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Genetic and biological properties of H9N2 avian influenza viruses isolated in central China from2020 to 2022

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Journal of Integrative Agriculture 2024年第8期23卷 2778-2791页

作者： Libin Liang Yaning bai Wenyan Huang Pengfei Ren xing Li Dou Wang Yuhan Yang Zhen Gao Jiao Tang xingchen Wu Shimin Gao Yanna Guo Mingming Hu Zhiwei Wang Zhongbing Wang Haili Ma Junping Li College of Veterinary Medicine Shanxi Agricultural UniversityJinzhong 030801China Shanxi Provincial Animal Disease Prevention and Control Center Taiyuan 030000China

The H9N2 subtype of avian influenza virus(AIV)is widely prevalent in poultry and wild birds globally,and has become the predominant subtype circulating in poultry in *** H9N2 AIV can directly or indirectly(by serving as a"donor virus")infect humans,posing a significant threat to public ***,there is a lack of in-depth research on the prevalence of H9N2 viruses in Shanxi Province,central *** this study,we isolated 14 H9N2 AIVs from October 2020 to April 2022 in Shanxi Province,and genetic analysis revealed that these viruses belonged to 7 different *** study on animals revealed that the H9N2 strains we identified displayed high transmission efficiency among chicken populations,and exhibited diverse replication abilities within these *** viruses could replicate efficiently in the lungs of mice,with one strain also demonstrating the capacity to reproduce in organs like the brain and *** the cellular level,the replication ability of different H9N2 strains was evaluated using plaque formation assays and multi-step growth curve assays,revealing significant differences in the replication and proliferation efficiency of the various H9N2 viruses at the cellular *** antigenicity analysis suggested that these isolates could be classified into 2 separate antigenic *** research provides crucial data to help understand the prevalence and biological characteristics of H9N2 AIVs in central *** also highlights the necessity of enhancing the surveillance of H9N2 AIVs.

关键词： avian influenza virus H9N2 central China pathogenicity antigenicity

Palladium-catalyzed multi components oxy-aminofluorination and aminofluorination of gem-difluoroalkenes

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Chinese Chemical Letters 2024年第2期35卷 420-425页

作者： Fen Wu Xin Li Junbiao Chang Dachang bai State Key Laboratory of Antiviral Drugs NMPA Key Laboratory for Research and Evaluation of Innovative DrugKey Laboratory of Green Chemical Media and ReactionsMinistry of EducationSchool of Chemistry and Chemical EngineeringPingyuan LaboratoryHenan Normal UniversityXinxiang 453007China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

Organofluorine compounds are widely used in the realm of drug discovery and material ***,we developed palladium catalyzed intermolecular aminofluorination and oxy-aminofluorination of gem‑difluoroalkenes with N-fluorobenzenesulfonimide(NFSI),in which NFSI was used as the nitrogen source and *** reaction provides an efficient and straightforward synthesis route of a series ofα-trifluoromethyl benzylic ***,three/four components oxy-aminofluorination processes were realized to giveα-trifluoromethyl benzylic ether with a terminal amino group,which proceed through C(sp^(3))-O bond cleavage of easily available ether and simultaneous introduced a fluorine,an amino and an oxy substituent in one pot with excellent *** divergent reactivity not only included the incorporation of one ether molecular,but also much more challenged two ether insertion with excellent selectivity through succession C(sp^(3))-O bonds *** protocol allows for concise synthesis of high value amines with fluoroalkyl-substituents and selectively transformation of easily available ethers by high-valent palladium catalysis.

