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Geochemical characteristics of Holocene sediments from Chuadanga district, Bangladesh: Implications for weathering, climate, redox conditions, provenance and tectonic setting

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Chinese Journal Of Geochemistry 2014年第4期33卷 336-350页

作者： Ismail Hossain Krisna kanta roy Pradip Kumar Biswas Mahbubul Alam Md. Moniruzzaman Farah Deeba Department of Geology and Mining University of Rajshahi Bangladesh Institute of Mining Mineralogy and Metallurgy (IMMM) Joypurhat Bangladesh Water Resource Planning Division Institute of Water Modelling (IWM) Dhaka Bangladesh Institute of Nuclear Science and Technology (INST) Atomic Energy Commission Dhaka Bangladesh

The present research deals with the geochemical characteristics of the Holocene sediments from Alamdanga area, Chuadanga district, Bangladesh. Main goals of the study are to delineate source rock characteristics, degree of chemical weathering and sorting processes and behavior of redox conditions during deposition of the sediments. Geochemical characteristics of the sediments show comparatively a wide variation in accordance with stratigraphy in their major element contents(e.g. Si O2 69.46–82.13, Al2O3 2.28–8.88 in wt%), reflecting the distinctive provenance and in part an unstable period in terms of tectonic activity. Geochemical classification of the sediments shows mostly sub-arkose with few sub-litharenites. Some major and trace elements display comprehensible correlation with Al2O3 confirming their possible hydraulic fractionation. The chemical index of alteration(CIA*), W* index, index of compositional variability(ICV), plagioclase index of alteration(PIA*) values and the ratio of Si O2/Al2O3, suggest low degrees of chemical weathering in the source areas as well as immature to moderately mature the sediments. The sediments suggest semi-arid climatic trends within oxic deltaic depositional conditions during the Holocene, at 3–12 ka. Whole rock geochemistry and discrimination diagrams demonstrate the continental signature derivatives, which might have been derived from the felsic to intermediate igneous rocks(granitic plutonic rocks) as well as from quartzose sedimentary/metamorphic provenance. These typical sources are present in a vast region of the Himalayan belt and catchment areas of Ganges. The tectonic setting of the sediments demarcates typically passive margin with slightly continental arc system.

关键词：地球化学特征氧化还原条件化学风化沉积物构造背景孟加拉国气候趋势全新世

Fe65-engineered neuronal exosomes encapsulating corynoxine-B ameliorate cognition and pathology of Alzheimer’s disease

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Signal Transduction and Targeted Therapy 2023年第11期8卷 5481-5494页

作者： Ashok Iyaswamy Abhimanyu Thakur Xin-Jie Guan Senthilkumar Krishnamoorthi Tsz Yan Fung Kejia Lu Isha Gaurav Zhijun Yang Cheng-Fu Su Kwok-Fai Lau Kui Zhang roy Chun-Laam Ng Qizhou Lian King-Ho Cheung Keqiang Ye Huanhuan Joyce Chen Min Li Mr.&Mrs.Ko Chi-Ming Centre for Parkinson’s Disease Research School of Chinese MedicineHong Kong Baptist UniversityHong Kong SARChina Pritzker School of Molecular Engineering The University of ChicagoChicagoILUSA Ben May Department for Cancer Research The University of ChicagoChicagoILUSA School of Chinese Medicine Hong Kong Baptist UniversityHong Kong SARChina School of Life Sciences The Chinese University of Hong KongHong Kong SARChina Division of Neuroscience School of Biological SciencesFaculty of BiologyMedicine and HealthManchester Academic Health Science CentreUniversity of ManchesterManchesterUnited Kingdom Department of Medicine Li Ka Shing Faculty of MedicineThe University of Hong KongPok Fu LamHong Kong SARChina Prenatal Diagnostic Center and Cord Blood Bank Guangzhou Women and Children’s Medical CenterGuangzhou Medical UniversityGuangzhouChina HKUMed Laboratory of Cellular Therapeutics the University of Hong KongPok Fu LamHong Kong SARChina Faculty of Life and Health Sciences Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhenChina

