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Paleoclimate and Paleoenvironment of Gonghe Basin, Qinghai-tibet Plateau, During the Lastdeglacial: Weathering, Erosion and Vegetation Cover Affect Clay Mineral Formation

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Acta Geologica Sinica(English Edition) 2014年第2期88卷 647-660页

作者： SUN Qingfeng Christophe colin Faculty of Geography Northwest Normal University Laboratoire des Interactions et Dynamique des Environnements de Surface (IDES) UMR 8148CNRS Université de Paris-Sud

With the analysis of the sources and formation mechanism of the clay minerals in the sediment core from the Dalianhai lake in the Gonghe Basin,northeastern tibet-Qinghai Plateau,clay mineral composition proxies,grain-size and carbonate contents have been employed for high-resolution study in order to reconstruct East Asian Summer Monsoon （EASM） over the northeastern tibet-Qinghai Plateau during the *** study also extended to establish a relationship between vegetation cover changes and erosion during the last 14.5 ka with pollen record and clay mineral ***/kaolinite and smectite/（illite＋chlorite） ratios allow us to assess hydrolysis conditions in lowlands and/or physical erosion process in highlands of the Gonghe *** 12.9 Cal ka BP,both mineralogical ratios show low values indicative of strong physical erosion in the basin with a dominant cold and dry *** 12.9 Cal ka BP,an increase in both mineralogical ratios indicates enhanced chemical weathering in the basin associated with a warm and humid *** beginning of Holocene is characterized by high smectite/（illite＋chlorite） and smectite/kaolinite ratios that is synchronous as with deposition of many peat laminae,implying the best warm and humid conditions specifically between 8.0 to 5.5 Cal ka *** time interval after 5.0 Cai ka BP is characterized by a return to high physical erosion and low chemical weathering with dry climate conditions in the *** variations of clay mineral assemblages with previous pollen results,we observe a rapid response in terms of chemical weathering and physical erosion intensity to a modification of the vegetation cover in the basin.

关键词： clay minerals vegetation Gonghe Basin tibet-Qinghai Plateau Asian monsoon Holocene

Infectious disease emergence and global change: thinking systemically in a shrinking world

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Infectious Diseases of Poverty 2012年第1期1卷 31-47页

作者： colin D Butler National Centre for Epidemiology and Population Health College of Medicine Biology and Environment Australian National UniversityCanberraAustralia

Background:Concern intensifying that emerging infectious diseases and global environmental changes that could generate major future human ***:A focused literature review was undertaken,partly informed by a forthcoming report on environment,agriculture and infectious diseases of poverty,facilitated by the Special Programme for tropical ***:More than ten categories of infectious disease emergence exist,but none formally analyse past,current or future burden of *** evidence suggests that the dominant public health concern focuses on two informal *** important is the perceived threat of newly recognised infections,especially viruses that arise or are newly discovered in developing countries that originate in species exotic to developed countries,such as non-human primates,bats and *** pathogens may be transmitted by insects or bats,or via direct human contact with *** second group is new strains of influenza arising from intensively farmed chickens or pigs,or emerging from Asian“wet markets”where several bird species have close *** forms appear justified because of two great pandemics:HIV/AIDS(which appears to have originated from bushmeat hunting in Africa before emerging globally)and Spanish influenza,which killed up to 2.5%of the human population around the end of World War *** appreciated is the contribution of the milieu which appeared to facilitate the high disease burden in these ***,excess anxiety over emerging infectious diseases diverts attention from issues of greater public health importance,especially:(i)existing(including neglected)infectious diseases and(ii)the changing milieu that is eroding the determinants of immunity and public health,caused by adverse global environmental changes,including climate change and other components of stressed life and civilisation-supporting ***:the focus on novel pathogens and minor forms of anti-micr

关键词： immunity formally originated

Localization and the possible role of plasminogen activators and inhibitors in early stages of placentation

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Chinese Science Bulletin 2000年第22期45卷 2056-2062页

