998 resultados para VELASCO


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Occupational exposure to respirable crystalline silica and to radiation emitted by natural radionuclides present both in rocks and sands was studied in the Brazilian extractive process and granite product manufacture. Respirable airborne dust samples were collected in working environments, where workers perform different tasks with distinct commercial granites types, and also in places where sandblasters work with sands from different origins. The free crystalline silica contents were determined using X-ray diffraction of the respirable particulate fraction of each sample. Dust samples from granite cutting and sandblasting ambient had the natural radionuclides concentrations measured by gamma spectrometry. Dust concentrations in the workplaces were quite variable, reaching values up to 10 times higher than the respirable particle mass threshold limit value (TLV) set by the American Conference for Governmental Industrial Hygienists of 3 mg m(-3). Also the free crystalline silica concentrations were high. reaching values up to 48 times the TLV of 0.025 mg m(-3). Additionally, our results suggest that the risk of radiation-induced cancer in the granite or marble industries is negligible. However, the combined exposure to dust, gamma radiation, and radon daughter products could result in the enhancement of lung cancer risks associated to sandblasting activities. (C) 2010 Elsevier Ltd. All rights reserved.

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Radon and gamma radiation level measurements were carried out inside the La Carolina mine, one of the oldest gold mining camps of southern South America, which is open for touristic visits nowadays. CR-39 track-etch detectors and thermoluminescent dosimeters of natural CaF(2) and LiF TLD-100 were exposed at 14 points along the mine tunnels in order to estimate the mean (222)Rn concentration and the ambient dose equivalent during the summer season (November 2008 to February 2009). The values for the (222)Rn concentration at each monitoring site ranged from 1.8 +/- 0.1 kBq m(-3) to 6.0 +/- 0.5 kBq m(-3), with a mean value of 4.8 kBq m(-3), indicating that these measurements exceed in about three times the upper action level recommended by ICRP for workplaces. The correlations between radon and gamma radiation levels inside the mine were also investigated. Effective doses due to (222)Rn and gamma rays inside the mine were determined, resulting in negligible values to tourists. Considering the effective dose to the mine tourist guides, values exceeding 20 mSv of internal contribution to the effective doses can be reached, depending on the number of working hours inside the mine. (C) 2009 Elsevier Ltd. All rights reserved.

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We studied the P-T-t evolution of a mid-crustal igneous-metamorphic segment of the Famatinian Belt in the eastern sector of the Sierra de Velasco during its exhumation to the upper crust. Thermobarometric and geochronological methods combined with field observations permit us to distinguish three tectonic levels. The deepest Level I is represented by metasedimentary xenoliths and characterized by prograde isobaric heating at 20-25 km depth. Early/Middle Ordovician granites that contain xenoliths of Level I intruded in the shallower Level II. The latter is characterized by migmatization coeval with granitic intrusions and a retrograde isobaric cooling P-T path at 14-18 km depth. Level II was exhumed to the shallowest supracrustal Level III, where it was intruded by cordierite-bearing granites during the Middle/Late Ordovician and its host-rock was locally affected by high temperature-low pressure HT/LP metamorphism at 8-10 km depth. Level III was eventually intruded by Early Carboniferous granites after long-term slow exhumation to 6-7 km depth. Early/Middle Ordovician exhumation of Level II to Level III (Exhumation Period I,0.25-0.78 mm/yr) was faster than exhumation of Level III from the Middle/Late Ordovician to the Lower Carboniferous (Exhumation Period II, 0.01-0.09 mm/yr). Slow exhumation rates and the lack of regional evidence of tectonic exhumation suggest that erosion was the main exhumation mechanism of the Famatinian Belt. Widespread slow exhumation associated with crustal thickening under a HT regime suggests that the Famatinian Belt represents the middle crust of an ancient Altiplano-Puna-like orogen. This thermally weakened over-thickened Famatinian crust was slowly exhumed mainly by erosion during similar to 180 Myr. (C) 2010 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.

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The Santa Rosa and Sauce Guacho plutons are two post-collisional peraluminous Late Devonian to Early Carboniferous leucogranites that intruded the banded schists of the Ancasti Formation. The leucogranites are composed of microcline phenocrysts along with quartz, plagioclase, muscovite, biotite, ilmenite, tourmaline, apatite, monazite and zircon. Their geochemical composition is consistent with S-type granites and mineralogically they belong to MPG granites (muscovite-peraluminous granites). It is proposed that granite magma generation was related to shear zones that concentrated fluids in the metasedimentary crust during a collision or transcurrent tectonics. U-Pb analyses on monazite gave an age of 369.8 +/- 5.3 Ma, while Sm/Nd isotopic data yield epsilon(Nd(t)) values of -5.3 for Sauce Guacho and -5.7 for Santa Rosa indicating crustal provenance. Nd model ages between 1,544 and 1,571 Ma are within the range of magmatic rocks from the Lower Ordovician Famatinian Arc in the Central Sierras Pampeanas.

