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Science China Chemistry 2018年第8期61卷 909-924页

作者： Franziska K.Merkt thomas j.j.Müller Institute of Organic Chemistry and Macromolecular Chemistry Heinrich Heine University Düsseldorf

Expanded 5-(hetero)aryl-thien-2-yl substituted 3-ethynyl quinoxaline dyes with variable substitution pattern on the peripheral thiophene ring were synthesized in moderate to very good yields by Suzuki and Buchwald-Hartwig coupling of the corresponding brominated 3-ethynyl quinoxalines. Dumbbell-shaped bis(thienyl 3-ethynyl quinoxalines) are also accessible by the Suzuki protocol. The photophysical properties were investigated by UV and fluorescence spectroscopy. Most of the obtained compounds display fluorescence in solution and some of them also in the solid state. Additionally, tuning of the emission color of the quinoxaline based chromophores can be conveniently accomplished by the remote substituent group. The determined absorption and emission maximum as well as the Stokes shifts strongly correlate with Hammett σp+parameters. Besides,photophysical properties of selected derivatives in the solid state, biphasic solutions, and PMMA films, along with their relationships, are comparatively investigated. Moreover, two 5-(hetero)aryl-thien-2-yl substituted 3-ethynyl quinoxaline dyes are aggregation induced emission(AIE) chromophores indicated by restriction of molecular motions. A covalently restricted 3-ethynyl quinoxaline supports that the inhibition of molecular rotation is responsible for the significant enhancement of fluorescence in acetonitrile/water mixtures.

关键词：电子性质异种荧光光谱学合成特征 Stokes 颜色调节 PMMA

Laser wakefield accelerator modelling with variational neural networks

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High Power Laser Science and Engineering 2023年第1期11卷 67-74页

作者： M.j.V.Streeter C.Colgan C.C.Cobo C.Arran E.E.Los r.Watt N.Bourgeois L.Calvin j.Carderelli N.Cavanagh S.j.D.Dann r.Fitzgarrald E.Gerstmayr A.S.joglekar B.Kettle P.Mckenna C.D.Murphy Z.Najmudin P.Parsons Q.Qian P.P.rajeev C.P.ridgers D.r.Symes A.G.r.thomas G.Sarri S.P.D.Mangles School of Mathematics and Physics Queen’s University BelfastBelfastUK The john Adams Institute for Accelerator Science Imperial College LondonLondonUK York Plasma Institute School of PhysicsEngineering and TechnologyUniversity of YorkYorkUK Central Laser Facility STFC Rutherford Appleton LaboratoryDidcotUK Gérard Mourou Center for Ultrafast Optical Science University of MichiganAnn ArborUSA Ergodic LLC San FranciscoUSA Department of Physics SUPAUniversity of StrathclydeGlasgowUK

A machine learning model was created to predict the electron spectrum generated by a GeV-class laser wakefield *** model was constructed from variational convolutional neural networks,which mapped the results of secondary laser and plasma diagnostics to the generated electron *** ensemble of trained networks was used to predict the electron spectrum and to provide an estimation of the uncertainty of that *** is anticipated that this approach will be useful for inferring the electron spectrum prior to undergoing any process that can alter or destroy the *** addition,the model provides insight into the scaling of electron beam properties due to stochastic fluctuations in the laser energy and plasma electron density.

关键词： laser plasma interactions particle acceleration neural networks machine learning

Plasmonic organic electrochemical transistors for enhanced sensing

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Nano research 2023年第2期16卷 3201-3206页

作者： jinxin Li Foram Madiyar Sahil Ghate Kowsik Sambath Kumar jayan thomas CrEOL The College of Optics and PhotonicsUniversity of Central FloridaOrlandoFL 32816USA NanoScience Technology Center University of Central FloridaOrlandoFL 32816USA Aerospace Boulevard Embry-Riddle Aeronautical UniversityDaytona BeachFL 32114USA Department of Materials Science and Engineering University of Central Florida OrlandoFL 32816USA

