604 resultados para CAA


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Deposition of PrP amyloid in cerebral vessels in conjunction with neurofibrillary lesions is the neuropathologic hallmark of the dementia associated with a stop mutation at codon 145 of PRNP, the gene encoding the prion protein (PrP). In this disorder, the vascular amyloid in tissue sections and the approximately 7.5-kDa fragment extracted from amyloid are labeled by antibodies to epitopes located in the PrP sequence including amino acids 90-147. Amyloid-laden vessels are also labeled by antibodies against the C terminus, suggesting that PrP from the normal allele is involved in the pathologic process. Abundant neurofibrillary lesions are present in the cerebral gray matter. They are composed of paired helical filaments, are labeled with antibodies that recognize multiple phosphorylation sites in tau protein, and are similar to those observed in Alzheimer disease. A PrP cerebral amyloid angiopathy has not been reported in diseases caused by PRNP mutations or in human transmissible spongiform encephalopathies; we propose to name this phenotype PrP cerebral amyloid angiopathy (PrP-CAA).

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Mouse skin tumors contain activated c-H-ras oncogenes, often caused by point mutations at codons 12 and 13 in exon 1 and codons 59 and 61 in exon 2. Mutagenesis by the noncoding apurinic sites can produce G-->T and A-->T transversions by DNA misreplication with more frequent insertion of deoxyadenosine opposite the apurinic site. Papillomas were induced in mouse skin by several aromatic hydrocarbons, and mutations in the c-H-ras gene were determined to elucidate the relationship among DNA adducts, apurinic sites, and ras oncogene mutations. Dibenzo[a,l]pyrene (DB[a,l]P), DB[a,l]P-11,12-dihydrodiol, anti-DB[a,l]P-11,12-diol-13,14-epoxide, DB[a,l]P-8,9-dihydrodiol, 7,12-dimethylbenz[a]anthracene (DMBA), and 1,2,3,4-tetrahydro-DMBA consistently induced a CAA-->CTA mutation in codon 61 of the c-H-ras oncogene. Benzo[a]pyrene induced a GGC-->GTC mutation in codon 13 in 54% of tumors and a CAA-->CTA mutation in codon 61 in 15%. The pattern of mutations induced by each hydrocarbon correlated with its profile of DNA adducts. For example, both DB[a,l]P and DMBA primarily form DNA adducts at the N-3 and/or N-7 of deoxyadenosine that are lost from the DNA by depurination, generating apurinic sites. Thus, these results support the hypothesis that misreplication of unrepaired apurinic sites generated by loss of hydrocarbon-DNA adducts is responsible for transforming mutations leading to papillomas in mouse skin.

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RESUMO Simulações de aeroacústica computacional demandam uma quantidade considerável de tempo, o que torna complicada a realização de estudos paramétricos. O presente trabalho propõe uma metodologia viável para otimização aeroacústica. Através da análise numérica utilizando dinâmica dos fluidos computacional, foi estudada a aplicação de uma placa separadora desacoplada como método de controle passivo da esteira turbulenta de um cilindro e avaliou-se a irradiação de ruído causado pela interação do escoamento com ambos os corpos, empregando ferramentas de aeroacústica computacional baseadas no método de Ffowcs-Williams e Hawkings. Algumas abordagens distintas de metodologias de otimização de projeto foram aplicadas neste problema, com o objetivo de chegar a uma configuração otimizada que permita a redução do nível sonoro ao longe. Assim, utilizando uma ferramenta de otimização multidisciplinar, pode-se avaliar a capacidade de modelos heurísticos e a grande vantagem do emprego de algoritmos baseados em método de superfície de resposta quando aplicados em um problema não linear, pois requerem a avaliação de um menor número de alternativas para se obter um ponto ótimo. Além disso, foi possível identificar e agrupar os resultados em 5 clusters baseados em seus parâmetros geométricos, nível de pressão sonora global e o valor quadrático médio do coeficiente de arrasto, confirmando a eficiência da aplicação de placas separadoras longas desacopladas posicionadas próximas ao cilindro na estabilização da esteira turbulenta, enquanto que o posicionamento de placas acima de um espaçamento crítico aumentou o nível de pressão acústica irradiado devido à formação de vórtices no espaço entre o cilindro e a placa separadora.