作者： Ockleford colin D Department of Pre-Clinical Sciences University of LeicesterLeicester LEI 9HNUK

the distribution of mRNAs of tissue type (t) and urokinase type (u) plasminogen activator (PA) plus their corresponding inhibitors, type-1 (PAI-1) and type-2 (PAI-2) have been studied in the tissues of human first and second trimester placentae by in situ hybridization. the results show that: (i) All the molecules, tPA, uPA, PAI-1 and PAI-2, were identified in the blood vessels, the majority of extravillous trophoblastic cells of the decidual layer between Rohr’s and Nitabuch’s stria and in the trophoblast cells lining the chorionic plate, basal plate, intercotyledonary septae and cytotrophoblast cells of the chorionic villous tree. (ii) No expression of such probes was observed in the basal and chorionic plate, glandular cells of the decidua, the septal tissues or the villous core mesenchyme. the co-distribution of the molecules observed suggests that the co-ordinated expression of the activators and inhibitors in various cells of the placental tissue may play a role in angiogenesis related to

关键词： plasminogen activator plasminogen activator inhibitor placentation angiogenesis in situ hybridization.

Coupler force and fatigue assessments with stochasticdraft gear frictions

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Journal of traffic and transportation Engineering(English Edition) 2023年第1期10卷 1-12页

作者： Qing Wu colin Cole Maksym Spiryagin Centre for Railway Engineering Central Queensland UniversityRockhamptonQLD 4701Australia

train dynamics and component fatigue assessments are important steps towards successful operations of long heavy haul *** train dynamics(LtD)simulation is an effective and efficient approach in this *** gear friction has been known to have a strong stochastic ***,relevant train dynamics simulations have not been reported in open *** paper uses experimental data to extract the stochastic feature of draft gear *** stochastic feature is then introduced into LtD *** force and fatigue damage assessments were conducted by simulating a heavy haul train that has 244 vehicles and weighs nearly 30,000 *** results show that average in-train force variations due to stochastic friction were 55 and 40 kN for the traction and air brake cases respectively;maximum force variations were 207 and 98 kN for the traction and air brake cases *** fatigue calculations are even more sensitive to stochastic draft gear friction;the largest variations can be up to 700 times different due to the strong nonlinearity of fatigue calculation *** friction is an unavoidable nature in friction draft *** using stochastic draft gear friction can deliver results that are more robust and reliable.

关键词： Stochastic friction Draft gear train dynamics Coupler fatigue Laboratory testing

Localization and possible role of membrane type metallo-proteinase and tissue inhibitors of metalloproteinase-1 in early stages of placentation

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Chinese Science Bulletin 2000年第16期45卷 1484-1489页

作者： Ockleford colin D. Department of Pre-Clinical Sciences University of LeicesterLeicester LEI 7RHUK

Human placental tissues from the first and second trimesters of gestation have been investigated using riboprobe in situ hybridisation of mRNA sequences coding for membrane type metalloproteinase (Mt-1-MMP) and tissue inhibitors of metalloproteinase-1 (tIMP-1). Results show that (i) both mRNAs express at a relatively high level in the chorion laeve trophoblast cells and the adjacent decidual cells of fetal membrane; (ii) the most abundant expression of the two mRNAs was found in the extravillous trophoblast between Rohrs and Nitabuch striae of basal plate, trophoblast shell and gland cells of the decidua; (iii) isolated or small groups of cytotrophoblast cells in the chorionic villi and in the cells lining arterioles in decidua and stem villi also expressed both Mt-1-MMP and tIMP-1 at defferent extents. the data suggest that the coordinated expression of the Mt-MMP and its inhibitor tIMP in defferent cells of the placental tissue may play an essential role in trophoblast invasion and angiogenesis

关键词： placenta trophoblast basal plate fetal membrane Mt-l-MMP tIMP-1 in situ hybridization.

