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Relationship of Retinal Nerve Fiber Layer Thickness and Retinal Vessel Calibers with Cognitive Impairment in the Asymptomatic Polyvascular Abnormalities Population

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Biomedical and Environmental Sciences 2024年第2期37卷 196-203页

作者： WANG Dan Dan WANG An Xin ZHANG Xiao Li WEI Wen Bin WU Shou Ling zhao Xing quan Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijing 100070China China National Clinical Research Center for Neurological Diseases Beijing 100070China Beijing Tongren Eye Center Beijing Key Laboratory of Ophthalmology and Visual ScienceBeijing Tongren HospitalCapital Medical UniversityBeijing 100005China Department of Cardiology Kailuan HospitalTangshan 063001HebeiChina

Objective Cognitive impairment(CI)in older individuals has a high morbidity rate worldwide,with poor diagnostic methods and susceptible population *** study aimed to investigate the relationship between different retinal metrics and CI in a particular population,emphasizing polyvascular *** We collected information from the Asymptomatic Polyvascular Abnormalities Community Study on retinal vessel calibers,retinal nerve fiber layer(RNFL)thickness,and cognitive function of 3,785participants,aged 40 years or *** regression was used to analyze the relationship between retinal metrics and cognitive *** stratified by different vascular statuses were also *** RNFL thickness was significantly thinner in the CI group(odds ratio:0.973,95%confidence interval:0.953–0.994).In the subgroup analysis,the difference still existed in the non-intracranial arterial stenosis,non-extracranial carotid arterial stenosis,and peripheral arterial disease subgroups(P<0.05).Conclusion A thin RNFL is associated with CI,especially in people with non-large vessel *** underlying small vessel change in RNFL and CI should be investigated in the future.

关键词： Retinal nerve fiber layer Cognitive impairment Polyvascular abnormality

Flow characteristics and hot workability of a typical low-alloy high-strength steel during multi-pass deformation

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 323-336页

作者： Mingjie zhao Lihong Jiang Changmin Li Liang Huang Chaoyuan Sun Jianjun Li Zhenghua guo School of Aeronautical Manufacturing Engineering Nanchang Hangkong UniversityNanchang 330063China Jiangxi Key Laboratory of Forming and Joining Technology for Aerospace Components Nanchang Hangkong UniversityNanchang 330063China State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China China National Erzhong Group Deyang Wanhang Die Forging Co.LTD. Deyang 618000China Hubei Huangshi Mold Industrial Technology Research Institute Huangshi 435007China

Heavy components of low-alloy high-strength(LAHS) steels are generally formed by multi-pass forging. It is necessary to explore the flow characteristics and hot workability of LAHS steels during the multi-pass forging process, which is beneficial to the formulation of actual processing parameters. In the study, the multi-pass hot compression experiments of a typical LAHS steel are carried out at a wide range of deformation temperatures and strain rates. It is found that the work hardening rate of the experimental material depends on deformation parameters and deformation passes, which is ascribed to the impacts of static and dynamic softening behaviors. A new model is established to describe the flow characteristics at various deformation passes. Compared to the classical Arrhenius model and modified Zerilli and Armstrong model, the newly proposed model shows higher prediction accuracy with a confidence level of 0.98565. Furthermore, the connection between power dissipation efficiency(PDE) and deformation parameters is revealed by analyzing the microstructures. The PDE cannot be utilized to reflect the efficiency of energy dissipation for microstructure evolution during the entire deformation process, but only to assess the efficiency of energy dissipation for microstructure evolution in a specific deformation parameter *** a result, an integrated processing map is proposed to better study the hot workability of the LAHS steel, which considers the effects of instability factor(IF), PDE, and distribution and size of grains. The optimized processing parameters for the multi-pass deformation process are the deformation parameters of 1223–1318 K and 0.01–0.08 s^(-1). Complete dynamic recrystallization occurs within the optimized processing parameters with an average grain size of 18.36–42.3 μm. This study will guide the optimization of the forging process of heavy components.

