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The great catastrophe: causes of the permo-Triassic marine mass extinction

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National Science Review 2024年第1期11卷 37-50页

作者： paul b.Wignall David p.G.bond School of earth & environment University of Leeds School of environmental Sciences University of Hull

The marine losses during the permo-Triassic mass extinction were the worst ever experienced. All groups were badly affected, especially amongst the benthos(e.g. brachiopods, corals, bryozoans, foraminifers,ostracods). planktonic populations underwent a fundamental change with eukaryotic algae being replaced by nitrogen-fixing bacteria, green-sulphur bacteria, sulphate-reducing bacteria and prasinophytes. Detailed studies of boundary sections, especially those in South China, have resolved the crisis to a ～55 kyr interval straddling the permo-Triassic boundary. Many of the losses occur at the beginning and end of this interval painting a picture of a two-phase extinction. Improved knowledge of the extinction has been supported by numerous geochemical studies that allow diverse proposed extinction mechanisms to be studied. A transition from oxygenated to anoxic-euxinic conditions is seen in most sections globally, although the intensity and timing shows regional variability. Decreased ocean ventilation coincides with rapidly rising temperatures and many extinction scenarios attribute the losses to both anoxia and high *** kill mechanisms include ocean acidification for which there is conflicting support from geochemical proxies and, even less likely, siltation(burial under a massive influx of terrigenous sediment) which lacks substantive sedimentological evidence. The ultimate driver of the catastrophic changes at the end of the permian was likely Siberian Trap eruptions and their associated carbon dioxide emissions with consequences such as warming, ocean stagnation and acidification. Volcanic winter episodes stemming from Siberian volcanism have also been linked to the crisis, but the short-term nature of these episodes(ecades) and the overwhelming evidence for rapid warming during the crisis makes this an unlikely cause. Finally, whilst the extinction is well studied in equatorial latitudes, a different history is found in northern boreal latitudes

关键词： ocean anoxia ocean acidification siltation productivity collapse volcanic winter

RbC aggregation,deformation and adhesion to endothelium:Role of nitric oxide derived from L-Arginine and sodium nitroprusside

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Journal of Innovative Optical Health Sciences 2024年第5期17卷 53-65页

作者： M.K.Maksimov p.b.ermolinskiy O.N.Scheglovitova N.N.Sklyankina A.V.Muravyov A.e.Lugovtsov A.V.priezzhev Faculty of physics M.V.Lomonosov Moscow State University bld.1subbuilding.2Leninskie goryMoscow 11991Russia N.F.Gamaleya National Research Center for epidemiology and Microbiology 18 Gamaleya StreetMoscow 123098Russia K.D.Ushinsky Yaroslavl State pedagogical University 108/1 Respublikanskaya StreetYaroslavl 150000Russia

Red blood cells(RbCs)are the most abundant human blood *** aggregation and deformation strongly determine blood viscosity which impacts hemorheology and *** turn,RbC properties depend on di®erent endogenous and exogenous *** such factor is nitric oxide(NO),which is mainly produced by endothelial cells(eC)from L-arginine amino acid in the circulatory *** the mechanisms of the RbC-endothelium interplay are not clear up to date and considering its possible clinical importance,the aims of this study are to investigate in vitro:(1)The e®ect of L-arginine induced NO on RbC aggregation and adhesion to endothelium;(2)the NO e®ect on RbC aggregation and deformation induced by L-arginine and sodium nitroprusside without the presence of endothelium in the *** RbC aggregation and adhesion to a monolayer of eC were studied using optical tweezers(OT).The RbC deformability and aggregation without endothelium in the samples were studied using the°ow chamber method and Myrenne *** con¯rmed that NO increases deformability and decreases aggregation of *** showed that the soluble guanylate cyclase pathway appears to be the only NO signaling pathway *** the samples with the endothelium,the\bell-shaped"dependence of RbC aggregation force on L-arginine concentration was observed,which improves our knowledge about the process of NO production by ***,data related to L-arginine accumulation by endothelium were obtained:Necessity of the presence of extracellular L-arginine stated by other authors was put under *** our study,NO decreased the RbC-endothelium adhesion,however,the tendency appeared to be weak and was not con¯rmed in another set of *** our knowledge,this is the¯rst attempt to measure the forces of RbC adhesion to endothelium monolayer with OT.

