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Symptom presentation and evolution in the first 48 hours after injury are associated with return to play after concussion in elite Rugby Union

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Journal of Sport and Health Science 2024年第3期13卷 387-397页

作者： Ross Tucker Matt Cross Keith Stokes Lindsay Starling Rosy Hyman simon Kemp Stephen West Martin Raftery Eanna Falvey James Brown Institute of Sport and Exercise Medicine(ISEM) Department of ExerciseUniversity of StellenboschTygerberg 7505South Africa World Rugby Ltd. Dublin D02 AE93Ireland Premiership Rugby London SW1V 1PXUK Centre for Health and Injury and Illness Prevention in SportUniversity of BathClaverton Down BA27AYUK UK Collaborating Centre on Injury and Illness Prevention in Sport(UKCCIIS) University of BathClaverton Down BA27AYUK Rugby Football Union London TW27BAUK London School of Tropical Medicine London WC1E 7HTUK Sport Injury Prevention Research Centre Faculty of KinesiologyUniversity of CalgaryCalgary T2N 1N4Canada Department of Medicine School of Medicine and HealthUniversity College CorkCork T12 EC8PIreland Carnegie Applied Rugby Research(CARR)centre Carnegie School of SportLeeds Beckett UniversityLeeds LS63QSUK

Background:Return to play(RTP)in elite rugby is managed using a 6-stage graduated RTP protocol,which can result in clearance to play within 1 week of *** aimed to explore how symptom,cognitive,and balance presentation and evolution during concussion screens 2 h(head injury assessment(HIA2)and 48 h(HIA3)after injury were associated with time to RTP)to identify whether a more conservative graduated RTP may be ***:A retrospective cohort study was conducted in 380 concussed rugby players from elite men’s rugby over 3 consecutive *** were classified as shorter or longer returns,depending on whether RTP occurred within 7 days(allowing them to be considered to play the match 1 week after injury)or longer than 8 days,***,cognitive,and balance performance during screens was assessed relative to baseline(normal or abnormal)and to the preceding screen(improving or worsening).Associations between sub-test abnormalities and RTP time were explored using odds ratios(OR,longer ***).Median day absence was compared between players with abnormal or worsening results and those whose results were normal or ***:Abnormal symptom results during screens 2 h and 48 h after concussion were associated with longer return time(HIA2:OR=2.21,95%confidence interval(95%CI):1.39-3.50;HIA3:OR=3.30,95%CI:1.89-5.75).Worsening symptom number or severity from the time of injury to 2 h and 48 h post-injury was associated with longer return(HIA2:OR=2.49,95%CI:1.36-4.58;HIA3:OR=3.34,95%CI:1.10-10.15).Median days absence was greater in players with abnormal symptom results at both HIA2 and *** and balance performance were not associated with longer return and did not affect median days ***:Symptom presentation and evolution within 48 h of concussion were associated with longer RTP *** may guide a more conservative approach to RTP,while still adhering to individualized concussion management principles.

关键词： Brain injury Concussion management General return to play Medical management

Photoelectrochemical Iron-Catalyzed C(sp^(3))-H Borylation of Alkanes in a Position-Selective Manner

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CCS Chemistry 2024年第6期6卷 1430-1438页

作者： Wen Wei Bin Wang simon L.Homölle Jinbin Zhu Yanjun Li Tristan von Münchow Isaac Maksso Lutz Ackermann Institut für Organische und Biomolekulare Chemie Georg-August-Universität Göttingen37077 Göttingen

Catalytic C-H borylation is of prime topical importance,since easily available feedstock chemicals can thereby be transformed into valuable transient functional groups in the absence of directing ***,we disclose an iron-catalyzed C(sp^(3))-H borylation of simple,non-prefunctionalized alkanes,providing access to value-added products in a single step by means of *** power of merging photo-and electrochemistry was mirrored by ample scope and exceedingly mild reaction ***,an outstanding position-selectivity in favor of primary C(sp^(3))-H proved viable within the photoelectrochemical borylation through a chemo-selective anodic overoxidation *** ferro-photoelectrochemistry strategy avoids toxic precious transition metals,enabling C(sp^(3))-H borylations in a site-selective fashion.

