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The Siberian Traps and the End-Permian mass extinction:a critical review

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Chinese Science Bulletin 2009年第1期54卷 20-37页

作者： Andy SAUNDERS marc REICHOW Department of Geological Sciences University of Leicester

The association between the Siberian Traps,the largest continental flood basalt province,and the largest-known mass extinction event at the end of the Permian period,has been strengthened by re-cently-published high-precision 40Ar/39Ar dates from widespread localities across the Siberian prov-ince[1]. We argue that the impact of the volcanism was amplified by the prevailing late Permian envi-ronmental conditions―in particular,the hothouse climate,with sluggish oceanic circulation,that was leading to widespread oceanic anoxia. Volcanism released large masses of sulphate aerosols and carbon dioxide,the former triggering short-duration volcanic winters,the latter leading to long-term warming. Whilst the mass of CO2 released from individual eruptions was small compared with the total mass of carbon in the atmosphere-ocean system,the long ‘mean lifetime’ of atmospheric CO2,com-pared with the eruption flux and duration,meant that significant accumulation could occur over periods of 105 years. Compromise of the carbon sequestration systems (by curtailment of photosynthesis,de-struction of biomass,and warming and acidification of the oceans) probably led to rapid atmospheric CO2 build-up,warming,and shallow-water anoxia,leading ultimately to mass extinction.

关键词：西伯利亚二叠纪温室气候海洋缺氧 CO2 SO2

How We Will Discover Sentience in AI

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Journal of Social Computing 2023年第3期4卷 181-192页

作者： marc M.Anderson the LORIA UMR 7503Universitéde LorraineInria the CNRS Vandoeuvre-lès-Nancy 54506France

This paper explores the question of how we can know if Artificial Intelligence(AI)systems have become or are becoming *** an overview of some arguments regarding AI sentience,it proceeds to an outline of the notion of negation in the philosophy of Josiah Royce,which is then applied to the arguments already ***’s notion of the primitive dyadic and symmetric negation relation is shown to bypass such *** negation relation and its expansion into higher types of order are then considered with regard to how,in small variations of active negation,they would disclose sentience in AI ***,I argue that the much-hyped arguments and apocalyptic speculations regarding Artificial General Intelligence(AGI)takeover and similar scenarios,abetted by the notion of unlimited data,are based on a fundamental misunderstanding of how entities engage their ***,limitation,proceeding from the symmetric negation relation,expands outward into higher types of order in polyadic relations,wherein the entity self-limits and creatively moves toward uniqueness.

关键词： artificial intelligence sentience consciousness negation Josiah Royce logic Artificial General Intelligence(AGI)

New insights into the control of symbiotic nitrogen fixation by carbon supply

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Molecular Plant 2023年第11期16卷 1724-1726页

作者： marc Lepetit Renaud Brouquisse Institut Sophia Agrobiotech INRAEUniversite Cote d'AzurCNRS06903 Sophia-AntipolisFrance

The interaction between legumes and rhizobium-type bacteria allows symbiotic nitrogen fixation(SNF).Symbiosis takes place in a new root organ,the nodule,in which the plant host fuels the bacteria differentiated into bacteroids with dicarboxylic acids,enabling their active carbon and energy metabolisms(Figure 1).In addition,the plant maintains the bacteroids in microoxic conditions allowing the nitrogenase to reduce atmospheric nitrogen(N_(2))to ammonia(NH_(3)).Ammonia is not assimilated in the bacteroids but is subsequently transferred into the surrounding plant cells,where it combines with carbon(C)skeletons through the glutamine synthetase/glutamate synthase *** amino acids and/or ureides are finally distributed from the root to the to the whole plant.

关键词： Figure insight skeleton

Boundary layer influence on ship model tests in extremely shallow and confined water

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Journal of Hydrodynamics 2023年第2期35卷 365-378页

作者： Evert Lataire Asif Raza marc Vantorre Guillaume Delefortrie Maritime Technology Division Ghent UniversityGhentBelgium ANAST University of LiègeLiègeBelgium Flanders Hydraulics Research AntwerpBelgium

