the different laboratory testing methods is discussed. The results show that by varying the latex properties, the pigment system and/or latex addition level, the ink tack development of ink applied to a topcoat pigment system can be significantly influenced. It can be slowed down as often desired with ultra fine pigments or speeded up in the case of coarse pigments. There was no visible effect on the ink setting rate by using different binder systems in the precoat..

• 대한기계학회논문집B
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• 제41권9호
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• pp.587-595
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• 2017

최근 들어 공조기가 슬림화 되고 따라서 열교환기의 깊이를 줄일 필요가 있다. 본 연구에서는 슬림형 알루미늄 열교환기에 적절한 루버 핀 형상을 도출하였다. 또한 도출된 루버 핀이 적용된 알루미늄 열교환기 시료를 제작하고 성능 시험을 수행하였다. 비교를 위하여 기존 열교환기에 대해서도 실험을 수행하였다. 도출된 형상의 핀 깊이($F_d$)는 10.0 mm, 루버 핏치($L_p$)는 0.9 mm, 루버 각(${\theta}$)은 $35^{\circ}$이다. 기존 시료에 비하여 신규 슬림 시료의 j 인자는 36%, f 인자는 2.3% 크게 나타났다. 따라서 열교환기 체적은 슬림 시료에서 26% 줄어들게 된다. 또한 동일 소비 동력에서의 전열량을 의미하는 $j/f^{1/3}$은 슬림 시료에서 55% 크다. 실험 데이터를 기존 상관식의 예측치와 비교하였다.

• 한국초지조사료학회지
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• 제17권1호
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• pp.43-50
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• 1997

The aim of the study is to describe the fate and transformation of nitrogen in grassland ecosystems. Field experiments were conducted using sandyloam soil under variabling conditions: Zen, fertilization, reduced slurry application(l20kg N $ha^{-1}\;yr^{-1}$), usual sluny application (240 kg N $ha^{-1}\;yr^{-1}$).Soil water samples were gathered with 120cm ceramic cups with initial pressure of 0.5 bar. Samples were collected twice a month and analysed for NO, colormetrically. Percolation was calculated as the difference between precipitation and potential evapotranspiration, and leaching as the product of percolation and nitrate content of the water h m the ceramic cups. The N$H_4$-N content in soil had no significant effect on slurry application, but high slurry application on grassland resulted in high N$O_3$-N content in soil. The NO, concentration in soil water was remarkably variable during the year. The average N$O_3$, concentration during experiment became the lowest(8.5 mg/e ) without slurry application and highest with 240kOa cattle sluny(25.3 mg4 ). For each of the three different amounts of cattle sluny applied (0, 120, and 240kOa), the amount of N$O_3$-N leached per year were 12, 23 and 29kg/ha respectively. On grassland under the climatic conditions of Allgau showed enormous nitrate leaching, which has a p a t potential of polluting the ground water. The high pool of mineral N in the soil are the source for N$O_3$ leaching. The leaching of N$O_3$ cannot be avoided completely, but minimized by optimizing N fertilization rate.