检索结果-南通市图书馆

Chinese Medical Sciences Journal 2021年第1期36卷 66-71页

作者： Dasheng Li dawei Wang Nana Wang Haiwang Xu He Huang Jianping Dong Chen xia Department of Radiology Beijing Haidian Section of Peking University Third Hospital(Beijing Haidian Hospital)Beijing 100080China Institute of Advanced Research Infervision Medical Technology Co.Ltd.Beijing 100025China Department of Infection Beijing Haidian Section of Peking University Third Hospital(Beijing Haidian Hospital)Beijing 100080China

In the era of coronavirus disease 2019(COVID-19)pandemic,imported COVID-19 cases pose great challenges to many *** CT examination is considered to be complementary to nucleic acid test for COVID-19 detection and *** report the first community infected COVID-19 patient by an imported case in Beijing,which manifested as nodular lesions on chest CT imaging at the early *** Learning(DL)-based diagnostic systems quantitatively monitored the progress of pulmonary lesions in 6 days and timely made alert for suspected pneumonia,so that prompt medical isolation was *** patient was confirmed as COVID-19 case after nucleic acid test,for which the community transmission was prevented *** roles of DL-assisted diagnosis in helping radiologists screening suspected COVID cases were discussed.

关键词： coronavirus disease 2019 imported cases computed tomography deep learning diagnosis

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社交媒体投资者行为、行业波动与溢出效应

科研管理 2023年第5期44卷 174-183页

作者：金大卫陈镜宇夏梦冉中南财经政法大学信息与安全工程学院湖北武汉430073 中南财经政法大学统计与数学学院湖北武汉430073

我国股市频繁出现各行业股票同涨同跌和轮动异象,社交媒体中活跃的投资者行为可能加速、加剧行业间的风险传染。因此,厘清社交媒体中的投资者行为对股市行业风险的影响及其传导性是防控股市行业风险传染的基本前提。本文以2019—2020年... 详细信息

我国股市频繁出现各行业股票同涨同跌和轮动异象,社交媒体中活跃的投资者行为可能加速、加剧行业间的风险传染。因此,厘清社交媒体中的投资者行为对股市行业风险的影响及其传导性是防控股市行业风险传染的基本前提。本文以2019—2020年我国A股19个行业下的153家上市公司为样本,在行业层面实证检验了社交媒体中投资者情绪和投资者关注对已实现波动率的影响,探究了行业情绪溢出效应的存在性及其传播路径,并进一步讨论了新冠疫情后的溢出情况。研究结果表明:投资者情绪及关注的高涨和投资者意见分歧的扩大化均会显著加剧行业波动;而投资者情绪及关注的大幅变动,则会抑制行业波动。整体来看,市场中存在经由投资者行为的行业间风险传染现象,投资者情绪溢出效应的理论假说被证实,具体表现为7对显著的情绪溢出关系,且溢出方向单一明确。后疫情时代,存在情绪溢出关系的行业降为5对,并表现出溢出强度变大、影响范围缩小且存在连续路径的新特征。本文揭示了相对隐蔽的跨行业情绪溢出路径,扩展了投资者行为溢出的研究内容,对后疫情时代下市场高度不确定情境中的金融实践具有重要现实启示。

关键词：社交媒体投资者行为行业波动溢出效应金融实践

Synergistic effects of ginseng stem and leaf-extracted ginsenoside and choline on improving learning and memory in rats Association verification experiment in animals with multiple learning and memory disorders

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Neural Regeneration Research 2008年第2期3卷 187-191页

作者： xiaomin Zhao Hongxia GU Qing Li xianglin Xie Zuoli xia Hongxin Cai Ling Zhang dawei Li Xinnong Wang Department of Pharmacology Taishan Medical College Taian 271000 Shandong Province China Department of Brain Microcirculation Taishan Medical College Taian 271000 Shandong Province China Life Science Institute Taishan Medical College Taian 271000 Shandong Province China Department of Kidney Medicine the 88 HosPital of Chinese PLA Taian 271000 Shandong Province China Department of Pharmacy Central Hospital of Taian Taian 271000 Shandong Province China Department of Pharmacology Normal Bethune Medical College Jilin University Changchun 130021 Jilin Province China

