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Morphometric analysis of the Taxus wallichiana complex based on herbarium material

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Morphometric analysis of the Taxus wallichiana complex based...

全国系统与进化植物学研讨会暨第九届系统与进化植物学青年研讨会

作者： michael moeller Robert R．Mill Royal Botanic Garden Edinburgh 20A Inverleith Row Edinburgh EH3 5LRScotlandUK

We used morphological and geographical data of 128 herbarium specimens of the Taxus wallichiana-complex in Central Asia to investigate their utilisation in discriminating and identifying taxa included in the complex. The 26 leaf and one bud scale character were used to separate T. fuana, T. wallichiana var. wallichiana, T. wallichiana var. mairei, T. wallichiana var. chinensis and T. sumatrana by K-means clustering and dendrograms using Ward’s distance. Out of the 27 characters examined 21 were found to be well correlated with geographic patterns. T. fuana was the most distant taxon, while the T. sumatrana clustered among the T. wallichiana varieties. After correcting mis-identifications of the specimens in T. wallichiana. the varieties occupied discrete geographic ranges, except for some limited sympatry of varieties mairei and chinensis east of the Tanaka-Kaiyong lines and the Pendi Basin in Sichuan province, China. Our analysis demonstrate the importance of consistency in character selection and definition in the identification of morphologically difficult taxa and the power of combining morphometric and geographic data in clarifying their spatial distribution.

关键词： China geographic distribution morpho metrics PCA Taxus wallichiana complex

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红豆杉属的分子系统学研究

红豆杉属的分子系统学研究

Fabrication of sub-20 nm MoS_(2) horizontal nanowire on silicon substrates by inclusion of precursors into polystyrene-bpolyethylene oxide nanopatterns: Detailed structural investigation

全国系统与进化植物学研讨会暨第九届系统与进化植物学青年研讨会

作者：高连明李德铢 michael moeller 中国科学院昆明植物研究所生物多样性与生物地理学重点实验室 Royal Botanic Garden Edinburgh 20A Inverleith Row Edinburgh EH3 5LRScotlandUK

红豆杉属是红豆杉科中最大的属,约有9种2变种,广布于北半球,是第三纪孑遗植物。红豆杉属的起源虽然可追述到侏罗纪,但种间的形态差异较小,无论是红豆杉属的分类还是种间的演化关系至今都不十分清楚。本文以白豆杉属为外类群,对红豆杉属... 详细信息

红豆杉属是红豆杉科中最大的属,约有9种2变种,广布于北半球,是第三纪孑遗植物。红豆杉属的起源虽然可追述到侏罗纪,但种间的形态差异较小,无论是红豆杉属的分类还是种间的演化关系至今都不十分清楚。本文以白豆杉属为外类群,对红豆杉属所有现存的9种2变种的43个样品的核糖体基因ITS片段和叶绿体基因trnL-F区序列进行了系统发育分析,构建系统树来探讨种间系统发育关系,并为红豆杉属植物的分类和物种划分提供分子证据。分子系统学的分析结果表明,红豆杉属为一单系类群,与白豆杉属分化较早。无论基于ITS序列和trnL-F区序列的单独分析还是联合数据分析,产北美东南部的佛罗里达红豆杉(Taxus floridana)与特产墨西哥与危地马拉的Taxus globasa形成稳定的姐妹群关系,得到强烈支持;产欧洲和非洲北部的欧洲红豆杉(Taxus baccata),产西喜马拉雅地区的密叶红豆杉(Taxux fuana),．产东喜马拉雅的须弥红豆杉(Taxus wallichiana ***),产我国台湾和菲律宾的南洋红豆杉(Taxus sumatrana)及分布于华中大巴山脉的红豆杉(Taxus wallichiana ***)和产云南东南部和越南北部的红豆杉各自形成稳定的分支并得到较高的支持率。北美的短叶红豆杉(Taxcus brevifolia)、Taxus floridana 和Taxus globasa亲缘关系较近,构成一个分支并得到强烈的支持,但并没有与同产北美的Taxus canadensis形成相同的分支,种间关系不明确。欧洲红豆杉与东北红豆杉的关系密切,在ITS和联合数据分析中形成姐妹群关系。密叶红豆杉的种级地位得到支持,但与其它种间的关系没有得到解决。须弥红豆杉形成一稳定的分支,作为一个好种得到支持, 而不支持将红豆杉和南方红豆杉作为须弥红豆杉的变种处理。产东亚的红豆杉、南方红豆杉和南洋红豆杉构成一个大的分支(ITS和联合数据分析),形成一种群复合体,在分支内存在6条明显的种系线,可能是这一种群复合体在不同的分布地通过辐射演化形成的。

关键词：红豆杉属系统发育单系类群 ITS trnL-F

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Nano Research 2024年第3期17卷 2145-2153页

