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Comparisons of Limit Analysis solutions and Random search solutions on slope Critical slip surface

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Communications in Nonlinear science and Numerical simulation 1998年第2期3卷 14-19页

作者： Jianfeng WANG (LNM, Institute of Mechanics, cas, Beijing 100080, China) LNM Institute of Mechanics CAS Beijing 100080 China

ＩｎｔｒｏｄｕｃｔｉｏｎＤｅｓｐｉｔｅｔｈｅｄｅｖｅｌｏｐｍｅｎｔｏｆｅｌａｓｔｉｃｐｌａｓｔｉｃｖｉｓｃｏｕｓｎｕｍｅｒｉｃａｌｍｅｔｈｏｄｓｆｏｒｔｈｅａｎａｌｙｓｉｓｏｆｓｌｏｐｅｓ，ｔｒａｄｉｔｉｏｎａｌ... 详细信息

ＩｎｔｒｏｄｕｃｔｉｏｎＤｅｓｐｉｔｅｔｈｅｄｅｖｅｌｏｐｍｅｎｔｏｆｅｌａｓｔｉｃｐｌａｓｔｉｃｖｉｓｃｏｕｓｎｕｍｅｒｉｃａｌｍｅｔｈｏｄｓｆｏｒｔｈｅａｎａｌｙｓｉｓｏｆｓｌｏｐｅｓ，ｔｒａｄｉｔｉｏｎａｌｔｅｃｈｎｉｑｕｅｓｂａｓｅｄｏｎ...

关键词： limit state analysis upper bound theorem random searching slip surface slope stability plasticity

CHALLENGEs AND CORREsPONDING POLICIEs FOR CHINA's URBAN sUsTAINABLE DEVELOPMENT

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Journal of Geographical sciences 1996年第1期6卷 72-77页

作者： Gu Chaolin(Institute of Geography, cas, Beijing 100101People’s Republic of China) Inst of Geography CAS Beijing 100101 China

since the late 1970s, China's economy has been growing very fast with an average rate of over 8 percent annually. Urbanization has become the indicator of economic and secial deveopment in China. Rapid growth of oromy in China pushed the process of urbanization. since 1978, China's urban non-agricultural population has grown from under 113.4 million in 1977 to 176.09 million in 1993. The number of cities increased from 188 to 617 in 1994. With urban economic activities making up an increasing share of GDP, preductivity of urban economy will heavily influence economic growth. In eastern coastal area, because economy of larger scale and agglomeration has been made more productive, the forces contributing to urban growth bome *** number of cities has increased from 78 to 247 since 1980. Urban population was over 90 million. The urbanization level reached 31.5 peed. Four megalopolises have been emerged, they are : the shanghai -Nanjing-Hangzhou region, the Pearl River Delta region, the Beijing-Tianjin- Tangshan region and the shenyang-Dalian region. According to statistics, the area of these four regions occupies about 2.6 perat of China's total territory, but their GDP has exceeded 35 percent of the country's total. However, the rapid urbanization also resulted in a series of problems on deveopment and environment.

关键词： urbanization environmental protection sustainable development urban fringe China

Darwin and the cirripedes: Insights and dreadful blunders

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Integrative Zoology 2009年第3期4卷 316-322页

作者： jean s.DEUTsCH UMR 7622 Developmental Biology Pierre and Marie Curie University(Paris 6)

Charles Darwin’s favorite animals were cirripedes(barnacles).Indeed,he worked intensively on cirripedes during the years he was maturing his thoughts regarding his theory,which eventually led to the publication of The Origin of *** I present some of Darwin’s achievements in the morphology,systematics and biology of these small marine invertebrates,and also,in light of our present knowledge,some mistakes he made.

关键词： cirripedes Darwin homology.

Microbiota-host interplay at the gut epithelial level,health and nutrition

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Journal of Animal science and Biotechnology 2017年第2期8卷 327-334页

作者： jean-Paul Lallès Division of Human Nutrition Division INRA Clermont-Ferrand France Human Nutrition Research Center-West Nantes France

Growing evidence suggests the implication of the gut microbiota in various facets of health and disease. In this review, the focus is put on microbiota-host molecular cross-talk at the gut epithelial level with special emphasis on two defense systems： intestinal alkaline phosphatase（IAP） and inducible heat shock proteins（iHsPs）. Both IAP and iHsPs are induced by various microbial structural components（e.g. lipopolysaccharide, flagellin, CpG DNA motifs）,metabolites（e.g. n-butyrate） or secreted signal molecules（e.g., toxins, various peptides, polyphosphate）. IAP is produced in the small intestine and secreted into the lumen and in the interior milieu. It detoxifies microbial components by dephosphorylation and, therefore, down-regulates microbe-induced inflammation mainly by inhibiting NF-κB pro-inflammatory pathway in enterocytes. IAP gene expression and enzyme activity are influenced by the gut microbiota. Conversely, IAP controls gut microbiota composition both directly, and indirectly though the detoxification of pro-inflammatory free luminal adenosine triphosphate and inflammation inhibition. Inducible HsPs are expressed by gut epithelial cells in proportion to the microbial load along the gastro-intestinal tract. They are also induced by various microbial components, metabolites and secreted molecules. Whether iHsPs contribute to shape the gut microbiota is presently unknown. Both systems display strong anti-inflammatory and anti-oxidant properties that are protective to the gut and the host. Importantly, epithelial gene expressions and protein concentrations of IAP and iHsPs can be stimulated by probiotics, prebiotics and a large variety of dietary components, including macronutrients（protein and amino acids, especially L-glutamine, fat, fiber）, and specific minerals（e.g. calcium）and vitamins（e.g. vitamins K1 and K2）. some food components（e.g. lectins, soybean proteins, various polyphenols） may inhibit or disturb these systems. The general cel ular and molecula