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Com o objetivo de comparar em termos de paisagem, a vegetação florestal nativa com os fragmentos da vegetação remanescente na bacia hidrográfica do Rio Canoas, situada na divisa dos Estados de São Paulo (à Nordeste) e Minas Gerais (à Centro-Oeste), busca-se dar subsídios aos atores locais para trabalhar políticas públicas com vistas à sustentabilidade do uso dos recursos naturais na região. Foram mapeados sete tipos de vegetação, com destaque para o cerrado e a floresta estacional semidecidual. O método do estudo é exploratório, realizado em fontes secundárias, pesquisa bibliográfica e documental, baseado no estudo de mapas e suas simulações, dados do IBGE, Embrapa, Ministério do Meio Ambiente e trabalhos de autores, como: Cogo (1987), Coutinho (2000) e Bozini (2005). Observou-se que a bacia hidrográfica objeto em estudo é degradada historicamente pelos diversos usos e ocupações do solo e sua maior parte ainda está sujeita à um elevado nível de perturbação, seja pela pecuária, ou mesmo pelas plantações de laranja, milho, eucalipto, cana-de-açúcar e, principalmente, pela cultura do café.

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Excavations were carried out in a Late Palaeolithic site in the community of Bad Buchau-Kappel between 2003 and 2007. Archaeological investigations covered a total of more than 200 m**2. This site is the product of what likely were multiple occupations that occurred during the Late Glacial on the Federsee shore in this location. The site is situated on a mineral ridge that projected into the former Late Glacial lake Federsee. This beach ridge consists of deposits of fine to coarse gravel and sand and was surrounded by open water, except for a connection to the solid shore on the south. A lagoon lay between the hook-shaped ridge and the shore of the Federsee. This exposed location provided optimal access to the water of the lake. In addition, the small lagoon may have served as a natural harbor for landing boats or canoes. Sedimentological and palynological investigations document the dynamic history of the location between 14,500 and 11,600 years before present (cal BP). Evidence of the deposition of sands, gravels and muds since the Bølling Interstadial is provided by stratigraphic and palynological analyses. The major occupation occurred in the second half of the Younger Dryas period. Most of the finds were located on or in the sediments of the ridge; fewer finds occurred in the surrounding mud, which was also deposited during the Younger Dryas. Direct dates on some bone fragments, however, demonstrate that intermittent sporadic occupations also took place during the two millennia of the Meiendorf, Bølling, and Allerød Interstadials. These bones were reworked during the Younger Dryas and redeposited in the mud. A 14C date from one bone of 11,600 years ago (cal BP) places the Late Palaeolithic occupation of the ridge at the very end of the Younger Dryas, which is in agreement with stratigraphic observations. Stone artifacts, numbering 3,281, comprise the majority of finds from the site. These include typical artifacts of the Late Palaeolithic, such as backed points, short scrapers, and small burins. There are no bipointes or Malaurie-Points, which is in accord with the absolute date of the occupation. A majority of the artifacts are made from a brown chert that is obtainable a few kilometers north of the site in sediments of the Graupensandrinne. Other raw materials include red and green radiolarite that occur in the fluvioglacial gravels of Oberschwaben, as well as quartzite and lydite. The only non-local material present is a few artifacts of tabular chert from the region near Kelheim in Bavaria. A unique find consists of two fragments of a double-barbed harpoon made of red deer antler, which was found in the Younger Dryas mud. It is likely, but not certain, that this find belongs to the same assemblage as the numerous stone artifacts. Although not numerous, animal bones were also found in the excavations. Most of them lay in sediments of the Younger Dryas, but several 14C dates place some of these bones in earlier periods, including the Meiendorf, Bølling, and Allerød Interstadials. These bones were reworked by water and redeposited in mud sediments during the Younger Dryas. As a result, it is difficult to attribute individual bones to particular chronological positions without exact dates. Species that could be identified include wild horse (Equus spec.), moose or elk (Alces alces), red deer (Cervus elaphus), roe deer (Capreolus capreolus), aurochs or bison (Bos spec.), wild boar (Sus scrofa), as well as birds and fish, including pike (Esox Lucius).

