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Seasonality of insect succession on exposed rabbit carrion in Guangzhou, China

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Insect Science 2009年第5期16卷 425-439页

作者： Yan-Wei Shi Xiao-Shan Liu Hai-yang Wang Run-jie zhang State Key Lab for Bio-control and Institute of Entomology Sun Yat-Sen University Guangzhou China

Succession patterns for insect fauna, spanning four seasons, on rabbit carcasses were studied in Guangzhou China from 2006 to 2008. A total of 49 taxa belonging to three orders and 15 families were collected and identified. Four decomposition stages were recognized： fresh, bloated, decay and dry stage. Taxa diversity was higher in bloated and decay stages than fresh and dry stages. Internal and ambient temperatures were measured. Maximum internal temperature arrived earlier in warmer seasons. The sequence of insect succession in this study follows the same general patterns： the Diptera peaked initially, and the Coleoptera peaked later. Chrysomya megacephala was the dominant species in four seasons. Its time point of different development stages on carrion could be the most important indicators for PMI （postmortem interval） estimation in Guangzhou. Yearly and seasonal differences in activities of insects were compared. Alpha diversity indices were calculated. There were no significant differences in Shannon-Wiener index, evenness （J） and dominance （C） between seasons and years. From the Jaccard similarity index, the highest similarity was between winter and spring, while the lowest was between summer and winter. Some species occurring exclusively in one season may be important to characterize different seasons. A list of the insect taxa associated with above-ground rabbit carrion during the four seasons was compiled, which can be used for estimating time since death in similar bio-climate areas.

关键词： China forensic entomology Guangzhou insect succession postmortem interval

Effect of chip rate on the ranging accuracy in a regenerative pseudo-noise ranging system

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第2期12卷 132-139页

作者： Jian-wen JIANG Wei-jun yang Chao-jie zhang Xiao-jun JIN Zhong-he JIN Department of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

The ranging accuracy of a pseudo-noise ranging system is mainly decided by range jitter and time delay discrimination. Many factors can affect the ranging accuracy, one of which is the chip rate. In digital signal processing, the time delay discrimination and autocorrelation function of sampled ranging sequences of different chip rates are very different. An approximation simulation model is established according to an in-phase quadrature (I/Q) correlator which is used to evaluate the time delay. Simulation results of the range jitter and time delay discrimination show that the chip rate which provides a non-integer sample-to-chip rate ratio can achieve a higher ranging accuracy, and some test results validate the simulation model. In some design missions, the simulation results may help to select an optimum sample-to-chip rate ratio to satisfy the design requirement on the ranging accuracy.

关键词： Ranging accuracy Range jitter Time delay discrimination Sample-to-chip rate ratio Integration time Autocorrelation function Fractional chip period delay

Influence of Package Form on ElectromagneticPulse Protective Characteristics of Transient Voltage Suppressor Transistors

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高电压技术 2014年第6期40卷 1683-1687页

作者： yang jie zhang xijun DONG Kangning ResearchInstituteofElectrostaticandElectromagneticProtection MechanicalEngineeringCollegeShijiazhuang050003China

Adding transient voltage suppressor (TVS) transistors to an electric circuit is an important method to protect it from the fast-risetime electromagnetic pulse (FREMP) damage. The package form of the TVS transistors influences the volume, response time, and power consumption of the circuit. However, the influence of the package form on the clamp voltage of TVS transistors affected by FREMP is not considered yet. In this article, the results of the experiment comparing the influence of package form are described, where the rectangular pulses with rise time shorter than 1 ns are used to test protection performance of three different TVS transistors, which have the same framework but different breakdown voltages. The influence of the different package forms on the clamp voltage is analyzed by using the fitting model. It is found that the package form of TVS transistors has less influence on the current characteristics of their protection performance, but more on the voltage characteristics. It is concluded that the diameter or width of the TVS transistors is the main factor determining the clamp voltage. Thus, the diameter or width of the TVS transistors should be big enough to ensure the stabilization of clamp voltage, but, at the same time, fit the allowing volume.

关键词：瞬态电压抑制器晶体管防护性能包装形式瞬变电压抑制器上升时间保护性能封装形式

Experimental Study on Convective Heat Transfer in Tube-Side of Water Jacket-Tube Heat Exchanger by Electrohydrodynamics Effect

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Wuhan University Journal of Natural Sciences 2011年第1期16卷 49-54页

作者： yang Xia zhang jie WU Yanyang zhang Tao MAO Zhihui School of Mechanical and Electrical Engineering WuhanInstitute of Technology Wuhan 430073 Hubei China

The electrohydrodynamics （EHD） enhancement of convection heat transfer of water in a jacket tube heat exchanger was studied through an experimental method in this paper. In the experiment,a DC high voltage electrode was set in the central tube-side of the heat exchanger,and the high voltage electrode in the tube-side was adjustable in the range of 0-40 kV. Five differ-ent combinations of heat transfer enhancement experiments were conducted under the different voltage and rate of flow. The results indicate that the maximal enhancement coefficient θ is 1.224 when the flow rate of tube-side inlet is 0.1 m3/h. It is proved that,for the work medium of water,the convective heat transfer can be enhanced by applying high electric field. The performance of EHD-enhanced is sensitive to the variation of flow rate,and in the same flow rate,there exist an optimized voltage in the EHD-enhanced process ra-ther than the monotonic positive-correlation relationship.

