21 research outputs found

    GEOCHEMISTRY AND U-Pb GEOCHRONOLOGY OF THE NEOARCHEAN GNEISSES AND PALEOPROTEROZOIC GRANITES FROM JANUÁRIA HIGH: RECORDS OF JUVENILE AND YOUTHFUL EARTH IN THE SÃO FRANCISCO CRATON NUCLEUS (BRAZIL): Geoquímica e geocronologia U-Pb dos gnaisses neoarqueanos e granitos paleoproterozoicos do Alto de Januária: registros da Terra Juvenil e Jovem no núcleo do Cráton São Francisco (Brasil)

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    Within the proposal of secular evolution of the Earth system divided into seven phases: “Proto-Earth” (4.57–4.45 Ga); “Primordial Earth” (4.45–3.80 Ga); “Primitive Earth” (3.8–3.2 Ga); “Juvenile Earth” (3.2–2.5 Ga); “Youthful Earth” (2.5–1.8 Ga); “Middle Earth” (1.8–0.8 Ga); and “Contemporary Earth” (since 0.8 Ga), the 2.61-2.64 Ga High-K, meta- to peraluminous Januária High orthogneisses are inserted in the context of almost rigid behavior of the lithosphere, by the end of the Juvenile Earth. With protolith origin suggestive of intracrustal partial melting of local older TTG (tonalite-trondhjemite-granodiorite), these orthogneisses are the representatives in the São Francisco craton nucleus of the 2.8 Ga to 2.6 Ga potassic rocks found in archean cratons worldwide, and the occurrence of these rocks is a defining characteristic of the Juvenile Earth. Supported on evidence of the plate tectonic activity in Paleoproterozoic, the 2.14-2.19 Ga Januária High biotite granites are inserted in the context of Youthful Earth and they are the record of accretionary orogeny delineated by the edification of magmatic arc at that time. They are calc-alkaline, I-type rocks typical of subduction-related continental magmatic arcs. These biotite granites are probably derived from a High-K mafic source associated with tonalites.ABSTRACT - Within the proposal of secular evolution of the Earth system divided into seven phases: “Proto-Earth” (4.57–4.45 Ga); “Primordial Earth” (4.45–3.80 Ga); “Primitive Earth” (3.8–3.2 Ga); “Juvenile Earth” (3.2–2.5 Ga); “Youthful Earth” (2.5–1.8 Ga); “Middle Earth” (1.8–0.8 Ga); and “Contemporary Earth” (since 0.8 Ga), the 2.61-2.64 Ga High-K, meta- to peraluminous Januária High orthogneisses are inserted in the context of almost rigid behavior of the lithosphere, by the end of the Juvenile Earth. With protolith origin suggestive of intracrustal partial melting of local older TTG (tonalite-trondhjemite-granodiorite), these orthogneisses are the representatives in the São Francisco craton nucleus of the 2.8 Ga to 2.6 Ga potassic rocks found in Archean cratons worldwide, and the occurrence of these rocks is a defining characteristic of the Juvenile Earth. Supported on evidence of the plate tectonic activity in Paleoproterozoic, the 2.14-2.19 Ga Januária High biotite granites are inserted in the context of Youthful Earth and they are the record of accretionary orogeny delineated by the edification of magmatic arc at that time. They are calc-alkaline, I-type rocks typical of subduction-related continental magmatic arcs. These biotite granites are probably derived from a high-K mafic source associated with tonalites. RESUMO - Dentro da proposta da evolução secular do sistema Terra dividido em sete fases: “Proto-Terra” (4,57–4,45 Ga); “Terra Primordial” (4,45–3,80 Ga); “Terra Primitiva” (3,8–3,2 Ga); “Terra Juvenil” (3,2–2,5 Ga); “Terra Jovem” (2,5–1,8 Ga); “Terra Média” (1,8–0,8 Ga); e “Terra Contemporânea” (desde 0,8 Ga), os ortognaisses meta- a peraluminosos de alto-K de 2,61-2,64 Ga do Alto Januária estão inseridos no contexto de comportamento quase rígido da litosfera, no final da “Terra Juvenil”. Com origem de seu protólito sugestiva de fusão parcial intracrustal dos TTG (tonalito-trondhjemito-granodiorito) locais mais antigos, esses ortognaisses são os representantes no interior do cráton do São Francisco das rochas potássicas de 2,8 Ga a 2,6 Ga encontradas em crátons arqueanos em todo o mundo, e a ocorrência dessas rochas é uma característica definidora da “Terra Juvenil”. Apoiados nas evidências da atividade da tectônica de placas no Paleoproterozóico, os biotita granitos de 2,14-2,19 Ga do Alto de Januária estão inseridos no contexto da “Terra Jovem”, são o registro da orogenia acrescionária delineada pela edificação de arco magmático continental nessa época e tratam-se de rochas cálcio-alcalinas do tipo I, típicas de arcos, provavelmente derivadas de uma fonte máfica de alto K associada a tonalitos

