检索结果-南通市图书馆

在线全文

学校读者我要写书评

暂无评论

针刺联合神经干细胞修复脊髓损伤的科学依据

中国组织工程研究 2025年第19期29卷 4111-4121页

作者：黄晓萌张芝兰尚文雅黄靖韦慧麟李冰任亚锋河南中医药大学康复医学院河南省郑州市450046 河南中医药大学第一附属医院河南省郑州市450000

背景:脊髓损伤是由创伤性或非创伤性事件引起的一种神经系统疾病,常导致损伤节段以下严重功能障碍。近年来,神经干细胞移植被认为在调控脊髓损伤后的炎症反应、抑制胶质瘢痕的过度增生以及促进神经再生方面具有显著的治疗潜力。目的:综... 详细信息

背景:脊髓损伤是由创伤性或非创伤性事件引起的一种神经系统疾病,常导致损伤节段以下严重功能障碍。近年来,神经干细胞移植被认为在调控脊髓损伤后的炎症反应、抑制胶质瘢痕的过度增生以及促进神经再生方面具有显著的治疗潜力。目的:综述并讨论针刺及神经干细胞移植疗法在抑制脊髓损伤诱导的继发性损伤中的潜在作用机制,深入探讨其治疗脊髓损伤的科学依据。方法:以“脊髓损伤,针刺,神经干细胞,SDF-1α/CXCR4轴”为中文检索词,以“Spinal cord injury,acupuncture,neural stem cells,SDF-1α/CXCR4 axis”为英文检索词,分别检索PubMed、Elsevier、万方及中国知网数据库,最终纳入96篇文献,汇总分析了针刺联合神经干细胞治疗脊髓损伤的相关研究成果,总结了这一联合疗法在治疗脊髓损伤后继发性损伤中的相关机制。结果与结论:①基质细胞衍生因子1α(stromal-derived factor 1α,SDF-1α)/CXC趋化因子受体4(chemokine receptor 4,CXCR4)轴在神经干细胞移植治疗脊髓损伤中扮演着至关重要的角色,该信号传导机制不仅影响神经干细胞的迁移、增殖和分化,更是决定干细胞归巢至损伤部位效率的关键因素。因此,针对该轴线的调控,对于提升脊髓损伤的治疗效果具有重要意义。②针刺作为一种传统中医疗法,在脊髓损伤的继发性损伤调控中展现出独特的优势,它能够通过调节炎症反应、抑制细胞凋亡、改善微循环、减少神经胶质瘢痕形成以及对抗氧化应激等多种途径,有效减轻脊髓损伤后的继发性损伤。③针刺还能够影响SDF-1α/CXCR4轴的表达与功能,从而增强神经干细胞的归巢和存活能力,促进神经再生和功能恢复。④结合针刺与干细胞移植的疗法,是一种创新且较好的脊髓损伤治疗策略,适用于修复神经环路,它结合了传统中医的智慧与现代生物技术的优势,为脊髓损伤患者提供了新的治疗选择。然而,目前这种联合疗法仍处于研究和探索阶段,其长期疗效和安全性尚需进一步验证。⑤综合而言,针刺及神经干细胞移植治疗脊髓损伤具有巨大的临床应用潜力,但仍需深入研究和优化治疗方案。未来,期待通过更多的临床试验和机制研究,进一步揭示这一疗法的疗效机制和最佳适应证,为脊髓损伤患者带来更好的康复希望和更高效的治疗效果。

关键词：针刺神经干细胞脊髓损伤继发性损伤神经再生炎症反应氧化应激神经保护基质细胞衍生因子1α(SDF-1α)/CXC趋化因子受体4(CXCR4)轴协同机制

A Fully Pipelined Probability Density Function Engine for Gaussian Copula Model

在线全文

学校读者我要写书评

暂无评论

Tsinghua Science and Technology 2014年第2期19卷 195-202页

作者： Huabin Ruan xiaomeng huang Haohuan Fu Guangwen Yang Department of Computer Science and Technology Tsinghua University Center for Earth System Science Tsinghua University