关键词： low-alloy high-strength steel work hardening rate constitutive model hot workability multi-pass deformation

Mechanical properties and thermal deformation behavior of low-cost titanium matrix composites prepared by a structure-optimized Y_(2)O_(3) crucible

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Journal of Iron and Steel Research International 2024年第3期31卷 738-751页

作者： Qian Dang Gang Huang Ye Wang Chi Zhang guo-huai Liu zhao-dong Wang The State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina School of Materials Science and Chemical Engineering Harbin University of Science and TechnologyHarbin 150004HeilongjiangChina School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870LiaoningChina

A porous yttrium oxide crucible with both thermal shock resistance and erosion resistance was developed by structural *** structure-optimized yttrium oxide crucible was proved to be suitable for melting highly reactive titanium ***-cost(TiB+Y2O_(3))-reinforced titanium matrix composites were prepared by vacuum induction melting using the prepared *** thermal deformation behavior and microstructure evolution of(TiB+Y2O_(3))-reinforced tita-nium matrix composites were investigated at deformation temperatures of 900-1100℃with strain rates of 0.001-1 *** results showed that the prepared yttrium oxide crucible had both thermal shock and erosion resistance,the low-cost titanium matrix composites could be prepared by the developed yttrium oxide crucibles which were homogeneous in composition and highly sensitive to strain rate and deformation temperature,and the peak and theological stresses decreased with increasing deformation temperature or decreasing strain *** addition,the average thermal deformation activation energy of the composites was calculated to be 574.6 kJ/mol by establishing the Arrhenius constitutive equation in consideration of the strain variables,and the fitting goodness between the predicted stress value and the measured value was 97.624%.The calculated analysis of the hot processing map showed that the best stable thermal deformation zone was located in the deformation temperature range of 1000-1100℃and strain rate range of 0.001-0.01 s^(-1),where the peak dissipation coefficient wasη=71%.In this zone,the deformation of the reinforcement and matrix was harmonious,the reinforcement was less likely to fracture,dynamic recrystallization occurred more fully and the alloy exhibited near steady rheological characteristics.

关键词： Yttrium oxide crucible Titanium matrix composite Thermal deformation behavior Constitutive equation Hot processing map Microstructure evolution

MADRL-based UAV swarm non-cooperative game under incomplete information

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Chinese Journal of Aeronautics 2024年第6期37卷 293-306页

作者： Ershen WANG Fan LIU Chen HONG Jing guo Lin zhao Jian XUE Ning HE School of Electronic and Information Engineering Shenyang Aerospace UniversityShenyang 110136China College of Robotics Beijing Union UniversityBeijing 100101China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China College of Smart City Beijing Union UniversityBeijing 100101China

Unmanned Aerial Vehicles(UAVs)play increasing important role in modern *** this paper,considering the incomplete observation information of individual UAV in complex combat environment,we put forward an UAV swarm non-cooperative game model based on Multi-Agent Deep Reinforcement Learning(MADRL),where the state space and action space are constructed to adapt the real features of UAV swarm air-to-air *** multi-agent particle environment is employed to generate an UAV combat scene with continuous observation *** recently popular MADRL methods are compared extensively in the UAV swarm noncooperative game model,the results indicate that the performance of Multi-Agent Soft Actor-Critic(MASAC)is better than that of other MADRL methods by a large *** swarm employing MASAC can learn more effective policies,and obtain much higher hit rate and win *** under different swarm sizes and UAV physical parameters are also performed,which implies that MASAC owns a well generalization ***,the practicability and convergence of MASAC are addressed by investigating the loss value of Q-value networks with respect to individual UAV,the results demonstrate that MASAC is of good practicability and the Nash equilibrium of the UAV swarm non-cooperative game under incomplete information can be reached.