Ships sailing in shallow and/or confined water(when calling a harbour or other berthing areas),will experience a different behaviour due to the interaction with vertical and/or horizontal *** other hydrodynamic changes induced in confined water,the lateral ship-bank interaction force changes its sign at a critical distance between ship and bank or ***,this distance and its effects on model test results have not been quantified in the *** investigate the shallow water hydrodynamics coupled with bank effects,systematic model tests were carried out at Flanders Hydraulics Research(FHR)with different ship *** following parameters were systematically varied:water depth,lateral position,speed,and propeller *** change of the ship-bank induced lateral force from an attraction force in medium-deep and shallow water to a repulsion force in extremely shallow water conditions,can be ascribed to the interaction of the boundary layers of the ship model and the environment(tank and installed banks).In this article,a mathematical model is proposed for the critical distance in terms of boundary layer influence *** indicates the range where the model tests are influenced by the horizontal or vertical restrictions combined with the propeller’s dynamic ***,the expression has also been extended to describe the relationship between full-scale ship length and water depth with the boundary layer influence *** to lower Reynolds numbers and relatively thicker boundary layers at model scale,upscaling of the model test results,according to Froude’s law,may provide erroneous *** influence of the boundary layer initiates at a relatively higher under keel clearance(UKC)for a smaller ship model compared with a larger ship ***,the boundary layer’s influence with respect to ship model length should be considered during model testing.

关键词： Shallow water hydrodynamics bank effects boundary layer model tests mathematical model

Expression of miR‑138 in cryopreserved bovine sperm is related to their fertility potential

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Journal of Animal Science and Biotechnology 2023年第6期14卷 2383-2394页

作者： Albert Salas‑Huetos Jordi Ribas‑Maynou Yentel Mateo‑Otero Carolina Tamargo marc Llavanera marc Yeste Unit of Cell Biology Department of BiologyFaculty of SciencesUniversity of GironaGirona 17003Spain. Biotechnology of Animal and Human Reproduction(TechnoSperm) Institute of Food and Agricultural TechnologyUniversity of GironaGirona 17003Spain. Department of Nutrition Harvard T.H.Chan School of Public HealthHarvard UniversityBostonMA 02115USA. Consorcio CIBER M.P.Fisiopatologia de la Obesidad y Nutricion(CIBERobn)Instituto de Salud Carlos III(ISCIII)Madrid 28029Spain. Present Address:Unit of Preventive Medicine and Public Health Faculty of Medicine and Health SciencesUniversitat Rovira i VirgiliReus 43201Spain. Department of Animal Selection and Reproduction The Regional Agri-Food Research and Development Service of Asturias(SERIDA)Gijon 33394Spain. Catalan Institution for Research and Advanced Studies(ICREA) Barcelona 08010Spain.

Background MicroRNAs(miRNAs)are small,single-stranded,non-coding RNA molecules of 22–24 nucleotides that regulate gene *** the last decade,miRNAs have been described in sperm of several mammals,including *** is known that miRNAs can act as key gene regulators of early embryogenesis in mice and humans;however,little is known about the content,expression,and function of sperm-borne miRNAs in early bovine *** this study,total sperm RNA was isolated from 29 cryopreserved sperm samples(each coming from a separate bull)using a RNeasy kit and treatment with DNase *** concentration and purity were determined through an Epoch spectrophotometer and an Agilent *** expression of 10 candidate miRNAs in bovine sperm(bta-miR-10a,bta-miR-10b,bta-miR-138,bta-miR-146b,bta-miR-19b,bta-miR-26a,bta-miR-34a,bta-miR-449a,bta-miR-495 and btamiR-7),previously identified in testis and/or epididymis,was evaluated with *** cel-miR-39-3p was used as a spike-in exogenous *** Mann–Whitney tests were run to evaluate which miRNAs were differentially expressed between bulls with high fertility[HF;non-return rates(NRR)ranging from 39.5 to 43.5]and those with subfertility(SF;NRR ranging from 33.3 to 39.3).Several sperm functionality parameters(e.g.,viability,membrane stability or oxygen consumption,among others)were measured by multiplexing flow cytometry and oxygen sensing *** RNA concentration and purity(260/280 nm ratio)(mean±SD)from the 29 samples were 99.3±84.6 ng/μL and 1.97±0.72,*** results confirmed the lack of RNA from somatic *** terms of the presence or absence of miRNAs,and after applying the Livak method,8 out of 10 miRNAs(bta-miR-10b,-138,-146b,-19b,-26a,-449a,-495,-7)were consistently detected in bovine sperm,whereas the other two(bta-miR-10a,and-34a)were ***,the relative expression of one miRNA(bta-miR-138)in sperm was significantly lower in the SF than in the HF gr

关键词： Bovine Fertility miRNAs Sperm

The structure of the human 4F2hc-LAT1 heteromeric amino acid transporter

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Science China(Life Sciences) 2019年第6期62卷 848-850页

作者： Dimitrios Fotiadis Jean-marc Jeckelmann Institute of Biochemistry and Molecular Medicine and Swiss National Centre of Competence in Research (NCCR) TransCureUniversity of Bern

Amino acids are biologically important molecules that serve as energy source, building blocks of proteins, precursors for metabolites and signaling compounds in all living *** of proteinogenic amino acids and related substances across biological membranes is mediated by membrane embedded proteins:the amino acid transporters. These membrane proteins belong to different solute carrier (SLC)families (http://***) and transfer amino acids in and out between compartments inside cells, between different cells and between organs. Amino acid transporters have diverse important physiological functions and their absence, overexpression and malfunction can lead to human diseases.

