952 resultados para Dubious origins


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Theory of Mind (ToM) is the cognitive achievement that enables us to report our propositional attitudes, to attribute such attitudes to others, and to use such postulated or observed mental states in the prediction and explanation of behavior. Most normally developing children acquire ToM between the ages of 3 and 5 years, but serious delays beyond this chronological and mental age have been observed in children with autism, as well is in those with severe sensory impairments. We examine data from Studies of ToM in normally developing children and those with deafness, blindness, autism and Williams syndrome, as well as data from lower primates, in a search for answers to key theoretical questions concerning the origins, nature and representation of knowledge about the mind. In answer to these, we offer a framework according to which ToM is jointly dependent upon language and social experience, and is produced by a conjunction of language acquisition with children's growing social understanding, acquired through conversation and interaction with others. We argue that adequate language and adequate social skills are jointly causally sufficient, and individually causally necessary, for producing ToM. Thus our account supports a social developmental theory of the genesis of human cognition, inspired by the work of Sellars and Vygotsky.

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We inferred the phylogeny of 33 species of ticks from the subfamilies Rhipicephalinae and Hyalomminae from analyses of nuclear and mitochondrial DNA and morphology. We used nucleotide sequences from 12S rRNA, cytochrome c oxidase I, internal transcribed spacer 2 of the nuclear rRNA, and 18S rRNA. Nucleotide sequences and morphology were analyzed separately and together in a total-evidence analysis. Analyses of the five partitions together (3303 characters) gave the best-resolved and the best-supported hypothesis so far for the phylogeny of ticks in the Rhipicephalinae and Hyalomminae, despite the fact that some partitions did not have data for some taxa. However, most of the hidden conflict (lower support in the total-evidence analyses compared to that in the individual analyses) was found in those partitions that had taxa without data. The partitions with complete taxonomic sampling had more hidden support (higher support in the total-evidence analyses compared to that in the separate-partition analyses) than hidden conflict. Mapping of geographic origins of ticks onto our phylogeny indicates an African origin for the Rhipicephalinae sensu lato (i.e., including Hyalomma spp.), the Rhipicephalus-Boophilus lineage, the Dermacentor-Anocentor lineage, and the Rhipicephalus-Booophilus-Nosomma-Hyalomma-Rhipicentor lineage. The Nosomma-Hyalomma lineage appears to have evolved in Asia. Our total-evidence phylogeny indicates that (i) the genus Rhipicephalus is paraphyletic with respect to the genus Boophilus, (ii) the genus Dermacentor is paraphyletic with respect to the genus Anocentor, and (iii) some subgenera of the genera Hyalomma and Rhipicephalus are paraphyletic with respect to other subgenera in these genera. Study of the Rhipicephalinae and Hyalomminae over the last 7 years has shown that analyses of individual datasets (e.g., one gene or morphology) seldom resolve many phylogenetic relationships, but analyses of more than one dataset can generate well-resolved phylogenies for these ticks. (C) 2001 Academic Press.

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Dendritic cells (DC) are now recognised as a unique leukocyte type, consisting of two or more subsets. The origins and functional inter-relationships of these cells are the subject of intense basic scientific investigation. They play important roles in initiating and directing immune responses, defending the host from pathogens and maintaining self tolerance. Fundamental studies are defining new molecules and mechanisms associated with DC function. The first methods for counting these rare blood cell populations are already providing interesting new clinical data. Indeed, abnormal DC function may contribute to deficiencies in the immune response against malignancies. Phase I trial data suggests that DC-based cancer vaccination protocols may contribute an important new biological approach to cancer therapy. Manipulation of DC to facilitate allogeneic transplantation and even to manage autoimmune disease are likely developments.

