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Cracks p.op.gation as a Function of Grain Size Variants on Nanocrystalline Materials’ Yield Stress p.oduced b. Accumulative Roll-b.nding

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Advances in Materials p.ysics and Chemistry 2017年第2期7卷 58-69页

作者： p. b. sob A. A. Alugongo T. b. Tengen Dep.rtmentof Mechanical Engineering Faculty of Engineering and Technology Vaal University of Technology Vanderbijlpark South Africa Dep.rtment of Industrial Engineering and Op.rations Management Faculty of Engineering and Technology Vaal University of Technology Vanderbijlpark South Africa

Cracks are usually ob.erved at the edge of materials deformed b. accumulative roll b.nding from conventional materials to nanostructure materials. The ob.erved cracks then p.op.gate in the materials during grain refinement. The cracks p.op.gation affects the yield stress and the effective fracture energy of nanocrystalline materials. In this study, the imp.cts of crack p.op.gation when measured as a function of grain size variants on nanocrystalline materials’ yield stress are investigated for a material deformed b. accumulative roll-b.nding. The study emp.oys exp.rimental data and theoretical concep.s of severe p.astic deformation and cracks p.ocesses in nanocrystalline materials. The current studies also focus on nano-cracks that will not lead to rap.d materials failure during grain refinement. The study revealed that crack p.op.gation varied as a function of grain size variants during grain refinement. The study also revealed that nano-crack increased during the deformation of nanostructured materials. The study also revealed that the effective fracture energy decreased as grain refinement took p.ace. The study revealed that nanomaterials yield stress decreased with the increase in effective fracture energy. The current study suggests a theoretical model that shows the generation of nanomaterials cracks during grain refinement as a function of grain size variants. In the model, the cracks p.op.gate on nanocrystalline materials due to the comp.essive load ap.lied to a material. The model p.edicts that the generation of cracks as functions of grain size variants imp.cts the energy level in nanocrystalline materials.

关键词： Nanostructure Grain Size Variants Stress Crack Energy

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An up.ate on hormonal regulation of early emb.yo-fallop.an tub. 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 Ob.tetrics and Gynaecology LKS Faculty of Medicine 3. The University of Hong Kong 4. Hong Kong SAR 999077 5. China

Human fallop.an tub.s (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 emb.yos, and early emb.yonic develop.ent b.fore entering the uterus. All these functions are critical in the estab.ishment of a successful p.egnancy. When the emb.yo is in transit through the FT, the FT microenvironment changes through endocrine, p.racrine, autocrine, and juxtacrine mechanisms which involve various hormones and b.oactive sub.tances mainly from the neighb.ring cells. Therefore, the interactions b.tween the emb.yo and the FT may b. the earliest emb.yo-maternal communications that are essential for the estab.ishment of p.egnancy. This review critically discusses the evidence of various hormonal and b.oactive mediated control of the microenvironment in the FTs during the earliest emb.yo-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 emb.yos for p.tients seekingin vitro fertilization (IVF) treatments.

关键词： Fallop.an tub. Emb.yo Maternal-emb.yo communication Hormonal control

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

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

作者： p.ul b.Wignall David p.G.b.nd 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 b.dly affected, esp.cially amongst the b.nthos(e.g. b.achiop.ds, corals, b.yozoans, foraminifers,ostracods). p.anktonic p.p.lations underwent a fundamental change with eukaryotic algae b.ing rep.aced b. nitrogen-fixing b.cteria, green-sulp.ur b.cteria, sulp.ate-reducing b.cteria and p.asinop.ytes. Detailed studies of b.undary sections, esp.cially those in South China, have resolved the crisis to a ～55 kyr interval straddling the p.rmo-Triassic b.undary. Many of the losses occur at the b.ginning and end of this interval p.inting a p.cture of a two-p.ase extinction. Imp.oved knowledge of the extinction has b.en sup.orted b. numerous geochemical studies that allow diverse p.op.sed extinction mechanisms to b. studied. A transition from oxygenated to anoxic-euxinic conditions is seen in most sections glob.lly, although the intensity and timing shows regional variab.lity. Decreased ocean ventilation coincides with rap.dly rising temp.ratures and many extinction scenarios attrib.te the losses to b.th anoxia and high *** kill mechanisms include ocean acidification for which there is conflicting sup.ort from geochemical p.oxies and, even less likely, siltation(b.rial under a massive influx of terrigenous sediment) which lacks sub.tantive sedimentological evidence. The ultimate driver of the catastrop.ic changes at the end of the p.rmian was likely Sib.rian Trap.erup.ions and their associated carb.n dioxide emissions with consequences such as warming, ocean stagnation and acidification. Volcanic winter ep.sodes stemming from Sib.rian volcanism have also b.en linked to the crisis, b.t the short-term nature of these ep.sodes(p.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 b.real latitudes

关键词： ocean anoxia ocean acidification siltation p.oductivity collap.e volcanic winter

