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腹壁硬纤维瘤诊疗进展

中国实用外科杂志 2024年第3期44卷 349-355页

作者：刘柏岐黄耿文中南大学湘雅医院普外科疝和腹壁外科中心湖南长沙410008

腹壁硬纤维瘤(DT)是一类发生在腹壁肌层的侵袭性纤维瘤,其发病率较低,临床了解较少。该肿瘤具有局部浸润和复发率高的特点,且病程难以预测。目前对于该疾病的诊断和治疗的认识正在不断完善和加深,治疗策略正不断优化。常用影像学诊断方... 详细信息

腹壁硬纤维瘤(DT)是一类发生在腹壁肌层的侵袭性纤维瘤,其发病率较低,临床了解较少。该肿瘤具有局部浸润和复发率高的特点,且病程难以预测。目前对于该疾病的诊断和治疗的认识正在不断完善和加深,治疗策略正不断优化。常用影像学诊断方式包括超声、CT和MRI等。DT的影像学表现具有一定特点,需要与炎性病变或软组织恶性肿瘤相鉴别,最终诊断需要通过活检及组织病理学进行确认。主动监测(AS)作为目前一线治疗策略,对于生长缓慢、无症状或手术风险高的病人,提供了一种避免过度治疗的有效途径。对于需要治疗干预的腹壁DT,首选手术治疗。对于术后切缘阳性或不能手术的腹壁DT,可选择药物治疗或放疗疗法。此外,所有腹壁DT病人应由肉瘤多学科团队进行全面评估和处理,并进行定期的随访和影像学检查,评估治疗效果和复发情况,根据需要调整治疗方案。对于妊娠期DT病人,AS仍为首选治疗方法。对于进展较快的DT病人,孕期积极手术治疗是安全和有效的。但抗肿瘤药物可能会导致卵巢功能障碍相关等不良事件,进而影响育龄女性的生育能力。因此,应在治疗前充分了解可能的生育风险,并考虑向生殖门诊进行咨询。尽管近年来对DT的理解有所进步,但对腹壁DT的诊疗仍无统一标准,需根据个体情况定制治疗计划。

关键词：腹壁硬纤维瘤主动监测靶向药物

基于绩效管理导向的在线学习监测预警体系框架构建研究

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科学决策 2024年第1期 143-153页

作者：张峻赫周启柏宋娟中国系统工程学会社会经济系统工程专业委员会北京开放大学纪委北京邮电大学经济管理学院党委

本文基于绩效管理理论视角,探索性构建在线学习绩效监测预警体系框架,并且进行案例应用研究。研究结果表明,应该基于学习行为、学习满意度和学习结果三个维度内容要素进行在线学习绩效监测预警体系框架的设计构建;以非线性门限回归模型... 详细信息

本文基于绩效管理理论视角,探索性构建在线学习绩效监测预警体系框架,并且进行案例应用研究。研究结果表明,应该基于学习行为、学习满意度和学习结果三个维度内容要素进行在线学习绩效监测预警体系框架的设计构建;以非线性门限回归模型作为“信息处理中枢”,能够提高在线学习绩效监测预警体系框架的有效性;应用所构建的在线学习绩效监测预警体系框架可以实现对在线学习绩效的“绩效管理导向”式量化度量和全景展现,为在线学习资源配置与优化提供不同角度的决策支持科学依据。因此,需要以充分发挥在线学习环境的大数据资源优势,以及门限回归模型等非线性模型在大数据环境中的功效优势为双轮支撑,持续强化对在线学习绩效监测预警体系框架的理论研究与实践应用。

关键词：在线学习绩效管理监测预警体系框架

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亲水性CIT-NaYF_(4)∶Yb^(3+),Ho^(3+)纳米粒子的制备及其发光性能研究

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现代化工 2024年第9期44卷 119-124,131页

作者：白安琪彭孔浩宿欣瑶其布尔李淑荣孟佩俊内蒙古科技大学包头医学院公共卫生学院内蒙古包头014040 内蒙古自治区卫生检测与评价工程技术中心内蒙古包头014040