关键词： electrohydrodynamics (EHD) heat transfer enhance-ment water jacket-tube heat exchanger convection heat transfer

Matrix Solid-phase Dispersion Extraction of Alkaloids from the Roots of Aconitum kusnezoffii Reichb

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Chemical Research in Chinese Universities 2011年第1期27卷 23-27页

作者： WEI Wei LI Xu-wen SHI Xiao-lei ZHOU Hong-yu yang Rui-jie zhang Han-qi JIN Yong-ri College of Chemistry Jilin University Changchun 130012 P. R. China

Matrix solid-phase dispersion（MSPD） was developed for the extraction of four alkaloids, including aconitine, mesaconitine, hypaconitine and deoxyaconitine, from the roots ofAconitum kusnezoffii Reichb. The determination of the analyte was carried out by high performance liquid chromatography with UV detection. The alkaline alumina was used as sorbent. The mixture of acetonitrile and water was used as elution solvent. Several extraction parameters, such as type of sorbent, the ratio of sample to solid support material, type of the elution solvent and the volume of the elution solvent were tested. Mean recoveries ranged from 93.16% to 102.73%, with relative standard deviations from 0.27% to 4.17%. With the extraction efficiency and time expenditure taken into account, MSPD extraction should be a comparatively good method.

关键词： Matrix solid-phase dispersion Aconitine-type alkaloid Aconitum kusnezoffii Reichb. Extraction High-performance liquid chromatography 1005-9040(2011 )-01-023-05

Effects of the extrusion parameters on microstructure,texture and room temperature mechanical properties of extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 136-146页

作者： Chenjin zhang Guangyu yang Lei Xiao Zhiyong Kan Jing Guo Qiang Li Wanqi jie State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China College of Materials Science and Engineering Fuzhou UniversityFuzhou 350108China College of Chemistry and Environmental Science Qujing Normal UniversityQujing 655011China

Microstructure,texture,and mechanical properties of the extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy were investigated at different extrusion temperatures(260 and 320℃),extrusion ratios(10:1,15:1,and 30:1),and extrusion speeds(3 and 6 mm/s).The experimental results exhibited that the grain sizes after extrusion were much finer than that of the homogenized alloy,and the second phase showed streamline distribution along the extrusion direction(ED).With extrusion temperature increased from 260 to 320℃,the microstructure,texture,and mechanical properties of alloys changed *** dynamic recrystallization(DRX)degree and grain sizes enhanced as the extrusion ratio increased from 10:1 to 30:1,and the strength gradually decreased but elongation(EL)*** the extrusion speed increased from 3 to 6 mm/s,the grain sizes and DRX degree increased significantly,and the samples presented the typical-rare-earth(RE)*** alloy extruded at 260℃ with extrusion ratio of 10:1 and extrusion speed of 3 mm/s showed the tensile yield strength(TYS)of 213 MPa and EL of 30.6%.After quantitatively analyzing the contribution of strengthening mechanisms,it was found that the grain boundary strengthening and dislocation strengthening played major roles among strengthening *** results provide some guidelines for enlarging the industrial application of extruded Mg-RE alloy.

关键词： Mg-rare earth alloys extrusion temperature extrusion ratio extrusion speed strengthening mechanisms

Gamma-glutamyl transferase 5 overexpression in cerebrovascular endothelial cells improves brain pathology,cognition,and behavior in APP/PS1 mice

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Neural Regeneration Research 2025年第2期20卷 533-547页

作者： Yanli zhang Tian Li jie Miao Zhina zhang Mingxuan yang Zhuoran Wang Bo yang Jiawei zhang Haiting Li Qiang Su Junhong Guo Department of Neurology First Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Neurology Sixth Hospital of Shanxi Medical University(General Hospital of Tisco)TaiyuanShanxi ProvinceChina Department of Physiology Key Laboratory of Cellular PhysiologyMinistry of EducationShanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Hernia and Abdominal Wall Surgery Shanxi Bethune HospitalShanxi Academy of Medical SciencesTongji Shanxi HospitalThird Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Laboratory Medicine of Fenyang College Shanxi Medical UniversityFenyangShanxi ProvinceChina

