5,095 research outputs found

    Effects of Urbanization and the Sustainability of Marine Artisanal Fishing: A Study on Tropical Fishing Communities in Brazil

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    Marine fishing occurs along the coast and oceanic islands within the Exclusive Economic Zone of Brazil and is practiced mainly in an industrial fashion in the southern and southeastern regions of the country as well as in an artisanal fashion in the northern and northeastern regions. Artisanal marine fishing is practiced by fishermen who use sailing rafts or mid-size motorboats in daily fishing activities or activities that surpass 20 days at sea. To face the ocean and extract sustenance and income, the majority of artisanal fishermen do not have advanced fishing technologies, but rather empirical knowledge passed from one generation to another, which has allowed fishermen to maintain their activities for hundreds of years. The shared knowledge with regard to fishing and gear as well as fishing territories and the discovery of new territories allows artisanal fishermen to maintain catches while resources have become scarce. However, different factors in urban areas have been contributing to changes in artisanal marine fishing, such as the facility to education and jobs in other sectors of the economy. The aim of the present study was to investigate the experiences of artisanal fishermen in traditional communities of northeastern Brazil in the occurrence of urbanization. Traditionally in artisanal fishing, the transmission of knowledge occurs in the family, generally from father to son. However, this traditional transmission of knowledge is being lost in urban fishing communities. The urban environment facilitates access to formal education and provides opportunities for both formal and informal jobs, leading to income in more attractive sectors to the sons of fishermen than the activity of fishing. This is caused by changes in schooling and has triggered the avoidance of youths with regard to fishing activities. Moreover, urban pressures, such as the loss of areas of embarkation and landing, further hinder the maintenance of fishing in such areas. Thus, issues related to urbanization have been changing the structure of fishing communities and compromising the maintenance and sustainability of marine artisanal fishing activities in urban areas

    Distribution System Reconfiguration with Variable Demands Using the Opt-aiNet Algorithm

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    This paper describes the application of the Opt-aiNet algorithm to the reconfiguration problem of distribution systems considering variable demand levels. The Opt-aiNet algorithm is an optimization technique inspired in the immunologic bio system and it aims at reproducing the main properties and functions of this system. The reconfiguration problem of distribution networks with variable demands is a complex problem that aims at identifying the most adequate radial topology of the network that complies with all technical constraints in every demand level while minimizing the cost of power losses along an extended operation period. This work includes results of the application of the Opt-aiNet algorithm to distribution systems with 33, 84, 136 and 417 buses. These results demonstrate the robustness and efficiency of the proposed approach

    Educação a distância na ótica discente

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    Este artigo apresenta parte das reflexões desenvolvidas durante uma pesquisa de doutorado que buscou respostas à questão: o que revelam os discursos de estudantes veteranos dos cursos de licenciatura em física e em pedagogia da Universidade Estadual de Maringá, Paraná, a respeito da modalidade de educação a distância e, mais especificamente, dos elementos constitutivos de cada curso? Para tanto, vinte e seis acadêmicos concederam entrevistas, que foram gravadas em áudio, transcritas e compreendidas segundo a teoria da Análise do Discurso de linha francesa, o que permitiu desvelar os sentidos que emanaram dos dizeres dos participantes da pesquisa, sem pretensão de generalizações. O objetivo foi compreender os discursos de estudantes quanto às suas experiências pessoais em cursos de graduação, na modalidade a distância, nos âmbitos estrutural, organizacional e pedagógico. Do resultado das análises, destacaram-se: a forte influência das imagens construídas ao longo da história pela escolarização na modalidade presencial; a facilidade de acesso ao ensino superior via educação a distância (EaD) e sua adequação às condições de vida dos alunos; a preferência dos estudantes pelo livro impresso e pelas videoaulas como suportes à aprendizagem; as resistências, as falhas técnicas e o uso limitado das tecnologias de informação e comunicação (TIC) como mediadores do processo de ensino e de aprendizagem; a presença de fragilidades no processo de comunicação entre tutores e alunos.This article presents reflections developed during PhD research that sought answers to the question: what do the discourses of senior students in undergraduate Physics and Education courses of Universidade Estadual de Maringá, in Paraná state, on distance education and specifically on each course reveal? Twenty-six undergraduate students gave interviews, which were audio-recorded, transcribed and assessed according to the French discourse analysis. This enabled unveiling the meanings that emanated from the discourses of the research participants, without the pretense of generalizations. Our objective was to understand discourses of the students on their personal experience in distance education undergraduate courses, as well as their structural, organizational and educational aspects. The most relevant findings have been: strong influence of images constructed throughout schooling in face-to-face education; easy access to higher education via distance education and its adaptability to the living conditions of students; student preference for printed books and video classes to support learning; resistance, technical failures, and limited use of information and communication technology as mediators of teaching and learning, as well as weaknesses in the communication between tutors and students

