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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

Dynamic Instability of Straight Bars Subjected to Impulsive Axial Loads Using the DEM

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Computer Modeling in Engineering & Sciences 2015年第2期104卷 87-104页

作者： Leticia Fleck Fadel Miguel Leandro Fleck Fadel Miguel joao Kaminski jr. Department of Mechanical Engineering UFRGSPorto AlegreRSBrazil Department of Civil Engineering UFSCFlorianopolisSCBrazil Department of Structures and Civil Construction UFSMSanta MariaRSBrazil

Since the half of the XX century,attention was given to the instability of structures under parametric excitation,especially under periodic *** the other hand,the instability of bars subjected to axial loads of impulsive type has been little studied,in spite of the practical importance of the ***,in Engineering Design it is frequently supposed,without tests or additional verifications,that an axial load of short duration can exceed the Euler critical load of the bar without inducing damage in the *** this context,this paper proposes the use of the truss-like Discrete Element Method(DEM)for determining the dynamic response of elastic straight bars subjected to axial loads defined by pulses of short *** proposed approach allows the consideration of initial imperfections,as well as large displacements and other non-linear *** influence of the pulse duration and other effects in the response of the bar are also ***,the performance of the proposed methodology is verified in static and dynamic instability problems of homogeneous bars without geometrical imperfections,by comparing the DEM results with analytical solutions available in the *** that,the DEM is employed to analyze more complex cases,including bars with initial imperfections and non-homogeneous bars,in which material properties,as Young’s modulus and mass density,are assumed to be correlated Gaussian random *** proposed methodology has proven to be a useful and easy tool for analysis of dynamic instability of bars and could therefore be used by designers for estimating the dynamic buckling load.

关键词： Dynamic Instability Critical Buckling Load Discrete Element Method Impulsive Load Stochastic Fields Mesh Imperfections

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

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

Transesterification of sunflower oil in microchannels with circular obstructions

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Chinese Journal of Chemical Engineering 2018年第4期26卷 852-863页

作者： Harrson S.Santana joao L.Silva jr Deborah S.Tortola Osvaldir P.Taranto School of Chemical Engineering University of Campinas13083-852 CampinasSPBrazil Federal Institute of Education Science and Technology of South of Minas Gerais-IFSULDEMINAS37560-260 Poaso AlegreMGBrazil

The present paper studied numerical and experimentally the transesterification reaction between sunflower oil and ethanol with NaO H catalyst in microchannels with circular obstructions. The micromixer design influence on fluid mixing and oil conversion was investigated for a range of operating conditions: Reynolds number(Re = 0.1–100),Temperature(25–75 °C), ethanol/oil molar ratio(6-12), and catalyst concentration(0.75 wt%–1.25 wt%), using three microchannel configurations(Length = 35 mm; Width = 1500 μm; Height = 200 μm): T-shape – channel without obstructions; MCO – channel with 3 obstructions ensemble – equally disposed over longitudinal length;MWO – channel with 7 obstructions ensemble. The MCO micromixer was based on literature work, and the MWO is a totally new micromixer design. Experimental tests were conducted in similar conditions in microreactors using these micromixers(Length = 411 mm) made of polydimethylsiloxane. The MCO configuration presented the highest performance(mixing index of 0.80 at Re = 100), oil conversion of 81.13% at 75 °C, molar ratio of 9 and catalyst concentration of 1%. Experimental results showed high conversions for MCO and MWO configurations(99.99%) at 50 °C, molar ratio of 9 and catalyst concentration of 1%, with a residence time of 12 s.

关键词： Biodiesel Sunflower oil-ethanol Transesterification reaction Circular obstructions Microreactor Numerical simulation

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

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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.

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

Comparison between the Energy Required for Production of PV Module and the Output Energy Througout the Product Life Time

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Journal of Energy and Power Engineering 2015年第6期9卷 592-597页

作者： Lea Beatriz Dai Pra joao batista Dias Amanda Goncalves Kieling Laboratorio de Energias Renovaveis UNISINOS (Universidade do Vale do Rio dos Sinos) Sao Leopoldo 93.022-000 Brazil

Electrical energy consumption is growing and is necessary to improve the technologies related to energy production. We have carried out a pilot study about environmental impacts during the manufacturing process of PV （photovoltaic） modules and compared between the energy requirement for the production of PV cells and modules and generation throughout the life time of the finished good that is PV module. It was taken into account the generation of environmental aspects and impacts in the manufacture of monocrystalline silicon PV modules （consisting of three components： silicon cell, fiat tempered glass and aluminum frame）, and an analysis of a grid-connected PV system using an energetic alternative in residences was considered. Results show that, this kind of renewable energy is really clean and can be considered as a way to change the energy technology.

关键词： Manufacturing of PV modules generation of environmental impacts grid-connected PV system.

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