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Experimental study on spray cooling under reduced pressures

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Science China(Technological Sciences) 2019年第2期62卷 349-355页

作者： PENG Can XU XiangHua li ye ming li YuLong liANG XinGang Key Laboratory for Thermal Science and Power Engineering of Ministry of Education School of Aerospace Engineering Tsinghua University School of Energy and Power Engineering Beihang University

Spay cooling is a complicated flow and heat transfer process affected by multi-factors among which the environmental pressure is extremely important. However the influence of pressure is not investigated sufficiently, especially the reduced pressure. In the present study, spray cooling under low initial environmental partial pressures and vapor partial pressures with R21 are investigated with a closed spray and condensation system. To study the influence of initial environmental partial pressure, different amounts of nitrogen are inflated into the vacuum flash chamber, while the vapor partial pressure is kept constant. To study the influence of vapor partial pressure, a cascade refrigerator is used to condense the vapor with different condensation temperatures so that the vapor partial pressure can be maintained or adjusted, while the initial environmental partial pressure is kept *** experimental results show that the spray cooling power increases monotonically with the increasing spray flow rate in the experimental range, while the cooling efficiency decreases with the increasing spray flow rate. The spray cooling power and cooling efficiency vary with the initial environmental partial pressure or the vapor partial pressure non-monotonously, which indicates there is an optimal pressure for the heat transfer performance. Besides, the mechanism of the non-monotonous variation trend is discussed based on the key aspects including flash evaporation, convection and boiling. Especially, the boiling heat transfer curve is applied to explain the trend.

关键词： spray cooling flash evaporation reduced pressure phase change

A new C_(27)-steroidal glycoside from Ophiopogon japonicus

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Chinese Chemical Letters 2008年第1期19卷 82-84页

作者： Jian Zhong Wang li ming ye Xiao Bing Chen West China College of Pharmacy Sichuan University Chengdu 610041 China

A new C27-steroidal glycoside with three known compounds were isolated from the tuber of Ophiopogonjaponicus （Thunb.） Ker-Gawl. Based on the spectral analysis, including HRMS, 1H NMR, 13C NMR, DEPT, 1H-1H COSY, HMQC and HMBC, their chemical structures were determined as pennogenin-3-O-α-L-rhamnopyranosyl-（1→ 2）-β-D-xylopyranosyl-（1→ 4）-13-D-gluco- pyranoside （1）, pennogenin-3-O-α-L-rhamnopyranosyl-（1→ 2）-β-D-glucopyranoside （2）, ophiopojaponin C （3） and ophiopogonin D （4）. 2007 Jian Zhong Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Ophiopogon japonicus C27-steroidal glycoside

基于冠状动脉CT的FFR在冠心病患者临床诊断中对诊断灵敏度及特异度的影响研究

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影像技术 2024年第2期36卷 9-12,19页

作者：徐天佩江永尧李叶明东莞市第八人民医院(东莞市儿童医院)放射科广东523000

目的:分析基于冠状动脉CT的血流储备分数(FFR)在冠心病患者临床诊断中对诊断灵敏度及特异度的影响。方法:此次研究总共纳入48例研究对象,均是2020年12月-2022年12月到我院诊治的疑似冠心病患者,均接受冠状动脉造影检查(CAG)、冠脉CT造... 详细信息

目的:分析基于冠状动脉CT的血流储备分数(FFR)在冠心病患者临床诊断中对诊断灵敏度及特异度的影响。方法:此次研究总共纳入48例研究对象,均是2020年12月-2022年12月到我院诊治的疑似冠心病患者,均接受冠状动脉造影检查(CAG)、冠脉CT造影检查(CCTA)下测定FFR值检查。将CAG作为参照标准,统计CCTA下测定FFR值的诊断效能。结果:将CAG作为参照标准,48例疑似冠心病患者经CT-FFR检查后,真阳38例,假阳1例,真阴5例,假阴4例。CT-FFR诊断冠心病的敏感度为90.48%(38/42),特异度为83.33%(5/6),准确率为89.58%(43/48)。在冠心病检出率上,CT-FFR检查低于CAG检查,对比差异有统计学意义(P<0.05)。结论:CT冠脉造影下测定FFR值用于冠心病的临床诊断效果良好,诊断敏感度与特异度较高,可作为临床诊断冠心病的辅助手段,临床可进一步推广应用。

关键词：冠心病基于冠状动脉CT的FFR 灵敏度特异度

Anti-diabetic effects of cinnamaldehyde and berberine and their impacts on retinol-binding protein 4 expression in rats with type 2 diabetes mellitus

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Chinese Medical Journal 2008年第21期121卷 2124-2128页

作者： ZHANG Wei XU Yan-cheng GUO Fang-jian MENG ye li ming-li Department of Endocrinology Zhongnan Hospital ot Wunan University Wuhan Hubei 430071 China

