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老年2型糖尿病患者血清微小RNA-125a-3p和基质金属蛋白酶9水平与颈动脉粥样硬化的关系

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中国医药 2024年第4期19卷 545-549页

作者：江巍白盟盟王海峰内蒙古自治区人民医院干部保健所呼和浩特010010

目的探讨老年2型糖尿病(T2DM)患者血清微小RNA-125a-3p(miR-125a-3p)、基质金属蛋白酶9(MMP-9)水平与颈动脉粥样硬化(CAS)的关系。方法选取2020年4月至2023年5月内蒙古自治区人民医院收治的200例老年T2DM患者(T2DM组),根据颈动脉内中... 详细信息

目的探讨老年2型糖尿病(T2DM)患者血清微小RNA-125a-3p(miR-125a-3p)、基质金属蛋白酶9(MMP-9)水平与颈动脉粥样硬化(CAS)的关系。方法选取2020年4月至2023年5月内蒙古自治区人民医院收治的200例老年T2DM患者(T2DM组),根据颈动脉内中膜厚度(CIMT)分为CAS亚组和非CAS亚组,另选取同期45例老年体检健康者为对照组。收集T2DM患者临床资料,检测研究对象血清miR-125a-3p、MMP-9水平。分析T2DM患者血清miR-125a-3p、MMP-9水平与CIMT、空腹血糖、糖化血红蛋白(HbA1c)、甘油三酯、低密度脂蛋白胆固醇(LDL-C)的相关性,多因素Logistic回归分析T2DM患者CAS的影响因素,受试者工作特征(ROC)曲线分析血清miR-125a-3p、MMP-9对T2DM患者CAS的预测价值。结果 T2DM组血清miR-125a-3p、MMP-9水平均高于对照组[(1.58±0.30)比(1.09±0.22)、(24±8)μg/L比(14±5)μg/L](均P<0.001)。200例T2DM患者中137例CIMT≥1.0 mm, CAS发生率为68.5%(137/200)。CAS亚组miR-125a-3p、MMP-9水平均高于非CAS亚组(均P<0.05)。T2DM患者血清miR-125a-3p与MMP-9水平呈正相关(r=0.778,P<0.001),二者与CIMT、空腹血糖、HbA1c、甘油三酯、LDL-C均呈正相关(均P<0.001)。多因素Logistic回归分析结果显示,血脂异常、病程延长和HbA1c、LDL-C、miR-125a-3p、MMP-9升高为T2DM患者CAS的独立危险因素(均P<0.05)。ROC曲线分析结果显示,血清miR-125a-3p、MMP-9联合预测老年T2DM患者CAS的曲线下面积大于二者单独预测(0.864比0.799、0.796)。结论老年T2DM患者血清miR-125a-3p、MMP-9水平升高与CAS密切相关,可能成为T2DM患者CAS的辅助预测指标。

关键词： 2型糖尿病颈动脉粥样硬化微小RNA-125a-3p 基质金属蛋白酶9

Field-effect at electrical contacts to two-dimensional materials

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Nano Research 2021年第12期14卷 4894-4900页

作者： Yao Guo Yan Sun Alvin Tang Ching-Hua Wang Yanqing Zhao mengmeng bai Shuting Xu Zheqi Xu Tao Tang Sheng Wang Chenguang Qiu Kang Xu Xubiao Peng Junfeng Han Eric Pop Yang Chai School of Physics Beijing Institute of TechnologyBeijing100081China Department of Electrical Engineering and Stanford SystemX Alliance Stanford UniversityStanfordCA94305USA Advanced Manufacturing EDA Co. Ltd.Shanghai201204China Key Laboratory for the Physics and Chemistry of Nanodevices Department of ElectronicsPeking UniversityBeijing100871China Department of Applied Physics The Hong Kong Polytechnic UniversityHong KongChina

The inferior electrical contact to two-dimensional(2D)materials is a critical challenge for their application in post-silicon very large-scale integrated *** contacts were generally related to their resistive effect,quantified as contact *** a systematic investigation,this work demonstrates a capacitive metal-insulator-semiconductor(MIS)field-effect at the electrical contacts to 2D materials:The field-effect depletes or accumulates charge carriers,redistributes the voltage potential,and gives rise to abnormal current saturation and *** one hand,the current saturation hinders the devices’driving ability,which can be eliminated with carefully engineered contact *** the other hand,by introducing the nonlinearity to monolithic analog artificial neural network circuits,the circuits’perception ability can be significantly enhanced,as evidenced using a coronavirus disease 2019(COVID-19)critical illness prediction *** work provides a comprehension of the field-effect at the electrical contacts to 2D materials,which is fundamental to the design,simulation,and fabrication of electronics based on 2D materials.