Organic electrochemical transistors(OECTs)have been hailed as highly sensitive biomolecular sensors among organic electronic devices due to their superior stability in an aqueous environment and high *** the same time,plasmon based sensors are known to provide high sensitivity for biosensing due to the highly localized plasmonic *** we report a plasmonic OECT(POET)device that synchronizes the advantages of OECTs and plasmonic sensors on a single *** platform is fabricated by a simple,cost-effective,and high-throughput nanoimprinting process,which allows plasmonic resonance peak tuning to a given visible wavelength of interest for versatile *** glucose sensing as proof,a five-times sensitivity enhancement is obtained for POET compared to a regular(non-plasmonic)***,the POET paves the way to a new paradigm of optoelectronic sensors that combines the inherent high sensitivity of OECTs and localized plasmonic field to sense a vast realm of biomolecules.

关键词： organic electrochemical transistors(OECTs) plasmonics nanoimprint fabrication glucose sensing plasmonic biosensing

A Systematic review of the Genetic Predisposition to Injury in Football

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journal of Science in Sport and Exercise 2023年第2期5卷 97-115页

作者： Alexander B.T.McAuley David C.Hughes Loukia G.Tsaprouni Ian Varley Bruce Suraci thomas r.roos Adam j.Herbert Daniel T.jackson Adam L.Kelly Faculty of Health Education and Life SciencesBirmingham City UniversityBirminghamWest MidlandsUK Department of Sport Science Nottingham Trent UniversityNottinghamUK Academy Coaching Department AFC BournemouthBournemouthUK The International Academy of Sports Science and Technology(AISTS) University of LausanneLausanneSwitzerland Department of Life Sciences Birmingham City UniversityCity South CampusWestbourne RoadEdgbaston B153TNUK

Purpose Synthesise genetic association studies investigating injury involving football players to identify which genetic variants have the most empirical evidence to *** A comprehensive search of the PubMed,SPOrTDiscus,and MEDLINE databases until March 11th 2022 identi-fied 34 *** criteria:primary investigations,included football players,examined the association of a genetic variant with injury,and were published in *** of bias was assessed using the Newcastle–Ottawa Scale.A narrative synthesis summarised *** There were 33 candidate gene studies and one genome-wide study,with 9642 participants across all studies(range=43–1311;median=227).Ninety-nine polymorphisms were assessed within 63 ***-one polymorphisms were associated with injury *** polymorphisms had their specific allelic associations with injury replicated twice in independent cohorts:ACTN3(rs1815739)XX genotype was associated with an increased susceptibility to non-contact muscle injuries,ACAN(rs1516797)G allele was associated with increased susceptibility to anterior cruciate ligament(ACL)injuries,and VEGFA(rs2010963)CC genotype was associated with an increased susceptibility to ACL and ligament or tendon ***,several methodological issues(e.g.,small sample sizes,cohort heterogeneity,and population stratification)are prevalent that limit the reliability and external validity of *** At present,the evidence base supporting the integration of genetic information as a prognostic or diagnosis tool for injury risk in football is *** participation of organisations in international consortia is suggested to combat the current methodological issues and subsequently improve clarity concerning the underlying genetic contribution to injury susceptibility.

关键词： Soccer Genomics Polymorphism Snp Susceptibility

Quantitative model evaluation of organic carbon oxidation hypotheses for the Ediacaran Shuram carbon isotopic excursion

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Science China Earth Sciences 2017年第12期60卷 2118-2127页

作者： SHI Wei LI Chao thomas j.ALGEO State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences State Key Laboratory of Geological Processes and Mineral resources China University of Geosciences Department of Geology University of Cincinnati

