检索结果-南通市图书馆

New perspective on the natural course of chronic HBV infection

Frontiers of Medicine 2014年第2期8卷 129-134页

作者： yong-yuan zhang Ke-Qin Hu Zhongping Duan HB Vtech LLC 13901 Lullaby RD Germantown MD 20874 USA Division of Gastroenterology and Hepatology University of California Irvine School of Medicine Orange CA 92868 USA You An Hospital Capital Medical University Beijing 100069 China

Chronic hepatitis B virus （HBV） infection is a significant threat to public health and an enormous burden on society. Mechanisms responsible for chronic HBV infection remain poorly understood. A better understanding of the natural course of chronic HBV infection may shed new light on the mechanisms underlying this disease and help in designing new antiviral strategies. Natural course of chronic HBV infection is conventionally viewed as an uninterrupted process that is usually marked by HBV e antigen （HBeAg） seroconversion or characterized by different phases associated with assumed host responses to HBV infection. However, none of these descriptions captures or highlights the core events that determine the natural course of chronic HBV infection. In this review, we briefly present the current knowledge on this subject and explain the significance and implication of events that occur during infection. A pre-core mutant becomes predominant in the viral population following elimination of the wild-type virus in duck hepatitis B virus-chronically infected animals. The coupled events in which first there is viral clearance that clears wild-type virus and then there is the reinfection of wild-type virus cleared livers with mutant virus are highly relevant to understanding of the natural course of chronic HBV infection under both treated and untreated conditions. In our new perspective, a general natural course of chronic HBV infection comprises cycles of viral clearance and reinfection, and such cycles prolong the chronic HBV infection course. Reviewing published data on the natural course of chronic HBV infection can reduce the possibility of missing important points in the initial data interpretation.

关键词： hepatitis B virus chronic HBV infection natural course hepatitis B seroconversion

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Resource Allocation for Cognitive Network Slicing in PD-SCMA System Based on Two-Way Deep Reinforcement Learning

引用

China Communications 2024年第6期21卷 53-68页

作者： zhang Zhenyu zhang yong yuan Siyu Cheng Zhenjie School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China Beijing Key Laboratory of Work Safety Intelligent Monitoring(Beijing University of Posts and Telecommunications) Beijing 100876China

In this paper,we propose the Two-way Deep Reinforcement Learning(DRL)-Based resource allocation algorithm,which solves the problem of resource allocation in the cognitive downlink network based on the underlay *** users(SUs)in the cognitive network are multiplexed by a new Power Domain Sparse Code Multiple Access(PD-SCMA)scheme,and the physical resources of the cognitive base station are virtualized into two types of slices:enhanced mobile broadband(eMBB)slice and ultrareliable low latency communication(URLLC)*** design the Double Deep Q Network(DDQN)network output the optimal codebook assignment scheme and simultaneously use the Deep Deterministic Policy Gradient(DDPG)network output the optimal power allocation *** objective is to jointly optimize the spectral efficiency of the system and the Quality of Service(QoS)of *** results show that the proposed algorithm outperforms the CNDDQN algorithm and modified JEERA algorithm in terms of spectral efficiency and QoS ***,compared with the Power Domain Non-orthogonal Multiple Access(PD-NOMA)slices and the Sparse Code Multiple Access(SCMA)slices,the PD-SCMA slices can dramatically enhance spectral efficiency and increase the number of accessible users.

关键词： cognitive radio deep reinforcement learning network slicing power-domain non-orthogonal multiple access resource allocation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Perovskite quantum laser with enhanced population inversion driven by plasmon-induced hot electron transfer under potential shift polarization conditions

引用

Photonics Research 2024年第5期12卷 986-994页

作者： yong PAN LIJIE WU yuan zhang YIHAO zhang JIE XU HAIXIA XIE JIANGUO CAO College of Science Xi'an University of Architecture and TechnologyXi'an 710055China

The hot electron transfer resulting in fluorescence enhancement is significantly meaningful for theory and experiment of the study on photoelectric ***,the laser emission based on direct hot electron transfer is difficult to realize because of the low transfer *** achieve a laser with a new-generation mechanism based on hot electron transfer,the photoelectric co-excitation is proposed for improving the efficiency of hot electron *** lasing behavior at 532 nm is realized with a threshold of 5 kw cm^(-2)and 1μA,which can be considered as the hot electron transfer resulting in population inversion ***,the lasing output power is 0.3 *** hot electrons transfer process was described via the transient absorption spectrum according to the improved ground-state bleaching and excited-state absorption signal in device *** comparison with the optical pump only,the quantum efficiencies of hot electron generation(HEG)and hot electron transfer(HET)were increased~31%and 31%,*** importantly,a triple gain mode coupling device including local surface plasmon,hot electron transfer,and array oscillation was *** modes of population inversion enhancement are *** study can provide theoretical and experimental reference for the research of hot electron lasers and devices.

