83 research outputs found

    Cellular prion protein interaction with vitronectin supports axonal growth and is compensated by integrins

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    The physiological functions of the cellular prion protein, PrPC, as a cell surface pleiotropic receptor are under debate. We report that PrPC interacts with vitronectin but not with fibronectin or collagen. the binding sites mediating this PrPC-vitronectin interaction were mapped to residues 105-119 of PrPC and the residues 307-320 of vitronectin. the two proteins were co-localized in embryonic dorsal root ganglia from wild-type mice. Vitronectin addition to cultured dorsal root ganglia induced axonal growth, which could be mimicked by vitronectin peptide 307-320 and abrogated by anti-PrPC antibodies. Full-length vitronectin, but not the vitronectin peptide 307-320, induced axonal growth of dorsal root neurons from two strains of PrPC-null mice. Functional assays demonstrated that relative to wild-type cells, PrPC-null dorsal root neurons were more responsive to the Arg-Gly-Asp peptide (an integrin-binding site), and exhibited greater alpha v beta 3 activity. Our findings indicate that PrPC plays an important role in axonal growth, and this function may be rescued in PrPC-knockout animals by integrin compensatory mechanisms.Hosp Alemao Oswaldo Cruz, Ludwig Inst Canc Res, São Paulo, BrazilUniv São Paulo, Inst Quim, Dept Bioquim, BR-05508 São Paulo, BrazilHosp Canc, Ctr Tratamento & Pesquisa, São Paulo, BrazilUniv Fed Parana, Dept Patol Basica, BR-80060000 Curitiba, Parana, BrazilUniv Fed Parana, Dept Biol Celular, BR-80060000 Curitiba, Parana, BrazilUniversidade Federal de São Paulo, INFAR, BR-04023062 São Paulo, BrazilUniversidade Federal de São Paulo, INFAR, BR-04023062 São Paulo, BrazilWeb of Scienc

    Metodologia de análise de um sistema de produção FV para empresa industrial

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    Na última década, o desenvolvimento de sistemas fotovoltaicos (FV) tem contribuído para a evolução da produção de eletricidade utilizando fontes de energia renovável. Os sistemas FV aproveitam a energia que é fornecida pelo sol sob a forma de radiação solar que incide sobre o planeta terra, para a produção de eletricidade. O sol é uma fonte de energia renovável praticamente inesgotável que permite produzir eletricidade livre de poluição (sem emissões de CO2), quando comparado com fontes de energia fóssil. Neste contexto de política energética, vigora atualmente em Portugal o Decreto-Lei n.º 153/2014 que prevê a produção de eletricidade para autoconsumo e a venda à rede elétrica de serviço público (RESP) com recurso a fontes de energia renovável. Pretendese induzir comportamentos de eficiência energética e contribuir para a otimização dos recursos endógenos. A presente dissertação enquadra-se no atual contexto de produção de eletricidade com recurso a fontes de energia renovável para autoconsumo, possuindo como objetivo principal o estudo da viabilidade da instalação de uma fonte FV, para alimentação de dois sistemas de produção de frio numa unidade industrial real, sedeada na região de Viseu. No estudo realizado, analisou-se o perfil solar concreto da zona e o perfil de carga. O primeiro, tendo em conta diversos cenários, como por exemplo, períodos em que a radiação solar é insuficiente para as necessidades energéticas. A abordagem tecnológica baseou-se numa revisão de literatura associada ao tema e à pesquisa sobre as alternativas existentes comercialmente. A estrutura tecnológica proposta engloba aspetos como: a análise da potência a instalar (área); a localização dos módulos FV (problemas de sombreamento) e a seleção dos equipamentos (tipo de tecnologia dos módulos FV, proteções, cabos e inversores). Também a análise de possibilidades de exploração como a venda da energia excedente em períodos que as necessidades energéticas estão satisfeitas, a adaptação da solução ao programa POSEUR (Programa Operacional Sustentabilidade e Eficiência no Uso de Recursos) e a análise económica, são abordadas. Tendo em conta que o trabalho desenvolvido poderá ter interesse por parte das empresas que pretendam instalar um sistema FV, foi elaborada uma ferramenta de apoio que poderá ajudar as empresas a encontrar uma solução mais apropriada para a sua instalação. Tendo as empresas acesso a uma ferramenta deste tipo, dá-se a conhecer a forma como os cálculos do tempo de recuperação do investimento devem ser feitos, nomeadamente tendo em conta que a radiação solar não é constante ao longo do tempo. Deste modo, evitam-se erros de cálculos do tempo de recuperação do investimento que entram com a energia máxima expectável.Abstract: In the last decade the development of photovoltaic systems (PV) has contributed for the evolution of production of electricity using renewable energy sources. PV systems harness the energy provided by the sun (solar radiation) for electricity production. Moreover, the sun is a source of renewable energy practically inexhaustible and free from CO2 emissions when compared to traditional fossil energy sources. In the context of energy policy, Portugal currently uses legislation n.º153/2014 that sustains the self-consumption production of electricity as well as the sale of electricity surplus to the grid (“Rede Elétrica de Serviço Público” RESP) that it is generated from renewable energy sources. It is intended to induce behaviors of energy efficiency and to contribute to optimize endogenous resources. The present dissertation falls in the actual context of electricity production based on renewable sources for self-consumption. Its main goal lies in a feasibility study for the installation of a PV source in an industrial enterprise in the region of Viseu (Portugal), to supply two cooling units. In the present study both the specific solar profile as well as the load profile has been analyzed. The former, considering different scenarios such as periods where solar radiation is insufficient to attain load needs. The technological approach is based on literature review, restrained to commercial alternatives. The proposed structure includes aspects as: analysis of the power to install (PV area); location of modules (shading problems) and selection of equipment (type of module technology, protections, cables and inverters). Analysis of operating potentialities, as the sale of surplus energy in periods where power needs are already satisfied, the adaptation of this solution to the POSEUR (“Programa Operacional Sustentabilidade e Eficiência no Uso de Recursos”) program and economic analysis are also addressed in this study. Enterprises can have interest in this study to install PV systems. A support tool was developed in order to help them to find a more appropriate solution for this type of installations. This tool, among others capabilities, gives an insight about the investment recovery time computation which is a major source of erroneous investment analysis, particularly when taking into consideration that solar radiation is nor constant nor maximal over the time (something that exerts an incorrect but irresistible attraction)