关键词： Amino acids important molecules functions and their absence

Variability of European beech wood density as influenced by interactions between treering growth and aspect

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Forest Ecosystems 2016年第3期3卷 165-173页

作者： Daniela Diaconu marc Wassenberg Heinrich Spiecker Chair of Forest Growth and Dendroecology Albert-Ludwigs-University

Background： Wood density is considered to be the most important predictor of wood quality but despite its importance, diffuse-porous tree species have been the subject of only a limited number of studies. The importance of European beech forests for Central Europe calls for profound research to examine the potential impact of a warmer climate on the quality of beech timber. Methods： In this study we analysed the influence of tree-ring width and tree-ring age on the wood density of beech, and whether the wood density response to these two parameters is modified by aspect. A linear mixed-effects model for wood density was constructed for mean density data measured with high frequency densitometry on stem discs from 72 beech trees sampled from two different aspects （northeast -NE and southwest -SW） of a valley in southwestern Germany. Results： Part of the variability of mean annual wood density was explained by cambial age： an increase in cambial age resulted in an increase in mean wood density. Tree-ring width and aspect had only a small influence on wood density, Wood density on the SW aspect was lower than on the NE with a difference of approximately 0.006 g/cm3. The between-tree variability was very high. Conclusions： The significant interaction between cambial age and aspect reflects the importance of site conditions at older tree ages： with increasing cambial age the difference between aspects becomes stronger. Our results give a better understanding of the importance of site conditions on the wood quality of beech.

关键词： Fagus sylvatica HF densitometry Wood quality Wood density Aspect

Experimental and Statistical Analysis of Fatigue Behavior in Zr-based Bulk Metallic Glass

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稀有金属材料与工程 2024年第11期53卷 3010-3016页

作者： Yao Zhifeng Qiao Jichao Pelletier Jean-marc Yao Yao School of Civil Engineering Xi'an University of Architecture&TechnologyXi'an 710055China Dongguan Sanhang Innovation Institute Dongguan 523808China School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi'an 710072China Institut National des Sciences Appliquées de Lyon Universitéde LyonLyon F-69621France School of Materials and Chemical Engineering Xi'an Technological UniversityXi'an710021China

Three-point bending fatigue experiments were conducted on a typical Zr-based bulk metallic glass(BMG)at ambient temperature to investigate the fatigue behavior under cyclic loading *** show that the stress amplitude-cycles to failure(S-N)curve of the Zr-based BMG is determined,and the fatigue endurance limit is 442 MPa(stress amplitude).To evaluate the probability-stress amplitude-cycles to failure(P-S-N)curve,an estimation method based on maximum likelihood was proposed,which relies on statistical principles to estimate the fatigue life of the material and allows for a reduction in the number of samples required,offering a cost-effective and efficient alternative to traditional testing *** experimental results align with the American Society for Testing and Materials(ASTM)standard,indicating the reliability and accuracy of this estimation method in evaluating the fatigue behavior of Zr-based BMG.

关键词： bulk metallic glass P-S-N curve fatigue test statistical analysis

Application of Kaiser Sepsis Calculator in culture-positive infants with early onset sepsis

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World Journal of Pediatrics 2021年第4期17卷 429-433页

作者： Gretchen Kopec marc Collin Anirudha Das Department of Neonatology University of Illinois College of MedicinePeoria campusPeoriaUSA Department of Neonatology MetroHealth Medical CenterClevelandUSA Department of Neonatology Cleveland Clinic Children’s Hospital9500 Euclid AvenueClevelandOH44195USA

Background Kaiser Sepsis Calculator(KSC)reduces antibiotic use,testing and intravenous infiltrates but there are concerns about the missed early onset sepsis(EOS)*** sought to apply the KSC score for culture-positive infants retrospectively in infants born in the last 10 years in our *** In a retrospective cohort study,the comparison groups were divided into Group A(no antibiotics recommended by KSC)and Group B(antibiotics recommended).Results Overall,17/24(71%)infants would have been started on antibiotics per KSC but 7/24(29%)would *** initial EOS risk was not significantly different between the groups(Group A *** B:0.44 vs.0.76,P=0.41),but the final risk score was(0.33 vs.9.41,P<0.001).In Group A(no antibiotics),3/7 infants became symptomatic between 9 and 42 *** There may be a potential delay in starting antibiotics in infants that are asymptomatic at birth while using KSC.

关键词： Early onset sepsis EOS Kaiser Sepsis Calculator Neonatal sepsis Neonate Newborn Blood culture