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Failure of Semi-infinite Beams of Variable Thickness and Curvature on Elastic Foundation under Contact Loading

Journal of Civil Engineering and Architecture 2013年第2期7卷 174-184页

作者： joao batista de aguiar Jose Manoel de aguiar department of Engenharia AeroEspaeial Universidade Federal do ABC Santo Andre 09210-170 Brazil department of Ensino Geral Faculdade de Teenologia de Sao Paulo Sao Paulo 01124-060 Brazil

In early winter it is usual, in cold regions, that ice features approach offshore structures, like offshore platforms, impacting them, in a slow process of constant deformation build up. Interaction follows, in many cases, up to the point where ice-failure caused by bending fracture takes place. This supposes very large contact forces that the structure has to resist. Therefore, quantification of these efforts is of vital importance to the structural design of platforms. In several designs, these platforms are constructed with inclined walls so as to cause ice to fail in a flex-compression mode. In such a case the ice feature is analyzed as a beam constituted of a linear elastic material in brittle state with constant ice thickness. The simplification renders the problem solvable in a close form. However, this hypothesis goes against field observations. Marine currents action, wind and the sequence of contacts among features lead to thickness variations. Here this factor is addressed in the construction of a model, for harmonic forms of variation of thickness profile, and the accompanying curvature variations, whose solution determines field variables used to address the failure question. Due to the deformation dependency of the loading, a numerical scheme for the two-point boundary value problem in the semi-infinite space is developed. Failure pressures are computed based on a Rankine locus of failure. Variations of the order of 20% in the failure loads, as compared to the uniform beam model, are observed.

关键词： Ice beams thickness variation elastic behavior frictional contact bending failure loads.

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The effect of salinity on Fucus ceranoides (Ochrophyta,Phaeophyceae) in the Mondego River(Portugal)

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Journal of Oceanology and Limnology 2019年第3期37卷 881-891页

作者： COTAS joao FIGUEIRINHA Artur PEREIRA Leonel batista Teresa department of Life Sciences University of CoimbraCoimbra 3001-456Portugal MARE-Marine and Environmental Sciences Centre Faculty of Science and TechnologyUniversity of CoimbraCoimbra 3000-548Portugal Laboratory of Pharmacognosy Faculty of PharmacyUniversity of CoimbraCoimbra 3000-548Portugal LAQV REQUIMTEFaculty of PharmacyUniversity of CoimbraCoimbra 3000-548Portugal CIEPQPF Department of Chemical EngineeringFaculty of Science and TechnologyUniversity of CoimbraCoimbra 3030-790Portugal

Algae(and their extracts)are increasingly important for pharmaceutical applications due to the diversity of useful compounds they *** genus Fucus contains one of the most studied species,Fucus *** species *** differs from the others of the genus by presenting longitudinal air-vesicles and a capacity to survive at low *** is an alga that inhabits the Mondego River estuary(Portugal),at the southern limit of its distribution,and can serve as a role model to understand the effect of a salt gradient on the production of bioactive *** assessed the phenolic content and antioxidant activity of different *** extracts(***,aqueous and polysaccharide)prepared from samples harvested from two different zones to evaluate if the adaptation of *** to different salinity levels influenced its chemical *** antioxidant activity of the extracts was determined using 1,2-diphenyl-picrylhydrazyl(DPPH)and 2.2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS)*** assays demonstrated that the methanolic extract of lyophilized *** that grew at low salinities was the most bioactive,***(IC 50=50.39μg/mL)and ABTS(TEAC=2.42).The total phenolic content(Folin-Ciocalteu method)and the methanolic extract of the lyophilized *** collected from a low salinity habitat exhibited the highest phenolic content(PGE=49.48μg/mg of lyophilized extract)amongst those *** layer chromatography(TLC)and Fourier transform infrared spectroscopy(FTIR)were used for the identification of compounds in the *** characterization allowed confirmation that the various extracts contained almost the same compounds but with notable quantitative *** on these results,we conclude that there were differences in the quantity of the compounds due to the effect of *** drying methods used were also found to have influenced the quality of the extracted compounds.