关键词： Palladium Multi components Aminofluorination Oxy-aminofluorination C(sp^(3))-O bond cleavage

Prospects of the Multi-channel Photometric Survey Telescope in the Cosmological Application of Type Ia Supernovae

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Research in Astronomy and Astrophysics 2024年第4期24卷 183-191页

作者： Zhenyu Wang Jujia Zhang Xinzhong Er Jinming bai Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China International Centre of Supernovae Yunnan Key LaboratoryKunming 650216China South-Western Institute for Astronomy Research Yunnan UniversityKunming 650500China

The Multi-channel Photometric Survey Telescope(Mephisto)is a real-time,three-color photometric system designed to capture the color evolution of stars and transients *** telescope system can be crucial in cosmological distance measurements of low-redshift(low-z,z■0.1)Type Ia supernovae(SNe Ia).To optimize the capabilities of this instrument,we perform a comprehensive simulation study before its official operation is scheduled to *** considering the impact of atmospheric extinction,weather conditions,and the lunar phase at the observing site involving the instrumental features,we simulate light curves of SNe Ia obtained by *** best strategy in the case of SN Ia cosmology is to take the image at an exposure time of 130 s with a cadence of 3 *** this condition,Mephisto can obtain hundreds of high-quality SNe Ia to achieve a distance measurement better than 4.5%.Given the on-time spectral classification and monitoring of the Lijiang 2.4 m Telescope at the same observatory,Mephisto,in the whole operation,can significantly enrich the well-calibrated sample of supernovae at low-z and improve the calibration accuracy of high-z SNe Ia.

关键词： (stars:)supernovae:general (cosmology:)cosmological parameters telescopes

Contactin-associated protein-like 2(CNTNAP2)mutations impair the essentialα-secretase cleavages,leading to autism-like phenotypes

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1625-1636页

作者： Qing Zhang Mengen xing Zhengkai Bao Lu Xu Yang bai Wanqi Chen Wenhao Pan Fang Cai Qunxian Wang Shipeng Guo Jing Zhang Zhe Wang Yili Wu Yun Zhang Jia-Da Li Weihong Song Oujiang Laboratory(Zhejiang Lab for Regenerative Medicine Vision and Brain Health)Zhejiang Key Laboratory of Alzheimer's DiseaseZhejiang Provincial Clinical Research Center for Mental DisordersSchool of Mental Health and Wenzhou Kangning HospitalThe Second Affiliated Hospital and Yuying Children's HospitalInstitute of AgingWenzhou Medical UniversityWenzhouZhejiang 325035China Townsend Family Laboratories Department of PsychiatryBrain Research CenterThe University of British Columbia2255 Wesbrook MallVancouverBC V6T 1Z3Canada Chongqing Key Laboratory of Translational Medical Research in Cognitive Development and Learning and Memory Disorders Ministry of Education Key Laboratory of Child Development and DisordersChildren's Hospital of Chongqing Medical UniversityChongqing 400014China Center for Medical Genetics Hunan Key Laboratory of Animal Models for Human DiseasesHunan Key Laboratory of Medical GeneticsHunan International Scientific and Technological Cooperation Base of Animal Models for Human DiseasesSchool of Life SciencesCentral South UniversityChangsha 410078 HunanChina The National Clinical Research Center for Geriatric Disease Xuanwu HospitalCapital Medical UniversityBeijing 100053Chin

Mutations in the Contactin-associated protein-like 2(CNTNAP2)gene are associated with autism spectrum disorder(ASD),and ectodomain shedding of the CNTNAP2 protein plays a role in its ***,key enzymes involved in the C-terminal cleavage of CNTNAP2 remain largely unknown,and the effect of ASD-associated mutations on this process and its role in ASD pathogenesis remain *** this report we showed that CNTNAP2 undergoes sequential cleavages by furin,ADAM10/17-dependent a-secretase and presenilindependent *** identified that the cleavage sites of ADAM10 and ADAM17 in CNTNAP2 locate at its C-terminal residue I79 and L96,and the main a-cleavage product C79 by ADAM10 is required for the subsequent y-secretase cleavage to generate CNTNAP2 intracellular domain(CICD).ASD-associated CNTNAP2 mutations impair the a-cleavage to generate C79,and the inhibition leads to ASDIlike repetitive and social behavior abnormalties in the Cntnap2l1254T knock-in ***,exogenous expression of 79 improves autism-ike phenotypes in the Cntnap2^(11254T) knock-in and Cntnap2^(-/-)knockout *** data demonstrates that the a-secretase is essential for CNTNAP2 processing and its *** study indicates that inhibition of the cleavage by pathogenic mutations underlies ASD pathogenesis,and upregulation of its C-terminal fragments could have therapeutical potentials for ASD treatment.

