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Precore mutation enhances viral replication to facilitate persistent infection especially in HBeAg-negative patients

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Virologica Sinica 2024年第2期39卷 319-330页

作者： Guixin Li Danli Yang Xin Liu Ting Zhang Hui Liu jun zou Zimeng Xu Xiangmei Chen Lizhong Dai Hongsong Chen Fengmin Lu Peking University People's Hospital Peking University Hepatology InstituteBeijing Key Laboratory of Hepatitis C and Immunotherapy for Liver DiseasesBeijing International Cooperation Base for Science and Technology on NAFLD DiagnosisBeijing100044China Department of Microbiology and Infectious Disease Center School of Basic Medical SciencesPeking UniversityBeijing100191China Baruch S.Blumberg Institute DoylestownPA18901USA Shenzhen Sanyuansheng Biotechnology Co. LtdShenzhen518000China Precision Medicine Center of Zhengzhou University Academy of Medical SciencesZhengzhou UniversityZhengzhou450001China Peking University-Sansure Biotech Joint Laboratory of Molecular Medicine Sansure Biotech Co.LtdChangsha410205China

Naturally occurred precore(PC,G1896A)and/or basal core promoter(BCP,A1762T/G1764A)mutations are prevalent in chronic HBV-infected patients,especially those under HBeAg-negative ***,the replicative capacity of HBV with PC/BCP mutations remains ***,meta-analysis showed that,only under HBeAg-negative status,the serum HBV DNA load in patients with PC mutation was 7.41-fold higher than those without the *** PC mutation alone and BCPþPC mutations promoted HBV replication in cell and hydrodynamic injection mouse *** human hepatocyte chimeric mouse model,BCPþPC mutations led to elevated replicative capacity and intrahepatic core protein ***,preC RNA harboring PC mutation could serve as mRNA to express core and P proteins,and such pgRNA-like function favored the maintenance of cccDNA pool under HBeAg-negative ***,BCPþPC mutations induced more extensive and severe human hepatocyte damage as well as activated endoplasmic reticulum stress and TNF signaling pathway in livers of chimeric *** study indicates that HBeAg-negative patients should be monitored on HBV mutations regularly and are expected to receive early antiviral treatment to prevent disease progression.

关键词： Hepatitis B virus Precore mutation Basal core promoter mutations Endoplasmic reticulum stress

Bending results of graphene origami reinforced doubly curved shell

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Defence Technology（防务技术） 2024年第5期35卷 198-210页

作者： Nan Yang Yunhe zou Mohammad Arefi School of Architecture and Civil Engineering Qiqihar UniversityQiqihar 161006HeilongjiangChina School of Mechanical Engineering Inner Mongolia University of TechnologyHohhot 010051Inner MongoliaChina Inner Mongolia Key Laboratory of Special Service Intelligent Robotics Hohhot 010051Inner MongoliaChina Faculty of Mechanical Engineering Department of Solid MechanicsUniversity of KashanKashan87317-51167Iran

The present work investigates higher order stress,strain and deformation analyses of a shear deformable doubly curved shell manufactures by a Copper(Cu)core reinforced with graphene origami auxetic metamaterial subjected to mechanical and thermal *** effective material properties of the graphene origami auxetic reinforced Cu matrix are developed using micromechanical models cooperate both material properties of graphene and Cu in terms of temperature,volume fraction and folding *** principle of virtual work is used to derive governing equations with accounting thermal *** numerical results are analytically obtained using Navier's technique to investigate impact of significant parameters such as thermal loading,graphene amount,folding degree and directional coordinate on the stress,strain and deformation responses of the *** graphene origami materials may be used in aerospace vehicles and structures and defence technology because of their low weight and high stiffness.A verification study is presented for approving the formulation,solution methodology and numerical results.

