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CDMA分层蜂窝移动通信系统的性能分析

高技术通讯 2008年第3期18卷 238-242页

作者：蒋占军潘文王炎尤肖虎东南大学移动通信国家重点实验室南京210096 兰州交通大学电子与信息工程学院兰州730070

分析了 CDMA 分层蜂窝移动通信系统(HCMS)网络覆盖特性,在此基础上提出了一种由宏小区和分布式天线系统(DAS)组成的双层 HCMS,即宏小区/DAS 结构,并将其与CDMA 宏小区/微小区双层蜂窝系统作了比较。网络覆盖特性分析表明,该网络结构更... 详细信息

分析了 CDMA 分层蜂窝移动通信系统(HCMS)网络覆盖特性,在此基础上提出了一种由宏小区和分布式天线系统(DAS)组成的双层 HCMS,即宏小区/DAS 结构,并将其与CDMA 宏小区/微小区双层蜂窝系统作了比较。网络覆盖特性分析表明,该网络结构更有利于降低网络建设和功率控制的复杂性;信干比仿真结果表明,该网络结构改善了系统的上下行链路的信干比,从而有利于提高 CDMA 蜂窝移动通信系统的系统容量。

关键词： CDMA 分层网络结构分布式天线系统远端接入单元选择

CHANGES OF pan EVAPORATION IN THE UPPER REACH OF THE yanGTZE RIVER

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Journal of Hydrodynamics 2011年第4期23卷 503-509页

作者： RONG yan-shu wang wen jiang Hai-yan College of Hydrology and Water Resources Hohai University Nanjing 210098 China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China

The upper reach of the yangtze River, 4 511 km long from west to east, contains a great amount of water resources of the yangtze River Basin. This article studies the characteristics of the pan evaporation, the related meteorological variables, and their effects on the pan evaporation, based on the data of the daily pan evaporation （1980-2008） and other meteorological variables （1961-2008）. The results show that the linear trend of the pan evaporation has remarkable regional features, i.e., the decrease trend in the southwest and the increase trend in the northeast of the investigated region, and the yangtze River is approximately the boundary of these trends. The meteorological variables have different effects on the pan evaporation depending on the fact that they are in the category the thermal variables or the dynamic variables. The thermal meteorological variables （i.e., air temperature, diurnal temperature range, and sunshine duration） have positive partial correlations with the pan evaporation, while the dynamic ones （air pressure, rainfall, and relateive humidity） have negative correlations with the pan evaporation. The correlation of the wind speed remains to be investigated.

关键词： linear time trend meteorological variable pan evaporation partial correlation yangtze River

Spatial distribution characteristics and main controlling factors of germanium in soil of northern Dabie Mountains, China

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Journal of Groundwater Science and Engineering 2022年第4期10卷 381-392页

作者： Qiu-yao Dong Jiao Xiang Chao Song pan wang Hao-tian wen Ming-jiang yan Institute of Hydrogeological and Environmental Geology Chinese Academy of GeosciencesShijiazhuang 050061China Key laboratory of Quaternary Chronology and Hydro-Environmental Evolution China Geological SurveyZhengding 050083HebeiChina 107 Geological Team Chongqing Bureau of Geology and Minerals ExplorationChongqing 401120China School of Earth Science and Resources China University of GeosciencesBeijing 100083China

With the increasing application of germanium(Ge)elements in modern industry,military and medical health industries,especially with the growing demand for Ge-rich agricultural products,the study of Ge-rich soil has become particularly important,but the enrichment pattern and control factors of Ge-rich soil are still not well understood due to the high dispersion and high migration of Ge-rich *** this paper,495 surface soil(0-20 cm)and 149 deep soil(150-200 cm)samples were collected from the northern foothills of Dabie Mountain using a double-layer grid layout,and the spatial distribution and enrichment characteristics of Ge were studied by high-resolution method,and the controlling factors affecting the distribution of Ge-rich soil was analyzed by geo-statistics and spatial *** results show an average Ge content of 1.34 mg/kg for the surface and 1.36 mg/kg for the deep *** the assessment grade classification of surface and deep soil for Ge,the abundant and sub-abundant grades account for 37.97%and 31.70%,respectively,covering 752 km2 and 634 *** Ge-rich regions are distributed in concentrated strips in the north-central part of the studied region,and there is no clear pattern in the spatial distribution of deep *** the areas under study,such as Fenlukou,Dingji,and jiangjiadian,the surface soil is very rich in Ge and has a high enrichment factor,which is valuable for agricultural *** surface soils,river deposits and shallow metamorphic rock parent materials have the highest content of Ge,while in deep soils,the highest content has been found in the parent material of moderately acidic *** surface and deep soils have the highest Ge content in purple paddy soils and plain *** source of Ge in the soils of the study area is most influenced by the lithology of the soil-forming parent material,while the distribution of Ge in the surface soils is jointly influenced by pH,SiO_(2),TFe_(2)O_(3),and Al_(2)O_(3) in the ***

