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Predicting gas and shrinkage porosity in solidification microstructure:A coupled three-dimensional cellular automaton model

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Journal of Materials Science & Technology 2020年第14期47卷 91-105页

作者： Cheng Gu colin D.Ridgeway Emre Cinkilic Yan Lu Alan A.Luo Department of Materials Science and Engineering The Ohio State UniversityColumbusOH 43210USA Department of Integrated Systems Engineering The Ohio State UniversityColumbusOH 43210USA

Porosity formation during solidification of aluminum-based alloys,due to hydrogen gas and alloy shrinkage,has been a major issue adversely affecting the performance of solidification products such as castings,welds or additively manufactured components.A three-dimensional cellular automaton(CA)model has been developed,for the first time,to couple the predictions of hydrogen-induced gas porosity and shrinkage porosity during solidification microstructure evolution of a binary Al-Si *** CA simulation results are validated under various cooling rates by porosity measurements in an experimental wedge die casting using X-ray micro computed tomography(XMCT)*** validated porosity moel provides a critical link in integrated computation materials engineering(ICME)design and manufacturing of solidification products.

关键词： Solidification Cellular automaton Microstructure simulation Microporosity evolution

Heterogeneity in agricultural households and transition paths in southern Tibet

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Journal of Mountain Science 2022年第5期19卷 1386-1403页

作者： ZHANG Jing BROWN colin WALDRON Scott YADAV Lava ZHUOGA De-qing School of Agriculture and Food Sciences The University of QueenslandBrisbane 4072Australia Research Institute of Animal Husbandry and Veterinary Medicine Tibet Academy of Agricultural and Animal Husbandry SciencesLhasa 850002China

Smallholder livelihoods in agricultural areas in Tibet Autonomous Region,China(Tibet for short)have traditionally been based on subsistence mixed crop-livestock *** many parts of China and the developing world,rural Tibet is undergoing rapid change in agricultural development,boosted by links with the off-farm ***,the agricultural transition process in Tibet has not been linear,is affected by policies particular to the region,and varies significantly for different categories of rural *** paper analyses heterogeneity of household types in agricultural areas of southern Tibet and how household structures and characteristics result in different agricultural development *** is drawn from a stratified random survey of 144 households in three townships in southern Tibet and analysed through three methods:cluster analysis,bio-economic modelling,and analysis of household perceptions and attitudes to *** analysis allows for the identification of three key household types-semisubsistence,pluriactive and semi-commercial-organised along a continuum of intensification,commercialisation,specialisation and *** study demonstrates the diversity of household farming systems in Tibet which in turn highlights the need for disaggregated analysis and tailored development policies and ***,the analysis also reveals commonalities in development paths between groups,where all farm types are more interested in pursuing income and livelihood goals through an increase in productivity than through an increase in *** in all systems choose to retain agriculture as a base from which to pursue livelihood strategies,especially through off-farm *** for this household heterogeneity is important on several ***,it provides more granular detail on the process of development in rural areas of Tibet that have been very difficult to access in English literature especially in recent ***,the c

关键词： Tibet Households Farming systems Agricultural transition

严寒地区典型城市公共建筑节能改造技术适用性分析

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建设科技 2024年第17期 24-28,34页

作者：刘景东马文生李鹏毛杰刘超杨诗薇中国建筑科学研究院有限公司北京100013 建科环能科技有限公司北京100013 郑州公共住宅建设投资有限公司郑州450003

本文分析严寒地区公共建筑节能改造技术适用性,以典型城市为例,分析了供暖、照明、可再生能源、节水及监测控制等节能改造技术效果。结果表明,供暖系统改造节能效果显著,照明系统改造节能率高且经济性好,可再生能源利用具有潜力,节水改... 详细信息

本文分析严寒地区公共建筑节能改造技术适用性,以典型城市为例,分析了供暖、照明、可再生能源、节水及监测控制等节能改造技术效果。结果表明,供暖系统改造节能效果显著,照明系统改造节能率高且经济性好,可再生能源利用具有潜力,节水改造和监测控制系统也有效提升了节能效果,综合节能率超过15%,实现显著节能减排效益。可为严寒地区公共建筑节能改造技术应用推广提供借鉴,为城乡建设领域“碳达峰”公共建筑提升提供技术路径参考。

