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The g.eat catastrophe: causes of the Permo-Triassic marine mass extinction

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

作者： paul B.Wig.all 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 g.oups were badly affected, especially among.t the benthos(e.g. brachiopods, corals, bryozoans, foraminifers,ostracods). Planktonic populations underwent a fundamental chang. with eukaryotic alg.e being.replaced by nitrog.n-fixing.bacteria, g.een-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 beg.nning.and end of this interval painting.a picture of a two-phase extinction. Improved knowledg. of the extinction has been supported by numerous g.ochemical studies that allow diverse proposed extinction mechanisms to be studied. A transition from oxyg.nated to anoxic-euxinic conditions is seen in most sections g.obally, althoug. the intensity and timing.shows reg.onal variability. Decreased ocean ventilation coincides with rapidly rising.temperatures and many extinction scenarios attribute the losses to both anoxia and hig. *** kill mechanisms include ocean acidification for which there is conflicting.support from g.ochemical proxies and, even less likely, siltation(burial under a massive influx of terrig.nous sediment) which lacks substantive sedimentolog.cal evidence. The ultimate driver of the catastrophic chang.s at the end of the Permian was likely Siberian Trap eruptions and their associated carbon dioxide emissions with consequences such as warming. ocean stag.ation and acidification. Volcanic winter episodes stemming.from Siberian volcanism have also been linked to the crisis, but the short-term nature of these episodes(g.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

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Pressurized environments directly influence friction and wear of dry steel contacts—Investig.tions in a novel hig. fluid pressure tribometer

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Friction 2024年第7期12卷 1599-1617页

作者： paul REICHLE Jakob BARZ g.org.UMLAUF g.nter E.M.TOVAR Institute of Interfacial Process Eng.neering.and Plasma Technolog.(Ig.P) University of StuttgartStuttgart 70569Germany Fraunhofer Institute for Interfacial Eng.neering.and Biotechnolog.(Ig.) Stuttgart 70569Germany

To reduce the usag. of classical lubricants in deep drawing.a new tribolog.cal system based on volatile lubricants was ***,a volatile medium is injected under hig. pressure into the interstice between drawing.tool and sheet *** on temperature and pressure,the temporary lubricant may exist in its g.seous or liquid *** this study,a novel hig. fluid pressure tribometer was desig.ed to investig.te the friction and wear of dry steel contacts under comparable conditions like in dry deep ***,a new ball-on-disc tribometer was desig.ed and integ.ated into a hig.-pressure *** specifically investig.te the effects of different environments(technical air,liquid and g.seous carbon dioxide,nitrog.n,arg.n)at atmospheric and hig. pressure(0.1 MPa,6 MPa)on tribolog.,the specimens and all components were operating.*** the experiments,the friction was measured *** show that the hig.est friction occurs in air and the lowest in carbon dioxide *** to the experiments,the wear of the specimens was assessed along.with chang.s in surface chemistry related to tribochemical ***,the tribolog. of the dry sliding.contacts is correlated to chang.s of the surface *** differences as well as similarities reg.rding.the different fluid environments are *** the results show,the differences between the media used are most pronounced at elevated ***,this work g.ves clear indications on the suitability of volatile lubricants in dry friction or rather g.s lubrication,especially for dry deep drawing.

关键词： dry friction and dry wear g.s lubrication carbon dioxide tribo-layer dry metal forming

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Sing.e doses of p38 MAP kinase inhibitors or prednisolone affect CRP and IL-6 in patients with active Rheumatoid Arthritis (RA)

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Open Journal of Immunolog. 2012年第3期2卷 85-97页

作者： pauline T. Lukey Hayley C. Perry Shuying.Yang.Simon Parry Marion C. Dickson Virg.nia H. Norris paul g. russell Marie Watissée Inmaculada Rioja Keith P. Ray Scott Crowe Michael Binks g.axoSmithKline R&D Medicines Research Centre Stevenage UK

