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数学学报（中文版） 2006年第6期49卷 1403-1410页

作者：吴鉴洪陈学琴华东师范大学统计系上海200062 宜春学院江西336000

研究了线性模型在不等式约束条件下齐次和非齐次线性估计的可容许性,刻画了两者之间的关系,得到了不等式约束条件下非齐次线性估计可容许性的充要条件．

关键词：可容许性不等式约束齐次/非齐次线性估计

High-dense nanocrystalline W-based alloy prepared by hot isostatic pressing with uniform microstructure, ultrahigh hardness and good thermal stability

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Tungsten 2025年第1期7卷 120-136页

作者： Zao-Ming wu Lin He Lin-Sen Ye Xiao-Feng Yang Jia-Jia Zhang hong-Bo Lei Institute of Materials China Academy of Engineering Physics

High-density uniform microstructure nanocrystalline W-10wt.% Cr-5wt.% Y（W-10Cr-5Y） alloy with an average grain size of 85 nm and a relative density of 99.8% was successfully prepared.W-Cr-Y alloys with different amounts of second-phase particles were prepared by high-energy ball milling and hot isostatic pressing *** effects of composition design,ball milling parameters,and sintering parameters on the microstructure of W-Cr-Y alloys were studied.A feasible technology for controlling the synthesis of high-density nanocrystalline W-based alloys has been *** microstructure analysis of nanocrystalline W-10Cr-5Y alloy shows that there are two types of doping in the second phase:intergranular doping and intragranular *** "uniform distribution YOx-rich particles" effectively suppresses the grain growth of W and leads to the formation of nanocrystalline W-10Cr-5Y alloy.W-10Cr-5Y has an ultra-high hardness,with a Vickers hardness of 1312±12 kgf·***-temperature annealing treatment shows that W-10Cr-5Y has good thermal stability at 1000 and1100℃,as demonstrated by the comparison of Vickers hardness and grain size between annealed and unannealed alloys.

关键词： Hot isostatic pressing Microstructure Nanocrystalline tungsten Thermal stability Vickers hardness

Optical and Electrical Properties of Polyimide Thin Films Grown by Vapor Deposition Polymerization

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Semiconductor Photonics and Technology 2001年第4期7卷 212-216,234页

作者： XIAO Min, ZHENG jian bang, wu hong cai (School of Electron. and Inform. Eng., Xi’an Jiaotong University, Xi’an 710049, CHN) 西安交通大学电子与信息工程学院陕西西安 710049

Using pyromellitic dianhydride (PMDA) and 4,4’ diaminodiphenyl ether (ODA) as monomer materials, polyimide thin films have been prepared onto glass substrate by vapor deposition polymerization under a vacuum of 2.666×10 -3 Pa and thermal curing of polyamic acid film in a vacuum at temperature of 150～200 ℃ for 60 min. In this process, the polymerization can be carried out through controlling the stoichiometric ratio, heating time and deposition ratio of the two monomers. The composition, the structure and properties of the polyimide films are investigated with IR spectrum, XRD, and SEM methods. The results show that the polyimide films by vapor deposition polymerization have good electrical properties and thermal stability. Therefore, the vapor deposition polymerization process is considered as a possible method of polymerization for other polymers.

关键词： Nonlinear optical materials Polyimide Vapor deposition polymerization

Stable copper boron–imidazolate cage as Cu-riched enzyme for highly efficient electrocatalytic CO2 reduction to ethylene

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Science China Chemistry 2025年

作者： Jun-Qiang Chen Qiao-hong Li Qin-Long hong Ping Shao Hai-Xia Zhang jian Zhang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences

Single-atom catalyst has garnered widespread attention to mimic mature enzymes due to its well-defined atomic structure and coordination environments. However, since the carbon–carbon（C–C） coupling reactions require synergistic catalysis of multiple sites, single-atom catalysts suffer from insufficient active sites and unclear reaction mechanisms. Controlling the reaction intermediates in a precisely targeted pocket through careful metal–organic cage design is therefore crucial. Here, we prepare a tetrahedral [Cu6L4]-type boron–imidazolate cage integrating highly active Cu sites and optimized cavity, which exhibits enzyme like specific catalytic performance in electrochemical CO2reduction reaction（CO2RR） to enhance the selectivity of *** analyses and computational calculations suggest that the single Cu site together with neighboring boron–imidazolate ligands provides suitably synergistic effects that enable the energetically favorable formation of an *COCHO intermediate, a key step determining selectivity. As a result, the [Cu6L4]-type cage of BIC-145 achieves a Faradaic efficiency of 28% for C2H4maintaining an average current density of -3.54 mA cm-2over a 5-hour electrolysis period. This work represents the first example for studying single-metal site catalysts with ultra-low coordination numbers through the rational design of metal–organic cages.