In patients with Alzheimer’s disease,gamma-glutamyl transferase 5(GGT5)expression has been observed to be downregulated in cerebrovascular endothelial ***,the functional role of GGT5 in the development of Alzheimer’s disease remains *** study aimed to explore the effect of GGT5 on cognitive function and brain pathology in an APP/PS1 mouse model of Alzheimer’s disease,as well as the underlying *** observed a significant reduction in GGT5 expression in two in vitro models of Alzheimer’s disease(Aβ_(1-42)-treated hCMEC/D3 and bEnd.3 cells),as well as in the APP/PS1 mouse ***,injection of APP/PS1 mice with an adeno-associated virus encoding GGT5 enhanced hippocampal synaptic plasticity and mitigated cognitive ***,increasing GGT5 expression in cerebrovascular endothelial cells reduced levels of both soluble and insoluble amyloid-βin the brains of APP/PS1 *** effect may be attributable to inhibition of the expression ofβ-site APP cleaving enzyme 1,which is mediated by nuclear factor-kappa *** findings demonstrate that GGT5 expression in cerebrovascular endothelial cells is inversely associated with Alzheimer’s disease pathogenesis,and that GGT5 upregulation mitigates cognitive deficits in APP/PS1 *** findings suggest that GGT5 expression in cerebrovascular endothelial cells is a potential therapeutic target and biomarker for Alzheimer’s disease.

关键词： Alzheimer’s disease amyloid-β APP/PS1 mice cerebrovascular endothelial cells cognitive deficits gamma-glutamyl transferase 5 neurovascular unit nuclear factor‐kappa B synaptic plasticity β-site APP cleaving enzyme 1

A follow-up study of women with a history of severe preeclampsia： relationship between metabolic syndrome and preeclampsia

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Chinese Medical Journal 2011年第5期124卷 775-779页

作者： LU jie ZHAO yang-yu QIAO jie zhang Hong-jun GE Lin WEI Yuan Department of Gynecology & Obstetrics Peking University Third Hospital Beijing 100191 China

Background Women with a history of preeclampsia have twice the risk of cardiovascular diseases, and there is a graded relationship between the severity of preeclampsia and the risk of cardiac disease. Moreover, metabolic scores are associated with developing preeclampsia. However, since there are no diagnostic criteria for metabolic syndrome during pregnancy and pregnant women undergo metabolic changes, it is difficult to elucidate the relationship between preeclampsia and metabolic syndrome. We carried out a cross-sectional study to investigate the relationship between metabolic syndrome and preeclampsia among women with a history of severe preeclampsia shortly after an indexed *** We recruited 62 women with a history of severe preeclampsia 1 to 3 years after an indexed pregnancy. Blood pressure and body compositional indices were recorded. Fasting blood samples were tested for glucose, total cholesterol high density lipoprotein-cholesterol, low density lipoprotein-cholesterol, triglycerides, and insulin. A questionnaire was used to collect demographic data including pre-pregnancy weight and family history of diseases associated with cardiovascular diseases. Criteria for metabolic syndrome were defined by the National Cholesterol Education Program, Adult Treatment Panel III 2001 （NCEP III） and International Diabetes Federation 2005 （IDF）. Data were analyzed by the （α2 test and multivariate Logistic *** According to NCEP III and IDF standards, 17 （27%） and 24 （39%） women, respectively, were identified as having metabolic syndrome. Being overweight pre-pregnancy and currently overweight were risk factors, and currently overweight was an independent risk factor. A combination of blood pressure and waist circumference was predictive of metabolic syndrome with a sensitivity of 91.67% and specificity of 94.74%. Conclusions An unfavorable metabolic constitution in women may lead to metabolic syndrome, preeclampsia, and long-term cardiovascular

关键词： metabolic syndrome severe preeclampsia cardiovascular disease

基于多示例学习径向基函数神经网络的刻蚀设备异常侦测

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上海交通大学学报 2016年第12期50卷 1816-1822页

作者：杨俊刚张洁上海交通大学机械与动力工程学院上海200240

针对晶圆制造系统刻蚀设备工作过程中的"时间-晶圆-设备参数"三维结构数据导致常规分析方法难以应用的难题,提出了一种基于多示例学习径向基函数(RBF)神经网络的异常侦测方法.该方法应对常规点间距离无法解决示例间不匹配程度衡量问题... 详细信息

针对晶圆制造系统刻蚀设备工作过程中的"时间-晶圆-设备参数"三维结构数据导致常规分析方法难以应用的难题,提出了一种基于多示例学习径向基函数(RBF)神经网络的异常侦测方法.该方法应对常规点间距离无法解决示例间不匹配程度衡量问题的不足,改进了距离计算方式,可用既含正常数据又含异常数据的数据包来训练和侦测.运用实验设计理论优化了神经网络参数,使用交叉验证方法将采集到的刻蚀设备运行数据按晶圆加工批次划分为不同示例,作为RBF网络的训练和测试数据,来侦测刻蚀设备异常,提高侦测的稳定性.实验结果表明,该方法可识别多批次多变量情况下的设备异常,适合于刻蚀设备运行过程中多种产品并存情况下的异常侦测.

关键词：异常侦测多示例学习径向基函数神经网络刻蚀晶圆制造系统