Purpose: To investig.te the effects of sing.e doses of losmapimod, dilmapimod (inhibitors of p38 MAPK) and prednisolone on biomarkers of systemic inflammation (serum C-reactive protein (CRP) and interleukin (IL)-6) in subjects with active rheumatoid arthritis (RA). Methods: Two randomized, double blind, placebo controlled, parallel g.oup, sing.e dose studies investig.ted the CRP and IL-6 dose-response relationships for losmapimod (study A) and dilmapimod and prednisolone (study B) in patients with active RA on stable weekly doses of methotrexate. CRP, IL-6 and other exploratory biomarkers were measured in blood at baseline and up to 72 hours post-dosing. Results: In study A, 51 subjects were randomized to receive losmapimod (7.5, 20 and 60 mg. or placebo and in study B, 77 subjects were randomized to receive dilmapimod (7.5, 15 and 25 mg. or prednisolone (10, 20 and 50 mg. or placebo. Sing.e doses of prednisolone caused a decrease in circulating.IL-6 detectable at 3 and 24 hours post-dose as well as a CRP sing.e-dose relationship at 48 hours post-dose in patients with active RA. All doses of losmapimod produced a statistically sig.ificant reduction in serum IL-6, 3 hours post-dose but had no effect on CRP. Dilmapimod had no effect on IL-6 or CRP at any dose or time. Conclusion: This sing.e-dose response clinical study desig. could be useful in the early clinical development of anti-inflammatory ag.nts for the treatment of rheumatoid arthritis. Inhibition of both circulating.IL-6 and CRP would increase confidence that a new chemical entity may have the potential to deliver clinical benefit in RA. Trial reg.stration: [***: NCT00256919 and NCT00134693].

关键词： p38 MAPK Prednisolone RA Biomarkers Proof of Mechanism Randomised Controlled Trial

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Towards a sustainable g.oliner construction in landflls by potential blending.of fly ash with kaolin clay alternative:a review with an insig.t to Indian scenario

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Waste Disposal and Sustainable Energ. 2024年第2期6卷 243-258页

作者： Kshitij Kumar Biswajit paul Department of Environmental Science and Eng.neering Indian Institute of Technology(Indian School of Mines)Dhanbad 826004JharkhandIndia

Electricity g.nerated throug. coal-based Thermal Power Plants(TPPs)has played a pivotal role in shaping.modern civiliza-tion,revolutionizing.industries,and improving.the quality of life for billions of people *** TPPs contribute to about 37%-40%of the g.obal energ. *** production,in turn,has a direct impact on the economy of any *** from this boon to humankind,these TPPs combusting.coal as their primary fuel also have specific environmen-tal impacts,the major ones being.water,air,and soil pollution due to unscientific disposal of hig.-quantity fly ash produced *** we can put this ash to g.od use,it may assist us in mitig.ting.the pollution caused by *** there are many conventional uses of fly ash,such as a pozzolanic material in the cement industry,more pathways need to be discovered to balance the hig. g.neration quantities with ***,a detailed description of its use in potential g.oliner applications is presented in this article.A g.oliner or a landfill liner acts as a virtually impenetrable layer to mitig.te the leachate penetration into the underneath subsoil and g.oundwater,thus preventing.*** are presently some studies that support the use of only fly ash in such ***,the properties of the g.oliners using.it are not so g.od to sig.ificantly mitig.te environmental deg.adation owing.to its hig. permeability and low densification *** bentonite conventionally used has limited deposits and is mined intensively for its use as a natural *** depos-its must also be conserved,and an alternative material that may serve similar application benefits,like bentonite,must be *** desired aim can be fulfilled if we blend this combustion residue with other suitable materials(such as kaolinite clay)with low ***,the article focuses on the possibilities of blending.fly ash with different clays for g.oliner construction to improve the in

关键词： Fly ash-g.oliner Environmental manag.ment Composite liner systems Bentonite Kaolin clay

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Strain-dependent alpha-synuclein spreading.in Parkinson's disease and multiple system atrophy

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Neural Reg.neration Research 2024年第12期19卷 2581-2582页

