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具有群组固定效应的函数型面板分位数回归模型

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数学学报（中文版） 2024年第4期67卷 675-703页

作者：刘华王子剑门嘉齐尤进红西安交通大学经济与金融学院西安710049 上海财经大学统计与管理学院上海200433

面板数据分析和函数型数据分析是统计学和计量经济学等领域中非常热门的研究问题.随着实际应用的复杂化,数据的类型变得越来越多样化.通常数据的同质性和异质性会同时存在,为了进行正确和有效的统计推断,对二者进行识别是非常有必要的,... 详细信息

面板数据分析和函数型数据分析是统计学和计量经济学等领域中非常热门的研究问题.随着实际应用的复杂化,数据的类型变得越来越多样化.通常数据的同质性和异质性会同时存在,为了进行正确和有效的统计推断,对二者进行识别是非常有必要的,因此本文提出一类具有未知群组固定效应的函数型面板分位数回归模型.由于面板数据是时间序列数据与截面数据的综合,函数型数据具有无穷维特征,所以函数型面板数据分位数回归的计算会面临极大的挑战.为了处理此类大样本和高维度数据带来的计算复杂度,本文采用最新提出的卷积方法对目标函数进行光滑化处理,并且结合贝叶斯信息准则和聚合层次聚类算法来识别潜在群组结构.基于识别出的群组结构信息,本文创新性地提出了二元时变系数函数的有效估计,同时,本文证明了群组识别方法的相合性以及相应估计量的渐近正态性.最后,本文通过数值模拟结果与对江西省87个县的居民用电数据和基尼系数的分析,说明模型的合理性以及推断方法的有效性.

关键词：函数型面板数据群组结构固定效应分位数回归聚合层次聚类

A Case of Acute HIV-1 and Monkeypox Coinfection After Condomless Insertive Anal Sex in the Previous 69 Days—Beijing Municipality,China,August-October,2023

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China CDC weekly 2024年第7期6卷 126-130页

作者： Lin jia Han jia Yuan Fang Benyong Yan Mei Zhang Yang Zhang Wen Wang Caiping Guo Xiaojie Huang Tong Zhang Taiyi jiang Clinical and Research Center for Infectious Diseases Beijing Youan HospitalCapital Medical UniversityBeijingChina

Summary What is already known about this topic?The prevalence of monkeypox(mpox)infections is primarily observed among young men who engage in sexual activities with other men,and there is a possibility of sexual ***-occurring sexually transmitted infections have also been *** is added by this report?In this report,we present a case of a patient in China who was simultaneously diagnosed with mpox,and acute human immunodeficiency virus(HIV)infection.

关键词： acute Acute prevalence

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基于智能合约的流数据授权撤销方案研究

计算机科学 2024年第10期51卷 372-379页

作者：门蕊蕊贾洪勇都金如郑州大学网络空间安全学院郑州450000

物联网设备和服务将实时生成的流数据加密后进行外包存储,并通过访问控制对用户进行授权,当用户的身份或权限发生变更时,需要撤销用户的权限。现有撤销方案通常存在密钥频繁更新和重加密密文的问题,导致撤销效率低下,灵活度不足,难以实... 详细信息

物联网设备和服务将实时生成的流数据加密后进行外包存储,并通过访问控制对用户进行授权,当用户的身份或权限发生变更时,需要撤销用户的权限。现有撤销方案通常存在密钥频繁更新和重加密密文的问题,导致撤销效率低下,灵活度不足,难以实现实时撤销,面临数据泄露风险。为解决流数据外包存储场景下的实时授权撤销问题,提出了一种基于智能合约的去中心化授权撤销方案。在边缘计算和区块链相结合的物联网架构下,将流数据按照时间间隔分块,使用HASH树生成与块对应的大量且唯一的密钥,并对分块数据进行对称加密;树节点创建访问令牌并通过代理重加密技术进行共享,实现了可更改的访问策略和高效动态数据共享;利用智能合约技术创建访问控制列表和不当行为列表,对用户权限进行定时撤销和即时撤销操作,实现了去中心化的实时授权撤销。安全性分析和仿真实验证明所提方案与其他相关的研究方案相比,提供了更好的安全性、功能、通信和计算成本,更具有效性。

关键词：流数据边缘计算区块链智能合约访问控制授权撤销

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论全过程人民民主的三重逻辑

黑龙江社会科学 2024年第5期 15-20,144页

作者：李丹门佳琪江苏师范大学马克思主义学院江苏徐州221116

全过程人民民主是彰显中国特色社会主义民主制度优越性的具有开创性的民主模式,对中国特色社会主义民主建设和世界民主政治发展具有重大意义。从历史逻辑看,全过程人民民主是中国共产党和中国人民经历探索与确立、健全与完善、发展与创... 详细信息