作者： Tandra Ghoshal michael A.Morris School of Chemistry AMBER and CRANNTrinity College DublinDublinIrelandD02 AK60

Herein,we demonstrate the fabrication of sub-20 nm MoS_(2) horizontal nanowire arrays on silicon substrates using a self-assembled block copolymer assisted in situ inclusion *** separated long-range ordered polystyrene-b-polyethylene oxide(PS-b-PEO)block copolymer(BCP)line-space nanopatterns were achieved through thermo-solvent *** patterns produced had long-range order and domain sizes>1μ*** BCP structures were lightly etched and modified by anhydrous ethanol to facilitate insertion of molybdenum precursor within the film maintaining the parent BCP *** ordered molybdenum oxide nanowire arrays were then fabricated by ultraviolet(UV)/ozone treatment at room *** oxides were converted to sulphides by thermal evaporation at different temperatures in Ar/H_(2) environment.X-ray photoelectron spectroscopy revealed the composition and phases of the molybdenum oxide and sulphide *** mapping was performed to investigate the interfaces between the oxide and sulphide nanowires with the substrate *** formation and stability of the sulphide nanowires were studied at different *** photoluminescence and Raman properties were studied at different formation temperatures to investigate defects and estimate the number of layers.

关键词： MoS_(2) block copolymer nanowires inclusion X-ray photoelectron spectroscopy(XPS) mapping photoluminescence

Neuronal trafficking as a key to functional recovery in immune-mediated neuropathies

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Neural Regeneration Research 2024年第11期19卷 2331-2332页

作者： Felix Kohle michael Schroeter Department of Neurology University of Cologne and University Hospital CologneCologneGermany

Immune-mediated neuropathies are rare diseases of the peripheral nervous system(PNS),substantially affecting patients’functionality and quality of *** are amenable to immunomodulatory treatments,which in many cases stabilize disease progression,but long-term deficits persist in many *** long-term deficits are particularly observed in monophasic autoimmune neuropathies like Guillain-Barrésyndrome and also in chronic variants,e.g.,chronic inflammatory demyelinating neuropathy(Fadia et al.,2019).

关键词： diseases autoimmune

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Rethinking the egg

National Science Review 2024年第6期11卷 81-82页

作者： michael J.Benton School of Earth Sciences University of Bristol

Our image of early dinosaur eggs must change. Early dinosaur eggs are portrayed as soft-shelled, like those of modern lizards or snakes [1], and yet all the evidence is that early dinosaurs at least laid leathery-shel...

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Design of a Level-3 electric vehicle charging station using a 1-MW solar system via the distributed maximum power point tracking technique

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Clean Energy 2024年第1期8卷 23-35页

作者： Afshin Balal michael Giesselmann Department of Electrical and Computer Engineering Texas Tech UniversityLubbockTX 79409USA

Solar power is mostly influenced by solar irradiation,weather conditions,solar array mismatches and partial shading ***,before installing solar arrays,it is necessary to simulate and determine the possible power *** power point tracking is needed in order to make sure that,at any time,the maximum power will be extracted from the photovoltaic ***,maximum power point tracking is not a suitable solution for mismatches and partial shading *** overcome the drawbacks of maximum power point tracking due to mismatches and shadows,distributed maximum power point tracking is util-ized in this *** solar farm can be distributed in different ways,including one DC-DC converter per group of modules or per *** this paper,distributed maximum power point tracking per module is implemented,which has the highest *** technology is applied to electric vehicles(EVs)that can be charged with a Level 3 charging station in<1 ***,the problem is that charging an EV in<1 hour puts a lot of stress on the power grid,and there is not always enough peak power reserve in the existing power grid to charge EVs at that ***,a Level 3(fast DC)EV charging station using a solar farm by implementing distributed maximum power point tracking is utilized to address this ***,the simulation result is reported using MATLAB®,LTSPICE and the System Advisor *** results show that the proposed 1-MW solar system will provide 5 MWh of power each day,which is enough to fully charge~120 EVs each ***,the use of the proposed photovoltaic system benefits the environment by removing a huge amount of greenhouse gases and hazardous *** example,instead of supplying EVs with power from coal-fired power plants,1989 pounds of CO_(2) will be eliminated from the air per hour.