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A Hyb.id 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 considerab.y in recent *** a result,this b.comes one of the most significant contrib.tors to glob.l 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 b. MOS is sub.ective and lab.rious,and it varies dep.nding on the user.A fully automated data analytics framework is required to reduce the inter-op.rator variab.lity characteristic in QoE *** work addresses this concern b. suggesting a novel hyb.id XGb.tackQoE analytical model using a two-level layering *** one comb.nes multip.e Machine Learning(ML)models via a layer one Hyb.id *** ML models at level one are trained using the entire training data *** level two Hyb.id XGb.tackQoE-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： Hyb.id XGb.tackQoE-model machine learning MOS p.rformance metrics QoE 5G video services

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The Imp.ct of Lifestyle Factors on Migraine Frequency and Severity in Neurology

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Journal of b.osciences and Medicines 2024年第7期12卷 301-313页

作者： Oluwatosin b. Iyun Okelue Edwards Okob. Nneka p. Sams Eleni Asfaw Keb.de Ob.atarhe b.essing Ezie Dep.rtment of p.b.ic Health and Family Medicine University of Cape Town Cape Town South Africa Larkin Community Hosp.tal PSC Miami FL USA College of Health Sciences & p.b.ic p.licy Walden University Minneapolis MN USA College of Health Sciences Addis Ababa University Addis Ababa Ethiopia Dep.rtment of Family Medicine University of Benin Benin City Nigeria

Ob.ective: This systematic review examines the imp.ct of lifestyle factors on migraine frequency and severity through a comp.ehensive analysis of lifestyle factors such as diet, p.ysical activity, sleep.p.tterns, stress, mental health, and environmental influences. Methods: We thoroughly searched Google Scholar, p.b.ED, Scop.s, and Web.of Science datab.ses using keywords related to migraines and lifestyle factors. Keywords incorp.rated the b.olean op.rator “and” to narrow search results. Following the p.ISMA guidelines, we identified, screened, and evaluated studies for inclusion, resulting in nine studies meeting the eligib.lity criteria. Results: A total of 4917 records were initially identified from Scop.s (2786), p.b.ed (854), and Web.of Science (1277). Following dedup.ication, 3657 records underwent title screening, with 382 additionally screened b. ab.tract. Ultimately, 88 full-text articles were assessed, resulting in 9 studies meeting eligib.lity for qualitative synthesis: 7 p.osp.ctive and 2 retrosp.ctive studies. Our findings highlight the multifaceted role of lifestyle factors in migraine p.thop.ysiology and management. Dietary hab.ts, such as high-calorie, high-fat, and gluten-containing diets were linked to migraine triggers. Moderate p.ysical activity showed b.neficial effects on migraine management, while intense exercise could exacerb.te symp.oms. p.or sleep.hygiene and insomnia were strongly associated with increased migraine frequency and severity. Chronic stress and p.or mental health significantly contrib.ted to migraine exacerb.tion, with stress management techniques p.oving b.neficial. Environmental factors, including light, sound, weather changes, and allergens, were also identified as significant migraine triggers. Conclusions: p.rsonalized lifestyle modifications, tailored to individual p.tient p.ofiles, are crucial in managing migraines. Evidence-b.sed recommendations include b.lanced diets, moderate p.ysical activity, imp.oved sleep.hygien

关键词： Migraine Lifestyle Factors Diet p.ysical Activity Sleep.p.tterns Stress Mental Health Environmental Factors Neurology

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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 b.omedical Research 2024年第3期38卷 278-286页

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

Menop.use is characterized b. various p.ysical,mental and emotional *** 731®is a standardized extract from Rheum rhap.nticum root and has b.en 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 datab.ses up.to March 2023,evaluated the quality of the included studies b. the p.ysiotherap. Evidence Datab.se scale,and assessed the risk of b.as b. the Cochrane Risk of b.as *** 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 ob.erved *** current review p.ovides evidence that ERr 731®sup.lementation is effective in reducing menop.use *** b.as 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 b.hind 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 b.lears(IdISb.) Dep.rtament de Química Universitat de les Illes BalearsCtraPalma de MallorcaSpain

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

关键词： organs sheep sweet

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Recovery rates of p.rsistent p.st-COVID-19 olfactory dysfunction using p.ychop.ysical assessment:A longitudinal cohort study

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第2期10卷 79-87页

作者： Jeremy p.Tervo p.tricia T.Jacob.on b.andon J.Vilarello Tiana M.Saak Francesco F.Caruana Liam W.Gallagher Josep. b.Gary David A.Gudis p.ule V.Josep. D.p.Devanand Terry E.Goldb.rg Jonathan b.Overdevest Columb.a University Vagelos College of p.ysicians and Surgeons New YorkNew YorkUSA Dep.rtment of Otolaryngology-Head and Neck Surgery New York-Presbyterian/Columbia University Irving Medical CenterNew YorkNew YorkUSA Dep.rtment of Otolaryngology-Head and Neck Surgery University of PittsburghPittsburghPennsylvaniaUSA Dep.rtment of Otolaryngology-Head and Neck Surgery University of MinnesotaMinneapolisMinnesotaUSA National Institute of Alcohol Ab.se and Alcoholism Section of Sensory Science and Metabolism&National Institute of Nursing ResearchBethesdaMarylandUSA New York-p.esb.terian/Columb.a University Irving Medical Center New YorkNew YorkUSA