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The origins of the oxygen atoms in 1,7-dioxaspiro[5.5]undecane (1) and hydroxyspiroacetal (2) from Bactrocera cacuminata, and in 2,8-dimethyl-1,7-dioxaspiro[5.5]undecane (3) and hydroxyspiroacetal (4) from B. cucumis, have been investigated by incorporation studies from both [18O2]-dioxygen and [18O]-water. Combined GC-MS examination and high-field NMR analysis have demonstrated that all oxygen atoms in 1 and 2 from B. cacuminata are dioxygen derived, but in contrast, the spiroacetals 3 and 4 from B. cucumis incorporate one ring oxygen from water and one ring oxygen (and the hydroxyl oxygen in 4) from [18O2]-dioxygen. These results reveal not only the generality of monoxygenase mediation of spiroacetal formation in Bactrocera sp., but also an unexpected complexity in their biosynthesis. A general paradigm accommodating these and other observations is presented.

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Picornavirus RNA replication requires the formation of replication complexes (RCs). consisting of virus-induced vesicles associated with viral nonstructural proteins and RNA. Brefeldin A (BFA) has been shown to strongly inhibit RNA replication of poliovirus but not of encephalomyocarditis virus (EMCV). Here, we demonstrate that the replication of parechovirus 1 (ParV1) is partly resistant to BFA, whereas echovirus 11 (EV11) replication is strongly inhibited. Since BFA inhibits COPI-dependent steps in endoplasmic reticulum (ER)-Golgi transport, we tested a hypothesis that different picornaviruses may have differential requirements for COPI in the formation of their RCs. Using immunofluorescence and cryo-immunoelectron microscopy we examined the association of a COPI component, beta-COP, with the RCs of EMCV, ParV1, and EV11 EMCV RCs did not contain beta-COP. In contrast, beta-COP appeared to be specifically distributed to the RCs of EV11 In ParV1-infected cells beta-COP was largely dispersed throughout the cytoplasm, with some being present in the RCs. These results suggest that there are differences in the involvement of COPI in the formation of the RCs of various picornaviruses, corresponding to their differential sensitivity to BFA. EMCV RCs are likely to be formed immediately after vesicle budding from the ER, prior to COPI association with membranes. ParV1 RCs are formed from COPI-containing membranes but COPI is unlikely to be directly involved in their formation, whereas formation of EV11 RCs appears to be dependent on COPI association with membranes.

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Mangroves are often described as a group of plants with common features and common origins based mostly on their broad distributional patterns, together with an erroneous view of comparable abilities in long-distance dispersal. However, whilst mangroves have common needs to adapt to rigorous environmental constraints associated with regular seawater inundation, individual taxa have developed different strategies and characteristics. Since mangroves are a genetically diverse group of mostly flowering plants, they may also have evolved at quite different geological periods, dispersed at different rates from different locations and developed different adaptive strategies. Current distributions of individual taxa show numerous instances of unusual extant distribution which demonstrate finite dispersal limitations, especially across open water. Our preliminary assessment of broad distribution and discontinuities reveals important patterns. Discontinuities, in the absence of current dispersal barriers, may be explained by persistent past barriers. As we learn more about discontinuities, we are beginning to appreciate their immense implications and what they might tell us about past geological conditions and how these might have influenced the distribution and evolution of mangroves. In this article, we describe emerging patterns in genetic relationships and distributions based on both current knowledge and preliminary results of our studies of molecular and morphometric characteristics of Rhizophora species in the Indo West Pacific region.

