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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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Learning the optimal power flow:environment design matters

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energy and AI 2024年第3期17卷 432-443页

作者： Thomas Wolgast Astrid nieße Carl von Ossietzky Universität Oldenburg Department of Computing ScienceDigitalized Energy SystemsAmmerländer Heerstraße 114-118Oldenburg26129Germany

To solve the optimal power flow(OPF)problem,reinforcement learning(RL)emerges as a promising new ***,the RL-OPF literature is strongly divided regarding the exact formulation of the OPF problem as an RL *** this work,we collect and implement diverse environment design decisions from the literature regarding training data,observation space,episode definition,and reward function *** an experimental analysis,we show the significant impact of these environment design options on RL-OPF training ***,we derive some first recommendations regarding the choice of these design *** created environment framework is fully open-source and can serve as a benchmark for future research in the RL-OPF field.

关键词： Reinforcement learning Optimal power flow environment design economic Dispatch Voltage control Reactive power market

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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(es).However,the sex ratios of dead offspring 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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Integrated Zoology calls for papers:special issue on wildlife diseases and parasitology

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Integrative Zoology 2024年第3期19卷 424-425页

作者： nubia e.MATTA Wenhua XIOnG Department of Biology Universidad Nacional de ColombiaBogotaColombia International Society of Zoological Sciences BeijingChina Institute of Zoology Chinese Academy of SciencesBeijingChina

The VI International Conference on Malaria and Other Blood Parasites of Wildlife and the III International Symposium of the Wildlife Diseases Research network are scheduled to be held in Medellín,Colombia,from november 26 to 30 of 2024(https://***/lLW79).It will be hosted by the University of Antioquia’s Department of Biology and the Universidad nacional de Colombia Department of Biology.

关键词： Blood Malaria diseases

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Optimization of Random Feature Method in the High-Precision Regime

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Communications on Applied Mathematics and Computation 2024年第2期6卷 1490-1517页

作者： Jingrun Chen Weinan e Yifei Sun School of Mathematical Sciences and Suzhou Institute for Advanced Research Suzhou 215006JiangsuChina University of Science and Technology of China Hefei 230026AnhuiChina Center for Machine Learning Research and School of Mathematical Sciences Peking UniversityBeijing 100871China AI for Science Institute Beijing 100084China School of Mathematical Sciences Soochow UniversitySuzhou 215006JiangsuChina

Machine learning has been widely used for solving partial differential equations(PDes)in recent years,among which the random feature method(RFM)exhibits spectral accuracy and can compete with traditional solvers in terms of both accuracy and ***,the optimization problem in the RFM is more difficult to solve than those that arise in traditional *** the broader machine-learning research,which frequently targets tasks within the low-precision regime,our study focuses on the high-precision regime crucial for solving *** this work,we study this problem from the following aspects:(i)we analyze the coeffcient matrix that arises in the RFM by studying the distribution of singular values;(ii)we investigate whether the continuous training causes the overfitting issue;(ii)we test direct and iterative methods as well as randomized methods for solving the optimization *** on these results,we find that direct methods are superior to other methods if memory is not an issue,while iterative methods typically have low accuracy and can be improved by preconditioning to some extent.

关键词： Random feature method(RFM) Partial differential equation(PDe) Least-squares problem Direct method Iterative method

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Olfactory immune response to SARS-CoV-2

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Cellular & Molecular Immunology 2024年第2期21卷 134-143页

作者： Sebastian A.Wellford e.Ashley Moseman Department of Integrative Immunobiology Duke University School of MedicineDurhamNCUSA

numerous pathogens can infect the olfactory tract,yet the pandemic caused by SARS-CoV-2 has strongly emphasized the importance of the olfactory mucosa as an immune *** in the nasal passages,the olfactory mucosa is directly exposed to the environment to sense airborne odorants;however,this also means it can serve as a direct route of entry from the outside world into the *** a result,olfactotropic infections can have serious consequences,including dysfunction of the olfactory system,CnS invasion,dissemination to the lower respiratory tract,and transmission between *** research has shown that a distinctive immune response is needed to protect this neuronal and mucosal tissue.A better understanding of innate,adaptive,and structural immune barriers in the olfactory mucosa is needed to develop effective therapeutics and vaccines against olfactotropic microbes such as ***,we summarize the ramifications of SARS-CoV-2 infection of the olfactory mucosa,review the subsequent immune response,and discuss important areas of future research for olfactory immunity to infectious disease.

关键词： Mucosal immunology neuroimmunology Infectious Disease Sars-CoV-2

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Removal of As(V)in the presence of Cr(VI)in contaminated water from the Bajio region of Mexico using ferrihydrite-functionalized graphene oxide(GOFH):A case study

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emerging Contaminants 2024年第3期10卷 134-144页

作者： D.R.Joya-Cardenas J.P.Rodríguez-Caicedo M.A.Corona-Rivera n.Saldana-Robles C.e.Damian-Ascencio A.Saldana-Robles Graduate Program in Biosciences University of GuanajuatoIrapuato36500Mexico Facultad de Ingenierías y Tecnologías Instituto XeriraUniversidad de SantanderBucaramanga680003Colombia Chemical engineering Unit Academic Multidisciplinary Region Altiplano UAMRA.Autonomous University of San Luis PotosíMatehualaSan Luis Potosí78000Mexico Department of Agricultural engineering University of GuanajuatoIrapuato36500Mexico Department of Mechanical engineering University of GuanajuatoSalamanca36800Mexico Mechanical engineering Department Virginia TechBlacksburgVA24061USA

The presence of heavy metals such as arsenic(As)and chromium(Cr)can be considered one of the most toxic heavy *** study aims to develop and evaluate a graphene oxide(GO)based material functionalized with ferrihydrite for the removal of As(V)in the presence of Cr(VI).The adsorbent ferrihydrite-functionalized graphene oxide(GOFH)was characterized by SeM,FTIR,XRD,XPS,surface charge,BeT and *** adsorption capacities for As(V)and Cr(VI)were 160 and 66 mg g^(-1)respectively at pH 4 and 298 K,fitting the Langmuir *** binary systems,GOFH adsorbed As(V)with an adsorption capacity of 137 mg g^(-1)in the presence of 20 mg L^(-1)Cr(VI)at room *** analysis revealed an exothermic and spontaneous ***,GOFH effectively removed several coexisting anions from groundwater,including SO_(4)^(2-),CO_(3)^(2-)and Cl^(-).This work evidences the potential of GOFH for competitive adsorption of priority pollutants from complex *** GOFH material represents a technically and economically viable technology for application in groundwater decontamination,as it requires inexpensive precursors and ambient conditions during synthesis and operation.

关键词： Competition Ions Contamination Groundwater Adsorption capacity

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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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