998 resultados para Redes de informação de Ciencia e Tecnologia


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Persistent beta-adrenergic receptor stimulation with isoproterenol is associated with cardiac hypertrophy as well as cardiac synthesis of angiotensin II. Serum- and glucocorticoid-regulated kinase type 1 (SGK-1) is a key mediator in structural, functional and molecular cardiac effects of aldosterone in rats. This study was designed to investigate the cardiac effects of the mineralocorticoid receptor antagonist spironolactone on the response to isoproterenol treatment in rats, as well as the involvement of the main mediator of cellular aldosterone action, SGK-1, in the heart. Male Wistar rats received isoproterenol (3 mg kg-1 day-1) or vehicle for 15 days. Half of the animals in each group were simultaneously treated with spironolactone (200 mg kg-1 day-1). Systolic and diastolic blood pressures were not significantly different among groups. Treatment with spironolactone normalized the increased left ventricular end-diastolic pressure observed in isoproterenol-treated rats. Isoproterenol treatment induced cardiac hypertrophy and increased collagen content, both of which were normalized by spironolactone treatment. The mRNA levels of transforming growth factor beta, connective tissue growth factor, matrix metalloprotease 2, matrix metalloprotease inhibitor 2, tumour necrosis factor a, interleukin 1 beta, p22phox and xanthine dehydrogenase were increased (P < 0.05) in isoproterenol-treated rats, and this effect was prevented by spironolactone (P < 0.05). Spironolactone also reduced the elevated SGK-1 expression in isoproterenol-treated rats. The observed reduction of the principal mediator of aldosterone cellular actions, SGK-1, by spironolactone in hearts from isoproterenol-treated rats suggests a role of mineralocorticoids in the cardiac hypertrophy, fibrosis, inflammation, oxidation and diastolic dysfunction induced by isoproterenol treatment in rats.

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Background: Dengue is the most important mosquito-borne viral disease worldwide. Dengue virus comprises four antigenically related viruses named dengue virus type 1 to 4 (DENV1-4). DENV-3 was re-introduced into the Americas in 1994 causing outbreaks in Nicaragua and Panama. DENV-3 was introduced in Brazil in 2000 and then spread to most of the Brazilian States, reaching the neighboring country, Paraguay in 2002. In this study, we have analyzed the phylogenetic relationship of DENV-3 isolated in Brazil and Paraguay with viruses isolated worldwide. We have also analyzed the evolutionary divergence dynamics of DENV-3 viruses. Results: The entire open reading frame (ORF) of thirteen DENV-3 isolated in Brazil (n = 9) and Paraguay (n = 4) were sequenced for phylogenetic analysis. DENV-3 grouped into three main genotypes (I, II and III). Several internal clades were found within each genotype that we called lineage and sub-lineage. Viruses included in this study belong to genotype III and grouped together with viruses isolated in the Americas within the lineage III. The Brazilian viruses were further segregated into two different sub-lineage, A and B, and the Paraguayan into the sub-lineage B. All three genotypes showed internal grouping. The nucleotide divergence was in average 6.7% for genotypes, 2.7% for lineages and 1.5% for sub-lineages. Phylogenetic trees constructed with any of the protein gene sequences showed the same segregation of the DENV-3 in three genotypes. Conclusion: Our results showed that two groups of DENV-3 genotypes III circulated in Brazil during 2002-2009, suggesting different events of introduction of the virus through different regions of the country. In Paraguay, only one group DENV-3 genotype III is circulating that is very closely related to the Brazilian viruses of sub-lineage B. Different degree of grouping can be observed for DENV-3 and each group showed a characteristic evolutionary divergence. Finally, we have observed that any protein gene sequence can be used to identify the virus genotype.

