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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 carre?o c.m.cepeda-jiménez Alberto Orozco-caballero Physical metallurgy Department CENIM-CSIC Department of mechanical Engineering Chemistry and Industrial Design Polytechnic University of Madrid

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 3 μm） prone to extensive superplastic response. The three friction stir processed samples clearly deformed by grain boundary sliding（GBS） deformation mechanism at high temperatures. The maximum elongations to failure, well over 400% at high strain rate of 10-2s-1, were reached at 400 ℃ in the material with coarsest grain size of 2.8 μm, and at 300 ℃ for the finest grain size of 2 μm. Nevertheless, 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 temperatures. This 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

The relation between ductility at high temperature and solid solution in mg alloys

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Journal of magnesium and Alloys 2022年第1期10卷 241-256页

作者： D.F.Shi c.m.cepeda-jiménez m.T.Pérez-Prado Im DEA materials Institute C/Eric Ka ridel228906 GetafeMadridSpain Department of materials Science Polytechnic University of Madrid/Universidad Politecnica de MadridE.T.S.de Ingenieros de Caminos28040MadridSpain Department of Physical metallurgy CENIMCSICAv.Gregorio del Amo 828040 MadridSpain

This work investigates the effect of solid solution on ductility and on the activation of individual deformation mechanisms at moderate temperatures and at quasi-static strain rates in mg-Zn and mg-Al alloys. With that aim, four solid solution mg-Zn and mg-Al binary alloy ingots containing 1 and 2 wt.% solute atoms were subjected to hot rolling and subsequent annealing to generate polycrystals with similar average grain size and basal-type texture for each composition. The activity of the different slip systems after tensile testing at 150°c and at 250°c was evaluated in pure mg and in the alloys by EBSD-assisted slip trace analysis. In addition, segregation of Zn and Al atoms at grain boundaries during the thermo-mechanical processing was characterized by HAADF-STEm and EDX. It was found that while the addition of Al and Zn atoms to pure mg does not lead to major changes in the mechanical strength at the investigated temperatures, it does enhance ductility significantly, especially at 250℃. Our results show that this increase in ductility cannot be attributed to a higher activation of non-basal systems in the alloys, as reported earlier, as the incidence of non-basal systems is indeed considerably higher in pure mg. This work suggests, on the contrary, that the ductility increase may be attributed to the presence of a more homogenous basal activity in the alloys due to a lower degree of orientation clustering, to grain boundary solute segregation, and to a higher slip diffusivity at grain interiors.

关键词： magnesium Solute segregation Slip trace analysis Ductility Deformation mechanisms

Single atom cu-N-c catalysts for the electro-reduction of cO_(2) to cO assessed by rotating ring-disc electrode

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Journal of Energy chemistry 2024年第1期88卷 169-182,I0004页

作者： S.Pérez-Rodríguez m.Gutiérrez-Roa c.Giménez-Rubio D.Ríos-Ruiz P.Arévalo-cid m.V.martínez-Huerta A.Zitolo m.J.Lázaro D.Sebastián Instituto de carboquímica(cSIc) Miguel Luesma Castán 450018 ZaragozaSpain Instituto de catálisis y Petroleoquímica(cSIc) Marie Curie 228049 MadridSpain Synchrotron SOLEIL L’Orme des MerisiersDépartementale 12891190France

The electrochemical cO_(2) reduction reaction(cO_(2)RR) to controllable chemicals is considered as a promising pathway to store intermittent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped carbon xerogel(cu-N-c) are successfully developed varying the copper amount and the nature of the copper precursor, for the efficient cO_(2)RR. The electrocatalytic performance of cu-N-c materials is assessed by a rotating ring-disc electrode(RRDE), technique still rarely explored for cO_(2)RR. For comparison, products are also characterized by online gas chromatography in a H-cell. The as-synthesized cu-Nc catalysts are found to be active and highly cO selective at low overpotentials(from -0.6 to -0.8 V vs.RHE) in 0.1 m KHcO_(3), while H_(2) from the competitive water reduction appears at larger overpotentials(-0.9 V vs. RHE). The optimum copper acetate-derived catalyst containing cu-N_(4) moieties exhibits a cO_(2)-to-cO turnover frequency of 997 h^(-1) at -0.9 V vs. RHE with a H_(2)/cO ratio of 1.8. These results demonstrate that RRDE configuration can be used as a feasible approach for identifying electrolysis products from cO_(2)RR.