关键词： field-effect electrical contact two-dimensional materials nonlinearity in-memory-computing

Interface property of dissimilar Ti-6Al-4V/AA1050 composite laminate made by non-equal channel lateral co-extrusion and heat treatment

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Defence Technology（防务技术） 2024年第3期33卷 197-208页

作者： Juan Liao mengmeng Tian Xin Xue School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou 350116China

The purpose of this paper is to examine the effect of processing parameters and subsequent heat treatments on the microstructures and bonding strengths of Ti-6Al-4V/AA1050 laminations formed via a non-equal channel lateral co-extrusion *** microstructural evolution and growth mechanism in the diffusion layer were discussed further to optimize the bonding quality by appropriately adjusting process *** electron microscopes(SEM),energy dispersive spectrometer(EDS),and X-ray diffraction(XRD)were used to characterize interfacial diffusion *** shear test was used to determine the mechanical properties of the interfacial diffusion *** experimental results indicate that it is possible to co-extrusion Ti-6Al-4V/AA1050 compound profiles using non-equal channel lateral *** heat treatment processes affect the thickness of the diffusion *** the temperature and time of heat treatment increase,the thickness of the reaction layers increases ***,the shear strength of the Ti-6Al-4V/AA1050 composite interface is proportional to the diffusion layer *** is observed that a medium interface thickness results in superior mechanical performance when compared to neither a greater nor a lesser interface *** characterization of all heat treatments reveals that the only intermetallic compound observed in the diffusion layers is TiAl_(3).Due to the inter-diffusion of Ti and Al atoms,the TiAl_(3) layer grows primarily at AA1050/TiAl_(3) interfaces.

关键词： Shear strength Co-extrusion Heat treatment Microstructure Intermetallic compounds

Carbon-based materials with combined functions of thermal management and electromagnetic protection: Preparation, mechanisms, properties, and applications

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Nano Research 2024年第3期17卷 883-903页

作者： Junwei Yue Yiyu Feng mengmeng Qin Wei Feng School of Materials Science and Engineering and Tianjin Key Laboratory of Composite and Functional Materials Tianjin UniversityTianjin 300350China

The proliferation of high-power,highly informationized,and highly integrated electronic devices and weapons equipment has given rise to increasingly conspicuous issues about electromagnetic(EM)pollution and thermal *** issues,in turn,impose constraints on the performance of such equipment and jeopardize personnel *** materials,owing to their diverse and modifiable structures,offer adjustable thermal and electric conductivity,rendering them highly promising for applications in fields such as thermal management and EM protection which have garnered extensive research and *** pursuit of integrated device and equipment development has elevated the demand for multifunctional materials,prompting significant research into carbon-based composite materials that include both thermal management and EM protection ***,there are no relevant reviews on this topic at ***,this work consolidates research findings from recent years on carbon matrix composites exhibiting dual attributes of thermal management and EM *** attributes include thermally conductive electromagnetic interference(EMI)shielding materials,thermally insulating EMI shielding materials,thermally conductive EM wave(EMW)absorbing materials,and thermally insulating EMW absorbing *** paper elucidates the fundamental principles underpinning thermal conduction,thermal insulation,EMW absorbing,and EMI ***,it engages in discussions surrounding areas of contention,design strategies,and the functional properties of various material ***,the paper concludes by presenting the challenges encountered and potential research strategies about composites endowed with both thermal management and EM protection functionalities,while also envisaging the development of novel multifunctional EM protection materials.

关键词： carbon-based composites electromagnetic interference shielding microwave absorption thermal conduction thermal insulation

Impact of dietary supplementation with β-alanine on the rumen microbial crude protein supply, nutrient digestibility and nitrogen retention in beef steers elucidated through sequencing the rumen bacterial community

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Animal Nutrition 2024年第2期17卷 418-427页

作者： Jinming Hu Shuo Zhang mengmeng Li Guangyong Zhao State Key Laboratory of Animal Nutrition College of Animal Science and Technology China Agricultural University

