1,660 research outputs found

    Spatial and temporal dynamics of the abundance of crustose calcareous algae on the southernmost coral reefs of the western Atlantic (Abrolhos Bank, Brazil)

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    Crustose calcareous algae (CCA) constitute one of the main reef builders on the Abrolhos Bank, Brazil. Once CCA taxonomy is locally understood, differences in growth-forms may be useful for the delimitation of taxa using characteristics such as the presence or absence of surface protuberances. Here, growth-forms were used to identify and quantify the most common CCA taxa on the shallow reefs (3-10 m) of the Abrolhos Bank to determine possible changes in the CCA community over a period of 10 years, and the ecological significance of CCA to local reefs was interpreted. The CCA assemblages were surveyed from 2006-2015 by using fixed photoquadrats at four sites in the inner (10-20 km from the mainland) and mid-shelf reefs (40-75 km from the mainland). The five most common CCA taxa were Pneophyllum conicum, the Lithophyllum kaiserii / Lithophyllum sp. complex, Melyvonnea erubescens, the Hydrolithon boergesenii / Porolithon onkodes complex and Peyssonelia sp. The overall mean CCA cover on the reefs was 20%. A comparison with a previous monitoring study in the same region indicated that the CCA cover nearly doubled from 2003-2008 to 2006-2015. This study reveals that the coral-killing species P. conicum dominated CCA flora on the shallow Abrolhos reefs in the last decade, and the local specific abundance of CCA slightly fluctuated over time and was species-and site-specific. The information obtained in this study contributes to the understanding of the ecology of the key calcifying components of the Abrolhos reefs and provides a useful baseline for exploring the responses of CCA to future environmental changes.PELDMudancas Climaticas scientific programmes of the Brazilian National Science Agency (CNPq)Brazilian IODP Program (CAPES/MEC)P&D Program ANP/BrasoilFAPERJDiretoria Pesquisa Cient, Inst Pesquisas, Jardim Bot Rio De Janeiro, Rua Pacheco Leao 915, BR-22460030 Rio De Janeiro, RJ, BrazilUniv Fed Rio de Janeiro, Inst Biol, BR-21941599 Rio De Janeiro, RJ, BrazilUniv Fed Espirito Santo, Dept Oceanog, Ave Fernando Ferrari 514, BR-29090600 Vitoria, ES, BrazilUniv Fed Sao Paulo, Inst Mar, Campus Baixada Santista, BR-11030400 Santos, SP, BrazilUniv Fed Paraiba, Ctr Ciencias Aplicadas & Educ, Campus 4 Litoral Norte, BR-58297000 Rio Tinto, PB, BrazilUniv Fed Sao Paulo, Inst Mar, Campus Baixada Santista, BR-11030400 Santos, SP, BrazilANP/Brasoil: 48610.011015/2014-55Web of Scienc

    Human-machine interfaces based on EMG and EEG applied to robotic systems

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    <p>Abstract</p> <p>Background</p> <p>Two different Human-Machine Interfaces (HMIs) were developed, both based on electro-biological signals. One is based on the EMG signal and the other is based on the EEG signal. Two major features of such interfaces are their relatively simple data acquisition and processing systems, which need just a few hardware and software resources, so that they are, computationally and financially speaking, low cost solutions. Both interfaces were applied to robotic systems, and their performances are analyzed here. The EMG-based HMI was tested in a mobile robot, while the EEG-based HMI was tested in a mobile robot and a robotic manipulator as well.</p> <p>Results</p> <p>Experiments using the EMG-based HMI were carried out by eight individuals, who were asked to accomplish ten eye blinks with each eye, in order to test the eye blink detection algorithm. An average rightness rate of about 95% reached by individuals with the ability to blink both eyes allowed to conclude that the system could be used to command devices. Experiments with EEG consisted of inviting 25 people (some of them had suffered cases of meningitis and epilepsy) to test the system. All of them managed to deal with the HMI in only one training session. Most of them learnt how to use such HMI in less than 15 minutes. The minimum and maximum training times observed were 3 and 50 minutes, respectively.</p> <p>Conclusion</p> <p>Such works are the initial parts of a system to help people with neuromotor diseases, including those with severe dysfunctions. The next steps are to convert a commercial wheelchair in an autonomous mobile vehicle; to implement the HMI onboard the autonomous wheelchair thus obtained to assist people with motor diseases, and to explore the potentiality of EEG signals, making the EEG-based HMI more robust and faster, aiming at using it to help individuals with severe motor dysfunctions.</p

    Different views of community based tourism of marine extractive Reserve of Soure, Amazonia (Brazil).

