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Quantitative visualization of Taylor-Couette flow with helical protrusion using optical and ultrasound imaging method

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排灌机械工程学报 2016年第10期34卷 829-834页

作者： kim S.j. TU X.C. kim H.B. School of Mechanical and Aerospace Engineering Gyeongsang National University Research Center for Aircraft Parts Technology Gyeongsang National University

The simplified flow of drilling process in the soil hardening or oil rig site was experimentally investigated. Two flow models were used. One is the concentric cylinders with helical protrusion at the inner cylinder. The other is the concentric plain wall cylinders with axial flow. The radius ratio and aspect ratio of both models are the same with 0. 65 and 48,respectively. The mud is the typical fluid seen in the soil hardening processes. We used the water and the mud for the working fluid. We used the optical PIV for the water flow measurement and echo PIV for the mud flow. In case of the water study,the dominant vortical structures appeared in both the protrusion and plain model with axial *** case of mud flow,the vortices shown in the water model disappeared and the push and pull-up motion by the protrusion is dominant. We believe this information can be useful to understand the flow physics of drilling process in the complex fluid flow.

关键词： Taylor-Couette flow surface protrusion echo PIV mud flow

Expression of apoptosis-related factors in chronic cyclosporine nephrotoxicity after cyclosporine withdrawal

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Acta Pharmacologica Sinica 2004年第4期25卷 3-13页

作者： Sun-woo Lim,Bo-kyung SUN,Bum-soon CHOI,Sylvia GLOWACKA,Alison j COX,Darren j KELLY,Yong-soo kim,jin kim,Byung-kee BANG,Chul-woo YANG Departments of Internal Medicine the Catholic University of Korea Seoul137-040 Korea Departments of Internal Medicine the Catholic University of Korea Seoul137-040 Korea Departments of Internal Medicine the Catholic University of Korea Seoul137-040 Korea Department of Medicine St Vincent’s Hospital Fitzroy University of Melbourne Australia Department of Medicine St Vincent’s Hospital Fitzroy University of Melbourne Australia Department of Medicine St Vincent’s Hospital Fitzroy University of Melbourne Australia Departments of Internal Medicine the Catholic University of Korea Seoul137-040 Korea Departments of Anatomy the Catholic University of Korea Seoul137-040 Korea Departments of Internal Medicine the Catholic University of Korea Seoul137-040 Korea Departments of Internal Medicine the Catholic University of Korea Seoul137-040 Korea MD PhD

Aim: To examine whether the reversibility of chronic cyclosporine A (CsA) nephrotoxicity is associated with apoptotic cell death and its regulatory factors. METHODS: Chronic CsA nephrotoxicity was induced in Sprague- Dawley rats by administering CsA (15 mg/kg, sc) for 5 weeks, and then withdrawing it for 5 or 10 weeks. The effect of CsA withdrawal on apoptotic cell death was evaluated by an in situ TdT-mediated deoxyuridine triphos- phate-biotin nick end-labeling (TUNEL) assay and the expression of pro-apoptotic [(transforming growth factor- beta1 (TGF-β1) and Fas] and anti-apoptotic [epidermal growth factors (EGF) and Bcl-2] factors. RESULTS: Discontinuation of CsA induced significant decreases in TUNEL-positive cells in a time-dependent manner and the reduction in TUNEL-positive cells was correlated with the tubulointerstitial fibrosis score (r=0.919, P<0.01). Upregulation of TGF-β1 and Fas expression in CsA-treated rat kidneys was decreased significantly after with- drawal of CsA. In contrast, downregulated EGF and Bcl-2 expression returned to normal or supernormal levels. CONCLUSION: CsA withdrawal is associated with a decrease in apoptotic cell death and with changes in the expression of pro-apoptotic and anti-apoptotic molecules involved in renal wound repair. This may constitute one of the mechanisms underlying the reversibility of chronic CsA nephrotoxicity.