This study investigated the effects of β-alanine(β-Ala) on rumen fermentation, nutrient digestibility,nitrogen(N) metabolism, plasma biochemical parameters, and rumen bacterial communities in beef steers. Six steers with initial liveweight of 252.8 ± 5.2 kg and 3 treatments of supplementing with 0, 30,or 60 g β-Ala per day to basal diet were allocated in a replicated 3 × 3 Latin square design. Each experimental period was 20 d, of which the first 15 d were for adaptation and the subsequent 5 d were for sampling. The results showed that β-Ala linearly increased the ruminal concentration of microbial crude protein(MCP)(P = 0.005), but it did not affect the ruminal concentrations of ammonia N and total volatile fatty acids(P > 0.10). β-Ala also linearly increased the dry matter(DM)(P = 0.009), organic matter(OM)(P = 0.017) and crude protein(CP)(P = 0.043) digestibility, tended to decrease the acid detergent fiber digestibility(P = 0.077), but it did not affect the neutral detergent fiber digestibility(P = 0.641). β-Ala quadratically increased the relative abundance of ruminal Bacteroidota(P = 0.021) at the phylum level, and increased Prevotella(P = 0.028) and Prevotellaceae＿UCG-003(P = 0.014), and decreased the relative abundance of NK4A214＿group(P = 0.009) at the genus level. Feeding steers with β-Ala linearly increased the urinary N(P = 0.006), urea excretions(P = 0.002) and the N retention(P = 0.004), but it did not affect the N utilization efficiency(P = 0.120). β-Ala quadratically increased the plasma concentration of the total antioxidant capacity(P = 0.011) and linearly increased the plasma concentration of insulin-like growth factor-1(P < 0.001). In summary, dietary supplementation with β-Ala improved the rumen MCP supply and increased the digestibility of DM, OM, CP and the N *** research is necessary to verify the ruminal degradability of β-Ala and to investigate the mechanism of the impact of absorbed β-Ala on the anti-oxidative ability in stee

关键词： β-Alanine Cattle Nitrogen metabolism Rumen bacterial community Rumen fermentation

Consolidation of high replacement ratio stone column-reinforced ground:Analytical solutions incorporating clogging effect

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3311-3326页

作者： Jinxin Sun mengmeng Lu Baolong Xu Jie Shan School of Mechanics and Civil Engineering China University of Mining and TechnologyXuzhou221116China Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou221006China

The utilization of stone columns has emerged as a popular ground improvement strategy,whereas the drainage performance can be adversely hampered by clogging *** the ample progress of calculation methods for the consolidation of stone column-improved ground,theoretical investigations into the clogging effect have not been thoroughly ***,it is imperative to involve the column consolidation deformation to mitigate computational error on the consolidation of composite ground with high replacement *** this context,an analytical model accounting for the initial clogging and coupled time and depth-dependent clogging of stone columns is ***,the resulting governing equations and analytical solutions are obtained under a new flow continuity relationship to incorporate column consolidation *** accuracy and reliability of the proposed model are illustrated by degradation analysis and case studies with good ***,the computed results of the current study are juxtaposed against the existing models,and an in-depth assessment of the impacts of several crucial parameters on the consolidation behavior is *** results reveal that ignoring column consolidation deformation leads to an overestimate of the consolidation rate,with maximum error reaching up to 16%as the replacement ratio ***,the initial clogging also has a significant influence on the consolidation ***,the increment of depth and time-clogging factors a and b will induce a noticeable retardation of the consolidation process,particularly in the later stage.

关键词： Consolidation Composite ground Stone column Clogging effect Ground improvement Analytical model

Non-crossing Quantile Regression Neural Network as a Calibration Tool for Ensemble Weather Forecasts

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Advances in Atmospheric Sciences 2024年第7期41卷 1417-1437页

作者： mengmeng SONG Dazhi YANG Sebastian LERCH Xiang'ao XIA Gokhan Mert YAGLI Jamie M.BRIGHT Yanbo SHEN bai LIU Xingli LIU Martin Janos MAYER School of Electrical Engineering and Automation Harbin Institute of TechnologyHarbin150001China Heidelberg Institute for Theoretical Studies Schloss-Wolfsbrunnenweg 3569118HeidelbergGermany Chair of Statistical Methods and Econometrics Karlsruhe Institute of Technology(KIT)Bluecherstr.1776185KarlsruheGermany Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing100029China Solar Energy Research Institute of Singapore(SERIS) National University of Singapore(NUS)Singapore117574Singapore UK Power Networks LondonSE61NPUK China Meteorological Administration Beijing100081China Heilongjiang Meteorological Bureau Harbin150001China Department of Energy Engineering Faculty of Mechanical EngineeringBudapest University of Technology and EconomicsMűegyetem rkp.3H-1111BudapestHungary

