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铁路、人口流动与城市化——略论美国西部开发模式

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城市规划汇刊 2001年第6期 70-74页

作者：王磊伍新木 michael latham 武汉大学美国Fordham大学

对于落后区域的开发过程 ,由于在其初期阶段必然存在着市场失灵 ,因此政府所承担的基础设施建设 ,是实现其发展的第一推动力。然后 ,一些必需的物质要素 ,如人口 ,才会逐渐流向该区域 ,从而使区域内的城市得到迅速的增长 ,并以此带动整... 详细信息

对于落后区域的开发过程 ,由于在其初期阶段必然存在着市场失灵 ,因此政府所承担的基础设施建设 ,是实现其发展的第一推动力。然后 ,一些必需的物质要素 ,如人口 ,才会逐渐流向该区域 ,从而使区域内的城市得到迅速的增长 ,并以此带动整个地区的城市化进程。这个普遍性的规律对于任何国家而言都是适用的。本文以此为线索 ,考察了美国历史上的西部开发过程 ,并与中国的西部开发进行了比较。

关键词：铁路人口流动美国城市化西部开发模式

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蛔虫病和钩虫病对人类营养的威胁

中国学校卫生 1991年第1期12卷 17-18页

作者： michael.C.latham 李锡明胡小原美国康奈尔大学营养学系

目前全世界有20亿以上的人受到寄生虫感染。在发展中国家,特别是在热带和亚热带地区,这种感染非常普遍,以蛔虫最多。估计有12亿人感染蛔虫,约占世界人口的1/4。钩虫有美洲钩虫和十二指肠钩虫两种主要类型,约有8亿人受此感染。但这种情... 详细信息

目前全世界有20亿以上的人受到寄生虫感染。在发展中国家,特别是在热带和亚热带地区,这种感染非常普遍,以蛔虫最多。估计有12亿人感染蛔虫,约占世界人口的1/4。钩虫有美洲钩虫和十二指肠钩虫两种主要类型,约有8亿人受此感染。但这种情况一直没有得到各国卫生部门以及国际卫生组织的足够重视。

关键词：蛔虫病钩虫病营养

A three-dimensional feature extraction-based method for coal cleat characterization using X-ray μCT and its application to a Bowen Basin coal specimen

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 153-166页

作者： Yulai Zhang Matthew Tsang Mark Knackstedt michael Turner Shane latham Euan Macaulay Rhys Pitchers ARC Training Centre for M3D Innovation Research School of PhysicsAustralian National UniversityCanberraACT2601Australia Department of Materials Physics Research School of PhysicsAustralian National UniversityCanberraACT2601Australia Anglo American Steelmaking Coal BrisbaneQLD4000Australia SCT Operations Pty Ltd. WollongongNSW2500Australia

Cleats are the dominant micro-fracture network controlling the macro-mechanical behavior of *** understanding of the spatial characteristics of cleat networks is therefore important to the coal mining *** fracture networks(DFNs)are increasingly used in engineering analyses to spatially model fractures at various *** reliability of coal DFNs largely depends on the confidence in the input cleat *** of these parameters can be made from image-based three-dimensional(3D)characterization of coal cleats using X-ray micro-computed tomography(m CT).One key step in this process,after cleat extraction,is the separation of individual cleats,without which the cleats are a connected network and statistics for different cleat sets cannot be *** this paper,a feature extraction-based image processing method is introduced to identify and separate distinct cleat groups from 3D X-ray m CT ***(filters)representing explicit cleat features of coal are built and cleat separation is successfully achieved by convolutional operations on 3D coal *** new method is applied to a coal specimen with 80 mm in diameter and 100 mm in length acquired from an Anglo American Steelmaking Coal mine in the Bowen Basin,Queensland,*** is demonstrated that the new method produces reliable cleat separation capable of defining individual cleats and preserving 3D topology after ***-parallel fractures are also identified and separated,which has his-torically been challenging to delineate and rarely reported.A variety of cleat/fracture statistics is measured which not only can quantitatively characterize the cleat/fracture system but also can be used for DFN ***,variability and heterogeneity with respect to the core axis are *** heterogeneity is observed and suggests that the representative elementary volume(REV)of the cleat groups for engineering purposes may be a complex problem requ

