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Segmentation of Images from Fourier Spectral Data

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Communications in Computational Physics 2009年第2期5卷 326-349页

作者： anne Gelb Dennis Cates Department of Mathematics and Statistics Arizona State UniversityTempeArizona 85287 USA

This paper designs a segmentation method for an image based on its Fourier spectral *** edge map is generated directly from the Fourier coefficients without first reconstructing the image in pixelated *** the internal boundaries of the edge map are not blurred by any(filtered)Fourier *** edge map is then processed with an edge linking segmentation *** include examples from magnetic resonance imaging(MRI).Our results illustrate some potential benefits of using high order methods in imaging.

关键词： Fourier coefficients edge detection segmentation

Xerotolerant foliar endophytic fungi of Populus euphratica from the Tarim River basin,Central China are conspecific to endophytic ITS phylotypes of Populus tremula from temperate Europe

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Fungal Diversity 2012年第3期54卷 133-142页

作者： Martin Unterseher anne Petzold Martin Schnittler Institute of Botany and Landscape Ecology Department of Systematic BotanyErnst-Moritz-Arndt UniversityGrimmer Str.8817487 GreifswaldGermany

Fungal research on non-lichenized taxa in xeric and other unusual habitats for fungi is comparatively scarce but constantly reveal an enormous ecological and functional adaptiveness of these organisms to *** holds true in the topmost forest canopies as well as in marine,arctic,antarctic or desert *** the present study dried leaves of Populus euphratica from a continental desert area in Central China were investigated for endophytic fungi 6 weeks after sampling by cultivation of small leaf ***-five species,many of them well-known from extreme environments,were delimitated from as few as 58 isolates by a combined analysis of morphotypes,micromorphology and ITS ***-analyses revealed pronounced conspecificity to endophytes from Populus tremula leaves,but significant differences to foliar endophytic assemblages in Pinus monticola and Fagus *** deduced high similarity of endophytic communities on both Populus species compared with that on Pinus and Fagus suggests that many fungal phyllosphere species show a well-pronounced host preference,at least for their endophytic *** addition,it demonstrates that leaving leaves as a microhabitat might provide similar conditions such as constantly high relative humidity,regardless of the surrounding climatic *** evolution of extremotolerance might be of particular importance for retaining competitiveness of foliar endophytes in deciduous host trees after loss of pathogenicity.

关键词： Frost-drought tolerance Extremophile Alternaria Cladosporium Penicillium Evolution of endophytism

Reproductive Immunology Issue One： Cellular and Molecular Biology

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Cellular & Molecular Immunology 2014年第5期11卷 405-406页

作者： Guest Editor B anne Croy Department of Biomedical and Molecular Sciences Queen's University Kingston ON Canada

It is estimated that immune system evolution commenced more than 600 million years ago （Mya） when ancestral forms of MHC and CD45 appeared establishing innate immunity. By 500 Mya, RAG gene evolution had occurred, founding adaptive *** first mammals appeared much later （220 Mya） and reproduced by laying of eggs. Placental mammals with internal gestations and live born offspring have existed for only 100 Mya, with humans and mice being relatively recent mam- malian evolutions.

关键词： IMMUNE INNATE CELLS

Reproductive Immunology Issue 2： Cellular and Molecular Biology

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Cellular & Molecular Immunology 2014年第6期11卷 503-505页

作者： Guest Editor B anne Croy Department of Biomedical and Molecular Sciences Queen's University Kingston ON Canada

In Issue 1 of this special topic series on Reproductive hnmunology （September 2014 issue of Cellular and MolecMar Immunology, Vol. 11, No. 5）, immune cell populations in the reproductive tracts of males and non-pregnant females were discussed. Emphasis was placed on endocrine regulation of the specialized cells that populate these mucosal tissues.

关键词： Reproductive Immunology Issue Cellular and Molecular

Potential risk factors for constipation in the community

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World Journal of Gastroenterology 2021年第21期27卷 2795-2817页

作者： Barry L Werth Sybele-anne Christopher Susan Wakil School of Nursing and Midwifery Faculty of Medicine and HealthUniversity of SydneySydney 2006New South WalesAustralia

Constipation is a common community health *** are many factors that are widely thought to be associated with constipation but real-world evidence of these associations is difficult to *** potential risk factors may be categorised as demographic,lifestyle and health-related *** review presents the available evidence for each factor by an assessment of quantitative data from cross-sectional studies of community-dwelling adults published over the last 30 *** appears that there is evidence of an association between constipation and female gender,residential location,physical activity and some health-related factors such as self-rated health,some surgery,certain medical conditions and certain *** available evidence for most other factors is either conflicting or ***,further research is necessary to determine if each factor is truly associated with constipation and whether it can be regarded as a potential risk *** is recommended that studies investigating a broad range of factors are conducted in populations in community *** analyses should be performed to account for all possible confounding *** this way,valuable evidence can be accumulated for a better understanding of potential risk factors for constipation in the community.

