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Friction 2024年第1期12卷 74-94页

作者： Jiabao yin Chun lu Jiliang MO School of Mechanical Engineering Southwest Jiaotong UniversityChengdu 610031China Technology and Equipment of Rail Transit Operation and Maintenance Key Laboratory of Sichuan Province Chengdu 610031China

A comprehensive modeling strategy for studying the thermomechanical tribological behaviors is proposed in this work.The wear degradation considering the influence of temperature(T)is predicted by Archard wear model with the help of the UMESHMOTION subroutine and arbitrary Lagrangian–Eulerian(ALE)remeshing technique.Adopting the proposed method,the thermomechanical tribological behaviors of railway vehicle disc brake system composed of forged steel brake disc and Cu-based powder metallurgy(PM)friction block are studied systematically.The effectiveness of the proposed methodology is validated by experimental test on a self-designed scaled brake test bench from the perspectives of interface temperature,wear degradation,friction noise and vibration,and contact status evolution.This work can provide an effective way for the investigation of thermomechanical tribological behaviors in the engineering field.

关键词： tribological behaviors thermomechanical field wear prediction finite element simulation disc brake system railway vehicle

An artificial intelligence diabetes managgement architecture based on 5G

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Digital Communications and Networks 2024年第1期10卷 75-82页

作者： Ruochen Huang Wei Feng shan lu Tao shan Changwei Zhang Yun Liu Department of Geriatrics The First Afiliated Hospital of Nanjing Medical UniversityNanjing210096China Department of Information The First Afliated Hospital of Nanjing Medical UniversityNanjing210096China Departnent of Medical Informatics School of Biomedical Engineering and InfomaticsNanjing Medical UniversityNanjing211166China Department of Outpatient The First Afliated Hospital of Nanjing Medical UniversityNanjing210096China Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and TelecommunicationsNanjing210003China

Along with the development of 5G network and Internet of Things technologies,there has been an explosion in personalized healthcare systems.When the 5G and Artificial Intelligence(Al)is introduced into diabetes management architecture,it can increase the efficiency of existing systems and complications of diabetes can be handled more effectively by taking advantage of 5G.In this article,we propose a 5G-based Artificial Intelligence Diabetes Management architecture(AIDM),which can help physicians and patients to manage both acute complications and chronic complications.The AIDM contains five layers:the sensing layer,the transmission layer,the storage layer,the computing layer,and the application layer.We build a test bed for the transmission and application layers.Specifically,we apply a delay-aware RA optimization based on a double-queue model to improve access efficiency in smart hospital wards in the transmission layer.In application layer,we build a prediction model using a deep forest algorithm.Results on real-world data show that our AIDM can enhance the efficiency of diabetes management and improve the screening rate of diabetes as well.

关键词： Diabetes 5G Artificial intelligence Deep forest Smart hospital ward

Adsorptive interaction between typical VOCs and various topological zeolites:Mixture effect and mechanism

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Journal of Environmental Sciences 2024年第2期136卷 626-636页

作者： Bo Yu Hua Deng Yuqin lu Tingting Pan Wenpo shan Hong He Center for Excellence in Regional Atmospheric Environment and Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Adsorption is one of the most feasible and effective methods to alleviate the volatile organic compounds(VOCs)pollution.However,the mixture effect and mechanism for competitive adsorption of VOCs on zeolites are barely addressed.In this study,toluene,acetone,and ethyl acetate as prevalent VOCs species were removed by four potential zeolites(13X,USY,Beta,ZSM-5)in both single-and multi-component systems.The structure-property relationship between adsorbate-adsorbent pairs was revealed by X-ray diffraction,scanning electron microscopy,energy dispersive spectrometer,X-ray fluorescence,N_(2) adsorption and density function theory calculation.The molecular polarity and volatility of VOCs species played key roles in adsorption and the dynamic uptakes were generally listed as follows:ethyl acetate>toluene>acetone.As for the above VOCs mixtures,13X zeolite selectively adsorbed oxygenated VOCs rather than toluene.In contrast,USY exhibited a preference to trap toluene.Ethyl acetate could be readily enriched by ZSM-5 and Beta selectively.The possible explanations and implications are discussed based on the subtle change in electron density.The results obtained are vital for understanding the mixture effect of VOCs adsorption and may guide the selection of proper adsorbent for real applications.

