990 resultados para 172-1064
Resumo:
ix Ocean Drilling Program (ODP) sites, in the Northwest Atlantic have been used to investigate kinematic and chemical changes in the "Western Boundary Undercurrent" (WBUC) during the development of full glacial conditions across the Marine Isotope Stage 5a/4 boundary (~70,000 years ago). Sortable silt mean grain size(sort s) measurements are employed to examine changes in near bottom flow speeds, together with carbon isotopes measured in benthic foraminifera and % planktic foraminiferal fragmentation as proxies for changes in water-mass chemistry. A depth transect of cores, spanning 1.8-4.6 km depth, allows changes in both the strength and depth of the WBUC to be constrained across millennial scale events. Sort s measurements reveal that the flow speed structure of the WBUC during warm intervals ("interstadials") was comparable to modern (Holocene) conditions. However, significant differences are observed during cold intervals, with higher relative flow speeds inferred for the shallow component of the WBUC (~2 km depth) during all cold "stadial" intervals (including Heinrich Stadial 6), and a substantial weakening of the deep component (~3-4 km) during full glacial conditions. Our results therefore reveal that the onset of full glacial conditions was associated with a regime shift to a shallower mode of circulation (involving Glacial North Atlantic Intermediate Water) that was quantitatively distinct from preceding cold stadial events. Furthermore, our chemical proxy data show that the physical response of the WBUC during the last glacial inception was probably coupled to basin-wide changes in the water-mass composition of the deep Northwest Atlantic.
Resumo:
Rezension von: Ludwig Liegle: Frühpädagogik. Erziehung und Bildung kleiner Kinder. Ein dialogischer Ansatz. Stuttgart: Kohlhammer 2013 (172 S.; ISBN 978-3-17-022480-3)
Resumo:
Este proyecto se origina en el interés de analizar las estrategias actuales de promoción de productos farmacéuticos, en el marco del debate sobre el efecto persuasivo o informativo que la publicidad directa tiene sobre los consumidores. El objetivo es determinar el efecto de las estrategias de promoción directa para consumidores (Direct to Consumer Advertising [DTCA]) sobre el comportamiento de compra de pacientes y las prescripciones que formulan los médicos en el mercado de productos bajo receta en Estados Unidos. Para tal fin se propuso realizar una monografía que incluyera una revisión de literatura de carácter argumentativo, consultando información de nivel secundario en bases de datos científicas cuyos contenidos obedecieran a criterios metodológicos determinados por la naturaleza argumentativa del estudio. Adicionalmente, se analizó el debate sobre estos anuncios a la luz de dos estudios realizados a pacientes con cáncer de seno, próstata y colon, liderados por el Pennsylvania Cancer Registry con los productos biofarmacéuticos Avodart® y Flomax®. Finalmente, la investigación se fundamentó en la relación del mercado farmacéutico en Estados Unidos con cada uno de los agentes que interactúan en él; consumidores, médicos prescriptores y empresas farmacéuticas, así como el valor que estos comparten través de dichas interacciones. Se concluye que el comportamiento de compra de los consumidores está determinado por la naturaleza de la patología que padecen y el comportamiento de los profesionales que prescriben a sus pacientes se ve influenciado por los anuncios DTCA.
Resumo:
Brucite [Mg(OH)2] microbialites occur in vacated interseptal spaces of living scleractinian coral colonies (Acropora, Pocillopora, Porites) from subtidal and intertidal settings in the Great Barrier Reef, Australia, and subtidal Montastraea from the Florida Keys, United States. Brucite encrusts microbial filaments of endobionts (i.e., fungi, green algae, cyanobacteria) growing under organic biofilms; the brucite distribution is patchy both within interseptal spaces and within coralla. Although brucite is undersaturated in seawater, its precipitation was apparently induced in the corals by lowered pCO2 and increased pH within microenvironments protected by microbial biofilms. The occurrence of brucite in shallow-marine settings highlights the importance of microenvironments in the formation and early diagenesis of marine carbonates. Significantly, the brucite precipitates discovered in microenvironments in these corals show that early diagenetic products do not necessarily reflect ambient seawater chemistry. Errors in environmental interpretation may arise where unidentified precipitates occur in microenvironments in skeletal carbonates that are subsequently utilized as geochemical seawater proxies.
Resumo:
This paper first describes a new three-year, longitudinal project that is implementing engineering education in three middle schools in Australia (grade levels 7-9). This important domain is untapped in Australia. Hence, as a starting point, we conducted a context analysis to help situate engineering education in a school system. We report on this analysis with respect to findings from one of two literature-based surveys that gathered middle-school student responses in mathematics (n=172) and science (n=166) towards understanding their dispositions for engineering education. ANOVA indicated gender differences for 3 out of 23 items in both mathematics and science. In addition, the majority of students agreed or strongly agreed with 17 of the 23 survey items, however, there were some differences between mathematics and science. We conclude the paper with some recommendations for establishing engineering education in schools, including the development of partnerships among engineering and education faculties, school systems, and industry to develop contemporary engineering resources to support school-level mathematics, science, and technology.