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On Inverse Limits and Direct Limits for Fuzzy Topological Spaces

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模糊系统与数学 2010年第1期24卷 45-50页

作者： A.Behera j.K.Sahu Department of Mathematics National Institute of Technology Department of Mathematics G.M.College

Li has introduced the concepts of inverse system and direct system for fuzzy topological spaces and studied inverse limits and direct limits on such spaces by presenting the explicit constructions of these *** this paper some important concepts of fuzzy topology,such as,product fuzzy topology,quotient fuzzy topology,fuzzy continuity etc.,are used for further study of inverse limits and direct limits for fuzzy topological spaces.

关键词：模糊拓扑逆向极限方向极限代数

Dyeing of Polypropylene Fibers with Vat Dyes

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journal of Donghua University(English Edition) 2006年第5期23卷 15-19页

作者：刘航 ETTERS j . Nolan LEONAS Karen K Department of Textiles Merchandising & Interiors University of Georgia Athens Georgia 30605 USA

Polypropylene fibers have been extensively used in a variety of/products, including carpets and upholstery, due to their non-absorbency, good weather resistance, good resistance to macroorgamsms and so on. Because of their hydrophobic and highly crystalline nature, those well-established conventionai dyeing processes are difficult to apply to unmodified polypropylene. Colors of polypropylene fibers are primarily obtained by mass coloration which has the disadvantages of limited number of colors available and difficulties in inventory control due to the rapidly changing color needs of the market. In this paper, the use of vat dyes to dye polypropylene fabrics is investigated. Seventeen vat dyes were screened and factors influencing uptake of dyes by polypropylene fabrics were studied.

关键词： pol ypropylene vat dye leuco acid vat dye.

Geoparks： Celebrating Earth heritage, sustaining Local communities

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Episodes 2005年第4期28卷 274-278页

作者： Patrick j. Mc Keever Nickolas Zouros Geological Survey of Northern Ireland Colby House Stranmillis Court Belfast BT9 5BF Ireland. Department of Geography University of the Aegean University Hill Mytilene GR-81100 Hellenic Republic.

For too long Earth Science has been the poor relative to Natural Sciences when it comes to conservation, preservation and public promotion. Today, however, in 25 territories across Europe, a combination of Earth Scientists, economists, professional marketers and local people are working together to promote the geological heritage of their areas. These European Geoparks not only advance the protection of their geological heritage but they also use it, in a truly sustainable way, to promote the economic well-being of the people who live there. With the full endorsement of UNESCO, this concept of geoparks is spreading to other parts of the world and is rapidly developing into a global concept. This article looks in detail at the geopark idea -- exactly what geoparks are, how they function, and what benefits they can bring both to geology and to the public.

关键词：地质公园地貌地质条件生态系统地质多样性

Speculation on the timing and nature of Late Pleistocene hunter-gatherer colonization of the Tibetan Plateau

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Chinese Science Bulletin 2003年第14期48卷 1510-1516页

作者： P.j.Brantingham MAHaizhou j.W.Olsen GAOXinq D.B.Madsen D.E.Rhode DepartmentofAnthropology UniversityofCaliforniaLosAngelesCA90095USA InstituteofSaltLakes ChineseAcademyofSciencesXining810008China DepartmentofAnthropology UniversityofArizonaAZ85721USA InstituteofVertebratePaleontologyandPaleoanthropology ChineseAcademyofSciencesBeiiing100044.China DesertResearchInstitute NV89512USA

Hunter-gatherer populations in greater northeast Asia experienced dramatic range expansions during the early Upper Paleolithic (45—22 ka) and the late Upper Paleolithic (18—10 ka), both of which led to intensive occupations of cold desert environments including the Mongolian Gobi and northwest China. Range contractions under the cold, arid extremes of the Last Glacial Maximum (LGM, 22—18 ka) may have entailed widespread population extirpations. The high elevation Qinghai-Tibetan Plateau is significantly more extreme in both climate and environment than either the Gobi or the Siberian taiga forests, and provides an ideal setting to test fundamental models of human biogeog- raphy in the context of regional population fluctuations. The area is presently occupied primarily by nomadic pastoralists, but it is clear that these complex middle Holocene (<6 ka) economic adaptations were not a necessary prerequisite for successful colonization of the high elevation Plateau. Exploratory field-work in 2000—2001 has established that Upper Paleolithic hunter-gatherers were present on the Qinghai-Tibetan Plateau by at least 12 ka and possibly much earlier. A speculative model for the colonization process is developed and preliminary archaeological data in support of the model are presented.

关键词：青藏高原晚更新世猎人聚集者定居时间自然环境人类地理学

An Accurate Cartesian Method for Incompressible Flows with Moving Boundaries

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Communications in Computational Physics 2014年第5期15卷 1266-1290页

作者： M.Bergmann j.Hovnanian A.Iollo Inria F-33400 TalenceFranceUniv.BordeauxIMBUMR 5251F-33400 TalenceFranceCNRSIMBUMR 5251F-33400 TalenceFrance.

An accurate cartesian method is devised to simulate incompressible viscous flows past an arbitrary moving *** Navier-Stokes equations are spatially discretized onto a fixed Cartesian *** body is taken into account via the ghost-cell method and the so-called penalty method,resulting in second-order accuracy in *** accuracy and the efficiency of the solver are tested through two-dimensional reference *** show the versatility of this scheme we simulate a threedimensional self propelled jellyfish prototype.