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Insights into spinal muscular atrophy from molecular biomarkers

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Neural Regeneration Research 2025年第7期20卷 1849-1863页

作者： Xiaodong Xing Xinzhu Liu Xiandeng Li Mi Li Xian wu Xiaohui Huang Ajing Xu Yan Liu jian Zhang Department of Clinical Pharmacy Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghaiChina College of Pharmacy Chongqing Medical UniversityChongqingChina

Spinal muscular atrophy is a devastating motor neuron disease characterized by severe cases of fatal muscle *** is one of the most common genetic causes of mortality among infants aged less than 2 *** research is currently receiving more attention,and new candidate biomarkers are constantly being *** review initially discusses the evaluation methods commonly used in clinical practice while briefly outlining their respective pros and *** also describe recent advancements in research and the clinical significance of molecular biomarkers for spinal muscular atrophy,which are classified as either specific or non-specific *** review provides new insights into the pathogenesis of spinal muscular atrophy,the mechanism of biomarkers in response to drug-modified therapies,the selection of biomarker candidates,and would promote the development of future ***,the successful utilization of biomarkers may facilitate the implementation of gene-targeting treatments for patients with spinal muscular atrophy.

关键词： biomarkers disease progression gene-targeting therapy neurofilaments Nusinersen spinal muscular atrophy(SMA) survival motor neuron therapeutic evaluation treatment outcomes

低空摄影技术在矿山地质灾害应急测绘中的应用研究

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世界有色金属 2020年第11期45卷 114-115页

作者：洪剑武福建省地质测绘院福建福州350000

无人机低空摄影技术能够在第一时间高效、高准确度、高分辨率的获取灾区地物信息,可以很好地应用在范围比较广的灾后救援和灾情评估。本文设计方法获得的重叠影像精确率相比与传统设计不仅在百分之九十四以上,且获得的影像数据分辨率表... 详细信息

无人机低空摄影技术能够在第一时间高效、高准确度、高分辨率的获取灾区地物信息,可以很好地应用在范围比较广的灾后救援和灾情评估。本文设计方法获得的重叠影像精确率相比与传统设计不仅在百分之九十四以上,且获得的影像数据分辨率表现稳定,满足灾区灾害应急测绘地图比例尺1:3500的影像数据标准。

关键词：低空摄影矿山地质灾害应急测绘

Clinical and Angiographic Predictors of Major Side Branch Occlusion after Main Vessel Stenting in Coronary Bifurcation Lesions

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Chinese Medical Journal 2015年第11期128卷 1471-1478页

作者： Dong Zhang Bo Xu Dong Yin Yi-Ping Li Yuan He Shi-Jie You Shu-Bin Qiao Yong-jian wu hong-Bing Yan Yue-Jin Yang Run-Lin Gao Ke-Fei Dou Department of Cardiology State Key Laboratory of Cardiovascular Disease Cardiovascular Institute Fuwai Hospital and National Center for Cardiovascular Diseases Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100037 China

Background： Major side branch （SB） occlusion is one of the most serious complications during percutaneous coronary intervention （PCI） for bifurcation lesions. We aimed to characterize the incidence and predictors of major SB occlusion during coronary bifurcation intervention. Methods： We selected consecutive patients undergoing PCI （using one stent or provisional two stent strategy） for bifurcation lesions with major SB. All clinical characteristics, coronary angiography findings, PCI procedural factors and quantitative coronary angiographic analysis data were collected. Multivariate logistic regression analysis was performed to identify independent predictors of SB occlusion. SB occlusion after main vessel （MV） stenting was defined as no blood flow or any thrombolysis in myocardial infarction （TIMI） flow grade decrease in SB after MV stenting. Results： Among all 652 bifurcation lesions, 32 （4.91%） SBs occluded. No blood flow occurred in 18 lesions and TIMI flow grade decreasing occurred in 14 lesions. In multivariate analysis, diameter ratio between MV/SB （odds ratio [OR]： 7.71,95% confidence interval [C/]： 1.53-38.85, P = 0.01）, bifurcation angle （OR： 1.03, 95% CI： 1.02-1.05, P 〈 0.01）, diameter stenosis of SB before MV stenting （OR： 1.05, 95% CI： 1.03-1.07, P〈 0.01）, TIMI flow grade of SB before MV stenting （OR： 3.59, 95% CI： 1.48-8.72, P〈 0.01） and left ventricular eject fraction （LVEF）（OR： 1.06, 95% Cl： 1.02-1.11, P 〈 0.01） were independent predictors of SB occlusion. Conclusions： Among clinical and angiographic findings, diameter ratio between MV/SB, bifurcation angle, diameter stenosis of SB before MV stenting, TIMI flow grade of SB before MV stenting and LVEF were predictive of major SB occlusion after MV stenting.