关键词： Fucus ceranoides salinity gradient sequential extractions phenolic content dependent bioactivities spectroscopic analysis

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The growth and production modeling of individual trees of Eucalyptus urophylla plantations

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Journal of Forestry Research 2020年第5期31卷 1663-1672页

作者： joao Victor Nobre Carrijo Ana Beatriz de Freitas Ferreira Marcela Costa Ferreira Mario Cesar de aguiar Eder Pereira Miguel Eraldo Aparecido Trondoli Matricardi Alba Valeria Rezende department of Forestry Faculty of TechnologyUniversity of Brası´liaBrası´lia 70910-900Brazil

Individual tree models(ITMs)are classified as growth and production models for projecting current and future forest *** are more complex than other growth and production models,show a higher level of detail and,consequently,produce a better modeling ***,the accuracy and efficiency of ITMs have not been properly assessed to *** this study,we estimated the growth in height,diameter,and individual tree volume of a Eucalyptus urophylla plantation by applying an *** used a continuing forest inventory dataset in which 1554 individual trees within 29 permanent plots were measured in the field over a 6-year period(24 to 72 months).Each individual tree volume was estimated for future tree *** achieve this,we adjusted the model to predict the height and diameter growth,and the probability of mortality as a function of the competition *** ITM accuracy was assessed based on the analysis of variance results and,subsequently,the multiple mean comparison test at the 5%significance *** tree volumes predicted by the ITM for the forest stand aged 72 months,beginning at ages 24,36,48,and 60 months,were compared to the field measured tree volume acquired from the 72-month forest inventory that was used as the reference *** and observed tree volumes were similar when the estimation was based on the 48-month forest *** results might help to reduce financial costs of forest inventory because the ITM produces accurate future predictions of forest stand *** estimated ITM for Eucalyptus plantations using measurement intervals up to 2 years is recommended because it significantly reduced the projected volume discrepancy compared to the field measurements.

关键词： Competition index Forest production Forest site Simulation models Tree mortality

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The Importance of the Three-Dimensional Image in the Early Diagnosis of Cementoblastoma

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Open Journal of Radiology 2012年第1期2卷 10-13页

作者： Tania Mara Pimenta Amaral Claudia Silami de Magalhaes Allyson Nogueira Ricardo Alves Mesquita joao batista de Freitas Maria Cassia Ferreira aguiar department of Oral Pathology and Surgery School of Dentistry Universidade Federal de Minas Gerais Belo Horizonte Brazil department of Restorative dentistry School of Dentistry Universidade Federal de Minas Gerais Belo Horizonte Brazil

The cementoblastoma is a very rare odontogenic neoplasm characterised by the formation of cementum-like tissue in connection with the root of a tooth. An 18-year-old boy was referred to the Clinic of Oral Pathology of the School of dentistry, Universidade Federal de Minas Gerais, Brazil, complaining of an irradiating, itching pain from the region of the lower right first molar. He reported that the symptoms began three months prior, with a gradual increase in intensity during this period. The pain episodes were of short duration, with characteristics of toothache originating from the pulp. Upon intra-oral clinical examination, an open bite and slight increase in volume at the buccal alveolar region of the lower right first molar was observed. He also reported palpation and percussion pain symptoms in this region. Electrical, heat and cold pulp vitality tests were performed, and the tooth was vital. Periapical and panoramic radiographs showed radiolucent images with diffuse, poorly defined borders at the mesial root periapex extending to the interradicular region suggesting an inflammatory periapical lesion. In this early presentation, the three-dimensional image was fundamental to the final diagnosis of cementoblastoma.

关键词： Cementoblastoma Cone Beam CT dental Radiography

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Phytosociological Survey of Weeds in Areas of Crop-Livestock Integration

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American Journal of Plant Sciences 2014年第8期5卷 1090-1097页

作者： Karina batista Alessandra Aparecida Giacomini Luciana Gerdes Waldssimiler Teixeira de Mattos joao batista de Andrade Instituto de Zootecnia Agência Paulista de Tecnologia dos Agronegócios Nova Odessa Brazil

The dynamics of the weeds in the areas of crop-livestock integration is constantly changing depending on the various uses of the area. This study identified and quantified the floristic composition of weeds in areas of integration of maize for silage with Urochloa ruziziensis cv. Common at different densities of grass (0, 4 and 10 kg·ha-1) to grazing of beef cattle. The experimental design was completely randomized. A square of side0.5 m(0.25 m2area) was launched 24 times in each study area. The survey was conducted at the grain filling stage of maize. The specie contained in each frame were identified and counted. The phytosociological survey identified 9 families of weeds in areas assessed, with 7 families in every area of integrated cultivation maize with Urochloa ruziziensis at densities of 10 kg·ha-1 and 4 kg·ha-1 and 8 families in the area of maize cultivated alone. The Asteraceae family was the most represented in number of species. Sida spp (Malvaceae) showed greater potential to cause damage to maize. Urochloa ruziziensis at planting density of 10 kg·ha-1 provided greater competition with weeds in the integration with maize.

