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Journal of Magnesium and Alloys 2024年第5期12卷 1931-1943页

作者： Farid Bahari-Sambran fernando carreno c.M.cepeda-Jiménez Alberto Orozco-caballero Physical Metallurgy Department CENIM-CSICAv.Gregorio del Amo 828040 MadridSpain Department of Mechanical Engineering Chemistry and Industrial DesignPolytechnic University of MadridRonda de Valencia 328012MadridSpain

The aim of this work is to predict,for the first time,the high temperature flow stress dependency with the grain size and the underlaid deformation mechanism using two machine learning models,random forest(RF)and artificial neural network(ANN).With that purpose,a ZK30 magnesium alloy was friction stir processed(FSP)using three different severe conditions to obtain fine grain microstructures(with average grain sizes between 2 and 3μm)prone to extensive superplastic *** three friction stir processed samples clearly deformed by grain boundary sliding(GBS)deformation mechanism at high *** maximum elongations to failure,well over 400% at high strain rate of 10^(-2)s^(-1),were reached at 400℃ in the material with coarsest grain size of 2.8μm,and at 300℃ for the finest grain size of 2μ***,the superplastic response decreased at 350℃ and 400℃ due to thermal instabilities and grain coarsening,which makes it difficult to assess the operative deformation mechanism at such *** work highlights that the machine learning models considered,especially the ANN model with higher accuracy in predicting flow stress values,allow determining adequately the superplastic creep behavior including other possible grain size scenarios.

关键词： Machine learning Artificial intelligence Magnesium alloys Superplasticity Friction stir processing Grain coarsening

Rotating effects on the photoionization cross-section of a 2D quantum ring

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communications in Theoretical Physics 2024年第10期76卷 153-159页

作者： carlos Magno O Pereira Frankbelson dos S Azevedo Luís fernando c Pereira Edilberto O Silva Departamento de Física Universidade Federal do Maranh?o

In this article, we investigate the nonrelativistic quantum motion of a charged particle within a rotating frame, taking into account the Aharonov–Bohm(AB) effect and a uniform magnetic field. Our analysis entails the derivation of the equation of motion and the corresponding radial equation to describe the system. Solving the resulting radial equation enables us to determine the eigenvalues and eigenfunctions, providing a clear expression for the energy levels. Furthermore,our numerical analysis highlights the substantial influence of rotation on both energy levels and optical properties. Specifically, we evaluate the photoionization cross-section with and without the effects of rotation. To elucidate the impact of rotation on the photoionization process of the system, we present graphics that offer an appealing visualization of the intrinsic nature of the physics involved.

关键词： Aharonov-Bohm effect photoionization cross-section quantum ring rotating effect

Polio eradication surveillance in Sri Lanka,2019-2023

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Asian Pacific Journal of Tropical Medicine 2024年第6期17卷 268-272页

作者： M.A.Y.fernando N.S.Madarasinghe c.Rangana N.Weerasinghe D.c.U.D.Weligamage J.I.Abeynayake Department of Medical Microbiology and Immunology Faculty of MedicineUniversity of ColomboSri Lanka Department of Virology Medical Research InstituteColombo 08Sri Lanka Medical Research Institute Colombo 08Sri Lanka

Objective:To evaluate the polio laboratory surveillance carried out from January,2019 to May,2023 by the Polio Regional Reference Laboratory,Sri ***:This retrospective study analyzed all stool samples received under the acute flaccid paralysis(AFP)and immunodeficient vaccine-derived poliovirus(VDPV)surveillance at Polio Regional Reference Laboratory,Sri Lanka from January,2019 to May,*** results of the testing methodologies were extracted from the laboratory data system,i.e.,poliovirus virus isolation,intra-typic differentiation/VDPV real time reverse transcriptase polymerase chain reaction(ITD/VDPV rRTPcR)and sequencing,along with the data on timing of reporting results,stool adequacy and *** was analyzed using descriptive ***:A total of 2141 stool samples from 1644 cases were received for AFP surveillance from Sri Lanka(93.61%),Maldives(1.52%),and immunodeficient VDPV(4.86%)*** polioviruses(19/1644,1.15%)and non-polio enteroviruses(73/1644,4.44%)were isolated,while Sabin-like 3 virus was detected in majority(12/19,63.15%)among the poliovirus *** polioviruses or circulating VDPVs were not detected among the *** all years of the study,the non-polio AFP detection rate was>1/100000 in children aged less than 15 years,whereas stool adequacy rate was>80%.All results were reported within 14 days of receipt,ensuring timely reporting as per global ***:The Polio Regional Reference Laboratory,Sri Lanka plays a vital role in maintaining the polio-free status in the country through its robust laboratory surveillance,while adhering to the surveillance ***-detection of wild polioviruses and circulating VDPV during the study period reinforces the polio-free status in the country.

