913 resultados para Long non-coding RNA
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In part because of high and persistent youth unemployment, adolescent students’ transition from school to work is an important policy and research topic. Many countries have implemented public programs offering summer jobs or work while in high-school as measures to smooth the transition. While the immediate effect of the programs on school attendance, school grades, and disposable income is well documented, their effect on the transition to the labor market remains an open question. Observational studies have shown strong positive effects of summer jobs, but also that the estimated effect is highly vulnerable to selection bias. In this paper, some 3700 high-school students applying for summer jobs in the period 1995-2003,via a program, are followed to 30 years of age. A quarter of the applicants were randomly offered a summer job each year. Among the remaining students, 50% had a (non-program related) summer job while in high-school. We find the income, post high-school, for the offered and non-offered groups to be similar and conclude that the effect of summer jobs on the transition to the labor market is inconsequential.
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O Brasil é um dos principais atores do novo ambiente econômico mundial, mas para permanecer atrativo, deve fazer progressos significativos no campo das Tecnologias de Informação e da Comunicação (TIC). Assim, um serviço de internet banda larga é primordial para o desenvolvimento de regiões distantes, geralmente de baixa renda e que não têm acesso a instalações de telecomunicações, nem aos serviços de internet banda larga. De fato, a penetração da banda larga no Brasil apresenta situação inferior à média mundial e boa parte da população ainda está excluída do mundo digital por causa das desigualdades sociais e as dimensões continentais do país. Para preencher esta lacuna, o governo federal lançou, em 2010, o Programa Nacional de Banda Larga (PNBL). No entanto, a penetração de banda larga permanece em níveis baixos, mesmo em grandes centros urbanos e com uma distribuição regional desigual, especialmente quando comparados internacionalmente. As concessionárias não estão desempenhando o seu papel de universalização dos serviços de banda larga e as pequenas e médias operadoras podem desempenhar um papel fundamental na promoção desse objetivo. Esse trabalho tem o propósito de investigar se é possível conciliar o modelo vigente de telecomunicações regido pela Lei Geral das Telecomunicações (LGT) com a universalização dos serviços de banda larga, desde que apoiado num mercado competitivo e menos concentrado, com pequenas e médias operadoras. Como verificação, foi feito um trabalho empírico com base em entrevistas semiestruturadas com profissionais de telecomunicações do setor público e privado, assim como uma análise de padrão de codificação dessas entrevistas. Os resultados mostram, porém, que o ambiente regulatório atual pode gerar incentivos à operação de qualidade nas áreas remotas e de baixa renda, mas não de forma generalizada. A universalização requer uma mudança estrutural do modelo e é a política pública federal que deve dar as diretrizes, com objetivos claros. Tampouco há modelo ideal de regulação, mas um entorno regulatório adequado pode ser motor de desenvolvimento do setor. O estabelecimento de compromissos entre os atores também é fundamental, assim como a decisão política na origem, dando suporte para o planejamento e projetos de longo prazo. E é a partir dessa decisão que se desenvolvem as medidas regulatórias de competição e fiscalização que vão garantir a execução do que foi previsto e desenhado.
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We evaluate the forecasting performance of a number of systems models of US shortand long-term interest rates. Non-linearities, induding asymmetries in the adjustment to equilibrium, are shown to result in more accurate short horizon forecasts. We find that both long and short rates respond to disequilibria in the spread in certain circumstances, which would not be evident from linear representations or from single-equation analyses of the short-term interest rate.
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This thesis presents a low cost non-intrusive home energy monitor built on top of Non-Intrusive Load Monitoring (NILM) concepts and techniques. NILM solutions are already considered low cost alternatives to the big majority of existing commercial energy monitors but the goal here is to make its cost even lower by using a mini netbook as a whole in one solution. The mini netbook is installed in the homes main circuit breaker and computes power consumption by reading current and voltage from the built-in sound card. At the same time, feedback to the users is provided using the 11’’ LCD screen as well as other built-in I/O modules. Our meter is also capable of detecting changes in power and tries to find out which appliance lead to that change and it is being used as part of an eco-feedback platform that was build to study the long terms of energy eco-feedback in individuals. In this thesis the steps that were taken to come up with such a system are presented, from the basics of AC power measurements to the implementation of an event detector and classifier that was used to disaggregate the power load. In the last chapter results from some validation tests that have been performed are presented in order to validate the experiment. It is believed that such a system will not only be important as an energy monitor, but also as an open system than can be easily changed to accommodate and test new or existing nonintrusive load monitoring techniques.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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To determine the incidence of rotavirus infection among dairy herds in the State of Sdo Paulo, Brazil, 576 faecal samples obtained from calves aged 1-45 days with and without diarrhoea, reared on 63 dairy cattle farms, were analyzed. Polyacrylamide gel electrophoresis (PAGE) identified 28 samples positive for group A rotavirus, while four samples, two diarrhoeic and two non-diarrhoeic, showed a bisegmented genome with a typical picobirnavirus pattern. Electron microscopy revealed spherical virus particles with a diameter of 37 nm and without a defined surface structure. The present study is the first report of a bisegmented virus identified in cattle in Brazil. (C) 2003 Elsevier B.V. Ltd. All rights reserved.
