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The circadian clock in enamel development

International Journal of Oral Science 2024年第3期16卷 371-380页

作者： Ke Wu Xiaochan Li Yunyang Bai Boon Chin Heng Xuehui Zhang Xuliang Deng Department of Geriatric Dentistry Peking University School and Hospital of StomatologyBeijingChina th Division Peking University School and Hospital of StomatologyBeijingChina Department of Dental Materials&Dental Medical Devices testing center Peking University School and Hospital of StomatologyBeijingChina National Engineering Research center of Oral biomaterials and Digital Medical Devices NMPA Key Laboratory for Dental MaterialsBeijing Laboratory of Biomedical Materials&Beijing Key Laboratory of Digital StomatologyPeking University School and Hospital of StomatologyBeijingChina Oral Translational Medicine Research center Joint Training base for Shanxi Provincial Key Laboratory in Oral and Maxillofacial Repair Reconstruction and Regeneration The First People’s Hospital of Jinzhong JinzhongChina

Circadian rhythms are self-sustaining oscillations within biological systems that play key roles in a diverse multitude of physiological *** circadian clock mechanisms in brain and peripheral tissues can oscillate independently or be synchronized/disrupted by external *** enamel is a type of mineralized tissue that forms the exterior surface of the tooth *** Retzius lines are readily observable microstructures of mature tooth enamel that indicate the regulation of amelogenesis by circadian *** enamel is formed by enamel-forming cells known as ameloblasts,which are regulated and orchestrated by the circadian clock during *** review will first examine the key roles of the circadian clock in regulating ameloblasts and *** physiological processes are involved,including gene expression,cell morphology,metabolic changes,matrix deposition,ion transportation,and ***,the potential detrimental effects of circadian rhythm disruption on enamel formation are *** rhythm disruption can directly lead to Enamel Hypoplasia,which might also be a potential causative mechanism of amelogenesis ***,future research trajectory in this field is *** is hoped that this review will inspire more intensive research efforts and provide relevant cues in formulating novel therapeutic strategies for preventing tooth enamel developmental abnormalities.

关键词： enamel crown exterior

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Temporal and Spatial Trends in HIV Positivity Rate for VCT Clinics—China,2015–2022

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China CDC weekly 2024年第1期6卷 6-11页

作者： Yi Liu Rong Su Dongmin Li Shaorong Wang Mengjie Han National center for AIDS/STD Control and Prevention Chinese Center for Disease Control and PreventionBeijingChina

Introduction:Human immunodeficiency virus(HIV)voluntary counseling and testing(VCT)clinics play a critical role in identifying and diagnosing HIV *** study aimed to describe the trend of HIV positivity rate(HPR)among Chinese VCT clinics between 2015 and ***:This study utilized data from the China Information System for Disease Control and Prevention to analyze the trend in the HPR for VCT clinics from 2015 to *** HPR was calculated by dividing the number of newly-reported HIV cases by the number of HIV tests,multiplied by 100%.To identify temporal and spatial trends in the HPR,we employed joinpoint regression analysis and the Getis-Ord hotspot ***:From 2015 to 2022,VCT clinics in China performed a total of 22,075,386 HIV tests,leading to the identification of 260,353 HIV cases,resulting in a HPR of 1.18%.The HPR consistently declined over the study period,with an average annual percent change(AAPC)of−7.5%(95%confidence interval:−12.6%,−2.2%,Ptesting.

关键词： VCT dividing Spatial

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Characteristics of the HIV/AIDS Epidemic among People Aged≥50 Years in China during 2018–2021

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Biomedical and Environmental Sciences 2024年第4期37卷 399-405页

作者： HOU Yu Shan JIN Yi Chen CAI Chang TANG Hou Lin QIN Qian Qian LYU Fan National center for AIDS/STD Control and Prevention Chinese Center for Disease Control and PreventionBeijing 102206China

Objective This study aimed to determine the current epidemiological status of PLWHA aged≥50 years in China from 2018 to *** also aimed to recommend targeted interventions for the prevention and treatment of HIV/AIDS in elderly *** Data on newly reported cases of PLWHA,aged≥50 years in China from 2018 to 2021,were collected using the *** tests and spatial analyses were also *** Between 2018 and 2021,237,724 HIV/AIDS cases were reported among patients aged≥50 years in *** main transmission route was heterosexual transmission(91.24%).Commercial heterosexual transmission(CHC)was the primary mode of transmission among males,while non-marital non-CHC([NMNCHC];60.59%)was the prevalent route in *** proportion of patients with CHC decreased over time(Z=67.716,Ptesting,treatment,and integrated behavioral interventions in high-risk populations is recommended to enhance disease detection in key regions.