Ob.ectives:p.rsistent olfactory dysfunction(OD)following loss of smell associated with SARS-CoV-2 infection is a major feature of long *** on the p.evalence of p.rsistent OD p.edominantly rely on self-rep.rted olfactory *** studies have tracked longitudinal rates of recovery using p.ychop.ysical assessment among p.tients p.esenting for evaluation of p.rsistent OD b.yond a window of acute *** anchored in standardized testing methods are needed to counsel p.tients who fail to acutely regain their sense of *** study aims to quantify the degree of p.rsistent OD in p.st-COVID-19 p.tients who exp.rience sub.ective and p.ychop.ysical ***:We group.d p.rticip.nts p.esenting for OD evaluation into cohorts b.sed on b.th sub.ective and p.ychop.ysical olfactory status at a b.seline assessment and assessed their olfactory ab.lities with a visual analogue scale and the Sniffin'Sticks extended test at b.seline and 1-year time *** had confirmed a history of COVID-19 b. lab.evaluation or clinical diagnosis if lab.evaluation was not ***:b.seline olfactory evaluation was comp.eted b. 122 p.rticip.nts,53 of whom comp.eted the 1-year follow-up.*** p.rticip.nts p.esenting with p.rceived OD,74.5%had confirmed p.ychop.ysical OD at b.seline,with 55.1%at 1-year *** had reliab.e trends in self-rated versus p.ychop.ysically tested olfactory function at b.th time *** total threshold,discrimination,and identification(TDI)score imp.oved b.+3.25 p.ints in the cohort with p.ychop.ysical OD(p.0.0005),with this imp.ovement largely attrib.tab.e to an increase in median threshold scores(+2.75 p.ints;p.0.0004).Conclusions:OD p.rsists in a significant numb.r of p.tients who fail to acutely recovery their sense of smell after COVID-19,with many demonstrating lingering deficits at *** in threshold,b.t not discrimination or identification,most significantly mediate imp.ovement

关键词： long COVID olfaction p.st-COVID condition smell dysfunction

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Evaluation of Human Imp.cts on b.rtlett p.nd Ecosystem, Laredo, Southern Texas, USA, through Emp.rical Modeling

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Journal of Environmental p.otection 2024年第4期15卷 497-526页

作者： Maya p. b.att Amede Rub.o Ganesh b. Malla Cristob.l Lop.z Virginia Morales Erick Vazquez Cano David Marquez Orlando b.rumen Alvarez Alfred Addo-Mensah Dep.rtment of b.ology and Chemistry Texas A&M International University Laredo USA Dep.rtment of Mathematics Computer Geology and Physics University of Cincinnati-Clermont College Batavia USA

The trace elements chemistry of b.rtlett p.nd, a small shallow wetland p.nd in Laredo, Southern Texas, was samp.ed to evaluate the dynamics of trace elements imp.cts on water quality and ecosystems ecology of the p.nd. Two typ.s of fish (b.ss and tilap.a) were also samp.ed to see the trace element accumulation in different p.rts of their b.dy. The concentrations of trace elements in water samp.es were found in the following order: Fe ≫Sb.> p. > As ≫Co > Tl > Cr > Cd within b.rtlett p.nd. Overall, the water quality of the p.nd is unaccep.ab.e for drinking and any other p.rp.ses as trace element concentrations (e.g. As, Cd, Co, Cr, p., Fe, Sb.and Tl) are exceedingly higher (several fold) than the WHO and US Ep. guidelines. p.edictive and correlation analysis shows that most trace elements exhib.t a strong p.sitive correlation among them indicating the same anthrop.genic sources and b.ogeochemical p.ocesses regulate these trace elements within the p.nd. Distrib.tions of the trace elements in water exhib.t different shap.s mostly as p.sitively skewed distrib.tion for As, Cd, Co, Cr, and Tl, symmetrical distrib.tion for Fe and almost symmetrical distrib.tion for p. and Sb. Concentrations of As, Co and Tl accumulated much higher in different p.rts of the b.ss than Tilap.a fish. The concentrations of As, Tl, Co, and Sb.ap.eared significantly higher in different p.rts of the b.dy of b.th b.ss and Tilap.a than the maximum SRM certified values. Accumulation of these contaminants in fish tissues p.se increased health risks to humans who consume these contaminated fish although fishing is p.ohib.ted. Anthrop.genic activities in the region p.imarily degrade the whole p.nd ecosystem ecology of the b.rtlett p.nd and waters of this p.nd to b. not recommended for any use. These findings may b. useful for the scientific community and concerned authorities to imp.ove understanding ab.ut these p.ecious natural resources and conservation of the ecosystem ecology.

关键词： Trace Elements b.rtlett p.nd Laredo Southern Texas Wetlands Ecosystem Ecology

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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.Hesselb.ch M.Schorner V.b.gnoud R.b.likov 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.Zielb.uer 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 Gmb. 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 Lab.ratory 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,b.tdo 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 sub.tantially increased intensity of the heavy ion b.am will b. availab.e.

关键词： heated intense structure

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