    Specialized genetic algorithm of Chu-Beasley applied to the Distribution System Reconfiguration problem considering several demand scenarios

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    This paper describes the application of the specialized genetic algorithm of Chu-Beasley to solve the Distribution System Reconfiguration, DSR, problem considering different demand scenarios. This algorithm is an approach inspired in the natural selection and evolution of species. The reconfiguration problem of distribution networks taking into account different demand scenarios aims at identifying the most adequate radial topology of a distribution system assuming that this topology is used for all demand scenarios under study. This search is driven by the minimization of the cost of energy losses in the network along a full operation year. The performance of the algorithm is evaluated considering test systems having 33, 70, 84 and 136 buses and a real system with 417 buses. The obtained results confirm the robustness and efficiency of the developed approach and its potential to be used in distribution control centers

    Deregulation of apoptosis-related genes is associated with PRV1 overexpression and JAK2 V617F allele burden in Essential Thrombocythemia and Myelofibrosis

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    <p>Abstract</p> <p>Background</p> <p>Essential Thrombocythemia (ET) and Primary Myelofibrosis (PMF) are Chronic Myeloproliferative Neoplasms (MPN) characterized by clonal myeloproliferation/myeloaccumulation without cell maturation impairment. The JAK2 V617F mutation and <it>PRV1 </it>gene overexpression may contribute to MPN physiopathology. We hypothesized that deregulation of the apoptotic machinery may also play a role in the pathogenesis of ET and PMF. In this study we evaluated the apoptosis-related gene and protein expression of BCL2 family members in bone marrow CD34<sup>+ </sup>hematopoietic stem cells (HSC) and peripheral blood leukocytes from ET and PMF patients. We also tested whether the gene expression results were correlated with JAK2 V617F allele burden percentage, <it>PRV1 </it>overexpression, and clinical and laboratory parameters.</p> <p>Results</p> <p>By real time PCR assay, we observed that <it>A1, MCL1, BIK and BID</it>, as well as <it>A1, BCLW </it>and <it>BAK </it>gene expression were increased in ET and PMF CD34<sup>+ </sup>cells respectively, while pro-apoptotic <it>BAX </it>and anti-apoptotic <it>BCL2 </it>mRNA levels were found to be lower in ET and PMF CD34<sup>+ </sup>cells respectively, in relation to controls. In patients' leukocytes, we detected an upregulation of anti-apoptotic genes <it>A1, BCL2, BCL-X<sub>L </sub></it>and <it>BCLW</it>. In contrast, pro-apoptotic <it>BID </it>and <it>BIM<sub>EL </sub></it>expression were downregulated in ET leukocytes. Increased BCL-X<sub>L </sub>protein expression in PMF leukocytes and decreased BID protein expression in ET leukocytes were observed by Western Blot. In ET leukocytes, we found a correlation between JAK2 V617F allele burden and <it>BAX, BIK and BAD </it>gene expression and between <it>A1, BAX </it>and <it>BIK </it>and <it>PRV1 </it>gene expression. A negative correlation between <it>PRV1 </it>gene expression and platelet count was observed, as well as a positive correlation between <it>PRV1 </it>gene expression and splenomegaly.</p> <p>Conclusions</p> <p>Our results suggest the participation of intrinsic apoptosis pathway in the MPN physiopathology. In addition, <it>PRV1 </it>and JAK2 V617F allele burden were linked to deregulation of the apoptotic machinery.</p