Refining spatial neighbourhoods to capture terrain effects

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Ecological Processes 2012年第1期1卷 98-108页

作者： trisalyn A Nelson colin Robertson Spatial Pattern Analysis and Research Lab Department of GeographyUniversity of VictoriaPO Box 3060VictoriaBritish ColumbiaV8W 3R4SCanada Department of Geography and Environmental Studies Wilfrid Laurier UniversityWaterlooOntarioN2L 3C5Canada

Introduction:Spatially explicit ecological research has increased substantially in the past 20 *** spatial approaches require the definition of a spatial neighbourhood or the region over which spatial relationships are modelled or *** neighbourhood definitions impact analysis results,and there are benefits in considering neighbourhood definitions that better capture ecological *** goal of this research is to present a simple and flexible approach in constraining ecological spatial neighbourhoods using terrain ***:Using watershed boundaries,we can restrict spatial neighbourhoods from combining populations or processes that should be separated by terrain *** demonstrate the need for ecological constraints by way of a simulation study and highlight our approach with a case study examining mountain pine beetle(Dendroctonus ponderosae,Coleoptera;Hopkins)infestation hot ***:Our results demonstrate how failure to constrain neighbourhoods can lead to errors when the spatial signals from unrelated populations are ***,unconstrained spatial neighbourhoods can unintentionally detect spatial relationships across many ***:there will be benefits to studies that develop new,ecology-based approaches in defining spatial neighbourhoods that better illuminate ecological function of phenomena under study.

关键词： spatial weights spatial analysis spatial ecology hot spots topography

What are universities for?

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Chinese Science Bulletin 2011年第23期56卷 2506-2517页

作者： Geoffrey BOULtON colin LUCAS the University of Edinburgh University of Oxford

Governments worldwide rightly regard universities as fundamental to the achievement of many national priorities. But it is the paper’s contention that many misunderstand their true benefit to society. Investments in universities are increasingly based on the belief that the science labs in particular of research-intensive universities can be the source of a continuous stream of people and ideas that will spawn innovative and fast growing companies to form the nexus of the knowledge-based economy. this belief is a source of misconceived policies that offer only ultimate disillusion. It is the totality of the university enterprise that is important, as the only place where that totality of ourselves and our world is brought together, and which makes it the strongest provider of the rational explanation and meaning that societies need. In research, universities create new possibilities; in teaching, they shape new people. Its graduates learn to seek the true meaning of things: to distinguish between the true and the merely seemingly true, to verify for themselves what is stable in that very unstable compound that often passes for knowledge. It is the complex, interacting whole of the university that is the source of the separate economic, social, cultural and utilitarian benefits valued by society. It needs to be understood, valued and managed as a whole. these perceptions are a direct challenge to not only to governments but to university administrators who have been either cowed or seduced into the slipshod thinking that is leading to demands that universities cannot satisfy, whilst obscuring their most important contributions. the challenge to both is to permit autonomy without oppressive accountability, and to give staff and students the freedom to think, speculate and research. these are the very conditions of the personal and collective creativity that are the sources of a university’s deepest benefits to its society.

关键词：研究型大学社会需要经济关系工作人员社会根源不稳定管理员实验室

Hoare logic-based genetic programming

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Science China(Information Sciences) 2011年第3期54卷 623-637页

作者： JOHNSON colin G. Computing Laboratory University of Kent

Almost all existing genetic programming systems deal with fitness evaluation solely by testing. In this paper, by contrast, we present an original approach that combines genetic programming with Hoare logic with the aid of model checking and finite state automata, henceby proposing a brand new verification-focused formal genetic programming system that makes it possible to evolve reliable programs with mathematically-verified properties.

关键词： genetic programming program verification Hoare logic model checking finite state automata

Modeling grammatical evolution by automaton

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Science China(Information Sciences) 2011年第12期54卷 2564-2573页

作者： colin G.JOHNSON School of Computing University of Kent

twelve years have passed since the advent of grammatical evolution (GE) in 1998, but such issues as vast search space, genotypic readability, and the inherent relationship among grammatical concepts, production rules and derivations have remained untouched in almost all existing GE researches. Model-based approach is an attractive method to achieve different objectives of software engineering. In this paper, we make the first attempt to model syntactically usable information of GE using an automaton, coming up with a novel solution called model-based grammatical evolution (MGE) to these problems. In MGE, the search space is reduced dramatically through the use of concepts from building blocks, but the functionality and expressiveness are still the same as that of classical GE. Besides, complex evolutionary process can visually be analyzed in the context of transition diagrams.

关键词： genetic programming grammatical evolution finite state automaton model