982 resultados para 1530


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Este trabalho investigativo teve como objeto a avaliação institucional e auto-avaliação enquanto instrumentos inseridos no Sistema Nacional de Avaliação do Ensino Superior e concebidos no âmbito das Políticas Públicas de Avaliação consolidadas no Brasil na década 90. O objetivo central foi de identificar os sentidos que a avaliação institucional e a auto-avaliação têm para os professores do Centro Universitário Senac de São Paulo. A hipótese, construída durante a investigação é que o docente não estabelece relações diretas e imediatas entre seu trabalho cotidiano na escola e nos estágios e s processos de avaliação institucional e auto-avaliação do qual participa. O estudo situa-se num contexto do ensino superior no Brasil em que a temática da avaliação adquiriu relevância e centralidade. Contexto de mudança no sistema capitalista, de revisão do papel do Estado, de difusão do neoliberalismo e de busca de maior controle e regulação do Sistema de ensino Superior. A metodologia escolhidos para colher os dados foram: a entrevista reflexiva realizada de forma aberta e semi-estruturada; fontes documentais e históricas da instituição; fontes bibliográficas; observações feitas na instituição. O trabalho de campo foi realizado junto ao Curso de Hotelaria, do Centro Universitário Senac/SP, instituição particular de ensino superior. Os resultados apontaram para um professor que não estabelece relações diretas e imediatas entre seu trabalho cotidiano e os processos de avaliação institucional nem as relações desta com a auto-avaliação da qual participa. Isto não significa que haja uma visão ingênua do mesmo da ação avaliativa institucional. Observou-se que o nível de participação dos professores nestes processos é muito mais na execução do que na concepção dos mesmos não sendo o processo de avaliação institucional acompanhado de um aprimoramento dos canais participativos para a vida acadêmica

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A separation technique employing a microfabricated sieve has been demonstrated by observing the motion of DNA molecules of different size. The sieve consists of a two-dimensional lattice of obstacles whose asymmetric disposition rectifies the Brownian motion of molecules driven through the device, causing them to follow paths that depend on their diffusion coefficient. A nominal 6% resolution by length of DNA molecules in the size range 15–30 kbp may be achieved in a 4-inch (10-cm) silicon wafer. The advantage of this method is that samples can be loaded and sorted continuously, in contrast to the batch mode commonly used in gel electrophoresis.

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Multiple-complete-digest mapping is a DNA mapping technique based on complete-restriction-digest fingerprints of a set of clones that provides highly redundant coverage of the mapping target. The maps assembled from these fingerprints order both the clones and the restriction fragments. Maps are coordinated across three enzymes in the examples presented. Starting with yeast artificial chromosome contigs from the 7q31.3 and 7p14 regions of the human genome, we have produced cosmid-based maps spanning more than one million base pairs. Each yeast artificial chromosome is first subcloned into cosmids at a redundancy of ×15–30. Complete-digest fragments are electrophoresed on agarose gels, poststained, and imaged on a fluorescent scanner. Aberrant clones that are not representative of the underlying genome are rejected in the map construction process. Almost every restriction fragment is ordered, allowing selection of minimal tiling paths with clone-to-clone overlaps of only a few thousand base pairs. These maps demonstrate the practicality of applying the experimental and software-based steps in multiple-complete-digest mapping to a target of significant size and complexity. We present evidence that the maps are sufficiently accurate to validate both the clones selected for sequencing and the sequence assemblies obtained once these clones have been sequenced by a “shotgun” method.