    Síndrome de Mccleery: Mccleery Syndrome

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    Introdução: A Síndrome de Mccleery foi descrita detalhadamente a primeira vez em 1951, por Mccleery. É um subtipo da Síndrome do Desfiladeiro Torácico, causada pela obstrução não trombótica da veia subclávia, em que acomete adultos jovens (principalmente do sexo masculino) e atletas, em razão dos esforços repetitivos e da hipertrofia muscular da região torácica. Apresentação do caso: Paciente sexo masculino, 25 anos, atleta, apresenta quadro de dor intensa de início súbito em membro superior direito, seguida de edema e cianose. Relata piora do quadro ao movimentar o membro e melhora parcial com uso de analgésicos e repouso. A ultrassonografia com Doppler identifica compressão de veia subclávia. Realizada venografia que apresentou obstrução de veia subclávia no espaço costoclavicular. Discussão: Nesta síndrome, o espaço costoclavicular, especificamente, ganha destaque. Delimitado entre a primeira costela e a clavícula, onde passam os vasos subclávios e o plexo braquial. Seu diagnóstico é clínico, contudo deve ser associado a exames de imagem. O tratamento é direcionado de acordo com a etiologia e a presença ou não de complicações. Frequentemente a conduta inicial é o tratamento clínico, procurando aliviar os sintomas. No entanto, estudiosos vêm advogando intervenções cirúrgicas precoces, no intuito de evitar eventos trombóticos, limitações funcionais e restrições de mobilidade. Conclusão: O presente relato de caso faz-se importante como contribuição para o literatura  científica, de forma que haja melhor acesso e maior discussão acerca do tema nas plataformas acadêmicas

    Pineocitoma causando Hidrocefalia: Pineocytoma causing Hydrocephalus

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    Introdução: O Pineocitoma é um tumor do sistema nervoso central de caráter benigno. Esse tipo histológico é infrequente correspondendo menos de 1% dos tumores intracranianos. A clínica apresenta desde hipertensão intracraniana até compressão de estruturas nervosas, associado a uma altíssima taxa de morbidade e mortalidade. Apresentação do caso: Paciente com 23anos, sexo feminino, procurou serviço de emergência médica referindo cefaleia intensa de escala de dor 8/10, sem fatores precipitantes e sem melhora com uso de analgésicos ou anti-inflamatório, negou comorbidades e uso de medicações contínuas. Apresenta-se com muita dor, administrando medicação endovenosa para melhorar os sintomas. Foi solicitada uma Tomografia de crânio que evidenciou uma lesão sugestiva de meningioma, paciente foi internada e conduzida para cirurgia para retirada da lesão a qual foi constatada no histopatológico que se tratava de um Pineocitoma. Discussão: o diagnóstico é baseado na clínica, exames de neuroimagem, marcadores tumorais no líquor cefalorraquidiano, o histopatológico já é um exame definitivo, com a tomografia computadorizada de crânio é possível visualizar, massa com contorno bem delimitado, em torno de 3 cm de diâmetro, sendo possível encontrar hidrocefalia associada. O tratamento padrão ouro é ressecção cirúrgica completa, associando a radioterapia e quimioterapia. Conclusão: o tratamento mostra resultado de cura, visto que o Pineocitoma raramente evolui para metástase, resultando em um bom prognóstico devido a evolução tecnológica em tratamento e métodos diagnósticos