关键词： Diet Gut Inducible heat shock protein Inflammation Intestinal alkaline phosphatase Microbiota

Multi-scale calculation of settling speed of coarse particles by accelerated stokesian dynamics without adjustable parameter

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Acta Mechanica sinica 2009年第3期25卷 303-310页

作者： Long Wang Jiachun Li Jifu Zhou Institute of Mechanics, cas, 100190 Beijing, China Institute of Mechanics CAS 100190 Beijing China

The calculation of settling speed of coarse particles is firstly addressed, with accelerated stokesian dynamics without adjustable parameters, in which far field force acting on the particle instead of particle velocity is chosen as dependent variables to consider inter-particle hydrodynamic interactions. The sedimentation of a simple cubic array of spherical particles is simulated and compared to the results available to verify and validate the numerical code and computational scheme. The improved method keeps the same computational cost of the order O（NlogN） as usual accelerated stokesian dynamics does. Then, more realistic random suspension sedimentation is investigated with the help of Mont Carlo method. The computational results agree well with experimental fitting. Finally, the sedimentation of finer cohesive particle, which is often observed in estuary environment, is presented as a further application in coastal engineering.

关键词： sedimentation stokesian dynamics Many-body interactions Multi-scale

Topological to trivial insulating phase transition in stanene

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Nano Research 2016年第3期9卷 774-778页

作者： Michel Houssa bas van den Broek Konstantina Iordanidou Anh Khoa Augustin Lu Geoffrey Pourtois jean-Pierre Locquet Valery Afanas'ev Andre stesmans Department of Physics and Astronomy University of Leuven Celestijnenlaan 200D B-3001 Leuven Belgium imec 75 Kapeldreef B-3001 Leuven Belgium

Electronic properties of stanene, the sn counterpart of graphene are theoretically studied using first-principles simulations. The topological to trivial insulating phase transition induced by an out-of-plane electric field or by quantum confinement effects is predicted. The results highlight the potential to use stanene nanoribbons in gate-voltage controlled dissipationless spin-based devices and are used to set the minimal nanoribbon width for such devices, which is typically approximately 5 nm.

关键词： two-dimensional (2D)materials topological insulators density functional theory(DFT) simulations electronic structure

Physiological sex differences in microglia and their relevance in neurological disorders

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Neuroimmunology and Neuroinflammation 2020年第1期7卷 13-22页

作者： Natalia Yanguas-casás Grupo de Investigación en Linfomas Instituto Investigación Sanitaria Puerta de Hierro-Segovia de Arana (IDIPHISA)Majadahonda 28222Spain

Microglia are the resident immune cells in the brain and maintain homeostasis and functionality of this tissue. These cells are key producers of immune mediators, such as cytokines and chemokines, are critical for normal brain development, and affect neurogenesis, axonal migration, synapse formation and function, and programmed cell death, among others. sex differences exist in many of these processes throughout brain development up to adulthood and the aged brain. In the last few years, sex differences in microglia responses, brain colonization, and number and morphology within the developing brain have drawn the attention of researchers as a potential explanation to the sex differences in the brain and due to their potential relevance in the incidence, prevalence, and outcome of many neurological disorders. In this review, we summarize the sex differences of microglial cell functions and their potential relevance in physiological as well as pathological conditions in the brain.

关键词： Microglia sex differences functional responses neurological disorders

THE RIsK AssEssMENT OF THE LONG-DIsTANCE OILPIPELINE ENGINEERING

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Journal of Geographical sciences 1996年第1期6卷 78-83页

作者： Wang Jinghua Mu Congru(Institute of Geography, cas, Beijing 100101People’s Republic of China) Institute of Geography CAS Beijing 100101 China

The oilfield construction and long-distance oil pipeline engineering has been developed extensively in China. The risk assessment of oil industry will, however, be an important objective to cope with the development of oil industry , The risk assessment of oil industry has many subjects worthy to be *** major purpose of the paper is to research the risk cases of long-distance oil pipeline engineering in Ganshu and shaanxi provinces.

关键词： long-distance oil pipeline risk assessment engineering Gansu shaanxi

REGIONAL DIFFERENTIATION OF CRITICAL CONCENTRATION OF ARsENIC(As) AND CADMIUM (Cd) IN MAIN sOIL TYPEs OF CHINA

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Journal of Geographical sciences 1996年第2期6卷 60-65页

作者： Luo Jinfa Xia Zenglu(Institute of Geography, cas, Beijing 100101People’s Republic of China ) Inst of Geography CAS Beijing 100101 China

studies of critical concentration distribution features of polluted elements of Cd and As in main soil types of China, such as laterite, crimson soil, purplish soil, yellow brown soil, brunisolic soil, black soil, cinnamon soil and sierozem revealed that soil types vary in different zones, so do their critical *** critical concentration has a zonal differentiation with the distribution of soil types from south to north, and from east to west. The critical concentration of Cd increases from south to north (yellow brown soil,brunisolic soil and cinnamon soil),and from east to west (black soil and sierozem). This coincides With changes of climate zones and soil zones. On the contrary, the critical concentration of Asdecreases from south to north and from east to west.

关键词： soil types critical level As Cd regional differentiation