采用溶剂热法制备了油溶性稀土掺杂上转换纳米粒子NaYF_(4)∶Yb^(3+),Ho^(3+),并利用TEM、XRD、IR、荧光光谱法等考察了反应温度、反应时间、掺杂比等反应条件对纳米粒子形貌、结构、发光性能的影响。结果表明,在反应温度为300℃、反应... 详细信息

采用溶剂热法制备了油溶性稀土掺杂上转换纳米粒子NaYF_(4)∶Yb^(3+),Ho^(3+),并利用TEM、XRD、IR、荧光光谱法等考察了反应温度、反应时间、掺杂比等反应条件对纳米粒子形貌、结构、发光性能的影响。结果表明,在反应温度为300℃、反应时间为50 min、稀土离子掺杂比为NaYF_(4)∶20%Yb^(3+),2%Ho^(3+)条件下,制备出的油溶性NaYF_(4)∶Yb^(3+),Ho^(3+)纳米粒子呈标准六方晶型,尺寸均一、单分散性好,平均粒径为31.55 nm。通过表面配体交换法成功将柠檬酸修饰在其表面,转为亲水性CIT-NaYF_(4)∶Yb^(3+),Ho^(3+)纳米粒子。

关键词： NaYF_(4)∶Yb^(3+) Ho^(3+) CIT-NaYF_(4)∶Yb^(3+) Ho^(3+) 配体交换法柠檬酸

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谷神星一号运载火箭的时变模态参数辨识

振动工程学报 2024年第5期37卷 729-736页

作者：马志赛丁千刘百奇刘建设张军锋董威利天津大学机械工程学院天津300350 天津市非线性动力学与控制重点实验室天津300350 北京星河动力装备科技有限公司北京100176

针对运载火箭这一大型复杂系统,单纯依靠机理分析难以建立能够精确描述其时变特征的动力学模型,借助模态辨识技术获取其在飞行状态下的时变动力学特性尤为必要。面向运载火箭的飞行模态辨识需求,发展基于时变自回归滑动平均模型的仅输... 详细信息

针对运载火箭这一大型复杂系统,单纯依靠机理分析难以建立能够精确描述其时变特征的动力学模型,借助模态辨识技术获取其在飞行状态下的时变动力学特性尤为必要。面向运载火箭的飞行模态辨识需求,发展基于时变自回归滑动平均模型的仅输出递推辨识方法,引入指数加权遗忘机制进行时变特性跟踪,能够在激励未知的情况下仅基于响应数据准确快速辨识运载火箭的时变模态。以谷神星一号运载火箭为例,开展飞行遥测数据的快速处理,准确辨识发射准备阶段和飞行阶段的关键低阶时变模态,辨识结果与有限元分析结果的变化规律相互吻合,验证了所提时变模态仅输出递推辨识方法是有效可行的,服务了运载火箭有限元模型修正和姿控系统设计的实际工程需求。

关键词：运载火箭时变模态参数谷神星一号递推辨识

Em Algorithm of the Truncated Multinormal Distribution with Linear Restriction on the Variables

同方期刊数据库博看期刊评论

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Acta Mathematicae Applicatae Sinica 2018年第1期34卷 155-162页

作者： bai-suo JIN Jing-jing HAN Shu DING bai-qi MIAO Department of Statistics and Finance University of Science and Technology of China Hefei 230026 China Nanjing Research Institute of Electronics Technology Nanjing 210039 China School of Economics Hefei University of Technology Hefei 230009 China

A new expectation-maximization（EM） algorithm is proposed to estimate the parameters of the truncated multinormal distribution with linear restriction on the variables. Compared with the generalized method of moments（GMM） estimation and the maximum likelihood estimation（MLE） for the truncated multivariate normal distribution, the EM algorithm features in fast calculation and high accuracy which are shown in the simulation results. For the real data of the national college entrance exams（NCEE）, we estimate the distribution of the NCEE examinees＇ scores in Anhui, 2003, who were admitted to the university of science and technology of China（USTC）. Based on our analysis, we have also given the ratio truncated by the NCEE admission line of USTC in Anhui, 2003.

