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Commentary on"Speed and surface steepness affect internal tibial loading during running"

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Journal of Sport and Health Science 2024年第1期13卷 125-126页

作者： michael Baggaley Arash Khassetarash Faculty of Kinesiology University of CalgaryCalgaryAB T2N 1N4Canada McCaig Institute for Bone and Joint Health University of CalgaryCalgaryAB T2N 4Z6Canada

It is a pleasure to write a commentary on the work of *** Rice and colleagues,l who have advanced our understanding of how the mechanical loading environment of the tibia changes as a function of running grade and *** is important that we understand how the tibia is loaded during conditions that an individual is likely to encounter when running as it is these internal loads which we believe are responsible for the development of bone-stress injuries.

关键词： loading injuries likely

Universal Hyperthermal Model for Mass Extinctions

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Journal of Earth Science 2024年第2期35卷 704-707页

作者： michael J.Benton Paleobiology Research Group School of Earth SciencesUniversity of BristolLife Sciences BuildingTyndall AvenueBristolBS81TQUK

INTRODUCTION Earth scientists have long sought universal features of past extinction *** can be argued that each past extinction event was a singularity,caused by combinations of circumstances that are unique in each case,and therefore that the search for common causes is ***,a key feature of the uniformitarian approach to geology is that past processes are the same as modern-day processes and,with that in mind,earth scientists are keen to use their knowledge to contribute some understanding to the study of the present and future climate crisis.

关键词： extinction singularity Extinction

Implementation and validation of a bonded particle model to predict rheological properties of viscoelastic materials

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Particuology 2024年第6期89卷 198-210页

作者： michael Mascara Arno Mayrhofer Stefan Radl Christoph Kloss Institute of Process and Particle Engineering Graz University of TechnologyInffeldgasse 13Graz8010Austria DCS Computing GmbH Industriezeile 35Linz4020Austria

This work focuses on implementing a particle-based method able to characterize viscoelastic materials whose rheological properties,such as storage modulus G′and loss modulus G″,are *** is based on the bonded particle model,with the elastic constitutive relation here substituted with a viscoelastic one to capture time-scale *** Burgers model,vastly used in literature to model viscoelastic systems,is discretized and *** test case used for calibration comprises of a cubic lattice,sheared with a periodic motion,to mimic the effect of a shear *** appropriate filtering of the stress response,the rheological properties are obtained,highlighting the effect of the lattice geometry,as well as the particle size,on the accuracy of the ***,the Burgers parameters are calibrated by analytically fitting the experimental dataset,showing the limitation of the Burgers *** micro-contact parameters are obtained from the macro parameters through appropriate *** completing a frequency sweep,the simulated G′and G″show a relatively large error,around 25%for G’for *** this reason,a more robust model,namely the generalized Maxwell model,has been *** calibration procedure is performed in the same fashion as for the Burgers ***,the tangential micro-contact parameters are scaled *** normal *** scaling parameter,calledα,is calibrated by minimizing the root mean square error between simulation and experimental data,giving errors below 10%in both G′and G″for a large ***,a full ring plate-plate rheometer setup is simulated,and the simulation is compared with the given experimental dataset,again finding a good agreement.

关键词： DEM Rheology Numerical modeling Viscoelasticity

Microscale shaping and rounding of ridge arrays and star pattern features on nickel mould via electrochemical polishing

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Advances in Manufacturing 2024年第2期12卷 207-226页

作者： Sana Zaki Nan Zhang michael D.Gilchrist School of Mechanical and Materials Engineering University College DublinBelfieldDublin 4Ireland

High quality micro mould tools are critical for ensuring defect-free production of micro injection moulded *** demoulding stage of the micro injection moulding can adversely affect the surface integrity due to friction,adhesion and thermal stresses between the metallic mould and polymeric replicated *** the present work,we propose the use of precision electropolishing(EP)as a shaping and polishing process to control the draft angle and fillet radius of micro features in order to ease *** defects that occur in replicated polymer parts include cracks,burrs and distorted features.A nickel mould having multiple linear ridges and star shape patterns was designed for the present investigation to have characteristic dimensions ranging from 10μm to 150μm and with various aspect ratios to study the effect of electropolishing on modifying the shape of micro features and surface morphology.A transient 2D computational analysis has been conducted to anticipate the effect of shaping on the Ni mould after electrochemical polishing with non-uniform material removal rates,based on the distribution of current *** experimental results indicate that after shaping using EP,the draft angle of star-patterns and linear patterns can be effectively increased by approximately 3.6°,while the fillet radius increases by up to 5.0μ*** controlling the electropolishing process,the surface roughness can be maintained under 50 *** work uses a green and environmental friendly nickel sulfamate electrolyte which can be effective for shaping of nickel micro features without causing any surface deposition.

关键词： Micro feature shaping and electropolishing Micro mould tools Green electrolyte Demoulding micro patterns

Stacking transition in rhombohedral graphite

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Frontiers of physics 2019年第1期14卷 67-73页

作者： Tataiana Latychevskaia Seok-Kyun Son Yaping Yang Dale Chancellor michael brown Servet Ozdemir Ivan Madan Gabriele Berruto Fabrizio Carbone Artem Mishchenko Kostya S. Novoselov Institute of Physics Laboratory for Ultrafast Microscopy and Electron Scattering (LUMES)école Polytechnique Fédérale de Lausanne (EPFL) CH-1015 Lausanne Switzerland National Graphene Institute University of Manchester Oxford Road Manchester M13 9PL UK School of Physics and Astronomy University of Manchester Oxford Road Manchester M13 9PL UK