The Gaussian Copula Probability Density Function （PDF） plays an important role in the fields of finance, hydrological modeling, biomedical study, and texture retrieval. However, the existing schemes for evaluating the Gaussian Copula PDF are all computationally-demanding and generally the most time-consuming part in the corresponding applications. In this paper, we propose an FPGA-based design to accelerate the computation of the Gaussian Copula PDF. Specifically, the evaluation of the Gaussian Copula PDF is mapped into a fully-pipelined FPGA dataflow engine by using three optimization steps： transforming the calculation pattern, eliminating constant computations from hardware logic, and extending calculations to multiple pipelines. In the experiments on 10 typical large-scale data sets, our FPGA-based solution shows a maximum of 1870 times speedup over a well-tuned single- core CPU-based solution, and 610 times speedup over a well-optimized parallel quad-core CPU-based solution when processing two-dimensional data.

关键词： Gaussian Copula probability density function FPGA pipeline optimization

Deep Learning for Seasonal Precipitation Prediction over China

在线全文

学校读者我要写书评

暂无评论

Journal of Meteorological Research 2022年第2期36卷 271-281页

作者： Weixin JIN Yong LUO Tongwen WU xiaomeng huang Wei XUE Chaoqing YU Department of Earth System Science Ministry of Education Key Laboratory for Earth System ModelingInstitute for Global Change StudiesTsinghua UniversityBeijing 100084 Beijing Climate Center China Meteorological AdministrationBeijing 100081 AI for Earth Lab the Joint Laboratory of Cross-Strait Tsinghua Research InstituteXiamen 361006

Despite significant progress having been made in recent years,the forecast skill for seasonal precipitation over China remains *** this study,a deep-learning-based statistical prediction model for seasonal precipitation over China was *** model was trained to learn the distribution of the seasonal precipitation using simultaneous general circulation ***,it was pre-trained with the hindcasts of several general circulation models(GCMs),and evaluation of the test set suggested that the pre-trained model could basically reproduce the GCM-predicted precipitation,with the anomaly pattern correlation coefficients(PCCs)greater than ***,transfer learning was applied by using ECMWF Reanalysis v5(ERA5)data and gridded precipitation observational data over China,to further correct the systemic errors in the *** a result,using general circulation fields from reanalysis as the input,this hybrid model performed reasonably well in simulating the seasonal precipitation over China,with the PCC reaching *** addition,the results using the circulation fields predicted by GCMs as the input were also *** general,the proposed model improves the PCC over China by 0.10-0.13,as compared to the raw GCM outputs,for lead times of 1-4 *** deep learning model has been used at the National Climate Center of China Meteorological Administration for the past two years to provide guidance for summer precipitation prediction over China and has performed extremely well.

关键词： seasonal precipitation seasonal prediction statistical downscaling deep learning

Optimizing write operation on replica in data grid

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2011年第1期54卷 1-11页

作者： XU PengZhi,WU YongWei,huang xiaomeng, YANG GuangWen & ZHENG WeiMin Department of Computer Science and Technology,Tsinghua University,Beijing 100084,China Department of Computer Science and Technology Tsinghua University Beijing China

Replication technique can improve access performance and data availability of data grid systems. So far,most related work on data replication in data grid systems focuses on read-only *** write operations have been widely used in practice,its optimization problem has not been suciently *** this paper,we show that write requests from users can be processed by a nearest site,regardless of the location of latest written *** policy of write nearby instead of write to the latest replica can improve the performance of write operations,while inconsistency is caused between multiple ***,we propose two metadata management algorithms to make sure that users can retrieve up-to-date datasets at any *** extend OptorSim to support the implementation and evaluation of our *** results of simulation show that our scheme achieves performance gains up to 3.3 compared with WriteMaster scheme.

