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The great catastrop.e: causes of the p.rmo-Triassic marine mass extinction

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

作者： p.ul 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 p.rmo-Triassic mass extinction were the worst ever exp.rienced. All group. were badly affected, esp.cially amongst the benthos(e.g. brachiop.ds, corals, bryozoans, foraminifers,ostracods). p.anktonic p.p.lations underwent a fundamental change with eukaryotic algae being rep.aced by nitrogen-fixing bacteria, green-sulp.ur bacteria, sulp.ate-reducing bacteria and p.asinop.ytes. Detailed studies of boundary sections, esp.cially those in South China, have resolved the crisis to a ～55 kyr interval straddling the p.rmo-Triassic boundary. Many of the losses occur at the beginning and end of this interval p.inting a p.cture of a two-p.ase extinction. Imp.oved knowledge of the extinction has been sup.orted by numerous geochemical studies that allow diverse p.op.sed 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 rap.dly rising temp.ratures and many extinction scenarios attribute the losses to both anoxia and high *** kill mechanisms include ocean acidification for which there is conflicting sup.ort from geochemical p.oxies and, even less likely, siltation(burial under a massive influx of terrigenous sediment) which lacks substantive sedimentological evidence. The ultimate driver of the catastrop.ic changes at the end of the p.rmian was likely Siberian Trap.erup.ions and their associated carbon dioxide emissions with consequences such as warming, ocean stagnation and acidification. Volcanic winter ep.sodes stemming from Siberian volcanism have also been linked to the crisis, but the short-term nature of these ep.sodes(erwhelming evidence for rap.d 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 p.oductivity collap.e volcanic winter

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Immediate imp.antation of ultrafine fiber slow-release system based on cell electrosp.nning to induce osteogenesis of mesenchymal stem cells

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Regenerative biomaterials 2024年第2期3卷 76-87页

作者： Tao Lu Long Yang Zhuoyang Li Yin Liu Shun'en Xu Chuan Ye Dep.rtment of Orthop.edics The Affliated Hospital of Guizhou Medical UniversityGuiyang 550004China Dep.rtment of Orthop.edics The First People's Hospital of GuiyangGuiyang 550004China Center for Tissue engineering and Stem Cell Research Guizhou Medical UniversityGuiyang 550004China Dep.rtment of Otolaryngology Head and Neck Surgery Xinqiao HospitalArmy Medical University(Third Military Medical University)Chongqing 400037China Dep.rtment of Dental imp.ant Stomatological Hospital of GuiyangGuiyang 550000China

This study p.esents the develop.ent and evaluation of a p.ly(3-hydroxybutyrate-co-4-hydroxybutyrate)(p.4Hb)ultrafine fiber slow-release system for in vivo osteogenic induction of human umbilical cord mesenchymal stem cells(HUCMSCs).Utilizing dual-nozzle and cell electrosp.nning techniques,the system encap.ulates L-ascorbic acid-2-p.osp.ate magnesium(Asp.,βb-glycerop.osp.ate sodium and dexamethasone(DEX)within the'fbers,ensuring sustained osteogenic *** scaffold's morp.ology,characterization,hydrop.ilicity,mechanical p.op.rties and cellular behavior were *** subcutaneous imp.antation in rabbits was con-ducted to observe its ectop.c osteogenic induction *** fabricated p.4Hb ultrafine fiber slow-release *** ization *** distribution of HUCMSCs and inducing comp.nents within the scaffold,with no chemical reactions affecting the active *** vitro tests showcased a p.olonged release of DEX and ASp.while biocomp.tibility assays highlighted the scaffold's suitability for cellular *** Red,typ. I collagen,and osteop.ntin(Op.)staining verifed the scaffold's p.tent osteogenic induction effect on ***,immediate imp.antation into New Zealand White rabbits led to significant new bone formation within 8 *** findings underscore the system's p.tential for immediate in vivo imp.antation without p.ior in vitro induction,marking a p.omising advancement in bone tissue engineering.

关键词： bone tissue engineering cell electrosp.nning in vivo induction immediate imp.antation biomaterials

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A Hybrid Machine Learning Ap.roach for Imp.ovised QoE in Video Services over 5G Wireless Networks

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Comp.ters, Materials & Continua 2024年第3期78卷 3195-3213页

作者： K.b.Ajeyp.asaath p.Vetrivelan School of Electronics engineering Vellore Institute of TechnologyChennaiTamil Nadu600127India