关键词： Coronary Bifurcation Lesions Major Side Branch Occlusion Percutaneous Coronary Intervention

Regulation and function of endoplasmic reticulum autophagy in neurodegenerative diseases

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Neural Regeneration Research 2025年第1期20卷 6-20页

作者： Xiu-Yun Zhao De-En Xu Ming-Lei wu Ji-Chuan Liu Zi-Ling Shi Quan-hong Ma Department of Neurology and Clinical Research Center of Neurological Disease the Second Affiliated Hospital of Soochow UniversitySuzhouJiangsu ProvinceChina Institute of Neuroscience&jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psycho-Diseases Soochow UniversitySuzhouJiangsu ProvinceChina Department of Neurology Jiangnan University Medical CenterWuxiJiangsu ProvinceChina

The endoplasmic reticulum,a key cellular organelle,regulates a wide variety of cellular *** reticulum autophagy,one of the quality control systems of the endoplasmic reticulum,plays a pivotal role in maintaining endoplasmic reticulum homeostasis by controlling endoplasmic reticulum turnover,remodeling,and *** this review,we briefly describe the endoplasmic reticulum quality control system,and subsequently focus on the role of endoplasmic reticulum autophagy,emphasizing the spatial and temporal mechanisms underlying the regulation of endoplasmic reticulum autophagy according to cellular *** also summarize the evidence relating to how defective or abnormal endoplasmic reticulum autophagy contributes to the pathogenesis of neurodegenerative *** summary,this review highlights the mechanisms associated with the regulation of endoplasmic reticulum autophagy and how they influence the pathophysiology of degenerative nerve *** review would help researchers to understand the roles and regulatory mechanisms of endoplasmic reticulum-phagy in neurodegenerative disorders.

关键词： autophagy endoplasmic reticulum endoplasmic reticulum autophagy endoplasmic reticulum quality control system endoplasmic reticulum receptors endoplasmic reticulum-associated degradation neurodegeneration neurodegenerative disease selective autophagy unfolded protein response

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我国股票指数期货若干问题研究

金融理论与实践 2002年第12期 38-40页

作者：孟建国吴鸿雁河南财经学院河南郑州450002 河南省民航管理局河南郑州450003

股票指数期货是一种金融期货合约。它既能够丰富股市交易品种,引进股市双面交易机制,提高资金利用率,又能够规避市场的系统风险和保障宏观经济的平衡运行。股指期货方案的设计必须考虑到我国具体情况,并借鉴其他国家和地区的经验,完善... 详细信息

股票指数期货是一种金融期货合约。它既能够丰富股市交易品种,引进股市双面交易机制,提高资金利用率,又能够规避市场的系统风险和保障宏观经济的平衡运行。股指期货方案的设计必须考虑到我国具体情况,并借鉴其他国家和地区的经验,完善相关的配套措施,以充分吸引套期保值者、投机者和套利者的参与,达到“以流动性创造流动性”的目的。

关键词：股票指数期货框架相关制度中国

Perilipin-2 mediates ferroptosis in oligodendrocyte progenitor cells and myelin injury after ischemic stroke

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Neural Regeneration Research 2025年第7期20卷 2015-2028页

作者： jian Yang jiang wu Xueshun Xie Pengfei Xia Jinxin Lu Jiale Liu Lei Bai Xiang Li Zhengquan Yu Haiying Li Department of Neurosurgery&Brain and Nerve Research Laboratory The First Affiliated Hospital of Soochow UniversitySuzhouJiangsu ProvinceChina Institute of Stroke Research Soochow UniversitySuzhouJiangsu ProvinceChina

Differentiation of oligodendrocyte progenitor cells into mature myelin-forming oligodendrocytes contributes to *** of remyelination due to oligodendrocyte progenitor cell death can result in severe nerve *** is an iron-dependent form of regulated cell death caused by membrane rupture induced by lipid peroxidation,and plays an important role in the pathological process of ischemic ***,there are few studies on oligodendrocyte progenitor cell *** analyzed transcriptome sequencing data from GEO databases and identified a role of ferroptosis in oligodendrocyte progenitor cell death and myelin injury after cerebral *** analysis suggested that perilipin-2(PLIN2)was involved in oligodendrocyte progenitor cell ***2 is a lipid storage protein and a marker of hypoxia-sensitive lipid droplet *** further investigation,we established a mouse model of cerebral ischemia/*** found significant myelin damage after cerebral ischemia,as well as oligodendrocyte progenitor cell death and increased lipid peroxidation levels around the infarct *** ferroptosis inhibitor,ferrostatin-1,rescued oligodendrocyte progenitor cell death and subsequent myelin *** also found increased PLIN2 levels in the peri-infarct area that co-localized with oligodendrocyte progenitor ***2 knockdown rescued demyelination and improved neurological *** findings suggest that targeting PLIN2 to regulate oligodendrocyte progenitor cell ferroptosis may be a potential therapeutic strategy for rescuing myelin damage after cerebral ischemia.

关键词： bioinformatics bulk RNA sequencing ferroptosis ischemic stroke myelin injury oligodendrocyte progenitor cell perilipin-2 single-cell RNA sequencing