关键词： Viscous incompressible flow immersed boundary method penalty method cartesian grid self-propelled jellyfish.

Race, the microbiome and colorectal cancer

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World journal of Gastrointestinal Oncology 2019年第10期11卷 773-787页

作者： Kendra j Royston Babatunde Adedokun Olufunmilayo I Olopade Division of Hematology Oncology University of ChicagoChicagoIL 60637United States Center for Clinical Cancer Genetics and Global Health Department of Medicine University of ChicagoChicagoIL 60637United States

In the past decade,more cancer researchers have begun to understand the significance of cancer prevention,which has prompted a shift in the increasing body of scientific *** area of fascination and great potential is the human *** studies suggest that the gut microbiota has significant roles in an individual’s ability to avoid cancer,with considerable focus on the gut microbiome and colorectal *** in mind,racial disparities with regard to colorectal cancer treatment and prevention are generally understudied despite higher incidence and mortality rates among Non-Hispanic Blacks compared to other racial and ethnic groups in the United States.A comprehension of ethnic differences with relation to colorectal cancer,dietary habits and the microbiome is a meritorious area of *** review highlights literature that identifies and bridges the gap in understanding the role of the human microbiome in racial disparities across colorectal ***,we explore the differences in the gut microbiota,common short chain fatty acids produced in abundance by microbes,and their association with racial differences in cancer acquisition.

关键词： Diet Epigenetics Microbiome Disparities Colorectal Colon Cancer

Intestinal stem cells and the colorectal cancer microenvironment

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World journal of Gastroenterology 2014年第8期20卷 1898-1909页

作者： Bryan A Ong Kenneth j Vega Courtney W Houchen Department of Digestive Diseases University of Oklahoma Health Sciences CenterOklahoma CityOK 73104United States

Colorectal cancer (CRC) remains a highly fatal condition in part due to its resilience to treatment and its propensity to spread beyond the site of primary occurrence. One possible avenue for cancer to escape eradication is via stem-like cancer cells that, through phenotypic heterogeneity, are more resilient than other tumor constituents and are key contributors to cancer growth and metastasis. These proliferative tumor cells are theorized to possess many properties akin to normal intestinal stem cells. Not only do these CRC “stem” cells demonstrate similar restorative ability, they also share many cell pathways and surface markers in common, as well as respond to the same key niche stimuli. With the improvement of techniques for epithelial stem cell identification, our understanding of CRC behavior is also evolving. Emerging evidence about cellular plasticity and epithelial mesenchymal transition are shedding light onto metastatic CRC processes and are also challenging fundamental concepts about unidirectional epithelial proliferation. This review aims to reappraise evidence supporting the existence and behavior of CRC stem cells, their relationship to normal stem cells, and their possible dependence on the stem cell niche.

关键词： Colon cancer stem cells DCLK1 protein Stem cell niche Cell dedifferentiation

Application Prospect of Fission-Powered Spacecraft in Solar System Exploration Missions

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Space(Science & Technology) 2021年第1期2021卷 309-323页

作者： Y.Xia j.Li R.Zhai j.Wang B.Lin Q.Zhou Beijing Institute of Spacecraft Environment Engineering BeijingChina Science and Technology on Reliability and Environmental Engineering Laboratory BeijingChina Institute of Nuclear and New Energy Technology of Tsinghua University The Key Laboratory of Advanced Reactor Engineering and SafetyMinistry of EducationBeijingChina

Fission power is a promising technology,and it has been proposed for several future space *** is being considered for highpower missions whose goal is to explore the solar system and even *** fission power has made great progress when NASA’s 1 kWe Kilowatt Reactor Using Stirling TechnologY(KRUSTY)prototype completed a full power scale nuclear test in *** success stimulated a new round of research competition among the major space *** article reviews the development of the Kilopower reactor and the KRUSTY system *** summarizes the current missions that fission reactors are being considered as a power and/or propulsion *** projects include visiting jupiter and Saturn systems,Chiron,and Kuiper belt object;Neptune exploration missions;and lunar and Mars surface base *** studies suggest that the Fission Electric Propulsion(FEP)/Fission Power System(FPS)is better than the Radioisotope Electric Propulsion(REP)/Radioisotope Power System(RPS)in the aspect of cost for missions with a power level that reaches~1 kWe,and when the power levels reaches~8 kWe,it has the advantage of lower *** a mission that travels further than~Saturn,REP with plutonium may not be cost acceptable,leaving FEP the only *** missions prefer the use of FPS because it satisfies the power level of 10’s kWe,and FPS vastly widens the choice of possible landing *** to the current situation,we are expecting a flagship-level fission-powered space exploration mission in the next 1-2 decades.

关键词： satis Saturn isotope

Bioenergy Plants: Hopes,Concerns and Prospectives

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journal of Integrative Plant Biology 2011年第2期53卷 94-95页

作者： Martin A.j. Parry Hai-Chun jing Organizing Special Issue EditorRothamsted ResearchHarpenden Herts UK Organizing Special Issue EditorInstitute of BotanyChinese academy of SciencesBeijing China

There are major concerns over both the security of energy supplies （declining supplies and political control） and the en- vironmental costs associated with energy generation and use. The global consumption of carbon-containing fossil fuels for heat, electricity, transport and the manufacture of chemicals is not sustainable. This has promulgated a great interest in various forms of renewable energy and the imposition,

关键词： Bioenergy Plants Hopes,Concerns and Prospectives