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Background. Respiratory syncytial virus (RSV) has been implicated in the etiology of adult community-acquired pneumonia (CAP). We investigated RSV infection in Chilean adults with CAP using direct viral detection, real-time reverse-transcription polymerase chain reaction (rtRT-PCR), and serology (microneutralization assay). Methods. RSV, other respiratory viruses, and bacteria were studied by conventional and molecular techniques in adults aged >= 18 years presenting with CAP to the healthcare facilities in Santiago, Chile from February 2005 through December 2007. Results. All 356 adults with CAP enrolled had an acute blood sample collected at enrollment, and 184 had a convalescent blood sample. RSV was detected in 48 cases (13.4%). Immunofluorescence assay and viral isolation each detected only 1 infection (0.2%), whereas rtRT-PCR was positive in 32 (8.9%) cases and serology was positive in 20 (10.8%) cases. CAP clinical characteristics were similar in RSV-infected and non-RSV-infected cases. RSV-specific geometric mean serum-neutralizing antibody titer (GMST) was significantly lower at admission in the 48 RSV-infected cases compared with 308 non-RSV-infected adults (GMST in log(2): RSV/A 8.1 vs 8.9, and RSV/B 9.3 vs 10.4; P < .02). Conclusions. RSV infection is frequent in Chilean adults with CAP. Microneutralization assay was as sensitive as rtRT-PCR in detecting RSV infection and is a good adjunct assay for diagnostic research. High RSV-specific serum-neutralizing antibody levels were associated with protection against common and severe infection. The development of a vaccine could prevent RSV-related CAP in adults.

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The persistent luminescence of CdSiO3:Tb3+ was investigated with photoluminescence, thermoluminescence (TL), synchrotron radiation X-ray absorption (XANES and EXAFS) and UV-VUV spectroscopies. Only the typical intraconfigurational 4f(8)-4f(8) transitions of the Tb3+ ion were observed with no traces of band emission in either the conventional UV excited or persistent luminescence spectra. The trap structure from TL with three traps from 0.65 to 0.85 eV is ideal for room-temperature persistent luminescence similar to, e.g., Sr2MgSi2O7:Eu2+,R3+. Despite the rather low band gap energy, 5.28 eV, the persistent luminescence from Tb3+ is produced only under UV irradiation due to the inauspicious position of the F-7(6) ground level deep in the band gap of CdSiO3. This confirms the role of electrons as the charge carriers in the mechanism of Tb3+ persistent luminescence. The XANES spectra indicated the presence of only the trivalent Tb3+ species, thus excluding the direct Tb3+ -> Tb-IV oxidation during the charging process of persistent luminescence. Eventually, a unique persistent luminescence mechanism for Tb3+ in CdSiO3 was constructed based on the comprehensive experimental data.

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Native Inga laurina (Fabaceae) trypsin inhibitor (ILTI) was tested for anti-insect activity against Diatraea saccharalis and Heliothis virescens larvae. The addition of 0.1% ILTI to the diet of D. saccharalis did not alter larval survival but decreased larval weight by 51%. The H. virescens larvae that were fed a diet containing 0.5% ILTI showed an 84% decrease in weight. ILTI was not digested by the midgut proteinases of either species of larvae. The trypsin levels were reduced by 55.3% in the feces of D. saccharalis and increased by 24.1% in the feces of H. virescens. The trypsin activity in both species fed with ILTI was sensitive to the inhibitor, suggesting that no novel proteinase resistant to ILTI was induced. Additionally, ILTI exhibited inhibitory activity against the proteinases present in the larval midgut of different species of Lepidoptera. The organization of the ilti gene was elucidated by analyzing its corresponding genomic sequence. The recombinant ILTI protein (reILTI) was expressed and purified, and its efficacy was evaluated. Both native ILTI and reILTI exhibited a similar strong inhibitory effect on bovine trypsin activity. These results suggest that ILTI presents insecticidal properties against both insects and may thus be a useful tool in the genetic engineering of plants. (c) 2012 Elsevier Inc. All rights reserved.

