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在浅海沉积层的垂直反射地震图上测定Q值方法的比较

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地球物理学进展 1986年第2期 75-87页

作者： D.jannsen j.voss F.Theilen 严寿民

对于测定浅海沉积层Q值的四种方法进行了比较:两种传统的方法,即上升时间法和频谱比法,两种新方法,即频谱模拟法和子波模拟法。而子波模拟法能同时测定Q值和反射时间T,比从地震图上读取反射时间T准确得多。上升时间法和频谱比法用于直... 详细信息

对于测定浅海沉积层Q值的四种方法进行了比较:两种传统的方法,即上升时间法和频谱比法,两种新方法,即频谱模拟法和子波模拟法。而子波模拟法能同时测定Q值和反射时间T,比从地震图上读取反射时间T准确得多。上升时间法和频谱比法用于直接从资料得出Q值,两种模拟方法的原理是根据参考子波或它的频谱,对于不同的Q值来计算吸收效应和频散效应,实测资料与计算资料符合最好的就是最佳结果。用合成资料的数字检验表明:对于包含有噪音或叠加波至的资料,其精度很少有能够超过25％的;因此在任何情况下,子波模拟法是较好的方法,利用波罗的海一个垂直反射剖面的资料得出不同层的0值在15—100之间,这与本地区的沉积环境相符合。

关键词：子波模拟上升时间模拟法频谱比法多次反射波多次波反射地震波至反射层地层地震图地质图频散关系振幅谱脉冲振动的复变谱波谱分析噪音噪声语音沉积层

Current Injection Provokes Rapid Expansion of the Guard Cell Cytosolic Volume and Triggers Ca^2＋ Signals

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Molecular Plant 2016年第3期9卷 471-480页

作者： Lena j. voss Rainer Hedrich M. Rob G. Roelfsema Molecular Plant Physiology and Biophysics Julius-von-Sachs Institute for Biosciences Biocenter Werzburg University Julius-von-Sachs-Platz 2 97082 Werzburg Germany

High-resolution microscopy opens the door for detailed single-cell studies with fluorescent reporter dyes and proteins. We used a confocal spinning disc microscope to monitor fluorescent dyes and the fluorescent protein Venus in tobacco and Arabidopsis guard cells. Multi-barreled microelectrodes were used to inject dyes and apply voltage pulses, which provoke transient rises in the cytosolic Ca^2＋ level. Voltage pulses also caused changes in the distribution of Lucifer Yellow and Venus, which pointed to a reversible increase of guard cell cytosolic volume. The dynamic cytosolic volume changes turned out to be provoked by current injection of ions. A reduction of the clamp current, by blocking K^＋ uptake channels with Cs^＋, strongly suppressed the cytosolic volume changes. Cs^＋ not only inhibited the expansion of the cytosol, but also inhibited hyperpolarization-induced elevations of the cytosolic Ca^2＋ concentration. A complete loss of voltage-induced Ca^2＋ signals occurred when Ca^2＋-permeable plasma membrane channels were simultaneously blocked with La^3＋. This shows that two mechanisms cause hyperpolarization-induced elevation of the cytosolic Ca^2＋-concentration：（i） activation of voltage-dependent Ca^2＋-permeable channels, （ii） osmotically induced expansion of the cytosol, which leads to a release of Ca^2＋ from intracellular stores.

关键词： guard cell cytosolic Ca^2+ cytosolic volume voltage clamp current injection ion channel

Deletion of a Stay-Green Gene Associates with Adaptive Selection in Brassica napus

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Molecular Plant 2016年第12期9卷 1559-1569页

作者： Lunwen Qian Kai voss-Fels Yixin Cui Habib U. jan Birgit Samans Christian Obermeier Wei Qian Rod j. Snowdon Department of Plant Breeding IFZ Research Centre for Biosystems Land Use and Nutrition Justus Liebig University Heinrich-Buff-Ring 26-32 35392 Giessen Germany College of Agronomy and Biotechnology Southwest University 400716 Chongqing China

Chlorophyll levels provide important imrormation about plant growth and physiological plasticity in response to changing environments. The stay-green gene NON-YELLOWING 1 （NYE1） is believed to regu-late chlorophyll degradation during senescence, concomitantly affecting the disassembly of the light- harvesting complex and hence indirectly influencing photosynthesis. We identified Brassica napus acces- sions carrying an NYE1 deletion associated with increased chlorophyll content, and with upregulated expression of light-harvesting complex and photosynthetic reaction center （PSI and PSII） genes. Compar- ative analysis of the seed oil content of accessions with related genetic backgrounds revealed that the B. napus NYE1 gene deletion （bnnyel） affected oil accumulation, and linkage disequilibrium signatures suggested that the locus has been subject to artificial selection by breeding in oilseed B. napus forms. Comparative analysis of haplotype diversity groups （haplogroups） between three different ecotypes of the allopolyploid B. napus and its A-subgenome diploid progenitor, Brassica rapa, indicated that introgres- sion of the bnnyel deletion from Asian B. rapa into winter-type B. napus may have simultaneously improved its adaptation to cooler environments experienced by autumn-sown rapeseed.

