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Ground validation of Fengyun-4A and Global Precipitation Measurement satellite observations over an alpine and canyon basin of the southeastern Tibetan Plateau

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Journal of Mountain Science 2022年第12期19卷 3568-3581页

作者： LONG Yin-ping CHEN Gong-yan ma Qin-min CHEN Jun College of Environmental and Resource Science Chengdu University of Information TechnologyChengdu 610225China Linzhi Meteorological Bureau Linzhi 860000China

Satellite-based precipitation observations with high spatiotemporal resolution are essential for studying rainfall-induced natural hazards,especially in alpine and canyon areas of the southeastern Tibetan Plateau,which are prone to such hazards yet sparsely ***,we evaluated precipitation estimated from the Chinese Fengyun-4A meteorological satellite(FY-4A AGRI)versus the Integrated Multi-satellitE Retrievals for GPM(IMERG),by using rain gauge data collected in the Parlung Zangbo Basin from may through September in both 2018 and *** results showed that(1)FY-4A AGRI generated smaller values of RMSE(root mean square error)on hourly to daily scales,and larger correlation coefficients(R-values)and smaller RMSE values for both moderate and heavy rain,indicating its greater accuracy at rainfall estimation,which is most likely due to the denser rain gauge network at a finer temporal scale used when calibrating FY-4A AGRI;(2)Both satellite products underestimated the volume of moderate and heavy rain,with the larger degree of underestimation by FY-4A AGRI,which could lower their performance in flood monitoring and forecasting;(3)Worse performance and greater inconsistency between the two products were observed in high-elevation areas,perhaps because of orographic cloud effects in these mountainous areas;and(4)Both products revealed that the Gangrigabu Range blocked incoming water vapor from the southwest monsoon,with a better representation of the spatial pattern and spatial variability produced by *** improve precipitation estimation,the effects of complex terrain should be explicitly incorporated into the retrieval algorithms,with more gauged observations in a denser network and at a finer temporal scale needed to robustly calibrate the satellite-based estimates.

关键词： Satellite precipitation Evaluation Fengyun satellite IMERG Mountainous area Parlung Zangbo Basin

The combination of EGCG with warfarin reduces deep vein thrombosis in rabbits through modulating HIF-1αand VEGF via the PI3K/AKT and ERK1/2 signaling pathways

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Chinese Journal of Natural Medicines 2022年第9期20卷 679-690页

作者： LI yan GE Jing-ping ma Ke YIN Yuan-Yuan HE Juan GU Jian-ping Department of Vascular and Interventional Radiology Nanjing First HospitalNanjing Medical UniversityNanjing 210006China Department of Acupuncture Qinhuai District Hospital of Traditional Chinese MedicineNanjing 210000China

Deep venous thrombosis(DVT)poses a major challenge to public health *** cell injury evokes inflammatory and oxidative responses that contribute to thrombus *** polyphenol(TP)in the form of epigallocatechin-3-gallate(EGCG)has anti-inflammatory and oxidative effect that may ameliorate ***,the precise mechanism remains incompletely *** current study was designed to investigate the anti-DVT mechanism of EGCG in combination with warfarin(an oral anticoagulant).Rabbits were randomly divided into five groups.A DVT model of rats was established through ligation of the inferior vena cava(IVC)and left common iliac vein,and the animals were orally administered with EGCG,warfarin,or vehicle for seven *** vitro studies included pretreatment of human umbilical vein endothelial cells(HUVECs)with different concentrations of EGCG for 2 h before exposure to hydrogen *** weight and length were *** changes were observed by hematoxylin-eosin *** samples were collected for detecting coagulation function,including thrombin and prothrombin times,activated partial thromboplastin time,and fibrinogen *** expression in thrombosed IVCs and HUVECs was evaluated by Western blot,immunohistochemical analysis,and/or immunofluorescence ***-qPCR was used to determine the levels of AGTR-1 and VEGF mRNA in IVCs and *** viability of HUVECs was examined by CCK-8 *** cytometry was performed to detect cell apoptosis and ROS generation was assessed by 2′,7ʹ-dichlorofluorescein diacetate *** vitro and in vivo studies showed that EGCG combined with warfarin significantly reduced thrombus weight and length,and apoptosis in *** findings indicated that the combination of EGCG and warfarin protects HUVECs from oxidative stress and prevents ***,HIF-1αsilencing weakened these effects,which indicated that HIF-1αmay participate in ***,HIF-1αsilencin

