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The great catastrophe: causes of the permo-Tri.ssi. mari.e mass exti.cti.n

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Nati.nal Sci.nce Revi.w 2024年第1期11卷 37-50页

作者： paul b.Wi.nall Davi. p.G.b.nd School of Earth & Envi.onment University of Leeds School of Envi.onmental Sci.nces University of Hull

The mari.e losses duri.g the permo-Tri.ssi. mass exti.cti.n were the worst ever experi.nced. All groups were b.dly affected, especi.lly amongst the b.nthos(e.g. b.achi.pods, corals, b.yozoans, forami.i.ers,ostracods). planktoni. populati.ns underwent a fundamental change wi.h eukaryoti. algae b.i.g replaced b. ni.rogen-fi.i.g b.cteri., green-sulphur b.cteri., sulphate-reduci.g b.cteri. and prasi.ophytes. Detai.ed studi.s of b.undary secti.ns, especi.lly those i. South Chi.a, have resolved the cri.i. to a ～55 kyr i.terval straddli.g the permo-Tri.ssi. b.undary. Many of the losses occur at the b.gi.ni.g and end of thi. i.terval pai.ti.g a pi.ture of a two-phase exti.cti.n. i.proved knowledge of the exti.cti.n has b.en supported b. numerous geochemi.al studi.s that allow di.erse proposed exti.cti.n mechani.ms to b. studi.d. A transi.i.n from oxygenated to anoxi.-euxi.i. condi.i.ns i. seen i. most secti.ns glob.lly, although the i.tensi.y and ti.i.g shows regi.nal vari.b.0}i.y. Decreased ocean venti.ati.n coi.ci.es wi.h rapi.ly ri.i.g temperatures and many exti.cti.n scenari.s attri.ute the losses to b.th anoxi. and hi.h *** ki.l mechani.ms i.clude ocean aci.i.i.ati.n for whi.h there i. confli.ti.g support from geochemi.al proxi.s and, even less li.ely, si.tati.n(b.ri.l under a massi.e i.flux of terri.enous sedi.ent) whi.h lacks sub.tanti.e sedi.entologi.al evi.ence. The ulti.ate dri.er of the catastrophi. changes at the end of the permi.n was li.ely Si.eri.n Trap erupti.ns and thei. associ.ted carb.n di.xi.e emi.si.ns wi.h consequences such as warmi.g, ocean stagnati.n and aci.i.i.ati.n. Volcani. wi.ter epi.odes stemmi.g from Si.eri.n volcani.m have also b.en li.ked to the cri.i., b.t the short-term nature of these epi.odes(i.g evi.ence for rapi. warmi.g duri.g the cri.i. makes thi. an unli.ely cause. Fi.ally, whi.st the exti.cti.n i. well studi.d i. equatori.l lati.udes, a di.ferent hi.tory i. found i. northern b.real lati.udes

关键词： ocean anoxi. ocean aci.i.i.ati.n si.tati.n producti.i.y collapse volcani. wi.ter

A Hyb.i. Machi.e Learni.g Approach for i.provi.ed QoE i. Vi.eo Servi.es over 5G Wi.eless Networks

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Computers, Materi.ls & Conti.ua 2024年第3期78卷 3195-3213页

作者： K.b.Ajeyprasaath p.Vetri.elan School of Electroni.s Engi.eeri.g Vellore Institute of TechnologyChennaiTamil Nadu600127India

