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Crack spacing of unsaturated soils in the critical state

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Chinese Science Bulletin 2009年第12期54卷 2008-2012页

作者： sun jichao WANG GuangQian sun QiCheng State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China

The cracking mechanism of unsaturated soils due to evaporation is poorly understood, and the magnitude of crack spacing is usually hard to estimate. In this work, cracks were postulated to occur succedently rather than simultaneously, that is, secondary cracks appear after primary cracks as evaporation continues. Formulae of the secondary crack spacing and secondary trend crack spacing were then derived after stress analysis. The calculated spacing values were consistent with the published experimental data. Meanwhile, the effect of the Poisson ratio on the crack spacing was analyzed, which showed that the magnitude of crack spacing was proportional to the Poisson ratio in the range of [0.30, 0.35].

关键词：裂缝间距非饱和土临界状态开裂机理应力分析实验数据蒸发量泊松比

Response of Groundwater to Climate Change under Extreme Climate Conditions in North China Plain

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Journal of Earth Science 2014年第3期25卷 612-618页

作者： Ying Zhang Jincui Wang Jihong Jing jichao sun Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological Sciences

The North China Plain（NCP） is one of the water shortage areas of China. Lack of water resources restricted the economic and social development of North China area and resulted in deterioration of ecosystem and natural environment. Influenced by the climate change and human activities, the water circulation of NCP was largely changed and the crisis of water resources was aggravated. Therefore, it is important to study the features of the extreme climate and the response mechanism of groundwater to climate change. We analyzed the trend of climate change and extreme climate features in the past 60 years based on the monitoring data of meteorological stations. And then the response characteristics of groundwater to climate change were discussed. The average temperature of NCP was in an obviously upward trend. The overall precipitation variation was in a downward trend. The climate change in this area showed a warming-drying trend. The intensity of extreme precipitation displayed a trend of declining and then increasing from north to south as well as declining from eastern coastal plain to the piedmont plain. Grey correlation degree analysis indicated that groundwater depth had a close relationship with precipitation and human activities in NCP. The response of groundwater level to precipitation differed from the piedmont alluvial-pluvial plain to the coastal plain. The response was more obvious in the coastal plain than the piedmont alluvial-pluvial plain and the middle plain. The precipitation influenced the groundwater depth both directly and indirectly. Under the condition of extreme precipitation, the impact would aggravate, in the forms of rapid or lag raise of groundwater levels.

关键词： climate change groundwater response grey correlation extreme precipitation.

A Simulation Study on the Evolution of Groundwater Circulation Systems in Cenozoic Basins of Northern China

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Acta Geologica Sinica(English Edition) 1998年第1期72卷 100-107页

作者： SHI Dehong YIN Xia sun jichao YIN Zhengzhou Institute of Hydro geology and Engineering Geology CAGS Zhengding Hebei Province 050803

Three Cenozoic basins—the Qaidam basin, the Weihe graben-type basin and the North China plain—which are different in climatic conditions, geological settings and run—off types, are selected for the study. Based on an analysis of background information of the transect along the middle-latitude region, studies of groundwater dynamics, geochemistry, simulation of water circulation of the main elements as well as isotopic chronology, the information on global changes is collected, the formation of groundwater circulation systems and their evolution under stacked impacts of natural conditions and human activities are discussed, and a correlation is made between the evolutionary features of the above systems in these basins since 25 ka B.P. All these have laid a good foundation for further generalizing the evolutionary model of land water in northern China.

关键词： Cenozoic basins groundwater circulation system evolutionary modelling

The distribution and sources of polycyclic aromatic hydrocarbons in shallow groundwater from an alluvial-diluvial fan of the Hutuo River in North China

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Frontiers of Earth Science 2019年第1期13卷 33-42页

作者： Jincui WANG Yongsheng ZHAO jichao sun Ying ZHANG Chunyan LIU College of Environment and Resources Jilin UniversityChangchun 130026China Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological SciencesShijiazhuang 050061China