关键词： polarization pump transfer

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Changes in global land surface frozen ground and freeze-thaw processes during 1950-2020 based on ERA5-Land data

引用

Advances in Climate Change Research 2024年第2期15卷 265-274页

作者： yong YANG Ren-Sheng CHEN yong-Jian DING Hong-yuan LI zhang-Wen LIU Qilian Alpine Ecology and Hydrology Research Station Key Laboratory of Ecological Safety and Sustainable Development in Arid LandsNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 73000China State Key Laboratory of Cryospheric Sciences Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 73000China Shandong Provincial Key Laboratory of Water and Soil Conservation and Environmental Protection College of Resources and EnvironmentLinyi UniversityLinyi 276000China

Frozen ground(FG)plays an important role in global and regional climates and environments through changes in land freeze-thaw processes,which have been conducted mainly in different ***,the changes in land surface freeze-thaw processes under climate change on a global scale are still *** on ERA5-Land hourly land skin temperature data,this study evaluated changes in the global FG area,global land surface first freeze date(FFD),last freeze date(LFD)and frost-free period(FFP)from 1950 to *** results show that the current FG areas(1991-2020 mean)in the Northern Hemisphere(NH),Southern Hemisphere(SH),and globe are 68.50×10^(6),9.03×10^(6),and 77.53×10^(6)km^(2),which account for 72.4%,26.8%,and 60.4%of the exposed land(excluding glaciers,ice sheets,and water bodies)in the NH,SH and the globe,respectively;further,relative to 1951-1980,the FG area decreased by 1.9%,8.8%,and 2.8%,*** FG at lower latitudes degrades to intermittently FG,and intermittently FG degrades to non-frozen ground,which caused the global FG boundary to retreat to higher latitudes from 1950 to *** annual FG areas in the NH,SH,and globe all show significant decreasing trends(p<0.05)from 1950 to 2020 at-0.32×10^(6),-0.22×10^(6),and-0.54×10^(6)km^(2)per decade,*** FFP prolongation in the NH is mainly influenced by LFD advance,while in the SH it is mainly controlled by FFD *** prolongation trend of FFP in the NH(1.34 d per decade)is larger than that in the SH(1.15 d per decade).

关键词： Frozen ground Freeze-thaw processes Frost-free period First freeze date Global warming

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A hiddenly high hepatitis C virus related liver disease burden among Chinese patients with non-liver disease complaints: A hospital based study from 2013 to 2017

引用

Asian Pacific Journal of Tropical Medicine 2018年第2期11卷 171-176页

作者： Hua-Ping Huang Guo-Sheng yuan Yu-Chen Zhou Cheng-Guang Hu Jun-Wei Liu Shuai yuan Yu-Rong Qiu Yi-Ping Li yong-yuan zhang yuan-Ping Zhou Department of Infectious Diseases and Hepatology Unit Nanfang HospitalSouthern Medical University Department of Respiratory Diseases The First Affiliated Hospital of Hainan Medical University Department of Hepatobiliary Surgery Nanfang HospitalSouthern Medical University Laboratory Medicine Center Nanfang HospitalSouthern Medical University Institute of Human Virology and Key Laboratory of Tropical Disease Control of Ministry of Education Zhongshan School of MedicineSun Yat-sen University HBVtech

Objective: To determine the frequency of anti-HCV antibody positivity in patients with nonliver disease complaints, to explore whether anti-HCV positive patients had been properly advised and visited hepatologists for further assessments, and to investigate their clinical characteristics as well as the HCV treatment ***: A hospital based survey of nonliver disease patients with anti-HCV positive and their attending physicians was conducted to determine: *** the patients adequately advised of the implication of anti-HCV positive finding; *** what extent the patients were aware of potential chronic liver disease associated with HCV infection and whether they sought for further assessments and care of ***: A total of 295 294 non-liver disease patients were tested for anti-HCV antibody, and 2 778 of them were found to be positive(0.94%).However, only 45.10%(1 253/2 778) of the anti-HCV antibody(+) patients were referred to hepatologists and received HCV RNA *** addition, 34.10%(312/915) and 1.42%(13/915) of them had already advanced to cirrhosis and hepatocellular carcinoma(HCC), *** analysis showed that the patients who declined antiviral therapy were older, with lower education and lower income, possessed poorer knowledge on the risk of chronic hepatitis C, and had more severe liver ***, 65% of the surveyed physicians did not know the genotype-guided treatment duration suggested by the ***, 22% of the surveyed physicians did not know the standard assays for the diagnosis of HCV ***: Our findings highlight the challenge and hidden enormous burden of chronic HCV infection among patients with non-liver disease complaints in China.

