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Re-evaluation of the phylogenetic position of the genus Dexiotrichides (Protozoa, Ciliophora, scuticociliatida) inferred from stomatogenetic and molecular information for Dexiotrichides pangi

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Progress in Natural science:Materials International 2005年第8期15卷 700-707页

作者： alan WARREN,David ROBERTs,Norbert WILBERT London sW7 5BD UK Zoologisches Institut Universitt Bonn 53115 Bonn Germany Department of Zoology Natural History of Museum Cromwell Road London sW7 5BD UK Department of Zoology Natural History of Museum Cromwell Road

The divisional process and systematic position of the marine scuticociliate Dexiotrichides pangi are studied. Based on both stomatogenetic data and 18s rDNA gene sequences, the phylogeny and morphogenetic characteristics of this taxon, and of other related genera, are analyzed and discussed. Both the divisionary events and the molecular biological data indicate that this species/genus, together with certain other genera in the Dexiotricha-complex, occupies an intermediate position between the tetrahymenids and the “typical” scuticociliate, which suggests that the Dexiotricha-like taxa should be excluded from the “true” scuticociliates. As a further contribution, the process of stomatogenesis in D. pangi can be summarized as follows: (1) The oral primordia in the opisthe are formed only by the proliferation of basal bodies in the scutica field, which subsequently develop into three membranelles, while the new paroral membrane seems to be generated by the sub-anterior portion of somatic kinety 1 (the 1st postoral intercalary kinety). The latter character exhibits a mode similar to Tetrahymena. (2) In the proter the parental membranelles are retained and remain unchanged throughout the entire division process; only the old paroral membrane is disassembled and differentiated into the anlage, which then gives rise to the new paroral membrane and the scutica of the proter. The 18s rRNA gene sequence reported here is the first one for a ciliate in the Dexiotricha-complex.

关键词： marine ciliate systematic position stomatogenesis 18s rRNA gene sequences Dexiotrichides pangi.

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Tolerance of disturbance by humans in long-time resident and recent colonist urban doves

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Chinese Birds 2015年第2期6卷 113-120页

作者： Jemma Gendall alan Lill Juliey Beckman Wildlife Ecology and Conservation Physiology School of Biological SciencesMonash University Clayton Campus school of Life sciences La Trobe University College of Medicine Biology and Environment Australian National University

Background: A critical trait for successful urban dwelling by birds is the ability to tolerate high levels of disturbing stimulation by humans. If such tolerance is partly acquired gradually after colonization, species with a long history of residence in cities are likely to be more tolerant of such stimulation than recent urban colonists, but this has not often been ***: We tested whether introduced Rock(Columba livia) and spotted(streptopelis chinensis) Doves, historically long-term residents of Melbourne, Australia, were more tolerant of disturbance by humans than the very recent colonist, the native Crested Pigeon(Ochyphaps lophotes) by comparing the Flight Initiation Distances(FID) and time allocations to vigilance during foraging of all three species in urban Melbourne. That all three species are members of the Columbiformes reduces the possibility that any species differences in tolerance are simply phylogenetic in ***: Flight initiation distance was shorter in Rock Doves than in the other two species, which did not differ in approachability by a human. Rock Doves retreated from an approaching human mainly by walking a relatively short distance, Crested Pigeons mainly by running a relatively short distance and spotted Doves primarily by flying a comparatively long distance. The time allocation to anti-predator vigilance of Rock Doves was smaller than that of the other two species, whose allocations were ***: The very recent colonist of eastern Melbourne, the Crested Pigeon, was not the least tolerant of disturbance by humans of the three related species. Natural selection for tolerance therefore probably cannot entirely explain the pattern of tolerance evident among these urban dove species and behavioural flexibility is probably involved. Length of residency in a city is not an infallible guide to a species' level of tolerance of disturbance by humans.

关键词： Doves Urban environment Flight initiation distance Vigilance Behavioural flexibility

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Macroscopic analysis of time dependent plasticity in Ti alloys

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Journal of Materials science & Technology 2022年第29期124卷 135-140页

作者： Yi Xiong Phani s.Karamched Chi-Toan Nguyen David M.collins Christopher M.Magazzeni Edmund Tarleton Angus J.Wilkinson Department of Materials University of OxfordParks RoadOxford OX13PHUnited Kingdom Department of Materials and Processes Safran SASafran TechMany-les-Hameaux 78772France school of Metallurgy and Materials University of BirminghamEdgbastonBirmingham B152TTUnited Kingdom Department of Engineering science University of OxfordParks RoadOxford OX13PJUnited Kingdom

Cold dwell fatigue is the critical technological issue in Ti alloys used in the cooler front sections of aerospace jet *** subjected to a sustained load(stress dwell),the lifetime of these Ti components can be drastically reduced by as much as an order of magnitude[1–4].Without a clear understanding of the effect,safety concerns are raised.