关键词： photoelectrocatalysis C(sp^(3))-H borylation iron catalysis position-selectivity chlorine radical

Mobility of Major and Trace Elements during the Bauxitization Processes in Ngaoundal Area (Adamawa Cameroon): Implication on Mining Perspectives

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Open Journal of Geology 2024年第1期14卷 81-100页

作者： André Sini Harouna Boukari Ondoa Augustin Désiré Balla Djetenbe Beral Salomon Wangmené Awé simon Djakba Basga Jean Pierre Nguetnkam Department of Mining Engineering School of Geology and Mining Engineering University of Ngaoundere Ngaoundere Cameroon Department of Mining Engineering and Environment School of Mining Industry and Geology University of Abdou-Moumouni Niamey Niger Department of Earth Sciences Faculty of Science University of Ngaoundere Ngaoundere Cameroon Department of Mining Engineering Saint Jerome Polytechnic Saint Jerome Catholic University Institute of Douala Douala Cameroon Institute of Agricultural Research for Development (IRAD) Garoua Cameroon

This study was focused to assess major and trace elements in bauxitic duricrusts from Ngaoundal and its surroundings in order to establish their mining interest. To this end, fieldworks, mineralogical and geochemical analyses were carried out. Four facies of duricrust were identified and characterized from the summit to the top of the slope of the Ngaoundal mountain: scoriaceous, pisolitic, nodular and massive. Mineralogical and geochemical analyses performed on 16 samples, revealed a significant concentration of Al2O3 mainly in the scoriaceous facies (over 45% in grade), moderate in Fe2O3 (averaging 23.69%) and SiO2 (averaging 21.7%). Trace elements were generally low, excluding Cr (421 ppm on average), Zr (327 ppm on average and v (213 ppm on average). In addition, the limited quantities of alkalis (Na2O, K2O) and alkaline earths metals (MgO, CaO) coupled with the very high values of Chemical Index of Alteration (CIA) and Mineralogical Index of Alteration (MIA), (more than 99%) attest to the intense weathering of the studied materials. Allitization and monosiallitization constituted the crystallochemical phenomena that have led to the development of bauxitic minerals. More than 90% of gibbsite in scoriaceous facies, 52.21% - 76.01% of kaolinite in pisolitic facies and more than 40% of hematite in nodular facies were quantified. The relationships between the constitutive components indicated their interdependency during the bauxitization phenomenon. The mineralogical and geochemical properties highlighted the mining interest of the studied duricrusts to be valorized.

关键词： Duricrust Bauxitization Phenomenon Mineralogical and Geochemical Characterization Major and Trace Elements Mining Potential

Effect of Surfactants on the Thermoelectric Performance of Double-Walled Carbon Nanotubes

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Energy & Environmental Materials 2023年第1期6卷 274-280页

作者： Zakaria Saadi simon G.King Jose v.Anguita vlad Stolojan S.Ravi P.Silva Department of Electrical and Electronic Engineering Advanced Technology InstituteUniversity of SurreyGuildford GU27XHUK

Thermoelectrics are a promising solution to the recovery of some of the 60%of the worldwide energy wasted as ***,their conversion efficiency is low and the best performing materials are brittle,toxic,and made of expensive *** challenge in developing better performing materials is in disrupting the electrical vs thermal conductivity correlation,to achieve low thermal conductivity simultaneously with a high electrical *** nanotubes allow for the decoupling of the electronic density of states from the phonon density of states and this paper shows that flexible,thin films of double-walled carbon nanotube(DWCNT)can form effective n-and p-doped semiconductors that can achieve a combined Seebeck coefficient of 157.6µv K^(−1),the highest reported for a single DWCNT device to *** is achieved through selected surfactant doping,whose role is correlated with the length of the hydrocarbon chain of the hydrophobic tail group of the surfactant’s *** functionalized with Triton X-405 show the highest output power consisting of a single junction of p-and n-type thermoelectric elements,reaching as high as 67 nW for a 45 K temperature *** enabling flexible,cheaper,and more efficient thermoelectric generators through the use of functionalized CNTs.

