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斜加劲梁柱节点翘曲传递分析

浙江大学学报（工学版） 2006年第1期40卷 85-91页

作者：颜潇潇童根树张磊浙江大学土木工程学系浙江杭州310027

对梁和柱内的翘曲位移及其双力矩通过斜加劲的梁柱节点的传递提出了新的数学分析模型.新模型除了节点区内梁柱翼缘在自身平面内的弯曲变形和扭转变形外,还考虑了斜加劲肋在自身平面内的弯曲变形和扭转变形、节点区腹板对斜加劲肋扭转变... 详细信息

对梁和柱内的翘曲位移及其双力矩通过斜加劲的梁柱节点的传递提出了新的数学分析模型.新模型除了节点区内梁柱翼缘在自身平面内的弯曲变形和扭转变形外,还考虑了斜加劲肋在自身平面内的弯曲变形和扭转变形、节点区腹板对斜加劲肋扭转变形的约束,得到了节点域双力矩的计算公式.算例表明,提出的模型与板壳有限元方法结果符合非常好,而传统的梁柱翘曲连续的处理方法与板壳有限元方法结果有较大的误差.该方法可以简单地通过修改传统的薄壁杆件单元刚度矩阵来实现,并可以解决薄壁构件框架弯扭线性和非线性分析.

关键词：翘曲梁柱连接约束扭转弯扭分析

Abnormality of chromosome 8 in desmoid-type fibromatosis

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Chinese Medical Journal 2007年第9期120卷 838-840页

作者： yanG Ji-long WANG Jian ZHOU xiao-yan LI xiao-qiu ZHU Xiong-zeng Department of Pathology Cancer Hospital Fudan University Shanghai 200032 China

Desmoid-type fibromatoses are clonal fibroblastic proliferations that arise in deep soft tissues and are characterized by infiltrative growth and a tendency toward local recurrence. The molecular genetic studies show that there are chromosomal abnormalities relating to the pathogenesis of this lesion, such as trisomy 8. However, there are different results concerning this type of abnormality. Fluorescence in situ hybridization （FISH） is a sensitive and reproducible technique that combines molecular cytogenetics with morphologic information and brings them together in a single frame for evaluation. To explore the controversy of the aneuploid abnormality of chromosome 8, we collected specimens of desmoid-type fibromatosis to determine whether the existence of trisomy 8 chromosome abnormalities correlates with clinicopathologic features, as well as to investigate the feasibility of detecting trisomy 8 in FFPE tissue by FISH method.

关键词： desmoid-type fibromatosis fluorescence in situ hybridization trisomy 8

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水溶性离子液体对甲苯的吸收效果及影响因素

环境工程学报 2017年第3期11卷 1683-1690页

作者：张乐肖潇晏波肖贤明中国科学院广州地球化学研究所有机地球化学国家重点实验室与广东省环境资源利用与保护重点实验室广州510640 中国科学院大学北京100049

选择3种水溶性离子液体(十二烷基咪唑氯盐(DDMIM Cl)、十二烷基咪唑硝酸盐(DDMIM NO_3)、十二烷基咪唑双氰胺盐(DDMIM DCA))作为研究对象寸模拟曱苯废气进行吸收实验,研究了吸收液的吸收性能、甲苯浓度、吸收液浓度、进气气速以及盐度... 详细信息