关键词： alloys fatigue lifetime

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Constitutive behavior and processing maps of a new wrought magnesium alloy ZE20 (Mg-2Zn-0.2Ce)

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Journal of Magnesium and Alloys 2020年第1期8卷 111-126页

作者： scott C.sutton alan A.Luo Department of Materials science and Engineering The Ohio State UniversityColumbusOH 43210United States Department of Integrated systems Engineering The Ohio State UniversityColumbusOH 43210United States Mag specialties Inc. DenverCO 80210USA

ZE20(Mg-2Zn-0.2Ce)^2 is a new wrought magnesium alloy with improved extrudability and mechanical properties[1].To understand the constitutive behavior and workability of this new alloy,Gleeble thermomechanical testing has been carried out in this *** flow stress behavior of ZE20 was investigated between 250℃–450℃ and 10^–3 s^–1–1.0 s^–1 in isothermal *** descriptions of the flow stress are provided.A new general approach at application of the extended Ludwik equation is demonstrated and was found to be more accurate than the hyperbolic sine Arrhenius model while having a similar number of model *** maps were developed based on the experimental results and are verified with microstructural investigation.A region of safe processing with non-basal texture and high activity of dynamic recrystallization(DRX)was found between 375℃ and 450℃,from 10^–1 s^–1 to 10^–2.5 s^–1.A region of potentially safe processing with annealing that is associated with shear band nucleation of non-basal grains was identified for temperatures as low as 300℃ and rates as high as 10^–1 s^–1.

关键词： Magnesium alloys Thermomechanical processing Constitutive behavior Processing map Deformation mechanisms

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Numerical simulation of blood flow and interstitial fluid pressure in solid tumor microcirculation based on tumor-induced angiogenesis

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Acta Mechanica sinica 2007年第5期23卷 477-483页

作者： Gaiping Zhao Jie Wu shixiong Xu M. W. collins Quan Long Carola s. Konig Yuping Jiang Jian Wang A. R. Padhani Department of Mechanics and Engineering science Fudan University Shanghai 200433 China Brunel Institute for Bioengineering School of Engineering and Design Brunel University Uxbridge Middlesex UK Department of Neurology Huashan Hospital Fudan University Shanghai 200040 China Paul strickland scanner Centre Mount Vernon Hospital Rickmansworth Road Northwood Middlesex HA6 2RN UK

A coupled intravascular-transvascular-interstitial fluid flow model is developed to study the distributions of blood flow and interstitial fluid pressure in solid tumor microcirculation based on a tumor-induced microvascular network. This is generated from a 2D nine-point discrete mathematical model of tumor angiogenesis and contains two parent vessels. Blood flow through the microvascular network and interstitial fluid flow in tumor tissues are performed by the extended Poiseuille＇s law and Darcy＇s law, respectively, transvascular flow is described by starling＇s law; effects of the vascular permeability and the interstitial hydraulic conductivity are also considered. The simulation results predict the heterogeneous blood supply, interstitial hypertension and low convection on the inside of the tumor, which are consistent with physiological observed facts. These results may provide beneficial information for anti-angiogenesis treatment of tumor and further clinical research.

关键词： solid tumor pressure-Angiogenesis Blood flow - Interstitial Numerical simulation

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Next Generation Transcriptome sequencing and Quantitative Real-Time PCR Technologies for Characterisation of the Bemisia tabaci Asia 1 mtCOI Phylogenetic Clade

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Journal of Integrative Agriculture 2012年第2期11卷 281-292页

作者： susan seal Mitulkumar V Patel Carl collins John Colvin David Bailey Natural Resources Institute University of GreenwichChatham Maritime Kent ME4 4TBUnited Kingdom

A programme of functional genomics research is underway at the University of Greenwich,UK,to develop and apply genomics technologies to characterise an economically-important but under-researched Bemisia tabaci（Hemiptera：Aleyrodidae）,the Asia 1 mtCOI phylogenetic group.A comparison of this putative species from India with other important *** populations and insect species may provide targets for the development of more effective whitefly control *** a first step,next-generation sequencing（NGs）has been used to survey the transcriptome of adult female whitefly,with high quality RNA preparations being used to generate cDNA libraries for NGs using the Roche 454 Titanium DNA sequencing *** assemblies constructed from the resultant sequences（301 094 reads）using the software program CLC Genomics Workbench generated 3 821 core *** of a selection of these contigs with related sequences from other *** genetic groups has revealed good alignment for some genes（e.g.,HsP90）but misassemblies in other datasets（e.g.,the vitellogenin gene family）,highlighting the need for manual curation as well as collaborative international efforts to obtain accurate assemblies from the existing next generation sequence ***,data emerging from the NGs has facilitated the development of accurate and reliable methods for analysing gene expression based on quantitative real-time RT-PCR,illustrating the power of this approach to enable rapid expression analyses in an organism for which a complete genome sequence is currently lacking.