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We have spectroscopically determined breath ammonia levels in seven patients with end-stage renal disease while they were undergoing hemodialysis at the University of California, Los Angeles, dialysis center. We correlated these measurements against simultaneously taken blood samples that were analyzed for blood urea nitrogen (BUN) and creatinine, which are the accepted standards indicating the level of nitrogenous waste loading in a patient's bloodstream. Initial levels of breath ammonia, i.e., at the beginning of dialysis, are between 1,500 ppb and 2,000 ppb (parts per billion). These levels drop very sharply in the first 15–30 min as the dialysis proceeds. We found the reduction in breath ammonia concentration to be relatively slow from this point on to the end of dialysis treatment, at which point the levels tapered off at 150 to 200 ppb. For each breath ammonia measurement, taken at 15–30 min intervals during the dialysis, we also sampled the patient's blood for BUN and creatinine. The breath ammonia data were available in real time, whereas the BUN and creatinine data were available generally 24 h later from the laboratory. We found a good correlation between breath ammonia concentration and BUN and creatinine. For one of the patients, the correlation gave an R2 of 0.95 for breath ammonia and BUN correlation and an R2 of 0.83 for breath ammonia and creatinine correlation. These preliminary data indicate the possibility of using the real-time breath ammonia measurements for determining efficacy and endpoint of hemodialysis.

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I. Título Las culturas políticas en Perú. El caso de Lima II. Objetivos 1. Objetivo General Los propósitos de esta investigación consisten en identificar las subculturas políticas existentes en Lima, la capital de Perú, y comprender sus rasgos distintivos desde el punto de vista de las actitudes sociales y políticas, los valores y las variables socioeconómicas y demográficas. 2. Objetivos Específicos Estos objetivos se centran en las principales características de la cultura política en Lima, tomando en consideración los cuatro factores explicativos de la cultura política propuestos por Morán y Benedicto (1995), a saber, el papel del ciudadano como actor, la vinculación del ciudadano con la política, las creencias y actitudes hacia el sistema político, y las actitudes hacia el Estado y el gobierno. A las variables antes mencionadas, se suma la comprensión de los diferentes tipos de subculturas políticas en el área metropolitana de Lima, haciendo hincapié en las características y significado de estas últimas. III. Métodos y técnicas de investigación La investigación contempla un estudio cualitativo y otro de índole cuantitativa. En el primero se desarrollaron ocho dinámicas grupales con mujeres y hombres de 18 a 55 años correspondientes a cinco niveles socioeconómicos. En el segundo estudio se realizaron, para la encuesta de naturaleza cuantitativa, 1530 entrevistas estandarizadas a mujeres y hombres de 18 a 80 años correspondientes a los cinco niveles socioeconómicos antes citados. Este segundo estudio permitió llevar a cabo un análisis multivariado para identificar las dimensiones de la cultura política en el área metropolitana de Lima y proceder a la comprobación de la existencia de cuatro tipos diversos de subculturas políticas existentes en este contexto urbano...

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La Malinche’s serene face and beautifully dressed figure dominates the first half of the lost sixteenth century manuscript El Lienzo de Tlaxcala, which exists today in the form of a copy made after the original. In this paper I propose an expanded study of these twenty-one representations of La Malinche as they offer insight into the Tlaxcalan’s reverence, respect, and spiritual belief in La Malinche. The Tlaxcalan leaders recognized her influence on both the Spanish and indigenous leaders during the conquest and cleverly designed a painted narrative to reinforce their connection with La Malinche to enhance their position with the Spanish. Through a multi layered study that consists of a detailed account of her biography in contrast to gender roles in Pre-Hispanic America, as well as formal and iconographic analysis of rarely examined images from the Lienzo de Tlaxcala that link La Malinche to the Virgin Mary, and a review of the ethnographic research on religious beliefs among contemporary Tlaxcalans, I will demonstrate that the mutable history of this woman made her the ideal supernatural protagonist for the people of Tlaxcala.