    The state of the art of Xyalidae (Nematoda, Monhysterida) with reference to the Brazilian records

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    In the current study we provide a reviewed list of valid genera and species of Xyalidae, a widespread family of mostly marine free-living nematodes. Comments are added about the historic background and taxonomic situation of the family, all valid genera and, when necessary, diagnostic characters are given. Additionally, information about distribution and geographical location of species recorded along the Brazilian coast is provided. Our review recognized 46 valid genera, 450 valid species and 73 descriptions without enough morphological information for identification (species inquerendae). Nearly 80 % of the species inquerendae belong to Daptonema and Theristus. To avoid homonymies, two Daptonema species were renamed, Daptonema biwaensis (Tsalolikhin, 2002) new name (former Mongolotheristus timoshkini) and Daptonema vietnamensis (Gagarin and Thu, 2008) new name (former D. curvatum sensu Gagarin and Thu, 2008). Cenolaimus sapeloensis is transferred to Xyala sapeloensis comb. nov. Along the Brazilian coast 28 genera and 41 species have been recorded. The species Elzalia floresi, Metadesmolaimus tersus, Paramonohystera stricta, Pseudosteineria scopae, Rhynchonema cemae, R. veronicae, Steineria ericia, S. marcorum, S. pavo, S. tripartita, Theristus acribus, T. flevensis, T. macroflevensis, T. pertenuis, T. stranus, Trichotheristus heterus, T. setosus and Zygonemella striata have the Brazilian coast as the type locality. Among all species, three occurred across three geographic regions, while the large majority was restricted to one. Xyalidae is typically encountered in oceanic sandy beaches, with only the species belonging to Daptonema, Theristus, Trichotheristus and Zygonemella being recorded in estuarine sediments. This observation suggests that the colonization of inland waters occurred multiple times along the evolutionary history

    Desenvolvimento de um Sistema de Automação Residencial com a Aplicação de Android e Arduino

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    Neste trabalho apresenta-se o processo de desenvolvimento, construção e testes de um protótipo para automação residencial usando Android e Arduino. Para a implementação do protótipo, foi construída uma maquete de simulação de uma residência, onde foi desenvolvido o sistema de automação usando componentes eletrônicos e Arduino. Já o sistema de controle da automação foi feito usando uma conexão bluetooth e um aplicativo móvel Android, que foi desenvolvido na plataforma App Inventor 2, disponibilizada online pelo MIT (Massachusetts Institute of Technology). Na montagem do protótipo modelo, foram utilizados materiais de baixo custo e foi criado um aplicativo bem simples e de fácil utilização. As funcionalidades implementadas foram: ligar e desligar luzes, abertura e fechamento do portão, medição de temperatura e umidade relativa do ambiente. Estas funcionalidades são genéricas, e representam como pode ser feita a automação de qualquer acionamento elétrico dentro da residência. A principal contribuição com a proposta deste projeto é o desenvolvimento de um ambiente controlado de análise e simulação em pequena escala de um sistema de automação residencial. Por fim, pode-se ressaltar que o sistema desenvolvido é eficiente, possui controle preciso e baixo custo de implementação e operacional, tornando possível a aplicação em sistemas reais

    Granulocyte-Colony Stimulating Factor-Overexpressing Mesenchymal Stem Cells Exhibit Enhanced Immunomodulatory Actions Through the Recruitment of Suppressor Cells in Experimental Chagas Disease Cardiomyopathy