关键词： Germanium Soil Enrichment feature Distribution characteristics Influencing factors

Charge regulation by ferromagnetic metal/LiF spin-polarized interface for high-performance Li metal anodes

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Rare Metals 2024年第3期43卷 995-1005页

作者： Ming-yang Feng Shuang Zhou Yi-Fang Zhang Ya-Ping wang Chun-yan Fu Jian-wen Li Yuan-Lang Wan Zhi-Jia Zhang Yong jiang An-Qiang pan State Key Laboratory of Powder Metallurgy School of Materials Science and EngineeringCentral South UniversityChangsha410083China State Key Laboratory of Separation Membranes and Membrane Processes Tianjin Key Laboratory of Advanced Fibers and Energy StorageSchool of Material Science and EngineeringTiangong UniversityTianjin300387China School of Materials Science and Engineering Hebei University of TechnologyTianjin300130China

The interfacial characteristics of the Li metal anode(LMA)play a crucial role in its overall *** various materials being applied to modify the interface,a comprehensive understanding of their specific mechanisms remains to be ***,we have prepared carbon cloth(CC)frameworks with their surfaces modified using ferromagnetic metal/LiF heterogeneous films(T^(M)-LiF-CC)as the substrate for LMA,which exhibit superior electrochemical *** ferromagnetic Co as a representative example,our study demonstrates that the enhanced performance of Co-LiF-CC,compared to bare CC,is attributed to the spinpolarized interface contributed by the Co/LiF *** and LiF play individual roles in redistributing electrons and Li^(+)to promote homogeneous Li *** nanoparticles play a crucial role in generating strong surface capacitance by storing electrons in spin-split bands,while LiF,with low surface diffusion barriers,ensures fast transportation of Li^(+).The Co-LiF-CC@Li electrodes deliver long lives of 7400 and 3600 h at 1 and 2 mA·cm^(-2)in symmetric cells,respectively;moreover,they enable full batteries with high and durable capacities,particularly when the N/P ratios are low(3.3 or even 1.7).

关键词： Lithium metal anode Interfacial charge Ferromagnetic metal Lithium fluoride Spin polarization

Effects of Differential First-Line Antiretroviral Therapy(ART)Regimens on Mortality among HIV/AIDS Children in Southwest China:A 15-year Retrospective Cohort Study

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Biomedical and Environmental Sciences 2023年第11期36卷 1079-1083页

作者： CHEN Qiu Li LIAO yan yan QIN Shan Fang LU Chun yan pan Pei jiang wang Hai Long jiang Jun Jun ZHENG Zhi Gang QIN Feng Xiang HONG wen NING Chuan Yi YE Li LIANG Hao Guangxi Key Laboratory of AIDS Prevention and Treatment School of Public HealthGuangxi Medical UniversityNanning 530021GuangxiChina Biosafety IlI Laboratory Life Science InstituteGuangxi Medical UniversityNanning 530021GuangxiChina Guangxi AIDS Diagnosis and Treatment Quality Control Center Chest Hospital of Guangxi Zhuang Autonomous RegionLiuzhou 545005GuangxiChina Guangxi Center for Disease Prevention and Control Nanning 530021GuangxiChina Nursing College Guangxi Medical UniversityNanning 530021GuangxiChina

Human immunodeficiency virus(HIV)is a serious public health ***,1.7 million(1.3–2.1 million)children aged 0–14 were living with HIV at the end of 2021,90%of whom lived in low-and middle-income *** Immune Deficiency ... 详细信息

关键词： mortality Therapy HIV/AIDS

His bundle pacing versus left bundle branch pacing on ventricular function in atrial fibrillation patients referred for pacing:a prospective crossover comparison

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Journal of Geriatric Cardiology 2023年第1期20卷 51-60页

作者： yang YE Bo GAO Yuan LV Tian-Tian XU Si-Si ZHANG Xiao-Li LU Ying yanG Dong-Mei jiang Yi-wen pan Xia SHENG Bei wang yan-Kai MAO Zu-wen ZHANG Shi-Quan CHEN Jie-Fang ZHANG Li wang jiang-Fen jiang Ya-Xun SUN yan MA Fei-Ling wang Min wang Hong HE Chen-yang jiang Guo-Sheng FU Department of Cardiology Sir Run Run Shaw HospitalCollege of MedicineZhejiang UniversityHangzhouZhejiang ProvinceChina Department of Cardiology Zhejiang Rongjun HospitalJiaxingZhejiang ProvinceChina Department of Cardiology Lishui People’s HospitalLishuiZhejiang ProvinceChina Department of Cardiology Ningbo Ninth HospitalNingboZhejiang ProvinceChina Department of Cardiology Anji people’s HospitalNingboZhejiang ProvinceChina Department of Diagnostic Ultrasound and Echocardiography Sir Run Run Shaw HospitalCollege of MedicineZhejiang UniversityHangzhouZhejiang ProvinceChina