关键词： Poliovirus Polio laboratory surveillance Regional reference laboratory Polio eradication

Important step towards an understanding of the exotic Z_(c)(3900)

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Science china(Physics,Mechanics & Astronomy) 2024年第9期67卷 199-200页

作者： c.Hanhart Institute for Advanced Simulation Forschungszentrum JulichJilich D-52425Germany

The Standard Model of particle physics,which contains the field theories for the electro-weak interaction(QED)and the strong interaction(QcD),is an extremely successful theory describing a huge variety of phenomena at... 详细信息

关键词： interaction atomic describing

The challenging management of malignant ureteral obstruction:Analysis of a series of 188 cases

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current Urology 2024年第1期18卷 34-42页

作者： Alberto Artiles Medina Inés Laso García fernando González Tello Sara Álvarez Rodríguez Manuel Hevia Palacios Marina Mata Alcaraz césar Mínguez Ojeda fernando Arias Funez Victoria Gómez Dos Santos Francisco Javier Burgos Revilla Department of Urology Hospital Universitario Ramón y CajalMadridSpain Department of Radiology Hospital Universitario Ramón y CajalMadridSpain

Background:Malignant ureteral obstruction(MUO)is a common condition that complicates the course of advanced *** aims of this study are to analyze the causes,management,and survival of patients with obstructive nephropathy due to malignant ureteric obstruction and to determine prognostic ***,we studied the complications and outcomes in patients who underwent urinary *** and methods:A retrospective study was conducted on patients with computed tomography-confirmed MUO between January 2016 and November ***,clinical,radiological,laboratory,and management data were *** curves were estimated using the Kaplan-Meier method,and univariate and multivariate cox proportional hazards models were used to test the association between parameters and ***:A total of 188 patients were *** mean age was 69.01 years(SD,14.95 years),and the majority(54.8%)were *** most common mechanism leading to MUO was compression by a pelvic mass(36.9%),and the 3 most frequent tumors causing MUO were prostate(17.6%),bladder(16.5%),and rectal cancer(11.7%).Forty-seven patients(25%)underwent urinary diversion:23(48.9%)underwent double-J stenting and 21(44.7%)underwent percutaneous *** most common reason for urinary diversion was acute kidney injury(53.3%).Recovery of renal function was observed in 55.8%of the patients after urinary *** most frequently identified complications after urinary diversion were urinary tract infection(24.4%),hematuria(17.0%),and urinary sepsis(14.9%).The median survival after hydronephrosis diagnosis was 6.43 months(interquartile range,1.91-14.81 months).In patients who underwent urinary decompression,the median survival after urinary diversion was 8.67 months(interquartile range,2.99-17.28 months).In the multivariate analysis,a lower grade of hydronephrosis and cancer cachexia negatively impacted ***:cancer patients with MUO have a poor pro

关键词： Hydronephrosis Ureteral obstruction Neoplasms Urinary diversion Survival Prognosis

Expression changes of mi RNA-regulated genes associated with the formation of the leafy head in cabbage

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Horticultural Plant Journal 2024年第4期10卷 1007-1019页

作者： Jorge Aleman-Baez Jose fernando Acevedo-Zamora Johan Bucher chengcheng cai Roeland E.Voorrips Guusje Bonnema Plant Breeding Wageningen University and ResearchWageningenThe Netherlands

The vegetative development of cabbage(Brassica oleracea ***)passes through seedling,rosette,folding and heading *** that form the rosette are large and mostly *** the following developmental stages,the plants produce leaves that curve inward to produce the leafy *** microRNAs and their target genes have been described participating in leaf development and leaf *** aim of this study is to investigate the role of miRNA-regulated genes in the transition from the rosette to the heading *** compared the mi RNA and gene abundances between emerging rosette and heading *** remove transcripts(miRNAs and genes)whose regulation was most likely associated with plant age rather than the change from rosette to heading stage,we utilized a non-heading collard green(*** ***)morphotype as *** resulted in 33 DEMs and 1998 DEGs with likely roles in the transition from rosette to heading stage in *** these 1998 DEGs,we found enriched GO terms related to DNA-binding transcription factor activity,transcription regulator activity,iron ion binding,and *** predicted the target genes of these 33 DEMs and focused on the subset that was differentially expressed(1998DEGs)between rosette and heading stage leaves to construct mi RNA-target gene interaction *** main finding is a role for miR396b-5p targeting two Arabidopsis thaliana orthologues of GROWTH REGULATING FAcTORs 3(GRF3)and 4(GRF4)in pointed cabbage head formation.

