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Foam rolling and stretching do not provide superior acute flexibility and stiffness improvements compared to any other warm-up intervention: A systematic review with meta-analysis

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Journal of Sport and health Science 2024年第4期13卷 509-520页

作者： Konstantin Warneke Gerit Plöschberger Lars h.lohmann Eric Lichtenstein Daniel Jochum Stanislav D.Siegel Astrid Zech David G.Behm Institute of Sport Science University of KlagenfurtKlagenfurt am Wörthersee 9020Austria Department of human Motion Science and Exercise Physiology Friedrich Schiller UniversityJena 07749Germany Department Sport Exercise and HealthUniversity of BaselBasel 4052Switzerland Department of health Sciences and Technology ETH ZurichZurich 8092Switzerland School of human Kinetics and Recreation Memorial University of NewfoundlandSt.JohnsNL A1C 5S7Canada

Background:Acute improvement in range of motion(ROM)is a widely reported effect of stretching and foam rolling,which is commonly explained by changes in pain threshold and/or musculotendinous ***,these effects were also reported in response to various other active and passive interventions that induce responses such as enhanced muscle ***,we hypothesized that acute ROM enhancements could be induced by a wide variety of interventions other than stretching or foam rolling that promote an increase in muscle ***:After a systematic search in PubMed,Web of Science,and SPORTDiscus databases,38 studies comparing the effects of stretching and foam rolling with several other interventions on ROM and passive properties were *** studies had 1134 participants in total,and the data analysis resulted in 140 effect sizes(ESs).ES calculations were performed using robust variance estimation model with ***:Study quality of the included studies was classified as fair(PEDro score=4.58)with low to moderate certainty of *** showed no significant differences in ROM(ES=0.01,p=0.88),stiffness(ES=0.09,p=0.67),or passive peak torque(ES=-0.30,p=0.14)between stretching or foam rolling and the other identified *** plots revealed no publication ***:Based on current literature,our results challenge the established view on stretching and foam rolling as a recommended component of warm-up *** lack of significant difference between interventions suggests there is no need to emphasize stretching or foam rolling to induce acute ROM,passive peak torque increases,or stiffness reductions.

关键词： Range of motion Passive properties Muscletendon unit Muscle tissue

Energy enhancement of laser-driven ions by radiation reaction and Breit-Wheeler pair production in the ultra-relativistic transparency regime

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high Power Laser Science and Engineering 2024年第1期12卷 60-73页

作者： Shikha Bhadoria Mattias Marklund christoph h.Keitel Max-Planck-Institut für Kernphysik HeidelbergGermany Department of Physics University of GothenburgGöteborgSweden

The impact of radiation reaction and Breit±Wheeler pair production on the acceleration of fully ionized carbon ions driven by an intense linearly polarized laser pulse has been investigated in the ultra-relativistic transparency *** initial expectations, the radiation reaction and pair production at ultra-high laser intensities are found to enhance the energy gained by the ions. The electrons lose most of their transverse momentum, and the additionally produced pair plasma of Breit±Wheeler electrons and positrons co-streams in the forward direction as opposed to the existing electrons streaming at an angle above zero degree. We discuss how these observations could be explained by the changes in the phase velocity of the Buneman instability, which is known to aid ion acceleration in the breakout afterburner regime, by tapping the free energy in the relative electron and ion streams. We present evidence that these non-classical effects can further improve the highest carbon ion energies in this transparency regime.

关键词： ion acceleration quantum electrodynamic effects

Optical probing of ultrafast laser-induced solid-to-overdense-plasma transitions

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Light(Science & Applications) 2024年第5期13卷 973-984页

作者： Yasmina Azamoum Georg Alexander Becker Sebastian Keppler Guillaume Duchateau Stefan Skupin Mickael Grech Fabrice Catoire Sebastian hell Issa Tamer Marco hornung Marco hellwing Alexander Kessler Franck Schorcht Malte christoph Kaluza GSI helmholtzzentrum für Schwerionenforschung Planckstr.164291 DarmstadtGermany. helmholtz Institute Jena Fröbelstieg 307743 JenaGermany. Institute of Optics and Quantum Electronics Friedrich-SchillerUniversität JenaMax-Wien-Platz 107743 JenaGermany. CEA-CESTA 15 Avenue des SablièresCS6000133116 Le BarpCedexFrance Institut Lumière Matière UMR 5306-CNRSUniversitéde Lyon 169622 VilleurbanneFrance. LULI CNRSCEASorbonne UniversitéInstitut Polytechnique de ParisPalaiseauFrance. Universitéde Bordeaux-CNRS-CEA CELIAUMR 5107 TalenceFrance

