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Genetic epidemiology of primary sclerosing cholangitis

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World Journal of Gastroenterology 2007年第41期13卷 5421-5431页

作者： tom H Karlsen Erik Schrumpf Kirsten Muri Boberg Medical Department Rikshospitalet-Radiumhospitalet Medical CenterOsloNorway

The aetiology of primary sclerosing cholangitis (PSC) is not known. A more than 80-fold increased risk of PSC among first-degree relatives emphasizes the importance of genetic factors. Genetic associations within the human leukocyte antigen (HLA) complex on chromosome 6p21 were detected in PSC 25 years ago. Subsequent studies have substantiated beyond doubt that one or more genetic variants located within this genetic region are important. The true identities of these variants,however,remain to be identified. Several candidate genes at other chromosomal loci have also been investigated. However,according to strict criteria for what may be denominated a susceptibility gene in complex diseases,no such gene exists for PSC today. This review summarises present knowledge on the genetic susceptibility to PSC,as well as genetic associations with disease progression and clinical subsets of particular interest (inflammatory bowel disease and cholangiocarcinoma).

关键词： Primary sclerosing cholangitis Genetic associations Human leukocyte antigens Cholangiocarcinoma Inflammatory bowel disease

Effects of a phase transition on two-pion interferometry in heavy ion collisions at √SNN=2.4-7.7 GeV

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Science China(Physics,Mechanics & Astronomy) 2023年第3期66卷 88-97页

作者： Pengcheng Li Jan Steinheimer tom Reichert Apiwit Kittiratpattana Marcus Bleicher Qingfeng Li Institut fur Theoretische Physik Johann Wolfgang Goethe Universitat FrankfurtFrankfurt am Main 60438Germany School of Science Huzhou UniversityHuzhou 313000China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China Frankfurt Institute for Advanced Studies Frankfurt am Main 60438Germany GSI Helmholtzzentrum f¨urSchwerionenforschung GmbH Darmstadt 64291Germany Helmholtz Research Academy Hesse for FAIR(HFHF) GSI Helmholtz Center for Heavy Ion PhysicsCampus FrankfurtFrankfurt am Main 60438Germany Center of Excellence in High Energy Physics&Astrophysics School of PhysicsSuranaree University of TechnologyNakhon Ratchasima 30000Thailand

Hanbury-Brown-Twiss(HBT) correlations for charged pions in central Au+Au collisions at √SNN=2.4-7.7 GeV(corresponding to beam kinetic energies in the fixed target frame from Elab=1.23 to 30 GeV/nucleon) are calculated using the ultra-relativistic quantum molecular dynamics model with different equations of state(EoSs).The effects of a phase transition at high baryon densities are clearly observed in the explored HBT *** results show that the available data on the HBT radii,RO/RSand R^(2)_(O)-R^(2)_(S),in the investigated energy region favor a relatively stiff EoS at low beam energies,which then turns into a soft EoS at high collision energies consistent with astrophysical constraints on the high-density EoS of quantum chromodynamics(QCD).The specific effects of two different phase transition scenarios on RO/RSand R^(2)_(O)-R^(2)_(S)are investigated.A phase transition with a significant softening of the EoS below four times the nuclear saturation density can be excluded using HBT *** results highlight that the pion’s RO/RSand R^(2)_(O)-R^(2)_(S)are sensitive to the stiffness of the EoS and can be used to constrain and understand the QCD EoS in a high baryon density region.

关键词： heavy ion collisions HBT correlation equation of state

The effect of host plants on genotype variability in fitness and honeydew composition of Aphis fabae

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Insect Science 2017年第5期24卷 781-788页

作者： Sharon Schillewaert Amelie Vantaux Wim Van den Ende tom Wenseleers Laboratory of Socioecology and Social Evolution Biology Department Zoological Institute University of Leuven Leuven Belgium Institut Pasteur du Cambodge Unite d'Epidemiologie Moleculaire du Paludisme Phnom Penh Cambodia Laboratory of Molecular Plant Biology Biology Department University of Leuven Leuven Belgium

