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Using a temporal phylogenetic method to harmonize familyand genus-level classification in the largest clade of lichen-forming fungi

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Fungal Diversity 2017年第3期84卷 101-117页

作者： Pradeep K.Divakar Ana Crespo Ekaphan Kraichak Steven D.Leavitt Garima Singh imke schmitt H.Thorsten Lumbsch Departamento de Biología Vegetal II Facultad de FarmaciaUniversidad Complutense de Madrid28040 MadridSpain Department of Botany Faculty of ScienceKasetsart UniversityBangkokThailand Department of Biology and M.L.Bean Life Science Museum Brigham Young University4102 Life Science BuildingProvoUT 84602USA Department of Biological Sciences Institute of EcologyEvolution and DiversityGoethe Universitat and Senckenberg Biodiversity and Climate Research Centre(BiK-F)Frankfurt am MainGermany Science&Education The Field MuseumChicagoILUSA

Although classification at supra-specific ranks is inherently arbitrary,comparable taxonomic ranks within clades can facilitate more consistent classifications and objective comparisons among taxa.Different circumscriptions of the hyper-diverse lichen-forming fungal family Parmeliaceae and widely different generic circumscriptions among authors have been proposed.For this study,we use a recently developed temporal approach that uses timecalibrated chronograms to identify temporal bands for specific ranks in Parmeliaceae and allied groups with the overarching goal of establishing a consistent,stable classification.A data set of 330 species,representing 73 genera in the family and 52 species of related families was used to address the circumscription of Parmeliaceae and its genera following the proposed temporal approach.Based on the results of this study,we propose a revised,temporal-based classification for Parmeliaceae,including all clades that share a common ancestor 102.13–112.88 Ma for families and a time window of 29.45–32.55 Ma for genera.Fortyfive of the currently accepted genera in Parmeliaceae were supported in their current circumscription.Two subfamilies are accepted within Parmeliaceae:Protoparmelioideae Divakar et al.***.nov.,including Protoparmelia and the resurrected genus Maronina,and Parmelioideae,including the bulk of genera in the family.The new genus Austromelanelixia Divakar et al.is proposed to accommodate a clade of southern Hemisphere species previously included in Melanelixia.Eumitria and tentatively Dolichousnea are resurrected as genera separate from Usnea.The following genera are reduced to synonymy:Allocetraria,Cetrariella,Usnocetraria,and Vulpicida with Cetraria;Arctocetraria,Cetreliopsis,Flavocetraria,Kaernefeltia,Masonhalea,Tuckermanella,and Tuckermannopsis with Nephromopsis;and the lichenicolous genera Nesolechia and Raesaenenia with the lichen-forming genera Punctelia and Protousnea,respectively.A total of 47 new combinations and three new names at the species level are propos

关键词： Ascomycota Gypsoplacaceae Lecanorales Lichenized fungi Parmeliaceae Phylogeny Protoparmelia Taxonomy Taxonomicranks

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Numerical Optimization by Finite Element Method of Stainless Steel/Glass-Epoxy Composite Bolted Joint under Tension and Compression

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Engineering（科研） 2024年第4期16卷 102-122页

作者： Christian schmitt Arnaud Kremeur Pawel Lipinski Julien Capelle National Engineering School of Metz University of Lorraine Metz France

The aim of this study was to optimize the geometry and the design of metallic/composite single bolted joints subjected to tension-compression loading. For this purpose, it was necessary to evaluate the stress state in each component of the bolted join. The multi-material assembly was based on the principle of double lap bolted joint. It was composed of a symmetrical balanced woven glass-epoxy composite material plate fastened to two stainless sheets using a stainless pre-stressed bolt. In order to optimize the design and the geometry of the assembly, ten configurations were proposed and studied: a classical simple bolted joint, two joints with an insert (a BigHeadR insert and a stair one) embedded in the composite, two “waved” solutions, three symmetrical configurations composed of a succession of metallic and composites layers, without a sleeve, with one and with two sleeves, and two non-symmetrical constituted of metallic and composites layers associated with a stair-insert (one with a sleeve and one without). A tridimensional Finite Element Method (FEM) was used to model each configuration mentioned above. The FE models taked into account the different materials, the effects of contact between the different sheets of the assembly and the pre-stress in the bolt. The stress state was analyzed in the composite part. The concept of stress concentration factor was used in order to evaluate the stress increase in the highly stressed regions and to compare the ten configurations studied. For this purpose, three stress concentration factors were defined: one for a monotonic loading in tension, another for a monotonic loading in compression, and the third for a tension-compression cyclic loading. The results of the FEM computations showed that the use of alternative metallic and composite layers associated with two sleeves gived low values of stress concentration factors, smaller than 1.4. In this case, there was no contact between the bolt and the composite part and the most stressed region was not the vici