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The paper analyses empirical performance data of five commercial PV-plants in Germany. The purpose was on one side to investigate the weak light performance of the different PV-modules used. On the other hand it was to quantify and compare the shading losses of different PV-array configurations. The importance of this study relies on the fact that even if the behavior under weak light conditions or the shading losses might seem to be a relatively small percentage of the total yearly output; in projects where a performance guarantee is given, these variation can make the difference between meeting or not the conditions.When analyzing the data, a high dispersion was found. To reduce the optical losses and spectral effects, a series of data filters were applied based on the angle of incidence and absolute Air Mass. To compensate for the temperature effects and translate the values to STC (25°C), five different methods were assessed. At the end, the Procedure 2 of IEC 60891 was selected due to its relative simplicity, usage of mostly standard parameters found in datasheets, good accuracy even with missing values, and its potential to improve the results when the complete set of inputs is available.After analyzing the data, the weak light performance of the modules did not show a clear superiority of a certain technology or technology group over the others. Moreover, the uncertainties in the measurements restrictive the conclusiveness of the results.In the partial shading analysis, the landscape mounting of mc-Si PV-modules in free-field showed a significantly better performance than the portrait one. The cross-table string using CIGS modules did not proved the benefits expected and performed actually poorer than a regular one-string-per-table layout. Parallel substrings with CdTe showed a proper functioning and relatively low losses. Among the two product generations of CdTe analyzed, none showed a significantly better performance under partial shadings.

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A common problem when planning large free field PV-plants is optimizing the ground occupation ratio while maintaining low shading losses. Due to the complexity of this task, several PV-plants have been built using various configurations. In order to compare the shading losses of different PV technologies and array designs, empirical performance data of five free field PV-plants operating in Germany was analyzed. The data collected comprised 140 winter days from October 2011 until March 2012. The relative shading losses were estimated by comparing the energy output of selected arrays in the front rows (shading-free) against that of shaded arrays in the back rows of the same plant. The results showed that landscape mounting with mc-Si PV-modules yielded significantly better results than portrait one. With CIGS modules, making cross-table strings using the lower modules was not beneficial as expected and had more losses than a one-string-per-table layout. Parallel substrings with CdTe showed relatively low losses. Among the two CdTe products analyzed, none showed a significantly better performance.

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Forest nurseries are essential for producing good quality seedlings, thus being a key element in the reforestation process. With increasing climate change awareness, nursery managers are looking for new tools that can help reduce the effects of their operations on the environment. The ZEPHYR project, funded by the European Commission under the Seventh Framework Programme (FP7), has the objective of finding new alternatives for nurseries by developing innovative zero-impact technologies for forest plant production. Due to their direct relationship to the energy consumption of the nurseries, one of the main elements addressed are the grow lights used for the pre-cultivation. New LED luminaires with a light spectrum tailored to the seedlings’ needs are being studied and compared against the traditional fluorescent lamps. Seedlings of Picea abies and Pinus sylvestris were grown under five different light spectra (one fluorescent and 4 LED) during 5 weeks with a photoperiod of 16 hours at 100 μmol∙m-2∙s-1 and 60% humidity. In order to evaluate if these seedlings were able cope with real field stress conditions, a forest field trial was also designed. The terrain chosen was a typical planting site in mid-Sweden after clear-cutting. Two vegetation periods after the outplanting, the seedlings that were pre-cultivated under the LED lamps have performed at least as well as those that were grown under fluorescent lights. These results show that there is a good  potential for lightning substitution in forestry nurseries.

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Los modelos de anàlisis de la politica social en cuanto a los determinantes de su formulación, ejecución y efecto en la sociedad y en el Estado, nos llevan a af irmar que este hecho aún es nuevo en la que podria llamarse corriente politica de la salud colectiva. En efecto, el avance realizado en la última década por los grupos de analistas de la salud que teóricas para repensar y profundizar en proceso salud enfermedad, ha comenzado últimos a~os una mayor atención a los ideolÓgicos de la politica de salud determinados proyectos históricos y administrativas estatales. aportaron categorias los determinantes deI a plantear en los elementos politicoy su relaciÓn con formas politico- Siendo asi, los ej es metodol óg i cos es tàn siendo buscados, en miras a construir una teoria que permita llegar, a través deI estudio de los casos nacionales, a una comprensión deI Estado desde la salud. Este trabajo intenta demostrar la posibilidad de una propuesta metodológica sobre las instituciones de salud en el Ecuador; a través de tres ejes fundamentales: los actores políticos; la capacidad deI régimen politico de replantear el papel deI Estado institucional, el proyecto politico y la formulación y cosificación de la politica de salud en instituciones. Parte de una búsqueda de elementos teóricos que permitan construir una explicación de la institucionalización de salud, se detiene a esquematizar la propuesta metodológica para finalmente analizar los hallazgos a los que ésta le ha llevado.