Aphid species can be polyphagous, feeding on multiple host plants across genera. As host plant species can have large variation in their phloem composition, this can affect aphid fitness and honeydew composition. Previous research showed significant intraspecific genotype variation in the composition of the honeydew carbohydrates of the black bean aphid Aphis fabae, with the ant attractant trisaccharide melezitose showing especially large variation across different genotypes. In this study, we test if variation in melezitose and carbohydrate composition of aphid honeydew could be linked to the adap- tation of specific aphid genotypes to particular host plants. To this end, 4 high and 5 low melezitose secreting genotypes of the black bean aphid Aphisfabae were reared on 4 com- mon host plants： broad bean, goosefoot, beet, and poppy. The carbohydrate composition, and in particular melezitose secretion, showed important aphid genotype and host plant in- teractions, with some genotypes being high melezitose secreting on 1 host plant but not on another. However, the interaction effects were not paralleled in the fitness measurements, even though there were significant differences in the average fitness across the different host plants. On the whole, this study demonstrates that aphid honeydew composition is influenced by complex herbivore-plant interactions. We discuss the relevance of these findings in the context of ant-aphid mutualisms and adaptive specialization in aphids.

关键词： aphids Aphis fabae ecological specialization fitness honeydew hostplants Melezitose polyphagous

Experimental-computational study of fibrous particle transport and deposition in a bifurcating lung model

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Particuology 2016年第5期14卷 102-113页

作者： Xiaole Chen Wenqi Zhong Josin tom Clement Kleinstreuer Yu Feng Xiaopu He Key Laboratory of Energy Thermal Conversion and Control of the Ministry of Education School of Energy and Environment Southeast University Nanjing210096 China Department of Mechanical and Aerospace Engineering North Carolina State University Raleigh NC 27695 USA Department of Biomedical Engineering North Carolina State University Raleigh NC27695 USA School of Chemical Engineering Oklahoma State University Stillwater OK 74078 USA First Affiliated Hospital of Nanjing Medical University Nanjing 210029 China

Experiments carried out using a lung model with a single horizontal bifurcation under different steady inhalation conditions explored the orientation of depositing carbon fibers, and particle deposition frac- tions. The orientations of deposited fibers were obtained from micrographs. Specifically, the effects of the sedimentation parameter （γ）, fiber length, and flow rate on orientations were analyzed. Our results indicate that gravitational effect on deposition cannot be neglected for 0.0228 〈 γ 〈 0.247. The absolute orientation angle of depositing fibers decreased linearly with increasing y for values 0.0228 〈 γ 〈 0.15. Correspondence between Stokes numbers and y suggests these characteristics can be used to estimate fiber deposition in the lower airways. Computer simulations with sphere-equivalent diameter models for the fibers explored deposition efficiency vs. Stokes number. Using the volume-equivalent diameter model, our experimental data for the horizontal bifurcation were replicated. Results for particle deposition using a lung model with a vertical bifurcation indicate that body position also affects deposition.

关键词： Lung aerosol dynamics Image-processing method Fiber deposition data Computer simulations Deposited fiber orientations

The hyperpycnite problem: comment

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Journal of Palaeogeography 2019年第3期8卷 314-320页

作者： A.J.(tom) van Loon Heiko Hüneke Thierry Mulder Geocom Consulting Valle del Portet 17 03726 Benitachell Spain College of Earth Science and Engineering Shandong University of Science and Technology Qingdao 266590 Shandong China Institute of Geography and Geology Greifswald University Greifswald Germany UMR CNRS EPOC University of Bordeaux Allee Geoffroy St-Hilaire 33615 Pessac Cedex France

A recent review article("The hyperpycnite problem") by Shanmugam(Journal of Palaeogeography 7(3):197–238,2018) in this journal has some shortcomings, comes to scientifically incorrect conclusions, and calls for student education in a way that would significantly diminish the students’ changes for a geological career. Having studied--and still studying--hyperpycnites in the field, it seems only appropriate to inform the readers of this journal about our concerns regarding the review article mentioned ***, the article by Shanmugam(Journal of Palaeogeography 7(3):197–238, 2018) is not a review paper but rather a comment, criticizing al researchers who have come to the conclusion, on the basis of both field research and theory,that hyperpycnal flows result in sediments(hyperpycnites) with characteristics that make it possible to distinguish them from deposits formed in another way. This is also the essence of Shanmugam’s comment: as he states himself, he is"an ardent critic of al genetic facies models".