    ATLANTIC EPIPHYTES: a data set of vascular and non-vascular epiphyte plants and lichens from the Atlantic Forest

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    Epiphytes are hyper-diverse and one of the frequently undervalued life forms in plant surveys and biodiversity inventories. Epiphytes of the Atlantic Forest, one of the most endangered ecosystems in the world, have high endemism and radiated recently in the Pliocene. We aimed to (1) compile an extensive Atlantic Forest data set on vascular, non-vascular plants (including hemiepiphytes), and lichen epiphyte species occurrence and abundance; (2) describe the epiphyte distribution in the Atlantic Forest, in order to indicate future sampling efforts. Our work presents the first epiphyte data set with information on abundance and occurrence of epiphyte phorophyte species. All data compiled here come from three main sources provided by the authors: published sources (comprising peer-reviewed articles, books, and theses), unpublished data, and herbarium data. We compiled a data set composed of 2,095 species, from 89,270 holo/hemiepiphyte records, in the Atlantic Forest of Brazil, Argentina, Paraguay, and Uruguay, recorded from 1824 to early 2018. Most of the records were from qualitative data (occurrence only, 88%), well distributed throughout the Atlantic Forest. For quantitative records, the most common sampling method was individual trees (71%), followed by plot sampling (19%), and transect sampling (10%). Angiosperms (81%) were the most frequently registered group, and Bromeliaceae and Orchidaceae were the families with the greatest number of records (27,272 and 21,945, respectively). Ferns and Lycophytes presented fewer records than Angiosperms, and Polypodiaceae were the most recorded family, and more concentrated in the Southern and Southeastern regions. Data on non-vascular plants and lichens were scarce, with a few disjunct records concentrated in the Northeastern region of the Atlantic Forest. For all non-vascular plant records, Lejeuneaceae, a family of liverworts, was the most recorded family. We hope that our effort to organize scattered epiphyte data help advance the knowledge of epiphyte ecology, as well as our understanding of macroecological and biogeographical patterns in the Atlantic Forest. No copyright restrictions are associated with the data set. Please cite this Ecology Data Paper if the data are used in publication and teaching events. © 2019 The Authors. Ecology © 2019 The Ecological Society of Americ

    Tradução e adaptação ilustrada.

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    Characterisation of microbial attack on archaeological bone

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    As part of an EU funded project to investigate the factors influencing bone preservation in the archaeological record, more than 250 bones from 41 archaeological sites in five countries spanning four climatic regions were studied for diagenetic alteration. Sites were selected to cover a range of environmental conditions and archaeological contexts. Microscopic and physical (mercury intrusion porosimetry) analyses of these bones revealed that the majority (68%) had suffered microbial attack. Furthermore, significant differences were found between animal and human bone in both the state of preservation and the type of microbial attack present. These differences in preservation might result from differences in early taphonomy of the bones. © 2003 Elsevier Science Ltd. All rights reserved

    Analisando as pesquisas em educação especial no Brasil Analysing research in special education in Brazil