关键词： Cleat separation Cleat statistics Feature extraction Discrete fracture network(DFN)modeling

Influence of inter-grain cementation stiffness on the effective elastic properties of porous Bentheim sandstone

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第3期15卷 573-583页

作者： Bin Chen Jiansheng Xiang John-Paul latham Department of Earth Science and Engineering Faculty of EngineeringImperial College LondonLondonSW72BXUK

Effective elastic properties of porous media are known to be significantly influenced by *** this paper,we investigated the influence of another critical factor,the inter-grain cementation stiffness,on the effective elastic properties of a granular porous rock(Bentheim sandstone)using an advanced numerical workflow with realistic rock microstructure and a theoretical ***,the disparity between the experimentally tested elastic properties of Bentheim sandstone and the effective elastic properties predicted by empirical equations was ***,a micro-computed tomography(CT)-scan based approach was implemented with digital imaging software AVIZO to construct the 3D(three-dimensional)realistic microstructure of Bentheim *** microstructural model was imported to a mechanics solver based on the 3D finite element model with inter-grain boundaries modelled by cohesive *** simulations were run to test the effective elastic properties for different shear and normal intergrain cementation ***,a relation between the macroscale Young’s modulus and inter-grain cementation stiffness was derived with a theoretical model which can also account for porosity *** the numerical and theoretical results indicate the influence of the inter-grain cementation stiffness,on the effective elastic properties is significant for porous *** calibrated normal and shear stiffnesses at the inter-grain boundaries are 1.2×10^(5) and 4×10^(4) GPa/m,respectively.

关键词： Porous sandstone Cohesive finite element model Grain-based model Rock microstructure Micro-computed tomography(CT)

Molecular determinants for the layering and coarsening of biological condensates

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Aggregate

Aggregate 2022年第6期3卷 113-121页

作者： Andrew P.latham Bin Zhang Department of Chemistry Massachusetts Institute of TechnologyCambridgeMassachusettsUSA Department of Bioengineering and Therapeutic Sciences University of California at San FranciscoSan FranciscoCaliforniaUSA

Many membraneless organelles,or biological condensates,form through phase separation,and play key roles in signal sensing and transcriptional *** the functional importance of these condensates has inspired many studies to characterize their stability and spatial organization,the underlying principles that dictate these emergent properties are still being *** this review,we examine recent work on biological condensates,especially multicomponent *** focus on connecting molecular factors such as binding energy,valency,and stoichiometry with the interfacial tension,explaining the nontrivial interior organization in many *** further discuss mechanisms that arrest condensate coalescence by lowering the surface tension or introducing kinetic barriers to stabilize the multidroplet state.

关键词： biological condensate intrinsically disordered protein membraneless organelle phase separation surface tension

DNA recovery and analysis from skeletal material in modern forensic contexts

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Forensic Sciences Research 2019年第1期4卷 51-59页

作者： Krista E.latham Jessica J.Miller Biology Department Human Identification CenterUniversity of IndianapolisIndianapolisINUSA

The generation of a DNA profile from skeletal remains is an important part of the identifica-tion process in both mass disaster and unidentified person cases. Since bones and teeth are often the only biological materials remaining after exposure to environmental conditions, intense heat, certain traumatic events and in cases where a significant amount of time has passed since the death of the individual, the ability to purify large quantities of informative DNA from these hard tissues would be beneficial. Since sampling the hard tissues for gen-etic analysis is a destructive process, it is important to understand those environmental and intrinsic factors that contribute to DNA preservation. This will serve as a brief introduction to these topics, since skeletal sampling strategies and molecular taphonomy have been dis-cussed in depth elsewhere. Additionally advances in skeletal DNA extraction and analysis will be discussed. Currently there is great variation in the DNA isolation methods used by laboratories to purify DNA from the hard tissues;however, a standardized set of short tan-dem repeat (STR) loci is analyzed by many US laboratories to allow for comparisons across samples and jurisdictions. Recent advances have allowed for the generation of DNA profiles from smaller quantities of template DNA and have expanded the number of loci analyzed for greater discriminatory power and predictions regarding the geographic ancestry and phenotype of the individual. Finally, utilizing databases and expanding the number of com-parison samples will be discussed in light of their role in the identification process.