The largest global carbon-cycle perturbation in Earth history was recorded in the Ediacaran—a persistent negative shift in the global marine dissolved inorganic carbon(DIC) reservoir that lasted for ~25–50 million years, with a nadir of –12‰(i.e.,the Shuram Excursion, or SE). This event is considered to have been a result of full or partial oxidation of a large dissolved organic carbon(DOC) reservoir, which, if correct, provides evidence for massive DOC storage in the Ediacaran ocean owing to an intensive microbial carbon pump(MCP). However, this scenario was recently challenged by new hypotheses that relate the SE to oxidization of recycled continentally derived organic carbon or hydrocarbons from marine seeps. In order to test these competing hypotheses,this paper numerically simulates changes in global carbon cycle fluxes and isotopic compositions during the SE, revealing that:(1) given oxygen levels in the Ediacaran atmosphere-ocean of ≤40% PAL, the recycled continental organic carbon hypothesis and the full oxidation of oceanic DOC reservoir hypothesis are challenged by the atmospheric oxygen availability which would have been depleted in 4 and 6 million years, respectively;(2) the marine-seep hydrocarbon oxidation hypothesis is challenged by the exceedingly large hydrocarbon fluxes required to sustain the SE for >25 Myr; and(3) the heterogeneous(partial) DOC oxidation hypothesis is quantitatively able to account for the SE because the total amount of oxidants needed for partial oxidation(reservoir could have been met.

关键词： Carbon isotope Shuram Excursion Dissolved organic carbon Atmospheric oxygen Oceanic oxidation

The lncrNA MArS modulates the epigenetic reprogramming of the marneral cluster in response to ABA

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Molecular Plant 2022年第5期15卷 840-856页

作者： thomas roulé Aurelie Christ Nosheen Hussain Ying Huang Caroline Hartmann Moussa Benhamed jose Gutierrez-Marcos Federico Ariel Martin Crespi thomas Blein UniversitéParis-Saclay CNRSINRAEUniversitéEvryInstitute of Plant Sciences Paris-Saclay(IPS2)91190 Gif-sur-YvetteFrance Universitéde Paris Institute of Plant Sciences Paris-Saclay(IPS2)91190 Gif-sur-YvetteFrance Instituto de Agrobiotecnología del Litoral CONICETFBCBUniversidad Nacional del LitoralColectora Ruta Nacional 168 km 03000 Santa FeArgentina School of Life Sciences University of WarwickCoventry CV47ALUK

Clustered organization of biosynthetic non-homologous genes is emerging as a characteristic feature of plant *** co-regulation of clustered genes seems to largely depend on epigenetic reprogram-ming and three-dimensional chromatin *** this study,we identified the long non-coding rNA(lncrNA)MArneral Silencing(MArS),localized inside the Arabidopsis marneral cluster,which con-trols the local epigenetic activation of its surrounding region in response to abscisic acid(ABA).MArS modulates the POLYCOMB rEPrESSIVE COMPLEX 1(PrC1)component LIKE HETErOCHrOMATIN PrOTEIN 1(LHP1)binding throughout the cluster in a dose-dependent manner,determining H3K27me3 deposition and chromatin *** response to ABA,MArS decoys LHP1 away from the cluster and promotes the formation of a chromatin loop bringing together the MArNErAL SYNTHASE 1(MrN1)locus and a distal ABA-responsive *** enrichment of co-regulated lncrNAs in clustered meta-bolic genes in Arabidopsis suggests that the acquisition of novel non-coding transcriptional units may constitute an additional regulatory layer driving the evolution of biosynthetic pathways.

关键词： lncrNA enhancer cluster chromatin conformation LHP1 ABA seed germination epigenetics marneral

Long-lived Nb-Ta mineralization in Mufushan,NE Hunan,South China:Geological,geochemical,and geochronological constraints

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Geoscience Frontiers 2023年第1期14卷 310-326页

作者： Nuerkanati Madayipu Huan Li thomas j.Algeo Safiyanu Muhammad Elatikpo rub'son N'nahano Heritier Hou-Xiang Zhou Han Zheng Qian-Hong Wu Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring(Central South University) Ministry of EducationChangsha 410083China School of Geosciences and Info-Physics Central South UniversitySouth Lushan RoadChangsha 410083China State Key Laboratory of Geological Processes and Mineral resources School of Earth ResourcesChina University of GeosciencesWuhan 430074China State Key Laboratory of Biogeology and Environment Geology School of Earth SciencesChina University of GeosciencesWuhan 430074China Department of Geology University of CincinnatiCincinnatiOH 45221-0013 USA Hunan Provincial Institute of Land and resources Planning Changsha 410007China