关键词： Deep vein thrombosis EGCG Warfarin HIF-1α VEGF PI3K/AKT ERK1/2

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自动跟光太阳能光伏发电系统设计

电子设计工程 2017年第12期25卷 93-96,100页

作者：刁颖陶国彬王中钰杜艳萍马磊东北石油大学电气信息工程学院黑龙江大庆163318 大庆装备制造集团射孔弹厂黑龙江大庆163853 大庆油田矿区服务事业部物业管理二公司黑龙江大庆163411 东北石油大学地球科学学院黑龙江大庆163318

本文针对光伏系统发电效率偏低问题进行改进设计研究,设计采用光伏系统自动跟光技术,针对光电检测模块、计算机控制模块、步进电机驱动模块进行研究,再对跟光系统跟光原理进行分析,在此基础上完成自动跟光太阳能光伏发电系统的整体设计... 详细信息

本文针对光伏系统发电效率偏低问题进行改进设计研究,设计采用光伏系统自动跟光技术,针对光电检测模块、计算机控制模块、步进电机驱动模块进行研究,再对跟光系统跟光原理进行分析,在此基础上完成自动跟光太阳能光伏发电系统的整体设计。通过对自动跟光式光伏发电系统与固定式光伏发电系统的测试,数据结果表明,该系统发电效率相比于固定式发电效率提升37%,系统能够准确跟踪太阳位置,系统运行稳定。

关键词：太阳能光伏发电发电效率自动跟光

OvBNN authentication based on cooperative signature for wireless sensor networks

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High Technology Letters 2018年第3期24卷 287-295页

作者：秦丹阳 Zhang yan ma Jingya Ji ping Key Lab of Electronic and Communication Engineering Heilongjiang University

The universality of the application of wireless sensor networks( WSN) makes more attention be paid on the security problem. Node authentication is not only the basis of network security,but also the premise of key management and secure routing protocol. Although the signature mechanism based on symmetric encryption is high in energy efficiency,it is vulnerable to be attacked and there is a time delay during authentication. Traditional public key encryption mechanism with improvement in security brings in complex algorithm and costs much time,which is not suitable for WSN. In this paper,a signature authentication mechanism,an optimized variant Bellare Namprempre Neven( OvBNN) is presented to quickly complete the authentication by mutual cooperation between nodes so as to make the nodes use the intermediate calculation results of their neighbor nodes *** results show that the proposed mechanism is superior to traditional authentication mechanisms both in energy consumption and authentication time.

关键词： optimized variant Bellare Namprempre Neven (OvBNN) digital signature authentication speed energy consumption wireless sensor networks (WSN)

Preparation of WO_(3) nanorods with high specific surface area using double-walled carbon nanotubes as template

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Rare Metals 2022年第3期41卷 1051-1056页

作者： yan-Hong Yin Chun-An ma Zi-ping Wu Li-Tao Chen You-Qun Chu State Key Laboratory Breeding Base for Green Chemistry Synthesis Technology International Science and Technology Cooperation Base of Energy Materials and ApplicationCollege of Chemical Engineering and Materials ScienceZhejiang University of TechnologyHangzhou 310032China Engineering Research Center of High-Efﬁciency Development and Application Technology of Tungsten Resources(Ministry of Education) School of Materials Science and EngineeringJiangxi University of Science and TechnologyGanzhou 341000China

The preparation of WO_(3) nanorods by double-walled carbon nanotube(DWCNT)template was investi-gated in this *** to that the prepared H_(2)WO_(4)can be isolated by the homogenously dispersed DWCNT bun-dles and secondary accumulation can be avoided effec-tively,the growth of H_(2)WO_(4) can be restrained,and H_(2)WO_(4) nanorods with diameter of 10–50 nm can be *** calcination of the prepared DWCNT/H_(2)WO_(4) com-posite in oxygen,WO_(3) nanorods with diameter of 10–100 nm and high specific surface area of 16.4 m^(2)·g^(-1) can be *** is concluded that the DWCNTs play an im-portant role in the effective mediation of the morphology and size of nano-WO_(3).