关键词： rapeseed breeding chlorophyll photosynthesis presence-absence variation PAV

Atlas of the human brain 3rd ed

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2008年

作者： jürgen K. Mai, George Paxinos, Thomas voss

ISBN: (纸本)9780123736031

High resolution human imaging requires a high resolution atlas. There is no atlas that approaches the accuracy and comprehensiveness of The Atlas of the Human Brain . This is the third, thoroughly revised, edition of the very successful atlas that received the Award of Excellence from the American Association of Publishers. Constructed by the recognized leaders in brain cartography, the atlas pro

关键词： Neurosciences.BrainAtlases.BrainAnatomyAtlases.NeuroanatomyAtlases.Brain.

来源：畅想之星图书光盘版（南... 评论

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马早期妊娠诊断方法之比较

草食家畜 1986年第2期 16-17页

作者： j.L.voss 郭成华

迄今,通过直肠触摸生殖道仍是母马妊娠诊断最常用的方法。最近已建立了超声波探查法和检测马绒毛膜促性腺激素(eCG)的免疫学方法。由马子宫内膜杯分泌的eCG,在妊娠35—40天出现在外周血液中,65—70天达峰值,120天后消失。检测eCG的方法... 详细信息

迄今,通过直肠触摸生殖道仍是母马妊娠诊断最常用的方法。最近已建立了超声波探查法和检测马绒毛膜促性腺激素(eCG)的免疫学方法。由马子宫内膜杯分泌的eCG,在妊娠35—40天出现在外周血液中,65—70天达峰值,120天后消失。检测eCG的方法有生物学测定法、血凝抑制试验(HIA)、放射免疫测定法、直接乳胶凝集法(DLA)、受体分析法和酶联免疫吸附法(ELISA)

关键词：早期妊娠母马超声波探查妊娠诊断诊断方法

Assessing Density Functionals for Describing Methane Dissociative Chemisorption on Pt(110)-(2×1)Surface

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Chinese journal of Chemical Physics 2021年第6期34卷 883-895,I0004页

作者： Fenfei Wei Egidius W.F.Smeets johannes voss Geert-jan Kroes Sen Lin Hua Guo State Key Laboratory of Photocatalysis on Energy and Environment College of ChemistryFuzhou UniversityFuzhou 350002China Leiden University Leiden Institute of ChemistryEinsteinweg 552333 CCLeidenThe Netherlands SUNCAT Center for Interface Science and Catalysis SLAC National Accelerator Laboratory2575 Sand Hill RoadMenlo Park CA 94025USA Department of Chemistry and Chemical Biology University of New MexicoAlbuquerqueNew Mexico 87131USA

In this work,we explore the suitability of several density functionals with the generalized gradient approximation(GGA)and beyond for describing the dissociative chemisorption of methane on the reconstructed Pt(110)-(2×1)*** bulk and surface structures of the metal,methane adsorption energy,and dissociation barrier are used to assess the functionals.A van der Waals corrected GGA functional(optPBE-vdW)and a metaGGA functional with van der Waals correction(MS PBEl-rVV10)are selected for ab initio molecular dynamics calculations of the sticking *** results suggest that the use of these two functionals may lead to a better agreement with existing experimental results,thus serving as a good starting point for future development of reliable machine-learned potential energy surfaces for the dissociation of methane on the Pt(110)-(2×1)surface.

关键词： Functionals Methane Dissociation Pt(110)-(2×1)

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禽淋巴白血病病毒感染诊断中的可能性和限制

广西畜牧兽医 2009年第2期25卷 81-82页

作者： Matthias voss 苗得园韦平德国Lohmann Tierzucht公司北京IDEXX元亨生物科技有限公司北京101300 广西大学养禽与禽病研究所

1 禽淋巴白血病病毒的分群除了马立克氏病和网状内皮组织增生症(RE)之外,禽淋巴白血病/劳氏肉瘤代表着禽肿瘤性疾病的第3个群.许多年来马立克氏病已经成为养禽业的主要威胁.自从1988年于英国分离到一个新的亚群ALV以来,白血病就成为肉... 详细信息

1 禽淋巴白血病病毒的分群除了马立克氏病和网状内皮组织增生症(RE)之外,禽淋巴白血病/劳氏肉瘤代表着禽肿瘤性疾病的第3个群.许多年来马立克氏病已经成为养禽业的主要威胁.自从1988年于英国分离到一个新的亚群ALV以来,白血病就成为肉鸡业的一个主要问题,该亚群病毒叫做j亚群.