关键词： Bolted Joint Glass-Epoxy Composite Clearance Hybrid Steel-Composite

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Phylogenomic analysis of 2556 single-copy protein-coding genes resolves most evolutionary relationships for the major clades in the most diverse group of lichen-forming fungi

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Fungal Diversity 2018年第5期92卷 31-41页

作者： David Pizarro Pradeep K.Divakar Felix Grewe Steven D.Leavitt Jen-Pan Huang Francesco Dal Grande imke schmitt Mats Wedin Ana Crespo H.Thorsten Lumbsch Departamento de Farmacologı́a Farmacognosia y BotánicaFacultad de FarmaciaUniversidad Complutense de Madrid28040 MadridSpain Science&Education The Field Museum1400 S.Lake Shore DriveChicagoILUSA Department of Biology and M.L.Bean Life Science Museum Brigham Young UniversityLife Science Building 4102ProvoUT 84602USA Senckenberg Biodiversity and Climate Research Centre(SBiK-F) Senckenberganlage 2560325 Frankfurt am MainGermany Institute of Ecology Evolution and DiversityGoethe UniversityFrankfurt am MainMax-von-Laue-Str.960438 Frankfurt am MainGermany Department of Botany Swedish Museum of Natural HistoryPO Box 5000710405 StockholmSweden

Phylogenomic datasets continue to enhance our understanding of evolutionary relationships in many lineages of organisms.However,genome-scale data have not been widely implemented in reconstructing relationships in lichenized fungi.Here we generate a data set comprised of 2556 single-copy protein-coding genes to reconstruct previously unresolved rela-tionships in the most diverse family of lichen-forming fungi,Parmeliaceae.Our sampling included 51 taxa,mainly from the subfamily Parmelioideae,and represented six of the seven previously identified major clades within the family.Our results provided strong support for the monophyly of each of these major clades and most backbone relationships in the topology were recovered with high nodal support based on concatenated dataset and species tree analyses.The alectorioid clade was strongly supported as sister-group to all remaining clades,which were divided into two major sister-groups.In the first major clade the anzioid and usneoid clades formed a strongly supported sister-group relationship with the cetrarioid?hypogymnioid group.The sister-group relationship of Evernia with the cetrarioid clade was also strongly supported,whereas that between the anzioid and usneoid clades needs further investigation.In the second major clade Oropogon and Platismatia were sister to the parmelioid group,while the position of Omphalora was not fully resolved.This study demonstrates the power of genome-scale data sets to resolve long-standing,ambiguous phylogenetic rela-tionships of lichen-forming fungi.Furthermore,the topology inferred in this study will provide a valuable framework for better understanding diversification in the most diverse lineage of lichen-forming fungi,Parmeliaceae.

关键词： Fungi Lecanorales Lichenized fungi Parmeliaceae Parmelioideae Phylogeny Systematics

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In memoriamWalter Joseph Bock—a life dedicated to teaching and research in the biological sciences(20 November 1933-27 January 2022)

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Integrative Zoology 2022年第6期17卷 1215-1218页

作者： Michael schmitt John BUCKERIDGE Universität Greifswald Allgemeine&Systematische ZoologieGreifswaldGermany Professor Emeritus RMIT UniversityMelbourneVictoriaAustralia

Walter Joseph Bock(Fig.1)was born in Woodhaven,Queens County,New York,NY(USA),the second of 4 children of Paul and Anne Bock,née Kalsch.He grew up in a German speaking family who discontinued speaking German only at the outset of WWII.From 1947 to 1951 he attended Brooklyn Technical High School,where there was considerable emphasis on technological subjects.In 1951,he entered Cornell University in Ithaca,NY,graduating with a Bachelor of Science in 1955.At Cornell,he attended a short lecture series presented by the famed ethologist Konrad Lorenz,and began an association with the ornithologist Charles Sibley.These links provided Walter with a growing appreciation of the wonders of the world of biology.

关键词： teaching Walter continued

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Mitophagy:From the dark into the spotlight

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Molecular Plant 2023年第10期16卷 1487-1489页

作者： Vivian schmitt Olivier Van Aken Department of Biology Lund UniversityLundSweden

Despite the generally placid appearance of plants,many dynamicprocesses take place inside a plant cell.One such process thathas garnered attention in recent years is termed"autophagy."While originally discovered in yeast,our understanding of autophagy in plants has improved significantly.Autophagy is considered a cellular recycling system in which cellular components oreven entire organelles can be encapsulated by a membranestructure(autophagosome)and then transported to the vacuole(in plants)for degradation and re-use.