关键词： electric vehicles(EVs) distributed maximum power point tracking solar farm DC fast-charging station step-up DC-DC converter System Advisor Model economic analysis

Transcranial photobiomodulation for the brain: a wide range of clinical applications

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Neural Regeneration Research 2024年第3期19卷 483-484页

作者： michael R.Hamblin Laser Research Centre Faculty of Health ScienceUniversity of Johannesburg-Doornfontein CampusDoornfonteinSouth Africa

Photobiomodulation therapy(PBMT)is a rapidly growing approach to the healing,stimulation,protection,and regeneration of many human organs and tissue *** started in the 1960s as low-level laser therapy for wound healing,but since then the introduction of light-emitting diodes(LEDs)has dramatically increased the number of applications and reports of positive *** generally uses red(620-700 nm)and/or near-infrared(780-1270 nm)wavelengths of light at an intensity that causes no tissue heating,and its activity is based on well-established biological and cellular mechanisms(de Freitas and Hamblin,2016).While laser therapists continue to use various types of laser in their office practice,LEDs are ideally suited for home use devices because they are completely safe and without any known significant adverse *** the various body parts on which PBMT has been shown to exert beneficial effects,the brain stands out as perhaps the most promising *** has been shown to reduce neuroinflammation,while increasing mitochondrial function,oxygen consumption,and blood flow within the brain(Hamblin,2016).Moreover,PBMT can stimulate the processes of synaptogenesis,neurogenesis,and neuroplasticity thus helping the brain to heal itself.

关键词： healing stimulation wound

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Odd-even effects in the structure and properties of aryl-substituted aliphatic self-assembled monolayers

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Nano Research 2024年第5期17卷 4231-4243页

作者： Piotr Cyganik Andreas Terfort michael Zharnikov Jagiellonian University Faculty of PhysicsAstronomy and Applied Computer ScienceSmoluchowski Institute of PhysicsŁojasiewicza 1130-348 KrakówPoland Institut für Anorganische und Analytische Chemie Universität FrankfurtMax-von-Laue-Straße 760438 FrankfurtGermany Applied Physical Chemistry Heidelberg UniversityIm Neuenheimer Feld 25369120 HeidelbergGermany

Self-assembled monolayers(SAMs)represent an important tool in context of nanofabrication and molecular engineering of surfaces and *** properties of functional SAMs depend not only on the character of the tail groups at the SAM-ambient interface,but are also largely defined by their *** its turn,the latter parameter results from a complex interplay of the structural forces and a variety of other factors,including so called odd-even effects,*** of the SAM structure and properties on the parity of the number(odd or even)of individual building blocks in the backbone of the SAM *** most impressive manifestation of the odd-even effects is the structure of aryl-substituted alkanethiolate SAMs on Au(111)and Ag(111),in which,in spite of the fact that the intermolecular interaction is mostly determined by the aryl part of the monolayers,one observes a pronounced dependence of molecular inclination and,consequently,the packing density of the SAM-forming molecules on the parity of number of methylene units in the alkyl *** we review the properties of the above systems as well as address fundamental reasons behind the odd-even effects,including the existence of a so-called bending potential,which is frequently disregarded in analysis of the structure-building *** generality of the odd-even effects in SAMs is additionally supported by the recent data for SAMs on GaAs,scanning tunneling microscopy data for SAMs on Ag(111),and the data for the monolayers with selenolate and carboxyl anchoring groups on Au(111)and Ag(111).The implications of these effects in terms of the control over the packing density and orientation of the tail groups at the SAM-ambient interface,structural perfection,polymorphism,temperature-driven phase transitions,and SAM stability toward such factors as ionizing radiation,exchange reaction,and electrochemical desorption are *** implications place the odd-even effects as an important tool

关键词： self-assembled monolayers molecular films surface and interface engineering odd-even-effects

Increasing realism in modelling energy losses in railway vehicles and their impact to energy-efficient train control

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Railway Engineering Science 2024年第3期32卷 257-285页

作者： michael Nold Francesco Corman Institute for Transport Planning and Systems ETH ZürichZürichSwitzerland

The reduction of energy consumption is an increasingly important topic of the railway ***-efficient train control(EETC)is one solution,which refers to mathematically computing when to accelerate,which cruising speed to hold,how long one should coast over a suitable space,and when to *** approaches in literature and industry greatly simplify a lot of nonlinear effects,such that they ignore mostly the losses due to energy conversion in traction components and *** fill this research gap,a series of increasingly detailed nonlinear losses is described and *** categorize an increasing detail in this representation as four *** study the impact of those levels of detail on the energy optimal speed *** do this,a standard approach based on dynamic programming is used,given constraints on total travel *** evaluation of multiple test cases highlights the influence of the dynamic losses and the power consumption of auxiliary components on railway trajectories,also compared to multiple *** results show how the losses can make up 50%of the total energy consumption for an exemplary *** them would though result in consistent but limited errors in the optimal ***,more complex trajectories can result in less energy consumption when including the complexity of nonlinear losses than when a simpler model is *** effects are stronger when the trajectory includes many acceleration and braking phases.

关键词： Train trajectory optimization Energy-efficient train control(EETC) Dynamic efficiency Power losses in railway vehicles

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