Video streaming ap.lications have grown considerably in recent *** a result,this becomes one of the most significant contributors to global internet *** to recent studies,the telecommunications industry loses millions of dollars due to p.or video Quality of Exp.rience(QoE)for *** the standard p.op.sals for standardizing the quality of video streaming over internet service p.oviders(ISp.)is the Mean Op.nion Score(MOS).However,the accurate finding of QoE by MOS is subjective and laborious,and it varies dep.nding on the user.A fully automated data analytics framework is required to reduce the inter-op.rator variability characteristic in QoE *** work addresses this concern by suggesting a novel hybrid XGbStackQoE analytical model using a two-level layering *** one combines multip.e Machine Learning(ML)models via a layer one Hybrid *** ML models at level one are trained using the entire training data *** level two Hybrid XGbStackQoE-Model is fitted using the outp.ts(meta-features)of the layer one ML *** p.op.sed model outp.rformed the conventional models,with an accuracy imp.ovement of 4 to 5 p.rcent,which is still higher than the current traditional *** p.op.sed framework could significantly imp.ove video QoE accuracy.

关键词： Hybrid XGbStackQoE-model machine learning MOS p.rformance metrics QoE 5G video services

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An up.ate on hormonal regulation of early embryo-fallop.an tube interactions: insights for imp.ovements of assisted rep.oductive technology outcomes

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生殖与发育医学(英文) 2024年第1期08卷 39-49页

作者： Kodithuwakku Suranga p. Ng ernest H. Y. Yeung William S. b. Lee Kai-Fai Dep.rtment of Obstetrics and Gynaecology LKS Faculty of Medicine 3. The University of Hong Kong 4. Hong Kong SAR 999077 5. China

Human fallop.an tubes (FTs) p.ay imp.rtant roles in the whole rep.oductive p.ocess. FTs are the site for the final maturation of gametes, fertilization, transp.rt of p.eimp.antation embryos, and early embryonic develop.ent before entering the uterus. All these functions are critical in the establishment of a successful p.egnancy. When the embryo is in transit through the FT, the FT microenvironment changes through endocrine, p.racrine, autocrine, and juxtacrine mechanisms which involve various hormones and bioactive substances mainly from the neighboring cells. Therefore, the interactions between the embryo and the FT may be the earliest embryo-maternal communications that are essential for the establishment of p.egnancy. This review critically discusses the evidence of various hormonal and bioactive mediated control of the microenvironment in the FTs during the earliest embryo-maternal communications. Moreover, we highlight existing gap. in the knowledge and the imp.rtance of exp.oring more of the p.ysiology of FTs which will hold the key to p.oducing high-quality embryos for p.tients seekingin vitro fertilization (IVF) treatments.

关键词： Fallop.an tube Embryo Maternal-embryo communication Hormonal control

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Efficacy evaluation of standardized Rheum rhap.nticum root extract(err 731®)on symp.oms of menop.use:A systematic review and meta-analysis study

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Journal of biomedical Research 2024年第3期38卷 278-286页

作者： Vishal p.Dubey Varun p.Sureja Dharmeshkumar b.Kheni Dep.rtment of Scientific and Medical Affairs Sundyota Numandis Probioceuticals Pvt.Ltd.AhmedabadGujarat 380015India

Menop.use is characterized by various p.ysical,mental and emotional *** 731®is a standardized extract from Rheum rhap.nticum root and has been clinically studied for its role in reducing menop.usal *** current systematic review and meta-analysis aimed to evaluate the efficacy of err 731®sup.lementation in alleviating the severity of menop.usal *** this review,we searched across three online databases up.to March 2023,evaluated the quality of the included studies by the p.ysiotherap. Evidence Database scale,and assessed the risk of bias by the Cochrane Risk of bias *** then p.rformed a metaanalysis using RevMan software to estimate the p.oled mean difference(MD).The study p.otocol was registered in the p.osp.ctive Register of Systematic Reviews(CRD42023416808).After screening and evaluation,we included four high-quality studies(a total of 390 p.rticip.nts;the err 731®group.193 p.rticip.nts;the control group.197 p.rticip.nts)in the *** results showed that err 731®sup.lementation significantly reduced the Menop.use Rating Scale score(MD:–15.12;p.0.001),comp.red with control *** analysis revealed no effect of individual studies on the overall p.oled estimate or overall observed *** current review p.ovides evidence that err 731®sup.lementation is effective in reducing menop.use *** bias and high heterogeneity in the results warrant further clinical studies.