关键词： carbon nanotubes DWCNT functionalization surfactant thermoelectric

Suppression of Self-Discharge in Aqueous Supercapacitor Devices Incorporating Highly Polar Nanofiber Separators

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Energy & Environmental Materials 2023年第3期6卷 74-86页

作者： Wesley G.Buxton simon G.King vlad Stolojan Advanced Technology Institute University of SurreyGuildford SurreyGU27XHUK

One of the major problems limiting the applications of electric double-layer(EDLC)supercapacitor devices is their inability to maintain their cell voltage over a significant ***-discharge is a spontaneous decay in charged energy,often resulting in fully depleted devices in a matter of ***,a new method for suppressing this self-discharge phenomenon is proposed by using directionally polarized piezoelectric electrospun nanofiber films as separator *** engineering of polyvinylidene fluoride(PvDF)nanofiber films containing a small concentration of sodium dodecyl sulfate(SDS)results in a high proportion of polarβphases,reaching 380.5%of the total *** polarity into the separator material provides a reverse-diode mechanism in the device,such that it drops from an initial voltage of 1.6 down to 1 v after 10 h,as opposed to 0.3 v with a nonpolarized,commercial separator ***,the energy retained for the polarized separator is 37%and 4%for the nonpolarized separator,making supercapacitors a more attractive solution for long-term energy storage.

关键词： piezoelectric polar nanofibers PvDF separators self-discharge supercapacitors

Machine learning potentials for metal-organic frameworks using an incremental learning approach

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npj Computational Materials 2023年第1期9卷 2147-2154页

作者： Sander vandenhaute Maarten Cools-Ceuppens simon DeKeyser Toon verstraelen veronique van Speybroeck Center for Molecular Modeling Ghent UniversityTechnologiepark 469052 ZwijnaardeBelgium

Computational modeling of physical processes in metal-organic frameworks(MOFs)is highly challenging due to the presence of spatial heterogeneities and complex operating conditions which affect their *** functional theory(DFT)may describe interatomic interactions at the quantum mechanical level,but is computationally too expensive for systems beyond the nanometer and picosecond ***,we propose an incremental learning scheme to construct accurate and data-efficient machine learning potentials for *** scheme builds on the power of equivariant neural network potentials in combination with parallelized enhanced sampling and on-the-fly training to simultaneously explore and learn the phase space in an iterative *** only a few hundred single-point DFT evaluations per material,accurate and transferable potentials are obtained,even for flexible frameworks with multiple structurally different *** incremental learning scheme is universally applicable and may pave the way to model framework materials in larger spatiotemporal windows with higher accuracy.

关键词： framework incremental neural

High Q and sub-wavelength THz electric field confinement in ultrastrongly coupled THz resonators

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光子学研究:英文版 2023年第7期11卷 1203-1216页

作者： simon MESSELOT SOLEN COEYMANS JEROME TIGNON SUKHDEEP DHILLON JULIETTE MANGENEY Laboratoire de Physique de l’Ecole Normale Supérieure Ecole normale supérieurePSL UniversitySorbonne UniversitéUniversitéParis DiderotSorbonne Paris CitéCNRS24 rue Lhomond75005 ParisFrance