选择3种水溶性离子液体(十二烷基咪唑氯盐(DDMIM Cl)、十二烷基咪唑硝酸盐(DDMIM NO_3)、十二烷基咪唑双氰胺盐(DDMIM DCA))作为研究对象寸模拟曱苯废气进行吸收实验,研究了吸收液的吸收性能、甲苯浓度、吸收液浓度、进气气速以及盐度等因素对吸收效果的影响以及加热蒸馏法对吸收液的再生与甲苯回收的可行性。结果表明:不同的离子液体对甲苯的吸收率不同J)DMIM DCA的吸收效果最好在质量分数为5%时,初始吸收率达到98%,饱和吸收量为53.39 mg·L^(-1),而DDMIM CKDDMIM NO_3对甲苯的初始吸收率在92%左右,饱和吸收量分别为33.60,37.01 mg·L^(-1);甲苯饱和吸收量与吸收液浓度、甲苯进气浓度呈正相关,与进气气速、含盐度呈负相关;传质系数与甲苯进气浓度、进气气速以及含盐度呈正相关,与吸收液浓度呈负相关;采用加热蒸馏法进行甲苯回收及吸收液再利用时用苯的回收效率达到85%~90%且甲苯的饱和吸收量随着重复利用次数的增加而基本保持不变。因此利用离子液体溶液处理甲苯废气理论上是可行的。

关键词：离子液体甲苯废气蒸馏再生回收

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基于学习不变特征变换的兵马俑图像分区匹配

光学精密工程 2018年第7期26卷 1774-1783页

作者：冯筠延瑜瑜赵妍肖方刘晓宁西北大学信息科学与技术学院陕西西安710127

针对兵马俑图像三维重建时特征误匹配率较高、效率较低的问题,提出了一种基于两视图兵马俑图像的特征分区匹配方案。该方案在兵马俑图像上,首先利用学习不变特征变换(Learned Invariant Feature Transform,LIFT)方法提取整幅兵马俑图像... 详细信息

针对兵马俑图像三维重建时特征误匹配率较高、效率较低的问题,提出了一种基于两视图兵马俑图像的特征分区匹配方案。该方案在兵马俑图像上,首先利用学习不变特征变换(Learned Invariant Feature Transform,LIFT)方法提取整幅兵马俑图像的特征;接着利用提出的基于先验知识的特征点分布曲线分割方法确定兵马俑头部分割线位置,根据头部分割线将提取的特征分为头部特征和躯干特征;最终采用欧式距离进行分区特征匹配,对于匹配结果集合使用随机抽样一致性算法(Random Sample Consensus,RANSAC)滤除误匹配点集。实验结果表明:在兵马俑图像特征提取及匹配中该方案的正确匹配率可以达到98%,相比于SIFT和SURF方法正确匹配率提高了20%左右,特征点的可重复率提高了10%左右,同时将RANSAC的迭代时间降低了50%,而且在尺度、光照、角度发生变换时具有较好的鲁棒性。因此本文提出的方案能够很好地实现特征点的正确匹配,在兵马俑的三维重建中具有很高的使用价值。

关键词：兵马俑特征提取特征匹配 LIFT RANSAC

miRNA-21-5p is an important contributor to the promotion of injured peripheral nerve regeneration using hypoxia-pretreated bone marrow-derived neural crest cells

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Neural Regeneration Research 2025年第1期20卷 277-290页

作者： Meng Cong Jing-Jing Hu yan Yu xiao-Li Li xiao-Ting Sun Li-Ting Wang Xia Wu Ling-Jie Zhu xiao-Jia yang Qian-Ru He Fei Ding Hai-yan Shi School of Medicine Nantong UniversityNantongJiangsu ProvinceChina Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education and Coinnovation Center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina Department of Physiology Jiangsu Health Vocational CollegeNanjingJiangsu ProvinceChina Department of Pathology Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina

