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Late neoproterozoic to early Cambrian high-grade metamorphism from Mikir Hills(Assam-Meghalaya gneissic Complex,northeast India):Implications for eastern Gondwana assembly

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Geoscience Frontiers 2024年第5期15卷 256-282页

作者： Rahul nag H.Hrushikesh nathan Cogné n.Prabhakar Department of Earth Sciences Indian Institute of Technology BombayPowaiMumbaiMaharastra 400076India Geological Survey of India Northeastern RegionGuwahatiAssam 781005India Géosciences Rennes UMR6118CNRS Universitéde RennesFrance

Mikir Hills region,which represents the eastern segment of the Assam-Meghalaya Gneissic Complex(AMGC)in northeast India,constitutes part of the Eastern *** Mikir Hills preserves multiple metamorphic and magmatic events ranging from Early Mesoproterozoic to Early *** of these events,documenting the late neoproterozoic to early Cambrian tectonothermal events is helpful in correlating the continental blocks of Eastern *** present an integrated study involving field relations,petrology,P-T history and zircon-monazite geochronology of hitherto poorly studied pelitic and quartzo-feldspathic gneisses from the Mikir Hills *** gneisses have experienced at least three deformation events(D_(1),D_(2) and D_(3))with dominant foliation indicated by EnE-WSW striking and shallow-moderately dipping(neissic *** peak metamorphism in pelitic and quartzo-feldspathic gneisses is characterized by garnet(core)-K-feldspar-sillimanite-plagioclase-bio tite-rutile-quartz-ilmenite-melt and garnet-plagioclase-K-feldspar-biotite-quartz-ilmenite-melt assemblages,*** application of thermobarometric methods constrains the peak P-T conditions of 7.5-8.4 kbar at 674-778℃and 6.7-7.4 kbar at 601-618℃for pelitic and quartzofeldspathic gneisses,*** results are consistent with the values estimated using phase equilibria modelling and melt reintegration *** results of pseudosection modelling suggests a clockwise P-T path for pelitic gneisses involving migmatisation during peak metamorphism followed by near isothermal decompression from 8.0 to 8.6 kbar at 768-780℃to 4.0-5.0 kbar at 720-765℃.In contrast,quartzo-feldspathic gneisses preserved slightly lower peak P-T conditions at 3.8-4.6 kbar and 590-650℃.The U-Pb zircon dating of migmatised pelitic and quartzo-feldspathic gneisses yielded concordant ages of 1647±11 Ma and 1590±7 Ma,*** dates represent the inherited igneous protolith components,possibly

关键词： Gondwana Assam-Meghalaya Gneissic Complex Migmatisation neoproterozoic Geochronology P-T-t history

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Measurement of yields and angular distributions ofγ-quanta from the interaction of 14.1 MeV neutrons with oxygen,phosphorus,and sulfur

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Chinese Physics C 2024年第3期48卷 79-92页

作者： D.n.Grozdanov n.A.Fedorov S.B.Dabylova Yu.n.Kopatch I.n.Ruskov V.R.Skoy T.Yu.Tretyakova C.Hramco P.I.Kharlamov G.V.Pampushik P.G.Filonchik A.V.Andreev Joint Institute for nuclear Research(JInR) DubnaRussia Institute for nuclear Research and nuclear Energy Bulgarian Academy of SciencesSofiaBulgaria Faculty of Physics Lomonosov Moscow State UniversityMoscowRussia L.n.Gumilyov Eurasian national University AstanaKazakhstan Skobeltsyn Institute of nuclear Physics Moscow State UniversityMoscowRussia Institute of Chemistry of Moldova ChisinauRepublic of Moldova Moscow Institute of Physics and Technology MoscowRussia

A study of the inelastic scattering of neutrons with an energy of 14.1 MeV on the nuclei of oxygen,phosphorus,and sulfur was performed at the TAnGRA facility at JInR(Dubna).The experiment aimed to refine existing data and obtain new data on the yields and angular distributions ofγ-quanta emitted by the studied nuclei due to neutron-induced nuclear reactions using the tagged neutron *** types of detector systems were used to registerγ-***γ-ray yields were measured using a high-purity germanium(HPGe)*** angular distributions ofγ-rays were obtained using a system of 18 scintillation detectors based on bismuth germanite Bi_(4)Ge_(3)O_(12)(BGO)located around the *** performed experiments measured the yields of two transitions for the reaction of tagged neutrons with 16O,nine transitions for the reaction with ^(31)P,and nine transitions for the reaction with ^(32)S for the first *** angular anisotropy of theγ-radiation accompanying the inelastic scattering of neutrons with an energy of 14.1 MeV on ^(31)P nuclei was also measured for the first time.