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LOCKSS e preservação digital no BRASIL. Podemos definir Preservação Digital como o conjunto de atividades ou processos responsáveis por garantir o acesso contínuo a longo-prazo à informação científica, tecnológica e cultural existente em formatos digitais. O projeto LOCKSS (Lot Of Copies Keep Stuff Safe) é um software de código aberto desenvolvido pela Universidade de Stanford, com o intuito de preservar dados digitais. Possui uma abordagem peer-to-peer e garante a integridade e disponibilidade do dos acervos digitais preservados. No Brasil, a Rede Brasileira de Serviços de Preservação Digital, ou Rede Cariniana, é uma iniciativa do Instituto Brasileiro de Informação em Ciência e Tecnologia para a salvaguarda do patrimônio científico, tecnológico e cultural, de forma distribuída, por instituições de pesquisa em parceria com o IBICT. Sua implantação foi fundamentada na utilização do LOCKSS em uma infraestrutura descentralizada, utilizando recursos de computação distribuída .

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Entre os vários fatores que contribuem para a produção de uma cultura de milho, a distribuição vertical dos semeadores avaliada através da localização da semente em profundidade é um fator-chave, especialmente na técnica de sementeira direta. Simultaneamente, dada a complexidade dos ecossistemas naturais e agrícolas em sistemas de agricultura de conservação, a gestão diferenciada e localizada das parcelas assume um importante papel na análise e gestão da variabilidade das propriedades do solo e estabelecimento das culturas, nomeadamente utilizando informação geo referenciada e tecnologia expedita. Assim, o principal objetivo desta Tese foi a avaliação em culturas de milho da variabilidade espacial da localização de semente em profundidade e estabelecimento da cultura em sementeira direta usando sistemas convencionais de controlo de profundidade, tendo-se comparado com diferentes sistemas de mobilização e recorrendo a tecnologias de agricultura de precisão. Os ensaios decorreram na região Mediterrânea do Alentejo, em propriedades agrícolas no decorrer das campanhas de 2010, 2011, 2012 e 2015 em 6 diferentes campos experimentais. O trabalho experimental consistiu em ensaios com avaliações in loco do solo e cultura, consumo de combustível das operações e deteção remota. Os resultados obtidos indicam que não só o sistema de mobilização afetou a localização da semente em profundidade, como em sementeira direta a profundidade de sementeira foi afetada pelo teor de humidade do solo, resistência do solo à profundidade e velocidade da operação de sementeira. Adicionalmente observaram-se condições heterogéneas de emergência e estabelecimento da cultura afetadas por condições físicas de compactação do solo. Comparando os diferentes sistemas de mobilização, obteve-se uma significativa redução de combustível para a técnica de sementeira direta, apesar de se terem observado diferenças estatísticas significativas considerando diferentes calibrações de profundidade de sementeira Do trabalho realizado nesta Tese ressalva-se a importância que as tecnologias de agricultura de precisão podem ter no acompanhamento e avaliação de culturas em sementeira direta, bem como a necessidade de melhores procedimentos no controlo de profundidade dos semeadores pelo respetivos operadores ou ao invés, a adoção de semeadores com mecanismos ativos de controlo de profundidade. ABSTRACT Among the various factors that contribute towards producing a successful maize crop, seeders vertical distribution evaluated through seed depth placement is a key determinant, especially under a no-tillage technique. At the same time in conservation agriculture systems due to the complexity of natural and agricultural ecosystems site specific management became an important approach to understand and manage the variability of soil properties and crop establishment, especially when using geo spatial information and affording readily technology Thus, the main objective of this Thesis was to evaluate the spatial variability of seed depth placement and crop establishment in maize crops under no-tillage conditions compared to different tillage systems, using conventional seed depth control no till seeders and precision farming technologies. Trials were carried out in the Mediterranean region of Alentejo, in private farms along the sowing operations season over the years 2010, 2011, 2012 and 2015 in 6 different experimental fields. Experimental work covered field tests with in loco soil and crop evaluations, fuel operation evaluations and aerial sensing. The results obtained indicate that not only tillage system affected seed depth placement but under no till conditions seed depth was affected by soil moisture content, soil resistance to penetration and seeders forward speed. In addition uneven crop seedling and establishment depended on seed depth placement and could be affected by physical problems of compaction layers. Significant reduction in fuel consumption was observed for no till operations although significant differences observed according to different setting calibrations of seed depth control. According to the results, precision agriculture is an important tool to evaluate crops under no till conditions and seed depth mechanisms should be more accurate by the operators or is determinant the adoption of new active depth control technology to improve seeders performance.

