1,801 research outputs found

    The Challenge of Estimating the Age of Subterranean Lineages: Examples from Brazil

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    The applicability and effectiveness of different kinds of evidence used to estimate the age of lineages – morphological, molecular, phylogenetic, biogeographical, geological – are discussed. Examples from the Brazilian subterranean fauna are presented, using mainly fishes, one of the best studied groups, as a model. Only three taxa including troglobites are object of molecular studies, all in progress. Therefore, molecular clocks cannot be applied yet, and indirect evidence is used. Few phylogenies are available, e.g. for the catfish families Heptapteridae and Trichomycteridae. Theoretically, basal troglobitic clades are older than apical ones, but the possible existence of extinct epigean taxa belonging to such clades hampers the comparison. As well, the limitations of the use degrees of troglomorphism to estimate phylogenetic ages are analyzed with focus on the complexity of the mechanisms underlying morphological differentiation. Paleoclimatic reconstructions based on dating of speleothems from caves in northeastern and southeastern Brazil are available, but limited up to the last 200,000 years, thus useful for relatively recent lineages. Topographic isolation, probable for some fish groups from Central Brazil, is also within the time range of 105 years. Older dated events (in the order of 106 years or more) that may represent vicariant events affecting aquatic lineages with subterranean derivatives are related to the establishment of the modern South American main river basins. In view of the paucity of data useful for estimating the age of Brazilian troglobitic lineages, combined evidence, including morphology, systematics and biogeography, seems to be the best approach at the moment

    Local solutions for a hyperbolic equation

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    Neuromuscular factors affecting stretch-induced torque loss

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    The mechanisms underpinning the immediate torque loss induced by acute, static muscle stretching are still not clear. The current research was designed to examine the neuromuscular factors influencing this torque loss. In Study 1, the contributions of central versus peripheral factors to the stretch-induced torque loss were investigated. Measures of central drive, including the EMG amplitude normalised to the muscle compound action potential amplitude (EMG:M), percent voluntary activation (%VA) and first volitional wave amplitude (V:M), and measures of peripheral function, including the twitch peak torque and 20:80 Hz tetanic torque ratio were made before, and immediately and 15 min after a 5-min continuous plantar flexor stretch. There was a 15.7% (p Alternatively, intermittent (i.e. repeated) stretching commonly performed by athlete and clinical populations causes cycles of ischaemia-reperfusion, increasing the likelihood of contractile failure. Therefore, Study 2 was designed to determine whether intermittent stretch might cause greater torque loss when compared to continuous stretch, and to quantify the potentially greater peripheral effect. The main findings were that intermittent stretch induced a greater torque loss (-23.8%; p Central drive failure can clearly be of spinal origin, and it is reasonable to speculate that muscle stretch might affect the afferent-mediated motor neurone facilitatory system. Thus, in Study 3 a vibration-stimulation protocol (vib+stim) was used to elicit reflexmediated muscular contractions during two experiments. In Experiment 1, vib+stim was imposed with the ankle joint plantar flexed (+10°), neutral (0°) and dorsiflexed (-10°). Torque and EMG amplitudes during vibration and during the self-sustained torque period after vib+stim were greater in dorsiflexion, providing method validation. In Experiment 2, vib+stim was imposed twice before (Control) and immediately, 5, 10 and 15 min after a 5-min intermittent stretch protocol. Torque and EMG amplitude were depressed immediately after stretching during both vibration (-60% and –41%, respectively;

    Origins and Development of Teaching Animal Law in Brazil

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    This paper examines the strategies utilized on each continent and shows the path made for these scholars to build a framework to discuss animal law within law schools. The conclusion is that this movement produced by such scholars has changed the way law schools are teaching law and is affording new opportunities to solve animal concerns, and likewise, social problems in Brazil and around the world. Therefore, this article first discusses the philosophical Brazilian background to teach animal law, and how the animal rights movement creates a framework for professors and students working in this field. It then summarily explores the Brazilian and United States dialogue and how this partnership has expanded the animal law debate in South America, followed by an examination of the civil law countries that have historically influenced the Brazilian system. That section focuses on Portugal, Spain, and France to define new pedagogy to legal education in Brazil while looking at the Brazilian experience in teaching animal law. Some universities have begun to open discussion and create centers to debate this area. The challenge is to change the way of teaching law by showing students that human and non-human interests need to be considered by the law. Finally, this article proposes a direction and some perspectives for the immediate future and explains that it is time to overcome the obstacles and enjoy the atmosphere already shaped to teach animal law as an autonomous subject, that is, as part of the minimum curriculum in Brazilian law schools

    The Future of Nuclear Security in the Asia-Pacific: Expanding the Role of Southeast Asia

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    The nature of regional cooperation on capacity building taking place in Southeast Asia certainly provides a good foundation to pursue a more robust collaborative framework for nuclear security in the wider Asia-Pacific region. A step in this regard is to have a regional action plan/roadmap for nuclear security in the Asia-Pacific that could institutionalize cooperation between Association of Southeast Asian Nations (ASEAN) and other countries in the wider region, fostering closer collaboration. The paper recommends three practical mechanisms to expand cooperation frameworks in Southeast Asia to the broader Asia-Pacific region: (1) strengthening regional capacity building in nuclear security; (2) establishing an ASEAN-Northeast Asia network of nuclear security centers of excellence (COEs) and knowledge centers; and (3) enhancing regional nuclear emergency preparedness and response. The article also explores the future of collaboration among International Nuclear Security Education Network (INSEN) members in the Asia-Pacific region, with Southeast Asian members as key drivers, to further strengthen regional nuclear security governance through sustainable nuclear security education

    A qualidade da democracia: debatendo sua diversidade e o seu exercício

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    GT 2, GT3, GT4 – Calidad de la democracia, comprensión crítica de los derechos humanos y descolonización del derecho y de la polítca em América Latina. “Anais do I Encuentro de Estudios Sociales desde América Latina y el Caribe: cenários linguístico-culturais contemporâneos” - 07, 08 e 09 de novembro de 2013 – UNILA - Coordenação geral: Félix Pablo Friggeri"A qualidade da democracia: debatendo sua diversidade e o seu exercício" tem como objeto de estudo o Conselho Superior Universitário (CONSUNI) e por proposta o debate sobre a elaboração de um processo para inclusão política das diversas nacionalidades neste órgão deliberativo e consultivo da Universidade da Integração Internacional da Lusofonia Afro­ Brasileira, doravante UNILAB, buscando configurar assim um órgão que construa relações de respeito à diversidade e de prática intercultural, conceito que será compreendido no decorrer deste trabalho. Destaque­se que este estudo realizado, segundo o método da observação participante ou pesquisa ação (VERGARA, 2010), fora desenvolvido numa perspectiva discente do processo eleitoral e que se propõe, para além do debate sobre a diversidade e o exercício da democracia, à difusão da experiência no processo eleitoral DISCENTE­ CONSUNI­UNILAB 2013­2014. Pelo que antes se faz necessário falar dos nomes que estiveram participando diretamente na organização deste processo.Universidad Federal de Integración Latino Americana (UNILA) ; Universidad Nacional de Córdoba (UNC
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