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Snowpack variations and their hazardous effects under climate warming in the central Tianshan Mountains

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Advances in Climate Change Research 2024年第3期15卷 442-451页

作者： Jian-Sheng HAO yan wang lan-Hai LI Key Laboratory of land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences(CAS)Beijing 100101China Xinjiang Key Laboratory of Water Cycle and Utilization in Arid Zone Urumqi 830011China State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Tianshan Snowcover and Avalanche Observation and Research Station of Xinjiang Xinyuan 835800China CAS Research Center for Ecology and Environment of Central Asia Urumqi 830011China

Climate change alters snowpack evolution,which in turn influences the likelihood of snow avalanches and flood *** lack of systemic observational data on key snow characteristics in high mountains remains a scientific challenge in terms of systematically elucidating the dynamic chain of variations in climate-snowpack-snow *** restricts our understanding and poses challenges in the prediction of snow-related disaster *** such,this study analysed the variations of temperature and snowfall and the physical characteristics of snowpacks based on ground-based observations from the Kunse River Valley situated in the Tianshan Mountains from 1967 to *** results reveal that the temperature increased significantly by 0.32°C per decade(plands,road transportation,water-electricity infrastructure and several other human ***,these insights are critical for providing vital information that can deepen our understanding of the impact of climate change on snowpack characteristics and improve management strategies for snow-related disaster prevention and mitigation.

关键词： Climate change Snowpack variations Snow-related disaster Tianshan Mountains

Application of Bionic Technology in Marine Cruise Equipment:Research Progress and Development Trends

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Journal of Bionic Engineering 2024年第3期21卷 1117-1155页

作者： Kunhui Luo lan yan Zhiyi Zhu Zhongqiu wang Hongru wang Feng Jiang School of Electromechanical and Automation Huaqiao UniversityXiamen36102China National Local Joint Engineering Research Center for Intelligent Manufacturing Technology of Brittle Material Products Xiamen361021China Institute of Oceanographic Instrumentation Shandong Academy of SciencesQilu University of Technology(Shandong Academy of Sciences)Qingdao266100China Shandong Provincial Key Laboratory of Marine Monitoring Instrument Equipment Technology Qingdao266100China National Engineering and Technological Research Center of Marine Monitoring Equipment Qingdao266100China Institute of Manufacturing Engineering Huaqiao UniversityXiamen361021China

This article provides an overview of the application of bionic technology in marine cruising equipment,discussing its research progress and future development *** cruising is a crucial means of gaining insights into the marine environment and conducting scientific ***,conventional marine cruising equipment faces numerous challenges when dealing with complex and ever-changing marine *** technology,as a means of drawing inspiration from the structure and functions of living organisms,offers new approaches and methods to address the challenges faced by marine cruising equipment and has found widespread *** article primarily focuses on the applications and historical developments of bionic technology in propulsion methods,drag reduction,and surface *** summarizes the design principles,manufacturing techniques,and optimization methods for marine biomimetic cruising ***,this paper analyzes the achievements,challenges,and future directions of bionic technology in marine cruising *** application of bionic technology in marine cruising equipment holds vast potential for development,enabling us to better confront the challenges of marine exploration and research by drawing wisdom from nature and driving advancements in marine science.

关键词： Marine cruising equipment Bionic technology Propulsion methods Drag reduction Surface antifouling

Wind disturbance compensated path-following control for fixed-wing UAVs in arbitrarily strong winds

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Chinese Journal of Aeronautics 2024年第2期37卷 431-445页

作者： Hao LU lan GAO Yunda yan Mingzhe HOU Chenliang wang Hangzhou Innovation Institute Beihang UniversityHangzhou 310051China School of Information Science and Technology Hangzhou Normal UniversityHangzhou 311121China Department of Computer Science University College LondonLondon WC1E 6BTUnited Kingdom Center for Control Theory and Guidance Technology Harbin Institute of TechnologyHarbin 150001China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

Wind is the primary challenge for low-speed fixed-wing unmanned aerial vehicles to follow a predefined flight *** cope with various wind conditions,this paper proposes a wind disturbance compensated path following control strategy where the wind disturbance estimate is incorporated with the nominal guiding vector field to provide the desired airspeed direction for the *** the control input vector for the outer-loop kinematic subsystem needs to satisfy a magnitude constraint,a scaling mechanism is introduced to tune the proportions of the compensation and nominal ***,an optimization problem is formulated to pursue a maximum wind compensation in strong winds,which can be solved analytically to yield two scaling factors.A cascaded inner-loop tracking controller is also designed to fulfill the outer-loop wind disturbance compensated guiding vector ***-fidelity simulation results under sensor noises and realistic winds demonstrate that the proposed path following algorithm is less sensitive to sensor noises,achieves promising accuracy in normal winds,and mitigates the deviation from a desired path in wild winds.