关键词： cyclosporine apoptosis bcl-2 fas epidermal growth factor transforming growth factor-beta fibrosis

Regenerative potential of targeting glycogen synthase kinase-3 signaling in neural tissues

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Neural Regeneration Research 2015年第12期10卷 1912-1913页

作者： Eui-Man jung jeffrey j.Moffat Woo-Yang kim Department of Developmental Neuroscience Munroe-Meyer InstituteUniversity of Nebraska Medical Center

Multiple roles of glycogen synthase kinase-3（GSK-3）in neural tissues：GSK-3 is a serine/threonine kinase that has two isoforms encoded by two different genes,GSK-3αand GSK-3β,in ***-3 has several sites of serine a... 详细信息

关键词： GSK Regenerative potential of targeting glycogen synthase kinase-3 signaling in neural tissues

Denitrification Rates and Their Controlling Factors in Streams of the Han River Basin with Different Land-Use Patterns

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Pedosphere 2014年第4期24卷 516-528页

作者： S.P.jUNG Y.j.kim H.KANG School of Civil and Environmental Engineering Yonsei UniversitySeoul 120-749(Korea) River and Coastal Research Division Korea Institute of Construction TechnologyGoyang 211-712(Korea)

Land-use patterns can affect various nutrient cycles in stream ecosystems, but little information is available about the effects of urban development on denitrification processes at the watershed scale. In the presented study, we investigated the controlling factors of denitrification rates within the streams of the Han River Basin, Korea, with different land-use patterns, in order to enhance the effectiveness of water resource management strategies. Ten watersheds were classified into three land-use patterns （forest, agriculture and urban） using satellite images and geographic information system techniques, and in-situ denitrification rates were determined using an acetylene blocking method. Additionally, sediment samples were collected from each stream to analyze denitrifier communities and abundance using molecular approaches. In-situ denitrification rates were found to be in the order of agricultural streams （289.6 mg N20-N m-2 d-1）〉 urban streams （157.0 mg N20-N m-2 d-1）〉 forested streams （41.9 mg N20-N m-2 d-l）. In contrast, the average quantity of denitrifying genes was the lowest in the urban streams. Genetic diversity of denitrifying genes was not affected by watershed land-use pattern, but exhibited stream-dependent pattern. More significance factors were involved in denitrification in the sites with higher denitrification rates. Multiple linear regression analysis revealed that clay, dissolved organic carbon and water contents were the main factors controlling denitrification rate in the agricultural streams, while dissolved organic carbon was the main controlling factor in the urban streams. In contrast, temperature appeared to be the main controlling factor in the forested streams.

关键词： denitrifier communities denitrifying genes nutrient cycle stream ecosystem

Utilizing gastric cancer organoids to assess tumor biology and personalize medicine

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World journal of Gastrointestinal Oncology 2019年第7期11卷 509-517页

作者： Miranda Lin Mei Gao Michael j Cavnar joseph kim Department of Surgery University of Kentucky

While the incidence and mortality of gastric cancer (GC) have declined due to public health programs, it remains the third deadliest cancer worldwide. For patients with early disease, innovative endoscopic and complex surgical techniques have improved survival. However, for patients with advanced disease, there are limited treatment options and survival remains poor. Therefore, there is an urgent need for more effective therapies. Since novel therapies require extensive preclinical testing prior to human trials, it is important to identify methods to expedite this process. Traditional cancer models are restricted by the inability to accurately recapitulate the primary human tumor, exorbitant costs, and the requirement for extended periods of development time. An emerging in vitro model to study human disease is the patient-derived organoid, which is a three-dimensional system created from fresh surgical or biopsy tissues of a patient’s gastric tumor. Organoids are cultured in plastic wells and suspended in a gelatinous matrix, providing a substrate for extension and growth in all dimensions. They are rapid-growing and highly representative of the molecular landscape, histology, and morphology of the various subtypes of GC. Organoids uniquely model tumor initiation and growth, including steps taken by normal stomach cells to transform into invasive, intestinal-type tumor cells. Additionally, they provide ample material for biobanking and screening novel therapies. Lastly, organoids are a promising model for personalized therapy and warrant further investigation in drug sensitivity studies for GC patients.

关键词： Organoids Gastric cancer Cancer models Drug sensitivity Drug screening Personalized medicine

Remote ischemic conditioning: the brain’s endogenous defense against stroke

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Neural Regeneration Research 2020年第12期15卷 2249-2250页

作者： Caleb j.Heiberger Tej Mehta jae kim Divyajot SSANDhu University of South Dakota Sanford School of MedicineSioux FallsSDUSA

Introduction to ischemic conditioning:In 1986,Murray built upon a series of accumulated works to demonstrated that brief ischemic"training"episodes fortified cardiac tissue against impending prolonged infarction(Murry et al.,1986).This discovery altered the dogmatic understanding of ischemia,highlighting that time-dependent tissue compromise during infarction was bimodal,not linear,in *** of being invariably deleterious,an organ’s response to ischemia is dependent upon both the duration of the infarction as well as adaptions from previous,transient ischemic episodes.