关键词： Asteraceae Crop-Livestock System Forage Silage Weed Species

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Intellectual capital and value creation in the production and assembly of vehicles and auto-parts sector in Brazil： A panel data analysis

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Journal of Modern Accounting and Auditing 2010年第8期6卷 15-25页

作者： Leonardo Fernando Cruz Basso Herbert Kimura joao Francisco de aguiar Mackenzie Presbyterian University S6o Paulo 01302-907 Brasil

This work investigates the relationship between intellectual capital and value creation in the sector of production and assembly of vehicles and auto-parts in Brazil. Through the access of the database from the annual industrial research conducted by the Brazilian Institute of Geography and Statistics, we gathered 865 observations, from 2000 to 2006, of public and private Brazilian companies with more than 100 employees. The database allows the estimate of relevant aggregated variables such as national accounts, gross domestic product, intermediate consumption, as well as propitiates a sectorial study of business strategies and performance, including value added by individual companies. In particular, in this study we use data on variables associated to intellectual capital. To achieve the goal of the study, we consider intellectual capital as defined by Pulic （2000, 2002）, including human capital and structural capital. For the analysis of business performance, we used Pulic＇s VAIC （Value Added Intellectual Cofficient） index as a measure of efficiency of the employed financial and intellectual capital. Regression models were run to verify the relationship among the efficiency in the use of intellectual capital and the profitability of Brazilian companies. The gross income, calculated as before selling, general and administrative expenses, depreciation expenses, amortization and interest expenses, was used as measure of the flows of value creation and the profitability was measured by the gross income to the total assets of the companies. Considering the constructs defined by Pulic （2000, 2002）, we tested, for the Brazilian sector of Production and Assembly of Vehicles and Auto-parts, the following hypotheses：（l） there is a positive relationship between value creation and intellectual capital, （2） there is a positive relationship between value creation and stock of intellectual capital, （3） there is a positive relationship between value creation and efficiency of t

关键词： intellectual capital value creation panel data analysis production and assembly of vehicles andauto-parts sector in Brazil

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Effects of laser surface melting on crystallographic texture, microstructure, elastic modulus and hardness of Ti-30Nb-4Sn alloy

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Transactions of Nonferrous Metals Society of China 2020年第2期30卷 392-404页

作者： Leonardo FANTON Nelson batista de LIMA Emilio Rayon ENCINAS Vicente Amigo BORRAS Conrado Ramos Moreira AFONSO joao batista FOGAGNOLO School of Mechanical Engineering University of CampinasRua Mendeleyev200CEP 13083-860CampinasSPBrazil Instituto de Pesquisas Energéticas e Nucleares Av.Prof.Lineu Prestes2242CEP 05508-000São PauloSPBrazil Institut de Tecnologia de Materials Universitat Politècnica de ValènciaCamino de Veras/nCódigo Postal 46022ValenciaSpain department of Materials Engineering Federal University of São CarlosRodovia Washington LuísKm 235CEP 13565-905São CarlosSPBrazil

The biocompatibility of orthopedic implants is closely related to their elastic modulus and surface *** objective of this study was to determine the effects of cold rolling,recrystallization and laser surface melting(LSM)on the microstructure and mechanical properties of a biphase(α″+β)Ti-30Nb-4Sn alloy.X-ray diffraction(XRD)texture analysis of the cold-rolled substrate revealed the[302]α″//ND texture component,while analysis of the recrystallized substrate showed the[302]α″//ND and[110]α″//ND ***β-phase texture could not be directly measured by XRD,but the presence of the[111]β//ND texture component was successfully predicted by considering the orientation relationship between theα″andβ*** measurements showed that the elastic modulus of the cold-rolled substrate(63GPa)was lower than that of the recrystallized substrate(74GPa).Based on the available literature and the results presented here,it is suggested that this difference is caused by the introduction of crystal defects during cold *** combined nanoindentation/EBSD analysis showed that the nanoindentation results are not affected by crystal *** of the deformed alloy produced changes in hardness,elastic modulus and crystallographic texture similar to those produced by recrystallization heat treatment,creating a stiffness gradient between surface and substrate.