关键词： tagged neutron method yields of gamma-quanta high-resolution gamma-spectrometry neutron-nuclear reactions neutron scattering

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Hard life for sons in the nest?Sex-dependent offspring mortality in Great Tits in urban and forest areas

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Avian Research 2024年第1期15卷 91-97页

作者： nora Agh Henriett Anna Dalvári Krisztián Szabó Ivett Pipoly András Liker HUn-REn-PE Evolutionary Ecology Research Group University of PannoniaH-8200VeszpremPf.1158.Hungary Behavioral Ecology Research Group Center for Natural SciencesUniversity of PannoniaH-8200Pf.1158.VeszpremHungary Molecular Ecology Research Group Department of EcologyUniversity of Veterinary Medicine BudapestH-1400Pf.2.BudapestHungary Synlab Hungary Ltd. H-1211Weiss Manfr´ed Str.5-7BudapestHungary

Sex-biased mortality can occur in birds during development,for example due to sexual differences in energy requirement and/or environmental sensitivity,or the effects of sex hormones or sex differences in the expression of mutations linked to sex *** extent of sex-bias in mortality may also be related to environmental conditions that influence offspring development and *** areas often provide poorer conditions for nestling development resulting in higher offspring mortality compared to natural areas,which may accelerate sex differences in offspring mortality in *** test this hypothesis,we examined the sex ratio of dead offspring in Great Tits(Parus major),using 427 samples of unhatched eggs and dead nestlings collected in two urban and two forest sites between 2013 and *** ratio of males in the whole sample of dead offspring(56.9%)was significantly higher than expected by an 1:1 ratio,and the strongest sex biases were detected in urban areas(57.6%males)and in young nestlings(ng did not differ significantly among study sites and between offspring developmental stages.29.3%of unhatched eggs contained a visible embryo,and the proportion of embryo-containing unhatched eggs did not differ significantly between urban and forest study *** results suggest male-biased offspring mortality in Great Tits,and highlight the need of large datasets to detect subtle differences between habitats and developmental stages.

关键词： Great Tit Urbanization nestling mortality Sex related differences

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Effectiveness of external prestressing in enhancing the non-ductile hanger failure mechanism in reinforced concrete inverted T-beams

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 1050-1065页

作者： Ahmed M.ATTA Reda n.BEHIRY Mohammed I.HARAZ Structural Engineering Department Faculty of EngineeringTanta UniversityTanta 33511Egypt nile Higher Institute for Engineering and Technology Mansoura 11001Egypt

Recently,inverted T-beams have been used in reinforced concrete(RC)bridges to support transverse precast *** T-beams,contrary to practice with conventional beams,are loaded on the flanges upper *** loading configuration causes hanger failure due to the generation of vertical tensile stresses near the bottom of the *** key purpose of this study is to investigate the efficiency of vertical external prestressing stainless-steel bars in mitigating non-ductile hanger failure in reinforced concrete inverted *** experimental study on six inverted-T beams,including two un-strengthened specimens,was carried *** study showed that the value of the prestressing level had a considerable impact on the performance of hanger mechanism in relation to crack pattern,ultimate loads,cracking behavior,load-deflection,strains,and *** experimental results indicated that the suggested method for strengthening inverted T-beams had efficacy in reducing the seriousness of the non-ductile hanger failure and resulted in a strength increase of up to 53% when compared to that of the un-strengthened ***,two analytical models for estimating the hanger capacity and the average crack width of the strengthened RC inverted T-beams were *** models that were proposed exhibited a high degree of agreement with the experimental results.