    Enhancing Network Slicing Architectures with Machine Learning, Security, Sustainability and Experimental Networks Integration

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    Network Slicing (NS) is an essential technique extensively used in 5G networks computing strategies, mobile edge computing, mobile cloud computing, and verticals like the Internet of Vehicles and industrial IoT, among others. NS is foreseen as one of the leading enablers for 6G futuristic and highly demanding applications since it allows the optimization and customization of scarce and disputed resources among dynamic, demanding clients with highly distinct application requirements. Various standardization organizations, like 3GPP's proposal for new generation networks and state-of-the-art 5G/6G research projects, are proposing new NS architectures. However, new NS architectures have to deal with an extensive range of requirements that inherently result in having NS architecture proposals typically fulfilling the needs of specific sets of domains with commonalities. The Slicing Future Internet Infrastructures (SFI2) architecture proposal explores the gap resulting from the diversity of NS architectures target domains by proposing a new NS reference architecture with a defined focus on integrating experimental networks and enhancing the NS architecture with Machine Learning (ML) native optimizations, energy-efficient slicing, and slicing-tailored security functionalities. The SFI2 architectural main contribution includes the utilization of the slice-as-a-service paradigm for end-to-end orchestration of resources across multi-domains and multi-technology experimental networks. In addition, the SFI2 reference architecture instantiations will enhance the multi-domain and multi-technology integrated experimental network deployment with native ML optimization, energy-efficient aware slicing, and slicing-tailored security functionalities for the practical domain.Comment: 10 pages, 11 figure

    Desempenho de bezerras leiteiras das raças Pantaneira e Girolando suplementadas ou não durante o período de estiagem na região de Alto-Pantanal Sul-Mato-Grossense.

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    Utilizou-se 24 bezerras desmamadas, distribuídas em dois grupos (raças) com doze animais, por um período de avaliação foi de 94 dias (14 dias de adaptação e três sub-períodos de 28 dias). Os animais foram mantidos em piquetes de capim braquiária (Brachiaria decumbens), em sistema de pastoreio rotacionado. Os tratamentos foram: 1- Pastagem; 2- Suplementado com concentrado (1% peso corpóreo); 3- Suplementado com concentrado mais um aditivo melhorador das funções orgânicas (AMFO); 4- Tratado somente com AMFO (4 injeções de 20 ml). Não houve diferenças estatísticas entre as raças no ganho de peso dos animais, com média de 140,8 e 150,8 gramas/dia para o grupo não suplementado com concentrado e de 321,6 e 448,5 gramas/dia para o grupo suplementado das raças Pantaneira e Girolando, respectivamente. O AMFO não promoveu efeitos significativos (P>0,05) nas variáveis analisadas