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    As Reservas Extrativistas t?m como prote??o b?sica a sociobiodiversidade. Uma das alternativas de uso p?blico sustent?vel se d? pelo turismo, que est? sujeito a gerar impactos negativos. Assim, o presente trabalho aborda os diferentes olhares do Turismo de Base Comunit?ria (TBC) na Reserva Extrativista Marinha de Soure (RESEXMS). A pesquisa de cunho explorat?rio e estudo de caso se deram por meio de revis?o bibliogr?fica, elabora??o de instrumento de coleta de dados (question?rios estruturados qualitativos) e 16 entrevistas a 11 representantes do conselho deliberativo (poder p?blico, setor privado e sociedade civil organizada) e turistas. Complementarmente houve observa??o participante por meio de est?gio volunt?rio na unidade de conserva??o. Como resultados observouse que o TBC ? um importante transformador socioecon?mico, cultural e ambiental, no entanto sendo necess?ria uma maior articula??o dele enquanto participa??o ativa dos atores sociais, para maior efetividade de gest?o da ?rea protegida.The basic function of extractive reserves is protecting sites? sociobiodiversity. One alternative for sustainable public use of extractive reserves is tourism, which may have negative effects on the reserves? socio-biodiversity. Therefore, the present work addresses different perspectives of Community-Based Tourism (CBT) in the Marine Extractive Reserve of Soure, Brazil. The exploratory research and case study presented in this work include a bibliographic review, qualitative structured questionnaires, and 16 interviews with 11 representatives of the deliberative council, which includes members from the government, the private sector and organized civil society as well as tourists. In addition, participation as an observer through a voluntary internship in the protected area. Results show that the CBT is an important transformation agent of the socio-economic, cultural, and environmental conditions of the reserve. However, it is necessary to increase its articulation as active participation of the stakeholders to improve the effectiveness of reserve management

    Reef fish and benthic assemblages of the Trindade and Martin Vaz Island group, southwestern Atlantic

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    O conjunto insular de Trindade e Martin Vaz (CITMV) está localizado a aproximadamente 1.120 km da costa brasileira. Apesar de sua importância, salientada pela presença de diversas espécies endêmicas de peixes, não existem informações detalhadas sobre as assembléias de peixes e bentos do CITMV. É apresentada aqui a primeira caracterização quantitativa das assembléias de peixes e bentos do CITMV em um gradiente de profundidade entre 5 e 45 m. Informações qualitativas adicionais sobre assembléias recifais entre 45 e 100 m foram obtidas utilizando-se técnicas avançadas de mergulho (TRIMIX) e um veículo de operação remota (VOR). Assim como outras ilhas oceânicas brasileiras, a CITMV possui assembléias depauperadas de peixes e bentos, possivelmente devido ao seu isolamento e pequeno tamanho em comparação ao continente. A profundidade foi o fator que mais afetou a estrutura das assembléias de peixes, com a densidade da maioria das espécies declinando com o aumento da profundidade. Os recifes profundos (>; 45 m) foram caracterizados pela presença de bancos extensivos de rodolitos e recifes rochosos esparsamente cobertos por algas coralináceas incrustantes, corais negros (Cirripathes sp.) e alguns corais massivos e em de forma de placa. Peixes parcialmente ou obrigatoriamente planctívoros (e.g. Cephalopholis furcifer and Clepticus brasiliensis) também dominaram em recifes profundos. Características similares foram registradas para recifes mesofóticos ao longo do Atlântico Ocidental. Evidências de sobrepesca (obtidas aqui e em outros estudos recentes), a presença de quatro espécies de peixes endêmicas e com distribuição restrita, e o aumento no número de espécies novas ainda não descritas, indicam que a adoção de medidas de conservação baseadas no princípio da precaução é urgentemente necessária para garantir a manutenção dos ecossistemas frágeis e únicos do CITMV.The Trindade and Martin Vaz island group (TMVIG) is located at about 1,120 km off the Brazilian coast. Despite its importance, highlighted by the presence of several endemic fish species, the TMVIG lacks detailed information on the structure of fish and benthic assemblages. Presented here is the first quantitative assessment of reef fish and benthic assemblages of the TMVIG in a depth gradient ranging from 5 to 45 m. Additional qualitative information on reef assemblages between 45 and 100 m was obtained using advanced gas diving techniques (TRIMIX) and a remotely operated vehicle (ROV). Similarly to other Brazilian oceanic islands, the TMVIG possesses depauperated fish and benthic assemblages, possibly due to its isolation and small size in comparison to the mainland. Depth was the most important factor affecting the structure of fish assemblages, with the density of most fish species declining with depth. Deep reefs (>; 45 m) were characterized by the presence of extensive rhodolith beds and rocky reefs sparsely covered with crustose coralline algae, black coral (Cirripathes sp.) and a few massive or plate-like reef corals. Part-time or obligatory planktivorous fishes (e.g. Cephalopholis furcifer and Clepticus brasiliensis) also dominated deep reefs. Similar characteristics were recorded in mesophotic reef ecosystems across the Western Atlantic. Evidence of overfishing (obtained here and in other recent studies), the presence of four endemic and restricted range fish species, as well as the increase in number of new (and still undescribed) endemic taxa, indicates that the adoption of precautionary conservation measures are urgently needed in order to maintain the fragile and unique ecosystems of the TMVIG