BACKGROUND His bundle pacing(HBP)and left bundle branch pacing(LBBP)both provide physiologic pacing which maintain left ventricular *** both improve heart failure(HF)symptoms in atrial fibrillation(AF)*** aimed to assess the intra-patient comparison of ventricular function and remodeling as well as leads parameters corresponding to two pacing modalities in AF patients referred for pacing in intermediate *** Uncontrolled tachycardia AF patients with both leads implantation successfully were randomized to either *** measurements,New York Heart Association(NYHA)classification,quality-of-life assessments and leads parameters were obtained at baseline and at each 6-month follow *** ventricular function including the left ventricular endosystolic volume(LVESV),left ventricular ejection fraction(LVEF)and right ventricular(RV)function quantified by tricuspid annular plane systolic excursion(TAPSE)were all *** Consecutively twenty-eight patients implanted with both HBP and LBBP leads successfully were enrolled(69.1±8.1 years,53.6% male,LVEF 59.2%±13.7%).The LVESV was improved by both pacing modalities in all patients(n=23)and the LVEF was improved in patients with baseline LVEF at less than 50%(n=6).The TAPSE was improved by HBP but not LBBP(n=23).CONCLUSION In this crossover comparison between HBP and LBBP,LBBP was found to have an equivalent effect on LV function and remodeling but better and more stable parameters in AF patients with uncontrolled ventricular rates referred for atrioventricular node(AVN)*** could be preferred in patients with reduced TAPSE at baseline rather than LBBP.

关键词： ventricular patients bundle

Health risk assessment of heavy metals in soils and crops in a mining area(Au-Ag-Cutrona-oil et al.) of the Nanyang Basin, Henan Province, China

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China Geology 2023年第4期6卷 567-579页

作者： Qiu-yao Dong Hao-tian wen pan wang Chao Song Shu-ya Lai Zhen-jing yang Yuan-yi Zhao Ming-jiang yan Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological SciencesShijiazhuang 050061China Key Laboratory of Quaternary Chronology and Hydro-Environmental Evolution China Geological SurveyMinistry of Natural ResourcesShijiazhuang 050061China School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China School of Earth Sciences Hebei GEO UniversityShijiazhuang 050031China Institute of Mineral Resources Chinese Academy of Geological SciencesBeijing 100037China

Heavy metal distribution in mining areas has always been a hot research topic due to the special environment of these areas. This study aims to explore the impact of heavy metal pollution on soils and crops in the study area, ensure the safety of local crops and the health of local residents, and provide a basis for the subsequent environmental restoration and the prevention and control of environmental pollution. Based on the analysis of the heavy metal concentrations in local soils and crops, the study investigated the spatial distribution, pollution degrees, and potential ecological risks of heavy metals in the farmland of a mining area in the southeastern Nanyang Basin, Henan province, China explored the sources of heavy metals and assessed the health risks caused by crop intake. The results of this study are as follows. The root soils of crops in the study area suffered heavy metal pollution to varying degrees. The degree of heavy metal pollution in maize fields is higher than that in wheat fields, and both types of fields suffer the most severe Cd pollution. Moreover, the root soils of different crops suffer compound *** root soils in the maize fields suffer severe compound pollution at some sampling positions, whose distribution is similar to that of the mining area. Cd poses the highest potential ecological risks among all heavy metals, and the study area mainly suffers low and moderate comprehensive potential ecological risks. The principal component analysis(PCA) shows that the distribution of Zn, Cd, Pb, and As in soils of the study area is mainly affected by anthropogenic factors such as local mining activities;the distribution of Cr and Ni is primarily controlled by the local geological background;the distribution of Hg is mainly affected by local vehicle exhaust emissions, and the distribution of Cu is influenced by both human activities and the geological background. Different cereal crops in the study area are polluted with heavy metals dom

关键词： Heavy metal Zn-Cd-Pb pollution Cr-Ni pollution As pollution Natural ecosystem Health risk assessment Adult-children health risk Ecological risk index(ERI) Ecological geological engineering Mining activity

Cholesterol paradox in the community-living old adults:is higher better?

