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Optimization of high-speed railway pantographs for improving pantograph-catenary contact

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Theoretical & Applied Mechanics Letters 2013年第1期3卷 51-57页

作者： Jorge Ambrósio Joo Pombo manuel pereira IDMEC-IST Technical Univ. of Lisbon Av. Rovisco Pais

A crucial system for the operation of high-speed trains is the pantograph catenary interface as it is the sole responsible to deliver electrical power to the train. Being the catenary a stationary system with a long lifespan it is also less likely to be redesigned and upgraded than the pantographs that fit the train vehicles. This letter proposes an optimization procedure for the improvement of the contact quality between the pantograph and the catenary solely based on the redesign of the pantograph head suspension characteristics. A pantograph model is defined and validated against experimental dynamic characteristics of existing pantographs. An optimization strategy based on the use of a global optimization method, to find the vicinity of the optimal solution, followed by the use of a deterministic optimization algorithm, to fine tune the optimal solution, is applied here. The spring stiffness, damping characteristics and bow mass are the design variables used for the pantograph optimization. The objective of the optimal problem is the minimization of the standard deviation of the contact force history, which is the most important quantity to define the contact quality. The pantograph head suspension characteristics are allowed to vary within technological realistic limits. It is found that current high-speed railway pantographs have a limited potential for mechanical improvements, not exceeding 10% 15% on the decrease of the standard deviation of the contact force. C 2013 The Chinese Society of Theoretical and Applied Mechanics. [doi：10.1063/2.1301306]

关键词： high-speed railway pantograph

What Do Cattle Prefer in a Tropical Climate： Water Immersion or Artificial Shade？

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Journal of Life Sciences 2012年第12期6卷 1356-1362页

作者： Ana Carina Alves pereira de Mira Geraldo Alfredo manuel Franco pereira Cristiane Gonqalves Titto Evaldo Antonio Lencioni Titto Animal Science and Food Engineering Faculty University of Sao Paulo Pirassununga 13635-900 Brazil Institute of Mediterranean Agricultural and Environmental Sciences University of Evora Evora 7000 Portugal

Animal performance is affected by high air temperature and it is known that shade reduces the absorption of radiant temperature, and water for immersion facilitates heat loss. This study intends to find preferences of resources that contribute for the well-being of cattle and how they alterdaily behaviour. During summer, six Caracu and six Red Angus bulls were submitted to two different treatments: availability of artificial shade and water for immersion and availability of water for immersion. The categories observed were: positions (in the sun, under the shade, in the water), posture (standing, lying down) and activities (grazing, ruminating, leisure). The behavioural patterns were recorded using the focal sampling method every 15 minutes (from 6:00 a. m. to 6:00 p. m.). When shade and water for immersion coexists, cattle in this study prefer shade to avoid solar radiation. Both breeds had remained more time grazing, followed by ruminating in the Caracu breed, and by resting in the Red Angus breed. The Caracu breed had presented clear preference for the shade resource, but that fact was not always observed in the Red Angus breed. In hot climates, resources for defence against heat load, as shade and water for immersion improve the well-being of cattle.

关键词：水浸泡公牛阴影热带气候人工辐射温度行为模式安格斯

Accounting and the ＂Doctor-Manager Relationship＂

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Journal of Modern Accounting and Auditing 2013年第4期9卷 489-496页

作者： Ame1ia Cristina Ferreira-da-Silva Jose manuel T. pereira Humberto Nuno Rito Ribeiro Polytechnic Institute of Porto Porto Portugal Jose Manuel T. Pereira Polytechnic Institute of Caivado and Ave Barcelos Portugal Polytechnic Institute of Braganca Braganga Portugal

Hepatic“pregnancy”:hepatocellular carcinoma with extensive extrahepatic growth

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Hepatobiliary Surgery and Nutrition 2023年第4期12卷 641-642页

作者： Ana Rita Ferreira Bárbara Castro Jose Daniel Martins João Varanda Alexandre Costa Bela pereira manuel Oliveira General Surgery Centro Hospitalar Vila Nova de Gaia/EspinhoVila Nova de GaiaPortugal

A female in her 50s,no previous personal history,presented to the Emergency Department with a 7 months history of progressively worsening abdominal diffuse pain associated with increasing abdominal *** physical examin... 详细信息

关键词： pregnancy Hepatic Figure

Synthesis and functionalization of carbon xerogels to be used as supports for fuel cell catalysts

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Journal of Energy Chemistry 2013年第2期22卷 195-201页

作者： Jos L. Figueiredo manuel F. R. pereira Laboratory of Catalysis and Materials Associate Laboratory LSRE/LCM Faculdade de Engenharia Universidade do Porto Rua Dr. Roberto Frias 4200-465 Porto Portugal

The synthesis and properties of carbon xerogels are briefly described in this mini-review, emphasizing the methods used for tuning their surface chemistry and textural properties in order to design efficient electrocatalysts for fuel cells. In particular, the role played by the surface functional groups in determining the loading, dispersion, oxidation state and stability of the metal phases is addressed.

