991 resultados para 349
A comparison of theoretical Mg VI emission line strengths with active-region observations from SERTS
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R-matrix calculations of electron impact excitation rates in N-like Mg VI are used to derive theoretical electron-density-sensitive emission line ratios involving 2s22p3 - 2s2p4 transitions in the 269-403 Å wavelength range. A comparison of these with observations of a solar active region, obtained during the 1989 flight of the Solar EUV Rocket Telescope and Spectrograph (SERTS), reveals good agreement between theory and observation for the 2s22p3 4S - 2s2p 4 4p transitions at 399.28, 400.67, and 403.30 Å, and the 2s22p3 2p - 2s2p4 2D lines at 387.77 and 387.97 Å. However, intensities for the other lines attributed to Mg VI in this spectrum by various authors do not match the present theoretical predictions. We argue that these discrepancies are not due to errors in the adopted atomic data, as previously suggested, but rather to observational uncertainties or mis-identifications. Some of the features previously identified as Mg VI lines in the SERTS spectrum, such as 291.36 and 293.15 Å, are judged to be noise, while others (including 349.16 Å) appear to be blended.
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Dissertação de Mestrado, Engenharia Eléctrica e Electrónica, Ramo de Tecnologias de Informação e Telecomunicações, Instituto Superior de Engenharia, Universidade do Algarve, 2009
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In his introduction, Pinna (2010) quoted one of Wertheimer’s observations: “I stand at the window and see a house, trees, sky. Theoretically I might say there were 327 brightnesses and nuances of color. Do I have ‘327’? No. I have sky, house, and trees.” This seems quite remarkable, for Max Wertheimer, together with Kurt Koffka and Wolfgang Koehler, was a pioneer of Gestalt Theory: perceptual organisation was tackled considering grouping rules of line and edge elements in relation to figure-ground segregation, i.e., a meaningful object (the figure) as perceived against a complex background (the ground). At the lowest level – line and edge elements – Wertheimer (1923) himself formulated grouping principles on the basis of proximity, good continuation, convexity, symmetry and, often forgotten, past experience of the observer. Rubin (1921) formulated rules for figure-ground segregation using surroundedness, size and orientation, but also convexity and symmetry. Almost a century of research into Gestalt later, Pinna and Reeves (2006) introduced the notion of figurality, meant to represent the integrated set of properties of visual objects, from the principles of grouping and figure-ground to the colour and volume of objects with shading. Pinna, in 2010, went one important step further and studied perceptual meaning, i.e., the interpretation of complex figures on the basis of past experience of the observer. Re-establishing a link to Wertheimer’s rule about past experience, he formulated five propositions, three definitions and seven properties on the basis of observations made on graphically manipulated patterns. For example, he introduced the illusion of meaning by comics-like elements suggesting wind, therefore inducing a learned interpretation. His last figure shows a regular array of squares but with irregular positions on the right side. This pile of (ir)regular squares can be interpreted as the result of an earthquake which destroyed part of an apartment block. This is much more intuitive, direct and economic than describing the complexity of the array of squares.