Understanding the solid target dynamics resulting from the interaction with an ultrashort laser pulse is a challenging fundamental multi-physics problem involving atomic and solid-state physics,plasma physics,and laser *** of the initial interplay of the underlying processes is essential to many applications ranging from lowpower laser regimes like laser-induced ablation to high-power laser regimes like laser-driven ion *** the properties of the so-called pre-plasma formed as the laser pulse’s rising edge ionizes the target is complicated from the theoretical and experimental point of view,and many aspects of this laser-induced transition from solid to overdense plasma over picosecond timescales are still open *** the one hand,laser-driven ion acceleration requires precise control of the pre-plasma because the efficiency of the acceleration process crucially depends on the target properties at the arrival of the relativistic intensity peak of the *** the other hand,efficient laser ablation requires,for example,preventing the so-called“plasma shielding”.By capturing the dynamics of the initial stage of the interaction,we report on a detailed visualization of the pre-plasma formation and ***-thin diamond-like carbon foils are shown to transition from solid to plasma during the laser rising edge with intensitieshot near-infrared probe transmission measurements evidence sub-picosecond dynamics of an expanding plasma with densities above 10^(23)cm^(−3)(about 100 times the critical plasma density).The complementarity of a solid-state interaction model and kinetic plasma description provides deep insight into the interplay of initial ionization,collisions,and expansion.

关键词： laser acceleration solid

Production of the X(4014)as the Spin-2 Partner of X(3872)in e^(+)e^(-)Collisions

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Chinese Physics Letters 2024年第3期41卷 30-36页

作者： Pan-Pan Shi Vadim Baru Feng-Kun Guo christoph hanhart Alexey Nefediev CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Departamento de F′ısica Te′orica and IFIC Centro Mixto Universidad de Valencia-CSIC Institutos de Investigaci′on de PaternaAptdo.2208546071 ValenciaSpain Institut fur Theoretische Physik II Ruhr-Universitat BochumD-44780 BochumGermany Peng huanwu Collaborative Center for Research and Education Beihang UniversityBeijing 100191China Institute for Advanced Simulation Institut fur Kernphysik and Julich Center for Hadron PhysicsForschungszentrum JulichD-52425 JulichGermany Jozef Stefan Institute Jamova 391000LjubljanaSlovenia CeFEMA Center of Physics and Engineering of Advanced MaterialsInstituto Superior T′ecnicoAvenida Rovisco Pais 11049-001 LisboaPortugal

In 2021,the Belle collaboration reported the first observation of a new structure in theψ(2S)γfinal state produced in the two-photon fusion *** the hadronic molecule picture,this new structure can be associatedwith the shallow isoscalar D*D* bound state and as such is an excellent candidate for the spin-2 partner of the X(3872)with the quantum numbers J^(PC)=2^(++)conventionally named X_(2).

关键词： process X(3872) Collisions

Age and petrogenesis of the newly discovered Early Permian granite in the Kumtor gold field， Kyrgyz Tien-Shan

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Journal of Earth Science 2024年

作者： Kyiazbek Asilbekov Rustam Orozbaev Etienne Skrzypek christoph hauzenberger Elena Ivleva Daniela Gallhofer Jian-Feng Gao Nikolay Pak Anatoliy Shevkunov Anatoliy Bashkirov Aizat Zhaanbaeva Institute of Geology， National Academy of Sciences of the Kyrgyz Republic Institute of Earth Sciences， University of Graz State Key Laboratory of Ore Deposit Geochemistry， Institute of Geochemistry， Chinese Academy of Sciences Kumtor Gold Company CJSC

Permian intrusions are widespread in the Middle and Southern Tien Shan， with fewer occurrences in the Northern Tien-Shan. Notably， many of these intrusions are spatially associated with a variety of ore deposits， indicating a significant link between magmatic activity and mineralization processes in these areas. We studied granite samples recently recovered from drilling in the Kumtor gold field to evaluate their potential relationships with gold mineralization. We report major and trace element geochemistry， zircon U-Pb age and hf isotope data for this so-called Kumtor granite. The Kumtor granite is metaluminous to peraluminous and belongs to the high-K and calc-alkaline series with I-type geochemical characteristics. The relatively high K2O and Na2O concentrations and low high field strength elements （hFSE） and heavy rare earth elements （hREE）， the presence of biotite within these I-type granites， together with their low zircon saturation temperatures （731–779 °C）， suggest that they were likely derived from a hydrous source formed by dehydration melting of mica-bearing， medium- to high-K metabasaltic rocks. Our zircon U-Pb dating results indicate that the Kumtor granite intruded at 293 ± 1.7 Ma， which is consistent with the age range of other Middle Tien-Shan granitoids. The zircon hf isotopic composition is εhf（t）= –7.56 to –5.05， indicating an ancient （1.39 to 1.52 Ga） crustal origin. Petrographical， geochemical and geochronological data indicate that the Kumtor granite is similar to leuco-granites of the Terekty complex. Our results indicate that the Kumtor granite was emplaced in the early Permian in a post-collision setting and may have temporal and genetic relationships with gold mineralization.