关键词： titanium alloy cold rolling laser surface melting recrystallization crystallographic texture stiffness-graded material

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Reflections on the Green Economy(Redemption of the Principles of Mill and Pigou):A View of a Brazilian Environmentalist

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Journal of Environmental Protection 2014年第12期5卷 1153-1168页

作者： joao batista Drummond Camara Centro Universitario de Brasília UniCeub/ICPDBrasíliaBrazil

The current context of global efforts in the pursuit of sustainable development can be characterized by the perception of the scientific-technological losses of ecosystems and ecosystem services and their consequences for the survival of humanity in the face of threats of imbalances in the basic conditions for survival such as food production, the environmental quality, natural control of pests and diseases, loses of biodiversity and climate changes. Some recent initiatives at global, regional and local level are pointed and some conceptual trends and deployment strategies advance towards the consolidation of the principles of sustainable development, despite several difficulties for effectively reaching its goals. The trend of gradual changes in the models of developing nations and in the patterns of production and consumption is portrayed objectively, seeking to correlate with principles of environmental economics and green economy, since Cecil Pigou and Stuart Mill principles to recent researches as Kenneth Boulding, Herman Daly, Nicholas Georgescu-Rogen, Franz Capra, Ignacy Sachs, Edgar Morin, beyond others. The ability of the United Nations and governments to intervene in neoliberal logic aiming wider benefit to society and the reduction of the negative effects of market distortions, as striking on the global stage, represents a true redemption of the principles advocated by Cecil Pigou, at the beginning of the last century, both for the global economy and for their effects on environmental and social conflicts, social exclusion resulting from the current economic systems which are not necessary new strategies, principles, or economic formulas, but decision making to tackle the market with seriousness to promote equity, social justice and environmental sustainability, without sacrificing progress and development, as evident in the current discussion of social inclusion and the convergence of individual and collective interests, so far in the development model b

关键词： Principles of Environmental Economics Green Economy Sustainable development Productions and Consumption Patterns Environmental Services Anthropogenic Footprint

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Current status and future perspectives of radiomics in hepatocellular carcinoma

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World Journal of Gastroenterology 2023年第1期29卷 43-60页

作者： joao Miranda Natally Horvat Gilton Marques Fonseca Jose de Arimateia batista Araujo-Filho Maria ClaraFernandes Charlotte Charbel Jayasree Chakraborty Fabricio Ferreira Coelho Cesar Higa Nomura Paulo Herman department of Radiology University of Sao PauloSao Paulo 05403-010Brazil department of Radiology Memorial Sloan-Kettering Cancer CenterNew YorkNY 10065United States department of Gastroenterology University of Sao PauloSao Paulo 05403-000Brazil department of Radiology Hospital Sirio-LibanesSao Paulo 01308-050Brazil department of Surgery Memorial Sloan-Kettering Cancer CenterNew YorkNY 10065United States department of Radiology University of Sao PauloSao Paulo 05403-000Brazil

Given the frequent co-existence of an aggressive tumor and underlying chronic liver disease,the management of hepatocellular carcinoma(HCC)patients requires experienced multidisciplinary team ***,imaging plays a key role in the diagnosis,staging,restaging,and surveillance of ***,imaging assessment of HCC entails the assessment of qualitative characteristics which are prone to inter-reader *** is an emerging field that extracts high-dimensional mineable quantitative features that cannot be assessed visually with the naked eye from medical *** main potential applications of radiomic models in HCC are to predict histology,response to treatment,genetic signature,recurrence,and *** the encouraging results to date,there are challenges and limitations that need to be overcome before radiomics implementation in clinical *** purpose of this article is to review the main concepts and challenges pertaining to radiomics,and to review recent studies and potential applications of radiomics in HCC.

关键词： Radiomics Hepatocellular carcinoma Texture analysis Radiology

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How does zebrafish support new strategies for neuroprotection and neuroregeneration in hypoxia-related diseases?

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Neural Regeneration Research 2016年第7期11卷 1069-1070页

作者： Emerson S.Silva joao batista T.Rocha Diogo O.Souza Marcos M.Braga Programa de Pos-Graduacao em Bioquimica Departamento de Bioquimica Instituto de ciencias basicas da saude Universidade Federal do Rio Grande do Sul Porto Alegre RS Brazil Programa de Pos-Graduacao em Bioquimica Toxicologica Departamento de Bioquimica e Biologia Molecular Centro de ciencias Naturais e Exatas Universidade Federal de Santa Maria Santa MariaRS Brazil Instituto Nacional de Ciencia e Tecnologia em Excitotoxicidade e Neuroprotecao Universidade Federal do Rio Grande do Sul PortoAlegre RS Brazil

Hypoxia is a condition found commonly in several disorders,such as ischemia,asthma,anemia and neonatal *** subjected suddenly to high altitude or extreme exercise are also challenged to low oxygen（O2）*** the brain p... 详细信息

关键词： How does zebrafish support new strategies for neuroprotection and neuroregeneration in hypoxia-related diseases

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