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Additive manufactured osseointegrated screws with hierarchical design

Bio-Design and Manufacturing 2024年第2期7卷 206-235页

作者： Wenbo yang Hao Chen Haotian Bai Yifu Sun Aobo Zhang yang liu Yuchao Song qing Han Jincheng Wang Department of Orthopedics Second Hospital of Jilin UniversityChangchun 130022China College of Biological and Agricultural Engineering Jilin UniversityChangchun 130022China School of Materials Science and Engineering Jilin UniversityChangchun 130022China

Bone screws are devices used to fix implants or bones to ***,conventional screws are mechanically fixed with thread and often face long-term failure due to poor *** improve osseointegration,screws are evolving from solid and smooth to porous and *** manufacturing(AM)offers a high degree of manufacturing freedom,enabling the preparation of predesigned screws that are porous and *** paper provides an overview of the problems currently faced by bone screws:long-term loosening and screw ***,advances in osseointegrated screws are summarized hierarchically(sub-micro,micro,and macro).At the sub-microscale level,we describe surface-modification techniques for enhancing *** the micro level,we summarize the micro-design parameters that affect the mechanical and biological properties of porous osseointegrated screws,including porosity,pore size,and pore *** addition,we highlight three promising pore shapes:triply periodic minimal surface,auxetic structure with negative Poisson ratio,and the Voronoi *** the macro level,we outline the strategies of graded design,gradient design,and topology optimization design to improve the mechanical strength of porous osseointegrated ***,this paper outlines advances in AM technology for enhancing the mechanical properties of porous osseointegrated *** osseointegrated screws with hierarchical design are expected to provide excellent long-term fixation and the required mechanical strength.

关键词： Bone screws Additive manufacturing Architecture design Surface modification

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High-resolution neutronics model for ^(238)Pu production in high-flux reactors

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Nuclear Science and Techniques 2024年第5期35卷 226-236页

作者： qing-Quan Pan qing-Fei Zhao Lian-Jie Wang Bang-yang Xia Yun Cai Jin-Biao Xiong Xiao-Jing liu School of Nuclear Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610200China

We proposed and compared three methods(filter burnup,single energy burnup,and burnup extremum analysis)to build a high-resolution neutronics model for 238Pu production in high-flux *** filter burnup and single energy burnup methods have no theoretical approximation and can achieve a spectrum resolution of up to~1 eV,thereby constructing the importance curve and yield curve of the full energy *** burnup extreme analysis method combines the importance and yield curves to consider the influence of irradiation time on production efficiency,thereby constructing extreme *** three curves,which quantify the transmutation rate of the nuclei in each energy region,are of physical significance because they have similar distributions.A high-resolution neutronics model for ^(238)Pu production was established based on these three curves,and its universality and feasibility were *** neutronics model can guide the neutron spectrum optimization and improve the yield of ^(238)Pu by up to 18.81%.The neutronics model revealed the law of nuclei transmutation in all energy regions with high spectrum resolution,thus providing theoretical support for high-flux reactor design and irradiation production of ^(238)Pu.

关键词： ^(238)Pu Neutronics model High-flux reactor Spectrum resolution Spectrum optimization

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Left univentricular pacing for cardiac resynchronization therapy using rate-adaptive atrioventricular delay

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Journal of Geriatric Cardiology 2017年第2期14卷 118-126页

作者： Li-Jin PU Yu WANG Lu-Lu ZHAO Tao GUO Shu-Min LI Bao-Tong HUA Ping yang Jun yang Yan-Zhou LU liu-qing yang Ling ZHAO Hai-Yun LUO Department of Cardiology the First Affiliated Hospital of Kunming Medical University Kunming Yunnan China Institute of Cardiovascular Diseases of Yunnan Province Kunming Yunnan China Cardiovascular Division and Lillehei Heart Institute University of Minnesota Minnesota USA Department of Pharmacology College of Basic Medicine Kunming Medical University Kunming Yunnan China