Despite the maturity of ensemble numerical weather prediction(NWP),the resulting forecasts are still,more often than not,*** such,forecast calibration tools have become *** those tools,quantile regression(QR)is highly competitive in terms of both flexibility and predictive ***,a long-standing problem of QR is quantile crossing,which greatly limits the interpretability of QR-calibrated *** this point,this study proposes a non-crossing quantile regression neural network(NCQRNN),for calibrating ensemble NWP forecasts into a set of reliable quantile forecasts without *** overarching design principle of NCQRNN is to add on top of the conventional QRNN structure another hidden layer,which imposes a non-decreasing mapping between the combined output from nodes of the last hidden layer to the nodes of the output layer,through a triangular weight matrix with positive *** empirical part of the work considers a solar irradiance case study,in which four years of ensemble irradiance forecasts at seven locations,issued by the European Centre for Medium-Range Weather Forecasts,are calibrated via NCQRNN,as well as via an eclectic mix of benchmarking models,ranging from the naïve climatology to the state-of-the-art deep-learning and other non-crossing *** and stringent forecast verification suggests that the forecasts post-processed via NCQRNN attain the maximum sharpness subject to calibration,amongst all ***,the proposed conception to resolve quantile crossing is remarkably simple yet general,and thus has broad applicability as it can be integrated with many shallow-and deep-learning-based neural networks.

关键词： ensemble weather forecasting forecast calibration non-crossing quantile regression neural network CORP reliability diagram post-processing

Assessment of piloting behavior impact on landing risk of transport aircraft

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Chinese Journal of Aeronautics 2024年第9期37卷 178-192页

作者： Zhiyue XIONG Shuguang ZHANG Mingkai WANG Peng TANG mengmeng WANG School of Transportation Science and Engineering Beihang UniversityBeijing 102206China

The human factors and their interaction with other factors play an important role in the flight safety of transport *** this paper,a paradigm of risk assessment for transport aircraft interacting with piloting behaviors is proposed,with focus on landing which is the most accident-prone flight stage in aviation safety ***-based flight simulation serves as our data source for landing risk analysis under uncertainties.A digital pilot in the loop that reflects the human piloting behaviors is employed to facilitate simulation *** types of unsafe events in landing are identified from *** this basis,the landing safety boundary is extracted via stochastic simulation to divide safety and hazardous flight status domains,which con-tributes to flight status management and risk *** simulation results indicate that appro-priate piloting behavior,which is active response and fast target acquisition with minimum overshoot and fluctuation,shows benefit to landing *** subset simulation technique is employed to further refine the boundary with less computational ***,the effect of airspeed,windspeed,and other factors on landing risk is also *** proposed risk assess-ment method would help optimize operation procedure and develop targeted pilot training program.

关键词： Landing risk assessment Risk parameterization Human factors Piloting behavior model Landing safety boundary Subset simulation

Multivariate Time Series Anomaly Detection Based on Spatial-Temporal Network and Transformer in Industrial Internet of Things

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Computers, Materials & Continua 2024年第8期80卷 2815-2837页

作者： mengmeng Zhao Haipeng Peng Lixiang Li Yeqing Ren Information Security Center State Key Laboratory ofNetworking and Switching TechnologyBeijing University of Posts and TelecommunicationsBeijing100876China National Engineering Laboratory for Disaster Backup and Recovery Beijing University of Posts and TelecommunicationsBeijing100876China Department of Information Science and Engineering Zaozhuang UniversityZaozhuang277160China

In the Industrial Internet of Things(IIoT),sensors generate time series data to reflect the working *** the systems are attacked,timely identification of outliers in time series is critical to ensure *** many anomaly detection methods have been proposed,the temporal correlation of the time series over the same sensor and the state(spatial)correlation between different sensors are rarely considered simultaneously in these *** to the superior capability of Transformer in learning time series *** paper proposes a time series anomaly detection method based on a spatial-temporal network and an improved ***,the methods based on graph neural networks typically include a graph structure learning module and an anomaly detection module,which are ***,in the initial phase of training,since neither of the modules has reached an optimal state,their performance may influence each *** scenario makes the end-to-end training approach hard to effectively direct the learning trajectory of each *** interdependence between the modules,coupled with the initial instability,may cause the model to find it hard to find the optimal solution during the training process,resulting in unsatisfactory *** introduce an adaptive graph structure learning method to obtain the optimal model parameters and graph *** on two publicly available datasets demonstrate that the proposed method attains higher anomaly detection results than other methods.

关键词： Multivariate time series anomaly detection spatial-temporal network Transformer