13,234 research outputs found

    Farmers' Demand for Information about Agribusiness

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    This study is focused on the habits of the Brazilian farmers that access the Internet for searching information to their economical activities. The main goal is to understand how come those agents of the agribusiness use the formal and informal (personal contact) means of communication, as well as the functions that each of those means accomplish to this public. In other words, it intends to identify the channels of communication of major importance to farmers (used more often, considered the ones of more credibility and preferred among them). That is possible by means of a questionnaire sent exclusively by e-mail, answered by Brazilian farmers. The motivation of the study is to contribute to make the communication more efficient to those who work on farms. That can produce benefits to the communication companies and to the public. The results show that the Internet is the mean of communication more often used and preferred on the process of searching information about the agribusiness among Brazilian farmers. The personal contact, not considered in the valuation about preference, appears in second position in the ranking for intensity of use. On the other hand, the radio, regional press newspapers and newsletters of class entities were the less consulted and the last ones in the ranking of preference.Agribusiness, Teaching/Communication/Extension/Profession,

    Professores em início de carreira : Formação inicial e saberes da experiencia

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    Trata de uma pesquisa que toma como eixo de reflexao a açao docente de professores de Educaçao Física em início de carreira. A investigaçao analisou as mediaçoes, tensoes e açoes pedagógicas, saber-fazer, desses professores no momento de suas aulas confrontando-os com a formaçao inicial e os saberes constituídos durante as suas trajetórias docentes, que aqui denominaremos de saberes da experiência. A pesquisa tem como objeto de estudo a formaçao inicial e a experiência docente e toma como sujeitos da pesquisa três professores com menos de cinco anos de atuaçao na educaçao básica, em escolas da cidade da Grande Vitória/ES - Brasil. Trata-se de uma pesquisa de natureza qualitativa, caracterizada como um estudo de caso do tipo etnográfico. Os instrumentos metodológicos utilizados foram: observaçoes de aulas, durante três meses, entrevistas semiestruturadas com os sujeitos da pesquisa e grupo focal. A análise contribuiu para reflexao sobre a formaçao inicial vinculada aos aspectos didático-metodológicos da experiência docente. Espera-se com este estudo contribuir com a discussao acerca da formaçao inicial de Professores Licenciados em Educaçao Físic

    Shelf-Ocean material exchange influencing the Atlantic chemical composition off NW Iberian margin since the last glaciation