关键词： HIV/AIDS Aged≥50 years China

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Systematic Elastostatic Stiffness Model of Over-Constrained Parallel Manipulators Without Additional Constraint Equations

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Chinese Journal of Mechanical Engineering 2024年第4期 271-289页

作者： Chao Yang Wenyong Yu Wei Ye Qiaohong Chen Fengli Huang College of Mechanical and Electrical Engineering Jiaxing University Zhejiang Siekon Transmission Technology Co. Ltd. National and Local Joint Engineering Research center of Reliability Analysis and testing for Mechanical and Electrical Products Zhejiang Sci-Tech University School of Computer Science and Technology Zhejiang Sci-Tech University

The establishment of an elastostatic stiffness model for over constrained parallel manipulators(PMs), particularly those with over constrained subclosed loops, poses a challenge while ensuring numerical stability. This study addresses this issue by proposing a systematic elastostatic stiffness model based on matrix structural analysis(MSA)and independent displacement coordinates(IDCs) extraction techniques. To begin, the closed-loop PM is transformed into an open-loop PM by eliminating constraints. A subassembly element is then introduced, which considers the flexibility of both rods and joints. This approach helps circumvent the numerical instability typically encountered with traditional constraint equations. The IDCs and analytical constraint equations of nodes constrained by various joints are summarized in the appendix, utilizing multipoint constraint theory and singularity analysis, all unified within a single coordinate frame. Subsequently, the open-loop mechanism is efficiently closed by referencing the constraint equations presented in the appendix, alongside its elastostatic model. The proposed method proves to be both modeling and computationally efficient due to the comprehensive summary of the constraint equations in the Appendix, eliminating the need for additional equations. An example utilizing an over constrained subclosed loops demonstrate the application of the proposed method. In conclusion, the model proposed in this study enriches the theory of elastostatic stiffness modeling of PMs and provides an effective solution for stiffness modeling challenges they present.

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Research Progress on Detection Techniques of Fungicide Residues in Chinese Chives

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Agricultural Biotechnology 2024年第1期13卷 43-48页

作者： Xiuying CHEN Zhe MENG Chen DING Huihui LIU Yancheng ZHOU Jinlu LI Yanhua YAN Lei WANG Tangshan Food and Drug Comprehensive testing center Tangshan 063000China Key Laboratory of Agricultural Product Quality Evaluation and Nutrition and Health Ministry of Agriculture and Rural AffairsTangshan 063000China Hebei Agricultural Products Quality and Safety testing Technology Innovation center Tangshan 063000China Tangshan Institute of Industrial Technology for Functional Agricultural Products Tangshan 063000China Hebei North University College of Agriculture and Forestry Technology Zhangjiakou 075032China

Chinese chive is a kind of medicinal and edible plant,with many diseases,and chemical fungicides are usually used for *** order to find out the risk of pesticide residues in Chinese chives,this paper summarized relevant literatures published in recent years,and sorted out and analyzed the types of pesticides used and detection techniques of common diseases in Chinese chives.

关键词： Chinese chive Pesticide residues Fungicide Detection technique

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Nickel-iron in the second coordination shell boost single-atomicsite iridium catalysts for high-performance urea electrooxidation

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Nano Research 2024年第5期17卷 3919-3926页

作者： Xiaoyu Chen Jiawei Wan Jing Chai Liang Zhang Fang Zhang Qinghua Zhang Lin Gu Lirong Zheng Ranbo Yu Department of Physical Chemistry School of Metallurgical and Ecological EngineeringUniversity of Science and Technology BeijingBeijing 100083China State Key Laboratory of Biochemical Engineering Key Laboratory of Biopharmaceutical Preparation and DeliveryChinese Academy of SciencesInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China center for Combustion Energy School of Vehicle and MobilityState Key Laboratory of Intelligent Green Vehicle and MobilityTsinghua UniversityBeijing 100084China Analysis and testing center Beijing Institute of TechnologyBeijing 100081China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Beijing National center for Electron Microscopy and Laboratory of Advanced Materials Department of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China