关键词： Tungsten oxide Nanorods Double-walled carbon nanotubes Template

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獭兔大肠杆菌性出血肺炎的诊治

畜牧兽医杂志 2000年第4期19卷 7-8页

作者：赫晓燕刘晋平马海利武继民山西农业大学动物科技学院太谷030801 山西长治畜牧局

对临床上突然死亡、肺严重出血的獭兔进行了病原分离、生化试验、血清型鉴定、致病性试验 ,证明所分离病原为致病性大肠杆菌 O55和 O80 ,并选用敏感药物进行预防。

关键词：獭兔大肠杆菌出血性肺炎诊治

Silencing transformer and transformer-2 in Zeugodacus cucurbitae causes defective sex determination with inviability of most pseudomales

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Journal of Integrative Agriculture 2024年第3期23卷 938-947页

作者： Qin ma Zizhen Fan ping Wang Siya ma Jian Wen Fengqin Cao Xianwu Lin Rihui yan Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests of Ministry of Education School of Plant ProtectionHainan UniversityHaikou 570228China School of Life Sciences HainanUniversityHaikou 570228China Hainan Yazhou Bay Seed Lab Sanya 572000China

transformer is a switch gene for sex determination in many insects, which cooperates with transformer-2 that is expressed in both sexes to regulate female differentiation, particularly in dipterans. Zeugodacus cucurbitae(Coquillett) is a very destructive pest worldwide, however, its sex determination pathway remains largely uncharacterized. Here, we show that the female sex ratio is sharply reduced with knockdown of either transformer or transformer-2 by RNA interference in early embryos of Z. cucurbitae. Most of the males grown from the embryos with transient transformer and transformer-2 suppression mated with wild-type females and produced mixed sex progeny, with one exception that produced only female progeny, and all of the few remaining males failed to mate with wild-type females and produced no progeny. The exceptional male and those males with mating failure were XX pseudomales as determined by the detection of Y chromosome-linked maleness-on-the-Y, indicating that most XX pseudomales are not viable. The phenotypes of transformer and transformer-2 suggest that they play a key role in regulating sex determination and are required for female sexual development of Z. cucurbitae. Our results will be beneficial to the understanding of sex determination in Z. cucurbitae and can facilitate the development of genetic sexing strains for its biological control.

关键词： Zeugodacus cucurbitae transformer transformer-2 sex determination RNA interference biological control

Modeling study on the flow patterns of gas–liquid flow for fast decarburization during the RH process

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International Journal of Minerals,Metallurgy and materials 2018年第2期25卷 153-163页

作者： Yi-hong Li yan-ping Bao Rui Wang Li-feng ma Jian-sheng Liu Collaborative Innovation Centre of Taiyuan Heavy machinery Equipment and School of materials Science and Engineering Taiyuan University of Science and Technology State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing School of materials Science and Engineering North University of China

A water model and a high-speed video camera were utilized in the 300-t RH equipment to study the effect of steel flow patterns in a vacuum chamber on fast decarburization and a superior flow-pattern map was obtained during the practical RH process. There are three flow patterns with different bubbling characteristics and steel surface states in the vacuum chamber： boiling pattern（BP）, transition pattern（TP）, and wave pattern（WP）. The effect of the liquid-steel level and the residence time of the steel in the chamber on flow patterns and decarburization reaction were investigated, respectively. The liquid-steel level significantly affected the flow-pattern transition from BP to WP, and the residence time and reaction area were crucial to evaluate the whole decarburization process rather than the circulation flow rate and mixing time. A superior flow-pattern map during the practical RH process showed that the steel flow pattern changed from BP to TP quickly, and then remained as TP until the end of decarburization.

关键词： modeling study flow pattern vacuum chamber residence time decarburization RH process

Effects of different Helicobacter pylori culture filtrates on growth of gastric epithelial cells

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World Journal of Gastroenterology 2008年第23期14卷 3745-3749页

作者： yan-Guo yan Gang Zhao Jin-ping ma Shi-Rong Cai Wen-Hua Zhan Department of General Surgery The Affiliated Hospital of Wuhan University of Science & Technology Wuhan 430064 Hubei Province China The Second Department of General Surgery Guangdong Province Hospital Guangzhou 510080 Guangdong Province China Department of Gastrointestinal and Pancreatic Surgery The First Affiliated Hospital Research Center for Gastric Cancer Sun Yat-sen University Guangzhou 510080 Guangdong Province China

AIM:To study the effects of different Helicobacter pylori(H pylori) culture filtrates on growth of gastric epithelial cells. METHODS:Broth culture filtrates of H pylori were prepared. Gastric epithelial cells were treated with the filtrates,and cell growth was determined by growth curve and flow cytometry. DNA damage of gastric epithelial cells was measured by single-cell microgel electrophoresis. RESULTS:Gastric epithelial cells proliferated actively when treated by CagA-gene-positive broth culture filtrates,and colony formation reached 40%. The number of cells in S phase increased compared to controls. Comet assay showed 41.2% comet cells in GES-1 cells treated with CagA-positive filtrates(P man gastric epithelial tumor cells. DNA damage maybe one of the mechanisms involved in the growth changes.

关键词： CagA gene Gastric epithelial cell Heliobacter pylori Single cell microgel electrophoresis