Few-layer graphene (FLG) has recently been intensively investigated for its variable electronic properties, which are defined by a local atomic arrangement. While the most natural arrangement of layers in FLG is ABA (Bernal) stacking, a metastable ABC (rhombohedral) stacking, characterized by a relatively high-energy barrier, can also occur. When both types of stacking occur in one FLG device, the arrangement results in an in-plane heterostructure with a domain wall (DW). In this paper, we present two approaches to demonstrate that the ABC stacking in FLG can be controllably and locally turned into the ABA stacking. In the first approach, we introduced Joule heating, and the transition was characterized by 2D peak Raman spectra at a submicron spatial resolution. The transition was initiated in a small region, and then the DW was controllably shifted until the entire device became ABA stacked. In the second approach, the transition was achieved by illuminating the ABC region with a train of 790-nm-wavelength laser pulses, and the transition was visualized by transmission electron microscopy in both diffraction and dark-field imaging modes. Further, using this approach, the DW was visualized at a nanoscale spatial resolution in the dark-field imaging mode.

关键词： graphene graphite van der Waals heterostructures domain wall Raman spectroscopy transmission electron microscopy electron diffraction structural transition

Regulating depletion region enables highly efficient and stable perovskite solar cells

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Science China Chemistry 2024年第9期67卷 2783-2784页

作者： Chun-Yun Wang michael Saliba Institute for Photovoltaics(ipv) University of Stuttgart70569 StuttgartGermany IEK5-Photovoltaics Forschungszentrum Jülich52425 JülichGermany

Perovskite solar cells(PSCs)have made impressive strides in recent years with the power conversion efficiency(PCE)now exceeding 26%[1],which is comparable to established technologies such as ***,the ion migration in perovskites causes undesirable hysteresis and *** affects the long-term operational stability of PSCs,hampering a possible industrialization.

关键词： perovskite depletion exceeding

苏鲁造山带超高压榴辉岩中多期重晶石的结晶机制与指示意义

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吉林大学学报(地球科学版) 2015年第S1期 267-267页

作者：王淞杰王璐 michael brown 中国地质大学(武汉)地质过程与矿产资源国家重点实验室马里兰大学帕克分校地质系

高压—超高压变质流体作用一直是国际地学界研究的前沿课题,这些变质流体不仅直接参与变质反应,而且对于超高压岩石部分熔融、壳-幔相互作用、改变超高压岩石的相变和流变性质有非常大的促进作用。近年来,超高压榴辉岩中重晶石包裹体和... 详细信息

高压—超高压变质流体作用一直是国际地学界研究的前沿课题,这些变质流体不仅直接参与变质反应,而且对于超高压岩石部分熔融、壳-幔相互作用、改变超高压岩石的相变和流变性质有非常大的促进作用。近年来,超高压榴辉岩中重晶石包裹体和多相包裹体的产出得到广泛关注,因其是俯冲带高盐度流体存在的重要指示标志。然而,由于缺乏指示重晶石结晶时间的证据,超高压变质过程中重晶石的结晶过程及地质意义仍存在一定争议。为解决上述问题,我们以中国东部苏鲁造山带仰口超高压榴辉岩为研究对象,

关键词：造山带榴辉岩相流体作用变质反应包裹体高盐度结晶时间俯冲带结晶过程绿辉石

Single carbon metabolism–A new paradigm for microbial bioprocesses?

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Synthetic and Systems Biotechnology 2024年第2期9卷 322-329页

作者： michael Baumschabl Özge Ata Diethard Mattanovich Austrian Centre of Industrial Biotechnology(ACIB) Vienna1190Austria University of Natural Resources and Life Sciences Department of BiotechnologyInstitute of Microbiology and Microbial BiotechnologyViennaAustria

Increasing atmospheric carbon dioxide levels,a reduction of arable land area and the dependence of first and second generation biotechnology feedstocks on agricultural products,call for alternative,sustainable feedstock sources for industrial *** direct use of CO_(2)or conversion of CO_(2)into other single carbon(C1)sources have great potential as they might help to reduce carbon emissions and do not compete with agricultural land *** we discuss the microbial use of C1 carbon sources,their potential applications in biotechnology,and challenges towards sustainable C1-based industrial biotechnology *** focus on methanol,formic acid,methane,syngas,and CO_(2)as feedstocks for bioprocesses,their assimilation pathways,current and emerging applications,and limitations of their *** mini-review is intended as a first introduction for researchers who are new to the field of C1 biotechnology.

关键词： Sustainability BioeconomyCarbon dioxide Methanol Formate Methane

Diabetes and pulmonary infection:how hyperglycaemia shapes the immune system

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Signal Transduction and Targeted Therapy 2024年第4期9卷 1245-1246页

作者： Christian Herder michael Roden Nicolas Venteclef Institute for Clinical Diabetology German Diabetes CenterLeibniz Center for Diabetes Research at Heinrich Heine University Düsseldorf40225DüsseldorfGermany German Center for Diabetes Research(DZD) Partner Düsseldorf85764München-NeuherbergGermany Department of Endocrinology and Diabetology Medical Faculty and University Hospital DüsseldorfHeinrich Heine University Düsseldorf40225DüsseldorfGermany Institut Necker-Enfants Malades(INEM) UniversitéParis CitéINSERM UMR-S1151CNRS UMR-S8253ParisFrance

In a recent study published in Nature,Nobs and colleagues aimed to identify novel mechanisms that may explain why diabetes is associated with an increased susceptibility to viral respiratory *** analyses revealed a central role of lung dendritic cells(DC)which exhibited several functional defects induced by hyperglycaemia and consequently result in impaired antiviral immune responses.

关键词： impaired lung respiratory