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If open reading frames (ORFs) have been transmitted primarily by vertical descent, the distributional profile of orthologues of each ORF should be congruent with the organismal tree or a subtree thereof. Distributional patterns not reconciled parsimoniously with tree-like descent and loss are prima facie evidence of lateral gene transfer. Herein, a rigorous criterion for recognizing ORF distributions is described and implemented; it does not require the inference of phylogenetic trees, nor does it assume any specific tree. Because lineage-specific differences in rates of sequence change can also generate unexpected distributional patterns, rate artefacts, were controlled for by requiring pairwise matches between ORFs to exceed a rigorous inclusion threshold, but absence of a match was assessed against a more-permissive exclusion threshold. Applying this dual-threshold criterion to cross-domain and cross-phylum distributional patterns for ORFs in 23 bacterial genomes, a relative abundance of ORFs was observed that find a match in exactly seven other bacterial phyla; 94-99% of these ORFs also find matches among the Archaea and/or Eukarya. In the larger (and some smaller) bacterial genomes, ORFs that find matches in exactly one other bacterial phylum are also relatively abundant, but fewer of these have non-bacterial homologues; most of their matches within the Bacteria are to the Proteobacteria and/or Firmicutes, which cannot be sister lineages to all bacteria. ORFs that are neither distributed universally among the Bacteria, nor necessarily shared with topologically adjacent lineages, are preferentially enriched in large bacterial genomes.

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The central nucleus of the amygdala (CeA) is activated robustly by an immune challenge such as the systemic administration of the proinflammatory cytokine interleukin-1beta (IL-1beta). Because IL-1beta is not believed to cross the blood-brain barrier in any significant amount, it is likely that IL-1beta elicits CeA cell recruitment by means of activation of afferents to the CeA. However, although many studies have investigated the origins of afferent inputs to the CeA, we do not know which of these also respond to IL-1beta. Therefore, to identify candidate neurons responsible for the recruitment of CeA cells by an immune challenge, we iontophoretically deposited a retrograde tracer, cholera toxin b-subunit (CTb), into the CeA of rats 7 days before systemic delivery of IL-1beta (1 mug/kg, i.a.). By using combined immunohistochemistry, we then quantified the number of Fos-positive CTb cells in six major regions known to innervate the CeA. These included the medial prefrontal cortex, paraventricular thalamus (PVT), ventral tegmental area, parabrachial nucleus (PB), nucleus tractus solitarius, and ventrolateral medulla. Our results show that after deposit of CTb into the CeA, the majority of double-labeled cells were located in the PB and the PVT, suggesting that CeA cell activation by systemic IL-1beta is likely to arise predominantly from cell bodies located in these regions. These findings may have significant implications in determining the central pathways involved in generating acute central responses to a systemic immune challenge. J. Comp. Neurol. 452:288-296, 2002. (C) 2002 Wiley-Liss, Inc.

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The mononuclear phagocyte system (MPS) was defined as a family of cells comprising bone marrow progenitors, blood monocytes, and tissue macrophages. In this review, we briefly consider markers for cells of this lineage in the mouse, especially the F4/80 surface antigen and the receptor for macrophage colony-stimulating factor. The concept of the MPS is challenged by evidence that there is a separate embryonic phagocyte lineage, the blurring of the boundaries between macrophages and other cells types arising from phenotypic plasticity and transdifferentiation, and evidence of local renewal of tissue macrophage populations as opposed to monocyte recruitment. Nevertheless, there is a unity to cells of the MPS suggested by their location, morphology, and shared markers. We discuss the origins of macrophage heterogeneity and argue that macrophages and antigen-representing dendritic cells are closely related and part of the MPS.

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Flavonoids, phenolic acids and abscisic acid of Australian and New Zealand Leptospermum honeys were analyzed by HPLC. Fifteen flavonoids were isolated in Australian jelly bush honey (Leptospermum polygalifolium), with an average content of 2.22 mg/100 g honey. Myricetin (3,5,7,3',4',5'-hexahydroxyflavone), luteolin (5,7,3',4'-tetrahydroxyflavone) and tricetin (5,7,3',4',5'-pentahydroxyflavone) were the main flavonoids identified. The mean content of total phenolic acids in jelly bush honey was 5.14 mg/100 g honey, with gallic and coumaric acids as the potential phenolic acids. Abscisic acid was quantified as twice the amount (11.6 mg/100 g honey) of the phenolic acids in this honey. The flavonoid profile mainly consisted of quercetin (3,5,7,3',4'-pentahydroxyflavone), isorhamnetin (3,5,7,4'-tetrahydroxyflavone 3'-methyl ethyl), chrysin (5,7-dihydroxyflavone), luteolin and an unknown flavanone in New Zealand manuka (Leptospermum scoparium) honey with an average content of total flavonoids of 3.06 mg/100 g honey. The content of total phenolic acids was up to 14.0 mg/100 g honey, with gallic acid as the main component. A substantial quantity (32.8 mg/100 g honey) of abscisic acid was present in manuka honey. These results showed that flavonoids and phenolic acids could be used for authenticating honey floral origins, and abscisic acid may aid in this authentication. (C) 2002 Published by Elsevier Science Ltd.