关键词： review Shanmugam critic

Stochastic collocation for device-level variability analysis in integrated photonics

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Photonics Research 2016年第2期4卷 93-100页

作者： Yufei Xing Domenico Spina Ang Li tom Dhaene Wim Bogaerts Photonics Research Group Department of Information Technology Center for Nano and BiophotonicsGhent University imec Department of Information Technology Internet Based Communication Networks and Services (IBCN)Ghent University iMinds Luceda Photonics

We demonstrate the use of stochastic collocation to assess the performance of photonic devices under the effect of uncertainty. This approach combines high accuracy and efficiency in analyzing device variability with the ease of implementation of sampling-based methods. Its flexibility makes it suitable to be applied to a large range of photonic devices. We compare the stochastic collocation method with a Monte Carlo technique on a numerical analysis of the variability in silicon directional couplers.

关键词： Stochastic collocation for device-level variability analysis in integrated photonics

FORCE RIPPLE SUPPRESSION TECHNOLOGY FOR LINEAR MOTORS BASED ON BACK PROPAGATION NEURAL NETWORK

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Chinese Journal of Mechanical Engineering 2008年第2期21卷 13-16页

作者： ZHANG Dailin CHEN Youping AI Wu ZHOU Zude KONG Ching tom School of Mechanical Engineering Huazhong University of Science and Technology Wuhan 430074 China Institute of Precision EngTneering The Chinese University of Hong Kong Hong Kong China

Various force disturbances influence the thrust force of linear motors when a linear motor （LM） is running. Among all of force disturbances, the force ripple is the dominant while a linear motor runs in low speed. In order to suppress the force ripple, back propagation（BP） neural network is proposed to learn the function of the force ripple of linear motors, and the acquisition method of training samples is proposed based on a disturbance observer. An off-line BP neural network is used mainly because of its high running efficiency and the real-time requirement of the servo control system of a linear motor. By using the function, the force ripple is on-line compensated according to the position of the LM. The experimental results show that the force ripple is effectively suppressed by the compensation of the BP neural network.

关键词： Linear motor (LM) Back propagation(BP) algorithm Neural network Anti-disturbance technology

JES Special issue in Mercury Biogeochemistry and Fate

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Journal of Environmental Sciences 2018年第6期30卷 1-4页

作者： tom Sizmur Nelson O'Driscoll Yong Cai

The global and regional redistribution of mercury within the environment is of primary importance to both natural ecosystems and human *** ratification of the Minamata Convention on Mercury by 91 parties represents a ... 详细信息

关键词： JES Special issue in Mercury Biogeochemistry and Fate Hg

Synthesis And Property of Low Loaded Pt Alloy Catalysts for Oxygen Reduction

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Synthesis And Property of Low Loaded Pt Alloy Catalysts for ...

作者： tom ROBERT 上海交通大学

学位级别：硕士

最近,燃料电池作为一种新能源,由于具有能够解决当前世界传统能源不足以及环境问题的潜能,越来越引起科研工作者的重视。燃料电池目前已被广泛应用于电动汽车和工厂的应急发电。时至今日,科学家们研制出了多种类型的燃料电池,比如质子... 详细信息

最近,燃料电池作为一种新能源,由于具有能够解决当前世界传统能源不足以及环境问题的潜能,越来越引起科研工作者的重视。燃料电池目前已被广泛应用于电动汽车和工厂的应急发电。时至今日,科学家们研制出了多种类型的燃料电池,比如质子交换膜燃料电池(PEFMC),直接甲醇燃料电池(DFMC)、磷酸燃料电池(PAFC)等等。然而作为新能源,目前燃料电池的成本依然居高不下,特别是因为采用的铂商业催化剂电极占到了成本的一大部分。为了解决这个问题,研究者们做出了很多尝试,但是鲜有低铂含量的催化剂材料。在本文中,基于溶剂热法,我们设计了一种简易且高效的合成低铂含量催化剂(Pt质量比低于10%)的方法。同时,我们分析了不同反应条件下(反应物、络合剂或者溶剂)的产物的形貌、性能的变化。同时我们研究了不同合金形貌的合成,比如八面体状、空心机构以及二维结构。我们对不同形貌的产物以及商业催化剂Pt进行了电化学测试分析(比如循环伏安扫描测试和线性伏安扫描),然后比较它们的电化学性能。结果表明,虽然性能低于商业催化剂,但是由于铂含量极低以及新型特殊的结构,为以后优化和提高这类催化剂的性能提供了基础。

关键词：燃料电池溶剂热法 Figure 扫描测试能源不足 octahedral 交换膜 catalysis hollow 化学性能