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Thaumastocoris peregrinus is a recently introduced invertebrate pest of non-native Eucalyptus plantations in the Southern Hemisphere. It was first reported from South Africa in 2003 and in Argentina in 2005. Since then, populations have grown explosively and it has attained an almost ubiquitous distribution over several regions in South Africa on 26 Eucalyptus species. Here we address three key questions regarding this invasion, namely whether only one species has been introduced, whether there were single or multiple introductions into South Africa and South America and what the source of the introduction might have been. To answer these questions, bar-coding using mitochondrial DNA (COI) sequence diversity was used to characterise the populations of this insect from Australia, Argentina, Brazil, South Africa and Uruguay. Analyses revealed three cryptic species in Australia, of which only T. peregrinus is represented in South Africa and South America. Thaumastocoris peregrinus populations contained eight haplotypes, with a pairwise nucleotide distance of 0.2-0.9% from seventeen locations in Australia. Three of these haplotypes are shared with populations in South America and South Africa, but the latter regions do not share haplotypes. These data, together with the current distribution of the haplotypes and the known direction of original spread in these regions, suggest that at least three distinct introductions of the insect occurred in South Africa and South America before 2005. The two most common haplotypes in Sydney, one of which was also found in Brisbane, are shared with the non-native regions. Sydney populations of T. peregrinus, which have regularly reached outbreak levels in recent years, might thus have served as source of these three distinct introductions into other regions of the Southern Hemisphere.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Bats are main reservoirs for Lyssavirus worldwide, which is an important public health issue because it constitutes one of the big challenges in rabies control. Yet, little is known about how the virus is maintained among bats, and the epidemiological relationships remain poorly understood. The aim of the present study was to investigate the distribution of the rabies virus (RABV) in bat tissues and organs and to genetically characterize virus isolates from naturally infected non-hematophagous bats. The heminested reverse transcriptase polymerase chain reaction (hnRT-PCR) and sequencing using primers to the nucleoprotein coding gene were performed. The results showed a dissemination of the RABV in different tissues and organs, particularly in the salivary glands, tongue, lungs, kidneys, bladder, intestine and feces, suggesting other possible forms of RABV elimination and the possibility of transmission among these animals. The phylogenetic analysis confirmed that different variants of RABV are maintained by non-hematophagous bats in nature and have similar tissue distribution irrespective of bat species and phylogenetic characterization. (C) 2012 Elsevier B.V. All rights reserved.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Within about 30 years the Brazilian buffalo (Bubalus bubalis) herd will reach approximately 50 million head as a result of the great adaptive capacity of these animals to tropical climates, together with the good productive and reproductive potential which make these animals an important animal protein source for poor and developing countries. The myostatin gene (GDF8) is important in the physiology of stock animals because its product produces a direct effect on muscle development and consequently also on meat production. The myostatin sequence is known in several mammalian species and shows a high degree of amino acid sequence conservation, although the presence of non-silent and silent changes in the coding sequences and several alterations in the introns and untranslated regions have been identified. The objective of our work was to characterize the myostatin coding regions of B. bubalis (Murrah breed) and to compare them with the Bos taurus regions looking for variations in nucleotide and protein sequences. In this way, we were able to identify 12 variations at DNA level and five alterations on the presumed myostatin protein sequence as compared to non double-muscled bovine sequences.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The evolutionary origin of beetle bioluminescence is enigmatic. Previously, weak luciferase activity was found in the non-bioluminescent larvae of Tenebrio molitor (Coleoptera: Tenebrionidae), but the detailed tissular origin and identity of the luciferase-like enzyme remained unknown. Using a closely related giant mealworm, Zophobas morio, here we show that the luciferase-like enzyme is located in the Malpighi tubules. cDNA cloning of this luciferase like enzyme, showed that it is a short AMP-ligase with weak luciferase activity which diverged long ago from beetle luciferases. The results indicate that the potential for bioluminescence in AMP-ligases is very ancient and provide a first reasonable protoluciferase model to investigate the origin and evolution of beetle luciferases.
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1. The aim of the present study was to examine the effects of long-term nitric oxide (NO) blockade on contractions of the rat ileum induced by muscarinic agonists.2. Male Wistar rats received the NO synthesis inhibitor N (G) -nitro-l-arginine methyl ester (l-NAME; 20 mg/rat per day) in drinking water for 7, 15, 30 and 60 days. Concentration-responses curves to methacholine and carbachol were obtained and pEC(50) values were calculated. Saturation binding assays were performed in membranes prepared from rat ileum after 60 days of l-NAME treatment and the dissociation constant (K-D ) and maximal number of binding sites (B-max ) were determined by Scatchard analysis.3. The NO synthase activity of the ileum was markedly reduced in all l-NAME-treated groups. At 60 days after l-NAME treatment, a significant increase in the potency of methacholine (fourfold) and carbachol (threefold) was observed. In binding studies, we found a significant increase in B-max for [(3) H]-quinuclidinyl benzilate of approximately 57% in the l-NAME treated group without any significant change in K-D values. The contractile response to methacholine was not modified by the soluble guanylate cyclase inhibitor 1H-[1,2,4]oxadiazolo-[4,3-a]quinoxalin-1-one (3 mumol/L). No morphological alterations in the rat ileum were observed in l-NAME-treated rats.4. Our findings suggest that treatment with l-NAME for 60 days induces a marked increase in the potency of methacholine and carbachol, as well as an increase in receptor number in the rat ileum.