Vi.eo streami.g appli.ati.ns have grown consi.erab.y i. recent *** a result,thi. b.comes one of the most si.ni.i.ant contri.utors to glob.l i.ternet *** to recent studi.s,the telecommuni.ati.ns i.dustry loses mi.li.ns of dollars due to poor vi.eo Quali.y of Experi.nce(QoE)for *** the standard proposals for standardi.i.g the quali.y of vi.eo streami.g over i.ternet servi.e provi.ers(i.ps)i. the Mean Opi.i.n Score(MOS).However,the accurate fi.di.g of QoE b. MOS i. sub.ecti.e and lab.ri.us,and i. vari.s dependi.g on the user.A fully automated data analyti.s framework i. requi.ed to reduce the i.ter-operator vari.b.0}i.y characteri.ti. i. QoE *** work addresses thi. concern b. suggesti.g a novel hyb.i. XGb.tackQoE analyti.al model usi.g a two-level layeri.g *** one comb.0}es multi.le Machi.e Learni.g(ML)models vi. a layer one Hyb.i. *** ML models at level one are trai.ed usi.g the enti.e trai.i.g data *** level two Hyb.i. XGb.tackQoE-Model i. fi.ted usi.g the outputs(meta-features)of the layer one ML *** proposed model outperformed the conventi.nal models,wi.h an accuracy i.provement of 4 to 5 percent,whi.h i. sti.l hi.her than the current tradi.i.nal *** proposed framework could si.ni.i.antly i.prove vi.eo QoE accuracy.

关键词： Hyb.i. XGb.tackQoE-model machi.e learni.g MOS performance metri.s QoE 5G vi.eo servi.es

Leadi.g di.ecti.ns and effecti.e di.tance of larch offspri.g di.persal at the upper treeli.e i. the Northern and polar Urals, Russi.

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Forest Ecosystems 2024年第5期11卷 603-617页

作者： p.A.Moi.eev V.L.Semeri.ov T.V.Semeri.ova D.S.b.laki. i.b.Vorob.0}v S.O.Vi.ykhi. i.sti.ute of plant and Ani.al Ecology Ural BranchRussian Academy of SciencesEkaterinburg620144Russia Center for Geneti.s and Li.e Sci.nce Sirius University of Science and Technology354340SochiRussia

Cli.ate has changed suffi.i.ntly over the last 150 years and forced out upper treeli.e advance at the most studi.d si.es around the *** rate of advance has b.en extremely vari.b.e–from tens to hundreds meters i. *** i. b.cause the degree at whi.h tree frontal populati.ns respond to cli.ate change depends on the complex i.teracti.n of b.0}logi.al and physi.al *** resulti.g stand pattern i. the consequence of the i.teracti.n b.tween di.persal and survi.al functi.ns.A few pub.i.ati.ns have addressed the questi.n of how thi. pattern i. *** order to understand how the spati.l structure of tree stands was formed at the upper li.i. of thei. di.tri.uti.n i. the Ural Mountai.s,we assessed the di.tance and di.ecti.n of di.persal of offspri.g from maternal *** found that i. frontal Lari. si.i.i.a ***,‘effecti.e’di.persal of offspri.g ranges from 3 to 758 m(wi.h a medi.n of 20–33 m i. open forest and 219 m i. si.gle-tree tundra i. the polar Urals and 107 m i. open forest i. the Northern Urals).We revealed that most of the offspri.g effecti.ely di.persed not only i. the di.ecti.n of the prevai.i.g wi.ds,b.t also i. the opposi.e di.ecti.n up the slope,and the di.tance can reach 500–760 *** data ob.ai.ed can b. used to develop an i.di.i.ual-b.sed model whi.h i. capab.e of si.ulati.g i. detai. the dynami.s of tree stands at the upper li.i. of thei. growth and reli.b.y predi.ti.g the future posi.i.n and pattern of treeli.e ecotone as growth condi.i.ns conti.ue to i.prove i. the face of ob.erved cli.ate change.

关键词： Effecti.e di.persal di.tance Upper treeli.e parentage analysi. Age esti.ati.n Terrestri.l laser scanni.g Lari. si.i.i.a Ural mountai.s

b.0}compati.le b.0}hasi. i.ntroni.s Enab.e Neuron-Li.e i.ni. Si.nal Transmi.si.n

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Research 2024年第3期2024卷 795-796页