关键词： EM algorithm truncated multinormal distribution linear restriction national college entrance exams

Memory devices based on organic electric bistable materials

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Chinese Science Bulletin 2007年第15期52卷 2017-2023页

作者： CHEN qi bai Hua SHI GaoQuant Department of Chemistry Tsinghua University Beijing 100084 China

Organic/metallic composites have demonstrated electrical bistability,as well as memory effects. These advanced materials have shown potential applications in digital information storage because of their good stability,flexibility and fast response speed. The electric bistability phenomenon can be explained by electric field-induced electron transfer/storage. This article reviews the recent progress of memory devices based on organic/metallic and polymeric composites with electric bistability.

关键词：共轭高分子材料数据存储稳定性记忆装置

Nonparametric estimation for contamination distribution

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Applied Mathematics(A Journal of Chinese Universities) 2008年第2期23卷 175-182页

作者： HUI Jun MIAO bai-qi NING Jing PENG Heng Dept. of Statist. and Finance Univ. of Sci. and Tech. of China Hefei 230026 China Dept. of Math. Hefei Univ. of Tech. Hefei 230009 China

In the paper, for the contamination distribution model F（x） = （1-α）F1（x）＋αF2（x）, the estimates of α and F1 （x） are studied using two different ways when F2 （x） is known and the strong consistency of th... 详细信息

关键词： contamination distribution strong consistency rate of consistency.

The application of spectral distribution of product of two random matrices in the factor analysis

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Science China Mathematics 2007年第9期50卷 1303-1315页

作者： bai-suo JIN bai-qi MIAO Wu-yi YE Zhen-xiang WU Department of Statistics and Finance University of Science and Technology of ChinaHefei 230026China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100080China

In the factor analysis model with large cross-section and time-series dimensions,we pro- pose a new method to estimate the number of *** if the idiosyncratic terms satisfy a linear time series model,the estimators of the parameters can be obtained in the time series model. The theoretical properties of the estimators are also explored.A simulation study and an empirical analysis are conducted.

关键词： limiting spectral distribution product of random matrices large dimensional random matrices factor number time series 60F15 62H99

Genome-wide identification, characterization and evolution of cuticular protein genes in the malaria vector Anopheles sinensis （Diptera： Culicidae）

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Insect Science 2018年第5期25卷 739-750页

作者： bai-qi Liu Liang qiao qi-Yi He Yong Zhou Shuang Ren Bin Chen Chongqing Key Laboratory of Vector Insects Institute of Entomology and Molecular Biology Chongqing Normal University Chongqing China

Thirteen cuticular protein （CP） families have been recognized in arthropods. In this study, 250 Anopheles sinensis CP genes were identified and named based on genome and transcriptome sequences. They were classified into 10 families based on mo- tifs and phylogenetic analyses. In 11 other insect species, nine had CP numbers 〉 150 while Apis mellifera and Tribolium castaneum had CP numbers less than 52. The CPs of eight species occupied 〉 1.4% of the total genomic gene number, whereas in three species the CPs occupied 〈 1%. The phylogenies for each CP family in An. sinensis were constructed and discussed. The 250 CPs each had 1-8 exons with 144 CPs （57.6%） having two exons. The intron length ranged from 66--3888 bp with 174 introns （54.0%） being 66--100 bp long. Except for two CPs on two contigs, 248 CPs were mapped onto 28 scaffolds with 136 genes （54.4%） restricted to five scaffolds. A total of 107 CPs were clustered and located at 27 loci. The CPR family had the conserved motif GSYS- LVEPDGTVRTV. The RR- 1 subfamily had an additional 21 amino acid （aa） motifs with the YVADENGF sequence that is common in insects. The RR-2 subfamily had an additional 50 aa motifs with two additional regions RDGDWKG and G-x（3）-VV. A comparison with 115 orthologous counterparts of An. gambiae CPs suggested purifying selection for all of these genes. This study provides basic information useful for further studies on biological functions of An. sinensis CPs as well as for comparative genomics of insect CPs.

关键词： Anopheles sinensis characterization cuticular protein genes genome-wideidentification phylogenetics Ka/Ks