    Caderno de pós-graduação em direito: regulação econômica e tributos

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    O presente ebook é formado por diversos artigos relacionas a temática da tributação e economia, especialmente, no que se refere regulação econômica por meio da tributação ou como consequência da adoção de determinadas políticas tributárias no país, o que reflete diretamente nos caminhos que o pais adota e poderão ou não impactar no seu crescimento, abordando inclusive temas como economia digital e tributação que ainda carecem muito de estudos sobre o seu desenvolvimento

    Mesophotic reef fish assemblages of the remote St. Peter and St. Paul's Archipelago, Mid-Atlantic Ridge, Brazil

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    Mesophotic reef fish assemblages (30-90 m depth) of the small and remote St. Peter and St. Paul's Archipelago (SPSPA), Mid-Atlantic Ridge, Brazil, were characterized using remotely operated vehicles. Ordination analyses identified distinct fish assemblages in the upper (30-50 m) and lower (50-90 m) mesophotic zones, the former characterized by high abundances of species that are also abundant at euphotic reefs (Caranx lugubris, Melichthys niger, Stegastes sanctipauli and Chromis multilineata) and the latter dominated by two mesophotic specialists (Prognathodes obliquus and Chromis enchrysura). Planktivores dominated fish assemblages, particularly in the upper mesophotic zone, possibly due to a greater availability of zooplankton coming from the colder Equatorial Undercurrent in mesophotic depths of the SPSPA. Turf algae, fleshy macroalgae and scleractinian corals dominated benthic assemblages between 30 and 40 m depth, while bryozoans, black corals and sponges dominated between 40 and 90 m depth. Canonical correspondence analysis explained 74 % of the relationship between environmental characteristics (depth, benthic cover and complexity) and structure of fish assemblages, with depth as the most important independent variable. Juveniles of Bodianus insularis and adults of P. obliquus and C. enchrysura were clearly associated with branching black corals (Tanacetipathes spp.), suggesting that black corals play key ecological roles in lower mesophotic reefs of the SPSPA. Results from this study add to the global database about mesophotic reef ecosystems (MREs) and provide a baseline for future evaluations of possible anthropogenic and natural disturbances on MREs of the SPSPA.Conselho Nacional de Desenvolvimento Cientifico e Tecnologico-CNPqCNPqFundacao de Amparo a Pesquisa do Estado do Rio de Janeiro (FAPERJ)Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)Univ Sao Paulo, Inst Oceanog, Programa Posgrad Oceanog Biol, BR-05508120 Sao Paulo, SP, BrazilUniv Fed Paraiba, Programa Posgrad Ciencias Biol Zool, BR-58059900 Joao Pessoa, PB, BrazilUniv Fed Paraiba, Programa Posgrad Ecol & Monitoramento Ambiental, BR-58297000 Rio Tinto, PB, BrazilUniv Estadual Paraiba, Programa Posgrad Ecol & Conservac, BR-58109753 Campina Grande, PB, BrazilUniv Fed Pernambuco, Dept Oceanog, Ctr Tecnol & Geociencias, BR-50670901 Recife, PE, BrazilUniv Fed Paraiba, Ctr Ciencias Exatas & Nat, Dept Sistemat & Ecol, BR-58051900 Joao Pessoa, PB, BrazilInst Pesquisas Jardim Bot Rio De Janeiro, Rio De Janeiro, RJ, BrazilUniv Fed Sao Paulo, Inst Mar, Campus Baixada Santista, BR-11030400 Santos, SP, BrazilUniv Fed Rio de Janeiro, Inst Biol, BR-21944970 Rio De Janeiro, RJ, BrazilUniv Fed Rio de Janeiro, SAGE COPPE, BR-21944970 Rio De Janeiro, RJ, BrazilUniv Sao Paulo, Inst Oceanog, Dept Oceanog Biol, BR-05508120 Sao Paulo, SP, BrazilUniv Fed Paraiba, Dept Engn & Meio Ambiente, BR-58297000 Rio Tinto, PB, BrazilUniv Fed Sao Paulo, Inst Mar, Campus Baixada Santista, BR-11030400 Santos, SP, BrazilCNPq: 557185/09-2CNPq: 484875/2011-6Web of Scienc
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