关键词： replication data grid simulation access latency

Disentangling land model uncertainty via Matrix-based Ensemble Model Inter-comparison Platform(MEMIP)

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Ecological Processes 2022年第1期11卷 222-237页

作者： Cuijuan Liao Yizhao Chen Jingmeng Wang Yishuang Liang Yansong huang Zhongyi Lin Xingjie Lu Yuanyuan huang Feng Tao Danica Lombardozzi Almut Arneth Daniel SGoll Atul Jain Stephen Sitch Yanluan Lin Wei Xue xiaomeng huang Yiqi Luo Department of Earth System Science Ministry of Education Key Laboratory for Earth System ModelingInstitute for Global Change StudiesTsinghua UniversityBeijingChina Joint Innovation Center for Modern Forestry Studies College of Biology and the EnvironmentNanjing Forestry UniversityNanjingChina Department of Geography University of CambridgeCambridgeUK School of Life Science Nanjing UniversityNanjingChina Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Guangdong Province Key Laboratory for Climate Change and Natural Disaster StudiesSchool of Atmospheric SciencesSun Yat-Sen UniversityGuangzhouChina CSIRO Oceans and Atmosphere Aspendale 3195Australia Terrestrial Sciences Section Climate and Global DynamicsNational Center for Atmospheric ResearchBoulderCO 80305USA Karlsruhe Institute of Technology Institute of Meteorology and Climate Research/Atmospheric Environmental ResearchGarmisch-PartenkirchenGermany UniversitéParis Saclay CEA-CNRS-UVSQLSCE/IPSLGif sur YvetteFrance Department of Atmospheric Sciences University of IllinoisUrbanaILUSA College of Life and Environmental Sciences University of ExeterExeterUK Department of Computer Science and Technology Tsinghua UniversityBeijingChina Center for Ecosystem Science and Society Department of Biological SciencesNorthern Arizona UniversityFlagstaffAZUSA

Background:Large uncertainty in modeling land carbon(C)uptake heavily impedes the accurate prediction of the global C *** the uncertainty sources among models is crucial for model improvement yet has been difficult due to multiple feedbacks within Earth System Models(ESMs).Here we present a Matrix-based Ensemble Model Inter-comparison Platform(MEMIP)under a unified model traceability framework to evaluate multiple soil organic carbon(SOC)*** the MEMIP,we analyzed how the vertically resolved soil biogeochemistry structure influences SOC prediction in two soil organic matter(SOM)*** comparing the model outputs from the C-only and CN modes,the SOC differences contributed by individual processes and N feedback between vegetation and soil were explicitly ***:Results showed that the multi-layer models with a vertically resolved structure predicted significantly higher SOC than the single layer models over the historical simulation(1900–2000).The SOC difference between the multi-layer models was remarkably higher than between the single-layer *** analysis indicated that over 80%of the SOC increase in the multi-layer models was contributed by the incorporation of depth-related processes,while SOC differences were similarly contributed by the processes and N feedback between models with the same soil depth ***:The output suggested that feedback is a non-negligible contributor to the inter-model difference of SOC prediction,especially between models with similar process *** analysis with TRENDY v7 and more extensive MEMIP outputs illustrated the potential important role of multi-layer structure to enlarge the current ensemble spread and the necessity of more detail model decomposition to fully disentangle inter-model *** stressed the importance of analyzing ensemble outputs from the fundamental model structures,and holding a holistic view in understanding the en

关键词： Soil organic carbon Inter-model comparison Uncertainty analysis Carbon-nitrogen coupling Vertical resolved soil biogeochemistry structure

Aluminium-based moderate temperature filler metals for vacuum brazing of 6061 aluminium alloy

在线全文

学校读者我要写书评

暂无评论

China Welding 2021年第3期30卷 59-64页

作者： Zhang Guoqing Li Bin Wang Wei huang xiaomeng Yuan Linlin Beijing Non-Ferrus Metals and Rare Earth Research Institute Beijing 100012China Beijing Engineering Research Center of New Brazing Materaials for Electronic Information Beijing 100012China

Four kinds of aluminum based moderate temperature filler metals used for vacuum brazing of 6061 aluminum alloy were prepared by rapid solidification-isothermal *** effects of alloy elements content on the melting characteristics of filler metals was studied by Differential Scanning Calorimetry(DSC).The microstructures of the filler metals and brazed joints were observed by scanning electron microscopy(SEM)and energy dispersive spectrometer(EDS).The results show that with the increase of Cu content into the filler metals,the liquid phase temperature gradually is *** characterzation of the brazed joints shows the eutectic structure of(α+β)and(α+θ)decrease gradually,θ-CuAl_(2)(Ni)gradually increases and transforms from small fishbone shapes to block *** shear strength of 83 MPa for the 6061 aluminum joint with Al-9.5Si-10Cu-2Ni-0.5Mg was achieved after brazing at 575℃for 2 min.