关键词： Adsorption Zeolites VOCs Mixture effect DFT

Joint Optimization of Resource Allocation and Trajectory Based on User Trajectory for UAV-Assisted Backscatter Communication System

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China Communications 2024年第2期21卷 197-209页

作者： Peizhong Xie Junjie Jiang Ting Li yin lu School of Communication and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China Key Lab of Broadband Wireless Communication and Sensor Network Technology(Nanjing University of Posts and Telecommunications) Ministry of EducationNanjing 210003China

The Backscatter communication has gained widespread attention from academia and industry in recent years. In this paper, A method of resource allocation and trajectory optimization is proposed for UAV-assisted backscatter communication based on user trajectory. This paper will establish an optimization problem of jointly optimizing the UAV trajectories, UAV transmission power and BD scheduling based on the large-scale channel state signals estimated in advance of the known user trajectories, taking into account the constraints of BD data and working energy consumption, to maximize the energy efficiency of the system. The problem is a non-convex optimization problem in fractional form, and there is nonlinear coupling between optimization variables.An iterative algorithm is proposed based on Dinkelbach algorithm, block coordinate descent method and continuous convex optimization technology. First, the objective function is converted into a non-fractional programming problem based on Dinkelbach method,and then the block coordinate descent method is used to decompose the original complex problem into three independent sub-problems. Finally, the successive convex approximation method is used to solve the trajectory optimization sub-problem. The simulation results show that the proposed scheme and algorithm have obvious energy efficiency gains compared with the comparison scheme.

关键词： energy efficiency joint optimization UAV-assisted backscatter communication user trajectory

Immediate implantation of ultrafine fiber slow-release system based on cell electrospinning to induce osteogenesis of mesenchymal stem cells

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Regenerative Biomaterials 2024年第2期3卷 76-87页

作者： Tao lu Long Yang Zhuoyang Li yin Liu Shun'en Xu Chuan Ye Department of Orthopaedics The Affliated Hospital of Guizhou Medical UniversityGuiyang 550004China Department of Orthopaedics The First People's Hospital of GuiyangGuiyang 550004China Center for Tissue Engineering and Stem Cell Research Guizhou Medical UniversityGuiyang 550004China Department of Otolaryngology Head and Neck Surgery Xinqiao HospitalArmy Medical University(Third Military Medical University)Chongqing 400037China Department of Dental implant Stomatological Hospital of GuiyangGuiyang 550000China

This study presents the development and evaluation of a poly(3-hydroxybutyrate-co-4-hydroxybutyrate)(P34HB)ultrafine fiber slow-release system for in vivo osteogenic induction of human umbilical cord mesenchymal stem cells(HUCMSCs).Utilizing dual-nozzle and cell electrospinning techniques,the system encapsulates L-ascorbic acid-2-phosphate magnesium(AsP),βB-glycerophosphate sodium and dexamethasone(DEX)within the'fbers,ensuring sustained osteogenic differentiation.The scaffold's morphology,characterization,hydrophilicity,mechanical properties and cellular behavior were examined.Immediate subcutaneous implantation in rabbits was con-ducted to observe its ectopic osteogenic induction effect.Successfully fabricated P34HB ultrafine fiber slow-release sys-tem.Charact ization med.theuniform distribution of HUCMSCs and inducing components within the scaffold,with no chemical reactions affecting the active components.In vitro tests showcased a prolonged release of DEX and ASP,while biocompatibility assays highlighted the scaffold's suitability for cellular growth.Alizarin Red,type I collagen,and osteopontin(OPN)staining verifed the scaffold's potent osteogenic induction effect on HUCMsCs.Notably,immediate implantation into New Zealand White rabbits led to significant new bone formation within 8 weeks.These findings underscore the system's potential for immediate in vivo implantation without prior in vitro induction,marking a promising advancement in bone tissue engineering.

关键词： bone tissue engineering cell electrospinning in vivo induction immediate implantation biomaterials

KAT7/HMGN1 signaling epigenetically induces tyrosine phosphorylation-regulated kinase 1A expression to ameliorate insulin resistance in Alzheimer’s disease

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World Journal of Psychiatry 2024年第3期14卷 445-455页

作者： Qun-shan lu Lin Ma Wen-Jing Jiang Xing-Bang Wang Mei lu Department of Geriatric Medicine Qilu Hospital of Shandong UniversityJinan 250012Shandong ProvinceChina Key Laboratory of Cardiovascular Proteomics of shandong Province Qilu Hospital of Shandong UniversityJinan 250012Shandong ProvinceChina