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    Nosso objetivo foi examinar a articulação lógica entre o problema e a proposição teórico-metodológica das produções na área da Educação Especial, focando os seus pressupostos epistemológicos. Nos fundamentamos nos pressupostos das tendências empírico-analítica, fenomenológica-hermenêutica, crítico-dialética e do paradigma da complexidade. O procedimento adotado foi interpretar todas as dissertações/teses produzidas nos Programas de Pós-Graduação em Educação e Educação Especial do Brasil, que versam sobre Educação Especial, produzidas nos anos de 2001, 2002 e 2003, disponíveis no banco de teses da CAPES. Encontramos as tendências empírica, fenomenológica e dialética. Os equívocos encontrados foram a não inserção da pesquisa entre as produções na área; ausência de criticidade; não posicionamento numa determinada concepção de educação; construção teórica fundamentada em concepções diferentes; falta de coerência nos pressupostos teórico-metodológicos; não explicitação metodológica; não descrição dos procedimentos éticos; e má elaboração dos resumos. Concluímos pela necessidade da melhoria das dissertações/teses para que possamos avançar na produção de conhecimento na área da Educação Especial.<br>Our objective was to analyze the logical articulation between the problem and the theoretical-methodological proposal of studies in the field of Special Education, focusing on the epistemological issues. We based our study on the empiric-analytical tendencies, phenomenology-hermeneutic, critical-dialectical and the complexity paradigm. The procedure that was adopted was interpreting all dissertations/thesis produced in Post-Graduate programs in Education and Special Education in Brazil, which focus on Special Education, produced in 2001, 2002 and 2003, available online at CAPES' thesis database. We found empirical, phenomenological and dialectic tendencies. The errors encountered included the failure to include the research among the productions in the field; lack of critical approach; lack of making explicit what educational conception the study was based on; theoretical construction based on different conceptions; lack of coherence in the theoretical-methodological proposals; lack of methodological specification; absence of ethical procedural descriptions; and poorly written abstracts. We came to the conclusion that improvements in theses /dissertations are necessary so as to continually move forward in the production of knowledge in the field of Special Education

    Neotropical freshwater fisheries : A dataset of occurrence and abundance of freshwater fishes in the Neotropics

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    The Neotropical region hosts 4225 freshwater fish species, ranking first among the world's most diverse regions for freshwater fishes. Our NEOTROPICAL FRESHWATER FISHES data set is the first to produce a large-scale Neotropical freshwater fish inventory, covering the entire Neotropical region from Mexico and the Caribbean in the north to the southern limits in Argentina, Paraguay, Chile, and Uruguay. We compiled 185,787 distribution records, with unique georeferenced coordinates, for the 4225 species, represented by occurrence and abundance data. The number of species for the most numerous orders are as follows: Characiformes (1289), Siluriformes (1384), Cichliformes (354), Cyprinodontiformes (245), and Gymnotiformes (135). The most recorded species was the characid Astyanax fasciatus (4696 records). We registered 116,802 distribution records for native species, compared to 1802 distribution records for nonnative species. The main aim of the NEOTROPICAL FRESHWATER FISHES data set was to make these occurrence and abundance data accessible for international researchers to develop ecological and macroecological studies, from local to regional scales, with focal fish species, families, or orders. We anticipate that the NEOTROPICAL FRESHWATER FISHES data set will be valuable for studies on a wide range of ecological processes, such as trophic cascades, fishery pressure, the effects of habitat loss and fragmentation, and the impacts of species invasion and climate change. There are no copyright restrictions on the data, and please cite this data paper when using the data in publications

    Tuberculosis: integrated studies for a complex disease 2050

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    Tuberculosis (TB) has been a disease for centuries with various challenges [1]. Like other places where challenges and opportunities come together, TB challenges were the inspiration for the scientific community to mobilize different groups for the purpose of interest. For example, with the emergence of drug resistance, there has been a huge volume of research on the discovery of new medicines and drug delivery methods and the repurposing of old drugs [2, 3]. Moreover, to enhance the capacity to detect TB cases, studies have sought diagnostics and biomarkers, with much hope recently expressed in the direction of point-of-care tests [4]. Despite all such efforts as being highlighted in 50 Chapters of this volume, we are still writing about TB and thinking about how to fight this old disease–implying that the problem of TB might be complex, so calling the need for an integrated science to deal with multiple dimensions in a simultaneous and effective manner. We are not the first one; there have been proposed integrated platform for TB research, integrated prevention services, integrated models for drug screening, integrated imaging protocol, integrated understanding of the disease pathogenesis, integrated control models, integrated mapping of the genome of the pathogen, etc. [5–12], to name some. These integrated jobs date back decades ago. So, a question arises: why is there a disease named TB yet? It might be due to the fact that this integration has happened to a scale that is not global, and so TB remains to be a problem, especially in resource-limited settings. Hope Tuberculosis: Integrated Studies for a Complex Disease helps to globalize the integrated science of TB.info:eu-repo/semantics/publishedVersio
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