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Gold as a Potential Contrast Agent for Dual-Energy CT

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Advances in Molecular Imaging 2013年第4期3卷 37-42页

作者： Radko Krissak Martin Elgert Bjorn Kusch ralph hünerbein Department of Diagnostic and Interventional Radiology Hufeland Klinikum GmbHBad LangensalzaGermany

Purpose: The K-edge of gold (81 keV) is located within the energy range of diagnostic CT. This might be advantageous for material differentiation in dual-energy CT (DECT). The aim of this in vitro study was to compare the differentiation between iodine or gold and body tissues using DECT at different kV spectra. Methods and Materials: A water filled tank phantom containing specimens with iodine (iopamidol), gold (sodium aurothiomalate), compact bone (compact porcine bone) and porcine muscle was scanned using a dual source CT (Definition, Siemens healthcare). Consecutive scans were performed at 80 kVp, 100 kVp, 120 kVp and 140 kVp with constant mAs settings. The mean attenuation values of the specimens were measured, and differences in calculated dual-energy ratios (DEratio) between body tissues and iodine or gold were determined for different DE spectra. Results: The attenuation of gold increased compared to 80 kVp at higher kVp-settings, while the attenuation of all other specimens decreased. The calculated DEratios at 80/100 kVp, 80/120 kVp and 80/140 kVp were 1.31, 1.62 and 1.91 for iodine, 0.89, 0.88 and 0.92 for gold, 1.20, 1.39 and 1.45 for compact bone, 1.01, 1.03 and 1.08 for muscle. The differences between the DEratios 80/100 kVp, 80/120 kVp and 80/140 kVp were 0.11, 0.23 and 0.46 for iodine and bone, 0.31, 0.51 and 0.53 for gold and bone, 0.29, 0.59 and 0.83 for iodine and muscle, 0.12, 0.15 and 0.16 for gold and muscle. Conclusion: DEratio of gold remains relatively stable along the energy spectrum of diagnostic CT and allows a reliable material differentiation between gold and bone already at contiguous low tube voltage settings (80 kV and 100 kV). Thus, gold might have a potential as a contrast agent for DECT.

关键词： Gold Computed Tomography Dual-Energy Contrast Agent K-Edge

Physical and geometrical parameters of CVBS X:the spectroscopic binary Gliese 762.1

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Research in Astronomy and Astrophysics 2016年第7期16卷 105-112页

作者： Suhail G.Masda Mashhoor A.Al-Wardat ralph Neuh user hamid M.Al-Naimiy Astrophysikalisches Institut und Universitats-Sternwarte Jena FSU Jena07745 JenaGermany Physics Department Faculty of ScienceAl al-Bayt UniversityPO Box:130040Mafraq25113 Jordan Applied Physics and Space Science Department University of Sharjah PO Box:27272 SharjahUnited Arab Emirates

We present the physical and geometrical parameters of the individual components of the close visual double-lined spectroscopic binary system Gliese 762.1, which were estimated using Al-Wardat＇s complex method for analyzing close visual binary systems. The estimated parameters of the individual components of the system are as follows： radius RA= 0.845±0.09R⊙, RB= 0.795±0.10R⊙, effective temperature Teff^A = 5300luminosity±50 K, Teff^B= 5150 L±50 K, surface gravity log gA= 4.52±0.10, log gB=4.54±0.15 and A= 0.51 with a semi-major axis of 0.0865±0.08L⊙, LB= 0.40±0.07L⊙. New orbital elements are presented±0.010 arcsec using the hippracos parallax π = 58.96 ndividual masses of the system are determined as M = 1.±0.65 mas, and an accurate total mass and i72±0.60 M⊙,MA= 0.89±0.08 M⊙and MB= 0.83 K0 V and±0.07 M⊙. Finally, the spectral types and luminosity classes of both components are assigned as K1.5V for the primary and secondary components respectively,and their positions on the h-R diagram and evolutionary tracks are given.