关键词： attention organelle spite

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Molecular dynamics simulation of the Stribeck curve: Boundary lubrication, mixed lubrication, and hydrodynamic lubrication on the atomistic level

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摩擦:英文版 2023年第12期11卷 2342-2366页

作者： Simon STEPHAN Sebastian schmitt Hans HASSE Herbert M.URBASSEK Laboratory of Engineering Thermodynamics(LTD) Department of Mechanical and Process EngieeringTU KaiserslauternRheinland-Pfalz 67663Germany Physics Department and Research Center(OPTIMAS) TU KaiserslauternRheinland-Pfalz 67663Germany

Lubricated contact processes are studied using classical molecular dynamics simulations for determining the entire range of the Stribeck curve.Therefore,the lateral movement of two solid bodies at different gap height are studied.In each simulation,a rigid asperity is moved at constant height above a flat iron surface in a lubricating fluid.Both methane and decane are considered as lubricants.The three main lubrication regimes of the Stribeck curve and their transition regions are covered by the study:Boundary lubrication(significant elastic and plastic deformation of the substrate),mixed lubrication(adsorbed fluid layer dominates the process),and hydrodynamic lubrication(shear flow is set up between the surface and the asperity).We find the formation of a tribofilm in which lubricant molecules are immersed into the metal surface—not only in the case of scratching,but also for boundary lubrication and mixed lubrication.The formation of a tribofilm is found to have important consequences for the contact process.Moreover,the two fluids are found to show distinctly different behavior in the three lubrication regimes:For hydrodynamic lubrication(large gap height),decane yields a better tribological performance;for boundary lubrication(small gap height),decane shows a larger friction coefficient than methane,which is due to the different mechanisms observed for the formation of the tribofilm;the mixed lubrication regime can be considered as a transition regime between the two other regimes.Moreover,it is found that the nature of the tribofilm depends on the lubricant:While methane particles substitute substrate atoms sustaining mostly the crystalline structure,the decane molecules distort the substrate surface and an amorphous tribofilm is formed.

关键词： boundary lubrication mixed lubrication hydrodynamic lubrication molecular dynamics simulation tribofilm

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Multiscale morphological analysis of bone microarchitecture around Mg-10Gd implants

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Bioactive Materials 2023年第12期30卷 154-168页

作者： Sandra Sefa Jonathan Espiritu Hanna Cwieka imke Greving Silja Flenner Olga Will Susanne Beuer D.C Florian Wieland Regine Willumeit-Romer Berit Zeller-Plumhoff Institute of Metallic Biomaterials Helmholtz Zentrum HereonGeesthachtGermany Syntellix AG HannoverGermany Institute of Materials Physics Helmholtz Zentrum HereonGeesthachtGermany Molecular Imaging North Competence Center Kiel UniversityKielGermany Fraunhofer Institut für Integrierte Systeme und Bauelementetechnologie(IISB) ErlangenGermany

The utilization of biodegradable magnesium(Mg)-based implants for restoration of bone function following trauma represents a transformative approach in orthopaedic application.One such alloy,magnesium-10 weight percent gadolinium(Mg-10Gd),has been specifically developed to address the rapid degradation of Mg while enhancing its mechanical properties to promote bone healing.Previous studies have demonstrated that Mg-10Gd exhibits favorable osseointegration;however,it exhibits distinct ultrastructural adaptation in comparison to conventional implants like titanium(Ti).A crucial aspect that remains unexplored is the impact of Mg-10Gd degradation on the bone microarchitecture.To address this,we employed hierarchical three-dimensional imaging using synchrotron radiation in conjunction with image-based finite element modelling.By using the methods outlined,the vascular porosity,lacunar porosity and the lacunar-canaliculi network(LCN)morphology of bone around Mg-10Gd in comparison to Ti in a rat model from 4 weeks to 20 weeks post-implantation was investigated.Our investigation revealed that within our observation period,the degradation of Mg-10Gd implants was associated with significantly lower(p<0.05)lacunar density in the surrounding bone,compared to Ti.Remarkably,the LCN morphology and the fluid flow analysis did not significantly differ for both implant types.In summary,a more pronounced lower lacunae distribution rather than their morphological changes was detected in the surrounding bone upon the degradation of Mg-10Gd implants.This implies potential disparities in bone remodelling rates when compared to Ti implants.Our findings shed light on the intricate relationship between Mg-10Gd degradation and bone microarchitecture,contributing to a deeper understanding of the implications for successful osseointegration.