关键词： Graphene origami Copper matrix Doubly curved Shear deformable Auxetic metamaterial

Dynamic impact properties of deep sandstone under thermal-hydraulicmechanical coupling loads

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Journal of Mountain Science 2024年第6期21卷 2113-2129页

作者： CAO Chunhui DING Haonan zou Baoping School of Civil Engineering and Architecture Zhejiang University of Science and TechnologyHangzhou 310023China Zhejiang-Singapore Joint Laboratory for Urban Renewal and Future City Hangzhou 310023China

The deep rock mass within coal mines situated in a challenging environment are characterized by high ground stress,high geotemperature,high osmotic water pressure,and dynamic disturbances from mechanical *** investigate the impact of this complex mechanical environment on the dynamic characteristics of roof sandstone in self-formed roadways without coal pillars,standard specimens of deep sandstone from the 2611 upper tunnel working face of the Yongmei Company within the Henan Coal Chemical Industry Group in Henan,China were prepared,and an orthogonal test was *** a self-developed geotechnical dynamic impact mechanics test system,triaxial dynamic impact tests under thermal-hydraulicmechanical coupling conditions were conducted on deep *** results indicate that under high confining pressure,deep sandstone exhibits pronounced brittle failure at low temperatures,with peak strength gradually decreasing as temperature and osmotic water pressure ***,under low confining pressure and low temperature,the brittleness of deep sandstone weakens gradually,while ductility ***,sandstone demonstrates higher peak strength at low temperatures under high axial pressure conditions,lower peak strength at high temperatures,and greater strain under low axial pressure and high osmotic water *** in impact air pressure and osmotic water pressure have proportionally greater effects on peak stress and peak *** 50%of the input strain energy is utilized as effective energy driving the sandstone fracture *** analysis identifies the optimal combination of factors affecting the peak stress and peak strain of *** the coupling effect,intergranular and transgranular fractures occur within the *** images illustrate that the damage forms range from minor damage with multiple fissures to extensive fractures and severe *** study elucidates the varied dynamic impact me

关键词： Deep sandstone Thermal-hydraulicmechanical coupling Dynamic impact Stress-strain Failure Modes Polar analysis

Jackknife Model Averaging for Composite Quantile Regression

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Journal of Systems Science & Complexity 2024年第4期37卷 1604-1637页

作者： YOU Kang WANG Miaomiao zou Guohua School of Mathematical Sciences Capital Normal UniversityBeijing 100089China School of Chinese Materia Medica Beijing University of Chinese MedicineBeijing 100105China

In this paper,the authors propose a frequentist model averaging method for composite quantile regression with diverging number of *** from the traditional model averaging for quantile regression which considers only a single quantile,the proposed model averaging estimator is based on multiple *** well-known delete-one cross-validation or jackknife approach is applied to estimate the model *** resultant jackknife model averaging estimator is shown to be asymptotically optimal in terms of minimizing the out-of-sample composite final prediction *** studies are conducted to demonstrate the finite sample performance of the new model averaging *** proposed method is also applied to the analysis of the stock returns data and the wage data.

关键词： Asymptotic optimality composite quantile regression cross-validation model averaging

High-timing-precision detection of single X-ray photons by superconducting nanowires

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National Science Review 2024年第1期11卷 194-203页

作者： Shuya Guo Jingrou Tan Hengbin Zhang Jinguang Wang Tianhao Ji Labao Zhang Xiaolong Hu Jian Chen jun Xie Kai zou Yun Meng Xiaomin Bei ling-An Wu Qi Chen Hao Wang Xuecou Tu Xiaoqing Jia Qing-Yuan Zhao lin Kang Peiheng Wu Research Institute of Superconductor Electronics Nanjing University Qian Xuesen Laboratory of Space Technology Beijing National Laboratory of Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Hefei National Laboratory School of Precision Instrument and Optoelectronic Engineering Tianjin University Key Laboratory of Optoelectronic Information Science and Technology Ministry of Education