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O objetivo deste artigo ?? expor e explicar um momento espec??fico da evolu????o pol??tico institucional brasileira. S??o explorados os conflitos que est??o na origem da escolha e a implementa????o de uma nova ordem pol??tico-administrativa no p??s-1930. S??o examinadas as origens, a concep????o e os objetivos que guiaram a inven????o de um aparelho burocr??tico que, juntamente com o interventor federal, n??o s?? controlou as elites pol??ticas regionais, mas tamb??m contribuiu para a organiza????o do poder do Estado em bases nacionais, cooperando para viabilizar a capacidade estatal: os Departamentos Administrativos. Analiso o contexto pol??tico, os antecedentes legais e as inova????es institucionais do decreto-lei n?? 1202/39, a fim de responder a duas quest??es bem espec??ficas: por que e com que objetivo essa lei sobre a administra????o dos estados e dos munic??pios foi criada durante o Estado Novo?

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Esta disserta????o discute o curso de forma????o dos Especialistas em Pol??ticas P??blicas e Gest??o Governamental - EPPGG. Para tanto, foi feito um breve levantamento hist??rico da origem dessa carreira, evidenciando as dificuldades que surgiram em sua implanta????o na burocracia da administra????o p??blica federal. O texto descreve o processo de sele????o e forma????o das turmas de EPPGG, dando maior aten????o ?? primeira turma, que se deu num contexto pol??tico espec??fico e ?? quinta turma, que foi o objeto do estudo de caso. Buscou-se fugir/escapar dos estudos puramente normativos ou inteiramente formalizantes. Desse modo, a an??lise privilegiou a reflex??o sobre as rela????es sociais cotidianas estabelecidas durante o curso, procurando desvelar conflitos e dilemas que demonstram fissuras internas da pr??pria carreira e da institui????o ENAP.

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Este estudo foi elaborado a partir da proposta de fortalecimento das relações comunitárias entre a Universidade Federal do Espírito Santo e as comunidades jongueiras e caxambuzeiras. Destina-se a apresentar a pesquisa realizada em territórios negros sob a inspiração do Jongo e do Caxambu, reconhecidos como Patrimônio Imaterial do Brasil pelo Instituto do Patrimônio Histórico e Artístico Nacional (Iphan). A pesquisa foi desenvolvida no norte do Estado do Espírito Santo e tem como recurso analítico e conceitual estudos sobre etnicidade no campo da educação. Sua proposta é ampliar e constituir-se como base para a implementação da Lei nº. 10.639/2003, considerando a descrição das categorias religiosidade, territorialidade, memórias, cultura negra, cultura popular e tradição, com base nas narrativas dos sujeitos. Relaciona as práticas culturais do jongo e do caxambu como elementos importantes para a reconstrução da história do negro no Sudeste brasileiro. O tema de investigação foi construído sob a inspiração teórica dos estudos culturais referenciados em Stuart Hall (2008), Canclini (1997), Santos (2008, 2009), Certeau (2005) e na produção simbólica das interpretações sociais, das fronteiras étnicas para descrever as diferenças percebidas pelos sujeitos. Trabalhou-se basicamente propondo as múltiplas interpretações a partir do vivido. O estudo reforça a importância das africanidades na formação de professores e a discussão do Patrimônio Imaterial do Jongo como possibilidades de saberes-fazeres no campo do currículo escolar. Os caminhos da pesquisa partem de uma base etnográfica, conjugando a metodologia da história oral temática com a pesquisa participante e a pesquisa ação, interligando as memórias dos sujeitos, suas narrativas e vivências ao fazer pedagógico no cotidiano das comunidades. Ressalta a relação intercultural e territorial que identifica jongueiros e caxambuzeiros. Os resultados da pesquisa descrevem as condições dessas práticas, da visibilidade das políticas culturais, da produção das identidades jongueiras no norte do Estado do Espírito Santo, sob o ponto de vista dos sujeitos elencados.