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Contiene: Tomo 1, A-AL. Tomo 2, AL-ARZ. Tomo 3, ARR-BAR. Tomo 4 BAR-BUZ. Tomo 5, CAA-CAR. Tomo 6, CAS-COR. Tomo 7, COR-EZT. Tomo 8, FAB-GUA. Tomo 9, GUA-JUZ. Tomo 10, LAB-MAD. Tomo 11, MAD-MUZ. Tomo 12, NAB-PEZ. Tomo 13, PIA-SAZ, Tomo 14, SEA-TOL. Tomo 15, TOL-VET. Tomo 16, VIA-ZUZ.

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La vinculación productiva de los diferentes espacios agrícolas regionales argentinos al mercado mundial, durante la segunda mitad del siglo XIX, fue llevada adelante mediante diferentes políticas públicas en torno a la propiedad de los bienes, la gestión del territorio y los recursos. Y cada una de estas políticas impactaron en la relación entre las comunidades locales y los poderes provinciales. ;Con respecto a la gestión de los recursos hídricos, un tema aún poco abordado por la historiografía concentrada en las grandes llanuras, en este trabajo nos proponemos estudiar los modos en que fue cambiando el uso del agua para beneficiar a la agricultura en las provincias de Santiago del Estero y Buenos Aires, entre mediados de la década de 1870 y 1900. En la primera, estudiaremos la forma en que la cuenca del río Dulce se verá atravesada por canales principales que, tomando agua del curso principal, la derivarán a través de una red de canales subsidiarios e hijuelas, que trazaron una compleja red hídrica principalmente en el ejido urbano de la ciudad de Santiago del Estero para desarrollar cultivos novedosos para la provincia como la vid y la caña de azúcar, dando lugar a una serie de pequeñas villas. En la segunda observaremos cómo la demanda de grandes propietarios de las tierras de reciente ocupación criolla del suroeste provincial posibilitaba la construcción de canales de desvío de ríos y arroyos para regar sus campos, como así también la provincia desarrolló una serie de estudios de canalización para generar colonias agrícolas. ;Nos proponemos avanzar sobre las relaciones entre las tramas políticas y económicas y las confluencias de intereses públicos y particulares, que hicieron posible que los gobiernos provinciales tomaran bajo su responsabilidad la provisión de agua para el desarrollo de la agricultura; identificaremos las instituciones involucradas en el gerenciamiento del aprovisionamiento de agua y las cuestiones técnicas que se pusieron en juego, las dificultades que debían sortearse y los límites que planteaba el esquema de desarrollo. Por último, y teniendo en cuenta que para la administración del agua de riego el gobierno de Santiago del Estero organizó un esquema sindical centralizado con apoyaturas departamentales, nos adentraremos en la historia del primer espacio democratizador en la provincia con instituciones cuyas autoridades eran elegidas por los propios regantes propietarios de tierras y renovadas anualmente. Esto contrasta con el modelo bonaerense en el que la iniciativa privada de los grandes propietarios tuvo respuesta individuales a través de decretos y disposiciones ad hoc.