关键词： moderate temperature filler metal Al-Cu-Si-Ni-Mg θ-CuAl_(2)(Ni) vacuum brazing

Simultaneous characterization of the atmospheres,surfaces,and exomoons of nearby rocky exoplanets

在线全文

学校读者我要写书评

暂无评论

Earth and Planetary Physics 2018年第3期2卷 247-256页

作者： WenLiang Cui JinSu Zhang Frederic Schmidt Duo Cui xiaomeng huang Tong Li Feng Tian Ministry of Education Key Laboratory for Earth System Modeling Department for Earth System ScienceTsinghua University Department of Physics Tsinghua University GEOPS Univ.Paris-SudCNRSUniversité Paris-Saclay

Atmospheric composition is an important indicator of habitability and *** presence or absence of a large exomoon around an Earth-size exoplanet could have important consequences for planet climate *** the detection of exomoons and retrieval of information regarding atmospheric composition of Earth-size exoplanets are important goals of future exoplanet *** a data analysis method is developed to achieve both goals simultaneously,based on reflection spectra of exoplanet-exomoon *** show that the existence of exomoons,the size of exomoons,and the concentrations of some atomic and molecular species in the atmospheres of their hosting Earth-like exoplanets can be retrieved with high levels of *** addition,the method can provide well-constrained fractions of basic surface types on the targets because of the characteristic spectral features of atmospheric species and surface types in the analyzed spectral range.

关键词： exoplanet biosignature exomoon

Joining of activated graphite to 6063 aluminum alloy with Al-Cu-Si-Ni-Mg filler metal

在线全文

学校读者我要写书评

暂无评论

China Welding 2020年第4期29卷 60-64页

作者： Yuan Linlin huang xiaomeng Chen Xiaoyu Qi Yuefeng Beijing Non-ferrous Metals and Rare Earth Research Institute Beijing 100012China Beijing Engineering Research Center of New Brazing Materials for Electronic Information Beijing 100012China

In this work, 6063 aluminum alloy-graphite joint intended for thermal conductive application were realized by applying Al-CuSi-Ni-Mg brazing filler metal and Ag-Cu-Ti pasted on high density graphite substrate to ensure wetting during the brazing process. The interface reactions during brazing and mechanical properties were studied using scanning electron microscopy(SEM) and shear test *** was formed at the graphite/active Ag-Cu-Ti paste interface due to the reaction between Ti and C, and thus the wettability on the graphite was *** is shown that joint with a good quality can be produced at a brazing temperature of 550 ℃ for 10 *** average tensile strength of the joint is 21 MPa. thus the wettability on the graphite was *** is shown that joint with a good quality can be produced at a brazing temperature of 550 ℃ for 10 min.

关键词： graphite aluminum alloy metallization reactive brazing

Brazing of 5A01 aluminum alloy using Al-Cu-Si-Ni filler metal

在线全文

学校读者我要写书评

暂无评论

China Welding 2018年第4期27卷 41-45页

作者： Yuan Linlin Shi Xiumei Liu Xu Qi Yuefeng huang xiaomeng Non-ferrous Metals and Rare Earth Research Institute Beijing Beijing Engineering Research Center of New Brazing Materials for Electronic Information

The vacuum brazing of 5 A01 aluminum alloy using Al-Cu-Si-Ni filler metal was investigated at 550 ℃ and 560 ℃,respectively. Microstructure and properties of brazed 5 A01 alloy joints were investigated by tensile-shear tests and scanning electron microscopy analysis. The effects of brazing temperature and holding time on the shear strength and microstructure of the joints were studied. The results show that the different intermetallic compounds such as Al-Cu-Ni and Mg_2 Si formed in the bonding area. Shear strength increased with holding time and brazing temperature. The average shear strengths increased from 42. 3 MPa brazed at 550 ℃for 5 min to 68 MPa brazed at 560 ℃ for 15 min. Discontinuous cracks were found in the joint brazed at 550 ℃ for 5 min,and the joint showed poor shear strength. high shear strength were obtained in the joints brazed at 560 ℃ for 15 min.

关键词： aluminum brazing microstructure mechanical properties