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A presente dissertação investiga o atual estágio de manutenção das variedades dialetais da Itália setentrional no município de Santa Teresa, localizado na região serrana do Espírito Santo. Este trabalho se justifica porque, após 141 anos da chegada dos primeiros italianos a esse município, ainda não existem estudos que abordem questões relacionadas aos dialetos italianos da localidade. Considerando esse cenário, o objetivo deste estudo é oferecer um panorama da situação bilíngue português-dialeto italiano no município, com a identificação das áreas de maior ou menor uso do dialeto e ainda os fatores determinantes para a escolha linguística, os domínios de uso e as atitudes linguísticas dos falantes. Um segundo objetivo do estudo foi documentar algumas tradições orais italianas ainda presentes em Santa Teresa. Os dados foram coletados por meio de observação participante, questionário sociolinguístico e 146 entrevistas semiestruturadas, nas quais os informantes foram divididos por local de residência (zona rural e urbana) e em três faixas etárias (entre 08-30 anos, 31-60 e acima de 60 anos de idade). Os resultados encontrados revelam que o termo taliàn, que significa italiano nos dialetos da Itália setentrional (cf. BOERIO, 1856; RICCI, 1906 etc.), é usado pela maior parte dos falantes da faixa etária acima de 60 anos das zonas rural e urbana. Analisando diacronicamente o processo de uso do dialeto italiano através dos diferentes domínios, no período da infância dos informantes e na atualidade, é possível verificar a perda do dialeto no trajeto de vida dos falantes das faixas etárias de 31-60 anos e dos acima de 60 anos. Entre os informantes da faixa etária de 08-30 anos, verifica-se um quase completo monolinguismo português. Entre os informantes da faixa etária de 31-60 anos, o uso do dialeto italiano é fortemente influenciado pela idade do interlocutor: usam-no mais com seus avós do que com seus pais, e com seus pais mais do que com seus irmãos. Entretanto, nenhum informante desta faixa etária relatou usar o dialeto italiano com os filhos. Em resumo, o uso do dialeto italiano somente entre os membros mais idosos indica o processo de sua substituição pelo português e aponta que sua transmissão às gerações mais jovens está seriamente ameaçada. A análise das atitudes linguísticas dos informantes acima de 60 anos permitiu constatar o desprestígio e o preconceito em relação ao uso do dialeto no período da infância dos informantes. Por outro lado, os relatos em relação ao uso do dialeto na atualidade referem-se à associação da língua e da cultura de origem italiana com elementos positivos; à vontade explícita de manutenção do dialeto pelos adultos e idosos, à recuperação da língua de imigração pelos informantes de 08-30 anos. Aliás, entre os mais jovens, percebe-se uma tentativa de retorno às origens, de valorização da cultura e da língua dos antepassados.

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This work presents an analysis of the cultural and artistic field, positively compromised with social and political questions. The authors start with the categorization of the idea of culture and move to vindication art movements. These movements, which followed the first vanguards and worked from the compromise with “otherness”, are at the origin of the contemporary denomination of political art. In this context, the authors approach the origins of activist art, referring to issues of gender, multiculturalism, globalization, and poverty. The different forms of presenting content are also an object of analysis: from art tradition to the contamination of daily life, from local to global, from street contact to digital.