Precisely acquiring the timing information of individual X-ray photons is important in both fundamental research and practical applications. The timing precision of commonly used X-ray single-photon detectors remains in the range of one hundred picoseconds to microseconds. In this work, we report on high-timing-precision detection of single X-ray photons through the fast transition to the normal state from the superconductive state of superconducting nanowires. We successfully demonstrate a free-running X-ray single-photon detector with a timing resolution of 20.1 ps made of 100-nm-thick niobium nitride film with an active area of 50 μm by 50 μm. By using a repeated differential timing measurement on two adjacent X-ray single-photon detectors, we demonstrate a precision of 0.87 ps in the arrival-time difference of X-ray photon measurements. Therefore, our work significantly enhances the timing precision in X-ray photon counting, opening a new niche for ultrafast X-ray photonics and many associated applications.

关键词： single-photon detection timing precision superconductor ultrafast phenomenon pulsar X-ray navigation

Covariate-Assisted Matrix Completion with Multiple Structural Breaks

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Journal of Systems Science & Complexity 2024年第2期37卷 692-728页

作者： MENG Jing FENG Long zou Changliang WANG Zhaojun School of Statistics and Data Science KLMDASRLEBPSand LPMCNankai UniversityTianjin 300071China

In matrix completion,additional covariates often provide valuable information for completing the unobserved entries of a high-dimensional low-rank matrix *** this paper,the authors consider the matrix recovery problem when there are multiple structural breaks in the coefficient matrix β under the column-space-decomposition model A=Xβ+B.A cumulative sum(CUSUM)statistic is constructed based on the penalized estimation of β.Then the CUSUM is incorporated into the Wild Binary Segmentation(WBS)algorithm to consistently estimate the location of ***,a nearly-optimal recovery of A is *** findings are further corroborated via numerical experiments and a real-data application.

关键词： Additional covariates matrix completion multiple structural breaks wild Binary Segmentation

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Causal relationship between feelings and cognitive decline:An univariable and multivariable Mendelian randomization study

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World Journal of Psychiatry 2024年第3期14卷 421-433页

作者： Juan Liu lin Liu Yi-Xin Hu Jian-Hua Li Xiao zou Hao-Yun Zhang Li Fan Department of Cardiology The Second Medical Center&National Clinical Research Center for Geriatric DiseasesChinese PLA General HospitalBeijing 100853China Department of Pulmonary and Critical Care Medicine The Second Medical Center&National Clinical Research Center for Geriatric DiseasesChinese PLA General HospitalBeijing 100853China The Fourth Department of Geriatric Health Care The Second Medical Center&National Clinical Research Center for Geriatric DiseasesChinese PLA General HospitalBeijing 100853China Department of Anesthesiology First Medical Center of Chinese PLA General HospitalBeijing 100853China

BACKGROUND While the impact of depression on cognition is well-documented,the relationship between feelings and cognition has received limited *** To explore the potential association between feelings and cognition with a twosample Mendelian randomization(MR)*** Our analysis utilized genome-wide association data on various feelings(fed-up feelings,n=453071;worrier/anxious feelings,n=450765;guilty feelings,n=45-0704;nervous feelings,n=450700;sensitivity/hurt feelings,n=449419;miserableness,n=454982;loneliness/isolation,n=455364;happiness,n=152348)in the European population and their impact on cognitive functions(intelligence,n=269867).Conducting a univariable MR(UVMR)analysis to assess the relationship between feelings and *** this analysis,we applied the inverse variance weighting(IVW),weighted median,and MR Egger ***,we performed sensitivity analysis(leave-one-out analysis),assessed heterogeneity(using MR-PRESSO and Cochran’s Q test),and conducted multiple validity test(employing MR-Egger regression).Subsequently,a multivariable MR(MVMR)analysis was employed to examine the impact of feelings on *** served as the primary method in the multivariable analysis,complemented by median-based and MR-Egger *** In this study,UVMR indicated that sensitivity/hurt feelings may have a negative causal effect on cognition(OR=0.63,95%CI:0.43-0.92,P=0.017).After adjustment of other feelings using MVMR,a direct adverse causal effect on cognition was observed(OR_(MVMR)=0.39,95%CI:0.17-0.90,P_(MVMR)=0.027).While a potential increased risk of cognitive decline was observed for fed-up feelings in the UVMR analysis(ORUVMR=0.64,95%CI:0.42-0.97,PUVMR=0.037),this effect disappeared after adjusting for other feelings(OR_(MVMR)=1.42,95%CI:0.43-4.74,P_(MVMR)=0.569).These findings were generally consistent across MV-IVW,median-based,and MR-Egger ***-Egger regression revealed pleiotropy in the impact of worrier/anxious