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In situ observations of clam dredging showed that the effects of the dredge on the benthic macrofauna may not be constant during a tow. A sand buffer forms in front of the gear approximately 10m after the beginning of a tow, and this pushes the sediment partially aside.In this study, we analyse differences in abundance, the number of taxa present, diversity, and evenness within sections of dredge-tracks in a disturbed, fished area and a non-fished area along the southern coast of Portugal. These areas were sampled by divers before and after dredge-fishing activity. At each site, three dredge-tracks were produced. These tracks were divided in three longitudinal sections 1start, middle and end) and two transverse sections 1track and edge). Six quadrats were used to sample macrofauna in each section of every track and edge. Our results show differences exist in macro- faunal distribution and abundance across sections of a dredge-track. These differences should be considered in any assessment of the short-term ecological impact of dredges on benthic macrofauna
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Over the last 15 years, the acceleration in media consolidation has presented a series of policy challenges around diversity of editorial output. While policy debates on national ownership limits and other regulatory interventions are important, developments at the local level are often marginalised. And yet, the direction of travel—towards more consolidation and more deregulation—has arguably been more debilitating for democracy at the local level, where the vast majority of citizens interact with hospitals, schools, transport systems and local councils. The decline of local media—including, in some towns, the wholesale disappearance of local newspapers—leaves citizens starved of information and local institutions less accountable. This article uses an existing conceptual framework for assessing whether and how journalism makes a real-life contribution to democratic life at the local level. Against this normative framework, it then assesses the contribution of hyperlocal media sites to local democracy. We present findings from the most extensive survey of the hyperlocal sector to date, a collaboration with research partners at Cardiff and Birmingham City Universities and Talk About Local, which analysed online questionnaires from over 180 local online media initiatives. Our research offers a unique insight into the funding, operational problems and sustainability of community media sites, and suggests they have the potential to fulfil a vital democratic and civic role. These data inform our conclusions and recommendations for policy initiatives that would invigorate hyperlocal sites and therefore provide a real alternative for otherwise democratically impoverished local communities.
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Tese de Doutoramento, Educação (Desenvolvimento Curricular), 9 de Dezembro de 2013, Universidade dos Açores.
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Evolução, ato ou efeito de evoluir, sequência de transformações, desenvolvimento progressivo. Se tudo à nossa volta se transforma, a indústria tem de acompanhar esse sistema evolutivo, tornando assim imprescindível alterar ou melhorar processos de produção quando estes não se enquadram com a realidade, ou porque o mercado se altera, ou porque as necessidades mudam, ou por simplesmente ser mais rentável. Sendo a Galp Energia uma empresa que se encontra sempre na vanguarda da evolução tecnológica, encontra no Departamento de Engenharia Química do Instituto Superior de Engenharia do Porto um aliado na procura do melhor modo de valorizar os seus produtos. A Refinaria de Matosinhos tem atualmente duas correntes de gasolina leve e uma de refinado que apresentam grande potencialidade de valorização. Parte destas correntes incorporam atualmente a pool de nafta química da refinaria que é vendida à Repsol Polímeros. O desafio que é proposto baseia-se em valorizar essas correntes através da sua isomerização aumentando o seu RON podendo então ter como fim a pool de gasolinas. Tirando partido da tecnologia disponível para este efeito são apresentados quatro cenários de possíveis soluções. Sendo os dois primeiros excluídos por violarem restrições impostas, o terceiro e quarto cenários foram analisados de um ponto de vista económico. O terceiro cenário conduz a gasolina leve da Fábrica de Aromáticos para a pool de gasolinas sem qualquer tratamento e a gasolina leve da Fábrica de Combustíveis continua a integrar a pool de nafta química. O refinado da Fábrica de Aromáticos será enviado para um splitter, sendo a corrente de topo destinada à pool de nafta química e a corrente de fundo enviada a um reator de isomerização, Isomalk-4SM, passando previamente por uma torre de argila de forma a assegurar que a restrição em teor de olefinas no reator não é violada. O efluente, com RON maior, integrará igualmente a pool de gasolinas. No quarto cenário a corrente de refinado da Fábrica de Aromáticos não sofre qualquer tratamento, continuando a alimentar a unidade de solventes, a gasolina leve da Fábrica de Aromáticos irá diretamente para a pool de gasolinas e a gasolina leve da Fábrica de Combustíveis passará pelo Isomalk-2SM para aumentar o índice de octanos garantido assim ter condições de integrar a pool de gasolinas. Dissertação de Mestrado em Engenharia Química Isomerização de Gasolina Leve O terceiro cenário apresenta um aumento de 4 576 773 € anuais nas receitas e o quarto alcança 11 333 982 € anuais. O investimento inicial total do terceiro cenário é de 28 821 608 € quando o quarto cenário carece de um investimento inicial de apenas 18 028 349 €. Quanto aos custos associados à implementação da unidade estes demonstram-se elevados, o terceiro cenário apresenta um custo de 23 133 429 € enquanto o do quarto cenário é de 13 998 797 €. O quarto cenário apresenta-se assim como a solução mais rentável para o objetivo desta dissertação.