关键词： Path following Guiding vector field Wind disturbance Disturbance rejection Fixed wings

Thermal and ignition properties of hexanitrostilbene(HNS) microspheres prepared by droplet microfluidics

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Defence Technology（防务技术） 2023年第7期25卷 166-173页

作者： Rui-shan Han Fei-peng Lu Fang Zhang yan-lan wang Mi Zhou Guo-sheng Qin Jian-hua Chen Hai-fu wang En-yi Chu State Key Laboratory of Explosion and Technology Beijing Institute of TechnologyBeijing100081China Science and Technology on Applied Physical Chemistry Laboratory Shaanxi Applied Physics-Chemistry Research InstituteXi'an710061ShaanxiChina

HNS-IV(Hexanitrostilbene-IV) is the main charge of the exploding foil initiators(EFI), and the microstructure of the HNS will directly affect its density, flowability, sensitivity, and stability. HNS microspheres were prepared using droplet microfluidics, and the particle size, morphology, specific surface area, thermal performance, and ignition threshold of the HNS microspheres were characterized and tested. The results shown that the prepared HNS microspheres have high sphericity, with an average particle size of 20.52 μm(coefficient of variation less than 0.2), and a specific surface area of 21.62 m^(2)/g(6.87 m^(2)/g higher than the raw material). Without changing the crystal structure and thermal stability of HNS-IV, this method significantly enhances the sensitivity of HNS-IV to short pulses and reduces the ignition threshold of the slapper detonator to below 1000 V. This will contribute to the miniaturization and low cost of EFI.

关键词： Microfluidics HNS microspheres Thermal stability Ignition threshold

Mechanism of over-activation in direct pathway mediated by dopamine D_1 receptor in rats with levodopa-induced dyskinesias

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Neuroscience Bulletin 2006年第3期22卷 159-164页

作者： Xue-Bing CAO Qiang GUAN yan XU lan wang Sheng-Gang SUN Department of Neurology Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430022 China

Objective To study the changes of prodynorphin （PDyn） gene expression and dopamine and cAMPregulated phosphoprotein of 32 kDa （DARPP-32） phosphorylation in rats with levodopa-induced dyskinesias （LID）, and to explore the mechanism of over-activation in direct pathway mediated by dopamine D1 receptor. Methods Parkinson＇s disease （PD） rats were received levodopa （10 mg/kg, i.p.） for 28 d to get the LID rats. According to the behavior scale, LID rats were divided into mild （n=8） and severe （n=16） groups. On day 29, 8 rats in severe LID group were given an acute intraperitoneal injection of MK-801 （0.1 mg/kg） 15 min before levodopa treatment （MK-801 group, n=8）. The normal rats received same course and dosage of levodopa as the control group （n=8）. Hybridization in situ was used to measure the expression of PDyn mRNA in striatum. Protein and mRNA levels of total DARPP-32 and phospho-Thr-34 DARPP-32 level were measured by immunoblotting and RT-PCR, respectively. Results The levels of PDyn mRNA and phospho-Thr-34 DARPP-32 increased significantly in LID rats compared with control rats （P〈0.01）, and they also increased markedly in severe LID group compared with mild group （P〈0.01）. Conclusion Phospho-Thr-34 DARPP-32 level was increased in LID rats, which contributed to the over-activation of direct pathway mediated by dopamine D1 receptor.

关键词： levodopa-induced dyskinesias Prodynorphin Dopamine and cAMP-regulated phosphoprotein of 32 kDa

Shape Memory Polymer Composites:4D Printing,Smart Structures,and Applications

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Research 2024年第3期2023卷 319-343页

作者： Shiyu yan Fenghua Zhang lan Luo Linlin wang yanju Liu Jinsong Leng Centre for Composite Materials and Structures Harbin Institute of Technology(HIT)No.2 Yikuang StreetHarbin 150000People's Republic of China Department of Astronautic Science and Mechanics Harbin Institute of Technology(HIT)No.92 West Dazhi StreetHarbin 150000People's Republic of China.

Shape memory polymers (SMPs) and their composites (SMPCs) are smart materials that can be stably deformed and then return to their original shape under external stimulation, thus having a memory of their shape. Three-dimensional (3D) printing is an advanced technology for fabricating products using a digital software tool. Four-dimensional (4D) printing is a new generation of additive manufacturing technology that combines shape memory materials and 3D printing technology. Currently, 4D-printed SMPs and SMPCs are gaining considerable research attention and are finding use in various fields, including biomedical science. This review introduces SMPs, SMPCs, and 4D printing technologies, highlighting several special 4D-printed structures. It summarizes the recent research progress of 4D-printed SMPs and SMPCs in various fields, with particular emphasis on biomedical applications. Additionally, it presents an overview of the challenges and development prospects of 4D-printed SMPs and SMPCs and provides a preliminary discussion and useful reference for the research and application of 4D-printed SMPs and SMPCs.