关键词： cu-N-c carbon xerogel Rotating ring disc electrode carbon dioxide reduction reaction carbon monoxide

multichannel coupling induced topological insulating phases with full multimerization

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Photonics Research 2024年第3期12卷 491-498页

作者： JUN LI YAPING YANG c-m.HU mOE Key Laboratory of Advanced micro-Structured materials School of Physics Science and EngineeringTongji UniversityShanghai 200092China Department of Physics and Astronomy University of ManitobaWinnipegManitoba R3T 2N2Canada

We propose and experimentally realize a class of quasi-one-dimensional topological lattices whose unit cells are constructed by coupled multiple identical resonators,with uniform hopping and inversion symmetry.In the presence of coupling-path-induced effective zero hopping within the unit cells,the systems are characterized by complete multimerization with degenerate-1 energy edge states for open boundary condition.

关键词： symmetry topological coupling

Photosynthetic Gas Exchange and Nitrogen Assimilation in Green Bean Plants Supplied with Two Sources of Silicon

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Phyton-International Journal of Experimental Botany 2024年第5期93卷 963-980页

作者： Julio c.Anchondo-Páez Esteban Sánchez carlos A.Ramírez-Estrada Alondra Salcido-martínez Erick H.Ochoa-chaparro Department of Plant Physiology Centro de Investigación en Alimentación y DesarrolloCiudad Delicias33089México

Beans contain a wide range of vitamins,proteins,calcium,and zinc which make them an important food source for many countries.To meet the demand for bean production worldwide,large amounts of fertilizers and pesticides are used.However,the cost of production and environmental impact increases.To produce food sustainably,the use of beneficial nutrients such as silicon as a biostimulant has been proposed.However,information about the effect of different sources of silicon on the metabolism of bean plants is scarce.Bean plants cv.Strike were grown in pots for 60 days and the effect of foliar application of silicon nanoparticles and the silicon-based biostimulant codasilat 4 concentrations(0,1,2,and 4 mm)on total biomass,yield,photosynthetic pigment concentration,photosynthetic activity,stomatal conductance,transpiration rate,chlorophyll fluorescence,and nitrogen assimilation were evaluated.The results obtained showed that the supply of silicon at a dose of 1 mm functioned as a biostimulant,favoring gas exchange and nitrogen assimilation within the plant,which stimulated growth and yield.The results of this research work allowed a better comprehension of the effects of silicon application through silicon nanoparticles and the biostimulant codasilon the physiology of green bean plants.

关键词： Nanoparticles silicon Phaseolus vulgaris L.

Dietary(poly)phenol intake is associated with cardiometabolic health parameters in adolescents

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Food Science and Human Wellness 2024年

作者： Emily P.Laveriano-Santos Sara castro-Barquero camila Arancibia-Riveros Ana maría Ruiz-León Rosa casas Ramón Estruch Patricia Bodega mercedes de miguel Amaya de cos-Gandoy Jesús martínez-Gómez Gloria Santos-Beneit Juan m.Fernández-Alvira Rodrigo Fernández-jiménez Rosa m.Lamuela-Raventós Anna Tresserra-Rimbau The Zena and michael A.Wiener cardiovascular Institute Icahn School of medicine at mount Sinai Department de Nutrició ciències de l'Alimentació I Gastronomia XIA Facultat de Farmàcia i ciències de l'alimentació Institut de Recerca en Nutrició i Seguretat Alimentària (INSA-UB) Universitat de Barcelona Department of Internal medicine Hospital clínic Institutd'Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS) University of Barcelona consorcio cIBER m.P.Fisiopatología de la Obesidad y Nutrición (cIBERObn) Instituto de Salud carlos III (IScIII) mediterranean Diet Foundation 5. Foundation for Science Health and Education (SHE) 6. centro Nacional de Investigaciones cardiovasculares (cNIc) cIBER de Enfermedades cardiovasculares (cIBERcV) 9. Hospital Universitario clínico San carlos