关键词： endogenous ischemia conditioning

An Assessment of Eco Driving System for Agricultural Tractor

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journal of Agricultural Science and Technology(B) 2011年第6期1卷 906-912页

作者： S. H. Park Y. j. kim D. H. im C. K. kim National Academy of Agricultural Science Rural Development Administration Suwon 441857 Republic of Korea

In this study, tractor power output, fuel consumption rate and work performance were indirectly predicted in order to develop an eco driving system. Firstly, equations were developed which could foretell tractor power output and fuel consumption rate using characteristic curves of tractor power output. Secondly, with actual engine revolution per minute （rpm） determined by initial engine rpm and work load, tractor power output and fuel consumption rate were forecasted. Thirdly, it was possible to foresee tractor work performance and fuel consumption rate by the speed signals of Global Positioning System （GPS）. Lastly, precision of the eco driving system was evaluated through tractor Power Take-Off （PTO） test, and effects of the eco driving system were investigated in the plowing and rotary tilling operations. Engine rpm, power output, fuel consumption rate, work performance and fuel consumption rate per plot area were displayed on the eco driving system. Predicted tractor power outputs in the full load curve were well coincided with the actual power output of prototype, but small differences, 1 to 6 kW were found in the part load curve. Error of the fuel consumption rate was 0.5 to 3 L/h at the part load curve. It was shown that 69% and 53% of fuel consumption rates could be reduced in plowing and rotary tilling operations, respectively, when the eco driving system was installed in tractor.

关键词： Tractor fuel consumption rate Power Take-Off (PTO).

彼得·拉莫和循道宗的命名:拉莫式布道术以降的中世纪科学

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跨文化研究 2021年第2期 79-92,287页

作者：瓦尔特·昂格叶仁杰(译) 不详中国人民大学哲学院

"方法"与约翰·卫斯理所创建的新教教派"循道宗"(Meth-odism)之间的联系一直都是个谜题,甚至卫斯理本人也不清楚。卫斯理错误地认为这个词来自于早期的医学团体,指的是那些在日常生活中严格遵循规律的人。事实上,这个词最初指的是彼得... 详细信息

"方法"与约翰·卫斯理所创建的新教教派"循道宗"(Meth-odism)之间的联系一直都是个谜题,甚至卫斯理本人也不清楚。卫斯理错误地认为这个词来自于早期的医学团体,指的是那些在日常生活中严格遵循规律的人。事实上,这个词最初指的是彼得·拉莫的方法,属于纯粹的逻辑学,并能够应用于所有学科。拉莫推动了18世纪的"方法崇拜",但很多布道者仅仅是"口头尊崇"拉莫主义方法,以至于18世纪晚期的人不能理解"循道宗"的确切含义。笔者认为卫斯理虽然不知道这个词的来源,但远比其自以为的更接近"循道宗"的最初含义,因为其著作反映了拉莫的深远影响。

关键词：循道宗方法拉莫主义者逻辑学

Synthesis and mesomorphic properties of new Schiff base esters with different alkyl chains

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Chinese Chemical Letters 2009年第7期20卷 767-770页

作者： Sie Tiong Ha Lay Khoon ong Siew Teng ong Guan Yeow Yeap joanna Pik Wan Wong Teck Ming Koh Hong Cheu Lin Faculty ofEngineering & Science Universiti Tunku Abdul RahmanJln Genting KlangSetapak 53300 Kuala LumpurMalaysia Faculty of Engineering & Science Universiti Tunku Abdul RahmanJln Genting KlangSetapak 53300 Kuala LumpurMalaysia Liquid Crystal Research Laboratory School of Chemical SciencesUniversiti Sains Malaysia 11800 MindenPenangMalaysia Department of Chemistry University of YorkHeslingtonYork YO10 5DDUnited Kingdom.

A new series of Schiff base esters, 4-（dimethylamino）benzylidene-4＇-alkanoyloxyanilines containing even number of carbons at the end group of the molecules （Cn-1H2n-1COO, n = 6, 8, 10, 12, 14, 16, 18） were synthesized. The present compounds were monotropic liquid crystals. It was also found that the end groups of the molecules had effect on the mesomorphic properties. C 2009 Sie Tiong Ha. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Liquid crystals Schiff base esters Monotropic compounds Mesomorphic properties