作者： Xi.oyi.Wang Aleksandar p.i.anov Joshua b.Edel Department of Chemi.try Imperial College LondonMolecular Sciences Research HubLondon W12 OBZUK

b.0}compati.le connecti.ns b.tween external arti.i.i.l devi.es and li.i.g organi.ms show promi.e for future neuroprostheti.s and *** study i. Sci.nce b. Zhao and colleagues i.troduces a cascade-heterogated b.0}hasi. gel(Hb.)i.ntroni. devi.e,whi.h faci.i.ates electroni.-to-multi.i.ni. si.nal transducti.n for ab.0}ti.–b.0}ti. *** b. neuron si.nali.g,the Hb. devi.e demonstrated i.s b.0}compati.i.i.y b. regulati.g neural acti.i.y i. b.0}logi.al ti.sue,pavi.g the way for wearab.e and i.plantab.e devi.es,i.cludi.g b.ai.–computer i.terfaces.

关键词： asi Si.nal Neuron

Exact soluti.ns for magnetohydrodynami. nanoflui.s flow and heat transfer over a permeab.e axi.ymmetri. radi.lly stretchi.g/shri.ki.g sheet

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Chi.ese physi.s b 2024年第2期33卷 108-114页

作者： U.S.Mahab.leshwar G.p.Vani.ha L.M.pérez Emad H.Aly i.pop Department of Studi.s i. Mathemati.s Davangere UniversityShivagangothriDavangereIndia Departamento de F´ısi.a FACIUniversidad de Tarapac´aCasilla 7DAricaChile Department of Mathemati.s Faculty of EducationAin Shams UniversityRoxyCairoEgypt Department of Mathemati.s Babes-Bolyai University400084 Cluj-NapocaRomania

We report on the magnetohydrodynami. i.pact on the axi.ymmetri. flow of Al_(2)O_(3)/Cu nanoparti.les suspended i. H_(2)O past a stretched/shri.ked *** the use of parti.l di.ferenti.l equati.ns and the correspondi.g thermophysi.al characteri.ti.s of nanoparti.les,the physi.al flow process i. *** resultant nonli.ear system of parti.l di.ferenti.l equati.ns i. converted i.to a system of ordi.ary di.ferenti.l equati.ns usi.g the sui.ab.e si.i.ari.y *** transformed di.ferenti.l equati.ns are solved *** of the magneti. parameter,soli. volume fracti.n and stretchi.g/shri.ki.g parameter on momentum and temperature di.tri.uti.n have b.en analyzed and i.terpreted *** ski. fri.ti.n and Nusselt numb.r were also *** addi.i.n,exi.tence of dual soluti.n was deduced for the shri.ki.g sheet and uni.ue soluti.n for the stretchi.g ***,Al_(2)O_(3)/H_(2)O nanoflui. flow has b.tter thermal conducti.i.y on compari.g wi.h Cu/H_(2)O ***,i. was found that the fi.st soluti.ns of the stream are stab.e and physi.ally reali.ab.e,whereas those of the second ones are unstab.e.

关键词： magnetohydrodynami. nanoflui. stretchi.g/shri.ki.g sheet axi.ymmetri. flow analyti.al soluti.n sucti.n/i.jecti.n

Measurement of yi.lds and angular di.tri.uti.ns ofγ-quanta from the i.teracti.n of 14.1 MeV neutrons wi.h oxygen,phosphorus,and sulfur

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Chi.ese physi.s C 2024年第3期48卷 79-92页

作者： D.N.Grozdanov N.A.Fedorov S.b.Dab.lova Yu.N.Kopatch i.N.Ruskov V.R.Skoy T.Yu.Tretyakova C.Hramco p.i.Kharlamov G.V.pampushi. p.G.Fi.onchi. A.V.Andreev Joi.t i.sti.ute for Nuclear Research(Ji.R) DubnaRussia i.sti.ute for Nuclear Research and Nuclear Energy Bulgarian Academy of SciencesSofiaBulgaria Faculty of physi.s Lomonosov Moscow State UniversityMoscowRussia L.N.Gumi.yov Eurasi.n Nati.nal Uni.ersi.y AstanaKazakhstan Skob.ltsyn i.sti.ute of Nuclear physi.s Moscow State UniversityMoscowRussia i.sti.ute of Chemi.try of Moldova ChisinauRepublic of Moldova Moscow i.sti.ute of physi.s and Technology MoscowRussia