Our previous study found that rat bone marrow–derived neural crest cells(acting as Schwann cell progenitors)have the potential to promote long-distance nerve ***-based therapy can enhance peripheral nerve repair and regeneration through paracrine bioactive factors and intercellular ***,the complex contributions of various types of soluble cytokines and extracellular vesicle cargos to the secretome remain *** investigate the role of the secretome and extracellular vesicles in repairing damaged peripheral nerves,we collected conditioned culture medium from hypoxia-pretreated neural crest cells,and found that it significantly promoted the repair of sensory neurons damaged by oxygen-glucose *** mRNA expression of trophic factors was highly expressed in hypoxia-pretreated neural crest *** performed RNA sequencing and bioinformatics analysis and found that miR-21-5p was enriched in hypoxia-pretreated extracellular vesicles of neural crest ***,to further clarify the role of hypoxia-pretreated neural crest cell extracellular vesicles rich in miR-21-5p in axonal growth and regeneration of sensory neurons,we used a microfluidic axonal dissociation model of sensory neurons in vitro,and found that hypoxia-pretreated neural crest cell extracellular vesicles promoted axonal growth and regeneration of sensory neurons,which was greatly dependent on loaded ***,we constructed a miR-21-5p-loaded neural conduit to repair the sciatic nerve defect in rats and found that the motor and sensory functions of injured rat hind limb,as well as muscle tissue morphology of the hind limbs,were obviously *** findings suggest that hypoxia-pretreated neural crest extracellular vesicles are natural nanoparticles rich in ***-21-5p is one of the main contributors to promoting nerve regeneration by the neural crest cell *** helps to explain the mechanism of action of the secretome and e

关键词： axotomy cell-free therapy conditioned medium extracellular vesicles hypoxic preconditioning microRNA oxygen-glucose deprivation peripheral nerve injury Schwann cell precursors

基于A^2/O处理工艺的生活污水的成组生物毒性评价

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环境科学 2017年第3期38卷 1084-1092页

作者：张秋亚马晓妍王晓昌游猛西安建筑科技大学环境与市政工程学院西安710055

为了更加准确评估城市生活污水的综合生物毒性以及处理工艺对污水毒性的削减状况,本研究通过发光菌急性毒性、遗传毒性、雌激素活性检测方法对A^2/O工艺处理前后污水的毒性进行评价,同时通过斑马鱼暴露实验分析污水和回用水对水生生物... 详细信息

为了更加准确评估城市生活污水的综合生物毒性以及处理工艺对污水毒性的削减状况,本研究通过发光菌急性毒性、遗传毒性、雌激素活性检测方法对A^2/O工艺处理前后污水的毒性进行评价,同时通过斑马鱼暴露实验分析污水和回用水对水生生物内分泌干扰效应的作用模式.结果表明,污水厂进水具有较强的急性毒性、遗传毒性以及雌激素活性,水质较差.经二级生物处理后,上述毒性显著性降低,污水厂出水水质提高.但污水出水雌二醇当量为1.89 ng·L-1,仍可能会对受纳水体的水生生物产生潜在危害.浓缩2.5倍的水样导致雄性斑马鱼肝脏的卵黄原蛋白基因(vtg1)和雌激素受体基因(esr1)的表达水平显著上升,由此可以得出污水可通过干扰目的基因的表达来调控水生生物的内分泌活动.而esr1基因在肝脏的表达被抑制说明污水可能具有抗雌激素作用,同时反映进行生物毒性效应分析时应从多个组织或器官考虑,以获得比较全面的信息.

关键词：发光菌遗传毒性雌激素活性斑马鱼生活污水安全性级别

基于FTIR分析猪场废水有机物分解过程中组成结构变化

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光谱学与光谱分析 2016年第11期36卷 3517-3522页

作者：李磊李忠佩刘明吴萌马晓焉唐晓雪中国科学院南京土壤研究所土壤与农业可持续发展国家重点实验室江苏南京210008 中国科学院大学北京100049

猪场废水排放的环境污染问题日益受到重视,研究废水中有机物的组成结构变化将可为制订合理的污染防治措施提供科学依据。本研究通过设置不同规模化猪场废水的室内培养试验,在培养过程中定期采样,采用抽滤、冷冻干燥等方法获得可溶性有机... 详细信息