作者： Shuyu Zhang.paul Ling.r Department of Neurolog. School of MedicineUniversity Hospital rechts der IsarTechnical University of MunichMunichGermany Department of Neurolog. University Medical Center GöttingenGöttingenGermany Center for Biostructural Imag.ng.of Neurodeg.neration University Medical Center GöttingenGöttingenGermany

Parkinson's disease(PD) and atypical Parkinsonian syndromes,such as multiple system atrophy(MSA) and Dementia with Lewy bodies,are neurodeg.nerative movement disorders characterized by the accumulation of alphasynuclein(a-syn) *** a-syn ag.reg.tes propag.te throug.out the brain in a prion-like manner,where patholog.cal a-syn recruits endog.nous a-syn to form insoluble *** forms representing.intermediates on the way to insoluble ag.reg.tes result in the most pronounced neurotoxic effects.

关键词： atrophy endog.nous atypical

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Tensor perturbations from bounce inflation scenario in f(Q)g.avity

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 78-92页

作者： Kun Hu Tanmoy paul Taotao Qiu Institute of Astrophysics Central China Normal UniversityWuhan 430079China School of Physics Huazhong University of Science and TechnologyWuhan 430074China National Institute of Technolog. Jamshedpur Department of PhysicsJamshedpur 831014India

In this paper,we construct a bounce inflation cosmolog.cal scenario in the framework of the modified symmetric teleparallel g.avity,namely f(Q)theory,and investig.te the tensor perturbations *** is well-known,the tensor perturbations g.nerated in the very early Universe(inflation and pre-inflation reg.ons)can account for the primordial g.avitational waves(Pg.s)that are to be detected by the next g.neration of g. *** discuss the stability condition of the tensor perturbations in the bounce inflation process and investig.te in detail the evolution of the perturbation *** g.neral form of the tensor power spectrum is obtained both for larg. as well as small scale *** a result,we show both kinds of modes(short or long.waveleng.h modes),and the tensor spectrum may g.t a positive tilt in the parametric rang. where the tensor perturbation proves to be stable—this interesting.y hints an enhancement of g.avitational waves’amplitude in the backg.ound of the f(Q)bounce-inflation ***,we study the LQC-like scenario as a specific case of our model,in which,the primordial tensor power spectrum turns out to be nearly scale-invariant on both small and larg. scales.

关键词： bounce cosmolog. modified g.avity cosmolog.cal perturbations

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Smoking.of Carica papaya in Nig.ria:The rationale,the public health effects and policies for intervention

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Asian Pacific Journal of Tropical Medicine 2024年第3期17卷 95-96页

作者： Abolaji paul Adekeye Mental Health Department Federal Teaching HospitalIdo-EkitiEkiti StateNigeria Mental Health Department Afe Babalola UniversityAdo-EkitiEkiti StateNigeria

Psychoactive substance use is characterized by the habitual use of substances that have sig.ificant effects in altering.the activities of neurotransmitters in certain reg.ons of the ***,these alterations manifest as c... 详细信息

关键词： rational behaviour emotional

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Surface eng.neering.with ionic polymers on membranes for boron removal

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Frontiers of Chemical Science and Eng.neering 2024年第5期18卷 61-69页

作者： Xiting.Zhang.Chenyi Fang.J paul Chen Sui Zhang Department of Chemical and Biomolecular Eng.neering National University of SingaporeSingapore 117576Singapore Department of Civil and Environmental Eng.neering National University of SingaporeSingapore 119260Singapore Colleg. of Chemistry and Environmental Eng.neering Shenzhen UniversityShenzhen 518060China

Removal of boric acid from seawater and wastewater using.reverse osmosis membrane technolog.es is imperative and yet remains inadequately addressed by current commercial *** research efforts performed post-modification of reverse osmosis membranes to enhance boron rejection,which is usually accompanied by substantial sacrifice in water *** study delves into the surface eng.neering.of low-pressure reverse osmosis membranes,aiming.to elevate boron removal efficiency while maintaining.optimal salt rejection and water *** were modified by the self-polymerization and co-deposition of dopamine and polystyrene sulfonate at varying.ratios and *** surfaces became smoother and more hydrophilic after *** optimum membrane exhibited a water permeability of 9.2±0.1 L·m^(-2)·h^(-1)·bar^(-1),NaCl rejection of 95.8%±0.3%,and boron rejection of 49.7%±0.1% and 99.6%±0.3% at neutral and alkaline pH,*** water permeability is reduced by less than 15%,while the boron rejection is 3.7 times hig.er compared to the blank *** research provides a promising.avenue for enhancing.boron removal in reverse osmosis membranes and addressing.water quality concerns in the desalination process.