关键词： China HCV Hepatitis C antibody Diagnosis Treatment status Survey

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Numerical Simulation on Radon Retardation Behavior of Covering Floats in Radon-Containing Water

引用

Biomedical and Environmental Sciences 2024年第4期37卷 406-417页

作者： LIU Shu yuan zhang Li YE yong Jun DING Ku Ke National Institute for Radiological Protection Chinese Center for Disease Control and PreventionBeijing 100088China Office for Public Health Management Chinese Center for Disease Control and PreventionBeijing 102206China Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy University of South ChinaHengyang 421001HunanChina

Objective This study aimed to efficiently reduce the release of radon from water bodies to protect the *** Based on the sizes of the experimental setup and modular float,computational fluid dynamics(CFD)was used to assess the impact of the area coverage rate,immersion depth,diffusion coefficient,and radon transfer velocity at the gas–liquid interface on radon migration and exhalation of radon-containing *** on the numerical simulation results,an estimation model for the radon retardation rate was *** effectiveness of the CFD simulation was evaluated by comparing the experimental and simulated variation values of the radon retardation rate with the coverage area *** The effect of radon transfer velocity on radon retardation in water bodies was minor and insignificant according to the appropriate value;therefore,an estimation model of the radon retardation rate of the coverage of a radon-containing water body was constructed using the synergistic impacts of three factors:area coverage rate,immersion depth,and diffusion *** deviation between the experimental and simulated results was<4.3%.Conclusion Based on the numerical simulation conditions,an estimation model of the radon retardation rate of covering floats in water bodies under the synergistic effect of multiple factors was obtained,which provides a reference for designing covering floats for radon retardation in radoncontaining water.

关键词： Radon-containing water Radon retardation rate CFD Coverage experiment Optimized design

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Absence of metallicity and bias-dependent resistivity in low-carrier-density EuCd_(2)As_(2)

引用

Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 119-125页

作者： Yuxiang Wang Jianwen Ma Jian yuan Wenbin Wu yong zhang Yicheng Mou Jiaming Gu Peihong Cheng Wu Shi Xiang yuan Jinglei zhang Yanfeng Guo Cheng zhang State Key Laboratory of Surface Physics and Institute for Nanoelectronic Devices and Quantum Computing Fudan UniversityShanghai 200433China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200241China Anhui Province Key Laboratory of Condensed Matter Physics at Extreme Conditions High Magnetic Field Laboratory of the Chinese Academy of SciencesHefei 230031China School of Physics and Electronic Science East China Normal UniversityShanghai 200241China zhangjiang Fudan International Innovation Center Fudan UniversityShanghai 201210China ShanghaiTech Laboratory for Topological Physics Shanghai 201210China

EuCd_(2)As_(2)was theoretically predicted to be a minimal model of Weyl semimetals with a single pair of Weyl points in the ferromagnet ***,the heavily p-doped Eu Cd_(2)As_(2)crystals in previous experiments prevent direct identification of the semimetal ***,we present a comprehensive magneto-transport study of high-quality Eu Cd_(2)As_(2)crystals with ultralow bulk carrier density(10^(13)cm^(-3)).In contrast to the general expectation of a Weyl semimetal phase,Eu Cd_(2)As_(2)shows insulating behavior in both antiferromagnetic and ferromagnetic states as well as surface-dominated conduction from band ***,the application of a dc bias current can dramatically modulate the resistance by over one order of magnitude,and induce a periodic resistance oscillation due to the geometric *** nonlinear transport results from the high nonequilibrium state induced by an electrical field near the band *** results suggest an insulating phase in Eu Cd_(2)As_(2)and put a strong constraint on the underlying mechanism of anomalous transport properties in this system.