关键词： Bemisia tabaci whitefly transcriptome next generation sequencing quantitative real-time (QRT)-PCR Asia 1 mtCOI

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新墨西哥州sOR中间层钠层结构的季节和夜间变化

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地球物理学报 2003年第3期46卷 304-308页

作者：胡雄 Chester s.Gardner alan Liu 中国科学院武汉物理与数学研究所武汉430071 Department of Electrical Computer Engineering

利用 1998年 1月至 2 0 0 0年 5月美国新墨西哥州starfireOpticRange (sOR :35°N ,10 6 .5°W)钠风场、温度激光雷达共 46个观测夜的数据 ,分析大气中间层钠层结构的季节变化特征 .结果表明 ,钠层丰度变化显示出很强的年振荡现象 ,其... 详细信息

利用 1998年 1月至 2 0 0 0年 5月美国新墨西哥州starfireOpticRange (sOR :35°N ,10 6 .5°W)钠风场、温度激光雷达共 46个观测夜的数据 ,分析大气中间层钠层结构的季节变化特征 .结果表明 ,钠层丰度变化显示出很强的年振荡现象 ,其平均值为 5 .0 6× 10 9cm- 2 ,最大值出现在 11月份 ,最小值出现在 6月和 7月份 .钠层均方根宽度的平均值为 4.30km ,中心高度的平均值为 91.6 0km .均方根宽度和中心高度变化显示出较明显的半年振荡特征 .年平均钠层夜间变化显示出潮汐的影响 ,丰度夜间变化在午夜前最小 ,日出前达到最大 .白天光离化作用和夜间复合过程 ,与潮汐动力学一起 ,导致钠层丰度发生较大的夜间变化 .

关键词：钠层结构钠激光雷达季节变化流星中层大气动力学化学示踪物

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Improvement on the inversion of kernel-driven BRDF model

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Chinese science Bulletin 1999年第1期44卷 76-79页

作者： alan H.strahler Department of Geography and Centre for Remote sensing Boston University Boston USA

Kernel-driven model was chosen to calculate global albedo in the project of multiangular remote sensor MODIs. The best kernels were selected by the venerable 'least square' method. The result of this method was very unstable when only a small amount of angular observations is available. A new criterion has been estalished, called 'least variance' for the kernel’s selection. It takes into consideration the effects of model and measurement based on the information inverse theory. several tests showed that 'least variance' has many advantages. First, it is less sensitive to noises. second, it operates well in small sample size. Third, it depends less on the sampling position.

关键词： multiangular remote sensing BRDF model inversion global albedo.

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Is age just a number: pancreaticoduodenectomy in elderly patients?

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Hepatobiliary & Pancreatic Diseases International 2016年第4期15卷 346-347页

作者： Vikas Dudeja alan Livingstone Division of surgical Oncology De Witt Daughtry Family Department of SurgeryUniversity of Miami Miller School of Medicine

Pancreatic cancer incidence is increasing *** the developed countries have seen a greater increase in the age-standardized incidence rate of pancreatic cancer（29%from 1990-2013）,developing countries are also not spa... 详细信息

关键词： standardized elderly incidence safely mortality Whipple morbidity malignancy postoperative curative

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An information theory perspective on computational vision

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Frontiers of Electrical and Electronic Engineering in China 2010年第3期5卷 329-346页

作者： alan YUILLE Department of statistics University of California at Los AngelesLos AngelesCA 90095USA

This paper introduces computer vision from an information theory *** discuss how vision can be thought of as a decoding problem where the goal is to find the most efficient encoding of the visual *** requires probabilistic models which are capable of capturing the complexity and ambiguities of natural *** start by describing classic Markov Random Field(MRF)models of *** stress the importance of having efficient inference and learning algorithms for these models and emphasize those approaches which use concepts from information *** we introduce more powerful image models that have recently been developed and which are better able to deal with the complexities of natural *** models use stochastic grammars and hierarchical *** are trained using images from increasingly large ***,we described how techniques from information theory can be used to analyze vision models and measure the effectiveness of different visual cues.

关键词： computer vision pattern recognition information theory minimum description length Markov random field(MRF)model stochastic grammars

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