关键词： Adults Constipation Epidemiology Factors Community

ACCURATE AND EFFICIENT IMAGE RECONSTRUCTION FROM MULTIPLE MEASUREMENTS OF FOURIER SAMPLES

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Journal of Computational Mathematics 2020年第5期38卷 797-826页

作者： T.Scarnati anne Gelb Air Force Research Laboratory WPAFBOH 45433USA Dartmouth College HanoverNH 03755USA

Several problems in imaging acquire multiple measurement vectors(MMVs)of Fourier samples for the same underlying *** recovery techniques from MMVs aim to exploit the joint sparsity across the measurements in the sparse *** is typically accomplished by extending the use of`1 regularization of the sparse domain in the single measurement vector(SMV)case to using`2,1 regularization so that the“jointness”can be accounted *** effective,the approach is inherently coupled and therefore computationally *** method also does not consider current approaches in the SMV case that use spatially varying weighted`1 regularization *** recently introduced variance based joint sparsity(VBJS)recovery method uses the variance across the measurements in the sparse domain to produce a weighted MMV method that is more accurate and more efficient than the standard`2,1 *** efficiency is due to the decoupling of the measurement vectors,with the increased accuracy resulting from the spatially varying *** by these results,this paper introduces a new technique to even further reduce computational cost by eliminating the requirement to first approximate the underlying image in order to construct the *** this preprocessing step moreover reduces the amount of information lost from the data,so that our method is more *** examples provided in the paper verify these benefits.

关键词： Multiple measurement vectors Joint sparsity Weighted`1 Edge detection Fourier data

Macrophage polarization in nerve injury： do Schwann cells play a role？

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Neural Regeneration Research 2016年第1期11卷 53-57页

作者： Jo anne Stratton Prajay T.Shah Department of Clinical Neurosciences University of Calgary Calgary Canada Hotchkiss Brain Institute Calgary Canada Department of Comparative Biology and Experimental Medicine University of Calgary Calgary Canada

In response to peripheral nerve injury, the inflammatory response is almost entirely comprised of infiltrating macrophages. Macrophages are a highly plastic, heterogenic immune cell, playing an indispensable role in peripheral nerve injury, clearing debris and regulating the microenvironment to allow for efficient regeneration. There are several cells within the microenvironment that likely interact with macrophages to support their function – most notably the Schwann cell, the glial cell of the peripheral nervous system. Schwann cells express several ligands that are known to interact with receptors expressed by macrophages, yet the effects of Schwann cells in regulating macrophage phenotype remains largely unexplored. This review discusses macrophages in peripheral nerve injury and how Schwann cells may regulate their behavior.

关键词： nerve macrophage traumatic injury Schwann cells polarization

Evolutionary consequences of deception： Complexity and informational content of colony signature are favored by social parasitism

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Current Zoology 2014年第1期60卷 137-148页

作者： Maria Cristina LORENZI Laura AZZANI anne-Genevieve BAGNRRES Department of Life Sciences and Systems Biology University of Turin via Accademia Albertina 13 10123 Torino Italy I.R.B.I. - UMR CNRS 7261 - Universit6 de Tours Facult6 des Sciences Parc Grandmont 37200 Tours France

Nestmate recognition codes show remarkable chemical complexity, involving multiple biochemical pathways. This complexity provides the opportunity to evaluate the ecological and social conditions that favor the evolution of complex signaling. We investigated how the chemical signatures of three populations of the social paper wasp Polistes biglumis differed in terms of concentration of hydrocarbons, proportions of branched hydrocarbons and overall variation. We tested whether the variation in chemical signatures among populations could be explained by the prevalence of social parasites or whether this was just an effect of local abiotic conditions which influenced the composition of the hydrocarbon cuticular layer. We studied the chemical signa- ture in three populations in which obligate social parasites differed in the selection pressures they imposed on host populations. Within each population, we restricted our analyses to non-parasitized hosts, to avoid potential short-term effects of parasite pres- ence on the host chemical signatures. We found that host colonies in parasitized populations had more diverse profiles than the parasite-free population. Moreover, the overall concentration of hydrocarbons and the relative proportion of branched hydrocar- bons were larger in the parasitized populations, relative to the non-parasitized one. This is to our knowledge the first evidence in favour of the hypothesis that different traits in the host chemical signatures as a whole undergo evolutionary changes resulting from directional or balancing selection imposed by social parasites. We conclude that obligate social parasites act as ＇engines of diversity＇ on host chemical signatures and operate in favor of a geographic mosaic of diverging communication codes

关键词： Polistes Brood parasitism Cipher Nestmate recognition Hydrocarbons Geographic mosaic Crozier's paradox

Wetting of pure aluminium on graphite,SiC and Al_2O_3 in aluminium filtration

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Transactions of Nonferrous Metals Society of China 2012年第8期22卷 1930-1938页

作者：包萨日娜唐恺 anne KVITHYLD Thorvald ENGH Merete TANGSTAD Department of Materials Science and Engineering Norwegian University of Science and TechnologyNO-7491TrondheimNorway SINTEF Materials and Chemistry NO-7465TrondheimNorway

The wettability of pure aluminium on filter materials and on inclusions is believed to be an important factor affecting the filtration of aluminium. The contact angles of molten aluminium on alumina, SiC and graphite were measured under 10-8 bar high vacuum in the temperature range of 1000-1300 °C. To describe the wetting behaviour of the Al on ceramic at lower temperatures used in filtration and casting aluminium, a semi-empirical calculation was employed. The calculated contact angles at 700 °C were around 97° for alumina, 92° for vitreous graphite, 126° for single- and poly-crystal graphite, and 79° for single crystal SiC, respectively. This indicates that aluminium does not wet alumina or graphite （or Al4C3） around the casting temperature, but wets SiC at this temperature. Thus a priming height is required for aluminium to infiltrate an alumina filter. Increasing temperature can also improve the wettability of Al on ceramic.

关键词： wettability contact angle aluminium alumina SiC graphite