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Journal of Geriatric Cardiology 2023年第12期20卷 837-844页

作者： Sheng-Shu wang Shan-Shan yanG Chun-jiang pan Jian-Hua wang Hao-Wei LI Shi-Min CHEN Jun-Kai HAO Xue-Hang LI Rong-Rong LI Bo-yan LI Jun-Han yanG Yue-Ting SHI Huai-Hao LI Ying-Hui BAO wen-Chang wang Sheng-yan du Yao HE Chun-Lin LI Miao LIU Institute of Geriatrics Beijing Key Laboratory of Aging and GeriatricsNational Clinical Research Center for Geriatrics Diseasesthe Second Medical CenterChinese PLA General HospitalBeijingChina Department of Disease Prevention and Control the First Medical CenterChinese PLA General HospitalBeijingChina Department of Disease Control and Prevention Chinese PLA Strategic Support Force Characteristic Medical CenterBeijingChina Department of Health Service the Second Medical CenterChinese PLA General HospitalBeijingChina Department of Epidemiology State Key Laboratory of Kidney DiseasesChinese PLA General HospitalBeijingChina Institute of Endocrinology the Second Medical CenterChinese PLA General HospitalBeijingChina Department of anti-NBC Medicine Chinese PLA Medical SchoolChinese PLA General HospitalBeijingChina

OBJECTIVE To evaluate the associations of lipid indicators and mortality in Beijing Elderly Comprehensive Health Cohort *** A prospective cohort was conducted based on Beijing Elderly Comprehensive Health Cohort Study with 4499 com-munity older *** the baseline survey,the last follow-up was March 31,2021 with an average 8.13 years of *** proportional hazard model was used to estimate the hazard ratios(HR)with 95%CI for cardiovascular disease(CVD)death and all-cause death in associations with baseline lipid *** A total of 4499 participants were recruited,and the mean levels of uric acid,body mass index,systolic blood pres-sure,diastolic blood pressure,fasting plasma glucose,total cholesterol(TC),triglyceride,and low-density lipoprotein cholesterol(LDL-C)showed an upward trend with the increasing remnant cholesterol(RC)quarters(Ptrendduring the total 36,596 person-years follow-up,the CVD mortal-ity and all-cause mortality during an average 8.13 years of follow-up was 3.87%(95%CI:3.30%-4.43%)and 14.83%(95%CI:13.79%-15.86%)with 174 CVD death participants and 667 all-cause death *** adjusting for confounders,the higher level of TC(HR=0.854,95%CI:0.730-0.997),LDL-C(HR=0.817,95%CI:0.680-0.982)and HDL-C(HR=0.443,95%CI:0.271-0.724)were associated with lower risk of CVD death,and the higher level of HDL-C(HR=0.637,95%CI:0.501-0.810)were associated with lower risk of all-cause *** higher level of RC(HR=1.276,95%CI:1.010-1.613)increase the risk of CVD ***-pared with the normal lipid group,TC≥6.20 mmol/L group and LDL-C≥4.10 mmol/L group were no longer associated with lower risk of CVD death,while RC≥0.80 mmol/L group was still associated with higher risk of CVD *** normal lipid gr-oup,the higher levels of TC,LDL-C and HDL-C were related with lower CVD *** In community older adults,higher levels of TC

关键词： mortality cholesterol hazard

Spatial Distribution of Parvalbumin-Positive Fibers in the Mouse Brain and Their Alterations in Mouse Models of Temporal Lobe Epilepsy and Parkinson’s Disease

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Neuroscience Bulletin 2023年第11期39卷 1683-1702页

作者： Changgeng Song yan Zhao Jiajia Zhang Ziyi Dong Xin Kang Yuqi pan Jinle du Yiting Gao Haifeng Zhang Ye Xi Hui Ding Fang Kuang wenting wang Ceng Luo Zhengping Zhang Qinpeng Zhao Jiazhou yang wen jiang Shengxi Wu Fang Gao Department of Neurobiology and Institute of Neurosciences School of Basic MedicineFourth Military Medical UniversityXi’an710032China Department of Neurology Xijing HospitalFourth Military Medical UniversityXi’an710032China National Translational Science Center for Molecular Medicine Department of Cell BiologyFourth Military Medical UniversityXi’an710032China Department of Spinal Surgery Honghui HospitalXi’an Jiaotong University College of MedicineXi’an710054China The Medical College of yan’an University Yan’an716000China

Parvalbumin interneurons belong to the major types of GABAergic *** the distribution and pathological alterations of parvalbumin interneuron somata have been widely studied,the distribution and vulnerability of the neurites and fibers extending from parvalbumin interneurons have not been detailly *** the Cre recombinase-reporter system,we visualized parvalbumin-positive fibers and thoroughly investigated their spatial distribution in the mouse *** found that parvalbumin fibers are widely distributed in the brain with specific morphological characteristics in different regions,among which the cortex and thalamus exhibited the most intense parvalbumin *** regions such as the striatum and optic tract,even long-range thick parvalbumin projections were ***,in mouse models of temporal lobe epilepsy and Parkinson’s disease,parvalbumin fibers suffered both massive and subtle morphological *** study provides an overview of parvalbumin fibers in the brain and emphasizes the potential pathological implications of parvalbumin fiber alterations.

关键词： alterations epilepsy fibers