BACKGROUND Epidemiological studies have revealed a correlation between Alzheimer’s disease(AD)and type 2 diabetes mellitus(T2D).Insulin resistance in the brain is a common feature in patients with T2D and AD.KAT7 is a histone acetyltransferase that participates in the modulation of various genes.AIM To determine the effects of KAT7 on insulin patients with AD.METHODS APPswe/PS1-dE9 double-transgenic and db/db mice were used to mimic AD and diabetes,respectively.An in vitro model of AD was established by Aβstimulation.Insulin resistance was induced by chronic stimulation with high insulin levels.The expression of microtubule-associated protein 2(MAP2)was assessed using immunofluorescence.The protein levels of MAP2,Aβ,dual-specificity tyrosine phosphorylation-regulated kinase-1A(DYRK1A),IRS-1,p-AKT,total AKT,p-GSK3β,total GSK3β,DYRK1A,and KAT7 were measured via western blotting.Accumulation of reactive oxygen species(ROS),malondialdehyde(MDA),and SOD activity was measured to determine cellular oxidative stress.Flow cytometry and CCK-8 assay were performed to evaluate neuronal cell death and proliferation,respectively.Relative RNA levels of KAT7 and DYRK1A were examined using quantitative PCR.A chromatin immunoprecipitation assay was conducted to detect H3K14ac in DYRK1A.RESULTS KAT7 expression was suppressed in the AD mice.Overexpression of KAT7 decreased Aβaccumulation and MAP2 expression in AD brains.KAT7 overexpression decreased ROS and MDA levels,elevated SOD activity in brain tissues and neurons,and simultaneously suppressed neuronal apoptosis.KAT7 upregulated levels of p-AKT and p-GSK3βto alleviate insulin resistance,along with elevated expression of DYRK1A.KAT7 depletion suppressed DYRK1A expression and impaired H3K14ac of DYRK1A.HMGN1 overexpression recovered DYRK1A levels and reversed insulin resistance caused by KAT7 depletion.CONCluSION We determined that KAT7 overexpression recovered insulin sensitivity in AD by recruiting HMGN1 to enhance DYRK1A acetylation.Our findings suggest that KAT7 is a novel and

关键词： Alzheimer's disease Diabetes Insulin resistance KAT7 Dual-specificity tyrosine phosphorylation-regulated kinase-1A HMGN1

Mitigation of Deane and Hamill phenomenon in gallium nitride high-voltage power supply for electric propulsion system application

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High Voltage 2024年第1期9卷 252-265页

作者： Minghai Dong Hui Li shan yin Kye Yak See yingzhe Wu Xiong Xin School of Aeronautics&Astronautics University of Electronic Science and Technology of ChinaChengduChina School of Electrical&Electronic Engineering Nanyang Technological UniversitySingaporeSingapore School of Automation Engineering University of Electronic Science and Technology of ChinaChengduChina Innoscience(Shenzhen)Semiconductor Co.Ltd. ShenzhenChina

The step-up resonant converters are widely adopted to provide high voltage in kV-level for electric propulsion system due to their high efficiency,low mass,modularisation,and high-power density.The bipolar Cockcroft-Walton voltage multiplier(BiCWVM)is a major circuit that steps up the voltage in the resonant converter.However,the diode nonlinearity in BiCWVM can introduce self-sustained quasi-periodic oscillations in the voltage and current waveforms,which is commonly known as the Deane and Hamill(DH)phenomenon.The oscillation can lead to higher magnetic loss and control failure,and it is more likely to present in the gallium nitride-based converter due to the highfrequency operation.The authors aim to investigate and mitigate the DH phenomenon systematically so that proper mitigation can be implemented.To facilitate the investigation,the circuit before the BiCWVM in the converter is derived and modelled as a voltage source v_(m)and a series inductor L_(sy).Also,the reverse recovery process of the diode in the BiCWVM can be represented by a piecewise-linear(PWL)model,with the simplified circuit and PWL model,the relationship between voltage and current under different operating conditions can be determined with ease.The relationship allows to understand the mechanism of diode reverse recovery in BiCWVM that leads to DH phenomenon.Finally,a hybrid-/full-silicon carbide(SiC)design is proposed to mitigate the DH phenomenon,which is verified experimentally for a 300-kHz,5-W,20-V/1.5-kV GaN-based step-up resonant converter.

关键词： power resonant high

Effects of land-use patterns on soil microbial diversity and composition in the Loess Plateau,China

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Journal of Arid Land 2024年第3期16卷 415-430页

作者： ZHANG Jian GUO Xiaoqun shan Yujie lu Xin CAO Jianjun College of Geography and Environmental Science Northwest Normal UniversityLanzhou 730070China