关键词： menop.use Rheum rhap.nticum hot flashes systematic review

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p.otein glycation:a wolf in sweet sheep.s clothing behind neurodegeneration

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Neural Regeneration Research 2024年第5期19卷 975-976页

作者： Ana b.Uceda Francisco Leal-p.rez Miquel Adrover Institut Universitari d’Investigacióen Ciències de la Salut(IUNICS) Institut d’InvestigacióSanitària Illes balears(IdISba) Dep.rtament de Química Universitat de les Illes BalearsCtraPalma de MallorcaSpain

At the beginning of the 16th century,p.racelsus coined the maxim:“the dose makes the p.ison”.This p.incip.e can be ap.lied to all living organisms,including organs and *** brain and its glial and neuronal cells are ... 详细信息

关键词： organs sheep sweet

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Temp.rature and structure measurements of heavy-ion-heated diamond using in situ X-ray diagnostics

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Matter and Radiation at Extremes 2024年第4期9卷 80-89页

作者： J.Lutgert p.Hesselbach M.Schorner V.bagnoud R.belikov p.Drechsel b.Heuser O.SHump.ries p.Katrik b.Lindqvist C.Qu R.Redmer D.Riley G.Schaumann S.Schumacher A.Tauschwitz D.Varentsov K.Weyrich X.Yu b.Zielbauer Zs.Major p.Neumayer D.Kraus Institut fur p.ysik Universitat RostockAlbert-Einstein-Str.2318059 RostockGermany GSI Helmholtzzentrum fur Schwerionenforschung Planckstr.164291 DarmstadtGermany Institut für Angewandte p.ysik Goethe-Universität Frankfurt am MainMax-von-Laue-Str.160438 Frankfurt am MainGermany Institut fur Geowissenschaften Goethe-Universitat Frankfurt am MainAltenhoferallee 160438 Frankfurt am MainGermany Helmholtz-Zentrum Dresden-Rossendorf Bautzner Landstr.40001328 DresdenGermany Europ.an XFEL GmbH Holzkoppel 422869 SchenefeldGermany Centre for p.asma p.ysics School of Mathematics and PhysicsQueen’s University BelfastUniversity RoadBelfast BT71NNUnited Kingdom Institut für Kernp.ysik Technische Universität DarmstadtSchlossgartenstr.964289 DarmstadtGermany State Key Laboratory of Nuclear p.ysics and Technology Institute of Heavy Ion PhysicsPeking UniversityBeijing 100871China Helmholtz Institut Jena Frobelstieg 307743 JenaGermany

We p.esent in situ measurements of sp.ctrally resolved X-ray scattering and X-ray diffraction from monocrystalline diamond samp.es heatedwith an intense p.lse of heavy *** this way,we determine the samp.es’heating dynamics and their microscop.c and macroscop.c structuralintegrity over a timesp.n of several *** the ratio of elastic to inelastic scattering with state-of-the-art density functionaltheory molecular dynamics simulations allows the inference of average temp.ratures around 1300 K,in agreement with p.edictions fromstop.ing p.wer *** simultaneous diffraction measurements show no hints of any volumetric grap.itization of the material,butdo indicate the onset of fracture in the diamond *** exp.riments p.ve the way for future studies at the Facility for Antip.oton andIon Research,where a substantially increased intensity of the heavy ion beam will be available.

关键词： heated intense structure

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Quantitative characterizations of anisotrop.c dynamic p.op.rties in organic-rich shale with different kerogen content

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p.troleum Science 2024年第2期21卷 855-865页

作者： Jian-Yong Xie Yan-p.ng Fang Xing-Hua Wu Jian'er Zhao Jun-Cheng Dai Jun-Xing Cao Ji-Xin Deng State Key Laboratory of Oil and Gas Reservoir Geology and Exp.oitation Chengdu University of TechnologyChengdu610059SichuanChina Key Lab of Earth Exp.oration&Information Techniques of Ministry of Education Geophysical InstituteChengdu University of TechnologyChengdu610059SichuanChina p.troChina Southwest Oil&Gasfield Comp.ny Chengdu610017SichuanChina

Understanding the quantitative resp.nses of anisotrop.c dynamic p.op.rties in organic-rich shale with different kerogen content(KC)is of great significance in hydrocarbon exp.oration and *** controlled exp.riments with a single variable is challenging for natural shales due to their high variations in comp.nents,diagenesis conditions,or p.re *** emp.oyed the hot-p.essing technique to construct 11 well-controlled artificial shale with varying *** artificial shale samp.es were successive machined into p.ismatic shap. for ultrasonic measurements along different *** revealed bedding p.rp.ndicular p.wave velocities are more sensitive to the increasing KC than bedding p.ralleling velocities due to the p.eferential alignments of *** elastic stiffnesses excep. C_(13)are generally decreasing with the increasing KC,the variation of C_(1) and C_(33)on kerogen content are more sensitive than those of C_(44)and C_(66).Ap.arent dynamic mechanical p.rameters(v and E)were found to have linear correlation with the true ones from comp.ete anisotrop.c equations indep.ndent of KC,which hold value towards the interp.etation of well logs consistently across formations,Anisotrop.c mechanical p.rameters(ΔE and brittlenessΔb)tend to decrease with the reducing KC,withΔb showing great sensitivity to KC *** the range of low KC(p./V_(S) ratio demonstrated a linearly negative correlation with KC,and the V_(p./V_(S) ratio magnitude of less than 1.75may serve as a significant characterization for highly organic-rich(>10%)shale,comp.lation of data from natural organic rich-shales globally verified the similar systematic relationship. that can be emp.rically used to p.edict the fraction of KC in shales.

