348 research outputs found

    O lineamento transbrasiliano na Bacia do Paraná : compartimentação crustal do embasamento e reativações fanerozóicas

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    Tese (doutorado)—Universidade de Brasília, Instituto de Geociências, 2015.A Plataforma Sul Americana inclui dois importantes componentes geológicos de escala continental e com raízes estruturais em comum: o Lineamento Transbrasiliano (LTB) e a Bacia do Paraná. Importante relação entre os dois ocorre na região entre o Arco Magmático de Goiás e a Faixa Paraguai, que impõem particularidades estruturais obscurecidas pela cobertura sedimentar da Bacia do Paraná. A área, alvo desse estudo, é recoberta por dados aerogeofísicos, magnéticos e gravimétricos, adquiridos com diferentes resoluções. Sua integração permitiu gerar mapas de anomalias magnéticas e anomalias Bouguer, este incluindo dados terrestres.Técnicas de processamento e modelagem geofísica foram utilizadas com objetivo de esclarecer a disposição de compartimentos crustais e estruturas do embasamento da bacia em diferentes níveis de profundidade. Três grandes descontinuidades magnéticas do LTB limitam compartimentos crustais na área, de leste para oeste: lineamentos Serra Negra, Baliza e General Carneiro, com direções gerais N30°E, N60°E e N70°E, respectivamente, que separam mudanças significativas no background gravimétrico, ainda subdividido por lineamento adicional N50°W, São Vicente. Análise de lineamentos de 1ª, 2ª e 3ª ordens aponta a predominância de orientações NE, interpretadas como originalmente brasilianas e reativadas no Jurássico-Cretáceo, e direções NW, bem marcadas nas unidades sedimentares da bacia e com caráter distensivo, atribuído a reativação mesozóica. Análise do matched-filter aplicada a dados magnéticos e gravimétricos, com suporte da deconvolução de Euler e tilt-depth, aponta estimativas de profundidades importantes: (i) 2,5 km, relacionado ao topo do embasamento da Bacia do Paraná; (ii) 6 km, atribuído ao topo do embasamento da bacia neoproterozóica (Grupo Cuiabá); (iii) 20 km, possivelmente associado à interface crosta superior/inferior; e (iv) 33-39 e 43 km, relativos às espessuras crustais a oeste e sudeste do lineamento Serra Negra, respectivamente. A crosta a leste é formada pelo o Arco Magmático de Arenópolis e o limite noroeste do Bloco Paranapanema e a oeste é constituída por zona de transição crustal e o paleocontinente Amazônico. A modelagem geofísica conjunta 2D com dados gravimétricos e magnéticos esclarece a geometria assimétrica do embasamento da bacia, configurando pelo menos três meiográbens formados ao longo de estruturas reativadas do LTB. A região entre os lineamentos Serra Negra e General Carneiro caracteriza-se por menor espessura e maior fraqueza crustal, onde importantes estruturas se desenvolveram no Mesozóico: desde reativações com direção NW, vinculadas a soerguimento crustal e à implantação de pequenas bacias cretáceas alinhadas a NE. Dois depocentros importantes ocorrem: a norte do lineamento General Carneiro, com direção N70°E, e a leste da falha Serra Negra, com direção N30°E – NS.The South American Platform includes two major geological components of continental scale with common structural roots: the Transbrasiliano Lineament (LTB) and the Paraná Basin. An important relationship between the two is observed in the region between the Goiás Magmatic Arc and the Paraguay Belt, which impose structural features concealed by the sedimentary cover of the Paraná Basin. This region comprises our study area, and is covered by airborne magnetic and gravity surveys, acquired with different resolutions. These data were integrated to generate maps of magnetic and Bouguer anomalies, the latter included ground data. Data processing and geophysical modeling techniques were used in order to reveal the disposition of crustal compartments and the basin basement structures at different depths. Three large magnetic discontinuities limit crustal compartments in the area, from east to west: Serra Negra, Baliza and General Carneiro lineaments, with N30°E, N60°E and N70°E trending alignments, respectively, which separate significant changes in the gravity background, still subdivided by the additional Sao Vicente lineament, N50°W. Analyses of 1st, 2nd and 3rd order lineaments indicate predominance of NE trending directions, which were interpreted as Brasiliano structures, reactivated in the Jurassic-Cretaceous. NW directions, well-marked in the sedimentary units of the basin and with extensional character, were attributed to Mesozoic reactivation. Matched-filter analysis applied to magnetic and gravity data, supported by the Euler deconvolution and tiltdepth, yielded important depths estimates: (i) 2.5 km to the top of the Paraná Basin basement; (ii) 6 km to the top of the Neoproterozoic Basin basement (Cuiabá Group); (iii) 20 km, possibly associated with the upper/lower crust interface; and (iv) 33-39 and 43 km related to crustal thicknesses west and southeast of the Serra Negra lineament, respectively. To the east, the crust is formed by the Arenópolis Magmatic Arc and the northwest boundary of Paranapanema Block, while to the west it consists of a crustal transition zone and the Amazon paleocontinent. The 2D geophysical modeling based on gravity and magnetic data sheds light on the asymmetric geometry of the basement of the basin, with at least three half-grabens formed by LTB reactivated structures. The region between the Serra Negra and General Carneiro lineaments is characterized by thinner crust and higher crustal weakness, where important structures have developed in the Mesozoic, including NW trending reactivations, linked to crustal uplift and deployment of small NE-aligned Cretaceous basins. Important depocenters occur: the first, to the north of General Carneiro lineament, and the second, to the east of the Serra Negra fault, with N70ºE and N30°E – NS trending directions, respectively