关键词： UAV swarm Reinforcement learning Deep learning Multi-agent Non-cooperative game Nash equilibrium

Ultra-high specific surface area activated carbon from Taihu cyanobacteria via KOH activation for enhanced methylene blue adsorption

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Chinese Journal of Chemical Engineering 2024年第3期67卷 106-116页

作者： Yifang Mi Wenqiang Wang Sen Zhang Yalong guo Yufeng zhao guojin Sun Zhihai Cao Key Laboratory of Advanced Textile Materials and Manufacturing Technology and Engineering Research Center for Eco-Dyeing&Finishing of Textiles Ministry of EducationZhejiang Provincial Engineering Research Center for Green and Low-carbon Dyeing&FinishingZhejiang Sci-Tech UniversityHangzhou 310018China Key Laboratory for Technology in Rural Water Management of Zhejiang Province Zhejiang University of Water Resources and Electric PowerHangzhou 310018China

Cyanobacteria-based activated carbon(CBAC)was successfully prepared by pyrolysis-activation of Taihu *** the impregnation ratio and activated temperature were 2 and 800-C,respectively,the optimal CBACs possessed an ultra-high specific surface(2178.90 m^(2)·g^(-1))and plenty of micro-and meso-pores,as well as a high pore volume(1.01 cm^(3)·g^(-1)).Ascribed to ultra-high surface area,π-π interaction,electrostatic interaction,as well as hydrogen-bonding interactions,the CBACs displayed huge superiority in efficient dye *** saturated methylene blue adsorption capacity by CBACs could be as high as 1143.4 mg·g^(-1),superior to that of other reported biomass-activated *** adsorption was endothermic and modeled well by the pseudo-second-order kinetic,intra-particle diffusion,and Langmuir *** work presented the effectiveness of Taihu cyanobacteria adsorbent ascribed to its super large specific surface area and high adsorption ability.

关键词： Activated carbon Biomass Dye adsorption Taihu cyanobacteria

Controlling solid form and crystal habit of triphenylmethanol by antisolvent crystallization in a microfluidic device

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Chinese Chemical Letters 2024年第4期35卷 393-398页

作者： Jun Lu Jinrui Yan Yaohao guo Junjie Qiu Shuangliang zhao Bo Bao East China University of Science and Technology Shanghai 200237China Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology and School of Chemistry and Chemical Engineering Guangxi UniversityNanning 530004China

Crystal habit and crystal form are critical elements in determining product properties and functions. In this work, we developed a microfluidic antisolvent crystallization technique to rapidly screen and accurately control the solid form and crystal habit of triphenylmethanol(Ph_(3)COH). This advanced technique separates the primary mixing of solutions from crystal formation(nucleation and growth) by introducing the microfluidic device, avoiding clogging in microchannels to obtain high-quality crystals. The results show that we can achieve controllable preparation of pure 2Ph_(3)COH·DMSO(DMSO solvate), pure Ph_(3)COH(form β), and mixed crystals with different mass ratios. Moreover, the microscale can prompt the DMSO solvate to grow into hexagonal sheet-like and bulk crystals. We can regulate the aspect ratio of hexagonal sheet-like crystals in binary solvents and control the crystal habit of the form β to transition between long needle-like shapes and short hexagonal prisms in DMF-H_(2)O. Meanwhile, we revealed that the solvent ratio, the antisolvent flow rate, and the initial concentration of Ph_(3)COH are the main factors affecting the solid form selectivity and morphology transition. Such a novel method would be considered as a promising technique to be extended to screen and control key crystallization parameters of other substances.

关键词： Microfluidics Triphenylmethanol Antisolvent crystallization Crystal habit Solid form

Seismic safety assessment with non-Gaussian random processes for train-bridge coupled systems

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 241-260页

作者： zhao Han Gao Lei Wei Biao Tan Jincheng guo Peidong Jiang Lizhong Xiang Ping Key Laboratory of Geomechanics and Embankment Engineering of Ministry of Education Hohai UniversityNanjing 210024China School of Civil Engineering Central South UniversityChangsha 410075China

Extensive high-speed railway(HSR)network resembled the intricate vascular system of the human body,crisscrossing *** events,known for their unpredictability,pose a significant threat to both trains and bridges,given the HSR’s extended operational ***,ensuring the running safety of train-bridge coupled(TBC)system,primarily composed of simply supported beam bridges,is *** methods like the Monte Carlo method fall short in analyzing this intricate system ***,efficient algorithm like the new point estimate method combined with moment expansion approximation(NPEM-MEA)is applied to study random responses of numerical simulation TBC *** of the NPEM-MEA’s feasibility is conducted using the Monte Carlo *** analysis confirms the accuracy and efficiency of the method,with a recommended truncation order of four to six for the ***,the influences of seismic magnitude and epicentral distance are discussed based on the random dynamic responses in the TBC *** methodology not only facilitates seismic safety assessments for TBC systems but also contributes to standard-setting for these systems under earthquake conditions.