    Challenges for sustainable monitoring and evaluation of the EU Marine Strategy Framework Directive in the Atlantic offshore waters: the iFADO project

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    The European Atlantic Area in situ characterization/monitoring is challenging due to the high costs involved (24% of total EU waters for 12% of total population). The implementation of the EU Marine Strategy Framework Directive (MSFD) is complex if the objective is to extend periodic monitoring programs to offshore waters. Remote sensing and modelling have been recognised by the Copernicus Marine Service as suitable methodologies to characterise the global ocean both for nowcast and forecast. iFADO (Innovation in the Framework of the Atlantic Deep Ocean, 2017-2021) is an Interreg Atlantic Area project which main objective is to integrate technologies, including remote sensing, numerical modelling and in situ monitoring, to ease management decisions from MSFD competent authorities. The iFADO project builds on the most recent technologies for data gathering and processing, suited for providing sustainable services to blue economy agents by fostering the regional quadruple helix cooperation (public sector, university/research centres, enterprise and citizens).info:eu-repo/semantics/publishedVersio

    Experimental periodontal disease treatment by subgingival irrigation with tetracycline hydrochloride in rats

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    OBJECTIVE: The aim of this study was to compare subgingival irrigation with tetracycline hydrochloride (TTC-HCL) as adjunctive treatment to scaling and root planning (SRP) on induced periodontitis in rats. MATERIAL AND METHODS: In 60 rats, periodontal disease was ligature-induced at the mandibular left first molar. After 7 days, the ligature was removed and all animals were submitted to SRP, and divided into 2 groups according to the following treatment: C (n=30) - subgingival irrigation with 1 mL of saline; T (n=30) - subgingival irrigation with 1 mL of TTC-HCL (50 mg/mL). Ten animals in each group were euthanized at 7, 15 and 30 days posttreatment. The histometric values were statistically analyzed (p<0.05). RESULTS: In the histometric analysis, at 7, 15 and 30 days, Group T (0.72±0.05 mm(2), 0.57±0.14 mm(2), 0.62±0.07 mm(2)), showed less bone loss (p<0.05) than Group C (1.35±0.25 mm(2); 1.40±0.31 mm(2); 1.29±0.27 mm(2)), respectively. CONCLUSIONS: Subgingival irrigation with TTC-HCL was an effective adjunctive treatment for periodontal disease induced in rats

    Impact of amendments on the physical properties of soil under tropical long-term no till conditions

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    Tropical regions have been considered the world's primary agricultural frontier; however, some physico-chemical deficiencies, such as low soil organic matter content, poor soil structure, high erodibility, soil acidity, and aluminum toxicity, have affected their productive capacity. Lime and gypsum are commonly used to improve soil chemical fertility, but no information exists about the long-term effects of these products on the physical attributes and C protection mechanisms of highly weathered Oxisols. A field trial was conducted in a sandy clay loam (kaolinitic, thermic Typic Haplorthox) under a no-tillage system for 12 years. The trial consisted of four treatments: a control with no soil amendment application, the application of 2.1 Mg ha-1 phosphogypsum, the application of 2.0 Mg ha-1 lime, and the application of lime + phosphogypsum (2.0 + 2.1 Mg ha-1, respectively). Since the experiment was established in 2002, the rates have been applied three times (2002, 2004, and 2010). Surface liming effectively increased water-stable aggregates > 2.0 mm at a depth of up to 0.2 m; however, the association with phosphogypsum was considered a good strategy to improve the macroaggregate stability in subsoil layers (0.20 to 0.40 m). Consequently, both soil amendments applied together increased the mean weight diameter (MWD) and geometric mean diameter (GMD) in all soil layers, with increases of up to 118 and 89%, respectively, according to the soil layer. The formation and stabilization of larger aggregates contributed to a higher accumulation of total organic carbon (TOC) on these structures. In addition to TOC, the MWD and aggregate stability index were positively correlated with Ca2+ and Mg2+ levels and base saturation. Consequently, the increase observed in the aggregate size class resulted in a better organization of soil particles, increasing the macroporosity and reducing the soil bulk density and penetration resistance. Therefore, adequate soil chemical management plays a fundamental role in improving the soil's physical attributes in tropical areas under conservative management and highly affected by compaction caused by intensive farming
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