关键词： RC bridges inverted T-beams strengthening hanger failure external prestressing

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In-situ study of the microstructure evolution during tension of a Mg-Y-Zn-Al alloy processed by rapidly solidified ribbon consolidation technique

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Journal of Magnesium and Alloys 2024年第5期12卷 2024-2040页

作者： Jeno Gubicza Kristián Máthis Péter nagy Péter Jenei Zoltán Hegedus Andrea Farkas Jozef Vesely Shin-ichi Inoue Daria Drozdenko Yoshihito Kawamura Department of Materials Physics Faculty of ScienceEotvos Loránd UniversityPázmány P.sétány 1/ABudapest H-1117Hungary Department of Physics of Materials Faculty of Mathematics and PhysicsCharles UniversityKe Karlovu 512116 Praha 2Czech Republic Deutsches Elektronen-Synchrotron DESY Notkestr.85Hamburg 22603Germany Magnesium Research Center Kumamoto University2-39-1 KurokamiChuo-kuKumamoto 860-8555Japan

Mg-Y-Zn-Al alloys processed by rapidly solidified ribbon consolidation(RSRC)technique exhibit an exceptional mechanical performance indicating promising application *** material has a bimodal microstructure consisting of fine recrystallized and coarse non-recrystallized grains with solute-rich stacking faults forming cluster arranged layers(CALs)and nanoplates(CAnaPs),or complete long period stacking ordered(LPSO)*** order to reveal the deformation mechanisms,in-situ synchrotron X-ray diffraction line profile analysis was employed for a detailed study of the dislocation arrangement created during tension in Mg-0.9%Zn-2.05%Y-0.15%Al(at%)*** uncovering the effect of the initial microstructure on the mechanical performance,additional samples were obtained by annealing of the as-consolidated specimen at 300 and 400℃ for 2 *** heat treatment at 300℃ had no significant effect on the initial microstructure,its evolution during tension and,thus,the overall deformation behavior under tensile *** the other hand,annealing at 400℃ resulted in a significant increase of the recrystallized grains fraction and a decrease of the dislocation density,leading to only minor degradation of the mechanical *** maximum dislocation density at the failure of the samples corresponding to the plastic strain of 10-25% was estimated to be about 16-20×10^(14)m^(-2).The diffraction profile analysis indicated that most dislocations formed during tension were of non-basal and pyramidal types,what was also in agreement with the Schmid factor values revealed independently from orientation *** was also shown that the dislocation-induced Taylor hardening was much lower below the plastic strain of 3% than above this value,which was explained by a model of the interaction between prismatic dislocations and CAnaPs/LPSO plates.

关键词： Mg-Zn-Y-Al alloy Long period stacking ordered(LPSO)phase Cluster arranged nanoplates(CAnaPs) Annealing Tension Dislocation density Hardening

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Deep learning for broadleaf weed seedlings classification incorporating data variability and model flexibility across two contrasting environments

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Artificial Intelligence in Agriculture 2024年第2期12卷 29-43页

作者： Lorenzo León Cristóbal Campos Juan Hirzel Instituto de Investigaciones Agropecuarias(InIA) INIA QuilamapuAvda.Vicente Méndez 515ChillánChile Fundacion ObservatorioÑuble Arauco 340ChillanChile

The increasing deployment of deep learning models for distinguishing weeds and crops has witnessed notable strides in agricultural ***,a conspicuous gap endures in the literature concerning the training and testing of models across disparate environmental *** methodologies either delineate a single dataset distribution into training,validation,and testing subsets or merge datasets from diverse condi-tions or distributions before their division into the *** study aims to ameliorate this gap by extending to several broadleaf weed categories across varied distributions,evaluating the impact of training convolutional neural networks on datasets specific to particular conditions or distributions,and assessing their performance in entirely distinct settings through three *** evaluating diverse network architectures and training approaches(finetuning versus feature extraction),testing various architectures,employing different training strategies,and amalgamating data,we devised straightforward guidelines to ensure the model's deployability in contrasting environments with sustained precision and *** Experiment 1,conducted in a uniform environment,accuracy ranged from 80%to 100%across all models and training strategies,with finetune mode achieving a superior performance of 94%to 99.9%compared to the feature extraction mode at 80%to 92.96%.Experiment 2 underscored a significant performance decline,with accuracy fig-ures between 25%and 60%,primarily at 40%,when the origin of the test data deviated from the train and valida-tion *** 3,spotlighting dataset and distribution amalgamation,yielded promising accuracy metrics,notably a peak of 99.6%for Resnet in finetuning mode to a low of 69.9%for InceptionV3 in feature extraction *** pivotal findings emphasize that merging data from diverse distributions,coupled with finetuned training on advanced architectures like Resnet and Mobilenet,markedly enhances