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Date of acceptance: 06/12/2014 Acknowledgments The study was funded by the Portuguese Ministry of Science (Fundac¸a˜o para a Cieˆncia e Tecnologia– FCT) through a PhD Grant of SG (SFRH/BD/47931/2008). We would like to thank the captain of the purse-seiner (Jose´ Manuel Saveedra) and his crew for facilitating the capture and transport of live fish. Moreover, we want to thank Ana Marc¸alo for suggestions on the experimental design, Manuel Garci for technical advice on underwater video recordings and James Turner from the company Future Oceans for providing technical details on the 70 kHz dolphin pingers. We would also like to acknowledge the scientific advice of Dr. Jose´ Iglesias and the technical and logistic support for the preparation of the laboratory and the materials for tank experiments by Enrique Martı´nez Gonza´lez, Ricardo Pazo´and other staff at the aquaculture facilities of the Spanish Institute for Oceanography (IEO) and the Marine Sciences Station of Toralla (ECIMAT) in Vigo. Furthermore, we are grateful to Francisco de la Granda Grandoso for his practical assistance during the fish tank experiments and to Juan Santos Blanco for helping with statistical analysis. Finally, we would like to thank Pilar Riobo´ Agula, Amelia Fernandez Villamarin, Jose´ Franco Soler, Jose´ Luis Mun˜oz, Angela Benedetti, Marcos Antonio Lopez Patin˜o and Marta Conde Sieira for scientific advice and practical support with cortisol analysis and Rosana Rodrı´guez for preparing histological samples for us.

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The changes in mechanical properties of portland cement mortars due to the addition of carbon fibres (CF) to the mix have been studied. Compression and flexural strengths have been determined in relation to the amount of fibres added to the mix, water/binder ratio, curing time and porosity. Additionally, the corrosion level of reinforcing steel bars embedded in portland cement mortars containing CF and silica fume (SF) have also been investigated and reinforcing steel corrosion rates have been determined. As a consequence of the large concentration of oxygen groups in CF surface, a good interaction between the CF and the water of the mortar paste is to be expected. A CF content of 0.5% of cement weight implies an optimum increase in flexural strength and an increase in embedded steel corrosion.

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Background: Chitosan oligosaccharide (COS), a deacetylated derivative of chitin, is an abundant, and renewable natural polymer. COS has higher antimicrobial properties than chitosan and is presumed to act by disrupting/permeabilizing the cell membranes of bacteria, yeast and fungi. COS is relatively non-toxic to mammals. By identifying the molecular and genetic targets of COS, we hope to gain a better understanding of the antifungal mode of action of COS. Results: Three different chemogenomic fitness assays, haploinsufficiency (HIP), homozygous deletion (HOP), and multicopy suppression (MSP) profiling were combined with a transcriptomic analysis to gain insight in to the mode of action and mechanisms of resistance to chitosan oligosaccharides. The fitness assays identified 39 yeast deletion strains sensitive to COS and 21 suppressors of COS sensitivity. The genes identified are involved in processes such as RNA biology (transcription, translation and regulatory mechanisms), membrane functions (e.g. signalling, transport and targeting), membrane structural components, cell division, and proteasome processes. The transcriptomes of control wild type and 5 suppressor strains overexpressing ARL1, BCK2, ERG24, MSG5, or RBA50, were analyzed in the presence and absence of COS. Some of the up-regulated transcripts in the suppressor overexpressing strains exposed to COS included genes involved in transcription, cell cycle, stress response and the Ras signal transduction pathway. Down-regulated transcripts included those encoding protein folding components and respiratory chain proteins. The COS-induced transcriptional response is distinct from previously described environmental stress responses (i.e. thermal, salt, osmotic and oxidative stress) and pre-treatment with these well characterized environmental stressors provided little or any resistance to COS. Conclusions: Overexpression of the ARL1 gene, a member of the Ras superfamily that regulates membrane trafficking, provides protection against COS-induced cell membrane permeability and damage. We found that the ARL1 COS-resistant over-expression strain was as sensitive to Amphotericin B, Fluconazole and Terbinafine as the wild type cells and that when COS and Fluconazole are used in combination they act in a synergistic fashion. The gene targets of COS identified in this study indicate that COS’s mechanism of action is different from other commonly studied fungicides that target membranes, suggesting that COS may be an effective fungicide for drug-resistant fungal pathogens.