关键词： carbon xerogels fuel cells electrocatalysts surface chemistry catalyst supports

Mannosylated glycans impair normal T-cell development by reprogramming commitment and repertoire diversity

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Cellular & Molecular Immunology 2023年第8期20卷 955-968页

作者： manuel M.Vicente Inês Alves Ângela Fernandes Ana M.Dias Beatriz Santos-pereira Elena Pérez-Anton Sofia Santos Tao Yang Alexandra Correia Anja Münster-Kühnel Afonso R.M.Almeida Sarina Ravens Gabriel A.Rabinovich manuel Vilanova Ana E.Sousa SaloméS.Pinho i3S–Institute for Research and Innovation in Health University of PortoPortoPortugal Institute of Biomedical Sciences Abel Salazar(ICBAS) University of PortoPortoPortugal Graduate Program in Areas of Basic and Applied Biology(GABBA) ICBASUniversity of PortoPortoPortugal Faculty of Medicine University of PortoPortoPortugal Nephrology Department Centro Hospitalar e Universitário do PortoPortoPortugal Institute of Immunology Hannover Medical SchoolHannoverGermany Institute of Clinical Biochemistry Hannover Medical SchoolHannoverGermany Instituto de Medicina Molecular João Lobo Antunes Faculdade de MedicinaUniversidade de LisboaLisboaPortugal Laboratorio de Inmunopatología Instituto de Biología y Medicina Experimental(IBYME)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Ciudad de Buenos AiresArgentina Laboratorio de Inmuno-oncología Translacional Instituto de Biología y Medicina Experimental(IBYME)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Ciudad de Buenos AiresArgentina Facultad de Ciencias Exactas y Naturales(FCEyN) Universidad de Buenos AiresCiudad de Buenos AiresArgentina

T-cell development ensures the formation of diverse repertoires of T-cell receptors(TCRs)that recognize a variety of *** is a major posttranslational modification present in virtually all cells,including T-lymphocytes,that regulates activity/*** these structures are known to be involved in TCR-selection in DP thymocytes,it is unclear how glycans regulate other thymic development processes and how they influence susceptibility to ***,we discovered stage-specific glycome compositions during T-cell development in human and murine thymocytes,as well as dynamic *** restricting the N-glycosylation profile of thymocytes to high-mannose structures,using specific glycoengineered mice(Rag1CreMgat1fl/fl),we showed remarkable defects in key developmental checkpoints,includingß-selection,regulatory T-cell generation andγδT-cell development,associated with increased susceptibility to colon and kidney inflammation and *** further demonstrated that a single N-glycan antenna(modeled in Rag1CreMgat2fl/fl mice)is the sine-qua-non condition to ensure normal *** conclusion,we revealed that mannosylated thymocytes lead to a dysregulation in T-cell development that is associated with inflammation susceptibility.

关键词： N-glycosylation T-cell development Thymocytes Glycocalyx Inflammation

Effect of climate and altitude on plant community composition and richness in Brazilian inselbergs

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Journal of Mountain Science 2020年第8期17卷 1931-1941页

作者： Herval Vieira PINTO-JUNIOR Pedro manuel VILLA Luis Fernando Tavares de MENEZES Miriam Cristina Alvarez pereira Universidade Federal de Vigosa Department of Plant BiologyLaboratory of Ecology and Evolution of Plants36570-900Vicosa-MGBrazil Universidade Federal de Vigosa Department of Forest EngineeringLaboratory of Forest Restoration36570-900Vicosa-MGBrazil Universidade Federal do Espirito Santo Department of Agrarian and Biological SciencesLaboratory of Ecology of Restinga and Mata Atlantica29932-900Sao Mateus-ESBrazil Universidade Federal do Espirito Santo Department of Biology29500-000Alegre-ESBrazil