Objective To evaluate left univentricular （LUV） pacing for cardiac resynchronization therapy （CRT） using a rate-adaptive atrioven- tricular delay （RAAVD） algorithm to track physiological atrioventricular delay （AVD）. Methods A total of 72 patients with congestive heart failure （CHF） were randomized to RAAVD LUV pacing versus standard biventricular （BiV） pacing in a 1 ： 1 ratio. Echocardiography was used to optimize AVD for both groups. The effects of sequential BiV pacing and LUV pacing with optimized A-V （right atrio-LV） delay using an RAAVD algorithm were compared. The standard deviation （SD） of the S/R ratio in lead VI at five heart rate （HR） segments （Rs/R-SD5）, defined as the ＂tracking index,＂ was used to evaluate the accuracy of the RAAVD algorithm for tracking physiological AVD. Results TheQRS complex duration （132 ± 9.8 vs. 138± 10ms, P 〈 0.05）, the time required for optimization （21 ±5 vs. 50±8min, P〈 0.001）, the mitral regurgitant area （1.9 ± 1.1 vs. 2.5 ± 1.3 em2, P 〈 0.05）, the interventricular mechanical delay time （60.7 ± 13.3 ms vs. 68.3 ± 14.2 ms, P 〈 0.05）, and the average annual cost （13,200 ± 1000 vs. 21,600 ± 2000 RMB, P 〈 0.001） in the RAAVD LUV pacing group were significantly less than those in the standard BiV pacing group. The aortic valve velocity-time integral in the RAAVD LUV pacing group was greater than that in the standard BiV pacing group （22.7 ± 2.2 vs. 21.4 ± 2.1 cm, P 〈 0.05）. The Rs/R-SD5 was 4.08 ± 1.91 in the RAAVD LUV pacing group, and was significantly negatively correlated with improved left ventricular ejection fraction （LVEF）（ALVEF, Pearson＇s r = -0.427, P = 0.009）, and positively correlated with New York Heart Association class （Spearman＇s r - 0.348, P 0.037）. Conclusions RAAVD LUV pacing is as effective as standard BiV pacing, can be more physiological than standard BiV pacing, and can de- crease the average annual cost of CRT.

关键词： Cardiac resynchronization therapy Congestive heart failure Left univentricular pacing Rate adaptive atrio-ventricular delay

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南昌市2017-2022年鼠类种群密度与季节消长监测分析

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中国媒介生物学及控制杂志 2024年第1期35卷 32-35页

作者：付仁龙陈飞刘仰青陶卉英马红梅范义兵杨树传染病预防控制国家重点实验室研究基地江西省卫生健康新发传染病病原学诊断及基因组学重点实验室南昌市疾病预防控制中心江西南昌330038

目的了解南昌市鼠种构成、鼠密度、不同生境鼠密度变化及季节消长情况,为南昌市科学制定鼠类防控方案提供依据。方法 2017-2022年设置城镇居民区、农村自然村和特殊行业3种监测生境,采用夹夜法进行鼠密度监测,采用描述性统计方法分析... 详细信息

目的了解南昌市鼠种构成、鼠密度、不同生境鼠密度变化及季节消长情况,为南昌市科学制定鼠类防控方案提供依据。方法 2017-2022年设置城镇居民区、农村自然村和特殊行业3种监测生境,采用夹夜法进行鼠密度监测,采用描述性统计方法分析南昌市3类不同生境的鼠种构成及鼠密度季节消长等。采用Excel 2021软件整理数据,SPSS 26.0软件用于分析南昌市3类不同生境的鼠种构成及鼠密度季节消长等。描述性方法对监测数据进行统计分析,不同年份和不同生境的鼠密度比较采用χ^(2)检验。结果 2017-2022年南昌市共布放有效鼠夹104 121夹次,捕获鼠类548只,平均鼠密度为0.53%,6年间鼠密度差异有统计学意义(χ^(2)=34.857,P特殊行业(0.45%)>城镇居民区(0.30%)(χ^(2)=304.340,P<0.001)。城镇居民区和农村自然村的优势鼠种为褐家鼠和黄胸鼠,小家鼠在特殊行业占优势(47.47%)。褐家鼠在特殊行业和农村自然村的构成比呈下降趋势,黄胸鼠在城镇居民区的构成比先升后降,而在特殊行业和农村自然村则总体呈上升趋势;小家鼠在3类不同生境的构成比总体均呈上升趋势。结论2017-2022年南昌市不同年份间鼠密度差异较大,鼠密度随季节变化呈双峰分布,农村自然村鼠密度较高,应针对不同生境鼠种的变化采取针对性的防制措施以降低鼠密度及鼠源疾病风险。

关键词：鼠类密度鼠种构成季节消长监测

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A novel phenotypic assay of hepatitis B virus polymerase with extensive site-specific mutagenesis

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Virologica Sinica 2017年第2期32卷 167-170页

作者： ya liu ying-ying luo xue-fei cai quan-xin long chun-yang gan liu-qing yang haitao guo ai-long huang wen-lu zhang jie-li hu institute for viral hepatitis key laboratory of molecular biology on infectious diseasesministry of educationthe second affiliated hospital of chongqing medical universityChongqing 400016China department of microbiology and immunology indiana university school of medicine indianapolis46202 USA collaborative innovation center for diagnosis and treatment of infectious diseases(ccid) Hangzhou 310058China