Alzheimer’s disease(AD)is a neurodegenerative disorder characterized by the predominant impairment of neurons in the hippocampus and the formation of amyloid plaques,hyperphosphorylated tau protein,and neurofibrillary tangles in the *** overexpression of amyloid-βprecursor protein(APP)in an AD brain results in the binding of APP intracellular domain(AICD)to Fe65 protein via the C-terminal Fe65-PTB2 interaction,which then triggers the secretion of amyloid-βand the consequent pathogenesis of ***,targeting the interaction between APP and Fe65 can offer a promising therapeutic approach for ***,exosome,a type of extracellular vesicle with diameter around 30–200 nm,has gained much attention as a potential delivery tool for brain diseases,including AD,due to their ability to cross the blood–brain barrier,their efficient uptake by autologous cells,and their ability to be surface-modified with target-specific receptor ***,the engineering of hippocampus neuron cell-derived exosomes to overexpress Fe65,enabled the development of a novel exosome-based targeted drug delivery system,which carried Corynoxine-B(Cory-B,an autophagy inducer)to the APP overexpressed-neuron cells in the brain of AD *** Fe65-engineered HT22 hippocampus neuron cell-derived exosomes(Fe65-EXO)loaded with Cory-B(Fe65-EXO-Cory-B)hijacked the signaling and blocked the natural interaction between Fe65 and APP,enabling APP-targeted delivery of ***,Fe65-EXO-Cory-B induced autophagy in APP-expressing neuronal cells,leading to amelioration of the cognitive decline and pathogenesis in AD mice,demonstrating the potential of Fe65-EXO-Cory-B as an effective therapeutic intervention for AD.

关键词： Alzheimer gained loaded

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在线社交网络中群体影响力的建模与分析

计算机学报 2021年第6期44卷 1064-1079页

作者：孟青刘波张恒远孙相国曹玖新李嘉伟东南大学计算机科学与工程学院南京211189 东南大学网络空间安全学院南京211189 萨斯喀彻温大学计算机科学系加拿大萨斯卡通市S7N 5C9

移动互联网技术的飞速发展,给社交网络平台带来了新的颠覆性的转变,也不断地改变着人们的生产、生活和交流方式.在线社交网络由于其特有的注册开放性、发布信息自由性、用户兴趣趋同性等特点,已经超越传统媒体,成为人们传播消息、获取... 详细信息

移动互联网技术的飞速发展,给社交网络平台带来了新的颠覆性的转变,也不断地改变着人们的生产、生活和交流方式.在线社交网络由于其特有的注册开放性、发布信息自由性、用户兴趣趋同性等特点,已经超越传统媒体,成为人们传播消息、获取新闻和接收实时信息的主要途径.同时,社交网络中用户之间的各种关系类型多样、相互交织、相互影响,促使用户生活在复杂的在线群体网络环境中,使得用户的在线行为时刻都受到所属的多种群体环境的影响作用.现有的针对在线群体环境影响的研究大多依据静态的、单一的网络结构对社交网络进行建模,而网络中通常存在多种类型的、动态的社会关系,较少研究能同时考虑多种类型的用户关系,建模社交网络中复杂环境下用户受到的影响作用.本文对用户所处的多类在线群体环境进行分析,挖掘用户所能感知的不同类型的群体环境,建模多维群体环境下用户所受的影响作用.首先,从用户间的社交关系类型出发,对在线社交网络中复杂的网络拓扑关系进行分类挖掘,分析用户可能感知的不同维度的在线群体环境,并提出静态群体环境和动态群体环境的定义和挖掘方法.其次,在不同的在线社交群体环境下,从宏观角度量化环境中用户所感知的群体结构特征,并从微观角度建模并模拟用户间的影响机制,提出了基于图注意力网络的融合多维在线群体环境的影响力模型.最后,以在线社交网络中用户的转发行为为例,研究多维群体环境影响下的用户行为模式,并在真实数据集上,基于群体影响力模型预测个体转发行为状态,验证模型的合理性和有效性.实验结果表明,本文提出的群体影响力模型能够更有效地描述在线社交网络中用户所属群体对用户的影响作用,并且在用户转发行为状态预测方面,比现有的群体影响力模型在综合评价指标F1值方面最高可以提升33%,在AUC值方面可提升16%.