关键词： membrane low-pressure reverse osmosis boron surface eng.neering

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Prediction of Bandwidth of Metamaterial Antenna Using.Pearson Kernel-Based Techniques

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Computers, Materials & Continua 2024年第3期78卷 3449-3467页

作者： Sherly Alphonse S.Abinaya Sourabh paul School of Computer Science and Eng.neering Vellore Institute of TechnologyChennai600127India School of Electronics Eng.neering Vellore Institute of TechnologyChennai600127India

The use of metamaterial enhances the performance of a specific class of antennas known as metamaterial *** radiation cost and quality factor of the antenna are influenced by the size of the *** antennas allow for the circumvention of the bandwidth restriction for small *** parameters have recently been predicted using.machine learning.alg.rithms in existing.*** learning.can take the place of the manual process of experimenting.to find the ideal simulated antenna *** accuracy of the prediction will be primarily dependent on the model that is *** this paper,a novel method for forecasting.the bandwidth of the metamaterial antenna is proposed,based on using.the Pearson Kernel as a standard *** with these new approaches,this paper sug.ests a unique hypersphere-based normalization to normalize the values of the dataset attributes and a dimensionality reduction method based on the Pearson kernel to reduce the dimension.A novel alg.rithm for optimizing.the parameters of Convolutional Neural Network(CNN)based on improved Bat Alg.rithm-based Optimization with Pearson Mutation(BAO-PM)is also presented in this *** prediction results of the proposed work are better when compared to the existing.models in the literature.

关键词： Antenna pearson optimization bandwidth metamaterial

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Improving.Heat Transfer in Parabolic Troug. Solar Collectors by Mag.etic Nanofluids

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Energ. Eng.neering 2024年第4期121卷 835-848页

作者： Ritesh Sing. Abhishek g.pta Akshoy Ranjan paul Bireswar paul Suvash C.Saha Department of Applied Mechanics Motilal Nehru National Institute of Technology AllahabadPrayagrajIndia Department of Mechanical and Mechatronic Eng.neering University of Technology SydneySydneyAustralia

A parabolic troug. solar collector(PTSC)converts solar radiation into thermal ***,low thermal efficiency of PTSC poses a hindrance to the deployment of solar thermal power *** performance of PTSC is enhanced in this study by incorporating.mag.etic nanoparticles into the working.*** circular receiver pipe,with dimensions of 66 mm diameter,2 mm thickness,and 24 m leng.h,is exposed to uniform temperature and velocity *** working.fluid,Therminol-66,is supplemented with Fe3O4 mag.etic nanoparticles at concentrations rang.ng.from 1%to 4%.The finding. demonstrate that the inclusion of nanoparticles increases the convective heat transfer coefficient(HTC)of the PTSC,with hig.er nanoparticle volume fractions leading.to g.eater heat transfer but increased pressure *** thermal enhancement factor(TEF)of the PTSC is positively affected by the volume fraction of nanoparticles,both with and without a mag.etic ***,the scenario with a 4%nanoparticle volume fraction and a mag.etic field streng.h of 250 g.exhibits the hig.est TEF,indicating.superior thermal *** finding. offer potential avenues for improving.the efficiency of PTSCs in solar thermal plants by introducing.mag.etic nanoparticles into the working.fluid.

关键词： Parabolic troug. solar collector(PTSC) mag.etic nanofluid(MNF) heat transfer convective heat transfer coefficient(HTC) thermal enhancement factor(TEF)

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