猪场废水排放的环境污染问题日益受到重视,研究废水中有机物的组成结构变化将可为制订合理的污染防治措施提供科学依据。本研究通过设置不同规模化猪场废水的室内培养试验,在培养过程中定期采样,采用抽滤、冷冻干燥等方法获得可溶性有机物(DOM)固体样品;运用FTIR光谱仪采集样品的红外谱图,研究废水中DOM组成结构在有机分解过程中的变化。结果表明,不同猪场来源的废水中DOM具有类似的组成结构,且主要由蛋白质、脂质类、腐殖酸、多糖类和酚类等有机物组成。随着培养天数的增加,与脂质类、蛋白质和酚类等相关的官能团含量逐渐降低并趋于稳定,而与腐殖酸和多糖类相关的官能团显著增加直至平稳。与初始样品相比,培养20天后样品中DOM组成结构以腐殖酸和多糖类为主,表明DOM的腐殖化程度有所提高。此外,与纤维素分子内氢键缔合的羟基(OH)相比,纤维素分子间氢键缔合的羟基降解速率相对更快,而以前者对微生物的降解更为敏感。废水中DOM以酚羟基C—O的降解速率更快,随后是芳香族COOH、糖类C—O和酰胺羰基CO,而糖类C—O倾向于优先被微生物所利用。综上所述,废水中不同的DOM组成结构在有机降解过程中的变化存在一定差异。

关键词：规模化猪场废水可溶性有机物组成结构傅里叶红外光谱

Endoplasmic reticulum stress and autophagy in cerebral ischemia/reperfusion injury:PERK as a potential target for intervention

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Neural Regeneration Research 2025年第5期20卷 1455-1466页

作者： Ju Zheng Yixin Li Ting Zhang yanlin Fu Peiyan Long xiao Gao Zhengwei Wang Zhizhong Guan xiaolan Qi Wei Hong yan xiao Key Laboratory of Endemic and Ethnic Diseases Ministry of Education&Key Laboratory of Medical Molecular Biology of Guizhou ProvinceGuizhou Medical UniversityGuiyangGuizhou ProvinceChina Guizhou Center for Disease Control and Prevention GuiyangGuizhou ProvinceChina Department of Histology and Embryology Guizhou Medical UniversityGuiyangGuizhou ProvinceChina Collaborative Innovation Center for Prevention and Control of Endemic and Ethnic Regional Diseases Co-constructed by the Province and Ministry GuiyangGuizhou ProvinceChina

Several studies have shown that activation of unfolded protein response and endoplasmic reticulum(ER)stress plays a crucial role in severe cerebral ischemia/reperfusion *** occurs within hours after cerebral ischemia,but the relationship between ER stress and autophagy remains *** this study,we established experimental models using oxygen-glucose deprivation/reoxygenation in PC12 cells and primary neurons to simulate cerebral ischemia/reperfusion *** found that prolongation of oxygen-glucose deprivation activated the ER stress pathway protein kinase-like endoplasmic reticulum kinase(PERK)/eukaryotic translation initiation factor 2 subunit alpha(e IF2α)-activating transcription factor 4(ATF4)-C/EBP homologous protein(CHOP),increased neuronal apoptosis,and induced ***,inhibition of ER stress using inhibitors or by si RNA knockdown of the PERK gene significantly attenuated excessive autophagy and neuronal apoptosis,indicating an interaction between autophagy and ER stress and suggesting PERK as an essential target for regulating *** autophagy with chloroquine exacerbated ER stress-induced apoptosis,indicating that normal levels of autophagy play a protective role in neuronal injury following cerebral ischemia/reperfusion *** from this study indicate that cerebral ischemia/reperfusion injury can trigger neuronal ER stress and promote autophagy,and suggest that PERK is a possible target for inhibiting excessive autophagy in cerebral ischemia/reperfusion injury.

关键词： apoptosis ATF4 autophagy C/EBP homologous protein cerebral ischemia/reperfusion injury eIF2α endoplasmic reticulum stress PERK

Use of a standardized cell culture assay to assess activities of Composite Artemisa Capillaris Tablet against hepatitis B virus replication in vitro

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Use of a standardized cell culture assay to assess activitie...