关键词： stars fundamental parameters binaries spectroscopic binary system atmospheres modeling Gliese 762 1

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Identification of Lignin and Polysaccharide Modifications in Populus Wood by Chemometric Analysis of 2D NMR Spectra from Dissolved Cell Walls

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Molecular Plant 2009年第5期2卷 933-942页

作者： Mattias hedenstrom Susanne Wiklund-Lindstrom Tommy Oman Fachuang Lu Lorenz Gerber Paul Schatz Bjorn Sundberg John ralph Department of Chemistry Umea University SE-90187 Umea Sweden Department of Biochemistry and Great Lakes Bioenergy Research Center University of Wisconsin Madison WI 53706 USA Umea Plant Science Centre Department of Forest Genetics and Plant Physiology Swedish University of Agricultural Sciences SE-90183 Umea Sweden US Dairy Forage Research Center USDA-Agricultural Research Service Madison WI 53706 USA

2D ^13C-^1h hSQC NMR spectroscopy of acetylated cell walls in solution gives a detailed fingerprint that can be used to assess the chemical composition of the complete wall without extensive degradation. We demonstrate how multivariate analysis of such spectra can be used to visualize cell wall changes between sample types as high-resolution 2D NMR loading spectra. Changes in composition and structure for both lignin and polysaccharides can subsequently be interpreted on a molecular level. The multivariate approach alleviates problems associated with peak picking of overlapping peaks, and it allows the deduction of the relative importance of each peak for sample discrimination. As a first proof of concept, we compare Populus tension wood to normal wood. All well established differences in cellulose, hemicellulose, and lignin compositions between these wood types were readily detected, confirming the reliability of the multivariate approach, In a second example, wood from transgenic Populus modified in their degree of pectin methylesterification was compared to that of wild-type trees. We show that differences in both lignin and polysaccharide composition that are difficult to detect with traditional spectral analysis and that could not be a priori predicted were revealed by the multivariate approach. 2D NMR of dissolved cell wall samples combined with multivariate analysis constitutes a novel approach in cell wall analysis and provides a new tool that will benefit cell wall research.

关键词： Aspen biostatistics cell walls multivariate data analysis NMR spectroscopy tension wood

Applied Optics to Engineering Photonics： a Retrospective

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Photonic Sensors 2011年第4期1卷 295-322页

作者： ralph P. TATAM Department of Engineering Photonics School of Engineering CranfieM University Cranfield Bedford MK43 OAL UK

This paper provides a short overview of the time I spent as a member of the Applied Optics Group at the University of Kent （1985-1989） followed by a review of my research during my time at Cranfield University （198... 详细信息

关键词： Optical fiber sensors optical instrumentation laser velocimetry speckle interferometry fiber Bragggratings long period fiber gratings optical gas sensing optical coherence tomography flow measurement coherentfiber optic bundles

Synovial Fluid Analysis

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Synovial Fluid Analysis

用简单的等熵面预报模式作短时预报和临近预报

中华医学会全国风湿病学年会

作者： h．ralph Schumacher Jr．Gilda Claybume Univeraity of Pennsylvania and VA Medical Center Philadelphia

INTRODUCTION Analysis of joint fluid should be performed as of the diagnostic evaluationin in any new patient with joint disease and an effusion and often at the time of in any unexpected change at a joint. Examination of joint fluid is expecially important in monarticular arthritis, in which septic arthritis must be distinguished from crystal disease and a wide variety of possible causes. Even small amounts of joint fluid can be aspirated and systematically examined.

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气象科技 1990年第2期18卷 27-33页

作者： ralph A. Petersen Jeffrey h. homan 王建中

1.引言在近十年中,数值预报模式已发展到能够准确地预报24小时以上的小尺度天气现象的水平和垂直结构.一个高分辨率的研究模式的试验结果表明预报对流事件甚至是中尺度α系统的技巧有了改进.在业务上,由区域性分析和预报系统(RAFS)得到... 详细信息

1.引言在近十年中,数值预报模式已发展到能够准确地预报24小时以上的小尺度天气现象的水平和垂直结构.一个高分辨率的研究模式的试验结果表明预报对流事件甚至是中尺度α系统的技巧有了改进.在业务上,由区域性分析和预报系统(RAFS)得到关于垂直运动和降水分布的预报差不多有3年了.不过,尽管观测资料中的小尺度现象对于预报重要的天气过程来说是重要的,但在分析和初值化的过程中经常被去掉或平滑掉.

关键词：短时预报预报模式天气过程初值化降水分布静力稳定度位涡垂直运动垂直结构尺度现象

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A PLIOCENE FLORA FROM ShANSI PROVINCE

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地质学报 1933年 142-158页

作者： ralph W.ChANEY University of Califomia Carnegie Institution of Washington

A small collection of fossil plants was made in 1930 by ***. Barbour,of Yenching University,in the course of his study of the sedimen-tary deposits near Taiku,Shansi Province (See text figure 1).My acknow-ledgement is... 详细信息