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BACKGROUND: Robot surgery is a further step towards new potential developments in minimally invasive surgery. Surgeons must keep abreast of these new technologies and learn their limits and possibilities. Robot-assisted laparoscopic cholecystectomy has not yet been performed in our institution. The purpose of this report is to present the pathway of implementation of robotic laparoscopic cholecystectomy in a university hospital. METHODS: The Zeus(R) robot system was used. Experimental training was performed on animals. The results of our experimental training allowed us to perform our first two clinical cases. RESULTS: Robot arm set-up and trocar placement required 53 and 35 minutes. Operative time were 59 and 45 minutes respectively. The overall operative time was 112 and 80 minutes, respectively. There were no intraoperative complications. Patients were discharged from the hospital after an overnight stay. CONCLUSION: Robotic laparoscopic cholecystectomy is safe and patient recovery similar to those of standard laparoscopy. At present, there are no advantages of robotic over conventional surgery. Nevertheless, robots have the potential to revolutionise the way surgery is performed. Robot surgery is not reserved for a happy few. This technology deserves more attention because it has the potential to change the way surgery is performed.
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Résumé Ce travail a commencé avec une confrontation entre les pensées de P. Ricoeur et E. Levinas sur le thème du rapport à autrui, cette confrontation portant particulièrement sur la place accordée par Levinas, dans son éthique, au thème de la vulnérabilité (ainsi que sur celui de la passivité), tandis que P. Ricoeur reste, selon moi, prioritairement un philosophe de l'activité et qui met, dans la question du rapport à autrui, l'accent sur la reconnaissance de l'autre dans l'empire de ses capacités. Ce débat, et les points qui retenaient en particulier mon attention, m'ont semblé pouvoir être inséré dans le contexte plus large d'une opposition entre éthique de l'autonomie et éthique de la vulnérabilité sur la base de lectures que j'effectuais par ailleurs dans le domaine des éthiques féminines, ou de ce que l'on appelle les éthiques du « care ». Les éthiques féminines, qui se sont développées les 30 dernières années, veulent revenir sur ce qu'elles identifient comme le modèle anthropologique de la modernité, qui privilégie une approche de l'homme en termes d'activité, de rationalité et d'autonomie au mépris d'autres traits comme la passivité, l'affectivité, la dépendance ou la vulnérabilité. Sans nier la rationalité ou l'autonomie de l'homme, elles veulent plutôt compléter une image qu'elles considèrent comme étant incomplète. Sur la base de leur anthropologie alternative, les auteurs qui appartiennent à ce courant proposent une nouvelle définition de l'éthique. Les éthiques du « care » se situent d'une manière générale dans une relation critique avec les éthiques de la justice comme avec les conceptions de l'agent et du patient moral héritées de la philosophie kantienne. Disons brièvement que, plutôt que de faire de l'autonomie et de son respect l'axe de leur réflexion morale, les éthiciennes du « care » insistent sur la signification morale de nos rapports de responsabilité ou de sollicitude à l'égard des personnes vulnérables. Dans la première partie de ma thèse, je reviens sur la genèse de la notion d'autonomie dans la philosophie morale et politique de la pré-modernité, en mettant le développement de ce concept en lien non seulement avec ce que J. Scheewind appelle les « morales de l'autogouvernement », mais aussi avec la naissance des philosophies du sujet et un mouvement général d'intériorisation des sources morales. J'essaye ensuite de dégager le sens de l'idée d'autonomie, sur la base de la notion de liberté positive élaborée par Berlin, avant de distinguer ses différentes significations (autonomie politique, personnelle, morale/autonomie procédurale vs substantielle, autonomie comme capacité, comme droit ou comme idéal). Je me concentre particulièrement sur la conception hiérarchique de l'autonomie personnelle développée par Frankfurt et Dworkin, avant de revenir à la conception kantienne de l'autonomie morale. Je consacre ensuite une section aux conceptions relationnelles de l'autonomie, ce qui me permet de faire le lien avec le thème de la vulnérabilité. Pour le développement historique de cette notion dans la pensée contemporaine, j'insiste, outre sur les éthiques du « care », sur les développements de la bioéthique et la philosophie de H. Jonas. Après un travail de définition du concept de vulnérabilité, j'élabore les éléments d'une éthique de la vulnérabilité que j'essaie d'articuler à la notion d'autonomie. Dans la deuxième partie, je confronte les éthiques de Ricoeur et de Levinas dans la perspective de l'opposition autonomie/vulnérabilité, en montrant leurs limites respectives.