Background Retinol binding protein 4 （RBP4）, as an adipocyte secreted cytokine, was recently found to be inversely correlated with expression of glucose transporter 4 （GLUT4） in insulin resistance （IR） state and to have an intimate relationship with IR and type 2 diabetes mellitus （T2DM）. The present study aimed to evaluate the anti-diabetic efficacy of cinnamaldehyde （Cin）, berberine （Ber）, and metformin （Met） as well as their impacts on the RBP4-GLUT4 system. Methods Rat models of T2DM were established by combination of intraperitoneal injection of low-dose streptozotocin and high fat diet induction. Rats were divided into five groups： the control group, the diabetes group, the diabetes＋Ber group, the diabetes＋Cin group, and the diabetes＋Met group. Western blotting was used to detect the serum or tissue RBP4 and GLUT4 protein levels. Results After treatment for four weeks, both Cin and Ber displayed significant hypolipidemic, hypoglycemic, and insulin sensitizing functions （P 〈0.01） compared with the control group. Their effects on lowering fasting plasma glucose （FPG）, low density lipoprotein-cholesterol （LDL-C） and homeostasis model assessment of insulin resistance （HOMA-IR） seem even better than that of Met. Cin and Ber markedly lowered serum RBP4 levels and up-regulated the expression of tissue GLUT4 protein, and Cin seemed more notable in affecting these two proteins. Conclusions Both Cin and Ber display an exciting anti-diabetic efficacy in this study and may be of great value for the treatment of type 2 diabetes. Their mechanisms involve the RBP4-GLUT4 system, during which the serum RBP4 levels are lowered and the expression of tissue GLUT4 protein is up-regulated.

关键词： cinnamaldehyde berberine type 2 diabetes meUitus insulin resistance retinol binding protein 4 glucose transporter 4

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麻醉护理风险管理培训课程的构建

护理学报 2024年第14期31卷 33-37页

作者：姚呈高翔杨明莹何艳琳李明烨昆明医科大学第二附属医院麻醉手术科云南昆明650032 昆明医科大学第二附属医院护理部云南昆明650032

目的构建适合我国麻醉护理人员麻醉护理风险管理培训课程,为麻醉护理教育提供实践依据。方法以ADDIE教学模型为理论基础,结合文献分析、质性访谈拟定培训课程初稿,通过德尔菲法对26名专家进行2轮函询,根据咨询结果筛选、优化条目池,构... 详细信息

目的构建适合我国麻醉护理人员麻醉护理风险管理培训课程,为麻醉护理教育提供实践依据。方法以ADDIE教学模型为理论基础,结合文献分析、质性访谈拟定培训课程初稿,通过德尔菲法对26名专家进行2轮函询,根据咨询结果筛选、优化条目池,构建麻醉护理风险管理培训课程。结果2轮专家函询问卷回收率为73%、85%;专家权威系数为0.895、0.909;肯德尔和谐系数为0.347~0.497(P<0.001)、0.371~0.372(P<0.001);变异系数为0~0.30、0~0.18。最终形成麻醉护理风险管理培训课程,由29个条目组成。结论研究构建的麻醉护理风险管理培训课程较为可靠,且具有科学性,对麻醉护理风险培训具有参考意义。

关键词：麻醉护理风险管理课程构建

Use of arterial conduit for arterial revascularization during liver and multivisceral transplantation

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Chinese Medical Journal 2011年第19期124卷 2986-2989页

作者： MA Yi li Qiang ye Zhi-ming ZHU Xiao-feng HE Xiao-shun Organ Transplantation Center the First Affiliated Hospital Sun Yat-sen University Guangzhou Guangdong 510080 China

Background At present, revascularization is still one of the most critical technologies in orthotopic liver transplantation （OLT）. Hepatic artery （HA） variations occur frequently in both donors and recipients. Moreover, there are always some pathological changes in the recipient hepatic artery. If handled improperly, it may cause complications after ***, arterial conduit could be used in primary OLT, re-OLT and multiple-OLT. This study aimed to investigate the indications, methods and techniques with usage of arterial conduit for HA revascularization during adult *** We reviewed 1200 patients of consecutive OLTs performed during 2000-2009 in the First Affiliated Hospital of Sun Yat-sen University. Of these patients, 48 recipients with artery variations received HA revascularization with usage of arterial conduit and special postoperative managements. The indications, methods, techniques, and the managements of postoperative complications in adult OLT with usage of arterial conduit for HA revascularization were *** In 48 cases with artery bypass, the arterial conduit were anastomosed between donor hepatic artery and recipient infrarenal aorta （n=32）, between donor hepatic artery and recipient suprarenal aorta （n=10）, and between donor upper abdominal organ cluster artery and recipient suprarenal aorta （n=6）. The technique was applied in 4% （48/1200 cases） of the whole OLTs performed in the same period, and the patency rate of the conduits was 100%. Forty patients （83.3%） survived, and the average survival time was 3.9 years. Eight patients （16.7%） died （all due to tumor recurrence）,while the average survival time was 1.2 years. All these patients have not experienced artery-related complications in their survival *** When recipient HA has variations or pathological changes in OLT, the donor artery should be anastomosed to recipient abdominal aorta with an arterial conduit to achieve satisfactory outcomes. For arteri