    The Geomagnetic Field Transformants and Their Complexing with Data of Gravitational, Thermal and Radioactive Fields: During the Exploration of Hydrocarbon Fields at the Southern Part of the Ustyurt Region

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    The chapter discusses the results of the interpretation of aeromagnetic survey data in the southern part of the Ustyurt region in order to identify zones that are heterogeneous in magnetic properties, with their subsequent tie-up with areas promising for the detection of hydrocarbon accumulations. Three tectonic elements are distinguished—the Central Ustyurt system of disturbances, the Shakhpakhty step and the Assakeaudan depression according to the sign, orientation and quantitative values of the transformants of the geomagnetic field, and, consequently, according to the depth and extent of distribution of magnetized rocks, based on the degree of deformation of lithological-stratigraphic complexes and levels by deep faults. Within these tectonic elements, the transformants of the geomagnetic field were comprehensively interpreted with the data of gravitational, thermal and radiochemical fields to increase the reliability of the results of geological interpretation. This made it possible to study the behavior and characteristics of faults, to draw conclusions about the depth of gravitational and magnetically disturbing masses, about the degree of geological heterogeneity of large geostructures, as well as to trace the nature of the manifestation of local structures in geophysical fields. The Central Ustyurt system of dislocation, the Shakhpakhty step and the Assakeaudan depression differ in varying degrees of active tectonics and differentiation by the degree of dislocation of oil and gas prospective objects, fragmentation by faults, by the extent of distribution of reservoir rocks and oil and gas source suite, conditions of conservation of hydrocarbon accumulations, directions and channels of probable hydrocarbon migration, and assumptions are made about the relationship of oil and gas prospective structures and explored hydrocarbon field with large deep faults. The author’s studies of transformants of magnetic and gravitational fields, geothermal and aerogamma spectrometry data clearly indicate in favor of the prospects of oil and gas potential of local structures of the Shakhpakhty step: Utezhan, Kozhantai, Northern Kozhantai, Otynshy. In general, the results obtained will serve as a reliable basis for clarifying and detailing the geological and structural-formation models of the Southern Ustyurt, which can be used as the basis for the design of geological exploration for the exploration of new hydrocarbon field using expensive and time-consuming seismic exploration of CDP-3D and deep drilling

    Classe invertida (flipped classroom). Experiència en el grau d'Infermeria.