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Resolución 659(XXXIV) Calendario De Conferencias De La Cepal Para El Período 2012-2014 .-- Resolución 660(XXXIV) Comité De Desarrollo Y Cooperación Del Caribe .-- Resolución 661(XXXIV) Lugar Del Próximo Período De Sesiones .-- Resolución 662(XXXIV) Admisión De Las Bermudas Como Miembro Asociado De La Comisión Económica Para América Latina Y El Caribe .-- Resolución 663(XXXIV) Admisión De Curaçao Como Miembro Asociado De La Comisión Económica Para América Latina Y El Caribe .-- Resolución 664(XXXIV) Admisión De Guadalupe Como Miembro Asociado De La Comisión Económica Para América Latina Y El Caribe .-- Resolución 665(XXXIV) Admisión De Martinica Como Miembro Asociado De La Comisión Económica Para América Latina Y El Caribe .-- Resolución 666(XXXIV) Resolución De San Salvador .-- Resolución 667(XXXIV) Conferencia Regional Sobre La Mujer De América Latina Y El Caribe .-- Resolución 668(XXXIV) Conferencia Estadística De Las Américas De La Comisión Económica Para América Latina Y El Caribe .-- Resolución 669(XXXIV) Actividades De La Comisión Económica Para América Latina Y El Caribe En Relación Con El Seguimiento De Los Objetivos De Desarrollo Del Milenio Y La Aplicación De Los Resultados De Las Grandes Conferencias Y Cumbres De Las Naciones Unidas En Las Esferas Económica Y SocialY Esferas Conexas .-- Resolución 670(XXXIV) Comité Especial De La Comisión Económica Para América Latina Y El Caribe Sobre Población Y Desarrollo .-- Resolución 671(XXXIV) Respaldo A La Labor Del Instituto Latinoamericano Y Del Caribe De Planificación Económica Y Social (ILPES) .-- Resolución 672(XXXIV) Establecimiento De La Conferencia De Ciencia, Innovación Y Tecnologías De La Información Y Las Comunicaciones .-- Resolución 673(XXXIV) Programa De Trabajo De La Comisión Económica Para América Latina Y El Caribe Y Prioridades Para El Bienio 2014-2015 .-- Resolución 674(XXXIV) La Dimensión Regional Del Desarrollo .-- Resolución 675(XXXIV) Cooperación Sur-Sur.

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2000 Mathematics Subject Classification: 60J80.

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2000 Mathematics Subject Classification: 60J80, 60J10.

