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Evidence for the Role Evolutionary Increase Yield in Cotton of Transfer Cells in the in Seed and Fiber Biomass

Molecular Plant 2010年第6期3卷 1075-1086页

作者： deborah A. Pugh Christina E. Offler Mark J. talbot Yong-Ling Ruan School of Environmental and Life Sciences University of Newcastle Callaghan NSW 2308 Australia Australia-China Research Centre for Crop Improvement University of Newcastle Callaghan NSW 2308 Australia CSIRO Plant Industry Canberra ACT 2601 Australia

Transfer cells （TCs） are specialized cells exhibiting invaginated wall ingrowths （Wls）, thereby amplifying their plasma membrane surface area （PMSA） and hence the capacity to transport nutrients. However, it remains unknown as to whether TCs play a role in biomass yield increase during evolution or domestication. Here, we examine this issue from a comparative evolutionary perspective. The cultivated tetraploid Ad genome species of cotton and its A and d genome diploid progenitors displayed high, medium, and low seed and fiber biomass yield, respectively. In all three species, cells of the innermost layer of the seed coat juxtaposed to the filial tissues trans-differentiated to a TC morphology. Electron microscopic analyses revealed that these TCs are characterized by sequential formation of flange and reticulate Wls during the phase of rapid increase in seed biomass. Significantly, TCs from the tetraploid species developed substantially more flange and reticulate Wls and exhibited a higher degree of reticulate WI formation than their progenitors. Consequently, the estimated PMSA of TCs of the tetraploid species was about 4 and 70 times higher than that of TCs of the A and d genome progenitors, respectively, which correlates positively with seed and fiber biomass yield. Further, TCs with extensive Wls in the tetraploid species had much stronger expression of sucrose synthase, a key enzyme involved in TC Wl formation and function, than those from the A and d progenitors. The analyses provide a set of novel evidence that the development of TC Wls may play an important role in the increase of seed and fiber biomass yield through polyploidization during evolution.

关键词： Callose cell wall cellulose cotton fiber evolution polyploidization seed development sucrose synthase transfer cell.

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长时间工作与隐蔽性及持续性高血压患病率的关系

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中华高血压杂志 2019年第12期27卷 1219-1219页

作者： Trudel X Brisson C Gilbert-Ouimet M Vézina M talbot d Milot A 赵狄(摘译) 刘莉(审校) 不详

Hypertension,2019,75(2):532-5关于长时间工作对血压影响的研究结果并不一致,不同的结果可能是由于血压测量的局限以及缺乏对隐蔽性高血压的认识。该研究旨在探讨长时间工作的个体隐蔽性及持续性高血压的患病率是否更高。研究人员收集3... 详细信息

Hypertension,2019,75(2):532-5关于长时间工作对血压影响的研究结果并不一致,不同的结果可能是由于血压测量的局限以及缺乏对隐蔽性高血压的认识。该研究旨在探讨长时间工作的个体隐蔽性及持续性高血压的患病率是否更高。研究人员收集3 547例白领5年3个时间点的数据。长时间工作是根据自我报告,血压采用Spacelabs 90207测量。工作场所血压是指工作场所休息时所测前3次血压的均值。动态血压是指白天工作时间每15 min测量血压的均值。

关键词：持续性高血压患病率隐蔽性高血压

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Metal Hexaborides with Sc, Ti or Mn

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Modeling and Numerical Simulation of Material Science 2013年第4期3卷 158-169页

作者： Ian d. R. Mackinnon Jose A. Alarco Peter C. talbot Institute for Future Environments Brisbane Australia Science and Engineering Faculty School of Chemistry Physics and Mechanical Engineering Queensland University of Technology Brisbane Australia

Comparison of well-determined single crystal data for stoichiometric, or near-stoichiometric, metal hexaborides confirms previously identified lattice parameter trends using powder diffraction. Trends for both divalent and trivalent forms suggest that potential new forms for synthesis include Sc and Mn hexaborides. density Functional Theory (dFT) calculations for KB6, CaB6, YB6, LaB6, boron octahedral clusters and Sc and Mn forms show that the shapes of bonding orbitals are defined by the boron framework. Inclusion of metal into the boron framework induces a reduction in energy ranging from 1 eV to 6 eV increasing with ionic charge. For metals with d1 character, such a shift in energy brings a doubly degenerate band section along with the G-M reciprocal space direction within the conduction bands tangential to the Fermi surface. ScB6 band structure and density of states calculations show directions and gap characteristics similar to those of YB6 and LaB6. These calculations for ScB6 suggest that it may be possible to realize superconductivity in this compound if synthesized.

关键词： Metal Hexaborides Electronic Structure Superconductivity Boron Framework

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Comparison of Functionals for Metal Hexaboride Band Structure Calculations

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Modeling and Numerical Simulation of Material Science 2014年第2期4卷 53-69页

作者： Jose A. Alarco Peter C. talbot Ian d. R. Mackinnon Institute for Future Environments Queensland University of Technology Gardens Point Campus BrisbaneAustralia Institute for Future Environments Queensland University of Technology Gardens Point Campus BrisbaneAustralia Science and Engineering Faculty Queensland University of Technology Gardens Point Campus BrisbaneAustralia

density functional calculations of the electronic band structure for superconducting and semiconducting metal hexaborides are compared using a consistent suite of assumptions and with emphasis on the physical implications of computed models. Spin polarization enhances mathematical accuracy of the functional approximations and adds significant physical meaning to model interpretation. For YB6 and LaB6, differences in alpha and beta projections occur near the Fermi energy. These differences are pronounced for superconducting hexaborides but do not occur for other metal hexaborides.