关键词： NAP2 cleavage subsequent

Infrared radiation characteristics of dagger-type hypersonic missile

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Chinese Journal of Aeronautics 2024年第4期37卷 137-150页

作者： Xubo DU Qingzhen YANG Haoqi YANG Jin bai Yongqiang SHI School of Power and Energy Northwestern Polytechnical UniversityXi’an 710129China

Hypersonic vehicles emit strong infrared radiation from their high-temperature exhaust plume and body, which is critical for infrared early warning, tracking, and guidance. In this work, a comprehensive analysis is conducted on the factors involved in air dissociation reaction within the shock layer of hypersonic missile heads, as well as the multi-component afterburning effect of the exhaust plume. A novel Reverse Monte Carlo Method(RMCM) is proposed for infrared radiation calculation, which utilizes two-dimensional Low-Discrepancy Sequences(LDS) to improve computational accuracy. The numerical calculations for a dagger-type missile show that afterburning reactions increase the temperature on the centerline of the outlet exhaust plume by about 1000 K. The total infrared radiation intensity of the missile is the highest in the 1–3 μm band, with the hightemperature wall of the nozzle being the primary source of solid radiation, and gas radiation primarily coming from H_(2)O. The radiation intensity of the missile exhaust plume in the 3–5 μm band is the highest, with radiation sources primarily coming from CO_(2), CO, and HCl. Afterburning reactions of the exhaust plume increase the total infrared radiation intensity of the missile by about 0.7times. These results can provide reference for the detection and guidance of hypersonic missiles.

关键词： Hypersonic vehicles Infrared radiation Monte Carlo methods Low-discrepancy sequences Exhaust plume Afterburning

On extended state Kalman filter-based identification algorithm for aerodynamic parameters

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Control Theory and Technology 2024年第2期22卷 235-243页

作者： Wenyan bai Ruizhe Jia Peng Yu Wenchao Xue Beijing Aerospace Automatic Control Institute Beijing100854China School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing100083China Key Laboratory of Knowledge Automation for Industrial Processes Ministry of EducationBeijing100083China Key Laboratory of Systems and Control Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing100190China

In this paper, the problem of time-varying aerodynamic parameters identification under measurement noises is studied. By analyzing the key aerodynamic parameters that affect the aircraft control system, a system model with extended states for identifying equivalent aerodynamic parameters is established, and error parameters are extended to the system state, avoiding the difficulty caused by the unknown dynamic in the system. Furthermore, an identification algorithm based on extended state Kalman filter is designed, and it is proved that the algorithm has quasi-consistency, thus, the estimation error can be evaluated in real time. Finally, the simulation results under typical flight scenarios show that the designed algorithm can accurately identify aerodynamic parameters, and has desired convergence speed and convergence precision.

关键词： Aerodynamic parameters Parameter identification Extended state Kalman filter

Machining dynamics and chatters in micro-milling:A critical review on the state-of-the-art and future perspectives

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Chinese Journal of Aeronautics 2024年第7期37卷 59-80页

作者： Qingshun bai Peng WANG Kai CHENG Liang ZHAO Yabo ZHANG School of Mechanical and Electrical Engineering Harbin Institute of TechnologyHarbin 150001China Department of Mechanical and Aerospace Engineering Brunel University LondonUxbridge UB83PHUK