关键词： Forensic sciences forensic anthropology forensic genetics individual identification molecular taphonomy skeletal DNA Extraction DNA profiles DNA databases

latham法和牙龈——骨膜成形术治疗婴儿唇腭裂的初期评价

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华西口腔医学杂志 1991年第4期9卷 272-275页

作者：徐慧芬 Dr.Ralph latham Dr.Ralph Millard 华西医科大学口腔颌面外科学教研室加拿大西安大略大学美国迈阿密大学再造整形外科中心

简介了 latham 法和牙龈-骨膜成型术对唇腭裂婴儿的治疗及意义。观察测定了接受该治疗的44例唇腭裂患儿的咬合关系和牙槽裂区新骨形成的状况。结果发现:44例唇腭裂中,15例前牙反(牙合)。27例咬合片中有63%在齿槽裂区有不同程度的新骨生... 详细信息

简介了 latham 法和牙龈-骨膜成型术对唇腭裂婴儿的治疗及意义。观察测定了接受该治疗的44例唇腭裂患儿的咬合关系和牙槽裂区新骨形成的状况。结果发现:44例唇腭裂中,15例前牙反(牙合)。27例咬合片中有63%在齿槽裂区有不同程度的新骨生长。对该结果作了初期的评价,并提出了一些改进意见。

关键词： latham法唇裂腭裂骨形成

Technology　Encounters　China＇s　People　and　Culture：　The　United　Technologies　Corporation

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China Today 1995年第9期44卷 30-34页

作者： RICHARD latham

ＴｅｃｈｎｏｌｏｇｙＥｎｃｏｕｎｔｅｒｓＣｈｉｎａ＇ｓＰｅｏｐｌｅａｎｄＣｕｌｔｕｒｅ：ＴｈｅＵｎｉｔｅｄＴｅｃｈｎｏｌｏｇｉｅｓＣｏｒｐｏｒａｔｉｏｎＢｙＲＩＣＨＡＲＤＬＡＴＨＡＭＴＨＥＵｎｉｔｅｄＴｅｃｈｎｏｌｏ... 详细信息

ＴｅｃｈｎｏｌｏｇｙＥｎｃｏｕｎｔｅｒｓＣｈｉｎａ＇ｓＰｅｏｐｌｅａｎｄＣｕｌｔｕｒｅ：ＴｈｅＵｎｉｔｅｄＴｅｃｈｎｏｌｏｇｉｅｓＣｏｒｐｏｒａｔｉｏｎＢｙＲＩＣＨＡＲＤＬＡＴＨＡＭＴＨＥＵｎｉｔｅｄＴｅｃｈｎｏｌｏｇｉｅｓＣｏｒｐｏｒａｔｉｏｎ（Ｕ...

关键词： China

The Virtual Geoscience Workbench, VGW: Open Source tools for discontinuous systems

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Particuology 2010年第2期8卷 100-105页

作者： A. Munjiza J. Xiang X. Garcia J.P. latham G.G. Schiava D'Albano N.W.M. John Department of Engineering Queen Mary London University London UK Department of Earth Science and Engineering Imperial College London UK

In 1989 work began on merging finite and discrete elements. During 1990 algorithmic solutions for the new combined method were developed, together with a C-based implementation known as the Y code. In 2004 these developments and implementations were published as a textbook. Queen Mary University of London ~QMUL） and Imperial College are currently engaged in a research project to make Y codes in both 2D and 3D available in Open Source format and with mainly geoscience problems in mind. The result is a set of Open Source tools for Geoscience （VGW）, key components of which are summarised in this paper, together with illustrative range of simulation results. 2009 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

关键词： Combined finite-discrete elementWorkbenchModellingGeoscience