关键词： magnetic Weyl semimetal quantum transport Hall effect nonlinear resistivity

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Large-Scale and Reversible Synthesis of Bright Upconversion Crystals with Almost 100%Yield by a Minimalist Method for Recyclable Application

引用

CCS Chemistry 2024年第6期6卷 1512-1522页

作者： Pengpeng Lei yuan Liang Pengye Du yong zhang Hongjie zhang State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022 University of Science and Technology of China Hefei 230026 Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou 341000 Department of Biomedical Engineering Faculty of EngineeringNational University of SingaporeSingapore 117583 Department of Chemistry Tsinghua UniversityBeijing 100084

Upconversion luminescence(UCL)materials have the potential for many applications due to their unique optical *** technical challenges such as complex synthesis with low yield and nondegradability need to be addressed for practical ***,we report for the first time a minimalist method for large-scale synthesis of Cs_(2)NaErCl_(6)UCL crystals with almost 100%yield,simply by dissolving metal chlorides in water and then drying,referred to as the“dissolve-dry”***_(2)NaErCl_(6)crystals produced under such mild conditions exhibited bright UCL at either 808 or 980 nm *** was achieved through an excited state absorption process,and the excellent performance was mainly attributed to the large unit cells of the crystals and the long lifetime of Er^(3+)excited energy ***,the synthesis was reversible and could be scaled up unlimitedly,making it suitable for industrial applications,with recyclable *** recyclable application of Cs_(2)NaErCl_(6)crystals as a luminescent medium in near-infrared light-emitting diode excitable upconversion devices was demonstrated based on its excellent *** work not only provides a new strategy for large-scale synthesis of UCL crystals but also demonstrates the recyclability of this material and its related applications.

关键词： rare earth upconversion reversible synthesis minimalist method application

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Pyrolysis Empirical Modeling of Polyester Glass Fiber Reinforced Plastics Using Sestak-Berggren Model Method

引用

Journal of Thermal Science 2024年第2期33卷 725-738页

作者： NAN Wei JI Wenhui yuan Yanping yuan Zhongyuan SUN yong School of Mechanical Engineering Southwest Jiaotong UniversityChengdu610031China CRRC Changchun Railway Vehicles Co. LtdChangchun130062China

Polyester Glass Fiber Reinforced Plastic(Polyester GFRP),a thermosetting plastic comprised of glass fiber and polyester polymer compounds,is extensively utilized in high-speed *** its pyrolysis mechanism is crucial as it significantly influences the combustion characteristics and fire safety ***,kinetic research on polyester GFRP primarily focuses on employing the Coats-Redfern method to derive a theoretical kinetic ***,the pyrolysis process of polyester GFRP is complex and the aforementioned theoretical model fails to accurately describe the pyrolysis ***,this study seeks to utilize the Sestak and Berggren(SB) model as a methodological approach to reveal the complex reaction mechanism during the pyrolysis *** on thermogravimetric analysis,the entire pyrolysis process of polyester GFRP is divided into two primary ***,model-free methods are employed to ascertain the activation energy and pre-exponential *** results show that the fitted empirical models of the two main pyrolysis stages are f(α)=(1-α)^(1.47)[-ln(1-α)]^(1.50) and f(α)=(1-α)^(1.77)[-ln(1-α)]^(1.72),*** predicted results are in good agreement with experimental data under different heating rates,which indicates that the empirical model can sufficiently describe the pyrolysis process of polyester GFRP.

关键词： polyester GFRP model-fitting methods empirical models pyrolysis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Recent Progress and Regulation Strategies of Layered Materials as Cathode of Aqueous Zinc-Ion Batteries

引用

Energy & Environmental Materials 2024年第3期7卷 18-35页

作者： yuan yuan Si Wu Xiaoxue Song Jin yong Lee Baotao Kang School of Chemistry and Chemical Engineering University of Jinan Department of Chemistry Sungkyunkwan University Shandong Hi-Speed Engineering Test Co. Ltd.

Aqueous zinc-ion batteries （ZIBs） have shown great potential in the fields of wearable devices,consumer electronics,and electric vehicles due to their high level of safety,low cost,and multiple electron transfer. The layered cathode materials of ZIBs hold a stable structure during charge and discharge reactions owing to the ultrafast and straightforward （de）intercalation-type storage mechanism of Zn2+ions in their tunable interlayer spacing and their abilities to accommodate other guest ions or ***,the challenges of inadequate energy density,dissolution of active materials,uncontrollable byproducts,increased internal pressure,and a large de-solvation penalty have been deemed an obstacle to the development of ZIBs. In this review,recent strategies on the structure regulation of layered materials for aqueous zinc-ion energy storage devices are systematically summarized. Finally,critical science challenges and future outlooks are proposed to guide and promote the development of advanced cathode materials for ZIBs.

关键词： layered cathode materials modifying strategies structure regulation zinc-ion batteries

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：