Background: The protective role of (poly)phenols against metabolic disorders has been extensively studied in adults but not in adolescents.Objective: To assess associations of dietary (poly)phenols and their subclasses with cardiometabolic health parameters in adolescents. methods: A cross-sectional study was conducted in 944 individuals aged 11 to 14 years enrolled in the SI! Program for Secondary Schools trial (NcT03504059). (Poly)phenol intake was assessed using semi-quantitative food frequency questionnaires and the Phenol-Explorer database. The measured cardiometabolic parameters were waist circumference (Wc) age-sex z-score， blood pressure (BP) age-sex z-score， blood glucose (BG)， triglycerides (TG)， and high-density lipoprotein cholesterol (HDL-c). multilevel mixed-effect linear regression models were applied to examine the association between (poly)phenol quintiles and cardiometabolic health parameters.Results: compared to the lowest quintile， adolescents in the highest quintile of total (poly)phenol intake had lower Wc z-scores (β=-0.09， 95%cI=-0.09;-0.08， P-for trend=0.002)， mean arterial pressure z-scores (β =-0.11， 95%cI=-0.12;-0.09， P-for trend=0.206)， and HDL-c (β=-1.52， 95%cI=-2.90;-0.14， P-for trend=0.108)， after multivariable adjustment. The Wc z-scores (β=-0.11， 95%cI=-0.19;-0.03， P-for trend=0.013) and HDL-c (β=-2.16， 95%cI=-3.78;-0.53， P-for trend=0.046) were lower in the highest quintile of flavonoid intake compared to the lowest quintile. The highest quintile of phenolic acid intake was associated with a lower Wc z-score (β=-0.14， 95%cI=-0.26;-0.02， P-for trend=0.011) and TG levels (β=-8.83， 95%cI=-12.37;-5.30， P-for trend cI= -3.103;-0.64， P-for trend cI= -4.95;-1.49， P-for trend=0.034)， and with higher HDL-c (β=2.328， 95%cI= 1.40;3.17， P-for trend=0.466) compared to the lowest quintile. conclusion: A higher intake of (poly)phenols， especially flavonoids， phenolic acids， and stilbenes

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The influence of resistance exercise training prescription variables on skeletal muscle mass,strength,and physical function in healthy adults:An umbrella review

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Journal of Sport and Health Science 2024年第1期13卷 47-60页

作者： Jonathan c.mcleod Brad S.currier caroline V.Lowisz Stuart m.Phillips Department of Kinesiology Faculty of ScienceMcMaster UniversityHamilton L8S4L8Canada

Purpose:The aim of this umbrella review was to determine the impact of resistance training(RT)and individual RT prescription variables on muscle mass,strength,and physical function in healthy adults.methods:Following Preferred Reporting Items for Systematic Reviews and meta-Analyses(PRISmA)guidelines,we systematically searched and screened eligible systematic reviews reporting the effects of differing RT prescription variables on muscle mass(or its proxies),strength,and/or physical function in healthy adults aged>18 years.Results:We identified 44 systematic reviews that met our inclusion criteria.The methodological quality of these reviews was assessed using A measurement Tool to Assess Systematic Reviews;standardized effectiveness statements were generated.We found that RT was consistently a potent stimulus for increasing skeletal muscle mass(4/4 reviews provide some or sufficient evidence),strength(4/6 reviews provided some or sufficient evidence),and physical function(1/1 review provided some evidence).RT load(6/8 reviews provided some or sufficient evidence),weekly frequency(2/4 reviews provided some or sufficient evidence),volume(3/7 reviews provided some or sufficient evidence),and exercise order(1/1 review provided some evidence)impacted RT-induced increases in muscular strength.We discovered that 2/3 reviews provided some or sufficient evidence that RT volume and contraction velocity influenced skeletal muscle mass,while 4/7 reviews provided insufficient evidence in favor of RT load impacting skeletal muscle mass.There was insufficient evidence to conclude that time of day,periodization,inter-set rest,set configuration,set end point,contraction velocity/time under tension,or exercise order(only pertaining to hypertrophy)influenced skeletal muscle adaptations.A paucity of data limited insights into the impact of RT prescription variables on physical function.conclusion:Overall,RT increased muscle mass,strength,and physical function compared to no exercise.RT intensity(load)and weekly frequency impacted RT-

关键词： Hypertrophy Resistance training Resistance training prescription variables Strength Umbrella review

Semi-analytical investigation of heat transfer in a porous convective radiative moving longitudinal fin exposed to magnetic field in the presence of a shape-dependent trihybrid nanofluid

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Applied mathematics and mechanics(English Edition) 2024年第1期45卷 197-216页

作者： c.G.PAVITHRA B.J.GIREESHA m.L.KEERTHI Department of PG Studies and Research in mathematics Kuvempu UniversityShankaraghatta 577451India Department of mathematics and Statistics M.S.Ramaiah University of Applied SciencesBengaluru 560058India