This paper has investigated the concentration and distribution of polycyclic aromatic hydrocarbons in shallow groundwater from an alluvial-diluvial fan of the Hutuo River in North concentration levels of *** show that the 16 priority polycyclic aromatic hydrocarbons range from 0 to 92.06 ng/L,do not conform to drinking water quality standards in China (GB 5749-2006).However,the concentration figures of priority polycyclic aromatic hydrocarbons are much lower than that of other studies conducted elsewhere in *** addition,highly-concentrated polycyclic aromatic hydrocarbons (50-92 ng/L)are fragmentarily *** composition of polycyelic aromatic hydrocarbons from this study indicates that low molecular polycyclic aromatic hydrocarbons are predominant in groundwater samples, medium molecular compounds occur at low concentrations,and high molecular hydrocarbons are not detected. The polycyclic aromatic hydrocarbon composition in groundwater samples is basically the same as that of gaseous samples in the atmosphere in this ***, the atmospheric input is assumed to be an important source of polycyclic aromatic hydrocarbons,no less than wastewater discharge,adhesion on suspended solids,and surface water *** of specific polycyclic aromatic hydrocarbons demonstrate that they mainly originate from wood or coal combustion as well as natural gas and partially from petroleum according to the result of principal component *** the whole,conclusions are drawn that the contamination sources of these polycyclic aromatic hydrocarbons are likely petrogenic and pyrolytic *** investigations by sampling topsoil,vadose soil,and the atmosphere can further verify aforementioned conclusions.

关键词： polycyclic aromatic hydrocarbons unconsolidated sedimentary aquifers groundwater protection hydrochemistry North China

Impairment of the autophagy-lysosomal pathway in Alzheimer’s diseases: Pathogenic mechanisms and therapeutic potential

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Acta Pharmaceutica Sinica B 2022年第3期12卷 1019-1040页

作者： Wei Zhang Chengchao Xu jichao sun Han-Ming Shen Jigang Wang Chuanbin Yang Department of Geriatrics Shenzhen People’s Hospital(the Second Clinical Medical CollegeJinan Universitythe First Affiliated HospitalSouthern University of Science and Technology)Shenzhen 518020China Integrated Chinese and Western Medicine Postdoctoral Research Station Jinan UniversityGuangzhou 510632China Artemisinin Research Center Institute of Chinese Materia MedicaChina Academy of Chinese Medical SciencesBeijing 100700China Faculty of Health Sciences University of MacaoTaipaMacao 999078China Guangdong Provincial Key Laboratory of New Drug Screening School of Pharmaceutical SciencesSouthern Medical UniversityGuangzhou 510515China

Alzheimer’s disease(AD),the most common neurodegenerative disorder,is characterized by memory loss and cognitive *** accumulation of misfolded protein aggregates including amyloid beta(Aβ)peptides and microtubule associated protein tau(MAPT/tau)in neuronal cells are hallmarks of *** far,the exact underlying mechanisms for the aetiologies of AD have not been fully understood and the effective treatment for AD is *** is an evolutionarily conserved cellular catabolic process by which damaged cellular organelles and protein aggregates are degraded via ***,there is accumulating evidence linking the impairment of the autophagy-lysosomal pathway with AD ***,the enhancement of autophagy to remove protein aggregates has been proposed as a promising therapeutic strategy for ***,we first summarize the recent genetic,pathological and experimental studies regarding the impairment of the autophagy-lysosomal pathway in *** then describe the interplay between the autophagy-lysosomal pathway and two pathological proteins,Aβand MAPT/tau,in ***,we discuss potential therapeutic strategies and small molecules that target the autophagy-lysosomal pathway for AD treatment both in animal models and in clinical ***,this article highlights the pivotal functions of the autophagy-lysosomal pathway in AD pathogenesis and potential druggable targets in the autophagy-lysosomal pathway for AD treatment.

关键词： Alzheimer’s disease(AD) Amyloid beta(Aβ)peptides MAPT/tau Autophagy-lysosomal pathway Autophagy enhancers Autophagy Mitophagy Neurodegenerative diseases

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冲刷致岸堤稳定的衰变

清华大学学报（自然科学版） 2010年第9期50卷 1346-1349页

作者：孙即超王光谦清华大学水利水电工程系水沙科学与水利水电工程国家重点实验室北京100084

四川"512"地震堰塞湖及由此导致的后期人工开挖的泄流槽冲刷问题的核心是不能预测河流冲刷下泄水槽的稳定性。该文展开室内试验,对试验获得的图片进行扭转平移,进而直接测量实验获得的图片,得到岸堤的坍塌开裂露头位置。提出路径损伤的... 详细信息

四川"512"地震堰塞湖及由此导致的后期人工开挖的泄流槽冲刷问题的核心是不能预测河流冲刷下泄水槽的稳定性。该文展开室内试验,对试验获得的图片进行扭转平移,进而直接测量实验获得的图片,得到岸堤的坍塌开裂露头位置。提出路径损伤的理论,根据路径损伤公式,计算得出冲刷下岸堤的路径损伤;并拟合出岸堤损伤的演变公式,通过此公式可以对岸堤的损伤坍塌进行预测。

关键词：河道稳定岸堤坍塌稳定性图像处理

Analysis of Groundwater Environmental Conditions and Influencing Factors in Typical City in Northwest China