关键词： Biodegradable magnesium implants Lacunar-canalicular network(LCN) Vascular porosity Synchrotron radiation micro computed tomography(SRμCT) Transmission x-ray microscopy(TXM)

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Detailing the influence of PEO-coated biodegradable Mg-based implants on the lacuno-canalicular network in sheep bone:A pilot study

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Bioactive Materials 2023年第8期26卷 14-23页

作者： Jonathan Espiritu Sandra Sefa Hanna Cwieka imke Greving Silja Flenner Regine Willumeit-Römer Jan-Marten Seitz Berit Zeller-Plumhoff Syntellix AG HannoverGermany Institute of Metallic Biomaterials Helmholtz-Zentrum HereonGeesthachtGermany Institute of Materials Physics Helmholtz-Zentrum HereonGeesthachtGermany

An increasing prevalence of bone-related injuries and aging geriatric populations continue to drive the orthopaedic implant market.A hierarchical analysis of bone remodelling after material implantation is necessary to better understand the relationship between implant and bone.Osteocytes,which are housed and communicate through the lacuno-canalicular network(LCN),are integral to bone health and remodelling processes.Therefore,it is essential to examine the framework of the LCN in response to implant materials or surface treatments.Biodegradable materials offer an alternative solution to permanent implants,which may require revision or removal surgeries.Magnesium alloys have resurfaced as promising materials due to their bone-like properties and safe degradation in vivo.To further tailor their degradation capabilities,surface treatments such as plasma electrolytic oxidation(PEO)have demonstrated to slow degradation.For the first time,the influence of a biodegradable material on the LCN is investigated by means of non-destructive 3D imaging.In this pilot study,we hypothesize noticeable variations in the LCN caused by altered chemical stimuli introduced by the PEO-coating.Utilising synchrotron-based transmission X-ray microscopy,we have characterised morphological LCN differences around uncoated and PEO-coated WE43 screws implanted into sheep bone.Bone specimens were explanted after 4,8,and 12 weeks and regions near the implant surface were prepared for imaging.Findings from this investigation indicate that the slower degradation of PEO-coated WE43 induces healthier lacunar shapes within the LCN.However,the stimuli perceived by the uncoated material with higher degradation rates induces a greater connected LCN better prepared for bone disturbance.

关键词： Nanotomography Lacuno-canalicular network Bone Magnesium Biodegradable implants

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A force-compensated compliant MEMS-amplifier with electrostatic anti-springs

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微系统与纳米工程(英文) 2023年第3期9卷 235-244页

作者： Philip schmitt Martin Hoffmann Microsystems Technology Ruhr-Universität BochumUniversitätsstr.15044801 BochumGermany

In this paper,an electrostatic compliant mechanical amplifier intended for force-compensated displacement amplification in MEMS sensor applications is described.Usually,mechanical transformers that enhance a small input displacement into a large output displacement generate large forces at the input of the transformer.The microsystem proposed here allows for the reduction and compensation of the input stiffness of the amplifier and any mechanical components connected to it while providing a constant amplification ratio at the same time.The amplifying mechanism features bidirectional electrostatic anti-springs enabling the control of the stiffness by applying a constant DC voltage.The electrode design of the anti-springs and its influence on the force-displacement characteristic,the side instability and the maximal displacement are studied through analytical approaches and supported by FEA and by experiments.Based on the derived models,a compliant electromechanical amplifier is developed,featuring an amplification ratio of 50.For this amplifier the initial input stiffness of 422 N/m could be reduced to 6.8 N/m by applying a voltage of 100 V.As an additional application,we show how the amplifier can be used as a mechanical force sensor with tuneable sensitivity,where the forces at the input are transformed into large output displacements.Through experiments,we show how the sensitivity can be adjusted and increased by a factor of 25 by applying a voltage at the anti-springs.

关键词： amplifier electrostatic spring

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老普林尼;两千年前的远见

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环球科学 2024年第5期 56-61页

作者：斯特凡纳·施米特戚译引(译) 法国国家科学研究中心(CNRS)亨利-庞加莱档案馆不详

这篇来自《科学美国人》法国版的文章再次解读了《博物志》:这是一部关于古典时代的人们如何认识和利用自然的独特档案,也是一份对自然资源耗竭的预警。公元23年,老普林尼(Pline I'Ancien)出生,公元79年,他在维苏威火山喷发中死去。但... 详细信息

这篇来自《科学美国人》法国版的文章再次解读了《博物志》:这是一部关于古典时代的人们如何认识和利用自然的独特档案,也是一份对自然资源耗竭的预警。公元23年,老普林尼(Pline I'Ancien)出生,公元79年,他在维苏威火山喷发中死去。但老普林尼不仅留下了他死亡时的壮烈故事,还留下了巨著《博物志》(Naturalis historia),其中汇集了当时关于自然事物及其用途的所有知识。

关键词：《博物志》古典时代维苏威火山普林尼《科学美国人》档案

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