Dear Editor,A common reason for drug failure during long-term treatment of chronic hepatitis B with nucleot(s)ide analogues(NUCs)is the emergence of drug resistance(Das et al.,2001).Most primary NUCs-resistant mutatio... 详细信息

关键词： In HBVDNA FSR A novel phenotypic assay of hepatitis B virus polymerase with extensive site-specific mutagenesis LAM

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Inhibiting shuttle effect of lithium polysulfides by double metal selenides for high-performance lithium-sulfur batteries

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Rare Metals 2024年第6期43卷 2546-2559页

作者： Lei Li Xue-Jing yang Yi-yang Li Bo Jin Hui liu Meng-yang Cui Dong-Bo Guan Xing-You Lang qing Jiang Key Laboratory of Automobile Materials Ministry of Educationand College of Materials Science and EngineeringJilin UniversityChangchun 130022China

Lithium-sulfur batteries(LSBs)have attracted the attention of more and more researchers due to the advantages of high energy density,environmental friendliness,and low production ***,the low electronic conductivity of active material and shuttling effect of lithium polysulfides(LiPSs)limit the commercial development of *** solve these problems,we design a core-shell composite with nitrogen-doped carbon(NC)and two types of selenides(FeSe_(2)-NC@ZnSe-NC).The FeSe_(2)-NC@ZnSe-NC has a strong adsorption capacity,and can effectively adsorb *** the same time,it also effectively alleviates the shuttling effect of LiPSs,and improves the utilization of the active substance during the charge/discharge reaction *** mechanism involved in FeSe_(2)-NC@ZnSe-NC is demonstrated by both experiments and density-functional theory(DFT)*** electrochemical test results indicate that LSB with S/FeSe_(2)-NC@ZnSe-NC delivers an initial discharge capacity of 1260 mAh·g^(-1)at *** after 500 cycles at 1C,the capacity decay rate per cycle is 0.031%,and the capacity retention rate is 85%.The FeSe_(2)-NC@ZnSe-NC core-shell structure verifies a rational strategy to construct an electrode material for high-performance LSBs.

关键词： Lithium-sulfur batteries Shuttling effect Metal selenide Nitrogen-doped carbon Lithium polysulfides

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Electricity-Heat-Based Integrated Demand Response Considering Double Auction Energy Market with Multi-Energy Storage for Interconnected Areas

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1688-1700页

作者： Dan Wang Deyu Huang qing'e Hu Hongjie Jia Bo liu yang Lei Key Laboratory of Smart Grid of Ministry of Education Tianjin UniversityTianjin 300072China Key Laboratory of Smart Energy&Information Technology of Tianjin Municipality Tianjin 30072China

With development of integrated energy systems and energy markets,transactive energy has received increasing attention from society and academia,and realization of energy distribution and integrated demand response through market transactions has become a current research *** on optimized operation of a distributed energy station as a regional energy supply center is of great significance for improving flexibility and reliability of the *** on retail-side energy trading market,this study first establishes a framework of combined electric and heating energy markets and analyses a double auction market mechanism model of interconnected distributed energy *** study establishes a mechanism model of energy market participants,and establishes the electric heating combined market-clearing model to maximize global surplus considering multi-energy ***,in the case study,a typical user energy consumption scenario in winter is selected,showing market-clearing results and demand response effects on a typical *** of transmission line constraints,energy supply equipment capacity,and other factors on clearing results and global surplus are compared and analyzed,verifying the effects of the proposed method on improving global surplus,enhancing interests of market participants and realizing coordination and optimal allocation of both supply and demand resources through energy complementarity between regions.

关键词： Double auction energy market integrated energy system interconnected energy stations multi-energy storage

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Resource allocation for physical-layer security in OFDMA downlink with imperfect CSI

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Frontiers of Information Technology & Electronic Engineering 2018年第3期19卷 398-408页

作者： Wei yang Jing MAO Chen CHEN Xiang CHENG liu-qing yang Hai-ge XIANG State Key Laboratory of Advanced Optical Communication Systems and Networks Peking University Department of Electrical & Computer Engineering Colorado State University