全过程人民民主是彰显中国特色社会主义民主制度优越性的具有开创性的民主模式,对中国特色社会主义民主建设和世界民主政治发展具有重大意义。从历史逻辑看,全过程人民民主是中国共产党和中国人民经历探索与确立、健全与完善、发展与创新多阶段曲折实践而诞生的宝贵成果。从理论逻辑看,全过程人民民主一方面传承了中国古代传统民本思想的优良基因,通过赋权于民实现了对其的本质超越;另一方面,与西方民主不同,全过程人民民主实现了对马克思主义民主理论的丰富和创新。从实践逻辑看,全过程人民民主一直以人民至上为宗旨,以党的领导为核心,以真实有效为追求。这三重逻辑之间有着密切的内在联系,从三重逻辑相统一的视角开展研究,将有助于科学把握全过程人民民主的整体内涵。

关键词：全过程人民民主中国共产党马克思主义社会主义民主

PHASE BEHAVIOR OF CHARGE STABLIZED COLLOID DISPERSION WITH ADDED WATER SOLUBLE POLYMERS

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Chinese Journal of Polymer Science 2013年第9期31卷 1218-1224页

作者： jia-xue Liu Yong-feng men State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

Demixing and colloidal crystallization in the mixture of charge stabilized colloidal poly（methyl methacrylate） particles and soluble poly（ethylene oxide） were investigated by means of synchrotron small-angle X-ray scattering （SAXS） technique. Phase diagram of the mixture was obtained based on visual inspection and SAXS results. The phase behavior is determined as a function of the concentration of the polymer as well as the volume fraction of the colloidal particles. The system shows a one phase region when the concentration of the polymer is low, whereas a two-phase region is present when the concentration of the polymer is larger than a critical concentration at certain volume fraction of the colloids. Interestingly, a face centered cubic colloidal crystalline structure was formed under certain conditions, which has been rarely observed in experiments of colloid-polymer mixtures with competing interactions.

关键词： Colloid-polymer mixture Phase behavior Crystallization.

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酿酒酵母转化半乳糖醇的工程菌株构建及优化

生物工程学报 2024年第6期40卷 1909-1923页

作者：邓连妹李娇门燕孙媛霞贾士儒朱玥明天津科技大学生物工程学院天津300457 中国科学院天津工业生物技术研究所工业酶国家重点实验室天津300308

半乳糖醇是一种稀少糖醇,广泛应用于食品工业与医药领域。工业上一般通过化学氢化法生产半乳糖醇,但反应条件苛刻、生产成本高、对环境不友好,亟须开发更有效的“绿色”生物合成技术。本研究挖掘了来源于黑曲霉(Aspergillus niger)CBS 5... 详细信息

半乳糖醇是一种稀少糖醇,广泛应用于食品工业与医药领域。工业上一般通过化学氢化法生产半乳糖醇,但反应条件苛刻、生产成本高、对环境不友好,亟须开发更有效的“绿色”生物合成技术。本研究挖掘了来源于黑曲霉(Aspergillus niger)CBS 513.88的木糖还原酶(Aspergillus niger xylose reductase,AnXR),该酶属于NADPH依赖的醛酮还原酶家族。对AnXR的酶学性质进行研究,发现其最适温度和pH分别为25℃和8.0。以酿酒酵母(Saccharomyces cerevisiae)为底盘细胞,利用基因重组技术敲除半乳糖激酶(galactokinase,GAL1)基因,使得宿主细胞对半乳糖的分解代谢利用大幅降低,并在此底盘菌株中引入AnXR基因构建了催化D-半乳糖生成半乳糖醇的工程菌株。对工程菌株全细胞转化的条件进行优化,半乳糖醇的最高产量达到12.10g/L。同时,该菌株对其他单糖的还原能力也进行了测试,可生成木糖醇、阿拉伯糖醇等功能性糖醇。利用本研究构建的工程菌株可以实现半乳糖醇等多种功能糖醇的高效生物转化,对稀少糖醇的绿色制造具有借鉴意义。

关键词：半乳糖醇木糖还原酶酿酒酵母工程菌株全细胞转化

Success rate of current human-derived gastric cancer organoids establishment and influencing factors:A systematic review and meta-analysis

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1626-1646页

作者： Kai-Lin jiang Xiang-Xiang Wang Xue-jiao Liu Li-Kun Guo Yong-Qi Chen Qing-Ling jia Ke-Ming Yang jiang-Hong Ling Department of Gastroenterology Shuguang HospitalShanghai 200021China Department of Pathology Shuguang HospitalShanghai 200021China