关键词： Brassica oleracea var.capitata RNA sequencing miRNA-target gene network leafy head formation

Potential of Bamboo Species Guadua trinii and Guadua angustifolia for Nanocellulose Production

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Journal of Renewable Materials 2024年第9期12卷 1541-1555页

作者： Agatha E.R.Prado Gárate fernando E.Felissia María cristina Area Teresa Suirezs María Evangelina Vallejos círculo de Investigación del Bambú Universidad Nacional Agraria La Molina(UNALM)Lima15026Perú Instituto de Materiales de Misiones(IMAM) Universidad Nacional de Misiones(UNaM)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Facultad de Ciencias ExactasQuímicas y Naturales(FCEQYN)Programa de Celulosa y Papel(PROCyP)Posadas3300Argentina Instituto de Materiales de Misiones(IMAM) Universidad Nacional de Misiones(UNaM)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Facultad de Ciencias Forestales(FCF)Eldorado3380Argentina

Non-traditional lignocellulosic materials are a significant resource for producing high-value products,including *** work studied the nanocellulose obtention from chemical pulps of the two fast-growing bamboo species,Guadua trinii,and Guadua *** pulps were produced by soda-anthraquinone(S)pulping from both autohydrolysis-pretreated(H)and unpretreated bamboo ***-pretreated(SHP)and unpretreated soda-anthraquinone(AQ)(SP)pulps were characterized by yield,Kappa number,alpha,beta,and gamma cellulose,degree of polymerization,water retention value,and *** nanocellulose was produced by a sequential chemical oxidation treatment(2,2,6,6-tetramethylpiperidine-1-oxyl,TEMPO reagent)and mechanical *** was characterized by carboxylic group content and *** results revealed that autohydrolysis pretreatment resulted in a higher hemicelluloses extraction in *** contrast,the pulping yield of unpretreated samples was higher for ***,and the soda-AQ pulps from this species exhibited better delignification than the autohydrolysis-pretreated *** crystallinity index values of the obtained pulps were high(>80%),and the alpha-cellulose contents were *** viscosities of the aqueous nanocellulose suspensions were higher for the nanocellulose solutions obtained from the unpretreated soda-AQ ***,nanocellulose from *** unpretreated soda-AQ pulps had a higher rate of carboxylic *** results of this work are significant in assessing the potential of both bamboo species as a source of high-value products within the biorefinery framework because the viscosities of the aqueous nanocellulose suspensions depend on the size and shape of *** has significant importance for industrial unit operations and potential applications.

关键词： Natural fiber Guadua angustifolia Guadua trinii soda-anthraquinone pulp nanocellulose

Boosting hydrogen and chemicals production through ethanol electro-reforming on Pt-transition metal anodes

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Journal of Energy chemistry 2022年第7期31卷 394-406,I0011页

作者： Alberto Rodríguez-Gómez fernando dorado Paula Sánchez Ana Raquel de la Osa chemical Engineering Department Faculty of Chemical Sciences and TechnologyUniversity of Castilla-La Mancha

The aim of this work is to boost the combined hydrogen and added-values compounds generation(acetaldehyde, acetic acid and ethyl acetate) through ethanol electrochemical reforming using bimetallic anodes. In particular, the influence of the secondary metal on the electrochemical performance as well as on the product distribution was studied. For that purpose, Pt X/c electrocatalysts(where X corresponds to cu, co, Ni and Ru) were synthesized by the modified polyol method and tested in both half-cell and proton exchange membrane(PEM) cell configurations. characterization results showed that incorporation of Ni and co into the Pt matrix enhances the morphological properties of the material, providing smaller crystallite sizes, higher active surface areas and hence, better dispersion when comparing to Ru and cu-based electrocatalysts. Ethanol oxidation reaction(EOR) was evaluated by cyclic, linear voltammetry and chronopotentiometry assays. Pt co/c and Pt Ni/c exhibited the highest electrocatalytic activity at high polarization levels, which translate into an improvement of more than 30%(up to 1050 m A cm^(-2)) in the hydrogen production and chemical yields. On the other hand, Pt Ru/c results more advantageous for a lower potential interval(cetic acid production despite sacrificing ethanol conversion. Pt cu/c presented the lowest results in both electrochemical performance and product distribution. Such differences in the electrochemical performance can be rationalized in terms of the synergistic effect between both metals(particle size distribution, grade of dispersion and hydrophilic behavior), which demonstrate that the incorporation of a different secondary metal plays an essential role in the EOR development.