关键词： Mendelian randomization analysis Feelings Cognition Intelligence

Brain Cognition Mechanism-Inspired Hierarchical Navigation Method for Mobile Robots

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Journal of Bionic Engineering 2024年第2期21卷 852-865页

作者： Qiang zou Chengdong Wu Ming Cong Dong Liu Faculty of Robot Science and Engineering Northeastern UniversityShenyang110819China School of Mechanical Engineering Dalian University of TechnologyDalian116024China

Autonomous navigation is a fundamental problem in *** methods generally build point cloud map or dense feature map in perceptual space;due to lack of cognition and memory formation mechanism,traditional methods exist poor robustness and low cognitive *** a new navigation technology that draws inspiration from mammal’s navigation,bionic navigation method can map perceptual information into cognitive space,and have strong autonomy and environment *** improve the robot’s autonomous navigation ability,this paper proposes a cognitive map-based hierarchical navigation ***,the mammals’navigation-related grid cells and head direction cells are modeled to provide the robots with location *** then a global path planning strategy based on cognitive map is proposed,which can anticipate one preferred global path to the target with high efficiency and short ***,a hierarchical motion controlling method is proposed,with which the target navigation can be divided into several sub-target navigation,and the mobile robot can reach to these sub-targets with high confidence ***,some experiments are implemented,the results show that the proposed path planning method can avoid passing through obstacles and obtain one preferred global path to the target with high efficiency,and the time cost does not increase extremely with the increase of experience nodes *** motion controlling results show that the mobile robot can arrive at the target successfully only depending on its self-motion information,which is an effective attempt and reflects strong bionic properties.

关键词： Bionic navigation Spatial localization cells Global path planning Hierarchical motion controlling

Vibration harmonic suppression technology for electromagnetic vibrators based on an improved sensorless feedback control method

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Frontiers of Information Technology & Electronic Engineering 2024年第3期25卷 472-483页

作者： Wei LI junning CUI Xingyuan BIAN Limin zou Centerof Ultra-precision Optoelectronic Instrument Engineering Harbin Institute of TechnoogyHarbin 0080China Key Lab of Ultra-precision Intlligent Instrumentation(Harbin Institute of Technology).Ministry of Industry and Information Technology Harbin 150080China

To realize low harmonic distortion of the vibration waveform output from electromagnetic vibrators,we propose a vibration harmonic suppression technology based on an improved sensorless feedback control *** changing the original driving circuit,the alternating current(AC)equivalent resistance of the driving coil is used to obtain high-precision vibration velocity information,and then a simple and reliable velocity feedback control system is *** the study of the effect of different values of key parameters on the system,we have achieved an effective expansion of the velocity characteristic frequency band of low-frequency vibration,resulting in an enhanced harmonic suppression capability of velocity feedback *** present extensive experiments to prove the effectiveness of the proposed method and make comparisons with conventional control *** the frequency range of 0.01-1.00 Hz,without using any sensors,the method proposed in this study can reduce the harmonic distortion of the vibration waveform by about 40%compared to open-loop control and by about 20%compared to a conventional sensorless feedback control method.

关键词： Vibration calibration Electromagnetic vibrators Harmonic suppression Sensorless control method Velocity feedback control