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Calcineurin (protein phosphatase 2B) (CN) comprises a family of serine/threonine phosphatases that play a pivotal role in signal transduction cascades in a variety of cells, including neutrophils. Angiotensin II (Ang II) increases both activity and de novo synthesis of CN in human neutrophils. This study focuses on the role that intracellular redox status plays in the induction of CN activity by Ang II. Both de novo synthesis of CN and activity increase promoted by Ang II were downregulated when cells were treated with l-buthionine-(S,R)-sulfoximine, an inhibitor of synthesis of the antioxidant glutathione. We have also investigated the effect of pyrrolidine dithiocarbamate and phenazine methosulfate, which are antioxidant and oxidant compounds, respectively, and concluded that the intracellular redox status of neutrophils is highly critical for Ang II-induced increase of CN expression and activity. Results obtained in neutrophils from hypertensive patients were very similar to those obtained in these cells on treatment with Ang II. We have also addressed the possible functional implication of CN activation in the development of hypertension. Present findings indicate that downregulation of hemoxygenase-1 expression in neutrophils from hypertensive subjects is likely mediated by CN, which acts by hindering translocation to the nucleus of the transcription factor NRF2. These data support and extend our previous results and those from other authors on modulation of CN expression and activity levels by the intracellular redox status.

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Purpose: Regulation of liver X receptors (LXRs) is essential for cholesterol homeostasis and inflammation. The present study was conducted to determine whether oleic acid (OA) could regulate mRNA expression of LXRα and LXRα-regulated genes and to assess the potential promotion of oxidative stress by OA in neutrophils. Methods: Human neutrophils were treated with OA at different doses and LXR target gene expression, oxidative stress production, lipid efflux and inflammation state were analyzed. Results: We describe that mRNA synthesis of both LXRα and ABCA1 (a reverse cholesterol transporter) was induced by OA in human neutrophils. This fatty acid enhanced the effects of LXR ligands on ABCA1 and LXR expression, but it decreased the mRNA levels of sterol regulatory element-binding protein 1c (a transcription factor that regulates the synthesis of triglycerides). Although OA elicited a slight oxidative stress in the short term (15–30 min) in neutrophils, it is unlikely that this is relevant for the modulation of transcription in our experimental conditions, which involve longer incubation time (i.e., 6 h). Of physiological importance is our finding that OA depresses intracellular lipid levels and that markers of inflammation, such as ERK1/2 and p38 mitogen-activated protein kinase phosphorylation, were decreased by OA treatment. In addition, 200 μM OA reduced the migration of human neutrophils, another marker of the inflammatory state. However, OA did not affect lipid peroxidation induced by pro-oxidant agents. Conclusions: This work presents for the first time evidence that human neutrophils are highly sensitive to OA and provides novel data in support of a protective role of this monounsaturated acid against the activation of neutrophils during inflammation.

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We quantify the rate and efficiency of picosecond electron transfer (ET) from PbS nanocrystals, grown by successive ionic layer adsorption and reaction (SILAR), into a mesoporous SnO2 support. Successive SILAR deposition steps allow for stoichiometry- and size-variation of the QDs, characterized using transmission electron microscopy. Whereas for sulfur-rich (p-type) QD surfaces substantial electron trapping at the QD surface occurs, for lead-rich (n-type) QD surfaces, the QD trapping channel is suppressed and the ET efficiency is boosted. The ET efficiency increase achieved by lead-rich QD surfaces is found to be QD-size dependent, increasing linearly with QD surface area. On the other hand, ET rates are found to be independent of both QD size and surface stoichiometry, suggesting that the donor–acceptor energetics (constituting the driving force for ET) are fixed due to Fermi level pinning at the QD/oxide interface. Implications of our results for QD-sensitized solar cell design are discussed.

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Both spin and orbital degrees of freedom contribute to the magnetic moment of isolated atoms. However, when inserted in crystals, atomic orbital moments are quenched because of the lack of rotational symmetry that protects them when isolated. Thus, the dominant contribution to the magnetization of magnetic materials comes from electronic spin. Here we show that nanoislands of quantum spin Hall insulators can host robust orbital edge magnetism whenever their highest occupied Kramers doublet is singly occupied, upgrading the spin edge current into a charge current. The resulting orbital magnetization scales linearly with size, outweighing the spin contribution for islands of a few nm in size. This linear scaling is specific of the Dirac edge states and very different from Schrodinger electrons in quantum rings. By modeling Bi(111) flakes, whose edge states have been recently observed, we show that orbital magnetization is robust with respect to disorder, thermal agitation, shape of the island, and crystallographic direction of the edges, reflecting its topological protection.