关键词： Hexaborides density Functional Theory Band Structure Spin Polarization Superconductivity

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Electron density Response to Phonon dynamics in MgB<sub>2</sub>: An Indicator of Superconducting Properties

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Modeling and Numerical Simulation of Material Science 2018年第2期8卷 21-46页

作者： Jose A. Alarco Peter C. talbot Ian d. R. Mackinnon Institute for Future Environments and Science and Engineering Faculty Queensland University of Technology (QUT) Brisbane Australia

Electron density differences resulting from atom displacement patterns aligned with phonon modes in MgB2 have been calculated using density functional theory (dFT). The extent of phonon anomalies, identified as indicators of the superconducting transition temperature, Tc, under a range of conditions in AlB2-type structures, reduce as boron atoms are displaced from their equilibrium positions along E2g mode directions. The Fermi energy for displacements along the directions of the E2g phonon mode accounts for changes in the covalent B-B bond electronic charge density. We applied differential atom displacements to show that the shifted σ band structure associated with the light effective mass became tangential to the Fermi level and that the Fermi surface undergoes a topological transition at a critical relative displacement of ~0.6% of the boron atoms from equilibrium. The difference in Fermi energies at this critical displacement and at the equilibrium position correspond to the superconducting energy gap. The net volume between tubular σ surfaces in reciprocal space correlated with the depth of the phonon anomaly and, by inference, it is a key to an understanding of superconductivity. This ab initioapproach offers a phenomenological understanding of the factors that determine Tc based on knowledge of the crystal structure.

关键词： Electron density MgB2 Phonon dispersion Kohn Anomaly Phonon dynamics Superconducting Transition Temperature Superconductivity Mechanism

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高血压神经心脏行为训练:一个随机对照试验

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中华高血压杂志 2010年第9期18卷 888-888页

作者：张玲玉叶鹏 Nolan RP Floras JS Harvey PJ Kamath MV Picton PE Chessex C Hiscock N Powell J Catt M Hendrickx H talbot d Chen MH

目前尚不明确行为上的干预是否对高血压患者的药物治疗有益。研究者假设在日常活动中,进行标准化的认知活动(一种精神压力试验)后,利用心率变化带来的生物反馈而设计的神经心脏行为训练(behavioral neurocardiac training, BNT)可通过... 详细信息

目前尚不明确行为上的干预是否对高血压患者的药物治疗有益。研究者假设在日常活动中,进行标准化的认知活动(一种精神压力试验)后,利用心率变化带来的生物反馈而设计的神经心脏行为训练(behavioral neurocardiac training, BNT)可通过改变迷走神经对心率的调控而进一步降低血压。该试验随机入选单纯的高血压患者65例,随机分配到BNT组或者对照组(自行放松),在2月期间进行共6次的家庭训练,[第一段]

关键词：随机对照试验高血压患者行为训练迷走神经心脏心率变化药物治疗日常活动

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In-Situ Carbon Control in the Preparation of Precursors to Boron Carbide by a Non-Aqueous Solution Technique

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材料科学与工程（中英文A版） 2015年第1期5卷 8-20页

作者： Joshua L. Watts Peter C.talbot Jose A. Alarco Ian d. R. Mackinnon Institute for Future Environments Queensland University of Technology Brisbane 4001 Australia Science and Engineering Faculty School of Chemistry Queensland University of Technology Brisbane 4001 Australia

Synthesis of high quality boron carbide (B4C) powders is achieved by carbothermal reduction of boron oxide (B2O3) from a condensed boric acid (H3BO3)/polyvinyl acetate (PVAc) product. Precursor solutions are prepared via free radical polymerisation of vinyl acetate (VA) monomer in methanol in the presence of dissolved H3BO3. A condensed product is then formed by flash evaporation under vacuum. As excess VA monomer is removed at the evaporation step, the polymerisation time is used to manage availability of carbon for reaction. This control of carbon facilitates dispersion of H3BO3 in solution due to the presence of residual VA monomer. B4C powders with very low residual carbon are formed at temperatures as low as 1,250 °C with a 4 hour residence time.

关键词：碳化硼粉末非水溶液制备前体控制聚醋酸乙烯酯技术原位

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制动工况下圆盘/摩擦衬块接触面间动态压力中心的测量(二)

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传动技术 2012年第3期26卷 34-42页

作者： John d.Fieldhouse Naveed Ashraf Chris talbot the Automotive Engineering Research Group University of Huddersfield

本文阐明了活塞尾端或内侧,摩擦衬块在制动产生听觉可分辨的噪声方面的影响。采用独特的技术测量常态制动工况下摩擦衬块/圆盘接触面间的动态中心压力(Cop)。该新技术采用一个在摩擦衬块内嵌入压力感敏膜。本文还提出了摩擦衬块/卡钳接... 详细信息

本文阐明了活塞尾端或内侧,摩擦衬块在制动产生听觉可分辨的噪声方面的影响。采用独特的技术测量常态制动工况下摩擦衬块/圆盘接触面间的动态中心压力(Cop)。该新技术采用一个在摩擦衬块内嵌入压力感敏膜。本文还提出了摩擦衬块/卡钳接触区的共面分析,以及它对圆盘/摩擦衬块Cop位置的影响。该分析表明,活塞尾端情况,影响Cop位置,并进一步说明该中心的移动类似于摩擦衬块支架振动与支架反向。本文包含用12个活塞对立卡钳的附加研究,初始Cop位置可以沿摩擦衬块和径向两个方向变化。结果表明,Cop的运动很明确使制动压力增大。

关键词：制动噪声圆盘制动制动摩擦衬块中心压力压力中心

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