关键词： Red blood cells aggregation L-arginine endothelium optical tweezers Myrenne flow chamber

Towards global coverage of gridded parameterization for CLImate GeNerator(CLIGeN)

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big earth Data 2024年第1期8卷 142-165页

作者： Andrew T.Fullhart Guillermo e.ponce-Campos Menberu b.Meles Ryan p.McGehee Haiyan Wei Gerardo Armendariz Shea burns David C.Goodrich Southwest Watershed Research Center USDA-ARS TucsonAZUSA School of Natural Resources and the environment University of ArizonaTucsonAZUSA Sustainable Agricultural Water Systems Unit USDA-ARS DavisCAUSA Agricultural and biosystems engineering Iowa State UniversityAmesIAUSA

Stochastic weather generators create time series that reproduce key weather dynamics present in long-term *** dataset detailed herein is a large-scale gridded parameterization for CLImate GeNerator(CLIGeN)that fills spatial gaps in the coverage of existing regional CLIGeN parameterizations,thereby obtaining near-global availability of combined *** dataset primarily covers countries north of 40°latitude with 0.25°spatial *** CLIGeN parameters were estimated based on 20-year records from four popular global climate *** parameters were statistically downscaled to estimate point-scale values,while point-scale temperature and solar radiation parameters were approximated by direct calculation from high-resolution *** parameter values were used in some cases,such as with wind ***-validation was done to assess the downscaling approach for six precipitation parameters using known point-scale values from ground-based CLIGeN *** parameter values were derived from daily accumulation records at 7,281 stations and high temporal resolution records at 609 *** sensitive parameters,monthly average storm accumulation and maximum 30-minute intensity,were shown have RMSe values of 1.48 mm and 4.67 mm hr^(−1),*** precipitation and the annual number of days with precipitation occurrence were both within 5%of ground-based parameterizations,effectively improving climate data availability.

关键词： Agriculture climate hydrology soil erosion stochastic weather generator

Highly enhanced UV absorption and light emission of monolayer WS_(2)through hybridization with Ti_(2)N MXene quantum dots and g-C_(3)N_(4)quantum dots

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Opto-electronic Advances 2024年第6期7卷 31-39页

作者： Anir S.Sharbirin Rebekah e.Kong Wendy b.Mato Trang Thu Tran eunji Lee Jolene W.p.Khor Afrizal L.Fadli Jeongyong Kim Department of energy Science Sungkyunkwan UniversitySuwon 16419Republic of Korea

Two-dimensional(2D)transition metal dichalcogenides(TMD)are atomically thin semiconductors with promising optoelectronic applications across the visible ***,their intrinsically weak light absorption and the low photoluminescence quantum yield(pLQY)restrict their performance and potential use,especially in ultraviolet(UV)wavelength light *** dots(QD)derived from 2D materials(2D/QD)provide efficient light absorption and emission of which energy can be tuned for desirable light *** this study,we greatly enhanced the photon absorption and pLQY of monolayer(1L)tungsten disulfide(WS_(2))in the UV range via hybridization with 2D/QD,particularly titanium nitride MXene QD(Ti_(2)N MQD)and graphitic carbon nitride QD(GCNQD).With the hybridization of MQD or GCNQD,1LWS_(2)showed a maximum pL enhancement by 15 times with 300 nm wavelength excitation,while no noticeable enhancement was observed when the excitation photon energy was less than the bandgap of the QD,indicating that UV absorption by the QD played a crucial role in enhancing the light emission of 1L-WS_(2)in our 0D/2D hybrid *** findings present a convenient method for enhancing the photo-response of 1L-WS_(2)to UV light and offer exciting possibilities for harvesting UV energy using 1L-TMD.

关键词： monolayer TMD WS_(2) 2D-derived quantum dots UV absorption energy transfer

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A systematic scoping review of study methodology for randomized controlled trials investigating probiotics in athletic and physically active populations

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Journal of Sport and Health Science 2024年第1期13卷 61-71页