The control of light–matter coupling at the single electron level is currently a subject of growing interest for the development of novel quantum devices and for studies and applications of quantum *** the terahertz(THz)spectral range,this raises the particular and difficult challenge of building electromagnetic resonators that can conciliate low mode volume and high quality ***,we report on hybrid THz cavities based on ultrastrong coupling between a Tamm cavity and an LC circuit metamaterial and show that they can combine high quality factors of up to Q=37 with a deep-subwavelength mode volume of v=3.2×10^(-4)λ^(3).Our theoretical and experimental analysis of the coupled mode properties reveals that,in general,the ultrastrong coupling between a metamaterial and a Fabry–Perot cavity is an effective tool to almost completely suppress radiative losses and,thus,ultimately limit the total losses to the losses in the metallic *** Tamm cavity-LC metamaterial coupled resonators open a route toward the development of single photon THz emitters and detectors and to the exploration of ultrastrong THz light–matter coupling with a high degree of coherence in the few to single electron limit.

关键词： coupling cavity coupled

Spin-polarized electron beam generation in the colliding-pulse injection scheme

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Matter and Radiation at Extremes 2023年第6期8卷 49-62页

作者： Zheng Gong Michael J.Quin simon Bohlen Christoph HKeitel Kristjan Põder Matteo Tamburini Max-Planck-Institut für Kernphysik Saupfercheckweg 169117 HeidelbergGermany Deutsches Elektronen-Synchrotron DESY Notkestr.8522607 HamburgGermany

Employing colliding-pulse injection has been shown to enable the generation of high-quality electron beams from laser-plasma ***,by using test particle simulations,Hamiltonian analysis,and multidimensional particle-in-cell simulations,we lay the theoretical framework for spin-polarized electron beam generation in the colliding-pulse injection ***,we show that this scheme enables the production of quasi-monoenergetic electron beams in excess of 80%polarization and tens of pC charge with commercial 10-TW-class laser systems.

关键词： polarized scheme enable

Periodicities in Solar Activity, Solar Radiation and Their Links with Terrestrial Environment

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Natural Science 2023年第3期15卷 111-147页

作者： valentina v. Zharkova Irina vasilieva simon J. Shepherd Elena Popova Department of MPEE University of Northumbria Newcastle upon Tyne UK ZvS Research Enterprise Ltd. London UK Department of Solar Physics Main Astronomical Observatory Kyiv Ukraine PRIMAL Research Group Sorbonne Universite Paris France Centro de Investigación en Astronomía Universidad Bernardo O’Higgins Santiago Chile

Solar magnetic activity is expressed via variations of sunspots and active regions varying on different timescales. The most accepted is an 11-year period supposedly induced by the electromagnetic solar dynamo mechanism. There are also some shorter or longer timescales detected: the biennial cycle (2 - 2.7 years), Gleisberg cycle (80 - 100 years), and Hallstatt’s cycle (2100 - 2300 years). Recently, using Principal Component Analysis (PCA) of the observed solar background magnetic field (SBMF), another period of 330 - 380 years, or Grand Solar Cycle (GSC), was derived from the summary curve of two eigenvectors of SBMF. In this paper, a spectral analysis of the averaged sunspot numbers, solar irradiance, and the summary curve of eigenvectors of SBMF was carried out using Morlet wavelet and Fourier transforms. We detect a 10.7-year cycle from the sunspots and modulus summary curve of eigenvectors as well a 22-year-cycle and the grand solar cycle of 342 - 350-years from the summary curve of eigenvectors. The Gleissberg centennial cycle is only detected on the full set of averaged sunspot numbers for 400 years or by adding a quadruple component to the summary curve of eigenvectors. Another period of 2200 - 2300 years is detected in the Holocene data of solar irradiance measured from the abundance of 14C isotope. This period was also confirmed with the period of about 2000 - 2100 years derived from a baseline of the solar background magnetic field, supposedly, caused by the solar inertial motion (SIM) induced by the gravitation of large planets. The implication of these findings for different deposition of solar radiation into the northern and southern hemispheres of the Earth caused by the combined effects of the solar activity and solar inertial motion on the terrestrial atmosphere is also discussed.

关键词： Sun: Magnetic Field Sun: Solar Activity Sun: Sunspots Sun: Solar Dynamo