关键词：公共建筑节能改造碳达峰严寒地区

A quasi-crystal model of collagen microstructure based on SHG microscopy

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Chinese Optics Letters 2010年第2期8卷 213-216页

作者： Pu Xu Eleanor Kable colin J. R. Sheppard Guy Cox Australian Key Centre for Microscopy and MicroanMysis University of Sydney NSW 2006 Australia Division of Bioengineering National University of Singapore Singapore 117576 Key Laboratory of Ecophysics Department of Physics Shihezi University Shihezi 832000 China

Second harmonic generation （SHG） results from molecules which are polarized by an external electric field often provided by an intense laser beam. The polarizability depends on firstly the intrinsic structural properties of the substance and hence the second-order nonlinear susceptibility, and secondly the intensity and polarization direction of the incident light. The polarization characteristics of the beam are therefore of interest. In this letter, we discuss some considerations in SHG microscopy of collagen when the incoming beam is circularly polarized, and present some supporting results as well as a numerical analysis. We propose a quasi-crystal model of collagen microstructure in an effort to further our understanding on this protein.

关键词： Collagen Electric fields Harmonic generation Nonlinear optics Numerical analysis Polarization Quasicrystals

Assessment of contrast sensitivity loss after intrastromal femtosecond laser and LASIK procedure

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International Journal of Ophthalmology(English edition) 2016年第12期9卷 1798-1801页

作者： Elsa L.C.Mai ie-Bin Lian David C.K.Chang Far Eastern Memorial Hospital Taipei 100 Taiwan China National Changhua University of Education Changhua 500Taiwan China Taiwan Nobel Eye Institute Taipei 100 Taiwan China

AIM： To assess the loss of contrast sensitivity （CS） function for INTRACOR or intrastromal femtosecond laser presbyopia procedure to conventional LASIK ***： Patients were recruited from a refractive surgery center for either INTRACOR or conventional LASIK. INTRACOR was performed on 8 eyes and LASIK was performed for 40 eyes in an overlapping period. Pre-operative evaluation and post-operative follow up for up to three months was done. Drops of CS in 4 spatial frequency （3 cpd, 6 cpd, 12 cpd and 18 cpd） right before and 3mo after the surgery were compared by Wilcoxon signed ranks ***： For INTRACOR, CS threshold showed significant drop at both glare and non-glare condition, the drop was seen in all 4 spatial frequency. The averaged loss over the 4 spatial frequencies 3mo after surgery was 1.18 for non-glare and 0.71 for glare. For LASIK the CS threshold drop was most significant in 12 cpd for ***： INTRACOR procedure produces a gain of near vision for presbyopia patients but also introduces a high lost of contrast sensitivity plus worsen of vision quality. Pre-surgical patient selection and advise should be given with specific regards to night driving and glare conditions.

关键词： INTRACOR LASIK contrast sensitivity intrastromal femtosecond laser

The role of mRNA splicing in prostate cancer

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Asian Journal of Andrology 2014年第4期16卷 515-521页

作者： Anna V Lapuk Stanislav V Volik Yuzhuo Wang colin C Collins Vancouver Prostate CentreUniversity of British Columbia Vancouver BC Canada. Department of Experimental Therapeutics BC Cancer AgencyUniversity of British Columbia Vancouver BC Canada. Department of Urologic Sciences University of British Columbia Vancouver BC Canada.

Alternative splicing （AS） is a crucial step in gene expression. It is subject to intricate regulation, and its deregulation in cancer can lead to a wide array of neoplastic phenotypes. A large body of evidence implicates splice isoforms in most if not all hallmarks of cancer, including growth, apoptosis, invasion and metastasis, angiogenesis, and metabolism. AS has important clinical implications since it can be manipulated therapeutically to treat cancer and represents a mechanism of resistance to therapy. In prostate cancer （PCa） AS also plays a prominent role and this review will summarize the current knowledge of alternatively spliced genes with important functional consequences. We will highlight accumulating evidence on AS of the components of the two critical pathways in PCa： androgen receptor （AR） and phosphoinositide 3-kinase （PI3K）. These observations together with data on dysregulation of splice factors in PCa suggest that AR and PI3K pathways may be interconnected with previously unappreciated splicing regulatory networks. In addition, we will discuss several lines of evidence implicating splicing regulation in the development of the castration resistance.