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    Projecte finalitzat desembre 2015En l’aula invertida (flipped classroom) (FC), els estudiants treballen fora de classe, tasques prèviament preparades amb aquest fi pel professorat. L’objectiu del estudi es motivar als estudiants suplint per FC les classes teòriques magistrals. Superar favorablement FC evita l’examen final (30% de l’avaluació). Context d’aplicació: grup C, 89 estudiants (finalitzen n=81). Programa de Ciències Psicosocials Aplicades a la Salut, assignatura anual, formació bàsica, 9 ECTS, primer curs, Grau d’Infermeria, tarda, segon semestre, curs 2014-15. Metodologia: resposta escrita a preguntes amb suport bibliogràfic i avaluació amb instruments específics estandaritzats. A classe: avaluació per parells i contrastos verbals sobre continguts, tutelats per la professora, que presenta una segona avaluació setmanal (campus virtual). Resultats: Contrast estadístic de notes FC amb examen test, igual al realitzat en grup A (intraclasse). Puntuació (sobre 10) superior a FC (mitja: 7,96 + DE: 0,67) que en l’examen (mitja 5,89 + DE: 1,26), <0.001. També es contrasten resultats d’examen de FC i de grup A (mitja: 6,02 + DE 1,18) (interclasse) i no es troben diferencies estadísticament significatives 0.508 . Degut a que el grup C (FC) no s’havia preparat ni estudiat l’examen, la diferencia de dècimes mostra una adquisició de coneixements favorable per la experiència flipped classroom.2014PID-UB/5

    Aula invertida: experiencia en el Grado de Enfermería

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    En el aula invertida, los estudiantes trabajan autónomamente tareas previamente preparadas con este fin por el profesorado. Objetivo: evaluar el aula invertida como innovación docente y contrastar los resultados con grupo con docencia tradicional. Contexto: primer curso del Grado de Enfermería en la asignatura troncal Ciencias Psicosociales Aplicadas a la Salud (grupo C, n=81). Metodología: cualitativa y cuantitativa con la inclusión de instrumentos estandarizados ad hoc. Destaca la evaluación por pares y contrastes verbales sobre contenidos tutelados por el profesorado. Se realizó evaluación del grupo control y el grupo experimental y se contrastaron los resultados de las cualificaciones obtenidas. Resultados. Puntuación sobre 10 con medias y desviación estándar: Intraclase, superior en el aula invertida (7,96 + 0,67) frente a (5,89 + 1,26) en examen (p-valor < 0,001). Interclase, grupo experimental (5,89 + 1,26) y grupo control (6,02 + 1,16), (p-valor 0,508). Sin hallazgo de diferencias estadísticamente significativas. Conclusión: Sin preparación para el examen y gran esfuerzo adicional, destacó la satisfacción por parte del profesorado y de los estudiantes, el aula invertida se mostró claramente favorable para la adquisición de conocimientos en la asignatura de Enfermería probada

    Silicon Mie Resonators for Highly Directional Light Emission from monolayer MoS2

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    Controlling light emission from quantum emitters has important applications ranging from solid-state lighting and displays to nanoscale single-photon sources. Optical antennas have emerged as promising tools to achieve such control right at the location of the emitter, without the need for bulky, external optics. Semiconductor nanoantennas are particularly practical for this purpose because simple geometries, such as wires and spheres, support multiple, degenerate optical resonances. Here, we start by modifying Mie scattering theory developed for plane wave illumination to describe scattering of dipole emission. We then use this theory and experiments to demonstrate several pathways to achieve control over the directionality, polarization state, and spectral emission that rely on a coherent coupling of an emitting dipole to optical resonances of a Si nanowire. A forward-to-backward ratio of 20 was demonstrated for the electric dipole emission at 680 nm from a monolayer MoS2 by optically coupling it to a Si nanowire

    Nanoantenna-enhanced ultrafast nonlinear spectroscopy of a single gold nanoparticle