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    Genetic modification of mesenchymal stem cells (MSCs) is a promising strategy to improve their therapeutic effects. Granulocyte-colony stimulating factor (G-CSF) is a growth factor widely used in the clinical practice with known regenerative and immunomodulatory actions, including the mobilization of regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs). Here we evaluated the therapeutic potential of MSCs overexpressing G-CSF (MSC_G-CSF) in a model of inflammatory cardiomyopathy due to chronic Chagas disease. C57BL/6 mice were treated with wild-type MSCs, MSC_G-CSF, or vehicle (saline) 6 months after infection with Trypanosoma cruzi. Transplantation of MSC_G-CSF caused an increase in the number of circulating leukocytes compared to wild-type MSCs. Moreover, G-CSF overexpression caused an increase in migration capacity of MSCs to the hearts of infected mice. Transplantation of either MSCs or MSC_G-CSF improved exercise capacity, when compared to saline-treated chagasic mice. MSC_G-CSF mice, however, were more potent than MSCs in reducing the number of infiltrating leukocytes and fibrosis in the heart. Similarly, MSC_G-CSF-treated mice presented significantly lower levels of inflammatory mediators, such as IFNγ, TNFα, and Tbet, with increased IL-10 production. A marked increase in the percentage of Tregs and MDSCs in the hearts of infected mice was seen after administration of MSC_G-CSF, but not MSCs. Moreover, Tregs were positive for IL-10 in the hearts of T. cruzi-infected mice. In vitro analysis showed that recombinant hG-CSF and conditioned medium of MSC_G-CSF, but not wild-type MSCs, induce chemoattraction of MDSCs in a transwell assay. Finally, MDSCs purified from hearts of MSC_G-CSF transplanted mice inhibited the proliferation of activated splenocytes in a co-culture assay. Our results demonstrate that G-CSF overexpression by MSCs potentiates their immunomodulatory effects in our model of Chagas disease and suggest that mobilization of suppressor cell populations such as Tregs and MDSCs as a promising strategy for the treatment of chronic Chagas disease. Finally, our results reinforce the therapeutic potential of genetic modification of MSCs, aiming at increasing their paracrine actions

    Observation of two new Ξb\Xi_b^- baryon resonances

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    Two structures are observed close to the kinematic threshold in the Ξb0π\Xi_b^0 \pi^- mass spectrum in a sample of proton-proton collision data, corresponding to an integrated luminosity of 3.0 fb1^{-1} recorded by the LHCb experiment. In the quark model, two baryonic resonances with quark content bdsbds are expected in this mass region: the spin-parity JP=12+J^P = \frac{1}{2}^+ and JP=32+J^P=\frac{3}{2}^+ states, denoted Ξb\Xi_b^{\prime -} and Ξb\Xi_b^{*-}. Interpreting the structures as these resonances, we measure the mass differences and the width of the heavier state to be m(Ξb)m(Ξb0)m(π)=3.653±0.018±0.006m(\Xi_b^{\prime -}) - m(\Xi_b^0) - m(\pi^{-}) = 3.653 \pm 0.018 \pm 0.006 MeV/c2/c^2, m(Ξb)m(Ξb0)m(π)=23.96±0.12±0.06m(\Xi_b^{*-}) - m(\Xi_b^0) - m(\pi^{-}) = 23.96 \pm 0.12 \pm 0.06 MeV/c2/c^2, Γ(Ξb)=1.65±0.31±0.10\Gamma(\Xi_b^{*-}) = 1.65 \pm 0.31 \pm 0.10 MeV, where the first and second uncertainties are statistical and systematic, respectively. The width of the lighter state is consistent with zero, and we place an upper limit of Γ(Ξb)<0.08\Gamma(\Xi_b^{\prime -}) < 0.08 MeV at 95% confidence level. Relative production rates of these states are also reported.Comment: 17 pages, 2 figure

    Measurement of the Bs0J/ψηB_{s}^{0} \rightarrow J/\psi \eta lifetime

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    Using a data set corresponding to an integrated luminosity of 3fb13 fb^{-1}, collected by the LHCb experiment in pppp collisions at centre-of-mass energies of 7 and 8 TeV, the effective lifetime in the Bs0J/ψηB^0_s \rightarrow J/\psi \eta decay mode, τeff\tau_{\textrm{eff}}, is measured to be τeff=1.479±0.034 (stat)±0.011 (syst)\tau_{\textrm{eff}} = 1.479 \pm 0.034~\textrm{(stat)} \pm 0.011 ~\textrm{(syst)} ps. Assuming CPCP conservation, τeff\tau_{\textrm{eff}} corresponds to the lifetime of the light Bs0B_s^0 mass eigenstate. This is the first measurement of the effective lifetime in this decay mode.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2016-017.htm
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