作者： Alex e.Mohr David b.pyne Geovana Silva Fogaça Leite Deborah Akins Jamie pugh College of Health Solutions Arizona State UniversityPhoenixAZ 85004USA Research Institute for Sport and exercise University of CanberraCanberraACT 2617Australia Laboratory of Functional Fermented Food Faculty of Pharmaceutical SciencesUniversity of São PauloSão Paulo 05508-030Brazil Research Institute for Sport and exercise Sciences Liverpool John Moores UniversityLiverpool L33AFUK

background:The purported ergogenic and health effects of probiotics have been a topic of great intrigue among researchers,practitioners,and the lay public *** has also been an increased research focus within the realm of sports science and exercise medicine on the athletic gut ***,compared to other ergogenic aids and dietary supplements,probiotics present unique study *** objectives of this systematic scoping review were to identify and characterize study methodologies of randomized controlled trials investigating supplementation with probiotics in athletes and physically active ***:Four databases(MeDLINe,CINAHL,Cochrane CeNTRAL,and Cochrane Database of Systematic Reviews)were searched for randomized controlled studies involving healthy athletes or physically active *** intervention with probiotics and inclusion of a control and/or placebo group were *** peer-reviewed articles in english were considered,and there were no date *** were extracted and presented in tabular form to detail study protocols,characteristics,and *** in randomized controlled trials was determined with the Rob 2.0 ***:A total of 45 studies were included in the review,with 35 using a parallel group design and 10 using a cross-over *** half the studies used a single probiotic and the other half a multi-strain *** probiotic dose ranged from 2×10^(8)to 1×10^(11)colony forming units daily,and the length of intervention was between 7 and 150 *** than half the studies directly assessed gastrointestinal symptoms,gut permeability,or the gut *** sex ratio of participants was heavily weighted toward males,and only 3 studies exclusively investigated ***-level adverse events were reported in only 2 studies,although the methodology of reporting varied *** risk of bias was generally low,although details on randomization were lacking in some s

关键词： exercise experimental methodology Gastrointestinal symptoms Gut microbiota probiotic supplementation

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Chromomagnetic dipole moments of light quarks in the bestest little Higgs model

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Chinese physics C 2024年第10期48卷 125-136页

作者： T.Cisneros-pérez e.Cruz-Albaro A.Y.Ojeda-Castañeda S.e.Solís-Núñez Unidad Académica de Ciencias Químicas Universidad Autónoma de ZacatecasApartado Postal C-58598060 ZacatecasMexico Facultad de Física Universidad Autónoma de ZacatecasApartado Postal C-58098060 ZacatecasMexico

In this study,we investigated the anomalous Chromomagnetic Dipole Moment(CMDM),denoted as μ_(q)^(bLHM),of light quarks q=(u,c,d,s,b) within the framework of the bestest Little Higgs Model(bLHM)as an extension of the Standard Model(SM).Our investigation encompassed novel interactions among the light quarks,heavy quark b,and heavy bosons (W'^(±),H^(±),φ^(±),η^(±))incorporating the extended Cabibbo-Kobayashi-Maskawa(CKM)matrix characteristic of the *** thoroughly explored the permissible parameter space,yielding a spectrum of CMDM values ranging from 10^(-10) to 10^(-3).

关键词： beyond standard model flavor physics chromomagnetic dipole light quarks

exploring the effects of anthropogenic disturbance on predator inspection activity in Trinidadian guppies

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Current Zoology 2024年第1期70卷 109-111页

作者： Alix J.p brusseau Laurence e.A.Feyten Adam L.Crane Grant e.brown Department of biology Concordia UniversityMontrealQCH4B 1R6Canada Department of biomedical Sciences WCVMUniversity of SaskatchewanSaskatoonSKCanada

prey animals are often faced with uncertainty due to having imperfect information regarding current local conditions,including predation risks and the availability of reliable foraging opportunities(Dall 2010).As this uncertainty increases,the probability of making costly behavioral errors also increases,leading to more risk averse behavioral tactics(Feyten et al.2019).For example,Trinidadian guppies poecilia reticulata are far more risk averse when faced with multiple unknown sources of risk assessment information than when faced with a mix of known and unknown cues(Feyten et al.2019).prey can reduce uncertainty by gathering and integrating private and social information regarding current risk levels within microhabitats(Dall 2010;Munoz and blumstein 2012).

关键词： human disturbance information availability information reliability predator-prey interactions risk assessment uncertainty

exploring the electromagnetic shielding behavior of lanthanum doped calcium nanoferrites

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Journal of Rare earths 2024年第11期42卷 2128-2136页