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Journal of Groundwater Science and Engineering 2013年第2期1卷 60-73页

作者： Liu Jingtao sun jichao Zhu Liang Lv Xiaoli Liu Chunyan The Institute of Hydrogeology and Environmental Geology CAGS

The groundwater in the research area is characterized by alkalescence,generally over-high EC value,and relatively low dissolved oxygen and oxidation-reduction *** pollution is presented by abnormal acid-base,dissolved oxygen reduction,and conductivity *** overall situation of groundwater chemical field is controlled by natural conditions,the hydrochemical type has obvious zoning feature and changes from single type to multiple types from the river bank of the Yellow River to both sides,and the local abnormality is closely related to the intensity of human *** pollution scope and degree of inorganic toxicological indexes and organic indexes are strongly correlated with land utilization type,pollution source distribution,urbanization,and pollutant disposal of the city,the pollution in the petrochemical industrial area is the most serious,and the organic pollution tends to escalate and diffuse to the downstream.

关键词： Groundwater Environment Pollution Land Utilization Pollution Source Urbanization

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利用本原单位根构造正交变换

西安电子科技大学学报 2013年第5期40卷 157-162页

作者：孙际超周凯疏达安徽工程大学继续教育学院安徽芜湖241000 阜新供电公司变电运行工区辽宁阜新123000 安徽工程大学机械与汽车工程学院安徽芜湖241000

在整环R上,基于本原单位根提出一种新的正交变换,它概括了整数剩余类环、有限域、复数域上的正交变换及多项式变换,包括离散傅里叶变换、阿达玛变换、Chrestenson变换,可导出多实值对称变换、离散W变换和离散正弦型变换.证明了离散正弦... 详细信息

在整环R上,基于本原单位根提出一种新的正交变换,它概括了整数剩余类环、有限域、复数域上的正交变换及多项式变换,包括离散傅里叶变换、阿达玛变换、Chrestenson变换,可导出多实值对称变换、离散W变换和离散正弦型变换.证明了离散正弦型变换的正交性.所有这些变换基于与离散傅里叶变换的联系都有快速算法.该变换对系统掌握常用的变换和构造新的变换大有帮助.

关键词：本原单位根正交变换离散正弦型变换快速算法

MPZL1 as an HGF/MET signaling amplifier promotes cell migration and invasion in glioblastoma

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Genes & Diseases 2024年第5期11卷 70-73页

作者： Haimin Song Bowen Ni Xuetao Peng Weijuan Xu Shaochun Yang Runwei Yang Ziyu Wang Kaishu Li Rui Lin Yunxiao Zhang Jinglin Guo Kezhi Wu Guangwei Shi jichao sun Chunming He Yawei Liu Department of Neurosurgery The First Affiliated Hospital of Gannan Medical UniversityGanzhouJiangxi 341000China Department of Neurosurgery&Medical Research Center Shunde HospitalSouthern Medical University(The First People’s Hospital of Shunde Foshan)FoshanGuangdong 528300China Medical Research Center Shunde HospitalSouthern Medical University(The First People’s Hospital of Shunde Foshan)FoshanGuangdong 528300China Bidding and Procurement Office Shunde HospitalSouthern Medical University(The First People’s Hospital of Shunde Foshan)FoshanGuangdong 528300China Department of Neurosurgery Nanfang HospitalSouthern Medical UniversityGuangzhouGuangdong 510515China Department of Neurosurgery The Sixth Affiliated Hospital of Guangzhou Medical UniversityQingyuanGuangdong 511518China Department of Neurosurgery The First Affiliated Hospital of Shantou University Medical CollegeShantouGuangdong 515041China Department of Geriatrics Shenzhen People’s Hospital(The Second Clinical Medical CollegeJinan UniversityThe First Affiliated HospitalSouthern University of Science and Technology)ShenzhenGuangdong 518020China

The extremely poor prognosis of patients is largely due to hepatocyte growth factor(HGF)/MET signaling,which promotes migration and invasion of glioblastoma(IDH wildtype;GBM;WHO grade 4).1,2 Clinical trials targeting MET,the only receptor of HGF,have yielded unimpressive results in GBM.3,4 Here we found that HGF induced strong chemotaxis on GBM cells,but MET expression was extremely ***,therefore,used single-cell RNA sequencing(scRNA-seq)coupled with label-free proteome profiling to identify membrane proteins associated with HGF/MET signaling amplification in GBM and to provide a novel modulator,MPZL1,for HGF/MET-targeted therapy.

关键词： invasion prognosis Clinical