Single-atom catalysts(SACs)with high catalytic activity as well as great stability are demonstrating great promotion in electrocatalytic energy conversion,which is also a big challenge to ***,we proposed a facile synthetic strategy to construct nickel-iron bimetallic hydroxide nanoribbon stabilized single-atom iridium catalysts(Ir-NiFe-OH),where the nickel-iron hydroxide nanoribbon not only can serve as good electronic conductor,but also can well stabilize and fully expose single-atom *** as catalyst for urea oxidation reaction(UOR),it exhibited excellent UOR performance that it only needed a low operated potential of 1.38 V to achieve the current density of 100 mA·cm^(-2).In-situ Fourier transform infrared spectroscopy,X-ray absorption spectrum,and density functional theory calculations proved that Ir species are active centers and the existence of both Ni and Fe in the local structure of Ir atom can optimize the d-band center of Ir species,promoting the adsorption of intermediates and desorption of products for *** hydrogen evolution reaction(HER)/UOR electrocatalytic cell demanded voltages of 1.46 and 1.50 V to achieve 50 and 100 mA·cm^(-2),respectively,which demonstrated a higher activity and better stability than those of conventional *** work opens a new avenue to develop catalysts for UORs with boosted activity and stability.

关键词： single-atom iridium coordinate structure nanoribbon urea electrooxidation

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An Improved Thermal Conductivity Measurement Scheme for Macroscopic Graphitic Films Using the Laser Flash Method

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Journal of Thermal Science 2024年第4期33卷 1480-1490页

作者： ZHANG Peijuan MING Xin LIU Yingjun WANG Xuelong SHI Hang HAO Yuanyuan LU Jiahao LIU Zheng LAI Haiwen ZHANG Ying GAO Weiwei XU Zhen GAO Chao MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringKey Laboratory of Adsorption and Separation Materials&Technologies of Zhejiang ProvinceZhejiang UniversityHangzhou310027China Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering Taiyuan030032China Special Equipment Safety Supervision and Inspection Institute of Jiangsu Province National Graphene Products Quality Inspection and Testing Center(Jiangsu)Wuxi214174China Hangzhou Gaoxi Technol Co. LtdHangzhou311113China China Academy of Aerospace Aerodynamics Beijing100074China

Achieving efficient thermal management urges to exploit high-thermal-conductivity materials to satisfy the boosted demand of heat *** is critical to adopt standardized characterization protocols to evaluate the intrinsic thermal conductivity of thermal management ***,for the most representative laser flash method,the lack of standard measurement methodology and systematic description on the thermal diffusivity and influencing factors has led to significant deviations and confusion of the thermal conduction performance in the emerging thermal management ***,the measurement error factors of thermal diffusivity by the common laser flash analyzer(LFA)are *** high-thermal-conductivity graphitic film(GF)as a typical case,the key factors are analyzed to guide the measurement protocol of related carbon-based thermal management *** basic principle of the LFA measurement,actual pre-processing conditions,instrument parameters setting,and data analysis are elaborated for accurate ***,the graphene thick films and common isotropic materials are also extended to meet various thermal measurement *** on the existing practical problems,we propose a feasible test flow to achieve a unified and standardized thermal conductivity measurement,which is beneficial to the rapid development of carbon-based thermal management materials.

关键词： thermal management graphitic film laser flash method thermal conductivity thermal diffusivity

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Numerical simulation research on multiphase flow of aviation centrifugal pump based on OpenFOAM

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Chinese Journal of Aeronautics 2024年第4期37卷 256-275页

作者： Xianwei LIU Jiangfeng FU Junjie YANG Dewen YIN Zhenhua ZHOU Huacong LI College of Power and Energy Northwestern Polytechnical UniversityXi’an 710072China Norinco Group testing and Research Institute Huayin 714200China AECC Xi’an Engine Control Technology Co.Ltd. Xi’an 710077China AECC Guizhou Honglin Aero Engine Control Technology Co.Ltd. Guiyang 550009China