The Mufushan Complex(MFSC),located in northeastern Hunan,is a significant producer of Nb-Ta-Li-Be rare metals in South *** present study examines the genetic relationship,material provenance,fluid evolution,and metallogeny of the co-developed ore-free pegmatite(OFP)and ore-bearing pegmatite(OBP)in granite-related pegmatite-type Nb-Ta rare-metal deposits in *** minerals(columbite-tantalite(coltan),zircon,and monazite)were chosen for *** coltan grains display both primary crystallization structures(crystal homogeneity,oscillatory zonings,and primary growth rims)resulting from equilibrium and disequilibrium reactions due to localized changes in the physicochemical conditions and environment,as well as later replacement structures(alteration rims,patches,irregular zonations,and complex zonations)from metasomatic replacement processes related to hydrothermal fluid *** coltan yielded two weighted mean^(206)Pb/^(238)U ages of 138.1±2.1 Ma and 125.3±2.0 Ma corresponding to magmatic and hydrothermal Nb-Ta mineralization *** the OFP,zircons also yielded two weighted mean^(206)Pb/^(238)U ages of 138.4±0.8 Ma and 131.5±0.7 Ma,whereas monazite gave a weighted mean U-Pb age 142.9±1.2 *** ages of 142-138 Ma and 131 Ma represent the early and late stages of OFP crystallization and barren pegmatites in the MFSC,*** Lu-Hf isotopic compositions link rare-metal metallogenesis to the Lengjiaxi Group,which was the source material to the Mufushan composite ***ε_(Hf)(t)values and TDM2 ages from the OFP(-7.6 to-3.6 and 1676-1418 Ma,respectively)and the OBP(-14.1 to+4.9 and 2976-1548 Ma,respectively)are akin to those of schists and metasandstones of the metasedimentary Lengjiaxi *** propose a long-lived(ca.13-Myr)event involving two metallogenic episodes of Nb-Ta mineralization in the Mufushan *** study demonstrates the potential of zircon,coltan,and monazite for fingerprinting minerals and classifying the m

关键词： Zircon Coltan Monazite Fluid evolution Pegmatite rare-metal deposit

The impact of macroalgae on mean and turbulent flow fields

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journal of Hydrodynamics 2015年第3期27卷 427-435页

作者： thomas robert E. MCLELLAND Stuart j. Department of Geography Environment and Earth Sciences University of Hull

In this paper, we attempt to quantify the mean and turbulent flow fields around live macroalgae within a tidal inlet in Norway. Two Laminaria digitata specimens - 0.50 m apart were selected for detailed study and a profiling ADV was used to collect 45 velocity profiles, each composed of up to seven 0.035 m-high profiles collected for 240 s at 100 Hz, at a streamwise spacing of 0.25 m and cross-stream spacing of 0.20 m. To quantify the impact of the macroalgae, measurements were repeated over a sparser grid after the region had been completely cleared of algae and major roughness elements.

关键词： dealiasing laminaria digitata turbulence vectrino profiler velocity profile

Effects of contact/collision sport history on gait in early-to mid-adulthood

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journal of Sport and Health Science 2023年第3期12卷 398-405页

作者： Katherine j.Hunzinger jaclyn B.Caccese rebekah Mannix William P.MeehanⅢ jocelyn F.Hafer C.Buz Swanik thomas A.Buckley Department of Biostatistics Epidemiologyand InformaticsUniversity of Pennsylvania Perelman School of MedicinePhiladelphiaPA 19104USA Penn Injury Science Center University of PennsylvaniaPhiladelphiaPA 19104USA School of Health and rehabilitation Sciences The Ohio State University College of MedicineColumbusOH 43210USA Division of Emergency Medicine Boston Children's HospitalBostonMA 02115USA Departments of Pediatrics and Emergency Medicine Harvard Medical SchoolBostonMA 02115USA The Micheli Center for Sports Injury Prevention WalthamMA 02453USA Division of Sports Medicine Department of OrthopedicsBoston Children's HospitalBostonMA 02453USA Department of Pediatrics and Orthopedics Harvard Medical SchoolBostonMA 02453USA Department of Kinesiology and Applied Physiology University of DelawareNewarkDE 02453USA Interdisciplinary Program in Biomechanics and Movement Science University of DelawareNewarkDE 02453USA