The thermal examination of a non-integer-ordered mobile fin with a magnetism in the presence of a trihybrid nanofluid(Fe_3O_4-Au-Zn-blood) is carried out. Three types of nanoparticles, each having a different shape, are considered. These shapes include spherical(Fe_3O_4), cylindrical(Au), and platelet(Zn) configurations. The combination approach is utilized to evaluate the physical and thermal characteristics of the trihybrid and hybrid nanofluids, excluding the thermal conductivity and dynamic viscosity. These two properties are inferred by means of the interpolation method based on the volume fraction of nanoparticles. The governing equation is transformed into a dimensionless form, and the Adomian decomposition Sumudu transform method(ADSTm) is adopted to solve the conundrum of a moving fin immersed in a trihybrid nanofluid. The obtained results agree well with those numerical simulation results, indicating that this research is reliable. The influence of diverse factors on the thermal overview for varying noninteger values of γ is analyzed and presented in graphical representations. Furthermore, the fluctuations in the heat transfer concerning the pertinent parameters are studied. The results show that the heat flux in the presence of the combination of spherical, cylindrical, and platelet nanoparticles is higher than that in the presence of the combination of only spherical and cylindrical nanoparticles. The temperature at the fin tip increases by 0.705 759% when the value of the Peclet number increases by 400%, while decreases by 11.825 13% when the value of the Hartman number increases by 400%.

关键词： convection radiation moving longitudinal fin Adomian decomposition Sumudu transform method(ADSTm) trihybrid nanofluid magnetic field

cannabinoids and endocannabinoids as therapeutics for nervous system disorders:preclinical models and clinical studies

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Neural Regeneration Research 2024年第4期19卷 788-799页

作者： R.Scott Duncan Sean m.Riordan matthew c.Gernon Peter Koulen Department of Ophthalmology School of MedicineUniversity of Missouri Department of Biomedical Sciences School of MedicineUniversity of Missouri

cannabinoids are lipophilic substances derived from cannabis sativa that can exert a variety of effects in the human body.They have been studied in cellular and animal models as well as in human clinical trials for their therapeutic benefits in several human diseases.Some of these include central nervous system(cNS)diseases and dysfunctions such as forms of epilepsy,multiple sclerosis,Parkinson’s disease,pain and neuropsychiatric disorders.In addition,the endogenously produced cannabinoid lipids,endocannabinoids,are critical for normal cNS function,and if controlled or modified,may represent an additional therapeutic avenue for cNS diseases.This review discusses in vitro cellular,ex vivo tissue and in vivo animal model studies on cannabinoids and their utility as therapeutics in multiple cNS pathologies.In addition,the review provides an overview on the use of cannabinoids in human clinical trials for a variety of cNS diseases.cannabinoids and endocannabinoids hold promise for use as disease modifiers and therapeutic agents for the prevention or treatment of neurodegenerative diseases and neurological disorders.

关键词： anandamide cannabidiol cannabinoid endocannabinoid epilepsy multiple sclerosis neurodegeneration neuroprotection tetrahydrocannabinol

Foraging valor linked with aggression:selection against completely abandoning aggression in the high-elevation ant Tetramorium alpestre?

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Insect Science 2024年第3期31卷 953-970页

作者： marie-Luise contala Patrick Krapf Florian m.Steiner Birgit c.Schlick-Steiner molecular Ecology Group Department of EcologyUniversitat InnsbruckInnsbruckAustria rganismal&Evolutionary Biology Research Programme University of HelsinkiHelsinkiFinland

Aggression has multiple benefits and is often coupled with other behaviors("behavioral syndromes").The level of aggressiveness is influenced by an adaptive benefit-cost ratio suggesting that benefits should outweigh the costs of aggression.Here,we assess if several behaviors are coupled in two behaviorally different populations(aggressive,peaceful)of the high-elevation ant Tetramorium alpestre.For three weeks,we collected colony fragments and analyzed boldness,exploring,foraging,and risk-taking behaviors.We hypothesized that the aggressive population is bolder,more explorative and risk-prone,and forages more food than the peaceful population.To test whether(a)the combination of experiments and parameters used yields a good setup,(b)populations differ behaviorally,and(c)populations display behavioral syndromes,we assessed(a)the frequency of repeatable behaviors of each experiment,(b)the behavioral means among populations,and(c)the behavioral repeatability,respectively.We found that(a)boldness and exploring were most repeatable and represent a good experimental setup,(b)the aggressive population was bolder and more explorative and risk-prone than the peaceful population,(c)boldness and exploring behaviors were highly repeatable in both populations,thus corroborating our hypothesis.The results suggest that boldness,exploring,and risk-taking but not foraging are presumably coupled with aggression and indicate the presence of behavioral syndromes in this ant.Under specific ecological conditions,aggression may be coupled with other behaviors and important for finding food.Aggression is probably adaptive in T.alpestre,possibly indicating that selection favors aggression at least partially,which may counteract the complete loss of intraspecific aggression.

关键词： adaptive value behavioral syndromes boldness exploration repeatability trade-off