关键词： composites printing Smart

Tunable Phase Structure of Side-chain Liquid Crystalline Polymers Enabled by Molecular Engineering of Dual Mesogenic Cores

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Chinese Journal of Polymer Science 2024年第10期42卷 1459-1469,I0009页

作者： Wen-Huan Yao lan-Sheng Liu Jie Zhao yan-Xia wang An-Zhi Ma Zheng-Rui Ma lan-Ying Zhang Ruo-Chen lan College of Chemistry and Chemical Engineering Hunan UniversityChangsha410082China Key Laboratory of Eco-Functional Polymer Materials of the Ministry of Education Key Laboratory of Eco-Environmental Polymer Materials of Gansu ProvinceCollege of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhou730070China Department of Materials Science and Engineering College of EngineeringPeking UniversityBeijing100871China Institute of Advanced Materials&Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education College of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchang330022China

A series of novel side-chain liquid crystalline(SCLC)copolymers were synthesized by attaching two distinct mesogenic units,namely a chiral cholesteryl-based monomer(M1)and an achiral biphenyl-based monomer(M2),to a poly(3-mercaptopropylmethylsiloxane)(PMMS)backbone via thiol-ene click *** influence of side chain composition on the self-assembly behavior and phase structures of these SCLC copolymers was systematically investigated using different *** indicate that three distinct liquid crystalline phases and four unique molecular configurations were identified within the polymer series,with the emergence of the liquid crystalline phase being a synergistic outcome of the two distinct side *** study underscores the critical influence of side chain dimensions,rigidity,and spatial volume on the self-assembly structures and phase characteristics of liquid crystalline polymers,providing valuable insights for the rational design and development of advanced functional materials with tailored properties.

关键词： Liquid crystalline copolymers Self-assembly Phase structure Chiral molar ratio

Transient elastography with controlled attenuation parameter for the diagnosis of colorectal polyps in patients with nonalcoholic fatty liver disease

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World Journal of Clinical Cases 2024年第12期12卷 2050-2055页

作者： lan wang yan-Fei Li Li-Feng Dong Department of Gastroenterology Beijing Chuiyangliu HospitalBeijing 100022China

BACKGROUND The severity of nonalcoholic fatty liver disease(NAFLD)and lipid metabolism are related to the occurrence of colorectal ***-controlled attenuation parameters(liver-CAPs)have been established to predict the prognosis of hepatic steatosis *** To explore the risk factors associated with colorectal polyps in patients with NAFLD by analyzing liver-CAPs and establishing a diagnostic *** Patients who were diagnosed with colorectal polyps in the Department of Gastroenterology of our hospital between June 2021 and April 2022 composed the case group,and those with no important abnormalities composed the control *** area under the receiver operating characteristic curve was used to predict the diagnostic *** were considered statistically significant when P0.05).When the liver-CAP was greater than 291 dB/m,colorectal polyps were more likely to *** The levels of TG and liver-CAP in patients with colorectal polyps are significantly greater than those patients without ***-CAP alone can be used to diagnose NAFLD with colorectal polyps.

关键词： Colorectal polyps Nonalcoholic fatty liver disease Liver-controlled attenuation parameter Liver fibroscan Diagnostic model

Placenta-derived mesenchymal stem cells attenuate secondary brain injury after controlled cortical impact in rats by inhibiting matrix metalloproteinases

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BIOCELL 2024年第1期48卷 149-162页

作者： PING yanG YUANXIANG lan ZHONG ZENG yan wang HECHUN XIA Department of Neurosurgery School of Clinical MedicineNingxia Medical UniversityYinchuanChina Key Laboratory of Ningxia Stem Cell and Regenerative Medicine General Hospital of Ningxia Medical UniversityYinchuanChina Department of Neurosurgery Xi’an International Medical Center HospitalXi’anChina

Background:As a form of biological therapy,placenta-derived mesenchymal stem cells(PDMSCs)exhibit considerable promise in addressing the complex pathological processes of traumaticbrain injury(TBI)due to their multi-target and multi-pathway mode of ***&Methods:This study investigates the protective mechanisms and benefits of PDMSCs in mitigating the effects of controlled cortical impact(CCI)in rats and glutamate-induced oxidative stress injury in HT22 cells in *** primary objective is to provide evidence supporting the clinical application of ***:In the in vivo arm of our investigation,we observed a swift elevation of matrix metalloproteinase-9(MMP-9)in the proximal cortex of injured brain tissues after ***,distinguished by their heightened expression of metalloproteinase tissue inhibitors-1 and-2(TIMP-1 and TIMP-2):were intravenously administered via the caudal *** intervention yielded significant reductions in the permeability of the blood-brain barrier(BBB):the extent of brain edema,the levels of inflammatory cytokines IL-1βand TNF-αin damaged brain tissue,and the activation status of microglia in CCI-afflicted *** the realm of in vitro experiments,PDMSC-conditioned media demonstrated substantial reductions in mortality rates and cleaved caspase-3 levels in glutamate-induced HT22 cells compared with conventional ***,this advantage was negated upon the introduction of neutralizing antibodies targeting TIMP-1 and ***:Collectively,our findings underscore the potential of PDMSCs in alleviating oxidative stress injury and secondary brain injury in the pathological process of TBI.

关键词： Traumatic brain injury Mesenchymal stem cells Oxidative stress Matrix metalloproteinases