BACKGROUND Human-derived gastric cancer organoids(GCOs)are widely used in gastric cancer research;however,the culture success rate is generally *** To explore the potential influencing factors,and the literature on successful culture rates of GCOs was reviewed using *** PubMed,Web of Science,and EMBASE were searched for *** trained researchers selected the studies and extracted *** 17.0 software was used for meta-analysis of the incidence of each outcome *** adjusted Methodological Index for Non-Randomized Studies scale was used to assess the quality of the included *** plots and Egger’s test were used to detect publication *** analyses were conducted for sex,tissue source,histo-logical classification,and the pathological tumor-node-metastasis(pTNM)cancer staging *** Eight studies with a pooled success rate of 66.6%were *** derived from women and men had success rates of 67%and 46.7%,*** from surgery or biopsy/endoscopic submucosal dissection showed success rates of 70.9%and 53.7%,*** of poorly-differentiated,moderately-differentiated and signet-ring cell cancer showed success rates of 64.6%,31%,and 32.7%,*** with pTNM stages I-II and III-IV showed success rates of 38.3%and 65.2%,respectively.Y-27632 and non-Y-27632 use showed success rates of 58.2%and 70%,*** generated with collagenase were more successful than those constructed with Liberase TH and TrypLE(72.1%vs 71%,respectively).EDTA digestion showed a 50%lower success rate than other methods(P=0.04).CONCLUSION GCO establishment rate is low and varies by sex,tissue source,histological type,and pTNM *** Y-27632,and using Liberase TH,TrypLE,or collagenase yields greater success than EDTA.

关键词： Gastric cancer organoids Human-derived organoids Gastric cancer Cell lines In vitro research models

AlScN films prepared by alloy targets and SAW device characteristics

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Journal of Rare Earths 2023年第3期41卷 434-439,I0004页

作者： Kuo men Hao Liu Xingquan Wang Qian jia Zhaochong Ding Huating Wu Daogao Wu Yuhua Xiong State Key Laboratory of Advanced Materials for Smart Sensing GRINM Group Co.Ltd.Beijing 100088China GRIMAT Engineering Institute Co. Ltd.Beijing 101402China State Key Laboratory of Non-ferrous Metals and Processes GRINM Group Co.Ltd.Beijing 100088China GRIKIN Advanced Material Co.Ltd. Beijing 100220China GRIREM Advanced Materials Co.Ltd. Beijing 100088China

In this paper,we reported a surface acoustic wave(SAW)device prepared and optimized by piezoelectric films containing AIN,AIScN(Sc-20 at%)and AIScN(Sc-30 at%)by reactive magnetron sputtering using Al and AISc alloy *** calculated the material intrinsic electromechanical coupling coefficient k_(t)^(2) of AlScN(Sc-20 at%)and AlScN(Sc-30 at%)which are much better than *** can be explained by the lattice ***,the results were confirmed by transmission electron microscopy(TEM)observation of the *** the SAW devices based on three thin films were tested by vector network analysis obtaining the device equivalent electro mechanical coupling coefficient k_(eff)^(2).The value of AIScN(Sc-20 at%)k_(eff)^(2),which equals to 1.94%,is higher than that of AIN and AIScN(Sc-30 at%)while the value of AIScN(Sc-30 at%)k_(t)^(2) is higher than that of *** is shown in our study that the crystallinity and orientation of the material still have a greater impact on k_(eff)^(2) but it does not have influence on k_(t)^(2) in the actual device preparation process.

关键词： AlScN film Alloy targets SAW Electromechanical coupling coefficient k_(t)^(2) Crystallinity Orientation

Research on A Checking Method of Vibration Characteristics for Test System

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仪器仪表学报 2013年第S1期34卷 165-170页

作者： men Xiu hua Xu jia LiuBaojian Fu Xiuli School ofMechanical Engineering University of Jinan Xi’anAircraftCompany Sa ic-ivecoHongyan Commercia l Vehicle CO.LTD

To ensure the accuracy and precision of vibration test,a universal checking method is *** use of the method is discussed and an actual example is ***,the calibration of the 7703A-500 type sensor is analyzed on the basis of frequency response *** frequency range of normal working can be determined by the exact calibration of sensitivity,frequency response and *** the basic problem of abnormal signals appearing in test system,the method of zero check and loading vibration source are *** frequency spectrum of output signals is employed to distinguish the noise signal,unknown source signal and useful signal ***,the experimental results reveal the importance to improve the accuracy of the results of practical vibration test.

关键词： vibration test sensor calibration signal sensitivity linearity frequency response