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Durable All Inorganic Perovskite Tandem Photovoltaics

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Durable All Inorganic Perovskite Tandem Photovoltaics

Quenching Simulation of PM Coated Tools

第十一届新型太阳能材料科学与技术学术研讨会

作者： Chenghao Duan Kaicheng Zhang christoph J.Brabec Feng Gao Keyou Yan School of Environment and Energy South China University of Technology

Inorganic perovskite tandem solar cells（IPTSCs） are promising candidates to break the efficiency bottleneck and address the stability issue.[1,2] however,challenges remain in fabricating 2-terminal（2T） IPTSCs due to the inferior film formation and deep trap states induced by tin cations.[3] herein,a green ligand evolution（GLE） strategy with p-toluenesulfonyl hydrazide is employed to regulate film formation and eliminate deep traps in inorganic narrow bandgap perovskite,enabling the successful development of 2T ***,the 1.31 eV CsPbSnI:GLE device delivers a record efficiency of 17.41%.Combined with the 1.92 eV CsPbIBr top-cell,2T-IPTSCs exhibit a champion efficiency of 22.57%（certified 21.92%）.Additionally,IPTSCs are engineered to deliver remarkable operation durability under maximum power point tracking,maintaining 80% of the initial efficiency at 65 ℃ for 1510 h and 85℃ for 800 h,respectively.

关键词： Inorganic perovskite Tandem solar cell Narrow bandgap Green Ligand Evolution Durability

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材料热处理学报 2004年第5B期25卷 752-757页

作者： Axel htter Werner Theisen christoph Broeckmann Chair of Materials Technology Ruhr University Bochum GermanyChair of Materials Technology Ruhr University Bochum GermanyKoppern Entwicklungs-GmbH Hattingen Germany

hIP cladding is a powder metallurgical coating technique used in the production of wear parts and tools. In many cases the composite components consist of carbide-free hot-work steel as base material and wear resistant carbide-rich PM cold-work steel as coating material. To ensure operativeness a heat treatment matched to the substrate and coating material is required. Dissimilar phase transformation behaviour and different thermal expansion coefficients of layer and substrate entail inner stresses affecting the transformation kinetics in turn. In order to get a deeper insight into these effects Finite Element simulation tools are used. On the one hand, the transient heat conduction problem of the quenching process has to be solved. Non-linear boundary conditions and phase transformation of both, substrate and layer are considered. On the other hand, the mechanical response is calculated. The overall aim of the investigation is an improvement of common heat treatment techniques used for hIP cladded wear parts.

关键词：数值模拟淬火 hIP包覆磨损工具钢

Advantages of Multi-body Simulation within the Design Process of heavy Drivetrains

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Journal of Mechanics Engineering and Automation 2014年第12期4卷 919-923页

作者： Jennifer Papies christoph lohmann Jorg hermes Markus Woppermann Ruhr University Bochum Bochum 44801 Germany SEW-EURODRIVE Gmbh & Co. KG Bruchsal 76646 Germany

For the further design of the particular gearbox components, the alternating cycles of the respective application mean an often insufficient knowledge of the actual loads occuring in use. Especially for the application within lifting units, such dynamic load cycles are very difficult to pre-estimate. The so-called slack rope test represents the most critical point in the load cycle and provides a special challenge for the gearbox design. Because of this missing expert knowledge, a test bench of such an application is installed and applied to practical movement cycles. Besides the test bench, a multi-body simulation model of the whole system is mapped within the MBS （multi-body simulation） environment SIMPACK. To verify this simulation model, the results are compared with the respective measurements of the test bench. These comparisons show very good agreements. Thus, one of the major advantages of using such simulation tools is the possibility to re-evaluate the internal and external loads during the whole design process. Finally, these simulations serve as a clarification of the load spectrum of the different drivetrain components. Gearbox series or different modifications of the design can now be analyzed prospectively without extensive testing.

关键词： Comparison of test bench and simulation results dynamic behavior of lifting units multi-body simulation.

Treatment of early gastric cancer in the Western World

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World Journal of Gastroenterology 2014年第19期20卷 5672-5678页

作者： Elfriede Bollschweiler Felix Berlth christoph Baltin Stefan Mnig Arnulf h hlscher Department of General Visceral and Cancer SurgeryUniversity of Cologne50937 CologneGermany

The incidence rate of gastric cancer is much higher in Asia than in the Western industrial *** to the different screening programs in Japan and Korea about fifty percent of treated patients had an early tumor *** contrast,European and American patients with gastric cancer had an advanced tumor ***,the experience for the various therapeutic options for gastric cancer may be different between these *** this review we tried to point out the treatment modalities in Western industrial countries for early gastric cancer.

关键词： Gastric cancer Early cancer Epidemiology Diagnosis Therapy Western World