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OBJECTIVE: To investigate the planning of subgroup analyses in protocols of randomised controlled trials and the agreement with corresponding full journal publications. DESIGN: Cohort of protocols of randomised controlled trial and subsequent full journal publications. SETTING: Six research ethics committees in Switzerland, Germany, and Canada. DATA SOURCES: 894 protocols of randomised controlled trial involving patients approved by participating research ethics committees between 2000 and 2003 and 515 subsequent full journal publications. RESULTS: Of 894 protocols of randomised controlled trials, 252 (28.2%) included one or more planned subgroup analyses. Of those, 17 (6.7%) provided a clear hypothesis for at least one subgroup analysis, 10 (4.0%) anticipated the direction of a subgroup effect, and 87 (34.5%) planned a statistical test for interaction. Industry sponsored trials more often planned subgroup analyses compared with investigator sponsored trials (195/551 (35.4%) v 57/343 (16.6%), P<0.001). Of 515 identified journal publications, 246 (47.8%) reported at least one subgroup analysis. In 81 (32.9%) of the 246 publications reporting subgroup analyses, authors stated that subgroup analyses were prespecified, but this was not supported by 28 (34.6%) corresponding protocols. In 86 publications, authors claimed a subgroup effect, but only 36 (41.9%) corresponding protocols reported a planned subgroup analysis. CONCLUSIONS: Subgroup analyses are insufficiently described in the protocols of randomised controlled trials submitted to research ethics committees, and investigators rarely specify the anticipated direction of subgroup effects. More than one third of statements in publications of randomised controlled trials about subgroup prespecification had no documentation in the corresponding protocols. Definitive judgments regarding credibility of claimed subgroup effects are not possible without access to protocols and analysis plans of randomised controlled trials.
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Red blood cell (RBC) parameters such as morphology, volume, refractive index, and hemoglobin content are of great importance for diagnostic purposes. Existing approaches require complicated calibration procedures and robust cell perturbation. As a result, reference values for normal RBC differ depending on the method used. We present a way for measuring parameters of intact individual RBCs by using digital holographic microscopy (DHM), a new interferometric and label-free technique with nanometric axial sensitivity. The results are compared with values achieved by conventional techniques for RBC of the same donor and previously published figures. A DHM equipped with a laser diode (lambda = 663 nm) was used to record holograms in an off-axis geometry. Measurements of both RBC refractive indices and volumes were achieved via monitoring the quantitative phase map of RBC by means of a sequential perfusion of two isotonic solutions with different refractive indices obtained by the use of Nycodenz (decoupling procedure). Volume of RBCs labeled by membrane dye Dil was analyzed by confocal microscopy. The mean cell volume (MCV), red blood cell distribution width (RDW), and mean cell hemoglobin concentration (MCHC) were also measured with an impedance volume analyzer. DHM yielded RBC refractive index n = 1.418 +/- 0.012, volume 83 +/- 14 fl, MCH = 29.9 pg, and MCHC 362 +/- 40 g/l. Erythrocyte MCV, MCH, and MCHC achieved by an impedance volume analyzer were 82 fl, 28.6 pg, and 349 g/l, respectively. Confocal microscopy yielded 91 +/- 17 fl for RBC volume. In conclusion, DHM in combination with a decoupling procedure allows measuring noninvasively volume, refractive index, and hemoglobin content of single-living RBCs with a high accuracy.