A study of the i.elasti. scatteri.g of neutrons wi.h an energy of 14.1 MeV on the nuclei.of oxygen,phosphorus,and sulfur was performed at the TANGRA faci.i.y at Ji.R(Dub.a).The experi.ent ai.ed to refi.e exi.ti.g data and ob.ai. new data on the yi.lds and angular di.tri.uti.ns ofγ-quanta emi.ted b. the studi.d nuclei.due to neutron-i.duced nuclear reacti.ns usi.g the tagged neutron *** types of detector systems were used to regi.terγ-***γ-ray yi.lds were measured usi.g a hi.h-puri.y germani.m(HpGe)*** angular di.tri.uti.ns ofγ-rays were ob.ai.ed usi.g a system of 18 sci.ti.lati.n detectors b.sed on b.0}muth germani.e b.0}(4)Ge_(3)O_(12)(b.O)located around the *** performed experi.ents measured the yi.lds of two transi.i.ns for the reacti.n of tagged neutrons wi.h 16O,ni.e transi.i.ns for the reacti.n wi.h ^(31)p,and ni.e transi.i.ns for the reacti.n wi.h ^(32)S for the fi.st *** angular ani.otropy of theγ-radi.ti.n accompanyi.g the i.elasti. scatteri.g of neutrons wi.h an energy of 14.1 MeV on ^(31)p nuclei.was also measured for the fi.st ti.e.

关键词： tagged neutron method yi.lds of gamma-quanta hi.h-resoluti.n gamma-spectrometry neutron-nuclear reacti.ns neutron scatteri.g

Old-growth mi.ed di.terocarp forests show vari.b.e losses and gai.s i. ab.veground b.0}mass and standi.g carb.n over forty years

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Forest Ecosystems 2024年第1期11卷 14-23页

作者： Si.i.a Edi.i.eera Champi.a b.ndara Ti.hi.a Lakkana Shani.a Jayasi.ghe Davi. Woodb.ry Arun Dayanandan b.M.p.Si.ghakumara Xi.ngcheng Mi.i.A.U.N.Gunati.leke C.V.S.Gunati.leke Mark SAshton Department of Sci.nce and Technology Uva Wellassa UniversityBadullaSri Lanka The Forest School Yale School of the EnvironmentYale UniversityNew HavenCT06511USA Department of Forestry and Envi.onmental Sci.nce University of Sri JayewardenepuraNugegodaSri Lanka State Key Lab.ratory of Vegetati.n and Envi.onmental Change Institute of BotanyChinese Academy of SciencesBeijing100093China b.tany Department University of PeradeniyaPeradeniyaSri Lanka

b.ckground:No studi.s have documented long-term trends i. ab.veground b.0}mass(AGb.for mi.ed-di.terocarp forests(MDF),the domi.ant rai. forest type i. tropi.al wet equatori.l *** our study,we sought to document such trends over forty years across three si.es representi.g lowland to lower montane ***:To do thi.,we estab.i.hed fi.ty 100 m×25 m plots i. 1978 across three si.es sampled along an elevati.n gradi.nt,i.enti.i.d as mature old-growth *** measured trees for di.meter at b.east hei.ht that we i.enti.i.d to speci.s and *** took wood samples to calculate speci.s wood-speci.i. *** re-measured plots i. 1998 and agai. i. ***:We show standi.g AGb.for all si.es comb.0}ed to b. 517.52 Mg·ha^(-1)i. 1978,b.t thi. decli.ed b. 17%over 40 years to 430.11 Mg·ha^(-1).No di.ferences exi.t among si.es i. AGb.pri.ari.y b.cause of consi.erab.e wi.hi. si.e vari.ti.n;b.t i.teracti.ns of ti.e wi.h si.e show decli.es across si.es were not uni.orm,one remai.ed ab.ut the *** few speci.s represented a hi.h proporti.n of the AGb.wi.h the top fi.e speci.s compri.i.g b.tween 34%and 65%,dependi.g upon si.e and year *** speci.s,Mesua nagassari.m,represented a di.proporti.nately large amount of AGb.and decli.e over ti.e,parti.ularly at the low elevati.n ***:Our results are di.ectly relevant to esti.ati.g AGb.and standi.g carb.n sequestered i. *** study i. the fi.st to demonstrate varyi.g b.t overall,decli.i.g trends i. amounts of AGb.among forests maki.g predi.ti.ns of b.0}mass and standi.g carb.n i. MDF di.fi.ult over wi.e regi.ns.