关键词： Artificial neural networks Deep learning Transfer learning Precision farming Feature extraction Finetuning Generalization Out-of-domain distribution Domain adaptation Multi-domain learning

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Chi-square automatic interaction detection(CHAID)analysis of the use of safety goggles and face masks as personal protective equipment(PPE)to protect against occupational biohazards

Journal of Biosafety and Biosecurity

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Journal of Biosafety and Biosecurity 2024年第2期6卷 125-133页

作者： Raúl Aguilar-Elena Juán JoséAgún-González Universidad Internacional de Valencia ValenciaSpain

Background:This study represents the first Spanish investigation to rigorously evaluate compliance with the use of safety goggles and face masks as essential personal protective equipment(PPE)in companies with workplaces involving exposure to biological ***:This study aimed to examine the degree of use of face masks and safety goggles as personal protective equipment(PPE),the factors that influence their use,and the profile of workers exposed to occupational biological agents in Spanish companies in the health sector,farming sector,meat industry,waste treatment plants,food industry,and veterinary ***:We conducted a cross-sectional descriptive study involving 590 Spanish workers from 51 *** developed a 34-item questionnaire to assess workers’perception of risk related to exposure to biological agents in their *** the questions,three were designed to measure the degree of use of key protective equipment in sectors with biological agent exposure:protective gloves,safety goggles or face *** only analyzed safety goggles and face *** performed various statistical analyses,including Cronbach’s alpha,frequency of endorsement,content validity ratio using Lawshe’s method,varimax rotation,the Kaiser-Meyer-Olkin test,and Bartlett’s sphericity test,to assess the internal consistency and reliability of the ***,we employed a chi-square automatic interaction detection(CHAID)segmentation analysis,using workers’responses regarding their attitudes toward safety goggles and face mask usage as PPE for protection against biological risks,with demographic variables as independent ***:In the current study,CHAID analysis revealed that workers exposed to group 2 biological agents used more safety goggles and face shields compared with workers exposed to other groups of biological ***,workers in laboratories and the food industry used face masks more than workers of other ***

关键词： PPE Safety googles and breath mask CHAID Biological Agents Occupational Biosafety

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Large dinosaur egg accumulations and their significance for understanding nesting behaviour

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Geoscience Frontiers 2024年第5期15卷 467-488页

作者： L.Ezquerro R.Coimbra B.Bauluz C.núñez-Lahuerta T.Román-Berdiel M.Moreno-Azanza Departamento de Geodinámica Estratigrafía y PaleontologíaFacultad de Ciencias GeológicasUniversidad Complutense de MadridC/JoséAntonio Novais1228040MadridSpain Aragosaurus-IUCA:Recursos Geológicos y Paleoambientales.Departamento de Ciencias de la Tierra.Facultad de Ciencias Universidad de ZaragozaC/Pedro Cerbuna 1250009 ZaragozaSpain Museu da Lourinha LourinhaPortugal GeoBioTec Department of Earth SciencesNOVA School of Science and TechnologyUniversidade Nova de LisboaCaparicaPortugal GeoBioTec Departamento de GeocienciasUniversidade de AveiroAveiroPortugal Insitut Catalàde Paleoecologia Humana i EvolucióSocial(IPHES-CERCA) Zona Educacional 4Campus Sescelades URV(Edifici W3)43007 TarragonaSpain Departament d´Història i Història de l´Art Universitat Rovira i VirgiliAv.Catalunya 3543002 TarragonaSpain Geotransfer IUCA Departamento de Ciencias de La TierraFacultad de CienciasUniversidad de ZaragozaZaragozaSpain