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    Optical nanoantennas are a novel tool to investigate previously unattainable dimensions in the nanocosmos. Just like their radio-frequency equivalents, nanoantennas enhance the light-matter interaction in their feed gap. Antenna enhancement of small signals promises to open a new regime in linear and nonlinear spectroscopy on the nanoscale. Without antennas especially the nonlinear spectroscopy of single nanoobjects is very demanding. Here, we present for the first time antenna-enhanced ultrafast nonlinear optical spectroscopy. In particular, we utilize the antenna to determine the nonlinear transient absorption signal of a single gold nanoparticle caused by mechanical breathing oscillations. We increase the signal amplitude by an order of magnitude which is in good agreement with our analytical and numerical models. Our method will find applications in linear and nonlinear spectroscopy of nanoobjects, ranging from single protein binding events via nonlinear tensor elements to the limits of continuum mechanics

    The therapeutic relationship in inpatient psychiatric care: a narrative review of the perspective of nurses and patients

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    Purpose: to study the significance of 'therapeutic relationship' between nurses and patients within the context of a psychiatric hospital. Method: narrative literature review. Content analysis. Findings: the significance of the therapeutic relationship is quite similar for both nurses and patients in psychiatric hospital units. Nevertheless, several factors may separate the two positions: the time available for the relationship, the negative perceptions on the part of both parties, and the insecurity of the setting. Practice implications: increased knowledge and understanding of the significance of the therapeutic relationship from the perspective of nurses and patients would allow the strengthening of areas of mutual interest

    Identifying quantitative operation principles in metabolic pathways: a systematic method for searching feasible enzyme activity patterns leading to cellular adaptive responses

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    <p>Abstract</p> <p>Background</p> <p>Optimization methods allow designing changes in a system so that specific goals are attained. These techniques are fundamental for metabolic engineering. However, they are not directly applicable for investigating the evolution of metabolic adaptation to environmental changes. Although biological systems have evolved by natural selection and result in well-adapted systems, we can hardly expect that actual metabolic processes are at the theoretical optimum that could result from an optimization analysis. More likely, natural systems are to be found in a feasible region compatible with global physiological requirements.</p> <p>Results</p> <p>We first present a new method for globally optimizing nonlinear models of metabolic pathways that are based on the Generalized Mass Action (GMA) representation. The optimization task is posed as a nonconvex nonlinear programming (NLP) problem that is solved by an outer-approximation algorithm. This method relies on solving iteratively reduced NLP slave subproblems and mixed-integer linear programming (MILP) master problems that provide valid upper and lower bounds, respectively, on the global solution to the original NLP. The capabilities of this method are illustrated through its application to the anaerobic fermentation pathway in <it>Saccharomyces cerevisiae</it>. We next introduce a method to identify the feasibility parametric regions that allow a system to meet a set of physiological constraints that can be represented in mathematical terms through algebraic equations. This technique is based on applying the outer-approximation based algorithm iteratively over a reduced search space in order to identify regions that contain feasible solutions to the problem and discard others in which no feasible solution exists. As an example, we characterize the feasible enzyme activity changes that are compatible with an appropriate adaptive response of yeast <it>Saccharomyces cerevisiae </it>to heat shock</p> <p>Conclusion</p> <p>Our results show the utility of the suggested approach for investigating the evolution of adaptive responses to environmental changes. The proposed method can be used in other important applications such as the evaluation of parameter changes that are compatible with health and disease states.</p

    Flipped Classroom i satisfacció de l'alumnat: una alternativa a les classes magistrals

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    Podeu consultar la Vuitena trobada de professorat de Ciències de la Salut completa a: http://hdl.handle.net/2445/66524En la classe invertida o flipped classroom bona part de la responsabilitat de l’ensenyament-aprenentatge recau en l’alumnat . El professorat elabora el material d’estudi que haurà de preparar l’alumnat abans de classe. En el nostre cas, posteriorment, a l’aula es treballa en petits grups, per contrastar el treball individual, resoldre dubtes, avaluacio per parells i en general, construir l’aprenentatge a partir d’un seguit d’estratègies protocol•litzades, que comporten quantitat de treball i un grau important de satisfaccio tant per a l'alumne com per al professorat
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