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La vinculación productiva de los diferentes espacios agrícolas regionales argentinos al mercado mundial, durante la segunda mitad del siglo XIX, fue llevada adelante mediante diferentes políticas públicas en torno a la propiedad de los bienes, la gestión del territorio y los recursos. Y cada una de estas políticas impactaron en la relación entre las comunidades locales y los poderes provinciales. ;Con respecto a la gestión de los recursos hídricos, un tema aún poco abordado por la historiografía concentrada en las grandes llanuras, en este trabajo nos proponemos estudiar los modos en que fue cambiando el uso del agua para beneficiar a la agricultura en las provincias de Santiago del Estero y Buenos Aires, entre mediados de la década de 1870 y 1900. En la primera, estudiaremos la forma en que la cuenca del río Dulce se verá atravesada por canales principales que, tomando agua del curso principal, la derivarán a través de una red de canales subsidiarios e hijuelas, que trazaron una compleja red hídrica principalmente en el ejido urbano de la ciudad de Santiago del Estero para desarrollar cultivos novedosos para la provincia como la vid y la caña de azúcar, dando lugar a una serie de pequeñas villas. En la segunda observaremos cómo la demanda de grandes propietarios de las tierras de reciente ocupación criolla del suroeste provincial posibilitaba la construcción de canales de desvío de ríos y arroyos para regar sus campos, como así también la provincia desarrolló una serie de estudios de canalización para generar colonias agrícolas. ;Nos proponemos avanzar sobre las relaciones entre las tramas políticas y económicas y las confluencias de intereses públicos y particulares, que hicieron posible que los gobiernos provinciales tomaran bajo su responsabilidad la provisión de agua para el desarrollo de la agricultura; identificaremos las instituciones involucradas en el gerenciamiento del aprovisionamiento de agua y las cuestiones técnicas que se pusieron en juego, las dificultades que debían sortearse y los límites que planteaba el esquema de desarrollo. Por último, y teniendo en cuenta que para la administración del agua de riego el gobierno de Santiago del Estero organizó un esquema sindical centralizado con apoyaturas departamentales, nos adentraremos en la historia del primer espacio democratizador en la provincia con instituciones cuyas autoridades eran elegidas por los propios regantes propietarios de tierras y renovadas anualmente. Esto contrasta con el modelo bonaerense en el que la iniciativa privada de los grandes propietarios tuvo respuesta individuales a través de decretos y disposiciones ad hoc.

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La vinculación productiva de los diferentes espacios agrícolas regionales argentinos al mercado mundial, durante la segunda mitad del siglo XIX, fue llevada adelante mediante diferentes políticas públicas en torno a la propiedad de los bienes, la gestión del territorio y los recursos. Y cada una de estas políticas impactaron en la relación entre las comunidades locales y los poderes provinciales. ;Con respecto a la gestión de los recursos hídricos, un tema aún poco abordado por la historiografía concentrada en las grandes llanuras, en este trabajo nos proponemos estudiar los modos en que fue cambiando el uso del agua para beneficiar a la agricultura en las provincias de Santiago del Estero y Buenos Aires, entre mediados de la década de 1870 y 1900. En la primera, estudiaremos la forma en que la cuenca del río Dulce se verá atravesada por canales principales que, tomando agua del curso principal, la derivarán a través de una red de canales subsidiarios e hijuelas, que trazaron una compleja red hídrica principalmente en el ejido urbano de la ciudad de Santiago del Estero para desarrollar cultivos novedosos para la provincia como la vid y la caña de azúcar, dando lugar a una serie de pequeñas villas. En la segunda observaremos cómo la demanda de grandes propietarios de las tierras de reciente ocupación criolla del suroeste provincial posibilitaba la construcción de canales de desvío de ríos y arroyos para regar sus campos, como así también la provincia desarrolló una serie de estudios de canalización para generar colonias agrícolas. ;Nos proponemos avanzar sobre las relaciones entre las tramas políticas y económicas y las confluencias de intereses públicos y particulares, que hicieron posible que los gobiernos provinciales tomaran bajo su responsabilidad la provisión de agua para el desarrollo de la agricultura; identificaremos las instituciones involucradas en el gerenciamiento del aprovisionamiento de agua y las cuestiones técnicas que se pusieron en juego, las dificultades que debían sortearse y los límites que planteaba el esquema de desarrollo. Por último, y teniendo en cuenta que para la administración del agua de riego el gobierno de Santiago del Estero organizó un esquema sindical centralizado con apoyaturas departamentales, nos adentraremos en la historia del primer espacio democratizador en la provincia con instituciones cuyas autoridades eran elegidas por los propios regantes propietarios de tierras y renovadas anualmente. Esto contrasta con el modelo bonaerense en el que la iniciativa privada de los grandes propietarios tuvo respuesta individuales a través de decretos y disposiciones ad hoc.