关键词： A PLIOCENE FLORA FROM ShANSI PROVINCE than

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关于痛风诊治决策的调查及相关因素分析

中华医学杂志 2006年第27期86卷 1901-1905页

作者：方卫纲曾学军李梦涛 Lan X Chen h ralph Schumacher Jr 张奉春中国医学科学院中国协和医科大学北京协和医院普通内科 100730 中国医学科学院中国协和医科大学北京协和医院风湿免疫科 100730 美国宾夕法尼亚大学风湿免疫科

目的了解国内医生诊治痛风的决策并对相关因素进行分析。方法对197名医生进行了关于痛风诊治决策的现场问卷调查,同时收集答卷人的个人资料,通过双变量分析和多重Logistic回归分析模型,分析影响决策的相关因素。结果一共收回120份有效... 详细信息

目的了解国内医生诊治痛风的决策并对相关因素进行分析。方法对197名医生进行了关于痛风诊治决策的现场问卷调查,同时收集答卷人的个人资料,通过双变量分析和多重Logistic回归分析模型,分析影响决策的相关因素。结果一共收回120份有效答卷。在诊断痛风时,94名医生(78．3％)认为应该检查患者的关节滑液。在治疗急性痛风发作时,如果患者肾功能良好,83名医生(69．2％)首选口服秋水仙碱;如果患者肾功能不全,50名医生(41．7％)首选皮质激素或促皮质激素。在降血尿酸治疗时,99名医生(82．5％)选择的指征不当,107名医生(89．2％)治疗开始得太早,92名医生(76．7％)用药的时间不够长。另外,在开始降血尿酸治疗的同时,仅有17名医生(14．2％)预防急性痛风的发作。多重Logistic回归分析发现痛风继续教育是医生采取正确诊断方法的相关因素。结论国内医生诊治痛风的决策与目前国际较为公认的意见并不一致,高质量的医学继续教育有可能提高医生诊治痛风的决策水平。

关键词：痛风决策问卷

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QT-GWAS:A novel method for unveiling biosynthetic loci affecting qualitative metabolic traits

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Molecular Plant 2023年第7期16卷 1212-1227页

作者： Marlies Brouckaert Meng Peng Renéhofer lias El houari Chiarina Darrah Veronique Storme Yvan Saeys Ruben Vanholme Geert Goeminne Vitaliy I.Timokhin John ralph Kris Morreel Wout Boerjan Ghent University Department of Plant Biotechnology and Bioinformatics9000 GhentBelgium VIB Center for Plant Systems Biology 9052 GhentBelgium Ghent University Department of Applied MathematicsComputer Science and Statistics9000 GhentBelgium VIB Center for Inflammation Research 9052 GhentBelgium vIB Metabolomics Core 9052 GhentBelgium Department of Biochemistry and US Department of Energy Great Lakes Bioenergy Research CenterWisconsin Energy InstituteUniversity of Wisconsin-MadisonMadisonWI53706USA Ghent University Department of Applied MathematicsComputer Science and StatisticsGhentBelgium ViB Center for Inflammation Research GhentBelgium BioNTech SE MainzRhineland-PalatinateGermany Eunomia Research&Consulting BristolUK VIB Agro-incubator NeveleBelgium Research Institute for Chromatography KortrijkBelgium

Although the plant kingdom provides an enormous diversity of metabolites with potentially beneficial applications for humankind,a large fraction of these metabolites and their biosynthetic pathways remain *** metabolite structures and their biosynthetic pathways is key to gaining biological understanding andto allow metabolic *** orderto retrieve novel biosynthetic genes involved in specialized metabolism,we developed a novel untargeted method designated as qualitative trait GWAs(QT-GWAS)that subjects qualitative metabolic traits to a genome-wide association study,while the conventional metabolite GWAS(mGWAS)mainly considers the quantitative variation of *** a proof of the validity of QT-GWAS,23 and 15of the retrieved associations identified in Arabidopsis thaliana by QTGWAS and mGWAS,respectively,were supported by previous ***,seven genemetabolite associations retrieved by QT-GWAS were confirmed in this study through reverse genetics combined with metabolomics and/or in vitro enzyme *** such,we established that CYTOChROME P450706A5(CYP706A5)is involved in the biosynthesis of chroman derivatives,UDP-GLYCOSYLTRANSFERASE 76C3(UGT76C3)is able tohexosylate guanine in vitro and in planta,and SULFOTRANSFERASE 202B1(SULT202B1)catalyzes the sulfation of neolignans in ***,our study demonstrates that the untargeted QT-GWAS method can retrieve valid gene-metabolite associations at the level of enzyme-encoding genes,even new associations that cannot be found by the conventional mGwAs,providing a new approach for dissecting qualitative metabolic traits.

关键词： qualitative method proof