关键词： alternative splicing prostate cancer androgen receptor PI3K pathway CRPC neuroendocrine transdifferentiation REST repressor complex

Novel susceptibility genes in inflammatory bowel disease

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World Journal of Gastroenterology 2006年第13期12卷 1991-1999页

作者： colin Noble Elaine Nimmo Daniel Gaya Richard K Russell Jack Satsangi Gastrointestinal Unit Molecular Medicine Centre University of EdinburghWestern General HospitalEdinburghUnited Kingdom

The inflammatory bowel disease, Crohn's disease and ulcerative colitis, are polygenic disorders with important environmental interactions. To date, the most widely adopted approach to identifying susceptibility genes in complex diseases has involved genome wide linkage studies followed by studies of positional candidate genes in loci of interest. This review encompasses data from studies into novel candidate genes implicated in the pathogenesis of inflammatory bowel disease. Novel techniques to identify candidate genes-genome wide association studies, yeast-two hybrid screening, microarray gene expression studies and proteomic profiling, are also reviewed and their potential role in unravelling the pathogenesis of inflammatory bowel disease are discussed.

关键词： Inflammatory bowel disease Crohn's disease Ulcerative colitis Yeast-two hybrid Genomics

In an interconnected world: joint research priorities for the environment, agriculture and infectious disease

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Infectious Diseases of Poverty 2014年第1期3卷 15-17页

作者： Bianca Brijnath colin D Butler Anthony J McMichael Department of General Practice School of Primary Health CareMonash UniversityBuilding 1270 Ferntree Gully RoadNotting HillVictoria 3168Australia Faculty of Health University of CanberraCanberraAustralia National Centre for Epidemiology and Population Health Australian National UniversityCanberraAustralia

In 2008 the UNICEF/UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases(TDR)commissioned ten think-tanks to work on disease-specific and thematic reference groups to identify top research priorities that would advance the research agenda on infectious diseases of poverty,thus contributing to improvements in human *** first of the thematic reference group reports-on environment,agriculture and infectious diseases of poverty-was recently *** this article we review,from an insider perspective,the strengths and weaknesses of this thematic reference group report and highlight key messages for policy-makers,funders and researchers.

关键词： Agriculture Environment Infectious disease Research priorities TDR

Swimming behavior of juvenile silver carp near the separation zone of a channel confluence

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International Journal of Sediment Research 2022年第1期37卷 122-127页

作者： Saiyu Yuan Lei Xu Hongwu Tang Yang Xiao colin Whittaker State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Yangtze Institute for Conservation and Development Department of Civil and Environmental Engineering The University of Auckland

Knowledge of locomotion of fish near river confluences is important for prediction of fish distribution in a river *** flow separation zone near the confluence of a river network is a favorite habitat and feeding place for silver carp,which is one of the four major species of Chinese carp and usually provides positive rheotaxis to water *** the current study,a series of laboratory experiments were done to determine the behavioral responses of juvenile silver carp to the hydrodynamic forces near the separation zone of a channel *** locomotion and trajectory of juvenile silver carp were recorded by infrared thermal imaging,while the flow velocity field near the separation zone was measured by a Particle Image Velocimetry (PIV) system.A total of 60 juvenile silver carp were released near the separation zone among which 40 carp swam in the upstream *** them,24 carp swam to the tributary and the remaining 16 swam into the main *** all these 24 carp travelled initially along the boundary of the separation zone near the corner,where flow shear was strongest,and then swam to the *** of avoiding zones of strong vorticity,they chose and followed a trajectory along which the flow vorticity was *** encountering these vortical flows,they increased the tailbeat frequency and decreased the tail-beat amplitude to maintain body *** observations provide important knowledge on locomotion of fish near river confluences and are beneficial for the fish habitat protection.

关键词： Channel confluence Flow separation Juvenile silver carp Fish locomotion