BACKGROUND： Ginsenoside extracted from the stem and leaf of ginseng （GSL） and choline have both been shown to improve learning and memory functions; however, further studies are needed to understand the synergistic effects of a combination of both. OBJECTIVE： To verify the combined improved synergistic effects of GSL and choline on learning and memory disorders in rats. DESIGN： Control observation. SETTING： Taishan Medical College. MATERIALS： A total of 150 male Kunming mice weighing （204-2） g and 40 healthy male Wistar rats weighing （2204-20） g were provided by the Experimental Animal Department of Jilin University. Animal experimentation received confirmed consent from the local ethic committee. GSL was provided by the Department of Chemistry, Norman Bethune Medical University, and choline was provided by the Third Experiment Factory, Shanghai. METHODS： This study was performed at the Life Science Institute, Taishan Medical College from October 2006 to February 2007. ① Scopolamine-induced learning and memory disorders in rats： Forty rats were randomly divided into control group, model group, combination group （400 mg/kg GSL ＋ 200 mg/kg choline）, GSL （400 mg/kg） group, and choline （200 mg/kg） group, 8 rats/group. Rats were perfused and administrated in the morning, once a day for 14 successive days. Rats in the control group and model group were perfused with 20 mL/kg distilled water and underwent Morris water maze spatial resolution test 1 hour after perfusion on the 10m, 11m, and 12m days after administration. Rats also underwent passive step-down avoidance test 1 hour after reperfusion on the 13m and 14m days after administration. Thirty minutes prior to experimentation, rats in the remaining three groups were intraperitoneally （i.p） injected with 2 mg/kg scopolamine, and rats in the control group were i.p. injected with 2 mL/kg saline. ② Scopolamine-induced learning disorder and memory acquired disorder in mice： Fifty mice were randomly divided into contr

关键词： ginsenoside of stem and leaf choline learning memory

Sleep Deprivation Selectively Down-Regulates Astrocytic 5-HT2B Receptors and Triggers Depressive-Like Behaviors via Stimulating P2X7 Receptors in Mice

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Neuroscience Bulletin 2020年第11期36卷 1259-1270页

作者： Maosheng xia Zexiong Li Shuai Li Shanshan Liang xiaowei Li Beina Chen Manman Zhang Chengyi Dong Alexei Verkhratsky dawei Guan Baoman Li Practical Teaching Centre School of Forensic MedicineChina Medical UniversityShenyang 110122China Department of Orthopaedics The First HospitalChina Medical UniversityShenyang 110001China Faculty of Biology Medicine and HealthThe University of ManchesterManchester M139PLUK Department of Forensic Pathology School of Forensic MedicineChina Medical UniversityShenyang 110122China Department of Poison Analysis School of Forensic MedicineChina Medical UniversityShenyang 110122China

Chronic loss of sleep damages health and disturbs the quality of ***-lasting sleep deprivation(SD)as well as sleep abnormalities are substantial risk factors for major depressive disorder,although the underlying mechanisms are not ***,we showed that chronic SD in mice promotes a gradual elevation of extracellular ATP,which activates astroglial P2X7 receptors(P2X7Rs).Activated P2X7Rs,in turn,selectively down-regulated the expression of 5-HT2B receptors(5-HT2BRs)in *** of P2X7Rs induced by SD selectively suppressed the phosphorylation of AKT and FoxO3 a in astrocytes,but not in *** overexpression of FoxO3a in astrocytes inhibited the expression of ***-regulation of 5-HT2BsRs instigated by SD suppressed the activation of STAT3 and relieved the inhibition of Ca2+-dependent phospholipase *** latter cascade promoted the release of arachidonic acid and prostaglandin *** depression-like behaviors induced by SD were alleviated in P2X7R-KO *** study reveals the mechanism underlying chronic SD-induced depression-like behaviors and suggests 5-HT2BRs as a key target for exploring therapeutic strategies aimed at the depression evoked by sleep disorders.

关键词： Astrocyte Sleep deprivation P2X7 receptor 5-HT2B receptor FoxO3a

Association of serum lipids and severity of epithelial ovarian cancer：an observational cohort study of 349 Chinese patients

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The Journal of Biomedical Research 2018年第5期32卷 336-342页

作者： Yi Zhang Jing Wu Junya Liang Xing Huang Lei xia dawei Ma Xinyu Xu Pingping Wu Department of Pathology Jiangsu Institute of Cancer Research the Affiliated Cancer Hospital of Nanjing Medical University Nanjing Jiangsu 210009 China Department of Radiation Oncology Jiangsu Cancer Hospital Jiangsu Institute of Cancer Research the Affiliated Cancer Hospital of Nanjing Medical University Nanjing Jiangsu 210009 China The School of Public Health Nanjing Medical University Nanjing Jiangsu 211166 China Department of Oncology Jiangsu Cancer Hospital Jiangsu Institute of Cancer Research the Affiliated Cancer Hospital of Nanjing Medical University Nanjing Jiangsu 210009 China.