关键词：淋巴白血病病毒感染养禽业网状内皮组织增生症马立克氏病诊断白血病病毒肿瘤性疾病

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儿科PET/CT的操作和剂量学

中华核医学与分子影像杂志 2019年第5期39卷 314-320页

作者：王宽垠(译) 刘振(译) 兰晓莉(审校) Frederic H. Fahey Alison Goodkind Robert D. MacDougall Leah Oberg Sonja I.Ziniel Richard Cappock Michael j. Callahan Neha Kwatra S. Ted Treves Stephan D. voss 华中科技大学同济医学院附属协和医院核医学科武汉430022 Division of Nuclear Medicine and Molecular Imaging Department of Radiology Boston Children′s Hospital Boston Massachusetts Department of Radiology Harvard Medical School Boston Massachusetts Section of Pediatric Hospital Medicine Department of Pediatrics University of Colorado School of Medicine and Children′s Hospital Colorado Aurora Colorado Department of Radiology Brigham and Women′s Hospital Boston Massachusetts

在儿科PET/CT诊疗领域,迄今还没有统一的CT扫描方法的指南。考虑到儿童更易受电离辐射的影响,在最短时间内和最小暴露剂量条件下提供具有诊断质量的图像十分必要。该文描述了CT辐射剂量测定以及儿童PET/CT采集的基本要点。根据对北美19... 详细信息

在儿科PET/CT诊疗领域,迄今还没有统一的CT扫描方法的指南。考虑到儿童更易受电离辐射的影响,在最短时间内和最小暴露剂量条件下提供具有诊断质量的图像十分必要。该文描述了CT辐射剂量测定以及儿童PET/CT采集的基本要点。根据对北美19所儿科PET/CT机构的调查,描述了儿科PET/CT技术的多样性。调查结果表明,尽管大多数机构采用自动管电流调制,但在实际应用中各机构间仍存在2~3倍的差异,这说明需要统一的指南。该文介绍了作者所在机构研发的多序列PET/CT采集技术,此技术可以兼顾在重要部位视野内获得有诊断质量的CT图像,以及在其余部位应用低辐射技术进行显像。这种方法使患者所受辐射剂量减少,同时将PET和具有诊断质量的CT集成在单次采集中。儿科PET/CT的标准化在保证适中水平的图像质量的同时,为患者提供了减少辐射剂量的机会。

关键词：儿科辐射剂量测定 PET/CT 计算机体层摄影术

主动脉狭窄时心肌细胞因子表达高于特发性扩张型心肌病

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世界核心医学期刊文摘（心脏病学分册） 2005年第12期1卷 49-50页

作者： Vanderheyden M. Paulus W. j. voss M. 任付先 Cardiovascular Centre Onze Lieve Vrouw Ziekenhuis Moorselboon 164 9400 Aalst Belgium

Objective: To investigate cytokine gene expression in patients with aortic valve stenosis(AS) and with idiopathic dilated cardiomyopathy(DCM), and to correlate wall stress with myocardial proinflammatory cytokine gene expression. Methods: Human left ventricular(LV) myocardial biopsies were obtained for subsequent reverse transcription polymerase chain reaction of tumour necrosis factor α(TNFα), interleukin(IL)-1β, and IL-6 mRNA. The study population consisted of 24 patients with AS and 10 patients with idiopathic DCM. Results: Patients with AS had a larger ejection fraction(56(5) v 37(4)%, p< 0.01), smaller LV end diastolic volumes(146(11) v 267(21) ml, p< 0.01), and lower end systolic wall stress(44(7) v 112(11)kdyn/cm2, p< 0.001). Upregulation of TNFα, IL-1β, and IL-6 gene expression was detected in both groups. However, TNFαgene expression was significantly higher in AS than in DCM(p=0.009). No correlation was found between haemodynamic parameters and TNFαgene expression. In patients with AS there was a strong inverse relation between circulating TNFαand TNFαgene expression(r=-0.685, p=0.014), between circulating TNFαand IL-1βgene expression(r=-0.664, p=0.018), and between soluble TNF receptor 2 and TNFαgene expression(r=-0.685, p=0.020). Myocardial gene expression of TNFαwas significantly higher in patients with well compensated AS than in patients with decompensated AS(p=0.017). Similarly, patients with decompensated DCM were characterised by significantly lower TNFαgene expression than were patients with well compensated DCM(p=0.011). Conclusion: TNFαgene expression is significantly higher in patients with pressure overload than in normal hearts, in patients with idiopathic DCM, and in patients with compensated versus decompensated heart failure. Secondly, in patients with AS proinflammatory cytokine gene expression did not affect systolic performance. The higher TNFαgene expression in patients with compensated heart failure suggests that cytokine gene express

关键词：主动脉狭窄细胞因子表达基因表达室壁应力失代偿性炎性细胞因子射血分数主动脉瓣狭窄研究人群舒张末期容积