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Field surveys of egg parasitoids of the diamondback moth, Plutella xylostella, were conducted at Redlands and Gatton, south-east Queensland. Eggs of P. xylostella were present all year round in both localities, and parasitized eggs were consistently found between late spring and early winter. Percent parasitism in the range 30-75% was recorded on many occasions, although rates less than 10% were more common. The major parasitoids included Trichogrammatoidea bactrae Nagaraja and Trichogramma pretiosum Riley. Laboratory evaluation showed that the T. pretiosum from Gatton has a high capacity to parasitize P. xylostella eggs under suitable conditions. This study represents the first record of egg parasitoids of P. xylostella from Australia.

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A culster analysis was performed on 78 cases of Alzheimer's disease (AD) to identify possible pathological subtypes of the disease. Data on 47 neuropathological variables, inculding features of the gross brain and the density and distribution of senile plaques (SP) and neurofibrillary tangles (NFT) were used to describe each case. Cluster analysis is a multivariate statistical method which combines together in groups, AD cases with the most similar neuropathological characteristics. The majority of cases (83%) were clustered into five such groups. The analysis suggested that an initial division of the 78 cases could be made into two major groups: (1) a large group (68%) in which the distribution of SP and NFT was restricted to a relatively small number of brain regions, and (2) a smaller group (15%) in which the lesions were more widely disseminated throughout the neocortex. Each of these groups could be subdivided on the degree of capillary amyloid angiopathy (CAA) present. In addition, those cases with a restricted development of SP/NFT and CAA could be divided further into an early and a late onset form. Familial AD cases did not cluster as a separate group but were either distributed between four of the five groups or were cases with unique combinations of pathological features not closely related to any of the groups. It was concluded that multivariate statistical methods may be of value in the classification of AD into subtypes. © 1994 Springer-Verlag.

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The research was instigated by the Civil Aviation Authority (CAA) to examine the implications for air traffic controllers' (ATCO) job satisfaction of the possible introduction of systems incorporating computer-assisted decision making. Additional research objectives were to assess the possible costs of reductions in ATCO job satisfaction, and to recommend appropriate task allocation between ATCOs and computer for future systems design (Chapter 1). Following a review of the literature (Chapter 2) it is argued that existing approaches to systems and job design do not allow for a sufficiently early consideration of employee needs and satisfactions in the design of complex systems. The present research develops a methodology for assessing affective reactions to an existing system as a basis for making reommendations for future systems design (Chapter 3). The method required analysis of job content using two techniques: (a) task analysis (Chapter 4.1) and (b) the Job Diagnostic Survey (JDS). ATCOs' affective reactions to the several operational positions on which they work were investigated at three levels of detail: (a) Reactions to positions, obtained by ranking techniques (Chapter 4.2); (b) Reactions to job characteristics, obtained by use of JDS (Chapter 4.3); and (c) Reactions to tasks, obtained by use of Repertory Grid technique (Chapter 4.4). The conclusion is drawn that ATCOs' motivation and satisfaction is greatly dependent on the presence of challenge, often through tasks requiring the use of decision making and other cognitive skills. Results suggest that the introduction of systems incorporating computer-assisted decision making might result in financial penalties for the CAA and significant reductions in job satisfaction for ATCOs. General recommendations are made for allocation of tasks in future systems design (Chapter 5).