This paper aims to tackle the calculation efficiency problem raised in the cavitation-flow simulation of the aviation centrifugal pump due to the fading-away interface resulting from the dissipation of numerics used in the phase-change control equation for unstructured-grid multiphase flow,and due to the limitation of flow time-step in whole flow regimes,the control equation of vapor–liquid two-phase flow considering cavitation mass transport is established firstly,modifying the momentum equation by introducing the surface tension,and adding the artificial convective flow to the phase equation to solve the numerical dissipation ***,in consideration of the local time step principle and based on the multi-dimensional general limiter algorithm with explicit solutions under the OpenFOAM platform,a solution method of steady-state VOF (Volume of Fluid) model considering cavitation two-phase change is constructed,and the feasibility of this method is verified by NACA hydrofoil and NASA flat plate ***,based on the platform developed,the cavitation performance of an aviation centrifugal pump inducer is *** research results show that the error of the calculated cavitation pressure distribution for NACA hydrofoil between the simulation test and the experimental-test is less than 5%,and the maximum error of calculated cavitation number at pump head dropping for NASA high-speed flat plate inducer between the simulation test and the experimental-test is 2.1%.The cavitation area observed in the simulation test is the same as that obtained in the high-speed photography *** on the OpenFOAM simulation method,the position of pump head dropping of the fuel centrifugal pump can be accurately *** error of the calculated cavitation number at pump head dropping between the simulation test and the experimental test is about 3.7%,showing high calculation accuracy.

关键词： Aero engine Fuel centrifugal pump Multiphase flow OpenFOAM Volume of fluid

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Effectiveness of Frequent Viral Load testing Plus Additional Interventions to Prevent HIV Transmission in Heterosexual,Serodiscordant Couples—Yunnan Province,China,2019-2021

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China CDC weekly 2024年第27期6卷 658-664,I0001-I0004页

作者： Jing Han Jian Li Yuhua Shi Chunpeng Zang Zhimin Yang Yu Han Yanling Ma Qiongli Duan Yuhua Hu Zikuang Bai Cuiyun Yang Gabriella Bulloch Yurong Mao Houlin Tang Zunyou Wu Yufen Liu National center for AIDS/STD Control and Prevention Chinese Center for Disease Control and PreventionBeijingChina Yunnan Provincial center for Disease Control and Prevention Kunming CityYunnan ProvinceChina Honghe Prefectural center for Disease Control and Prevention Honghe CityYunnan ProvinceChina Wenshan Prefectural center for Disease Control and Prevention Wenshan CityYunnan ProvinceChina Zhaotong Prefectural center for Disease Control and Prevention Zhaotong CityYunnan ProvinceChina Lincang Prefectural center for Disease Control and Prevention Lincang CityYunnan ProvinceChina Faculty of Medicine Dentistry and Health SciencesUniversity of MelbourneMelbourneVICAustralia

Summary What is already known about this topic?HIV transmission among serodiscordant couples remains a persistent issue in ***,the practice of combining counseling with antiretroviral therapies(ART)to enhance ART adhe... 详细信息

关键词： China ant discord

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Effects of temperature, particle size, and air humidity on sensibility of typical high-energetic explosives

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Journal of Measurement Science and Instrumentation 2024年第3期15卷 408-416页

作者： WU Sanzhen FANG Mingkun WU Xingliang GUO Guangfei WANG Junhong XU Sen School of Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094China China National Quality Supervision testing center for Industrial Explosive Materials Nanjing210094China

The production and utilization of high-energetic explosives often pose a range of safety hazards,with sensitivity being a key factor in evaluating these *** investigate how temperature,particle size,and air humidity affect the responsiveness of commonly used high-energetic explosives,a series of BAM(Bundesanstalt für Materialforschung und-prüfung)impact and friction sensitivity tests were carried out to determine the critical impact energy and critical load pressure of four representative high-energetic explosives(RDX,HMX,PETN and CL-20)under different temperatures,particle sizes,and air humidity *** experimental findings facilitated an examination of temperature and particle size affecting the sensitivity of high-energetic explosives,along with an assessment of the influence of air humidity on sensitivity *** results clearly indicate that high-energetic explosives display a substantial decline in critical reaction energy when subjected to micrometre-sized particles and an air humidity level of 45%at a temperature of 90℃.Furthermore,it was noted that the critical reaction energy of high-energetic explosives diminishes with an increase in temperature within 25℃−90℃.In the same vein,as the particle sizes of high-energetic explosives increase,so does the critical reaction energy for micrometre-sized *** air humidity significantly affects the sensitivity testing of high-energetic explosives,emphasizing the importance of refraining from conducting sensitivity tests in such conditions.

关键词： high-energetic explosives temperature particle size air humidity critical reaction energy

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