Micro-milling technology is widely applied in micro manufacturing,particularly for the fabrication of miniature and micro ***,the chatters and machining dynamics related issues in micro-milling are often the main challenges restricting its machining quality and *** research works have rendered that the machining dynamics and chatters in micro-milling are more complex compared with the conventional macro-milling process,likely because of the size effect and rigidity of the micro-milling system including the tooling,workpiece,process variables,materials involved,and the high-speed milling machines,and further their collective dynamic ***,in this paper,the state of the art focusing on micro-milling chatters and dynamics related issues over the past years are comprehensively and critically reviewed to provide some insights for potential researchers and ***,typical applications and the problems caused by the machining dynamics and chatters in micro-milling have been put forward in this ***,the research on the underlying micro-cutting mechanics and dynamics,stability analysis,chatters detection,and chatter suppression are summarized ***,the underlying scientific and technological challenges are discussed particularly against typical precision engineering ***,the possible future directions and trends in research and development of micro-milling have been discussed.

关键词： Micro-milling Machining dynamics Micro-cutting mechanics Stability lobe diagram(SLD) Chatters suppression Digital twin

Efficient synthesis of forsterite via high-temperature thermochemical reactions from boron mud waste without briquetting

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Particuology 2024年第4期87卷 124-132页

作者： Fangling Hu Liangliang Fu Qingjin Zhang Guangwen Xu Dingrong bai Key Laboratory on Resources Chermticals and Material of Ministry of Education Sheryang Unfversity of Chemical Technology.Shenyang110142China School of Chemical Engineering University of Science and Technology Liaoning.Anshan 114051China School of Materials Science and Engineering Shenyang University of Technology.Shenyang110142China

Forsterite is a highly demanded material in high-temperature industries due to its superior performance in elevated *** study proposes synthesizing high-quality forsterite via high-temperature thermochemical reactions using abundant boron mud *** new synthesis method capitalizes on the high reactivity of fine raw powder materials,enabling the reaction to reach completion at low temperatures *** chemical characteristics,microscopic morphology,and structure of synthe-sized samples are systematically studied using XRD and *** results confirm that boron mud can be efficiently transformed into forsterite after 10 min of reactions at 1500℃.The synthesized products attain over 98.7%densification and contain more than 85.0%forsterite with well-developed *** activation energy of forsterite grain growth in the 1100-1500℃temperature range is 165.5 kJ/*** study provides a low-cost method for producing forsterite and an efficient and environmentally friendly solution for treating solid waste.

关键词： Fluidized bed Boron mud Forsterite Solid state reaction Activation energy Grain growth

Effect of Direct Aging on Corrosion Behavior of AlSi10Mg Alloy Fabricated by Laser Powder Bed Fusion

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 266-282页

作者： Zhen Zhang Zhanyong Zhao Xiaofeng Li Beibei Wang Peikang bai Shanxi Key Laboratory of Controlled Metal Solidification and Precision Manufacturing School of Materials Science and EngineeringNorth University of ChinaTaiyuan030051China Technical Center Taiyuan Iron and Steel(Group)Co.LtdTaiyuan030003China School of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan030024China

Effect of direct aging of 170℃on corrosion behavior of laser powder bed fused AlSi10Mg(LPBF-AlSi10Mg)was studied by microstructure analysis,electrochemical analysis and X-ray photoelectron *** results show that direct aging of 170℃has little effect on melt pool and Si cellular structure,but promotes the precipitation of nano-Si particles and releases the residual *** increasing aging time from 0 to 4 h to 24 h,the corrosion property of the LPBF-AlSi10Mg is deteriorated,which is evidenced by increased corrosion current density and decreased pitting potential and polarization *** increasing the aging time,the thickness of the oxide film formed on surface of the LPBF-AlSi10Mg *** Si content of the oxide film of the sample aging for 4 h is the lowest,9.42 at.%,and it is the highest,18.62 at.%,for the sample aging for 24 *** electrochemical noise analysis reveals that the middle-frequency contribution of the Hilbert spectrum is responsible for the deteriorated corrosion performance,which corresponds to metastable pitting initiated by nano-Si particles.

关键词： Laser powder bed fusion AlSi10Mg Direct aging Corrosion