While obesity and fat intake have been associated with the risk and prognosis of epithelial ovarian cancer, the association between the lipid levels and epithelial ovarian cancer phenotype remains controversial. We conducted a retrospective study of 349 epithelial ovarian cancer patients who received treatment at Jiangsu Cancer Hospital, China between 2011 and 2017. We analyzed age at diagnosis, blood pressure, plasma glucose content, body mass index（BMI）, lipid levels and clinical parameters. Severity of epithelial ovarian cancer was classified according to the International Federation of Gynecology and Obstetrics（FIGO） grading system. Univariate analysis of the clinical factors according to the severity of epithelial ovarian cancer was followed by logistic regression analysis to identify clinical factors significantly associated with epithelial ovarian cancer severity. Univariate analysis indicated that age,BMI, triglyceride（TG）, and high density lipoproteins（HDL） differed significantly among different stages of epithelial ovarian cancer（P〈0.05）. In the logistic regression model, elevated TG（OR： 1.883; 95% CI= 1.207-2.937）, and low HDL（OR： 0.497; 95% CI = 0.298-0.829） levels were significantly associated with the high severity epithelial ovarian cancer. Our data indicate that high TG and low HDL levels correlate with a high severity of epithelial ovarian cancer. These data provide important insight into the potential relationship between the lipid pathway and epithelial ovarian cancer phenotype and development.

关键词： triglycerides epithelial ovarian cancer high density lipoproteins dyslipidemia clinical data statistics

从《建筑碳排放计算标准》看北京冬奥会场馆的低碳设计策略

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南方建筑 2023年第5期2卷 11-18页

作者：夏叶肖大威陶立克华南理工大学建筑学院、亚热带建筑科学国家重点实验室

《建筑碳排放计算标准》是北京冬奥会场馆碳排放量核算依据,为了通过技术性引导来激发建筑师的创造力,结合实际运用来解读标准中所包含的设计策略。基于标准所构建的框架,从建材生产运输、建造及拆除、建筑运行三个阶段来总结冬奥场馆... 详细信息

《建筑碳排放计算标准》是北京冬奥会场馆碳排放量核算依据,为了通过技术性引导来激发建筑师的创造力,结合实际运用来解读标准中所包含的设计策略。基于标准所构建的框架,从建材生产运输、建造及拆除、建筑运行三个阶段来总结冬奥场馆的低碳设计策略。建材生产运输阶段可通过数字化软件,选用低碳排放系数建材和当地材料,以及钢结构的轻量化来降低碳排放;建造拆除阶段可通过减少土方量,采用预制装配式技术和既有建筑改造等策略降低碳排放;建筑运行阶段可通过引入自然通风、自然采光,使用可再生能源,增加绿地碳汇等策略降低碳排放。

关键词：建筑碳排放标准冬奥场馆低碳设计策略

同方期刊数据库博看期刊评论

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面向性能分析的枪械数字样机设计与实现

兵器装备工程学报 2022年第2期43卷 72-77,110页

作者：苑大威夏雪蛟李晓寅瞬态冲击技术重点实验室北京102202 中国兵器工业第208研究所北京102202 中国航天科工集团第三研究院创新研究院北京100074 中国兵器工业标准化研究所北京100089

针对枪械传统设计过程中指标验证过度依赖实物试验的问题,提出了枪械数字样机构建方法;根据典型枪械工作特点和性能指标,基于三维模型的几何样机,结合相关仿真分析软件,建立了面向枪械多项功能性能的仿真模型,分析了疲劳寿命、射击精度... 详细信息

针对枪械传统设计过程中指标验证过度依赖实物试验的问题,提出了枪械数字样机构建方法;根据典型枪械工作特点和性能指标,基于三维模型的几何样机,结合相关仿真分析软件,建立了面向枪械多项功能性能的仿真模型,分析了疲劳寿命、射击精度、终点威力、人机工效等内容,得到了具体的参数值;结果表明:枪械数字样机能够从结构合理性、原理可行性、指标可达性、措施有效性4个维度进行仿真分析,在计算机上实现了对物理样机功能和性能的分析和评价,为枪械的结构改进和性能优化提供了数字化手段,能够有效减少样机研制过程中的加工和试验轮次,支撑枪械设计效率和水平的提升。

关键词：枪械数字样机性能样机仿真

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工程项目社会影响评估和社会成本分析

土木工程学报 2022年第1期55卷 117-128页

作者：吴柯娴金伟良沈坚张大伟夏晋浙江大学浙江杭州310058 浙江数智交院科技股份有限公司浙江杭州310013

社会影响是指某种产品或行为,通过改变人群的生活、工作、休闲、社交和组织方式,对个人或公共机构造成的不利影响。工程结构的建造、维护、翻新、修复或拆除往往会在施工期间对周围人群或环境产生影响,尤其是对交通运输或居住环境影响... 详细信息