In the Loess Plateau of China,land-use pattern is a major factor in controlling underlying biological processes.Additionally,the process of land-use pattern was accompanied by abandoned lands,potentially impacting soil microbe.However,limited researches were conducted to study the impacts of land-use patterns on the diversity and community of soil microorganisms in this area.The study aimed to investigate soil microbial community diversity and composition using high-throughput deoxyribonucleic acid(DNA)sequencing under different land-use patterns(apricot tree land,apple tree land,peach tree land,corn land,and abandoned land).The results showed a substantial difference(Pshannon index.While fungal beta-diversity was not considerably impacted by land-use patterns,fungal alpha-diversity indices varied significantly.The relative abundance of Actinobacteriota(34.90%),Proteobacteria(20.65%),and Ascomycota(77.42%)varied in soils with different land-use patterns.Soil pH exerted a dominant impact on the soil bacterial communities'composition,whereas soil available phosphorus was the main factor shaping the soil fungal communities'composition.These findings suggest that variations in land-use pattern had resulted in changes to soil properties,subsequently impacting diversity and structure of microbial community in the Loess Plateau.Given the strong interdependence between soil and its microbiota,it is imperative to reclaim abandoned lands to maintain soil fertility and sustain its function,which will have significant ecological service implications,particularly with regards to soil conservation in ecologically vulnerable areas.

关键词： abandoned lands land-use pattern soil property diversity of soil microbe soil microbial community

Prediction and driving factors of forest fire occurrence in Jilin Province,China

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Journal of Forestry Research 2024年第1期35卷 58-71页

作者： Bo Gao Yanlong shan Xiangyu Liu Sainan yin Bo Yu Chenxi Cui Lili Cao Wildland Fire Prevention and Fighting Innovation Center of Beihua University Forestry College of Beihua University3999 Binjiang East RoadJilin City 132013People’s Republic of China

Forest fires are natural disasters that can occur suddenly and can be very damaging,burning thousands of square kilometers.Prevention is better than suppression and prediction models of forest fire occurrence have developed from the logistic regression model,the geographical weighted logistic regression model,the Lasso regression model,the random forest model,and the support vector machine model based on historical forest fire data from 2000 to 2019 in Jilin Province.The models,along with a distribution map are presented in this paper to provide a theoretical basis for forest fire management in this area.Existing studies show that the prediction accuracies of the two machine learning models are higher than those of the three generalized linear regression models.The accuracies of the random forest model,the support vector machine model,geographical weighted logistic regression model,the Lasso regression model,and logistic model were 88.7%,87.7%,86.0%,85.0%and 84.6%,respectively.Weather is the main factor affecting forest fires,while the impacts of topography factors,human and social-economic factors on fire occurrence were similar.

关键词： Forest fire Occurrence prediction Forest fire driving factors Generalized linear regression models Machine learning models

Combined effects of sea urchin-like structure and mixed Cu^(+)/Cu^(0)states on promoting C_(2)formation in electrocatalytic CO_(2)reduction

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Frontiers of Chemical Science and Engineering 2024年第3期18卷 63-73页

作者： Mengqing shan Dongsheng lu Jiatong Dong Shen Yan Jinyu Han Hua Wang Collaborative Innovation Center of Chemical Science and Engineering Key Laboratory for Green Chemical Technology of the Ministry of EducationSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin300354China

Surface engineering and Cu valence regulation are essential factors in improving the C_(2)selectivity during the electrochemical reduction of CO_(2).Herein,we present a sea urchin-like CuO/Cu_(2)O catalyst derived from rhombic dodecahedra Cu_(2)O through one-step oxidation/etching method where the mixed Cu^(+)/Cu^(0)states are formed via in situ reduction during electrocatalysis.The combined effects of the morphology and the mixed Cu^(+)/Cu^(0)states on C–C coupling are evaluated by the Faradaic efficiency of C_(2)and the C_(2)/C1 ratio obtained in an H-cell.R-Cu^(O)/Cu_(2)O exhibited 49.5%Faradaic efficiency of C_(2)with a C_(2)/C1 ratio of 3.1 at−1.4 V vs.reversible hydrogen electrode,which are 1.5 and 3.2 times higher than those of R-Cu_(2)O,respectively.Using a flow-cell,68.0%Faradaic efficiency of C_(2)is achieved at a current density of 500 mA·cm^(−2).The formation of the mixed Cu^(+)/Cu^(0)states was confirmed by in situ Raman spectra.Additionally,the sea urchin-like structure provides more active sites and enables faster electron transfer.As a result,the excellent C_(2)production on R-CuO/Cu_(2)O is primarily attributed to the synergistic effects of the sea urchin-like structure and the stable mixed Cu^(+)/Cu^(0)states.Therefore,this work presents an integrated strategy for developing Cu-based electrocatalysts for C_(2)production through electrochemical CO_(2)reduction.

关键词： CO_(2)electrolysis sea urchin-like structure Cu^(+)/Cu^(0) C_(2)products