994 resultados para knowledge flows


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Neste trabalho procuramos atualizar e acrescentar observações novas ao conhecimento dos Strepsiptera do Brasil. Descrevemos 4 espécies novas da família Myrmecolacidae, representados apenas por machos e uma espécie nova da família Halictophagidae, representada por macho, fêmea e hospedador. Registramos a ocorrência, no Brasil, de uma espécie da família Stylopidae, conhecida anteriormente da Argentina e fornecemos dados adicionais sôbre uma espécie da família Mengeidae, Triozocera paulistana Kogan, 1958. Baseados em HOFENEDER & FULMEK (1942-43) damos a lista dos hospedadores encontrados estilopizados no Brasil.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The objective of this paper is to measure the impact of different kinds of knowledge and external economies on urban growth in an intraregional context. The main hypothesis is that knowledge leads to growth, and that this knowledge is related to the existence of agglomeration and network externalities in cities. We develop a three-tage methodology: first, we measure the amount and growth of knowledge in cities using the OCDE (2003) classification and employment data; second, we identify the spatial structure of the area of analysis (networks of cities); third, we combine the Glaeser - Henderson - De Lucio models with spatial econometric specifications in order to contrast the existence of spatially static (agglomeration) and spatially dynamic (network) external economies in an urban growth model. Results suggest that higher growth rates are associated to higher levels of technology and knowledge. The growth of the different kinds of knowledge is related to local and spatial factors (agglomeration and network externalities) and each knowledge intensity shows a particular response to these factors. These results have implications for policy design, since we can forecast and intervene on local knowledge development paths.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

No presente trabalho são redescritas as seguintes espécies do gênero Archytas Jaennicke, 1867: Archytas lateralis Macquart, 1842, Archytas metallicus Desvoidy, 1830; Archytas aterrimus Desvoidy, 1830 e Archytas willistoni Curran, 1925. São ainda descritas duas espécies novas, provenientes do Estado do Pará, Brasil: Archytas pearsoni e A. araujoi. O material estudado pertence à coleção do Instituto Oswaldo Cruz, Rio de Janeiro.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In this paper the authors refere Philometra lateolabracis Yamaguti, 1935 for the first time from the Atlantic Ocean also as a new host record. They report the rpesence of one male of diminished dimensions, found in close relationship with the females of Ph. lateolabracis; as the male of this species is unknown, they admit the possibility of this small nematode be the male of this species.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Scandals of selective reporting of clinical trial results by pharmaceutical firms have underlined the need for more transparency in clinical trials. We provide a theoretical framework which reproduces incentives for selective reporting and yields three key implications concerning regulation. First, a compulsory clinical trial registry complemented through a voluntary clinical trial results database can implement full transparency (the existence of all trials as well as their results is known). Second, full transparency comes at a price. It has a deterrence effect on the incentives to conduct clinical trials, as it reduces the firms'gains from trials. Third, in principle, a voluntary clinical trial results database without a compulsory registry is a superior regulatory tool; but we provide some qualified support for additional compulsory registries when medical decision-makers cannot anticipate correctly the drug companies' decisions whether to conduct trials. Keywords: pharmaceutical firms, strategic information transmission, clinical trials, registries, results databases, scientific knowledge JEL classification: D72, I18, L15

Relevância:

20.00% 20.00%

Publicador:

Resumo:

We analyse natural resource use dynamics in the Mexican economy during the last three decades. Despite low and uneven economic growth, the extraction and use of materials in the Mexican economy has continuously increased during the last 30 years. In this period, population growth rather than economic growth was the main driving force for biophysical growth. In addition, fundamental changes have taken place in the primary sectors, in manufacturing, and in household consumption and these are reflected in an increasing emphasis on the use of fossil fuels and construction materials. Mexico’s economy has been strongly influenced by international trade since the country commenced competing in international markets. In the 1970s, Mexico mainly exported primary resources. This pattern has changed and manufactured goods now have a much greater importance due to a boom in assembling industries. In contrast with other Latin American countries, Mexico has achieved a diversification of production, moving towards technology-intensive products and a better mix in its export portfolio. However, crude oil exports still represent the single most important export good. Mexico’s material consumption is still well below the OECD average but is growing fast and the current resource use patterns may well present serious social and environmental problems to the medium and long term sustainability of Mexico’s economy and community. Information on natural resource use and resource productivity could provide valuable guidance for economic policy planning in Mexico.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

First and second instar larvae of some Sarcophagidae (Diptera) of the tribe Raviniini are described on observations with a scanning electron microscope.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

L1, L2 and L3 of Oxysarcodexia paulistanensis (Mattos), L3 of O. confusa Lopes, L2 of Ravinia belforti (Prado & Fonseca) and L2 of Oxyvinia excisa (Lopes) were described and figured using scanning electron microscope.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Gestures are the first forms of conventional communication that young children develop in order to intentionally convey a specific message. However, at first, infants rarely communicate successfully with their gestures, prompting caregivers to interpret them. Although the role of caregivers in early communication development has been examined, little is known about how caregivers attribute a specific communicative function to infants' gestures. In this study, we argue that caregivers rely on the knowledge about the referent that is shared with infants in order to interpret what communicative function infants wish to convey with their gestures. We videotaped interactions from six caregiver-infant dyads playing with toys when infants were 8, 10, 12, 14, and 16 months old. We coded infants' gesture production and we determined whether caregivers interpreted those gestures as conveying a clear communicative function or not; we also coded whether infants used objects according to their conventions of use as a measure of shared knowledge about the referent. Results revealed an association between infants' increasing knowledge of object use and maternal interpretations of infants' gestures as conveying a clear communicative function. Our findings emphasize the importance of shared knowledge in shaping infants' emergent communicative skills.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Forest fires are a serious threat to humans and nature from an ecological, social and economic point of view. Predicting their behaviour by simulation still delivers unreliable results and remains a challenging task. Latest approaches try to calibrate input variables, often tainted with imprecision, using optimisation techniques like Genetic Algorithms. To converge faster towards fitter solutions, the GA is guided with knowledge obtained from historical or synthetical fires. We developed a robust and efficient knowledge storage and retrieval method. Nearest neighbour search is applied to find the fire configuration from knowledge base most similar to the current configuration. Therefore, a distance measure was elaborated and implemented in several ways. Experiments show the performance of the different implementations regarding occupied storage and retrieval time with overly satisfactory results.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In this paper we attempt an empirical application of the multi-region input-output (MRIO) method in order to enumerate the pollution content of interregional trade flows between five Mid-West regions/states in the US –Illinois, Indiana, Iowa, Michigan and Wisconsin – and the rest of the US. This allows us to analyse some very important issues in terms of the nature and significance of interregional environmental spillovers within the US Mid-West and the existence of pollution ‘trade balances’ between states. Our results raise questions in terms of the extent to which authorities at State level can control local emissions where they are limited in the way some emissions can be controlled, particularly with respect to changes in demand elsewhere in the Mid-West and US. This implies a need for policy co-ordination between national and state level authorities in the US to meet emissions reductions targets. The existence of an environmental trade balances between states also raises issues in terms of net losses/gains in terms of pollutants as a result of interregional trade within the US and whether, if certain activities can be carried out using less polluting technology in one region relative to others, it is better for the US as a whole if this type of relationship exists.