关键词： liver transplantation hepatic artery iliac artery graft

The breakfast imperative： The changing context of global food security

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Journal of Integrative Agriculture 2016年第6期15卷 1179-1185页

作者： ye li-ming Jean-Paul Malingreau TANG Hua-jun Eric Van Ranst Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081P.R.China CAAS-UGent Joint Laboratory of Global Change and Food Security Beijing 100081P.R.China Department of Geology and Soil Science(WE13) Ghent University9000 GentBelgium Earth and life Institute Universite Catholique de Louvain1348 Louvain-la-NeuveBelgium

The debate on global food security has regained vigor since the food crisis of 2008, when a sudden spike in the prices of staple food commodities dramatically demonstrated that securing the supply and accessibility of food for a world of nine billion people in 2050 cannot be taken for grant- ed （Godfray etal. 2010; Swinnen and Squicciarini 2012;

关键词： The breakfast imperative The changing context of global food security

From statistics to grids:A two-level model to simulate crop pattern dynamics

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Journal of Integrative Agriculture 2022年第6期21卷 1786-1798页

作者： XIA Tian WU Wen-bin ZHOU Qing-bo Peter HVERBURG YANG Peng HU Qiong ye li-ming ZHU Xiao-juan Key Laboratory for Geographical Process Analysis&Simulation Hubei Province/College of Urban&Environmental ScienceCentral China Normal UniversityWuhan 430079P.R.China Key Laboratory of Agricultural Remote Sensing Ministry of Agriculture and Rural Affairs/Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081P.R.China Agricultural Information Institute Chinese Academy of Agricultural SciencesBeijing 100081P.R.China Institute for Environmental Studies VU University AmsterdamAmsterdam 1085The Netherlands Department of Geology Ghent UniversityGhent 9000Belgium Commercial and Economic Law School China University of Political Science and LawBeijing 100088P.R.China

Crop planting patterns are an important component of agricultural land *** patterns have been significantly changed due to the combined impacts of climatic changes and socioeconomic ***,the extent of these changes and their possible impacts on the environment,terrestrial landscapes and rural livelihoods are largely unknown due to the lack of spatially explicit datasets including crop planting *** fill this gap,this study proposes a new method for spatializing statistical data to generate multitemporal crop planting pattern *** method features a two-level model that combines a land-use simulation and a crop pattern *** output of the first level is the spatial distribution of the cropland,which is then used as the input for the second level,which allocates crop censuses to individual gridded cells according to certain *** method was tested using data from 2000 to 2019 from Heilongjiang Province,China,and was validated using remote sensing *** results show that this method has high accuracy for crop area *** crop pattern datasets over a given time period can be important supplementary information for remote sensing and thus support a wide range of application in agricultural land systems.

关键词： crop planting pattern spatialization simulation spatiotemporal change remote sensing

The Orthogonal Bases of Exponential Functions Based on Moran-Sierpinski Measures

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Acta Mathematica Sinica,English Series 2024年第7期40卷 1804-1824页

作者： Qi Rong DENG Xing Gang HE ming Tian li Yuan ling ye School of Mathematics and Statistics Center for Applied Mathematics of Fujian Province&Key Laboratory of Analytical Mathematics and Applications(Ministry of Education)Fujian Normal UniversityFuzhou350117P.R.China School of Mathematics and Statistics Key Lab NAA-MOE and Hubei Key Lab-Math.Sci.Central China Normal UniversityWuhan430079P.R.China School of Mathematical Sciences&South China Research Center for Applied Mathematics and Interdisciplinary Studies South China Normal UniversityGuangzhou510631P.R.China

Let An∈M2(ℤ)be integral matrices such that the infinite convolution of Dirac measures with equal weightsμ{A_(n),n≥1}δA_(1)^(-1)D*δA_(1)^(-1)A_(2)^(-2)D*…is a probability measure with compact support,where D={(0,0)^(t),(1,0)^(t),(0,1)^(t)}is the Sierpinski *** prove that there exists a setΛ⊂ℝ2 such that the family{e2πi〈λ,x〉:λ∈Λ} is an orthonormal basis of L^(2)(μ{A_(n),n≥1})if and only if 1/3(1,-1)A_(n)∈Z^(2)for n≥2 under some metric conditions on A_(n).

关键词： Moran-Sierpinski measures orthonormal basis of exponential functions self-affine measures spectral measures