We investigate the problem of resource allocation in a downlink orthogonal frequency-division multiple access （OFDMA） broadband network with an eavesdropper under the condition that both legitimate users and the eavesdropper are with imperfect channel state information （CSI）. We consider three kinds of imperfect CSI：（1） noise and channel estimation errors, （2） feedback delay and channel prediction, and （3） limited feedback channel capacity, where quantized CSI is studied using rate-distortion theory because it can be used to establish an information-theoretic lower bound on the capacity of the feedback channel. The problem is formulated as joint power and subcarrier allocation to optimize the maximum-minimum （max-min） fairness criterion over the users＇ secrecy rate. The problem considered is a mixed integer nonlinear programming problem. To reduce the complexity, we propose a two-step suboptimal algorithm that separately performs power and subcarrier allocation. For a given subcarrier assignment, optimal power allocation is achieved by developing an algorithm of polynomial computational complexity. Numerical results show that our proposed algorithm can approximate the optimal solution.

关键词： Resource allocation Orthogonal frequency-division multiple access(OFDMA) Imperfect channel state information(CSI) Physical layer security

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Reduced Spring Precipitation Bias and Associated Physical Causes over South China in FGOALS-f3 Climate Models:Experiments with the Horizontal Resolutions

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Journal of Meteorological Research 2024年第4期38卷 784-804页

作者： Peng ZI Yimin liu Jiandong LI Ruowen yang Bian HE qing BAO Department of Atmospheric Science Yunnan UniversityKunming 650504 State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029

Considerable spring precipitation occurs over South China(SC),a region that is adjacent to large-scale Asian topography and *** reasonable simulation is crucial for improving regional climate *** study investigates spring precipitation biases over SC and their possible causes in atmosphere-only and coupled Flexible Global Ocean–Atmosphere–Land System finite-volume version 3(FGOALS-f3) models with different horizontal *** performance of spring precipitation simulation over SC varies across different FGOALS-f3 model versions,with the best reproducibility in the high-resolution coupled model(25 km).In the low-resolution atmosphere-only model(100–125 km),the precipitation dry bias over SC is closely linked to overestimated surface sensible forcing over the eastern Tibetan Plateau(TP),which weakens the subtropical anticyclone over the western Pacific(SAWP) through regional circulation *** contrast,the high-resolution atmosphere-only model further amplifies surface thermal forcing in the Asian continents,causing intensified land–sea thermal contrast between the Southeast Asian continents and western Pacific,enhanced southerly winds and SAWP,and increased water vapor transport into ***,the reduced middle–high level cold bias over 10°–30°N in the high-resolution atmosphere-only model intensifies the East Asian westerly jet and ascent over SC,leading to enhanced spring precipitation *** high-resolution coupled model simulation not only reduces sea surface cold bias over the Bay of Bengal,thus intensifying the Indian–Burma trough and strengthening low-level water vapor transport into SC,but also enhances ascent over *** a result,the high-resolution coupled model better reproduces the magnitude and pattern of spring precipitation over SC than its atmosphere-only *** with low-resolution models,the domain-mean spring precipitation dry bias decreases by 11.2% over SC in the high-resolution atmosphere-only mod

关键词： South China spring precipitation high resolution Flexible Global Ocean–Atmosphere–Land System finite-volume version 3(FGOALS-f3)models simulation

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The validity of serum ferritin levels in predicting cardiovascular events of metabolic dysfunction-associated steatotic liver disease patients may need more consideration

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Hepatobiliary Surgery and Nutrition 2024年第4期13卷 755-756页

作者： Jie yang qing liu Jie Li Chao Sun Department of Gastroenterology Tianjin Medical University General Hospital Airport HospitalTianjinChina Department of Gastroenterology and Hepatology Tianjin Medical University General HospitalTianjinChina Department of Infectious Diseases Nanjing Drum Tower HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjingChina

We read with great interest the informative study by Armandi et al.,which shed light on the potential role of serum ferritin in predicting the long-term prognosis of patients with metabolic dysfunction-associated steatotic liver disease(1).However,there remain certain facets requiring in-depth investigation and *** of all,the study found that integrating stepwise increased ferritin thresholds(215.5 and 272µg/L)into predictive models can improve the performance of fibrosis-4(FIB-4)and Non-Alcoholic Fatty Liver Disease Fibrosis Score(NFS)in the longitudinal risk assessment of liver-related events and overall ***,it has been suggested that metabolic hyperferritinaemia(MHF)appears to exhibit a male predominance(2,3).Since the study primarily comprised male participants(65%),it raises the query of whether the ferritin threshold based on the entire population can accurately predict risks within female ***,a sex-specific analysis is warranted to ensure a more precise evaluation.

关键词： Metabolic dysfunction-associated steatotic liver disease(MASLD) serum ferritin cardiovascular events

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