关键词： train-bridge coupled(TBC)system random vibration new point estimate method(NPEM) seismic safety assessment moment expansion approximation(MEA) non-Gaussian distributions

Benefit of aerosol reduction to winter wheat during China's clean air action:A case study of Henan Province

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Journal of Environmental Sciences 2024年第7期141卷 90-101页

作者： Yang Bai Pengfei zhao Xueyang Chen Lijun Wang Wenjuan Chang Jianzhong guo Jiayao Wang College of Geography and Environmental Science Henan UniversityKaifeng 475004China Henan Industrial Technology Academy of Spatio-Temporal Big Data Henan UniversityZhengzhou 475000China Henan Technology Innovation Center of Spatio-Temporal Big Data Henan UniversityZhengzhou 450046China Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions(Henan University) Ministry of EducationKaifeng 475000China

A strongly declining aerosol radiative effect has been observed in China since 2013 after implementing the clean air action,yet its impact on wheat(Triticum aestivum L.)production remains *** use satellite measures and a biophysical crop model to assess the impact of aerosol-induced radiative perturbations on winter wheat production in the agricultural belt of Henan province from 2013 to *** calibrating parameters with the extended Fourier Amplitude Sensitivity Test(EFAST)and the generalized likelihood uncertainty estimation(GLUE)method,the DSSAT CERES-Wheat model was able to simulate crop biomass and yield more *** found that the aerosol negatively impacted wheat biomass by 21.87%and yield by 22.48%from 2006 to 2018,and the biomass effects from planting to anthesis were more significant compared to anthesis to *** to the strict clean air action,under all-sky conditions,the surface solar shortwave radiation(SSR)in 2018 increased by about 7.08%over 2006-2013 during the wheat growing *** a result of the improvement of crop photosynthesis,winter wheat biomass and yield increased by an average of 5.46%and 2.9%,*** findings show that crop carbon uptake and yield will benefit from the clean air action in China,helping to ensure national food and health security.

关键词： Haze pollution Clean air action Aerosol-induced radiative perturbation Wheat production DSSAT model

Interpreting Larix principis-rupprechtii radial growth in northern China based on the Vaganov-Shashkin model

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Journal of Forestry Research 2024年第3期35卷 99-110页

作者： Jiachuan Wang Shuheng Li Qiang Li Yili guo Yijie Han Qi Liu Yiqi zhao College of Urban and Environmental Sciences Northwest UniversityXi'an 710127People's Republic of China Institute of Global Environmental Change Xi'an Jiaotong UniversityXi'an 710049People's Republic of China Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity Northwest UniversityXi'an 710127People's Republic of China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061People's Republic of China

Changes in annual radial growth is an important indication of climate change. Dendroclimatology studies in northern China have focused on linear statistical analysis,but lacking studies based on the process of ring formation to clarify the radial growth of trees. Tree-ring width standard chronology(STD) was established using samples of Larix principis-rupprechtii collected at 2303 m altitude on Luya Mountain. Using the Vaganov-Shashkin(VS) model to simulate growth and development, the internal physiological mechanism of radial growth is identified. It was concluded that:(1) the growing season of L. principis-rupprechtii was May to September;(2) soil moisture was a significant factor in the early and late growing seasons, and temperature was the dominant factor in its main growth period;and(3) formation of narrow ring widths was closely related to drought stress, the development of wide ring widths will be restricted by increasing future temperatures. The VS model is applicable for radial growth simulation of subalpine coniferous forests and for guiding the cultivation of local tree species in the future.

关键词： Vaganov-Shashkin model Larix principis-rupprechti Tree-ring width Annual growth