Plant communities are shaped by multiple factors along environmental gradients;however,studies are limited on how environmental filtering drives community composition and species richness on tropical *** evaluate the influence of altitude and climatic variables related to temperature and precipitation on plant community composition and species richness on Brazilian *** assume as a premise that both climate and altitude would induce changes on plant community composition and species richness at the local *** used plant inventory data from 370 sampling units across four inselberg sites in the Atlantic Forest of Espírito Santo State,south-eastern *** tested the univariate and multivariate effects of altitude and climate variables on community composition and species richness with multiple *** in species richness between inselbergs were evaluated using sample-based data to estimate rarefaction and extrapolation *** addition,differences in species composition and taxonomic beta diversity were examined via novel frequency-based metrics.A contrasting climate pattern was observed between the inselberg sites,with south sites being wet compared to the dry conditions found in northern *** richness by rarefaction showed a similar pattern within regional sites;however,there were marked differences between *** richness and beta diversity showed significant differences among sites,with higher values in southern sites than in northern *** a multi-model comparison between inselberg sites,altitude significantly influenced community composition and species richness and explained more variance than climate *** finding suggested that climate could act to some extent on these tropical inselbergs;however,altitude was a better predictor of plant community composition and species richness at the local level.

关键词： Atlantic Forest Biome Beta diversity Abiotic filtering Climate models Environmental filtering Latitudinal gradient

Optimization of an innovative approach involving mechanical activation and acid digestion for the extraction of lithium from lepidolite

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International Journal of Minerals,Metallurgy and Materials 2018年第1期25卷 11-19页

作者： Nathalia Vieceli Carlos A.Nogueira manuel F.C.pereira Fernando O.Durao Carlos Guimaraes Fernanda Margarido Center for Innovation Technology and Po icy Research-IN+Instituto Superior T6cnicoUniversity of Lisbon1049-001 LisboaPortugal LNEG-Laborat6rio Nacional de Energia e Geologia I.P.Campus do Lumiar1649-038 LisboaPortugal CERENA-Centro de Recursos Naturais e Ambiente DECivilInstituto Superior T6cnicoUniversity of Lisbon1049-001 LisboaPortugal

The recovery of lithium from hard rock minerals has received increased attention given the high demand for this element. There- fore, this study optimized an innovative process, which does not require a high-temperature calcination step, for lithium extraction from le- pidolite. Mechanical activation and acid digestion were suggested as crucial process parameters, and experimental design and re- sponse-surface methodology were applied to model and optimize the proposed lithium extraction process. The promoting effect of amorphi- zation and the formation of lithium sulfate hydrate on lithium extraction yield were assessed. Several factor combinations led to extraction yields that exceeded 90%, indicating that the proposed process is an effective approach for lithium recovery.

关键词： lepidolite lithium mechanical activation acid digestion optimization extraction

The effect of fatigue and duration knowledge of exercise on kicking performance in soccer players

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Journal of Sport and Health Science 2019年第6期8卷 567-573页

作者： Ricardo manuel Pires Ferraz Roland van den Tillaar Ana pereira Mario C.Marques Department of Sports Sciences University of Beira InteriorCovilha 6201-001Portugal Research Center in Sports Sciences Health and Human DevelopmentCIDESDVila Real 5000-801Portugal Department of Teacher Education of Nord University Levanger 7600Norway Department of Technology and Science School of Education of Polytechnic Institute of SetubalSetubal 2910-761Portugal

Purpose:The purpose of this study was to investigate the influence of fatigue upon kicking maximal ball velocity and the target-hitting accuracy of soccer players;and also to examine the effect of the knowledge of the exercise duration upon these 2 ***:Twenty-four semi-professional soccer players participated in this study and performed maximal instep kicks before and after the implementation of an exercise protocol,either with or without knowledge of the duration of this ***:A mixed model of analysis of variance showed that kicking maximal ball velocity was significantly affected(F(5,85)=11.6,p<0.001,η^2=0.39) but only after just 1 circuit of the fatigue protocol and then remained *** did not change during the protocol(F(5,75)=0.23,p=0.76,η^2=0.03) and knowing the duration of exercitation did not affect accuracy and velocity development(F(1,23) ≤1.04,p≥0.32,η~2≤0.06).Conclusion:These findings demonstrated the potential negative effects of fatigue on kicking ball velocity in soccer but not in the kicking accuracy and that the effect of fatigue may not be progressive over *** or not knowing the duration of exercitation did not affect the results.

关键词： Fatigue Kicking ball velocity Pacing Perception of effort Self-regulation of effort