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La condición tridimensional de la construcción edificatoria precisa del uso del dibujo en 3D como la mejor herramienta de proyecto y transmisión de conocimientos técnicos y formales. El objetivo de esta comunicación es mostrar la aplicación de la expresión gráfica en 3D en un análisis histórico sobre la evolución de la envolvente industrializada en arquitectura, identificando sus principales condicionantes técnicos y constructivos. El estudio compara la evolución del uso de sistemas constructivos industrializados mediante un análisis gráfico de las soluciones constructivas más destacables. La metodología empleada se basa en la identificación y estudio de determinados sistemas constructivos industrializados compuestos por materiales ligeros así como de obras de arquitectura representativas por su influencia en la evolución de la envolvente arquitectónica en la segunda mitad del siglo XX. La representación gráfica en 3D ayuda a comparar las obras analizadas desde aspectos tecnológicos y formales, constatándose la utilidad del dibujo asistido por ordenador en el análisis constructivo realizado. En conclusión, el uso del dibujo arquitectónico en 3D contribuye, por la mejor comprensión de las características espaciales de las soluciones constructivas, al análisis de las propiedades materiales y funcionales de los sistemas constructivos industrializados y su aplicación al diseño arquitectónico, ayudando a perfeccionar su conocimiento e incrementando la calidad constructiva y compromiso social de las propuestas arquitectónicas.

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The inelastic portion of the tunnel current through an individual magnetic atom grants unique access to read out and change the atom’s spin state, but it also provides a path for spontaneous relaxation and decoherence. Controlled closure of the inelastic channel would allow for the latter to be switched off at will, paving the way to coherent spin manipulation in single atoms. Here, we demonstrate complete closure of the inelastic channels for both spin and orbital transitions due to a controlled geometric modification of the atom’s environment, using scanning tunneling microscopy (STM). The observed suppression of the excitation signal, which occurs for Co atoms assembled into chains on a Cu2N substrate, indicates a structural transition affecting the dz2 orbital, effectively cutting off the STM tip from the spin-flip cotunneling path.

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This layer is a georeferenced raster image of the historic paper map entitled: Trigonometrical survey of the Maldive Islands, by Commander R. Moresby, assisted by Lieut. F.T. Powell, Indian Navy ; additions and corrections by Professor A. Agassiz, Mr. Stanley Gardiner and Mr. L. A. Molony, 1902 ; eng. by J. & C. Walker. Sheet 3. It was published by Hydrographic Office, 1904. Scale [ca. 1:310,000]. This layer is image 3 of 3 total images of the three sheet source map representing the southern portion of the map. The image inside the map neatline is georeferenced to the surface of the earth and fit to the 'Mercator' projection. All map collar and inset information is also available as part of the raster image, including any inset maps, profiles, statistical tables, directories, text, illustrations, index maps, legends, or other information associated with the principal map. This map shows features such as drainage, human settlements, ground cover, shoreline features, inlets, lagoons, shoals, sand banks, atolls, islands and islets, points, rocks, bottom types, and more. Relief shown by spot heights. Depths shown by soundings. Includes notes on navigation and locations of potable water. This layer is part of a selection of digitally scanned and georeferenced historic maps from the Harvard Map Collection and the Harvard University Library as part of the Open Collections Program at Harvard University project: Organizing Our World: Sponsored Exploration and Scientific Discovery in the Modern Age. Maps selected for the project correspond to various expeditions and represent a range of regions, originators, ground condition dates, scales, and purposes.

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Dissertação de mestrado na área de Educação Social e Intervenção Comunitária