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O objetivo desse estudo é analisar se diferentes órgãos do Ministério Público brasileiro estão cumprindo com a Lei de Acesso à Informação adequadamente, tendo por base a metodologia de avaliação de transparência passiva desenvolvida pelo Programa de Transparência Pública da FGV. A equipe de pesquisadores envolvida neste projeto enviou 193 pedidos de acesso à informação para 29 diferentes órgãos do Ministério Público, sendo 3 órgãos do Ministério Público da União – o Ministério Público Federal (MPF), o Ministério Público do Trabalho (MPT) e o Ministério Público do Distrito Federal e Territórios (MPDFT) – além de 26 órgãos do Ministério Público Estadual. Os pedidos de acesso à informação enviados focavam em temas relevantes para uma análise do grau de transparência do MP, dentre os quais: a remuneração de promotores e procuradores de justiça, a existência de mecanismos de prevenção de nepotismo e os critérios de promoção dos membros do MP. Com esses temas em vista, o presente trabalho busca contribuir para a promoção de melhores práticas de transparência dentro dos órgãos do Ministério Público, tendo como diretriz a aproximação, na medida do possível, de um quadro ideal de acesso à informação.

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Qual o impacto dos escândalos políticos sobre o clima econômico dos países sul-americanos? O presente trabalho busca responder essa pergunta ao avaliar a confiança de especialistas na economia de sete países sul-americanos durante a ocorrência de escândalos políticos em um recorte temporal de 10 anos (de 2005 até 2014). Entendemos os escândalos políticos como sendo eventos noticiados pela mídia envolvendo os presidentes das repúblicas sul-americanas em episódios de corrupção ou abuso de poder. Já o clima econômico é medido a partir da avaliação da economia por especialistas regularmente consultados pela Sondagem Econômica da América Latina, uma pesquisa que gera a construção do Índice de Clima Econômico da América Latina. Evidências apontam a influência de determinantes políticos sobre a avaliação econômica realizada pelo público geral. Poucos estudos exploram o processo de formação da confiança econômica de especialistas. Utilizamos o modelo de regressão em painel para verificar a correlação entre escândalos políticos e o Índice de Clima Econômico. Nenhuma correlação pôde ser verificada quando adotamos um modelo relacionado à economia internacional. Surpreendentemente, encontramos uma correlação significante e positiva quando adicionamos variáveis econômicas domésticas à análise. Acreditamos que futuras contribuições para o tema devam levar em conta a importância do papel das instituições como elemento fundamental na confiança de especialistas.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Purpose: To describe spontaneous blink kinematics in Graves' upper eyelid retraction (UER).Methods: The magnetic search coil technique was used to record spontaneous blinks of 15 healthy subjects (aged 23-56 years, 15 eyelids) and 15 patients with Graves' UER (aged 22-62 years, 15 eyelids) during a 5-min period of video observation, and the signals were digitized at 200 Hz (12 bits). Overall, a total of 2,798 blinks were recorded for the controls and 1,860 for the patients. The distance between pupil center and upper eyelid margin in the primary position of gaze (MRD) was measured with the Image J software.Results: The blinking rate of patients was lower than that of control subjects, with a mean (+/-SEM) blinking rate (blinks/min) of 13.0 +/- 1.7 for patients and of 20.0 +/- 2.1 for the controls (t = 2.58, P = 0.016). There were no statistically significant differences in blink amplitude between controls (22.7 +/- 3.1 degrees) and Graves' patients (24.7 +/- 3.3 degrees). However, while only 22% of the blinks performed by controls were smaller than MRD, this rate was 78% for patients. In addition, in blinks larger than 25, patients showed lower down-phase velocity than controls.Conclusions: Patients with Graves' UER show reduced blinks rates and abnormal blink kinematics, which might be related to the development of exposure keratitis in this disease.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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OBJETIVO: Avaliar quantitativamente as mudanças da posição palpebral e as medidas da fenda palpebral de indivíduos acima dos 50 anos. MÉTODOS: Estudo observacional, tendo sido avaliados 325 indivíduos, com idade acima de 50 anos, segundo distância intercantal, largura e altura da fenda palpebral, ângulo palpebral externo e interno, distância entre o reflexo pupilar e a margem da pálpebra superior (distância reflexo-margem) e a área total da fenda palpebral. Utilizou-se filmadora Sony Lithium para obtenção das imagens digitais, com o indivíduo fixando um objeto a 1 metro de distância, sendo as imagens transferidas posteriormente para computador McIntosh G4 e processadas pelo programa NIH 1.58. Os dados foram submetidos à análise estatística. RESULTADOS: Os participantes apresentavam dermatocálase (96,5%), ptose do supercílio (60,8%), prolapso de gordura orbital (50,0%) ou ptose palpebral (39,1%). As alterações foram bilaterais em 68,8% dos indivíduos. A distância intercantal aumentou com a idade; a largura da fenda palpebral, a distância reflexo-margem e a medida do ângulo externo diminuíram nos mais idosos. As diferenças foram mais significativas quando os olhos foram estudados separadamente. CONCLUSÃO: A distância intercantal aumenta, ao passo que a largura da fenda palpebral, a distância reflexo-margem e a área total da fenda palpebral diminuem com o aumento da idade.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)