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Raised blood pressure (BP) is a major risk factor for cardiovascular disease. Previous studies have identified 47 distinct genetic variants robustly associated with BP, but collectively these explain only a few percent of the heritability for BP phenotypes. To find additional BP loci, we used a bespoke gene-centric array to genotype an independent discovery sample of 25,118 individuals that combined hypertensive case-control and general population samples. We followed up four SNPs associated with BP at our p < 8.56 × 10(-7) study-specific significance threshold and six suggestively associated SNPs in a further 59,349 individuals. We identified and replicated a SNP at LSP1/TNNT3, a SNP at MTHFR-NPPB independent (r(2) = 0.33) of previous reports, and replicated SNPs at AGT and ATP2B1 reported previously. An analysis of combined discovery and follow-up data identified SNPs significantly associated with BP at p < 8.56 × 10(-7) at four further loci (NPR3, HFE, NOS3, and SOX6). The high number of discoveries made with modest genotyping effort can be attributed to using a large-scale yet targeted genotyping array and to the development of a weighting scheme that maximized power when meta-analyzing results from samples ascertained with extreme phenotypes, in combination with results from nonascertained or population samples. Chromatin immunoprecipitation and transcript expression data highlight potential gene regulatory mechanisms at the MTHFR and NOS3 loci. These results provide candidates for further study to help dissect mechanisms affecting BP and highlight the utility of studying SNPs and samples that are independent of those studied previously even when the sample size is smaller than that in previous studies.
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Los más altos valores de producción durante el año 1964 se hallaron en las regiones de divergencia, de mezcla vertical y capa de mezcla poco profunda, o donde el agua superficial era enriquecida a través de los afloramientos favorecidos por la acción de los vientos. La distribución de producción primaria en superficie fue muy similar a la producción total. La producción diaria entre las latitudes 4-6° S tuvo un promedio de 0.27 gr C/m2 (0.04-1.51 gr C/m2), y entre las latitudes 6°-18°30 'S de 0.45 gr C/m2 (0.03-2.42 gr C/m2 ), o sea una producción anual de 97 y 162 gr C/m2 , respectivamente. La máxima producción hallada en la Corriente Costera Peruana correspondió al Verano, y la mínima al Invierno, con una producción promedio anual de 190 gr C/m2. Hubo una variación geográfica de la producción total en la faja costera de 60 millas de ancho. A lo largo del litoral peruano los mayores valores de producción se presentaron entre las latitudes 8-9° S y 16-17° S con valores promedio de 1.00 y 1.30 gr C/m2, respectivamente.
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Se estimaron las biomasas de las especies: anchoveta (Engraulis ringens), vinciguerria (Vinciguerria lucetia), falso volador (Prionotuis stephanophrys), bagre (Galeichthys peruvianus) y múnida (Pleuroncodes monodon), mediante técnicas hidroacústicas durante el Crucero 9811-12 de Evaluación Hidroacústica de Recursos Pelágicos, a bordo del BIC José Olaya Balandra desde el 28 de noviembre al 23 de diciembre de 1998 entre la Isla Lobos de Tierra y el Morro Sama. El trayecto utilizado fue el sistemático paralelo con transectos perpendiculares a la costa con 14 mn de separación. El equipo utilizado fue la ecosonda científica EK 500 SIMRAD en frecuencias de 38 y 120 kHz, en un rango de detección de 3 a 250 m de profundidad. Se realizó la calibración de equipos en la Isla San Lorenzo, Callao (12° S). Para la obtención de las biomasas se utilizó el método de estratificación por áreas isoparalitorales. La biomasa de anchoveta se estimó en 2.700.205 t (± 23,92%), las mayores biomasas se encontraron entre los grados 13 y 14 de latitud sur. La biomasa de la vinciguerria se calculó en 2.248.405 t (± 31,28%) con un mayor porcentaje en el grado 10 de latitud sur. La biomasa del falso volador se estimó en 422.349 t (± 38,82%), la del bagre se determinó en 409.470 t (± 30,32%) y de la múnida en 911.976 t (± 31,78 %).