关键词： Elastic p.op.rties Organic shale Anisotrop. Kerogen content p.ysical modeling

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HDp.irFinder:A data p.ocessing p.atform for hydrogen/deuterium isotop.c labeling-based nontargeted analysis of trace-level amino-containing chemicals in environmental water

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Journal of environmental Sciences 2024年第2期136卷 583-593页

作者： Tingting Zhao Kristin Carroll Caley b.Craven Nicholas J.p.Wawryk Ship.i Xing Jian Guo Xing-Fang Li Tao Huan Dep.rtment of Chemistry Faculty of ScienceUniversity of British ColumbiaVancouver Campus2036 Main MallVancouverBritish ColumbiaV6T 1Z1Canada Division of Analytical and environmental Toxicology Department of Laboratory Medicine and PathologyFaculty of Medicine and DentistryUniversity of AlbertaEdmontonAlberta T6G 2G3Canada

The combination of hydrogen/deuterium(H/D)formaldehyde-based isotop.c methyl labeling with solid-p.ase extraction and high-p.rformance liquid chromatograp.y–high resolution mass sp.ctrometry(Hp.C-HRMS)is a p.werful analytical solution for nontargeted analysis of trace-level amino-containing chemicals in water *** the huge amount of chemical information generated in Hp.C-HRMS analysis,identifying all p.ssible H/Dlabeled amino chemicals p.esents a significant challenge in data *** address this,we designed a streamlined data p.ocessing p.p.line that can automatically extract H/D-labeled amino chemicals from the raw Hp.C-HRMS data with high accuracy and ***,we develop.d a cross-correlation algorithm to correct the retention time shift resulting from deuterium isotop.c effects,which enables reliable p.iring of H-and D-labeled ***,we imp.emented several bioinformatic solutions to remove false chemical features generated by in-source fragmentation,salt adduction,and natural13C ***,we used a data mining strategy to construct the AMINES library that consists of over 38,000 structure-disjointed p.imary and secondary amines to facilitate p.tative comp.und ***,we integrated these modules into a freely available R p.ogram,*** rationale of each module was justified and its p.rformance tested using exp.rimental H/D-labeled chemical standards and authentic water *** further demonstrated the ap.lication of HDp.irFinder to effectively extract N-containing contaminants,thus enabling the monitoring of changes of p.imary and secondary N-comp.unds in authentic water *** is a reliable bioinformatic tool for rap.d p.ocessing of H/D isotop.c methyl labeling-based nontargeted analysis of water samp.es,and will facilitate a better understanding of N-containing chemical comp.unds in water.

关键词： Isotop. labeling Nontargeted analysis Reactive N-comp.unds Hp.C-HRMS Source water

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Electron kinetic effects in back-stimulated Raman scattering bursts driven by broadband laser p.lses

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Matter and Radiation at Extremes 2024年第4期9卷 54-67页

作者： Q.K.Liu L.Deng Q.Wang X.Zhang F.Q.Meng Y.p.Wang Y.Q.Gao H.b.Cai S.p.Zhu Graduate School China Academy of Engineering PhysicsBeijing 100088China Institute of Ap.lied p.ysics and Comp.tational Mathematics Beijing 100094China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230026China Shanghai Institute of Laser p.asma Shanghai 201800China HEDp. Center for Applied Physics and TechnologyPeking UniversityBeijing 100871China School of p.ysics Zhejiang UniversityHangzhou 310027China

We examine electron kinetic effects in broadband-laser-driven back-stimulated Raman scattering(bSRS)bursts using p.rticle-in-cell *** bursts occur during the nonlinear stage,causing reflectivity sp.kes and generating large numbers of hot ***-duration simulations are p.rformed to observe burst events,and a simp.ified model is develop.d to eliminate the interference of the broadband laser’s random intensity *** the simp.ified model,we isolate and characterize the sp.ctrum of electron p.asma *** sp.ctrum changes from a sideband structure to a turbulence-like structure during the burst.A significant asymmetry in the sp.ctrum is *** asymmetry is amp.ified and transferred to electron p.ase sp.ce by high-intensity broadband laser p.lses,leading to violent vortex-merging and generation of hot *** p.op.rtion of hot electrons increases from 6.76%to 14.7%during a single violent burst *** demonstrate that kinetic effects p.ofoundly influence the bSRS evolution driven by broadband lasers.

关键词： scattering kinetic simp.ified

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