关键词：在线社交网络群体群体影响力环境感知图注意力网络

基于PSInSAR技术的老采空区地表沉降监测研究

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煤炭技术 2017年第5期36卷 175-177页

作者：邹昊邓喀中中国矿业大学环境与测绘学院江苏徐州221116 江苏省资源环境信息工程重点实验室江苏徐州221116

为掌握老采空区地表下沉规律,基于11景Radarsat-2影像数据,采用sta MPS软件的PS方法对峰峰矿区某矿老采空区地表进行形变监测,获得了2015年5月~2016年3月该矿老采空区的地表沉降情况。分析结果表明:老采空区地表下沉速率呈周期性变化规... 详细信息

为掌握老采空区地表下沉规律,基于11景Radarsat-2影像数据,采用sta MPS软件的PS方法对峰峰矿区某矿老采空区地表进行形变监测,获得了2015年5月~2016年3月该矿老采空区的地表沉降情况。分析结果表明:老采空区地表下沉速率呈周期性变化规律,总体呈下降趋势,靠近停采线附近下沉量较大,同时还建立了采空区工作面累积下沉与停采时间的关系式,为评价老采空区地表形变研究提供了基础。

关键词： PSInSAR 老采空区地表沉降 staMPS

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单层柱面网壳抗火性能分析

消防科学与技术 2013年第9期32卷 952-955页

作者：苟卡西张芳安顺市消防支队贵州安顺561000 贵州航天红光机械制造有限公司贵州遵义563003

通过在6个工况组合的数值模拟基础上,对单层柱面网壳结构常温下和不同受火区域情况下应力应变、支座效应和稳定性的分析比较,得出单层柱面网壳属于敏感性受力结构,在火灾高温下显得尤为突出。防火设计中应加强受力薄弱区域和强约束部位... 详细信息

通过在6个工况组合的数值模拟基础上,对单层柱面网壳结构常温下和不同受火区域情况下应力应变、支座效应和稳定性的分析比较,得出单层柱面网壳属于敏感性受力结构,在火灾高温下显得尤为突出。防火设计中应加强受力薄弱区域和强约束部位的保护,同时可在设计过程中进行火灾工况的概率分析以提高结构防火设计效率和结构安全可靠度。

关键词：单层柱面网壳抗火性能有限元分析

基于staMPS技术的矿区开采沉陷监测与分析

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煤矿开采 2016年第5期21卷 71-74页

作者：李达邓喀中陈华杨俊凯高明章中国矿业大学环境与测绘学院江苏徐州221116 江苏省资源环境信息工程重点实验室江苏徐州221116 兖州煤业股份有限公司兴隆庄煤矿山东兖州272102

针对DIn SAR技术易受时空失相关、大气相位延迟等影响的问题,采用sta MPS方法对12景ALOS PALSAR数据进行时序处理。首先获取了采动区边缘区域2012-2014年的非线性时序沉降量,在工作面边缘地区走向方向和倾向方向各选取若干点,提取各点... 详细信息

针对DIn SAR技术易受时空失相关、大气相位延迟等影响的问题,采用sta MPS方法对12景ALOS PALSAR数据进行时序处理。首先获取了采动区边缘区域2012-2014年的非线性时序沉降量,在工作面边缘地区走向方向和倾向方向各选取若干点,提取各点的时序沉降量进行时序分析,掌握了采动区在不同时间段里的地表下沉情况。实验表明sta MPS技术可为矿区的开采沉陷监测与分析提供新的手段。

关键词： staMPS技术开采沉陷非线性沉降时序分析形变监测