社会影响是指某种产品或行为,通过改变人群的生活、工作、休闲、社交和组织方式,对个人或公共机构造成的不利影响。工程结构的建造、维护、翻新、修复或拆除往往会在施工期间对周围人群或环境产生影响,尤其是对交通运输或居住环境影响较大的工程项目,其不利社会影响所带来的社会成本可能远大于工程的实际成本。社会影响评估作为可持续性评估领域的三大支柱之一,被越来越多地考虑到工程结构的全寿命设计与管理中。文章首先对社会影响评估的起源和发展进行梳理,明确工程项目的社会影响类别和利益相关者。其次,介绍了两种社会影响评估方法,分别是性能评分法和影响路径法,整理文献中有关性能评分法的社会影响类别和性能参考点,建立基于影响路径法的工程项目社会成本指标体系。随后,按照利益相关者类别划分社会成本指标,重点整理包括生产事故成本、交通事故成本、交通延误成本、区域经济损失、居住环境质量损失和公共福利损失在内的社会成本量化方法。最后针对社会影响识别和成本量化方法中的局限进行讨论,明确工程结构社会影响评估的发展方向。

关键词：工程项目社会影响利益相关者社会影响评估社会成本

Mechanical Behavior of Rectangular Steel-Reinforced ECC/Concrete Composite Column under Eccentric Compression

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Transactions of Tianjin University 2015年第3期21卷 269-277页

作者：潘金龙鲁冰顾大伟夏正昊夏天阳 Key Laboratory of Concrete and Pre-stressed Concrete Structures of Ministry of Education Southeast University

In order to improve the seismic performance, deformation ability and ultimate load-carrying capacity of columns with rectangular cross section, engineered cementitious composite(ECC) is introduced to partially substitute concrete in the edge zone of reinforced concrete columns and form reinforced ECC/concrete composite ***, based on the assumption of plane remaining plane and the simplified constitutive models, the calculation method of the load-carrying capacity of reinforced ECC/concrete columns is proposed. The stress and strain distributions and crack propagation of the composite columns in different states of eccentric compressive loading are analyzed. Then, nonlinear finite element analysis is conducted to study the mechanical performance of reinforced ECC/concrete composite columns with rectangular cross section. It is found that the simulation results are in good agreement with the theoretical results, indicating that the proposed method for calculating the load-carrying capacity of concrete/ECC composite columns is valid. Finally, based on the proposed method, the effects of ECC thickness, compressive strength of concrete and longitudinal reinforcement ratio on the mechanical performance of reinforced ECC/ concrete composite columns are analyzed. Calculation results indicate that increasing the thickness of ECC layer or longitudinal reinforcement ratio can effectively increase the ultimate load-carrying capacity of the composite column with both small and large eccentricity, but increasing the strength of concrete can only increase the ultimate loadcarrying capacity of the composite column with small eccentricity.

关键词：钢筋混凝土柱矩形截面柱偏心受压 ECC 组合柱力学行为极限承载能力水泥复合材料

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一种抗背景干扰的多尺度人群计数算法

计算机工程 2022年第5期48卷 251-257页

作者：郭爱心夏殷锋王大为芦宾山西师范大学物理与信息工程学院太原030006 中国科学技术大学自动化系合肥230026

人群计数技术以估计人群图片或视频中的人数为目标,可以有效预防人群踩踏事故的发生,广泛应用于安防预警、城市规划及大型集会管理等领域。然而,由于人群尺度变化、背景干扰、人群分布不均、遮挡和透视效应等因素的影响,单幅图片的人群... 详细信息

人群计数技术以估计人群图片或视频中的人数为目标,可以有效预防人群踩踏事故的发生,广泛应用于安防预警、城市规划及大型集会管理等领域。然而,由于人群尺度变化、背景干扰、人群分布不均、遮挡和透视效应等因素的影响,单幅图片的人群计数仍是一项非常具有挑战性的任务。针对人群计数中多尺度变化和背景干扰问题,提出一种抗背景干扰的多尺度人群计数算法。以VGG16网络结构为基础,引入特征金字塔构建多尺度特征融合骨干网络解决人群多尺度变化问题,设计Double-Head-CC结构对融合后的特征图进行前景背景分割和密度图预测以抑制背景干扰。基于密度图的局部相关性和多任务学习,定义多重损失函数和多任务联合损失函数进行网络优化。在ShanghaiTech、UCF-QNRF和JHU-CROWD++数据集上进行训练和评测,实验结果表明,该算法能够很好地预测人群密度分布和人群数量,具有较高的准确性,且鲁棒性强、泛化性能良好。

关键词：人群计数深度学习特征金字塔损失函数密度图