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    Rivers are the main conduit of sediment to the shelf. The basin geology, the drainage area and the discharge rate are the major factors that determine their sediment load (Milliman and Syvistski, 1992). Besides suspended particles, dissolved components may also give some information on the eroded crust. Sr isotopes in carbonate shells of biological organisms have been used to study, in the geological record, the influence exerted by the chemical weathering of the continental crust on the seawater composition (Macdougall, 1991). In this work, Sr isotope ratios obtained in tests of foraminifera representing the last 40 ka are presented and discussed in the scope of the palaeogeographical evolution of NW Iberia. This work aims to present and discuss the results of Sr isotope analyses (performed, by TIMS, in the Isotope Geology Laboratory of the University of Aveiro) of tests of two species of foraminifera, from nine samples taken along the OMEX core KC 024-19 (181 cm; 42°08’98’’N, 10°29´96’’W, and 2765m), collected in the Galicia Bank area, off Galicia. Taking into account that Sr contained in the carbonate tests is usually considered as preserving the signature of the contemporaneous seawater, one planktonic species (Globigerina bulloides) and one benthic species (Cibicides wuellerstorfi) were selected in order to try to detect Sr isotope variations both through time and between two different levels of the water column. The core age model, which records the last 40 ka, is based on a combination of oxygen isotope stratigraphy, eight AMS 14C datings and the synchronisation of the last four Heinrich Events in the Iberian Margin sedimentary records. As a whole, the obtained 87Sr/86Sr ratios vary between 0.709209 and 0.709108, with a mean 2σ error of 0.000025. These values lie within the range of modern marine Sr isotope ratios (0.70910-0.70922), as previously defined using analyses of both seawater and marine carbonates (see compilation by Faure and Mensing, 2005). Despite their small variation, the 87Sr/86Sr ratios obtained in G. bulloides seem to indicate that Sr dissolved in seawater at the KC 024-19 core site became slightly less radiogenic after the Last Glacial Maximum (LGM). This decrease is concomitant with diminishing amounts of the detrital components in the sediments (Fig. 1). Therefore, both the composition of dissolved Sr, as revealed by results on tests of planktonic foraminifera, and the proportions of suspended terrigenous particulate material arriving at the KC 024-19 site point to a decreasing importance of the contribution of the erosion of the Iberian Variscan crust since the Last Glacial Maximum and in the Holocene. The 87Sr/86Sr ratios measured in tests of benthic foraminifera (C. wuellerstorfi) are more erratic and no correlation can be established with palaeogeographical/palaeoclimatic constraints. The difference between the behaviour of Sr compositions in G. bulloides and C. wuellerstorfi may indicate that whilst the planktonic foraminifera should reproduce very closely the seawater composition, the benthic organisms should, in addition to the major role of seawater, also be affected by some sort of interaction with the sediments. As such, planktonic foraminifera are probably more reliable indicators of seawater composition in studies involving very small periods and corresponding very slight variations of the 87Sr/86Sr ratios. Taking into account that G. bulloides is a common planktonic species (living mostly in the first 50m of the water column), whose tests seem to be in equilibrium with sea water composition, variations in its 87Sr/86Sr ratios can be related with changes in the chemical composition of the water of the Atlantic Ocean off NW Iberian Margin. The highest 87Sr/86Sr values are contemporaneous with a period of low sea level (about -140 m; Dias et al., 2000) during the LGM. According to Dias et al. (2000) at 18 ka BP the shoreline was close to the shelf break. The summital parts of the Gerês and Estrela mountains were covered by local glaciers and close to the coast freezing occurred frequently. The river catchments, which extended far to the shelf, received more rainfall due to a longer, compared to present day conditions, wet season, which promoted both physical and chemical weathering. Higher pluviosity combined with the effect of spring ice melting maintained high river discharge and consequently caused very important sediment supply to the coastal zone. The extremely narrow shelf was a very energetic environment due to sea bottom inclination and very limited long wave refraction. Therefore, at that time, a long wet season and very competent rivers should have caused important erosion of the Variscan basement in NW Iberia. Additionally, then, the shoreline was much closer to the KC 024-19 site. The combination of all these factors favoured an important deposition of terrigenous sediments and the local slight enrichment in radiogenic Sr of the seawater. With sea level rise, after the deglaciation and during the Holocene, the river estuaries became progressively far away from the shelf break. Their competence of transport also became progressively reduced and the offshore transport of detrital sediments became progressively lower. Conversely the biogenic carbonate proportion in the sediments increased, due to lower dilution by the terrigenous particles. Simultaneously, the values of 87Sr/86Sr in the seawater at the KC 024-19 site became lower, as a consequence of a complete homogenization with the ocean global composition, which was now more effective with the increasing distance towards shoreline

    proposta e análise de um conteúdo programático

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    Tese de mestrado, Educação artística, Universidade de Lisboa, Faculdade de Belas Artes, 2011This study aims to investigate how the use of a specific syllabus built around the convergence with works of art fosters the development of four and five year old children, with regard to concepts, behaviour and performance of activities of artistic expression. The aim is made explicit through the body of scientific literature that evokes the free expression of the child, and identifies the school and its professionals as being responsible for the stimulation of child creativity, the convergence with works of art is one of the possible pathways. The study evaluated the impact of specific syllabus content that focused on the ability of children to identify and distinguish different forms of art, to contemplate diverse activities and materials of the artistic expression area, and to combine various materials in the same creation. Twenty children aged four and five years and attending two classes in a nursery school in Lisbon took part in the study. These children were subjected to a specific experimental condition developed in ten intervention sessions. This study adopts the function of a case study. The results showed significant changes in the behaviour and performance of the children in relation to the use of materials, the discovery of new technical and material possibilities and in identifying different forms of art. It can therefore be concluded that it is possible to stimulate the development of these abilities in four and five year old children, and that the use of a syllabus built around the convergence with works of art is enriching in the nursery school environment
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