关键词： Ethanol electrochemical reforming Bimetallic anodic electrocatalysts PEM cell High current performance Hydrogen chemicals production

Twenty years of population dynamics in European beech-oak forest at their rear range margin anticipate changes in its structure and composition

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Forest Ecosystems 2024年第3期11卷 358-370页

作者： álvaro Rubio-cuadrado Iciar Alberdi Isabel canellas fernando Montes Jesús Rodríguez-calcerrada Rosana López Guillermo G.Gordaliza María Valbuena-carabana Nikos Nanos Ramón Perea Luis Gil Departamento de dinamica y gestion forestal Instituto de Ciencias Forestales(ICIFOR-INIA)CSICCtra.La Coruna km 7.528040MadridSpain Departamento de Sistemas y Recursos Naturales Escuela Tecnica Superior de Ingeniería de MontesForestal y del Medio NaturalUniversidad Politecnica de Madrid.Ciudad Universitaria s/n28040MadridSpain School of Forestry and Natural Environment Aristotle University of ThessalonikiUniversity Campus54124ThessalonikiGreece

There is an increasing interest in restoring degraded forests,which occupy half of the forest *** the forms of restoration,passive restoration,which involves the elimination of degrading factors and the free evolution of natural dynamics by applying minimal or no management,is gaining *** dynamics is difficult to predict due to the influence of multiple interacting factors such as climatic and edaphic conditions,composition and abundance of species,and the successional character of these ***,we study the natural dynamics of a mixed forest located in central Spain,which maintained an open forest structure,due to intensive use,until grazing and cutting were banned in the *** most frequent woody species in this forest are Fagus sylvatica,Quercus petraea,Quercus pyrenaica,Ilex aquifolium,Sorbus aucuparia,Sorbus aria and Prunus avium,with contrasting shade and drought *** species are common in temperate European deciduous forest and are found here near their southern distribution limit,except for *** order to analyze forest dynamics and composition,three inventories were carried out in 1994,2005 and *** results show that,despite the Mediterranean influence,the natural dynamics of this forest has been mainly determined by different levels of shade *** the abandonment of grazing and cutting,*** expanded rapidly due to its lower shade tolerance,whereas after canopy closure and forest densification,shade-tolerant species gained ground,particularly ***,despite its lower drought and late-frost *** the current dynamics continue,*** will overtake the rest of the species,which will be relegated to sites with shallow soils and steep ***,all the multi-centennial beech trees,which are undergoing a rapid mortality and decline process,will disappear.

关键词： Forest succession Secondary forest Woodland Mixed forest competition Recruitment

Influence of Pt/Ru anodic ratio on the valorization of ethanol by PEM electrocatalytic reforming towards value-added products

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Journal of Energy chemistry 2021年第5期30卷 264-275页

作者： Alberto Rodriguez-Gomez fernando dorado Antonio de Lucas-consuegra Ana Raquel de la Osa chemical Engineering Department Faculty of Chemical Sciences and TechnologyUniversity of Castilla-La Mancha13071 Ciudad RealSpain

The ethanol electro-reforming process was studied over PtRu/c catalysts synthesized by the modified polyol method with different *** particular,this work reports the influence of anodic Pt:Ru ratio(5:1,2:1 and 1:2)on the organic product distribution(acetaldehyde,acetic acid and ethyl acetate)and pure hydrogen generation at different current densities operation *** characterization of the catalysts was made by X-ray diffraction(XRD),temperature-programmed reduction(TPR)and N_(2) adsorption-desorption *** patterns showed that Ru is introduced into the Pt structure,forming an alloy between both ***,the degree of alloy was higher by increasing the Ru *** TPR profiles Pt was found to be properly reduced while Ru was both in metallic state and forming *** electrochemical behaviour of each catalyst towards ethanol electroreforming process was investigated through electrochemical techniques in a half cell and a single proton exchange membrane(PEM)cell *** intermediate Pt:Ru ratio was found to result in high current density and electrochemical surface area(EcSA)values along with lower amounts of adsorbed ***,Ru addition seems to diminish the degree of degradation of the *** on characterization and in agreement with essays carried out in a PEM cell at mild conditions(80℃ and 1 atm),PtRu/c 2:1 anode provided the best electrocatalytic results in terms of current density(740 mA cm^(-2)),hydrogen production and selectivity toward acetic acid(up to 15%apart from acetaldehyde and ethyl acetate)while requiring the lowest energy consumption.

关键词： Ethanol electro-reforming PEM cell Pt:Ru anodic ratio Hydrogen production Value-added liquid product distribution