78 research outputs found
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Who Pays for Long-Term Services and Supports? A Fact Sheet
This report provides information on who the primary long-term services and supports (LTSS) payers are and how much they spend
Catalog of selected heavy duty transport energy management models
A catalog of energy management models for heavy duty transport systems powered by diesel engines is presented. The catalog results from a literature survey, supplemented by telephone interviews and mailed questionnaires to discover the major computer models currently used in the transportation industry in the following categories: heavy duty transport systems, which consist of highway (vehicle simulation), marine (ship simulation), rail (locomotive simulation), and pipeline (pumping station simulation); and heavy duty diesel engines, which involve models that match the intake/exhaust system to the engine, fuel efficiency, emissions, combustion chamber shape, fuel injection system, heat transfer, intake/exhaust system, operating performance, and waste heat utilization devices, i.e., turbocharger, bottoming cycle
A construção do conhecimento ortográfico no contexto das interações adulto-criança
Partindo do problema do desempenho insuficiente nas habilidades de escrita de estudantes brasileiros, o artigo tem o objetivo de apresentar uma pesquisa sobre o papel da interação entre adulto e criança na construção do conhecimento ortográfico. Para tanto, recupera parte de um estudo de caso longitudinal em curso, realizado com alunos de uma escola privada em Santos/SP, em cinco etapas entre o 2º e o 4º ano do Ensino Fundamental (período em que o escrever corretamente passa a ser um foco especial de conquista cognitiva e, consequentemente, de ensino). Valendo-se do referencial teórico dos estudos psicogenéticos e histórico-culturais (a concepção das crianças como sujeitos ativos e protagonistas da aprendizagem; a língua como prática social e a interação como favorecimento da aprendizagem), o estudo centrou-se na problematização, feita de modo interativo, sobre as formas de escrever. Realizada a partir de dois eixos de atividade (ditado de palavras e reescrita de contos), a coleta de dados visou apreender a compreensão das estratégias infantis ou das reflexões empreendidas na busca de referências para a correção da escrita, chegando, assim, a quatro categorias: a escrita validada pela pauta sonora, a validação da escrita com base em alguém mais experiente (um “interlocutor autorizado”), o apoio na imagem visual da palavra e, finalmente, a evocação da norma ortográfica. Embora essas categorias estejam sempre presentes nos diferentes estágios de escolaridade (e de conhecimento), a análise quanti-qualitativa dos dados evidenciou o predomínio de umas sobre as outras que, em movimentos ascendentes e descendentes, marcam um percurso de crescente autonomia e consciência metalinguística. A partir da compreensão sobre os processos cognitivos do conhecimento ortográfico – a variedade das estratégias de escrita ou de validação da escrita e caminhos de progressão –, é possível vislumbrar algumas implicações pedagógicas que subsidiam a revisão de práticas pedagógicas
Antimicrobial resistance profiles of Shiga toxin-producing Escherichia coli O157 and Non-O157 recovered from domestic farm animals in rural communities in Northwestern Mexico
Drug resistance, AmpC-β-lactamase and extended-spectrum β-lactamase-producing Enterobacteriaceae isolated from fish and shrimp
Optic chiasm in the species of order Clupeiformes, family Clupeidae: Optic chiasm of Spratelloides gracilis shows an opposite laterality to that of Etrumeus teres
In most teleost fishes, the optic nerves decussate completely as they project to the mesencephalic region. Examination of the decussation pattern of 25 species from 11 different orders in Pisces revealed that each species shows a specific chiasmic type. In 11 species out of the 25, laterality of the chiasmic pattern was not determined; in half of the individuals examined, the left optic nerve ran dorsally to the right optic nerve, while in the other half, the right optic nerve was dorsal. In eight other species the optic nerves from both eyes branched into several bundles at the chiasmic point, and intercalated to form a complicated decussation pattern. In the present study we report our findings that Spratelloides gracilis, of the order Clupeiformes, family Clupeidae, shows a particular laterality of decussation: the left optic nerve ran dorsally to the right (n = 200/202). In contrast, Etrumeus teres, of the same order and family, had a strong preference of the opposite (complementary) chiasmic pattern to that of S. gracilis (n = 59/59), revealing that these two species display opposite left–right optic chiasm patterning. As far as we investigated, other species of Clupeiformes have not shown left–right preference in the decussation pattern. We conclude that the opposite laterality of the optic chiasms of these two closely related species, S. gracilis and E. teres, enables investigation of species-specific laterality in fishes of symmetric shapes
Oligodendrocytes: biology and pathology
Oligodendrocytes are the myelinating cells of the central nervous system (CNS). They are the end product of a cell lineage which has to undergo a complex and precisely timed program of proliferation, migration, differentiation, and myelination to finally produce the insulating sheath of axons. Due to this complex differentiation program, and due to their unique metabolism/physiology, oligodendrocytes count among the most vulnerable cells of the CNS. In this review, we first describe the different steps eventually culminating in the formation of mature oligodendrocytes and myelin sheaths, as they were revealed by studies in rodents. We will then show differences and similarities of human oligodendrocyte development. Finally, we will lay out the different pathways leading to oligodendrocyte and myelin loss in human CNS diseases, and we will reveal the different principles leading to the restoration of myelin sheaths or to a failure to do so
Ensino de língua materna: dificuldades e necessidades formativas apontadas por professores na Educação Fundamental
Neuregulin and BDNF Induce a Switch to NMDA Receptor-Dependent Myelination by Oligodendrocytes
<div><p>Myelination is essential for rapid impulse conduction in the CNS, but what determines whether an individual axon becomes myelinated remains unknown. Here we show, using a myelinating coculture system, that there are two distinct modes of myelination, one that is independent of neuronal activity and glutamate release and another that depends on neuronal action potentials releasing glutamate to activate NMDA receptors on oligodendrocyte lineage cells. Neuregulin switches oligodendrocytes from the activity-independent to the activity-dependent mode of myelination by increasing NMDA receptor currents in oligodendrocyte lineage cells 6-fold. With neuregulin present myelination is accelerated and increased, and NMDA receptor block reduces myelination to far below its level without neuregulin. Thus, a neuregulin-controlled switch enhances the myelination of active axons. <i>In vivo</i>, we demonstrate that remyelination after white matter damage is NMDA receptor-dependent. These data resolve controversies over the signalling regulating myelination and suggest novel roles for neuregulin in schizophrenia and in remyelination after white matter damage.</p></div
Surface ecophysiological behavior across vegetation and moisture gradients in tropical South America
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