Background:To determine the effect of contact/collision sport participation on measures of single-task(ST)and dual-task(DT)gait among early-to middle-aged ***:The study recruited 113 adults(34.88±11.80 years,(mean±SD);53.0%female)representing 4 *** included(a)former non-contact/collision athletes and non-athletes who are not physically active(n=28);(b)former non-contact/collision athletes who are physically active(n=29);(c)former contact/collision sport athletes who participated in high-risk sports and are physically active(n=29);and(d)former rugby players with prolonged repetitive head impact exposure history who are physically active(n=27).Gait parameters were collected using inertial measurement units during ST and DT *** cost was calculated for all gait parameters(double support,gait speed,and stride length).Groups were compared first using one-way analysis of *** a multiple regression was performed for participants in the highrisk sport athletes and repetitive head impact exposure athletes groups only to predict gait outcomes from contact/collision sport career ***:There were no significant differences between groups on any ST,DT,or DT cost outcomes(p>0.05).Contact/collision sport duration did not predict any ST,DT,or DT cost gait ***:Years and history of contact/collision sport participation does not appear to negatively affect or predict neurobehavioral function in early-to mid-adulthood among physically active individuals.

关键词： Exercise Neurodegenerative disease Postural control rugby Subconcussive impacts

Analysis of PFAAs in American alligators part 2： Potential dietary exposure of South Carolina hunters from recreationally harvested alligator meat

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journal of Environmental Sciences 2017年第11期29卷 31-38页

作者： jessica j.Tipton Louis j.Guillette jr Susan Lovelace Benjamin B.Parrott thomas r.rainwater jessica L.reiner College of Charleston Charleston SC 29724 USA Medical University of South Carolina Department of Obstetrics and Gynecology Charleston SC 29425 USA University of Georgia Odum School of Ecology Savannah River Ecology Laboratory Jackson SC 29831 USA Torn Yawkey Wildlife Center & Belle W. Baruch Institute of Coastal Ecology and Forest Science Clemson University P.O. Box 59(5 Georgetown SC 29442 USA National Institute of Standards and Technology Chemical Sciences Division Hollings Marine Laboratory Charleston SC 29412 USA

Exposure to perfluorinated alkyl acids（PFAAs） has been linked to many harmful health effects including reproductive disorders, developmental delays, and altered liver and kidney function. Most human exposure to environmental contaminants, including PFAAs,occurs through consumption of contaminated food or drinking water. This study uses PFAA data from meat samples collected from recreationally harvested American alligators（Alligator mississippiensis） in South Carolina to assess potential dietary exposure of hunters and their families to PFAAs. Consumption patterns were investigated using intercept surveys of 23 hunters at a wild game meat processor. An exposure scenario using the average consumption frequency, portion size, and median perfluorooctane sulfonic acid（PFOS） concentration in alligator meat from all hunt units found the daily dietary exposure to be 2.11 ng/kg body weight per day for an adult human. Dietary PFOS exposure scenarios based on location of harvest suggested the highest daily exposure occurs with alligator meat from the Middle Coastal hunt unit in South Carolina. Although no samples were found to exceed the recommended threshold for no consumption of PFOS found in Minnesota state guidelines, exposure to a mixture of PFAAs found in alligator meat and site-specific exposures based on harvest location should be considered in determining an appropriate guideline for vulnerable populations potentially exposed to PFAAs through consumption of wild alligator meat.

关键词： Public hunt American alligator Dietary exposure PFOS Consumption advisory Contaminant consumption