The accurate identification of dinosaur egg accumulations as nests or clutches is crucial for understanding the reproductive behaviour of these extinct ***,existing methods often rely on the presence of complete eggs and embryo remains,and sedimentological criteria that are only applicable to well-structured *** this study,we introduce an innovative approach to characterize egg accumulations in structureless sediments,where traditional nest structures may not be *** methodology employs a unique combination of sedimentological,taphonomic,geochemical,and geophysical proxies for the study of egg *** applied this approach to the egg accumulation from Paimogo(Jurassic,Portugal),traditionally interpreted as a *** findings reveal that the Paimogo egg assemblage is a secondary deposit,resulting from a flooding event in a fluvial plain that dismantled several allosauroid and crocodylomorph *** eggshell vapor conductance results,coupled with sedimentological evidence,suggest that allosauroid dinosaurs buried their eggs in the dry terrain of overbank areas close to a main channel during the breeding season,likely during the dry season to prevent the embryos from *** research underscores the necessity of multidisciplinary approaches in interpreting egg accumulations and offers a novel methodology for studying these accumulations in structureless *** findings provide new insights into the breeding behaviour and nesting preferences of these extinct organisms,contributing to our understanding of dinosaur ecology.

关键词： Breeding behaviour Theropod Taphonomy Stable isotopes Magnetic susceptibility Jurassic

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Effects of site preparation methods on soil physical properties and outplanting success of coniferous seedlings in boreal forests

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Journal of Forestry Research 2024年第2期35卷 70-80页

作者： Aleksey S.Ilintsev Elena n.nakvasina Alexander P.Bogdanov northern Research Institute of Forestry 13 Nikitova Str.Arkhangelsk 163062Russian Federation Department of Silviculture and Forest Management Northern(Arctic)Federal University Named After M.V.LomonosovSevernoy Dviny Emb.17Arkhangelsk 163002Russian Federation

This study assessed the effect of patch scarification and mounding on the physical properties of the root layer and the success of tree planting in various types of *** study was conducted on 12 forest sites in taiga forests of the European part of Russia.A total of 54 plots were set up to assess seedling survival;root collar diameter,height,and heigh increment were measured for 240 seedlings to assess *** the rooting layer,240 soil samples were taken to determine physical *** study showed that soil treatment methods had no effect on bulk density and total porosity in Cladina ***,reduced soil moisture was noted,particularly in mounds,resulting in increased *** Myrtillus sites,there were increased bulk density,reduced soil moisture,and total porosity in the *** treatment in Polytrichum sites resulted in reduced soil moisture and increased aeration *** the Myrtillus and Polytrichum sites,patch scarification had no effects on physical *** Polytrichum sites,survival rates,heights,and heigh increments of bareroot norway spruce seedlings in mounds were higher than in patches;however,the same did not apply to *** Cladina and Myrtillus sites,there was no difference in growth for bareroot and containerised seedlings with different soil *** conditions and soil types should be considered when applying different soil treatment methods to ensure high survival rates and successful seedling growth.

关键词： Boreal forests Mechanical site preparation Patch scarification Mounding Soil properties Containerised seedlings Bareroot seedlings

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numerical Simulation of Thermocapillary Convection with Evaporation Induced by Boundary Heating

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Fluid Dynamics & Materials Processing 2024年第7期20卷 1667-1686页

作者： O.n.Goncharova V.B.Bekezhanova Altai State University Institute of Mathematics and Information TechnologiesBarnaul656049Russia Institute of Computational Modelling SB RAS Department of Differential Equations of MechanicsKrasnoyarsk660036Russia

The dynamics of a bilayer system filling a rectangular cuvette subjected to external heating is *** influence of two types of thermal exposure on the flow pattern and on the dynamic contact angle is *** particular,the cases of local heating from below and distributed thermal load from the lateral walls are *** simulation is carried out within the frame of a two-sided evaporative convection model based on the Boussinesq approximation.A benzine–air system is considered as reference *** variation in time of the contact angle is described for both heating *** lateral heating,near-wall boundary layers emerge together with strong convection,whereas the local thermal load from the lower wall results in the formation of multicellular motion in the entire volume of the fluids and the appearance of transition regimes followed by a steady-state *** results of the present study can aid the design of equipment for thermal coating or drying and the development of methods for the formation of patterns with required structure and morphology.

关键词： Thermocapillary convection two-phase system numerical modeling contact angle

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