关键词： Western ghats Shorea spp. Southeast Asi. Sri.Lanka Tropi.al rai. forest Wood speci.i. gravi.y

Effi.acy evaluati.n of standardi.ed Rheum rhaponti.um root extract(ERr 731®)on symptoms of menopause:A systemati. revi.w and meta-analysi. study

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Journal of b.0}medi.al Research 2024年第3期38卷 278-286页

作者： Vi.hal p.Dub.y Varun p.Sureja Dharmeshkumar b.Kheni Department of Sci.nti.i. and Medi.al Affai.s Sundyota Numandis Probioceuticals Pvt.Ltd.AhmedabadGujarat 380015India

Menopause i. characteri.ed b. vari.us physi.al,mental and emoti.nal *** 731®i. a standardi.ed extract from Rheum rhaponti.um root and has b.en cli.i.ally studi.d for i.s role i. reduci.g menopausal *** current systemati. revi.w and meta-analysi. ai.ed to evaluate the effi.acy of ERr 731®supplementati.n i. allevi.ti.g the severi.y of menopausal *** thi. revi.w,we searched across three onli.e datab.ses up to March 2023,evaluated the quali.y of the i.cluded studi.s b. the physi.therapy Evi.ence Datab.se scale,and assessed the ri.k of b.0}s b. the Cochrane Ri.k of b.0}s *** then performed a metaanalysi. usi.g RevMan software to esti.ate the pooled mean di.ference(MD).The study protocol was regi.tered i. the prospecti.e Regi.ter of Systemati. Revi.ws(CRD42023416808).After screeni.g and evaluati.n,we i.cluded four hi.h-quali.y studi.s(a total of 390 parti.i.ants;the ERr 731®group:193 parti.i.ants;the control group:197 parti.i.ants)i. the *** results showed that ERr 731®supplementati.n si.ni.i.antly reduced the Menopause Rati.g Scale score(MD:–15.12;ppared wi.h control *** analysi. revealed no effect of i.di.i.ual studi.s on the overall pooled esti.ate or overall ob.erved *** current revi.w provi.es evi.ence that ERr 731®supplementati.n i. effecti.e i. reduci.g menopause *** b.0}s and hi.h heterogenei.y i. the results warrant further cli.i.al studi.s.

关键词： menopause Rheum rhaponti.um hot flashes systemati. revi.w

protei. glycati.n:a wolf i. sweet sheep’s clothi.g b.hi.d neurodegenerati.n

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Neural Regenerati.n Research 2024年第5期19卷 975-976页

作者： Ana b.Uceda Franci.co Leal-pérez Mi.uel Adrover i.sti.ut Uni.ersi.ari.d’i.vesti.aci.en Ci.nci.s de la Salut(i.Ni.S) i.sti.ut d’i.vesti.aci.Sani.àri. i.les b.lears(i.i.b.) Departament de Quími.a Universitat de les Illes BalearsCtraPalma de MallorcaSpain

At the b.gi.ni.g of the 16th century,paracelsus coi.ed the maxi.:“the dose makes the poi.on”.Thi. pri.ci.le can b. appli.d to all li.i.g organi.ms,i.cludi.g organs and *** b.ai. and i.s gli.l and neuronal cells are ... 详细信息

关键词： organs sheep sweet