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The Brazilian CAPES Journal Portal aims to provide Information in Science and Technology (IST) for academic users. Thus, it is considered a relevant instrument for post-graduation dynamics and the country´s Science and Technology (S&T) development. Despite its importance, there are still few studies that focus on the policy analysis and efficiency of these resources. This research aims to fill in this gap once it proposes an analysis of the use of the CAPES Journal Portal done on behalf of the master´s and doctoral alumni of the Post Graduate Program in Management (PPGA) at the Federal University of Rio Grande do Norte (UFRN). The operationalization of the research´s main objective was possible through the specific objectives: characterize graduate profile as CAPES Journal Portal users b) identify motivation for the use of CAPES Journal Portal c) detect graduate satisfaction degree in information seeking done at CAPES Journal Portal d) verify graduate satisfaction regarding the use of the CAPES Journal Portal e) verify the use of the information that is obtained by graduates in the development of their academic activities. The research is of descriptive nature employing a mixed methodological strategy in which quantitative approach predominates. Data collection was done through a web survey questionnaire. Quantitative data analysis was made possible through the use of a statistical method. As for qualitative analysis, there was use of the Brenda Dervin´s sense-making approach as well as content analysis in open ended questions. The research samples were composed by 90 graduate students who had defended their dissertation/thesis in the PPGA program at UFRN in the time span of 2010-2013. This represented by 88% of this population. As for user profile, the analysis has made evident that there are no quantitative differences related to gender. There is predominance of male graduates that were aged 26 to 30 years old. As for female graduates, the great majority were 31 o 35 years old. Most graduates had Master´s degree scholarship in order to support their study. It was also seen that the great majority claim to use the Portal during their post graduation studies. The main reasons responsible for non use was: preference for the use of other data bases and lack of knowledge regarding the Portal. It was observed that the most used information resources were theses and dissertations. Data also indicate preference for complete text. Those who have used the Portal also claimed to have used other electronic information fonts in order to fulfill their information needs. The information fonts that were researched outside in the Portal were monographs, dissertations and thesis. Scielo was the most used information font. Results reveal that access and use of the Portal has been done in a regular manner during post graduation studies. But on the other hand, graduates also make use of other electronic information fonts in order to meet their information needs. The study also confirmed the important mission performed by the Portal regarding Brazilian scientific communication production. This was seen even though users have reported the need for improvement in some aspects such as: periodic training in order to promote, encourage and teach more effective use of the portal; investment aiming the expansion of Social Sciences Collection in the Portal as well as the need to implement continuous evaluation process related to user satisfaction in regarding the services provided.

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A Internet possui inúmeros tipos de documentos e é uma influente fonte de informação.O conteúdo Web é projetado para os seres humanos interpretarem e não para as máquinas.Os sistemas de busca tradicionais são imprecisos na recuperação de informações. Ogoverno utiliza e disponibiliza documentos na Web para que os cidadãos e seus própriossetores organizacionais os utilizem, porém carece de ferramentas que apoiem na tarefa darecuperação desses documentos. Como exemplo, podemos citar a Plataforma de CurrículosLattes administrada pelo Cnpq.A Web semântica possui a finalidade de otimizar a recuperação dos documentos, ondeesses recebem significados, permitindo que tanto as pessoas quanto as máquinas possamcompreender o significado de uma informação. A falta de semântica em nossos documentos,resultam em pesquisas ineficazes, com informações divergentes e ambíguas. Aanotação semântica é o caminho para promover a semântica em documentos.O objetivo da dissertação é montar um arcabouço com os conceitos da Web Semânticaque possibilite anotar automaticamente o Currículo Lattes por meio de bases de dadosabertas (Linked Open Data), as quais armazenam o significado de termos e expressões.O problema da pesquisa está baseado em saber quais são os conceitos associados à WebSemântica que podem contribuir para a Anotação Semântica Automática do CurrículoLattes utilizando o Linked Open Data (LOD)?Na Revisão Sistemática da Literatura foi apresentado conceitos (anotação manual, automática,semi-automática, anotação intrusiva...), ferramentas (Extrator de Entidade...)e tecnologias (RDF, RDFa, SPARQL..) relativas ao tema. A aplicação desses conceitosoportunizou a criação do Sistema Lattes Web Semântico. O sistema possibilita a importaçãodo currículo XML da Plataforma Lattes, efetua a anotação automática dos dadosdisponibilizados utilizando as bases de dados abertas e possibilita efetuar consultas semânticas.A validação do sistema é realizada com a apresentação de currículos anotados e a realizaçãode consultas utilizando dados externos pertencentes ao LOD. Por fim é apresentado asconclusões, dificuldades encontradas e proposta de trabalhos futuros.