作者： e.Ahilandeswari K.Sakthipandi R.Rajesh Kanna G.Rajkumar b.Ganesh babu S.Arunmetha Aslam Hossain p.Sakthivel V.Rajendran M.Srinidhi Raghavan Department of physics SRM TRP Engineering College Department of electronics and Communication engineering M. Kumarasamy College of Engineering Department of physics Easwari Engineering College Department of Mechanical engineering SRM TRP Engineering College Centre for Advanced energy Studies Department of Electronics and Communication EngineeringKoneru Lakshmaiah Education Foundation Smart Materials Research Institute Southern Federal University Centre for Materials Science Department of PhysicsScience and HumanitiesFaculty of EngineeringKarpagam Academy of Higher Education Centre for Nanotechnology Academy of Maritime Education and Training (Deemed to be University) Department of Chemistry and Centre for Nano-Materials and Displays B.M.S. College of Engineering

The present study focuses on the synthesis and characterization of lanthanum(La3+)-doped calcium nanoferrites(CaLaxFe2-xo4:x=0.025,0.050,0.075 and 0.100) using the sonochemical *** techniques were employed to analyze the effect of La3+infusion,Raman spectroscopy confirms the presence of active A1g,T2gand egmodes in the CaLaxFe2-xo4nanoferrite,indicating the formation of an active ferrite *** introduction of La3+doping results in a significant increase in the band gap energy,rendering the nanoferrites insulating（3.23-3,57 eV）.At higher frequencies,the impedance studies reveal minimal losses and better AC conductivity,pointing to improved dielectric *** higher frequencies,the Q-factor of La-doped calcium nanoferrites shows lower electromagnetic *** M-H curve exhibits ferromagnetic behavior,with La3+-doped calcium nano ferrites displaying a saturation magnetization ranging from 12.72 to 18.10 emu/*** incorporation of La3+also induces enhanced electrical polarization,leading to notable dielectric loss and increased absorption of electromagnetic ***,these CaLaxFe2-xo4nanoferrites demonstrate potential as effective microwave absorbers across a wide frequency range,with significant shielding absorption observed at 8.8-9.1 GHz.

关键词： Dielectric Magnetism Microwave absorption Nanoferrites Rare earths Structural properties

experimental measurements of gamma-photon production and estimation of electron/positron production on the peTAL laser facility

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Matter and Radiation at extremes 2024年第5期9卷 32-47页

作者： F.brun L.Ribotte G.boutoux X.Davoine p.e.Masson-Laborde Y.Sentoku N.Iwata N.blanchot D.batani I.Lantuéjoul L.Lecherbourg b.Rosse C.Rousseaux b.Vauzour D.Raffestin e.D’Humières X.Ribeyre Centre Lasers Intenses et Applications UMR 5107Universitéde Bordeaux-CNRS-CEA33405 TalenceFrance CeA DAMCESTAF-33116 Le BarpFrance CeA DAMDIFF-91297 ArpajonFrance CeA LMCEUniversitéParis-Saclay91680 Bruyères-le-ChâtelFrance Institute of Laser engineering Osaka University2-6 YamadaokaSuitaOsaka 565-0871Japan

This article reports the first measurements of high-energy photons produced with the high-intensity peTawatt Aquitaine Laser(peTAL)*** experiments were performed during the commissioning of the *** laser had an energy of about 400 J,an intensity of 8×10^(18)W cm^(−2),and a pulse duration of 660 fs(FWHM).It was shot at a 2 mm-thick solid tungsten *** high-energy photons were produced mainly from the bremsstrahlung process for relativistic electrons accelerated inside a plasma generated on the front side of the *** paper reports measurements of electrons,protons and *** electrons up to35 MeV with a few-MeV temperature were recorded by a spectrometer,called SeSAMe(SpectreÉlectronS Angulaire MoyenneÉnergie).K-and L-shells were clearly detected by a photon spectrometer called SpeCTIX(Spectromètre petalàCristal en TransmIssion pour le rayonnnement X).High-energy photons were diagnosed by CRACC-X(Cassette de RAdiographie Centre Chambre-rayonnement X),a bremsstrahlung *** cannon analysis is strongly dependent on the hypothesis adopted for the spectral *** shapes can exhibit similar reproductions of the experimental *** eliminate dependence on the shape hypothesis and to facilitate analysis of the data,simulations of the interaction were *** model the mechanisms involved,a simulation chain including hydrodynamic,particle-in-cell,and Monte Carlo simulations was *** simulations model the preplasma generated at the front of the target by the peTAL laser prepulse,the acceleration of electrons inside the plasma,the generation of MeV-range photons from these electrons,and the response of the detector impacted by the energetic photon *** this work enabled reproduction of the experimental *** high-energy photons produced have a large emission angle and an exponential distribution *** addition to the analysis of the photon spectra,positron production was also ***,if high

关键词： process positron hypothesis